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On aerodynamic noises radiated by the pantograph system of high-speed trains

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Acta Mechanica Sinica 2013年第3期29卷 399-410页

作者： Hua-Hua Yu Jia-Chun Li hui-qin zhang LMFS Institute of Mechanics Chinese Academy of Sciences

Pantograph system of high-speed trains become significant source of aerodynamic noise when travelling speed exceeds 300 km/h. In this paper, a hybrid method of non-linear acoustic solver （NLAS） and Ffowcs Williams-Hawkings （FW-H） acoustic analogy is used to predict the aerodynamic noise of pantograph system in this speed range. When the simulation method is validated by a benchmark problem of flows around a cylinder of finite span, we calculate the near flow field and far acoustic field surrounding the pantograph system. And then, the frequency spectra and acoustic attenuation with distance are analyzed, showing that the pantograph system noise is a typical broadband one with most acoustic power restricted in the medium-high frequency range from 200 Hz to 5 kHz. The aerodynamic noise of pantograph systems radiates outwards in the form of spherical waves in the far field. Analysis of the overall sound pressure level （OASPL） at different speeds exhibits that the acoustic power grows approximately as the 4th power of train speed. The comparison of noise reduction effects for four types of pantograph covers demonstrates that only case 1 can lessen the total noise by about 3 dB as baffles on both sides can shield sound wave in the spanwise direction. The covers produce additional aerodynamic noise themselves in the other three cases and lead to the rise of OASPLs.

关键词： Aerodynamic noise · NLAS · FW–H acoustic analogy · Pantograph system · High-speed train

Sperm chromatin structure assay results after swim-up are related only to embryo quality but not to fertilization and pregnancy rates following IVF

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Asian Journal of Andrology 2011年第6期13卷 862-866页

作者： Zhi-Hong Niu hui-Juan Shi hui-qin zhang Ai-Jun zhang Yi-Juan Sun Yun Feng IVF Unit Department of Obstetrics and Gynecology Ruijin Hospital Affiliated to Shanghai Jiao Tong University Shanghai 200025 China Shanghai Institute of Planned Parenthood Research Shanghai 200032 China

The aim of this study was to investigate whether the sperm chromatin structure assay （SCSA） results after swim-up are related to fertilization rates, embryo quality and pregnancy rates following in vitrofertilization （IVF）. A total of 223 couples undergoing IVF in our hospital from October 2008 to September 2009 were included in this study. Data on the IVF process and sperm chromatin structure assay results were collected. Fertilization rate, embryo quality and IVF success rates of different DNA fragmentation index （DFI） subgroups and high DNA stainability （HDS） subgroups were compared. There were no significant differences in fertilization rate, clinical pregnancy or delivery rates between the DFI and HDS subgroups. However, the group with abnormal DFI had a lower good embryo rate. So, we concluded that the SCSA variables, either DFI or HDS after swim-up preparation, were not valuable in predicting fertilization failure or pregnancy rate, but an abnormal DFI meant a lower good embryo rate following IVF.

关键词： embryo fertilization in-vitro fertilization sperm chromatin structure assay

Molecular and functional characterization of a candidate sex pheromone receptor OR1 in Spodoptera fitura

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Insect Science 2017年第4期24卷 543-558页

作者： qin-hui zhang Zhong-Nan Wu Jing-Jiang Zhou Yong-Jun Du College of Life Sciences Sichuan University Chengdu 610065 China Institute of Health & Environmental Ecology Wenzhou Medical University Wenzhou Zhejiang 325035 China Department of Biological Chemistry and Crop Protection Rothamsted Research BBSRC Harpenden Herts. AL5 2JQ UK

