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东亚季风降水的年际变化 被引量:15
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作者 缪锦海 k.M.lau 《应用气象学报》 CSCD 北大核心 1990年第4期377-382,共6页
通过对东亚夏季风区域30年降水量的分析研究,我们发现东亚夏季风降水年际变化中的主要成份是准二年周期变化;ENSO 与东亚夏季风降水的年际变化以及准二年周期有着明显的联系。
关键词 东亚夏季风 年际变化 东亚季风 周期变化 年周期 年降水量 距平 经验正交函数 ENSO 年降水总量
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The Aerosol-Monsoon Climate System of Asia:A New Paradigm 被引量:6
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作者 William k.M.lau 《Journal of Meteorological Research》 SCIE CSCD 2016年第1期1-11,共11页
This commentary is based on a series of recent lectures on aerosol-monsoon interactions I gave at the Beijing Normal University in August 2015. A main theme of the lectures is on a new paradigm of "An Aerosol-Monsoon... This commentary is based on a series of recent lectures on aerosol-monsoon interactions I gave at the Beijing Normal University in August 2015. A main theme of the lectures is on a new paradigm of "An Aerosol-Monsoon-Climate-System", which posits that aerosol, like rainfall, cloud, and wind, is an integral component of the monsoon climate system, influencing monsoon weather and climate on M1 timescales. Here, salient issues discussed in my lectures and my personal perspective regarding interactions between atmospheric dynamics and aerosols from both natural and anthropogenic sources are summarized. My hope is that under this new paradigm, we can break down traditional disciplinary barriers, advance a deeper understanding of weather and climate in monsoon regions, as well as entrain a new generation of geoscientists to strive for a sustainable future for one of the most complex and challenging human-natural climate sub-system of the earth. 展开更多
关键词 AEROSOL monsoon climate system INTERACTION new paradigm
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香港结核病与吸烟调查 被引量:5
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作者 C.C.Leung C.k.Chan +8 位作者 C.M.Tam k.C.Chang C.H.Chau W.S.Law W.W.Yew C.H.Chau C.W.Lam k.S.lau 贺晓新 《国际结核病与肺部疾病杂志》 2003年第4期133-138,共6页
目的:了解在香港人群中吸烟与结核病的联系。方法:利用间接调整法比较1996年报告登记的851例结核病人样本与一般人群的吸烟率。并利用分层单因素分析和多元logisitc回归分析方法比较了曾吸烟者与不吸烟者的临床特征。结果:与人群对照相... 目的:了解在香港人群中吸烟与结核病的联系。方法:利用间接调整法比较1996年报告登记的851例结核病人样本与一般人群的吸烟率。并利用分层单因素分析和多元logisitc回归分析方法比较了曾吸烟者与不吸烟者的临床特征。结果:与人群对照相比,结核病人的吸烟率较高。在16-64岁组,吸烟与结核病之间的比值比(OR)在男性和女性分别为2.44和2.08(Mantel-Haenszel加权OR=2.40,P<0.001);在65岁以上组,则分别为 2.09和2.83(Mantel-Haenszel加权 OR=2.19,P<0.001)。男性、65岁以上、发病时仍在工作、经 常饮酒、吸毒以及无结核病接触史等与吸烟有关(P<0.05)。曾吸烟者的咳嗽比例高(OR=1.69)、容易憋气(OR=1.84)、上肺区受累多(OR=1.67)、易发空洞(OR=1.76)和粟粒性肺结核(OR=2.77)以及痰菌培养阳性的概率较大(OR=1.43),但发生孤立肺外结核病的机会要小(OR=0.31),即使控制了背景因素的混杂作用后也如此(P<0.05)。结论:吸烟与结核病有关。严重类型的肺结核多见于曾吸烟者。 展开更多
关键词 吸烟 结核病 男性 年长者
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Phase Transformation and Thermal Stability of Aged Ti-Ni-Hf High Temperature Shape Memory Alloys 被引量:2
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作者 Xianglong MENG Wei CAI +2 位作者 k.T.lau L.M.Zhou Liancheng ZHAO 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第5期691-695,共5页
The use of Ni-rich TiNiHf alloys as high temperature shape memory alloys (SMAs) through aging has been presented. For Ni-rich Ti80-xNixHf20 alloys, their phase transformation temperatures are averagely increased mor... The use of Ni-rich TiNiHf alloys as high temperature shape memory alloys (SMAs) through aging has been presented. For Ni-rich Ti80-xNixHf20 alloys, their phase transformation temperatures are averagely increased more than 100 K by aging at 823 K for 2 h. Especially for the alloys with Ni-content of 50.4 at. pct and 50.6 at. pct, their martensitic transformation start temperatures (Ms) are more than 473 K after aging. TEM observation confirmed that some fine particles precipitate from the matrix during aging. The aged Ni-rich TiNiHf SMAs show the better thermal stability of phase transformation temperatures than the solutiontreated TiNiHf alloys. The fine particles precipitated during aging should be responsible for the increase of phase transformation temperatures and its high stability. 展开更多
