5-Channel Polymer/Silica Hybrid Arrayed Waveguide Grating.

A 5-channel polymer/silica hybrid arrayed waveguide grating (AWG), fabricated through a simple and low-cost microfabrication process is proposed, which covers the entire O-band (1260-1360 nm) of the optical communication wavelength system. According to the simulation results, the insertion loss is lower than 4.7 dB and the crosstalk within 3-dB bandwidth is lower than ~-28 dB. The actual fiber-fiber insertion loss is lower than 14.0 dB, and the crosstalk of the 5 channels is less than -13.0 dB. The demonstrated AWG is ideally suitable for optical communications, but also has potential in the multi-channel sensors.

Photoperiodism dynamics during the domestication and improvement of soybean.

Soybean (Glycine max) is a facultative short-day plant with a sensitive photoperiod perception and reaction system, which allows it to adjust its physiological state and gene regulatory networks to seasonal and diurnal changes in environmental conditions. In the past few decades, soybean cultivation has spread from East Asia to areas throughout the world. Biologists and breeders must now confront the challenge of understanding the molecular mechanism of soybean photoperiodism and improving agronomic traits to enable this important crop to adapt to geographical and environmental changes. In this review, we summarize the genetic regulatory network underlying photoperiodic responses in soybean. Genomic and genetic studies have revealed that the circadian clock, in conjunction with the light perception pathways, regulates photoperiodic flowering. Here, we provide an annotated list of 844 candidate flowering genes in soybean, with their putative biological functions. Many photoperiod-related genes have been intensively selected during domestication and crop improvement. Finally, we describe recent progress in engineering photoperiod-responsive genes for improving agronomic traits to enhance geographic adaptation in soybean, as well as future prospects for research on soybean photoperiodic responses.

Investigation of interaction of antibacterial drug sulfamethoxazole with human serum albumin by molecular modeling and multi-spectroscopic method.

Interaction of sulfamethoxazole (SMX) with human serum albumin (HSA) was investigated by molecular modeling and multi-spectroscopic methods under physiological conditions. The interaction mechanism was firstly predicted through molecular modeling that confirmed the interaction between SMX and HSA. The binding parameters and the thermodynamic parameters at different temperatures for the reaction had been calculated according to the Stern-Volmer, Hill, Scatchard and the Van't Hoff equations, respectively. One independent class of binding site existed during the interaction between HSA and SMX. The binding constants decreased with the increasing temperatures, which meant that the quenching mechanism was a static quenching. The thermodynamic parameters of the reaction, namely standard enthalpy ΔH(0) and entropy ΔS(0), had been calculated to be -16.40 kJ mol(-1) and 32.33 J mol(-1) K(-1), respectively, which suggested that the binding process was exothermic, enthalpy driven and spontaneous. SMX bound to HSA was mainly based on electrostatic interaction, but hydrophobic interactions and hydrogen bonds could not be excluded from the binding. The conformational changes of HSA in the presence of SMX were confirmed by the three-dimensional fluorescence spectroscopy, UV-vis absorption spectroscopy and circular dichroism (CD) spectroscopy. CD data suggested that the protein conformation was altered with the reduction of α-helices from 55.37% to 41.97% at molar ratio of SMX/HSA of 4:1.

[A Raman study of ZnO powders with ZnO2 as precursor].

Raman spectra of ZnO powders prepared by firing ZnO2 precipitate were reported in detail for the first time. By comparing the spectra with that of the sample fabricated by another method and analyzing frequency difference between the focused-laser irradiated samples with different firing temperature in preparation, it was concluded that the -333 cm(-1) peak is ascribed to E2 (high)-E2 (low) and the -661 cm(-1) peak to its overtone. In addition, a new interpretation for the observed Raman peaks between 400 and 500 cm(-1) in ZnO2 powders was presented based on the IR data and ab initio calculation.