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The immune system:uncharted pathways between senses and the brain
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作者 Noelia Casares Mar Cuadrado-Tejedor +1 位作者 Ana García-Osta Juan JoséLasarte 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1173-1174,共2页
Humans and animals use the classic five senses-sight,hearing,touch,smell,and taste-to detect and monitor their environment,with the sense of position and movement often referred to as the sixth sense.The perception of... Humans and animals use the classic five senses-sight,hearing,touch,smell,and taste-to detect and monitor their environment,with the sense of position and movement often referred to as the sixth sense.The perception of external signals through the senses is essential to an organism's survival,transmitting signals to the central nervous system(CNS)and prompting physiological changes in other biological systems.In addition to the direct effects of sense-induced mediators in the brain. 展开更多
关键词 PROMPT system transmitting
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Assessment of albendazole efficacy against Ascaris lumbricoides at three sites of Andhra Pradesh,Odisha,and Kerala in India
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作者 Vinay Garg Ankur Garg +6 位作者 Shubha Garg Sudhir Kumar Jain Tanzin Dikid Saurabh Jain Jitendra Manjhi Antonio Montresor Atul Goel 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第7期310-316,共7页
Objective:To assess efficacy of albendazole against Ascaris(A.)lumbricoides among school-children at three sites of Rajahmundry,Sundergarh and Wayanad.Methods:Sites were selected based on soil-transmitted helminths pr... Objective:To assess efficacy of albendazole against Ascaris(A.)lumbricoides among school-children at three sites of Rajahmundry,Sundergarh and Wayanad.Methods:Sites were selected based on soil-transmitted helminths prevalence,different sociocultural-geographical characteristics and operational feasibility.9-12 Years old children from 14 schools were included.The study was conducted in two rounds:baseline&follow up survey.All eligible children found positive for A.lumbricoides at baseline were administered supervised single tablet albendazole 400 mg under the National Deworming Day Initiative.During post-treatment follow-up survey,eligible children who provided second stool sample were included in the final analysis.Stool samples were examined using WHO recommended Kato-Katz technique.Efficacy was estimated based on cure rate(CR)and Fecal Egg Count Reduction Rate(FECRR)among children found positive in baseline and follow-up surveys.Results:328 Out of 625(52.5%)were found positive for A.lumbricoides in the baseline survey and 85 out of 178 samples(47.8%)during post-treatment follow-up survey.Overall,the estimated CR was 52.2%.FECRR(95%CI)for albendazole was 72.6%(79.2%-66.0%).The FECRR was highest in East Godaveri[89.7%(96.8%-82.6%)],followed by Sundergarh[86.4%(95.3%-77.5%)]and Wayanad[69%(81.7%-56.4%)].Conclusions:Our study confirmed overall reduction in FEC although with varying albendazole efficacy for A.lumbricoides infection at three different locations in India.However,these finding may be assessed in context of ongoing MDA under Filaria control program and further studies by in vivo as well as in vitro methods are required to reach to a conclusion on possible resistance if any. 展开更多
关键词 Soil transmitted helminths Ascaris lumbricoides ALBENDAZOLE EFFICACY
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Transmit Power Minimization for IRS-Assisted NOMA-UAV Networks
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作者 Zhao Chen Pang Xiaowei +4 位作者 Tang Jie Liu Mingqian Zhao Nan Zhang Xiuyin Wang Xianbin 《China Communications》 SCIE CSCD 2024年第5期137-152,共16页
The flexibility of unmanned aerial vehicles(UAVs)allows them to be quickly deployed to support ground users.Intelligent reflecting surface(IRS)can reflect the incident signal and form passive beamforming to enhance th... The flexibility of unmanned aerial vehicles(UAVs)allows them to be quickly deployed to support ground users.Intelligent reflecting surface(IRS)can reflect the incident signal and form passive beamforming to enhance the signal in the specific direction.Motivated by the promising benefits of both technologies,we consider a new scenario in this paper where a UAV uses non-orthogonal multiple access to serve multiple users with IRS.According to their distance to the UAV,the users are divided into the close users and remote users.The UAV hovers above the close users due to their higher rate requirement,while the IRS is deployed near the remote users to enhance their received power.We aim at minimizing the transmit power of UAV by jointly optimizing the beamforming of UAV and the phase shift of IRS while ensuring the decoding requirement.However,the problem is non-convex.Therefore,we decompose it into two sub-problems,including the transmit beamforming optimization and phase shift optimization,which are transformed into second-order cone programming and semidefinite programming,respectively.We propose an iterative algorithm to solve the two sub-problems alternatively.Simulation results prove the effectiveness of the proposed scheme in minimizing the transmit power of UAV. 展开更多