关键词 TiNiHf alloy High temperature shape memory alloy AGING Phase transformation
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Effect of Training on Two-way Shape Memory Effect and Its Stability in a Ti-Ni-Hf High Temperature Shape Memory Alloy 被引量:1
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作者 XianglongMENG WeiCAI +2 位作者 k.T.lau L.M.ZHOU LianchengZHAO 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第6期590-592,共3页
The Effect of the thermal cycling training under constant strain on the two-way shape memory effect (TWSME) in a Ti36l\li49Hf15 high temperature shape memory alloy (SMA) has been investigated by bending tests. The res... The Effect of the thermal cycling training under constant strain on the two-way shape memory effect (TWSME) in a Ti36l\li49Hf15 high temperature shape memory alloy (SMA) has been investigated by bending tests. The results indicated that the training procedure is beneficial to get the better TWSME. The two-way shape memory strain increases with increasing the training strain. And it decreases with increasing the training temperature. The TWSME obtained in the present alloy shows poorer stability compared with that obtained in the TiNi alloys. 展开更多
关键词 TiNiHf alloy High temperature shape memory alloy Two-way shape memory effect TRAINING
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High Hole Mobility of GaSb Relaxed Epilayer Grown on GaAs Substrate by MOCVD through Interfacial Misfit Dislocations Array
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作者 Wei Zhou Xiang Li +3 位作者 Sujing Xia Jie Yang Wu Tang k.M.lau 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2012年第2期132-136,共5页
The structural property of GaSb epilayers grown on semi-insulator GaAs (001) substrate by metalorganic chemical vapor deposition (MOCVD) using Triethylgallium (TEGa) and trimethylantimony (TMSb), was investiga... The structural property of GaSb epilayers grown on semi-insulator GaAs (001) substrate by metalorganic chemical vapor deposition (MOCVD) using Triethylgallium (TEGa) and trimethylantimony (TMSb), was investigated by variation of the Sb:Ga (V/Ill) ratio. An optimum V/Ill ratio of 1.4 was determined in our growth conditions. Using transmission electron microscopy (TEM), we found that there was an interracial misfit dislocations (IMF) growth mode in our experiment, in which the large misfit strain between epilayer and substrate is relaxed by periodic 90 deg. IMF array at the hetero-epitaxial interface. The rms roughness of a 300 nm-thick GaSb layer is only 2.7 nm in a 10μm×10μm scan from atomic force microscopy (AFM) result. The best hole density and mobility of 300 nm GaSb epilayer are 5.27xi06 cm-3(1.20×106) and 553 cm2-V-l.s-1 (2340) at RT (77 K) from Hall measurement, respectively. These results indicate that the IMF growth mode can be used in MOCVD epitaxial technology similar to molecular beam epitaxy (MBE) technology to produce the thinner GaSb layer with low density of dislocations and other defects on GaAs substrate for the application of devices. 展开更多
关键词 Interfacial misfit dislocations Metalorganic chemical vapour deposition Misfit dislocation Hole mobility
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ANOMALIES OF THE BACKGROUND CIRCULATION OF THE IAP GCM MODEL ATMOSPHERE IN AN EL NINO YEAR
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作者 王盘兴 k.M.lau S.H.Shen 《Acta meteorologica Sinica》 SCIE 1991年第5期608-,616,共2页
Analysis is performed of the May-September mean circulation,referred to as the background circulation hereinafter,in the IAP(Institute of Atmospheric Physics,Academia Sinica)GCM model atmosphere,It is found that in an... Analysis is performed of the May-September mean circulation,referred to as the background circulation hereinafter,in the IAP(Institute of Atmospheric Physics,Academia Sinica)GCM model atmosphere,It is found that in an El Nino year there occur anomalies in a set of major systems,e.g.,Southetm Oscillation,Walker and Hadley circulations,the western Pacific subtropical high and ITCZ,2nd in large-scale precipitation,with their happening dominantly in the Northern Hemisphere tropical and subtropical latitudes in the western Pacific. These results that are in rough agreement with the analyzd actual observations demonstrate the applicabilities of the model to the study of low-latitude circulations. 展开更多