Olfaction is primarily mediated by highly specified olfactory receptors （ORs）. Here, we cloned and identified an olfactory receptor, named SlituOR1 （Genbank no. JN835269）, from Spodoptera litura and found evidence that it is a candidate pheromone receptor. It exhibited male-biased expression in the antennae, where it was localized at the base of sensilla trichoidea, the antennal sensilla mainly responsive to pheromones in moths. Conserved orthologues of this receptor, found among known pheromone receptors within the Lepidoptera, and SlituOR1 were placed among a clade of candidate pheromone re- ceptors in a phylogeny tree of insect OR gene sequences. SlituOR1 showed differential expression in S. litura populations attracted to traps baited with different ratios of the two sex pheromone components （9Z,11E）-tetradecadienyl acetate （Z9E11-14：OAc） and （9Z,12E）-tetradecadienyl acetate （Z9E12-14：OAc）. Knocking down of SlituOR1 by RNA interference reduced the electroantennogram （EAG） response to Z9E11-14：OAc, and this result is consistent with the field trapping experiment. We infer that variation in transcrip- tion levels of olfactory receptors may modulate sex pheromone perception in male moths and could provide some of the flexibility required to maintain the functionality of com- munication with females when a population is adapting to a new niche and reproductive isolation becomes an advantage.

关键词： electroantennogram (EAG) individual variation in situ hybridization ol-factory receptor (9Z, 11E)-tetradecadienyl acetate (9Z, 12E)-tetradecadienyl acetate RNAinterference

Post-tunable salt gel electrolytes toward flexible supercapacitor switches

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Journal of Energy Chemistry 2025年第1期100卷 114-124页

作者： hui Wang Shuang Chen Xuming Liu qin zhang Xin Liu Polymeric and Soft Materials Laboratory School of Chemistry and Life Science and Advanced Institute of Materials Science Changchun University of Technology Polymeric and Soft Materials Laboratory School of Chemical Engineering and Advanced Institute of Materials Science Changchun University of Technology

Convertible hydrogel supercapacitors have emerged as promising energy storage devices in switches,diodes, and transistors. However, inherent weaknesses in ionic conductivity, mechanical properties,and water retention of hydrogel electrolytes seriously hinder their development. Inspired by the hardness conversion of sea cucumber skin, a conductivity and mechanics dual-tunable salt gel electrolyte is successfully designed. The salt gel presents a reversible switching of conductors-insulators and a mechanical regulation between softness and hardness via the dissolution-crystallization transition of sodium acetate trihydrate（SAT）. Meanwhile, the salt gels spontaneously grow a layer of “armor” through saturated phase-change salt crystals effectively reducing water evaporation of hydrogel ***, this phase-change soft-rigid conversion strategy will expand the capabilities of gel-based flexible supercapacitors(area capacitance: 258.6 mF cm-2), and the capacitance retention rate could still reach 86.9% after 3000 cycles at high temperatures. Moreover, the salt gel supercapacitor is potentially used in over-heat alarm systems. It is anticipated that the strategy of conductivity and mechanics of dual-tunable salt gel would provide a new perspective on the development of energy storage devices,wearable electronics, and flexible robots.

关键词： Capacitance

Effects of Total Alkaloids in Buxus microphylla Leaves on Aorta Smooth Muscle of Rats and Their Mechanisms

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Chinese Herbal Medicines 2012年第2期4卷 136-141页

作者： hui-qin zhang[a] Yan-yan LIU[b] Yong-wen LI[a] Li LI[a] Zhi-qing CUI[c] Department of Pharmacology Guilin Medical College Guilin 541001 China

Objective To investigate the effects of total alkaloids in Buxus microphylla leaves(ABML)on isolated rats thoracic aorta rings,and then to explore the possible mechanisms underlying the *** Thoracic aortas of Wistar rats were isolated,removed,and mounted onto an organ *** effects of ABML at different concentration on the contraction of isolated thoracic aorta rings(with and without endothelium)precontracted with KCl or PE were observed with organ bath ***-effect curves of CaCl2 were recorded by organ bath *** concentration of intracellular Ca 2+ ([Ca 2+ ]i)increased by PE,KCI,and caffeine in the presence of ABML was determined using Ca 2+ sensitive fluorescence indicator Fura-2/AM loaded thoracic aorta vascular smooth muscle (VSM)cells of *** In aorta rings precontracted with PE and KCl,ABML produced concentration- dependent relaxation in both intact and denuded endothelium ring *** was no difference in the inhibition of contraction between the intact and denuded endothelium ring groups at the same *** of isolated thoracic aorta rings to ABML led to a significant reduction in the contracting response induced by CaCl2,and shifted the cumulative concentration-response curves to *** could significantly inhibit the extracellular Ca 2+ influx induced by PE and KCl under[Ca 2+ ]0 of 1.5 mmol/L,with inhibitory ratios of 40.2%and 49.9%,*** the case of Ca 2+ -free,ABML could significantly inhibit the intracellular Ca 2+ release induced by PE,with inhibitory ratio of 72.4%.Conclusion ABML relaxes thoracic aorta VSM cells by suppressing influx of extracellular Ca 2+ via voltage-dependent Ca 2+ channel and receptor-operated Ca 2+ channel.

