检索结果-南通市图书馆

Majorana fermions in semiconducting nanowire and Fulde–Ferrell superconductor hybrid structures

Frontiers of physics 2019年第1期14卷 147-154页

作者： Jia Liu chun fai chan Ming Gong Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials and School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China Department of Physics and Center of Coherence The Chinese University of Hong Kong Shatin N. T. Hong Kong China Key Laboratory of Quantum Information University of Science and Technology of China Hefei 230026 China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials and School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China

The novel idea that spin-orbit coupling (SOC) and an s-wave pairing system can lead to induced pwave pairing with a strong magnetic limit, has stimulated widespread interest in searching for Majorana fermions (MFs) in semiconductor-superconductor hybrid structures. However, despite major advances in the semiconductor nanotechnology, this system has several inherent limitations that prohibit the realization and identification of MFs. We overcome these limitations by replacing the s-wave superconductor with the type-II Fulde-Ferrell (FF) superconductor, in which the center-of-mass momentum of the Cooper pair renormalizes the in-plane Zeeman field and chemical potential. As a result, MFs can be realized in semiconductor nanowires with small values of the Landé g-factor and high carrier densities. The SOC strength directly influences the topological boundary;thus, the topological phase transition and associated MFs can be engineered by an external electric field. Theoretically, almost all semiconductor nanowires can be used to realize MFs by using the FF superconductor. However, we find that InP nanowire is more suitable for the realization of MFs compared to InAs and InSb nanowires. Thus, this new scheme can take full advantage of the semiconductor nanotechnology for the realization of MFs in semiconductor-superconductor hybrid structures.

关键词： Majorana fermion topological transition Pfaffian FF-superconductor hybrid structure

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare case of intussusception in an adult with acute myeloid leukemia

引用

World Journal of Gastroenterology 2015年第2期21卷 688-693页

作者： Man fai Law Cheuk Kei Wong chun Yin Pang Hay Nun chan Ho Kei Lai chung Yin Ha Celia Ng Yiu Ming Yeung Sze fai Yip Department of Medicine Tuen Mun Hospital Department of Medicine and Therapeutics Prince of Wales Hospital Department of Radiology Kwong Wah Hospital Department of Pathology Tuen Mun Hospital

Intussusception is rarely reported in adult patients with acute leukemia. We report a case of intussusception in a 29-year-old woman with acute myeloid leukemia(AML). She developed right lower quadrant pain, fever, and vomiting on day 16 of induction *** examination showed tenderness and guarding at the right lower quadrant of the abdomen. Abdominal computed tomography(CT) showed distension of the cecum and ascending colon, which were filled with loops of small bowel, and herniation of the ileocecal valve into the cecum. We proceeded to laparotomy and revealed ileocecal intussusception with the ileocecal valve as the leading point. The terminal ileum was thickened and invaginated into the cecum, which showed gangrenous changes. Right hemicolectomy was performed and microscopic examination of the colonic tissue showed infiltration of leukemic cells. The patient recovered after the operation and was subsequently able to continue treatment for AML. This case demonstrates that the diagnosis of intussusception is difficult because the presenting symptoms can be non-specific, but abdominal CT can be informative for preoperative diagnosis. Resection of the involved bowel is recommended when malignancy is suspected or confirmed. Intussusception should be considered in any leukemia patients presenting with acute abdomen. A high index of clinical suspicion is important for early diagnosis.

关键词： Intussusception Acute leukemia Abdominal pain Colo

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Modelling smear effect of vertical drains using a diameter reduction method

引用

Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 279-290页

作者： Zhichao Shen Siau Chen Chian Siew Ann Tan chun fai Leung School of Marine Science and Engineering South China University of TechnologyGuangzhouChina Department of Civil and Environmental Engineering National University of SingaporeSingapore

Vertical drains are used to accelerate consolidation of clays in ground improvement *** zones exist around these drains,where permeability is reduced due to soil disturbance caused by the installation *** solution is widely used in practice to consider the effects of drain discharge capacity and smear on the consolidation *** this study,a computationally efficient diameter reduction method(DRM)obtained from the Hansbo solution is proposed to consider the smear effect without the need to model the smear zone *** by analytical and numerical results,a diameter reduction factor is analytically derived to reduce the diameter of the drain,while achieving similar solutions of pore pressure dissipation profile as the classical full model of the smear zone and *** the DRM,the excess pore pressure u obtained from the reduced drain in the original un-disturbed soil zone is accurate enough for practical applications in numerical *** performance of DRM is independent of soil material *** also show equally accurate performance of DRM under conditions of multi-layered soils and coupled radial-vertical groundwater flow.

