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三维薛定谔方程组的线性Profile分解
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作者 韩依洋 廖梦兰 《湘潭大学学报(自然科学版)》 CAS 2024年第2期44-49,共6页
为了研究线性薛定谔方程组解Strichartz估计的紧性缺失问题,针对H•^(1)(R^(3))×H•^(1)(R^(3))中的三维线性薛定谔方程组的有界解向量序列,使用解序列的Profile分解方法,构造为解向量子列的(1/√h_(n))U(t-t_(n))/h_(n)^(2),(x-x_(n... 为了研究线性薛定谔方程组解Strichartz估计的紧性缺失问题,针对H•^(1)(R^(3))×H•^(1)(R^(3))中的三维线性薛定谔方程组的有界解向量序列,使用解序列的Profile分解方法,构造为解向量子列的(1/√h_(n))U(t-t_(n))/h_(n)^(2),(x-x_(n))/h_(n)类型的Profile分解和.其中,U是线性薛定谔方程组的解向量,在Strichartz范数估计下具有一个很小的余项.首先确定伸缩变换参数序列族,利用傅里叶变换和迭代的思想确定Profile分解族.其次验证了Profile分解和的收敛性,说明了Strichartz范数下余项的收敛性.最后证明了当线性薛定谔方程组的解序列有界时,都可以分解为解向量子列和的形式. 展开更多
关键词 薛定谔方程组 profile分解 STRICHARTZ估计 Sobolev嵌入 傅里叶变换
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Three-Channel Interference Interpretation of Fano Profile
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作者 李波 李天钧 +3 位作者 马子茹 王希源 黄新朝 朱林繁 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第5期30-34,共5页
Fano resonance is a ubiquitous phenomenon, and it is commonly interpreted as a two-channel interference of the discrete and continuous channels. The present work investigates the Fano profile from a perspective of the... Fano resonance is a ubiquitous phenomenon, and it is commonly interpreted as a two-channel interference of the discrete and continuous channels. The present work investigates the Fano profile from a perspective of the temporal evolution of the wave function. By exciting the atom with a δ pulse and calculating the evolution of the wave function, the Fano formula is deduced. The results clearly show that the Fano resonance is of a three-channel interference, which is different from the traditional understanding. The three channels are revealed as the groundcontinuum, ground-discrete-continuum, and a previously unmentioned third channel, i.e., ground-continuumdiscrete-continuum. The present three-channel interpretation can be easily generalized to other physical systems,contributing to a deeper understanding of the Fano profile. 展开更多
关键词 FUNCTION profile CONTINUUM
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Comprehensive evaluation and spatial-temporal evolution characteristics of urban resilience in Chengdu-Chongqing Economic Circle
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作者 Xin Li Shuyi Zhang +1 位作者 Rongxi Ren Yafei Wang 《Chinese Journal of Population,Resources and Environment》 2024年第1期58-67,共10页
To clarify the connotations and extensions of urban resilience,this study focuses on the Chengdu-Chongqing Economic Circle with 16 cities as research subjects.A comprehensive evaluation index system was constructed to... To clarify the connotations and extensions of urban resilience,this study focuses on the Chengdu-Chongqing Economic Circle with 16 cities as research subjects.A comprehensive evaluation index system was constructed to measure the resilience of each city from 2003 to 2020.The spatial-temporal evolution characteristics were analyzed using Kernel density estimation,standard deviation ellipse,and spatial Markov chain analysis,and the spatial Tobit model was introduced to discover the influencing factors.The results indicate the following:①Urban resilience in the Chengdu-Chongqing Economic Circle displays an upward trend,with the center of gravity moving to the southwest,and the polarization phenomenon intensifying.②The urban resilience level in a region has certain spatial and geographical dependence,while the probability of urban resilience transfer differs in adjacent cities with different resilience levels.③Urban centrality,economic scale,openness level,and financial development promote urban resilience,whereas government scale significantly inhibits it.Finally,this paper proposes countermeasures and suggestions to improve the urban resilience of the Chengdu-Chongqing Economic Circle. 展开更多
关键词 Chengdu-chongqing Economic Circle Urban resilience spatial-temporal evolution Driving factor
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Profile of Full-Term Births in Maternity Wards of Public Hospitals in Douala Cameroon
