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Hepatitis C virus and human immunodeficiency virus transmission routes: Differences and similarities 被引量:1
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作者 Francesca Cainelli 《World Journal of Hepatology》 CAS 2013年第5期234-236,共3页
Bouare et al found that hepatitis C virus (HCV) infection in Malian women is mainly transmitted through medical procedures with contaminated supplies, and that human immunodeficiency virus (HIV) transmission is predom... Bouare et al found that hepatitis C virus (HCV) infection in Malian women is mainly transmitted through medical procedures with contaminated supplies, and that human immunodeficiency virus (HIV) transmission is predominantly sexual. The results of this study confirm those of a recent case-control study in New York and Oregon which demonstrated that healthcare exposures represent an important source of new HCV infections in United States. HCV seroprevalence was only 0.2% in pregnant, young Malian women, indicating that hygiene improved in healthcare facilities over time. Heterosexual transmission of HCV is exceptional, and can occur, from males to females, in extremely rare occasions in case of vaginal mucosal damage or less rarely through anal intercourse. The Malian study did not show an association between HIV infection and hospitalization, transfusion, tattoo, dental care. Transmission by needle-stick injury occurs in 0.9%-2.2% of exposures from HCV-infected subjects and in 0.1%-0.3% of exposures from HIV-infected in- dividuals. HCV is therefore more transmissible through percutaneous exposure. 展开更多
关键词 HEPATITIS C VIRUS Human IMMUNODEFICIENCY VIRUS transmission Sub-Saharan Africa PREGNANT women
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In situ atomic-scale observation of size-dependent (de) potassiation and reversible phase transformation in tetragonal FeSe anodes
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作者 Ran Cai Lixia Bao +12 位作者 Wenqi Zhang Weiwei Xia Chunhao Sun Weikang Dong Xiaoxue Chang Ze Hua Ruiwen Shao Toshio Fukuda Zhefei Sun Haodong Liu Qiaobao Zhang Feng Xu Lixin Dong 《InfoMat》 SCIE CAS CSCD 2023年第1期161-171,共11页
Potassium-ion batteries(PIBs)are considered promising alternatives to lithium-ion batteries owing to cost-effective potassium resources and a suitable redox potential of-2.93 V(vs.-3.04 V for Li+/Li).However,the explo... Potassium-ion batteries(PIBs)are considered promising alternatives to lithium-ion batteries owing to cost-effective potassium resources and a suitable redox potential of-2.93 V(vs.-3.04 V for Li+/Li).However,the exploration of appro-priate electrode materials with the correct size for reversibly accommodating large K+ions presents a significant challenge.In addition,the reaction mecha-nisms and origins of enhanced performance remain elusive.Here,tetragonal FeSe nanoflakes of different sizes are designed to serve as an anode for PIBs,and their live and atomic-scale potassiation/depotassiation mechanisms are revealed for the first time through in situ high-resolution transmission electron micros-copy.We found that FeSe undergoes two distinct structural evolutions,sequen-tially characterized by intercalation and conversion reactions,and the initial intercalation behavior is size-dependent.Apparent expansion induced by the intercalation of K+ions is observed in small-sized FeSe nanoflakes,whereas unexpected cracks are formed along the direction of ionic diffusion in large-sized nanoflakes.The significant stress generation and crack extension originating from the combined effect of mechanical and electrochemical interactions are elucidated by geometric phase analysis and finite-element analysis.Despite the different intercalation behaviors,the formed products of Fe and K_(2)Se after full potassiation can be converted back into the original FeSe phase upon depotassiation.In particular,small-sized nanoflakes exhibit better cycling perfor-mance with well-maintained structural integrity.This article presents the first successful demonstration of atomic-scale visualization that can reveal size-dependent potassiation dynamics.Moreover,it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs. 展开更多
关键词 elucidated by geometric phase analysis and finite-element analysis. Despite the different intercalation behaviors the formed products of Fe and K 2 Se after full potassiation can be converted back into the original FESE phase upon depotassiation. In particular small-sized nanoflakes exhibit better cycling perfor- mance with well-maintained structural integrity. This article presents the first successful demonstration of ATOMIC-SCALE visualization that can reveal size- dependent potassiation dynamics. Moreover it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs. KEYWOR DS in situ transmission electron microscopy potassium-ion batteries potassium-ion storage mechanism SIZE-DEPENDENT effects TETRAGONAL FESE
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Perceived infection transmission routes, infection control practices, psychosocial changes, and management of COVID-19 infected healthcare workers in a tertiary acute care hospital in Wuhan: a cross-sectional survey 被引量:12
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作者 Ying-Hui Jin Qiao Huang +15 位作者 Yun-Yun Wang Xian-Tao Zeng Li-Sha Luo Zhen-Yu Pan Yu-Feng Yuan Zhi-Min Chen Zhen-Shun Cheng Xing Huang Na Wang Bing-Hui Li Hao Zi Ming-Juan Zhao Lin-Lu Ma Tong Deng Ying Wang Xing-Huan Wang 《Military Medical Research》 SCIE CAS CSCD 2020年第4期418-429,共12页
