‘Vicious cycle’ in brain keeps obesity going
In rat brain cells, obesity blocks the production of a hormone that curbs appetite and inspires calorie burning, according to new research.
The root cause appears to be a breakdown in the protein-processing mechanism of the cells, according to the researchers, who also found that they could intervene to break that cycle by fixing the core protein-processing problem.
Before the study, scientists knew that one mechanism in which obesity perpetuates itself was by causing resistance to leptin, a hormone that signals the brain about the status of fat in the body.
But years ago, senior author Eduardo A. Nillni, professor of medicine at Brown University and a researcher at Rhode Island Hospital, observed that after meals obese rats had a dearth of another key hormone—alpha-MSH—compared to rats of normal weight.
Alpha-MSH has two jobs in parts of the hypothalamus region of the brain. One is to suppress the activity of food-seeking brain cells. The second is to signal other brain cells to produce the hormone TRH, which prompts the thyroid gland to spur calorie-burning activity in the body.
Big data sets create ‘tree of life’ confusion
The genomics revolution has given experts mountains of DNA data to reconstruct the evolution of all living beings, but the vast information has led to contradictory conclusions.
“It has become common for top-notch studies to report genealogies that strongly contradict each other in where certain organisms sprung from, such as the place of sponges on the animal tree or of snails on the tree of mollusks,” says Antonis Rokas, associate professor of biological sciences, at Vanderbilt University.
In a study published online by the journal Nature, Rokas and graduate student Leonidas Salichos analyze the reasons for these differences and propose a suite of novel techniques that can resolve the contradictions and provide greater accuracy in deciphering the deep branches of life’s tree.
“The study by Salichos and Rokas comes at a critical time when scientists are grappling with how best to detect the signature of evolutionary history from a deluge of genetic data. These authors provide intriguing insights into our standard analytical toolbox, and suggest it may be time to abandon some of our most trusted tools when it comes to the analysis of big data sets. This significant work will certainly challenge the community of evolutionary biologists to rethink how best to reconstruct phylogeny,” says Michael F. Whiting, program director of systematics and biodiversity science at the National Science Foundation, which funded the study.
See on Scoop.it - Philosophy everywhere everywhen
You are entitled to believe what you will, but your beliefs must to be subject to criticism and scrutiny just like mine
Here is a true story. A young philosophy lecturer — let us call him Shane — is charged with the task of introducing young minds to the wonders of philosophy. His course, a standard Introduction to Philosophy, contains a section on the philosophy of religion: the usual arguments-for-and-against-the-existence-of-God stuff. One of Shane’s students complains to Shane’s Dean that his cherished religious beliefs are being attacked. ‘I have a right to my beliefs,’ the student claims. Shane’s repeated interrogations of those beliefs amounts to an attack on this right to believe. Shane’s institution is not a particularly enlightened one. The Dean concurs with the student, and instructs Shane to desist in teaching philosophy of religion.
But what exactly does it mean to claim ‘a right to my beliefs’? It often comes up in a religious context, but can arise in others too. Shane could just as easily be teaching Marxist theory to a laissez-faire capitalist student, or imparting evidence for global warming to a global warming sceptic. Whatever the context, the claim of a right to one’s beliefs is a curious one. We might distinguish two different interpretations of this claim. First, there is the evidential one. You have an evidential right to your belief if you can provide appropriate evidence in support of it. I have, in this sense, no right to believe that the moon is made of green cheese because my belief is lacking in any supporting evidence.
Keep on reading..
See on aeonmagazine.com
See on Scoop.it - Cyborg Lives
Forget those Galaxy S4 ads, says Credit Suisse, wearables are “the next big thing.” FORTUNE — Computers one wears, rather than carries in a briefcase, backpack or pocket, are at an “inflection point” — a market poised to explode from $3 billion to $5 billion today to as much as $30 billion to $50 billion in three to five years.
That’s according to a Credit Suisse report snagged Friday by Barron’s Tiernan Ray.
The theory is that smartphones are going to be the hub connecting a proliferation of small, wireless devices that will become increasingly popular as software improves, component prices fall and new business uses emerge.
“Bottom line,” writes Ray, “the authors think wearables are ‘a mega trend’ and that ‘your clients need to care’ because the gizmos may have ‘a significant and pervasive impact on the economy,’ change how we all interact with technology, and may ‘advance [the] Big Data paradigm.’”
Apple (AAPL) is likely to be one of the big winners in the new market, according to the report, along with Broadcom (BRCM), eBay (EBAY), Google (GOOG), Microchip (MCHP), NXP Semiconductor (NXPI) and, among retail stocks, Nike (NKE), Under Armour (AU) and Alliance Data Systems (ADS).
See on tech.fortune.cnn.com
See on Scoop.it - Knowmads, Infocology of the future
Arrays of tree-like nanowires consisting of Si trunks and TiO2 branches facilitate solar water-splitting in a fully integrated artificial photosynthesis system
Lawrence Berkeley National Laboratory (Berkeley Lab) scientists have developed the first fully integrated nanosystem for artificial photosynthesis, in which solar energy is directly converted into chemical fuels.
“Similar to the chloroplasts in green plants that carry out photosynthesis, our artificial photosynthetic system is composed of two semiconductor light absorbers, an interfacial layer for charge transport, and spatially separated co-catalysts,” says Peidong Yang, a chemist with Berkeley Lab’s Materials Sciences Division, who led this research.
“To facilitate solar water- splitting in our system, we synthesized tree-like nanowire heterostructures, consisting of silicon trunks and titanium oxide branches. Visually, arrays of these nanostructures very much resemble an artificial forest.
“In natural photosynthesis, the energy of absorbed sunlight produces energized charge-carriers that execute chemical reactions in separate regions of the chloroplast,” Yang says. “We’ve integrated our nanowire nanoscale heterostructure into a functional system that mimics the integration in chloroplasts and provides a conceptual blueprint for better solar-to-fuel conversion efficiencies in the future.”
See on kurzweilai.net
A new species of philosophers is coming up: I shall venture to baptize them with a name that is not free of danger. As I unriddle them, insofar as they allow themselves to be unriddled, for it belongs to their nature to want to remain riddles; these philosophers of the future may have a right, it might also be a wrong, to be called “tempters.” This name itself is in the end a mere attempt and, if you will, a temptation.
Are these coming philosophers new friends of “truth”? That is probable enough, for all philosophers so far have loved their truths. But they will certainly not be dogmatists. It must offend their pride, also their taste, if their truth is supposed to be a truth for every man—which has so far been the secret wish and hidden meaning of all dogmatic aspirations. “My judgment is my judgment: no one else is easily entitled to it”—that is what such a philosopher of the future may perhaps say of himself. One must shed the bad taste of wanting to agree with many. “Good” is no longer good when one’s neighbor mouths it. And how should there be a “common good”! The term contradicts itself: whatever can be common always has little value. In the end it must be as it is and always has been: great things remain for the great, abysses for the profound, nuances and shudders for the refined, and, in brief, all that is rare for the rare.”
Friedrich Nietzsche, Beyond Good and Evil (via ludimagister)