Temperature dependent distinct coupling and dispersions of heavy- and light-hole excitonic polaritons in ZnO

Distinct coupling behavior of heavy- and light-hole excitonic polaritons in ZnO was unveiled by investigating the optical reflectance spectra of a high quality ZnO single crystal as a function of temperature both experimentally and theoretically. A resonance like coupling region was found at a temperature of around 50 K at which several relevant physical quantities such as the transverse exciton transition energy, polarizability, and damping parameters of the two kinds of excitonic polaritons were revealed to overturn. Calculated dispersions correctly reflect the nature of coupled photon and exciton and reproduce the spectral structures of the interacting polaritons. © 2012 American Institute of Physics.published_or_final_versio

Nature of red luminescence band in research-grade ZnO single crystals: A “self-activated” configurational transition

published_or_final_versio

人乳头瘤病毒衣壳蛋白C末端结构臂具有免疫原性并参与病毒—宿主细胞的相互作用

文章简介宫颈癌是全球女性第二大常见恶性肿瘤,人乳头瘤病毒(HPV)是导致女性宫颈癌发生的主要原因。HPV型别众多,主要的高危型型别种类多达15种,且型别间免疫血清交叉保护能力极低,目前国际上已上市的预防性多价HPV疫苗均不能为接种者提供完全保护。长期以来,高分辨率HPV的病毒结构信息的缺乏限制了对HPV病毒的组装模式和感染机制的深入理解,进国家自然科学基金；美国国立卫生院(NIH)基金的资助

China’s Weibo: is faster different?

The popularization of microblogging in China represents a new challenge to the state’s regime of information control. The speed with which information is diffused in the microblogosphere has helped netizens to publicize and express their discontent with the negative consequences of economic growth, income inequalities and official corruption. In some cases, netizen led initiatives have facilitated the mobilization of online public opinion and forced the central government to intervene to redress acts of lower level malfeasance. However, despite the growing corpus of such cases, the government has quickly adapted to the changing internet ecology and is using the same tools to help it maintain control of society by enhancing its claims to legitimacy, circumscribing dissent, identifying malfeasance in its agents and using online public opinion to adapt policy and direct propaganda efforts. This essay reflects on microblogging in the context of the Chinese internet, and argues that successes in breaking scandals and mobilizing opinion against recalcitrant officials should not mask the reality that the government is utilizing the microblogosphere to its own advantage

Ion-implantation induced nano distortion layer and its influence on nonlinear optical properties of ZnO single crystals

Author name used in this publication: G. Y. Gao2011-2012 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Recent changes of water discharge and sediment load in the Yellow River basin, China

The Yellow River basin contributes approximately 6% of the sediment load from all river systems globally, and the annual runoff directly supports 12% of the Chinese population. As a result, describing and understanding recent variations of water discharge and sediment load under global change scenarios are of considerable importance. The present study considers the annual hydrologic series of the water discharge and sediment load of the Yellow River basin obtained from 15 gauging stations (10 mainstream, 5 tributaries). The Mann-Kendall test method was adopted to detect both gradual and abrupt change of hydrological series since the 1950s. With the exception of the area draining to the Upper Tangnaihai station, results indicate that both water discharge and sediment load have decreased significantly (p<0.05). The declining trend is greater with distance downstream, and drainage area has a significant positive effect on the rate of decline. It is suggested that the abrupt change of the water discharge from the late 1980s to the early 1990s arose from human extraction, and that the abrupt change in sediment load was linked to disturbance from reservoir construction.Geography, PhysicalGeosciences, MultidisciplinarySCI(E)43ARTICLE4541-5613

Dietary intake of plant- and animal-derived protein and incident cardiovascular diseases:the pan-European EPIC-CVD case–cohort study