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作者 Henri Essome Merlin Boten Bounyom +14 位作者 Astrid Ndolo Kondo Ingrid Doriane Ofakem Ilick Fulbert Mangala Nkwele Irène Cyrielle Edjoa Mboe Michel Roger Ekono Alphonse Ngalame Nyong Robert Tchounzou Moustapha Bilkissou Junie Ngaha Yaneu Marga Vanina Ngono Akam Gervais Mounchikpou Ngouhouo Grâce Tocki Toutou Théophile Nana Njamen Valère Mve Koh Pascal Foumane 《Open Journal of Obstetrics and Gynecology》 2024年第5期705-720,共16页
Introduction: Pregnancy as much as childbirth constitutes a risky situation, potentially fraught with sometimes dramatic complications: maternal death. Objective: We conducted this study with the aim of establishing t... Introduction: Pregnancy as much as childbirth constitutes a risky situation, potentially fraught with sometimes dramatic complications: maternal death. Objective: We conducted this study with the aim of establishing the profile of those giving birth in our context with the aim to anticipate operationally in the future on morbidity but more on maternal deaths. Methodology: We conducted, using a structured questionnaire, a prospective descriptive study in representative maternity wards in the city of Douala;the study variables were socio-economic, anthropometric, obstetrical and clinical. Statistical analyses were carried out with CS Pro 7.3 and SPSS version 25.0 software. The Student, Chi-square and Fischer tests were used to compare the means of the variables and the percentages. Results: We recruited 305 births for our study. The average age of our births was 28.7 years ± 6.1 with an average height of 161.6 cm ± 5.06;an average body mass index at the start of pregnancy of 28.0 kilograms/square meter and 31.3 kilograms/square meter at delivery;the average weight gain was 8.4 g ± 5.37;an average gestation of 2.84±1.90;an average parity of 2.2 ± 2.1 with an average birth interval of 27.7 months ± 23.7. The average gestational age was 39.2 weeks ± 1.21 with pregnancy pathology dominated by malaria;85.9% began their prenatal follow-up before the 14th week of amenorrhea. Conclusion: The profile of childbirth in urban Cameroon does not seem potentially dystocic compared to that of the same regional and racial area. 展开更多
关键词 profile Delivery TERM MALARIA Douala
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Immunovirological Profile of HIV1 Infection in Children and Adolescents Followed at the Bangui Pediatric University Hospital
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作者 Simplice Cyriaque Kango Synthia Ningatoloum Nazita +3 位作者 Marie Colette Nganda-Bangue Michaël Dan-Houron Alexandre Manirakiza Jean Chrysostome Gody 《Open Journal of Pediatrics》 2024年第3期585-597,共13页
History: Pediatric management of HIV infection in children in the Central African Republic began in 2004 with the use of fractionated adult antiretrovirals and Cotrimoxazole. It has evolved over the years with the use... History: Pediatric management of HIV infection in children in the Central African Republic began in 2004 with the use of fractionated adult antiretrovirals and Cotrimoxazole. It has evolved over the years with the use of pediatric forms, oral suspensions and dispersible tablets. The transition to Dolutegravir took place in 2020. The active file of our patients will grow from 78 to over 1900 today. Follow-up examinations are carried out to assess adherence to treatment. Objective: To determine the immunovirological profile and factors associated with treatment failure during follow-up of children on ART at the Bangui pediatric university hospital. Patients and Method: This was a cross-sectional, analytical study from May 30 to December 02, 2022. The study sample was drawn from a cohort of HIV-1-infected children followed up at the Bangui pediatric university hospital and on ART for three semesters who met the selection criteria. Results: The prevalence of treatment failure varied from one semester to the next. Thus, the prevalence of therapeutic failure was 20% in the first semester, 10% in the second semester and 7% in the third semester. The prevalence of virological failure was 10.28% in the first half of the year, 6.91% in the second half and 4.98% in the third. Secondly, immunological failure was 0.48% in the first half of the year, 0.32% in the second 0.64% in the third half. Finally, clinical failure was 8.82% in the first half, 4.82% in the second half, 1.92% in the third half. Socio-demographic and clinical factors associated with treatment failure were male gender (p 1000 copies/ml (p Conclusion: The occurrence of treatment failures in children is a major problem, especially in our resource-limited countries, given the challenges facing antiretroviral therapy. It is therefore necessary to carry out a study on resistance genotyping in order to propose correct management protocols, as the future of treatment programs depends on it. 展开更多