关键词 intelligent reflecting surface nonorthogonal multiple access phase shift optimization transmit beamforming optimization unmanned aerial vehicle
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A Survey of Digital Content Required for STD Prevention Education Taught by School Nurses
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作者 Tomoko Nakamura 《Health》 2024年第4期350-370,共21页
Purpose: In recent years, there has been concern in Japan about the increase in STDs among adolescents aged 15 - 19. In order to prevent STDs and guide adolescents toward desirable sexual behavior, this study’s goal ... Purpose: In recent years, there has been concern in Japan about the increase in STDs among adolescents aged 15 - 19. In order to prevent STDs and guide adolescents toward desirable sexual behavior, this study’s goal was to examine the actual state of STD prevention education taught by school nurses as part of the school curriculum, as well as the kinds of digital content they wish to have for teaching on the subject. Method: An anonymous, self-administered questionnaire was distributed by email and leaflet. Targeting the 100 valid responses received from the surveyed school nurses, descriptive statistics were made for each survey item and comparisons were made between the early- and mid-career groups based on years of experience. Results: 70.0% of respondents reported teaching about STDs in Health & Physical Education classes. School nurses in the early-career group used ready-made materials, while the mid-career group used both ready-made and self-made materials. 95% of respondents reported that they had little or no knowledge of STDs, while 84% reported that they were “good” or “fairly good” at teaching classes on sexuality. Both groups reported difficulty with the topics of “phimosis” and “nocturnal emissions” in the physiological category, “sexual behavior” in the “sex-adjacent” category, and “sexual and reproductive issues” in the psychosocial category. Respondents expressed a need for digital content covering the topics of “sexual violence”, “sexual abuse”, “sexually transmitted diseases”, and “how to turn down sex”. The mid-career group desired digital content for more items than the early-career group, with significant differences in the pathogens involved in sexually transmitted diseases and sex-adjacent items. 32.0% of respondents answered that they had done self-study for sex education classes in the past three years, and both groups desired self-study on “sexually transmitted diseases”, with the mid-career group significantly higher than the early-career group on “cervical cancer & HPV”, “emergency contraceptives”, and “media literacy”. Conclusion: Health & Physical Education is the main subject that covers STDs, and pre-existing materials are commonly used. It is expected that this is due to nurses’ busy schedules and the fact that only one school nurse is assigned to each school. The data collected suggested that nurse teachers want categorized digital content that can be used in the classes they are responsible for, rather than educational content on topics they are not comfortable with. In addition, given the changing environment surrounding sex, it was clear that they wish to understand the realities and needs of the high school students they teach, and desire self-study opportunities to improve their teaching methods. 展开更多
关键词 High School Students Sexually Transmitted Diseases Digital Content School Nurses
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Parents’s knowledge and awareness about hepatitis B can influence the vaccination of their children
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作者 Nanda Chhavi Geetika Srivastava +4 位作者 Mariya Waseem Abhishek Yadav Surender Singh Rajani Singh Amit Goel 《World Journal of Virology》 2024年第2期96-106,共11页
