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Review of Feynman’s Path Integral in Quantum statistics:from the Molecular schrödinger Equation to Kleinert’s Variational Perturbation Theory

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Communications in Computational Physics 2014年第4期15卷 853-894页

作者： Kin-yiu wong Department of Physics High Performance Cluster Computing CentreInstitute of Computational and Theoretical StudiesHong Kong Baptist University224 Waterloo RoadKowloon TongHong Kong Institute of Research and Continuing Education Hong Kong Baptist University(Shenzhen)

Feynman’s path integral reformulates the quantum schrödinger differential equation to be an integral *** has been being widely used to compute internuclear quantum-statistical effects on many-body molecular *** this Review,the molecular schrödinger equation will first be introduced,together with the BornOppenheimer approximation that decouples electronic and internuclear *** effective semiclassical potentials,e.g.,centroid potential,which are all formulated in terms of Feynman’s path integral,will be discussed and *** semiclassical potentials can be used to directly calculate the quantum canonical partition function without individual schrödinger’s energy *** a result,path integrations are conventionally performed with Monte Carlo and molecular dynamics sampling *** complement these techniques,we will examine how Kleinert’s variational perturbation(KP)theory can provide a complete theoretical foundation for developing non-sampling/non-stochastic methods to systematically calculate centroid *** enable the powerful KP theory to be practical for many-body molecular systems,we have proposed a new path-integral method:automated integrationfree path-integral(AIF-PI)*** to the integration-free and computationally inexpensive characteristics of our AIF-PI method,we have used it to perform ab initio path-integral calculations of kinetic isotope effects on proton-transfer and RNA-related phosphoryl-transfer chemical *** computational procedure of using our AIF-PI method,along with the features of our new centroid path-integral theory at the minimum of the absolute-zero energy(AMAZE),are also highlighted in this review.

关键词： Feynman’s path integral Kleinert’s variational perturbation theory schrödinger’s equation quantum statistics centroid potential energy quantum tunneling zero-point energy isotope effects

surgery in the age of biologics

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Gastroenterology Report 2019年第2期7卷 77-90,I0001页

作者： Daniel J.wong Eve M.Roth Joseph D.Feuerstein Vitaliy y.Poylin Department of surgery Division of Colon&Rectum SurgeryBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMassachusettsUSA Department of Medicine Division of GastroenterologyBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMassachusettsUSA

since the introduction of the first anti-tumor necrosis factor antibodies in the late 1990s,biologic therapy has revolutionized the medical treatment of patients with inflammatory bowel disease(IBD).Nevertheless,surgery continues to play a significant role in treating IBD *** of intestinal resection in patients with Crohn’s disease or colectomy in ulcerative colitis are reducing but not substantially over the long *** increasing variety of biologic medications are now available to treat IBD patients in various clinical ***,a number of questions persist about how biologic medications affect the need for surgery and overall course in IBD *** the trend for earlier and more frequent use of biologic medications in IBD patients,a working knowledge of the effects of these medications on surgical decision-making and outcomes is essential for the practicing colorectal surgeon and *** review seeks to summarize the relevant literature surrounding biologic use and IBD surgery with a focus on the effect of biologics on the frequency,type and complications of surgery in this‘age of biologics’.

关键词： Biologics inflammatory bowel disease surgery review

High-contrast,fast chemical imaging by coherent Raman scattering using a self-synchronized two-colour fibre laser

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Light(science & Applications) 2020年第1期9卷 1775-1786页

作者： Cihang Kong Christian Pilger Henning Hachmeister Xiaoming Wei Tom H.Cheung Cora s.W.Lai Nikki P.Lee Kevin K.Tsia Kenneth K.y.wong Thomas Huser Department of Electrical and Electronic Engineering The University of Hong KongPokfulam RoadHong KongChina Biomolecular Photonics Department of PhysicsUniversity of BielefeldUniversitatsstr2533615 BielefeldGermany Division of Life science The Hong Kong University of Science and TechnologyHong KongChina Department of Physiology Li Ka Shing Faculty of MedicineThe University of Hong KongPokfulamHong KongChina Department of surgery The University of Hong KongPokfulam RoadHong KongChina Division of Engineering and Applied science California Institute of Technology1200 East California BoulevardPasadenaCA 91125USA

