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Plastic shopping bags can be converted to fine diesel fuel

Plastic shopping bags can be converted to fine diesel fuel | Amazing Science | Scoop.it

Plastic shopping bags, an abundant source of litter on land and at sea, can be converted into diesel, natural gas and other useful petroleum products, researchers report. The conversion produces significantly more energy than it requires and results in transportation fuels -- diesel, for example -- that can be blended with existing ultra-low-sulfur diesels and biodiesels.


The conversion produces significantly more energy than it requires and results in transportation fuels -- diesel, for example -- that can be blended with existing ultra-low-sulfur diesels and biodiesels. Other products, such as natural gas, naphtha (a solvent), gasoline, waxes and lubricating oils such as engine oil and hydraulic oil also can be obtained from shopping bags.


A report of the new study appears in the journal Fuel Processing TechnologyThere are other advantages to the approach, which involves heating the bags in an oxygen-free chamber, a process called pyrolysis, said Brajendra Kumar Sharma, a senior research scientist at the Illinois Sustainable Technology Center who led the research. The ISTC is a division of the Prairie Research Institute at the University of Illinois.


"You can get only 50 to 55 percent fuel from the distillation of petroleum crude oil," Sharma said. "But since this plastic is made from petroleum in the first place, we can recover almost 80 percent fuel from it through distillation."


Americans throw away about 100 billion plastic shopping bags each year, according to the Worldwatch Institute. The U.S. Environmental Protection Agency reports that only about 13 percent are recycled. The rest of the bags end up in landfills or escape to the wild, blowing across the landscape and entering waterways.


Plastic bags make up a sizeable portion of the plastic debris in giant ocean garbage patches that are killing wildlife and littering beaches. Plastic bags "have been detected as far north and south as the poles," the researchers wrote.


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Face-To-Face: Crude Mugshots built from DNA data alone

Face-To-Face: Crude Mugshots built from DNA data alone | Amazing Science | Scoop.it
Computer program crudely predicts a facial structure from genetic variations.


Researchers have now shown how 24 gene variants can be used to construct crude models of facial structure. Thus, leaving a hair at a crime scene could one day be as damning as leaving a photograph of your face. Researchers have developed a computer program that can create a crude three-dimensional (3D) model of a face from a DNA sample.


Using genes to predict eye and hair color is relatively easy. But the complex structure of the face makes it more valuable as a forensic tool — and more difficult to connect to genetic variation, says anthropologist Mark Shriver of Pennsylvania State University in University Park, who led the work, published today in PLOS Genetics1.


Shriver and his colleagues took high-resolution images of the faces of 592 people of mixed European and West African ancestry living in the United States, Brazil and Cape Verde. They used these images to create 3D models, laying a grid of more than 7,000 data points on the surface of the digital face and determining by how much particular points on a given face varied from the average: whether the nose was flatter, for instance, or the cheekbones wider. They had volunteers rate the faces on a scale of masculinity and femininity, as well as on perceived ethnicity.


Next, the authors compared the volunteers’ genomes to identify points at which the DNA differed by a single base, called a single nucleotide polymorphism (SNP). To narrow down the search, they focused on genes thought to be involved in facial development, such as those that shape the head in early embryonic development, and those that are mutated in disorders associated with features such as cleft palate. Then, taking into account the person’s sex and ancestry, they calculated the statistical likelihood that a given SNP was involved in determining a particular facial feature.


This pinpointed 24 SNPs across 20 genes that were significantly associated with facial shape. A computer program the team developed using the data can turn a DNA sequence from an unknown individual into a predictive 3D facial model (see 'Face to face'). Shriver says that the group is now trying to integrate more people and genes, and look at additional traits, such as hair texture and sex-specific differences.

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By screening over 1,000 different compounds, scientists have identified one that "vacuolizes" glioblastoma cells

By screening over 1,000 different compounds, scientists have identified one that "vacuolizes" glioblastoma cells | Amazing Science | Scoop.it

Currently, only 5 percent of patients with GBM survive longer than three years, and the average life expectancy of a patient is 15 months. Even when aggressive therapies are implemented, "GBM is essentially incurable," the researchers wrote in the study. So identifying vulnerabilities in this cancer's cells is an essential step in the development of new drug therapies.

The compound that eventually caught researchers' attention is called "Vacquinol-1," and although it certainly did kill cancer cells, it did so in a way that was unlike anything else they'd seen.

The molecule works by shutting off the cells' ability to control what gets in and out of their walls. This causes bag-like vessels filled with water and other materials, called vacuoles, to accumulate in the cells. Under these conditions, the cells eventually reach capacity and explode. But what's truly remarkable is that the noncancerous cell types that surround the cancer cells remain intact, so the treatment is actually GBM-specific.


Treatments that work in a petri dish, however, don't always work in the living. So the scientists set up a second test involving mice, and fed the compound to a group of mice with brain tumors for five days. The treatment did not cause any severe side effects. Instead, the tumors stopped growing and eventually disappeared. Moreover, six of the eight mice who received the treatment survived for 80 days following the feeding period — about 50 days longer than the mice who weren't given the drug.


Ravi Bellamkonda, a neuroscientist at the Georgia Institute of Technology who did not participate in the study, wrote in an email to The Verge that he was intrigued by the idea of being able to induce death in glioma cells specifically. "They have shown very exciting results."


But Bellamkonda also expressed some reservations about the approach, because the study's researchers had to administer what he calls "relatively high levels of the drug" to make it work. Furthermore, it's unclear if the concentrations of the drug need to be higher elsewhere in the body to reach the cancer cells — which might induce side-effects that would have been difficult to identify in the study. "This said, enhancing survival by several fold in aggressive tumor models is encouraging," he wrote. "I'd love to see more studies."


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Nanoscale graphene origami cages set world record for densest hydrogen storage

Nanoscale graphene origami cages set world record for densest hydrogen storage | Amazing Science | Scoop.it

The U.S. Department of Energy is searching for ways to make storing energy with hydrogen a practical possibility, and they set up some goals for onboard automotive hydrogen storage systems with a driving range of 300 miles or more: the Department had hoped that by 2017, a research team could pack in 5.5 percent hydrogen by weight, and that by 2020, it could be stretched to 7.5 percent. Li’s team has already crossed that threshold, with a hydrogen storage density of 9.5 percent hydrogen by weight.  The team has also demonstrated the potential to reach an even higher density, a future research goal.


“Just like paper origami, which can make complicated 3-D structures from 2-D paper, graphene origami allows us to design and fabricate carbon nanostructures that are not naturally existing but have desirable properties,” said Li, an Associate Professor of Mechanical Engineering, a member of the Maryland NanoCenter and the University of Maryland Energy Research Center (UMERC), and a Keystone professor in the A. James Clark School of Engineering. Forming a graphene nanocage: (a) Patterned graphene is suitably hydrogenated (by bonding hydrogen atoms to the carbon atoms of planar graphene, thus warping it) and then folded (b-f) into a nanocage via electric-field assistance. (Credit: Shuze Zhu and Teng Li/ACS Nano“In this paper, we show that graphene nanocages can be used for hydrogen storage with extraordinary capacity, holding the promise to exceed the year 2020 goal of the U.S. Department of Energy on hydrogen storage,” Li explained to KurzweilAI in an email interview.


