Sequential alterations of glucocorticoid receptors in the hippocampus of STZ-treated type 1 diabetic rats

Type 1 diabetes is a common metabolic disorder accompanied by increased blood glucose levels along with glucocorticoid and cognitive deficits. The disease is also thought to be associated with environmental changes in brain and constantly induces oxidative stress in patients. Therefore, glucocorticoid-mediated negative feedback mechanisms involving the glucocorticoid receptor (GR) binding site are very important to understand the development of this disease. Many researchers have used streptozotocin (STZ)-treated diabetic animals to study changes in GR expression in the brain. However, few scientists have evaluated the hyperglycemic period following STZ exposure. In the present study, we found GR expression in the hippocampus varied based on the period after STZ administration for up to 4 weeks. We performed immunohistochemistry and Western blotting to validate the sequential alterations of GR expression in the hippocampus of STZ-treated type 1 diabetic rats. GR protein expression increased significantly until week 3 but decreased at week 4 following STZ administration. GR expression after 70 mg/kg STZ administration was highest at 3 weeks post-treatment and decreased thereafter. Although STZ-induced increase in GR expression in diabetic animals has been described, our data indicate that researchers should consider the sequential GR expression changes during the hyperglycemic period following STZ exposure.     

Equatorial X-ray Emissions: Implications for Jupiter's High Exospheric Temperatures

Observations with the High Resolution Imager on the Rontgensatellit reveal x-ray emissions from Jupiter's equatorial latitudes. The observed emissions probably result from the precipitation of energetic (>300 kiloelectron volts per atomic mass unit) sulfur and oxygen ions out of Jupiter's inner radiation belt. Model calculations of the energy deposition by such heavy ion precipitation and of the resulting atmospheric heating rates indicate that this energy source can contribute to the high exospheric temperatures(>800 kelvin at 0.01 microbar) measured by the Galileo probe's Atmospheric Structure Instrument. Low-latitude energetic particle precipitation must therefore be considered, in addition to other proposed mechanisms such as gravity waves and soft electron precipitation, as an important source of heat for Jupiter's thermosphere.     

Microscopic Particle Motions in Strongly Coupled Dusty Plasmas

The microscopic particle motions from the crystal to the disordered state of a dusty plasma with micrometer-sized silicon dioxide particle suspensions in a radio-frequency glow discharge system were studied through an optical microimaging system. Small-amplitude random motion around the lattice sites of the crystal state, relative domain motion with varying boundaries, cooperative hopping in the liquid state, and highly disordered motion with increasing radio-frequency power were observed. Chaotic states with different spatial scales under the coherent and stochastic coupling between dust particles and self-organized background plasma fluctuations were also demonstrated.     

Case studies on breeding systems and its consequences for germplasm conservation

The first results of a study relative to the demography of wild Lima bean (Phaseolus lunatus L.) populations in the Central Valley of Costa Rica are presented. Six wild populations were selected in the four mainly representative ecological zones of this region and several 1 m₂ quadrats were demarcated in order to determine the vital rates (fecundity, survival, growth and mortality) of the individuals within each population. These data were collected during two years from 3000 labelled individuals and combined with those relative to the soil seed bank and the seed dormancy to propose a demographic model for a hypothetical mean wild population based on the projection matrix theory. This model helps to determine the growth rate of the population, the stability of its structure and, by using a sensitivity analysis, reveals also the factors most constraining for the population survival. Population behaviour under natural conditions and human pressure are simulated, which allow to propose management practices for in situ conservation.     

籼型水稻短日低温不育核不育系go543S的选育研究

ｇｏ５４３Ｓ在遗传分类上属籼型水稻短日低温光温敏核不育系。育性转换的临界温度较高，从不育转换成可育必需要３ｄ以上的日平均气温在３１℃以上的温度诱导。因此，有较长的不育期，又有一定的可育期。     

Elastic property of polyolefin elastomer film cross linked by electron beam irradiation

Polyolefin elastomers were extruded to form films and subjected to electron beam (EB) irradiation at various energy levels. The film samples were characterized to illuminate the effects of EB-induced cross-linking through measurements of gel contents, Fourier transform infra-red (FT-IR) spectroscopy, and variations of tensile properties of the films after the EB irradiations. The EB irradiations introduced crosslinking among the molecular chains resulting increases in initial modulus. The elastic recovery was 83 % at 30 % stain, which is increased by 10 % at 150 kGy compared with pristine. The maximum stain was 1,400 % at 150 kGy which is comparable with commercial polyurethane elastomer.     

Impacts of rising atmospheric carbon dioxide on model terrestrial ecosystems

In model terrestrial ecosystems maintained for three plant generations at elevated concentrations of atmospheric carbon dioxide, increases in photosynthetically fixed carbon were allocated below ground, raising concentrations of dissolved organic carbon in soil. These effects were then transmitted up the decomposer food chain. Soil microbial biomass was unaffected, but the composition of soil fungal species changed, with increases in rates of cellulose decomposition. There were also changes in the abundance and species composition of Collembola, fungal-feeding arthropods. These results have implications for long-term feedback processes in soil ecosystems that are subject to rising global atmospheric carbon dioxide concentrations.