#Solar cooling system keeps water at 9 degrees Celsius for up to three months Maintaining food in places where high temperatures prevail,
using little energy at a low cost, it is now possible with Mexican technology, thanks to the creation of a solar cooling system designed by Susana Elvia Toledo Flores.
The prototype developed in the Research Department in Zeolites, at the Institute of Science of the Meritorious University of Puebla (BUAP), in center Mexico,
works 24 hours and keeps the cold for up to three months. The researcher developed the prototype in the Black Mountain range of the state
where she has achieve to maintain water at nine degrees Celsius"with that temperature we can cool food,
though the goal is to get as low as five, with this fish can be preserved without denaturing its proteins."
"The BUAP design is inexpensive, easy to manufacture and environmentally beneficial.""Normal cooling systems use chlorofluorocarbon chemicals that destroy the ozone layer
and contribute to greenhouse gases, ours is friendly to the environment, "explains Toledo Flores. It works with solar radiation and the cooling is achieved by means of a thermodynamic adsorption-desorption cycle lasting 24 hours.
Methanol is used as a refrigerant and as zeolite (mineral) as an adsorbent. Toledo Flores says the system has two stages, during the day"warming,
desorption and the period of condensation happens. Solar energy heats the zeolite and increases the methanol vapor pressure,
the refrigerant is condensed and stored in a tank flowing to the evaporator.""Overnight the cooling process is achieved,
adsorption and evaporation period is performed.""The adsorbent bed temperature decreases after sunset, therefore, the refrigerant pressure is reduced
and evaporates while the absorbent is cooled. During this period the coolant begins to evaporate and is adsorbed again by zeolite generating cooling temperatures of five degrees Celsius.
The adsorption process continues all night until morning.""The equipment is composed of a solar collector, adsorbent bed, condenser and evaporator.
To build it, the researcher calculates the amount of water to be cooled, thereby knows how many zeolite to use.
She also considers the room temperature, in this case of 20 degrees Celsius. Furthermore, the system"is designed
not only to cool foods. It may also serve as an air conditioning, for example, in communities like Tecali de Herrera, Puebla,
where there are areas without electricity and the system could adapt well to preserve their foods
and medicine, bringing them better quality of life,""says Toledo Flores. The project was presented at the International Congress of Solar energy at Germany y
#Future antibiotic-making kit for amateurs? Kit could one day Be led by widely available Professor Jeffrey Bode of the Institute of Transformative Biomolecules at Nagoya University in Japan,
the research team is now applying its"synthetic fermentation"strategy to make molecular kits that can be used simply
and safely to discover novel antibiotics. Microorganisms can synthesise mixtures of complex organic molecules, such as antibiotics, from simple organic building blocks by fermentation.
Inspired by this approach, Professor Bode and his colleagues found that they could make large mixtures of biologically active compounds from a few chemical ingredients in just a few hours,
rather than the months it would normally take trained chemists. To do so, the team applied a powerful bond-making reaction, called KAHA (alphaketoacid-hydroxylamine) ligation,
which enables the rapid formation of"amide"chemical bonds, found in peptides and proteins. The KAHA ligation uses special types of organic molecules to form new bonds without the usual need for toxic chemical reagents.
Using synthetic fermentation, the researchers have shown that about 6, 000 novel peptides can be made from only 23 building blocks.
What's more, they have demonstrated the practicality of this approach by identifying a novel molecule that blocks a key enzyme used by the hepatitis C virus."Our dream is to provide a do-it-yourself method--one that can be applied by anyone,
anywhere to make and assess millions of organic molecules, without using dangerous reagents, "says Professor Bode."
"For example, we envision that synthetic fermentation could be used by farmers to generate and identify new antibacterial or antifungal molecules to treat plant diseases."
"By combining a handful of molecules in a variety of ways, a farmer could identify a novel combination that treats plant infections.
He adds that the next step is to determine the most efficient way to screen the thousands
or even millions of chemical compounds that can be generated using synthetic fermentation n
#A new breakthrough in thermoelectric materials French physicist Jean Charles Athanase Peltier discovered a key concept necessary for thermoelectric (TE) temperature control in 1834.