关键词 GCM anomaly of atmospheric circulation El Nino event
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承压设备安全——来自加拿大阿尔伯达省的报告 赠给劳动部锅炉压力容器检测研究中心加拿大阿尔伯达省总检验师
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作者 k.T.lau 刘学玲 《中国锅炉压力容器安全》 1992年第2期51-51,55,共2页
在加拿大,承压设备的安全与一些其它特殊问题一样,通常由地方政府管理,而在铁路、海洋、航空运输和安装在联邦政府机构中的承压设备不属此例。铁路、海洋和航空运输中的承压设备由加拿大的运输部和危险品运输董事会管理,而安装在联邦政... 在加拿大,承压设备的安全与一些其它特殊问题一样,通常由地方政府管理,而在铁路、海洋、航空运输和安装在联邦政府机构中的承压设备不属此例。铁路、海洋和航空运输中的承压设备由加拿大的运输部和危险品运输董事会管理,而安装在联邦政府机构中的锅炉和压力容器则受联邦政府管理。不过在加拿大联邦政府和省及地方政府之间是有和约的,这些设备的检验要根据各个政府的法规由省及地方的检验员实施。由于承压设备的安全受省及地方的管辖,各省及地方部有锅炉和压力容器的立法。这些法通常是针对使用在该省或地区的承压设备的设计、制造和操作要求而制定的。 展开更多
关键词 承压设备 安全 压力容器 锅炉
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Light-absorbing Particles in Snow and Ice: Measurement and Modeling of Climatic and Hydrological impact 被引量:20
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作者 Yun QIAN Teppei J.YASUNARI +7 位作者 Sarah J.DOHERTY Mark G.FLANNER William k.M.lau MING Jing Hailong WANG Mo WANG Stephen G.WARREN Rudong ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第1期64-91,共28页
Light absorbing particles(LAP, e.g., black carbon, brown carbon, and dust) influence water and energy budgets of the atmosphere and snowpack in multiple ways. In addition to their effects associated with atmospheric... Light absorbing particles(LAP, e.g., black carbon, brown carbon, and dust) influence water and energy budgets of the atmosphere and snowpack in multiple ways. In addition to their effects associated with atmospheric heating by absorption of solar radiation and interactions with clouds, LAP in snow on land and ice can reduce the surface reflectance(a.k.a., surface darkening), which is likely to accelerate the snow aging process and further reduces snow albedo and increases the speed of snowpack melt. LAP in snow and ice(LAPSI) has been identified as one of major forcings affecting climate change, e.g.in the fourth and fifth assessment reports of IPCC. However, the uncertainty level in quantifying this effect remains very high. In this review paper, we document various technical methods of measuring LAPSI and review the progress made in measuring the LAPSI in Arctic, Tibetan Plateau and other mid-latitude regions. We also report the progress in modeling the mass concentrations, albedo reduction, radiative forcing, and climatic and hydrological impact of LAPSI at global and regional scales. Finally we identify some research needs for reducing the uncertainties in the impact of LAPSI on global and regional climate and the hydrological cycle. 展开更多
关键词 light-absorbing aerosol SNOW ice ALBEDO MEASUREMENT climate modeling hydrological cycle
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大气污染物监测数据不确定度评估方法体系建立及其对PMF源解析的影响分析 被引量:17
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作者 张夏夏 袁自冰 +4 位作者 郑君瑜 林小华 刘启汉 郁建珍 余立之 《环境科学学报》 CAS CSCD 北大核心 2019年第1期95-104,共10页
目前,正定矩阵因子法(PMF)在大气污染物来源解析中得到了广泛应用,而监测数据不确定度评估是PMF源解析的重要内容之一.当前绝大部分研究采用的数据不确定度仅通过借鉴前人的方法简单计算而得,缺乏对计算方法的合理性和适用性进行评估.... 目前,正定矩阵因子法(PMF)在大气污染物来源解析中得到了广泛应用,而监测数据不确定度评估是PMF源解析的重要内容之一.当前绝大部分研究采用的数据不确定度仅通过借鉴前人的方法简单计算而得,缺乏对计算方法的合理性和适用性进行评估.本研究通过3种常用的不确定度算法交互应用建立了一套有效评估不确定度的方法体系.通过对香港荃湾站点1998—2008年PM_(10)组分监测数据进行源解析并与平行采样数据源解析结果进行对比,对该方法体系的合理性进行了验证.结果发现,应用该方法体系可以将某些常规方法无法分离的因子进一步分解,得到的源解析结果的残差值甚至小于平行采样方法解析结果的残差值,得到的因子贡献率均处于常规方法得出的因子贡献率之间.这些均表明了该方法体系所得源解析结果的可靠性和全面性.因此,本研究建立的评估不确定度的方法体系具有较强的可行性,对确保源解析结果的准确性有重要意义. 展开更多
关键词 不确定度评估方法体系 源解析 正定矩阵因子法
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Application of MODIS satellite products to the air pollution research in Beijing 被引量:12
