Measurement of the velocities in the transient acceleration process using all-fiber photonic Doppler velocimetry

Based on analysis of basic photonic Doppler velocimetry (PDV), a formula to measure velocity variation in a single cycle is put forward. PDV has been improved in three aspects, namely, the laser, the detector and the data processing. A measurement system for velocity of the initial stage of a shock motion has been demonstrated. Instantaneous velocity measurements have been performed. The experimental results have a good agreement with the values obtained from the accelerometer. Compared with the traditional fringe method, the proposed method in this paper can identify instantaneous velocity variation. So it is particularly suitable for measuring the velocity in the transient acceleration process of shock waves and detonation waves

Magnetic field effects on the electroluminescence of organic light emitting devices: A tool to indicate the carrier mobility

The magnetoelectroluminescence (MEL) of organic light emitting devices with a N, N′ -bis(l-naphthyl)- N, N′ -diphenyl- 1, l′ -biphentl- 4, 4′ -diamine:tris-(8-hydroxyquinoline) aluminum (NPB: Alq 3) mixed emission layer (EML) has been investigated. We find that MEL is maximized when the volume ratio of NPB of the mixed EML reaches 30% and the EML thickness is 40 nm. The features of MEL under various magnetic field strengths are insensitive to the change in EML thickness and mixing ratio. Meanwhile, MEL has a close relationship with the carrier mobility. We have conducted a theoretical study to further verify the relationship. Our experimental and theoretical results confirm that MEL can function as a tool to indicate the mobility. © 2010 American Institute of Physics.published_or_final_versio

Synthesis, structure, and magnetism in the ferromagnet La_{3}MnAs_{5}: Well-separated spin chains coupled via itinerant electrons

In this work, we systematically report the synthesis, structure, and magnetism of a compound of filled anti-Mn3Si5 type La3MnAs5. It crystallizes in a hexagonal structure with the space group of P63/mcm (193). The structure consists of face-sharing MnAs6 octahedral chains along the c axis, which are well separated by a large distance of 8.9913 Å, demonstrating a strong one-dimensional (1D) structural character. Physical property measurements indicate that La3MnAs5 is a ferromagnetic metal with TC ∼ 112 K. Due to the short-range intrachain spin coupling, the susceptibility deviates from the Curie-Weiss behavior in a wide temperature window and the magnetic entropy corresponding to the ferromagnetic transition is significantly lower than that expected from the fully saturated state. The magnetic critical behavior studies show that La3MnAs5 can be described by the three-dimensional Heisenberg model. The orbital hybridization between the 1D MnAs6 chain and intermediate La atom near the Fermi level reveals that the itinerant electrons play a key role in transmitting spin interaction among the MnAs6 spin chains. Our results indicate that La3MnAs5 is a rare ferromagnetic metal with well-separated spin chains, which provides a good opportunity to study the mechanism of interchain spin coupling via itinerant electrons

The specificity and patterns of staining in human cells and tissues of p16INK4a antibodies demonstrate variant antigen binding

The validity of the identification and classification of human cancer using antibodies to detect biomarker proteins depends upon antibody specificity. Antibodies that bind to the tumour-suppressor protein p16INK4a are widely used for cancer diagnosis and research. In this study we examined the specificity of four commercially available anti-p16INK4a antibodies in four immunological applications. The antibodies H-156 and JC8 detected the same 16 kDa protein in western blot and immunoprecipitation tests, whereas the antibody F-12 did not detect any protein in western blot analysis or capture a protein that could be recognised by the H-156 antibody. In immunocytochemistry tests, the antibodies JC8 and H-156 detected a predominately cytoplasmic localised antigen, whose signal was depleted in p16INK4a siRNA experiments. F-12, in contrast, detected a predominately nuclear located antigen and there was no noticeable reduction in this signal after siRNA knockdown. Furthermore in immunohistochemistry tests, F-12 generated a different pattern of staining compared to the JC8 and E6H4 antibodies. These results demonstrate that three out of four commercially available p16INK4a antibodies are specific to, and indicate a mainly cytoplasmic localisation for, the p16INK4a protein. The F-12 antibody, which has been widely used in previous studies, gave different results to the other antibodies and did not demonstrate specificity to human p16INK4a. This work emphasizes the importance of the validation of commercial antibodies, aside to the previously reported use, for the full verification of immunoreaction specificity

Approaching the ideal elastic limit of metallic glasses

The ideal elastic limit is the upper bound to the stress and elastic strain a material can withstand. This intrinsic property has been widely studied for crystalline metals, both theoretically and experimentally. For metallic glasses, however, the ideal elastic limit remains poorly characterized and understood. Here we show that the elastic strain limit and the corresponding strength of submicron-sized metallic glass specimens are about twice as high as the already impressive elastic limit observed in bulk metallic glass samples, in line with model predictions of the ideal elastic limit of metallic glasses. We achieve this by employing an in situ transmission electron microscope tensile deformation technique. Furthermore, we propose an alternative mechanism for the apparent 'work hardening' behaviour observed in the tensile stress–strain curves

