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According to New Findings, Subsurface Life On Mars Was Once Possible

According to New Findings, Subsurface Life On Mars Was Once Possible | Amazing Science | Scoop.it

McLaughlin Crater is 90.92 km (56.50 mi) in diameter and 2.2 km (1.4 mi) deep with a floor that is well below Martian “sealevel” and contains clays that bear iron and magnesium as well as carbonate.

 

By the time eukaryotic life or photosynthesis evolved on Earth, the martian surface had become extremely inhospitable, but the subsurface of Mars could potentially have contained a vast microbial biosphere. Crustal fluids may have welled up from the subsurface to alter and cement surface sediments, potentially preserving clues to subsurface habitability. Many ancient, deep basins lack evidence for groundwater activity. However, McLaughlin Crater, one of the deepest craters on Mars, contains evidence for Mg–Fe-bearing clays and carbonates that probably formed in an alkaline, groundwater-fed lacustrine setting. This environment strongly contrasts with the acidic, water-limited environments implied by the presence of sulphate deposits that have previously been suggested to form owing to groundwater upwelling. Deposits formed as a result of groundwater upwelling on Mars, such as those in McLaughlin Crater, could preserve critical evidence of a deep biosphere on Mars. Scientists suggest that groundwater upwelling on Mars may have occurred sporadically on local scales, rather than at regional or global scales.

 

“This environment strongly contrasts with the acidic, water-limited environments implied by the presence of sulphate deposits that have previously been suggested to form owing to groundwater upwelling.”

 

Water-made channels which are now dry, appear to flow down the walls of McLaughlin Crater and stop well above the crater floor, which indicates they once provided water to a lake. “The deposits in McLaughlin Crater could have very high preservation potential for organic materials, in much the same manner as turbidites do on Earth.”

 

Cyanobacteria, which are common in alkaline lakes on Earth may have aided in the formation of carbonate minerals in lakes such as the McLAughlin Crater on Mars. Sometimes these bacteria become form microscopic fossils. If similar conditions existed in the craters ancient alkaline lake fossils of micro-organisms may still be there awaiting us.

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20,000+ FREE Online Science and Technology Lectures from Top Universities

20,000+ FREE Online Science and Technology Lectures from Top Universities | Amazing Science | Scoop.it

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Great resources for online learning just about everything.  All you need is will power and self- discipline.

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RCas9: A Programmable RNA Editing Tool Based on CRISPR-CAS

RCas9: A Programmable RNA Editing Tool Based on CRISPR-CAS | Amazing Science | Scoop.it

A powerful scientific tool for editing the DNA instructions in a genome can now also be applied to RNA, the molecule that translates DNA's genetic instructions into the production of proteins. A team of researchers with Berkeley Lab and the University of California (UC) Berkeley has demonstrated a means by which the CRISPR/Cas9 protein complex can be programmed to recognize and cleave RNA at sequence-specific target sites. This finding has the potential to transform the study of RNA function by paving the way for direct RNA transcript detection, analysis and manipulation.


A team led by Jennifer Doudna, biochemist and leading authority on the CRISPR/Cas9 complex, showed how the Cas9 enzyme can work with short DNA sequences known as "PAM," for protospacer adjacent motif, to identify and bind with specific site of single-stranded RNA (ssRNA). They are designating this RNA-targeting CRISPR/Cas9 complex as RCas9.


In recent years, the CRISPR/Cas complex has emerged as one of the most effective tools for doing this. CRISPR, which stands for Clustered Regularly Interspaced Short Palindromic Repeats, is a central part of the bacterial immune system and handles sequence recognition. Cas9 - Cas stands for CRISPR-assisted - is an RNA-guided enzyme that handles the sniping of DNA strands at the specified sequence site. Together, CRISPR and Cas9 can be used to precisely edit the DNA instructions in a targeted genome for making desired types of proteins. The DNA is cut at a specific location so that old DNA instructions can be removed and/or new instructions inserted. Until now, it was thought that Cas9 could not be used on the RNA molecules that transcribe those DNA instructions into the desired proteins.


"Just as Cas9 can be used to cut or bind DNA in a sequence-specific manner, RCas9 can cut or bind RNA in a sequence-specific manner," says Mitchell O'Connell, a member of Doudna's research group and the lead author of a paper in Nature that describes this research titled "Programmable RNA recognition and cleavage by CRISPR/Cas9." Doudna is the corresponding author. Other co-authors are Benjamin Oakes, Samuel Sternberg, Alexandra East Seletsky and Matias Kaplan.


In an earlier study, Doudna and her group showed that the genome editing ability of Cas9 is made possible by presence of PAM, which marks where cutting is to commence and activates the enzyme's strand-cleaving activity. In this latest study, Doudna, Mitchell and their collaborators show that PAMmers, in a similar manner, can also stimulate site-specific endonucleolytic cleavage of ssRNA targets. They used Cas9 enzymes from the bacterium Streptococcus pyogenes to perform a variety of in vitro cleavage experiments using a panel of RNA and DNA targets.


"While RNA interference has proven useful for manipulating gene regulation in certain organisms, there has been a strong motivation to develop an orthogonal nucleic-acid-based RNA-recognition system such as RCas9," Doudna says. "The molecular basis for RNA recognition by RCas9 is now clear and requires only the design and synthesis of a matching guide RNA and complementary PAMmer."

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Using monoclonal antibodies produced in plants to fight off a lethal virus like Ebola

Using monoclonal antibodies produced in plants to fight off a lethal virus like Ebola | Amazing Science | Scoop.it

Kevin Whaley, the CEO at Mapp Bio isn't much given to publicly discussing ZMapp, the remarkable new treatment for Ebola, at all. At a time when every public biotech company with a preclinical program for Ebola is clamoring for attention, Whaley has given precious few interviews. And when he has talked about ZMapp, he's been careful to say that the company doesn't know whether it works and has lots more work to do. If anything, the air of mystery has only heightened the lurid 24/7 cable news attention given to ZMapp, which could help revolutionize the way in which outbreaks are treated in years to come.


ZMapp is a cocktail therapy made up of antibodies that Mapp's small team of 9 has assembled into a single treatment. For a vaccine, investigators would work on delivering antibodies that would prime the human immune system to fight off a lethal virus like Ebola. But for people who are already infected, facing about a 50% mortality rate, this new approach has the potential to provide a powerful and immediate response.


ZMapp includes antibodies that were generated in mouse models exposed to an Ebola protein, then "humanized" to prevent rejection, transferred to tobacco plants through a benign plant virus--or vector--and grown in the genetically engineered tobacco leaves, which are harvested to produce the therapy. The cocktail includes antibodies licensed from Defyrus and USAMRIID, all drawn by the notion that a cocktail therapy would prove to be a patient's best shot at survival. That combination of antibodies in the cocktail represents the culmination of 10 years of work, and it was only arrived at in January.


The NIH unintentionally helped get the media frenzy started when they supplied a few doses to treat two Western Ebola victims, who appear to have responded very well and are now recovering. In a matter of weeks, Mapp nailed another impressive primate study, saving all the infected animals from a likely death. The U.S. government followed up with a contract worth up to $42 million to speed up work on production. The helter-skelter development effort was pointed down the path to a quick approval as Mapp's slow-motion progress of recent years collided with the fact that only one Ebola treatment was in the clinic, and that one had been under a clinical hold at the FDA before regulators immediately cleared it for production.


