Good News: Anti-Microbial Gel Cuts HIV Infection Rates for Women | 80beats

Posted on by

HIV virusThere was a big step forward this week in the struggle to contain the spread of HIV and AIDS in sub-Saharan Africa. Reporting on a three-year study in the journal Science, scientists at the Centre for the Aids Programme of Research in South Africa (CAPRISA) say that a microbicidal gel reduced HIV infection rates in women who used it by 39 percent over the course of the study. It would be the first time such a gel has proven so effective.

The researchers gathered nearly 900 women for the study who were HIV-free but demographically at risk for infection. Half received the gel, half a similar-looking but inactive substance. Among those given the gel, a vaginally-administered substance that contained an antiretroviral medication called tenofovir, infection rate fell by half after a year, and were reduced by 39 percent over two and a half years.

“This is very encouraging,” said Dr. Michel Sidibe, executive director of Unaids, the United Nations AIDS-fighting agency. “It can be controlled by women, and put in 12 hours earlier, and that is empowering. They do not have to ask the man for permission to use it. And the cost of the gel is not high” [The New York Times].

Though subsequent trials will of course be needed, these first results are especially inspiring given the predicament of women in some of these nations.

Women fall victim to HIV/Aids in disproportionately large numbers – 60% of new infections in Africa are among women. Many in the poorest countries have little education and suffer from very low status, so are unable to negotiate safe sex, using a condom, with their partner [The Guardian].

Salim Abdool Karim, one of the study authors, said the product would cost women “just pennies,” which is crucial because the effectiveness goes up with the consistency of use.

“Boy, have we been doing the happy dance,” Dr Karim, from the University of KwaZulu-Natal in Durban, said [BBC News].

Related Content:
80beats: New HIV Hope? Researchers Find Natural Antibodies That Thwart the Virus
80beats: Researchers Track the HIV Virus to a Hideout in the Bone Marrow
80beats: S. African HIV Plan: Universal Testing & Treatment Could End the Epidemic
80beats: If Everyone Got An Annual AIDS Test, Could We Beat Back the Epidemic?

Image: iStockphoto


What’s in a (Species) Name? Maybe the Power to Fend Off Extinction | Discoblog

Posted on by

seapigletshrimpThe blue pepper-pot beetle, St. John’s jellyfish, and the queen’s executioner beetle–these distinctly British-sounding organisms share a few things in common. For one, they all have brand new names, thanks to the ingenuity of the British public.

The trio received these new names from public entries in a competition organized by The Guardian, Natural England, and the Oxford University Museum of Natural History. Other similarities include (perhaps unsurprisingly) that they all live in the UK, and that they’re all threatened with extinction.

One usually pictures an organism’s discoverer naming her find, or the organism’s common name coming from obvious characteristics (like lighting bugs or fireflies, for example), but sometimes critters just slip through the cracks; these ten were previously known only by their official scientific classifications. That made it hard, the competition’s organizers suspected, for the public to care whether or not these rare creatures disappeared. The naming competition, thought up by Guardian columnist George Monbiot, was meant to make the threatened organisms more identifiable and relatable to the public.

Comparing the cuddly appeal of the sea piglet shrimp (pictured above) vs Arrhis phyllonyx, it seems they accomplished their goal. The competition had over 3,000 entries, from which the judges picked a winner and two runners-up for each of the species based on how well the name matched the organism’s looks, habitat, and behavior. The naming competition’s overall winner was the queen’s executioner beetle, a black hooded bug from Windsor.

No matter who won, Monbiot sees the competition as a whole as a success.

“Judging the competition was very hard, as in every case there were at least half a dozen names that deserved to win…. Not only were they practical and distinctive, many of them also captured the magic and mystery of England’s wildlife.”

