git-fetch-pack
GIT-FETCH-PACK(1) Git Manual GIT-FETCH-PACK(1)
NAME
 git-fetch-pack - Receive missing objects from another repository
SYNOPSIS
 git fetch-pack [--all] [--quiet|-q] [--keep|-k] [--thin] [--include-tag]
 [--upload-pack=<git-upload-pack>]
 [--depth=<n>] [--no-progress]
 [-v] <repository> [<refs>...]
DESCRIPTION
 Usually you would want to use git fetch, which is a higher level
 wrapper of this command, instead.
 Invokes git-upload-pack on a possibly remote repository and asks it to
 send objects missing from this repository, to update the named heads.
 The list of commits available locally is found out by scanning the
 local refs/ hierarchy and sent to git-upload-pack running on the other
 end.
 This command degenerates to download everything to complete the asked
 refs from the remote side when the local side does not have a common
 ancestor commit.
OPTIONS
 --all
 Fetch all remote refs.
 --stdin
 Take the list of refs from stdin, one per line. If there are refs
 specified on the command line in addition to this option, then the
 refs from stdin are processed after those on the command line.
 If --stateless-rpc is specified together with this option then the
 list of refs must be in packet format (pkt-line). Each ref must be
 in a separate packet, and the list must end with a flush packet.
 -q, --quiet
 Pass -q flag to git unpack-objects; this makes the cloning process
 less verbose.
 -k, --keep
 Do not invoke git unpack-objects on received data, but create a
 single packfile out of it instead, and store it in the object
 database. If provided twice then the pack is locked against
 repacking.
 --thin
 Fetch a "thin" pack, which records objects in deltified form based
 on objects not included in the pack to reduce network traffic.
 --include-tag
 If the remote side supports it, annotated tags objects will be
 downloaded on the same connection as the other objects if the
 object the tag references is downloaded. The caller must otherwise
 determine the tags this option made available.
 --upload-pack=<git-upload-pack>
 Use this to specify the path to git-upload-pack on the remote side,
 if is not found on your $PATH. Installations of sshd ignores the
 user's environment setup scripts for login shells (e.g.
 .bash_profile) and your privately installed git may not be found on
 the system default $PATH. Another workaround suggested is to set up
 your $PATH in ".bashrc", but this flag is for people who do not
 want to pay the overhead for non-interactive shells by having a
 lean .bashrc file (they set most of the things up in
 .bash_profile).
 --exec=<git-upload-pack>
 Same as --upload-pack=<git-upload-pack>.
 --depth=<n>
 Limit fetching to ancestor-chains not longer than n.
 git-upload-pack treats the special depth _PHONE_ as infinite
 even if there is an ancestor-chain that long.
 --shallow-since=<date>
 Deepen or shorten the history of a shallow repository to include
 all reachable commits after <date>.
 --shallow-exclude=<revision>
 Deepen or shorten the history of a shallow repository to exclude
 commits reachable from a specified remote branch or tag. This
 option can be specified multiple times.
 --deepen-relative
 Argument --depth specifies the number of commits from the current
 shallow boundary instead of from the tip of each remote branch
 history.
 --no-progress
 Do not show the progress.
 --check-self-contained-and-connected
 Output "connectivity-ok" if the received pack is self-contained and
 connected.
 -v
 Run verbosely.
 <repository>
 The URL to the remote repository.
 <refs>...
 The remote heads to update from. This is relative to $GIT_DIR (e.g.
 "HEAD", "refs/heads/master"). When unspecified, update from all
 heads the remote side has.
 If the remote has enabled the options
 uploadpack.allowTipSHA1InWant, uploadpack.allowReachableSHA1InWant,
 or uploadpack.allowAnySHA1InWant, they may alternatively be 40-hex
 sha1s present on the remote.
SEE ALSO
 git-fetch(1)
GIT
 Part of the git(1) suite
Git 2.26.2 04/20/2020 GIT-FETCH-PACK(1)


site with difference loading levels of OMMT were investigated. The back temperature of elastomeric nanocomposite heat shield with different thickness (2.5 and 5 mm) was measured using oxyacetylene flame test and the effect of clay on it was studied. Also, the ablation rates were calculated.The results showed that NBR\OMMT nanocomposite with higher loading level of clay (13.35 wt%) has lower ablation rates (about 7 times in mass loss and about 11 times in erosion rate) and lower magnitude of back temperature (about 513°C) than its composite counterpart. From the viewpoint of thermal shielding capability, elastomeric nanocomposites exhibit better ablation resistance.<\div>
۸The effect of shear strain amplitude and loading cycle on the horizontal characteristics of fiber reinforced nanocomposite elastomeric seismic isolators
اطلاعات انتشار: کنفرانس بین المللی فرآورش پلیمرها، سال
تعداد صفحات: ۴
Fiber–reinforced elastomeric isolators (FREIs) are a new generation of seismic isolation devices which steel plates are replaced by fibers. FREIs have a number of advantages over SREIs including; superior energy dissipation capability, potentially low manufacturing cost, light weight, and the possibility of being produced in long rectangular strips or large sheets and being modified to the required size locally [1]. The main purpose of this work was to investigate the effect of shear strain amplitude and loading cycles on the horizontal characteristics of fiber reinforced nanocomposite elastomeric isolators (FRNEIs) which were manufactured based on nanocomposite rubber compounds. The results of typical isolator horizontal test showed that by increasing the number of cycles of loading and shear strain, the values of effective horizontal stiffness and shear modulus of FRNEI decrease and the viscous damping increases. This stress softening is known as Mullins effect which occurs in the filled rubbers [2].<\div>
۹Toughening Mechanism of Polymer\ Layered Silicate Nanocomposites
اطلاعات انتشار: کنفرانس بین المللی فرآورش پلیمرها، سال
تعداد صفحات: ۴
Phenolic resin (PR) have been widely used as coating, adhesives, composites, etc. due to their excellent flame and chemical resistance, thermal stability and dimensional stability properties However their brittleness has significantly limited their widespread applications.In this work, highly filled clay nanocomposite systems based on asbestos– phenolic system are prepared and investigated by XRD, 3 point bending test, SEM and TOM microscopy.The results showed improvement of fracture toughness of highly filled nanocomposites by adding organoclay in nanocomposite.The toughening mechanism of highly filled nanocomposite is crack branching due to flake shape and strength of clay sheets.<\div>
۱۰Quantitation of the reinforcement effect of SiAlON nanoparticles on the tribological and corrosion resistance of epoxy coating
اطلاعات انتشار: کنفرانس بین المللی فرآورش پلیمرها، سال
تعداد صفحات: ۴
The effect of incorporating SiAlON nanoparticles loading level (0, 3, 5 wt.%) on abrasion resistance, and the corrosion resistance of epoxy–coated steel was investigated by electrochemical impedance spectroscopy (EIS). The electrochemical monitoring of the coated steel over 35 days of immersion in 3.5 wt.% NaCl solutions at room temperature suggested the beneficial role of SiAlON nanoparticles in significantly improving the corrosion resistance of the coated steel. nanocomposites containing 5 and 3 wt% of SiAlON nanoparticles improved wear resistance, 34% and 59%, respectively. Nanoparticles characterized by linier light scattering analysis(LLS). The SiAlON nanopowders size of deagglomerated product is mostly less than 100 nanometers. The epoxy resin chemical resistant coating grade based on bisphenol A was used with polyamine hardener as a curing agent<\div>
۱۱Improvement of Mechanical and Chemical Properties of Epoxy Coating forNatural Gas Pipeline by SiAlON Nanopowders
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۶
The influence of SiAlON nanoparticles loading level (0, 3, 5, 7 wt%) on chemical and mechanical properties of internal nanocomposite coating based on Epoxy resin\ SiAlON were experimentally investigated. The nanocomposite coatings were characterized by fracture toughness, abrasion andimmersion tests, followed by scanning electron microscopy (SEM) of the surface cracks samples. Also nanoparticles characterized by Linier Light Scattering analysis (LLS). The epoxy resin used was a bisphenol A–type epoxide resin with polyamine hardener as a curing agent. Results indicatean enhancement in the epoxy nanocomposite mechanical and chemical properties due to the addition of small fraction of SiAlON nanoparticles. energy per unit area of crack surface ofnanocomposites with 3 wt% and 5 wt% of SiAlON nanopowders improves compared to neat resin.The nanocomposite containing 5 wt % of SiAlON nanoparticles exhibited the maximum GIC values which are 23% higher. Also nanocomposites with 3 and 5wt% of SiAlON nanopowder in Na2CO3 solution have chemical resistance higher than neat epoxy resin based on crack initiation andpropagation. All of samples in H2CO3 solution have chemical resistance because wasn't shown any crack on samples surface. Also nanocomposites containing 5 and 3 wt% of SiAlON nanoparticles improved wear resistance, 34% and 59%, respectively.<\div>
نمایش نتایج ۱ تا ۱۱ از میان ۱۱ نتیجه


Honestly learn about the host service in IIS In WCF [Article 3]
Source: Internet
Author: User
Tags hosting msmq visual studio 2010
Honestly learn WCF
Article 3 boarding services in IIS

Through the first two articles, we learned how to build the simplest WCF communication model, this includes defining and implementing service agreements, configuring services, hosting services, and configuring clients and accessing services by adding service references. We have a basic understanding of the programming lifecycle of WCF.

The examples demonstrated in the previous two articles must be carried by hand, including the source program and configuration file, with a line of handwriting. In this way, we can have a profound understanding. The knowledge of WCF is scattered and complex, so you must study and practice it in a down-to-earth manner. If you haven't done it, go back and try again.

Today, let's take a deeper look at some new boarding knowledge: Boarding services in IIS.

