爱上海,上海419论坛,上海龙凤419 – Powered by Brooklynn Wilbert!

Archives for: August 31, 2019

Toshiba Introduces New 10 YearQuick Charge Industrial Battery

Posted on by

first_img Citation: Toshiba Introduces New 10 Year–Quick Charge Industrial Battery (2007, December 11) retrieved 18 August 2019 from https://phys.org/news/2007-12-toshiba-year-quick-industrial-battery.html Toshiba has developed a battery that can be recharged in five minutes with a lifespan of 10 years. Toshiba has trademarked the new accumulator, the SCiB. The new quick charge-Super Charge ion Battery will go to market in March, 2008. Initially, the SCiB distribution will focus on the industrial equipment sector. In practical use of the new SCiB its unique composition allows for 4.2 Ah, (ampere hours) on 10 cells for recharging by standard or alternative energy sources. The monitoring system within the battery controls voltage temperature, and cell balance adjustments. This safety precaution minimizes or eliminates the possibility of short circuits or explosions by ignition within the battery. In an industrial setting, the safety precautions features alone sell the product. The SCiB may be recharged in as little as five minutes time. The unique feature of the new product is that after 3,000 recharges the battery only lost less than 10 percent efficiency. In further company tests after 5,000 recharges the SCiB was still viable. This amounts to 10 years of continuous use for the SCiB. This feature reduces the need for battery waste management, by extending the use of the battery. The battery´s longevity and versatility in utilizing energy sources qualify it as a Green Technology. The standard or SCiB mode features extensive safety precaution for high power charges. The battery may be charged to 90 percent or more in five minutes. Other batteries do not have the same level of safety built-in that will allow heavy current charges, (50A). This feature suits the industrial setting in providing quick charges without the obvious hazards of fire and explosions. An additional feature of the SCiB is its ability to run at extremely cold temperatures. Toshiba warrants that the SCiB can work efficiently in minus 30 C which is minus 22 F. This is a welcomed attraction for many areas of the world where frigid temperatures are a factor. Toshiba has not released details on when it will be released to a broader sector of the market. In addition, the company has not indicated the various modifications they may be considering for future development. Super Charge ion Battery. Credit: Toshiba Explore further This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Toshiba will begin selling the SCiB quick charge-10 year battery in March, 2008. This industrial battery increases safety, versatility in power source and qualifies as environmentally sensitive. Toshiba’s SCiB rechargeable battery selected for new electric vehicleslast_img read more

Tagged: , , , , , , , , , , , .

Anthropologist Says Tree Climbing Abilities of Early Hominins Decreased Rapidly in Evolutionary

Posted on by

first_img Most human evolution researchers agree that at some point in history, estimated to be about 5 million to 7 million years ago the chimpanzee and human like species proceeded on a different evolutionary path. The question DeSilva addresses is whether early man’s adaptation to full bipedalism involved a swift shedding of the ability to climb and swing from trees. DeSilva compared the great apes and early hominin ankle joint, the tibia and the talus in the foot. He discovered marked differences between the structure and capacity of these two skeletal fossils. DeSilva observed and filmed Uganda’s modern chimps tree climbing and tree swinging activity. He discovered that modern chimpanzees when pushing off from a tree branch flex their ankles, thereby raising their foot some 45 degrees. Modern man generally flexes his ankle only 15 to 20 degrees while walking and suffers injury if stretched any further. It goes without saying, there are certain super modern athletes who can flex the ankle without injury. In effect, DeSilva points to an important evolutionary divide, wherein early hominin may have foregone his natural tree climbing, ankle flexing capacity in order to walk upright. His examination of early hominin and the great ape indicates the evolutionary morphing took place very rapidly. His review of early hominin and the great ape demonstrate the ankle joint differences took place early in the evolutionary cycle. According to ScienceNow reporter Michael Baiter in his article, “Our Ancestors Were No Swingers”, David Begum, a paleoanthropologist at the University of Toronto in Canada points to early hominins ability to scramble up a tree for safety which would not have involved or required the full 45 degree ankle flex exhibited by modern chimpanzees. The DeSilva study agrees with its critics. He concludes that if early hominins included tree climbing as part of their survival skill set, they were performing it very differently than modern chimpanzees. Sources: PNAS, April 13, 2009, www.pnas.org/content/early/200 … /0900270106.abstract Science Now, April 13, 2009, sciencenow.sciencemag.org/cgi/ … tent/full/2009/413/2© 2009 PhysOrg.com Explore further Jeremy M. DeSilva an anthropologist at Worcester University in Massachusetts has published “Functional Morphology of the Ankle and the Likelihood of Climbing in Early Hominins,” in the peer-reviewed journal, Proceeding of the National Academies of Sciences of the USA current issue. The study includes data gathered by DeSilva in Uganda’s Kibale National Park of modern chimpanzee and comparisons of hominin fossil skeletal remains dating back some 4.12 million to 1.53 million years ago. The findings appear to show that if early hominins depended on tree climbing as part of their survival repertoire, they were performing it decidedly different from modern chimpanzee locomotor activity. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Citation: Anthropologist Says Tree Climbing Abilities of Early Hominins Decreased Rapidly in Evolutionary Process (2009, April 15) retrieved 18 August 2019 from https://phys.org/news/2009-04-anthropologist-tree-climbing-abilities-early.html Early human ancestors had a wobble in their walk Credit: Mongabay.comlast_img read more

Tagged: , , , , , , , , , , , .