Enormous logistical issues remain. In addition to the clinical program that's needed to fully test the safety and efficacy of the treatment in humans, the treatment would need to be made in large quantities in order to combat the worst outbreak health officials have seen since Ebola first appeared in 1976. Currently, only one biologic is approved for manufacturing in plants, and that is Protalix's ($PLXGaucher'sdrug, which is made in plant cells. Kentucky BioProcessing currently makes ZMapp, using vector technology from Icon Genetics. But even with a huge effort, KBP would need months to scale up production.


South African officials say they have been approached about building a facility, which would take time, while Protalix has had to walk back some statements implying that they could adapt their manufacturing process to churn out ZMapp.


ZMapp™ is the result of a collaboration between Mapp Biopharmaceutical, Inc. and  LeafBio (San Diego, CA), Defyrus Inc (Toronto, Canada), the U.S. government and the Public Health Agency of Canada (PHAC). ZMapp™ is composed of three “humanized” monoclonal antibodies manufactured in plants, specifically Nicotiana. It is an optimized cocktail combining the best components of MB-003 (Mapp) and ZMAb (Defyrus/PHAC).


ZMappTM was first identified as a drug candidate in January 2014 and has not yet  been evaluated for safety in humans. As such, very little of the drug is currently available. Any decision to use an experimental drug in a patient would be a decision made by the treating physician under the regulatory guidelines of the FDA.


Mapp and its partners are cooperating with appropriate government agencies to increase production as quickly as possible. Two partnerships were crucial to us in the development of the plant system for ZMappTM: Icon Genetics AG (Halle, Germany) and Kentucky BioProcessing (KBP,
Owensboro, KY). Icon pioneered vectors for engineering Nicotiana to produce biopharmaceuticals. KBP specializes in GMP manufacturing of therapeutic proteins in Nicotiana.

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6 mKelvin: The drive to create the coldest cubic meter in the universe

6 mKelvin: The drive to create the coldest cubic meter in the universe | Amazing Science | Scoop.it

An international team of scientists recently set a world record by cooling a copper vessel with a volume of a cubic meter down to a temperature of 6 milliKelvins—or -273.144 degrees Celsius. It was the first experiment to chill an object so large this close to absolute zero.


The collaboration, called CUORE (Cryogenic Underground Observatory for Rare Events), involves 130 scientists from the United States, Italy, China, Spain, France, and other countries. It is based at the underground Gran Sasso National Laboratory of the Instituto Nazionale di Fisica Nucleare, in Italy.


"This is a major technological achievement," said Karsten Heeger, a professor of physics at Yale and director of Yale's Arthur W. Wright Laboratory. CUORE is part of the new experimental program in neutrinos and dark matter pursued at the Wright Lab.


Yale physicists are building and testing instrumentation that will be used at temperatures of 10mK in the experiment's cryostat, which is the chilled chamber. Reina Maruyama, an assistant professor of physics, is one of the original proponents for the US involvement in CUORE and is a coordinator of its data analysis


"In collaboration with the University of Wisconsin, we have developed a detector calibration system that will deploy radioactive sources into the coldest region of the cryostat and characterize our detectors," Heeger said.


Once the CUORE experiment is fully operational, it will study important properties of neutrinos, the fundamental, subatomic particles that are created by radioactive decay and do not carry an electrical charge.


Specifically, the experiment will look at a rare process called neutrinoless double-beta decay. The detection of this process would let researchers demonstrate, for the first time, that neutrinos and antineutrinos are the same—thereby offering a possible explanation for the abundance of matter, rather than anti-matter, in the universe.


The experiment uses heat-sensitive detectors that operate in extremely cold temperatures. "It poses a unique challenge," Heeger said. "We are trying to detect a minuscule amount of heat from nuclear decay, but need to know this very precisely. The detector calibration will tell us if we see the heat from double-beta decay or environmental backgrounds."

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Tarantula toxin is used to report electrical activity inside live cells

Tarantula toxin is used to report electrical activity inside live cells | Amazing Science | Scoop.it

Crucial experiments to develop a novel probe of cellular electrical activity were conducted in the Neurobiology course at the Marine Biological Laboratory (MBL) in 2013. Now, that optical probe, which combines a tarantula toxin with a fluorescent compound, is introduced in a paper in the Proceedings of the National Academy of Sciences.

The lead authors of the paper are Drew C. Tilley of UC-Davis and the late Kenneth Eum, a Ph.D. candidate at UC-Davis and teaching assistant in the MBL Neurobiology course. The probe takes advantage of the potent ability of tarantula toxin to bind to electrically active cells, such as neurons, while the cells are in a resting state. The team discovered that a trace amount of toxin combined with a fluorescent compound would bind to a specific subset of voltage-activated proteins (Kv2-type potassium ion channels) in live cells. The probe lights up cell surfaces with this ion channel, and the fluorescent signal dims when the channel is activated by electrical signals.


This is the first time that researchers have been able to visually observe these ion channels "turning on" without first genetically modifying them. All that is required is a means to detect probe location, suggesting that related probes could potentially one day be used to map neural activity in the human brain.


"This is a demonstration, a prototype probe. But the promise is that we could use it to measure the activity state of the electrical system in an organism that has not been genetically compromised," says senior author Jon Sack, an assistant professor in the departments of Physiology and Membrane Biology at UC-Davis. Sack is a faculty member in the MBL Neurobiology course.


Since the probe binds selectively to one of the many different kinds of ion channels, it can help scientists disentangle the function of those specific channels in neuronal signaling. This can, in turn, lead to the identification of drug targets for neurological diseases and disorders.

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Bio-Inspired ‘Nano-Cocoons’ Offer Targeted Drug Delivery Against Cancer Cells

Bio-Inspired ‘Nano-Cocoons’ Offer Targeted Drug Delivery Against Cancer Cells | Amazing Science | Scoop.it

Biomedical engineering researchers have developed a drug delivery system consisting of nanoscale “cocoons” made of DNA that target cancer cells and trick the cells into absorbing the cocoon before unleashing anticancer drugs. The work was done by researchers at North Carolina State University and the University of North Carolina at Chapel Hill.


“This drug delivery system is DNA-based, which means it is biocompatible and less toxic to patients than systems that use synthetic materials,” says Dr. Zhen Gu, senior author of a paper on the work and an assistant professor in the joint biomedical engineering program at NC State and UNC Chapel Hill.


“This technique also specifically targets cancer cells, can carry a large drug load and releases the drugs very quickly once inside the cancer cell,” Gu says. “In addition, because we used self-assembling DNA techniques, it is relatively easy to manufacture,” says Wujin Sun, lead author of the paper and a Ph.D. student in Gu’s lab.


Each nano-cocoon is made of a single strand of DNA that self-assembles into what looks like a cocoon, or ball of yarn, that measures 150 nanometers across. The core of the nano-cocoon contains the anticancer drug doxorubicin (DOX) and a protein called DNase. The DNase, an enzyme that would normally cut up the DNA cocoon, is coated in a thin polymer that traps the DNase like a sword in a sheath.


The surface of the nano-cocoon is studded with folic acid ligands. When the nano-cocoon encounters a cancer cell, the ligands bind the nano-cocoon to receptors on the surface of the cell – causing the cell to suck in the nano-cocoon.


Once inside the cancer cell, the cell’s acidic environment destroys the polymer sheath containing the DNase. Freed from its sheath, the DNase rapidly slices through the DNA cocoon, spilling DOX into the cancer cell and killing it.


