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Electromagnetic wave propagation of wireless capsule endoscopy in human body

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Journal of Central South University 2013年第10期20卷 2650-2656页

作者： LIM Eng-Gee 王炤陈瑾慧 TILLO Tammam MAN ka-lok Department of Electronic and Electrical Engineering Xi’an Jiaotong-Liverpool University

Wireless capsule endoscopy(WCE) is a promising technique which has overcome some limitations of traditional diagnosing tools, such as the comfortlessness of the cables and the inability of examining small intestine section. However, this technique is still far from mature and asks for the feasible improvements. For example, the relatively low transmission data rate and the absence of the real-time localization information of the capsule are all important issues. The studies of them rely on the understanding of the electromagnetic wave propagation in human body. Investigation of performance of WCE communication system was carried out by studying electromagnetic(EM) wave propagation of the wireless capsule endoscopy transmission channel. Starting with a pair of antennas working in a human body mimic environment, the signal transmissions and attenuations were examined. The relationship between the signal attenuation and the capsule(transmitter) position, and direction was also evaluated. These results provide important information for real-time localization of the capsule. Moreover, the pair of antennas and the human body were treated as a transmission channel, on which the binary amplitude shift keying(BASK) modulation scheme was used. The relationship between the modulation scheme, data rate and bit error rate was also determined in the case of BASK. With the obtained studies, it make possible to provide valuable information for further studies on the selection of the modulation scheme and the real-time localization of the capsules.

关键词： wireless capsule electromagnetic wave propagation transmission channel

Does the Belt and Road Initiative Promote Bilateral Political Relations?

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China & World Economy 2021年第5期29卷 57-83页

作者： Yue Lu Wei Gu ka Zeng School of International Trade and Economics University of International Business and Economics(UIBE)China Department of Economics The Chinese University of Hong KongChina Department of Political Science University of ArkansasUSA

This paper examines the role of the Belt and Road Initiative (BRI) in enhancing political relations between China and its partner countries. We postulate that an international economic cooperation scheme such as the BRI may facilitate commercial exchanges and increase the participating countries’ economic gains. This should generate incentives for these countries to avoid political tensions that may jeopardize mutually beneficial economic exchanges, and to expand the constellation of domestic coalitions in support of cordial diplomatic and political relations. We test the effect of the BRI on bilateral political relations using data on political relations between China and 91 countries along the BRI route between 2006 and 2018. Treating the promulgation of the BRI in 2013 as a policy shock, our difference-in-difference analysis lends substantial support to our hypotheses. Further analyses of the underlying causal mechanisms suggest that the BRI bolsters political relations by strengthening economic ties with partner countries through trade and investment related to economic cooperation.

关键词： BRI international economic cooperation political relations

Walking pace and the risk of stroke:A meta-analysis of prospective cohort studies

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Journal of Sport and Health Science 2020年第6期9卷 521-529页

作者： Minghui Quan Pengcheng Xun Ru Wang ka He Peijie Chen School of Kinesiology Shanghai University of SportShanghai 200438China Department of Epidemiology and Biostatistics School of Health-BloomingtonIndiana UniversityBloomingtonIN 47405USA

Purpose:The extent to which walking pace is associated with a reduced risk for stroke remains *** study examined the association between walking pace and stroke risk based on prospective cohort ***:Databases of PubMed,EMBASE,Web of Science,Scopus,and China National Knowledge Internet were searched from the inception dates to January 31,2019,for prospective cohort studies focusing on walking pace and risk of stroke in *** reviewers independently extracted data and assessed the quality of the *** dependent measure was stroke *** random-effects models,a metaanalysis was performed to estimate the overall relative risks(RR)of stroke incidence and 95%confidence intervals(CIs)for the individuals with the fastest walking paces *** with the slowest walking paces.A dose-response relationship was also ***:After screening 1294 titles/abstracts and 14 full-text studies identified in the search,7 studies(from 8 cohorts)were included in the *** 7 studies included a total of 135,645 participants(95.2%women;mean age 63.6 years)and 2229 stroke events(median follow-up time=8.0 years).Compared to individuals in the slowest walking-pace category(median=1.6 km/h),individuals in the fastest walking-pace category(median=5.6 km/h)had a 44%lower risk of stroke(pooled RR=0.56,95%CI:0.48-0.65).There was also a linear dose-response relationship(RR=0.87;95%CI:0.83-0.91),with the risk of stroke decreased by 13%for every 1 km/h increment in baseline walking *** observed similar results across walking-pace assessment,type of stroke ascertainment,stroke subtypes,sex,sample size,and duration of ***:Findings from this meta-analysis indicate that walking pace is inversely associated with the risk of stroke.