BACKGROUND Birth-dose(Hep-BD)followed by three additional doses(Hep-B3)of hepatitis B virus(HBV)vaccine are key to eliminating HBV by 2030.Unfortunately,Hep-BD and Hep-B3 coverage in our country is poor.AIM To studied... BACKGROUND Birth-dose(Hep-BD)followed by three additional doses(Hep-B3)of hepatitis B virus(HBV)vaccine are key to eliminating HBV by 2030.Unfortunately,Hep-BD and Hep-B3 coverage in our country is poor.AIM To studied the parent’s knowledge and awareness about HBV infection,its prevention,consequences and vaccination.METHODS Parents of 6 months to 8 years old children were interviewed to assess their knowledge&awareness about hepatitis B,its transmission,prevention,illness caused by this,and vaccination.Eighteen close-ended questions were admini-stered,and responses were recorded as‘yes’,‘no’,or‘not sure’.HBV knowledge score was calculated based on the sum of correct answers.Each correct response scored one point and incorrect,missing or‘not sure’responses received no points.Categorical data are presented as number(%)and numerical data are expressed as median.Data were compared using Chi2 tests and level of significance was kept as P<0.05.RESULTS Parents(58.3%mothers)of 384 children(89.9%age<5 years;82%age-appropriately vaccinated)were included.Three hundred and twenty-two(83.9%)children were Hep-B3 vaccinated.94.3%,87.5%,and 29.2%parents knew about polio,tetanus,and hepatitis B vaccine.Overall,41.2%,15.8%,and 23%parents knew about hepatitis B transmission,consequences of infection,and prevention respectively.Only 7.6%parents knew about three-dose schedule of hepatitis B vaccination.Only 23%parents believed that vaccine could prevent HBV,15.7%knew that HBV affects liver.Parents of Hep-B3 vaccinated children were significantly more aware about HBV than the parents of unvaccinated children(P<0.05 for 17/18 questions).CONCLUSION The knowledge and awareness among the parents about hepatitis B is poor.The Increasing knowledge/awareness about HBV among parents may improve Hep-B3 vaccination coverage. 展开更多
关键词 Hepatitis B Viral hepatitis CIRRHOSIS Hepatocellular carcinoma Hepatotropic viruses Transfusion transmitted infection Mother to child transmission
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Seroprevalence Survey of HIV and Hepatitis B Virus and Behavioral Characteristics among Heavy Truck Drivers along Port Sudan-Khartoum Highways
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作者 Sara S. Osman Adam A. Mattar Omnia M. Hamid 《Open Journal of Medical Microbiology》 2024年第1期11-22,共12页
The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The pr... The prevalence of human immunodeficiency virus (AIDS) and hepatitis B virus among heavy truck drivers and their assistants has been well documented globally in correlation with their behavioral characteristics. The present study aimed to screen for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and behavioral characteristics among heavy truck drivers in Port Sudan. A cross-sectional study was conducted on 274 heavy truck drivers and their assistants who used the highway Port Sudan-Khartoum in Port Sudan city during 2019-2021. Data on behavioral characteristics and substance use habits were collected using a structured questionnaire, and an ELISA test was used to screen for HIV and HBV infections in the study participants. The chi-square test, odds ratio, and confidence intervals were used to find the association between behavioral characteristics and seropositive HIV/HBV. Of the 274 enrolled participants, the seroprevalence rates of HIV were 2.7% and HBV was 23.7%. Ninety-four (34.3%) of them had a history of high-risk sexual behavior outside of marriage;only two (0.7%) used condoms;14.2% of participants reported alcohol use;and 1.1% reported drug use. Univariate analysis revealed that having a sex history outside of marriage with ≥1 sex partner and never using a condom with a spouse or casual partner were significant risk factors for HIV and HBV among drivers. Fortunately, we found that most of the drivers reported low alcohol and drug use. Concerning this study, the seroprevalence of HIV and HBV is highly associated with a history of having sex outside of marriage and sexual behavior among truck drivers and assistances. Additional studies are needed to further investigate other STIs and behavioral characteristics associated with factors in truck drivers/assistance in different truck stop regions in Sudan. 展开更多
关键词 Sexual Transmitted Infection Port Sudan Truck Drivers/Assistance
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Discrete Phase Shifts Control and Beam Selection in RIS-Aided MISO System via Deep Reinforcement Learning 被引量:1
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作者 Dongting Lin Yuan Liu 《China Communications》 SCIE CSCD 2023年第8期198-208,共11页
