When damaged many plants release hydrocarbons called volatile organic compounds similar to the compounds that cause the characteristic smell of freshly cut grass.
when this odor is mimicked in the laboratory with a mix of synthetic compounds said Prof.
prevent certain diseasesscientists using sophisticated imaging techniques have observed a molecular protein folding process that may help medical researchers understand
So there are special protein machines known as molecular chaperones in the cell that help proteins fold.
In the cell enzymes for example are specialized proteins that help speed biological processes along by binding molecules and bringing them together in just the right way.
And the proteins--those little beads on the string that are designed to fold up like origami--are folded to position all these beads in three-dimensional space to perfectly wrap around those molecules
and parts of the molecule moved to peel the chaperone box away from the bound protein--or gift in the box.
prevent certain diseasesscientists using sophisticated imaging techniques have observed a molecular protein folding process that may help medical researchers understand
So there are special protein machines known as molecular chaperones in the cell that help proteins fold.
In the cell enzymes for example are specialized proteins that help speed biological processes along by binding molecules and bringing them together in just the right way.
And the proteins--those little beads on the string that are designed to fold up like origami--are folded to position all these beads in three-dimensional space to perfectly wrap around those molecules
and parts of the molecule moved to peel the chaperone box away from the bound protein--or gift in the box.
If trees do fail to regenerate it could further reduce ecosystem carbon storage and amplify the greenhouse effect the study said.
This will help researchers to better understand the molecular mechanisms behind infection and develop new approaches for controlling this devastating pathogen.
and multiple compounds are used to target any and all threats to the crop including compounds illegal in the U s. she says.
While some fishers have died from either directly consuming flavored rodenticides or by consuming prey that had ingested recently the poisons exposure may also predispose animals to dying from other causes.
and multiple compounds are used to target any and all threats to the crop including compounds illegal in the U s. she says.
While some fishers have died from either directly consuming flavored rodenticides or by consuming prey that had ingested recently the poisons exposure may also predispose animals to dying from other causes.
and find out whether vegetables cycle those compounds based on circadian rhythms. Arabidopsis and cabbage are related so Braam's team began their research by attempting to entrain the clocks of cabbage in the same way they had Arabidopsis.
One of these an antioxidant called glucoraphanin or 4-MSO is known a anticancer compound that has been studied previously in broccoli and other vegetables.
Understanding this molecular back-and-forth at all the different levels and stages will be useful to either engineer the process
#Farming carbon: Study reveals potent carbon-storage potential of human-made wetlandsafter being drained by the millions of acres to make way for agriculture wetlands are staging a small comeback these days on farms.
Some farmers restore or construct wetlands alongside their fields to trap nitrogen and phosphorus runoff and research shows these systems can also retain pesticides antibiotics and other agricultural pollutants.
and co-author Blanca Bernal report that two 15-year-old constructed marshes in Ohio accumulated soil carbon at an average annual rate of 2150 pounds per acre--or just over one ton of carbon per acre
and 26%faster than the two were adding soil carbon five years ago. And by year 15 each wetland had a soil carbon pool of more than 30000 pounds per acre an amount equaling
or exceeding the carbon stored by forests and farmlands. What this suggests Mitsch says is that researchers
and land managers shouldn't ignore restored and human-made wetlands as they look for places to store
or sequester carbon long-term. For more than a decade for example scientists have been studying the potential of no-tillage planting of pastures and other farm practices to store carbon in agricultural lands
which cover roughly one-third of Earth's land area. Yet when created wetlands are discussed in agricultural circles it's almost always in the context of water quality.
let's add carbon to the list Mitsch says. If you happen to build a wetland to remove nitrogen for example then once you have it it's probably accumulating carbon too.
In fact wetlands in agricultural landscapes may sequester carbon very quickly because high-nutrient conditions promote the growth of cattail reeds
and other wetland big boys that produce a lot of plant biomass and carbon Mitsch says. Once carbon ends up in wetland soil it can also remain there for hundreds to thousands of years because of waterlogged conditions that inhibit microbial decomposition.
And carbon is a big deal--any carbon sinks that we find we should be protecting Mitsch says.