“Paper origami has existed for more than a millennium. Such a concept has been explored to enable the formation of complicated 3D structures from 2D building blocks in recent years, such as micro-robots and actuators. In these developments, the building block materials are still bulk materials, with a final resulting 3D structure of size on the order of millimeters. “The graphene origami we demonstrate in this paper uses the thinnest yet strongest materials ever made (one atom thick), leading to a nanocage on the order of several nanometers. Another unique feature of [Hydrogenation-assisted graphene origami] HAGO that does not exist in conventional origami is that programmable opening and closing of HAGO-enabled nanostructures can be controlled via an external electric field.

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Anesthesia may have lingering side effects on the brain, even years after an operation

Anesthesia may have lingering side effects on the brain, even years after an operation | Amazing Science | Scoop.it

Two and a half years ago Susan Baker spent three hours under general anesthesia as surgeons fused several vertebrae in her spine. Everything went smoothly, and for the first six hours after her operation, Baker, then an 81-year-old professor at the Johns Hopkins Bloomberg School of Public Health, was recovering well. That night, however, she hallucinated a fire raging through the hospital toward her room. Petrified, she repeatedly buzzed the nurses' station, pleading for help. The next day she was back to her usual self. “It was the most terrifying experience I have ever had,” she says.


Baker's waking nightmare was a symptom of postoperative delirium, a state of serious confusion and memory loss that sometimes follows anesthesia.


Anesthesia comes in three main types. Local anesthesia, the mildest form, merely numbs a very small area, such as a single tooth. Regional anesthesia desensitizes a large section of someone's body by injecting drugs into the spine that block nerve signals to the brain. Often a patient getting regional anesthesia also takes a relatively small dose of a powerful sedative drug, such as propofol—not enough to put them under but enough to alter brain activity in a way that makes the person less aware and responsive.


General anesthesia relies on a cocktail of drugs that renders patients completely unconscious, prevents them from moving and blocks any memories of the surgery. Although anesthetic drugs have been around since 1846, many questions remain as to how exactly they work. To date, the strongest evidence suggests that the drugs are effective in part because they bind to and incapacitate several different proteins on the surface of neurons that are essential for regulating sleep, attention, learning and memory. In addition, it seems that interrupting the usual activity of neurons may disrupt communication between far-flung regions of the brain, which somehow triggers unconsciousness.


When postoperative delirium was first recognized, researchers wondered whether certain anesthetic drugs—but not others—deserved the blame. Yet studies comparing specific drugs and rates of delirium in patients after surgery have always been scant and inconclusive. “No particular anesthetic has been exonerated in patients,” says Roderic G. Eckenhoff, a professor of anesthesiology at the University of Pennsylvania. But “we can't say yet that there is an anesthetic that patients should not get.”

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CODE_n: Data Visualizations in Grande Scale Shown at CeBit 2014

CODE_n: Data Visualizations in Grande Scale Shown at CeBit 2014 | Amazing Science | Scoop.it

I guess that CODE_n [http://kramweisshaar.com], developed by design agency Kram/Weisshaar, is best appreciated when perceived in the flesh, that is at the Hannover Fairgrounds during CeBit 2014 in Hannover, Germany.


CODE_n consists of more than 3.000 square meters (approx. 33,000 ft2) of ink-jet printed textile membranes, stretching more than 260 meters of floor-to-ceiling tera-pixel graphics. The 12.5 terapixel, 90-meter long wall-like canopy titled "Retrospective Trending", shows over 400 lexical frequency timelines ranging from the years 1800 to 2008, each generated using Google's Ngram tool. The hundreds of search terms relate to ethnographic themes of politics, economics, engineering, science, technology, mathematics, and philosophy, resulting in the output of historical trajectories of word usage over time.


The 6.2 terapixel "Hydrosphere Hyperwall" is a visualization of the global ocean as dynamic pathways, polychrome swathes of sea climate, data-collecting swarms of mini robots and sea animals, as well as plumes of narrow current systems. NASA's ECCO2 maps were interwoven with directional arrows that specify wind direction and data vectors that represent buoys, cargo floats, research ships, wave gliders, sea creatures and research stations.


Finally, the 6.6 terapixel "Human Connectome" is a morphological map of the human brain. Consisting of several million multi-coloured fibre bundles and white matter tracts that were captured by diffusion-MRIs, the structural descriptions of the human mind were generated at 40 times the scale of the human body. The 3D map of human neural connections visualizes brain dynamics on an ultra-macro scale as well as the infinitesimal cell-scale.

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NASA Study Finds That Amazon Rainforest Inhales More Carbon than It Emits

NASA Study Finds That Amazon Rainforest Inhales More Carbon than It Emits | Amazing Science | Scoop.it

A new NASA-led study seven years in the making has confirmed that natural forests in the Amazon remove more carbon dioxide from the atmosphere than they emit, therefore reducing global warming. This finding resolves a long-standing debate about a key component of the overall carbon balance of the Amazon basin.


The Amazon's carbon balance is a matter of life and death: living trees take carbon dioxide out of the air as they grow, and dead trees put the greenhouse gas back into the air as they decompose. The new study, published in Nature Communications on March 18, is the first to measure tree deaths caused by natural processes throughout the Amazon forest, even in remote areas where no data have been collected at ground level.


Fernando Espírito-Santo of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., lead author of the study, created new techniques to analyze satellite and other data. He found that each year, dead Amazonian trees emit an estimated 1.9 billion tons (1.7 billion metric tons) of carbon to the atmosphere. To compare this with Amazon carbon absorption, the researchers used censuses of forest growth and different modeling scenarios that accounted for uncertainties. In every scenario, carbon absorption by living trees outweighed emissions from the dead ones, indicating that the prevailing effect in natural forests of the Amazon is absorption.


Until now, scientists had only been able to estimate the Amazon's carbon balance from limited observations in small forest areas called plots. On these plots, the forest removes more carbon than it emits, but the scientific community has been vigorously debating how well the plots represent all the natural processes in the huge Amazon region. That debate began with the discovery in the 1990s that large areas of the forest can be killed off by intense storms in events called blowdowns.


Espírito-Santo said that the idea for the study arose from a 2006 workshop where scientists from several nations came together to identify NASA satellite instruments that might help them better understand the carbon cycle of the Amazon. In the years since then, he worked with 21 coauthors in five nations to measure the carbon impacts of tree deaths in the Amazon from all natural causes -- from large-area blowdowns to single trees that died of old age. He used airborne lidar data, satellite images, and a 10-year set of plot measurements collected by the University of Leeds, England, under the leadership of Emanuel Gloor and Oliver Phillips. He estimates that he himself spent a year-and-a-half doing fieldwork in the Amazon.


