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Linear-scaling computation of excited states in time-domain

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Science China Chemistry 2014年第1期57卷 70-77页

作者： yam ChiYung CHEN GuanHua Department of Chemistry The University of Hong Kong Beijing Computational Science Research Center

The applicability of quantum mechanical methods is severely limited by their poor *** circumvent the problem,linearscaling methods for quantum mechanical calculations had been *** physical basis of linear-scaling methods is the locality in quantum mechanics where the properties or observables of a system are weakly influenced by factors spatially far *** the substantial efforts spent on devising linear-scaling methods for ground state,there is also a growing interest in the development of linear-scaling methods for excited *** review gives an overview of linear-scaling approaches for excited states solved in real time-domain.

关键词： linear-scaling methods,quantum chemistry,time-domain,density matrix

Nematogenic and smectogenic liquid crystals from new heterocyclic isoflavone derivatives:Synthesis,characterization and X-ray diffraction studies

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Chinese Chemical Letters 2011年第2期22卷 229-232页

作者： Wan Sinn yam Guan Yeow Yeap Liquid Crystal Research Laboratory School of Chemical SciencesUniversiti Sains MalaysiaMinden 11800Malaysia

A new series of liquid crystals comprising eight heterocyclic isoflavone esters,7-alkanoyloxy-3-[4＇-（3-methylbutyloxyphenyl）]- 4H-1-benzopyran-4-ones exhibiting enantiotropic nematic（N） and smectic C（SmC） phases were synthesized and *** mesomorphic properties of all derivatives were investigated by means of differential calorimetry and polarized optical microscopy. Wide angle X-ray diffraction technique was employed to investigate the molecular packing associated with the intermolecular interaction as well as the correlation between the thermal behaviour of these compounds with their anisotropy properties within a mesophase.

关键词： Heterocyclic Isoflavone Enantiotropic Mesophase

Role of Small Extracellular Vesicles in Liver Diseases:Pathogenesis,Diagnosis,and Treatment

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Journal of Clinical and Translational Hepatology 2022年第6期10卷 1176-1185页

作者： Tingmao Xue Judy Wai Ping yam Department of Hepatobiliary Surgery II Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdongChina Department of Pathology School of Clinical MedicineLi Ka Shing Faculty of MedicineThe University of Hong KongHong KongChinaReceived

Extracellular vesicles(EVs)are vesicular bodies that bud off from the cell membrane or are secreted virtually by all cell *** EVs(sEVs or exosomes)are key mediators of cell-cell communication by delivering their cargo,including proteins,lipids,or RNAs,to the recipient cells where they induce changes in signaling pathways and phenotypic *** findings have revealed the pivotal involve-ment of sEVs in the pathogenesis of various *** the bright side,they are rich sources of biomarkers for diag-nosis,prognosis,treatment response,and disease *** have high stability,biocompatibility,targetability,low toxicity,and are immunogenic in *** intrinsic properties make sEVs an ideal delivery vehicle to be loaded with cargo for therapeutic *** diseases are a major global health *** review aims to focus on the roles and mechanisms of sEVs in the pathogenesis of liver diseases,liver injury,liver failure,and liver *** are released not only by hepatocytes but also by stromal and immune cells in the *** detection of liver disease determines the chance for cura-tive treatment and high survival of *** review focuses on the potential of circulating sEV cargo as specific and sensitive noninvasive biomarkers for the early detection and prognosis of liver *** addition,the therapeutic use of sEVs derived from various cell types is ***-though sEVs hold promise for clinical applications,there are still challenges to be overcome by further research to bring utilization of sEVs into clinical practice.

关键词： Small extracellular vesicles Liver injury Liver fibrosis Liver fail-ure Hepatocellular carcinoma Biomarkers.

SCIENCE OF WINNING SOCCER:EMERGENT PATTERN-FORMING DYNAMICS IN ASSOCIATION FOOTBALL

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Journal of Systems Science & Complexity 2013年第1期26卷 73-84页

作者： VILAR Luís ARAUJO Duarte DAVIDS keith BAR-yam Yaneer Faculty of Physical Education and Sports Lusofona University of Humanities and Technologies Faculty of Human kinetics Technical University of Lisbon SpertLab CIPERFaculty of Human KineticsTechnical University of Lisbon School of Human Movement Studies Queensland University of Technologies New England Complex Systems Institute