Then we're going even further by saying: We've lost half of our wetlands in the United states
so let's not only protect the wetlands we have remaining but also build some more. At the same time he acknowledges that wetlands emit the powerful greenhouse gas (GHG) methane leading some to argue that wetlands shouldn't be created as a means to sequester carbon
and mitigate climate change. But in a new analysis that modeled carbon fluxes over 100 years from the two constructed Ohio marshes
and 19 other wetlands worldwide Mitsch Bernal and others demonstrated that most wetlands are net carbon sinks even
when methane emissions are factored in. And among the best sinks were the wetlands in Ohio possibly due to flow-through conditions that promoted rapid carbon storage
while minimizing methane losses the authors hypothesize. The concerns about methane emissions and even his own promising findings point to something else Mitsch cautions:
And now we're seeing that they're very important for retaining carbon. So they're multidimensional systems
which concludes that more than half of expectant mothers routinely use these chemical compounds. Spanish researchers have described the use of domestic pesticides during pregnancy and the first year of life in nearly 2500 women and children in Sabadell Guipã zcoa and various areas of Asturias and the Valencian Community.
Conceivable aggravation of forest decline by climate changea new type of electron microscope enabled the observation of particle deliquescence and dynamics under changing air humidity.
Particularly because air concentrations of hygroscopic particles have increased largely within the last decades says Dr. Burkhardt.
study showsa new study shows that the predator-prey relationship can affect the flow of carbon through an ecosystem.
This previously unmeasured influence on the environment may offer a new way of looking at biodiversity management and carbon storage for climate change.
and spiders--herbivores and predators in the study's food chain--and how it affects the movement of carbon through a grassland ecosystem.
Carbon the basic building block of all organic tissue moves through the food chain at varying speeds depending on
The researchers manipulated the food chains of grassland ecosystem to see how the levels of carbon would change over time.
which allowed the team to track the carbon levels by periodically taking leaf root and dead animal samples.
The study found that the presence of spiders drove up the rate of carbon uptake by the plants by about 1. 4 times more than
It was revealed also that the pattern of carbon storage in the plants changed when both herbivores and carnivores were present.
At the same time the grasses stored more carbon in their roots in a response to being disturbed at low levels
In cases where only herbivores were present the plants stored less carbon overall likely due to the more intense eating habits of the herbivores that put pressure on plants to reduce their storage
and breathe out carbon more. These stress impacts then caused both the plants and the herbivores to change their behaviors and change the composition of their local environment.
-and-prey dynamics that drive the carbon cycle and so protecting lands and storing carbon could be linked at the same time.
It's going to force some thinking about the vital roles of animals in regulating carbon concludes Dr. Schmitz pointing to the fact that the UN's body of scientific experts who study climate change don't consider these multiplier effects in their models.
These biomarkers were CD68 a marker for inflammatory cells and adiponectin a molecule with a known role in the development of metabolic syndrome.
which comes in the form of long cellulose molecules packed inside the leaf clippings the ants deliver.
#Unzipped nanotubes unlock potential for batteriesresearchers at Rice university have come up with a new way to boost the efficiency of the ubiquitous lithium ion (LI) battery by employing ribbons of graphene that start as carbon nanotubes.
Proof-of-concept anodes--the part of the battery that stores lithium ions--built with graphene nanoribbons (GNRS)
In the new experiments the Rice lab mixed graphene nanoribbons and tin oxide particles about 10 nanometers wide in a slurry with a cellulose gum binder and a bit of water spread it on a current collector
GNRS are a single atom thick and thousands of times longer than they are wide.
but also help deliver lithium ions to the nanoparticles. Lab tests showed initial charge capacities of more than 1520 milliamp hours per gram (mah/g). Over repeated charge-discharge cycles the material settled into a solid 825 mah/g. It took about two months to go through 50
Lithium ions tend to expand the material they inhabit and the material contracts when they're pulled away.
and lose their ability to store ions. Other labs at Rice have made breakthroughs that help solve the expansion problem by breaking treated silicon into a powder achieving great capacity and many cycles.
Since the tin oxide particles are only a few nanometers in size and permitted to remain that way by being dispersed on GNR surfaces the volume changes in the nanoparticles are not dramatic.
what we're doing here in the Arctic into perspective said Miller principal investigator of the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) a five-year NASA-led field campaign studying how climate change is affecting the Arctic's carbon cycle.
and animals from decomposing so each year another layer gets added to the reservoirs of organic carbon sequestered just beneath the topsoil.