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Scientists finally solve the mystery of New Zealand's Moas disappearanc

Scientists finally solve the mystery of  New Zealand's Moas disappearanc | Amazing Science | Scoop.it

Scientists have long argued about what caused the extinction of many species of megafauna—giant animals including mammoths, mastodons, and moas—beginning between 9000 and 13,000 years ago, when humans began to spread around the world. Often, the animals disappeared shortly after humans arrived in their habitats, leading some researchers to suggest that we exterminated them by overhunting. But other scientists have pointed to natural causes, including volcanic eruptions, disease, and climate change at the end of last Ice Age, as the key reasons for these species’ demise. The moas present a particularly interesting case, researchers say, because they were the last of the giant species to vanish, and they did so recently, when a changing climate was no longer a factor. But did other natural causes set them on a path to oblivion, as some scientists proposed in a recent paper?


Morten Allentoft, an evolutionary biologist at the University of Copenhagen, doubted this hypothesis. Archaeologists know that the Polynesians who first settled New Zealand ate moas of all ages, as well as the birds’ eggs. With moa species ranging in size from 12 to 250 kilograms, the birds—which had never seen a terrestrial mammal before people arrived—offered sizable meals. “You see heaps and heaps of the birds’ bones in archaeological sites,” Allentoft says. “If you hunt animals at all their life stages, they will never have a chance.”


Using ancient DNA from 281 individual moas from four different species, including Dinornis robustus (at 2 meters, the tallest moa, able to reach foliage 3.6 meters above the ground), and radiocarbon dating, Allentoft and his colleagues set out to determine the moas’ genetic and population history over the last 4000 years. The moa bones were collected from five fossil sites on New Zealand’s South Island, and ranged in age from 12,966 to 602 years old. The researchers analyzed mitochondrial and nuclear DNA from the bones and used it to examine the genetic diversity of the four species.


Usually, extinction events can be seen in a species’ genetic history; as the animals’ numbers dwindle, they lose their genetic diversity. But the team’s analysis failed to find any sign that the moas’ populations were on the verge of collapse. In fact, the scientists report that the opposite was true: The birds’ numbers were stable during the 4000 years prior to their extinction, they report online today in the Proceedings of the National Academy of Sciences. Populations of D. robustus even appear to have been slowly increasing when the Polynesians arrived. No more than 200 years later, the birds had vanished. “There is no trace of” their pending extinction in their genes, Allentoft says. “The moa are there, and then they are gone.”


The paper presents an “impressive amount of evidence” that humans alone drove the moa extinct, says Trevor Worthy, an evolutionary biologist and moa expert at Flinders University in Adelaide, Australia, who was not involved with the research. “The inescapable conclusion is these birds were not senescent, not in the old age of their lineage and about to exit from the world. Rather they were robust, healthy populations when humans encountered and terminated them.” Still, he doubts even Allentoft’s team’s “robust data set” will settle the debate about the role people played in the birds’ extinction, simply because “some have a belief that humans would not have” done such a thing.

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Deborah Verran's comment, March 18, 2014 4:16 AM
They had the biggest "drumsticks" ever seen....hence the attraction to the humans who settled in New Zealand!
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Spectacular cosmic discovery hailed: Gravitational waves put twist pattern on CMB

Spectacular cosmic discovery hailed: Gravitational waves put twist pattern on CMB | Amazing Science | Scoop.it

Scientists say they have extraordinary new evidence to support a Big Bang Theory for the origin of the Universe. Researchers believe they have found the signal left in the sky by the super-rapid expansion of space that must have occurred just fractions of a second after everything came into being.


It takes the form of a distinctive twist in the oldest light detectable with telescopes. The work will be scrutinised carefully, but already there is talk of a Nobel. "This is spectacular," commented Prof Marc Kamionkowski, from Johns Hopkins University.


"I've seen the research; the arguments are persuasive, and the scientists involved are among the most careful and conservative people I know," he said.


The breakthrough was announced by an American team working on a project known as BICEP2This has been using a telescope at the South Pole to make detailed observations of a small patch of sky.


The aim has been to try to find a residual marker for "inflation" - the idea that the cosmos experienced an exponential growth spurt in its first trillionth, of a trillionth of a trillionth of a second.


Theory holds that this would have taken the infant Universe from something unimaginably small to something about the size of a marble. Space has continued to expand for the nearly 14 billion years since.


Inflation was first proposed in the early 1980s to explain some aspects of Big Bang Theory that appeared to not quite add up, such as why deep space looks broadly the same on all sides of the sky. The contention was that a very rapid expansion early on could have smoothed out any unevenness.


But inflation came with a very specific prediction - that it would be associated with waves of gravitational energy, and that these ripples in the fabric of space would leave an indelible mark on the oldest light in the sky - the famous Cosmic Microwave Background.


The BICEP2 team says it has now identified that signal. Scientists call it B-mode polarisation. It is a characteristic twist in the directional properties of the CMB. Only the gravitational waves moving through the Universe in its inflationary phase could have produced such a marker. It is a true "smoking gun".


"Detecting this signal is one of the most important goals in cosmology today. A lot of work by a lot of people has led up to this point," said Prof John Kovac of the Harvard-Smithsonian Center for Astrophysics and a leader of the BICEP2 collaboration.


The signal is reported to be quite a bit stronger than many scientists had dared hope. This simplifies matters, say experts. It means the more exotic models for how inflation worked are no longer tenable.


The results also constrain the energies involved - at 10,000 trillion gigaelectronvolts. This is consistent with ideas for what is termed Grand Unified Theory, the realm where particle physicists believe three of the four fundamental forces in nature can be tied together.

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Dark matter looks more and more likely after new gamma-ray analysis

Dark matter looks more and more likely after new gamma-ray analysis | Amazing Science | Scoop.it
Scientists describe as 'extremely interesting' new analysis that makes case for gamma rays tracing back to Wimp particles


Not long after the Fermi Gamma-ray SpaceTelescope took to the sky in 2008, astrophysicists noticed that it was picking up a steady rain of gamma rays pouring outward from the center of the Milky Way galaxy.


This high-energy radiation was consistent with the detritus of annihilating dark matter, the unidentified particles that constitute 84% of the matter in the universe and that fizzle upon contact with each other, spewing other particles as they go. If the gamma rays did in fact come from dark matter, they would reveal its identity, resolving one of the biggest mysteries in physics. But some argued that the gamma rays could have originated from another source.


Now a new analysis of the signal claims to rule out all other plausible explanations and makes the case that the gamma rays trace back to a type of particle that has long been considered the leading dark matter candidate – a weakly interacting massive particle, or Wimp. Meanwhile, a more tentative X-ray signal reported in two other new studies suggests the existence of yet another kind of dark matter particle called a sterile neutrino.


In the new gamma-ray analysis, which appeared February 27 on the scientific preprint site arXiv.org, Dan Hooper and his collaborators used more than five years' worth of the cleanest Fermi data to generate a high-resolution map of the gamma-ray excess extending from the center of the galaxy outward at least 10 angular degrees, or 5,000 light-years, in all directions.


"The results are extremely interesting," said Kevork Abazajian, an associate professor of physics and astronomy at the University of California, Irvine. "The most remarkable part of the analysis is that the signal follows the shape of the dark matter profile out to 10 degrees," he said, explaining that it would be "very difficult to impossible" for other sources to mimic this predicted dark matter distribution over such a broad range.