In the first two examples, we have created a console application to host the service. This boarding method is called "Self-hosting", that is, the WCF Service and the application are integrated. This boarding method has some advantages. It requires the least framework support (only one console application is required, and can be created and run everywhere). Therefore, configuration and use are the simplest, in addition, the console program can monitor errors that occur during the running of the WCF Service. In the development service stage, this method can facilitate debugging.

However, as a final product deployment, the self-hosted host mode is not suitable, and the applications are unstable compared with the frameworks (such as IIS and Windows Services, the lifecycle is shared between the WCF and the application. After the application is closed, the WCF also stops. Many other features such as process recycling and idle shutdown are not supported. Therefore, to make our WCF meet product-level requirements, we should select a more stable and scalable host for it.

In addition to self-hosting, WCF can also host on IIS, Windows Services, and Windows Process activation services (was. It is popular to host on IIS and Windows Process activation services.

To host in IIS, iis5.1 or a later version is required. IIS manages servicehost for US (remember him, check the Code in article 1 ), it also provides features such as process recycling, idle shutdown, and process running status monitoring, we only need to put service-related files into IIS hosting according to certain organization methods (just like creating a website application or virtual directory), IIS will manage everything for us. This kind of hosting is supported by many systems, from Windows XP SP2 to Windows Server 2008, so it is very popular. However, it also has its disadvantages. It can only accept HTTP binding, but does not support TCP, MPs queue, and MSMQ.

Since iis7, the so-called Windows Process activation Service (was) function is provided. If you store WCF in was, all binding protocols (such as TCP) can be supported ), protocols such as MSMQ, in the intranet and. NET programming model has a great performance advantage, so was should become the main way of WCF boarding in the future, but iis7 requires Windows Vista and later versions to be supported, it may take a few days for him to become popular.

We will first learn how to host in IIS. Remember that iis host only supports HTTP binding.

The following describes the experiment environment:
Windows 7 family advanced Edition SP1
Iis7
Visual Studio 2010 ultimate SP1

Honestly, we did not use ide to help build a project today. We wrote a Service hosted on IIS by hand.

1. Create a physical location for the IIS application
The IIS application needs to map to a physical path of the local drive. We should first build it.
I created this folder under c: \ WCF \ and named it iisservice. (Hellowcf was created in the first two articles. Do you remember)

2. Create an IIS application
The physical path has been created. Now we create an application on this location. Click Start> control panel, find the management tool in the project, and then open IIS.

Expand the node on the left, right-click the default website node, and select "add application"

Specify an alias for the application. This can be set as needed. This name will be part of the future service address. I will start it as iisservice and select the folder we just created as the physical path.

Click OK. the IIS application is created. We can see that this application is added to the default website, but there is nothing in it.

3. Create a service file
We need to create several files according to the requirements of the IIS host and put them in IIS to host our services. Of course, the service information is also described in these files.
(1) SVC file.
SVC is the meaning of service. We need to create a XXX first. put the SVC file in the IIS application directory. This file is the service entry. The client needs the file address to access the service (including the original data exchange, of course ).
Create the file manually, open vs2010, and choose file menu> New> file. In the regular section, select a text file and click "open.

This should be a SVC file, but not a. txt file. Therefore, save it as another file. When saving it as another file, select the storage type as all files. I name this file hellowcfservice. SVC, which can be used as part of the service address. The storage location is the location where we just created the IIS application.

Now let's edit the content of this file. It's very simple. There is only one line of code.
[HTML]View plaincopy
 1. <% @ Servicehost Language = C # DEBUG = "true" service = "learnwcf. hellowcfservice" %>
If it is framed by <%>, it indicates that it is contained on a server, and the @ servicehost tag indicates that it is a WCF Service. Think of the servicehost object in the previous two codes. Language = C # indicates that we use the C # language to write code. DEBUG = true, as the name suggests, indicates the service attribute. It indicates the implementation class of the service, you must use a fully qualified name to include a namespace. I started a namespace named learnwcf. We put the service definitions under this namespace, And the hellowcfservice is the service implementation class. We will improve the content of this class.
We can see that .. The SVC file is equivalent to a wizard, which helps us find the service location in the IIS host. The specific code can be written in another place (in fact, it can also be written in the SVC file, which is not recommended ).

Save the written content and proceed.
Next, we will write the class file that defines the service. But before that, we should first create a storage location for the class files. the IIS code files should be stored in the app_code subdirectory of the IIS application directory, so we should first create this folder.
We can see that the hellowcfservice. SVC we just created has been recognized as a WCF Service.

(2) CS files
Return to vs2010, choose File> New> file, and select a text file.
This time we will create a class file named hellowcfservice. cs. Note that we should select the storage type as all files when saving the file, and select the created app_code folder as the path.
To write this file, we should be familiar with defining and implementing the service agreement here. Let's try to write it down on your back.
[CSHARP]View plaincopy
 1. Using system;
 2. Using system. servicemodel;
 3. Namespace learnwcf
 4. {
 5. [Servicecontract]
 6. Public interface ihellowcf
 7. {
 8. [Operationcontract]
 9. String hellowcf ();
 10. }
 11. Public class hellowcfservice: ihellowcf
 12. {
 13. Public String hellowcf ()
 14. {
 15. Return "Hello WCF! ";
 16. }
 17. }
 18. }
This code should be very skillful. If you have any questions about this code, go back to the first article and review it.

Save it. Let's proceed.

(3) web. config file
We know that we also need a configuration file to configure the endpoint, service, behavior, and so on. This configuration file is roughly the same as what we have previously created.
Return to vs2010, or create a text file and save it as Web. config. This file name cannot be changed. The save path is under the iisservice directory of the IIS application we created (stored together with SVC)
Write it down first and explain it again:
[HTML]View plaincopy
 1. <Configuration>
 2. <System. servicemodel>
 3. <Services>
 4. <Service name = "learnwcf. hellowcfservice" behaviorcon


Take the 2-minute tour ×
I'm reading Terry Gannon's Moonshine Beyond the Monster, and in section 2.4.3 he hints at (but does not explicitly describe) a way to extend the action of $SL_2(\mathbb{Z})$ on modular forms to an action of the braid group $B_3$. Here is what he says about this action:
First, we lift modular forms $f : \mathbb{H} \to \mathbb{C}$ to functions $\phi_f : SL_2(\mathbb{R}) \to \mathbb{C}$ as follows: let
$$\phi_f \left( \left[ \begin{array}{cc} a & b \\\ c & d \end{array} \right] \right) = f \left( \frac{ai + b}{ci + d} \right) (ci + d)^{-k}.$$
Thinking of $f$ as a function on $SL_2(\mathbb{R})$ invariant under $SO_2(\mathbb{R})$, we have now exchanged invariance under $SO_2(\mathbb{R})$ for invariance under $SL_2(\mathbb{Z})$. ($SO_2(\mathbb{R})$ now acts by the character corresponding to $k$.) In moduli space terms, an element $g \in SL_2(\mathbb{R})$ can be identified with the elliptic curve $\mathbb{C}/\Lambda$ where $\Lambda$ has basis the first and second columns (say) of $g$, and $\phi_f$ is a function on this space invariant under change of basis but covariant under rotation.
Second, $SL_2(\mathbb{R})$ admits a universal cover $\widetilde{SL_2(\mathbb{R})}$ in which the universal central extension $B_3$ of $SL_2(\mathbb{Z})$ sits as a discrete subgroup. Unfortunately, Gannon doesn't give an explicit description of this universal cover (presumably because it's somewhat complicated).
Question: What is a good explicit description of this universal cover and of how $B_3$ sits in it (hence of how it acts on modular forms)? In particular, does it have a moduli-theoretic interpretation related to the description of $B_3$ as the fundamental group of the space $C_3$ of unordered triplets of distinct points in $\mathbb{C}$? (These triplets $(a, b, c$) can, of course, be identified with elliptic curves $y^2 = 4(x - a)(x - b)(x - c)$.)
share|improve this question
4 Answers 4
up vote 8 down vote accepted
You can think of the space of positively oriented covolume-one bases of $\mathbb{R}^2$ as a torsor under $SL_2(\mathbb{R})$, i.e., it is a manifold with a simply transitive action of the group. If you choose a preferred basepoint, such as $(\mathbf{i},\mathbf{j})$, you get an identification with the group. You can think of elements of the universal cover as positively oriented area-one bases equipped with a homotopy class of paths in $\mathbb{R}^2 - \{0\}$ from $\mathbf{i}$ to the first element of the basis. There is a reasonably straightforward composition law that involves multiplying matrices and composing paths.
Gannon's description of lifting to $SL_2(\mathbb{R})$ implies the lifts of even weight modular forms to $\widetilde{SL_2(\mathbb{R})}$ are invariant under the action of $B_3$. In particular, classical modular forms are rather boring from the perspective of the braid group. In order to detect the central extension, you need to consider modular forms of fractional weight. When the weight is not an integer, you don't get an action of $SO(2)$, but instead, an action of the universal cover $\mathbb{R}$. The resulting action of $B_3$ is necessarily nontrivial, since the restriction to the center is by a nontrivial character of $\mathbb{Z}$. I don't know many explicit constructions of fractional weight forms, other than half-integer weight forms like $\eta$ and theta functions, and vector-valued forms constructed from them. However, you can generate a family of examples by choosing powers of the cusp form $\Delta$, which admits a logarithm since it is globally regular and nonvanishing.
My understanding of the explicit relationship to configurations of points and elliptic curves is the following: Given a path of triples of distinct points $(a_1(t),a_2(t),a_3(t))$, we get a path on the space of elliptic curves of the form $y^2 = (x-a_1(t))(x-a_2(t))(x-a_3(t))$, but this will throw away an action of real translations and dilations (irrelevant) together with the central extension and the circle action (important). If we just look at the isomorphism types (i.e., the $j$-invariants) of the curves, we get a path through the quotient of the upper half plane by $SL_2(\mathbb{Z})$. We need to choose a discrete structure to remove the quotient by the center, and a one dimensional continuous structure to promote our space to three dimensions. To retain the angular information that we lost by passing to elliptic curve isomorphism, we fix a tangent direction at infinity to remove rotational symmetry. This tangent direction is manifested when we choose our discrete structure: a homotopy class of nonintersecting paths from the three points to infinity, because we demand that the paths asymptotically approach infinity in that direction. The elliptic curve is a double cover of the complex projective line, ramified at the three points and infinity. We can choose once and for all a uniform convention for lifting the three paths to primitive homology cycles, such that any pair generates $H_1$, and one cycle is the sum of the other two, so those two form a preferred basis. To get the parametrization of $\widetilde{SL_2(\mathbb{R})}$ from the first paragraph, we choose a preferred basepoint configuration of three points with paths from infinity and asymptotic direction, and consider a triple $(a_1(t),a_2(t),a_3(t))$ that starts at the basepoint. By uniqueness of homotopy lifting, we get a family of tangent vectors at infinity together with a family of elliptic curves with oriented bases of homology. By rescaling the bases in $\mathbb{R}^2$ to have unit covolume, we get the parametrization in the first paragraph.
share|improve this answer
There is a straightforward way to pass between the description of $\widetilde{SL_2(\mathbb{R})}$ in my first paragraph and Robin Chapman's description, but Robin's description is not only more concise, but lends itself to nice descriptions of finite-order covers like the metaplectic group (using branches of $n$th roots of $cz+d$). – S. Carnahan Apr 4 '10 at 19:49
$\widetilde{\textit{SL}_2(\mathbb{R})}$ is not so complicated, but one of the best descriptions is just that. It has no faithful finite-dimensional representations, which makes things a little tricky. It's easy to see that $\textit{SL}_2(\mathbb{R})$ is topologically a solid torus, so it does have a central extension by $\mathbb{Z}$.
Another description of this central extension is to think of $PSL_2(\mathbb{R})$ acting on the hyperbolic plane. Then $\widetilde{SL_2(\mathbb{R})}$ is pairs $(g,\phi)$ where $g \in PSL_2(\mathbb{R})$ and $\phi:\mathbb{R}\to\mathbb{R}$ is a map that induces the map from $S^1$ to $S^1$ induced by $g$ on the circle at infinity. (Note that this goes by a quotient from $SL_2(\mathbb{R})$ and then centrally extends back again.)
For the relation to $B_3$, you can think of $PSL_2(\mathbb{Z})$ as the mapping class group of the 4-times punctured sphere, with one puncture (at infinity) distinguished and required to go to itself. To go from there to its central extension $B_3$, you remove a disk (rather than a point) around infinity, and only look at isotopies that fix that boundary, which is similar to what happened at the circle at infinity above.
More generally, all mapping class groups have a unique central extension; if there's a distinguished point, you can do it in the braid-like way (looking at isotopies that fix a boundary circle), while if there isn't, you do it by lifting the map of the surface to a map from $\mathbb{H}^2$ to itself (not an isometry) and then lifting the action on the circle at infinity to a map from $\mathbb{R}$ to