The blackbox in your car

Posted on by

first_img © 2010 PhysOrg.com The boxes, which are already used in planes are more commonly know by the name “black box”, and are designed to record the condition of a vehicle and show us the last few seconds of the car before the crash. The device, which the driver would not be able to turn off, would be able to be used by law enforcement, insurance companies and automakers to gather more crash data.There are some concerns about the use of the data, and the potential overreach of government authority, but this may not stop the mandate from going through. If you have an airbag in your car then the odds are that you already have one of these devices in your car, but the information that you will get about the device will probably come completely from the legal disclosure in your owner’s manual.This new mandate may conflict with the laws of some states that prohibit the disclosure of this particular type of data. Though, the odds are that you do not live in one of those states that has these data protection laws. There are 37 states with no laws that bar the disclosure of this type of data. Currently, there are no federal laws that explicitly govern the access to this black box data, or any laws that clarify how much of this driving data other parties, such as your insurance company, can legally access. (PhysOrg.com) — It is expected that within the next month officials at the National Highway Traffic Safety Administration will declare that all cars must have an event data recorder inside the vehicle. Study: distracted driving laws don’t stop crashes This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. via Wired More information: Citation: The blackbox in your car (2011, May 24) retrieved 18 August 2019 from https://phys.org/news/2011-05-blackbox-car.html Explore furtherlast_img read more

Tagged: , , , , , , , , , , , .