His findings were so significant, TE devices are referred now commonly to Peltier devices. Since his work, there have been steady advancements in materials and design.
Despite the technological sophistication Peltier devices, they are still less energy efficient than traditional compressor/evaporation cooling.
In the 1960's, Peltier devices were made primarily from Bismuth-Telluride (Bi2te3) or Antimony-Telluride (Sb2te3) alloys and had a peak efficiency (zt) of 1. 1,
meaning the electricity going in was only slightly less than the heat coming out. Since the 1960's there have been incremental advancements in alloy technology used in Peltier devices.
In 2014, researchers in South korea at IBS Center for Integrated Nanostructure Physics along with Samsung Advanced Institute of technology, the Department of Nano Applied Engineering at Kangwon National University, the Department of energy Science
at Sungkyunkwan University, and Materials science department at California Institute of technology California, USA have formulated a new method for creating a novel and much more efficient TE alloy.
TE alloys are special because the metals have an incredibly high melting point. Instead of melting the metals to fuse them,
they are combined through a process called sintering which uses heat and/or pressure to join the small,
metallic granules. The joint team, including IBS researchers, used a process called liquid-flow assisted sintering
which combined all three antimony, bismuth and telluride granules into one alloy (Bi0. 5sb1. 5te3).
Additional melted tellurium was used as the liquid between the Bi0. 5sb1. 5te3 granules to help fuse them into a solid alloy,
and excess Te is expelled in the process. By creating the alloy this way, the joints between the fused grains,
also known as the grain boundaries, took on a special property. Traditionally sintered Bi0. 5sb1. 5te3 have thick, coarse joints
which have led to a decrease in both thermal and electrical conductivity. The new liquid-phase sintering creates grain boundaries
which are organized and aligned in seams called dislocation arrays. These dislocation arrays greatly reduce their thermal conduction
leading to an enhancement of their thermoelectric conversion efficiency. In tests, the efficiency (zt) reached 2. 01 at 320 K within the range of 1. 86 0. 15 at 320 K (46.85 C) for 30 samples,
nearly doubling the industry standard. When the melt spun Bi0. 5sb1. 5te3 alloy is used in a Peltier cooler,
as electrical vehicles and personal electronic devices become more ubiquitous in our daily lives, it is becoming increasingly necessary to have more efficient systems for localized electrical power generation and effective cooling mechanisms.
This new thermoelectric alloy paves the way for the future of modern TE devices s
#Possible progress against Parkinson's and good news for stem cell therapies Parkinson's, which affect as many 10 million people in the world,
is caused by a depletion of dopamine-producing neurons in the brain. Current treatments include medications and electrical implants in the brain
which causes severe adverse effects over time and fail to prevent disease progression. Several studies have indicated that the transplantation of embryonic stem cells improves motor functions in animal models.
However, until now, the procedure has shown to be unsafe, because of the risk of tumors upon transplantation.
To address this issue the researchers tested for the first time to pre-treat undifferentiated mouse embryonic stem cells with mitomycin C a drug already prescribed to treat cancer.
The substance blocks the DNA replication and prevents the cells to multiply out of control.
The first one, the control group, did not receive the stem cell implant. The second one, received the implant of stem cells
which were treated not with mitomycin C and the third one received the mitomycin C treated cells.
After the injection of 50 000 untreated stem cells, the animals of the second group showed improvement in motor functions
These animals also developed intracerebral tumors. In contrast, animals receiving the treated stem cells showed improvement of Parkinson's symptoms
and survived until the end of the observation period of 12 weeks post-transplant with no tumors detected.
Four of these mice were monitored for as long as 15 months with no signs of pathology. Furthermore, the scientists have shown also that treating the stem cells with mitomycin C induced a fourfold increase in the release of dopamine after in vitro differentiation."
