Question: What Does Airtight Container Mean?
Whats is a seal?
1 : a sea mammal that swims with flippers, lives mostly in cold regions, bears young on land, feeds on fish and other sea animals (as squid), and is sometimes hunted for its fur, hide, or oil.
2 : the soft fur of a seal.
Kids Definition of seal (Entry 2 of 3).
What does blight mean?
(Entry 1 of 2) 1 botany. a : a disease or injury of plants marked by the formation of lesions, withering, and death of parts (such as leaves and tubers) potato blight. b : an organism (such as an insect or a fungus) that causes blight.
What is the meaning of indisputable?
English Language Learners Definition of indisputable : impossible to question or doubt : not disputable. See the full definition for indisputable in the English Language Learners Dictionary. indisputable. adjective. in·dis·put·able | \ ˌin-di-ˈspyü-tə-bəl, in-ˈdi-spyə- \
What do you store in an airtight container?
Sugars: Sugar is hydroscopic, meaning it attracts moisture, so make sure to keep sugars in airtight containers to prevent clumping. Rices, Beans, and Whole Grains: Airtight containers keep moisture and outside flavors and odors out. Spices: Make your spices last longer by keeping them in airtight containers.
What is a good airtight container?
Keep Food Fresher for Longer with the Best Airtight Food Storage ContainersRubbermaid Brilliance Pantry Organization & Food Storage Containers. … Anchor Hocking TrueSeal Round Glass Food Storage Containers. … OXO Good Grips 5-Piece POP Container Set. … Airscape Coffee and Food Storage Canister.More items…•Jan 11, 2021
What is the best airtight container?
The Rubbermaid Brilliance Pantry Food Storage Containers are the best dry storage containers for most people. The lids and containers in this set are very sturdy and seal tightly, even after multiple runs through the dishwasher.
Can you store baking soda in a Mason jar?
Yes, you can. You can also store your baking powder in glass jars.
Why is Tupperware bad for you?
Is a Ziploc bag airtight?
Ziploc bags have a tight seal, but they are not completely airtight. The unique zipper seal will minimize the amount of air that can slowly seep into the bag to keep your foods fresher longer.
Do airtight containers keep bugs out?
Airtight containers are designed to keep your food fresh and eliminate the risk of pantry pests. So, it's almost impossible for weevils to enter a high-quality airtight container. If you notice any bugs appear in your airtight container, it's likely there were already microscopic weevil eggs in your food.
Can mold grow in airtight containers?
Spores are indeed everywhere. And your food wasn't sterile when you put in the container. So leave a "sealed" container with food long enough, and if there is enough water in the container, something will grow.
What are airtight containers used for?
The airtight lids keep foods, such as cookies, crackers, chips, and cereals form becoming stale for a longer period of time when stored at room temperature. Plastic containers work well for all types of storage. They store well together and can really help organize a storage area.
Can you store fruit in an airtight container?
Cherries: Keep in airtight container. Don't wash cherries until ready to eat – any added moisture encourages mold. Citrus: Store in a cool place with good airflow and never in an airtight container. Berries: Berries are fragile.
What is the safest food storage container?
Glass Storage ContainersSafest: Glass Storage Containers The safest choice for food storage is glass. A couple of years ago, glass food storage containers were hard to come by and expensive.
How do you store flour for years?
You can leave your flour in its original bag, but for long-term storage, it's best to move it to an air-tight container that can protect against smells (flour will absorb odors) and liquids from the freezer walls.
How do you know if a container is airtight?
What do you mean by airtight?
1 : impermeable to air or nearly so an airtight seal. 2a : having no noticeable weakness, flaw, or loophole an airtight argument. b : permitting no opportunity for an opponent to score an airtight defense.
Is it better to store food in glass or plastic?
Glass is generally safer than plastic when it comes to food storage. You can heat and re-heat glass containers over and over without worrying about any chemical leeching into your food, and they're more durable, so your containers won't be dyed or smell like food residue after a while of use.
Is a jar an airtight container?
Canning (Mason) jars will be airtight once the lid is screwed on only if the jar, lid, and ring are not compromised. However, there will still be air inside the jar. The only way to remove air from the jar is by following the safe canning practices recommended by the USDA, which forms a vacuum.
Do airtight containers work?
Keeping food in airtight containers slows down oxidation Plus, storing your food in airtight food containers help prevent rancidity, especially in oily and fatty foods, since oxidation is the reason why these foods go rancid.


.GooglePublicDns2);
client.EnableAuditTrail = true;
client.UseCache = true;
var result = await client.QueryAsync("google.com", QueryType.A);
TCP Settings
Enabling the UseTcpFallback property allows the client to run the same query via TCP in case the UDP result was truncated.
This can happen in cases where the UDP result exceeds the maximum supported size of the DNS server can return.
The default size is usually 4096 or 512 bytes.
This setting is enabled per default.
Setting UseTcpOnly to true would disable any UDP communication. This can be useful in case UDP transport is disabled through firewall rules for example.
Continue and Retry on DNS Error
If multiple DNS name servers are configured for the ILookupClient instance, per default, the client will try the next server (in random or configured order depending on UseRandomNameServer) if the current server responded with a DNS error.
To change that behavior and stop after the first response, disable the ContinueOnDnsError option.
Throw on DNS Errors
Enabling the ThrowDnsErrors property would throw a DnsResponseException if the result of a DNS query does contain a response code in the header other than NoError.
This setting is disabled per default.
This setting can be useful if you prefer to handle such errors with try-catch blocks instead of inspecting the result object.
Also, some methods and extensions of IDnsQuery do not return a DnsResponseMessage with the full details but may return a string or null in case of an error. Enabling this property would throw an exception instead.
Handle multiple DNS Nameservers
If multiple DNS name servers are configured for the ILookupClient instance, per default, the servers are used in random order.
To change that behavior and always start with the first one and then fall back to the next, disable the UseRandomNameServer option.


text:
The dam, founded on rock and working under the pressure of dammed water, is endangered by the impact of adverse filtration occurances. To protect against excessive filtration, a cement-grout curtain was carried out in the rock foundation of the dam, up to the max depth of 60 m. However, water seepages on the downstream side of the dam, indicated leaks in some sections of the concrete massive. Finding solution to this problem was commissioned to Hydroprojekt who elaborated comprehensive design documentation. Geological and geotechnical surveys performed under the contract allowed to determine the causes of adverse filtration occurrences in the body of the right abutment of the dam. In order to remove them, the walls of the pipeline canal, running in the right abutment of the dam were water proofed and water inflow to the canal was shut off with a concrete wall. In the next step, new sections of the cement-grout curtain, sealing the rock foundation and shutting off the inflow of the hillside waters to the dam, were performed. The applied solutions proved to be effective and caused significant reduction of the filtration process.
The Solina dam is the highest dam in Poland (81.8 m), the longest concrete one (664.8 m), and the structure with the largest volume of the concrete massif (768,000 m3).
SCOPE OF SERVICES:
- conceptual designs
- preliminary designs
- detailed designs
- construction supervision on behalf of the author
PGE Energia Odnawialna S.A.
Podkarpacie Voivodship, Lesk County, Solina Community, Poland
2010 - 2011