Over hundreds of millennia Arctic permafrost soils have accumulated vast stores of organic carbon--an estimated 1400 to 1850 petagrams of it (a petagram is 2. 2 trillion pounds or 1 billion metric tons.
That's about half of all the estimated organic carbon stored in Earth's soils. In comparison about 350 petagrams of carbon have been emitted from all fossil-fuel combustion and human activities since 1850.
Most of this carbon is located in thaw-vulnerable topsoils within 10 feet (3 meters) of the surface.
But as scientists are learning permafrost --and its stored carbon--may not be as permanent as its name implies.
And that has concerned them. Permafrost soils are warming even faster than Arctic air temperatures--as much as 2. 7 to 4. 5 degrees Fahrenheit (1. 5 to 2. 5 degrees Celsius) in just the past 30 years
As heat from Earth's surface penetrates into permafrost it threatens to mobilize these organic carbon reservoirs
and release them into the atmosphere as carbon dioxide and methane upsetting the Arctic's carbon balance and greatly exacerbating global warming.
Scientists want to know how much permafrost carbon may be vulnerable to release as Earth's climate warms
and thawing permafrost are having on Arctic carbon emissions. CARVE is testing hypotheses that Arctic carbon reservoirs are vulnerable to climate warming
while delivering the first direct measurements and detailed regional maps of Arctic carbon dioxide and methane sources and demonstrating new remote sensing and modeling capabilities.
and accurate climate models to know with confidence how the balance of carbon among living things will respond to climate change
CARVE shows you need to fly very close to the surface in the Arctic to capture the interesting exchanges of carbon taking place between Earth's surface
This instrument is an airborne simulator for NASA's Orbiting Carbon Observatory-2 (OCO-2) mission to be launched in 2014.
and Alpine Research Stable Isotope Laboratory and Radiocarbon Laboratory in Boulder for analyses to determine the carbon's sources
Historically the cold wet soils of Arctic ecosystems have stored more carbon than they have released. If climate change causes the Arctic to get warmer and drier scientists expect most of the carbon to be released as carbon dioxide.
If it gets warmer and wetter most will be in the form of methane. The distinction is critical.
Molecule per molecule methane is 22 times more potent as a greenhouse gas than carbon dioxide on a 100-year timescale and 105 times more potent on a 20-year timescale.
If just one percent of the permafrost carbon released over a short time period is methane it will have the same greenhouse impact as the 99 percent that is released as carbon dioxide.
and whether high northern latitude regions generate or store carbon. CARVE is also studying wildfire impacts on the Arctic's carbon cycle.
Fires in boreal forests or tundra accelerate the thawing of permafrost and carbon release. Detailed fire observation records since 1942 show the average annual number of Alaska wildfires has increased
CARVE's simultaneous measurements of greenhouse gases will help quantify how much carbon is released to the atmosphere from fires in Alaska--a crucial and uncertain element of its carbon budget.
or make plants more resistant to disease says the senior investigator Joseph R. Ecker head of Salk's Plant Molecular and Cellular Biology laboratory.
I have been trying for several decades to understand how a simple gas--two carbons and four hydrogens--can cause such profound changes in a plant Ecker says.
Logging may have greater impact on carbon emissions than previously thoughtusing wood for energy is considered cleaner than fossil fuels
but a Dartmouth College-led study finds that logging may release large amounts of carbon stored in deep forest soils.
Global atmospheric studies often don't consider carbon in deep (or mineral) soil because it is thought to be stable
But the Dartmouth findings show deep soil can play an important role in carbon emissions in clear-cutting and other intensive forest management practices.
and that forest carbon analyses are incomplete unless they include deep soil which stores more than 50 percent of the carbon in forest soils.
Our paper suggests the carbon in the mineral soil may change more rapidly and result in increases in atmospheric carbon dioxide as a result of disturbances such as logging said Dartmouth Professor Andrew Friedland a co-author.
Our paper suggests that increased reliance on wood may have unintended the effect of increasing the transfer of carbon from the mineral soil to the atmosphere.