Reconfigurable intelligent surface(RIS)for wireless networks have drawn lots of attention in both academic and industry communities.RIS can dynamically control the phases of the reflection elements to send the signal ... Reconfigurable intelligent surface(RIS)for wireless networks have drawn lots of attention in both academic and industry communities.RIS can dynamically control the phases of the reflection elements to send the signal in the desired direction,thus it provides supplementary links for wireless networks.Most of prior works on RIS-aided wireless communication systems consider continuous phase shifts,but phase shifts of RIS are discrete in practical hardware.Thus we focus on the actual discrete phase shifts on RIS in this paper.Using the advanced deep reinforcement learning(DRL),we jointly optimize the transmit beamforming matrix from the discrete Fourier transform(DFT)codebook at the base station(BS)and the discrete phase shifts at the RIS to maximize the received signal-to-interference plus noise ratio(SINR).Unlike the traditional schemes usually using alternate optimization methods to solve the transmit beamforming and phase shifts,the DRL algorithm proposed in the paper can jointly design the transmit beamforming and phase shifts as the output of the DRL neural network.Numerical results indicate that the DRL proposed can dispose the complicated optimization problem with low computational complexity. 展开更多
关键词 reconfigurable intelligent surface discrete phase shifts transmit beamforming deep reinforcement learning
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Hybrid absorbing boundary condition based on transmitting boundary and its application in 3D fractional viscoacoustic modeling
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作者 Song-Ling Li Ying Shi +2 位作者 Ning Wang Wei-Hong Wang Xuan Ke 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期840-856,共17页
An accurate numerical simulation for wave equations is essential for understanding of wave propagation in the earth's interior as well as full waveform inversion and reverse time migration. However, due to computa... An accurate numerical simulation for wave equations is essential for understanding of wave propagation in the earth's interior as well as full waveform inversion and reverse time migration. However, due to computational cost and hardware capability limitations, numerical simulations are often performed within a finite domain. Thus, an adequate absorbing boundary condition (ABC) is indispensable for obtaining accurate numerical simulation results. In this study, we develop a hybrid ABC based on a transmitting boundary, which is referred to as THABC, to eliminate artificial boundary reflections in 3D second-order fractional viscoacoustic numerical simulations. Furthermore, we propose an adaptive weighted coefficient to reconcile the transmitting and viscoacoustic wavefields in THABC. Through several numerical examples, we determine that the proposed THABC approach is characterized by the following benefits. First, with the same number of absorbing layers, THABC exhibits a better ability in eliminating boundary reflection than traditional ABC schemes. Second, THABC is more effective in computation, since it only requires the wavefields at the current and last time steps to solve the transmitting formula within the absorbing layers. Benefiting from a simple but effective combination between the transmitting equation and the second-order wave equation, our scheme performs well in the 3D fractional Laplacian viscoacoustic numerical simulation. 展开更多
关键词 Hybrid absorbing boundary Numerical simulation Transmitting boundary Fractional viscoacoustic wave equation
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Dynamic characterization of tailing dam using fully coupled dynamic analysis with different boundary conditions-a case study
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作者 Thanikella Vijayasri 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第4期995-1013,共19页
The seismic response analysis of a tailing dam is studied using a fully coupled effective stress approach in conjunction with an advanced multi yield surface plastic constitutive model for tailing material.Strain cont... The seismic response analysis of a tailing dam is studied using a fully coupled effective stress approach in conjunction with an advanced multi yield surface plastic constitutive model for tailing material.Strain controlled static and cyclic triaxial tests were carried out to obtain the constitutive model for the tailing material.The tailing materials were collected from the Rampura Agucha tailing dam(Rajasthan State,India).A 2D nonlinear finite element(FE)model was then developed using different boundary conditions from the tailing embankment constructed using the downstream and upstream method of rising using OpenSees software.In