source: m-a-p/FineFineWeb


text:
Drone congregation areas
The BeeHolder, July 2010
July 1, 1792
'There is a natural occurrence to be met with upon the highest part of our down on hot summer days, which always amuses me much, without giving me any satisfaction with respect to the cause of it; & that is a loud audible humming of bees in the air, tho' not one insect is to be seen. This sound is to be heard distinctly the whole common through, from the Moneydells, to Mr White's avenue-gate. Any person would suppose that a large swarm of bees was in motion, & playing about over his head. This noise was heard last week on June 28th.'
Gilbert White, 'A Natural History of Selborne'
The above writing is believed to be the earliest known reference to what we now call a drone congregation area. (DCA)
Although a lot of research has been carried out into drone behaviour in DCAs, no one has yet satisfactorily explained why the DCAs occur in certain places, and even more mystifying, why they persist in the same places year after year. (The DCA referred to by Gilbert White is still in use today.
Virtually all drones die in the previous autumn, so how do the new drones know where to go? Light distribution and the contour of the horizon seem to play a part in choosing a site Pechhacker 1994) and Zmarlicki and Morse determined that most DCAs seem to be located over an open area of land of about a hectare, protected from strong winds.Obstructions such as high buildings and tall trees are avoided, but not all open spaces are used. The flyways connecting the DCAs tend to follow lines of trees or hedges, etc. There may be several DCAs adjacent to each other. One study showed that a 10 sq k. area next to an commercial apiary contained at least 26 DCAs and 18km of flyways. Based on radar images a DCA was defined as an area approx. 100m in diameter, where the drones fly at a mean height of 25m-it depends on wind velocity. The stronger the wind, the lower the drones fly.
The night is still young and our drinks are yet long,
The fire's burning bright and here brave is the throng,
So now I will sing you a sooth little song
Of the busy brown bee - with a ding and a dong.
—J. R. R. Tolkien, Natura Apis (A drinking song)
Many drones seem to stay faithful to one DCA, but may visit another in the same general direction. Two to three miles seems to be an average distance for a drone to fly, but they have been known to travel up to 5 miles. For a queen rearer wanting pure matings from a mating apiary, it seems that this is the minimum distance there must be from any other hives, or else a physical barrier of 500m or more must be present. The parentage of a sample of drones was tested in Germany in 1998, and the conclusion reached was that all the colonies in the area seemed to send roughly the same proportion of delegates to the meeting, thus minimising the chances of inbreeding. (C.Collinson, Bee Culture, Sep. 2008) Because mating takes place in flight, it is difficult to observe.
Modern technology such as radar, combined with the technique of tethering a virgin queen to a moving line, has shown drones detecting a virgin forming a long cometshaped tail behind her. Recent studies have shown that the drones find the virgin primarily by smell. One of the components of queen substance, called 9-ODA, attracts drones during mating flights. (Apis UK, July 2008). However, it has also been noticed that drones will momentarily chase anything that moves, butterflies, dragonflies or a thrown stone, so presumably eyesight plays a part as well.
Drones have to be very fit and well developed to mate with a queen. In addition to the excellent flying power needed to catch the queen, they must have ample supplies of spermatazoa, as only a fraction of each ejaculate will migrate to the queen's spermatheca. (Woyke and Jasinski, 1973) In a series of studies made by Duay et al, in 2002, it was shown that the effects of parasitism by Varroa destructor in the larval stage, could seriously affect the drones ability to mate. A significant reduction in drone body weight resulted from invasion by only one female varroa mite, and two or more mites reduced drone life expectancy so much that sexual maturity was seldom reached. Varroa parasitism by only one mite hardly affected flying power but sperm production was reduced by 24%. In those drones that survived, two female mites invasion resulted in greatly reduced flying power and a sperm reduction of 45%. Other interesting facts to emerge are;
- Drones like it hot. Flying to a DCA and gathering enough drones to form a comet only occurs at 18C or above.
- They are very good time keepers, generally flying between 2.00pm and 6.00pm This varies according to the weather.
- Drones returning to the apiary outside these times were not interested in a queen.
- Maximum flight height in flyways is 21m, but in DCAs it can reach 50m.
- Drones can make several trips to a DCA in an afternoon, returning to the hive to refuel when necessary. Each mating flight lasts about 30 mins.
- The number of drones in a DCA can vary enormously, from hundreds to thousands.
- Usually, 7 to 11 drones will mate with a queen. About 90 million sperm will be deposited in her oviducts, and a mixture of about 7 million of them will be stored in her spermatheca
The actual process of mating has now been documented quite thoroughly. drone mounts a queen and inserts his endophallus and ejaculates his semen. During ejaculation he falls backwards and his endophallus is torn from his body, remaining in the queen. Any subsequent males mating with the queen dislodge the previous drones endophallus and leave their own in its place. The drones die quickly with their abdomens ruptured in this fashion. The queen returns to her hive still carrying the endophallus of the last male to mate with her. Beekeepers call this the 'mating sign' It will be removed by the nurse bees. The process is described very clearly in 'The Biology of the Honeybee' by Mark Winston.
Once the mating season is over, the 'raison d'etre' of the drones is gone. Only in queenless or very well provisioned colonies will some be allowed to overwinter in the hive. There is no sentimentality in nature, and drones with no function to perform are simply a drain on valuable resources, ie honey stores. In the autumn they are refused entry to the hive, or have their wings bitten and are forcibly ejected, to die of cold and starvation.
'Bees, Biology and Management' by Peter G. Kevan.
'The Biology of the Honeybee' by Mark L. Winston.
'Anatomy and Dissection of the Honeybee' by H. A.Dade.
'Bee Genetics and Breeding' edited by Thomas Rinderer
'Drone Congregation Areas' by C. Collison. (Bee Culture, Sep 2008)
'Beekeeping' by Kim Flottum.
'Pheromones of the Social bees' by John Free.
'The Honey Bees of the British Isles' by Beowolf Cooper.
And why is understanding of drone behaviour so important? Understanding drones may well be the key to controlling varroa. Drones range over a 5 mile radius. Workers range over a 3 mile radius. Drones are tolerated, even welcomed in strange hives. Worker bees are prevented from entering starange hives unless they have a full load of honey. For the varroa mite to spread it needs to defferentially lay in drone cells. This behaviour has evolved within the primary host/parastite, that of apis cerana/Varroa destructor. Those who keep the Honey Bee, Apis melifera, have long noticed the preference for varroa to lay in drone cells. This has lead to the destruction of drone cells becoming an indicator of varroa infestation. Stimulation of the queen to lay whole frames of drones which are then destroyed is now a regular part of Integrated Pest Management IPM.

source: openbmb/Ultra-FineWeb


Hilbert's Nullstellensatz
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Hilbert's Nullstellensatz (German for "theorem of zeros," or more literally, "zero-locus-theorem" – see Satz) is a theorem that establishes a fundamental relationship between geometry and algebra. This relationship is the basis of algebraic geometry, an important branch of mathematics. It relates algebraic sets to ideals in polynomial rings over algebraically closed fields. This relationship was discovered by David Hilbert who proved the Nullstellensatz and several other important related theorems named after him (like Hilbert's basis theorem).
Let k be a field (such as the rational numbers) and K be an algebraically closed field extension (such as the complex numbers), consider the polynomial ring k[X1,X2,..., Xn] and let I be an ideal in this ring. The algebraic set V(I) defined by this ideal consists of all n-tuples x = (x1,...,xn) in Kn such that f(x) = 0 for all f in I. Hilbert's Nullstellensatz states that if p is some polynomial in k[X1,X2,..., Xn] that vanishes on the algebraic set V(I), i.e. p(x) = 0 for all x in V(I), then there exists a natural number r such that pr is in I.
An immediate corollary is the "weak Nullstellensatz": The ideal I in k[X1,X2,..., Xn] contains 1 if and only if the polynomials in I do not have any common zeros in Kn. It may also be formulated as follows: if I is a proper ideal in k[X1,X2,..., Xn], then V(I) cannot be empty, i.e. there exists a common zero for all the polynomials in the ideal in every algebraically closed extension of k. This is the reason for the name of the theorem, which can be proved easily from the 'weak' form using the Rabinowitsch trick. The assumption of considering common zeros in an algebraically closed field is essential here; for example, the elements of the proper ideal (X2 + 1) in R[X] do not have a common zero in R. With the notation common in algebraic geometry, the Nullstellensatz can also be formulated as
for every ideal J. Here, \sqrt{J} denotes the radical of J and I(U) is the ideal of all polynomials that vanish on the set U.
In this way, we obtain an order-reversing bijective correspondence between the algebraic sets in Kn and the radical ideals of K[X1,X2,..., Xn]. In fact, more generally, one has a Galois connection between subsets of the space and subsets of the algebra, where "Zariski closure" and "radical of the ideal generated" are the closure operators.
As a particular example, consider a point P = (a_1, \cdots, a_n) \in K^n. Then I(P) = (X_1 - a_1, \cdots, X_n - a_n). More generally,
\sqrt{I} = \bigcap_{P \in V(I)} (X_1 - a_1, \cdots, X_n - a_n), \quad P = (a_1, \cdots, a_n).
As another example, an algebraic subset W in Kn is irreducible (in the Zariski topology) if and only if I(W) is a prime ideal.
Proof and generalization[edit]
There are many known proofs of the theorem. One proof is the following:
 1. Note that it is enough to prove Zariski's lemma: a finitely generated algebra over a field k that is a field is a finite field extension of k.
 2. Prove Zariski's lemma.
The proof of Step 1 is elementary. Step 2 is deeper. It follows, for example, from the Noether normalization lemma. See Zariski's lemma for more. Here we sketch the proof of Step 1.[1] Let A = k[t_1,..., t_n] (k algebraically closed field), I an ideal of A and V the common zeros of I in k^n. Clearly, \sqrt{I} \subseteq I(V). Let f \not\in \sqrt{I}. Then f \not\in \mathfrak{p} for some prime ideal \mathfrak{p}\supseteq I in A. Let R = (A/\mathfrak{p}) [f^{-1}] and \mathfrak{m} a maximal ideal in R. By Zariski's lemma, R/\mathfrak{m} is a finite extension of k; thus, is k since k is algebraically closed. Let x_i be the images of t_i under the natural map A \to k. It follows that x = (x_1,..., x_n) \in V and f(x) \ne 0.
The Nullstellensatz will also follow trivially once one systematically developed the theory of a Jacobson ring, a ring in which a radical ideal is an intersection of maximal ideals. Let R be a Jacobson ring. If S is a finitely generated R-algebra, then S is a Jacobson ring. Further, if \mathfrak{n}\subset S is a maximal ideal, then \mathfrak{m} := \mathfrak{n} \cap R is a maximal ideal of R, and S/\mathfrak{n} is a finite extension field of R/\mathfrak{m}.
Another generalization states that a faithfully flat morphism f: Y \to X locally of finite type with X quasi-compact has a quasi-section, i.e. there exists X' affine and faithfully flat and quasi-finite over X together with an X-morphism X' \to Y
Effective Nullstellensatz[edit]
In all of its variants, Hilbert's Nullstellensatz asserts that some polynomial g belongs or not to an ideal generated, say, by f1,..., fk; we have g = f r in the strong version, g = 1 in the weak form. This means the existence or the non existence of polynomials g1,..., gk such that g = f1g1 +... + fkgk The usual proofs of the Nullstellensatz are non effective in the sense that they do not give any way to compute the gi.
It is thus a rather natural question to ask if there is an effective way to compute the gi (and the exponent r in the strong form) or to prove that they do not exist. To solve this problem, it suffices to provide an upper bound on the total degree of the gi: such a bound reduces the problem to a finite system of linear equations that may be solved by usual linear algebra techniques. Any such upper bound is called an effective Nullstellensatz.
A related problem is the ideal membership problem, which consists in testing if a polynomial belongs to an ideal. For this problem also, a solution is provided by an upper bound on the degree of the gi. A general solution of the ideal membership problem provides an effective Nullstellensatz, at least for the weak form.
In 1925, Grete Hermann gave an upper bound for ideal membership problem that is doubly exponential in the number of variables. In 1982 Mayr and Meyer gave an example where the gi have a degree that is at least double exponential, showing that every general upper bound for the ideal membership problem is doubly exponential in the number of variables.
Until 1987, nobody had the idea that effective Nullstellensatz was easier than ideal membership, when Brownawell gave an upperbound for the effective Nullstellensatz that is simply exponential in the number of variables. Brownawell proof uses calculus techniques and thus is valid only in characteristic 0. Soon after, in 1988, János Kollár gave a purely algebraic proof valid in any characteristic, leading to a better bound.
In the case of the weak Nullstellensatz, Kollár's bound is the following:[2]
Let f1,..., fs be polynomials in n ≥ 2 variables, of total degree d1 ≥... ≥ ds. If there exist polynomials gi such that f1g1 +... + fsgs = 1, then they can be chosen such that
\deg(f_ig_i) \le \max(d_s,3)\prod_{j=1}^{\min(n,s)-1}\max(d_j,3).
This bound is optimal if all the degrees are greater than 2.
If d is the maximum of the degrees of the fi, this bound may be simplified to
Kollár's result has been improved by several authors. M. Sombra has provided the best improvement, up to date, giving the bound[3]
\deg(f_ig_i) \le 2d_s\prod_{j=1}^{\min(n,s)-1}d_j.
His bound is better than Kollár's as soon as at least two of the degrees that are involved are lower than 3.
Projective Nullstellensatz[edit]
We can formulate a certain correspondence between homogeneous ideals of polynomials and algebraic subsets of a projective space, called the projective Nullstellensatz, that is analogous to the affine one. To do that, we introduce some not


text:
Efficient HVAC Systems May Qualify for Tax Breaks
HVAC, construction, energy efficiency, operating costs, green design June 19, 2008
I'm Ed Sullivan, editor of Building Operating Management magazine. Today's topic is potential tax benefits for very efficient HVAC systems.
The Energy Policy Act of 2005 – better known as EPAct – provides tax deductions for the installation of HVAC systems with energy costs that are at least 16.7 percent than an HVAC system designed to meet the 2001 edition of ASHRAE 90.1. The deductions apply both to new construction and to renovations. Although HVAC component upgrades typically don't qualify, a comprehensive system installation is a good candidate. So are geothermal and thermal storage systems.
Getting the deduction isn't easy. EPAct requires that the performance of the system be substantiated by energy modeling. And the modeling required is different than the modeling required by LEED. But rebates may be available to cover at least some of the cost of modeling, though the rebates must be obtained before the modeling is conducted.
The tax benefits are currently due to expire at the end of 2008. But there are proposals in Congress to extend the tax breaks. For green buildings and other buildings where significant HVAC work is planned, the tax breaks are worth looking into.


