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friday :: march 31, 2006
   
 
menstrual blood: alternative source of stem cells

Researchers have harvested stem cells from human menstrual blood. These stem cells could potentially be a source of specialized heart cells, which might be used to treat failing or damaged hearts. When the stem cells were cultured in a way to induce them to become heart cells, after five days about half of the cells contracted 'spontaneously, rhythmical and synchronously, suggesting the presence of electrical communication' between the cells. They behaved like heart cells. Researchs said they were able to obtain about 30 times more stem cells from menstrual blood than from bone marrow, which remains the most common source of adult stem cells.

Some previous research on the efficacy of stem cell therapy for heart repair has shown benefit from mesenchymal stem cells (often found in bone marrow), but mostly because assist in the growth of new blood vessels. The true benefit of stem cells to heart function, however, may be in promoting cardiomyogenesis (the growth of cardiac muscle). To achieve this, the source of the cells needs a high rate of cardiac activity and similar gene and protein expression. In two studies presented from researchers at the Keio University School of Medicine in Japan, new sources from menstrual blood-derived endometrial cells and umbilical cord blood-derived mesenchymal cells show significant promise in this function.

In the first study, the team collected menstrual blood from six women to obtain a sample of endometrial cells. The researchers found that approximately half of this cells contracted simultaneously, suggesting an electrical communication between the cells. Further analyses of the cells revealed appropriate cardiac gene expression and action potential, as well as sustained and significant positive cardiac troponin-1, a calcium-regulated protein in muscle tissue, and connexin 43, a protein that assists in intracellular interactions The in vitro data suggests that stem cells from this source have significant cardiomyogenesis potential and are potentially valuable not only because they can be easily collected from young volunteers, but also because of their collection-efficacy. A single sample of the menstrual blood returns a large number of stem cells.

"We believe that by looking at these new sources for stem cells, we will eventually be able to use our own stem cells to repair our own heart dysfunctions," said Sunichiro Miyoshi, M.D., of the Keio University in Japan, and one of the lead authors of the study. "The value of finding new sources is in finding younger and stronger stem cells."

Human Menstrual Blood Derived Stem Cell Has a High Cardiomyogenic Potential; Possible New Cell Source for Cardiac Stem Cell Therapy (Abstract 921-105) >from *Potential heart benefit found in stem cells*. Researchers find viable new sources for stem cell transplants to the heart. March 12, 2006

related context
>
female cycle and brain expansion. november 18, 2005
> biology of gender: defining male and female. may 6, 2005
> intelligence in men and women. february 4, 2005
> were african women our first mathematicians?. march 8, 2002
> blood relations. menstruation and the origins of culture by chris knight. 'as they harmonised their rhythms with those of the world around them, earliest cultural women must have felt the power in their own bodies to be intimately connected with all wider processes of cyclical renewal.' 1995

imago
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my period for my heart

sonic flow
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inducing stem cells [stream]
inducing stem cells [download]

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friday :: march 24, 2006
   
 
medical ethics and guantanamo bay

"We write regarding the forcefeeding and restraint of Guantanamo Bay detainees currently on hunger strike.1,2 The World Medical Association specifically prohibits forcefeeding in the Declarations of Tokyo and Malta, to which the American Medical Association is a signatory.

Fundamental to doctors’ responsibilities in attending a hunger striker is the recognition that prisoners have a right to refuse treatment. The UK government has respected this right even under very difficult circumstances and allowed Irish hunger strikers to die. Physicians do not have to agree with the prisoner, but they must respect their informed decision. Those breaching such guidelines should be held to account by their professional bodies. John Edmondson (former commander of the hospital at Guantanamo) instigated this practice, and we have seen no evidence that procedures have changed under the current physician in charge, Ronald Sollock.3

Edmondson, in a signed affidavit, stated that “the involuntary feeding was authorized through a lawful order of a higher military authority.”4 This defence, which has previously been described as the Nuremberg defence,5 is not defensible in law. In a reply to an earlier draft of this letter, Edmondson said that he was not forcefeeding but “providing nutritional supplementation on a voluntary basis to detainees who wish to protest their confinement by not taking oral nourishment”.