Is mathematics an effective way to describe the world

Posted on by

first_imgMath has the illusion of being effective when we focus on the successful examples, Abbott argues. But there are many more cases where math is ineffective than where it is effective. Credit: Derek Abbott. ©2013 IEEE Explore further © 2013 Phys.org Citation: Is mathematics an effective way to describe the world? (2013, September 3) retrieved 18 August 2019 from https://phys.org/news/2013-09-mathematics-effective-world.html Mathematics has been called the language of the universe. Scientists and engineers often speak of the elegance of mathematics when describing physical reality, citing examples such as π, E=mc2, and even something as simple as using abstract integers to count real-world objects. Yet while these examples demonstrate how useful math can be for us, does it mean that the physical world naturally follows the rules of mathematics as its “mother tongue,” and that this mathematics has its own existence that is out there waiting to be discovered? This point of view on the nature of the relationship between mathematics and the physical world is called Platonism, but not everyone agrees with it. Derek Abbott, Professor of Electrical and Electronics Engineering at The University of Adelaide in Australia, has written a perspective piece to be published in the Proceedings of the IEEE in which he argues that mathematical Platonism is an inaccurate view of reality. Instead, he argues for the opposing viewpoint, the non-Platonist notion that mathematics is a product of the human imagination that we tailor to describe reality. This argument is not new. In fact, Abbott estimates (through his own experiences, in an admittedly non-scientific survey) that while 80% of mathematicians lean toward a Platonist view, engineers by and large are non-Platonist. Physicists tend to be “closeted non-Platonists,” he says, meaning they often appear Platonist in public. But when pressed in private, he says he can “often extract a non-Platonist confession.”So if mathematicians, engineers, and physicists can all manage to perform their work despite differences in opinion on this philosophical subject, why does the true nature of mathematics in its relation to the physical world really matter? The reason, Abbott says, is that because when you recognize that math is just a mental construct—just an approximation of reality that has its frailties and limitations and that will break down at some point because perfect mathematical forms do not exist in the physical universe—then you can see how ineffective math is. And that is Abbott’s main point (and most controversial one): that mathematics is not exceptionally good at describing reality, and definitely not the “miracle” that some scientists have marveled at. Einstein, a mathematical non-Platonist, was one scientist who marveled at the power of mathematics. He asked, “How can it be that mathematics, being after all a product of human thought which is independent of experience, is so admirably appropriate to the objects of reality?” In 1959, the physicist and mathematician Eugene Wigner described this problem as “the unreasonable effectiveness of mathematics.” In response, Abbott’s paper is called “The Reasonable Ineffectiveness of Mathematics.” Both viewpoints are based on the non-Platonist idea that math is a human invention. But whereas Wigner and Einstein might be considered mathematical optimists who noticed all the ways that mathematics closely describes reality, Abbott pessimistically points out that these mathematical models almost always fall short. What exactly does “effective mathematics” look like? Abbott explains that effective mathematics provides compact, idealized representations of the inherently noisy physical world.”Analytical mathematical expressions are a way making compact descriptions of our observations,” he told Phys.org. “As humans, we search for this ‘compression’ that math gives us because we have limited brain power. Maths is effective when it delivers simple, compact expressions that we can apply with regularity to many situations. It is ineffective when it fails to deliver that elegant compactness. It is that compactness that makes it useful/practical … if we can get that compression without sacrificing too much precision.”I argue that there are many more cases where math is ineffective (non-compact) than when it is effective (compact). Math only has the illusion of being effective when we focus on the successful examples. But our successful examples perhaps only apply to a tiny portion of all the possible questions we could ask about the universe.”Some of the arguments in Abbott’s paper are based on the ideas of the mathematician Richard W. Hamming, who in 1980 identified four reasons why mathematics should not be as effective as it seems. Although Hamming resigned himself to the idea that mathematics is unreasonably effective, Abbott shows that Hamming’s reasons actually support non-Platonism given a reduced level of mathematical effectiveness.Here are a few of Abbott’s reasons for why mathematics is reasonably ineffective, which are largely based on the non-Platonist viewpoint that math is a human invention:• Mathematics appears to be successful because we cherry-pick the problems for which we have found a way to apply mathematics. There have likely been millions of failed mathematical models, but nobody pays attention to them. (“A genius,” Abbott writes, “is merely one who has a great idea, but has the common sense to keep quiet about his other thousand insane thoughts.”)• Our application of mathematics changes at different scales. For example, in the 1970s when transistor lengths were on the order of micrometers, engineers could describe transistor behavior using elegant equations. Today’s submicrometer transistors involve complicated effects that the earlier models neglected, so engineers have turned to computer simulation software to model smaller transistors. A more effective formula would describe transistors at all scales, but such a compact formula does not exist.• Although our models appear to apply to all timescales, we perhaps create descriptions biased by the length of our human lifespans. For example, we see the Sun as an energy source for our planet, but if the human lifespan were as long as the universe, perhaps the Sun would appear to be a short-lived fluctuation that rapidly brings our planet into thermal equilibrium with itself as it “blasts” into a red giant. From this perspective, the Earth is not extracting useful net energy from the Sun.• Even counting has its limits. When counting bananas, for example, at some point the number of bananas will be so large that the gravitational pull of all the bananas draws them into a black hole. At some point, we can no longer rely on numbers to count.• And what about the concept of integers in the first place? That is, where does one banana end and the next begin? While we think we know visually, we do not have a formal mathematical definition. To take this to its logical extreme, if humans were not solid but gaseous and lived in the clouds, counting discrete objects would not be so obvious. Thus axioms based on the notion of simple counting are not innate to our universe, but are a human construct. There is then no guarantee that the mathematical descriptions we create will be universally applicable.For Abbott, these points and many others that he makes in his paper show that mathematics is not a miraculous discovery that fits reality with incomprehensible regularity. In the end, mathematics is a human invention that is useful, limited, and works about as well as expected.For those who seek something more practical out of such a discussion, Abbott explains that this understanding can allow for greater freedom of thought. One example is an improvement of vector operations. The current method involves dot and cross products, “a rather clunky” tool that does not generalize to higher dimensions. Lately there has been a renewed interest in an alternative approach called geometric algebra, which overcomes many of the limitations of dot and cross products and can be extended to higher dimensions. Abbott is currently working on a tutorial paper on geometric algebra for electrical engineers to be published in the near future. Journal information: Proceedings of the IEEE Belgian wins Norway’s $1 million Abel math prize More information: More information: Derek Abbott. “The Reasonable Ineffectiveness of Mathematics.” Proceedings of the IEEE. To be published. DOI: 10.1109/JPROC.2013.2274907 This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

Tagged: , , , , , , , , , , , .

