Magnetocaloric effect Gd(Ni0.99Fe0.12)2

This work has been supported by the State contracts No. 1362 between UrFU and the Ministry of Education and Science of Russian Federation and by the Fund of assistance to development of small forms enterprises in scientific-technical sphere No. 6576GU/2015

Proton magnetic resonance spectroscopy of neurometabo­lites in the hippocampi of aggressive and tame male rats

Proportions of major neurometabolites with regard to their total amount in the dorsal region of the hippocampus were studied in adult male rats of populations selected for long for increase and absence of aggressivefearful response to humans and in unselected vivarium- kept rats by 1H magnetic resonance spectrometry. Tame and unselected males showed no significant differences in the proportions of any neurometabolites studied. Differences in the proportions of some neurometabolites were found in aggressive vs. tame and in aggressive vs. unselected animals. Tame animals showed higher pro­portions of GABA, N-acetylaspartate (NAA), and choline derivatives and a lower proportion of phosphoryl­ethanolamine than aggressive ones. It is likely that the elevated content of GABA, one of the main inhibitory neurotransmitters in the brain, lowers excita­tion intensity in tame pups in comparison to aggressive ones. In comparison to unselected animals, aggressive rats demonstrated higher proportions of glutamine, aspartate, phosphorylethanolamine, and lactate and lower proportions of NAA and creatinine+ phosphocreatinine. Aspartate is one of the main excitement transmitter, and its elevated proportion in the brain of aggressive rats may favor more intense excitation than in unselected rats. In contrast, the elevated proportion of glutamine in aggressive rats vs. tame rats may be indicative of (1) a metabolic disturbance in the glutamate–glutamine cycle, which links neural and glial cells, and (2) decrease in the activity of glutaminase, the enzyme converting glutamine to glutamate (GABA precursor). The reduced NAA proportion together with the elevated proportion of glutamine in aggressive rats point to impaired energy metabolism in comparison to unselected animals. The differences in neurometabolite patterns between hippocampi of male rats of the unselec­ted and aggressive populations suggest the existence of different neurobiological mechanisms governing aggression manifestation

Silica in Protoplanetary Disks

Mid-infrared spectra of a few T Tauri stars (TTS) taken with the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope show prominent narrow emission features indicating silica (crystalline silicon dioxide). Silica is not a major constituent of the interstellar medium; therefore, any silica present in the circumstellar protoplanetary disks of TTS must be largely the result of processing of primitive dust material in the disks surrouding these stars. We model the silica emission features in our spectra using the opacities of various polymorphs of silica and their amorphous versions computed from earth-based laboratory measurements. This modeling indicates that the two polymorphs of silica, tridymite and cristobalite, which form at successively higher temperatures and low pressures, are the dominant forms of silica in the TTS of our sample. These high temperature, low pressure polymorphs of silica present in protoplanetary disks are consistent with a grain composed mostly of tridymite named Ada found in the cometary dust samples collected from the STARDUST mission to Comet 81P/Wild 2. The silica in these protoplanetary disks may arise from incongruent melting of enstatite or from incongruent melting of amorphous pyroxene, the latter being analogous to the former. The high temperatures of 1200K-1300K and rapid cooling required to crystallize tridymite or cristobalite set constraints on the mechanisms that could have formed the silica in these protoplanetary disks, suggestive of processing of these grains during the transient heating events hypothesized to create chondrules.Comment: 47 pages, 9 figures, to appear in the 1 January, 2009 issue of the Astrophysical Journa

Effects of neonatal handling on behavior and stress-response in rats selected for reaction towards humans