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作者 Alexis k.H.lau 《Science China Earth Sciences》 SCIE EI CAS 2005年第z2期209-219,共11页
The direct correlation between NASA MODIS aerosol optical depth (AOD) products and the air pollution index (API) in Beijing was found relatively low based on the long-term comparison analysis. The correlation improved... The direct correlation between NASA MODIS aerosol optical depth (AOD) products and the air pollution index (API) in Beijing was found relatively low based on the long-term comparison analysis. The correlation improved to some extent after taking account of the seasonal variation of scale height and the vertical distribution of aerosols. The correlation coefficient further improved significantly after considering the influencing factor of Relative Humidity (RH). This study concluded that satellite remote-sensing could serve as an efficient tool for monitoring the spatial distribution of particulate pollutants on the ground-level, as long as corrections have been made in the two aforementioned processes. Taking advantage of the MODIS information, we analyzed a pollution episode occurring in October 2004 in Beijing. It indicated that satellite remote-sensing could describe the formation process of the ground-level pollution episode in detail, and showed that regional transport and the topography were crucial factors to air quality in Beijing. The annual averaged distribution in the urban area of Beijing and its surroundings could be also obtained from the high-resolution retrieval results, implicating that high-resolution satellite remote-sensing might be potential in monitoring the source distribution of particulate pollutants. 展开更多
关键词 PARTICULATE pollution MODIS aerosol.
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A six-year descriptive epidemiological study of human coronavirus infections in hospitalized patients in Hong Kong 被引量:11
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作者 Cyril C.Y.Yip Carol S.F.Lam +8 位作者 Hayes k.H.Luk Emily Y.M.Wong Rodney A.Lee Lok-Yee So kwok-Hung Chan Vincent C.C.Cheng kwok-Yung Yuen Patrick C.Y.Woo Susanna k.P.lau 《Virologica Sinica》 SCIE CAS CSCD 2016年第1期41-48,共8页
We conducted a six-year epidemiological study on human coronaviruses(HCoVs) circulating in Hong Kong, using 8275 nasopharyngeal samples from patients with acute respiratory tract infections. HCoVs were detected in 7... We conducted a six-year epidemiological study on human coronaviruses(HCoVs) circulating in Hong Kong, using 8275 nasopharyngeal samples from patients with acute respiratory tract infections. HCoVs were detected in 77(0.93%) of the samples by a pan-HCoV RT-PCR assay. The most frequently detected HCoV species was HCoV-OC43(0.58%), followed by HCoV-229E(0.15%),HCoV-HKU1(0.13%) and HCoV-NL63(0.07%). HCoVs were detected throughout the study period(September 2008–August 2014), with the highest detection rate from September 2010 to August2011(22/1500, 1.47%). Different seasonal patterns of each HCoV species in Hong Kong were noted.HCoV-OC43 was predominant in the fall and winter, whereas HCoV-HKU1 showed peak activity in winter, with a few cases occurred in spring and summer. HCoV-229 E mainly occurred in winter and spring, while HCoV-NL63 was predominant in summer and autumn. HCoVs most commonly infect the elderly and young children, with median age of 79.5 years(range, 22 days to 95 years).Intriguingly, the detection rate of HCoV-OC43 in the age group of &gt; 80 years(26/2380, 1.09%) was significantly higher than that in the age group of 0–10 years(12/2529, 0.47%)(P 〈 0.05). These data provides new insight into the epidemiology of coronaviruses. 展开更多
关键词 epidemiology human coronaviruses respiratory tract infections
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Net effect of air pollution controls on health risk in the Beijing-Tianjin-Hebei region during the 2022 winter Olympics and Paralympics