text:
Politics, Language, and Thought
The Somali Experience
Twelve years after independence, a military government was able to settle the acrimonious controversy by announcing that Somali would be the official language and Latin the basic script. It was hoped that this choice would foster political equality and strengthen the national culture. Politics, Language, and Thought is an exploration of how language and politics interrelate in the Somali Republic. Using both historical and experimental evidence, David D. Laitin demonstrates that the choice of an official language may significantly affect the course of a country's political development.
Part I of Laitin's study is an attempt to explain why the parliamentary government was incapable of reaching agreement on a national script and to assess the social and political consequences of the years of nondecision. Laitin shows how the imposition of nonindigenous languages produced inequalities which eroded the country's natural social basis of democracy.
Part 2 attempts to relate language to political thought and political culture. Analyzing interviews and role-playing sessions among Somali bilingual students, Laitin demonstrates that the impact of certain political concepts is quite different when expressed in different languages. He concludes that the implications of choosing a language are far more complex than previously thought, because to change the language of a people is to change the ways they think and act politically.
A Note on Transliteration
Part 1 Somalia - The Politics of Language
1. Introduction: Political Issues of Language Choice
2. The Somali Language and the Somali People
3. Foreign Influence in Somalia
4. Language Politics in Somalia: The Politics of Nondecision
5. Decision and Political Consequences
Part 2 - Somali - The Language of Politics
6. Linguistic Relativity: A Theoretical Introduction
7. Linguistic Relativity: An Empirical Formulation
8. Linguistic Relativity: The Somali Experience

source: HuggingFaceFW/fineweb-edu


text:
Using open source tools to stress test video streaming at scale
In this post, I want to share something that we have been working on with BlazeMeter for several years. In this project, we had the opportunity to contribute to the open source code of JMeter, making this load testing tool capable of simulating load in video transmission protocols and thus, be able to execute performance tests.
As we have also been able to use this tool in some of our projects, we have some tips that will help you prepare and execute performance tests on HLS (the protocol that we're working on).
I want to especially thank Roger Abelenda, Luis Martínez and Sebastián Lorenzo from Abstracta for their contribution to this article. I hope this post can be useful, and serve as a guide for this practice.
Any type of system that will be used by multiple users, but in particular video streaming, needs to be tested to minimize any risk before launch. In the rest of the post, I will focus specifically on these tests.
If you want to know more about when you should start performance testing, at what levels, with what load, etc, you can check out some of our other articles:
- Why Performance Testing is Necessary
- When is the Best Time to Start Performance Testing?
- How to Make a Performance Test Plan
Before beginning, remember that as in any performance test, we need to simulate the interaction between the client and the server, so in this case, we'll concentrate on the HLS (HTTP Live Streaming) protocol.
How does the HLS protocol work?
You can find Apple's explanation of the HLS protocol in this article. Basically, the protocol has certain steps to follow, which I'll explain below. Although the protocol is designed for three variants, On Demand, Live, and Event, I'll focus on the "On Demand" example. Once you have understood one, it's very easy to understand the others.
From the Server Side (Encoder)
The audio or video that will be transmitted can be played at different levels of quality, bitrates and resolutions. Each version is called a "variant." So, on the server side we have different variants of the same video, with different resolutions. In the example seen in the image above, we have the same video in three variants, one in low resolution designed for a 3G connection (this is just an example to help understand the protocol better), another with better resolution for when the viewer is connected to WiFi, and a third variant with the highest resolution for when someone watches the video on an AppleTV (since this protocol was created by Apple, we will put this as the example).
The different variants are divided into small segments by the encoder (Media Segment Files). In other words, each video is going to be split into many pieces and saved in a ".ts" extension file.
The encoder creates a Media Playlist for each variant with the URLs of each segment. This would be like the index of the segment files, so that it's possible for the client to know how to assemble the video from all those segments.
The encoder also creates a Master Playlist File with the URLs of each Media Playlist. This way, the client will know which variants are available (the available resolutions to download).
From the Client Side (Video or Audio Player)
The Master Playlist is downloaded, and with it come the different Media Playlists with the variants (different video qualities, bitrates and resolutions), which contain the references to the segments and the corresponding videos.
The segments indicated by the Media Playlist are downloaded in real time and in the case of live video or event, the Media Playlist is downloaded periodically to check if there are new segments that have been added.
Here's the Step-by-Step Protocol
Below, you'll see how a message flow would be like, when playing a video from a browser. This is a simple example so you can see the step by step clearly and finally understand it.
That is the Master Playlist. If you access that URL, an m3u8 extension file will be downloaded, whose content is as follows:
These are basically the descriptions of the variants. The player can automatically choose or give the user the possibility to indicate what type of variant he or she wants to download (a video in high resolution or one of low quality, which would be convenient if he or she has a bad internet connection). Imagine then that user chooses to download the lower quality option, which would be the last one (480 by 270 resolution). If you look at the Master Playlist file, the URL to the corresponding Media Playlist would be the following: _URL_ and the content (trimmed) would be as follows:
This contains the list of segments of a 13-second video. The client is the one who will ask for these segments one by one and will know what to do with them.
To see it, go to the "About Us" section of the Blazedemo site, then go to the Chrome developer tools (F12 key), and on the Network tab, filter with the following regular expression:
This way, you'll only see the requests to Master Playlists, Media Playlists (those ending in m3u8) and the segments (ts extensions).
How does the JMeter Plugin work?
The plugin is very simple, there is only one request to the Master Playlist and then all the rest is automatic, just as a video player would be. It's not necessary to do all the requests separately or to parse the answers to see what requests should be made next. The protocol logic is encapsulated in a single JMeter Sampler.
After installing the plugin, you just have to define the URL of the Master Playlist and then indicate some parameters to see which video you want to simulate its reproduction (the one that has the maximum quality, the minimum, a specific one, for how long, etc.).
When running a test with this plugin, this is what the result would look like in JMeter:
You can see that the first request is to the Master Playlist, the second to the Media Playlist (this depends on what we have configured in the sampler) and then the sequence of segments begins.
This is what the result would look like in BlazeMeter:
Now that we covered how the HLS protocol and plugin work, here are some considerations to keep in mind when putting together and running our tests:
To Keep in Mind When Defining the Script
You have to know what test you want to run and for that, it's important to think about the variables: how many concurrent users there will be, if there is a ramp-up, and if so, for how long, what flows over the system, different accesses, data that could vary, etc. It's also important to know what type of video you want to download, that is, an event, live or VOD (video on demand). In any case, you have the possibility to indicate the duration of the video you want to download, which will basically determine the duration of the test.
To assemble the script, you can follow a step-by-step sequence similar to the one I explained earlier in the Blazedemo example, although you can also use the Chrome extension to record scripts in JMeter and Taurus. Starting 11 minutes into this video, you can see how to use this extension.
As always, it's essential to add assertions to these tests because it's not enough to check if the HTTP response code is correct (something that JMeter does automatically). It's better to add some validations to the answers to make sure you are getting what you expect. As there isn't much to do with the segments, since the content is binary, the content options that you can validate are only the content of the Master Playlist and Media Playlist.
Another thing that is extremely useful is using the HLS sampler within a transaction controller which allows you to obtain the response time of the entire execution and thus be able to compare the duration of the actual download and the video time that is requested to download.
Things to Remember When Defining the Scenario
- If it's possible to access the video from different locations around the world, do the tests from different locations as well (Blazemeter allows you to easily configure the distribution of the tests from different places around the world).
- Try different scenarios, different user loads, peaks, and stress.
- Define if you want to simulate with or without HTTPS.
- Are there load balancers? Are CDNs used? Our suggestion is to test with "nothing in the middle" and also test the entire infrastructure as it would be received by the user. For this, you probably need to leave the URL as a parameter in your script so that it's possible to configure from the execution in BlazeMeter which environment you want to stress.
It's always important to calibrate the test. That is, to run several tests to determine how many VU (virtual users) it's possible to run from a single BlazeMeter engine, or from a single machine if you run the test locally. Typically JMeter can execute more than 500 threads from the same machine, but this depends a lot on the script, and of course, on the characteristics of the machine, so it's best to test it. It's also important to keep an eye on the health of the machines from where you run the test, since if they were to become saturated, the results wouldn't be reliable.
Important Aspects to Consider When Viewing and Analyzing the Results
- If you set