"This simple strategy of shortly exposing pluripotent stem cells to an anticancer drug turned the transplant safer,
by eliminating the risk of tumor formation, "says the leader of the study Stevens Rehen, Professor at UFRJ and researcher at IDOR.
The discovery, reported on April in the journal Frontiers in Cellular neuroscience, could pave the way for researchers
and physicians to propose a clinical trial using pluripotent stem cells treated with mitomycin C prior to transplant to treat Parkinson's patients and also other neurodegenerative conditions."
"Our technique with mitomycin C may speed the proposal of clinical trials with pluripotent cells to several human diseases,
#One dollar blood test using gold nanoparticles outperforms PSA screen for prostate cancer, study suggests The simple test developed by University of Central Florida scientist Qun"Treen"Huo holds the promise of earlier detection of one of the deadliest cancers among men.
It would also reduce the number of unnecessary and invasive biopsies stemming from the less precise PSA test that's now used."
"It's fantastic, "said Dr. Inoel Rivera, a urologic oncologist at Florida Hospital Cancer Institute,
which collaborated with Huo on the recent pilot studies.""It's a simple test. It's much better than the test we have right now,
"When a cancerous tumor begins to develop, the body mobilizes to produce antibodies. Huo's test detects that immune response using gold nanoparticles about 10,000 times smaller than a freckle.
When a few drops of blood serum from a finger prick are mixed with the gold nanoparticles, certain cancer biomarkers cling to the surface of the tiny particles,
increasing their size and causing them to clump together. Among researchers, gold nanoparticles are known for their extraordinary efficiency at absorbing
and scattering light. Huo and her team at UCF's Nanoscience Technology Center developed a technique known as nanoparticle-enabled dynamic light scattering assay (Nanodlsay) to measure the size of the particles by analyzing the light they throw off.
That size reveals whether a patient has prostate cancer and how advanced it may be. And although it uses gold,
the test is cheap. A small bottle of nanoparticles suspended in water costs about $250,
and contains enough for about 2, 500 tests.""What's different and unique about our technique is it's a very simple process,
and the material required for the test is less than $1, "Huo said.""And because it's low-cost,
we're hoping most people can have this test in their doctor's office. If we can catch this cancer in its early stages,
the impact is going to be big.""After lung cancer, prostate cancer is the second-leading killer cancer among men, with more than 240,000 new diagnoses and 28,000 deaths every year.
The most commonly used screening tool is the PSA, but it produces so many false-positive results--leading to painful biopsies
and extreme treatments--that one of its discoverers recently called it"hardly more effective than a coin toss."
"Pilot studies found Huo's technique is significantly more exact. The test determines with 90 to 95 percent confidence that the result is not false-positive.
D c. Huo's team is pursuing more extensive clinical validation studies with Florida Hospital and others,
including the VA Medical center Orlando. She hopes to complete major clinical trials and see the test being used by physicians in two to three years.
Huo also is researching her technique's effectiveness as a screening tool for other tumors."
"Potentially, we could have a universal screening test for cancer, "she said.""Our vision is to develop an array of blood tests for early detection and diagnosis of all major cancer types,
and these blood tests are all based on the same technique and same procedure.""Huo co-founded Nano Discovery Inc.,a startup company headquartered in a UCF Business Incubator,
The company manufacturers a test device specifically for medical research and diagnostic purposes s
#Engineers gain control of gene activity by synthetically creating key component of epigenome The new technology allows researchers to turn on specific gene promoters
and enhancers--pieces of the genome that control gene activity--by chemically manipulating proteins that package DNA.
This web of biomolecules that supports and controls gene activity is known as the epigenome. The researchers say having the ability to steer the epigenome will help them explore the roles that particular promoters
or the risk for genetic disease and it could provide a new avenue for gene therapies and guiding stem cell differentiation.
