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物理学报 2005年第9期54卷 4416-4421页

作者：丁硕刘玉龙萧季驹中国科学院物理研究所北京100080 香港城市大学物理与材料科学系

对晶粒尺寸在4—80nm范围的纯SnO2纳米颗粒进行了拉曼散射研究.除了SnO2本征拉曼振动峰外,还有几个新的拉曼振动峰和波长在700nm左右的一个发光很强而且峰宽很大的荧光峰被观察到.结果所示,当纳米颗粒尺寸减小时,纳米SnO2颗粒的体相特... 详细信息

对晶粒尺寸在4—80nm范围的纯SnO2纳米颗粒进行了拉曼散射研究.除了SnO2本征拉曼振动峰外,还有几个新的拉曼振动峰和波长在700nm左右的一个发光很强而且峰宽很大的荧光峰被观察到.结果所示,当纳米颗粒尺寸减小时,纳米SnO2颗粒的体相特征拉曼峰变弱,而由缺陷,表面和颗粒尺寸引起的相关效应呈强势.晶粒尺寸在20nm左右是引起体相拉曼光谱变化的临界尺寸.晶粒尺寸在20nm以下,其体相拉曼峰的发生宽化和峰位移动,以及分别出现在位于571cm-1的表面振动峰,位于351cm-1处的界面峰和与表面吸附水分子及氢氧基团的N系列拉曼峰是纳米SnO颗粒的主要特征.这些结果反映了纳米颗粒的微结构变化与颗粒尺寸和表面效应以及它们之间相互作用的信息.

关键词：纳米SnO2 拉曼光谱荧光光谱水分子的吸附拉曼散射晶粒尺寸纳米粒子光谱研究纳米颗粒表面振动颗粒尺寸微结构变化

Prenatal diagnosis of choledochal cyst using magnetic resonance imaging: A case report

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World Journal of Gastroenterology 2005年第32期11卷 5082-5083页

作者： Alex Mun-Ching Wong yun-Chung Cheung yu-Hung Liu Koon-Kwan Ng siu-Cheung Chan Shu-Hang Ng Department of Diagnostic RadiologyChang Gung Memorial Hospital Kwei-ShanTao-YuanTaiwanChina Obstetrics and GynecologyChang Gung Memorial Hospital 222Mei Chin RoadKeelungTaiwanChina

Choledochal cysts are congenital anomalies of the biliary ducts, characterized by cystic dilatation of the *** diagnosis of this anomaly using ultrasonography (US) has been well documented. Magnetic resonance imaging (MRI) has recently become an important complement to US in prenatal diagnosis of fetal anomalies. We herein report a patient in whom at 24 wk' gestation US suggested a right upper quadrant abdominal cyst and in whom at 26 wk' gestation MRI more clearly delineated the cyst and its surrounding structures and suggested a choledochal cyst, which was confirmed at postnatal surgery and histopathology.

关键词： Choledochal cyst Prenatal diagnosis MRI

Hepatic venous outflow obstruction after piggyback liver transplantation by an unusual mechanism:Report of a case

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World Journal of Gastroenterology 2006年第33期12卷 5416-5418页

作者： Simon siu-Man Ng Simon Chun-Ho yu Janet Fung-Yee Lee Paul Bo-San Lai Wan-Yee Lau Departments of Surgery and Diagnostic Radiology & Organ Imaging Chinese University of Hong Kong Prince of Wales Hospital Shatin Hong Kong China

Hepatic venous outflow obstruction after piggyback liver transplantation is a very rare complication. An unusual mechanism aggravating it is reported. A 33-year-old man with end-stage hepatitis B liver cirrhosis underwent a piggyback orthotopic liver transplantation using a full-size cadaveric graft. Two months after transplantation, he developed gross ascites refractory to maximal diuretic therapy. Doppler ultrasound showed patent portal and hepatic veins. Serial computed tomography scans revealed a hypoperfused right posterior segment of the liver which subsequently underwent atrophy. Hepatic venography demonstrated a high-grade stenosis with an element of torsion of venous drainage at the anastomosis. The stenosis was successfully treated with repeated percutaneous balloon angioplasty. The patient remained asymptomatic six months afterwards with complete resolution of ascites and peripheral edema. We postulate that liver allograft segmental hypoperfusion and atrophy may aggravate or result in a hepatic venous outflow problem by the mechanism of torsion effect. Percutaneous balloon angioplasty is a safe and effective treatment modality for anastomotic stenosis.

