WithÂ optogenetics, a technique that uses beams of light to control the activity of particular cells, researchers have already flicked on clusters of neurons that trigger aggressive behavior and ramped up insulin production in mice.Â Now, scientists are applying the technique to the heart, working towards a cardiac pacemaker driven by light, Courtney Humphries reports in Technology Review.
First, the researchers genetically modified animal cells so they responded to light. Then, they took advantage of heart muscle cells’ natural tendency to pair up, and coupled the modified cells to heart muscle cells. Pulses of light triggered a “heartbeat” in both types of cells—suggesting that a small cluster of modified cells might be enough to keep pace for the whole heart.Â Light-powered pacemakers are a long way from ready for the clinic, but the approach could use less power than artificial pacemakers, and give doctors more control over exactly where and when the pacemaker kicks in.
Read more at Technology Review.
Image courtesy of Heikenwaelder / Wikimedia Commons
In the justice system, a confession is often treated as proof of guilt—and yet, a surprising number of people confess to crimes they didn’t commit. In its latest issue, the Economist reviews recent research showing just how frequently innocent people ‘fess up, and what factors lead them to do it.
When an experimenter falsely accused subjects of crashing a computer, 25% of them confessed even though they’d done nothing wrong, one study found. If the accusation was corroborated by a (lying) eyewitness, that number jumped to 80%. In another study, participants falsely accused of cheating on a task were told that authority figures were processing evidence that could prove their guilt—in this case, a tape. Half the people confessed, even though they must have known the tape recorded their actual, innocent behavior. This is particularly worrying because police often use this same tactic when waiting to get DNA or fingerprint results.
While the situations—research subject vs. crime suspect—are of course quite different, the parallels are enough to give one pause.
Read the full story at the Economist.
Image courtesy of Pearson Scott Foresman / Wikimedia Commons
Source: Why Do the Innocent Confess?
Scientists have now sequenced the genome of the Atlantic cod, revealing something unusual: the cod is missing an important component of the adaptive immune system found in almost all jawed vertebrates. In particular, when the researchers compared the cod’s genome to that of the stickleback (a closely related fish that has already been sequenced), they saw that the Atlantic cod does not have genes that code for the proteins MHC II, CD4, and invariant chain, all of which work together to help the body recognize and fight off invading bacteria and parasites.
But the missing genes is not a death sentence for the cod. To make up for the lack of MHC II, the cod has ten times more genes for MHC Iâ€”another component of the immune systemâ€”than other vertebrates. The researchers think that MHC I system may be picking up some of the functions of MHC II, according to ScienceNOW. The researchers also noticed that cod have an increased amount of Toll-like receptors, which are part of the innate immune system.
The find could lead to improved vaccines for farmed cod, and it may have important consequences for the treatment of human diseases. “Maybe we can regulate the human immune system differently and maybe that could be treatment against certain diseases, multiple sclerosis for example,” lead researcher Kjetill Jakobsen told the Guardian.
Image courtesy of Hans-Petter Fjeld / Wikimedia Commons
Researchers at Wake Forest University in North Carolina have now learned that Nazca boobies perpetuate a “cycle of violence”: bullied chicks tend to become bullies and pass on the pain. When parent birds leave their nests to eat, baby boobies are often visited by sexually and physically abusive non-breeding adults; the chicks, when grown, are more likely to abuse unrelated chicks. “The link we found indicates that nestling experience, and not genetics, influences adult behaviour,” lead researcher David Anderson told BBC.
This behavior may have to do with hormone levels in the brain, according to another recent study out of Wake Forest University. Researchers found that concentrations of the stress hormone corticosterone in Nazca booby chicks increased five-fold during bullying events. The team believes that the spike in hormonal levels could have a long-term effect on the boobies’ brains, causing aggressive behavior later in life.
Image courtesy of Marc Figueras / Wikimedia Commons
Current drugs for conditions from depression to Parkinson’s work by changing levels of chemicals in the brain—an imprecise method that can have a wide range of unintended effects. But a new study suggests it could be possible to make drugs that work by turning off genes instead, getting at, for instance, a specific receptor in a particular part of the brain.
The researchers attached an anti-depressant, setraline, to a bit of what’s called small interfering RNA. They found that when mice were given the combo nasally, it shut off a particular serotonin receptor thought to be involved in depression in just the region of the brain they were aiming for, and nowhere else. On his blog, Neuroskeptic points out that it’s not clear when, or if, the drug will be ready for humans—but wow, is that an exciting idea:
The mind boggles at the potential. If you could selectively alter the gene expression of selective neurons, you could do things to the brain that are currently impossible. Existing drugs hit the whole brain, yet there are many reasons why you’d prefer to only affect certain areas. And editing gene expression would allow much more detailed control over those cells than is currently possible.