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When typing < or > in LaTeX and compiling with pdflatex, the less than and greater than symbols appear at upside down exclamation points. I'm not in math mode.
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using it in a regression results table in a paper. – biased_estimator Aug 28 '10 at 2:44
_USER_: "This example holds true for all cases where n >= 3". – SabreWolfy Feb 2 '12 at 13:02
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4 Answers
up vote 79 down vote accepted
Geoffs tip with \textless and \textgreater will work well for you. However, you could type these symbols < and > directly in your editor and they would be correctly printed if you use the recommended font encoding, Cork resp. T1:
Have a look at the T1 encoding table, search for the symbols < and >. Afterwards, open the OT1 encoding table, which is the default. At the two corresponding places you will find the upside down exclamation resp. quotation mark. That should explain it.
For further reasons, why you should use T1 encoding, have a look at this question: Why should I use \usepackage[T1]{fontenc}?
You should use a font supporting T1. For instance use the very good Latin Modern font, derived from the standard fonts:
Or install the cm-super package which provides the standard Computer Modern fonts with T1 support.
share|improve this answer
Further reading: Latin Modern vs cm-super? – doncherry Jan 31 '13 at 6:46
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Use \textless and \textgreater.
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unless they are part of a math expression, in which case they should be between dollar signs or \(... \) along with the rest of the math expression. – barbara beeton Aug 26 '10 at 19:51
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May be using some other sane font encoding, something like \usepackage[T1]{fontenc} or something. (Well, I don't think any of this legacy font encoding and input encoding is sane any way).
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+1 for your opinion in parentheses! – Lover of Structure Dec 26 '13 at 0:36
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What I usually do is just enter mathmode to type them, e.g. This object is $<$ that object.
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That is generally considered poor style. You should just write out "This object is less than that object." Occasionally, you'll see "foo is <0." This looks bad. – TH. Aug 27 '10 at 23:32
That's definitely true. However, if you're using LaTeX to organize your thoughts (as i often do), 'good style' equates to 'will I understand what I wrote if I come back and look at it in a week'! – Avi Steiner Sep 3 '10 at 3:30
_USER_.: I agree with you. My experiency tells me too that text and math code should not be mixed up. Good style would be either writing "The variable $foo$ is less than zero." (as you mentioned) or "The variable $foo$ satisfies the relation/condition $foo<0$.", which would probably suit your application. Good style means also to define variables at the first use. – strpeter Dec 7 '13 at 8:07
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text:
- the act or an instance of motivating.
- the state or condition of being motivated.
- something that motivates; inducement; incentive.
Even a little would be nice.
|1.||the normal, non warring condition of a nation, group of nations, or the world.|
|2.||an agreement or treaty between warring or antagonistic nations, groups, etc., to end hostilities and abstain from further fighting or antagonism: the Peace of Ryswick.|
|3.||a state of mutual harmony between people or groups, esp. in personal relations: Try to live in peace with your neighbors.|
|4.||the normal freedom from civil commotion and violence of a community; public order and security: He was arrested for being drunk and disturbing the peace.|
|5.||cessation of or freedom from any strife or dissension.|
|6.||freedom of the mind from annoyance, distraction, anxiety, an obsession, etc.; tranquility; serenity.|
|7.||a state of tranquility or serenity: May he rest in peace.|
|8.||a state or condition conducive to, proceeding from, or characterized by tranquillity: the peace of a mountain resort.|
|9.||silence; stillness: The cawing of a crow broke the afternoon's peace.|
|10.||) a comedy (421 b.c.) by Aristophanes.|
|11.||(used to express greeting or farewell or to request quietness or silence).|
|12.||Obsolete. to be or become silent.|
|13.||at peace, |
|14.||hold or keep one's peace, to refrain from or cease speaking; keep silent: He told her to hold her peace until he had finished.|
|15.||keep the peace, to maintain order; cause to refrain from creating a disturbance: Several officers of the law were on hand to keep the peace.|
|16.||make one's peace with, to become reconciled with: He repaired the fence he had broken and made his peace with the neighbor on whose property it stood.|
|17.||make peace, to ask for or arrange a cessation of hostilities or antagonism|
For much of the past seven years, President Bush and Vice President Dick Cheney have waged a clandestine operation inside the White House. It has involved thousands of military personnel, private presidential letters and meetings that were kept off their public calendars or sometimes left the news media in the dark.
Their mission: to comfort the families of soldiers who died fighting in Afghanistan and Iraq since the Sept. 11 terrorist attacks and to lift the spirits of those wounded in the service of their country.
On Monday, the president is set to make a more common public trip - with reporters in tow - to Walter Reed Army Medical Center, home to many of the wounded and a symbol of controversy earlier in his presidency over the quality of care the veterans were receiving.
But the size and scope of Mr. Bush's and Mr. Cheney's private endeavors to meet with wounded soldiers and families of the fallen far exceed anything that has been witnessed publicly, according to interviews with more than a dozen officials familiar with the effort.
"People say, 'Why would you do that?'" the president said in an Oval Office interview with The Washington Times on Friday. "And the answer is: This is my duty. The president is commander in chief, but the president is often comforter in chief, as well. It is my duty to be - to try to comfort as best as I humanly can a loved one who is in anguish.
Mr. Bush, for instance, has sent personal letters to the families of every one of the more than 4,000 troops who have died in the two wars, an enormous personal effort that consumed hours of his time and escaped public notice. The task, along with meeting family members of troops killed in action, has been so wrenching - balancing the anger, grief and pride of families coping with the loss symbolized by a flag-draped coffin - that the president often leaned on his wife, Laura, for emotional support.
"I lean on the Almighty and Laura," Mr. Bush said in the interview. "She has been very reassuring, very calming."
Mr. Bush also has met privately with more than 500 families of troops killed in action and with more than 950 wounded veterans, according to White House spokesman Carlton Carroll. Many of those meetings were outside the presence of the news media at the White House or at private sessions during official travel stops, officials said.
The first lady said those private visits, many of which she also attended, took a heavy emotional toll, not just on the president, but on her as well.
|1.||any of the numerous fine, usually cylindrical, keratinous filaments growing from the skin of humans and animals; a pilus.|
|2.||an aggregate of such filaments, as that covering the human head or forming the coat of most mammals.|
|3.||a similar fine, filamentous outgrowth from the body of insects, spiders, etc.|
|4.||Botany. a filamentous outgrowth of the epidermis.|
|5.||cloth made of hair from animals, as camel and alpaca.|
|6.||a very small amount, degree, measure, magnitude, etc.; a fraction, as of time or space: He lost the race by a hair.|
|7.||get in someone's hair, Slang. to annoy or bother someone: Their snobbishness gets in my hair.|
|8.||hair of the dog, Informal. a drink of liquor, supposed to relieve a hangover: Even a hair of the dog didn't help his aching head. Also, hair of the dog that bit one.|
|9.||let one's hair down, Informal. |
|10.||make one's hair stand on end, to strike or fill with horror; terrify: The tales of the jungle made our hair stand on end.|
|11.||split hairs, to make unnecessarily fine or petty distinctions: To argue about whether they arrived at two o'clock or at 2:01 is just splitting hairs.|
|12.||tear one's hair, to manifest extreme anxiety, grief, or anger: He's tearing his hair over the way he was treated by them. Also, tear one's hair out.|
|13.||to a hair, perfect to the smallest detail; exactly: The reproduction matched the original to a hair.|
|14.||without turning a hair, without showing the least excitement or emotion. Also, not turn a hair.|
You Are a Haunted House
You are a deeply complicated and sometimes deeply disturbed person.
You can't help but be attracted to the dark side of life - even when it's pretty gruesome.
In relationships, you are honest and real. So real that it's definitely a little scary.
You don't fake it or play along just to get along. And people either respect this... or deeply resent it
Your life is thoughtful, deep, and even philosophical at times.
You see the world as it is. You don't sugar coat anything.
Facing and fighting your fears is important to you. You believe that too much of life is whitewashed.
You're not too morbid... you just believe that you can't enjoy life without exorcising a few demons first!
At your best, you are brave, intense, and fearless.
Not only do you face the abyss head on - you challenge your friends to do the same.
At your worst, you are depressed and morose.
If you're not careful, your thoughts take over your mind... and they aren't pretty!
Joseph Martin Luther Gardner was pronounced dead at 6:15 p.m. Friday in the state's death chamber in Columbia. He did not make a final statement, but did mouth the words "Thank you. I'm OK," to a relative who witnessed his death.
Gardner was convicted in the 1992 kidnapping, rape and slaying of 25-year-old Melissa "Missi" McLauchlin.
Police said Gardner and his co-defendants decided to kill a white woman as retribution for slavery. But the victim's family and Gardner's attorneys say they don't think the killing had anything to do with racial revenge. Source.
|1.||doubtfulness or uncertainty of meaning or intention: to speak with ambiguity; an ambiguity of manner.|
|2.||an unclear, indefinite, or equivocal word, expression, meaning, etc.: a contract free of ambiguities; the ambiguities of modern poetry.|