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作者 Changqing Lin Peter k.k.Louie +7 位作者 Alexis k.H.lau Jimmy C.H.Fung Zibing Yuan Minghui Tao Xuguo Zhang Md.Shakhaoat Hossain Chengcai Li Xiang Qian Lao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第1期560-569,共10页
Due to the non-linearity in ozone(O_(3))formation,reducing the emission of nitrogen oxides(NO_(x))may increase O_(3) concentration.Given the counteractive O_(3) response to NO_(x) reduction,overall impact of air pollu... Due to the non-linearity in ozone(O_(3))formation,reducing the emission of nitrogen oxides(NO_(x))may increase O_(3) concentration.Given the counteractive O_(3) response to NO_(x) reduction,overall impact of air pollution controls can be ambiguous when the assessments focus on the changes in pollutant concentrations.In this study,a risk-based method was used to gauge the net effect of air pollution controls on mortality risk in the Beijing–Tianjin–Hebei(BTH)region during the 2022 Winter Olympics and Paralympics(WOP).This mega-event presents a unique opportunity to investigate the efficacy of deep cuts in pollutant emissions.Results show that O_(3) concentrations greatly increased as nitrogen dioxide(NO_(2))concentrations decreased in the BTH.Due to the active photochemical formations,O_(3) became the dominant pollutant that affected human health during the WOP.Despite the substantial O_(3) increases,the health benefits of NO_(2) reductions overwhelmed the adverse health effects of O_(3) increases in most regions of the BTH(at 81 out of 112 stations).After considering the impacts of particulate matter,the integrated health risk of air pollution mixtures declined almost everywhere in the BTH.Our results underscore the great necessity of changing the assessment paradigm of pollution control from using concentration-based methods to using risk-based methods.Together with the carbon neutrality policy,stringent control of NO_(x)emission from combustion sources is a promising way to achieve synergistic control solutions for air pollution and climate change. 展开更多
关键词 OZONE Nitrogen dioxide Health risk Carbon neutrality MEGA-EVENTS
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纳米二氧化硅填料量对LDPE复合材料局部放电特性的影响(英文) 被引量:6
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作者 Z.Abdul-Malek A.M.Azzin +3 位作者 Y.Z.Arief Aulia k.Y.lau M.Jaafar 《高电压技术》 EI CAS CSCD 北大核心 2011年第11期2629-2635,共7页
Partial discharges(PDs) due to artificial void in samples of LDPE nanocomposite sheet have been investigated in this work.PDs may cause the degradation of insulating materials and may affect the lifetime of high-volta... Partial discharges(PDs) due to artificial void in samples of LDPE nanocomposite sheet have been investigated in this work.PDs may cause the degradation of insulating materials and may affect the lifetime of high-voltage apparatus. An experimental work using sphere ball-plane electrode system(CIGRE MethodⅡ) and a 1.0 mm LDPE composite sheet was carried out.Different weight percentages of nanosilica(0%,2%,4%,6%and 8%) were used. PD experimental results,such as PD magnitude and PD number(both PD pulse polarities),as functions of the applied stress duration at a specified applied voltage were compared.The surface morphology of specimens was also presented and this conforms to the PD findings.The experimental results show that the PD characteristics of the LDPE generally improve with the introduction of nanosilica,the composite with the highest content of filler,namely the 8%(wt) nanosilica sample has the least partial discharge activities. 展开更多
关键词 LDPE NANOCOMPOSITE NANOSILICA partial discharges
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Two-dimensional gel electrophoresis in bacterial proteomics 被引量:5
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作者 Shirly O.T.Curreem Rory M.Watt +1 位作者 Susanna k.P.lau Patrick C.Y.Woo 《Protein & Cell》 SCIE CSCD 2012年第5期346-363,共18页
