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The combination of three measures to eradicate the Asian tiger mosquito, avoid standing water, use insecticides to kill larvae and adults, and clean the waste-land reduces its presence in the middle, as shown for the first time a study coordinated by researchers Autonomous University of Barcelona.
(Female Asian tiger mosquito ( Aedes albopictus ) . Image: CDC)
An experimental study conducted in Sant Cugat del Valles and Ruby, coordinated by scientists at the Autonomous University of Barcelona (UAB), has evaluated the efficiency of a set of complementary strategies in reducing the population of tiger mosquito ( Aedes albopictus ) , started in February 2008. The research is based on counting of eggs in small traps and experimental researchers have observed for the first time the number has declined to implement the measures.
Strategies included, first, a program of visits by a team of reporters to the homes of the affected areas, to explain preventive measures and avoid standing water to accumulate in the vessels’ home gardens and patios. Second, treatment with insecticides in sinks, water tanks and sewage, to remove the larvae, and vegetation of the parks and gardens, to eliminate adult insects. Finally, cleaning trash and debris on the land that could support the proliferation of mosquitoes.
During the visit program, researchers have inspected over 3,000 homes and interviewed nearly 700 people. To demonstrate the effectiveness of actions to deal with the tiger mosquito, has been counting the eggs laid by females in traps consisting of a few simple pieces of wood inside the small vessel of water. These traps reproduce the conditions of the trunks of trees where the mosquito was played originally in the Asian jungles.
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The anomalous behavior of ants, the researchers infected represents a sort of extension of the phenotype of the fungus
The ants of the tropical species Camponotus leonardi, Dweller of the time of the forests, are known for when they are infected with the parasitic fungus Ophiocordyceps unilateralis, Their behavior changes dramatically.
Now a study conducted by an international team of biologists has clarified some of the mechanisms of the fungus, which is illustrated in an article in the journal BMC Ecology.
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The helmet treehopper, cousins of cicadas, is not an outgrowth of the chest, but a third pair of wings changed significantly.
(The treehopper are distinguished by helmets of various shapes and surprising.)
How many wings has a ladybug? Four! Both are actually used for flight and two others are transformed into rigid elytra that protect the first two when folded (red hull with black dots). In this, the ladybug is consistent with the general plan of organization of insects: three parts (head, thorax and abdomen), two antennae, six legs and two pairs of wings at most, sometimes modified (pendulums in flies), or eliminated (in fleas and lice). We imagined this scheme must. This is not the case. Nicolas Gompel and Benjamin Prud’homme, Institute of Developmental Biology of Marseille-Luminy (CNRS / Université Aix-Marseille 2) showed, with their colleagues, that treehopper, cousins of the cicada, have three pairs of wings! Additional appendices are substantially transformed and helmets are to varied roles and the exuberant.
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The analysis of the bones of the thylacine shows that his style of hunting was more like that of felines that of other large canids
The thylacine – a marsupial carnivore in the last one, called “Benjamin”, died in Hobart Zoo in 1936 – had his head and body similar to those of a dog, the coat more like that of a cat, carrying young in a pouch like kangaroos. Not surprisingly, the common names of this marsupial that once inhabited Australia and Tasmania were somewhat contradictory: some called marsupial wolf, Tasmanian tiger others.
Research published on the Biology Letters to the conclusion that, if you want to make comparisons between similar specimens of different taxonomic groups as well, then the thylacine had more in common with the tiger with the wolf.
His style of hunting, it is clear from the research, was lonely and ambush, different from that of wolves or other large canids that hunt in groups and cover small distances during the hunt.
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The study of different types of lignin and the different modes of production by the plants could allow more efficient use of biomass
Crucial information for a possible shift in production from biomass biocombiustibili was discovered by sequencing the DNA of the plant species of Selaginella moellendorffii .
“When we burn coal, burn the ancestors of Selaginella , “said Jody Banks, Purdue University botanist who first proposed to the Joint Genome Institute (JGI) of the United States Department of Energy (DOE) sequencing of the plant as part of the scientific program of 2005.
As explained by Igor Grigoriev, senior author of the study, published online in Science Express , the genome of Selaginella fills a huge gap in the evolution of plants among the green alga Chlamydomonas , sequenced by JGI in 2007, and angiosperms with the vascular system.
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Researchers have highlighted the role of tensile forces in the cohesion of cells in a tissue.