source: HuggingFaceFW/fineweb-edu


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I have a Lie algebra comprised of the generators $\{e_1,e_2,e_3,e_4\}$ for which the only non-zero commutators are
$$ [e_4,e_2]=-i e_3 $$ $$ [e_4,e_3]= i e_2 $$
(Excuse the physicist notation, for mathematicians the generators are actually ${ie_1,ie_2,ie_3,ie_4}$). Clearly, this is a solvable Lie Algebra ($[e_3,e_2]=0$).
My question is: Is there a simple way to refer to it without declaring its commutators? Like we can refer to $su(2)$ instead of writing out all of $su(2)$'s generators. I'd like to be able to do that for this algebra. If there's not a way to do this, I'd like to know that instead.
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What is the field? $\mathbb R$, $\mathbb C$ or any? I can't understand completely your notation. – emiliocba Jan 24 '12 at 19:32
Sorry, $\mathbb R$ is implied in physics, so that we get unitary evolution. However, $\mathbb C$ would be just the complexification of the analogous "real" algebra, no? – thequark Jan 25 '12 at 1:02
2 Answers 2
up vote 1 down vote accepted
Consider using the basis $$\{ f_1, f_2, f_3, f_4 \} = \{ e_1, i e_2 + e_3, e_2 + i e_3, e_4 \}$$ since all basis commutators are zero except for $$[f_4,f_2]=f_2 \quad [f_4,f_3]=-f_3$$
As emiliocba mentioned, the algebra is the direct product of a trivial one-dimensional algebra generated by $e_1=f_1$, and a three dimensional algebra generated by the other basis vectors.
According to wikipedia this three dimensional algebra is the Lie algebra of type Type VI0, the Lie algebra of the group of isometries of Minkowski space.
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Firt at all, your algebra $\mathfrak g$ can be written as $$ \mathfrak g=\mathfrak h\times \mathbb R, $$ where $\mathbb R$ is the generated space by $e_1$ and $\mathfrak h=\langle e_2,e_3,e_4\rangle$.
Now, $\mathfrak h$ is one of the infinite solvable Lie algebras of dimension three. Look at Exercice 2 of Chapter I of Knapp's book. I don't know if these algebras have a name.
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Charles Benedict DavenportArticle Free Pass
Charles Benedict Davenport, (born June 1, 1866, Stamford, Conn., U.S.—died Feb. 18, 1944, Cold Spring Harbor, N.Y.), American zoologist who contributed substantially to the study of eugenics (the improvement of populations through breeding) and heredity and who pioneered the use of statistical techniques in biological research.
After receiving a doctorate in zoology at Harvard University in 1892, Davenport taught there until 1899, when he left to join the faculty of the University of Chicago, where, from 1901 to 1904, he was curator of the zoological museum. He directed the department of genetics (1904–34) for the Station for Experimental Evolution at Cold Spring Harbor, N.Y., and also founded and directed the Eugenics Record Office (1910–34).
While teaching experimental morphology at Harvard, he used statistical methods in population studies. Partly as a result of breeding experiments with chickens and canaries, he was one of the first, soon after 1902, to recognize the validity of the newly discovered Mendelian theory of heredity. In Heredity in Relation to Eugenics (1911), he compiled evidence concerning the inheritance of human traits, on the basis of which he argued that the application of genetic principles would improve the human race.
Davenport was editor of Genetics (from 1916) and the Journal of Physical Anthropology (from 1918). Davenport's other important works include Statistical Methods with Special Reference to Biological Variation (1899), Eugenics (1910), and Body Build and Its Inheritance (1923).
What made you want to look up "Charles Benedict Davenport"? Please share what surprised you most...


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Bringing Them Home name index – Fact sheet 175
The National Archives of Australia holds many records that contain information about Aboriginal and Torres Strait Islander people and their history. The Archives has created an index of names that appear in the most relevant of these records in response to the recommendations of Bringing Them Home, the report of the National Inquiry into the Separation of Aboriginal and Torres Strait Islander Children from Their Families, released in 1997.
The Bringing Them Home (BTH) name index aims to help Indigenous people find information about themselves, their families and their country. The index contains:
- names of Aboriginal and Torres Strait Islander people
- names of non-Indigenous people related to or associated with Indigenous people
- names of missions and institutions where Aboriginal and Torres Strait Islander people were placed
- places where Aboriginal and Torres Strait Islander people have lived or visited
The index does not contain information about the people named. To see this information you will need to view the original records (files, papers and photographs) or photocopies of them.
Requesting a search of the BTH name index
On request, National Archives reference staff will search the index for you. To assist us to undertake a thorough search, it helps if you provide as many details as possible, including:
- name of the person you are researching – this includes any variations in the spelling of given names, nicknames, forgotten names, or Indigenous names
- family connections – the names of any siblings, children or other relatives
- language group, country or homeland – which were sometimes used to identify people
- place – where the person was born, lived, worked, or was sent to
- date of birth, age at events, or date of death of the person
- date ranges – year or period the person was in a certain place or area, such as the period they worked on a particular cattle station
- significant events that may have occurred in the person's life, such as being evacuated because of natural disaster or war
You may not be able to supply all of these details about the person you are seeking but, the more information you provide, the easier it will be for us to determine if there are references to the person or family you are researching in the Archives' holdings.
You can ask for the BTH name index to be searched by contacting the Archives' National Reference Service:
National Reference Service
National Archives of Australia
PO Box 7425
CANBERRA BC ACT 2610
Using information from the BTH name index to find records
If a search of the name index locates entries relating to the person you are researching, we will send you a list of the names found in the index. You will then be able to:
- ask for photocopies of the pages of the original records that mention the name, or
- view the records in the National Archives reading room of the office in which they are held
Reference officers will be able to advise you where the records are located.
In some instances the records may contain distressing or offensive information. The records were created many years ago and are written in the language of the day. Some personally sensitive information in the records is withheld from general access under the provisions of the Archives Act 1983.
If the reason for seeking access is to obtain information for the purpose of re-establishing family and community links, under the Memoranda of Understanding between the Archives and Northern Territory, Victorian and South Australian Indigenous communities you may look at information normally restricted from public access.
Record holdings on Aboriginal and Torres Strait Islander people
The BTH name index is not the only information resource available to researchers of Indigenous family history.
While most government records relating to Aboriginal affairs before 1970 were created and maintained by state governments, the National Archives holds large quantities of records relevant to Northern Territory and Victorian Indigenous people.
A number of fact sheets and guides to the Archives' records on Indigenous people are available.
The Victorian Koorie Records Taskforce, in association with the Public Record Office of Victoria, has developed 'Finding your story' website.


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What's the one sure-fire way to save an animal from extinction? Turn it into a pet, says Michael Archer, director of the Australian Museum in Sydney. With many of the country's native animals in serious trouble, he wants Australians to stop canoodling with dogs and cats and cuddle a quoll or a possum instead. Besides, says Archer, native animals are kinder to the environment-and a lot more fun. Stephanie Pain meets the man with a mission to make you love marsupials.
Why should Australians swap their traditional pets for native animals?
Australia is fundamentally different from every other continent and it's filled with unique animals. Since Europeans arrived, native species have been disappearing almost as fast as those obliterated by the last great mass extinction 65 million years ago. And what we lose here, the whole world loses. Traditional methods of conservation clearly aren't enough, so we have to explore...
To continue reading this article, subscribe to receive access to all of newscientist.com, including 20 years of archive content.