关键词： Hepatic venous outflow obstruction Piggyback Liver transplantation Percutaneous balloon angioplasty

An AI-empowered indoor digital contact tracing system for COVID-19 outbreaks in residential care homes

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Infectious Disease Modelling 2024年第2期9卷 474-482页

作者： Jiahui Meng Justina Yat Wa Liu Lin Yang Man Sing Wong Hilda Tsang Boyu yu Jincheng yu Freddy Man-Hin Lam Daihai He Lei Yang Yan Li Gilman Kit-Hang siu Stefanos Tyrovolas Yao Jie Xie David Man David H.K.Shum School of Nursing The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Electronic and Information Engineering The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Research Centre of Textiles for Future Fashion The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Department of Applied Mathematics The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina The Jockey Club School of Public Health and Primary Care The Chinese University of Hong KongHong Kong Special Administrative RegionChina Department of Rehabilitation Sciences The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Department of Computing The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Department of Health Technology and Informatics The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina Department of Nutrition and Food Studies George Mason UniversityUSA Tung Wah College Hong Kong Special Administrative RegionChina Mental Health Research Centre The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina

An AI-empowered indoor digital contact-tracing system was developed using a centralized architecture and advanced low-energy Bluetooth technologies for indoor positioning,with careful preservation of privacy and data *** analyzed the contact pattern data from two RCHs and investigated a COVID-19 outbreak in one study *** evaluate the effectiveness of the system in containing outbreaks with minimal contacts under quarantine,a simulation study was conducted to compare the impact of different quarantine strategies on outbreak containment within *** significant difference in contact hours between weekdays and weekends was observed for some pairs of RCH residents and staff during the two-week data collection *** significant difference between secondary cases and uninfected contacts was observed in a COVID-19 outbreak in terms of their demographics and contact *** results based on the collected contact data indicated that a threshold of accumulative contact hours one or two days prior to diagnosis of the index case could dramatically increase the efficiency of outbreak containment within RCHs by targeted isolation of the close *** study demonstrated the feasibility and efficiency of employing an AI-empowered system in indoor digital contact tracing of outbreaks in RCHs in the post-pandemic era.

关键词： COVID-19 Indoor contact tracing Contact pattern Outbreak containment Artificial intelligence

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离心成型工艺与旋转震动现象

混凝土与水泥制品 2011年第7期 34-37页

作者：余兆炽

对照混凝土振动成型工艺,讨论了离心成型工艺的特点;分析了离心成型特有的旋转震动现象;探讨了以限制机具缺陷的程度来防止模具震动的可能性。

关键词：旋转震动离心力场离心加速度推动力矩偏心距椭圆度

Production of Hypoxia-induced Corneal Edema in Aged Eyes

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Eye Science 2004年第1期20卷 1-5页

作者： alan K. Cheung Andrew W. siu Digby W. Cheung Edwin C. Mo Department of Optometry & Radiography The Hong Kong Polytechnic University Kowloon Hong Kong SAR China.Department of Optometry & Radiography The Hong Kong Polytechnic University Kowloon Hong Kong SAR China.Department of Optometry & Radiography The Hong Kong Polytechnic University Kowloon Hong Kong SAR China.Department of Optometry & Radiography The Hong Kong Polytechnic University Kowloon Hong Kong SAR China.

Purpose:Corneal thickness assessment is a common clinical procedure applied in corneal and contact lens care. This study aims to investigate the effect of age on hypoxia-induced corneal ***:Eighteen male subjects were equally divided into the younger [(23.7 ± 0.8) years old] and older [(74.4 ± 2.5) years old] groups. Each subject wore a thick soft contact lens (uniform thickness of 0.3 mm) on the left cornea. With the contact lens in place, the baseline central corneal thickness was measured using a specially designed photo-pachometer. The lens was then patched behind the closed eyelids, producing an extremely hypoxic stress to the cornea. The change in central corneal thickness was monitored every 20 minutes with momentary disruptions to the hypoxic stress over the next 2 hours. The increase in thickness was taken as an index of corneal edema. The rate of change in corneal thickness, as derived from a non-linear mathematical model, was compared between ***:The corneal thickness of both age groups increased significantly with time (P<0.000 1). The mean corneal swelling constant for the older subjects was 16.5 × 10-3 (S.E.M. = 2.65 × 10-3) and the value for the younger subjects was 46.5 × 10-3 (S.E.M. = 3.25 × 10-3). The difference was statistically significant (P < 0.000 1).Conclusion:Aging cornea has a slower hypoxia-induced edema response compared with the younger group. Whether it is caused by a decreased corneal lactate production or an increased resistance to physical expansion deserves further investigation. Eye Science 2004;20:1-5.