关键词 profile Immunovirological HIV/AIDS CHILDREN Bangui
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TP-PROFILE: Monitoring the Thermodynamic Structure of the Troposphere over the Third Pole
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作者 Xuelong CHEN Yajing LIU +6 位作者 Yaoming MA Weiqiang MA Xiangde XU Xinghong CHENG Luhan LI Xin XU Binbin WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1264-1277,共14页
Ground-based microwave radiometers(MWRs)operating in the K-and V-bands(20–60 GHz)can help us obtain temperature and humidity profiles in the troposphere.Aside from some soundings from local meteorological observatori... Ground-based microwave radiometers(MWRs)operating in the K-and V-bands(20–60 GHz)can help us obtain temperature and humidity profiles in the troposphere.Aside from some soundings from local meteorological observatories,the tropospheric atmosphere over the Tibetan Plateau(TP)has never been continuously observed.As part of the Chinese Second Tibetan Plateau Scientific Expedition and Research Program(STEP),the Tibetan Plateau Atmospheric Profile(TPPROFILE)project aims to construct a comprehensive MWR troposphere observation network to study the synoptic processes and environmental changes on the TP.This initiative has collected three years of data from the MWR network.This paper introduces the data information,the data quality,and data downloading.Some applications of the data obtained from these MWRs were also demonstrated.Our comparisons of MWR against the nearest radiosonde observation demonstrate that the TP-PROFILE MWR system is adequate for monitoring the thermal and moisture variability of the troposphere over the TP.The continuous temperature and moisture profiles derived from the MWR data provide a unique perspective on the evolution of the thermodynamic structure associated with the heating of the TP.The TP-PROFILE project reveals that the low-temporal resolution instruments are prone to large uncertainties in their vapor estimation in the mountain valleys on the TP. 展开更多
关键词 microwave radiometer thermodynamic structure vertical profile Tibetan Plateau
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Neurocognitive Profile of People Living with Human Immunodeficiency Virus Initiating Treatment in Kinshasa in the Dolutegravir Era, Democratic Republic of Congo
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作者 Candide About Kabamba Berry Ikolango Bongenya +10 位作者 Jocelyn Ewuti Nonga Lambert Omombo Losenga Noëlla Maketi Dikati Thérèse Kasaka Ntumba Grace Ipaya Booto Rosalie Djamba Dembo Stéphanie Mauwa Selenge Benoit Obel Kabengele Guy Makila Mabe Bumoko Marie-Thérèse Ayane Safi Sombo Erick Ntambwe Kamangu 《Neuroscience & Medicine》 2024年第1期1-22,共22页
Context: Antiretroviral therapies improve the prognosis of NeuroAIDS contrasting with a high frequency of Minor Neurocognitive Disorders (MND) even in aviremic subjects. Objective: The objective of this study is to pr... Context: Antiretroviral therapies improve the prognosis of NeuroAIDS contrasting with a high frequency of Minor Neurocognitive Disorders (MND) even in aviremic subjects. Objective: The objective of this study is to present the neurological and cognitive profile of People Living with HIV (PLHIV) initiating antiretroviral treatment in Kinshasa in the era of Dolutegravir (DTG). Methods: This is a multicenter, cross-sectional study with a descriptive aim carried out in 16 HIV Outpatient Treatment Centers (OTC) in Kinshasa from October 4, 2021 to February 15, 2022. The International HIV Dementia Scale (IHDS) correlated with the Activities of Daily Living (IADL) scale facilitated the categorization of NeuroCognitive Disorders (NCD) of PLHIV evaluated after carrying out a summary neurological examination. Results: Of the 96 patients recruited, 56.3% were women with a sex ratio of 0.68. The average age was 40.1 ± 12.1 years. The secondary education level was the