Tissue consists of cells that are coordinated to give it its biological function (muscle contractility, for example). Several types of interaction contribute to the organization of cells, and if we can study these forces on a few isolated cells, it is more difficult to assess in a cluster of several thousand cells. Jeffrey Morgan and his team at Brown University in Rhode Island, presented an original method for measuring the energy supplied by an assembly of cells.
In their experiment, approximately 20 000 cells fill a trough circular one millimeter in diameter, which passes around a cone made of plastic on which the cells do not stick: they are binding only between them, thus forming a torus about 100 micrometers in diameter. Cells exert tension forces on their neighbors and attract them, so that the torus shrinks. Constrained by the geometry of the torus moves up the cone to reach a stable state, where cells are organized. The power generated by the cells to resist gravity is evaluated according to the ascent of the torus.
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Some security mechanisms and folding of DNA have been clarified by a study that highlighted the key role of nuclear aggregates of polyamines
Some security mechanisms and folding of DNA and, therefore, the relationship between its structure and its function, have been clarified by a study by researchers at the Institute of Food Sciences, CNR, Avellino, in collaboration with the University of Foggia and Genoa, now published in the journal Biomacromolecules.
While the usual genome studies seek to explain their operations by studying the sequence, the new work has focused on issues related to the shape of DNA itself, believing that could affect numerous cellular functions, such as ontogeny, cellular homeostasis, up to development of pathological conditions.
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The fat cells around breast tumors promote the spread of cancer cells.
Breast cancer is most common among women, which affects about 1000 women each year. All cancers do not progress the same way, according to the tumor characteristics and risk factors. We recently showed that obesity was a negative factor, obese women have a higher risk of spread of cancer cells. What is the relationship between the development of cancer and obesity? Teams Catherine Muller and Philippe Valet, University Paul Sabatier in Toulouse, have shown that fat cells, or adipocytes, present around the tumors in the breast promotes the spread of cancer cells.
Breast cancer is a malignant tumor of the mammary gland. This includes 15 to 20 lobes that secrete milk, separated by adipose tissue. Cancer arises from these lobes surrounded by fat cells. By culturing in the laboratory of tumor cells with adipocytes, biologists have shown that cancer cells have invasive characteristics when they were in the presence of adipocytes. In other words, they metastasize. In addition, under these conditions, adipocytes phenotypes (aspects) including individuals and secrete proinflammatory factors, such as interleukin 6. Moreover, vitroThis molecule alone is sufficient to render metastatic cancer cells.
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The efficiency was increased to almost total blockade of tumor growth when leflunomide was administered in combination with PLX4720
Leflunomide, a drug widely used for the treatment of rheumatoid arthritis, is effective in inhibiting the development of melanoma: what is announced on the pages of the journal Nature researchers at the University of East Anglia (UEA) and the Children’s Hospital in Boston, coordinated by Grant Wheeler and Matt Tomlinson.
As you know, melanoma is a cancer that affects the pigment cells of the skin and is the most aggressive form of cancer among the skin. Unlike other cancers, its incidence is increasing. If diagnosed early, the tumor is surgically removed safely, but if it has already given rise to metastases, the prognosis is often poor.
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A Japanese research supports the so-called “doublesex hypothesis” that a specific gene family constitutes the common basis of the mechanisms of sexual differentiation throughout the animal kingdom
A significant connection between the molecular mechanisms underlying the genetic and environmental sex determination was discovered by a team of researchers at Osaka University and the National Institute for Basic Biology, which report in an article published in the journal online Public Access PLoS Geneticss.
The ways in which sex is determined by a specific individual will vary depending dela animal species and can be divided into two broad categories, that of determining the genetic and environmental determination. In the first sexual differentiation comes from intrinsic genetic differences between males and females, while in the second it depends on a number of environmental signals. These mechanisms, however, have not yet been fully clarified.
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(Female Asian tiger mosquito ( Aedes albopictus ) . Image: CDC)
(The treehopper are distinguished by helmets of various shapes and surprising.)
Tissue consists of cells that are coordinated to give it its biological function (muscle contractility, for example). Several types of interaction contribute to the organization of cells, and if we can study these forces on a few isolated cells, it is more difficult to assess in a cluster of several thousand cells. Jeffrey Morgan and his team at Brown University in Rhode Island, presented an original method for measuring the energy supplied by an assembly of cells.