Scientists fabricate defectfree graphene set record reversible capacity for Co3O4 anode in

Posted on by

first_imgSteps to fabricate defect-free graphene: (a) graphite, (b) potassium graphite intercalation compound, (c) graphene nanosheet, and (d) defect-free graphene. Digital images of (e) potassium graphite, (f) a graphene nanosheet, and (g) defect-free graphene. (h) SEM images of (left) a graphene nanosheet and (right) defect-free graphene. (i) and (j) compare X-ray diffraction patterns and Raman spectroscopy of the materials in (a-d). Credit: Park, et al. ©2014 American Chemical Society Journal information: Nano Letters The research groups of Professor Junk-Ki Park and Professor Hee-Tak Kim from Korea Advanced Institute of Science and Technology (KAIST) and Professor Yong-Min Lee’s research group from Hanbat National University, all in Daejeon, South Korea, have published their paper on the new fabrication method in a recent issue of Nano Letters.As the researchers explain, current methods to fabricate high-quality graphene fall into two categories: mechanical approaches and chemical approaches. While mechanical cleavage provides high-quality graphene, its low yield makes it insufficient for large-scale production. Chemical approaches, on the other hand, can produce bulk quantities but can involve imperfections. The new method differs from both of these types of methods and involves a few key steps. First the researchers filled a Pyrex tube with graphite powder, and then placed the open-ended tube inside a slightly larger tube. Then they added potassium to the bottom gap between the two tubes, sealed the tubes, and heated them. The heat causes the molten potassium to move inside the micropores between the graphite powders, so that the potassium molecules become intercalated into the graphite interlayers. The resulting potassium graphite compounds were then placed in a pyridine solution, which causes the layers to expand away from each other to form graphene nanosheets that could later be cooled and exfoliated one layer at a time. The researchers performed many sets of experiments in which they varied factors such as the temperatures and the type of solution, which are critical to control the quality and size of the df-G. They found that, by controlling the temperature of the exfoliation step, the size of the df-G can be varied between 0.25 to 14.0 µm2. The researchers demonstrated that wrapping a large-sized negatively charged sheet of df-G around a positively charged piece of Co3O4 creates an anode with several impressive characteristics. Most significantly is its high capacity after many cycles (1050 mAh/g at 500 mA/g and 900 mAh/g at 1000 mAh/g even after 200 cycles). To the best of the researchers’ knowledge, this reversible capacity is the highest among all Co3O4 electrodes ever reported. The researchers explain that the large-sized df-G, with its perfect crystallinity, improves the anode performance because when a single graphene sheet is wrapped around a bundle of Co3O4 particles, the Co3O4 particles are prevented from becoming pulverized and then electrically detaching from the anode, which would otherwise occur. Because of this protective effect, the anode’s capacity is preserved even after 200 cycles, whereas anodes with an imperfect graphene layer rapidly decrease with cycling. The large size of the graphene plays a key role in the performance because a larger size provides a higher cycling stability of the nanosized anode materials by improving their mechanical integrity.With these advantages, the researchers expect the df-G to bring significant advances of composite electrodes for a variety of electrochemical system, including batteries, fuel cells, and capacitors. More information: Kwang Hyun Park, et al. “Defect-Free, Size-Tunable Graphene for High-Performance Lithium Ion Battery.” Nano Letters. DOI: 10.1021/nl500993q Researchers developing cheap, better-performing lithium-ion batteries Explore furthercenter_img (Phys.org) —Graphene has already been demonstrated to be useful in Li-ion batteries, despite the fact that the graphene used often contains defects. Large-scale fabrication of graphene that is chemically pure, structurally uniform, and size-tunable for battery applications has so far remained elusive. Now in a new study, scientists have developed a method to fabricate defect-free graphene (df-G) without any trace of structural damage. Wrapping a large sheet of negatively charged df-G around a positively charged Co3O4 creates a very promising anode for high-performance Li-ion batteries. © 2014 Phys.org This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Citation: Scientists fabricate defect-free graphene, set record reversible capacity for Co3O4 anode in Li-ion batteries (2014, August 22) retrieved 18 August 2019 from https://phys.org/news/2014-08-scientists-fabricate-defect-free-graphene-reversible.htmllast_img read more

Tagged: , , , , , , , , , , , .

Nanocontainers for nanocargo Delivering genes and proteins for cellular imaging genetic medicine