Coherent Raman scattering(CRs)microscopy is widely recognized as a powerful tool for tackling biomedical problems based on its chemically.s.ecific label-free contrast,high spatial and spectral resolution,and high ***,the clinical translation of CRs imaging technologies has long been hindered by traditional solid-state lasers with environmentally.s.nsitive operations and large *** fibre lasers can potentially overcome these shortcomings but have not yet been fully exploited for CRs imaging,as previous implementations have suffered from high intensity noise,a narrow tuning range and low power,resulting in low image qualities and slow imaging ***,we present a novel high-power self-synchronized two-colour pulsed fibre laser that achieves excellent performance in terms of intensity.s.ability(improved by 50 dB),timing jitter(24.3 fs),average power fluctuation(20 dB)and pulse width variation(satility of the laser source enables,for the first time,high-contrast,fast CRs imaging without complicated noise reduction via balanced detection *** capabilities are demonstrated in this work by imaging a wide range of species such as living human cells and mouse arterial tissues and performing multimodal nonlinear imaging of mouse tail,kidney and brain tissue sections by utilizing second-harmonic generation and twophoton excited fluorescence,which provides multiple optical contrast mechanisms simultaneously and maximizes the gathered information content for biological visualization and medical *** work also establishes a general scenario for remodelling existing lasers into synchronized two-colour lasers and thus promotes a wider popularization and application of CRs imaging technologies.

关键词： scattering tuning fibre

Is aggregated oviposition by the blow flies Lucilia sericata and Phormia regina （Diptera： Calliphoridae） really pheromone-mediated？

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Insect science 2015年第5期22卷 651-660页

作者： Bekka s. Brodie Warren H. L. wong sherah VanLaerhoven Gerhard Gries simon Fraser University Dept. of Biological Sciences Burnaby BC V5A 1S6 Canada and University of Windsor Windsor ON N9B3P4 Canada

When female blow flies Lucilia sericata and Phormia regina （Diptera： Cal- liphoridae） oviposit in aggregations on carrion, even-aged larval offspring reportedly de- velop faster, and fewer are parasitized or preyed upon. The benefits of aggregated ovipo- sition equally affect con- and heterospecific larvae sharing a resource. The benefits imply that female blow flies engage in coordinated, pheromone-mediated oviposition behavior. yet, repeated attempts to identify oviposition pheromones have failed invoking doubt that they exist. simply by regurgitating and feeding on carrion, flies may produce attractive semiochemicals. If flies were to aggregate in response to feeding flies rather than oviposit- ing flies, then the semiochemical cue（s） may be associated with the salivary gland. Working with L. sericata and P.. regina and using liver as a surrogate oviposition medium, we test the hypotheses, and present data in their support, that （i） gravid or nongravid females ovipositing and/or feeding on liver enhance its attractiveness to gravid and nongravid fe- males; （ii） females respond to semiochemicals from feeding heterospecific females; （iii） females respond equally well to semiochemicals from feeding con- and heterospecific females; （iv） macerated head tissues of females applied to liver enhance its attractiveness; and （v） females in direct contact with and feeding on liver, but not when next to yet physically.s.parated from liver, enhance attraction of flies. We conclude that oviposition site-seeking females do not respond to an oviposition pheromone. Instead, they appear to coopt semiochemicals associated with feeding flies as resource indicators, taking chances that resources are suitable for oviposition, and that ovipositing flies are present.

关键词： blow flies carrion egg-laying site pheromone saliva semiochemical

Disease Biomarkers for Precision Medicine:Challenges and Future Opportunities

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Genomics, Proteomics & Bioinformatics 2017年第2期15卷 57-58页

作者： Edwin Wang William C.s.Cho s.C.Cesar wong siqi Liu Center for Health Genomics and Informatics University of Calgary Cumming School of Medicine Department of Clinical Oncology Queen Elizabeth Hospital Department of Health Technology and Informatics Faculty of Health and Social Sciences Hong Kong Polytechnic University CAs Key Laboratory of Genome sciences and Information Beijing Institute of Genomics Chinese Academy of Sciences

Most of the human diseases are complex diseases,which could be caused by many genetic *** means that for a given phenotype(i.e.,a complex disease),there are multiple potential genes which could be genomically or epigenetically changed(i.e.,mutations,copy number variations,epigenetic modifications,and so on).Therefore,it is understandable that different individuals who share the same phenotype/diseases may have different causal genes and thus,may have different drug *** example,mutated genes are rarely common between the cancer patients of the same cancer type[1];furthermore,for a given drug,only 10%-30% of the patients

关键词： data Disease Biomarkers for Precision Medicine:Challenges and Future Opportunities

低相变温度垂直取向的CoPtCu/Ag纳米复合膜

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物理学报 2007年第6期56卷 3533-3538页

作者：薛双喜王浩 s.P.wong 台州学院物理与电子工程学院临海317000 湖北大学物理学与电子技术学院暨纳米技术研究中心武汉430062 香港中文大学电子工程系

采用磁控溅射(Ag/Cu/CoPt)n多层膜先驱体结合真空退火的方法制备了一系列CoPtCu/Ag纳米复合薄膜,通过优化薄膜中Ag以及Cu的含量,成功制备出了低相变温度垂直取向的CoPtCu/Ag纳米复合膜,该膜在450℃退火即可发生相变,该温度比目前所报导... 详细信息

