New research by neuroscientists at Cold Spring Harbor Laboratory (CSHL) published in The Journal of Neuroscience reveals a set of cells in the fruit fly brain that respond specifically to food odors.
when the fly is presented different food odors--apple mango banana--predicts incredibly well how much the flies will given'like'a odor says the lead author of the research paper Jennifer Beshel Ph d. a postdoctoral investigator in the laboratory of CSHL
when flies were hungry. The amplitude of their response could in fact predict with great accuracy how much the flies would like a given food odor--i e. move toward it;
the scientists needed simply to look at the responses of the dnpf-expressing neurons. When they switched off these neurons the researchers were able to make flies treat their most favored odor
as if it were just air. Conversely if they remotely turned these neurons on they could make flies suddenly approach odors they previously had tried to avoid.
As Dr. Beshel explains: The more general idea is that there are areas in the brain that might be involved specifically in saying:'
#Scientists find soaring variety of malaria parasites in batsresearchers have discovered a surprising diversity of malaria parasites in West african bats as well as new evidence of evolutionary jumps to rodent hosts.
and the Museum fuì r Naturkunde Berlin the new study reveals that two bat-infecting parasites are closely related to parasites in rodents that are used commonly to model human malaria in laboratory studies.
Bats which are important reservoir hosts for many pathogens particularly viruses have been hosts to malaria parasites for more than a century said coauthor Susan Perkins an associate curator in the Museum's Division of Invertebrate Zoology.
Understanding the evolution of malaria parasites in bats and other animals and how they fit into the tree of life is key to understanding this important human disease.
Malaria is caused by a handful of species of parasites in the Genus plasmodium through the bite of mosquitos
Experimental research on drugs immunology and the development of malaria is done typically on related Plasmodium species that infect rodents including laboratory-reared mice.
They found a vast diversity of malaria parasites that included not just theplasmodium species but also members of three other genera.
The DNA from several genes of the bat parasites was sequenced at the Museum's Sackler Institute for Comparative Genomics resulting in the most comprehensive evolutionary tree of life for malaria parasites of bats to date.
The authors report that two parasites Plasmodium voltaicum and Plasmodium cyclopsi show patterns of evolutionary jumps from the rodent lineage into bats and then likely a reverse jump with a bat parasite reinfecting rodent hosts.
The authors suggest that the bat hosts which roost in trees may have been exposed to the same mosquito vectors that transfer the parasites between the tree-dwelling rodent hosts.
It is unknown what the physiological effects of the parasites are on the bats but the high diversity of parasites as well as the high proportion of individuals that are infected with the parasites suggest that this may be yet another example of the unusually high tolerance of these flying mammals for pathogens said co-author Juliane Schaer a researcher at the Max Planck Institute
for Infection Biology and the Museum fuì r Naturkunde Berlin. Other work has suggested that the evolution of flight may have triggered parallel strengthening of the immune system of bats
and may explain why they are able to host viruses such as Ebola rabies and the recently discovered Middle east Respiratory system (MERS) virus
which are highly pathogenic to other mammals including humans. Story Source: The above story is provided based on materials by American Museum of Natural history.
and mites--mainly amitraz ivermectins and pyrethroids but ticks have become increasingly resistant to these treatments.
The global cost of the tick-borne diseases and associated acaricide application is estimated to be more than £4 billion annually.
Resistance to all the main acaricides is documented well--for example amitraz resistance is seen in about 20%of Australian tick populations and more than 50%of Mexican ticks.
and laboratory populations of ticks to test the effectiveness of resistance management strategies. The study was conducted on cattle at the University of Queensland's Pinjarra Hills Campus in Australia where the impact of ticks
and treatments to control them costs £120 million per annum. Prof Jonsson added: There are many theories as to how acaricide resistance can be delayed
and using tick-resistant cattle might all delay the development of resistance. However without empirical studies to test the value of the management strategies it is really impossible to provide evidence-based recommendations to farmers.
and signaling molecule in both plants and animals and plays an important role in root system formation.
Our research provides important insights to the biology of pollinators said co-author Professor Vincent Jansen.
