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Distribution of a Certain Partition Function Modulo Powers of Primes

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Acta Mathematica Sinica,English Series 2011年第4期27卷 625-634页

作者： Hei-Chi chan Department of Mathematical Sciences University of Illinois at Springfield Springfield IL 62703-5407 USA

In this paper, we study a certain partition function a（n） defined by ∑n≥0 a（n）qn ：= ∏n=1（1- qn）-1（1 -2n）-1. We prove that given a positive integer j 〉 1 and a prime m _〉 5, there are infinitely many congruences of the type a（An ＋ B） ≡ 0 （rood m3）. This work is inspired by Ono＇s ground breaking result in the study of the distribution of the partition function p（n）.

关键词： Distribution of partition function Ono's theorem Ramanujan's congruences

The evolution and refinement of vasoepididymostomy techniques

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Asian Journal of Andrology 2013年第1期15卷 49-55页

作者： Peter T chan Department of Urology Royal Victoria Hospital McGill University Health Center Montreal Quebec H3A 1A1 Canada

Obstructive azoospermia secondary to epididymal obstruction can be corrected by microsurgical reconstruction with vasoepididymostomy （VE）. Although alternative management such as epididymal or testicular sperm aspiration in conjunction with intracytoplasmic sperm injection is feasible, various studies have established the superior cost-effectiveness of VE as a treatment of choice. Microsurgical VE is considered one of the most technically challenging microsurgeries. Its success rate is highly dependent on the skills and experience of the surgeons. Various techniques have been described in the literature for VE. We have pioneered a technique known as longitudinal intussusception VE （LIVE） in which the epididymal tubule is opened longitudinally to obtain a larger opening to allow its tubular content to pass through the anastomosis. Our preliminary data demonstrated a patency rate of over 90%. This technique has been widely referenced in the recent literature including robotic-assisted microsurgery. The history of the development of different VE approaches, the oreoDerative evaluation along with the techniaues of various VE will be described in this article.

关键词： longitudinal intussusception vasoepididymostomy (LIVE) intracytoplasmic sperm injection (ICSI) male infertility microsurgery obstructive azoospermia vasoepididymostomy (VE)

Novel roles of Skp2 E3 ligase in cellular senescence,cancer progression,and metastasis

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癌症 2012年第4期31卷 169-177页

作者： Chia-Hsin chan Department of Molecular and Cellular Oncology The University of Texas MD Anderson Cancer CenterHoustonTX 77030USA

S-phase kinase-associated protein 2 (Skp2) belongs to the F-box protein *** is a component of the SCF E3 ubiquitin ligase ***2 has been shown to regulate cellular proliferation by targeting several cell cycle-regulated proteins for ubiquitination and degradation,including cyclin-dependent kinase inhibitor ***2 has also been demonstrated to display an oncogenic function since its overexpression has been observed in many human *** review discusses the recent discoveries on the novel roles of Skp2 in regulating cellular senescence,cancer progression,and metastasis,as well as the therapeutic potential of targeting Skp2 for human cancer treatment.

关键词： Skp2 p53 RhoA cellular senescence metastasis cancer therapy

Security Framework for RFID-based Applications in Smart Home Environment

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射频世界 2012年第4期 72-76页

作者： Divyan M. Konidala Daeyoung Kim chan Yeob yeun Byoungcheon Lee

Can cold dark matter paradigm explain the central-surface-densities relation?

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Research in Astronomy and Astrophysics 2017年第7期17卷 109-114页

作者： Man-Ho chan Department of Science and Environmental Studies The Education University of Hong Kong

Recently, a very strong correlation between the central surface density of stars and dynamical mass in 135 disk galaxies has been obtained. It has been shown that this central-surface-densities relation agrees very well with Modified Newtonian Dynamics（MOND）. In this article, we show that if we assume the baryons have an isothermal distribution and dark matter exists, then it is possible to derive by means of the Jeans equation an analytic central-surface-densities relation connecting dark matter and baryons that agrees with the observed relation. We find that the observed central-surface-densities relation can also be accommodated in the context of dark matter provided the latter is described by an isothermal profile. Therefore, the observed relation is consistent with not only MOND.

关键词： (cosmology:) dark matter

Mathematical Models of Logistics Decision in Slab Yard in an Iron and Steel Complex

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 301-304页

作者： Sujian Li Zhiming chan Mechanical Engineering School University of Science and Technology BeijingBeijing 100083China Hot Strip Mill Plant of Wuhan Iron&Steel(Group)Corp. Wuhan 430083China

The slab yard in a hot strip rolling mill is a key link and a buffer in the production system, which joins continuous rolling process and continuous casting process. There are a large quantity of operations of input and output in the slab yard. Throughout systematic analysis and research on the slab yard, the mathematical models of logistics decision for input, output and restorage operation are built. On the basis of these decision models, the management system for the slab yard is developed. Simulation application to Human Iron & Steel Complex of China shows that they are very effective.