关键词： Consolidation Vertical drain Smear effect Pore pressure Soil improvement

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Centrifuge study on behavior of raft foundation after tunnelling in soft clay

引用

Underground Space 2024年第4期17卷 161-169页

作者： Jian Yu Jiaming Liu chun fai Leung Maosong Huang Qi Wen Jorgin Tan Department of Geotechnical Engineering Key Laboratory of Geotechnical and Underground Engineering of Ministry of EducationTongji UniversityShanghai 200092China Centre for Offshore Research and Engineering Department of Civil and Environmental EngineeringNational University of Singapore119077Singapore Land Transport Authority 219428Singapore

Ground losses due to tunneling would induce settlement of nearby raft *** study the change in behavior of the raft foundations over time due to tunnel excavation in soft clay,a series of centrifuge model tests were *** results reveal that the raft stiffness has a significant influence on the development of the gap between the raft and the *** width of the gap beneath the flexible foundation would increase over time,leading to a further increase in tensile strain after excavation,whereas the gap for raft foundations with a large stiffness would reduce with time,causing a gradual decrease in tensile *** modification factor(MF)design approach is also evaluated with the test results and demonstrates that the MF design approach would underestimate the tensile strain of the flexible raft and provide a relatively conservative prediction for larger stiffnesses.

关键词： Tunnelling Raft Clay Deflection ratio Centrifuge test

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Modulation of morphological changes of microglia and neuroprotection by monocyte chemoattractant protein-1 in experimental glaucoma

引用

Cellular & Molecular Immunology 2010年第1期7卷 61-68页

作者： Kin Chiu Sze-chun Yeung Kwok-fai So Raymond Chuen-chung chang Laboratory of Neurodegenerative Diseases Department of AnatomyUniversity of Hong KongPokfulamHong KongChina State Key Laboratory of Brain and Cognitive Sciences University of HongKongPokfulamHongKongChina Research Centre of Heart BrainHormone and Healthy AgingLiKa Shing Faculty of MedicineUniversity of Hong KongPokfulamHong KongChina

Monocyte chemoattractant protein-1(MCP-1)/CCL2 is a C–C chemokine involved in the activation and recruitment of monocytic cells to injury ***-1/CCL2 can induce either neuroprotection or neurodestruction in vitro,depending on the experimental *** aim to use MCP-1/CCL2 as an experimental tool to investigate the morphological changes of microglia when loss of healthy retinal ganglion cells(RGCs)is exacerbated or attenuated in an experimental glaucoma *** a high concentration(1000 ng)of MCP-1/CCL2 and lipopolysaccharide(LPS)-exacerbated RGC loss,100 ng MCP-1/CCL2 provided neuroprotection towards *** MCP-1/CCL2(100 ng)also upregulated insulin-like growth factor-1(IGF-1)immunoreactivity in the *** neuroprotective effect of MCP-1/CCL2 was not due to the massiveinfiltration of microglia/*** together,this is the first report showing that an appropriate amount of MCP-1/CCL2 can protect RGCs in experimental glaucoma.