Background:Many healthcare workers were infected by coronavirus disease 2019(COVID-19)early in the epidemic posing a big challenge for epidemic control.Hence,this study aims to explore perceived infection routes,influ... Background:Many healthcare workers were infected by coronavirus disease 2019(COVID-19)early in the epidemic posing a big challenge for epidemic control.Hence,this study aims to explore perceived infection routes,influencing factors,psychosocial changes,and management procedures for COVID-19 infected healthcare workers.Methods:This is a cross-sectional,single hospital-based study.We recruited all 105 confirmed COVID-19 healthcare workers in the Zhongnan Hospital of Wuhan University from February 15 to 29,2020.All participants completed a validated questionnaire.Electronic consent was obtained from all participants.Perceived causes of infection,infection prevention,control knowledge and behaviour,psychological changes,symptoms and treatment were measured.Results:Finally,103 professional staff with COVID-19 finished the questionnaire and was included(response rate:98.1%).Of them,87 cases(84.5%)thought they were infected in working environment in hospital,one(1.0%)thought their infection was due to the laboratory environment,and 5(4.9%)thought they were infected in daily life or community environment.Swab of throat collection and physical examination were the procedures perceived as most likely causing their infection by nurses and doctors respectively.Forty-three(41.8%)thought their infection was related to protective equipment,utilization of common equipment(masks and gloves).The top three first symptoms displayed before diagnosis were fever(41.8%),lethargy(33.0%)and muscle aches(30.1%).After diagnosis,88.3%staff experienced psychological stress or emotional changes during their isolation period,only 11.7%had almost no emotional changes.Arbidol(Umifenovir;an anti-influza drug;69.2%)was the drug most commonly used to target infection in mild and moderate symptoms.Conclusion:The main perceived mode of transmission was not maintaining protection when working at a close distance and having intimate contact with infected cases.Positive psychological intervention is necessary. 展开更多
关键词 COVID-19 SARS-CoV-2 2019-nCoV Healthcare worker Healthcare professional Infection transmission route Psychosocial status
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A Direct Trust dependent Link State Routing Protocol Using Route Trusts for WSNs (DTLSRP)
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作者 Shaik Sahil Babu Arnab Raha Mrinal Kanti Naskar 《Wireless Sensor Network》 2011年第4期125-134,共10页
The traditional cryptographic security techniques are not sufficient for secure routing of message from source to destination in Wireless Sensor Networks (WSNs), because it requires sophisticated software, hardware, l... The traditional cryptographic security techniques are not sufficient for secure routing of message from source to destination in Wireless Sensor Networks (WSNs), because it requires sophisticated software, hardware, large memory, high processing speed and communication bandwidth. It is not economic and feasible because, depending on the application, WSN nodes are high-volume in number (hence, limited resources at each node), deployment area may be hazardous, unattended and/or hostile and sometimes dangerous. As WSNs are characterized by severely constrained resources and requirement to operate in an ad-hoc manner, security functionality implementation to protect nodes from adversary forces and secure routing of message from source node to base station has become a challenging task. In this paper, we present a direct trust dependent link state routing using route trusts which protects WSNs against routing attacks by eliminating the un-trusted nodes before making routes and finding best trustworthy route among them. We compare our work with the most prevalent routing protocols and show its benefits over them. 展开更多
关键词 Wireless Sensor Network (WSN) Geometric Mean (GM) Direct TRUST Indirect TRUST route TRUST (RT) Base Station (BS) Benevolent NODE MALICIOUS NODE Homogeneous Nodes PACKET Latency PACKET transmission Rate MATLAB
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QoS Aware Routing Protocol to Improve Packet Transmission in Shadow-Fading Environment for Mobile Ad Hoc Networks
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作者 T. Sangeetha K. K. Venkatesh Venkatesh +1 位作者 Rajesh   M. S. K. Manikandan 《Communications and Network》 2013年第3期611-617,共7页
In Shadow-Fading model, it is difficult to achieve higher Packet Delivery Ratio (PDR) due to the effects of large scale fading. The main goal of this paper is to improve the PDR in Shadow-Fading environment. To achiev... In Shadow-Fading model, it is difficult to achieve higher Packet Delivery Ratio (PDR) due to the effects of large scale fading. The main goal of this paper is to improve the PDR in Shadow-Fading environment. To achieve this objective a protocol has been proposed that discovers backup routes for active sessions. These backup routes salvage the packets of active session in case of active route failure. It is found by research that proactively maintaining backup routes for ac-tive sessions can noticeably improve the PDR in Shadow-Fading environment. This protocol has been implemented with a mechanism of having backup routes and simulations have been conducted by using both node disjoint paths and link disjoint paths. Comparisons have been made between new protocol as well as AODV protocol. Simulation has been carried out using Network Simulator 2 (NS2) and the results show that the proposed QoSAR protocol exhibits higher PDR than AODV protocol in Shadow-fading environment. 展开更多