Two-dimensional gel electrophoresis(2-DE)is a gel-based technique widely used for analyzing the pro-tein composition of biological samples.It is capable of resolving complex mixtures containing more than a thousand pr... Two-dimensional gel electrophoresis(2-DE)is a gel-based technique widely used for analyzing the pro-tein composition of biological samples.It is capable of resolving complex mixtures containing more than a thousand protein components into individual protein spots through the coupling of two orthogonal bio-physical separation techniques:isoelectric focusing(first dimension)and polyacrylamide gel electrophore-sis(second dimension).2-DE is ideally suited for ana-lyzing the entire expressed protein complement of a bacterial cell:its proteome.Its relative simplicity and good reproducibility have led to 2-DE being widely used for exploring proteomics within a wide range of envi-ronmental and medically-relevant bacteria.Here we give a broad overview of the basic principles and his-torical development of gel-based proteomics,and how this powerful approach can be applied for studying bacterial biology and physiology.We highlight specific 2-DE applications that can be used to analyze when,where and how much proteins are expressed.The links between proteomics,genomics and mass spectrometry are discussed.We explore how proteomics involving tandem mass spectrometry can be used to analyze(post-translational)protein modifications or to identify proteins of unknown origin by de novo peptide se-quencing.The use of proteome fractionation tech-niques and non-gel-based proteomic approaches are also discussed.We highlight how the analysis of pro-teins secreted by bacterial cells(secretomes or exo-proteomes)can be used to study infection processes or the immune response.This review is aimed at non-specialists who wish to gain a concise,compre-hensive and contemporary overview of the nature and applications of bacterial proteomics. 展开更多
关键词 two-dimensional gel electrophoresis bacte-ria PROTEOMICS
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真丝绸服装的线迹和缝型的选择 被引量:2
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作者 k.P.lau H.Tam 马建兴 《江苏丝绸》 1995年第2期52-53,51,共3页
引言真丝,纤维中的皇后,历史悠久,其制品手感柔软,光泽优雅,为人们所青睐。为了成功地确定市场战略和满足顾客的要求,我们开发了众多重量和不同结构的真丝绸,薄的如薄纱、缎、双绉、绢丝纺、绵绸和府绸,厚的如传统山东绸和柞蚕丝织物。... 引言真丝,纤维中的皇后,历史悠久,其制品手感柔软,光泽优雅,为人们所青睐。为了成功地确定市场战略和满足顾客的要求,我们开发了众多重量和不同结构的真丝绸,薄的如薄纱、缎、双绉、绢丝纺、绵绸和府绸,厚的如传统山东绸和柞蚕丝织物。虽然提花丝织物为忠实的消费肯永久喜爱,但现代面料如皮革、麂皮及灯芯绒则对绸缎设计者提供了许多创新的启示。近年来,新的工艺技术已解决了一些丝绸服装加工中的传统问题。 展开更多
关键词 丝织物 服装 线迹 缝型 缝纫
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Next-Generation Sequencing-Based Diagnosis of Bacteremic Listeria monocytogenes Meningitis in a Patient with Anti-Interferon Gamma Autoantibodies:A Case Report
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作者 Fanfan Xing Derek L.L.Hung +3 位作者 Simon k.F.Lo Shuang Chen Susanna k.P.lau Patrick C.Y.Woo 《Infectious Microbes & Diseases》 2022年第1期44-46,共3页
Although various opportunistic infections have been described in patients with anti-interferon gamma autoantibodies,so far there is no Listeria monocytogenes infection reported to be associated with this primary immun... Although various opportunistic infections have been described in patients with anti-interferon gamma autoantibodies,so far there is no Listeria monocytogenes infection reported to be associated with this primary immunodeficiency.Here,we describe the first case of bacteremic L.monocytogenes meningitis in a 59-year-old Chinese man with anti-interferon gamma autoantibodies,who presented with acute onset of fever and severe headache.Blood culture was positive but culture of the cerebrospinal fluid was negative,although it showed features suggestive of partially treated bacterial meningitis.The presence of L.monocytogenes in the cerebrospinal fluid was confirmed by next-generation sequencing.Avoidance of high-risk food items in these patients is important for the prevention of listeriosis.The use of antibiotic regimens that cover Listeria is crucial for empirical treatment,particularly if such patients develop acute or subacute meningitis.Next-generation sequencing is becoming an important diagnostic modality for culture-negative infections. 展开更多