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Hendo Hover: First prototype of a Marty McFly hoverboard

Hendo Hover: First prototype of a Marty McFly hoverboard | Amazing Science | Scoop.it

It's impossible to talk about hoverboards without invoking a particular movie title, so we're not even going to try: Remember that awesome scene from Back to the Future Part II? It's one step closer to reality: A California startup just built a real, working hoverboard. Arx Pax is attempting to crowdfund the Hendo Hoverboard as a proof of concept for its hover engine technology -- it's not quite the floating skateboard Marty McFly rode through Hill Valley (and the Wild West), but it's an obvious precursor to the imagined ridable: a self-powered, levitating platform with enough power to lift a fully grown adult.


I initially approached the floating pallet with caution, expecting it to dip and bob under my weight like a piece of driftwood. It didn't. The levitating board wiggled slightly under my 200-pound frame, but maintained its altitude (a mere inch or so) without visible strain. Arx Pax tells me that the current prototype can easily support 300 pounds and future versions will be able to hold up to 500 pounds without issue. Either way, you'll need to hover over a veryspecific kind of surface to get it to hold anything: The Hendo uses the same kind of electromagnetic field technology that floats MagLev trains -- meaning it will only levitate over non-ferrous metals like copper or aluminum.


Riding the contraption was a lot fun, but also quite the challenge: The Hendo hoverboard doesn't ride at all like McFly's flying skateboard. In fact, without a propulsion system, it tends to drift aimlessly. Arx Pax founder and Hendo inventor Greg Henderson says it's something the company is working on. "We can impart a bias," he tells me, pointing out pressure-sensitive pads on the hoverboard's deck that manipulate the engines. "We can turn on or off different axes of movement." Sure enough, leaning on one side of the board convinces it to rotate and drift in the desired direction. Without feeling the friction of the ground, however, I had trouble knowing how much pressure to exert -- Henderson's staff had to jump in and save me from spinning out of control. Clearly, this might take some practice.


As fun as its current form is, Henderson didn't necessarily set out to reinvent transportation. The Hendo engine's original inspiration came from architecture. "It came from the idea of hovering a building out of harm's way," he says. "If you can levitate a train that weighs 50,000 kilograms, why not a house?" After some prodding, he clarifies the idea as a sort of emergency lifting system that could theoretically raise a building off of its foundation during an earthquake, essentially rendering the natural disaster's tremors harmless. The idea sounds as fictional as, well, a hoverboard -- but he already built one of those.

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UCSC Ebola genome browser now online to aid researchers' response to crisis

UCSC Ebola genome browser now online to aid researchers' response to crisis | Amazing Science | Scoop.it

The UC Santa Cruz Genomics Institute late Tuesday (September 30) released a new Ebola genome browser to assist global efforts to develop a vaccine and antiserum to help stop the spread of the Ebola virus.

The team led by University of California, Santa Cruz researcher Jim Kent worked around the clock for the past week, communicating with international partners to gather and present the most current data. The Ebola virus browser aligns five strains of Ebola with two strains of the related Marburg virus. Within these strains, Kent and other members of the UC Santa Cruz Genome Browser team have aligned 148 individual viral genomes, including 102 from the current West Africa outbreak.

UC Santa Cruz has established the UCSC Ebola Genome Portal, with links to the new Ebola genome browser as well as links to all the relevant scientific literature on the virus. 

“Ebola has been one of my biggest fears ever since I learned about it in my first microbiology class in 1997," said Kent, who 14 years ago created the first working draft of the human genome.  "We need a heroic worldwide effort to contain Ebola. Making an informatics resource like the genome browser for Ebola researchers is the least we could do.”

Scientists around the world can access the open-source browser to compare genetic changes in the virus genome and areas where it remains the same. The browser allows scientists and researchers from drug companies, other universities, and governments to study the virus and its genomic changes as they seek a solution to halt the epidemic. 

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Algae deliver hydrogen at a 5 times higher efficiency

Algae deliver hydrogen at a 5 times higher efficiency | Amazing Science | Scoop.it
Hydrogen as a regenerative fuel produced in gigantic water tanks full of algae, which need nothing more than sunlight to produce the promising green energy carrier: a great idea in theory, but one that fails due to the vast amount of space required for the production process. Scientists from the Max Planck Institutes for Chemical Energy Conversion and Coal Research) in Mülheim an der Ruhr, and from the research group Photobiotechnology at Ruhr-Universität Bochum (RUB) have now discovered a way of increasing the efficiency of hydrogen production in microalgae by a factor of five. If the algae can generate the fuel more efficiently, it can be produced in a smaller area and in quantities suitable for practical use. This approach also dispenses with the need for rare and expensive precious metals, which are used to split the energy-rich gas is technically from water.

Living organisms need electrons in many places, as they use them to form chemical compounds. Algae and other organisms which carry out photosynthesis release electrons from water with the help of sunlight and then distribute them in the cell. The ferrous protein PETF is responsible for this: It transports the electrons in particular to ferredoxin-NADP+ oxidoreductase (FNR), so that NADPH is formed and carbohydrates are finally synthesised from carbon dioxide. The production of hydrogen through hydrogenases is among the many other processes, for which PETF provides the necessary electrons.

Hydrogenases are very efficient enzymes that contain a unique active centre comprising six iron atoms, where the electrons supplied by PETF are bound to protons. Molecular hydrogen is produced in this way.

With the help of nuclear magnetic resonance spectroscopy, on which magnetic resonance imaging in medicine is also based, the scientists working with Sigrun Rumpel, a post doc at the Max Planck Institute for Chemical Energy Conversion in Mülheim, investigated the components of PETF – or more precisely amino acids – that interact with the hydrogenase and those that interact with FNR. It emerged that only two amino acids of PETF are important for binding FNR. When the researchers modified these two amino acids and the enzyme FNR, PETF was no longer able to bind FNR as efficiently. Thus, the enzyme transferred less electrons to FNR and more to the hydrogenase. In this way, the scientists increased the hydrogen production by a factor of five.


“For a technically feasible hydrogen production with the help of algae, its efficiency must be increased by a factor of 10 to 100 compared to the natural process,” says Sigrun Rumpel. “Through the targeted modification of PETF and FNR we have taken a step towards achieving this objective.” Up to now, the production of hydrogen from renewable energy carriers involved the electrolytic splitting of water. Expensive and rare precious metals like platinum are currently required for this purpose. Sigrun Rumpel and other researchers are therefore working on finding a way of enabling algae to efficiently produce the fuel. Microalgae produce the gas naturally, but in very small volumes. Thus, if cars were to be powered one day using hydrogen rather than petrol or diesel, to come anywhere near covering Germany’s fuel requirements, gigantic areas with tanks full of algal cultures would have to be set up.


“These results represent a path to the economically-viable regenerative production of fuels with the help of microalgae,” says Sigrun Rumpel. The change of electron transfer pathways could further improve hydrogen production in future. The researchers therefore now want to combine different modifications with each other.