关键词 Shadow-Fading Model ADHOC On Demand Distance Vector ROUTING (AODV) BACKUP routes Node DISJOINT PATHS Link DISJOINT PATHS Packet Delivery Ratio (PDR) Quality of Service Aware ROUTING (QoSAR)
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Asymptomatic Genital Infection of Human Papillomavirus in Pregnant Women and the Vertical Transmission Route 被引量:1
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作者 邓东锐 闻良珍 +1 位作者 陈雯 凌霞珍 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2005年第3期343-345,共3页
To further investigate the vertical transmission route of human papillomavirus (HPV) and the indication for the choice of mode of delivery, the infective status of 152 asymptomatic pregnant wemen and the maternal-feta... To further investigate the vertical transmission route of human papillomavirus (HPV) and the indication for the choice of mode of delivery, the infective status of 152 asymptomatic pregnant wemen and the maternal-fetal transmission were studied. By using general primers in polymerase chain reaction (GP-PCR) combined with restriction fragment length polymorphism analysis, HPV DNA positive rate in cervical secretions and venous blood in asymptomatic pregnant women was 36.21 % and 52.78 %, respectively, and the identified genotypes were mainly HPV_16 and _18. The maternal-fetal transmission rate of HPV via genital tract as well as blood was 40.91 % and 57.89 %, respectively. It was concluded that besides the transmission route of genital tract and amniotic fluid, there was also transplacental transmission of HPV in utero. Therefore,in our opinion, it is not an absolut indication to perform a cesarean delivery for the pregnant women with HPV asymtomatic genital infection. 展开更多
关键词 pregnant women human papillomavirus vertical transmission route polymerase chain reaction
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Improving the Transmission Security of Vein Images Using a Bezier Curve and Long Short-Term Memory
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作者 Ahmed H.Alhadethi Ikram Smaoui +1 位作者 Ahmed Fakhfakh Saad M.Darwish 《Computers, Materials & Continua》 SCIE EI 2024年第6期4825-4844,共20页
The act of transmitting photos via the Internet has become a routine and significant activity.Enhancing the security measures to safeguard these images from counterfeiting and modifications is a critical domain that c... The act of transmitting photos via the Internet has become a routine and significant activity.Enhancing the security measures to safeguard these images from counterfeiting and modifications is a critical domain that can still be further enhanced.This study presents a system that employs a range of approaches and algorithms to ensure the security of transmitted venous images.The main goal of this work is to create a very effective system for compressing individual biometrics in order to improve the overall accuracy and security of digital photographs by means of image compression.This paper introduces a content-based image authentication mechanism that is suitable for usage across an untrusted network and resistant to data loss during transmission.By employing scale attributes and a key-dependent parametric Long Short-Term Memory(LSTM),it is feasible to improve the resilience of digital signatures against image deterioration and strengthen their security against malicious actions.Furthermore,the successful implementation of transmitting biometric data in a compressed format over a wireless network has been accomplished.For applications involving the transmission and sharing of images across a network.The suggested technique utilizes the scalability of a structural digital signature to attain a satisfactory equilibrium between security and picture transfer.An effective adaptive compression strategy was created to lengthen the overall lifetime of the network by sharing the processing of responsibilities.This scheme ensures a large reduction in computational and energy requirements while minimizing image quality loss.This approach employs multi-scale characteristics to improve the resistance of signatures against image deterioration.The proposed system attained a Gaussian noise value of 98%and a rotation accuracy surpassing 99%. 展开更多
关键词 Image transmission image compression text hiding Bezier curve Histogram of Oriented Gradients(HOG) LSTM image enhancement Gaussian noise ROTATION
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Enabling Efficient Data Transmission in Wireless Sensor Networks-Based IoT Application
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作者 Ibraheem Al-Hejri Farag Azzedin +1 位作者 Sultan Almuhammadi Naeem Firdous Syed 《Computers, Materials & Continua》 SCIE EI 2024年第6期4197-4218,共22页