first case,the model boundary was fixed in both the X and Y directions,and in the second case,viscous dashpots were introduced for both side and horizontal boundaries.The model was validated with experimental results on tailing material.Analyses were carried out considering five different earthquake motions,which were applied at the base.Comparisons of the different boundary conditions in terms of displacement flow vectors,pore pressure and stress-strain curves during shaking are presented.From the analysis,it was observed that the viscous boundary condition replicates the actual field conditions more accurately than the fixed boundary condition.In addition,it was found that the tailing embankment constructed by the downstream and upstream method of rising is not susceptible to liquefaction and lateral spreading for earthquake motions,even for a magnitude>5.5. 展开更多
关键词 tailing embankment cyclic triaxial test seismic analysis liquefaction potential transmitting and fixed boundary conditions
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Colorectal motility patterns and psychiatric traits in functional constipation and constipation-predominant irritable bowel syndrome:A study from China
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作者 Chao-Lan Lv Geng-Qing Song +6 位作者 Jie Liu Wei Wang Yi-Zhou Huang Bo Wang Jia-Shuang Tian Meng-Qing Yin Yue Yu 《World Journal of Gastroenterology》 SCIE CAS 2023年第41期5657-5667,共11页
BACKGROUND Functional constipation(FC)and constipation-predominant irritable bowel syndrome(IBS-C)represent a spectrum of constipation disorders.However,the majority of previous clinical investigations have focused on... BACKGROUND Functional constipation(FC)and constipation-predominant irritable bowel syndrome(IBS-C)represent a spectrum of constipation disorders.However,the majority of previous clinical investigations have focused on Western populations,with limited data originating from China.AIM To determine and compare the colorectal motility and psychiatric features of FC and IBS-C in an Eastern Chinese population.METHODS Consecutive chronic constipation patients referred to our motility clinic from December 2019 to February 2023 were enrolled.FC and IBS-C diagnoses were established using ROME IV criteria,and patients underwent high-resolution anorectal manometry(ARM)and a colonic transmit test using the Sitz marker study.Constipation-related symptoms were obtained through questionnaires.Anxiety and depression were assessed by the Hamilton anxiety rating scale and the Hamilton Depression Rating Scale-21.The clinical characteristics and colorectal motility patterns of FC and IBS-C patients were compared.RESULTS No significant differences in sex,age or abdominal discomfort symptoms were observed between IBS-C and FC patients(all P>0.05).The proportion of IBS-C patients with delayed colonic transit was higher than that of patients with FC(36.63%vs 15.91%,P<0.05),while rectosigmoid accumulation of radiopaque markers was more common in the FC group than in the IBS-C group(50%vs 26.73%,P<0.05).Diverse proportions of these dyssynergic patterns were noted within both the FC and IBS-C groups by ARM.IBS-C patients were found to have a higher prevalence of depression than FC patients(66.30%vs 42.42%,P<0.05).The scores for feelings of guilt,suicide,psychomotor agitation,diurnal variation,obsessive/compulsive disorder,hopelessness,self-abasedment and gastrointestinal symptoms were significantly higher in IBS-C patients than that in FC patients(P<0.05).For IBS-C(χ^(2)=5.438,P<0.05)but not FC,patients with normal colon transit time were significantly more likely to have anxiety than those with slow colon transit time.For IBS-C patients but not FC patients,the threshold of first constant sensation,desire to defecate and sustained urgency were all weakly correlated with the degree of anxiety(r=0.414,r=0.404,and r=0.418,respectively,P<0.05).The proportion of patients with a low threshold of desire to defecate among IBS-C patients with depression was lower than that in those without depression(69.6%vs 41.9%,χ2=4.054,P<0.05).CONCLUSION Our findings highlight both overlapping and distinctive patterns of colon transit,dyssynergic patterns,anorectal sensation,psychological distress,and associations of psychiatric and colorectal motility characteristics in FC and IBS-C patients in an Eastern Chinese population,providing valuable insights into the pathophysiological underpinnings of these disorders. 展开更多
关键词 Functional constipation Constipation-predominant irritable bowel syndrome High-resolution anorectal manometry Colonic transmit test ANXIETY Depression
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NOMA with Adaptive Transmit Power Using Intelligent Reflecting Surfaces
