大规模合成具有氧空位的多孔Bi2O3用于有效降解亚甲基蓝

光催化降解有机污染物由于其具有低能耗和绿色环保的特点,已经成为研究的热点.氧化铋纳米晶体的带隙在2.0~2.8 eV之间,利用它催化可见光降解有机污染物具有较高的活性,从而引起了越来越多的关注.尽管近年来已经开发了几种制备Bi2O3基半导体材料的方法,但是仍然难以用简单的方法大规模地制备高活性的Bi2O3催化剂.因此,开发简单可行的大规模制备Bi2O3纳米晶体的方法对于工业废水处理的潜在应用具有重要意义.本文通过蚀刻商用BiSn粉末,然后进行热处理,成功地大规模制备了多孔Bi2O3.获得的多孔Bi2O3在亚甲基蓝(MB)的光催化降解中表现出优异的活性和稳定性.对该机理的进一步研究表明,多孔Bi2O3合适的能带结构允许生成活性氧物种,例如O2^(-·)和·OH,可有效降解MB.

AF-2364，一种杀精子剂候选成分

Inhibition of sperm motility has recently become a promising target for male contraceptive development. AF- 2364, an analogue of Lonidamine （LND）, had a contraceptive effect when orally administered to adult SpragueDawley rats. LND can also target mitochondria to inhibit oxygen consumption and block energy metabolism in tumour cells. However, there are no reports of the effects of AF-2364 on human sperm function. Herein we describe the action of AF-2364 on human sperm in vitro, as well as the mechanisms involved. AF-2364 specifically blocked human sperm motility in vitro. Further experiments revealed that AF-2364 can target sperm mitochondrial permeability transition （MPT） pores to induce the loss of sperm mitochondrial membrane potential （AqUm） and decrease ATP generation; however, no significant changes in the cytoskeletal network or the human sperm proteome were detected after exposure to AF-2364. Incubation of AF-2364 with other human or mouse cell lines indicated that the spermicidal effect at the lower concentration was specific. In summary, the spermicidal effect olAF-2364 involves direct action on sperm MPT pores, and this compound should be further investigated as a new spermicide candidate.

The expression of Usp26 gene in mouse testis and brain

Deubiquitinating enzymes （DUBs） play an important role in ubiquitin-dependent processes as negative regulators of protein ubiquitination. Ubiquitin-specific protease 26 （USP26） is a member of this family. The expression of Usp26 in mammalian testis and in other tissues has yet to be fully elucidated. To study the expression of Usp26 mRNA and protein in various murine tissues, reverse transcription （RT）-PCR and immunohistochemistry analyses were carried out. The RT-PCR analysis showed that the Usp26 transcript was expressed in all of the tested tissues. USP26 protein localization was examined by immunohistochemistry, and it was shown that USP26 was not detectable at 20 days postpartum, with the expression restricted to the cytoplasm of condensing spermatids （steps 9-16）, Leydig cells and nerve fibers in the brain. In addition, the USP26 protein was detected at moderate levels in myocardial ceils, the corpus of epidydimis, epithelium of the renal tubules and the seminal gland of postnatal day 35 mice. Its spatial and temporal expression pattern suggests that Usp26 may play an important role in development or function of the testis and brain. Further research into these possibilities is in progress.

Coherent 420 nm laser beam generated by four-wave mixing in Rb vapor with a single continuous-wave laser

We demonstrate the generation of the coherent 420 nm laser via parametric four-wave mixing process in Rb vapor.A single 778 nm laser with circular polarization is directly injected into a high-density atomic vapor,which drives the atoms from the 5S1/2 state to the 5D5/2 state with monochromatic two-photon transition.The frequency up-conversion laser is generated by the parametric four-wave mixing process under the phase matching condition.This coherent laser is firstly certified by the knife-edge method and a narrow range grating spectrometer.Then the generated laser power is investigated in terms of the power and frequency of the incoming beam as well as the density of the atoms.Finally,a 420 nm coherent laser with power of 19μW and beam quality of Mx^2=1.32,My^2=1.37 is obtained with optimal experimental parameters.This novel laser shows potential prospects in the measurement of material properties,information storage,and underwater optical communication.

Experimental Study on Double Resonance Optical Pumping Spectroscopy in a Ladder-Type System of ^(87)Rb Atoms

Double resonance optical pumping spectroscopy has an outstanding advantage of high signal-to-noise ratio, thus having potential applications in precision measurement. With the counter propagated 780nm and 776nm laser beams acting on a rubidium vapor cell, the high resolution spectrum of 5S1/2 - 5P3/2 - 5D5/2 ladder-type transition of ST Rb atoms is obtained by monitoring the population of the 5S1/2 ground state. The dependence of the spectroscopy lineshape on the probe and coupling fields are comprehensively studied in theory and experiment. This research is helpful for measurement of fundamental physical constants by high resolution spectroscopy.

