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具混合边界的双曲微分方程在L^p(0,T;W^(1,p)(?))空间中的研究（英文）

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数学杂志 2017年第3期37卷 598-612页

作者：魏利 RAVI P.AGARWAL patricia j.y.wong 河北经贸大学数学与统计学学院河北石家庄050061 Department of Mathematics Texas A&M University-Kingsville Department of Mathematics Faculty of ScienceKing Abdulaziz University School of Electrical and Electronic Engineering Nanyang Technological University

本文研究了一类具混合边界的一般形式的双曲微分方程.利用分裂方程和Neumann边界条件的方法,借助于定义非线性算子,并利用Reich关于极大单调算子值域几乎相等的结论检验所定义算子具备某些性质的技巧,获得了双曲边值问题在L^p(0,T;W^(1,... 详细信息

本文研究了一类具混合边界的一般形式的双曲微分方程.利用分裂方程和Neumann边界条件的方法,借助于定义非线性算子,并利用Reich关于极大单调算子值域几乎相等的结论检验所定义算子具备某些性质的技巧,获得了双曲边值问题在L^p(0,T;W^(1,p)(?))空间中存在唯一解的结果.基于双曲方程中的主项是非线性的,所以本文应用了新的证明技巧,推广和补充了以往的相关工作.

关键词：严格单调算子次微分迹算子值域几乎相等双曲方程

Mechanosynthesis and mechanochemical treatment of bismuth-doped vanadium phosphorus oxide catalysts for the partial oxidation of n-butane to maleic anhydride

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journal of Natural Gas Chemistry 2008年第3期17卷 232-237页

作者： y. H. Taufiq-yap y.C. wong y. Kamiya W.j. Tang Putra Center for Catalysis Science and Technology Department of Chemistry Faculty of Science Universiti Putra Malaysia 43400 UPM Serdang Selangor Darul Ehsan Malaysia Graduate School of Environmental Science Hokkaido Universit3 Sapporo 060-0810 Japan

Three Bi-doped vanadyl pyrophosphate catalysts were prepared via dihydrate route （VPD method）, which consisted of different preparation methods including mechanosynthesis, mechanochemical treatment, and the conventional reflux method. The catalysts produced by the above three methods were characterized by x-ray diffraction （XRD）, scanning electron microscopy （SEM）, and temperature programmed reduction （TPR）. Catalytic evaluation for the partial oxidation of n-butane to maleic anhydride （MA） was also carried out. The XRD patterns of all the Bi-doped catalysts showed the main peaks of pyrophosphate phase. Lower intensity peaks were observed for the mechanochemically treated Bi-doped catalyst （VPDBiMill） with two additional small peaks corresponding to the presence of a small amount of V5＋ phase. The TPR profiles showed that the highest amount of active oxygen species, i.e, V4＋–O- pair, responsible for n-butane activation, was removed from VPDBiMill. Furthermore, from the catalytic test results, the graph of selectivity to MA as a function of the conversion of n-butane demonstrated that VPDBiMill was the most selective catalyst. This suggests that the mechanochemical treatment of vanadium phosphate catalyst （VPDBiMill） is a potential method to improve the catalytic properties for the partial oxidation of n-butane to maleic anhydride.

关键词： mechanosynthesis mechanochemical treatment bismuth vanadyl pyrophosphate

Nitric Oxide： A Multitasked Signaling Gas in Plants

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Molecular Plant 2015年第4期8卷 506-520页

作者： patricia Domingos Ana Margarida Prado Aloysius wong Christoph Gehring jose A. Feijo Instituto Gulbenkian de Ciencia P-2780-156 Oeiras Portugal Division of Biological and Environmental Sciences and Engineering 4700 King Abdullah University of Science and Technology Thuwa123955-6900 Kingdom of Saudi Arabia Department of Cell Biology and Molecular Genetics University of Maryland 0118 BioScience Research Building College Park MD 20742-5815 USA

Nitric oxide （NO） is a gaseous reactive oxygen species （ROS） that has evolved as a signaling hormone in many physiological processes in animals. In plants it has been demonstrated to be a crucial regulator of development, acting as a signaling molecule present at each step of the plant life cycle. NO has also been implicated as a signal in biotic and abiotic responses of plants to the environment. Remarkably, despite this plethora of effects and functional relationships, the fundamental knowledge of NO production, sensing, and transduction in plants remains largely unknown or inadequately characterized. In this review we cover the current understanding of NO production, perception, and action in different physiological sce- narios. We especially address the issues of enzymatic and chemical generation of NO in plants, NO sensing and downstream signaling, namely the putative cGMP and Ca^2＋ pathways, ion-channel activity modulation, gene expression regulation, and the interface with other ROS, which can have a profound effect on both NO accumulation and function. We also focus on the importance of NO in cell-cell communication during developmental processes and sexual reproduction, namely in pollen tube guidance and embryo sac fertilization, pathogen defense, and responses to abiotic stress.