Posted on by

first_imgIn their paper, the authors report that the T4 capsid NP gene expression and protein delivery system may be complementary to or used in conjunction with gene therapy based on RNA Cas and taran nuclease. (Cas genes code for proteins related to DNA loci containing short repetitions of base sequences known as Clustered Regularly Interspaced Short Palindromic Repeats, or CRISPRs.) “The T4 nanoparticle expression system can easily complement Cas9 and taran nuclease-based recombination by packaging the linear cas9, target-sgRNA plasmid DNA, and Cre recombinase – or even ligase, an enzyme that facilitates the joining of DNA strands – and deliver the resulting T4 nanoparticles into the recipient eukaryotic cells with high specificity employing SOC and HOC,” Liu tells Phys.org. (SOC and HOC are dispensable T4 capsid proteins.) “By displaying the targeting ligands (binding molecules) onto the surface, the T4 capsid gene expression and protein system will be able to efficiently deliver the Cas9 and sgRNA plasmids together into the desired recipient cells. Relevant enzymatically-active proteins Cas9, lambda exonuclease, lambda beta protein and others can be delivered directly at the same time from the T4 nanoparticle.” Seamless gene correction of beta-thalassemia mutations in patient-specific cells Dr. Jinny L. Liu discussed the paper that she, Prof. Lindsay W. Black and their co-authors published in Proceedings of the National Academy of Sciences USA. “Icosahedral viral nanoparticles are essentially 100 nm by 80 nm nanocontainers that allow exogenous genetic material to be packaged in vitro through nucleic acid machinery that generally only allows linear DNA/RNA to be packaged through a portal channel,” Liu tells Phys.org. “However, in vitro protein packaging is generally impossible, because for most viral nanoparticles there is no protein packaging machinery comparable to nucleic acid packaging machinery.” While protein may be chemically cross-linked to the capsid inner surface, this is expected to lead to protein denaturation and loss of enzymatic activity.That being said, nature has evolved solutions to this protein packaging conundrum. During in vivo viral capsid assembly, Liu explains, some bacterial viruses, or bacteriophages, target proteins within the procapsids before the nucleic acid is packaged so as to eject the proteins with the nucleic acid, thereby facilitating infection in conjunction with the nucleic acid. (A procapsid, or prohead, is an immature viral capsid structure formed in the early stages of self-assembly of some bacteriophages. Production and assembly of stable proheads is an essential precursor to bacteriophage genome packaging.) Only a few phages have well-characterized in vivo protein packaging systems, and phage T4 is the best characterized. “Prof. Black’s lab at UMB and my lab at NRL have demonstrated that not only can a specific foreign enzyme – cyclic recombination (Cre) recombinase – be packaged into the capsid in vivo, but also that it is active within the capsid.” This activity was demonstrated by showing the religation (the rejoining of two DNA strands or other molecules by a phosphate ester linkage) of packaged linear DNA flanked with two Cre recombination sites.The paper shows that the substantial space within a T4 nanocontainer accommodates the active Cre enzyme along with exogenous DNA. “For potential applications, T4 can package up to 50 kb exogenous linear DNA containing full-length desired genes along with recombinases, either Cre or λ-red proteins, for specific homologous recombination within the chromosome,” Liu notes. (Homologous recombination is a type of genetic recombination in which nucleotide sequences are exchanged between two similar or identical molecules of DNA.) “We expect that the cas9 enzyme could be encapsidated in a comparable way – and in fact, at least eight different proteins have been encapsidated in this manner. Through homologous recombination, our system can allow the corrected gene to replace the mutated gene in its original location within the chromosome or by precisely knocking out the overactive genes in stem cells.” Liu points out that the T4 delivery vector is safer and better controlled than other viral delivery gene therapy, such as those delivering genes using infectious animal viral vectors to randomly insert the gene within the chromosome. Liu adds that her lab has also been studying cell imaging and drug/gene delivery to eukaryotic cells using T4 tailless nanoparticles, which the researchers demonstrated can enter the eukaryotic cells without causing cell death.A specific example of potential downstream drug and gene therapeutic applications resulting from the new approach is delivery of the toxic protein and linear plasmid that produces neutralizing peptides or antibodies into targeted cancer cells displaying specific cancer markers using high affinity SOC + HOC marker binding proteins on the surface of the capsids, while another example is to use the system for HIV gene therapy. Liu adds that there are several pathways to use this system for gene therapy:Delivering T4 nanoparticles packaged with the recombinase (or ligase) and linear plasmid DNA to produce gp120 or interferon to generate or boost the immune response in patientsDelivering T4 nanoparticles packaged with recombinase (ligase) and the linear soluble CD40 expression plasmid DNA into T lymphocytes or hematopoietic cells to block the infection of HIV-1Inhibiting RNA by delivering the engineered plasmid DNA that can produce decoy RNA for binding the viral sense DNAInhibiting protein by delivering packaged anti-viral antibodies and anti-HIV antibody plasmid DNA In addition to diagnostic and cellular imaging, the T4 nanoparticle gene-protein system can deliver repaired genes to correct human genetic diseases – for example, reversing adenosine deaminase (ADA) deficiency by introducing the protein-DNA complex to express ADA in stem cells. Other broad areas of research impacted by gene