majority at 64.6%. Malaria (44.8%) and tuberculosis (32.3%) were more common as opportunistic infections. They were alcoholics in (30.2%). Their history was heart disease (15.6%), high blood pressure (18.8%);drug abuse (10.4%). The IHDS score was light in 55.2% of cases. The correlation between IHDS/IADL watches asymptomatic neurocognitive impairments (ANI) in 77.1%, almost all of subjects are found with normal overall functioning (94.8%) and a disturbed neurological examination in 53.1% of cases with a predominance of motor impairments in 79.1%. Conclusion: In view of these results, early and systematic screening of NCD and associated factors remains necessary in our context. . 展开更多
关键词 IHDS Dolutegravir Initiation KINSHASA Neurological profile PLHIV
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An efficient physics-guided Bayesian framework for predicting ground settlement profile during excavations in clay
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作者 Cong Tang Shuyu He Wanhuan Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1411-1424,共14页
Recently,the application of Bayesian updating to predict excavation-induced deformation has proven successful and improved prediction accuracy significantly.However,updating the ground settlement profile,which is cruc... Recently,the application of Bayesian updating to predict excavation-induced deformation has proven successful and improved prediction accuracy significantly.However,updating the ground settlement profile,which is crucial for determining potential damage to nearby infrastructures,has received limited attention.To address this,this paper proposes a physics-guided simplified model combined with a Bayesian updating framework to accurately predict the ground settlement profile.The advantage of this model is that it eliminates the need for complex finite element modeling and makes the updating framework user-friendly.Furthermore,the model is physically interpretable,which can provide valuable references for construction adjustments.The effectiveness of the proposed method is demonstrated through two field case studies,showing that it can yield satisfactory predictions for the settlement profile. 展开更多
关键词 Bayesian updating EXCAVATIONS Ground settlement profile Simplified model UNCERTAINTY
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Multi-circular formation control with reinforced transient profiles for nonholonomic vehicles:A path-following framework
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作者 Jintao Zhang Xingling Shao +1 位作者 Wendong Zhang Zongyu Zuo 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期278-287,共10页
This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the fe... This article investigates a multi-circular path-following formation control with reinforced transient profiles for nonholonomic vehicles connected by a digraph.A multi-circular formation controller endowed with the feature of spatial-temporal decoupling is devised for a group of vehicles guided by a virtual leader evolving along an implicit path,which allows for a circumnavigation on multiple circles with an anticipant angular spacing.In addition,notice that it typically imposes a stringent time constraint on time-sensitive enclosing scenarios,hence an improved prescribed performance control(IPPC)using novel tighter behavior boundaries is presented to enhance transient capabilities with an ensured appointed-time convergence free from any overshoots.The significant merits are that coordinated circumnavigation along different circles can be realized via executing geometric and dynamic assignments independently with modified transient profiles.Furthermore,all variables existing in the entire system are analyzed to be convergent.Simulation and experimental results are provided to validate the utility of suggested solution. 展开更多
关键词 Multi-circular formation Reinforced transient profiles Nonholonomic vehicles Path following
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Kinetic equilibrium reconstruction with internal safety factor profile constraints on EAST tokamak
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作者 樊皓尘 李国强 +10 位作者 钱金平 张学习 邬潇河 储宇奇 朱翔 连辉 刘海庆 吕波 金仡飞 臧庆 黄佳 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期61-67,共7页