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Puzzling new behaviour observed in high-temperature superconductors

Puzzling new behaviour observed in high-temperature superconductors | Amazing Science | Scoop.it

An international team of researchers from SLAC National Accelerator Laboratory and Stanford University and the Paul Scherrer Institute (Villigen, Switzerland) has observed a new, unexpected kind of behavior in copper-based high-temperature superconductors – materials that are capable of conducting electric current without any loss when cooled to low enough temperatures. Explaining the new phenomenon - a new, unexpected form of collective movement of the electrical charges in the material - poses a major challenge for the researchers. A success in explaining the phenomenon might be an important step toward understanding high-temperature superconductivity in general. The crucial experiments were conducted at the Paul Scherrer Institute's Swiss Light Source. The results of this project have been published in the journal Nature Physics on 19 October 2014.

Superconductivity is a phenomenon occurring in certain materials generally at very low temperatures, characterized by exactly zero electrical resistance and the exclusion of the interior magnetic field (the Meissner effect). It was discovered by Heike Kamerlingh Onnes in 1911. Like ferromagnetism and atomic spectral lines, superconductivity is a quantum mechanical phenomenon. It cannot be understood simply as the idealization of "perfect conductivity" in classical physics.


The electrical resistivity of a metallic conductor decreases gradually as the temperature is lowered. However, in ordinary conductors such as copper and silver, impurities and other defects impose a lower limit. Even near absolute zero a real sample of copper shows a non-zero resistance. The resistance of a superconductor, despite these imperfections, drops abruptly to zero when the material is cooled below its "critical temperature". An electric current flowing in a loop of superconducting wire can persist indefinitely with no power source.


Superconductivity occurs in a wide variety of materials, including simple elements like tin and aluminium, various metallic alloys and some heavily-doped semiconductors. Superconductivity does not occur in noble metals like gold and silver, nor in pure samples of ferromagnetic metals.

In 1986 the discovery of a family of cuprate-perovskite ceramic materials known as high-temperature superconductors, with critical temperatures in excess of 90 kelvin, spurred renewed interest and research in superconductivity for several reasons. As a topic of pure research, these materials represented a new phenomenon not explained by the current theory. In addition, because the superconducting state persists up to more manageable temperatures, past the economically-important boiling point of liquid nitrogen (77 kelvin), more commercial applications are feasible, especially if materials with even higher critical temperatures could be discovered.

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Physicists build reversible hollow laser tractor beam

Physicists build reversible hollow laser tractor beam | Amazing Science | Scoop.it

Laser physicists have built a tractor beam that can repel and attract objects, using a hollow laser beam that is bright around the edges and dark in its center.


It is the first long-distance optical tractor beam and moved particles one fifth of a millimeter in diameter a distance of up to 20 centimeters, around 100 times further than previous experiments. “Demonstration of a large scale laser beam like this is a kind of holy grail for laser physicists,” said Professor Wieslaw Krolikowski, from the Research School of Physics and Engineering.


The new technique is versatile because it requires only a single laser beam. It could be used, for example, in controlling atmospheric pollution or for the retrieval of tiny, delicate or dangerous particles for sampling. The researchers can also imagine the effect being scaled up.


“Because lasers retain their beam quality for such long distances, this could work over meters. Our lab just was not big enough to show it,” said co-author Dr Vladlen Shvedov, a driving force behind the ANU project, along with Dr Cyril Hnatovsky. Unlike previous techniques, which used photon momentum to impart motion, the ANU tractor beam relies on the energy of the laser heating up the particles and the air around them. The ANU team demonstrated the effect on gold-coated hollow glass particles.

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NASA: Frozen or Partially Liquid Ocean Inside Saturn's Moon Mimas?

NASA: Frozen or Partially Liquid Ocean Inside Saturn's Moon Mimas? | Amazing Science | Scoop.it

A new study focused on the interior of Saturn's icy moon Mimas suggests its cratered surface hides one of two intriguing possibilities: Either the moon's frozen core is shaped something like a football, or the satellite contains a liquid water ocean. Researchers used numerous images of Mimas taken by NASA's Cassini mission to determine how much the moon wobbles as it orbits Saturn. They then evaluated several possible models for how its interior might be arranged, finding two possibilities that fit their data.The study is published in the Oct. 17 issue of the journal Science.


"The data suggest that something is not right, so to speak, inside Mimas," said Radwan Tajeddine, a Cassini research associate at Cornell University, Ithaca, New York, and lead author on the paper. "The amount of wobble we measured is double what was predicted."


Either possiblity for the interior of Mimas would be interesting, according to Tajeddine, as the moon's heavily cratered outward appearance does not suggest anything unusual lies beneath its surface. Because Mimas formed more than four billion years ago, scientists would expect its core to have relaxed into a more or less spherical shape by now. So if Mimas' core is oblong in shape, it likely represents a record of the moon's formation, frozen in time.

If Mimas possesses an ocean, it would join an exclusive club of "ocean worlds" that includes several moons of Jupiter and two other Saturn moons, Enceladus and Titan. A global ocean would be surprising, said Tajeddine, as the surface of Mimas does not display signs of geologic activity.


Like a lot of moons in the solar system, including our own, Mimas always shows essentially the same face to its parent planet. This is called a spin-orbit resonance, meaning the moon's rotation, or spin, is in sync with its orbit around Saturn. Like Earth's moon, Mimas takes the same amount of time to spin completely around on its axis as it takes to orbit its planet.


The orbit of Mimas is very slightly stretched out, forming an ellipse rather than a perfect circle. This slight deviation causes the point on Mimas' surface that faces Saturn to vary a bit over the course of an orbit -- an observer on Saturn would see Mimas wobble slightly during its orbit, causing small amounts of terrain over the limb to become visible. This effect is called libration, and Earth's moon does it as well.


"Observing libration can provide useful insights about what is going on inside a body," said Tajeddine. "In this case, it is telling us that this cratered little moon may be more complex than we thought."

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Manufacturing superconducting circuits, simplified

Manufacturing superconducting circuits, simplified | Amazing Science | Scoop.it
Computer chips with superconducting circuits—circuits with zero electrical resistance—would be 50 to 100 times as energy-efficient as today's chips, an attractive trait given the increasing power consumption of the massive data centers that power the Internet's most popular sites.


Superconducting chips also promise greater processing power: Superconducting circuits that use so-called Josephson junctions have been clocked at 770 gigahertz, or 500 times the speed of the chip in the iPhone 6.


But Josephson-junction chips are big and hard to make; most problematic of all, they use such minute currents that the results of their computations are difficult to detect. For the most part, they've been relegated to a few custom-engineered signal-detection applications.


In the latest issue of the journal Nano Letters, MIT researchers present a new circuit design that could make simple superconducting devices much cheaper to manufacture. And while the circuits' speed probably wouldn't top that of today's chips, they could solve the problem of reading out the results of calculations performed with Josephson junctions.


The MIT researchers developed a 3-terminal, nanowire-based superconducting electrothermal device which has no Josephson junctions. This device, which they call a "nanocryotron"—or nTron—, can be patterned from a single thin film of superconducting material with conventional electron-beam lithography. The nanocryotron has a demonstrated gain of >20, can drive impedances of 100 kΩ, and operates in typical ambient magnetic fields.


The team has additionally applied it both as a digital logic element in a half-adder circuit, and as a digital amplifier for superconducting nanowire single-photon detectors pulses. The nanocryotron has immediate applications in classical and quantum communications, photon sensing, and astronomy, and its input characteristics are suitable for integration with existing superconducting technologies.