采用磁控溅射(Ag/Cu/CoPt)n多层膜先驱体结合真空退火的方法制备了一系列CoPtCu/Ag纳米复合薄膜,通过优化薄膜中Ag以及Cu的含量,成功制备出了低相变温度垂直取向的CoPtCu/Ag纳米复合膜,该膜在450℃退火即可发生相变,该温度比目前所报导的CoPtAg纳米复合膜的相变温度降低了150℃.实验结果表明,薄膜中一定含量的Ag元素能够有效诱导薄膜的(001)取向,Cu元素的加入能有效降低薄膜的有序化温度.对于特定组分为Co40Pt36Cu8Ag16的薄膜,经500℃退火后已经显示了明显的(001)取向,垂直于膜面方向上的矫顽力为5.0×105A/m,并且薄膜中晶粒尺寸仅为4—5nm,为将来CoPt-L10有序相合金薄膜用于超高密度垂直磁记录介质打下了基础.

关键词：磁记录材料 CoPt 纳米复合膜

An old weapon with a new function:PIWI-interacting RNAs in neurodegenerative diseases

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Translational Neurodegeneration 2021年第1期10卷 91-111页

作者： Xiaobing Huang Garry wong Centre of Reproduction Development and AgingFaculty of Health SciencesUniversity of MacaoMacao 999078S.A.R.China

PlWI-interacting RNAs(piRNAs)are small non-coding transcripts that are highly conserved across species and regulate gene expression through pre-and post-transcriptional *** were originally discovered in germline cells and protect against transposable element expression to promote and maintain genome *** the recent decade,emerging roles of piRNAs have been revealed,including the roles in sterility,tumorigenesis,metabolic homeostasis,neurodevelopment,and neurodegenerative *** this review,we summarize piRNA biogenesis in ***,Drosophila,and mice,and further elaborate upon how piRNAs mitigate the harmful effects of ***,the most recent findings on piRNA participation in neurological diseases are *** speculate on the mechanisms of piRNA action in the development and progression of neurodegenerative *** the roles of piRNAs in neurological diseases may facilitate their applications in diagnostic and therapeutic practice.

关键词： piRNA piRNA biogenesis Transposable element Neurodegenerative disease H3K9me3

Femtosecond Degenerate Four-Wave-Mixing in ZnO Microcrystallite Thin Films

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Chinese Physics Letters 1999年第6期16卷 418-419页

作者： ZHANG Wei-li WANG Qing-yue CHAI Lu XING Qi-rong K.s.wong H.Wang Z.K.Tang G.K.L.wong R.Jain Ultrafast Laser Laboratory School of Precision Instruments&Optoelectronics Engineeringand Optoelectronic Information Science and Technology LaboratoryTianjin UniversityTianjin 300072 school of science Tianjin UniversityTianjin 300072 Department of Physics Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong Center for High Technology Materials University of New Mexico1313 Goddard SEAlbuquerqueNM 87106USA

Transient third-order optical nonlinearityχ^(3)of ZnO microcrystallite thin films is measured at various temperatures by using femtosecond degenerate ***-temperature excitonic enhancement of is *** magnitude ofχ^(3)ranges between 10^(-4)to 10^(-6)esu from 4.2K to room *** measuredχ^(3)response time ranging from 200 to 300 fs ultrafast for temperature down to 4.2K.

关键词： temperature. crystallite nonlinearity

UsERs′ PERCEPTION OF KOWLOON PARK, HONG KONG:VIsITING PATTERNs AND sCENIC AsPECTs

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Chinese Geographical science 2004年第3期14卷 269-275页

作者： wong Koon-kwai Manfred DOMROEs Geography Department Hong Kong Baptist University Hong Kong P. R. ChinaGeography Department Mainz University 55099 Mainz Germany

Hong Kong is a hyper-dense city with 7x10(6) people living in an area of 1100km(2). One way to improve the livability of compacted and congested cities like Hong Kong is through the provision of urban parks, an aspect that has largely been under-researched. This study focuses on how users perceive and utilize various facilities in the Kowloon Park. The findings revealed that the Kowloon Park is one of the most preferred parks in Hong Kong for both local residents and tourists. Users were quite satisfied with the park's facilities. Notably, the most important component of an urban park is its greenery. This is followed by water elements, seating places, and facilities for various recreational activities. The improvements users would like to see in urban parks include good design and management, meeting users' needs, overcoming barriers to use, and providing a high quality and varied experience for different groups in the community. The findings of this study provide a good basis to address park management issues from the users' perspective. In particular, parks should provide easy access, encourage optimum usage and enable complimentary improvements to the environment.

关键词： urban park visiting pattern user perception urban park management