Related content:
Discoblog: What You Get When You Name a New Dinosaur Over Beers: Mojoceratops
Discoblog: To Do: Find New Bug Species on EBay, Name It After Self
Discoblog: Expert is Bugged Out By Insects as Terror Threat
Discoblog: Recently-Discovered Carnivorous Plant Eats Bugs, Rats
The Loom: A Tapeworm To Call My Own

Image: Moskal, Wojciech /World Register of Marine Species


Intel Ships 3.2GHz Hexacore i7-970 Desktop CPU [Guts]

Posted on by

Intel's 32nm Gulftown architecture has produced its latest gem: the 3.2GHz hexacore i7-970 processor that'll set you back $900. In addition to being super speedy—especially with TurboBoost, which lets you rev up to 3.46GHz—you get 12MB of on-chip cache and a triple-channel DDR3 memory controller. Fun times, and something I wouldn't be at all surprised to see end up in the Mac Pro someday. [NewEgg Electronista] More »


That Mitchell look | Bad Astronomy

Posted on by

David Mitchell is one half of the brilliant British comedy team that makes the show "That Mitchell and Webb Look", which commonly has skeptical themes to its humor. Mitchell has a series of short videos posted on The Guardian, and he made one about global warming that, like everything he does, is fantastic. They don’t allow embedding — hey Guardian, it’s the 21st Century now! — so I’ll just link to it and let you have a look.

Tip o’ the thermometer to Arthur Taylor.


Audit Your MySQL Memory Usage

Posted on by

Matthew BoehmEver wonder why your MySQL server runs out of memory or your server starts swapping it like crazy? It could be that you are allowing too many connections or have a buffer that isn’t being used. Here are some simple formulas you can use to determine how much memory your MySQL server can use.

All of these variable values can be seen by using “SHOW GLOBAL VARIABLES” at the MySQL client prompt. They are given in bytes so you must convert to KB, MB or GB by dividing the value returned by 1024, 1048576 or 1073741824, respectively.

Remember: Each connection from your application is referred to as a thread by MySQL.

Per-Thread Memory Use (The amount of memory a single connection can use):

read_buffer_size + read_rnd_buffer_size + sort_buffer_size + thread_stack + join_buffer_size

Example: 1048576 + 2097152 + 1048576 + 262144 + 131072 = 4587520 bytes
Divide that by 1048576 to get the usage in MB, and you find that each thread can use up to 4.375 MB of memory.

Now, take that amount and multiply by your max_connections, and you’ll find the total potential memory usage. For this example, let’s set max_connections to 350. The example server could use 1,531.25 MB or 1.49 GB if all 350 connections were in use at a given time. If we have 4GB of RAM in the server, that accounts for almost one third of our available memory.

And that’s not all! There are several other “global buffers” that MySQL creates depending on which table engines you are using. The formula below assumes you have a mix of MyISAM and InnoDB tables and you are using the query cache:

Base MySQL Memory Usage

key_buffer_size + max_heap_table_size + innodb_buffer_pool_size + innodb_additional_mem_pool_size + innodb_log_buffer_size + query_cache_size

Example: 1073741824 + 33554432 + 2147483648 + 134217728 + 10485760 + 536870912 = 3936354304 bytes
To get the usage in GB, we divide by 1073741824 and see that 3.66 GB is being used!

Again, in a 4GB server, base MySQL – with no connections – can use 3.66GB, or about 90 percent of my server’s physical memory. Yikes! When you see that, your first move should be to contact your sales rep to get more memory installed. We advise, for system stability, never to assign more than 80 percent of overall system memory to MySQL (or any process for that matter).

One other area to check for memory reduction is your client application code. While the PHP manual says you don’t have to explicitly call mysql_close or mysqli_close, we highly recommend it as a best practice because there’s a known PHP bug that prevents connections from being properly closed on script termination. And if each connection to MySQL eats up a base amount of memory whether it’s being used or not, your server will suffer for no reason.

-Matthew, CMDBA 5.0

StumbleUpon
Twitter
DZone
Digg
del.icio.us
Technorati