source: m-a-p/FineFineWeb


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Effects of the Mono Winds
August 30, 2012
Tioga Road near Mono Pass Trailhead
Dramatic evidence of the regional phenomenon known as the Mono Winds can be seen just off the Tioga road near the Mono Pass Trailhead. Numerous trees are down in this area, having been blown down last winter. When a high pressure system is over the Great Basin, the clockwise movement of air pushes up and over the Sierra and picks up speed as it rushes down the western slopes. The rugged topography funnels some of that air, further increasing the speed and intensifying localized effects. The Mono Winds can easily reach 50 mph and in extreme cases exceed 100 mph. It is likely that the wind that knocked these trees down was funneled by the Tioga pass and continued down the Tioga road. Most of the downed trees are near the road and lying parallel with the road. The weather patterns that cause the Mono Winds occur from October to April but are most common in December and January.


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New York, NY – Among moms with a child between the ages of two and six, reading is the activity they tend to spend the most time doing with their child each day, according to a survey of over 1,000 moms conducted by Ipsos Public Affairs on behalf of General Mills. Over half of moms (53%) select reading as one of the two activities they spend the most time doing with their child, followed by watching TV or movies (35%), playing with toys or dolls (29%), riding in the car to get to various activities (19%), and playing sports or outdoor activities (18%).
- Mothers 30 and older are more likely than younger moms to select reading as one of the two activities that they spend the most time doing with their child (57% vs. 44%).
- Mother with a household income of at least $50,000 are also more likely than those who are less affluent to select reading (59% vs. 44%).
Additionally, eight in ten moms (81%) report that they started reading to their child before their first birthday. An additional 12% started doing so when their child was one. Few (6%) waited until the child was older, and all started reading with their child before their child turned five.
- Hispanic mothers are less likely to begin reading to their child before they turn one (68%).
- Moms who are married are more likely than moms who are unmarried to begin reading to their child at this early age (84% vs. 73%).
Two thirds of moms (67%) read to their child at least daily, including 15% who do so several times per day. Another quarter (26%) say that they read with their child a few times per week, 5% do so about once a week, and just 2% do so less than once a week. Less than 1% of mothers surveyed reported that they never read to their child.
- Older moms are more likely than those who are younger to read to their child at least once a day, if not more: moms aged 40 and older: 76%; aged 30-39: 68%; aged 18-29: 57%.
- Moms who have graduated from college (73%), those have a household income of $50,000 or more (73%), those who are married (73%), and those who are Caucasian (70%) are among those more likely to report that they read to their child at least daily.
- Moms who started reading to their child before their first birthday are more likely to read with the child on a daily basis than are those who waited until their child was older (71% vs. 47%).
Mothers utilize a variety of methods to encourage their children to read. Three quarters select books that they think would really interest their child (76%) or always have books on hand (76%). Majorities also say that they make reading part of their child's daily routine (69%), let their child see them reading (59%) and talk about books with their child (51%). More than two in five (44%) say that they go to the library together, though just one in ten (9%) use incentives or rewards to encourage their child to read.
- Moms 40 and older tend to use more of these strategies than do younger moms. For example, 89% of moms aged 40 and up say that they always have books on hand compared to 65% of moms under 30. These older moms are also much more likely to go to the library with their child (53% vs. 32%).
Bedtime is typically when moms read to their child, selected by 61%. Over half (56%) say that they tend to read to their child in the evening, though fewer do so in the afternoon (31%) or in the morning (12%).
While all mothers say that they read to their child, how long they spend doing so varies quite a bit. Just 27% say that they spend 10 minutes or less when reading to their child, over half (54%) spend between 11 and 20 minutes reading with their child. One in five (19%) spend over 20 minutes when they sit down to read with their child. The average reading time is 16 minutes.
- Younger moms tend to spend less time when they read with their child than do older moms. Over a third of moms under 30 (35%) say that they typically spend 10 minutes or less while just 18% of moms 40 and older say the same.
- Those who are reading to their child less frequently also tend to spend less time when they do so. Moms who read to their child less than once a day are twice as likely as moms who read to their child on a daily basis to say that they spend 10 minutes or less (39% vs. 21%).
Though most moms make time each day to read to their child, busy schedules (61%) and cooking and household chores (57%) are the most common reasons that prevent them from spending more time reading. Many also say that their work or career (44%), spending time with their other children (33%) and the child's attention span impedes them from spending more time reading with their child. Few blame their local library's limited hours (3%) or not having a library close by (2%).
- Seven in ten moms who are employed full-time (70%) say that their job prevents them from spending more time reading with their child. Hispanic (54%) and African American (60%) moms are more likely than those who are white (41%) to say that their job is an obstacle when it comes to spending more time reading with their child.
Children tend to have a wide selection of books at home, with moms reporting that their child owns 55 books on average. More then nine in ten (92%) have over 10 books at home, including 42% who have over 50.
- Moms 40 and older (58%), college graduates (49%), those with a household income of $50,000 or more (49%), and Caucasians (50%) are most likely to say that their child owns over 50 books. In contrast, moms under 30 (26%), those who are unmarried (29%), Hispanic moms (27%) and African American moms (21%) are least likely to say so.
When selecting books for their child, moms are most likely to say that the educational value is one of the most important factors (62%). Roughly four in ten also consider colorful illustrations (43%), the topic (40%), the lessons or morals (38%) and the length and complexity (38%) as a top factor when choosing books for their child. They are less likely to consider their own personal experience (31%), recommendations from others (10%), or the author (3%) to be important when selecting children's books.
- The criteria moms use to select books vary with the age of their child. Those with a child ages two to four are more likely than those with a child ages five or six to say that the educational value such as letters, numbers, etc. (65% vs. 55%) and colorful illustrations (49% vs. 36%) are top factors when choosing a book. Conversely, those with older children are more likely to consider the topic (44% vs. 38% of moms of younger children) and the length and complexity (43% vs. 33%).
Though moms tend to have a multitude of books for their child at home, they also believe that school and public libraries ensure that that all children have access to quality books; nine in ten (90%) agree with this, including 51% who strongly agree.
- At least eight in ten moms across demographic groups agree that all children have access to books thanks to school and public libraries.
However, many (63%) also recognize that when it comes to children's access to books, there is a drastic disparity between middle and lower income neighborhoods in the U.S. At the same time, 37% do not agree.
- Moms who are married (66%), have a college degree (67%), and reside in the Northeast (72%) are most likely to agree with this statement.
These are some of the findings of an Ipsos poll conducted September 28-October 4, 2010. For the survey, a national sample of 1,012 mothers of a child ages 2-6 were interviewed online. Weighting was employed to balance demographics and ensure that the sample's composition reflects that of the universe. A survey with an unweighted probability sample of this size and a 100% response rate would have an estimated margin of error of +/- 3.1 percentage points 19 times out of 20 of what the results would have been had the entire population of mothers with a child ages 2-6 in the United States had been polled. All sample surveys and polls may be subject to other sources of error, including, but not limited to coverage error, and measurement error.
For more information on this press release, please contact:
Senior Vice President
Ipsos Public Affairs
Senior Research Manager
Ipsos Public Affairs
Ipsos is a leading global survey-based market research company, owned and managed by research professionals. Ipsos helps interpret, simulate, and anticipate the needs and responses of consumers, customers, and citizens around the world.
Member companies assess market potential and interpret market trends. They develop and build brands. They help clients build long-term relationships with their customers. They test advertising and study audience responses to various media. They measure public opinion around the globe.
Ipsos member companies offer expertise in advertising, customer loyalty, marketing, media, and public affairs research, as well as forecasting, modeling, and consulting.