关键词：低氧症角膜水肿眼科学老化角膜组织缺氧

Primary pneumothorax:Should surgery be offered after the first episode?

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World Journal of Respirology 2015年第1期5卷 47-57页

作者： alan DL Sihoe Peter SY yu Jerry WL Yeung Division of Cardiothoracic Surgery Department of SurgeryLi Ka Shing Faculty of Medicinethe University of Hong KongQueen Mary Hospital

Surgery is the recommended and most effective means of preventing the recurrence of primary spontaneous pneumothorax(PSP). However, the conventional belief amongst most clinicians is that surgery should not be routinely offered to patients with an uncomplicated first episode of PSP. The view that surgery should be reserved for recurrent episodes of ipsilateral PSP is based on an apprehension regarding traumatic thoracicsurgery combined with a perception that recurrences after a single episode of PSP are unlikely. Modern advances in minimally invasive thoracic surgery have now dramatically reduced the morbidity of PSP surgery. Such surgery is now safe, effective and causes minimal indisposition for patients. On the other hand, modern clinical data suggests that recurrence rate of PSP is perhaps much higher than previously assumed, with more than half of patients experiencing a second episode within several years of the first. With such new appreciations of the current situation, it is appropriate to now consider offering surgery to patients even after the first episode of PSP.

关键词： Health economics Health policy Outcomes Pleural space(drainage,management) Pleurodesis Pneumothorax Surgery Thoracoscopy Video-assisted thoracic surgery

Synthesis, Structure and Non-linear Optical Properties of Manganese Mercury Tetrathiocyanate

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Chinese Chemical Letters 1999年第3期10卷 257-260页

作者： yun Xing YAN Qi FANG Duo Rong yuAN yu Peng TIAN Zhi LIU Xiao MeiWANG Min Hua JIANG D. WILLIAMS A. siu Zhi Gang CAI (Institute of Crystal Materials and State Key Laboratory of Crystal Materials,Shandong University. Jinan 250100)(Department of Chem Shandong Univ Inst Crystal Mat Jinan 250100 Peoples R China Shandong Univ State Key Lab Crystal Mat Jinan 250100 Peoples R China Hong Kong Univ Sci & Technol Dept Chem Hong Kong Peoples R China Zhongshan Univ Inst Laser Spect Guangzhou 510275 Peoples R China Zhongshan Univ State Key Lab Ultrafast Lase Spect Guangzhou 510275 Peoples R China

The title copound Manganese Mercury Tetrathiocyanate (MnHg (SCN)(4)) has been synthesized and its structure has been determined. It belongs to tetragonal system, I (4) over bar space group. The cell dimensions are: a = 1.1324 (3) nm, c = 0.4270 (2) nm, V = 0.5475 (3) nm(3), Z = 2, D-c = 2.959 g/cm(3), R = 0.028, R-w = 0.037. The structure feature of the crystal is the Hg-S-C=N-Mn bridge which leads to the formation of an infinite three dimensional network. Irradiated by a 1064 nm Nd:YAG laser beam, MnHg (SCN), shows a 532 nm second harmonic intensity which is 18 times as that of organic nonlinear optical crystal urea, and therefore shows a quite promising application value as a useful nonliear optical material.

关键词： MnHg (SCN)(4) synthesis structure nonlinear optical property

传承或是生活方式引领者:伦敦当代城市环境中的疗愈空间研究

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景观设计学（中英文） 2016年第4期4卷 20-41页

作者：薛菲刘少瑜香港大学建筑学院新加坡国立大学设计与环境学院

以往的研究表明,城市绿地对人类健康具有促进疗愈和恢复的积极作用。传承了有益于人类健康和宜居性的城镇与乡村相结合的后花园城市—伦敦已成为世界上最绿色的城市之一,公园绿地也已深深融入伦敦市民的日常生活之中。本文作者对伦敦中... 详细信息

以往的研究表明,城市绿地对人类健康具有促进疗愈和恢复的积极作用。传承了有益于人类健康和宜居性的城镇与乡村相结合的后花园城市—伦敦已成为世界上最绿色的城市之一,公园绿地也已深深融入伦敦市民的日常生活之中。本文作者对伦敦中心城区及郊区进行了实证型研究,通过客观评估和主观调查,就建成环境品质、使用者态度和疗愈感知进行了研究。本文尤其关注疗愈感知的感官层面,旨在重新解读当代背景下疗愈空间的转变,并探究疗愈绩效提升的关键标准。最后,本文提出一个概念化的框架,以提升城市绿地设计的疗愈功效。

关键词：健康宜居性疗愈空间感知伦敦