Recently, it was confirmed that health-care staff are screened to ensure that they agree with the policy of forcefeeding before working in Guantanamo Bay.1 On his departure, Edmondson was awarded a medal for his “inspiring leadership and exemplary performance [which] significantly improved the quality of health care for residents of Guantanamo Bay” and “scored an unprecedented 100% on both the Hospital and the Home Health surveys.”3 The New York Times, however, reports that hunger striking detainees are strapped into restraint chairs in uncomfortably cold isolation cells to force them off their hunger strike.2

We urge the US government to ensure that detainees are assessed by independent physicians and that techniques such as forcefeeding and restraint chairs are abandoned forthwith in accordance with internationally agreed standards.

We declare that we have no conflict of interest."

David J Nicholl, Holly G Atkinson, John Kalk, William Hopkins, Elwyn Elias, Adnan Siddiqui, Ronald E Cranford, Oliver Sacks, on behalf of 255 other doctors

1 Okie S. Glimpses of Guantanamo: medical ethics and the war on terror. N Engl J Med 2005; 353: 2529–34.
2 Golden T. Tough US steps in hunger strike at Camp in Cuba. New York Times Feb 9, 2006 (accessed Feb 22, 2006).
3 Byrington S. Sollock takes command of Naval Hospital. Guantanamo Bay Gazette 2006; 63: 3. (accessed Feb 22,2006).
4 Al Joudi et al vs George Bush in the US District Court for the District of Columbia. Case1: 05-cv-00301-GK. Document 48, Exhibit A. Filed Oct 19, 2005.
5 Spitz V. Doctors from hell: the horrific account of Nazi experiments on humans. Boulder: First Sentinent, 2005. >from *Forcefeeding and restraint of Guantanamo Bay hunger strikers* March 10, 2006. Lancet 2006; 367: 811


related context
>
jtf-gtmo. 'joint task force guantanamo conducts detention and interrogation operations to collect and exploit intelligence in support of the global war on terrorism, coordinates and implements detainee screening operations,and supports law enforcement and war crimes investigations.'
> guantánamo bay - a human rights scandal. 'the unlawful detention of 'enemy combatants' has now entered its fifth year... guantánamo bay has become a symbol of injustice and abuse in the u.s administration’s 'war on terror'. it must be closed down.' amnesty international
> black sites. 'a military term that has been used by intelligence agencies to refer to secret prisons, generally outside of the mainland territory and legal jurisdiction, and with little or no political or public oversight.'
> the national security strategy. 'america is at war.' u.s national security council. march, 2006
> situation of detainees at guantánamo bay. united nations, commission on human rights. february 16, 2006
> mortality before and after the 2003 invasion of iraq. november 19, 2004
> deadly medicine. 'how could science be co-opted in such a way that doctors as healers evolved into killers and medical research became torture?' november 5, 2004
> art and war: the role of artists and scientists in times of war. 'what can artists and scientists do when there is a war? how can we be useful? how can we help to find solutions? how can we avoid the use of the military while at the same time protecting the lives of innocent civilians? what educational work can we do to avoid violence and war?'

imago
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guantanamo ethos: the place of living ?

sonic flow
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involuntary feeding [stream]
involuntary feeding [download]

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friday :: march 17, 2006
   
 
democracy: the free and open source internet tv platform

The Participatory Culture Foundation was born in February 2005 with a mission to facilitate a new, democratic mass medium through internet TV. Through free software and an expanding community of individuals and organizations, the Participatory Culture Foundation will be a catalyst for the democratization of online video, enabling a diversity of voices across the nation and the world.

The Participatory Culture Foundation (PCF) works with volunteers all over the world, including the open-source software community. PCF’s work has been made possible by seed funding from the Rappaport Family Foundation and Mitch Kapor’s Open Source Applications Foundation.

Problem: a closed-off video landscape for independent publishers
Internet TV is quickly becoming the next mass medium, as more websites feature video content, thousands of people tune in to daily video blogs, and millions of people watch “viral” videos online. Television is the defining medium of our culture and it is moving online.

But until recently, there’s been no easy way for individuals and grassroots organizations to fully participate in this emerging mass medium. Major software, web, and media companies are spending millions of dollars developing closed-off internet TV players that only accommodate proprietary video content and freeze out independent publishers.