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Brain barrier opened for first time to treat cancer

Brain barrier opened for first time to treat cancer | Amazing Science | Scoop.it

For the first time, doctors have opened and closed the brain's protector – the blood-brain barrier – on demand. The breakthrough will allow drugs to reach diseased areas of the brain that are otherwise out of bounds. Ultimately, it could make it easier to treat conditions such as Alzheimer's and brain cancer.


The blood-brain barrier (BBB) is a sheath of cells that wraps around blood vessels (in black) throughout the brain. It protects precious brain tissue from toxins in the bloodstream, but it is a major obstacle for treating brain disorders because it also blocks the passage of drugs.


Several teams have opened the barrier in animals to sneak drugs through. Now Michael Canney at Paris-based medical start-up CarThera, and his colleagues have managed it in people using an ultrasound brain implant and an injection of microbubbles.

When ultrasound waves meet microbubbles in the blood, they make the bubbles vibrate. This pushes apart the cells of the BBB.


With surgeon Alexandre Carpentier at Pitié-Salpêtrière Hospital in Paris, Canney tested the approach in people with a recurrence of glioblastoma, the most aggressive type of brain tumour. People with this cancer have surgery to remove the tumours and then chemotherapy drugs, such as Carboplatin, are used to try to kill any remaining tumour cells. Tumours make the BBB leaky, allowing in a tiny amount of chemo drugs: if more could get through, their impact would be greater, says Canney.


The team tested the idea on four patients by implanting an ultrasound transducer through a hole already made in their skulls during tumour-removal surgery. They were then given an injection of microbubbles and had the transducer switched on for 2 minutes. This sent low-intensity pulses of ultrasound into a region of the brain just 10 millimetres by 4 mm. Canney reckons this makes the BBB in this region more permeable for about 6 hours. In this time window, each person received normal chemotherapy.

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Bacteria Make Drug-Like Molecules in Humans: Over 14,000 biosynthetic Gene Clusters for Small Molecules Identified

Bacteria Make Drug-Like Molecules in Humans: Over 14,000 biosynthetic Gene Clusters for Small Molecules Identified | Amazing Science | Scoop.it

Small molecules encoded by biosynthetic gene clusters are widely used in the clinic and constitute much of the chemical language of interspecies interactions. In a recent study, researchers used a systematic approach to identify more than 3,000 small-molecule biosynthetic gene clusters in the genomes of human-associated bacteria. As reported in Cell, they discovered that biosynthetic gene clusters for thiopeptides—a class of antibiotics—are widely distributed in the genomes of the human microbiota.


“This study shows for the first time that our microbiota—the good microbes that live with humans—produce drug-like molecules to protect us from pathogens,” said lead study author Mohamed Donia of the University of California, San Francisco (UCSF). “For a long time, scientists used to go to remote and exotic places to find bacteria that produce novel chemical entities with drug-like properties. Who knew we could find similar ones in our own bodies?”


Donia and his collaborators used an algorithm they recently developed to systematically analyze about 2,400 reference genomes of the human microbiota from various body sites. They detected more than 14,000 biosynthetic gene clusters for a broad range of small-molecule classes. Reasoning that the products of these gene clusters are most likely to mediate conserved microbe-host and microbe-microbe interactions, they set out to identify the subset of gene clusters commonly found in healthy individuals by analyzing 752 metagenomic samples from the National Institutes of Health Human Microbiome Project.


Remarkably, nearly all of these gene clusters had never before been studied or even described, illustrating how little is known about their small-molecule products. “We need to study every single one of these molecules and understand what they are doing,” Donia said. “We have published the list of the small molecule-encoding genes that we identified, and we are reaching out to the scientific community to help us characterize them.”


Thiopeptides are perhaps the most interesting of these molecules because they have potent antibacterial activity against Gram-positive species. Currently, one semisynthetic member of this class is undergoing clinical trials for treating bacterial infections. But according to the authors, no thiopeptide biosynthetic gene cluster or small-molecule product from the human microbiome had ever been experimentally characterized. Surprisingly, their analysis revealed thiopeptide-like biosynthetic gene clusters in isolates from every human body site.


Donia and his collaborators went on to purify and solve the structure of a thiopeptide named lactocillin, which showed potent antibacterial activity against a range of Gram-positive vaginal pathogens. By analyzing human metatranscriptomic sequencing data, they showed that lactocillin and other thiopeptide biosynthetic gene clusters were expressed in vivo, suggesting a potential role in mediating microbe-microbe interactions.

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Geneticist George Church: A Future Without Limits

Geneticist George Church: A Future Without Limits | Amazing Science | Scoop.it

In the future, George Church believes, almost everything will be better because of genetics. If you have a medical problem, your doctor will be able to customize a treatment based on your specific DNA pattern. When you fill up your car, you won't be draining the world's dwindling supply of crude oil, because the fuel will come from microbes that have been genetically altered to produce biofuel. When you visit the zoo, you'll be able to take your children to the woolly mammoth or passenger pigeon exhibits, because these animals will no longer be extinct. You'll be able to do these things, that is, if the future turns out the way Church envisions it—and he's doing everything he can to see that it does.


In 2005 he launched the Personal Genome Project, with the goal of sequencing and sharing the DNA of 100,000 volunteers. With an open-source database of that size, he believes, researchers everywhere will be able to meaningfully pursue the critical task of correlating genetic patterns with physical traits, illnesses, and exposure to environmental factors to find new cures for diseases and to gain basic insights into what makes each of us the way we are. Church, tagged as subject hu43860C, was first in line for testing. Since then, more than 13,000 people in the U.S., Canada, and the U.K. have volunteered to join him, helping to establish what he playfully calls the Facebook of DNA.


Church has made a career of defying the impossible. Propelled by the dizzying speed of technological advancement since then, the Personal Genome Project is just one of Church's many attempts to overcome obstacles standing between him and the future.


"It's not for everyone," he says. "But I see a trend here. Openness has changed since many of us were young. People didn't use to talk about sexuality or cancer in polite society. This is the Facebook generation." If individuals were told which diseases or medical conditions they were genetically predisposed to, they could adjust their behavior accordingly, he reasoned. Although universal testing still isn't practical today, the cost of sequencing an individual genome has dropped dramatically in recent years, from about $7 million in 2007 to as little as $1,000 today.


"It's all too easy to dismiss the future," he says. "People confuse what's impossible today with what's impossible tomorrow.", especially through the emerging discipline of "synthetic" biology. The basic idea behind synthetic biology, he explained, was that natural organisms could be reprogrammed to do things they wouldn't normally do, things that might be useful to people. In pursuit of this, researchers had learned not only how to read the genetic code of organisms but also how to write new code and insert it into organisms. Besides making plastic, microbes altered in this way had produced carpet fibers, treated wastewater, generated electricity, manufactured jet fuel, created hemoglobin, and fabricated new drugs. But this was only the tip of the iceberg, Church wrote. The same technique could also be used on people.


"Every cell in our body, whether it's a bacterial cell or a human cell, has a genome," he says. "You can extract that genome—it's kind of like a linear tape—and you can read it by a variety of methods. Similarly, like a string of letters that you can read, you can also change it. You can write, you can edit it, and then you can put it back in the cell."


This April, the Broad Institute, where Church holds a faculty appointment, was awarded a patent for a new method of genome editing called CRISPR (clustered regularly interspersed short palindromic repeats), which Church says is one of the most effective tools ever developed for synthetic biology. By studying the way that certain bacteria defend themselves against viruses, researchers figured out how to precisely cut DNA at any location on the genome and insert new material there to alter its function. Last month, researchers at MIT announced they had used CRISPR to cure mice of a rare liver disease that also afflicts humans. At the same time, researchers at Virginia Tech said they were experimenting on plants with CRISPR to control salt tolerance, improve crop yield, and create resistance to pathogens.