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作者 Raed Alhamad Hatem Boujemaa 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期2059-2070,共12页
In this article,we use Intelligent Reflecting Surfaces(IRS)to improve the throughput of Non Orthogonal Multiple Access(NOMA)with Adaptive Transmit Power(ATP).The results are valid for Cognitive Radio Networks(CRN)wher... In this article,we use Intelligent Reflecting Surfaces(IRS)to improve the throughput of Non Orthogonal Multiple Access(NOMA)with Adaptive Transmit Power(ATP).The results are valid for Cognitive Radio Networks(CRN)where secondary source adapts its power to generate low interference at primary receiver.In all previous studies,IRS were implemented with fixed transmit power and previous results are not valid when the power of the secondary source is adaptive.In CRN,secondary nodes are allowed to transmit over the same band as primary users since they adapt their power to minimize the generated interference.Each NOMA user has a subset of dedicated reflectors.At any NOMA user,all IRS reflections have the same phase.CRN-NOMA using IRS offers 7,13,20 dB gain vs.CRN-NOMAwithout IRS for N=8,16,32 reflectors.We also evaluate the effects of primary interference.The results are valid for any number of NOMA users,Quadrature Amplitude Modulation(QAM)and Rayleigh channels. 展开更多
关键词 IRS 6G CRN NOMA adaptive transmit power(ATP)
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PSO-DBNet for Peak-to-Average Power Ratio Reduction Using Deep Belief Network
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作者 A.Jameer Basha M.Ramya Devi +3 位作者 S.Lokesh P.Sivaranjani D.Mansoor Hussain Venkat Padhy 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1483-1493,共11页
Data transmission through a wireless network has faced various signal problems in the past decades.The orthogonal frequency division multiplexing(OFDM)technique is widely accepted in multiple data transfer patterns at... Data transmission through a wireless network has faced various signal problems in the past decades.The orthogonal frequency division multiplexing(OFDM)technique is widely accepted in multiple data transfer patterns at various frequency bands.A recent wireless communication network uses OFDM in longterm evolution(LTE)and 5G,among others.The main problem faced by 5G wireless OFDM is distortion of transmission signals in the network.This transmission loss is called peak-to-average power ratio(PAPR).This wireless signal distortion can be reduced using various techniques.This study uses machine learning-based algorithm to solve the problem of PAPR in 5G wireless communication.Partial transmit sequence(PTS)helps in the fast transfer of data in wireless LTE.PTS is merged with deep belief neural network(DBNet)for the efficient processing of signals in wireless 5G networks.Result indicates that the proposed system outperforms other existing techniques.Therefore,PAPR reduction in OFDM by DBNet is optimized with the help of an evolutionary algorithm called particle swarm optimization.Hence,the specified design supports in improving the proposed PAPR reduction architecture. 展开更多
关键词 5G wireless network orthogonal frequency division multiplexing signal distortion peak to average power ratio partial transmit sequence deep belief network
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Misdiagnosis of Sexually Transmitted Diseases in Hong Kong Outpatient Private Healthcare
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作者 Andes Lau David W. Y. Ho 《Open Journal of Medical Microbiology》 CAS 2023年第1期31-42,共12页
Background and objective: Early and accurate diagnosis is one of the critical requirements for successful management of all diseases. Yet, delayed diagnosis and misdiagnosis remain as vital problems, consequently impo... Background and objective: Early and accurate diagnosis is one of the critical requirements for successful management of all diseases. Yet, delayed diagnosis and misdiagnosis remain as vital problems, consequently impose adverse effects on patient treatment. Sexually transmitted disease (STD) is one of the most common infectious diseases, and more than one million of STD cases are acquired every day globally. Misdiagnosis of STD inevitably exists, therefore should not be overlooked. Being a medical diagnostic laboratory providing various STDs diagnosing service in Hong Kong, we aimed to determine the misdiagnosis rate of STDs and investigate the possible underlying cause. Methods: Specimens were collected for STD diagnosis from multiple clinics during 1 June 2021 to 20 October 2021 from different clinics and hospitals were included in the study. DNA extraction was performed using magnetic bead based method;then the extracted DNA was tested using the DiagCor GenoFlow<sup>TM</sup> STD Array kit to detect the existence of any targeted pathogens. Results: 1459 specimens were collected and included during the designated time period, with 643 specimens found to be positive with at least one targeted STD pathogen. 