You can read more about the study, and its implications, at Neuroskeptic.
Image courtesy of Shorelander / Wikimedia Commons
Dora Siliya, the Minister of Education for the African country of Zambia, and the spokesperson for the ruling Movement for Multiparty Democracy, has turned to her Facebook page to make national policy announcements.
This isn’t the first time an African leader has used Facebook to reach out to his or her citizens. Nigeria’s interim president, Goodluck Jonathan, used the social networking service to announce his run for the presidency.
Palestinian prime minister, Salam Fayyad, has also availed himself of the outreach capacities of the popular site, using his account to crowdsource a new cabinet.
Siliya, a graduate of the University of Zambia and of Cambridge University in the U.K, posts mostly about educational issues, soliciting ideas and opinions from her people about large issues and about specific decisions. One such decision was that to increase access the country’s safety-net schooling program, the APU. The announcement inspired 50 comments on that post alone, split between critics and boosters of the decision.
The minister is fast approaching the 5,000 friend cut-off limit that Facebook enforces. (As of this writing he’s within 42 friends of reaching that point.) Given the average circulation for the country’s main newspapers of about 10,000, this is a large reach.
The role that social media is playing in opening channels for conversation between public servants and the public they serve is undeniable, and Facebook, being the largest social media network, is taking a lead. In many ways, that is heartening. But given Facebook’s checkered history regarding user privacy, and its persistent opposition to anonymity, the trend should not be welcomed uncritically.
According to a press release from the International Telecommunications Union, a new undersea data cable connected to Cuba this week will increase the amount of the country’s data and video transmission speed 3,000-fold when it becomes operation this summer.
The ALBA-1 cable arrived in Siboney on February 9th, linking the eastern Cuban town to the cable’s start-point in the Venezuelan port city of La Guaira. The second part of the project will lead from Cuba to Ochos Rios in Jamaica.
The Prestige of the Internet
The Venezuela-Cuba joint project has been advertised as a triumph against the United States embargo of the island nation. Venezuela’s Gran Caribe and Cuba’s Transbit hired a Chinese subsidiary of the French company Alcatel-Lucent to lay the cable at a cost of $70 million. It took 19 days for the specialized cable-laying ship, Île de Batz to make the journey from Venezuela.
The project is an indication of how important the Internet is, even to countries whose relationship to communications is antagonistic. Currently, virtually no private Cuban citizens can secure an Internet connection. To blog, Cuba’s small blogger community must copy their posts onto a thumb-drive and sneak into a dollar-only hotel to post, or to email the post to compatriots outside the country.
According to a leaked diplomatic cable, the Cuban government is more afraid of this small but powerful group of bloggers than it is of its entire old-style dissident population.
Nevertheless, according to the press release:
“Cuban officials say the country’s priority will be to build more public telecentres and improve Internet access at schools, hospitals and scientific institutions.”
eldavojohn writes “The FBI got in contact with Wikipedia’s San Francisco office to inform them they were violating the law in regards to ‘unauthorized production’ of this seal. The FBI quoted the law as saying, ‘Whoever possesses any insignia… or any colorable imitation thereof… shall be fined… or imprisoned… or both.’ Wikipedia refused to take the image down and stated that the FBI was misquoting the law. The FBI claims that this production of this image is ‘particularly problematic, because it facilitates both deliberate and unwitting violations of restrictions by Wikipedia users.’ Wikipedia’s lawyer, Mike Godwin (please omit certain jokes), contacted the FBI and asserted, ‘We are compelled as a matter of law and principle to deny your demand for removal of the FBI Seal from Wikipedia and Wikimedia Commons,’ adding that the firm was ‘prepared to argue our view in court.’ Wikipedia appears to be holding their ground; we shall see if the FBI comes to their senses or proceeds with litigation.”
Contridictory stories are circulating after Fox News’s pursuing of Wikimedia Foundation for hosting pornography reportedly resulted in Jimmy Wales personally removing some pornographic material from its servers, then giving up his special editing privileges under pressure. Fox News reported that Wikimedia is “in chaos“; this report was picked up by VentureBeat and others. Wales denies that there is any chaos (any more than usual that is) at Wikimedia. The Fox News report apparently relied on a single unnamed source, and Wales said “They don’t even bother to contact me before publishing nonsense.” The background: on April 27 Fox News published an exclusive report about porn on Wikimedia servers, then followed up by contacting organizations that had donated to Wikimedia to ask them what they thought about it. In the aftermath, Wales took a position in support of purging porn from Wikimedia Commons. This all started when estranged Wikipedia co-founder Larry Sanger contacted the FBI with an allegation of child porn on Wikipedia.