Reconstruction of plasma equilibrium plays an important role in the analysis and simulation of plasma experiments. The kinetic equilibrium reconstruction with pressure and edge current constraints has been employed on... Reconstruction of plasma equilibrium plays an important role in the analysis and simulation of plasma experiments. The kinetic equilibrium reconstruction with pressure and edge current constraints has been employed on EAST tokamak. However, the internal safety factor(q) profile is not accurate. This paper proposes a new way of incorporating q profile constraints into kinetic equilibrium reconstruction. The q profile is yielded from the Polarimeter Interferometer(POINT)reconstruction. Virtual probes containing information on q profile constraints are added to inputs of the kinetic equilibrium reconstruction program to obtain the final equilibrium. The new equilibrium produces a more accurate internal q profile. This improved method would help analyze EAST experiments. 展开更多
关键词 equilibrium reconstruction tokamak data analysis kinetic equilibrium q profile polarimeter-interferometer
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Radical Hysterectomy in Cervical Cancer: Patients’ Epidemiological and Clinical Profiles and Perioperative Outcome in Two Referral Hospitals in Cameroon
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作者 Théophile Njamen Nana Robert Tchounzou +16 位作者 Fulbert Nkwele Mangala Alphonse Ngalame Henri Essome Sedrick Tiokeng Sidonie Noa Ananga Andrew Tassang Humphry Tatah Neng Isaac Mboh Eyong Gaetan Andre Wambo Simo Felix Adolphe Elong Fidelia Kobenge Mbi Junior Cédric Nana Njamen Charlotte Tchente Nguefack Thomas Obinchemti Egbe Gregory Ekane Halle Emile Telesphore Mboudou Marcellin Ngowe Ngowe 《Open Journal of Obstetrics and Gynecology》 2024年第3期466-479,共14页
Background: Cervical cancer (CC) is one of the most frequent cancers and the leading cause of death from gynecological cancer in Low and middle income countries, Cameroon inclusive. Surgery is the primary treatment mo... Background: Cervical cancer (CC) is one of the most frequent cancers and the leading cause of death from gynecological cancer in Low and middle income countries, Cameroon inclusive. Surgery is the primary treatment modality when the disease is diagnosed at early stage. Radical hysterectomy in cervical cancer has not been evaluated in recent years in Cameroon. The purpose of this study is thus to evaluate the epidemiological and clinical features and short term outcomes of patients who underwent surgery. Patients and methods: This retrospective study was conducted at the Douala Gynaeco-obstetric and Pediatric Hospital and the Douala General Hospital. Cervical cancer patients who underwent Radical hysterectomy between January 2015 and December 2020 were included. A pre-established data collection tool was used to record socio-demographic, clinical and outcomes information from patients’ files;additional outcome information was obtained from phone calls. Descriptive analysis was done using the SPSS version 26. Bivariate analysis was used to determine associations between disease and patients characteristics and occurrence of adverse postoperative outcome. P value of 0.05 was considered. Results: Sixty one patients were enrolled. Their ages ranged from 33 to 74 years with a mean age of 51.95 ± 10.29 years. Over 85% of women were married, 65.57% were unemployed and 86.88% were multiparous. Only 28% had never done cervical cancer screening. Most patients had stage IB1 to IB2 stage disease (57.1%). Less than 9% underwent radical hysterectomy and 8 of those (13.11%) suffered intraoperative complications. Twenty-five patients (40.98%) presented immediate and short term complications. There was no significant association between the disease or patients’ characteristics and adverse outcomes. Conclusion: Cervical cancer patients are relatively young in our settings and only 9% of them reach the hospital at early stage. Postoperative adverse outcomes rate is higher than that reported in the literature. Sensitization on screening and awareness of early symptoms can reverse the situation. 展开更多
关键词 Cervical Cancer Radical Hysterectomy Epidemiological and Clinical profiles OUTCOMES Cameroon