494 of these were found to be aligned with test ordered by physicians, and the remaining 149 positive cases had at least one pathogen detected but not requested to be tested by the physicians resulting in misdiagnosis. The overall misdiagnosis rate was determined to be 23.2% (149/643), with high frequency of misdiagnosis occurred to tests ordered for one to three pathogens detection. Also, Ureaplasma urealyticum and/or Ureaplasma parvum (UU/UP) was the commonest pathogen detected in this study. Conclusion: The findings suggested incorrect test selection made by physicians was one of the major reasons of STDs misdiagnosis in outpatient settings. To reduce diagnostic errors in STD diagnosis, physicians are encouraged to select and request test that allow detection of multiple pathogens, as co-infection of multiple pathogens in STD patients is commonly observed. The correct selection of test would not only benefit the patient, but also the public health. 展开更多
关键词 Sexually Transmitted Diseases (STDs) Diagnostic Error MISDIAGNOSIS Incorrect Decision
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复杂外圆轮廓车铣复合编程
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作者 徐璐 金磊 +1 位作者 张利好 罗志明 《金属加工(冷加工)》 2023年第5期82-86,共5页
西门子数控系统提供了一种端面转换(TRANSMIT)和柱面转换(TRACYL)的方法,大大降低了车铣复合铣削的编程难度。以实例说明如何采用西门子数控系统的SinuTrain软件对复杂外圆轮廓零件进行车铣复合编程。
关键词 车铣外圆轮廓 端面转换 TRANSMIT 柱面转换 TRACYL
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Narrowband interference suppression in TR-UWB system based on cognitive radio theory 被引量:2
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作者 赵华 殷奎喜 邵建华 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期272-275,共4页
A cognitive radio transmitted reference ultra-wideband(CR-TR-UWB) system is proposed to improve the performance of TR-UWB systems with narrowband interference(NBI) from primary users(PU).The transmitter of the C... A cognitive radio transmitted reference ultra-wideband(CR-TR-UWB) system is proposed to improve the performance of TR-UWB systems with narrowband interference(NBI) from primary users(PU).The transmitter of the CR-TR-UWB system detects the band of PU,and then sends prolate spheroidal wave functions(PSWF) pulses with the same limited band as PU's to reduce interference with PU.The receiver uses a notch filter before autocorrelation to eliminate NBI from PU.The simulation results show that the bit error rate(BER) performance of the CR-TR-UWB system is close to that of TR-UWB systems without NBI when the system is interfered by single or double NBIs with a signal to interference ratio(SIR) of 0 dB,and if the signal to noise ratio(SNR) is 10 dB and the SIR varies from-20 to 10 dB,BER performance varies no more than an order of magnitude.The system has excellent resistance to NBI,strong robustness BER performance at different SNRs,and smaller interference with the same frequency band PU. 展开更多
关键词 transmitted reference ultra-wideband(TR-UWB) cognitive radio narrowband interference prolate spheroidal wave function(PSWF) coexistence communication
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MIMO-OFDM系统中联合时域和空间域信号处理的改进PTS算法 被引量:1
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作者 杨霖 胡武君 何向东 《系统工程与电子技术》 EI CSCD 北大核心 2014年第12期2526-2532,共7页
为了降低多输入多输出正交频分复用(multiple input multiple output orthogonal frequency division multiplexing,MIMO-OFDM)系统中传统部分传输序列(partial transmit sequence,PTS)算法的计算复杂度,提出了联合时域和空间域信号处... 为了降低多输入多输出正交频分复用(multiple input multiple output orthogonal frequency division multiplexing,MIMO-OFDM)系统中传统部分传输序列(partial transmit sequence,PTS)算法的计算复杂度,提出了联合时域和空间域信号处理的改进PTS算法。在时域信号处理部分,通过信号子块循环移位实现备选序列的增加;在空间域部分,利用天线间信号子块交换实现峰均功率比(peak to average power ratio,PAPR)抑制。同时在接收端,利用子块相位旋转引起的相位差异,本方法通过比较接收信号与星座点的距离,可以实现信号的盲检测,从而有效提高MIMO-OFDM系统的频谱利用率。仿真结果表明,提出的方法能有效地抑制MIMO-OFDM信号的PAPR,而且明显降低了传统PTS算法的计算复杂度,同时可获得跟传统PTS方法已知边带副信息时相似的比特误码率(bit error rate,BER)性能。 展开更多
关键词 部分传输序列 循环移位 交换 盲检测 PARTIAL transmit sequence (PTS)
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Partial transmitting sequence method based on trellis factor search 被引量:2
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作者 吴炳洋 程时昕 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期123-126,共4页