关键词： nitric oxide (NO) reactive oxygen species (ROS) plant sexual reproduction cell communication pollen

Heavy metal concentrations in edible bivalves and gastropods available in major markets of the Pearl River Delta

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journal of Environmental Sciences 2001年第2期13卷 210-217页

作者： FANG Zhan-qiang CHEUNG R.y.H. wong M.H. Department of Biology South China Normal UniversityGuangzhou 510631China Department of Biology and Chemistry City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong Institute for Natural Resources and Waste Management and Department of BiologyHong Kong Bapt ist UniversityKowloon TongHong Kong

Molluscs are able to accumulate heavy metals and impose health hazard to consumers. The main objective of the present study is to investigate the heavy metal concentrations in edible bivalves and gastropods available in major markets of the Pearl River Delta. Fourteen species of edible molluscs were purchased from six markets in Hong Kong and Guangdong Province. The fresh of these biota were tested for their cadmium (Cd), copper (Cu), zinc (Zn), lead (Pb), nickel (Ni), chromium (Cr), antimony (Sb) and tin (Sn) concentrations (based on wet weight). The results indicated that amongst the 14 edible molluscs, only Cd, Pb, Ni, Cr, Sb and Sn concentrations in three species (Ruditapes philippinarum, Perna viridis and Hemifusus tuba) were within the local regulatory limits. Over 60% of bivalve species exceeded maximum permitted levels of Cd (2 mug/g) and Cr (1 mug/g), while over 40% of gastropod species exceeded the maximum levels of Sb (1 mug/g) and Cr (1 mug/g). Most of the samples collected from Hong Kong had significantly higher contents of Pb and Sb, but similar levels of Cd, Cu and Zn when compared with samples collected across the border ( p y). In general, the molluscs purchased in Guangdong markets had higher metal contents than those purchased from the Hong Kong markets. When compared with the Provisional Tolerable Weekly Intake or Maximum Acceptable Daily Load recommended by FAO/WHO Expert Committee on Food Additives, Cd levels of five species (Anadara ferruginea, Pinna pectinata, Chlamys nobilis, Babylonia lutosa and Hemifusus terntanus) and Cr levels of seven species ( Anadara ferruginea, Paphia undulata, Pinna pectinata, Babylonia lutosa, Hemifusus terntanus, Cymbium melo and Cipangopaludina chinensis) were higher than both the human daily acceptable limits (for Cd and Cr respectively) and the local regulatory levels (for Cd and Cr respectively).

关键词： heavy metals edible molluscs human health Pearl River Delta

Are state ownership and auditors' locality determinants of asset write-downs? Evidence from China

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China journal of Accounting Research 2018年第4期11卷 385-405页

作者： Pauline W.y.wong Department of Accountancy Hang Seng Management College

After issuing the 1998 Accounting Standards, Chinese regulators implemented additional regulations in 2001 governing write-downs of impaired assets and required assessment of recoverable amounts for four additional asset categories. As the recoverable value cannot be obtained objectively, management can discretionally assess the magnitude of write-downs to affect bottom-line profit. This study used 7258 firm-year observations in China from 1998 to2005 to examine whether the percentage of asset write-downs by statecontrolled firms differs from non-state-controlled firms, conditional upon more conservative financial reporting rules, and investigate whether local auditors support managerial decisions on asset write-downs. The empirical findings support the tendency of state-controlled ownerships to have lower asset write-downs. Local auditors also support managerial decisions on asset write-downs, especially when the companies are controlled by local governments.

关键词： Earnings management Impairments State ownership Auditor locality Political influence

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

Carrier Density and Plasma Frequency of Alummum Nanofilms

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journal of Materials Science & Technology 2003年第4期19卷 365-367页

作者： HaoDU junGONG ChaoSUN RongfangHUANG lISHIWEN W.y.Cheung S.P.wong InstituteofMetalResearch ChineseAcademyofSciencesShenyang110016China TheChinsesUniversityofHongKong HongKongChina

In this work, the prerequisite and mode of electromagnetic response of Al nanof ilms to electromagnetic wave field was suggested. Reflectance, transmittance in infrared region and carrier density of the films was measured. With the carrier density of the films, the dependence of their plasma frequencies on the film thickness was obtained. On the other hand, the dependence of absorptance on the frequency of electromagnetic wave field was set up by using the measured reflectance and transmittance, which provided plasma frequency-film thickness relation as well. Similarity of both plasma frequency-film thickness relations proved plasma resonance as a mode of electromagnetic response in Al nanofilms.