关键词： Ca 2+ Fura-2/AM isolated thoracic aorta rings total alkaloids of Buxus microphylla leaves vascular smooth muscle cells

GPS: graph contrastive learning via multi-scale augmented views from adversarial pooling

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Science China(Information Sciences) 2025年第1期68卷 145-158页

作者： Wei JU Yiyang GU Zhengyang MAO Ziyue QIAO Yifang qin Xiao LUO hui XIONG Ming zhang School of Computer Science National Key Laboratory for Multimedia Information ProcessingPeking University Artificial Intelligence Thrust The Hong Kong University of Science and Technology Department of Computer Science University of California

Self-supervised graph representation learning has recently shown considerable promise in a range of fields, including bioinformatics and social networks. A large number of graph contrastive learning approaches have shown promising performance for representation learning on graphs, which train models by maximizing agreement between original graphs and their augmented views(i.e., positive views). Unfortunately, these methods usually involve pre-defined augmentation strategies based on the knowledge of human experts. Moreover, these strategies may fail to generate challenging positive views to provide sufficient supervision signals. In this paper, we present a novel approach named graph pooling contrast(GPS) to address these *** by the fact that graph pooling can adaptively coarsen the graph with the removal of redundancy, we rethink graph pooling and leverage it to automatically generate multi-scale positive views with varying emphasis on providing challenging positives and preserving semantics, i.e., strongly-augmented view and weakly-augmented view. Then, we incorporate both views into a joint contrastive learning framework with similarity learning and consistency learning, where our pooling module is adversarially trained with respect to the encoder for adversarial robustness. Experiments on twelve datasets on both graph classification and transfer learning tasks verify the superiority of the proposed method over its counterparts.

关键词： graph representation learning graph neural networks graph contrastive learning graph augmentations graph pooling

Assessment of Uterine Receptivity by Endometrial and Subendometrial Blood Flows Measured by Vaginal Color Doppler Ultrasound in Women Undergoing IVF Treatment

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Journal of Reproduction and Contraception 2007年第3期18卷 205-212页

作者： Min-zhi GAO Xiao-ming ZHAO Wen-ying LI Gui-mei LIU Xiao-feng JIA hui-qin zhang Reproductive Medicine Center of Renji Hospital Medical College of Jiao Tong University Shanghai 200001 China Shanghai Institution of Planned Parenthood Research Shanghai 200032 China

Objective To evaluate endometrial and subendometrial blood flows measured by vaginal color Doppler ultrasound as a predicator of endometrial receptivity in women undergoing IVF treatment. Methods A total of 119 infertile patients undergoing the first IVF/ICSI-ET cycle were recruited. Three groups were divided according to a color Doppler ultrasound examination performed on the day of hCG injection. Group A, endometrial and subendometrial blood flows were 2 branches and below; group B, endometrial and subendometrial blood flows were between 3 and 4 branches; group C, endometrial and subendometrial blood flows were 5 branches and above. Patients were transferred 1-3 embryos each. Demographic data, ovarian responses, endometrial thickness, PI, RI, development of embryo and IVF result among groups were compared. Results Demographic data, ovarian responses, endometrial thickness, PI, RI and development of embryo among groups have no significant difference. The pregnancy rate of group A was significantly lower than that of group B （P〈0.05） and group C （P〈0.01）. The implantation rate of group A was significantly lower than than of group C （P〈0.01）. There was no significant difference of the rate of pregnancy and implantation between group B and group C （P〉0.05）. Conclusion Endometrial and subendometrial blood flows measured by vaginal color Doppler ultrasound is a good predicator of pregnancy during IVF treatment. A good endometrial and subendometrial blood flows is benefit for the result of IVF.