The research was funded as part of the £10 million'Insect Pollinators Initiative'setup to understand the causes of pollinator declines
and safer for farm workerssince 1996 corn containing a gene that allows it to create a protein that is toxic to certain insects yet safe for human consumption has been grown in the United states
Although varieties of sweet corn (corn on the cob) have existed since the late 1990s relatively few acres have been planted.
and there will be less risk to nontarget organisms including natural enemies that help suppress pest densities.
The study Multi-State Trials of Bt Sweet corn Varieties for Control of the Corn earworm (Lepidoptera:
Noctuidae) analyzed the performance of Bt sweet corn comparing its rate of infestation and marketability to genetically identical varieties that lacked Bt proteins.
and Georgia locations that differ in climate management practices and pest pressure. The authors found that for pest management of the corn earworm Bt sweet corn consistently performed better than its non-Bt counterparts even those that were sprayed with conventional insecticides.
Across multiple states and multiple years Bt sweet corn performed better and required fewer sprays to meet market standards said Cornell entomology professor Anthony Shelton.
The authors predict that growers could realize increased profits with Bt sweet corn because of lower inputs and higher marketability while simultaneously conserving populations of beneficial insects that keep damaging pests at bay.
In wild strawberries it also serves to lure the animals which the plant exploits to spread its seeds.
When birds and small mammals feed on the fruit they subsequently excrete the indigestible seeds elsewhere
Moreover the developing fruit also has to contend with the attentions of pathogens and pests.
These compounds help to protect the developing fruit against predators pathogens and abiotic stresses. When the seeds are ripe the Anr gene is turned off.
because the timing of the switch between warding off pests and the initiation of pigmentation not only controls the quality of the fruit it also determines the level of pesticide use.
Famous weevils moths and borer beetles live in a very comfortable environment when in the middle of a silo or warehouse fill with grains.
This insects alongside some fungi bacteria and viruses cause annual loses of between four and ten percent of all the stored grains worldwide mainly corn wheat sorghum rice and beans.
Until five years ago the main fumigation technique and pest control inside warehouses and silos was the use of chemical substances such as aluminum phosphide and methyl bromide
The ozone removes the comfort zone of the insects making them unable to breathe and modifying the internal atmosphere of the room using this technique pest free grains are obtained during the whole purchase sale and storage cycle.
The effectiveness of this technology meets the Official Mexican Standard (NOM. This innovation already has industrial property protection
and activity of microorganisms in the soil which form complex biological communities involving plants and animals.
and can even be deposited atmospherically on the hive itself said Kristen Hladun the lead author of the study and a postdoctoral entomologist.
in order to mimic the chronic exposure this insect may face when foraging in a contaminated area.
The honey bee is an important agricultural pollinator in the United states and throughout the world.
Low Se concentrations are beneficial to many animals; in particular it is a critical component of an antioxidant enzyme.
Several insect species suffer toxic effects from feeding on Se-contaminated food. In the case of the honey bee Se enters the body through ingestion of contaminated pollen and nectar.
It is not clear how selenium damages the insect's internal organs or if the bee has the ability to detoxify these compounds at all Hladun said.
Hladun explained that honey bees may also be more susceptible than other insects due to a lack of detoxification enzymes that other insects still possess.
Further honey bees at the larval stage are more susceptible to selenium relative to other insect species. Mortality within the hive can reduce the number of workers
Honey bees are social animals and their first line of defense against environmental stressors is the foraging bees themselves.
According to Hladun knowing which contaminants are the most important to regulate is key to minimizing the exposure of honey bee hives to contaminants.
or to move hives away from contaminated areas she said. Also better management of weedy plant species that are known to be Se-accumulators can prevent them from becoming a route of exposure.
and lead in particular) that have been found in honey bee hives especially the ones located near urban or industrial areas.
and to dust mites. There are two treatments one for grass allergy which is commonly known as hay fever and the other for dust mite allergy.
They are expected to be helpful for the millions of people who as a reaction to grass pollen
or the tiny bugs that live in house dust have sneezing itching eyes and a running nose that often significantly impacts their productivity at school or work.
Between 15 and 25 per cent of the population in North america and Europe is sensitive to pollen from different grass species. One in four people is sensitized to house dust mites more than any other common allergen
During the clinical trial for the dust mite treatment 172 patients who received four doses of the treatment over 12 weeks had improved significantly allergy symptoms a year after the start of treatment compared to patients who received a placebo.