The findings do not constitute a discovery of dark matter, the scientists said, but they prepare the way for an upcoming test described by many researchers as a "smoking gun": If the gamma-ray excess comes from annihilating Wimps, and not conventional astrophysical objects, then the signal will also be seen emanating from dwarf galaxies that orbit the Milky Way – diffuse objects that are rich in dark matter but not in other high-energy photon sources such as pulsars, rotating neutron stars that have been floated as alternative explanations for the excess.

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Eli Levine's curator insight, March 16, 2014 1:50 PM

The more we know about this place we call "the universe" the more likely we'll be able to understand ourselves and to put our minds to ease about a great many of our pressing questions.

 

The more we know about this place, the more likely it will be that we're able to alleviate suffering, misery and, hopefully, bring a greater quality of life and sense of peace to all of our minds.

 

Assuming that each of our particular minds are willing and able to accept the truths of this world in the first place.

 

Think about it.

malik matwi's comment, December 13, 2015 3:18 PM
neither dark matter nor energy http://iiste.org/Journals/index.php/APTA/article/view/26837
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Two-dimensional crystalline structure assembled from outer shells of a virus

Two-dimensional crystalline structure assembled from outer shells of a virus | Amazing Science | Scoop.it

From steel beams to plastic Lego bricks, building blocks come in many materials and all sizes. Today, science has opened the way to manufacturing at the nanoscale with biological materials. Potential applications range from medicine to optoelectronic devices.


In a paper published in Soft Matter, September 2013, scientists announced their discovery of a two-dimensional crystalline structure assembled from the outer shells of a virus. A virus consists of a protein shell protecting an interior consisting of either DNA or RNA.


"We are excited about the potential of virus-like particles as building blocks for creating new nanostructures," said the paper's lead author, Masafumi Fukuto, a physicist in the Condensed Matter Physics and Materials Science Department at Brookhaven National Laboratory. "For the particular virus that we studied, we discovered two new forms of 2D crystals that are distinct from previously observed hexagonal and square crystals."


The team used as their model system the turnip yellow mosaic virus (TYMV), which infects cruciferous vegetables like cabbages, cauliflower and broccoli. TYMV's protein shell resembles a soccer ball, which is characterized by a set of many axes with rotational symmetry, including two-fold axes between a pair of hexagons, three-fold axes through the center of hexagons, and five-fold axes through pentagons. This is known as icosahedral symmetry: all 20 hexagons are identical and all 12 pentagons are identical.


Fukuto described their work as new because it focuses on the structural diversity in the 2D arrays that arise from the constituent particle's high symmetry and regular shape. "Viruses have been used in previous studies of self-assembly, but in nearly all of those studies, the virus particles were treated as spheres and the ordered 2D arrays observed were hexagonal lattices," he said. "Second, this work is unique for demonstrating a rational approach to 2D crystallization that is based on controlling the interactions of virus particles, which occur at the surface of an aqueous solution where the 2D arrays are formed."

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Medical microrobots to deliver drugs on demand

Medical microrobots to deliver drugs on demand | Amazing Science | Scoop.it

Advances in micro- and nanoscale engineering in the medical field have led to the development of various robotic designs that one day will allow a new level of minimally invasive medicine. These micro- and nanorobots will be able to reach a targeted area, provide treatments and therapies for a desired duration, measure the effects and, at the conclusion of the treatment, be removed or degrade without causing adverse effects. Ideally, all these tasks would be automated but they could also be performed under the direct supervision and control of an external user.Several approaches have been explored for the wireless actuation of microrobots. Among these, magnetic fields have been the most widely employed strategy for propulsion because they do not require special environmental properties such as conductivity or transparency (for instance: "Artificial nano swimmers", with a video that shows the controlled motions of particles in a magnetic field).


This approach allows for the precise manipulation of magnetic objects toward specific locations, and magnetic fields are biocompatible even at relatively high field strengths (MRI).In a new work, a team of researchers from ETH Zurich and Harvard University (David Mooney's lab) demonstrate that additional intelligence – including sensing and actuation – can be instantiated in these microrobots by selecting appropriate materials and methods for the fabrication process.


"Our work combines the design and fabrication of near infrared light (NIR) responsive hydrogel capsules and biocompatible magnetic microgels with a magnetic manipulation system to perform targeted drug and cell delivery tasks, Dr." Mahmut Selman Sakar, a research scientist in Bradley Nelson's Institute of Robotics and Intelligent Systems at ETH Zurich, tells Nanowerk.Reporting their results in the November 4, 2013 online edition of Advanced Materials ("An Integrated Microrobotic Platform for On-Demand, Targeted Therapeutic Interventions"), first-authored by Sakar's co-researcher Stefano Fusco, the team fabricated an untethered, self-folding, soft microrobotic platform, in which different functionalities are integrated to achieve targeted, on-demand delivery of biological agents.

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Jose Mejia R's comment, March 30, 2014 11:40 AM
TRADUCCION:<br>Los avances en la ingeniería de micro-y nanoescala en el campo de la medicina han conducido al desarrollo de diversos diseños robóticos que un día permitirá un nuevo nivel de la medicina mínimamente invasiva. Estos micro-y nano-robots serán capaces de llegar a un área objetiva, proporcionar tratamientos y terapias para una duración deseada, medir los efectos y, a la conclusión del tratamiento, deberá ser eliminado o degradado sin causar efectos adversos. Lo ideal sería que todas estas tareas se pueden automatizar, pero también pueden ser realizados bajo la supervisión y el control directos de un usuario externo. Varios enfoques se han explorado para el accionamiento inalámbrico de microrobots. Entre éstos, los campos magnéticos han sido la estrategia más ampliamente empleada para la propulsión, ya que no requieren propiedades especiales del medio ambiente tales como la conductividad o la transparencia (por ejemplo: "nadadores nano artificial", con un vídeo que muestra los movimientos controlados de partículas en una magnética campo).<br> <br>Este enfoque permite la manipulación precisa de objetos magnéticos hacia lugares específicos, y los campos magnéticos son biocompatibles, incluso a intensidades de campo relativamente altas (MRI). En un nuevo trabajo, un equipo de investigadores de ETH Zurich y la Universidad de Harvard (el laboratorio de David Mooney) demuestran que con inteligencia adicional - incluyendo detección y actuación - se puede crear instancias de estos microrobots seleccionando materiales y procedimientos para el proceso de fabricación adecuadas.<br><br>"Nuestro trabajo combina el diseño y la fabricación de la luz en el infrarrojo cercano (NIR) cápsulas de hidrogel sensible y microgeles magnéticas biocompatibles con un sistema de manipulación magnética para realizar tareas de administración de drogas y de suministro de células específicas, nos diece el Dr. Mahmut Sakar Selman, un científico de investigación en el Instituto de Bradley Nelson de Robótica y Sistemas Inteligentes en la ETH Zurich. Sus resultados indicados el 04 de noviembre 2013 en la edición en línea de Materiales Avanzados ...
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Unravelling a mystery in histones shows how gene activity is inherited

Unravelling a mystery in histones shows how gene activity is inherited | Amazing Science | Scoop.it

Histones are vitally important because every cell in the body has more than six feet of DNA bundled within a tiny nucleus, a space much smaller than can be seen with the naked eye. For such a massive amount of DNA to be compacted into a microscopic space, it must be wound tightly around spool-like assemblies of proteins. Each of those spools is made up of eight histone proteins. It takes millions of spools in every cell to bundle the entire genome.