therapy technologies, such as genetic defects, cancer, neurological diseases in adults, and aging itself, may also benefit from this study.Moving forward, the scientists want to develop more T4 procapsids packaging exonuclease and other recombinases along with engineered target DNA to demonstrate that the resulting T4 capsids can insert the gene into a stem cell line with a genetic deficiency. “In addition,” Liu concludes, “we’re working on adapting our system to deliver therapeutic peptides or antibodies to cells exposed to or infected by biothreat agents, such as protein toxins or viruses, efficient neutralization of toxin effects. The treatment and cure of cells and tissues exposed to such agents are of a great interest to our biodefense research community.” Journal information: Proceedings of the National Academy of Sciences Explore further The T4 capsid-derived specific exogenous DNA plus protein packaging and eukaryotic cell delivery scheme. (A) DNA encoding a 10-amino acid N-terminal CTS peptide fused to the phage P1 Cre allows synthesis of CTS-Cre and targeting of the enzyme into the early core-scaffold of the T4 procapsid in vivo. Procapsid assembly and maturation-specific viral protease stabilize the procapsid, remove most of the scaffolding core as peptides, and remove the CTS peptide from Cre. Mutations in the viral terminase block DNA packaging and allow a mature but DNA-empty large Cre-containing procapsid to be highly purified from viral-infected bacteria. (B) In vitro packaging into the mature capsid of plasmid DNA containing mCherry driven by a CMV promoter and two loxP sites flanking an SfiI restriction enzyme site that allow the linearization required for packaging. The DNA is packaged into the procapsid by the ATP-driven terminase motor protein (gp17) with high efficiency. (C) The packaged Cre enzyme recircularizes the packaged linear plasmid DNA between the two loxP sites. The DNA-containing capsid is taken up by eukaryotic cells, here without displaying a specific peptide target, or into eukaryotic cells specifically using Soc and Hoc displayed peptides that have high affinity for the RP1 and RP2 receptors, respectively. Credit: Liu JL, et al. (Published online before print August 26, 2014) Viral nanoparticle-encapsidated enzyme and restructured DNA for cell delivery and gene expression. Credit: Liu JL, et al. (2014) Viral nanoparticle-encapsidated enzyme and restructured DNA for cell delivery and gene expression. Proc Natl Acad Sci USA Published online before print August 26, 2014. doi:10.1073/pnas.1321940111 More information: Viral nanoparticle-encapsidated enzyme and restructured DNA for cell delivery and gene expression, Proceedings of the National Academy of Sciences USA, Published online before print August 26, 2014, doi:10.1073/pnas.1321940111 Measurement of the inhibition by endocytosis inhibitors and colocalization with lysosomes in A546-T4–treated A549 cells. (A) Pretreatment with amantadine, specifically stabilizing the clathrin-coated pits, reduced the uptake of A546-T4 NPs by A549 cells in a concentration-dependent manner. (B) Pretreatment with the PI3 kinase inhibitor, wortmannin, also reduced the uptake of A546-T4 in a concentration-dependent manner. (C) An overlapping confocal cell image obtained with a 60× objective with the internalized A546-T4 procapsids (yellow), lysosomes stained with LysoTracker Blue (blue), and the overlapping spots (white). (Scale bar, 10 μm.) (D) A confocal image shows the broad view of treated cells containing overlapping portions (white spots) of lysosomes (blue) with A546-T4 procapsids (yellow). The image was obtained using a 20× objective. (Scale bar, 50 μm.) Credit: Liu JL, et al. (Published online before print August 26, 2014) Viral nanoparticle-encapsidated enzyme and restructured DNA for cell delivery and gene expression. Credit: Liu JL, et al. (2014) Viral nanoparticle-encapsidated enzyme and restructured DNA for cell delivery and gene expression. Proc Natl Acad Sci USA Published online before print August 26, 2014. doi:10.1073/pnas.1321940111 (Phys.org) —By loading any specific protein and nucleic acid into an icosahedral phage T4 capsid-based nanoparticle, the resulting cell delivery vehicle’s ligands can bind to the surface of specific target tissues to deliver the protein/DNA cargo. (Icosahedral viral nanoparticles are evolutionary protein shells assembled in a hierarchical order that results in a stable protein layer and an inner space for accommodating nucleic acids and proteins; a capsid is the protein shell of a virus.) The technique has drug- and gene-delivery applications in human diseases, diagnostic and cellular imaging, and other medical areas. Recently, scientists at US Naval Research Laboratory, Washington, DC and University of Maryland at Baltimore packaged T4 nanoparticles in vivo with active cyclic recombination, or Cre, recombinase (a genetic recombination enzyme used to manipulate genome structure and control gene expression) and in vitro with fluorescent mCherry (a fluorescent protein used as a marker when tagged to molecules and cell components) expression plasmid DNA, and delivered these nanoparticles into cancer cells: When released into cells in the presence of both DNA and protein, the recombinase enhances mCherry expression by circularization (that is, changing the packaged linear DNA into a circular loop). The researchers state that this efficient and specific packaging into capsids and the unpackaging of both DNA and protein with release of the enzymatically altered protein/DNA complexes from the nanoparticles into cells have potential in numerous downstream applications such as genetic and cancer therapeutics. © 2014 Phys.org Citation: Nanocontainers for nanocargo: Delivering genes and proteins for cellular imaging, genetic medicine and cancer therapy (2014, September 16) retrieved 18 August 2019 from https://phys.org/news/2014-09-nanocontainers-nanocargo-genes-proteins-cellular.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