The possibilities for CRISPR technology seem almost limitless, Church says. If researchers have stored a genetic sequence in a computer, they can order a robot to produce a piece of DNA from the data. That piece can then be put into a cell to change the genome. Church believes that CRISPR is so promising that last year he co-founded a genome-editing company, Editas, to develop drugs for currently incurable diseases.

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First 3D map of the cosmic web at a distance of 10.8 billion light years from Earth

First 3D map of the cosmic web at a distance of 10.8 billion light years from Earth | Amazing Science | Scoop.it

A team led by astronomers from the Max Planck Institute for Astronomy has created the first three-dimensional map of the 'adolescent' Universe, just 3 billion years after the Big Bang. This map, built from data collected from the W. M. Keck Observatory, is millions of light-years across and provides a tantalizing glimpse of large structures in the 'cosmic web' – the backbone of cosmic structure.


On the largest scales, matter in the Universe is arranged in a vast network of filamentary structures known as the 'cosmic web', its tangled strands spanning hundreds of millions of light-years. Dark matter, which emits no light, forms the backbone of this web, which is also suffused with primordial hydrogen gas left over from the Big Bang. Galaxies like our own Milky Way are embedded inside this web, but fill only a tiny fraction of its volume.


Now a team of astronomers led by Khee-Gan Lee, a post-doc at the Max Planck Institute for Astronomy, has created a map of hydrogen absorption revealing a three-dimensional section of the universe 11 billions light years away – the first time the cosmic web has been mapped at such a vast distance. Since observing to such immense distances is also looking back in time, the map reveals the early stages of cosmic structure formation when the Universe was only a quarter of its current age, during an era when the galaxies were undergoing a major 'growth spurt'.


The map was created by using faint background galaxies as light sources, against which gas could be seen by the characteristic absorption features of hydrogen. The wavelengths of each hydrogen feature showed the presence of gas at a specific distance from us. Combining all of the measurements across the entire field of view allowed the team a tantalizing glimpse of giant filamentary structures extending across millions of light-years, and paves the way for more extensive studies that will reveal not only the structure of the cosmic web, but also details of its function – the ways that pristine gas is funneled along the web into galaxies, providing the raw material for the formation of galaxies, stars, and planets.

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First large DNA crystals generated which could create revolutionary nanodevices

First large DNA crystals generated which could create revolutionary nanodevices | Amazing Science | Scoop.it

DNA has garnered attention for its potential as a programmable material platform that could spawn entire new and revolutionary nanodevices in computer science, microscopy, biology, and more. Researchers have been working to master the ability to coax DNA molecules to self assemble into the precise shapes and sizes needed in order to fully realize these nanotechnology dreams.


For the last 20 years, scientists have tried to design large DNA crystals with precisely prescribed depth and complex features — a design quest just fulfilled by a team at Harvard's Wyss Institute for Biologically Inspired Engineering. The team built 32 DNA crystals with precisely–defined depth and an assortment of sophisticated three–dimensional (3D) features, an advance reported in Nature Chemistry.


The team used their "DNA–brick self–assembly" method, which was first unveiled in a 2012 Science publication when they created more than 100 3D complex nanostructures about the size of viruses. The newly–achieved periodic crystal structures are more than 1000 times larger than those discrete DNA brick structures, sizing up closer to a speck of dust, which is actually quite large in the world of DNA nanotechnology.


"We are very pleased that our DNA brick approach has solved this challenge," said senior author and Wyss Institute Core Faculty member Peng Yin, Ph.D., who is also an Associate Professor of Systems Biology at Harvard Medical School, "and we were actually surprised by how well it works."


Scientists have struggled to crystallize complex 3D DNA nanostructures using more conventional self–assembly methods. The risk of error tends to increase with the complexity of the structural repeating units and the size of the DNA crystal to be assembled.


The DNA brick method uses short, synthetic strands of DNA that work like interlocking Lego® bricks to build complex structures. Structures are first designed using a computer model of a molecular cube, which becomes a master canvas. Each brick is added or removed independently from the 3D master canvas to arrive at the desired shape — and then the design is put into action: the DNA strands that would match up to achieve the desired structure are mixed together and self assemble to achieve the designed crystal structures.


"Therein lies the key distinguishing feature of our design strategy–its modularity," said co–lead author Yonggang Ke, Ph.D., formerly a Wyss Institute Postdoctoral Fellow and now an assistant professor at the Georgia Institute of Technology and Emory University. "The ability to simply add or remove pieces from the master canvas makes it easy to create virtually any design."


The modularity also makes it relatively easy to precisely define the crystal depth. "This is the first time anyone has demonstrated the ability to rationally design crystal depth with nanometer precision, up to 80 nm in this study," Ke said. In contrast, previous two–dimensional DNA lattices are typically single–layer structures with only 2 nm depth.


"DNA crystals are attractive for nanotechnology applications because they are comprised of repeating structural units that provide an ideal template for scalable design features", said co–lead author graduate student Luvena Ong.


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A tiny ultrasound-powered chip to serve as medical device

A tiny ultrasound-powered chip to serve as medical device | Amazing Science | Scoop.it

Stanford engineers are developing a way to send power — safely and wirelessly — to “smart chips” in the body that are programmed to perform medical tasks and report back the results. The idea is to get rid of wires and batteries, which would make the implant too big or clumsy.


Their approach involves beaming ultrasound at a tiny device inside the body designed to do three things: convert the incoming sound waves into electricity; process and execute medical commands; and report the completed activity via a tiny built-in radio antenna.


“We think this will enable researchers to develop a new generation of tiny implants designed for a wide array of medical applications,” said Amin Arbabian, an assistant professor of electrical engineering at Stanford.

Arbabian’s team recently presented a working prototype of this wireless medical implant system at the IEEE Custom Integrated Circuits Conference in San Jose.


The researchers chose ultrasound to deliver wireless power to their medical implants because it has been safely used in many applications, such as fetal imaging, and can provide precision and sufficient power  to implants a millimeter or less in size. Arbabian and his colleagues are collaborating with other researchers to develop sound-powered implants for a variety of medical applications, from studying the nervous system to treating the symptoms of Parkinson’s disease.


The Stanford medical implant chip is powered by piezoelectricity (pressure on a material generates an electric voltage). The Stanford team created pressure by aiming ultrasound waves at a tiny piece of piezoelectric material mounted on the device.


In the future, the team plans to extend the capabilities of the implant chip to perform medical tasks, such as powering sensors or delivering therapeutic jolts of electricity right where a patient feels pain.


References:


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World first: Man paralyzed from the chest down walks again after cell transplant from his nasal cavity

World first: Man paralyzed from the chest down walks again after cell transplant from his nasal cavity | Amazing Science | Scoop.it

A paralysed man has been able to walk again after a pioneering therapy that involved transplanting cells from his nasal cavity into his spinal cord. Darek Fidyka, who was paralyzed from the chest down in a knife attack in 2010, can now walk using a frame. The treatment, a world first, was carried out by surgeons in Poland in collaboration with scientists in London.