Histone proteins are marked with chemical tags, such as methyl groups. The histone code consists of the patterns formed by such marks, across the full genome. The marks are sometimes called epigenetic marks. The code consisting of these marks provides instructions that cause cells to turn specific genes on or off. 

There are numerous types of histones, and small variations in their structure enable them to perform distinct specialized functions. Scientists have found that one histone, known as H3, comes in two subtypes, called H3.1 and H3.3. These variants are found in very different places in the genome: version H3.1 is found only in parts of the genome where genes are not being activated; version H3.3 is present only in places where genes are active. Scientists have long wondered what it is about these two variants that accounts for their different associations with genes – H3.1 with inactive genes and H3.3 with active ones.

In a paper published today in Science, a team led by CSHL Professor and HHMI Investigator Robert Martienssen and Professor Jean-François Couture of the University of Ottawa announces that they have solved the mystery, exploiting unique aspects of plant genomes. They have discovered that a single amino acid difference in the structure of histone H3.3 enables it to serve as a kind of memory device for the cell, marking genes that need to remain active. 

Martienssen, Couture, and Yannick Jacob, Ph.D., a postdoctoral fellow at CSHL and lead author on the paper, found that the key was a single epigenetic modification. The team, in collaboration with Professor Danny Reinberg from New York University, found that H3.1 can be modified with a methylation mark in a way that H3.3 cannot be. This chemical modification acts as a flag, signaling to the cell that genes in the vicinity should be inactive, or silent.  “Our findings highlight the remarkable impact that subtle structural differences between histone H3 variants has in the global landscape of epigenetics,” says Couture.

This distinction is especially important when a cell copies its genetic material, which happens just prior to cell division.  As the cell replicates its DNA, it must also preserve the epigenetic marks that delineate active and inactive areas of the genome.  In fact, silencing machinery, which deposits methylation marks on H3.1, works in tandem with the replication machinery. “Because H3.3 can’t carry this modification, its presence on active genes allows them to escape silencing,” says Jacob.  “In our research, we discovered a way for cells to protect active genes from silencing and preserve that memory through successive cellular generations.” 

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Nineteen new praying mantis species discovered in Central and South America

Nineteen new praying mantis species discovered in Central and South America | Amazing Science | Scoop.it

Nineteen new species of a tree-living praying mantis family have been discovered, tripling the group’s diversity at a stroke.


The bark mantises (Liturgusa Saussure) from Central and South America were found in tropical forests and among specimens kept in museums.

Many of the newly described species are known only from a few specimens collected before 1950 from locations now heavily impacted by agriculture or urban development.


“Based on this study, we can predict that mantis groups with similar habitat specialization in Africa, Asia and Australia will also be far more diverse than what is currently known,” said Dr Gavin Svenson, curator of invertebrate zoology at the Cleveland Museum of Natural History in the US.


“Many of these groups have never been studied other than by the scientists that originally described some of the species, which in some cases is more than 100 years ago. This is exciting because enormous potential exists for advancing our understanding of praying mantis diversity just by looking within our existing museum collections and conducting a few field expeditions.”

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Michael Mazo's curator insight, December 13, 2014 8:34 PM

Species are being discovered everyday, from bacteria to strains of infectious virus. Many of these new founded species originate in suitable living conditions like the one we find in Central America. This article gave in-depth context the new praying mantis species found in Central America. I thought a finding a couple new species would be remarkable but to find 19 different species of the praying mantis is beyond just an achievement. The habitat in this area allows for a creature like the praying mantis to thrive in Central America. Im sure this won't be the last species found in such a diverse location 

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Biologists discover fish with a previously unknown type of eye

Biologists discover fish with a previously unknown type of eye | Amazing Science | Scoop.it

The University of Tübingen's Institute of Anatomy has discovered a fish with a previously unknown type of eye. The aptly-named glasshead barreleye lives at depths of 800 to 1000 meters. It has a cylindrical eye pointing upwards to see prey, predators or potential mates silhouetted against the gloomy light above. But the eye also has a mirror-like second retina which can detect bioluminescent flashes created by deep-sea denizens to the sides and below, reports Professor Hans-Joachim Wagner in the latest Proceedings of the Royal Society B.

Professor Wagner examined an 18cm long glasshead barreleye, rhynchohyalus natalensis, caught in the Tasman Sea between Australia and New Zealand, as part of an international research project. The results were unexpected – reflector eyes are usually only found in invertebrates, such as mollusks and crustaceans, although one other vertebrate, the deep-sea brownsnout spookfish or dolichopteryx longipes, also uses a combination of reflective and refractive lenses in its eyes. The light coming from below is focused onto a second retina by a curved mirror composed of many layers of small reflective plates made of guanine crystals, giving the fish a much bigger field of vision.


The glasshead barreleye is therefore one of only two vertebrates known to have reflector eyes; but significantly, although rhynchohyalus natalensis and dolichopteryx longipes belong to the same family, their reflective lenses have a different structure and appear to have developed from different kinds of tissue. That indicates that two related but different genera took different paths to arrive at a similar solution – the reflective optics and a second retina to supplement the limited vision of the conventional refractive cylindrical eye.

The prisms in the brownsnout spookfish eye grew out of a layer of pigment on the retina and the angle of the reflective crystals varies depending on their position within the mirror, but in the glasshead barreleye, the crystals are flatter and images are formed depending on the roundness of the reflective surface. "The mirror here is formed from the silvery skin of the eye, and the crystals are arrayed almost parallel to the surface of the mirror," says Wagner. Models of the reflector showed that it is capable of throwing a bright, sharp image onto the retina below. "Obviously, a broad field of vision is an advantage even at great depths if similar structures develop independently to ensure it."

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Humans can distinguish at least one trillion different odors, study shows

Humans can distinguish at least one trillion different odors, study shows | Amazing Science | Scoop.it

In a world perfumed by freshly popped popcorn and exhaust fumes, where sea breezes can mingle with the scents of sweet flowers or wet paint, new research has found that humans are capable of discriminating at least one trillion different odors. Howard Hughes Medical Institute (HHMI) scientists determined that our sense of smell is prepared to recognize this vast olfactory palette after testing individuals' ability to recognize differences between complex odors mixed in the laboratory.


It has been said for decades that humans are capable of discriminating between 10,000 different odors. The number is cited in scientific literature and appears in popular magazines. "It's the generally accepted number," says HHMI investigator Leslie Vosshall, who studies olfaction at the Rockefeller University. "Our analysis shows that the human capacity for discriminating smells is much larger than anyone anticipated."


Vosshall and her colleagues published their findings March 21, 2014, in the journalScience. "I hope our paper will overturn this terrible reputation that humans have for not being good smellers," she says.

Vosshall had long been bothered by the idea that humans were limited to smelling 10,000 odors – an estimate that was made in the 1920s, and not backed by any data. "Objectively, everybody should have known that that 10,000 number had to be wrong," she says. For one thing, it didn't make sense that humans should sense far fewer smells than colors. In the human eye, Vosshall explains, three light receptors work together to see up to 10 million colors. In contrast, the typical person's nose has 400 olfactory receptors.