The use of the Internet of Things(IoT)is expanding at an unprecedented scale in many critical applications due to the ability to interconnect and utilize a plethora of wide range of devices.In critical infrastructure ... The use of the Internet of Things(IoT)is expanding at an unprecedented scale in many critical applications due to the ability to interconnect and utilize a plethora of wide range of devices.In critical infrastructure domains like oil and gas supply,intelligent transportation,power grids,and autonomous agriculture,it is essential to guarantee the confidentiality,integrity,and authenticity of data collected and exchanged.However,the limited resources coupled with the heterogeneity of IoT devices make it inefficient or sometimes infeasible to achieve secure data transmission using traditional cryptographic techniques.Consequently,designing a lightweight secure data transmission scheme is becoming essential.In this article,we propose lightweight secure data transmission(LSDT)scheme for IoT environments.LSDT consists of three phases and utilizes an effective combination of symmetric keys and the Elliptic Curve Menezes-Qu-Vanstone asymmetric key agreement protocol.We design the simulation environment and experiments to evaluate the performance of the LSDT scheme in terms of communication and computation costs.Security and performance analysis indicates that the LSDT scheme is secure,suitable for IoT applications,and performs better in comparison to other related security schemes. 展开更多
关键词 IoT LIGHTWEIGHT computation complexity communication overhead cybersecurity threats threat prevention secure data transmission Wireless Sensor Networks(WSNs) elliptic curve cryptography
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OFDM Wireless Downhole Transmission Systems and Proposed SLM Method for PAPR Reduction 被引量:4
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作者 Renze Luo Yupu Dang +1 位作者 Rui Li Jiao Yang 《Communications and Network》 2014年第1期9-14,共6页
At present, mud pulse transmission systems are widely used in downhole data transmission. But the systems are very low in transmission efficiency, only 5-10 bits/s, with very large anti-inter-symbol-interference (ISI)... At present, mud pulse transmission systems are widely used in downhole data transmission. But the systems are very low in transmission efficiency, only 5-10 bits/s, with very large anti-inter-symbol-interference (ISI). It cannot meet high requirements for high-speed transmission of modern logging system. The development of communication technology has laid some foundation for this requirement. For this purpose, the Orthogonal Frequency Division Multiplexing (OFDM) Wireless Downhole Transmission Systems are proposed for the first time because of their high transmission rate, anti-inter-symbol-interference (ISI), and high spectral efficiency, etc. Due to non-linear power amplifier (PA) of logging systems with limited dynamic range, the drawbacks of high peak-average power ratio (PAPR) may outweigh all the potential benefits of OFDM wireless downhole transmission systems. Selective mapping (SLM) method can reduce the PAPR of OFDM logging signals without distortion. But at the receiver, the conventional SLM method needs exact bits of side information (SI) to recover the data signal. The probability of erroneous SI detection has a significant influence on the error performance of the system. And individual transmissions of SI result in the reduction of bandwidth efficiency. To restore the exact data signal, our scheme codes the SI bits by linear block codes (LBC), and is easily decoded by syndrome decoding. And then the coding SI bits are superimposed onto the logging signals to omit SI bits transmission. The theory and simulation results show that the proposed method has better performance than the conventional one. Accordingly, the OFDM wireless downhole transmission systems can tackle the high PAPR problem, and highten the transmission rate of logging signals. 展开更多
关键词 ORTHOGONAL Frequency DIVISION MULTIPLEXING WIRELESS DOWNHOLE transmission Systems ORTHOGONAL Frequency DIVISION MULTIPLEXING (OFDM) Logging While Drilling (LWD) Peak-to-Average Power Ratio (PAPR) Selected Mapping (SLM)
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A Model with Traffic Routers, Dynamically Managing Signal Phases to Address Traffic Congestion in Real Time 被引量:1
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作者 Rajendra S. Parmar Bhushan Trivedi Aleksandar Stevanovic 《Journal of Transportation Technologies》 2018年第1期75-90,共16页
On-road Vehicular traffic congestion has detrimental effect on three lifelines: Economy, Productivity and Pollution (EPP). With ever increasing population of vehicles on road, traffic congestion is a major challenge t... On-road Vehicular traffic congestion has detrimental effect on three lifelines: Economy, Productivity and Pollution (EPP). With ever increasing population of vehicles on road, traffic congestion is a major challenge to the economy, productivity and pollution, notwithstanding continuous developments in alternative fuels, alternative sources of energy. The research develops accurate and precise model in real time which computes congestion detection, dynamic signaling algorithm to evenly distribute vehicle densities while ensuring avoidance of starvation and deadlock situation. The model incorporates road segment length and breadth, quality and achievable average speed to compute road capacity. Vehicles installed with GPS enabled devices provide their location, which enables computing road occupancy. Road occupancy is evaluated based on number of vehicles as well as area occupied by vehicles. Ratio of road occupancy and road capacity provides congestion index important to compute signal phases. The algorithm ensures every direction is serviced once during a signaling cycle ensuring no starvation. Secondly, the definition of minimum and maximum signal timings ensures against dead lock situation. A simulator is developed to validate the proposition and proves it can ease congestion by more than 50% which is better than any of the contemporary approaches offering 15% improvement. In case of higher congestion index, alternate routes are suggested based on evaluation of traffic density graphs for shortest route or knowledge database. The algorithm to compute shortest route is optimized drastically, reducing computation cost to 3*√2N vis-à-vis computation cost of N2 by classical algorithms. The proposal brings down the cost of implementation per traffic junction from USD 30,000 to USD 2000. 展开更多