关键词： glaucoma IGF-1 MCP-1/CCL2 microglia neuroprotection

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Characterizing ionic species in PM_(2.5) and PM_(10) in four Pearl River Delta cities,South China

引用

Journal of Environmental Sciences 2007年第8期19卷 939-947页

作者： LAI Sen-chao ZOU Shi-chun CAO Jun-ji LEE Shun-cheng HO Kin-fai School of Chemistry and Chemical Engineering Sun Yat-sen University Guangzhou 510275 China. Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇ an 710075 China

PM2.5 and PM10 samples were collected at four major cities in the Pearl River Delta （PRD）, South China, during winter and summer in 2002. Six water-soluble ions, Na^＋, NH4＋, K^＋, Cl^-, NO3^- and SO4^2- were measured using ion chromatography. On average, ionic species accounted for 53.3% and 40.5% for PM2.5 and PM10, respectively in winter and 39.4% and 35.2%, respectively in summer. Secondary ions such as sulfate, nitrate and ammonium accounted for the major part of the total ionic species. Sulfate was the most abundant species followed by nitrate. Overall, a regional pollution tendency was shown that there were higher concentrations of sulfate, nitrate and ammonium in Guangzhou City than those in the other PRD cities. Significant seasonal variations were also observed with higher levels of species in winter but lower in summer. The Asian monsoon system was favorable for removal and diffusion of air pollutants in PRD in summer while highly loading of local industrial emissions tended to deteriorate the air quality as well. NO3^-/SO4^2- ratio indicated that mobile sources have considerably contribution to the urban aerosol, and stationary sources should not be neglected. Besides the primary emissions, complex atmospheric reactions under favorable weather conditions should be paid more attention for the control of primary emission in the PRD region.

关键词： water-soluble ions seasonal and spatial variations Pearl River Delta

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An Investigation of Effect of Stand-Off Distance on the Material Removal Characteristics and Surface Generation in Fluid Jet Polishing

引用

Nanomanufacturing and Metrology 2020年第2期3卷 112-122页

作者： chun Jin Wang Chi fai Cheung Lai Ting Ho Yee Man Loh State Key Laboratory of Ultra-precision Machining Technology Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

Fluid jet polishing(FJP)is a versatile polishing process that has many advantages compared to other polishing ***-off distance(SOD)is one of the key parameters in flu id jet polishi ***,relatively little research work has been carried out to investigate its effect of SOD on material removal characteristics and surface generation in *** this paper,a systematic investigation of the effect of SOD on the tool influence function and surface topography in FJP was *** were designed for FJP two kinds of materials corresponding to ductile and brittle *** are nickel copper(NiCu)alloy and BK7 optical glass,*** this study,the SOD was varied from 2 to 35 *** and discussions were made on its effect on the shape of TIF,material removal rate,and surface *** is interesting to note that the TIF shape becomes a Gaussian-like shape with large SOD both on NiCu and BK7,which provides a novel way to optimize the TIF in *** variation of the material removal rate and surface roughness versus SOD on NiCu and BK7 were also determined from the experimental ***,the surface topography of NiCu and BK7 were characterized from the results measured from the white light interferometer and scan electron *** outcome of the study provides a better understanding of the material removal characteristics and surface generation mechanism in FJP.

关键词： Fluid jet polishing Material removal characteristics Stand-off distance Tool influence function Surface generation Ultra-precision machining

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A prospective cohort of men with localized prostate cancer on active surveillance protocol in Hong Kong,China:what did we learn?

引用

Asian Journal of Andrology 2024年第3期26卷 245-249页

作者： Xiaobo Wu Ivan Ching-Ho Ko Cindy Yeuk-Lam Hong Samuel Chi-Hang Yee Jeremy Yuen-chun Teoh Samson Yun-Sang chan Ho-Man Tam Chi-Kwok chan Chi-fai Ng Peter Ka-Fung Chiu SH Ho Urology Centre Department of SurgeryFaculty of MedicineThe Chinese University of Hong KongHong KongChina

This study aimed to report the outcomes of active surveillance(AS)in the management of low-risk prostate cancer(PCa).It recruited87 men who were prospectively followed up according to the Prostate Cancer Research International Active Surveillance(PRIAS)protocol with local adaptation at SH Ho Urology Centre,Prince of Wales Hospital,Hong Kong,*** investigated the predictorsof disease progression and found that baseline prostate-specific antigen density(PSAD)and the presence of the highest ProstateImaging-Reporting and Data System(PI-RADS)score 5 lesion on magnetic resonance imaging(MRI)are significantly correlatedwith disease ***,men with PSAD>0.2 ng ml^(−2)or PI-RADS 4 or 5 lesions had significantly worse upgradingfree survival compared to those with PSAD≤0.2 ng ml−2 and PI-RADS 2 or 3 *** study concludes that AS is a safe andeffective management strategy for selected patients to defer radical treatment and that most disease progression can be detectedafter the first repeated *** combination of PSAD>0.2 ng ml^(−2)and PI-RADS 4 or 5 lesions may serve as a useful predictorof early disease progression and provide a guide to optimize follow-up protocols for men in different risk groups.