But no one had tested humans' olfactory capacity. "We know exactly the range of sound frequencies that people can hear, not because someone made it up, but because it was tested. We didn't just make up the fact that humans can't see infrared or ultraviolet light. Somebody took the time to test it," Vosshall says. "For smell, nobody ever took the time to test."


Vosshall and Andreas Keller, a senior scientist in her lab at Rockefeller University, knew they couldn't test people's reactions to 10,000 or more odors, but they knew they could come up with a better estimate. They devised a strategy to present their research subjects with complex mixtures of different odors, and then ask whether their subjects could tell them apart.


They used 128 different odorant molecules to concoct their mixtures. The collection included diverse molecules that individually might evoke grass, or citrus, or various chemicals. But when combined into random mixtures of 10, 20, or 30, Vosshall says, they became largely unfamiliar. "We didn't want them to be explicitly recognizable, so most of our mixtures were pretty nasty and weird," she says. "We wanted people to pay attention to 'here's this really complex thing – can I pick another complex thing as being different?'"


The scientists presented their volunteers with three vials of scents at a time: two matched, and one different. Volunteers were asked to identify the one scent that was different from the others. Each volunteer made 264 such comparisons. Vosshall and her colleagues tallied how often their 26 subjects were able to correctly identify the correct outlier. From there, they extrapolated how many different scents the average person would be able to discriminate if they were presented with all the possible mixtures that could be made from their 128 odorants. "It's like the way the census works: to count the number of people who live in the United States, you don't knock on every single door, you sample and then extrapolate," she explains. "That's how I like to think of this study. We knocked on a few doors." In this way, they estimated that the average person can discriminate between at least one trillion different odors.


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mirikelam's curator insight, February 18, 2015 4:02 AM

Prêts pour de nouvelles découvertes olfactives !

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Nanoscale optical switch breaks miniaturization barrier

Nanoscale optical switch breaks miniaturization barrier | Amazing Science | Scoop.it

A new ultra-fast, ultra-small optical switch could advance the day when photons replace electrons in consumer products ranging from cell phones to automobiles. It was developed by a team of scientists from Vanderbilt University, University of Alabama-Birmingham, and Los Alamos National Laboratory.


Described in the March 12 issue of the journal Nano Letters, the new optical device can turn on and off trillions of times per second. It consists of individual switches that are only 200 nanometers in diameter — much smaller than the current generation of optical switches. It overcomes one of the major technical barriers to the spread of electronic devices that detect and control light: miniaturizing the size of ultrafast optical switches.


The ultrafast switch is made out of a metamaterial (artificial material) engineered to have properties that are not found in nature. The metamaterial consists of nanoscale particles of vanadium dioxide (VO2) — a crystalline solid that can rapidly switch back and forth between an opaque, metallic phase and a transparent, semiconducting phase — which are deposited on a glass substrate and coated with a “nanomesh” of tiny gold nanoparticles.

The scientists report that bathing these gold nanoparticles with brief pulses from an ultrafast laser generates hot electrons in the gold particles that jump into the vanadium dioxide and cause it to undergo its phase change in a few trillionths of a second.


“We had previously triggered this transition in vanadium dioxide nanoparticles directly with lasers and we wanted to see if we could do it with electrons as well,” said Richard Haglund, Stevenson Professor of Physics at Vanderbilt, who led the study. “Not only does it work, but the injection of hot electrons from the gold nanoparticles also triggers the transformation with one fifth to one tenth as much energy input required by shining the laser directly on the bare VO2.”


Both industry and government are investing heavily in efforts to integrate optics and electronics, because it is generally considered to be the next step in the evolution of information and communications technology. Intel, Hewlett-Packard and IBM have been building chips with increasing optical functionality for the last five years that operate at gigahertz speeds, one thousandth that of the VO2 switch.

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Scientists are making paint that never fades, by mimicking iridescent bird feathers

Scientists are making paint that never fades, by mimicking iridescent bird feathers | Amazing Science | Scoop.it

Among the taxidermal specimens in Harvard’s Museum of Comparative Zoology, past centuries-old fur coats, arises a flicker of brilliant blue. This is the spangled cotinga. Surprisingly, the cotinga is about as old as everything in the room, but its color is still as dazzling as the day it was brought to the museum. The cotinga—or rather its feathers—achieve this effect through structural color.


Unlike color that we usually think of, which arises from paints and dyes absorbing certain wavelengths of light and reflecting the remainder, structural color is created when an object’s very nanostructure amplifies a specific wavelength. Cells in the cotinga’s feathers have a series of tiny pores spaced just right so that blues (and not much of anything else) are reflected back to our eyes. Because of this, if the feathers were thoroughly pulverized, the formation of pores and therefore the color would be lost. It also means that the same color could be produced from an entirely different material, if one could recreate the same pattern made by the feathers' pores.


Researchers led by Vinothan N. Manoharan at the Harvard School of Engineering and Applied Sciences want to recreate this effect, giving man-made materials structural color. Producing structural color is not easy, though; it often requires a material’s molecules to be in a very specific crystalline pattern, like the natural structure of an opal, which reflects a wide array of colors. But the pores on the cotinga’s feathers lack a regular order and are therefore a prime target for imitation.


Manoharan's lab has devised a system where microcapsules are filled with a disordered solution of even smaller particles suspended in water. When the microcapsule is partly dried out, it shrinks, bringing the particles closer and closer together. Eventually the average distance between all the particles will give rise to a specific reflected color from the capsule. Shrink the capsule a bit more, and they become another color, and then another.


“Most color you get in paints, coatings or cosmetics, even, comes from the selective absorption and reflection of light. What that means is that the material is absorbing some energy, and that means that over time, the material will fade,” says Manoharan.


The sun’s energy pummels the molecules in conventional pigments. Eventually, the molecules simply deteriorate and no longer absorb the colors they used to, leading to sun bleaching. Manoharan’s group is currently testing their innovation to see if it can create an effectively ageless color.


Electronic display technology—for example, e-readers—might also benefit from this advance. The microcapsules could be used in displays that create pixels with colored particles rather than LEDs, liquid crystals, or black-and-white “electronic ink.”


“We think it could be possible to create a full-color display that won’t fade over time,” says Manoharan. “The dream is that you could have a piece of flexible plastic that you can put graphics on in full color and read in bright sunlight.”

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Three-Fourths of Flu-Infected People Won’t Know It: Study Shows

Three-Fourths of Flu-Infected People Won’t Know It: Study Shows | Amazing Science | Scoop.it
Nearly three fourths of all influenza infections each season are asymptomatic, according to a recent study, indicating officials know less about the influenza virus than once thought.