source: openbmb/Ultra-FineWeb


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Top 10 Swing Wing Aircraft
Here is the list of Top 10 Swing Wing Aircraft, The swing-wing was the design of choice for strategic bombing and attack aircraft in the 1960s and 1970s, when the future of advanced high-speed flight incorporated the swing-wing capability to streamline aircraft further. A swing-wing is an airplane wing or set of wings that can be swept back and then returned to its original straight position during flight, allowing the aircraft shape to be modified in flight.
List of Top 10 Swing Wing Aircraft
1. Bell X-5 ( Swing Wing Aircraft )
The Bell x5 was an experimental single-seat single-engine jet-powered fighter design prototype that was the first to use in-flight variable-geometry wings. Its roots were in the German Messerschmitt mep.1101, which the x5 heavily borrowed from in terms of the overall design. Only two x5 prototypes were built.
The x5 program was being considered for an American nato low-cost tactical fighter initiative when the two aircraft made their initial flights on June 20 and December 10, 1951, respectively.
Nearly 200 flights were completed at speeds up to Mach 0.9 and altitudes of up to 40 000 feet. On the 14th of October 1953, one aircraft was lost after it failed to recover from a 60-degree sweepback air force spin. Captain Ray Popson died in the crash at Edwards Air Force Base, although the other x5 stayed at Edwards and was used as a chase plane until 1958.
2. General Dynamics F-111 Aardvark ( Swing Wing Aircraft )
The Aardvark was the first variable-sweep aircraft to reach production, with wings that could sweep from 16 to 72.5 degrees. However, a swing-wing wasn't the only innovative feature on this plane.
It also pioneered the way for terrain-following radar, allowing it to fly at fast speeds at low altitudes. The f-111 aardvark swing-wing bomber was debuted in 1967 and decommissioned from active service with the US Air Force in 1996, followed by the ef-111 raven in 1997.
3. Mikoyan-Gurevich MiG-23 ( Swing Wing Aircraft )
The Mig-23 flogger was the first Soviet aircraft to have variable-sweep wings, paving the way for the equally successful Mig-27 flogger ground strike variant. It was also the first Soviet jet to have looked down or shot down radar, as well as the first to have side-mounted air intakes. The MiG-23 was first commissioned into the Soviet air forces on January 4, 1974, and was withdrawn in 1998.
The tornado is one of the most iconic swing-wing aircraft. It also contains thrust reversers, which are a unique feature of fighter aircraft. The reversers were installed in order to improve s-tall capability. The Tornado is also a twin-engine variable-sweep wing multi-role combat aircraft developed and constructed jointly by Italy and the United States.
West Germany and the United Kingdom The Pana via tornado was designed and produced by Pana via aircraft Gmbh, a tri-national venture comprised of British aerospace MBB of West Germany and Alitalia of Italy. It made its first flight on August 14, 1974, and entered service in _PHONE_.
5. Sukhoi Su-24 ( Swing Wing Aircraft )
The Sukhoi Su-24 fencer was the Soviet response to the f-111 aardvark of General Dynamics. After 35 years of active service, the Soviet design was no doubt inspired by the spectacular and powerful swing-wing American design and strove to match it with an equally effective mount worthy of her soviet airmen.
Sukhoi OKB has produced around 1400 su-24s in three different operational variants and delivered them to a handful of foreign operators, signaling the end of the outstanding achievement in many aspects of her makeup.
6. Rockwell B-1B Lancer ( Swing Wing Aircraft )
It's the US Air Force's only active swing-wing aircraft, and it packs a punch. This Mach 1.25 bomber can carry 125 000 pounds of payload and has over 120 000 pounds of thrust, allowing it to get somewhere swiftly.
Using unguided gp munitions, the B1 was first employed in combat in support of operations in Iraq during Operation Desert Fox in December 1998. B1s were later employed in Operation Allied Force Kosovo and, more recently, Operation Enduring Freedom in Afghanistan and the 2003 Iraq invasion.
7. Tupolev Tu-160 ( Swing Wing Aircraft )
The Tupolev Tu-160 has been the largest jet-powered swing-wing combat aircraft platform ever constructed, mounting the most powerful jet engines installed to any military aircraft since its creation. It was designed as a direct counter product to the US Air Force's Rockwell.
The tu-160 was planned to perform a slightly different duty of standoff missile launching, whereas the b-1 was designed to deliver vast quantities of precision weapons in the form of cruise missiles and other potent air-to-surface kinds. The TU-160 started operational duty with the 184th guard's heavy bomber unit at Priluki air station in the Ukrainian SSR in April 1987.
8. Tu-22M ( Swing Wing Aircraft )
The Tupolev tu-22m backfire is a supersonic swing-wing modification of the original Tupolev tu-22 blinder medium bomber from the 1960s. It is a dedicated strategic bombing and naval strike platform that predominantly served Soviet objectives during the Cold War and continues to do so now.
The tu-22m is a development of the original TU-22 blinder, which failed to impress on many fronts. However, the tu-22m featured enough important upgrades that it could be considered an entirely new bomber aircraft, with enhanced missile armament, supersonic flight, and variable-geometry wings.
9. Su-17 ( Swing Wing Aircraft )
The Sukhoi Su-17 Fitter, a Mach 2 capable fighter bomber, was a development of the successful Sukhoi Su-7 fitter, a fighter bomber family line detailed elsewhere on this site. The aircraft incorporated a partial variable geometry wing swing wing system and improved upon the former's takeoff and landing attributes as well as low-level performance required during ground attack runs.
The su-17 was developed into the export su-20 and su-22 fitter models with varying avionics engines and weapons. In total, 2867 su-17 su-20su-22 fitters were produced, with nearly half of these going to soviet export customers. Over a dozen countries also took delivery of the type, making it a staple fighter bomber throughout the cold war.
10. Grumman F-14 Tomcat ( Swing Wing Aircraft )
It's grown into one of the most stunning navy planes ever flown. The f-14 could reach Mach 2.34, had over 54 000 pounds of thrust, and starred in the best aviation movie ever produced. Unlike the f-111b, which was born from a land-based fighter bomber airframe, the f-14 was built from the start as a carrier-based fighter. The f-14, on the other hand, retains many of the f-111b's attributes and components.
Swing-wing variable geometry wing assemblies radar system with long-range missile support two-man crew and twin-engine layout total f-14 production by Grumman yielded 712 aircraft, which were manufactured from 1969 to 1991 non-combat attrition proved relatively high for the series, with some 160 lost in accidents alone many preserved f-14 tomcats are showcased at outdoor and indoor displays across the United States today


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Multi-family and student housing are two residential building types particularly well suited to maximizing mass timber's attributes, a synergy that will help deliver needed housing in a faster and more cost-effective manner and with smaller construction crews. Mass timber, an alternative structural system and framing material to concrete and steel, is relatively new to California and much of the United States, but Europe and Canada have been building with it for decades. Mass timber is made up of massive wood panels, posts, and beams that are comprised of layers of fast-growing soft woods stacked with perpendicular grain directions and glued under pressure or nailed to create members as strong as, and in some cases more resilient than, steel or concrete.
While there are a handful of buildings that have used mass timber in California, the state's building codes, up until now, heavily restricted the height and size of buildings that could use it. The recent building code updates, which went into enforcement effect on July 1, adopted parts of the International Building Code and expanded the codified acceptable use of mass timber–making the building material available to mid and high-rise multi-family and student housing projects, among others.
The housing crisis continues to rage across California cities. Despite government efforts to streamline approvals, overrule local housing development restrictions, and increase public funding developers can't build enough housing fast enough to meet the persistent demand. Multi-family housing, especially in dense urban settings, is particularly applicable to mass timber structural frames in that the dimensional modules for the dwelling units align with ideal structural grid spacing and material widths within a mass timber system. Urban sites also tend to have very little lay-down space or site storage for materials, so the appeal of mass timber is that it can be trucked to site and installed off the truck easily when space is tight. Most mass timber structures rely on a system of wood posts (or columns) and panels (or slabs). When examining ideal square footages and layouts for dwelling units, it is often the case that a 12'-0" structural grid aligns with the typical partition and demising of wall locations, allowing the columns to remain clear of the open space within the units. When interior columns are needed, they can fall in an unobtrusive location in the units and can be exposed as an intentional architectural feature.


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The Society was formed in February 2011 in response to local interest in the archaeology, history and heritage of the Till Valley. Its formation was greatly stimulated by the participation of local volunteers in the archaeological excavations taking place on and around the site of the Battle of Flodden.
The enthusiasm and hard work of the volunteers was recognised by the professional archaeologists leading the excavations. Dr. Chris Burgess, Northumberland County Archaeologist, encouraged and persuaded a 'core' of volunteers that there was a need for a local Society to be involved in local archaeology and history which would complement the activities of other volunteer groups already in place further south in Northumberland.
The idea took hold quickly and indoor meetings and outdoor events were arranged, the first of these being centred on Crookham Village Hall. Crookham is still the 'home' venue although other locations are used from time to time such as Etal Village Hall, Branxton Village Hall and Coldstream Community Centre. Many more local people were encouraged to join the Society and to take part in excavations and field walking.
The establishment of the Society also enabled insurance cover to be put in place so that members might be protected against any risk incurred on its activities including archaeological excavations. The Society itself is covered against public liability. All non-members taking part in an excavation are required to be insured through the Society and twelve months cover is provided by collection of a small charge when they are on site.
There has been a strong growth in membership since 2011 reaching 123 members by March 2017 (including our first overseas member), reflecting the extent of local (and even wider) interest.
Wednesday 2nd June at 7.30 pm Webinar via Zoom Greg Finch will speak on the Dukesfield Smelters and Carriers Project, discovering the heritage of the Dukesfield Arches and lead carriers' routes between Blaydon and the lead mines of Allendale and Weardale in the North Pennine
Border Archaeological Society
Monday 7th June at 7.30 pm via Zoom Dr. Rob Collins: "The Genesis of Northumbria".
North Northumberland Genealogy Group
The Society has an extensive collection of documents and photographs held in its secure archives. These are invaluable for members wishing to study the local history of the area or wishing to gather information for e.g. the Village Atlas Project. Please click on the tag above to see the catalogues. Anyone wishing to access the archives should contact the Society's Archivist, Julia Day.
Please click on the Latest Newsletter page to see information for the current month.
This is temporarily unavailable due to Covid restrictions. Anyone wishing to ask about publications please use the contact form