file_specification). The diskgroup_alias_clauses let you create more user-friendly alias names for the Oracle ASM filenames. You cannot specify an alias name that ends in a dotted pair of numbers, as this format is indistinguishable from an Oracle ASM filename.
Before specifying this clause, you must first create the directory structure appropriate for your naming conventions (see diskgroup_directory_clauses). The total length of the alias name, including the directory prefix, is limited to 256 bytes. Alias names are case insensitive but case retentive.
ADD ALIAS
Use this clause to create an alias name for an Oracle ASM filename. The alias_name consists of the full directory path and the alias itself. To determine the names of existing Oracle ASM aliases, query the V$ASM_ALIAS dynamic performance view. Refer to ASM_filename for information on Oracle ASM filenames.
DROP ALIAS
Use this clause to remove an alias name from the disk group directory. Each alias name consists of the full directory path and the alias itself. The underlying file to which the alias refers remains unchanged.
RENAME ALIAS
Use this clause to change the name of an existing alias. The alias_name consists of the full directory path and the alias itself.
Restriction on Dropping and Renaming Aliases
You cannot drop or rename a system-generated alias. To determine whether an alias was system generated, query the SYSTEM_CREATED column of the V$ASM_ALIAS dynamic performance view.
diskgroup_volume_clauses
Use these clauses to manipulate logical Oracle ASM Dynamic Volume Manager (Oracle ADVM) volumes corresponding to physical volume devices. To use these clauses, Oracle ASM must be started and the disk group being modified must be mounted.
See Also:
Oracle Automatic Storage Management Administrator's Guide for more information about disk group volumes, including examples
add_volume_clause
Use this clause to add a volume to the disk group.
For asm_volume, specify the name of the volume. The name can contain only alphanumeric characters and the first character must be alphabetic. The maximum length of the name is platform dependent. Refer to Oracle Automatic Storage Management Administrator's Guide for more information.
For size_clause, specify the size of the Oracle ADVM volume. The Oracle ASM instance determines whether sufficient space exists to create the volume. If sufficient space does not exist, then the Oracle ASM instance returns an error. If sufficient space does exist, then all nodes in the cluster with an Oracle ASM instance running and the disk group mounted are notified of the addition. Oracle ASM creates and enables on those nodes a volume device that can be used to create and mount file systems.
The following optional settings are also available:
 - In the redundancy_clause, specify the redundancy level of the Oracle ADVM volume. You can specify this clause only when creating a volume in a normal redundancy disk group. You can specify the following volume redundancy levels:
 - MIRROR: 2-way mirroring of the volume. This is the default.
 - HIGH: 3-way mirroring of the volume.
 - UNPROTECTED: No mirroring of the volume.
 You cannot specify the redundancy_clause when creating a volume in a high redundancy disk group or an external redundancy disk group. If you do so, then an error will result. In high redundancy disk groups, Oracle Database automatically sets the volume redundancy to HIGH (3-way mirroring). In external redundancy disk groups, Oracle Database automatically sets the volume redundancy to UNPROTECTED (no mirroring).
 - In the STRIPE_WIDTH clause, specify a stripe width for the Oracle ADVM volume. The valid range is from 4KB to 1MB, at intervals of the power of 2. The default value is 128K.
 - In the STRIPE_COLUMNS clause, specify the number of stripes in a stripe set of the Oracle ADVM volume. The valid range is 1 to 8. The default is 4. If STRIPE_COLUMNS is set to 1, then striping becomes disabled. In this case, the stripe width is the extent size of the volume. This volume extent size is 64 times the allocation unit (AU) size of the disk group.
 - In the disk_region_clause clause, specify the Intelligent Data Placement attribute of both the primary and nonprimary mirror of the disk group volume. The default for both is COLD. See disk_region_clause for details on this clause.
modify_volume_clause
Use this clause to modify the characteristics of an existing Oracle ADVM volume. You must specify at least one of the following clauses:
 - In the disk_region_clause clause, specify the Intelligent Data Placement attribute of both the primary and nonprimary mirror of the disk group volume. The default for the primary mirror is COLD. The default for mirror and high redundancy is HOT. See disk_region_clause for details on this clause.
 - In the MOUNTPATH clause, specify the mountpath name associated with the volume. The mountpath_name can be up to 1024 characters.
 - In the USAGE clause, specify the usage name associated with the volume. The usage_name can be up to 30 characters.
RESIZE VOLUME Clause
Use this clause to change the size of an existing Oracle ADVM volume. In an Oracle ASM cluster, the new size is propagated to all nodes. If an Oracle Automatic Storage Management File System (ACFS) exists on the volume, then you must use the acfsutil size command instead of the ALTER DISKGROUP statement.
See Also:
Oracle Automatic Storage Management Administrator's Guide for more information about the acfsutil size command
DROP VOLUME Clause
Use this clause to remove the Oracle ASM file that is the storage container for an existing Oracle ADVM volume. In an Oracle ASM cluster, all nodes with an Oracle ASM instance running and with this disk group open are notified of the drop operation, which results in removal of the volume device. If the volume file is open, then this clause returns an error.
diskgroup_attributes
Use this clause to specify attributes for the disk group. Table 13-2 lists the attributes you can set with this clause. Refer to the CREATE DISKGROUP "ATTRIBUTE Clause" for information on the behavior of this clause.
modify_diskgroup_file
Use this clause to modify the Intelligent Data Placement attributes of an existing disk group file. When you modify the Intelligent Data Placement for a file, this action will apply to new extensions of the file, but existing file contents are not affected until a rebalance operation. To apply the new Intelligent Data Placement policy for existing file contents, you can manually initiate a rebalance. A rebalance operation uses the last specified policy for the file extents.
See Also:
drop_diskgroup_file_clause
Use this clause to drop a file from the disk group. Oracle ASM also drops all aliases associated with the file being dropped. You must use one of the reference forms of the filename. Most Oracle ASM files do not need to be manually deleted because, as Oracle Managed Files, they are removed automatically when they are no longer needed. Refer to ASM_filename for information on the reference forms of Oracle ASM filenames.
You cannot drop a disk group file it if is the spfile that was used to start up the current instance or any instance in the Oracle ASM cluster.
convert_redundancy_clause
You can use this clause to convert a NORMAL REDUNDANCY or HIGH REDUNDANCY disk group to a FLEX REDUNDANCY disk group. The disk group must have at least three failure groups before you start the conversion.
usergroup_clauses
Use these clauses to add a user group to the disk group, remove a user group from the disk group, or to add a member to or drop a member from an existing user group.
See Also:
Oracle Automatic Storage Management Administrator's Guide for detailed information about user groups and members, including examples
ADD USERGROUP
Use this clause to add a user group to the disk group. You must have SYSASM or SYSDBA privilege to create a user group. The maximum length of a user group name is 63 bytes. If you specify the user name, then it must be in the OS password file and its length cannot exceed 32 characters.
MODIFY USERGROUP
Use these clauses to add a member to or drop a member from an existing user group. You must be an Oracle ASM administrator (with SYSASM privilege) or the creator (with SYSDBA privilege) of the user group to use these clauses. The user name must be an existing user in the OS password file.
DROP USERGROUP
Use this clause to drop an existing user group from the disk group. You must be an Oracle ASM administrator (with SYSASM privilege) or the creator (with SYSDBA privilege) of the user group to use this clause. Dropping a user group may leave a disk group file without a valid user group. In this case, you can update the disk group file manually to add a new, valid group using the file_permissions_clause.
user_clauses
Use these clauses to add a user to, drop a user from, or replace a user in a disk group.
Note:
When administering users with SQL*Plus, the users must be existing operating system users and their user names must have corresponding operating system user IDs. However, only users in the same cluster as the Oracle ASM instance can be validated.
ADD USER
Use this clause to add one or more operating system (OS) users to an Oracle ASM disk group and give those users


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Three samples of Schott Zerodur were recently measured using Jet Propulsion Laboratory's Cryogenic Dilatometer Facility. The initial purpose of these tests was to provide precision CTE measurements to help correlate thermomechanical models with the actual performance of NASA's Space Interferometry Mission (SIM) TOM-1C testbed. A total of six Zerodur test samples, as well as the SIM testbed mirror were machined from the same block of glass. Thermal strain as a function of time, sample temperature, and cooling rate were measured over a temperature range of 270K to 310K. Presented in this paper is a discussion of the sample configuration, test facilities, test method, data analysis, test results, and future plans.
Linear thermal expansion measurements of nine samples of Lead Magnesium Niobate (PMN) electroceramic material were recently performed in support of NASA's Terrestrial Planet Finder Coronagraph (TPF-C) mission. The TPF-C mission is a visible light coronagraph designed to look at roughly 50 stars pre-selected as good candidates for possessing earth-like planets. Upon detection of an earth-like planet, TPF-C will analyze the visible-light signature of the planet's atmosphere for specific spectroscopic indicators that life may exist there. With this focus, the project's primary interest in PMN material is for use as a solid-state actuator for deformable mirrors or compensating optics. The nine test samples were machined from three distinct boules of PMN ceramic manufactured by Xinetics Inc. Thermal expansion measurements were performed in 2005 at NASA Jet Propulsion Laboratory (JPL) in their Cryogenic Dilatometer Facility. All measurements were performed in vacuum with sample temperature actively controlled over the range of 270K to 310K. Expansion and contraction of the test samples with temperature was measured using a JPL-developed interferometric system capable of sub-nanometer accuracy. Presented in this paper is a discussion of the sample configuration, test facilities, test method, data analysis, test results, and future plans.
As part of the James Webb Space Telescope (JWST) materials working group, a novel cryogenic dilatometer was designed and built at NASA Jet Propulsion Laboratory to help address stringent coefficient of thermal expansion (CTE) knowledge requirements. Previously reported results and error analysis have estimated a CTE measurement accuracy for ULE of 1.7 ppb/K with a 20K thermal load and 0.1 ppb/K with a 280K thermal load. Presented here is a further discussion of the cryogenic dilatometer system and a description of recent work including system modifications and investigations.
The 2003 mission to Mars includes two Rovers, which will land on the Martian surface. Each Rover carries 9 cameras of 4 different designs. In addition, one similar camera is mounted to each lander assembly to monitor the descent and provide information for firing the control jets during landing. This paper will discuss the mechanical systems design of the cameras, including fabrication tolerances of the lenses, thermal issues, radiation shielding, planetary protection, detector mounting, electronics, the modularity achieved, and how the 10 different locations were accommodated on the very tight real estate of the Rovers and Landers.


text:
Abstract by Nancy Fulda
EVE: Emotive Adversarial Ensembles for Mixed Initiative Dialog
Machine learning researchers often represent dialog as a strict mapping from input text to output text, but psychological and cognitive science literature shows that humans consistently model each other during communicative processes. Building upon a dialogic view of conversation and working in conjunction with Amazon's Alexa Prize support team, we present EVE, a conversational AI architecture that treats communication as a cooperative effort between unique individuals. Rather than attempting to imitate a human, EVE embraces its identity as a synthetic being, actively seeking information to expand its world-view while still accessing live news streams, fact repositories, and other online APIs in response to user queries. By modeling the expectations of its conversation parter, EVE is able to respond to user utterances in meaningful ways. The completed system will compete against other university teams for a one million dollar grand prize.