Influenza causes roughly 250 000—500 000 deaths worldwide each year.[1] In the 20th century there were three influenza pandemics for which there are varying mortality estimates: 1918 A/H1N1 at least 20—40 million excess deaths, 1957 A/H2N2 about 4 million excess deaths, and 1968 A/H3N2 about 2 million excess deaths.[2—4] In 2009 a new pandemic virus,[5] influenza A(H1N1) pdm09, emerged in Mexico[6] and spread globally over 2009—10, causing an estimated 200 000 respiratory deaths and 83 000 cardiovascular deaths during the first 12 months of circulation.[7] WHO declared an end to the pandemic on Aug 10, 2010.[8] However, a further pandemic wave occurred in some European and other countries outside North America[9] in 2010—11 with reports of excess deaths in, for example, England.[10]

Internationally, influenza activity surveillance provides real-time information to inform prevention and control policy.[11] Surveillance focuses on cases seeking medical attention: the so-called tip of the iceberg of infection. Underestimation of the number of community cases leads to overestimates of severity.[12, 13] Heightened concern during a pandemic can change patient consultation thresholds and clinician recording and investigation behavior, thus distorting surveillance information.[14] Information on the community burden of influenza is key to informing control,[15] but is not routinely collected. For example, influenza transmission models, which are widely used to consider the efficacy and cost-effectiveness of vaccines, antivirals, and non-pharmaceutical countermeasures, depend on valid epidemiological estimates of the community occurrence of disease.

Testing the blood of the participants at the end of each season allowed researchers to conclude that while a great many participants proved to have been infected each year, approximately 77 percent of them never displayed any symptoms of infection, proving to be asymptomatic. Whether or not the flu infections cause unusual adverse symptoms in any of these infected participants remained unclear.


What does this mean? The study concluded that the human body might be more capable at fighting off or at least quelling the influenza virus than what is commonly thought. Health organization in North America and Europe both push for vaccination for the seasonal influenza virus in order to help stifle the virus's spread, but it has been revealed by past studies of these same organizations that the influenza virus only proves effective at preventing an infection 50 to 60 percent of the time.


The study was funded by the Medical Research Council and Wellcome Trust and published by The Lancet on March 17, 2014.


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'Waves' on Titan’s lakes: First liquid wave detection on the surface of another world

'Waves' on Titan’s lakes: First liquid wave detection on the surface of another world | Amazing Science | Scoop.it

Scientists believe they have detected the first liquid waves on the surface of another world. The signature of isolated ripples was observed in a sea called Punga Mare on the surface of Saturn's moon Titan. However, these seas are filled not with water, but with hydrocarbons like methane and ethane. These exist in their liquid state on Titan, where the surface temperature averages about -180C.


Planetary scientist Jason Barnes discussed details of his findings at the 45th Lunar and Planetary Science Conference (LPSC) in Texas this week. Titan is a strange, looking-glass version of Earth with a substantial atmosphere and a seasonal cycle. Wind and rain shape the surface to form river channels, seas, dunes and shorelines.


But much of what's familiar is also turned sideways: the moon's mountains and dune fields are made of ice, rather than rock or sand, and liquid hydrocarbons take up many of the roles played by water on Earth. The vast majority of Titan's lakes and seas are concentrated around the north polar region. Just one of these bodies of liquid - Ligeia Mare - is estimated to contain about 9,000 cubic km of mostly liquid methane, equating to about 40 times the proven reserves of oil and gas on Earth.


Dr Barnes, from the University of Idaho in Moscow, US, used a mathematical model to investigate whether the features in the image were compatible with waves. "We think we've found the first waves outside the Earth," he told the meeting.


"What we're seeing seems to be consistent with waves at just a few locations in Punga Mare [with a slope] of six degrees." He said other possibilities, such as a wet mudflat, could not be ruled out.


But assuming these were indeed waves, Dr Barnes calculates that a wind speed of around 0.75 m/s is required to produce ripples with the requisite slope of six degrees. That points to the waves being just 2cm high. "Don't make your surfing vacation reservations for Titan just yet," Dr Barnes quipped.


However, Titan appears to be on the brink of major seasonal changes, which present important opportunities for scientists to gain a better understanding of this complex and endlessly surprising world.

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Frozen Underground for 1,500 Years, a Moss Comes Back to Life

Frozen Underground for 1,500 Years, a Moss Comes Back to Life | Amazing Science | Scoop.it

Scientists have previously revived microbes stuck in permafrost for tens of thousands of years. But for multicellular organisms like plants and animals, the record for suspended animation has been a decade or two at most. A new study shatters that record.


A team of British researchers drilled core samples from moss beds on Signy Island, off Antarctica, and took slices from different depths back to the lab. Then they warmed up the samples in an incubator and exposed them to light to see if they could get anything to grow. They weren’t optimistic. The deepest layers from their Antarctic cores were more than 1,500 years old.


And the record for getting frozen plant material to start growing again was no more than 20 years. Among animals it’s even shorter: Brine shrimp, aka Sea Monkeys, can be rejuvenated after a couple years in dry, freezing conditions; tardigrades, bizarre little eight-legged, water-dwelling creatures, can be revived after as much as a decade.


To the researchers’ surprise even the oldest mosses in their core samples began to grow new shoots, they report today in Current Biology. Perhaps even older mosses could be coaxed into growing, they write. The oldest Antarctic moss banks are 6,000 years old.

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Elysia chlorotica, a solar-powered sea slug is an energy-efficient gene thieve

Elysia chlorotica, a solar-powered sea slug is an energy-efficient gene thieve | Amazing Science | Scoop.it

Elysia chlorotica is a “solar-powered” marine sea slug that sequesters and retains photosynthetically active chloroplasts from the algae it eats and, remarkably, has incorporated algal genes into its own genetic code. It is emerald green in color often with small red or white markings, has a slender shape typical of members of its genus, and parapodia (lateral "wings") that fold over its body in life. This sea slug is unique among animals to possess photosynthesis-specific genes and is an extraordinary example of symbiosis between an alga and mollusc as well as a genetic chimera of these two organisms.


To obtain algal chloroplasts Elysia chlorotica slugs use their radula (tooth) to pierce a filament of the alga Vaucheria litorea and suck out its contents. The ingested algal cytoplasm and nuclei move through the gut but algal chloroplasts are trapped and concentrated in vacuoles along branches of the digestive tract. While inside an algal cell, functional chloroplasts use proteins encoded by their own genes as well as others encoded by genes within the algal nucleus. Within a sea slug, however, isolated chloroplasts can not receive proteins from the algal genome. Remarkably, these chloroplasts remain functional anyway because the slug genome includes the algal genes necessary for plastid function. Elysia chlorotica probably gained these algal genes through lateral (or horizontal) gene transfer. One possible vector is a virus that infects the sea slug and carried pieces of algal DNA (Pierce et al., 2003).


More:  Scientific American blog post by Ferris Jabr.

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Soft robotic fish moves like the real thing

Soft robotic fish moves like the real thing | Amazing Science | Scoop.it

Soft robots — which don't just have soft exteriors but are also powered by fluid flowing through flexible channels — have become a sufficiently popular research topic that they now have their own journal, Soft Robotics. In the first issue of that journal, out this month, MIT researchers report the first self-contained autonomous soft robot, a "fish" that can execute an escape maneuver, convulsing its body to change direction, in just 100 milliseconds, or as quickly as a real fish can.