关键词： logistics slab yard model

Cambrian integrative stratigraphy and timescale of China

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Science China Earth Sciences 2019年第1期62卷 25-60页

作者： Maoyan ZHU Aihua YANG Jinliang YUAN Guoxiang LI Junming ZHANG Fangchen ZHAO Soo-yeun AHN Lanyun MIAO State Key Laboratory of Palaeobiology and Stratigraphy & Center for Excellence in Life and Paleoenvironment Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences College of Earth Sciences University of Chinese Academy of Sciences Centre for Research and Education on Bilogical Evolution and Environment Nanjing University

The Cambrian Period is the first period of the Phanerozoic Eon and witnessed the explosive appearance of the metazoans, representing the beginning of the modern earth-life system characterized by animals in contrary to the Precambrian earth-life system dominated by microbial life. However, understanding Cambrian earth-life system evolution is hampered by regional and global stratigraphic correlations due to an incomplete chronostratigraphy and consequent absence of a highresolution timescale. Here we briefly review the historical narrative of the present international chronostratigraphic framework of the Cambrian System and summarize recent advances and problems of the undefined Cambrian stage GSSPs, in particular we challenge the global correlation of the GSSP for the Cambrian base, in addition to Cambrian chemostratigraphy and geochronology. Based on the recent advances of the international Cambrian chronostratigraphy, revisions to the Cambrian chronostratigraphy of China, which are largely based on the stratigraphic record of South China, are suggested, and the Xiaotanian Stage is newly proposed for the Cambrian Stage 2 of China. We further summarize the integrative stratigraphy of South China, North China and Tarim platforms respectively with an emphasis on the facies variations of the Precambrian-Cambrian boundary successions and problems for identification of the Cambrian base in the different facies and areas of China. Moreover, we discuss stratigraphic complications that are introduced by poorly fossiliferous dolomite successions in the upper Cambrian System which are widespread in South China, North China and Tarim platforms.

关键词： Cambrian Stratigraphy Golden Spike GSSP Geochronology South China North China Tarim

Evolution of microstructure and tensile properties of cold-drawn hyper-eutectoid steel wires during post-deformation annealing

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Journal of Materials Science & Technology 2020年第6期41卷 1-11页

作者： Majid Jafari chan-Woo Bang Jong-chan Han Kyeong-Min Kim Seon-Hyeong Na chan-Gyung Park Byeong-Joo Lee Department of Materials Science and Engineering POSTECH Pohang 37673 South Korea

Manufacturing temperatures of severely cold-drawn hyper-eutectoid steel wires are sufficiently high to influence the mobility of dislocations and alloy elements,thereby affecting the materials’mechanical ***,we describe the evolution of microstructure and tensile strength of the as-drawn 3.45 GPa steel wire during post-deformation annealing for 30 min at 150-450℃.Annealing at 150℃raised the strength to 3.77 GPa by age-hardening through activation of dislocations pinning by carbon,while further temperature rising up to 450℃caused a severe loss of *** was proved that annealing at 300 and 450℃destabilizes the lamellar microstructure,promoting the formation of carbon-deficient(Fe,Mn,Cr)3 C-type cementite particles with preferentially rounded and partially faceted *** at 450℃yielded the accumulation of Mn and Cr at the ferrite/particle interfaces,and their concentrations at the interfaces were dependent on the interface structure;i.e.,lower concentrations at rounded interfaces(formed through capillarity–driven coarsening of the spheroidized cementite),and higher concentrations at faceted interfaces(that are initially existing in the as-drawn state).Our proof-of-principle observations,supported by thermodynamic calculations and kinetic assessments,provide a pathway for understanding the changes in microstructural and tensile properties during manufacturing of the hyper-eutectoid steel wires.

关键词： Three-dimensional atom probe(3DAP) High resolution transmission electron microscopy(HRTEM) Nano-grained low-carbon steel Annealing Tensile behavior

Urocortin and cardiovascular protection

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Acta Pharmacologica Sinica 2004年第3期25卷 3-11页

作者： Chi-wai LAU,Yau-chi chan,Suk-ying TSANG,Franky Leung chan The Chinese University of Hong Kong Hong Kong China Department of Anatomy The Chinese University of Hong Kong Hong Kong China Department of Anatomy The Chinese University of Hong Kong Hong Kong China Department of Anatomy The Chinese University of Hong Kong Hong Kong China Department of Anatomy

Urocortin and other hypothalamus corticotropin-releasing factor (CRF) polypeptides play biologically diverse roles in the stress, cardiovascular and inflammatory responses by acting on central and peripheral CRF receptors. Urocortin shows a significantly high sequence homology to CRF, and the concurrent expression of type-2 CRF (CRF2) receptors with urocortin in the heart suggests that urocortin may play a physiological role in the cardiac function. Urocortin is thought to be the endogenous agonist producing the cardiovascular actions previously attributed to CRF. This review highlights the current novel findings on the molecular and cellular mechanisms by which urocortin may exert its cardiovascular protective action.

关键词： urocortin corticotropin-releasing hormone vascular smooth muscle heart vasodilaion second messenger system protein kinases