Details of the research are published in the journal Cell TransplantationBBC One's Panorama program had unique access to the project and spent a year charting the patient's rehabilitation. Darek Fidyka, 40, from Poland, was paralyzed after being stabbed repeatedly in the back in the 2010 attack. He said walking again - with the support of a frame - was "an incredible feeling", adding: "When you can't feel almost half your body, you are helpless, but when it starts coming back it's like you were born again."


Prof Geoff Raisman, chair of neural regeneration at University College London's Institute of Neurology, led the UK research team. He said what had been achieved was "more impressive than man walking on the moon".


The treatment used olfactory ensheathing cells (OECs) - specialist cells that form part of the sense of smell. OECs act as pathway cells that enable nerve fibers in the olfactory system to be continually renewed. In the first of two operations, surgeons removed one of the patient's olfactory bulbs and grew the cells in culture. Two weeks later they transplanted the OECs into the spinal cord, which had been cut through in the knife attack apart from a thin strip of scar tissue on the right. They had just a drop of material to work with - about 500,000 cells. About 100 micro-injections of OECs were made above and below the injury.


Four thin strips of nerve tissue were taken from the patient's ankle and placed across an 8mm (0.3in) gap on the left side of the cord.

The scientists believe the OECs provided a pathway to enable fibers above and below the injury to reconnect, using the nerve grafts to bridge the gap in the cord.

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Inactivation of the human papillomavirus E6 or E7 gene in cervical carcinoma cells using a bacterial CRISPR/Cas

Inactivation of the human papillomavirus E6 or E7 gene in cervical carcinoma cells using a bacterial CRISPR/Cas | Amazing Science | Scoop.it

Researchers have hijacked a defense system normally used by bacteria to fend off viral infections and redirected it against the human papillomavirus (HPV), the virus that causes cervical, head and neck, and other cancers.

Using the genome editing tool known as CRISPR, the Duke University researchers were able to selectively destroy two viral genes responsible for the growth and survival of cervical carcinoma cells, causing the cancer cells to self-destruct.

The findings, published in the Journal of Virology, give credence to an approach only recently attempted in mammalian cells, and could pave the way toward antiviral strategies targeted against other DNA-based viruses like hepatitis B and herpes simplex. 


"Because this approach is only going after viral genes, there should be no off-target effects on normal cells," said Bryan R. Cullen, Ph.D., senior study author and professor of molecular genetics and microbiology at Duke University School of Medicine. "You can think of this as targeting a missile that will destroy a certain target. You put in a code that tells the missile exactly what to hit, and it will only hit that, and it won't hit anything else because it doesn't have the code for another target."


In this study, Cullen decided to target the human papillomavirus (HPV), which causes almost all cervical cancers and about half of head and neck cancers. Specifically, he and his colleagues went after the viral genes E6 and E7, two "oncogenes" that block the host's own efforts to keep cancer cells at bay.


To run CRISPR against the virus, the researchers needed two ingredients. First, they needed the target code for E6 or E7, consisting of a short strip of RNA sequence, the chemical cousin of DNA. To this "guide RNA" they added the Cas9 protein, which would cut any DNA that could line up and bind to that RNA sequence.

The carcinoma cells that received the anti-HPV guide RNA/Cas9 combination immediately stopped growing. In contrast, cells that had received a control virus, containing a random guide RNA sequence, continued on their path to immortality. The researchers then dug down to the molecular level to investigate the consequences of destroying E6 or E7 in cancer cells. E6 normally blocks a protein called p53, known as the guardian of the genome because it can turn on suicide pathways in the cell when it senses that something has gone awry. In this study, targeting E6 enabled p53 to resume its normal function, spurring death of the cancer cell.


E7 works in a similar way, blocking another protein called retinoblastoma or Rb that can trigger growth arrest and senescence, another form of cell death. As expected, the researchers found that targeting E7 also set this second "tumor suppressor" back in motion.


"As soon as you turn off E6 or E7, the host defense mechanisms are allowed to come back on again, because they have been there this whole time, but they have been turned off by HPV," Cullen said. "What happens is the cell immediately commits suicide."


Cullen and his colleagues are now working on developing a different viral vector, based on the adeno-associated virus, to deliver their CRISPR cargo into cancer cells. Once they are happy with their delivery system, they will begin to test this approach in animal models.


"What we would hope to see in an HPV-induced cancer is rapid induction of tumor necrosis caused by loss of E6 or E7," Cullen said. "This method has the potential to be a single hit treatment that will dramatically reduce tumor load without having any effect on normal cells."


The researchers are also targeting other viruses that use DNA as their genetic material, including the hepatitis B virus and herpes simplex virus.


Reference: "Inactivation of the human papillomavirus E6 or E7 gene in cervical carcinoma cells using a bacterial CRISPR/Cas RNA-guided endonuclease," Edward M. Kennedy, Anand V. R. Kornepati, Michael Goldstein, Hal P. Bogerd, Brigid C. Poling, Adam W. Whisnant, Michael B. Kastan and Bryan R. Cullen.Journal of Virology, August 6, 2014. DOI 10.1128/JVI.01879-14.

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Far-Out Concepts NASA Selects For Funding

Far-Out Concepts NASA Selects For Funding | Amazing Science | Scoop.it

Sometimes a good idea takes some tinkering. You have a thought that it will work, but what it really requires is you take some money and time and test it out in a small form. This principle is sound if you’re trying to do home renovation (a paint splash on a wall can let you see if the color will work) and it is especially true if you’re planning a multi-million dollar mission to another planet.


This is the thought behind the NASA Innovative Advanced Concepts office, which announced a dozen far-flung drawing-board proposals that received $100,000 in Phase 1 funding for the next 9-12 months. There are vehicles to explore the soupy moon of Titan, a design to snag a tumbling asteroid, and other ideas to explore the solar system. But be patient: These testbed ideas would take decades to come to fruition, if they are even accepted for further study and funding.


Titan Aerial Daughtercraft: A small rotorcraft that can touch down from a balloon or lander.


Titan SubmarineA small submarine would dive into Kraken Mare on Saturn’s moon, and there would be plenty to explore: 984 feet (300 meters) of depth, stretching across 621 miles (1,000 km). 


Comet Hitchhiker: This would be a “tethered” spacecraft that swings from comet to comet to explore icy bodies in the solar system.


Weightless Rendezvous And Net Grapple to Limit Excess Rotation: This idea would capture space debris and small asteroids.


The Aragoscope: A telescope that would look through an opaque disk at a distant object, which is different from the usual mirror arrangement.


Mars Ecopoiesis Test Bed: A machine that would test how well bacteria from Earth could survive on Mars, which could be a precursor to “terraforming” the planet to make it more like our own.


ChipSats: Instead of having an orbiter and a lander in separate missions, why not put them in one?


Swarm Flyby Gravimetry: While whizzing by a comet or asteroid, a single spacecraft would release a swarm of tiny probes.


Probing icy worlds concept: How thick is the ice on Jupiter’s Europa or Ganymede, or Saturn’s Enceladus?


Heliopause Electrostatic Rapid Transit System (HERTS): This would be a mission that goes deep into the solar-system and out to the heliopause, the spot where the sun’s sphere of influence gives way to the interstellar medium.


3D Photocatalytic Air Processor: A new design to make it easier to generate oxygen on a spacecraft, using “abundant high-energy light in space,” the proposal states.


PERIapsis Subsurface Cave OPtical Explorer (PERISCOPE)A way to probe caves on the moon from orbit. Using a concept called “photon time-of-flight imaging”, the researchers say they would be able to bounce the signal off of the walls of the canyon to peer into the crevice and see what is there.