关键词 Dynamic TRAFFIC Assignment INTELLIGENT Transportation Systems INTELLIGENT Vehicles ROAD TRAFFIC Control ROAD TRAFFIC Sensing TRAFFIC Management VEHICLE DETECTION VEHICLE Routing TRAFFIC Signals Vehicular CONGESTION DETECTION System Vehicular TRAFFIC VEHICLE Mobility Sensors
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Molecular study of HCV detection,genotypes and their routes of transmission in North West Frontier Province,Pakistan 被引量:5
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作者 Asher Zaman Safi Yasir Waheed +4 位作者 Joharia Sadat Solat-Ul-Islam Sadia Salahuddin Umar Saeed Muhammad Ashraf 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第7期532-536,共5页
Objective:To determine hepatitis C virus(HCV) genotypes and explore the associated risk factors in chronic HCY patients.Methods:A total of 116 patients with chronic hepatitis C were subjected to polymerase chain react... Objective:To determine hepatitis C virus(HCV) genotypes and explore the associated risk factors in chronic HCY patients.Methods:A total of 116 patients with chronic hepatitis C were subjected to polymerase chain reaction(PCR) based detection out of which 112 chronic HCV patients[53 male(47.32%),59 female(52.68%);mean age(43.76±16.40) years;mean BMI(23.8± 3.9)kg]were enrolled in this study.The frequency of 6 HCV genotypes and associated risk factors were evaluated from five districts of North West Frontier Province(NWFP).Results:Genotype 3was the most prevalent in 73 samples(65.17%) followed by genotype 1 in 24(21.42%) and genotype2 in 13(11.60%) samples.Genotype3 had significantly high prevalence(P=0.0002).The results showed that 48(42.85%) samples were infected with HCV 3a:25(22.32%) with 3b;14(12.50%) with 1a;10(8.92%)with 1b;11(9.82%) with 2a;2(1.78%) with 2b;and 2 were untypable.The distribution of HCV genotypes in Murdan.Charsadda,Peshawar.Sawabi and Nowshehra districts was different.Use of unsterile equipment lor medication,barbers and previous history of hospitalization were the main risk factors for HCV transmission.Conclusions:Cenotype 3a and 3b.1a.1b and 2a are the common genotypes in NWFP.Genotype 4.5.and 6 can not be found in a single sample.The level of awareness about various modes ot transmission of HCV among the population is found to be verv low. 展开更多
关键词 HCV GENOTYPES SUBTYPE 3a Risk factors NWFP transmission MOLECULAR STUDY PCR
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Virus-phytoplankton adhesion:a new WSSV transmission route to zooplankton 被引量:1
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作者 ZHANG Jiasong DONG Shuanglin +3 位作者 TIAN Xiangli DONG Yunwei LIU Xiangyi YAN Dongchun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第6期109-115,共7页
The pathogenicity of white spot syndrome virus (WSSV) to zooplankton species, rotifer Brachionus urceus (Linnaeus), copepod Acartia clausi (Giesbrecht) and mysid shrimp Neomysis awatschensis ( Brandt ), was es... The pathogenicity of white spot syndrome virus (WSSV) to zooplankton species, rotifer Brachionus urceus (Linnaeus), copepod Acartia clausi (Giesbrecht) and mysid shrimp Neomysis awatschensis ( Brandt ), was estimated by immersion challenge and virus - phytoplankton adhesion mute to investigate a potential new transmission mute of WSSV to zooplankton. WSSV succeeded in infecting these zooplankton species and nested-PCR revealed positive results for the virus - phytoplankton adhesion mute, whereas WSSV cannot infect zooplankton by immersion challenge. These results indicated that virus - phytoplankton adhesion route is a successful new transmission mute of WSSV to zooplankton and also implied that phytoplankton could be a carrier in WSSV transmission. 展开更多
关键词 virus - phytoplankton adhesion WSSV transmission route ZOOPLANKTON
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Homopteran Vector Biomarkers for Efficient Circulative Plant Virus Transmission are Conserved in Multiple Aphid Species and the Whitefly Bemisia tabaci 被引量:1
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作者 Michelle Cilia Michael Bereman +2 位作者 Tara Fish Michael J MacCoss stewart Gray 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第2期249-262,共14页
Plant viruses in the families Luteoviridae and Geminiviridae are phloem restricted and are transmitted in a persistent,circulative manner by homopteran insects.Using fluorescence 2-D difference gel electrophoresis to ... Plant viruses in the families Luteoviridae and Geminiviridae are phloem restricted and are transmitted in a persistent,circulative manner by homopteran insects.Using fluorescence 2-D difference gel electrophoresis to compare the proteomes of F2 genotypes of Schizaphis graminum segregating for virus transmission ability,we recently discovered a panel of protein biomarkers that predict vector competency.Here we used aphid and whitefly nucleotide and expressed sequence tag database mining to test whether these biomarkers are conserved in other homopteran insects.S.graminum gene homologs that shared a high degree of predicted amino acid identity were discovered in two other aphid species and in the whitefly Bemisia tabaci.Selected reaction monitoring mass spectrometry was used to validate the expression of these biomarkers proteins in multiple aphid vector species.The conservation of these proteins in multiple insect taxa that transmit plant viruses along the circulative transmission pathway creates the opportunity to use these biomarkers to rapidly identify insect populations that are the most efficient vectors and allow them to be targeted for control prior to the spread of virus within a crop. 展开更多