关键词： Dose response Meta-analytic review Stroke incidence Walking pace

Modulation doping of p-type Cu_(12)Sb_(4)S_(13)toward improving thermoelectric performance

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Journal of Materials Science & Technology 2024年第4期171卷 71-79页

作者： Khak Ho Lim Mingquan Li Yu Zhang Yue Wu Qimin Zhou Qingyue Wang Xuan Yang Pingwei Liu Wen-Jun Wang ka Wai Wong ka Ming Ng Yu Liu Andreu Cabot Institute of Zhejiang University-Quzhou Quzhou 324000China College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310007China School of Chemistry and Chemical Engineering Hefei University of TechnologyHefei 230009China Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA Ostia Technologies Limited United Kingdom Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayHong KongChina ICREA Pg.Lluis Companys 23Barcelona 08010Spain Catalonia Energy Research Institute-IREC Sant Adria del BesosBarcelona 08930Spain

The commercial viability of thermoelectric(TE)devices relies heavily on two factors:cost reduction and efficiency *** this study,we first produce p-type Cu_(12)Sb_(4)S_(16-x)(x=0,3,4)using a low-temperature bottom-up approach and demonstrate Cu_(12)Sb_(4)S_(13)to show the best TE performance among the three tested ***,the TE energy conversion efficiency of Cu_(12)Sb_(4)S_(13)is further enhanced by optimizing its electronic band structure through the incorporation of small amounts of *** an optimal Te content of 5 mol%,more than a twofold increase in the TE figure of merit(zT)is *** gain insight into the mechanism of improvement on the transport properties of the mate-rial,we compare the interphase transport mechanism by incorporating nanodomains of different metals(Ag and Cu)into the Cu_(12)Sb_(4)S_(13)*** improved electrical conductivity obtained with Cu_(12)Sb_(4)S_(13)-Te nanocomposites is attributed to a charge flooding of the Cu_(12)Sb_(4)S_(13)*** contrast,excessive down-ward band-bending at the interphases of Ag/Cu metal-semiconductor drastically reduces the electrical ***,a weighted mobility(μw)analysis shows a dominant thermal activation of carri-ers in Cu_(12)Sb_(4)S_(13)-Te *** this material,a strong decrease in lattice thermal conductivity is also found,which is associated with a phonon-carrier scattering *** work shows the impor-tance of proper band-engineering in TE nanocomposites to decouple electrical and thermal transport to enhance TE performance,and the efficacy ofμw for electrical and thermal transport analysis.

关键词： Modulation doping Thermoelectric Interphase transport Charge flooding Phonon-carrier scattering

The Study of Influence of Product Negative Review on Online Purchase Intention

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The Study of Influence of Product Negative Review on Online ...

作者： Eli（?）ka Hallová 浙江工商大学

学位级别：硕士

In recent years online shopping has become an integral part of our *** Covid-19 pandemic has only accelerated the entire transition from offline to online ***,the online sector has certain specifics and this is the fact that the online space gives customers the opportunity to express their negative information quickly and,above all,anonymously,and they have the opportunity to reaches a large number of people and is easier to *** addition,there is still a lack of confidence in online shopping in the Czech Republic as a ***,business owners must learn to work and analyse negative information as quickly as possible to eliminate the impact on their *** for this reason,the purpose of this work is to examine the influence of product negative information and its impact on the purchase intention in the Czech Republic in online *** study is based on conceptual study which works with five variables-Depth,Language style,Consistency,Source and Volume of negative information.A questionnaire using a Likert scale of1 to 5 was used to collect quantitative *** software was used for data *** results of the survey showed that all variables have a correlation effect on risk and intention to purchase,except gender does not play a role in perceiving risk in our *** study is considered beneficial to allow businesses in the market to see negative information,analysing them and to help them continue to work with them and protect their business.