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Alcoholism linked to lack of intestinal bacteria

Alcoholism linked to lack of intestinal bacteria | Amazing Science | Scoop.it

A new study suggests that bacteria in the gut may play a role in alcohol addiction and the risk of relapse after rehab. "Our results provides strong evidence that alcohol addiction is not only in the brain, but that it in some cases can be associated with an imbalance in the intestinal flora,” said Professor Fredrik Bäckhed from the University of Gothenburg during a guest lecture at Novo Nordisk Foundation Center for Basic Metabolic Research at Copenhagen University.


Alcohol dependence has traditionally been considered a brain disorder. Alteration in the composition of the gut microbiota has recently been shown to be present in psychiatric disorders, which suggests the possibility of gut-to-brain interactions in the development of alcohol dependence. The aim of a recent study was to explore whether changes in gut permeability are linked to gut-microbiota composition and activity in alcohol-dependent subjects. The researchers also investigated whether gut dysfunction is associated with the psychological symptoms of alcohol dependence. Additionally, they tested the reversibility of the biological and behavioral parameters after a short-term detoxification program. The study found that some, but not all, alcohol-dependent subjects developed gut leakiness, which was associated with higher scores of depression, anxiety, and alcohol craving after 3 weeks of abstinence, which may be important psychological factors of relapse. Moreover, subjects with increased gut permeability also had altered composition and activity of the gut microbiota. These results suggest the existence of a gut–brain axis in alcohol dependence, which implicates the gut microbiota as an actor in the gut barrier and in behavioral disorders. Thus, the gut microbiota seems to be a previously unidentified target in the management of alcohol dependence.

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Madagascar's bark spider (Caerostris darwini) makes up to 82 feet large orb nets, 10 x stronger than Kevlar

Madagascar's bark spider (Caerostris darwini) makes up to 82 feet large orb nets, 10 x stronger than Kevlar | Amazing Science | Scoop.it

The web of the Darwin's bark spider (Caerostris darwini), can span some square feet (2.8 square meters) and is attached to each riverbank by anchor threads as long as 82 feet (25 meters).


Scientists have found the toughest material made by life yet — the silk of a spider whose giant webs span rivers, streams and even lakes. Spider silks were already the toughest known biomaterials, able to absorb massive amounts of energy before breaking. However, researchers have now revealed the Darwin's bark spider (Caerostris darwini) has the toughest silk ever seen — more than twice as tough as any previously described silk, and more than 10 times stronger than Kevlar.


Although scientists have investigated silks from 20-to-30 species of spiders before, most of these were chosen haphazardly — for instance, from researchers' backyards. There are over 40,000 species of spiders and each spider can produce up to seven different kinds of silk. Thus, more than 99.99 percent of spider silks are yet to be explored.

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What Happens After Someone Survives Ebola?

What Happens After Someone Survives Ebola? | Amazing Science | Scoop.it

While most of the recent coverage of the ongoing Ebola outbreak has focused on rising death tolls and a few infected U.S. citizens, other segments of the population have passed mostly unnoticed from the harsh glare of the media spotlight: Survivors, and those who are seemingly immune to Ebola.


People who survive Ebola can lead normal lives post-recovery, though occasionally they can suffer inflammatory conditions of the joints afterwards, according to CBS. Recovery times can vary, and so can the amount of time it takes for the virus to clear out of the system.


The World Health Organization found that the virus can reside in semen for up to seven weeks after recovery. Survivors are generally assumed to be immune to the particular strain they are infected by, and are able to help tend to others infected with the same strain. What isn't clear is whether or not a person is immune to other strains of Ebola, or if their immunity will last.


As with most viral infections, patients who recover from Ebola end up with Ebola-fighting antibodies in their blood, making their blood a valuable (if controversial) treatment option for others who catch the infection. Kent Brantly, one of the most recognizable Ebola survivors, has donated more than a gallon of his blood to other patients. The plasma of his blood, which contains the antibodies, is separated out from the red blood cells, creating what’s known as a convalescent serum, which can then be given to a patient as a transfusion. The hope is that the antibodies in the serum will boost the patient’s immune response, attacking the virus, and allowing the body to recover.


But this treatment method, like all Ebola treatment methods, is far from ideal. To start with, scientists aren't even sure if it works. In addition, the serum can only be donated to people with a compatible blood type to the donor, and it’s unclear how long the immunity would last. Adding to the confusion, there are several different strains of Ebola, and there’s no guarantee that once someone has recovered from one strain of Ebola they are immune to others.


When Nancy Writebol, one of the survivors of Ebola who was whisked back to Atlanta soon after contracting the virus, was asked by Science Magazine if she would consider going back, she said: “I’ve done some reading on that and talked to doctors at Emory about that. My doctors at Emory are not sure how long immunity would last. It’s not been studied. I’ve read that even if a survivor was willing and able to help with the care for Ebola patients, because there are so many strains of Ebola, it would still be very wise and necessary to operate in PPEs and not just assume you’re immune.”


People who survived the disease are of particular interest to researchers, such as those working on the ZMapp drug, who hope that they can synthesize antibodies in the hopes of creating a cure.


But even less understood than the survivors are the people who were infected with Ebola but never developed any symptoms. After outbreaks in Uganda in the late 1990’s, scientists tested the blood of several people who were in close contact with Ebola patients, and found a number of them had markers in their blood indicating they carried the disease, but they were totally asymptomatic—they managed to completely avoid the horrifying symptoms of the disease.


In a letter in the Lancet this week, researchers look into the existence of these asymptomatic patients, and hope that identifying people who are naturally immune could help contain the outbreak as scientists work on developing a treatment. A 2010 study published by the French research organization IRD found that as much as 15.3 percent of Gabon's population could be immune to Ebola.

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Plasma bombs, powerful tornadoes, and supersonic jets may be the start of the solar wind.

Plasma bombs, powerful tornadoes, and supersonic jets may be the start of the solar wind. | Amazing Science | Scoop.it

The first detailed view of a poorly understood region of the Sun reveals plasma 'bombs', powerful tornadoes, and supersonic jets that may be the start of the solar wind. These observations, reported in five papers in the journalScience, will help scientists determine how massive amounts of energy generated by the Sun are transported from its surface to its outer atmosphere.


The features were detected by NASA's new IRIS space telescope, which studies the mysterious interface region that sits between the Sun's surface (photosphere) and the outer atmosphere (corona).


"IRIS's findings tell us the interface region of the Sun is far more complicated than we imagined," says Dr Hui Tian of the Harvard-Smithsonian Centre for Astrophysics, who is an author on four of the papers. The interface region is composed of the chromosphere and a transition layer between the chromospheres and corona.


"It's not the thin static layer predicted in solar atmospheric models. There's a sharp temperature change from the 6000-degree photosphere to the corona where temperatures reach over a million degrees, and the interface region is where this change occurs," says Tian. The region emits mostly ultraviolet light, which can be best studied in high resolution detail from space.


Using imaging and spectrometry, IRIS traces temperature differences within the chromosphere, as well as the speed, density and turbulence of dynamic plasma particles.


Tian and colleagues used IRIS to observe activity inside coronal holes where they discovered high-speed jets that may contribute plasma to the solar wind, the stream of particles constantly flowing from the Sun, which generates space weather on Earth.

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