关键词 APHID WHITEFLY Schizaphis graminum Bemisia tabaci Acyrthosiphon pisum Toxoptera citricida Myzuspersicae proteomics biomarker circulative transmission BEGOMOVIRUS LUTEOVIRUS GEMINIVIRUS leaflaopper selected reaction monitoring SRM mass spectrometry targeted proteomics Skyline
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Beliefs and practices of young women on utilization of prevention of mother to child transmission of HIV services in Malawi
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作者 Sadandaula Rose Muheriwa Angela Chimwaza +2 位作者 Alfred O. Maluwa Betty Mkwinda Nyasulu Mercy Pindani 《Health》 2013年第7期1172-1179,共8页
This study explored beliefs and actual practices of young women on utilization of Prevention of Mother to Child Transmission (PMTCT) of HIV services in Balaka district of Southern Malawi. The study design wascross sec... This study explored beliefs and actual practices of young women on utilization of Prevention of Mother to Child Transmission (PMTCT) of HIV services in Balaka district of Southern Malawi. The study design wascross sectional which utilized qualitative data collection and analysis methods. In-depth interviews were conducted on 12 young mothers of 15 to 24 years old. The respondents were drawn from 6 health centres in the district during their visits to either the under-five clinic, HIV and AIDS support groups or HIV follow up clinics. Data were analyzed using thematic analysis approach. Overall the respondents had positive beliefs on utilization of PMTCT services. They believed that adherence to PMTCT guidelines such as condom use, taking of Nevirapine (NVP) and exclusive breastfeeding protected the baby from contracting the virus. Nevertheless, all respondents believed that HIV testing was mandatory and that early weaning caused malnutrition and death of babies. Actual practice was very low. Very few young mothers breastfed exclusively, weaned their babies abruptly and took NVP as recommended. Not all positive beliefs translated into positive behavior. Lack of male support, inability of the midwives to provide comprehensive care to HIV infected mothers and their infants, and fear of stigma and discrimination were other factors that hindered utilization of PMTCT services. Culture was also a major barrier because traditionally babies are expected to be breastfed and supplements are fed to babies too. Therefore, there is a need to mobilize communities on PMTCT of HIV. Education programmes in HIV should emphasize behavior change interventions and should focus on both men and women and significant others. There is also need to intensify monitoring and evaluation of health workers’ activities to ensure that beliefs translate into positive behavior. 展开更多
关键词 PREVENTION of Mother to Child transmission of HIV HIV Positive Young Women BELIEFS on PMTCT SERVICES PMTCT Practice EXCLUSIVE Breast Feeding
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Design and Experimental Research on Seedling Pick-Up Mechanism of Planetary Gear Train with Combined Non-circular Gear Transmission 被引量:11
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作者 Yaxin Yu Jikun Liu +4 位作者 Bingliang Ye Gaohong Yu Xuejun Jin Liang Sun Junhua Tong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期42-54,共13页
Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent ... Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent transmission, and a concave and convex locking arc device, has a large rigid impact. To solve these problems, according to the design requirements for a dryland plug seedling transplanting mechanism, a rotary seedling pick-up mechanism of a planetary gear train with combined non-circular gear transmission of incomplete eccentric circular and noncircular gears was proposed. This has the characteristics of two-times greater fluctuation of the transmission ratio in a cycle, and can achieve a non-uniform continuous drive. Through analysis of the working principle of the seedling pick-up mechanism, its kinematics model was established. The human–computer interaction optimization method and self-developed computer-aided analysis and optimization software were used to obtain a set of parameters that satisfy the operation requirements of the seedling pick-up mechanism. According to the optimized parameters, the structure of the seedling pick-up mechanism was designed, a virtual prototype of the mechanism was created, and a physical prototype was manufactured. A virtual motion simulation of the mechanism was performed, high-speed photographic kinematics tests were conducted, and the kinematic properties of the physical prototype were investigated, whereby the correctness of the theoretical model and the optimized design of the mechanism were verified. Further, laboratory seedling pick-up tests were conducted. The success ratio of seedling pick-up was 93.8% when the seedling pick-up efficiency of the mechanism was 60 plants per minute per row, indicating that the mechanism has a high efficiency and success ratio for seedling pick-up and can be applied to a dryland plug seedling transplanter. 展开更多