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Minneapolis, MN -- (SBWIRE) -- 02/13/2013 -- Casa Xelaju is pleased to offer an alternative Spanish curriculum for intermediate to advanced students who want to learn more about the current events in Guatemala. Studying these events will introduce a historical perspective based on internal and external affairs that have shaped Guatemalan society up to the 21st century.
For 25 years, our teachers and administrative staff have been researching articles published in major newspapers, academic magazines, universities, non-government publications and think-tank organizations to use as a resource to produce this didactic curriculum.
The use of the alternative curriculum in the Spanish immersion program
Is based on two premises. The first is that the student will develop a better understanding of social and economic issues relating to gender equality, poverty, race discrimination, government corruption and repression, the implications of US neo-policies in Guatemala, controversies regarding drug trafficking and more.
Ultimately, this program allows students to master their written and oral comprehension in Spanish using Steven Krashen's Comprehensive Input. As you might know, Comprehensive Input methodology is widely accepted and implemented in ESL programs at universities in the world. Our director, Julio E. Batres, has participated in several of Krashen's workshops in the USA. He has modified this methodology to apply it to our Spanish immersion program in Quetzaltenango, Guatemala.
About Casa Xelaju
At Casa Xelaju, our team has a strong commitment to continuously updating our methodology and to improving our curriculum to make your linguistic experience a complete success while also learning more about Guatemala society.
If you are interested in this alternative curriculum, please inform your Spanish teacher.
Julio E. Batres
Copyright © 2005-2013 - SBWire, The Small Business Newswire - All Rights Reserved - Important Disclaimer
Contact Us: 888-4-SBWIRE (US) - _PHONE_ (International)


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WASHINGTON (WUSA) --- To become one of the scientists of the future, sometimes you have to learn lessons about what took place millions of years ago. Some young people are doing just that at the Smithsonian's Museum of National History in Washington, D.C.
Tiffany Munos-Cegarra may be the only teenager but she get to work with some of the most talented scientists in the world there. She is working with ancient mollusks found in New Jersey. Handling something more than 60 million years old can be tricky, she told us.
"You have to be delicate because they can fall apart," shared Tiffany.
She is part of the paid internship Youth Engagement Through Science (or Y.E.S.). Y.E.S. students can connect with up to 500 scientists working with the Smithsonian.
Dr. Jocelyn Sessa with Smithsonian's Museum of Natural History said, "What's cool about Y.E.S. is that we're getting high school students, students at a younger age to see that science is something that can do and science is fun and interesting."
It translates to the younger students as well. The Smithsonian's Shari Rosenstein Werb said, "Young people are here with their families and they peek in the window and they see somebody like Tiffany, working on bones and excavating and a young person will look at them and say 'wow, she is just a few years older than I am. I can do that!'"
Well, as long you're careful: Remember these artifacts are tens of millions of years old.
School is just getting started and so is a new season of Cool School. We need some great story ideas so send them to Mike Hydeck at _EMAIL_


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How your camera's focus bracketing system works & how to create sharp stacked photos
posted Tuesday, February 28, 2023 at 11:30 AM EDT
Focus stacking, combining images shot at different focus distances to create a composite image with greater depth of field, isn't new. For years, photographers have used specialized software, like Helicon Focus and Zerene Stacker. However, this approach has required photographers to adjust focus and capture consecutive shots manually. Recently, cameras have begun incorporating focus bracketing modes to capture the requisite images for a focus stack automatically. Some cameras can even combine and stack images in-camera. For modern cameras with focus bracketing systems, how do they work, and are they as good as doing the focus bracketing yourself? Over at Lensrentals, photographer and all-around digital photography expert Jim Kasson answers these questions and more.
There's no doubt that focus stacking has helped photographers capture brilliant images. Not only does focus stacking extend the depth of field of images, but the technique also allows photographers to use their lenses at optimal apertures rather than stopping way down to increase the depth of field. On the other hand, the process is tedious at best and extremely difficult at worst. When working with high-magnification lenses up close, the depth of field is razor-thin. It is challenging to adjust focus the optimal amount over and over. Dedicated equipment such as focusing rails can help, but that adds another layer of complexity – and cost.
Enter camera manufacturers and their latest mirrorless cameras. Nikon has Focus Shift Shooting. Fujifilm, Olympus, Hasselblad, Sony, and Canon have Focus Bracketing. Whatever it's called, the feature takes the frustration out of capturing images for focus stacking. However, as Kasson writes, documentation about the feature is sometimes cryptic, and using the focus bracketing modes is only sometimes intuitive. There are many questions about how in-camera focus bracketing systems work and the best practices to achieve optimal results.
Kasson explains that Nikon and Fujifilm's systems work in a similar way. Considering the issue that must be overcome – limited depth of field – Nikon and Fuji deal solve it by successively moving the plane of focus further from the camera. In Kasson's diagrams above and below, he's sketched how sharpness can vary with distance at each focal plane distance. The "haystacks" show that "as you move further away from the focal plane, sharpness at first falls off gradually, then rapidly, then gradually again," writes Kasson. The width of the haystacks corresponds to the f-stop of the lens used. As expected, when you increase the step sizes from one focal plane to the next, the planes of focus "become more separated" while the "haystacks" remain the same.
Ideally, the selected step size ensures that the worst-case sharpness in a completed set of focus bracketing images is acceptable without shooting many extra, unnecessary images. Kasson writes that the first rule of focus bracketing is "All calculations of the desired step sizes should stem from choosing the minimum acceptable sharpness, and picking step sizes that are small enough to give you the sharpness you desire, and not so small that you waste a lot of exposures getting the job done."
Consider lens focus differently. Given static focus, what happens when you move the target? When the focal point is in front of the image sensor (red lines in the diagram below), the subject is considered "back-focused." If the focal point is behind the sensor (blue lines), the subject is "front-focused." When the focal plane falls precisely on the image sensor (black lines), the subject is "in focus."
This diagram helps illustrate the importance of "image space." As Kasson says, " If we concern ourselves with what happens on the sensor, or image side of the lens, we talk about image space and depth of focus." Focus bracketing systems like Nikon's and Fuji's work in image space. What's significant about this is that image space has nothing to do with the lens itself. After all, it deals with what's happening on the image side of the lens, not the lens itself. These focus bracketing systems ignore the focal length of the lens and subject distance, although they do consider the f-stop.
Concerning print sharpness, focus bracketing systems don't need to deal with focal length or subject distance. It's possible to reasonably model normal photographic lenses using an image of the diaphragm opening, which is approximately a circle. Kasson writes, "For most of today's lenses, that means we're talking about filled-in blur circles called circles of confusion (CoC). The thing that determines how much blur we'll see in the image is the diameter of that circle. The size of the CoCs, which are illustrated in the lower part of the above figure. Note that no matter whether the image on the sensor is front-focused or back-focused, the size of the CoC is determined by the amount of misfocusing on the sensor side of the lens (in image space). If you will forgive a bit of math, the diameter of the CoC is the amount of image space misfocus over the f-stop, but you don't even need to know that; the camera will figure that out for you."
With modern high-resolution image sensors, what's an acceptable CoC? For 35mm film cameras, depth of field tables were calculated using a 0.03 mm CoC diameter. That's too large for modern cameras, and sticking with that standard results in blurry images. CoC diameter these days is measured in micrometers (µm). There are 1,000 µm to a mm. The sensor pitch for a high-res camera is around 4 µm, so to achieve "roughly equal contribution of sensor and pixel aperture blur and defocus blur, you'd set the CoC for depth of field computations to about 4 µm," says Kasson. This results in depths of field considerably smaller than typical DoF tables.
Kasson describes the next rule of focus bracketing as follows: "Depending on your subject matter, the size of your intended prints, and the esthetics of the scene, I recommend using 15 µm as a default, and 7.5 µm for the parts of the image that you want to look reasonably sharp. If you want the most out of your camera, the right worst-case CoC for stacking and focus bracketing is on the order of the pixel pitch of the camera, or about 4 µm for high-res cameras. If you want the ultimate precision, you could go as low as half that with modest improvement. For non-critical work, twice that will be just fine."
When working with focus bracketing in your camera, you can select step size. This is a direct way to affect the circle of confusion. How do shot-to-shot CoCs change with camera settings?
Returning to image space, check out the diagram below. "The red circle indicates the blur circle in the sensor plane for an object in the near plane when the camera is focused on the middle plane. Let's call that the single-step-CoC. When you use focus bracketing, what controls its diameter?" If you guessed that the focal length, focus distance, or even the f-stop controls that diameter, you're wrong. Join the club. The only thing that affects the diameter of the single-step-CoC is the step size. When working in image space, the step size in micrometers will remain constant throughout an entire series of focus-bracketed images.
You can consider the step size, and select the optimal step size, solely based on the acceptable blur circle.
Putting that into real-world terms, Kasson considers the GFX series cameras, all of which include in-camera focus bracketing (some earlier models, like the GFX 50S, added this feature via a firmware update). "With the Fujifilm GFX 50, GFX 50R, GFX 50S II, GFX 100, and GFX 100S, it's really simple: the single-step CoC in µm is twice the step size, which means that the size of the largest blur circle you're going to see in a stack from a set of captures (the worst-case CoC) is the step size in µm. Step size = 1 means you'll not need to use an image with CoC of over 1 µm, which is ridiculously small for a 3.72 µm camera. Step size of 4 means that the largest blur circle you'll have to take is 4 µm, which is about the pixel pitch, and not a bad place to start. With a step size of 10, you'll have to use blur circles as large as two and a half times the pixel pitch, which is starting to get a bit sloppy. If you want to see the experimental results for the GFX 100, look here."
That's a lot of detailed technical information. So, how do you put all that into practice? At Lensrentals, Kasson explains, in easy-to-follow steps, how to put focus shift systems to work for your photography, regardless of the camera system you use. Kasson works through a real-world example, offers practical tips, and explains precisely how to select the optimal