Effects of entecavir on inflammatory reaction, liver function and liver fibrosis in chronic hepatitis b patients

Objective:To observe the effect of entecavir on inflammatory reaction, liver function and liver fibrosis in patients with chronic hepatitis B.Method:A total of 100 patients with chronic hepatitis B admitted in our hospital from February 2015 to October 2016 were randomly divided into observation group (50 cases) and control group (50 cases). The control group were given reduced glutathione and compound glycyrrhizin and other conventional liver protection;the observation group received entecavir dispersible tablets based on the treatment of the control group. The changes of inflammatory factors, liver function and liver fibrosis indexes of patients in both groups were compared.Results:Before treatment, the difference in inflammatory factors, liver function indexes and liver fibrosis indexes between the two groups was not significant. After treatment, the TGF-β1, hs-CRP and TNF-α levels in both groups were significantly lower than those before treatment, in the observation group, TGF-β1 (144.94±36.21) μg/L, hs-CRP level (48.81±10.74) ng/L and TNF-α level (82.43±22.29) pg/mL were significantly lower than those in the control group, there was significant difference between the two groups. After treatment, ALT, and AST levels in both groups were significantly lower than before treatment, compared with before treatment, TBiL level after treatment was not significant. After treatment, the ALT level (35.71±17.81) U/L and AST level (38.82±14.51) U/L in observation group were significantly lower than those in the control group, while the TBiL level in the observation group were not significantly different from that in the control group. After treatment, the levels of HA (91.71 ± 20.81) μg/mL and IV-C (140.82 ± 48.51) μg/L and LN (73.02 ± 21.06) μg/mL in the observation group were significantly lower than those in the control group.Conclusion:Entecavir combined with conventional drug therapy can effectively improve the inflammatory state of patients with chronic hepatitis B, enhance liver function and reduce liver fibrosis.

Rational design of superior catalysts from topological semimetals with nontrivial energy window

Materials featuring topological energy bands and nontrivial surface states hold significant promise in unlocking unprecedented opportunities for innovating electrocatalytic mechanism.However,it remains a challenge to realize superior topological catalysts which can carry both high catalytic activity and excellent catalytic stability.Here,we propose that a family of Ni-based binary materials hosting fantasying topological conjunct-nodalpoint state and a large nontrivial energy window(NEWD)represents an ideal choice for such superior topological catalysts in hydrogen evolution reaction.The presence of conjunct-nodal-points ensures long Fermi arcs on the surface,thereby enabling an extremely high catalytic activity.The NEWD plays a crucial role in stabilizing the high catalytic activity against external perturbations,such as strain and electron/hole injection.The roles for conjunctnodal-points and NEWD are substantiated by the observable weakening of catalytic performance during topological phase transitions,which result in the removal of the conjunct-nodal-points,NEWD and their corresponding long Fermi arcs.Our work unveils a hidden mechanism and opens a feasible route for developing superior quantum catalysts from novel topology point of view.

Controllable electromagnetically induced grating in a cascade-type atomic system

A controllable electromagnetically induced grating (EIG) is experimentally realized in a coherent rubidium ensemble with 5S1/2-5P3/2-5D5/2 cascade configuration.In our work,a whole picture de-scribing the relation between the first-order diffraction efficiency and the power of the coupling field is experimentally presented for the first time,which agrees well with the theoretical prediction.More important,by fine tuning the experimental parameters,the first-order diffraction efficient of as high as 25% can be achieved and a clear three-order diffraction pattern is also observed.Such a controllable periodic structure can provide a powerful tool for studying the control of light dynamics,pave the way for realizing new optical device.

Moderate Dose of Trolox Preventing the Deleterious Effects of Wi-Fi Radiation on Spermatozoa In vitro through Reduction of Oxidative Stress Damage