关键词 Dryland plug SEEDLING transplanter Rotary SEEDLING PICK-UP MECHANISM transmission ratio Non-uniform continuous transmission COMBINED NON-CIRCULAR gear transmission Optimization design
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Model of an Atom by Analogy with the Transmission Line
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作者 Milan Perkovac 《Journal of Modern Physics》 2013年第7期899-903,共5页
Model of an atom by analogy with the transmission line is derived using Maxwell’s equations and Lorentz’ theory of electrons. To be realistic such a model requires that the product of the structural coefficient of L... Model of an atom by analogy with the transmission line is derived using Maxwell’s equations and Lorentz’ theory of electrons. To be realistic such a model requires that the product of the structural coefficient of Lecher’s transmission lines σ and atomic number Z is constant. It was calculated that this electromechanical constant is 8.27756, and we call it structural constant. This constant builds the fine-structure constant 1/α = 137.036, and with permeability μ, permittivity ε and elementary charge e builds Plank’s constant h. This suggests the electromagnetic character of Planck’s constant. The relations of energy, frequency, wavelength and momentum of electromagnetic wave in an atom are also derived. Finally, an equation, similar to Schrodinger’s equation, was derived, with a clear meaning of the wave function, which represents the electric or magnetic field strength of the observed electromagnetic wave. 展开更多
关键词 Lecher transmission Line Lorentz Theory of ELECTRONS Maxwells Equations Model of ATOM PLANCK CONSTANT Structural CONSTANT Transverse Mass Wave Equation
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Relationship between Maternal PBMC HBV cccDNA and HBV Serological Markers and its Effect on HBV Intrauterine Transmission 被引量:9
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作者 WANG Dan Dan YI Lin Zhu +7 位作者 WU Li Na YANG Zhi Qing HAO Hai Yun SHI Xiao Hong WANG Bo FENG Shu Ying FENG Yong Liang WANG Su Ping 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2019年第5期315-323,共9页
Objective To investigate the relationship between maternal peripheral blood mononuclear cells (PBMC) hepatitis B virus(HBV) covalenty closed circular deoxyribonucleic acid(cccDNA) and other HBV serological markers and... Objective To investigate the relationship between maternal peripheral blood mononuclear cells (PBMC) hepatitis B virus(HBV) covalenty closed circular deoxyribonucleic acid(cccDNA) and other HBV serological markers and its effects on HBV intrauterine transmission. Methods We enrolled 290 newborns and their hepatitis B surface antigen(HBsAg) positive mothers. HBV cccDNA in PBMC and HBV DNA in serum were detected by a real‐time PCR‐TaqM an probe while HBV serological markers were detected with an electrochemiluminescence immunoassay. Results There was a positive correlation between the levels of PBMC HBV cccD NA and serum HBV DNA and HBeA g(r = 0.436 and 0.403, P < 0.001). The detection rate of pattern A [‘HBsA g(+), HBeA g(+), and anti‐HBc(+)’] was significantly higher in the PBMC HBV cccD NA positive group than in the control group(χ^2 = 48.48, P < 0.001). There was a significant association between HBV intrauterine transmission and PBMC HBV cccD NA(χ^2 = 9.28, P = 0.002). In the presence of serum HBV DNA, HBeA g, and PBMC HBV cccD NA, the risk of HBV intrauterine transmission was three times higher(OR = 3.69, 95% CI: 1.30‐10.42) than that observed in their absence. The risk of HBV intrauterine transmission was the greatest(OR = 5.89, 95% CI: 2.35‐14.72) when both PBMC HBV cccD NA and pattern A were present. A Bayesian network model showed that maternal PBMC HBV cccD NA was directly related to HBV intrauterine transmission. Conclusion PBMC HBV cccDNA may be a direct risk factor for HBV intrauterine transmission. Our study suggests that serological markers could be combined with PBMC‐related markers in prenatal testing. 展开更多
关键词 Hepatitis B virus INTRAUTERINE transmission Peripheral blood MONONUCLEAR cells Covalently closed circular deoxyribonucleic acid SEROLOGICAL markers
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CoopAI-Route: DRL Empowered Multi-Agent Cooperative System for Efficient QoS-Aware Routing for Network Slicing in Multi-Domain SDN
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作者 Meignanamoorthi Dhandapani V.Vetriselvi R.Aishwarya 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2449-2486,共38页
The emergence of beyond 5G networks has the potential for seamless and intelligent connectivity on a global scale.Network slicing is crucial in delivering services for different,demanding vertical applications in this... The emergence of beyond 5G networks has the potential for seamless and intelligent connectivity on a global scale.Network slicing is crucial in delivering services for different,demanding vertical applications in this context.Next-generation applications have time-sensitive requirements and depend on the most efficient routing path to ensure packets reach their intended destinations.However,the existing IP(Internet Protocol)over a multi-domain network faces challenges in enforcing network slicing due to minimal collaboration and information sharing among network operators.Conventional inter-domain routing methods,like Border Gateway Protocol(BGP),cannot make routing decisions based on performance,which frequently results in traffic