The study appears online April 6 in Nature Biotechnology.""The epigenome is associated everything with the genome other than the actual genetic sequence,
and is just as important as our DNA in determining cell function in healthy and diseased conditions,
"said Charles Gersbach, assistant professor of biomedical engineering at Duke.""That becomes immediately obvious when you consider that we have over 200 cell types,
"But there's also many other pieces of the genome called enhancers that aren't next to any genes at all,
"Timothy Reddy, assistant professor of biostatistics and bioinformatics at Duke, has spent the better part of a decade mapping millions of these enhancers across the human genome.
An enhancer might affect a gene next door or several genes across the genome--or maybe none at all.
"There are already drugs that will affect enhancers across the whole genome, but that's like scorching the earth,"said Reddy."
and modify very specific epigenetic marks in very specific places to find out what individual enhancers are doing."
"Reddy found that specificity by teaming up with Gersbach, his neighbor within Duke's Center for Genomic and Computational biology,
and paste DNA sequences in the human genome. For this epigenome editing application, Gersbach silenced the DNA-cutting mechanism of CRISPR
so that we can alter the DNA's packaging at that specific site, "said Reddy. Gersbach and Reddy put their artificial epigenetic agent to the test by targeting a few well-studied gene promoters and enhancers.
While these histone modifications have long been associated with gene activity, it wasn't clear if they were enough to turn genes on.
--or even families of genes--by targeting enhancers at distant locations in the genome--something that their previous gene activators could not do.
"Some genetic diseases are straightforward --if you have a mutation within a particular gene, then you have said the disease
Isaac Hilton, postdoctoral fellow in the Gersbach Lab and first author of the study.""But many diseases, like cancer, cardiovascular disease or neurodegenerative conditions, have a much more complex genetic component.
Many different variations in the genome sequence can affect your risk of disease, and this genetic variation can occur in these enhancers that Tim has identified,
where they can change the levels of gene expression. With this technology, we can explore what exactly it is that they're doing
and how it relates to disease or response to drug therapies.""Gersbach added, "Not only can you start to answer those questions,
but you might be able to use this technique for gene therapy to activate genes that have been silenced abnormally
or to control the paths that stem cells take toward becoming different types of cells.
These are all directions we will be pursuing in the future.""This work was supported by the National institutes of health (R01da036865, U01hg007900, DP2OD008586, P30ar066527) and the National Science Foundation (CBET-1151035
#Researchers discover N-type polymer for fast organic battery The discovery relies upon a"conjugated redox polymer"design with a naphthalene-bithiophene polymer,
which has traditionally been used for applications including transistors and solar cells. With the use of lithium ions as dopant, researchers found it offered significant electronic conductivity
and remained stable and reversible through thousands of cycles of charging and discharging energy. The breakthrough, described in the Journal of the American Chemical Society and featured as ACS Editors'Choice for open access, addresses a decades-long challenge for electron-transport conducting polymers,
said Yan Yao, assistant professor of electrical and computer engineering at the UH Cullen College of Engineering and lead author of the paper.
Researchers have recognized long the promise of functional organic polymers, but until now have not been successful in developing an efficient electron-transport conducting polymer to pair with the established hole-transporting polymers.
The lithium-doped naphthalene-bithiophene polymer proved both to exhibit significant electronic conductivity and to be stable through 3,
000 cycles of charging and discharging energy, Yao said. The discovery could lead to a cheaper alternative to traditional inorganic-based energy devices,
including lithium batteries. Ultimately Yao said, it could translate into less expensive consumer devices and even less expensive electric cars.
Yao's research group focuses on green and sustainable organic materials for energy generation and storage.
He is also a principal investigator for the Texas Center for Superconductivity at UH. Yanliang Liang, a research associate at UH and first author on the paper, said researchers aren't trying to compete directly with conventional lithium-ion batteries."
"We are trying to demonstrate a new direction, "he said. Liang said conventional inorganic metal-based batteries
and energy storage devices are expensive partly because the materials used to make them, including cobalt and silicon-based compounds,
require huge energy expenditures to process. Organic polymers can be processed at relatively low temperatures, lowering the cost.