code. CVS will tell you who last changed each line of code, and when they did it. The commit comment (hopefully) tells you why.
A commit message should contain, in order:
 - A couple of words indicating which part of moodle this change affects. For example 'forum backup', 'quiz attempting' or 'weblib'.
 - A tracker issue id like MDL-12345. (If necessary, create an issue before committing, the only exception is for very minor typos.)
 - A brief description of the problem you are fixing. (If you are feeling lazy, you may be able to get away with copying and pasting the issue summary from the tracker.)
 - If it is not immediately obvious, a brief summary of why this change fixes the problem. If a longer description is necessary, you may also want to add more information to the tracker issue, or Moodle Docs, but the code changes + commit message should provide enough clues to how the fix works on their own.
Here is an example of a commit message from a simple change:
user selection: MDL-17072 Polishing the role assign page: Do processing
before print_header in line with best practice.
Actually, the ideal commit message would be a bit shorter than that. It is good if the first three items (area of Moodle, tracker id and brief description) will fit in the subject line of an email message.
Here is an example from a bigger commit (would it have been better if this could have been done as several smaller commits?):
role overrides: MDL-17070 Improve override roles page to match the recent
usability improvements on the assign page.
MDL-11529 When assigning/overriding roles, the dropdown for switching to
another role should have a number in brackets
MDL-16549 Should not be able to edit the permission associated with
moodle/site:doanything on any role.
Here is an example of a commit (from a while ago, which is why the issue number is in the wrong place) with some explanation of the change:
accesslib: get_user_by_capability() - Handle complex rolecap resolution
With this patch, get_user_by_capability() can handle the cases where
users have multiple role assignments to the same course, and PREVENTs
and PROHIBITs affect the rolecaps of this course.
Without stored procedures we cannot resolve this entirely on the
server side - so in the complex cases we do as much as we can on SQL,
and post-process the data on the PHP side, including SQL-style
The CVS commits email list
You can subscribe at to this email list. You will then get an email every time someone commits a change to Moodle. This is a good way to keep track of what is going on, and also a good way to learn best-practice for CVS commit messages.
You probably want to set your mail client to automatically move messages from this list into a separate mail folder. You may not want to remain subscribed all the time, but when you are new to the project, it is a great way to do a bit of social-constructionist peer learning about our use of CVS.
Working with branches
This diagram shows how the main moodle module branches into different versions over time.
CVS tree
To see all the current tags and branches that are available, use this command on any old file (such as index.php in the top moodle directory):
 cvs status -v index.php
Some tagging guidelines:
 - Tag and branch names should always be all upper-case.
 - Tags and branches should ALWAYS be applied to the entire module (all of Moodle). Don't tag individual files or directories.
 - We don't allow renaming of tags because people may be relying on them, so get them right the first time!
Trunk development
The Trunk of CVS is the main development version of Moodle. In CVS it is also known as the HEAD, or default branch.
Moodle developers try to keep this stable as possible, but as it usually contains new code it probably has bugs and small instabilities.
Every now and then we decide the product has enough features to make a release. At this time, the trunk is tagged with a MOODLE_XX_BETA tag (in case we ever want to roll back to that point) and a new branch is formed for the release, called MOODLE_XX_STABLE.
A Beta package is also released at this point - it's for testers who don't use CVS but want to test the latest features and report bugs.
Stable branches for each release
As soon as the stable branch MOODLE_XX_STABLE is created, development efforts will fork into two streams for a while. Some people may continue working on new features in the trunk for the next release, but most developers should be concentrating on using the current STABLE branch and fixing bugs that are found in it.
You can switch your local copy of Moodle to the STABLE version using the following command in Unix from the root directory:
 cvs update -dP -r MOODLE_XX_STABLE
After that, all the commands described above will apply to that stable version. To return to the trunk version just issue:
 cvs update -dPA
On Windows clients you should have a menu from which you can choose the branch.
Once the new STABLE branch really stabilises, a release can be declared. Packages are created for distribution and the branch will be tagged (by Martin Dougiamas) with a tag named: MOODLE_XXX
Merging fixes
All bug fixes in any STABLE branch should be merged back into the trunk so that they become available in future versions of Moodle. A floating tag called MOODLE_XX_MERGED needs to be maintained to keep track of the last merge. The procedure for such a merge is as follows (I'm using CVS on the Unix command line but the steps are the same for any CVS client):
This diagram summarises the process
1. I highly recommend keeping one checked out copy of each stable branch and the trunk/head version locally to make it easier to jump between them. Set them all up as virtual web sites on your development machine. I use directories like /moodle/18, /moodle/19 /moodle/dev etc.
2. Update to the latest stable version (I'll use XX in the example but it could be 18, 19 etc) for the relevant files, and do a cvs diff just to double-check exactly what you are checking in. Note you only need to update the files/directories you are working in, but sometimes it help to update everything anyway just to do a final check on the functionality using the web.
 cd /moodle/XX/user
 cvs update -dPA
 cvs diff -c file1.php file2.php
3. If all looks OK, check in the fix to the stable branch. Make sure that the commit message contains the bug tracker ID (eg MDL-1111) and a decent description of your thoughts on the fix. If you don't specify a message in the command line, you'll be put into an editor to type one.
 cvs commit -m "MDL-1234 Corrected a small typo in the user name field" file1.php file2.php
4. Go to the very latest trunk version and make sure it's up-to-date.
 cd /moodle/dev/user
 cvs update -dPA
5. Merge everything into your local copy of the trunk from your stable branch since the last merge. You can use the same sequence of (4) and (5) to merge the changes into other stable branches too (to backport the fix to the previous stable versions).
 cvs update -kk -j MOODLE_XX_MERGED -j MOODLE_XX_STABLE file1.php file2.php
6. Carefully watch the update logs for conflicts, and fix every file that you see with a conflict. Afterwards, it may help to just run a diff to make sure the result is what you expected:
 cvs diff -c file1.php file2.php
7. Check your merged local copy back into CVS trunk version
 cvs commit -m "MDL-1234 Corrected a small typo in the user name field, merged from XX" file1.php file2.php
8. Go back to your branch version
 cd /moodle/XX/user
9. Update the floating merge tag for the affected files (so that it matches MOODLE_XX_STABLE) so that this process can be repeated next time
 cvs tag -F MOODLE_XX_MERGED file1.php file2.php
Finally, the values for $version in all the Moodle version.php files within the stable branch should not be updated at all if possible (except the last digit if absolutely necessary). The reason is that someone updating from a very stable version to the next very stable version could miss database upgrades that happened on the trunk.
In other words, if you have changes to the database schema to commit to a stable branch, please check with Martin Dougiamas, or one of the other core Moodle developers.
Sometimes you fix something in a branch that needs to be "backported" to an earlier branch. This is often the case with security fixes. The procedure is exactly the same as described above, except you apply your changes backward instead of forward (to previous versions instead of HEAD). Here is a summary, using the steps described above. The scenario is that you have a fix in MOODLE_19_STABLE that needs backporting to MOODLE_18_STABLE, but NOT to HEAD (the problem you are fixing


Difference Wiki
Logical Address vs. Physical Address: What's the Difference?
Edited by Huma Saeed || By Sumera Saeed || Updated on October 25, 2023
A logical address is generated by a CPU during a program's execution, while a physical address refers to a location in a computer's memory hardware.
Key Differences
A logical address is created and used by a Central Processing Unit (CPU) when a program is being executed. This address, often called a virtual address, represents a location from the program's perspective. On the other hand, a physical address pertains to the actual hardware memory location in the system, where data or instructions are stored.
Sumera Saeed
Oct 25, 2023
The concept of a logical address is crucial for systems that utilize virtual memory. Such systems allow programs to run as if they have access to a larger memory space than what's physically available. Contrarily, the physical address ensures that the system knows where exactly in the memory the required data or instruction is located.
Sumera Saeed
Oct 25, 2023
Mapping between a logical address and a physical address is commonly achieved using memory management techniques, such as paging or segmentation. This mapping ensures that even if a program thinks it's accessing a specific location (logical address), the system redirects it to the correct physical address where the content is actually stored.
Sumera Saeed
Oct 25, 2023
Logical addresses ensure a level of abstraction, providing flexibility and security. It allows programs to operate without needing to know physical memory details. Conversely, physical addresses provide the concrete locations within the hardware where the system reads or writes data.
Sumera Saeed
Oct 25, 2023
The distinction between logical address and physical address is fundamental in modern computer systems. While the logical address offers a program's perceived memory location, the physical address pinpoints the actual hardware location where that piece of data or instruction resides.
Sara Rehman
Oct 25, 2023
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Comparison Chart
Definition
Address generated by CPU during a program's execution
Actual location in computer's memory hardware
Sumera Saeed
Oct 25, 2023
Purpose
Provides abstraction for program execution
Specifies exact location of data in memory hardware
Sumera Saeed
Oct 25, 2023
Usage
Employed in systems with virtual memory
Used by memory hardware to access data
Sumera Saeed
Oct 25, 2023
Dependency
Relies on mapping mechanisms to convert to physical addresses
Independent and directly corresponds to hardware
Sumera Saeed
Oct 25, 2023
Security and Flexibility
Offers abstraction for enhanced security and flexibility
Provides direct, unabstracted hardware access
Sumera Saeed
Oct 25, 2023
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Logical Address and Physical Address Definitions
Logical Address
Represents a program's perspective of memory.
From the program's view, it accesses data at a logical address.
Sumera Saeed
Oct 25, 2023
Physical Address
A physical address refers to a specific location in memory hardware.
The data is stored at the physical address 0x1A2B in RAM.
Huma Saeed
Oct 25, 2023
Logical Address
A logical address is a virtual memory location used by programs.
The program uses the logical address to reference its data.
Huma Saeed
Oct 25, 2023
Physical Address
Represents the tangible storage location in a computer system.
The cache memory fetched the data from the designated physical address.
Sara Rehman
Oct 25, 2023
Logical Address
It provides an abstract view of memory for programs.
The program, unaware of the actual memory layout, uses the logical address.
Sumera Saeed
Oct 25, 2023
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Physical Address
It's the actual memory location of data or instructions.
The CPU retrieves instructions from a given physical address.
Sumera Saeed
Oct 25, 2023
Logical Address
Logical addresses need mapping to access actual memory.
The memory management unit maps the logical address to a physical one.
Sara Rehman
Oct 25, 2023
Physical Address
Directly accessed by the memory hardware without abstraction.
The memory chip uses the physical address to read or write data.
Sumera Saeed
Oct 25, 2023
Logical Address
Logical addresses are generated by the CPU during program execution.
The CPU creates a logical address for each memory request.
Sumera Saeed
Oct 25, 2023
Physical Address
It's where the content specified by logical address resides.
The logical address maps to a specific physical address in the memory.
Sara Rehman
Oct 25, 2023
FAQs
Why is the distinction between logical address and physical address important?
It allows for abstraction in memory management, enhancing flexibility and security.
Sumera Saeed
Oct 25, 2023
How is the conversion from logical address to physical address achieved?
Through memory management techniques like paging or segmentation.
Aimie Carlson
Oct 25, 2023
Do all computer systems use both logical and physical addresses?
Most modern systems do, especially those utilizing virtual memory.
Aimie Carlson
Oct 25, 2023
How does a computer system use a physical address?
A physical address is used to pinpoint the exact hardware location in memory to access data.
Huma Saeed
Oct 25, 2023
Is a logical address the same as a virtual address?
Yes, a logical address is often referred to as a virtual address.
Sumera Saeed
Oct 25, 2023
Can a program directly access the physical address?
Typically, programs deal with logical addresses, and the system handles the mapping to physical addresses.
Aimie Carlson
Oct 25, 2023
What's the main purpose of a logical address?
A logical address provides an abstract memory location for program execution.
Sumera Saeed
Oct 25, 2023
Is the range of logical addresses the same as physical addresses?
Not always. Logical address space can be larger than physical address space due to virtual memory.
Aimie Carlson
Oct 25, 2023
What happens when the logical address space exceeds physical address space?
Portions of memory can be swapped between RAM and storage devices to manage the discrepancy.
Aimie Carlson
Oct 25, 2023
Why is abstraction through logical addressing beneficial?
It offers security, flexibility, and allows programs to operate without knowing actual memory details.
Sumera Saeed
Oct 25, 2023
In a memory hierarchy, where are physical addresses primarily used?
Physical addresses are used at the lower levels of memory hierarchy like RAM and caches.
Harlon Moss
Oct 25, 2023
What happens if the mapping from logical to physical address fails?
It may result in a page fault, prompting the system to fetch the required data from secondary storage.
Harlon Moss
Oct 25, 2023
Do operating systems manage the mapping between logical and physical addresses?
Yes, OSes play a crucial role in managing memory and address mapping.
Harlon Moss
Oct 25, 2023
Can users or programmers directly modify the physical address space?
Direct modification of physical address space by users is usually restricted to ensure system stability and security.
Sumera Saeed
Oct 25, 2023
Do logical addresses always map to the same physical addresses?
No, the mapping can change, especially in systems with dynamic memory management.
Aimie Carlson
Oct 25, 2023
What role does the Memory Management Unit (MMU) play regarding addresses?
The MMU is responsible for converting logical addresses to physical addresses.
Janet White
Oct 25, 2023
Are logical addresses continuous?
Not necessarily. With techniques like paging, non-contiguous logical addresses can map to contiguous physical addresses.
Harlon Moss
Oct 25, 2023
Can multiple logical addresses map to a single physical address?
Typically, one logical address maps to one physical address, but reverse isn't always true.
Sumera Saeed
Oct 25, 2023
In embedded systems, how common is the use of logical addresses?
Embedded systems often work directly with physical addresses due to their specific and optimized nature.
Harlon Moss
Oct 25, 2023
Can memory access speeds differ based on logical or physical addressing?
Yes, accessing data through logical addresses (which require mapping) can introduce slight delays compared to direct physical addressing.
Sumera Saeed
Oct 25, 2023
About Author
Written by
Sumera Saeed
Sumera is an experienced content writer and editor with a niche in comparative analysis. At Diffeence Wiki, she crafts clear and unbiased comparisons to guide readers in making informed decisions. With a dedication to thorough research and quality, Sumera's work stands out in the digital realm. Off the clock, she enjoys reading and exploring diverse cultures.
Edited by
Huma Saeed
Huma is a renowned researcher acclaimed for her innovative work in Difference Wiki. Her dedication has led to key breakthroughs, establishing her prominence in academia. Her contributions continually inspire and guide her field.
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How Does Subaru EyeSight Work?
In recent years, carmakers have increasingly automated their safety systems. They've also added advanced features like blind-spot monitoring and rear cross-traffic alerts to even their base models. For example, Subaru introduced its EyeSight system in 2008 and has continued to improve it.
Here's everything you need to know about Subaru's advanced driver-assist system.
What is Subaru EyeSight?
RELATED: Subaru Didn't Overlook 1 of the Most Important Safety Features a Car Can Have
Subaru EyeSight began as the first safety platform using a dual-camera setup. Today, EyeSight offers a high-tech alert system that anticipates danger by watching the road with an extra set of eyes. Those extra eyes are, in fact, two color cameras tucked behind the rearview mirror. Subaru says they operate in stereo to provide onboard computers with a 3D view of the road and cars ahead.
As EyeSight technology continues to evolve, it also adds more safety features. In fact, 2021 Subaru models equipped with EyeSight get a whole suite of driver aids. They include adaptive cruise control, lane-keep assist, sway warning, pre-collision braking, pre-collision throttle management, and more.
How does Subaru EyeSight work?
EyeSight's two cameras continually scan the road for unexpected dangers by creating a 3D view of what lies ahead. So, how do the cameras' inputs work with the system?
Subaru's adaptive cruise control uses the cameras' inputs to keep a user-defined distance from the car in front. Because of EyeSight, the brand's adaptive cruise control works in slow-speed stop-and-go traffic and on interstate highways.
Also, lane-keep assists and sway warning features use EyeSight to determine where the lane's edge begins and ends. The system can provide corrective steering to nudge the vehicle back into its lane unless it detects the lane-change signal. You can easily override the steering inputs to change lanes.
Additionally, EyeSight provides input to the pre-collision braking and pre-collision throttle control systems whenever it detects an imminent collision. Pre-collision throttle control reduces engine power. It also provides more time for braking if you don't lift your foot off the gas. And pre-collision braking can initiate emergency braking with or without your input. Sometimes a fraction of a second can be the difference between a collision and a close call.
Is EyeSight available on all Subaru models?
Subaru EyeSight is available on only two of the WRX's four trims. But it comes with all 2021 models.
For an extra $845, EyeSight is an option on 2021 Impreza and Crosstrek models equipped with a continuously variable transmission. Of course, the CVT also adds $1,350 over the standard transmission.
EyeSight also comes standard on all 2021 Forester, Legacy, Outback, and Ascent models.
Does it live up to the hype?
In 2018, the Insurance Institute for Highway Safety's Highway Loss Data Institute conducted a study with interesting results. It shows Subaru vehicles equipped with pedestrian avoidance systems such as EyeSight had 35 percent fewer insurance claims for pedestrian collisions.
Considering vehicle-pedestrian collisions killed nearly 6,000 people in 2016, $2,200 is a small price to pay to improve your chances of avoiding one. And because it also prevents other collisions, Subaru EyeSight is worth the hype.