Positive results first with a cat allergy therapy and now with house dust mite and grass allergy treatments suggest that this approach may be used for many common allergies.
Dust mites are close relatives of spiders and ticks and are too small to see without a microscope.
They eat skin cells shed by people and they thrive in warm humid environments. Upholstered furniture bedding
and carpeting provide an ideal environment for dust mites. Story Source: The above story is provided based on materials by Mcmaster University.
First kind of study in the worldas pigs are a well-known animal model for studying human obesity because of similar genomes
and eating behaviour observations on all pigs via genome wide association studies to detect eating behaviour genes--a big task equivalent to finding polar bears in a snowstorm says Kadarmideen.
#Fear of predators drives honey bees away from good food sourcesmost of us think of honey bees as having a bucolic pastoral existence--flying from flower to flower to collect the nectar they then turn into honey.
which predators seize them from the sky and wait to ambush them on flowers. Such fear drives bees to avoid food sources closely associated with predators
and interestingly makes colonies of bees less risk-tolerant than individual bees according to a study published in this week's issue of the open-access journal PLOS ONE.
-looking Asian Giant hornet Vespa tropica and a smaller hornet species known as Vespa velutina which has invaded Europe
and now poses a threat to European honey bees. The Asian Giant hornets are armored dangerous heavily predators says Ken Tan the first author of the paper who also works at the Chinese Academy of Science's Xishuangbanna Tropical Botanical Garden.
Bee colonies respond by forming balls of defending bees encasing the hornet and in some cases cooking it to death with heat generated by the bees.
The researchers found that bees treated the bigger hornet species which is four times more massive than the smaller species as more dangerous.
In a series of experiments they presented bees with different combinations of safe and dangerous feeders--depending on their association with the larger
or smaller hornets--containing varying concentrations of sucrose. Bees avoided the dangerous feeders and preferred feeders that provided sweeter nectar says Nieh.
However predators are clever and can focus on sweeter food ones which bees prefer. So we also tested how bees would respond
They avoided the giant hornet at the best food but continued to visit the lower quality food with the smaller hornet.
Other scientists involved in the research were Zongwen Hu Weiwen Chen Zhengwei Wang and Yuchong Wang all of the Eastern Bee Research Institute of Yunnan Agricultural University.
Scientists find insect DEET receptors, develop safe alternatives to DEETINSECTS are repelled by NN-diethyl-m-toluamide also known as DEET.
But exactly which olfactory receptors insects use to sense DEET has eluded scientists for long. Now researchers at the University of California Riverside have identified these DEET-detecting olfactory receptors that cause the repellency--a major breakthrough in the field of olfaction.
which olfactory receptor insects used to avoid DEET said Anandasankar Ray an associate professor of entomology who led the research team.
The method Ray's team used to identify the receptors examined in an unbiased fashion all the sensory neurons in the insect
In their experiments the researchers used the genetic model system Drosophila melanogaster (fruit fly) that was engineered genetically in such a way that neurons activated by DEET glowed fluorescent green.
because the receptor in insects for DEET was unknown. Capable of dissolving plastics and nylon DEET has been reported to inhibit an enzyme (acetylcholinesterase) in mammals that is important in the nervous system.
DEET is also unaffordable and inconvenient for use in Africa and other parts of the world where hundreds of millions of people suffer from insect-transmitted diseases.
Our three compounds which we tested rigorously in the lab do not dissolve plastics Ray said.
But now they can be applied to bed-nets clothes curtains--making them ward off insects. Using novel chemical informatics strategies Ray's lab screened half a million compounds against the DEET receptor to identify substitutes.
not only to be strong repellents but also found naturally in fruits plants or animals. The algorithm predicted nearly 200 natural DEET substitutes;
Of these eight were strong repellents on flies of which four were tested in Aedes mosquitoes and found to be strong repellents.
Of the four compounds three are approved already by the Food and Drug Administration as food additives.
All three compounds activated the same antennal cells in flies as DEET Ray said. What's really encouraging is that some of these compounds may be affordable to produce in large quantities.
In past work his lab identified compounds that mask the host from insects as well as compounds that serve as lures.