关键词： endometrial and subendometrial blood flows endometrial receptivity in vitro fertilization-embryo transfer (IVF) color Doppler ultrasound

Revised Super-long Down-regulation Protocol Improves the Outcome of Infertile Patients with Repeated Implantation Failure in IVF/ICSI-ET

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Journal of Reproduction and Contraception 2014年第2期25卷 89-96页

作者： Min-feng SHI Tie ZHOU Ying WANG Guang-hua CHEN Ming ZHU Jun OU hui DU Tao-fei YAN Di SONG Ju-fen ZHENG hui-qin zhang Ning hui Ying-hao SUN Reproductive Centre Changhai Hospital the Second Military Medical University Department of Urology Changhai Hospital the Second Military Medical University

Objective To investigate the outcome of revised super-long down-regulation protocol （RSDP） for in vitro fertilization / intracytoplasmic sperm injection-embryo transfer （1VF/1CS1-ET） in the special infertile patients with repeated implantation failure （RIF）. Methods Patients with RIF were divided into RSDP group and routine long downregulation protocol （RLDP） group. In RSDP group, gonadotropin releasing hormone agonist （GnRHa） was injected intramuscularly by 2.5 mg in mid-luteal phase for the ftrst time and 1.25 mg after 28 d; gonadotropin （Gn） was started 14 d later after the second GnRHa dose. IVF/ICSI-ET was performed according to the routine procedure. The clinical outcomes of RSDP group were compared with those of RLDP group. Results In RSDP group, the number of retrieved oocytes and valid embryos was significantly lower （P〈0.05）; there were no significant differences about fertilization rate （P〉0. 05）; both good-quality embryo rate and implantation rate were significantly increased （P〈0. 005）; clinical pregnancy rate was obviously improved （P〈0. 05）, as compared with RLDP *** RSDP can improve the IVF outcomes significantly in RIF patients.

关键词： implantation failure revised super-long down-regulation protocol (RSDP) routine long protocol in vitro fertilization (IVF)

Nano high-entropy oxide cathode with enhanced stability for direct borohydride fuel cells

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Journal of Energy Chemistry 2025年第1期100卷 309-316页

作者： Lei zhang Lingfeng Kuang Lianke zhang Wen Chu Haiying qin Jing zhang Junjing He Hualiang Ni Hongzhong Chi New Energy Materials Research Center College of Materials and Environmental Engineering Hangzhou Dianzi University School of Materials Science and Engineering Zhejiang University Key Laboratory of MEMS of Ministry of Education School of Integrated Circuits Southeast University

High-entropy materials have become high-activity electrocatalysis owing to their high-entropy effect and multiple active ***,we synthesize a series of carbon-supported nano high-entropy oxides（HEOs/C）,specifically （PtFeCoNiCu）O/C,using a carbothermal shock （CTS） method for application as a cathode catalyst in direct borohydride fuel cells （DBFCs）.The microstructure of the prepared catalysts was characterized by X-ray photoelectron spectroscopy,X-ray absorption fine structure,and transmission electron *** prepared （PtFeCoNiCu）O/C,with particle sizes ranging from 2 to 4 nm,demonstrates 3.94 transferred electrons towards the oxygen reduction reaction in an alkaline environment,resulting in a minimal H2O2yield of 2.6%.Additionally,it exhibits a Tafel slope of 61 mV dec-1,surpassing that of commercial Pt/C (82 mV dec-1).Furthermore,after 40,000 cycles of cyclic voltammetry（CV） testing,the half-wave potential of （PtFeCoNiCu）O/C shows a positive shift of 3 mV,with no notable decline in the limiting current *** （PtFeCoNiCu）O/C is used as a cathode catalyst in DBFCs,the DBFC achieves a maximum power density of 441 mW cm-2at 60°C and sustains a cell voltage of approximately 0.73 V after 52 h at 30°*** findings confirm that HEO/C is a promising cathode catalyst for DBFCs.

关键词： Direct borohydride fuel cells (DBFC)