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Characterization of available automated external def ibrillators in the market based on the product manuals in 2014

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World Journal of Emergency Medicine 2016年第2期7卷 138-146页

作者： Chik Leung Ho ka Wai Cheng Tze Hang Ma Yau Hang Wong ka Lok Cheng Chak Wah kam Department of Accident and Emergency Medicine Tuen Mun Hospital

BACKGROUND: To popularize the wide-spread use of automated external defi brillator(AED) to save life in sudden cardiac arrest, we compared the strength and weakness of different types of AEDs to enable a sound selection based on regional ***: This was a retrospective descriptive study. Different types of AEDs were compared according to the information of AEDs from manuals and brochures provided by the manufacturers. Fifteen types of AEDs were divided into 3 groups, basic, intermediate and ***: Lifeline? AUTO AED had the best performance in price, portability and user-friendly among AEDs of basic level. It required less time for shock charging. Samaritan PAD defi brillator was superior in price, portability, durability and characteristic among AEDs of intermediate level. It had the longest warranty and highest protection against water and dust. Lifeline? PRO AED had the best performance in most of the criteria among AEDs of advanced level and offered CPR video and manual mode for laypersons and clinicians ***: Lifeline? AUTO AED, Samaritan PAD def ibrillator, Lifeline? PRO AED are superior in AEDs of basic, intermediate and advanced levels, respectively. A feasible AED may be chosen by users according to the regional requirement and the current information about the best available products.

关键词： Automated external defi brillator Electrodes Pads Cardiac arrest

Carvedilol Versus Other Nonselective Beta Blockers for Variceal Bleeding Prophylaxis and Death: A Network Meta-analysis

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Journal of Clinical and Translational Hepatology 2023年第5期11卷 1143-1149页

作者： ka-Shing Cheung Chiu-Hang Mok Lok-ka Lam Xian-Hua Mao Lung-Yi Mak Wai-kay Seto Man-Fung Yuen Department of Medicine School of Clinical MedicineThe University of Hong KongQueen Mary HospitalHong KongChina Department of Medicine The University of Hong Kong-Shenzhen HospitalShenzhenGuangdongChina School of Clinical Medicine The University of Hong KongHong KongChina State Key Laboratory of Liver Research The University of Hong KongHong KongChina

Background and Aims:We aimed to perform a network meta-analysis(NWM)to examine comparative effectiveness of non-selective beta blockers(NSBBs)on prophylaxis of gastroesophageal variceal bleeding(GVB)and mortality ***:MEDLINE(OVID)and EMBASE databases were searched for eligible randomized clinical trials(RCTs)from inception to July 3,*** of interest included primary/secondary prophylaxis of GVB,failure to achieve hepatic venous pressure gradient(HVPG)decremental response,liver-related and all-cause mortality.A Bayesian NWM was performed to derive relative risk(RR)with 95%credible intervals(CrIs).The ranking probability of each NSBB was assessed by surface under cumulative ranking curve(SUCRA).Results:Thirty-three RCTs including 3,188 cirrhosis patients with gastroesophageal varices were *** with placebo,nadolol ranked first for reducing variceal bleeding[RR:0.25,(95%CrI:0.11–0.51);SUCRA:0.898],followed by carvedilol[RR:0.33,(95%CrI:0.11–0.88);SUCRA:0.692]and propranolol[RR:0.52,(95%CrI:0.37–0.75);SUCRA:0.405].Carvedilol was more effective than propranolol in achieving HVPG decremental response[RR:0.43,(95%CrI:0.26–0.69)].Carvedilol ranked first for reducing all-cause mortality[RR:0.32,(95%CrI:0.17–0.57);SUCRA:0.963],followed by nadolol[RR:0.48,(95%CI:0.29–0.77);SUCRA:0.688],and propranolol[RR:0.77,(95%CI:0.58–1.02);SUCRA:0.337].Similar findings were observed for liver-related *** ranked the *** RR of adverse events was 4.38,(95%CrI:0.33–161.4);SUCRA:0.530,followed by propranolol[RR:7.54,(95%CrI:1.90–47.89);SUCRA:0.360],and nadolol[RR:18.24,(95%CrI:91.51–390.90);SUCRA:0.158].Conclusions:Carvedilol is the preferred NSBB with better survival benefit and lower occurrence of adverse events among patients with gastroesophageal varices.