Observation of CR Anisotropy with ARGO-YBJ

The measurement of the anisotropies of cosmic ray arrival direction provides important informations on the propagation mechanisms and on the identification of their sources. In this paper we report the observation of anisotropy regions at different angular scales. In particular, the observation of a possible anisotropy on scales between $\sim$ 10 $^{\circ}$ and $\sim$ 30 $^{\circ}$ suggests the presence of unknown features of the magnetic fields the charged cosmic rays propagate through, as well as potential contributions of nearby sources to the total flux of cosmic rays. Evidence of new weaker few-degree excesses throughout the sky region $195^{\circ}\leq$ R.A. $\leq 315^{\circ}$ is reported for the first time.Comment: Talk given at 12th TAUP Conference 2011, 5-9 September 2011, Munich, German

Tumor Necrosis Factor-Alpha G308α Gene Polymorphism and Essential Hypertension: A Meta-Analysis Involving 2244 Participants

BACKGROUND: The tumor necrosis factor-alpha (TNFα) G308A gene polymorphism has been implicated in susceptibility to essential hypertension (EH), but study results are still controversial. OBJECTIVE AND METHODS: The present meta-analysis is performed to investigate the relationship between the TNFα G308A gene polymorphism and EH. Electronic databases were searched and seven separate studies on the association of the TNF α G308A gene polymorphism with EH were analyzed. The meta-analysis involved 1092 EH patients and 1152 controls. The pooled odds ratios (ORs) and their corresponding 95% confidence interval (CI) were calculated by a fixed or random effect model. RESULTS: A significant relationship between the TNFα G308A gene polymorphism and EH was found in an allelic genetic model (OR: 1.45, 95% CI: 1.17 to 1.80, P = 0.0008), a recessive genetic model (OR: 3.181, 95% CI: 1.204 to 8.408, P = 0.02), and a homozygote model (OR: 3.454, 95% CI: 1.286 to 9.278, P = 0.014). No significant association between them was detected in both a dominant genetic model (OR: 1.55, 95% CI: 0.99 to 2.42, P = 0.06) or a heterozygote genetic model (OR: 1.45, 95% CI: 0.90 to 2.33, P = 0.13). CONCLUSION: The TNFα G308A gene polymorphism is associated with EH susceptibility

Indium Tin Oxide@Carbon Core–Shell Nanowire and Jagged Indium Tin Oxide Nanowire

This paper reports two new indium tin oxide (ITO)-based nanostructures, namely ITO@carbon core–shell nanowire and jagged ITO nanowire. The ITO@carbon core–shell nanowires (~50 nm in diameter, 1–5 μm in length,) were prepared by a chemical vapor deposition process from commercial ITO nanoparticles. A carbon overlayer (~5–10 in thickness) was observed around ITO nanowire core, which was in situ formed by the catalytic decomposition of acetylene gas. This carbon overlayer could be easily removed after calcination in air at an elevated temperature of 700°C, thus forming jagged ITO nanowires (~40–45 nm in diameter). The growth mechanisms of ITO@carbon core–shell nanowire and jagged ITO nanowire were also suggested

A Meta-Analysis of Caspase 9 Polymorphisms in Promoter and Exon Sequence on Cancer Susceptibility

BACKGROUND: Caspases are important regulators and executioners in apoptosis pathway and have been defined as either tumor suppressors or oncogenes. Polymorphisms in promoter and exon of caspase 9 were shown to confer genetic susceptibility to multiple cancers, but the results were inconsistent. To accomplish a more precise estimation of the relationship, a meta-analysis was performed. METHODOLOGY/PRINCIPAL FINDINGS: We assessed published studies of the association between caspase 9 polymorphisms and cancer risk from nine studies with 5,528 subjects for rs4645978, six studies with 2,403 subjects for rs105276 and two studies for rs4645981. Overall meta-analysis indicated that no evidence of an association between rs4645978 and cancers was found. Through the stratified analysis, statistically significant reduced cancer risks were observed among Caucasians (AG vs AA: OR = 0.81, 95% CI = 0.66-0.99, P(heterogeneity) = 0.150 and the dominant model: OR = 0.86, 95% CI = 0.75-0.99, P(heterogeneity) = 0.290) and prostate cancer. As for rs105276, Ex5+32G>A polymorphism was found with protective effect in overall meta-analysis (AA vs GG: OR = 0.75, 95% CI = 0.60-0.92, P(heterogeneity) = 0.887; A vs G: OR = 0.85, 95% CI = 0.77-0.95, P(heterogeneity) = 0.739 and the recessive model: OR = 0.68, 95% CI = 0.56-0.82, P(heterogeneity) = 0.309) and Asians group. While for rs4645981, a statistically significant increase in risk of lung cancer was shown in Asians (T vs C: OR = 1.23, 95% CI = 1.07-1.42, P(heterogeneity) = 0.399 and the dominant model: OR = 1.22, 95% CI = 1.04-1.43, P(heterogeneity) = 0.660). CONCLUSIONS/SIGNIFICANCE: Our meta-analysis suggests that the caspase 9 rs4645978 most likely contributes to decreased susceptibility to cancer in Caucasians and prostate cancer. The A allele of rs105276 might be a protective factor for cancer, especially for Asians. However, it seems that rs4645981 confers increased susceptibility to lung cancer in Asians