Tagged: , , , , , , , , , , , .

FAA appears to be attempting to expand its authority to moon activities

Posted on by

first_imgThe U.S. Federal Aviation Administration has caused a bit of stir by hinting that it plans to expand its authority to include exploration of the moon and the use of its resources. News agency Reuters has reported that it has obtained a copy of a letter composed by officials with the agency and sent to U.S. based Bigelow Airspace—in it, the agency said it plans to leverage its launching authority by adding licensing authority of moon assets—all to encourage private companies to invest in such activities. The reason such a move has caused a stir, of course, is because it appears that the U.S. agency is attempting to expand its oversight into an area where it does not have the authority to do so. Video: The future of manned moon exploration © 2015 Phys.org Explore further Citation: FAA appears to be attempting to expand its authority to moon activities (2015, February 6) retrieved 18 August 2019 from https://phys.org/news/2015-02-faa-authority-moon.html No one owns the moon or any part of it, which makes it ripe for the taking. A similar scenario is taking place in parts of the northern hemisphere as global warming reveals new unclaimed territory. In years past, land grabs generally resulted in the spoils going to those who came first—and then fought off those that tried to take it away from them. To prevent such a scenario unfolding in a new more civilized world, the United Nations passed an Outer Space treaty back in 1967, which among other things, stipulates that no one country can claim sovereignty over any part of the moon. It also lays out rules for activities on the moon—private entities that go there, for example, must be authorized and supervised by countries belonging to the UN. George Nield, author of the letter, in responding to criticism regarding its intent, claimed that the wording does not imply that the agency is attempting to license moon landings—the agency, he said, was merely trying to reassure Bigelow that it would do its best to protect the company’s assets once they are on the moon. Unfortunately, others do not see it that way. While it is clear that new rules need to be written and agreed to by worldwide consensus, an American agency striking out on its own seems to be a push by the U.S. government to tighten its grip on celestial assets—Reuters claims the letter was coordinated by several agencies, not just the FAA, which included NASA, Commerce and the departments of State and Defense.Regardless of intent, it is likely the letter will cause some in the U.N. or other multi-national organizations to speed up the process of figuring out how to settle land claims and/or disputes on the moon or other celestial bodies, before it becomes necessary to settle things the old-fashioned way. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

Tagged: , , , , , , , , , , , .

Physicists observe magnetic devils staircase

Posted on by

first_img More information: T. Matsuda, et al. “Observation of a Devil’s Staircase in the Novel Spin-Valve System SrCo6O11.” Physical Review Letters. DOI: 10.1103/PhysRevLett.114.236403 Also at arXiv:1412.7945 [cond-mat.str-el] Explore further Citation: Physicists observe magnetic ‘devil’s staircase’ (2015, June 24) retrieved 18 August 2019 from https://phys.org/news/2015-06-physicists-magnetic-devil-staircase.html Devil’s staircase behavior emerges in the magnetic structure of a cobalt oxide material. Three magnetic phases are shown here, where the arrows represent the different spin configurations that define each phase. These phases have nearly degenerate magnetic energies, so they all coexist as stable phases, but can be easily altered by external modifications such as doping. Credit: T. Matsuda, et al. ©2015 American Physical Society Anomalous spin ordering revealed by brilliant synchrotron soft X-rays Now in a new paper published in Physical Review Letters, researchers led by Hiroki Wadati, an associate professor at the University of Tokyo, have observed devil’s staircase behavior in a certain magnetic material: the cobalt oxide SrCo6O11. By analyzing the microscopic behavior of this material, the researchers found that it contains a large number of magnetic structures that have nearly “degenerate,” or equal, magnetic energies. The coexistence of these many nearly degenerate magnetic structures gives rise to the devil’s staircase behavior, which has the appearance of many (in principle, an infinite number of) proportional step-like structures.Although the devil’s staircase behavior emerges from microscopic effects, the behavior is also reflected in the material’s macroscopic properties. One of the most intriguing properties is the material’s giant magnetoresistance, which means that an applied magnetic field changes the material’s electrical resistance. This property could have implications for designing artificial materials with novel functionalities.To uncover these microscale magnetic properties of the cobalt oxide, the researchers used a technique called soft X-ray scattering (RSXS), which involves bombarding a material with X-rays and measuring the energy and momentum of the scattered X-rays. As a relatively recent development, RSXS has proven to be a powerful tool for investigating the ordered structures in solid materials. For one of the first times ever, the researchers here used RSXS with magnetic fields of several Tesla. The technique enabled the researchers to discover several microscale magnetic structures that escaped detection in earlier experiments. The scientists attribute the material’s unusually large number of nearly degenerate magnetic phases—and the resulting devil’s staircase behavior—to competition between the magnetic phases. This competition results in magnetic frustration, as no single phase is strong enough to dominate the others. The results show that strong magnetic frustration is a key ingredient for giving the material its giant magnetoresistance and also makes the material highly sensitive to very low chemical doping. To demonstrate this sensitivity, the researchers showed that substituting just 3% of the strontium atoms with barium atoms destroys almost all of the material’s degenerate magnetic phases, which greatly changes its overall magnetic properties. Because the material’s properties are easily tunable in this way, the scientists hope that this research may offer a path toward engineering and controlling the material’s magnetic and electrical properties for various technological applications. “In future resonant soft X-ray diffraction studies, one can expect to find similar devil’s staircase behavior in other materials,” Wadati told Phys.org. “The devil’s staircase behavior may lead to the development of novel types of spintronics materials, which can use discrete levels of electrical resistivity.”center_img Journal information: Physical Review Letters © 2015 Phys.org (Phys.org)—Many hiking trails feature a “devil’s staircase”—a set of steps that are often steep and difficult to climb. The devil’s staircase is also the name of a mathematical function whose graph exhibits a jagged step-like organization reminiscent of a real staircase, although in a highly ordered fractal pattern. Devil’s staircase behavior emerges in a variety of areas, such as in crystals, phase transitions, and statistical physics. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

