962 research outputs found
Seebeck Coefficients in Nanoscale Junctions: Effects of Electron-vibration Scattering and Local Heating
We report first-principles calculations of inelastic Seebeck coefficients in
an aluminum monatomic junction. We compare the elastic and inelastic Seebeck
coefficients with and without local heating. In the low temperature regime, the
signature of normal modes in the profiles of the inelastic Seebeck effects is
salient. The inelastic Seebeck effects are enhanced by the normal modes, and
further magnified by local heating. In the high temperature regime, the
inelastic Seebeck effects are weakly suppressed due to the quasi-ballistic
transport.Comment: 3 Figure
Testosterone Depletion by Castration May Protect Mice from Heat-Induced Multiple Organ Damage and Lethality
When the vehicle-treated, sham-operated mice underwent heat stress, the fraction survival and core temperature at +4 h of body heating were found to be 5 of 15 and 34.4°C ± 0.3°C, respectively. Castration 2 weeks before the start of heat stress decreased the plasma levels of testosterone almost to zero, protected the mice from heat-induced death (fraction survival, 13/15) and reduced the hypothermia (core temperature, 37.3°C). The beneficial effects of castration in ameliorating lethality and hypothermia can be significantly reduced by testosterone replacement. Heat-induced apoptosis, as indicated by terminal deoxynucleotidyl- transferase- mediatedαUDP-biotin nick end-labeling staining, were significantly prevented by castration. In addition, heat-induced neuronal damage, as indicated by cell shrinkage and pyknosis of nucleus, to the hypothalamus was also castration-prevented. Again, the beneficial effects of castration in reducing neuronal damage to the hypothalamus as well as apoptosis in multiple organs during heatstroke, were significantly reversed by testosterone replacement. The data indicate that testosterone depletion by castration may protect mice from heatstroke-induced multiple organ damage and lethality
End-to-end thiocyanato-bridged helical chain polymer and dichlorido-bridged copper(II) complexes with a hydrazone ligand: synthesis, characterisation by electron paramagnetic resonance and variable- temperature magnetic studies, and inhibitory effects on human colorectal carcinoma cells
The reactions of the tridentate hydrazone ligand, N’-[1-(pyridin-2-yl)ethylidene]acetohydrazide (HL), obtained by condensation of 2-acetylpyridine with acetic hyadrazide, with copper nitrate trihydrate in the presence of thiocyanate, or with CuCl2 produce two distinct coordination compounds, namely a one-dimensional
helical coordination chain of [CuL(NCS)]n (1) units, and a doubly chlorido-bridged dinuclear complex [Cu2L2Cl2] (2)
(where L=CH3C(O)=N − N=CCH3C5H4N). Single-crystal X-ray structural determination studies reveal that in complex 1, a deprotonated hydrazone ligand L- coordinates a copper(II) ion that is bridged to two neighbouring metal centres by SCN- anions, generating a one-dimensional helical coordination chain. In complex 2, two symmetry-related, adjacent copper(II) coordination entities are doubly chlorido-bridged, producing a dicopper entity with a Cu···Cu distance of 3.402 (1). The two coordination compounds have been fully characterised by elemental analysis, spectroscopic techniques including IR, UV– vis and electron paramagnetic resonance, and variable-temperature magnetic studies. The biological effects of 1 and 2 on the viability of human colorectal carcinoma cells (COLO-205
and HT-29) were evaluated using an MTT assay, and the results indicate that these complexes induce a decrease in cell-population growth of human colorectal carcinoma cells with apoptosis
miRExpress: Analyzing high-throughput sequencing data for profiling microRNA expression
<p>Abstract</p> <p>Background</p> <p>MicroRNAs (miRNAs), small non-coding RNAs of 19 to 25 nt, play important roles in gene regulation in both animals and plants. In the last few years, the oligonucleotide microarray is one high-throughput and robust method for detecting miRNA expression. However, the approach is restricted to detecting the expression of known miRNAs. Second-generation sequencing is an inexpensive and high-throughput sequencing method. This new method is a promising tool with high sensitivity and specificity and can be used to measure the abundance of small-RNA sequences in a sample. Hence, the expression profiling of miRNAs can involve use of sequencing rather than an oligonucleotide array. Additionally, this method can be adopted to discover novel miRNAs.</p> <p>Results</p> <p>This work presents a systematic approach, miRExpress, for extracting miRNA expression profiles from sequencing reads obtained by second-generation sequencing technology. A stand-alone software package is implemented for generating miRNA expression profiles from high-throughput sequencing of RNA without the need for sequenced genomes. The software is also a database-supported, efficient and flexible tool for investigating miRNA regulation. Moreover, we demonstrate the utility of miRExpress in extracting miRNA expression profiles from two Illumina data sets constructed for the human and a plant species.</p> <p>Conclusion</p> <p>We develop miRExpress, which is a database-supported, efficient and flexible tool for detecting miRNA expression profile. The analysis of two Illumina data sets constructed from human and plant demonstrate the effectiveness of miRExpress to obtain miRNA expression profiles and show the usability in finding novel miRNAs.</p
Purple urine bag syndrome in nursing homes: Ten elderly case reports and a literature review
Purple urine bag syndrome (PUBS) is a rare occurrence, in which the patient has a purple-colored urine bag following urinary catheterization for hours to days. Most of authors believe it is a mixture of indigo (blue) and indirubin (red) that becomes purple. Previous study showed that PUBS occurred predominantly in chronically catheterized, constipated women. We collected 10 elderly patients with PUBS in two nursing homes. The first two cases were identified by chart review in 1987 and 2003, and then later eight cases (42.1%) were collected among 19 urinary catheterized elderly in the period between January 2007 and June 2007. In the present report, PUBS probably can occur in any patients with the right elements, namely urinary tract infection (UTI) with bacteria possessing these enzymes, diet with enough tryptophan, and being catheterized. Associations with bed-bound state, Alzheimer’s, or dementia from other causes are reflections of the state of such patients who are at higher risk for UTI, and hence PUBS occurred. Although we presented PUBS as a harmless problem, prevention and control of the nosocomial catheter-associated UTIs (CAUTIs) has become very important in the new patient-centered medical era. Thus, we should decrease the duration of catheterization, improve catheter care, and deploy technological advances designed for prevention, especially in the elderly cared for in nursing homes
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