Democracy: open and independent internet TV
PCF has built an internet TV platform that covers the whole equation, from publishing to viewing to sharing video, with software that is free, open-source, and open to everyone. For individuals and organizations, the PCF platform provides instant video capacity and dramatically levels the playing field, allowing anyone to publish high-quality video to 50, 5,000, or 500,000 people – with virtually no cost. It is crucial for the public interest that that the PCF platform exists as an open and independent alternative to closed and proprietary commercial players.

On February 21st, 2006, PCF conducted the full launch of our flagship product, the DTV video player, including new versions for Windows and Linux and an updated Mac version, with a new name: Democracy. PCF unveiled a supporting community website -- GetDemocracy.com – dedicated to the peer-to-peer spread of the Democracy platform. The Democracy platform is entirely free, opensource (VLC, Xine, Bit Torrent, and Mozilla just to name a few), and built on open standards.

In addition, PCF has done outreach to groups that need this video capacity the most: independent media, non-profits, grassroots organizations, community access television, citizen journalists, public education, independent video creators, bloggers, and more. Democracy: internet TV will birth new types of video programming and facilitate a diversity of voices and opinions in civic discourse. We’re working to ensure that the emerging medium of internet TV is open and independent, one where anyone can create and everyone can watch. >from *GetDemocracy site.

related context
>
indymedia. the independent media center
> you tube. broadcast yourself
> open source software for public broadcasters.
> ourmedia: do-it-yourself media. march 25, 2005
> urballon: an urban media space. october 8, 2004
> think tools for revolution > reclaim the streams!. september 17, 2004
> manifesto of urban televisions: open access television. april 23, 2003
> weblog, a new flow of information. may 15, 2002
> smart mobs: new uses of mobile media. october 3, 2002


imago
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escape from old tv: publish + view + share

sonic flow
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enabling a diversity of voices [stream]
enabling a diversity of voices [download]

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friday :: march 10, 2006
   
 
global evolutionary map

In 1870 Ernst Haeckel mapped the evolutionary relationships of plants and animals in the first 'tree of life'. Since then scientists have continuously redrawn and expanded the tree adding microorganisms and using modern molecular data, yet, many parts of the tree have remained unclear. Now a group at the European Molecular Biology Laboratory [EMBL] in Heidelberg has developed a computational method that resolves many of the open questions and produced what is likely the most accurate tree ever. The study gives some intriguing insights into the origins of bacteria and the last common universal ancestor of all life on earth today.

"DNA sequences of complete genomes provide us with a direct record of evolution", says Peer Bork, Associate Coordinator for Structural and Computational Biology at EMBL, whose group carried out the project. "For a long time the overwhelming amount of data [the human genome alone contains enough information to fill 200 telephone books] has made it very difficult to pinpoint the information needed for a high-resolution map of evolution. But our study shows how this challenge can be tackled by combining different computational methods in an automated process."

Bork's lab specialises in the computational analysis of genomes, and recently they applied this expertise to the tree of life. Since all organisms descend from the same ancestor, they share some common genes. Francesca Ciccarelli and Tobias Doerks of Bork's group managed to identify 31 genes with clear relatives in 191 organisms, ranging from bacteria to humans, to reconstruct their relationships.

"Even using such genes, you might get the wrong answer," says Ciccarelli. "Organisms inherit most genes from their parents, but over the course of evolution, a few have been obtained when organisms swapped genes with their neighbours in a process called horizontal gene transfer. Obviously, the latter class of genes does not tell you anything about your ancestors. The trick was to identify and exclude them from the analysis."

"This procedure drastically reduced the 'noise' in the data, making it possible to identify as yet unknown details of early evolution," says Tobias Doerks. "For example, we now know that the first bacterium was probably a type called gram-positive and likely lived at high temperatures – suggesting that all life arose in hot environments."