To obtain good trade-offs between complexity and performance onpeak-to-average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM)using partial transmitting sequence (PTS) schemes, a trel... To obtain good trade-offs between complexity and performance onpeak-to-average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM)using partial transmitting sequence (PTS) schemes, a trellis structure based PTS factor searchmethod is proposed. The trellis search is with a variant constraint length L_C, 1 ≤ L_C ≤ V-1,where V is the number of PTS subblocks. The method is to decide a PTS factor by searching all thepossible paths obtained by varying L_C consecutive factors. The trellis search can be viewed as ageneral PTS factor search model. If L_C = V-1, it is a full search, and if L_C = 1, it is aniterative search. Using different constraint lengths, trellis factor search PTS exhibits differentPAPR reduction performances. A larger L_C results in a better performance and L_C = V-1 results inthe optimum. However, a larger L_C requires more computation. This helps to choose a good trade-offbetween complexity and performance. 展开更多
关键词 peak-to-average power ratio (PAPR) partial transmitting sequence (PTS) trellis search
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Ray path of head waves with irregular interfaces 被引量:1
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作者 周红 陈晓非 《Applied Geophysics》 SCIE CSCD 2010年第1期66-73,100,共9页
Head waves are usually considered to be the refracted waves propagating along flat interfaces with an underlying higher velocity.However,the path that the rays travel along in media with irregular interfaces is not cl... Head waves are usually considered to be the refracted waves propagating along flat interfaces with an underlying higher velocity.However,the path that the rays travel along in media with irregular interfaces is not clear.Here we study the problem by simulation using a new approach of the spectral-element method with some overlapped elements(SEMO) that can accurately evaluate waves traveling along an irregular interface.Consequently,the head waves are separated from interface waves by a time window.Thus,their energy and arrival time changes can be analyzed independently.These analyses demonstrate that,contrary to the case for head waves propagating along a flat interface,there are two mechanisms for head waves traveling along an irregular interface:a refraction mechanism and transmission mechanism.That is,the head waves may be refracted waves propagating along the interface or transmitted waves induced by the waves propagating in the higher-velocity media.Such knowledge will be helpful in constructing a more accurate inversion method,such as head wave travel-time tomography,and in obtaining a more accurate model of subsurface structure which is very important for understanding the formation mechanism of some special areas,such as the Tibetan Plateau. 展开更多
关键词 head waves irregular interface refracted waves transmitted waves ray path
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FINITE ELEMENT-ARTIFICIAL TRANSMITTING BOUNDARY METHOD FOR WAVE SCATTERING FROM IRREGULAR CYLINDER 被引量:1
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作者 杨吉生 徐立军 +1 位作者 邢昌玉 杨光 《Transactions of Tianjin University》 EI CAS 1997年第2期36-39,共4页
The finite element artificial transmitting boundary method is employed here to treat the near field scattering of a cylindrical wave from an irregular cylinder. A comparison is made between this method and the analy... The finite element artificial transmitting boundary method is employed here to treat the near field scattering of a cylindrical wave from an irregular cylinder. A comparison is made between this method and the analytical one. And then examples are given to demonstrate the solution of several problems of the irregular object scattering. The method can not only produce clear physical pictures, but can efficiently handle many complicated scattering problems. 展开更多
关键词 finite elements artificial transmitting boundary SCATTERING
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LTE系统中采用SGA-PTS技术降低OFDM峰均比的研究与仿真 被引量:1
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作者 杨桂芹 赵春和 蒋占军 《铁道学报》 EI CAS CSCD 北大核心 2014年第4期38-41,共4页
LTE系统以OFDM技术为核心,但OFDM技术自身存在高峰均比的问题。随着硬件技术的迅速发展,概率类技术被认为是最有希望解决OFDM系统峰均比PAPR问题的一类方法。部分传输序列PTS(Partial Transmit Sequence)技术作为概率类技术中的代表技... LTE系统以OFDM技术为核心,但OFDM技术自身存在高峰均比的问题。随着硬件技术的迅速发展,概率类技术被认为是最有希望解决OFDM系统峰均比PAPR问题的一类方法。部分传输序列PTS(Partial Transmit Sequence)技术作为概率类技术中的代表技术一直广受关注,其关键问题在于搜索到合适的相位因子序列,使OFDM信号的峰均比性能最好。本文将混合的模拟退火遗传算法SGA(Simulated Annealing Genetic Algorithm)应用于PTS技术中相位因子序列的搜索,并通过仿真验证其有效性及优越性。对于相同的峰均比阈值要求,SGA算法能更好地改善PTS技术搜索最优相位因子序列的复杂度问题,使其更易于实现。 展开更多
关键词 LTE系统 模拟退火遗传算法 部分传输序列 峰均比 SGA (simulated annealing genetic algorithm ) PTS (partial transmit sequence) PAPR(peak-to-average power ratio)
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