Background： The worsening of semen quality, due to the application of Wi-Fi, can be ameliorated by Vitamin E. This study aimed to demonstrate whether a moderate dose of trolox,a new Vitamin E,inhibits oxidative damage on sperms in vitro after exposure to Wi-Fi radiation. Methods： Each of the twenty qualified semen, gathered from June to October 2014 in eugenics clinic, was separated into four aliquots, including sham, Wi-Fi-exposed, Wi-Fi plus 5 mmol/L trolox, and Wi-Fi plus 10 mmol/L trolox groups. At 0 min, all baseline parameters of the 20 samples were measured in sequence. Reactive oxygen species, glutathione, and superoxide dismutase were evaluated in the four aliquots at 45 and 90 min, as were sperm DNA fragments, sperm mitochondrial potential, relative amplification of sperm mitochondrial DNA, sperm vitality, and progressive and immotility sperm. The parameters were analyzed by one-way analysis of variance and Tukey＇s posttest. Results： Among Wi-Fi plus 5 mmol/L trolox, Wi-Fi-exposed and Wi-Fi plus 10 mmol/L trolox groups, reactive oxygen species levels （45 min： 3.80 ± 0.41 RLU·10^-6·ml^-1. 7.50 ± 0.35 RLU·10^-6·ml^-1vs. 6.70 ± 0.47 RLU·10^-6·ml^-1P 〈 0.001; 90 min：5.40 ± 0.21 RLU·10^-6·ml^-1vs. 10.10 ± 0.31 RLU·10^-6·ml^-1. 7.00 ± 0.42 RLU·10^-6·ml^-1P 〈 0.001, respectively）, percentages of tail DNA （45 min： 16.8 ± 2.0% vs. 31.9 ± 2.5% vs. 61.3 ± 1.6%, P 〈 0.001; 90 min： 19.7 ± 1.5% vs. 73.7 ± 1.3% vs. 73.1 ± 1.1%, P 〈 0.001, respectively）, 8-hydroxy-2＇-deoxyguanosine （45 min： 51.89 ± 1.46 pg/ml vs. 104.89 ± 2.19 pg/ml vs. 106.11 ± 1.81 pg/ml , P = 0.012;90 min： 79.96 ± 1.73 pg/ml vs. 141.73 ± 2.90 pg/ml vs. 139.06 ± 2.79 pg/ml; P 〈 0.001）, and percentages of immotility sperm （45 min：27.7 ± 2.7% vs. 41.7 ± 2.2% vs. 41.7 ± 2.5%; 90 min： 29.9 ± 3.3% vs. 58.9 ± 4.0% vs. 63.1 ± 4.0%; all P 〈 0.001） were lowest, and glutathione peroxidase （45 min： 60.50 ± 1.54 U/ml vs. 37.09 ± 1.77 U/ml vs. 28.18 ± 1.06 U/ml; 90 min： 44.61 ± 1.23 U/ml vs. 16.86 ± 0.93 U/ml vs. 29.94 ± 1.56 U/ml; all P 〈 0.001）, percentages of head DNA （45 min： 83.2 ± 2.0% vs. 68.2 ± 2.5% vs. 38.8 ± 1.6%; 90 min： 80.3 ± 1.5% vs. 26.3 ± 1.3% vs. 26.9 ± 1.1%; all P 〈 0.001）, percentages of sperm vitality （45 min： 89.5 ± 1.6% vs. 70.7 ± 3.1% vs. 57.7 ± 2.4%;90 min： 80.8 ± 2.2% vs. 40.4 ± 4.0% vs. 34.7 ± 3.9%; all P 〈 0.001）, and progressive sperm （45 min： 69.3 ± 2.7% vs. 55.8 ± 2.2% vs. 55.4 ± 2.5%; 90 min： 67.2 ± 3.3% vs. 38.2 ± 4.0% vs. 33.9 ± 4.0%; all P 〈 0.001） were highest in Wi-Fi plus 5 mmol/L trolox group at 45 and 90 min, respectively. Other parameters were not affected, while the sham group maintained the baseline. Conclusion：This study found that 5 mmol/L trolox protected the Wi-Fi-exposed semen in vitro from the damage of electromagnetic radiation-induced oxidative stress.

Investigation on the Cs 6S_(1/2)to 7D elec trie quadrupole tr ansition via monochromatic two-photon process at 767 nm

We experimentally demonstrate the cesium electric quadrupole t ransition from the 6S_(1/2)ground st ate to the 7D_(3/2,5/2)excited state t hrough a virtu al level by using a single laser at 767 nm.The excited state energy level population is characterized by varying the laser power,the temperature of the vapor,and the polarization combinations of the laser beams.The optimized experimentai parameters are obtained for a high resolution transition interval identification.The magnetic dipole coupling constant A and elec trie quadrupole coupling constant B for the 7D_(3/2,5/2)states are precisely determined by using the hyperfine levels intervals.The results,A=7.39(0.06)MHz,B=-0.19(0.18)MHz for the 7D_(3/2)state,and A=-1.79(0.05)MHz,B=1.05(0.29)MHz for the 7D_(5/2)state,are in good agreement with the previous reported results.This work is beneficial for the determination of atomic structure information and parity non-conser vat ion,which paves the way for the field of precision measurements and atomic physics.