Schizophrenia not a single disease but multiple genetically distinct disorders
New research shows that schizophrenia isn’t a single disease but a group of eight genetically distinct disorders, each with its own set of symptoms. The finding could be a first step toward improved diagnosis and treatment for the debilitating psychiatric illness.
The research atWashington University School of Medicine in St. Louis is reported online Sept. 15 in The American Journal of Psychiatry.
About 80 percent of the risk for schizophrenia is known to be inherited, but scientists have struggled to identify specific genes for the condition. Now, in a novel approach analyzing genetic influences on more than 4,000 people with schizophrenia, the research team has identified distinct gene clusters that contribute to eight different classes of schizophrenia.
Scientists Detect Neutrinos from Sun’s Core
The evolution and future of carbonate precipitation in marine invertebrates: Witnessing extinction or documenting resilience in the Anthropocene?
Morphological and phylogenetic analyses suggest that the ability to precipitate carbonates evolved several times in marine invertebrates in the past 600 million years. Over the past decade, there has been a profusion of genomic, transcriptomic, and proteomic analyses of calcifying representatives from three metazoan phyla: Cnidaria, Echinodermata, and Mollusca. Based on this information, we compared proteins intimately associated with precipitated calcium carbonate in these three phyla. Specifically, we used a cluster analysis and gene ontology approach to compare ~1500 proteins, from over 100 studies, extracted from calcium carbonates in stony corals, in bivalve and gastropod mollusks, and in adult and larval sea urchins to identify common motifs and differences. Our analysis suggests that there are few sequence similarities across all three phyla, supporting the independent evolution of biomineralization.
However, there are core sets of conserved motifs in all three phyla we examined. These motifs include acidic proteins that appear to be responsible for the nucleation reaction as well as inhibition; structural and adhesion proteins that determine spatial patterning; and signaling proteins that modify enzymatic activities. Based on this analysis and the fossil record, we propose that biomineralization is an extremely robust and highly controlled process in metazoans that can withstand extremes in pH predicted for the coming century, similar to their persistence through the Paleocene-Eocene Thermal Maximum.- See more at: http://elementascience.org
Labor day reading…
Researchers are transforming light into crystal.
Researchers at Princeton University have begun crystallizing light as part of an effort to answer fundamental questions about the physics of matter.
The researchers are not shining light through crystal – they are transforming light into crystal. As part of an effort to develop exotic materials such as room-temperature superconductors, the researchers have locked together photons, the basic element of light, so that they become fixed in place.
“It’s something that we have never seen before,” said Andrew Houck, an associate professor of electrical engineering and one of the researchers. “This is a new behavior for light.”
The results raise intriguing possibilities for a variety of future materials. But the researchers also intend to use the method to address questions about the fundamental study of matter, a field called condensed matter physics.
“We are interested in exploring – and ultimately controlling and directing – the flow of energy at the atomic level,” said Hakan Türeci, an assistant professor of electrical engineering and a member of the research team. “The goal is to better understand current materials and processes and to evaluate materials that we cannot yet create.”
The team’s findings, reported online on Sept. 8 in the journal Physical Review X, are part of an effort to answer fundamental questions about atomic behavior by creating a device that can simulate the behavior of subatomic particles. Such a tool could be an invaluable method for answering questions about atoms and molecules that are not answerable even with today’s most advanced computers.
In part, that is because current computers operate under the rules of classical mechanics, which is a system that describes the everyday world containing things like bowling balls and planets. But the world of atoms and photons obeys the rules of quantum mechanics, which include a number of strange and very counter-intuitive features. One of these odd properties is called “entanglement” in which multiple particles become linked and can affect each other over long distances.
The difference between the quantum and classical rules limits a standard computer’s ability to efficiently study quantum systems. Because the computer operates under classical rules, it simply cannot grapple with many of the features of the quantum world. Scientists have long believed that a computer based on the rules of quantum mechanics could allow them to crack problems that are currently unsolvable. Such a computer could answer the questions about materials that the Princeton team is pursuing, but building a general-purpose quantum computer has proven to be incredibly difficult and requires further research.
Another approach, which the Princeton team is taking, is to build a system that directly simulates the desired quantum behavior. Although each machine is limited to a single task, it would allow researchers to answer important questions without having to solve some of the more difficult problems involved in creating a general-purpose quantum computer. In a way, it is like answering questions about airplane design by studying a model airplane in a wind tunnel – solving problems with a physical simulation rather than a digital computer.
In addition to answering questions about currently existing material, the device also could allow physicists to explore fundamental questions about the behavior of matter by mimicking materials that only exist in physicists’ imaginations.
To build their machine, the researchers created a structure made of superconducting materials that contains 100 billion atoms engineered to act as a single “artificial atom.” They placed the artificial atom close to a superconducting wire containing photons.
By the rules of quantum mechanics, the photons on the wire inherit some of the properties of the artificial atom – in a sense linking them. Normally photons do not interact with each other, but in this system the researchers are able to create new behavior in which the photons begin to interact in some ways like particles.
“We have used this blending together of the photons and the atom to artificially devise strong interactions among the photons,” said Darius Sadri, a postdoctoral researcher and one of the authors. “These interactions then lead to completely new collective behavior for light – akin to the phases of matter, like liquids and crystals, studied in condensed matter physics.”
Türeci said that scientists have explored the nature of light for centuries; discovering that sometimes light behaves like a wave and other times like a particle. In the lab at Princeton, the researchers have engineered a new behavior.
“Here we set up a situation where light effectively behaves like a particle in the sense that two photons can interact very strongly,” he said. “In one mode of operation, light sloshes back and forth like a liquid; in the other, it freezes.”