They also produce less CO2, he said, adding to their environmental advantage. And while conventional materials are finite,
organic polymers could potentially be synthesized from biomass.""Organic-conjugated polymers are emerging as a materials class for energy-related applications,
enabling a path to a more sustainable energy landscape without the need of energy-intensive, expensive and sometimes toxic metal-based compounds,
"the researchers wrote, concluding that"a model polymer, P (NDI2OD-T2), was stably and reversibly n-doped to a high doping level of 2. 0,
a significant progress for electron-transporting? -conjugated polymers...With rational molecular design? -conjugated redox polymers will establish new design space in polymer chemistry
and see widespread applications, especially in energy-related ones such as batteries, supercapacitors and thermoelectrics.""The basic polymer used in the work was discovered in 2009;
Yao said it was provided by members of the research team from Polyera Corporation, a technology company based in Illinois
. Although naphthalene-bithiophene has been used for transistors and other applications since its discovery, this is the first time it has been converted for use in energy storage.
That was done through the addition of lithium and raised the polymer's doping level from a previously reported 0. 1 to 2. 0. The results are record-setting.
The polymer exhibits the fastest charge-discharge performance for an organic material under practical measurement conditions,
allowing a battery to be charged 80 percent within 6 seconds and fully charged in another 18 seconds,
Liang said. Conventional inorganic batteries still are capable of holding more energy than the organic battery,
and Yao said work will continue to improve the storage capacity of the material. His group also will continue to do basic scientific research on the polymer to learn more about it,
he said d
#Discovery may be breakthrough for hydrogen cars The team's new findings, published Monday in the Proceedings of the National Academy of Sciences, could help speed the widespread arrival of the hydrogen-powered vehicles in a way that is inexpensive
and has extremely low carbon emissions.""This means we have demonstrated the most important step toward a hydrogen economy--producing distributed and affordable green hydrogen from local biomass resources,
"said Percival Zhang, a professor in the Department of Biological Systems Engineering, which is in both the College of Agriculture and Life sciences and the College of Engineering.
The team already has received significant funding for the next step of the project, which is to scale up production to a demonstration size."
"Although it is difficult to predict cost at this point, this work represents a revolutionary approach that offers many new advantages,
"said Lonnie O. Ingram, director of the Florida Center for Renewable Chemicals and Fuels at the University of Florida,
who is familiar with the work but not associated with the team.""These researchers have broadened certainly the scope of our thinking about metabolism
and how it plays into the future of alternative energy production.""Joe Rollin, a former doctoral student of Zhang's at Virginia Tech and cofounder with Zhang of the start-up company Cell-free Bioinnovations, is the lead author on the paper.
This work builds upon previous studies Zhang's team has done with xylose, the most abundant simple plant pentose sugar,
to produce hydrogen yields that previously were attainable only in theory. Their new discovery is unique in two ways.
Unlike other hydrogen fuel production methods that rely on highly processed sugars, the Virginia Tech team used dirty biomass--the husks and stalks of corn plants--to create their fuel.
This not only reduces the initial expense of creating the fuel it enables the use of a fuel source readily available near the processing plants,
making the creation of the fuel a local enterprise. Rollin used a genetic algorithm along with a series of complex mathematical expressions to analyze each step of the enzymatic process that breaks down corn stover into hydrogen and carbon dioxide.
He also confirmed the ability of this system to use both sugars glucose and xylose at the same time,
which increases the rate at which the hydrogen is released. Typically in biological conversions, these two sugars can only be used sequentially, not simultaneously
which adds time and money to the process. One of the biggest hurdles to widespread hydrogen use is the capital cost required to produce the fuel from natural gas in large facilities.
Distribution of the hydrogen to users of fuel cell vehicles is another key challenge. Rollin's model increased reaction rates by threefold, decreasing the required facility size to about the size of a gas station,
which reduces associated capital costs. The dominant current method for producing hydrogen uses natural gas, which is expensive to distribute
and causes fossil carbon emissions. To produce distributed hydrogen at affordable costs product yield, reaction rate,
and product separation must be addressed. In terms of product yield, the use of cell-free artificial enzymatic pathway not only breaks the natural limit of hydrogen-producing microorganisms by three times
but also avoids complicated sugar flux regulation. The team also increased enzymatic generation rates. This reaction rate is fast enough for hydrogen production in distributed hydrogen-fueling stations.