text:
Ferric Carboxymaltose (FCM) is widely used in the treatment of anaemia of Chronic Kidney Disease (CKD). The clinicians must be alert of the rare adverse events such as hypersensitivity with subsequent doses of Ferric carboxymaltose. Here, we report a case of a 59-year-old male a known case of CKD, with anaemia and thrombocytopenia. Ferric carboxymaltose was the treatment of choice. There was a hypersensitivity reaction to the second dose whereas, the first dose was well tolerated. This case report indicates the onset of adverse reaction with ferric carboxymaltose with the second dose even though the first dose was well tolerated.
All Science Journal Classification (ASJC) codes
- Clinical Biochemistry


How does 'going and coming' affect a workers' compensation claim?
| Apr 9, 2020 | Firm News |
If you sustain an injury in an automobile collision while performing a job-related task in New Jersey, you are usually eligible for workers' compensation, even if you are not driving a company vehicle.
Yet, it is not always a black-and-white issue, mainly when your accident happened during your commute or after hours. According to FindLaw, although you might consider commuting to be work-related, the 'going and coming' rule exempts daily travel from home to a job from workers' compensation claims. However, there are circumstances in which this rule may not apply:
Traveling between job locations
Your everyday duties may take you beyond one central workplace. This could apply if you are, for example, an on-site repair technician or a district manager that oversees several locations. In this case, the time you spend traveling from one place to another is job-related and thus covered by workers' compensation.
Driving by job definition
If you spend your entire shift in a vehicle, like a truck driver or law enforcement officer, then your car or truck could serve as your "workplace" and workers' compensation should cover any injury that occurs during your duties. It may complicate the situation if you are a traveling salesperson, for instance, and drive directly from your home in your personal car to all of your appointments. Some may consider the first leg to be a commute; some might argue that it is work-related.
Employer-assigned errands or special events
When your employer assigns you a "special mission," be it before, during or after your shift, workers' compensation rules usually classify it as job-related. Additionally, it does not usually matter if your boss asks you to pick up office supplies or his or her child from daycare. Furthermore, when you attend a work-related function outside of regular working hours like a company party or gathering, you could receive workers' compensation for an injury received during the event.
Out-of-town travel
If you travel out of town to do your work, the entire time you are away from home typically falls under job-related jurisdiction. Therefore, your drive from your home to the airport may or may not qualify for a workers' compensation claim, but once you are on the airplane, generally speaking, you are "on-the-job."


text:
American Heritage® Dictionary of the English Language, Fourth Edition
- n. A dark green fecal material that accumulates in the fetal intestines and is discharged at or near the time of birth.
Century Dictionary and Cyclopedia
- n. Poppy-juice.
- n. The feces of a new-born infant.
- n. In entomology, the feces of an adult insect just transformed from the pupa.
- n. medicine A dark green mass, the contents of the fetal intestines during the later stages of mammalian gestation, that forms the first faeces of the newborn
- n. obsolete opium
GNU Webster's 1913
- n. obsolete Opium.
- n. The contents of the fetal intestine; hence, first excrement.
- n. thick dark green mucoid material that is the first feces of a newborn child
- From Latin mēcōnium ("opium; excrement of a newborn child"), from Ancient Greek μηκώνιον ("poppy-juice, opium"), from μήκων ("poppy"). (Wiktionary)
- Latin mēcōnium, poppy juice, from Greek mēkōnion, from mēkōn, poppy. (American Heritage® Dictionary of the English Language, Fourth Edition)
"Sometimes the meconium can become impacted within the rectum or small colon of foals -- thus, the term meconium impaction."
"However, newborn infants produce this stuff called meconium which is like fecal tar."
"The belief is that suctioning prevents the baby from inhaling meconium, thereby preventing breathing problems or a rare type of pneumonia called meconium aspiration syndrome."
"Fetal defecation isn't normal, but fetuses do accumulate a mass of greenish feces, called meconium, in their intestines."
"Fetuses take amniotic fluid into their lungs, and in a minority of MSAF cases, passed meconium enters the airway before birth and afterward leads to respiratory symptoms collectively called meconium aspiration syndrome MAS."
"This blackish mixture, called meconium, will become her first bowel movement."
"This is called meconium and is a sign that the baby has passed his or her first stool (bowel movement)."
"Also, babies do NOT have a bowel movement (meconium) in utero unless baby is in distress, known as meconium aspiration syndrome."
"a little later, but in all cases during the first day; and this excrement is unduly copious in comparison with the size of the child; it is what the midwives call the meconium or"
"Researchers will also take biological samples from mothers -- and from newborns from birth through two years of age -- including blood, saliva, breast milk, urine, umbilical cord and placental material and "meconium," a baby's first stool, in which toxins may have accumulated over time."
These user-created lists contain the word 'meconium'.
A list of words that are odd or words that I have looked up.
"Luciferous Logolepsy is a collection of over 9,000 obscure English words. Though the definition of an 'English' word might seem to be straightforward, it is not. There exist so many adopted, deriv...
originally started as an attempt to collect words I found visually and auditorially beautiful, as well as psychically evocative, this has become nothing more than a grab bag of word curiosities, a...
Hecko, words! I'm so happy I've found you. I want to keep you all and never want to lose you again. I hope you like it here.
For double the fun, see also Congenital Conditions.
Interesting words you probably won't hear in your day-to-day.
Words that I do not know or unsure for toefl
Words that describe poo *very specifically*.
Looking for tweets for meconium.


text:
To perform clustering or similarity searches on trajectories of moving objects, an appropriate definition of the distance (or similarity) between two trajectories is important. Typically, the trajectory of a moving object is represented as a sequence of consecutive locations in a twoor three-dimensional space, in contrast to the one-dimensional case, which is common in timeseries databases [33, 52]. In addition, distances for moving object trajectories should be robust to outliers since measurements in mobile environments are noisy and the movement of objects may contain "gaps." Some distance measures proposed for moving object trajectories are investigated below.
For example, consider two trajectories of moving objects on the (x, y)-plane given as A = ((ax,1, ay,1),…, (ax,n, ay,n)) and B = ((bx,1, by,1),…, (bx,m, by,m)). Their lengths are n and m, respectively. When n = m, we can apply the Euclidean distance (L2 distance), which is simple and also the most popular:
Although the Euclidean distance can be evaluated efficiently, it cannot be applied when two trajectories have different lengths.