Quantitative analysis is increasingly being used in team sports to better understand performance in these stylized,delineated,complex social ***,the authors provide a first step toward understanding the pattern-forming dynamics that emerge from collective offensive and defensive behavior in team *** authors propose a novel method of analysis that captures how teams occupy sub-areas of the field as the ball changes *** authors use this method to analyze a game of association football(soccer) based upon a hypothesis that local player numerical dominance is key to defensive stability and offensive *** authors find that the teams consistently allocated more players than their opponents in sub-areas of play closer to their own *** is consistent with a predominantly defensive strategy intended to prevent yielding even a single *** authors also find differences between the two teams' strategies:while both adopted the same distribution of defensive,midfield,and attacking players(a 4:3:3 system of play),one team was significantly more effective in maintaining both defensive and offensive numerical dominance for defensive stability and offensive *** team indeed won the match with an advantage of one goal(2 to 1) but the analysis shows the advantage in play was more pervasive than the single goal victory would *** proposed focus on the local dynamics of team collective behavior is distinct from the traditional focus on individual player *** supports a broader view in which specific player abilities contribute within the context of the dynamics of multiplayer team coordination and coaching *** applying this complex system analysis to association football,the authors can understand how players' and teams' strategies result in successful and unsuccessful relationships between teammates and opponents in the area of play.

关键词： Collective behavior performance analysis team sports.

The role of isotropic and anisotropic Hubbard corrections for the magnetic ordering and absolute band alignment of hematite α-Fe2O3(0001)surfaces

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Progress in Natural Science:Materials International 2019年第3期29卷 349-355页

作者： Sateesh Bandaru Ivan Scivetti Chi-Yung yam Gilberto Teobaldi School of Chemical and Bioprocess Engineering University College Dublin Beijing Computational Science Research Center Stephenson Institute for Renewable Energy Department of ChemistryThe University of Liverpool Scientific Computing Department Science and Technology Facilities CouncilDaresbury Laboratory

An isotropic (+U) and anisotropic [+(U-J)] corrected Density Functional Theory study for bulk hematite (α-Fe2O3) was carried out,and several competing terminations of its (0001) surface modeled via slabs of increasing thickness from twelve to thirty-six *** spite of small quantitative differences,the use of either U or (U-J)corrections showed not to qualitatively affect the results of the simulations both for bulkα-Fe2O3and the lowestenergyα-Fe2O3(0001) surface studied,regardless of the thickness of the slab *** energy favored antiferromagnetic ordering of bulkα-Fe2O3was preserved in the relaxed slabs,with the largest surface-induced effects limited to the outermost three Fe-layers in the *** O-and Fe-terminations were found to be energetically favored and ***,fully O-or Fe-terminated surfaces were calculated to be energetically disfavored and ***,the role of Fe-or O-termination for the semiconducting or metallic nature as well as absolute band alignment ofα-Fe2O3(0001) surfaces was analyzed and discussed with respect to the challenges in enhancing the activity ofα-Fe2O3samples as photo-electrode for water splitting.

关键词： Hematite α-Fe2O3 Surfaces Photo-electrodes Density functional theory Electronic properties Magnetic properties

Eradication of malaria through genetic engineering:the current situation

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Asian Pacific Journal of Tropical Medicine 2013年第2期6卷 85-94页

作者： Wing-Chui Chong Rusliza Basir yam Mun Fei Department of Human Anatomy Pharmacology UnitFaculty of Medical and Health SciencesUniversiti Putra Malaysia43400 UPM SerdangSelangorMalaysia School of Pharmaceutical Sciences Universiti Sains Malaysia11800 MindenPulau PinangMalaysia

Malaria is an intra-cellular parasitic protozoon responsible for millions of deaths *** and parasite genetic factors are crucial in affecting susceptibility to malaria and progression of the *** increased deployment of vector controls and new artemisinin combination therapies have dramatically reduced the mortality and morbidity of malaria ***, the gradual emergence of parasite and mosquito resistance has raised alarm regarding the effectiveness of current artemisinin-based *** this review,mechanisms of anti-malarial drug resistance in the Plasmodium parasite and new genetically engineered tools of research priorities are *** complexity of the parasite lifecycle demands novel interventions to achieve global ***,turning laboratory discovered transgenic interventions into functional products entails multiple experimental phases in addition to ethical and safety *** over the regulatory status and public acceptance further discourage the implementation of genetically modified organisms.