Background: Epidemiological evidence suggests that a potential association between dietary protein intake and cardiovascular disease (CVD) may depend on the protein source, that is, plant- or animal-derived, but past research was limited and inconclusive. Objectives: To evaluate the association of dietary plant- or animal-derived protein consumption with risk of CVD, and its components ischemic heart disease (IHD) and stroke. Methods: This analysis in the European Prospective Investigation into Cancer and Nutrition (EPIC)-CVD case–cohort study included 16,244 incident CVD cases (10,784 IHD and 6423 stroke cases) and 15,141 subcohort members from 7 European countries. We investigated the association of estimated dietary protein intake with CVD, IHD, and stroke (total, fatal, and nonfatal) using multivariable-adjusted Prentice-weighted Cox regression. We estimated isocaloric substitutions of replacing fats and carbohydrates with plant- or animal-derived protein and replacing food-specific animal protein with plant protein. Multiplicative interactions between dietary protein and prespecified variables were tested. Results: Neither plant- nor animal-derived protein intake was associated with incident CVD, IHD, or stroke in adjusted analyses without or with macronutrient-specified substitution analyses. Higher plant-derived protein intake was associated with 22% lower total stroke incidence among never smokers [HR 0.78, 95% confidence intervals (CI): 0.62, 0.99], but not among current smokers (HR 1.08, 95% CI: 0.83, 1.40, P-interaction = 0.004). Moreover, higher plant-derived protein (per 3% total energy) when replacing red meat protein (HR 0.52, 95% CI: 0.31, 0.88), processed meat protein (HR 0.39, 95% CI: 0.17, 0.90), and dairy protein (HR 0.54, 95% CI: 0.30, 0.98) was associated with lower incidence of fatal stroke.Conclusion: Plant- or animal-derived protein intake was not associated with overall CVD. However, the association of plant-derived protein consumption with lower total stroke incidence among nonsmokers, and with lower incidence of fatal stroke highlights the importance of investigating CVD subtypes and potential interactions. These observations warrant further investigation in diverse populations with varying macronutrient intakes and dietary patterns.</p

Structural recombination of polymethylsilicone induced by laser plasma

A special synthetic reaction has been developed, in which vapor of the reactant interacts with the high temperature plasma generated by laser ablating a graphite target. By selecting chained methylsilicone as reactant, a series of methylsilsesquioxanes products with various structural configurations have been obtained. Among them, two products, which were separated by sublimation in high vacuum and recrystalization, were characterized by X - ray crystal diffraction as (CH3SiO1.5)(n)(n = 8, 10). Both of them are found to have three - dimensional cage structure. In addition, other products with double ring structure were detected by GC - MS analysis. The results demonstrate the potential application of the synthetic reaction. In the reaction described in this article, resulting from the collision and energy - transfer of the laser plasma, chain structure of the reactant dissociated and recombined to give the cage and ring structure of the products

Fabrication of Porous TiO2 Hollow Spheres and Their Application in Gas Sensing

In this work, porous TiO2 hollow spheres with an average diameter of 100 nm and shell thickness of 20 nm were synthesized by a facile hydrothermal method with NH4HCO3 as the structure-directing agent, and the formation mechanism for this porous hollow structure was proved to be the Ostwald ripening process by tracking the morphology of the products at different reaction stages. The product was characterized by SEM, TEM, XRD and BET analyses, and the results show that the as-synthesized products are anatase phase with a high surface area up to 132.5 m2/g. Gas-sensing investigation reveals that the product possesses sensitive response to methanal gas at 200°C due to its high surface area

Exploring the Caffeine-Induced Teratogenicity on Neurodevelopment Using Early Chick Embryo

Caffeine consumption is worldwide. It has been part of our diet for many centuries; indwelled in our foods, drinks, and medicines. It is often perceived as a “legal drug”, and though it is known to have detrimental effects on our health, more specifically, disrupt the normal fetal development following excessive maternal intake, much ambiguity still surrounds the precise mechanisms and consequences of caffeine-induced toxicity. Here, we employed early chick embryos as a developmental model to assess the effects of caffeine on the development of the fetal nervous system. We found that administration of caffeine led to defective neural tube closures and expression of several abnormal morphological phenotypes, which included thickening of the cephalic mesenchymal tissues and scattering of somites. Immunocytochemistry of caffeine-treated embryos using neural crest cell markers also demonstrated uncharacteristic features; HNK1 labeled migratory crest cells exhibited an incontinuous dorsal-ventral migration trajectory, though Pax7 positive cells of the caffeine-treated groups were comparatively similar to the control. Furthermore, the number of neurons expressing neurofilament and the degree of neuronal branching were both significantly reduced following caffeine administration. The extent of these effects was dose-dependent. In conclusion, caffeine exposure can result in malformations of the neural tube and induce other teratogenic effects on neurodevelopment, although the exact mechanism of these effects requires further investigation