Back to Woods Hole Oceanographic Institution's Homepage
 - Connect with WHOI:
true expositive en-US Lonny Lippsett WHOI
What Other Tales Can Coral Skeletons Tell?
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In 2003, we traveled by ship to the New England Seamounts—a chain of extinct, undersea volcanoes about 500 miles off the East Coast of North America—to help collect dead corals that have been on the bottom of the ocean for thousands of years. For scientists, these corals are like deep-sea time machines.
As they grew, the skeletons of these long-living corals incorporated trace chemicals from surrounding seawater. By analyzing chemical variations in the corals' annual growth bands, our colleagues, geochemist Jess Adkins of the California Institute of Technology and Laura Robinson of Woods Hole Oceanographic Institution, are reconstructing the history of how ocean and climate conditions have changed over Earth's history. (See "The Coral-Climate Connection.")
But as we pulled corals from the sea, we began to wonder if we could go one step further and unlock the genetic makeup of these fossil coral species. Perhaps they could tell us the story of how deep-sea coral populations evolved over thousands of years—in response to the ocean and climate shifts that their skeletons are recording. Accomplishing this, however, means achieving something never done before: extracting DNA from these long-dead organisms.
A new line of inquiry
Tapping into the corals' ancient genetic record could let us see how populations adapted to changes in their environment over time. We would be able to determine if, and when, they moved among different seamounts at specific periods in history. We could also learn if populations preferred living at one depth or another at different times in history.
By matching genetic information with the dates of climate events recorded in their skeletons, we would determine whether populations migrated away from particular seamounts at times when the climate and ocean warmed or cooled, or if the populations were vastly reduced to a few survivors. All of this would give us the first insights into how corals were reacting to climate changes as far back as 100,000 years ago.
Unlocking genetic data from coral skeletons opens up a completely new avenue of coral and climate research. If successful, it would be possible to use these methods to extract genetic data from other dead coral populations worldwide. These techniques could be used, for example, to advance understanding of shallow-water coral reefs that died because of periodic ocean water warming associated with El Niño events.
It could also be possible to apply these techniques to other fossilized marine species, including clams, mussels, and snails from hydrothermal vents, to determine how they evolved through time. (See "The Evolutionary Puzzle of Seafloor Life.")
Coral collecting on the seafloor
The corals we study, called scleractinians or stony corals, have been living for about 250 million years throughout the world's oceans, from polar to tropical regions. We're interested in two species, Desmophyllum dianthus and Lophelia pertusa, which survive in sunless areas of the ocean up to 4,000 meters (2.5 miles) deep by filtering krill, copepods, and other tiny food particles drifting through the water column.
During three expeditions—one in 2003 with Adkins, and two more in 2005—we gathered several thousand dead scleractinian corals from 15 different seamounts. On two expeditions, we collected corals using the WHOI-operated submersible Alvin; on one, we used the remotely operated vehicle Hercules, operated by University of Rhode Island.
Operators of both vehicles gathered the samples by placing nets in the vehicles' robotic claws and sweeping them over the seafloor. They collected hundreds of fossil corals, ranging in size from tennis balls to volleyballs, in each sweep of the net. In other areas of the seafloor, dozens of dead corals were stuck together on overhangs, so the vehicles could simply snap off large pieces and bring them back to the surface.
Onboard the research vessels, we made detailed notes about the corals' appearances, took photographs, and then sorted, cleaned, and froze them. We also assembled digital data—maps, photo, and video documentation, and information about environmental conditions in which we found them, such as temperature, salinity, and current speed.
Avoiding contamination
Sensitive methods are required for analysis in long-dead coral samples, because DNA doesn't stick around forever. Unless samples are kept at a constant cold temperature, or are preserved properly, DNA degrades very quickly over time.
Fortunately, the corals we study lived and died in deep, cold water—and were protected by sediments—so we theorized that there would be a high likelihood that DNA remained within the skeleton. We were right.
Still, challenges remain. Familiar methods used routinely to extract genetic information are not sensitive enough for the small amounts of DNA left in dead coral skeletons. Also, not all the corals we collected will still contain DNA; some will have degraded. So we have to try a variety of methods to determine what works best. Even the most accomplished ancient DNA studies have only a 25 percent success rate with their samples.
There are few marine population studies using ancient DNA, and this project is among the first studies of ancient marine invertebrates. However, we are not the first scientists to extract ancient DNA from long-dead organisms. Scientists have extracted DNA from extinct land-dwelling animals, such as bison, woolly mammoths, and musk ox, some dating back 30,000 years. Researchers have also revealed how genetic populations have changed through time for species of trees, shrubs, mosses, and herbs, some as old as 400,000 years.
Work by these scientists has shown us that the DNA extraction methods must be exact, because the risk of contamination is huge. A random strand of hair or a stray speck of skin could throw off the results. Even paper is not allowed in ancient DNA laboratories, because the DNA contained in paper—previously living trees—could ruin samples undergoing analyses.
Trial and error
In April 2006, Rhian spent two weeks at the Paleo-DNA Laboratory at Lakehead University in Thunder Bay, Canada, which specializes in pinpointing methods for this type of specialized work. They had never done work on corals, so they were excited to help us refine our methods. Getting the optimal mix of chemicals and processes has been the result of time-consuming trial and error. All the testing has been worth it, though. We now have ever-improving methods to extract DNA and can concentrate on the project's larger goals.
The genetic data from the corals will be combined with Adkins' coral age and climate data to make correlations between the two. Then we will draw conclusions about what happened deep in the oceans, during past climate changes, and even make predictions about the future, including what will happen to deep-water corals (and the many animals that live on them) if the climate changes.
This project was funded by the WHOI Ocean Life and Ocean Climate Change Institutes. Research cruises were supported by the National Science Foundation and the NOAA Ocean Exploration Program.
Article images (4)
The Importance of Deep-sea Corals
With WHOI deep-sea biologist Tim Shank.
Articles Featuring
Biology Dept.


Crime and Religion
Search Learning Modules:
Many authors have written on the relationships between religion, crime, and deviance (e.g., Stark and Bainbridge�s Religion, Deviance and Social Control). Does religion help prevent individuals from committing crimes? How does religion shape people�s perceptions of crime and deviance? How does it affect views on punishments for crimes? These are the types of questions other sociologists have asked, and these are the type of questions you will explore in the following exercise.
Estimated time to complete: 30 minutes.
Skills Utilized
 - Interpreting maps and tables
 - Hypothesis testing
 - Self-directed analyses
 - Download the Word document
 Download the PDF file


DataDOMEventObject Interface
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DataDOMEventObject Interface (Microsoft.Office.Interop.InfoPath.SemiTrust)
An event object that is used during Microsoft Office InfoPath 2007 data validation events.
Namespace: Microsoft.Office.Interop.InfoPath.SemiTrust
Assembly: Microsoft.Office.Interop.InfoPath.SemiTrust (in
public interface DataDOMEventObject : DataDOMEvent, DocActionEvent, DocReturnEvent,
The DataDOMEvent object provides a number of properties and a method that can be used within a data validation event to programmatically interact with the data that is being validated and to provide a response if the data is not valid.
The DataDOMEvent object is passed as a parameter to the OnBeforeChange, the OnValidate, and the OnAfterChange events
The OnValidate event can occur without a change in the form's underlying XML document.
The DataDOMEvent object is used to get information about the XML Document Object Model (DOM) node that is being changed, and it also provides a property for getting a reference to a form's underlying XML document. In addition, it provides properties for handling the change in data, including rejecting the change and creating an error message.
The DataDOMEvent object is passed as an argument to one of the data validation event handlers. Its properties and method are only available during the event that it is passed to.
In the following example, the DataDOMEvent object is used to check the value of the node using the Site property. If the data validation fails, the ReportError method is used to create a custom error.
[InfoPathEventHandler(MatchPath="/my:myFields/my:field1", EventType=InfoPathEventType.OnValidate)]
public void field1_OnValidate(DataDOMEvent e)
if(e.Site.text!= "")
 int quantity = int.Parse(e.Site.text.ToString());
 if(quantity > 50)
 e.ReportError(e.Site, "Invalid quantity. The total number of each type of block cannot exceed 50.", false, "", 2,"modeless");
 if(quantity < 0)
 e.ReportError(e.Site, "Invalid quantity. The total number of each type of block cannot be less than 0.", false,"", 2,"modeless");
© 2015 Microsoft


text: OBJECTIVE: Quercetin, a commonly occurring flavonoid and well known antioxidant, has been suggested to possess other beneficial activities. The present study investigated the possible anti-inflammatory effects of physiologically attainable quercetin concentrations. METHODS: The effects of quercetin were tested in vitro, i.e., added to blood in the test tube, and ex vivo and in vivo, i.e., in blood taken after 4 wk of administration of quercetin in an intervention study. RESULTS: Quercetin dose-dependently inhibited in vitro lipopolysaccharide-induced tumor necrosis factor-alpha production in the blood of healthy volunteers. At a concentration of 1 muM, quercetin caused a 23% reduction. The in vitro lipopolysaccharide-induced interleukin-10 production remained unaffected by quercetin. A 4-wk quercetin intervention resulted in a significant increase in plasma quercetin concentration. The supplementation also increased total plasma antioxidant status but did not affect glutathione, vitamin C, and uric acid plasma concentrations. Basal and ex vivo lipopolysaccharide-induced tumor necrosis factor-alpha levels were not altered by the intervention. CONCLUSION: The present study shows that quercetin increases antioxidant capacity in vivo and displays anti-inflammatory effects in vitro, but not in vivo or ex vivo, in the blood of healthy volunteers. This lack of effect is probably due to their low cytokine and high antioxidant levels at baseline, indicating that neither inflammation nor oxidative stress is present. Only in people with increased levels of inflammation and oxidative stress, e.g., patients with a disease of which the pathology is associated with these two processes, might antioxidant supplementation be fruitful.