The achieved reaction rate is at least 10 times that of the fastest photo-hydrogen production system.
The reaction the researchers studied takes place at modest conditions. This means that hydrogen can be separated easily from aqueous reactants and enzymes.
Also enzymatic reactions such as those being used in this system generate high-purity hydrogen, perfect for hydrogen fuel cell vehicles.
The modest reaction conditions also indicate the feasibility of low-capital requirements for building distributed hydrogen generating
and fueling stations based on this technology.""We believe this exciting technology has the potential to enable the widespread use of hydrogen fuel cell vehicles around the world
and displace fossil fuels, "Rollin said d
#First metal-free catalyst created for rechargeable zinc-air batteries Zinc-air batteries are expected to be safer, lighter, cheaper and more powerful and durable than lithium-ion batteries common in mobile phones and laptops and increasingly used in hybrid and electric cars.
This carbon-based catalyst works efficiently in both the oxygen reduction reaction and oxygen evolution reaction, making the battery rechargeable.
The catalyst is also inexpensive, easy to make and more ecological than most of the alternative materials.
The research is in the online edition of Nature Nanotechnology.""With batteries, cost is always an issue
and metal-free catalysts can reduce cost while improving performance,"said Liming Dai, professor of macromolecular science and engineering at Case Western Reserve University and senior author of the study."
"These batteries could be used in computers, data stations, for lighting--anyplace batteries are used now.""Dai worked with Case Western Reserve postdoctor Jintao Zhang,
who performed experimental work; and North Texas University's Zhenhai Xia, professor of materials science and engineering, and Zhenghang Zhao, a Phd student, who performed theoretical simulations.
Zinc-air batteries mix oxygen from the air with zinc in a liquid alkaline electrolyte to create a charge.
The batteries can have three times the energy density of lithium-ion batteries, but have been sluggish. To counter that problem,
researchers are seeking different catalyst materials. This catalyst is a stable carbon aerogel, or foam, with pores ranging from 2 to 50 nanometers in diameter, providing enormous surface area and room for the battery electrolyte to diffuse.
The researchers followed a foam-making procedure published by Stanford university scientists in 2012. They polymerized molecules of the organic compound aniline into long chains in a phytic acid solution, then freeze-dried the three-dimensional hydrogel into an aerogel."
"What we did that's new is carbonized the 3-D structure, changing it into a graphitic carbon material,
"Zhang said. To do that, the researchers heated the aerogel to 1, 000 degrees Celsius in the absence of oxygen.
The process, called pyrolysis, caused a thermochemical reaction, turning the foam into a graphitic network,
with many graphene edges that proved to be crucial to catalysis."This is a low-cost, one-step, scalable process,
"Dai said.""The electrocatalyst produces comparable or better results than more costly materials.""The aniline infuses,
or dopes, the foam with nitrogen, which enhances the oxygen reduction reaction. Phytic acid infuses the foam with phosphorus."The co-doping of nitrogen
and phosphorus enhances both the oxygen reduction and oxygen evolution reactions, as confirmed by the first-principles calculations,
"Xia said. In comparisons, the carbon foam's performance in a primary, or non-rechargeable battery and a rechargeable battery matched
or surpassed that of expensive platinum/metal oxide-based catalysts. And, it had better long-term stability.
The carbon foam also matched or outperformed most previously reported metal-free catalysts, even recently developed carbon-based catalysts with metals.
Moving forward, Dai's team has begun to further optimize the process while also investigating other graphitic carbon materials co-doped with different elements for possible use in other energy and environmental technologies.
Dai's lab previously developed carbon-based catalysts that perform comparably or better than more expensive metal-based catalysts used in alkaline and acidic fuel cells and in dye-sensitized solar cells."
"Maybe it's time to push for metal-free catalysts in commercial devices, "Dai said d
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