Thursday, August 25, 2016

big fan of g.o.d. but this strikes me as a very,very bad idea - extra credit to anyone who can tell me why!

 Proceedings of the National Academy of Sciences | Light-driven carbon dioxide reduction to methane by nitrogenase in a photosynthetic bacterium

Significance

One of the most important life-sustaining metabolisms that results from a net reduction reaction is the conversion of nitrogen gas to ammonia by nitrogenase in a process known as nitrogen fixation. A nitrogenase variant has been described that converts carbon dioxide to methane in vitro. Here, we expressed this variant in an engineered strain of the photosynthetic bacterium Rhodopseudomonas palustris and showed biological light-driven methane production. Its ability to reduce carbon dioxide at ambient temperature and pressure with a single enzyme and energy provided by light makes the methane-producing strain of R. palustris an excellent starting point to understand how a biological system can marshal resources to produce an energy-rich hydrocarbon in one enzymatic step.

Thursday, August 4, 2016

explosion of microcephaly in brazil from zika DID NOT OCCUR

Globe and Mail | Brazil opens probe as cases of Zika babies defy predicted patterns
Brazil’s Ministry of Health has launched an investigation into the cluster of babies born with brain defects linked to the Zika virus, after an expected “explosion” of cases across the country did not occur.
The bulk of the cases of congenital Zika syndrome – fetal brain defects that sometimes cause microcephaly, or abnormally small skulls – remain clustered in the northeast region of the country where the phenomenon was first identified last October, the ministry says.
And that has epidemiologists and infectious disease experts asking what is going on: Is it Zika and another virus working together that damages the fetal brains? Is it Zika and an environmental factor? Or something about the women themselves whose fetuses are affected?
The research in Brazil won’t have conclusions for months, but will have implications across the Americas, where the Brazilian experience and the rapid spread of Zika has caused governments to take protective measures and even warn women to delay getting pregnant.
“We can see there is a kind of cluster in [part of] the northeast region with high prevalence and high severity, of miscarriage and congenital malformation that is really severe,” said Fatima Marinho, co-ordinator of epidemiological analysis and information at the ministry.
“But we didn’t find this in other states – even the [adjacent] states didn’t see the same situation as in the epicentre.… We were preparing for an explosion and it didn’t come.
“So we started to think that in this central area maybe more than Zika is causing this intensity and severity.”

how about now...

UC Berkeley | Sprinkling of neural dust opens door to electroceuticals
University of California, Berkeley engineers have built the first dust-sized, wireless sensors that can be implanted in the body, bringing closer the day when a Fitbit-like device could monitor internal nerves, muscles or organs in real time.
Because these batteryless sensors could also be used to stimulate nerves and muscles, the technology also opens the door to “electroceuticals” to treat disorders such as epilepsy or to stimulate the immune system or tamp down inflammation.
The so-called neural dust, which the team implanted in the muscles and peripheral nerves of rats, is unique in that ultrasound is used both to power and read out the measurements. Ultrasound technology is already well-developed for hospital use, and ultrasound vibrations can penetrate nearly anywhere in the body, unlike radio waves, the researchers say.
“I think the long-term prospects for neural dust are not only within nerves and the brain, but much broader,“ said Michel Maharbiz, an associate professor of electrical engineering and computer sciences and one of the study’s two main authors. “Having access to in-body telemetry has never been possible because there has been no way to put something supertiny superdeep. But now I can take a speck of nothing and park it next to a nerve or organ, your GI tract or a muscle, and read out the data.“

how long until this is implantable...

Ars Technica | IBM creates world’s first artificial phase-change neurons
IBM Research in Zurich has created the world's first artificial nanoscale stochastic phase-change neurons. IBM has already created a population of 500 of these artificial neurons and used them to process a signal in a brain-like (neuromorphic) way.
This breakthrough is particularly notable because the phase-change neurons are fashioned out of well-understood materials that can scale down to a few nanometres, and because they are capable of firing at high speed but with low energy requirements. Also important is the neurons' stochasticity—that is, their ability to always produce slightly different, random results, like biological neurons.
Enough fluff—let's talk about how these phase-change neurons are actually constructed. At this point, it might help if you look at the first diagram in the gallery.
...Like a biological neuron, IBM's artificial neuron has inputs (dendrites), a neuronal membrane (lipid bilayer) around the spike generator (soma, nucleus), and an output (axon). There's also a back-propagation link from the spike generator back to the inputs, to reinforce the strength of some input spikes.
The key difference is in the neuronal membrane. In a real neuron, this would be a lipid bilayer, which essentially acts as both a resistor and a capacitor: it resists conductance, but eventually, with enough electricity along the input dendrite, it builds up enough potential that its own spike of electricity is produced—which then flows along the axons to other neurons—and so on and on.
In IBM's neuron, the membrane is replaced with a small square of germanium-antimony-tellurium (GeSbTe or GST). GST, which happens to be the main active ingredient in rewritable optical discs, is a phase-change material. This means it can happily exist in two different phases (in this case crystalline and amorphous), and easily switch between the two, usually by applying heat (by way of laser or electricity). A phase-change material has very different physical properties depending on which phase it's in: in the case of GST, its amorphous phase is an electrical insulator, while the crystalline phase conducts.
With the artificial neurons, the square of GST begins life in its amorphous phase. Then, as spikes arrive from the inputs, the GST slowly begins to crystallise. Eventually, the GST crystallises enough that it becomes conductive—and voilĂ , electricity flows across the membrane and creates a spike. After an arbitrary refractory period (a resting period where something isn't responsive to stimuli), the GST is reset back to its amorphous phase and the process begins again.

Wednesday, August 3, 2016

would you? i just might...

Would you want to alter your future children’s genes to make them smarter, stronger or better-looking? As the state of the science brings prospects like these closer to reality, an international debate has been raging over the ethics of enhancing human capacities with biotechnologies such as so-called smart pills, brain implants and gene editing. This discussion has only intensified in the past year with the advent of the CRISPR-cas9 gene editing tool, which raises the specter of tinkering with our DNA to improve traits like intelligence, athleticism and even moral reasoning.
So are we on the brink of a brave new world of genetically enhanced humanity? Perhaps. And there’s an interesting wrinkle: It’s reasonable to believe that any seismic shift toward genetic enhancement will not be centered in Western countries like the U.S. or the U.K., where many modern technologies are pioneered. Instead, genetic enhancement is more likely to emerge out of China.