The lab's new research has given us compounds that serve as repellents making possible safe alternatives to DEET for a variety of applications including control of mosquitoes flies and possibly lice bed bugs ants cockroaches grain pests and agricultural pests.
Ir40a and its related proteins are conserved not only in flies and mosquitoes but also in many other insects that are human
and plant pests Ray explained. Our findings could lead to a new generation of cheap affordable repellents that could protect humans animals and in the future our crops as well.
He was joined in the study by UCR's Pinky Kain (co-first author who found the receptor) former graduate student Sean Michael Boyle (co-first author who identified the substitutes) Sana Khalid Tharadra
Tom Guda Christine Pham and Anupama Dahanukar. The three natural compounds identified by Ray's group that mimic DEET are methyl NN-dimethyl anthranilate ethyl anthranilate and butyl anthranilate.
Specifically the researchers used their computational approach to study the interactions between 24 odorant receptors in Drosophila antennae
They then tested their predictions for some receptors on living flies and found that approximately 71 percent of the predicted compounds activated
The pollen's structure suggests that the plants were pollinated by insects: most likely beetles as bees would not evolve for another 100 million years.
Story Source: The above story is provided based on materials by University of Zurich. Note: Materials may be edited for content and length.
#Caribou may be affected indirectly by sea-ice loss in the Arcticmelting sea ice in the Arctic may be leading indirectly to fewer caribou calf births and higher calf mortality in Greenland according to scientists at Penn State university.
which in turn is associated with lower production of calves by caribou in the area. The results of the study will be published in the journal Nature Communications on 1 october 2013.
Post began his observations on the relationship between the timing of caribou calving and the start of the plant-growing season in Greenland 20 years ago.
Post added that as his observations have continued the data have revealed an increasingly earlier start to the plant growing season a change that has not been matched by correspondingly earlier calving by caribou in the area.
Kerby added that archeological evidence suggests that caribou have used this area as a calving site for over 3000 years.
In late May to early June caribou typically arrive from their west-to-east migratory journey in search of young plants to eat around the time caribou give birth.
by the time the hungry caribou arrive to eat them Kerby said. The animals show up expecting a food bonanza
but they find that the cafeteria already has closed. The team members explained that while plants respond to warmer temperatures
and other changes in climate simply by adjusting the timing of their growth caribou --whose reproductive cycles are timed by seasonal changes in daylight length rather than by temperature--continue to give birth at nearly the same time during the spring
and the timing of when animals are most dependent on them for nutrition Kerby said. In addition to analyzing their own data Post and Kerby also used information from a 1970s study of caribou calving and calf survival at the same site by Danish biologists Henning Thing and Bjarne Clausen.
This comparison allowed us to look for signs of trophic mismatch in the same caribou population over 30 years ago Post said.
He explained that he and Kerby used the statistically robust relationship between sea ice and the timing of plant growth to hindcast trophic mismatch to 1979
We found an interesting contrast to the current state of caribou calving in relation to spring green-up Post said.
Sea ice is part of a broader climate system that clearly has important effects on both plants and animals.
and found that aflatoxins are present in chicken breast gizzard liver and eggs-white and yolk.
and/or an antidepressant would help reduce them in men as it does in many women said Mara Vitolins Dr. P. H. professor of public health sciences at Wake Forest Baptist
Vitamin B3--also known as niacin--and its metabolite nicotinamide in the worms'diet caused them to live for about one tenth longer than usual.
This worm which is merely one millimetre in length can be maintained easily and has a lifespan of only a month making it the ideal model organism for ageing research.
Whether niacin has similar effects on the life expectancy of mice is the subject of Ristow's current research.
The United states created stronger regulations for tobacco advertising in the 1990s after similar research found that six year olds were as familiar with Camel tobacco's Joe Camel mascot as with the Disney Channel's Mickey mouse.
The disease is caused by a parasite that enters the animals'blood as a result of the bite of the Tsetse fly.
Of over 350 animals tested 41 were found to be infected. Zebus were infected twice as often as Baoul s or hybrid cattle.
We only studied healthy animals and Zebus with such high parasite levels would have been too ill to be included in our study says Silbermayr.
The theory describes how dust grains in interstellar space like soldiers in lock-drill formation spin
In a study spanning two decades the researchers witnessed the near-complete extinction of native small mammals on forest islands created by a large hydroelectric reservoir in Thailand.