关键词： NSBB Carvedilol Nadolol Propranolol Varices Cirrhosis CPSH

Update in management of hepatocellular carcinoma in Eastern population

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World Journal of Hepatology 2015年第11期7卷 1562-1571页

作者： Kevin ka Wan Chu Tan To Cheung Department of Surgery the University of Hong Kong

Hepatocellular carcinoma(HCC) is one of the commonest malignant tumours in the East. Although the management of HCC in the West is mainly based on the Barcelona Clinic for Liver Cancer staging, it is considered too conservative by Asian countries where the number of HCC patients is huge. Scientific and clinical advances were made in aspects of diagnosis, staging, and treatment of HCC. HCC is well known to be associated with cirrhosis and the treatment of HCC must take into account the presence and stage of chronic liver disease. The major treatment modalities of HCC include:(1) surgical resection;(2) liver transplantation;(3) local ablation therapy;(4) transarterial locoregional treatment; and(5) systemic treatment. Among these, resection, liver transplantation and ablation therapy for small HCC are considered as curative treatment. Portal vein embolisation and the associating liver partition with portal vein ligation for staged hepatectomy may reduce dropout in patients with marginally resectable disease but the midterm and long-term results are still to be confirmed. Patient selection for the best treatment modality is the key to success of treatment of HCC. The purpose of current review is to provide a description of the current advances in diagnosis, staging, preoperative liver function assessment and treatment options for patients with HCC in the east.

关键词： Hepatocellular carcinoma Liver cirrhosis Treatment Management Evidence Survival Update

A potential red-emitting phosphor Ca_(2)YTaO_(6):Eu^(3+):Luminescence properties,thermal stability and applications for white LEDs

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Journal of Rare Earths 2021年第7期39卷 749-756,I0001页

作者： ka Ding Siru A Shuo Pang Leyan Shan Yaqi Zhang Pengfei Sun Bin Deng Ruijin Yu College of Chemistry&Pharmacy Northwest A&F UniversityYangling 712100China College of Innovation&Experiment Northwest A&F UniversityYangling 712100China College of Chemistry&Biology and Environmental Engineering Xiangnan UniversityChenzhou 423043China Hunan Provincial Key Laboratory of Xiangnan Rare-Precious Metals Compounds Research and Application Xiangnan UniversityChenzhou 423043China Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion Materials College of Materials and Chemical EngineeringChina Three Gorges UniversityYichang 443002China

A novel red-emitting phosphor tantalate Ca_(2)YTaO_(6):Eu^(3+)was synthesized by a solid-state *** purity and surface morphology of the phosphors were *** Ca_(2)YTaO_(6):Eu^(3+)phosphors show a sharp emission peak at 612 nm under near-ultraviolet(n-UV) at 395 nm because of the ^(5)D0→^(7)F_(2) transition of Eu^(3+).The optimal Eu^(3+)doping concentration in Ca_(2)YTaO_(6) is 40 mol% and the critical energy-transfer distance of Eu^(3+)ions was calculated to be 0.9 *** emission spectra of Ca_(2)YTaO_(6):Eu_(3+)from 300 to 480 K were *** thermal-quenching temperature(T_(0.5)) of Ca_(2)YTaO_(6):Eu^(3+)is above 480 *** color purity of Ca_(2)YTaO_(6):40 mol%Eu^(3+)is as high as 99.8%.The luminescence lifetime of Ca_(2)YTaO_(6):40 mol%Eu^(3+)was also *** high color purity and high thermal stability of Eu^(3+)-doped Ca_(2)YTaO_(6) phosphors contribute to its application value in white lightemitting diodes(w-LEDs).

关键词： Luminescence Tantalate Ca_(2)YTaO_(6):Eu^(3+) Light-emitting diodes Rare earths