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It didn't take long for Joshua Wyche to confirm the success of an outreach effort to encourage COVID-19 vaccination in his community.
Wyche, assistant vice president for strategic planning and pharmacy services at Augusta University (AU) Health in Georgia, appeared with Charles Goodman, pastor of the Tabernacle Baptist Church, in a February educational video to talk about vaccination.
Wyche and Goodman told viewers at the outset that they would focus on facts and tackle issues that undermined vaccine confidence in the majority Black local community.
Goodman shared his initial worries that the vaccines had been rushed into peoples' arms without adequate testing. That concern is real in Black and Brown communities, where memories of the infamous Tuskegee syphilis study foster ongoing mistrust of the healthcare system.
"We don't want to be the guinea pigs," Goodman said.
But he said physicians in his congregation had explained the COVID-19 vaccine testing process, allayed his concerns, and convinced him that vaccination was an expression of love for his neighbors.
During the February video, Wyche reinforced that message and talked with Goodman about the vaccines' benefits and the real and unfounded fears on which community members base their vaccination decisions.
Later that week, four young Black women came to an AU Health vaccination clinic and told Wyche that they went from "no" to "yes" on vaccination after watching the video.
"They felt educated and empowered," Wyche recalled in a July interview. He said he was delighted that he and the pastor got through to these young women and that they took the time to share their story.
Wyche said the video was effective because congregation members trusted their pastor's message about vaccination. As Goodman's invited guest, Wyche also became a credible source of information.
"It's got to be a very personalized, on the ground, trusted strategy to ultimately move the numbers where we want them to go for vaccination rates," Wyche emphasized.
But he also acknowledged that his community has "a long way to go" before everyone is protected against the virus.
The Georgia health department reported July 15 that 31% of residents of Richmond County, which includes Augusta, were fully vaccinated against COVID-19. Statewide, 39% of residents were fully vaccinated. According to the Centers for Disease Control and Prevention (CDC), preliminary data suggest that unvaccinated people account for nearly all recent U.S. COVID-19 hospitalizations and deaths.
Wyche said a recurring misconception in the local community is that COVID-19 vaccines impair fertility, a myth that likely originated with a false claim that the spike protein targeted by the vaccines is present on the human placenta.
"The [viral] spike protein was constantly discussed by medical professionals and the lay media," Wyche recalled. But he said many people didn't understand that "the spike protein that's on the placenta and the spike protein associated with COVID-19 are completely different."
That myth was one of several Wyche and Goodman tackled in the February outreach video.
U.S. Surgeon General Vivek H. Murthy on July 15 released a public health advisory about the threat of health and vaccine misinformation during the COVID-19 pandemic. He called health misinformation an "urgent threat" that requires action at all levels of society.
Wyche said that along with countering misinformation, clinicians need to inform patients about the known risks of COVID-19 vaccine-related adverse events, such as hypersensitivity reactions.
He said it's helpful to let patients know that immunizations they're already familiar with, such as influenza, pneumococcal, and varicella vaccines, can also cause hypersensitivity reactions.
At AU Health, he said, about 1 of every 700 patients has a hypersensitivity response to their COVID-19 vaccine. The reactions typically resolve on their own or after a dose of diphenhydramine. He said that of the tens of thousands of people the health system has vaccinated, fewer than five have required hospitalization for a hypersensitivity response.
"So we [say] yes, there is a chance of this, but it's incredibly low," he said.
Risk communication needs change as new information becomes available, such as the recent reports of myocarditis and pericarditis in young adults and adolescents who received mRNA-based COVID-19 vaccines.
Wyche said these conversations with patients are challenging.
"The information is always going to be a bit more heightened when you're talking about an adolescent population," he explained. A key fact to convey, he said, is that vaccine-related myocarditis is rare and typically resolves within a couple weeks.
The CDC emphasizes that the risk of serious illness and death from COVID-19 far outweighs the risk of vaccine-related myocarditis and pericarditis. The agency recommends COVID-19 vaccination for everyone age 12 years or older.
Martin Bishop, clinical pharmacy specialist in ambulatory care and population health at Johns Hopkins Hospital in Baltimore, Maryland, said in early July that his patients hadn't yet raised concerns about vaccine-related myocarditis.
Nonetheless, the clinical and pharmacy team has created written information about myocarditis and standard talking points for hospital staff to refer to in conversations with patients. Bishop said the health system makes this and other vaccine information available centrally for all staff so everyone has access to standard, up-to-date documentation.
But he cautioned that handing out a "one-pager" of vaccine information is no substitute for a face-to-face conversation tailored to a patient's specific concerns. He said that's the case "even if what you're relating to the patient is identical to that [written] information."
Bishop said the most common COVID-19 vaccine question he gets from patients is about the risk of blood clots associated with the Johnson & Johnson–Janssen vaccine. Answers to these questions are largely based on information from the manufacturer and CDC.
Bishop said some people who come to vaccine clinics aren't sure that they want to get vaccinated.
These people, he said, usually have "very specific ... questions about their particular circumstances." He emphasized that clinicians need to address each concern to ensure that the patients follow through and get vaccinated.
Because some patients are uncomfortable about the emergency use authorization process through which COVID-19 vaccines were made available, Bishop reeducated himself about vaccine licensing and clinical trial design. With that refresher, he's better able to talk with patients about those processes as well as product-specific issues related to the vaccines.
Bishop said that when the health system began staffing mass vaccination clinics, the onsite team had to reassure some community members about the content and integrity of vaccine doses.
"We tried our best to have the preparation of all these doses visible. And if anyone had questions about how they were prepared, or whether room temperature or cold chain stuff was maintained appropriately, we would tour patients through those activities as often as we could to make sure ... everyone had a comfort level with what we were doing," Bishop said. He said this seemed to reassure people that there were "no microchips, no 5G, none of that stuff" in the vaccine doses.
Bishop said rumor-based concerns like those have lessened over time.
"Most questions have gone from the tough-to-disprove conspiratorial to quite clinical concerns about side effects, things based in data, which is refreshing," he said. "Those are easier to talk about because you can actually point to evidence. It's tough to disprove there's no microchips in there."
ASHP is a partner in the Get the Medications Right™ Institute's National Task Force on building vaccine confidence and participant in federal efforts to boost COVID-19 vaccine uptake. Learn about the task force's work and ASHP's free tools regarding the pandemic, including our COVID-19 Vaccine Confidence Toolkit and Assessment of Evidence for COVID-19-Related Treatments. Additional information is available at ASHP's COVID-19 Resource Center and the COVID-19 Community at ASHP Connect.
[This news story will appear in an upcoming issue of AJHP.]


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Time Lapse: Scituate Reservoir construction began 100 years ago
The Providence Journal
It was 100 years ago this year that construction began on the Scituate Reservoir, which provides water to a large portion of Rhode Island. It was the biggest public works project in the state at the time. Several villages, including Kent, were taken over by the project. Residents' homes were purchased by the government, even though some residents were reluctant to leave. It took about five years of construction before the reservoir began holding water for use by Providence and many other cities and towns.
More:Time Lapse: "C" how well you can do on 1936 puzzle


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The SECURIPLEX Water Mist system is a highly effective extinguishing system that uses water and air to generate a fine water droplet. The Water Mist system uses less water than standard sprinkler systems and provides equivalent or better extinguishing characteristics than gas but without hazard to personnel. Specifically, the Water Mist's unique characteristics provide the user with:
Low water discharge
The Water Mist system uses less water per discharge than any conventional sprinkler. Post-discharge cleaning time is therefore negligible and consequential damages and losses are minimized. Operations can resume in the shortest time possible.
Highly effective extinguishment
The Water Mist system extinguishes the fire in seconds and, unlike gaseous systems, is highly effective even though limited ventilation is present.
Enviromentally friendly and safe for personnel
The Water Mist system simply uses water and air, which cause no potential risk for the environment or for personnel. Therefore the evacuation of personnel before a system discharge is not essential.
The SECURIPLEX FIRE SCOPE® 2000 Water Mist system operates at a low pressure of 75-85 psig which allows the use of standard piping and the connection to the plant water and air supply, when available. This provides almost unlimited protection time and eliminates the need for water tanks or bottles. Maintenance cost is therefore greatly reduced
Twin fluid technology uses large water pathway nozzles. Mist is generated by air impingement as opposed to small orifices therefore minimizing the risk of nozzle clogging. The SECURIPLEX FIRE-SCOPE® 2000 water spray system is typically supplied as a fully integrated system including, control, detection and extinguishment, however the FIRE-SCOPE® 2000 can be integrated with an existing detection system.
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1. Engineering
 2. Computer Science
 3. here is the declaration of a struct for the nodes...
Question: here is the declaration of a struct for the nodes...
Question details
Here is the declaration of a struct for the nodes in a singly-linked list: typedef struct intnode int value; struct intnode next; } intnode_t; A function named remove odds takes one argument, a pointer to a linked list in which 0 or more nodes contain odd integers: intnode t remove odds (intnode t *head); The function removes all the nodes containing odd integers from the linked list. The remaining nodes (the ones containing even integers) must remain in the same order that they appear in original linked list. The function returns a pointer to the first node in the modified linked list. For example, suppose variable my_list points to this linked list: my_list 2 and remove_odds is called this w mylistremove_odds (my_list); After remove odds returns, the modified list looks like this: my list remove_odds should return an empty linked list if it passed an empty linked list or if all the nodes contain odd integers. Your remove odds function can call functions from the C standard library (see the crib sheet at the end of this question paper); however, it cannot call any of the linked list functions that were developed in lectures and labs. No marks will be awarded for a solution that allocates new nodes or copies values from one node to another Marks wil be deducted for code that performs more traversals of the linked list than are necessary
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Prominent Syrian human rights lawyer released
A prominent Syrian human rights lawyer, Haitham Maleh, has been released by the Syrian authorities. Mr Maleh was given a presidential pardon, says a Syrian human rights organisation.
Haitham Maleh was sentenced to three years in prison last July for "weakening the national moral principles". He was arrested after criticising the government on television. He had campaigned for many years for the country's state of emergency to be lifted. The state of emergency was imposed when the Baath Party took power in 1963. The leaders of the party also imposed repressive rule which has continued until today partly thanks to the repressive measure.
In 2006, Mr Maleh received a Dutch human rights award the Geuzenpenning - Beggars' Medal, which refers to 16th century freedom fighters and a World War II resistance group - the Geuzen. The medal is awarded every year to people or organisations who strive for democracy, or against dictatorship, racism and discrimination. In the 1980s, Haitham Maleh was a political prisoner.http://cdn.radionetherlands.nl/data/files/images/lead/maleh.jpg
© Radio Netherlands Worldwide