"We're excited about soft robots for a variety of reasons," says Daniela Rus, a professor of computer science and engineering, director of MIT's Computer Science and Artificial Intelligence Laboratory, and one of the researchers who designed and built the fish. "As robots penetrate the physical world and start interacting with people more and more, it's much easier to make robots safe if their bodies are so wonderfully soft that there's no danger if they whack you."

The robotic fish was built by Andrew Marchese, a graduate student in MIT's Department of Electrical Engineering and Computer Science and lead author on the new paper, where he's joined by Rus and postdoc Cagdas D. Onal. Each side of the fish's tail is bored through with a long, tightly undulating channel. Carbon dioxide released from a canister in the fish's abdomen causes the channel to inflate, bending the tail in the opposite direction.


The fish can perform 20 or 30 escape maneuvers, depending on their velocity and angle, before it exhausts its carbon dioxide canister. But the comparatively simple maneuver of swimming back and forth across a tank drains the canister quickly. “The fish was designed to explore performance capabilities, not long-term operation,” Marchese says. “Next steps for future research are taking that system and building something that’s compromised on performance a little bit but increases longevity.”

A new version of the fish that should be able to swim continuously for around 30 minutes will use pumped water instead of carbon dioxide to inflate the channels, but otherwise, it will use the same body design, Marchese says. Rus envisions that such a robot could infiltrate schools of real fish to gather detailed information about their behavior in the natural habitat.

“All of our algorithms and control theory are pretty much designed with the idea that we’ve got rigid systems with defined joints,” says Barry Trimmer, a biology professor at Tufts University who specializes in biomimetic soft robots. “That works really, really well as long as the world is pretty predictable. If you’re in a world that is not — which, to be honest, is everywhere outside a factory situation — then you start to lose some of your advantage.”

The premise of soft robotics, Trimmer says, is that “if we learn how to incorporate all these other sorts of materials whose response you can’t predict exactly, if we can learn to engineer that to deal with the uncertainty and still be able to control the machines, then we’re going to have much better machines.”

The MIT researchers’ robot fish “is a great demonstration of that principle,” Trimmer says. “It’s an early stage of saying, ‘We know the actuator isn’t giving us all the control we’d like, but can we actually still exploit it to get the performance we want?’ And they’re able to show that yes, they can.”

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Scientists develop new kind of internal combustion microengine 100 microns wide

Scientists develop new kind of internal combustion microengine 100 microns wide | Amazing Science | Scoop.it

A team of researchers with members from Russia, The Netherlands and Germany has developed a new kind of microengine, based on the possible combustion of oxygen and hydrogen. In their paper published in Scientific Reports, the team describes how they built the new engine, how they think it works, and what it could mean for the development of future microsystems.


As scientists have built ever smaller devices, the need for ever smaller microengines has grown, unfortunately, the science for tiny engines hasn't kept pace. Those based on electrostatic forces aren't able to produce enough power and traditional combustion engines become less and less efficient as they are made smaller. In this new effort, the researchers built a tiny combustion engine in a new way that overcomes the problems of others before it, though they can't say for sure how it works.


The engine is very simple. The team built a tiny pressure chamber with a flexible membrane at one end, they then added wires inside that ran through a saltwater solution. Sending current through the wires caused hydrogen and oxygen in the water to disassociate into tiny bubbles (i.e. electrolysis). That caused an increase in pressure inside the chamber (approximately 3.6 bar) forcing the membrane to bend outwards (approximately 1.4 microns). Turning off the current caused the membrane to return to its natural shape, but oddly, it did so much faster than it should have due to dissipation—the researchers suspect that instead the gas was combusted back into water molecules. In any event, quickly cycling back and forth a membrane can be used as a force mechanism—an engine.


Remarkably, the new microengine is just 100×100×5 microns in size and was fabricated using silicon wafers covered with a layer of silicon rich nitride and platinum electrodes. The membrane was part of the wafer, etched from the back side.


The microengine produces a lot of torque for its size, and thus could very well serve as the basis for very tiny devices that need to either perform physical work (e.g. pump fluid), or move around (perhaps inside human blood vessels). At the same time, it's a certainty that the original team and others will set to work trying to nail down exactly why the engine works and to determine just how small such an engine could be.


Referebce: New type of microengine using internal combustion of hydrogen and oxygen, Scientific Reports 4, Article number: 4296 DOI: 10.1038/srep04296

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There is an Ocean Full of Water Deep Inside the Earth

There is an Ocean Full of Water Deep Inside the Earth | Amazing Science | Scoop.it

In what sounds like a chapter from Journey to the Center of the Earth, the chemical makeup of a tiny, extremely rare gemstone has made researchers think there's a massive water reservoir hundreds of miles under the earth.


The gemstone in question is called ringwoodite, which is created when olivine, a material that is extremely common in the mantle, is highly pressurized; when it’s exposed to less pressurized environments, it reverts into olivine. It has previously been seen in meteorites and created in a laboratory, but until now it had never been found in a sample of the earth’s mantle.


Diamond expert Graham Pearson of the University of Alberta came across a seemingly worthless, three-millimeter piece of brown diamond that had been found in Mato Grosso, Brazil, while he was researching another type of mineral. Within that diamond, he and his team found ringwoodite—and they found that roughly 1.5 percent of the ringwoodite’s weight was made up of trapped water. The findings are published in Nature.


That water had to get in there somehow, and using analyses of its depth and its water makeup, Pearson suggests that there's water deep under the earth's surface—a lot of it.


The finding “confirms predictions from high-pressure laboratory experiments that a water reservoir comparable in size to all the oceans combined is hidden deep in Earth’s mantle,” according to an analysis of Pearson’s findings by Hans Keppler of the University of Bayreuth in Germany. 


The earth’s crust, including the deepest parts of the oceans, reach depths of roughly 100 kilometers. From there, the upper mantle takes up about another 300 kilometers. Between there and the lower mantle is where this piece of ringwoodite was originally from—an area between 410 and 660 kilometers beneath the earth’s surface known as the “transition zone.” 


Scientists have long been divided about what, exactly, is in the transition zone. We’ve known that much of the upper mantle is made up of olivine, and as Keppler said, scientists have long thought that Earth contained reservoirs of water deep beneath the crust. But they weren’t sure whether the water existed as low as the transition zone—the area between the upper and lower mantles. While some say that much of the oceans’ water may have originated there, others have said it is likely completely dry.


Pearson’s finding changes that. In the paper, he says that there are two possible explanations for water within the ringwoodite. “In one, water within the ringwoodite reflects inheritance from a hydrous, diamond-forming fluid, from which the inclusion grew as a syngenetic phase. In this model, the hydrous fluid must originate locally, from the transition zone, because there is no evidence that the lower mantle contains a significant amount of water,” he wrote. Essentially, the extreme pressure and chemical makeup at those depths spontaneously creates water. 


“Alternatively, the ringwoodite is ‘protogenetic,’ that is, it was present before encapsulation by the diamond and its water content reflects that of the ambient transition zone," Pearson wrote. In that model, the water and the ringwoodite are already there, and the ringwoodite absorbs some of the water. Either way you slice it, there is a lot of water in the transition zone: “Both models implicate a transition zone that is at least locally water-rich,” he wrote.


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