So the intended goal of reducing carbon in the atmosphere may not be met. The federal government is looking to wood wind solar hydropower
and other renewable energy sources to address concerns about climate change and energy security. Woody biomass which includes trees grown on plantations managed natural forests
Mineral soil carbon responses can vary highly depending on harvesting intensity surface disturbance and soil type.
and understanding forest carbon cycles requires an in depth analysis of the storage in and fluxes among different forest carbon pools
and biomass harvesting on elemental cycling processes in high-elevation forests in the Northeastern United states. He considers many elements including carbon trace elements such as lead and major elements such as nitrogen and calcium.
and phosphorus (P) attached to soil particles. But no-till requires herbicides to control weeds
The blood samples were tested for levels of 11 pesticides and 36 polychlorinated biphenyl (PCB) compounds. According to the findings all participants had detectable concentrations of at least one-quarter of the analyzed chemicals
Fetal heart rate effects were observed not consistently across all of the compounds analyzed; when effects were seen higher chemical exposures were associated with reductions in fetal heart rate accelerations an indicator of fetal wellbeing.
higher concentrations of 7 of 10 organochlorine compounds were associated positively with one of more measures of more frequent and more vigorous fetal motor activity.
Semiconducting films for atom-thick circuitsscientists at Rice university and Oak ridge National Laboratory (ORNL) have advanced on the goal of two-dimensional electronics with a method to control the growth of uniform atomic layers of molybdenum disulfide (MDS.
Graphene and hbn are flat with arrays of hexagons formed by their constituent atoms. But while MDS looks hexagonal
when viewed from above it is actually a stack with a layer of molybdenum atoms between two layers of sulfur atoms.
and carbon atoms would bind. We're working on it he said. We would like to stick graphene
Our microscopy facility at ORNL allows us to see materials in a way they've never been seen before--down to the level of individual atoms.
#Roman seawater concrete holds the secret to cutting carbon emissionsthe chemical secrets of a concrete Roman breakwater that has spent the last 2000 years submerged in the Mediterranean sea have been uncovered by an international team of researchers led by Paulo Monteiro of the U s
But making it releases carbon from burning fuel needed to heat a mix of limestone and clays to 1450 degrees Celsius (2642 degrees Fahrenheit)--and from the heated limestone (calcium carbonate) itself.
The lime was hydrated--incorporating water molecules into its structure --and reacted with the ash to cement the whole mixture together.
In concrete made with Portland cement this is a compound of calcium silicates and hydrates (C-S-H). Roman concrete produces a significantly different compound with added aluminum and less silicon.
The resulting calcium-aluminum-silicate-hydrate (C-a-S-H) is an exceptionally stable binder. At ALS beamlines 5. 3. 2. 1 and 5. 3. 2. 2 x-ray spectroscopy showed that the specific way the aluminum substitutes for silicon in the C-a-S-H
and less release of carbon into the atmosphere may be the legacy of a deeper understanding of how the Romans made their incomparable concrete.
and wine in the middle East and Mediterranean) as well as compounds deriving from pine tree resin. Herbal additives to the wine were identified also including rosemary basil and/or thyme
Alcoholic beverages in which resinous and herbal compounds are more easily put into solution were the principle medications of antiquity.
In four new studies of carbon isotopes in fossilized tooth enamel from scores of human ancestors and baboons in Africa from 4 million to 10000 years ago a team of two dozen researchers found a surprise
The isotope method cannot distinguish what parts of grasses and sedges human ancestors ate--leaves stems seeds and-or underground storage organs such as roots or rhizomes.
What You Eatthe new studies analyze carbon isotope results from 173 teeth from 11 species of hominins.
but the new studies include new carbon-isotope results for 104 teeth from 91 individuals of eight hominin species. Those teeth are in African museums
The method of determining ancient creatures'diets from carbon isotope data is less than 20 years old
The powder was placed in a mass spectrometer to learn ratios of carbon isotopes incorporated into tooth enamel via diet.
The ratios of rare carbon-13 to common carbon-12 reveal whether an animal ate plants that used so-called C3 C4
Animals eating C4 and CAM plants have enriched amounts of carbon-13. C3 plants include trees bushes and shrubs and their leaves and fruits;
Researchers at the Max Planck Institute for Chemical Ecology Jena Germany discovered that the ability of Manduca sexta moths to recognize changes in the profile of volatile compounds released by plants being attacked by Manduca caterpillars allows them to lay their eggs on plants that are less likely
but enzymes released by M. sexta caterpillars'spit change some of these molecules into (E)- 2-hexenyl acetate
Graphene consists of a single atomic layer of carbon arranged in a honeycomb lattice. Our first Science paper in 2008 studied the strength graphene can achieve
In its perfect crystalline form graphene (a one-atom-thick carbon layer) is the strongest material ever measured as the Columbia Engineering team reported in Science in 2008--so strong that as Hone observed it would take an elephant balanced on a pencil to break through a sheet
or ultrastrong composites that could replace carbon fiber. Or the researchers speculate a science fiction idea of a space elevator that could connect an orbiting satellite to Earth by a long cord that might consist of sheets of CVD graphene
since graphene (and its cousin material carbon nanotubes) is the only material with the high strength-to-weight ratio required for this kind of hypothetical application.