Busting 8 Myths About Rio's Favelas
As hundreds of thousands of foreign visitors descend on Rio de Janeiro in August to watch the Olympics, there is no doubt that many curious eyes will be gazing up at the well-known informal neighborhoods called favelas. There has been a lot of media mention of the favelas, from famous movies to a recent surge because of the Olympics, but there are a lot of misconceptions. Through this post, we will break down 8 commonly held myths or generalizations about favelas and why they aren't quite true.
1. Myth - "Favelas are 'Slums'"
Catalytic Communities / Via Flickr: catcomm
If you type "favela" into Google Translate, the resulting word is "slum" or "shanty town". The word favela comes from a plant that grows in the Northeast of Brazil. When the first favela was founded in the late 1800's, it was named "Favela Hill" after the plant. Today, that favela still exists and is called Providência, in Rio's Port region. The only reason we use "slum" as a translation for "favela" is to find an easy way to relate it to something familiar in our own cities. Unfortunately, this translation brings connotations of poverty, precariousness and lack of safety. While some favelas have "slum-like" conditions, it is incorrect to generalize that favelas are slums because many of them have sturdy homes, commerce, and middle-class residents.
2. Myth - "All Favelas are the same"
Catalytic Communities / Via Flickr: catcomm
There are more than 1000 favelas in Rio de Janeiro alone that hold more than 20% of the city's population. Just to give a sense of scale, that is over a MILLION people. Favelas come in all shapes and sizes and have incredibly rich histories. Favelas like Rocinha, City of God, Complexo de Alemão (German Complex) or Maré have tens of thousands of people within them and can have smaller subsections that indicate neighborhoods within neighborhoods. Others are smaller and are small enough where everyone knows each other. In the touristy South Zone, almost all of the favelas are on very steep hills that rise over the city, but in the North Zone and West Zones of the city (which are much larger) the land is flatter, which means they are built differently and have different assets and challenges.
3. Myth - "All favelas are illegal"
David Morsi - Catalytic Communities / Via Flickr: catcomm
In fact, there are some favelas that have legal protections under Brazilian state and national laws. Additionally, during the 1980's Rio's governor Brizola gave some communities (Like Vila Autódromo (shown above) and Vila União de Curicica that were evicted for the Olympic games… awkward…) legal recognition to stay on the land by the state. Even beyond this, Brazil's constitution actually offers one of the most generous "adverse possession" protections in the world, which basically means that if you can prove you have lived on land for 5 years without someone trying to kick you off, you have a right to the land. Just based on this claim alone, many of the favelas would have legal status, but the bureaucratic, costly and lengthy process usually isn't worth the struggle for residents. Throughout the history of favelas, there have been policy initiatives to offer land titles to favela residents, though these were largely unsuccessful on large scales because of the inefficiency of the government to implement the programs.
4. Myth - "All favelas are dangerous"
David Morsi - Catalytic Communities / Via Flickr: catcomm
This is a complicated claim. Yes, it is important to recognize that there are issues within favelas like drug trafficking and police violence, but as little as 1% of favela residents are involved in drug trafficking. However, as we mentioned above, there are 1.2 MILLION PEOPLE living in the favelas. To say that the places where 1.2 MILLION PEOPLE live are dangerous would be a gross generalization that completely dismisses all of the qualities, innovations and positive qualities of these places. Further, believing this over-generalization allows policies to be made that further stigmatize the communities. It is also important to understand that this "violence" that occurs within favelas is not inherent, rather a result of the DECADES of neglect from the government that have left the poorer folks in Rio without basic services.
5. Myth - "All Favela tours are bad"
Catalytic Communities / Via Flickr: catcomm
This, too, is a complex answer. First of all, don't be an idiot and take a jeep tour through a favela. This is not a jungle, you are not going into the wild unknown, and by giving in to your fear, you are just perpetuating a very real problem of stigmatization of these neighborhoods. If you are going to take a tour, you must choose carefully. Take a tour led by a resident to understand the realities and history of these communities. It is possible to tour a favela and try and learn the deep, complex, rich, and wonderful histories that created them. Why did people settle here? Where did the people come from? Who were the first settlers? How did the favela grow? Who are the main leaders? What kinds of social projects exist in the community? What are they most proud of? What does _______ community mean to residents? Although these are the poorer neighborhoods, they are still neighborhoods. If you choose carefully and learn the local expertise, you actually will have a really unique opportunity to learn.
6. Myth - "Homes in Favelas are shoddily built"
David Robertson - Catalytic Communities / Via rioonwatch.org
This is a very common misconception about favelas and it emerged because of the direct translation of "slum" and "shantytown", which both have connotations of precariousness. However, homes and structures in favelas are largely built with concrete, bricks, reinforced steel, rock and sand. They take years to build and residents usually over-build with the hopes of further expansion. Informality means the homes are built piece-by-piece. Residents save money, understand their needs, and build according to those needs. What might start out as a small home with one bedroom, one bathroom, a small kitchen and a living room could eventually turn into a structure with four homes, each with 2 bedrooms, a kitchen, a large living room and a bathroom. Further, since residents usually prioritize the inside of the home over the outside, the outside might seem unfinished, but the inside will be immaculately clean and have all the finishing touches.
7. Myth - "People want to leave and get out of favelas"
Catalytic Communities
There are some people who want to leave favelas, but there are also a large number of people who want to stay in their communities. Residents in favelas talk about how there is a very close knit community where everyone knows each other and this has value. Further, there are often generations of families that live in favelas, which makes them more significant than simply a collection of structure and an actual piece of history and memory. This misconception is detrimental because it means policies are made which see the existing favelas as worthless. The thought process is, "oh, if they all want to leave, then why should we invest in upgrading?" However, this is not the case and global policies regarding informal settlements are beginning to shift away from informal settlement removal to informal settlement upgrading and integration into the formal city.
8. Myth - "Rio would be better without favelas"
Catalytic Communities / Via Flickr: catcomm
As has been mentioned twice… just for emphasis… over 1 million people live in Rio's favelas. They are an integral part of the city and have been for over a century. They also have many qualities that are actually considered good by urban planners, such as density, walkability, mixed-use function, affordability, and the fact that they are spread out through the city near other more wealthy neighborhoods. For instance, Santa Marta is near Botafogo, Vidigal is near Leblon, Rocinha is near São Conrado and Gávea… you get the point. By highlighting qualities of favelas, it is clear that viewing them with terror or disgust is not productive or correct. Further, Rio has a huge affordable housing deficit, and if the favelas are considered a "de facto" affordable housing stock, suddenly the deficit doesn't seem so extreme. Rather than building completely new affordable housing, why not protect and upgrade what exists? The key is to give options to people who want to leave their current situation and to those who would rather that their community be upgraded.
What is a favela?
Rio's favelas have a fascinating history and the Olympics provide a perfect opportunity to learn more. It is impossible to generalize about the favelas because of their immense diversity of history. Even if you don't visit a favela, you will see them. Take this opportunity to educate yourself about the realities of these neighborhoods, the struggles they face, and the culture they bring to Rio's urban fabric.
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Blackspotted Rubberlip
Name: Blackspotted Rubberlip
Local name: Farsh
Scientific name: Plectorhinchus gaterinus
Classification: Class: ray-finned fishes; Order: perch-likes; Family: sweetlips (Haemulidae)
Size: It attains a total length of 50 cm.
The Blackspotted Rubberlip occurs in coral and rocky areas, inhabiting depths between 3 m and 55 m. By day, it is usually seen in stationary aggregations, close to reefs, often under coral ledges or near caves. It is oviparous with distinct pairing during breeding.
This species is restricted to the Western Indian Ocean, from the Red Sea and the east coast of Africa to the Gulf of Oman and the Arabian Gulf.
Conservation status:
It has not yet been assessed globally by the IUCN Red List of Threatened Species. In a recent regional assessment for the Arabian Gulf it was classified as Least Concern (LC). The species is mainly caught by handline and traps.
The body is oblong and moderately compressed, with a small, sub-terminal mouth and very thick lips. The dorsal fin has no notch between the spinous and soft portions. The caudal fin is rounded in young, becoming truncate in adults. The body coloration of adults is whitish to pale green dorsally, white ventrally, with numerous small black spots, which progressively become smaller ventrally. The head is dark grey, lighter ventrally, and the lips are bright yellow. Fins are yellow, and the dorsal and caudal fins are densely covered with black spots. Juveniles have three pairs of black stripes on the head and body, which break up into spots at a length of about 12 cm.