关键词： active surveillance cohort localized prostate cancer

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transurethral resection of prostate for acute urinary retention is linked to shorter survival in younger men

引用

Asian Journal of Andrology 2019年第5期21卷 468-472页

作者： Jeremy Yuen-chun Teoh Chi-Kwok chan Maggie Haitian Wang Chi-Ho Leung Eddie Shu-Yin chan Peter Ka-Fung Chiu Chi-Hang Yee Hon-Ming Wong Simon See-Ming Hou Chi-fai Ng S.H.Ho Urology Centre Department of SurgeryPrince of Wales HospitalThe Chinese University of Hong KongHong KongChina Division of Biostatistics JC School of Public Health and Primary CareThe Chinese University of Hong KongHong KongChina Division of Urology Department of SurgeryNorth District HospitalHong KongChina Division of Urology Department of SurgeryAlice Ho Miu Ling Nethersole HospitalHong KongChina

It is largely unknown whether lower urinary tract symptoms(LUTS)or acute retention of urine(AROU)is linked to shorter life expectancy in *** conducted a multicenter,retrospective database analysis of patients undergoing transurethral resection of prostate(TURP)to study their *** Cox regression analysis and Kaplan-Meier analysis with stratification to age and indication of TURP were *** further performed an age-and sex-matched survival analysis with the general population using data from the Census and Statistics Department of the Hong Kong Special Administrative Region(Hong Kong,China).From January 2002 to December 2012,3496 patients undergoing TURP were included in our study,with 1764 patients in the LUTS group and 1732 patients in the AROU *** age,ischemic heart disease,cerebrovascular accident,and AROU were risk factors of *** aged80 *** to the general population,younger patients in the LUTS group appeared to have better survival(80 years,survival was similar with the general population in both the LUTS and AROU *** conclusion,AROU at young age was associated with mortality,while early detection and management of LUTS may improve survival.

关键词： acute retention of urine lower urinary tract symptoms mortality transurethral resection of prostate

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Human embryonic stem cells as an in vitro model for studying developmental origins of type 2 diabetes

引用

World Journal of Stem Cells 2020年第8期12卷 761-775页

作者： Andy chun-Hang Chen Kai fai Lee William Shu Biu Yeung Yin Lau Lee Department of Obstetrics and Gynaecology The University of Hong KongHong KongChina Shenzhen Key Laboratory of Fertility Regulation The University of Hong Kong Shenzhen HospitalShenzhen 518053Guangdong ProvinceChina

The developmental origins of health and diseases(DOHaD)is a concept stating that adverse intrauterine environments contribute to the health risks of *** the theory emerged more than 30 years ago,many epidemiological and animal studies have confirmed that in utero exposure to environmental insults,including hyperglycemia and chemicals,increased the risk of developing noncommunicable diseases(NCDs).These NCDs include metabolic syndrome,type 2 diabetes,and complications such as diabetic *** the effects of different environmental insults on early embryo development would aid in understanding the underlying mechanisms by which these insults promote NCD *** stem cells(ESCs)have also been utilized by researchers to study the *** have pluripotent characteristics and can be differentiated into almost every cell lineage;therefore,they are excellent in vitro models for studying early developmental *** importantly,human ESCs(hESCs)are the best alternative to human embryos for research because of ethical *** this review,we will discuss different maternal conditions associated with DOHaD,focusing on the complications of maternal ***,we will review the differentiation protocols developed to generate different cell lineages from ***,we will review how hESCs are utilized as a model for research into the *** effects of environmental insults on hESC differentiation and the possible involvement of epigenetic regulation will be discussed.

关键词： Development origins of health and diseases Maternal diabetes Environmental insults Type 2 diabetes Human embryonic stem cells Epigenetics

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：