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Profiles of the Headspace Volatile Organic and Essential Oil Compounds from the Tunisian Cardaria draba (L.) Desv. and Its Leaf and Stem Epidermal Micromorphology
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作者 Wissal Saadellaoui Samiha Kahlaoui +6 位作者 Kheiria Hcini Abir Haddada Noomene Sleimi Roberta Ascrizzi Guido Flamini Fethia Harzallah-Skhiri Sondes Stambouli-Essassi 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期725-744,共20页
In this work, we investigated aroma volatiles emanated by dry roots, stems, leaves, flowers, and fruits of Cardariadraba (L.) Desv. growing wild in Tunisia and its aerial part essential oils (EOs) composition. A total... In this work, we investigated aroma volatiles emanated by dry roots, stems, leaves, flowers, and fruits of Cardariadraba (L.) Desv. growing wild in Tunisia and its aerial part essential oils (EOs) composition. A total of 37 volatileorganic compounds (96.7%–98.9%) were identified;4 esters, 4 alcohols, 7 hydrocarbons, 12 aldehydes, 5 ketones,1 lactone, 1 organosulfur compound, 2 organonitrogen compounds, and 1 acid. The hydrocarbons form the maingroup, representing 49.5%–84.6% of the total detected volatiles. The main constituent was 2,2,4,6,6-pentamethylheptane(44.5%–76.2%) reaching the highest relative percentages. Forty-two compounds were determined in thetwo fractions of EOs, representing 98.8% and 97.2% of the total oil composition, respectively. The principal componentswere hexadecanoic acid (34.6%), 6-methyl-5-hepten-2-one (18.3%), decanal (15.0%), 6,10,14-trimethyl-2-pentadecanone (13.2%), and n-pentacosane (13%). Micromorphological details of the leaf and stem epidermisusing light microscopy revealed polygonal cells with sinuous walls in the adaxial and abaxial leaf surfaces andnearly rectangular and long ones with linear and thick walls for the stem epidermis. The stomata complexes wereanisocytic in the leaf epidermis and mainly anisocytic and rarely paracytic in the stem epidermis. Non-glandulartrichomes were unbranched and long with an acute apex or short with a convex apex. The glandular ones wereidentified for the first time in this species. They were short-stalked with a large secretory head. The highest stomatalindex (17.02%) was recorded in the abaxial leaf surface. The identification of headspace volatiles and essentialoil compounds can be used to characterize this species, and the various epidermis micromorphologicalfeatures are very useful for biosystematics taxonomic studies within Brassicaceae. 展开更多
关键词 Cardaria draba aroma profile essential oils EPIDERMIS TRICHOMES
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Metabolic profiles and morphological characteristics of leaf tips among different sweet potato(Ipomoea batatas Lam.)varieties
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作者 Wenqing Tan Xinbo Guo +7 位作者 Zhangying Wang Rong Zhang Chaochen Tang Bingzhi Jiang Ruixue Jia Yuanyuan Deng Shaohai Yang Jingyi Chen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期494-510,共17页
Sweet potato leaf tips have high nutritional value,and exploring the differences in the metabolic profiles of leaf tips among different sweet potato varieties can provide information to improve their qualities.In this... Sweet potato leaf tips have high nutritional value,and exploring the differences in the metabolic profiles of leaf tips among different sweet potato varieties can provide information to improve their qualities.In this study,a UPLC-Q-Exactive Orbitrap/MS-based untargeted metabolomics method was used to evaluate the metabolites in leaf tips of 32 sweet potato varieties.Three varieties with distinct overall metabolic profiles(A01,A02,and A03),two varieties with distinct profiles of phenolic acids(A20 and A18),and three varieties with distinct profiles of flavonoids(A05,A12,and A16)were identified.In addition,a total of 163 and 29 differentially expressed metabolites correlated with the color and leaf shape of sweet potato leaf tips,respectively,were identified through morphological characterization.Group comparison analysis of the phenotypic traits and a metabolite-phenotypic trait correlation analysis indicated that the color differences of sweet potato leaf tips were markedly associated with flavonoids.Also,the level of polyphenols was correlated with the leaf shape of sweet potato leaf tips,with lobed leaf types having higher levels of polyphenols than the entire leaf types.The findings on the metabolic profiles and differentially expressed metabolites associated with the morphology of sweet potato leaf tips can provide useful information for breeding sweet potato varieties with higher nutritional value. 展开更多