The current device is relatively small, with only two sites where an artificial atom is paired with a superconducting wire. But the researchers say that by expanding the device and the number of interactions, they can increase their ability to simulate more complex systems – growing from the simulation of a single molecule to that of an entire material. In the future, the team plans to build devices with hundreds of sites with which they hope to observe exotic phases of light such as superfluids and insulators.
“There is a lot of new physics that can be done even with these small systems,” said James Raftery, a graduate student in electrical engineering and one of the authors. “But as we scale up, we will be able to tackle some really interesting questions.”
Besides Houck, Türeci, Sadri and Raftery, the research team included Sebastian Schmidt, a senior researcher at the Institute for Theoretical Physics at ETH Zurich, Switzerland. Support for the project was provided by: the Eric and Wendy Schmidt Transformative Technology Fund; the National Science Foundation; the David and Lucile Packard Foundation; the U.S. Army Research Office; and the Swiss National Science Foundation.
Read more at http://scienceblog.com/74321/solid-light-compute-previously-unsolvable-problems/#u3MDpsPS2cJjk7Ak.99
Regardless of its cause, sea-level rise is the inevitable, non-debatable consequence of the warming of the oceans and the melting of the planet’s ice sheets. It is a measurable, trackable and relentless reality.Without innovative adaptive capital planning, it will threaten trillions of dollars of the region’s built environment, our future water supply, unique natural resources, agricultural soils and basic economy.
Sound argument for climate adaptation in the Op-ed section of the Miami Herald.
When we learn, we associate a sensory experience either with other stimuli or with a certain type of behaviour. The neurons in the cerebral cortex that transmit the information modify the synaptic connections that they have with the other neurons. According to a generally-accepted model of synaptic plasticity, a neuron that communicates with others of the same kind emits an electrical impulse as well as activating its synapses transiently. This electrical pulse, combined with the signal received from other neurons, acts to stimulate the synapses. How is it that some neurons are caught up in the communication interplay even when they are barely connected? This is the crucial chicken-or-egg puzzle of synaptic plasticity that a team led by Anthony Holtmaat, professor in the Department of Basic Neurosciences in the Faculty of Medicine at UNIGE, is aiming to solve. The results of their research into memory in silent neurons can be found in the latest edition of Nature.
Learning and memory are governed by a mechanism of sustainable synaptic strengthening. When we embark on a learning experience, our brain associates a sensory experience either with other stimuli or with a certain form of behaviour. The neurons in the cerebral cortex responsible for ensuring the transmission of the relevant information, then modify the synaptic connections that they have with other neurons. This is the very arrangement that subsequently enables the brain to optimise the way information is processed when it is met again, as well as predicting its consequences.
Neuroscientists typically induce electrical pulses in the neurons artificially in order to perform research on synaptic mechanisms.
The neuroscientists from UNIGE, however, chose a different approach in their attempt to discover what happens naturally in the neurons when they receive sensory stimuli. They observed the cerebral cortices of mice whose whiskers were repeatedly stimulated mechanically without an artificially-induced electrical pulse. The rodents use their whiskers as a sensor for navigating and interacting; they are, therefore, a key element for perception in mice.
An extremely low signal is enough
By observing these natural stimuli, professor Holtmaat’s team was able to demonstrate that sensory stimulus alone can generate long-term synaptic strengthening without the neuron discharging either an induced or natural electrical pulse. As a result – and contrary to what was previously believed – the synapses will be strengthened even when the neurons involved in a stimulus remain silent.In addition, if the sensory stimulation lasts over time, the synapses become so strong that the neuron in turn is activated and becomes fully engaged in the neural network. Once activated, the neuron can then further strengthen the synapses in a forwards and backwards movement. These findings could solve the brain’s “What came first?” mystery, as they make it possible to examine all the synaptic pathways that contribute to memory, rather than focusing on whether it is the synapsis or the neuron that activates the other.
The entire brain is mobilised
A second discovery lay in store for the researchers. During the same experiment, they were also able to establish that the stimuli that were most effective in strengthening the synapses came from secondary, non-cortical brain regions rather than major cortical pathways (which convey actual sensory information). Accordingly, storing information would simply require the co-activation of several synaptic pathways in the neuron, even if the latter remains silent. These findings may also have important implications both for the way we understand learning mechanisms and for therapeutic possibilities, in particular for rehabilitation following a stroke or in neurodegenerative disorders. As professor Holtmaat explains: “It is possible that sensory stimulation, when combined with another activity (motor activity, for example), works better for strengthening synaptic connections”. The professor concludes: “In the context of therapy, you could combine two different stimuli as a way of enhancing the effectiveness.”
Solar energy that doesn’t block the view
A team of researchers at Michigan State University has developed a new type of solar concentrator that when placed over a window creates solar energy while allowing people to actually see through the window. It is called a transparent luminescent solar concentrator and can be used on buildings, cell phones and any other device that has a clear surface. And, according to Richard Lunt of MSU’s College of Engineering, the key word is “transparent.”
Airglow ripples over Tibet
Why would the sky look like a giant target? Airglow. Following a giant thunderstorm over Bangladesh in late April, giant circular ripples of glowing air appeared over Tibet, China, as pictured above. The unusual pattern is created by atmospheric gravity waves, waves of alternating air pressure that can grow with height as the air thins, in this case about 90 kilometers up. Unlike auroras powered by collisions with energetic charged particles and seen at high latitudes, airglow is due to chemiluminescence, the production of light in a chemical reaction. More typically seen near the horizon, airglow keeps the night sky from ever being completely dark.
Image credit & copyright: Jeff Dai