It is known that neonatal handling may cause longterm changes in neurobiological and behavioral phenotypes. Neonatal handling of rats selected for enhanced aggressiveness towards humans (“aggressive” rats of generation 44) significantly mitigated aggression and stress responsiveness. However, levels of corticosterone in stress in intact aggressive rats of later generations (70s) were lower than in generation 44, which differed little from the corresponding value in “tame” rats, selected in the opposite direction, for the absence of aggressiveness towards humans. The study was conducted with Norway rat populations of the 75th generation of selection for aggressive and tame behavior, respectively. The goal was to find out whether the decrease in stress response in aggressive rats at the current stage of selection was accompanied by a decrease in the influence of handling on aggressiveness. It was found that neonatal handling of aggressive animals caused a significant decrease in aggressiveness, although considerably smaller than in generation 44. In both aggressive and tame rats, the blood corticosterone level at stress was getting back to the basal level for a longer time than in the corresponding control groups. Neonatal handling decreased the amount of mRNA for the glucocorticoid receptor (GR) in the hippocampus of aggressive rats but did not affect significantly the amount of mRNA for the corticotropin-releasing hormone (CRH) in the hypothalamus. However, higher contents of CRH mRNA were recorded in aggressive rats than in tame ones in the control groups. However, no differences in glucocorticoid receptor mRNA  were found between the strains in contrast to earlier generations. It was shown that neonatal handling was beneficial for maternal behavior in tame rats. Thus, the results obtained in the 75th generation of selection indicate that the effect of handling on aggressiveness weakens with decreasing stress responsiveness in aggressive rats. This is likely to be related to the changing amount of GR in the hippocampus and stronger glucocorticoidmediated feedback at the current stage of selection. The minor prolongation of the stress response appears to be related to the stressing component of neonatal handling rather than to changes in maternal care

Geo-spatial Hotspots of Hemorrhagic Fever with Renal Syndrome and Genetic Characterization of Seoul Variants in Beijing, China

Hemorrhagic fever with renal syndrome (HFRS) is caused by Hantaviruses, the enzootic viruses with a worldwide distribution. In China, HFRS is a significant public health problem with more than 10,000 human cases reported annually and the endemic areas of the disease have extended from rural to urban areas and even to central cities in recent years. The HFRS incidence has increased recently and the morbidity seemed to be considerably diverse in different areas in Beijing, the capital of China. With the aim of gaining more information to control this disease, we carried out a spatial analysis of HFRS based on the data from human cases during 2004–2006 and investigated the genetic features of complete S and partial L segment sequences of Seoul virus from natural infected rodent hosts and patients. We found three geo-spatial clusters, i.e., “hotspots” of HFRS in Beijing, where intervention should be enhanced. Our data indicated that the genetic variation and recombination of SEOV might be related to the high risk areas of HFRS in Beijing, which was worthy of further investigation

Enhanced Longevity by Ibuprofen, Conserved in Multiple Species, Occurs in Yeast through Inhibition of Tryptophan Import

The common non-steroidal anti-inflammatory drug ibuprofen has been associated with a reduced risk of some age-related pathologies. However, a general pro-longevity role for ibuprofen and its mechanistic basis remains unclear. Here we show that ibuprofen increased the lifespan of Saccharomyces cerevisiae, Caenorhabditis elegans and Drosophila melanogaster, indicative of conserved eukaryotic longevity effects. Studies in yeast indicate that ibuprofen destabilizes the Tat2p permease and inhibits tryptophan uptake. Loss of Tat2p increased replicative lifespan (RLS), but ibuprofen did not increase RLS when Tat2p was stabilized or in an already long-lived strain background impaired for aromatic amino acid uptake. Concomitant with lifespan extension, ibuprofen moderately reduced cell size at birth, leading to a delay in the G1 phase of the cell cycle. Similar changes in cell cycle progression were evident in a large dataset of replicatively long-lived yeast deletion strains. These results point to fundamental cell cycle signatures linked with longevity, implicate aromatic amino acid import in aging and identify a largely safe drug that extends lifespan across different kingdoms of life.The open access fee for this work was funded through the Texas A&M University Open Access to Knowledge (OAK) Fund

Quartz and opaline silica in ocean sediments

A new method of quantitative analysis of quartz and opal in bottom sediments is developed. It is based on the study of sediment samples in form of suspensions in petrolatum where potassium rhodanate is added as an internal standard