However the researchers saw native small mammals vanish with alarming speed with just a handful remaining--on average less than one individual per island--after 25 years.
Native mammals suffered the harmful effects of population isolation and they also had to deal with a devastating invader--the Malayan field rat.
In just a few years the invading rat grew so abundant on the islands that it virtually displaced all native small mammals.
The field rat normally favors villages and agricultural lands but will also invade disturbed forests.
This tells us that the double whammy of habitat fragmentation and invading species can be fatal for native wildlife said Lynam.
and the bacteria are resistant to being grown in the laboratory the only option for halting transmission of citrus greening has been to apply chemical pesticides to control the insect that spreads the bacteria Dandekar said.
These bacteria are carried from tree to tree by two species of the citrus psyllid a winged insect that is about one-eighth inch long
As the citrus psyllid feeds on a leaf it can pick up the bacteria from a diseased tree
However the citrus psyllid that transmits the bacteria was first found in California in 2008
Changes among the plants can be seen as they respond to cabbage white butterfly caterpillars and stinkbugs introduced during the experiment.
#Model to study human response to bacteria that cause peptic ulcers developedresearchers at the Virginia Bioinformatics Institute at Virginia Tech have developed a new large animal model to study how the immune system interacts with the stomach bacterium Helicobacter pylori the leading
Scientists did not observe an increase in CD8+T cells in mouse and gerbil models of H. pylori infection.
However the rise of the cells in pigs mirrors the recent findings in human clinical studies.#
#oepigs have greater anatomic physiologic and immunologic similarities to humans than mice the main animal model used in biomedical research said Raquel Hontecillas co-director of the Nutritional Immunology and Molecular Medicine
#A day in the life of the mysterious odd-clawed spider Progradungula otwayensisa recent paper published in the open access journal Zookeys provides a first time glimpse in the natural history of the enigmatic spider species Progradungula otwayensis.
Lurking in the hollows of old myrtle beech trees and thus hard to collect this extraordinary spider is an endemic species confined strictly to the beautiful Great Otway National park (Victoria Australia.
P. otwayensis belongs to the small spider family Gradungulidae which consists of seven genera with a total of 16 described species found exclusively in eastern Australia and New zealand.
The fibers are so small in diameter that prey insects easily become entangled in them without any glue needed.
which will be caught by using the ladder as a trap--a behavior which was described already in detail by now retired arachnologist Mike gray (Australian Museum) for the only known other species of this genus P. carraensis.
A single thick and shiny silk thread is used then by the spiders to provide a zip-line like connection between the external webs and the security of the enigmatic retreat in the hollows of ancient myrtle beech and mountain ash tree.
and Museum of the University of Greifswald (Germany) about the unusual bit of luck to have a glimpse into the secluded retreats of the spiders.
The unusual living habits and high degree of endemicity makes this spider a rare and remarkable species. The new study suggests that this spider is dependent on the microclimate in the hollows of old myrtle beech trees
(and less runoff) encourages predators of harmful animals minimizes greenhouse gas emissions improves job satisfaction for farm workers reduces injury
and stress in animals improves welfare and encourages biodiversity using native shrubs and trees. Additionally shrubs and trees with edible leaves and shoots along with pasture plants produce more food for animals per unit area of land than pasture plants alone.
Trees and shrubs have added the benefit of providing shade from hot sun and shelter from rain.
It also reduces stress by enabling the animals to hide from perceived danger. The planting as forage plants of both shrubs
and small branches can be consumed by farmed animals can transform the prospects of obtaining sustainable animal production said Professor Broom.
When ruminants such as cows goats and sheep are consuming the plants from a silvopastoral system researchers have seen an increase in growth and milk production.
As the numbers of animals per hectare was much greater production of good quality milk per hectare was four to five times greater on the silvopastoral system.
The paper'Sustainable efficient livestock production with high biodiversity and good welfare for animals'will be published in the 25 september edition of Proceedings of the Royal Society B. Story Source:
but also increases its presence in thin animals used as a control group.''Beige fat'cells are found in scattered lentil-sized deposits beneath the inguinal skin in obese diabetic Zucker rats.
Melatonin is a natural hormone segregated by the human body itself and melatonin levels generally increase in the dark at night.
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