Tagged: , , , , , , , , , , , .

Keep surprise on

Posted on by

first_imgWith a focus on landscapes in Italian cinema, Perduto Amor will be screened. The 115 minute film was released in 2003. Directed by Franco Battiato, the film stars Corrado Fortuna, Donatella Finocchiaro, Annamria Gherardi and Tiziana Lodato.It deals with the sojourn of the protagonist Ettore Corvaja, a young Sicilian, between the mid 50s and mid 60s. In the first half of the movie, we are in the 50s in Sicily, and Ettore is a child who lives surrounded by women and seems to be always surprised of what happens around him. He grows between the joie de vivre of the time and the teachings of his mentor, aristocratic culture of the country. In the second part during the economic boom, 20 years later finally he is in Milan. DETAILAt: Istituto Italiano di Cultura, Chanakyapuri When: 22 December Timings: 2 pm onwardslast_img read more

Tagged: , , , , , , , , , , , .

Just express you have nothing to lose

Posted on by

first_imgI’m in college. I’m deeply in love with a junior. She’s in 1st year. I don’t know how to express my feelings to her.Rajeev, HyderabadJust be brave enough to approach her and express. The age old ritual of a romantic love letter might also do the trick. Whatever way you adopt, I suggest, don’t waste time! Just express. Nothing to lose my dear. Woo her, make her feel special, gift her an orchid, take her out to movies, restaurants and just ‘Bol Daalo’!! Best of luck!! Also Read – ‘Playing Jojo was emotionally exhausting’I have recently discovered that my younger brother is homosexual. My parents are not aware. I’m very nervous.Name withheld, DelhiSee my friend, don’t get nervous! It’s fine! I understand, that ‘discovering’ this wasn’t a happy feeling but please don’t create any situation that will lead your brother to take any drastic step or make him feel awkward. If he’s really young, there could be a chance that this ‘phase’ will pass. But, if it doesn’t, please be mature enough to make him feel comfortable as this is his ‘preference’ and being ‘homosexual’ is never an offence or crime! Live and let live… Also Read – Leslie doing new comedy special with NetflixI’m 14 years old. My parents have informed me that they are getting divorced. I have been asked to decide on which parent I choose to stay with.  I’m shattered. I can’t imagine this!Neha, NoidaI’m really sorry to hear that but Neha, they must be getting separated for their reasons. You have to handle yourself with utmost care as you are special. Concentrate on activities that make you feel good – sport, friends, books, movies. Think both from your head and heart and decide on your choice. Living with one doesn’t mean that you will be completely detached from the other. You must spend time with both your parents according to your will. If you think, then you can also opt for a residential school away from your present location. New environment might be best. Convey your decision accordingly. Cheer up girl, life is beautiful and I’m sure, you will be happy always. My husband can’t satisfy me sexually. I’ve got involved with his cousin who lives with us. I’m enjoying sex but feel scared. What should I do?Name withheld, HaryanaGood to hear that you are ‘enjoying’. But yes! This case of cousin living in with you is definitely a reason to worry. I suggest, please be extra careful. Nobody should sense it ever. Temporary joy shouldn’t lead to permanent problems. You have to prioritise your own life and act. Sex is important but not at the cost of your mental peace and long term happiness. Have a love or life query you cannot find an answer to? Send your questions to – roopshashotm@gmail.comlast_img read more

Tagged: , , , , , , , , , , , .