This is due to all the atoms in graphene being surface atoms so surface damage that would normally not degrade the strength of 3d materials can completely destroy the strength of 2d materials.
The bacterial diversity in the cloaca of each bird could be estimated with the aid of molecular genetic techniques.
#Dairys carbon footprint: Flatulence tops the listresearchers at the University of Arkansas are attempting to help the U s. dairy industry decrease its carbon footprint as concentrations of carbon dioxide in Earth's atmosphere reach record levels.
In 2007 Americans consumed approximately 17.4 million metric tons of fluid milk--milk consumed as a drink
Their study was published as a special issue Carbon and Water Footprint of U s. Milk From Farm to Table of the International Dairy Journal in April.
Lignin is the chemical compound that binds cellulose and hemicellulose together in plant cell walls. Commonly enzymes or chemicals are used to remove it from biomass
The Iowa State team replaced the initial steaming with ultrasound sonically smashing the corn into tiny particles in the same way physicians use ultrasound to shatter kidney stones.
To take the temperature of the past we rely on indirect evidence like oxygen isotope ratios in the fossil shells of marine organisms
#Land-based carbon offsets: False hope? Forest and soil carbon is important, but does not offset fossil fuel emissionsleading world climate change experts have thrown cold water on the idea that planting trees can offset carbon dioxide emissions from fossil fuels.
Professor Brendan Mackey of Griffith University Climate Change Response Program is the lead author of an international study involving researchers from Australia
and the U k. Their findings are reported in Untangling the confusion around land carbon science and climate change mitigation policy published in the scientific journal Nature Climate Change.
and internationally assume that fossil fuel emissions can be offset through sequestering carbon by planting trees and other land management practices.
There is a danger in believing that land carbon sinks can solve the problem of atmospheric carbon emissions
They easily outperform other cells with polymer compounds as active elements. The discovery is detailed online in the American Chemical Society journal Nano Letters.
but that's surprisingly better than other labs have achieved using polymer compounds. You need two components in a solar cell:
and neuroscience and director of the Institute for Genomic Biology at the University of Illinois. And finding that it's Egr with all that this gene is known to do in vertebrates provides another demonstration that some of the molecular mechanisms underlying behavioral plasticity
Derek Meyers a doctoral student in physics at the U of A found that the way electrons form in superconductive material--known as the Zhang-Rice singlet state--was present in a chemical compound that is very different
of emerging low-carbon technologies which have yet to be proven. Story Source: The above story is provided based on materials by American Chemical Society.
of emerging low-carbon technologies which have yet to be proven. Story Source: The above story is provided based on materials by American Chemical Society.
The amount of harmful fat particles in the blood also declined says Lieselotte Cloetens a biomedical nutrition researcher at Lund University.
The one-atom-thick form of carbon can act as a go-between that allows vertically aligned carbon nanotubes to grow on nearly anything.
when graphene is used as a middleman surfaces considered unusable as substrates for carbon nanotube growth now have the potential to do so.
By its very nature one-atom-thick graphene is all surface area. The same could be said of carbon nanotubes which are basically rolled-up tubes of graphene.
A vertically aligned forest of carbon nanotubes grown on diamond would disperse heat like a traditional heat sink but with millions of fins.
Such an ultrathin array could save space in small microprocessor-based devices. Further work along these lines could produce such structures as patterned nanotube arrays on diamond that could be utilized in electronic devices Ajayan said.
and hold the airborne iron-based catalyst particles from which the nanotubes grow. The researchers think graphene facilitates nanotube growth by keeping the catalyst particles from clumping.
Ajayan thinks the extreme thinness of graphene does the trick. In a previous study the Rice lab found graphene shows materials coated with graphene can get wet
whether the type of exposure such as whether the compound was inhaled or absorbed through the skin
Professor G. Eric Schaller the paper's senior author studies the molecular mechanisms by which a plant recognizes a hormone
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