The improved tree has also shed light on other research carried out by the group. Bork and colleagues are participating in projects that collect genetic material of unknown species en masse from environments such as farm soil and ocean floor. "With the new high-resolution tree in hand, it is now possible to classify genetic material from this unexplored microbial world and further our understanding of life on the planet." >from *A new tree of life allows a closer look at the origin of species. A global evolutionary map reveals new insights into our last common ancestor. March 2, 2006

related context
>
proteus. a nineteenth century vision. 'the central figure of the film is biologist and artist ernst haeckel (1834-1919)'. january 6, 2006
> a map of recent positive selection in the human genome. march 7, 2006
> constructal law explains animals' running, flying and swimming. january 6, 2006
> evolution of conditional cooperation in humans. december 30, 2005
> diversity: there’s more than one way of doing things. july 9, 2004
> evolution of symbolic thinking. april 6, 2004
> human origins: gene mutation linked to evolution. march 26, 2004
> challenges to evolution education. november 14, 2003
> cooperation evolution. october 8, 2003
> place of humans in evolution. june 2, 2003
> the evolutionary change of our species. september 14, 2002
> human cooperation: biological basis revealed. july 19, 2002
> technology and evolution. paleolithic technology and human evolution. march 13, 2001

imago
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mapping life network evolution

sonic flow
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evolutionary map [stream]
evolutionary map [download]

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friday :: march 3, 2006
   
 
first demonstration of counterfactual computation

By combining quantum computation and quantum interrogation, scientists at the University of Illinois at Urbana-Champaign have found an exotic way of determining an answer to an algorithm – without ever running the algorithm.

Using an optical-based quantum computer, a research team led by physicist Paul Kwiat has presented the first demonstration of “counterfactual computation,” inferring information about an answer, even though the computer did not run.

Quantum computers have the potential for solving certain types of problems much faster than classical computers. Speed and efficiency are gained because quantum bits can be placed in superpositions of one and zero, as opposed to classical bits, which are either one or zero. Moreover, the logic behind the coherent nature of quantum information processing often deviates from intuitive reasoning, leading to some surprising effects.

“It seems absolutely bizarre that counterfactual computation – using information that is counter to what must have actually happened – could find an answer without running the entire quantum computer,” said Kwiat, a John Bardeen Professor of Electrical and Computer Engineering and Physics at Illinois. ”But the nature of quantum interrogation makes this amazing feat possible.”

Sometimes called interaction-free measurement, quantum interrogation is a technique that makes use of wave-particle duality (in this case, of photons) to search a region of space without actually entering that region of space.

Utilizing two coupled optical interferometers, nested within a third, Kwiat’s team succeeded in counterfactually searching a four-element database using Grover’s quantum search algorithm.

“By placing our photon in a quantum superposition of running and not running the search algorithm, we obtained information about the answer even when the photon did not run the search algorithm,” said graduate student Onur Hosten, lead author of the paper. “We also showed theoretically how to obtain the answer without ever running the algorithm, by using a ‘chained Zeno’ effect.”

Through clever use of beam splitters and both constructive and destructive interference, the researchers can put each photon in a superposition of taking two paths. Although a photon can occupy multiple places simultaneously, it can only make an actual appearance at one location. Its presence defines its path, and that can, in a very strange way, negate the need for the search algorithm to run.

“In a sense, it is the possibility that the algorithm could run which prevents the algorithm from running,” Kwiat said. “That is at the heart of quantum interrogation schemes, and to my mind, quantum mechanics doesn’t get any more mysterious than this.”

While the researchers’ optical quantum computer cannot be scaled up, using these kinds of interrogation techniques may make it possible to reduce errors in quantum computing, Kwiat said. “Anything you can do to reduce the errors will make it more likely that eventually you’ll get a large-scale quantum computer.”

In addition to Kwiat and Hosten, co-authors of the Nature paper are graduate students Julio Barreiro, Nicholas Peters and Matthew Rakher (now at the University of California at Santa Barbara). The work was funded by the Disruptive Technologies Office and the National Science Foundation. >from *Quantum computer solves problem, without running*. February 22, 2006

related context
>
quantum interrogation by sean carroll. the recent quantum computing advance, brilliantly explained. february 27, 2006
> qubit link could pave the way for world's most powerful computers. 'first demonstration how qubit rings, pieces of quantum information, can be linked together.' october 17, 2005
> quantum computing in silicon transistors. august 13, 2004
> teleportation milestone: single mechanism for entanglement. february 13, 2002
> 7-qubit quantum computer: first demonstration of shor's factoring algorithm. january 3, 2002
> magnetic semiconductor: spintronics advance. 'in the long term, advances in spintronics may usher in vastly more powerful quantum computing.' november 13, 2001
> 5-qubit quantum computer. august 15, 2000

imago
>
...

sonic flow
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exotic algorithm solution [stream]
exotic algorithm solution [download]

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