关键词： Malaria Vector control Resistance Plasmodium parasite Genetically engineered tools

The cytoplasmic droplet may be indicative of sperm motility and normal spermiogenesis

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Asian Journal of Andrology 2013年第6期15卷 799-805,I0009页

作者： Hui Xu Shui-Qiao Yuan Zhi-Hong Zheng Wei yam Department of Laboratory Animal Medicine China Medical University Shenyang 110001 China and Department of Physiology and Cell Biology University of Nevada School of Medicine Reno NV 89557 USA

Although the cytoplasm of spermatids is removed at the end of spermiogenesis, a tiny portion is usually retained in the sperm flagellum, which is termed the cytoplasmic droplet （CD） in mammals. CDs are believed to play a role in sperm volume adaptation. However, we have noticed that epididymal spermatozoa that display initial （flagellation in situ） and progressive motility mostly possess CDs, whereas spermatozoa without CDs are rarely motile, suggesting that CDs have a role in motility development during sperm epididymal maturation. In the present study, we analyzed the relationship between the presence or absence of CDs, motility development and positional changes of CDs during sperm epididymal maturation in mice and monkeys. We also examined CDs on spermatozoa of three knockout mouse lines with late spermiogenic defects. Our data suggest that the CD is a normal organelle transiently present exclusively on epididymal spermatozoa, and normal CD morphology and location are associated with normal motility development during epididymal maturation of spermatozoa. Abnormal CD formation, e.g., a complete lack of CDs or ectopic CDs, is indicative of defective spermiogenesis. If CDs are essential for sperm motility development, then CDs may represent an ideal drug target for the development of non-hormonal male contraceptives.

关键词： cytoplasmic droplets epididymis fertility mouse semen analysis spermiogenesis sperm motility

Appended corrole manganese complexes:Catalysis and axial-ligand effect

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Chinese Chemical Letters 2014年第4期25卷 571-574页

作者： Nga-Chun Ng Mian HR Mahmood Chi-k.Chang Hai-Yang Liu Fei yam Lam-Lung Yeung Department of Chemistry and Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis Hong Kong University of Science and Technology Department of Chemistry South China University of Technology Department of Chemistry Michigan State University Chi-k.Changa

A series of N-base appended corroles and their manganese complexes were synthesized and their binding constants with three different nitrogenous ligands, triethylamine, N-methylimidazole and pyridine, were evaluated by spectroscopy. kinetic studies indicated that the presence of appended N- donor ligands may cause a significant enhancement of the rate of oxygen atom transfers （OAT） from （oxo）manganese（V） corrole to alkene, and the stronger axial ligand binding has impact on the rate of the oxidation reaction. Turnover frequency （TOF） for the catalytic oxidation of alkenes by appended manganese corroles varies with the following ligand order： acetamido 〈 pyridyl 〈 imidazolyl. The influence of the external axial ligands on the catalytic epoxidation was investigated by using appended acetamido manganese corrole as catalyst, with the results revealing that N-methylimidazole gave the best enhancement on the yields of total oxidation products among the investigated nitrogenous ligands.

关键词： Manganese Corrole Catalysis Axial-ligand Oxygen atom transfer

Andrographolide effect on both Plasmodium falciparum infected and noninfected RBCs membranes

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Asian Pacific Journal of Tropical Medicine 2015年第7期8卷 505-510页

作者： Zaid O Ibraheem Abd Majid R Sabariah MN Hasidah MS Al-Zihiry k.yam.MF Basir R Pharmacology Unit Department of Human Anatomy Faculty of Medicine and Health Sciences Universiti Putra Malaysia Department of Medical Microbiology and Parasitology Faculty of Medicine and Health Sciences Universiti Putra Malaysia Department of Hematology Faculty of Medicine and Health Sciences Universiti Putra Malaysia School of Bioscience and Biotechnology Faculty of Science and Technology Universiti Kebangsaan Malaysia School of pharmaceutical science Universiti Sains Malaysia

Objective: To explore whether its antiplasmodium effect of andrographolide is attributed to its plausible effect on the plasma membrane of both Plasmodium falciparum infected and noninfected RBCs. Methods: Anti-plasmodium effect of andrographolide against Plasmodium falciparum strains was screened using the conventional malaria drug sensitivity assay. The drug was incubated with uninfected RBCs to monitor its effect on their morphology, integrity and osmotic fragility. It was incubated with the plasmodium infected RBCs to monitor its effect on the parasite induced permeation pathways. Its effect on the potential of merozoites to invade new RBCs was tested using merozoite invasion assay. Results: It showed that at andrographolide was innocuous to RBCs at concentrations approach its therapeutic level against plasmodia. Nevertheless, this inertness was dwindled at higher concentrations. Conclusions: In spite of its success to inhibit plasmodium induced permeation pathway and the potential of merozoites to invade new RBCs, its anti-plasmodium effect can't be attributed to these functions as they were attained at concentrations higher than what is required to eradicate the parasite. Consequently, other mechanisms may be associated with its claimed actions.

关键词： Andrographolide Terpenoid Plasmodium falciparum Merozoites Permeation & Osmotic fragility