关键词 Listeria monocytogenes MENINGITIS anti-interferon gamma autoantibody next-generation sequencing
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Over-the-Air Aggregation for Federated Learning:Waveform Superposition and Prototype Validation 被引量:1
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作者 Huayan Guo Yifan Zhu +5 位作者 Haoyu Ma Vincent k.N.lau kaibin Huang Xiaofan Li Huabin Nong Mingyu Zhou 《Journal of Communications and Information Networks》 EI CSCD 2021年第4期429-442,共14页
In this paper,we develop an orthogonal frequency-division multiplexing(OFDM)-based over-theair(OTA)aggregation solution for wireless federated learning(FL).In particular,the local gradients in massive Internet of thin... In this paper,we develop an orthogonal frequency-division multiplexing(OFDM)-based over-theair(OTA)aggregation solution for wireless federated learning(FL).In particular,the local gradients in massive Internet of things(IoT)devices are modulated by an analog waveform and are then transmitted using the same wireless resources.To this end,achieving perfect waveform superposition is the key challenge,which is difficult due to the existence of frame timing offset(TO)and carrier frequency offset(CFO).In order to address these issues,we propose a two-stage waveform pre-equalization technique with a customized multiple access protocol that can estimate and then mitigate the TO and CFO for the OTA aggregation.Based on the proposed solution,we develop a hardware transceiver and application software to train a real-world FL task,which learns a deep neural network to predict the received signal strength with the global positioning system information.Experiments verify that the proposed OTA aggregation solution can achieve comparable performance to offline learning procedures with high prediction accuracy. 展开更多
关键词 over-the-air aggregation federated learning Internet of things
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Lorenz吸引子的微观结构 被引量:1
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作者 薛禹胜 Q.H.Wu +2 位作者 周海强 檀斌 k.W.lau 《非线性动力学学报》 2003年第1期1-12,共12页
轨迹保稳降维是一种分析高维非线性系统稳定性的方法。其要点是先在高维空问中求取轨迹;再将F轨迹映射为n-1个R^2映像,并在变换中严格保持感兴趣的稳定特性:分析各映像轨迹的稳定性:最后聚合为原轨迹特性的描述。本文按此分析Loren... 轨迹保稳降维是一种分析高维非线性系统稳定性的方法。其要点是先在高维空问中求取轨迹;再将F轨迹映射为n-1个R^2映像,并在变换中严格保持感兴趣的稳定特性:分析各映像轨迹的稳定性:最后聚合为原轨迹特性的描述。本文按此分析Lorenz吸引子的结构稳定性。例如,将其中的z变量处理为时变参量后,(x,y)子系统成为时变的线性2维系统,可得分岔集{zcr}及奇点特性沿z轴的变化规律。故对于特定的轨迹(x,y,z),可将其在各坐标平面上的投影轨迹分成短线段的有序队列,各相邻线段对应于特性不同的奇点,从而揭示Lorenz吸引子全局分岔的精细结构及其通往高维混沌的道路。 展开更多
关键词 Lorenz吸引子 微观结构 高维非线性系统 结构稳定性 轨迹保稳降维 混沌 全局分岔
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Severe Sepsis Caused by Listeria monocytogenes in A Patient Given Monoclonal Antibodies Against CD38 and Proteosome Inhibitor 被引量:1
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作者 Derek L.L.Hung Susanna k.P.lau Patrick C.Y.Woo 《Infectious Microbes & Diseases》 2019年第1期30-31,共2页
Introduction Target therapies are widely used for treatment of various kinds of hematological malignancies.Since the cancer cells that are targeted,share the same markers with the non-cancerous cells of the immunologi... Introduction Target therapies are widely used for treatment of various kinds of hematological malignancies.Since the cancer cells that are targeted,share the same markers with the non-cancerous cells of the immunological system,these therapies are often associated with infectious diseases that require the particular type of immune response for control.In this article,we report a case of Listeria monocytogenes bacteraemia complicating carfilzomib and daratumumab treatment for multiple myeloma.To the best of our knowledge,this is the first case report of listeriosis as a complication of monoclonal antibodies against CD38 and/or proteosome inhibitor therapy. 展开更多
关键词 LISTERIA multiple myeloma daratumumab carfilzomib
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