关键词： Aluminum nanofilm Electromagnetic response Size effect

Effects of polydimethylsiloxane membrane surface treatments on human uterine smooth muscle cell strain response

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Bioactive Materials 2024年第2期32卷 415-426页

作者： Elizabeth E.Marr Brett C.Isenberg joyce y.wong Boston University Division of Materials Science and EngineeringUnited States Charles Stark Draper Laboratory Bioengineering DivisionUnited States Boston University Department of Biomedical EngineeringUnited States

In the United States,1 in 10 infants are born *** majority of neonatal deaths and nearly a third of infant deaths are linked to preterm *** birth is initiated when the quiescent state of the uterus ends prematurely,leading to contractions and parturition beginning as early as 32 weeks,though the origins are not well *** enable research and discovery of therapeutics with potential to better address preterm birth,the capability to study isolated cell processes of pregnant uterine tissue in vitro is *** development of an in vitro model of the myometrium utilizing human uterine smooth muscle cells(uSMCs)responsible for contractions provides a methodology to examine cellular mechanisms of late-stage pregnancy potentially involved in preterm *** discuss culture of uSMCs on a flexible polydimethylsiloxane(PDMS)substrate functionalized with cationic poly-L-lysine(PLL),followed by extracellular matrix(ECM)protein *** work exploring uSMC behavior on PDMS substrates have utilized collagen-I coatings,however,we demonstrated the first exploration of human uSMC response to strain on fibronectin-coated flexible membranes,importantly reflecting the significant increase of fibronectin content found in the myometrial ECM during late-stage *** the model we developed,we conducted proof-of-concept studies to investigate the impact of substrate strain on uSMC cell morphology and gene *** was found that PLL and varied ECM protein coatings(collagen I,collagen III,and fibronectin)altered cell nuclei morphology and density on PDMS ***,varied strain rates applied to uSMC substrates significantly impacted uSMC gene expression of IL-6,a cytokine associated with instances of preterm *** results suggest that both surface and mechanical properties of in vitro systems impact primary human uSMC phenotype and offer uSMC culture methodologies that can be utilized to further the understanding of cellu

关键词： Uterine Myometrium Bioengineered in vitro models Strain Pregnancy Nuclei Interleukin 6 Preterm labor

Role of stem cell therapies in treating chronic wounds:A systematic review

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World journal of Stem Cells 2020年第7期12卷 659-675页

作者： Anjali C Raghuram Roy P yu Andrea y Lo Cynthia j Sung Melissa Bircan Holly j Thompson Alex K wong Division of Plastic and Reconstructive Surgery Keck School of Medicine of USCLos AngelesCA 90033United States Wilson Dental Library Herman Ostrow School of Dentistry of USCLos AngelesCA 90089United States

BACKGROUND The impairment of cutaneous wound healing results in chronic,non-healing wounds that are caused by altered wound environment oxygenation,tissue injury,and permissive microbial *** modalities for the treatment of these wounds inadequately address the complex changes involved in chronic wound ***,stem cell therapies have emerged as a potential therapeutic modality to promote cutaneous regeneration through trophic and paracrine *** To investigate current literature regarding use of stem cell therapies for the clinical treatment of chronic,non-healing *** PubMed,EMBASE,Cochrane Library,Web of Science,and Scopus were queried with combinations of the search terms“mesenchymal stem cells,”“adult stem cells,”“embryonic stem cells,”“erythroid precursor cells,”“stem cell therapies,”and“chronic wounds”in order to find relevant articles published between the years of 2000 and 2019 to review a 20-year *** lists from the articles were reviewed to identify additional pertinent *** manuscripts(reviews,case reports/series,retrospective/prospective studies,and clinical trials)were evaluated by the authors for their depiction of clinical stem cell therapy *** were extracted from the articles using a standardized collection *** A total of 43 articles describing the use of stem cell therapies for the treatment of chronic wounds were included in this *** stem cell therapies have been explored in in vitro and in vivo applications in the past,recent efforts are geared towards assessing their clinical role.A review of the literature revealed that adipose-derived stem cells,bone marrow-derived stem cells,bone marrowderived mononuclear cells,epidermally-derived mesenchymal stem cells,fibroblast stem cells,keratinocyte stem cells,placental mesenchymal stem cells,and umbilical cord mesenchymal stem cells have all been employed in the treatment of chronic wounds of various etiolo

关键词： Mesenchymal stem cells Adult stem cells Embryonic stem cells Erythroid precursor cells Stem cell therapies Chronic wounds