flowing across congested paths that are never optimal.To address these issues,we propose CoopAI-Route,a multi-agent cooperative deep reinforcement learning(DRL)system utilizing hierarchical software-defined networks(SDN).This framework enforces network slicing in multi-domain networks and cooperative communication with various administrators to find performance-based routes in intra-and inter-domain.CoopAI-Route employs the Distributed Global Topology(DGT)algorithm to define inter-domain Quality of Service(QoS)paths.CoopAI-Route uses a DRL agent with a message-passing multi-agent Twin-Delayed Deep Deterministic Policy Gradient method to ensure optimal end-to-end routes adapted to the specific requirements of network slicing applications.Our evaluation demonstrates CoopAI-Route’s commendable performance in scalability,link failure handling,and adaptability to evolving topologies compared to state-of-the-art methods. 展开更多
关键词 6G MULTI-DOMAIN MULTI-AGENT ROUTING DRL SDN
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A Novel Fractional Dengue Transmission Model in the Presence of Wolbachia Using Stochastic Based Artificial Neural Network
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作者 Zeshan Faiz Iftikhar Ahmed +1 位作者 Dumitru Baleanu Shumaila Javeed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期1217-1238,共22页
The purpose of this research work is to investigate the numerical solutions of the fractional dengue transmission model(FDTM)in the presence of Wolbachia using the stochastic-based Levenberg-Marquardt neural network(L... The purpose of this research work is to investigate the numerical solutions of the fractional dengue transmission model(FDTM)in the presence of Wolbachia using the stochastic-based Levenberg-Marquardt neural network(LM-NN)technique.The fractional dengue transmission model(FDTM)consists of 12 compartments.The human population is divided into four compartments;susceptible humans(S_(h)),exposed humans(E_(h)),infectious humans(I_(h)),and recovered humans(R_(h)).Wolbachia-infected and Wolbachia-uninfected mosquito population is also divided into four compartments:aquatic(eggs,larvae,pupae),susceptible,exposed,and infectious.We investigated three different cases of vertical transmission probability(η),namely when Wolbachia-free mosquitoes persist only(η=0.6),when both types of mosquitoes persist(η=0.8),and when Wolbachia-carrying mosquitoes persist only(η=1).The objective of this study is to investigate the effectiveness of Wolbachia in reducing dengue and presenting the numerical results by using the stochastic structure LM-NN approach with 10 hidden layers of neurons for three different cases of the fractional order derivatives(α=0.4,0.6,0.8).LM-NN approach includes a training,validation,and testing procedure to minimize the mean square error(MSE)values using the reference dataset(obtained by solving the model using the Adams-Bashforth-Moulton method(ABM).The distribution of data is 80% data for training,10% for validation,and,10% for testing purpose)results.A comprehensive investigation is accessible to observe the competence,precision,capacity,and efficiency of the suggested LM-NN approach by executing the MSE,state transitions findings,and regression analysis.The effectiveness of the LM-NN approach for solving the FDTM is demonstrated by the overlap of the findings with trustworthy measures,which achieves a precision of up to 10^(-4). 展开更多
关键词 WOLBACHIA DENGUE neural network vertical transmission mean square error LEVENBERG-MARQUARDT
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The Transmission,Establishment and Cross-cultural Integration of Chinese Medicine in the Mainstream Healthcare,through the Eyes of a Generation of Visionaries and Pioneers
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作者 Ioannis Solos Charles Buck 《Chinese Medicine and Culture》 2024年第1期1-4,共4页
It has historically been very difficult to trace the history of the westward transmission of Chinese medicine through the accounts of its protagonists. Many of the early scholars such as Jack Worsley, Dick Van Buren, ... It has historically been very difficult to trace the history of the westward transmission of Chinese medicine through the accounts of its protagonists. Many of the early scholars such as Jack Worsley, Dick Van Buren, and Joe Goodman were reluctant to divulge information about the source of their knowledge, or their professional qualifications. Others, such as John Shen and Hong Yuan-bain were early 20th century immigrants who transmitted highly personalized versions of acupuncture and Chinese medicine to select disciples. Eventually, a new class of scholars appeared, including names such as Ted Kaptchuk, Peter Deadman, Nigel Wiseman, William Morris, Peter Eckman, John Mc Donald, Charles Buck, and the late Giovanni Maciocia who looked for answers back in China, developed translation methodologies and terminology, compiled the main textbooks currently in use at TCM colleges, overcame enormous scholastic adversity, developed courses and pursued the regulation and accreditation of TCM in various countries. This special issue synopsizes the path towards the global acculturation of TCM over the last 50 years, the main protagonists, the enormous accomplishments they have achieved for the profession, their philosophy, their clinical perspectives and visions for the future. 展开更多
关键词 Chinese medicine Cross-cultural integration Westward transmission James Reston Acupuncture History
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