关键词 sweet potato leaf tips phenotypic traits metabolic profile differentially expressed metabolites POLYPHENOLS
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Changes in the Non-targeted Metabolomic Profile of Three-year-old Toddlers with Elevated Exposure to Polycyclic Aromatic Hydrocarbons
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作者 LI Yang LIN Dan +7 位作者 ZHANG Xiu Qin JU Guang Xiu SU Ya ZHANG Qian DUAN Hai Ping YU Wei Sen WANG Bing Ling PANG Shu Tao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第5期479-493,共15页
Objective To investigate changes in the urinary metabolite profiles of children exposed to polycyclic aromatic hydrocarbons(PAHs)during critical brain development and explore their potential link with the intestinal m... Objective To investigate changes in the urinary metabolite profiles of children exposed to polycyclic aromatic hydrocarbons(PAHs)during critical brain development and explore their potential link with the intestinal microbiota.Methods Liquid chromatography-tandem mass spectrometry was used to determine ten hydroxyl metabolites of PAHs(OH-PAHs)in 36-month-old children.Subsequently,37 children were categorized into low-and high-exposure groups based on the sum of the ten OH-PAHs.Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to identify non-targeted metabolites in the urine samples.Furthermore,fecal flora abundance was assessed by 16S rRNA gene sequencing using Illumina MiSeq.Results The concentrations of 21 metabolites were significantly higher in the high exposure group than in the low exposure group(variable importance for projection>1,P<0.05).Most of these metabolites were positively correlated with the hydroxyl metabolites of naphthalene,fluorine,and phenanthrene(r=0.336–0.531).The identified differential metabolites primarily belonged to pathways associated with inflammation or proinflammatory states,including amino acid,lipid,and nucleotide metabolism.Additionally,these distinct metabolites were significantly associated with specific intestinal flora abundances(r=0.34–0.55),which were mainly involved in neurodevelopment.Conclusion Higher PAH exposure in young children affected metabolic homeostasis,particularly that of certain gut microbiota-derived metabolites.Further investigation is needed to explore the potential influence of PAHs on the gut microbiota and their possible association with neurodevelopmental outcomes. 展开更多
关键词 Child Gut microbiota Non-targeted metabolomics Polycyclic aromatic hydrocarbons Urinary metabolite profile
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Effect of dates on blood glucose and lipid profile among patients with type 2 diabetes
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作者 Hyder Osman Mirghani 《World Journal of Diabetes》 SCIE 2024年第6期1079-1085,共7页
Poor fruit and vegetable consumption is one of the 10 major risk factors for mortality.There is a misconception regarding the consumption of dates among patients with diabetes.This manuscript assessed the effects of d... Poor fruit and vegetable consumption is one of the 10 major risk factors for mortality.There is a misconception regarding the consumption of dates among patients with diabetes.This manuscript assessed the effects of date consumption on fasting and postprandial blood glucose,glycated hemoglobin,total cholesterol,triglycerides,low-density lipoproteins,high-density lipoproteins,and microbial markers.Four literature databases were searched for relevant articles.Of the 595 studies retrieved,24 assessed the effects of dates on glycemic control and lipids.Overall,the evidence suggests that dates have a lowering effect on blood glucose.Dates reduce total cholesterol and triglyceride levels and increase high-density lipoprotein levels.Dates also promote the abundance of beneficial gut microbiota.Therefore,patients with diabetes and dyslipidemia can consume dates to reduce their blood glucose,cholesterol,and triglycerides. 展开更多
关键词 DATES Lipid profile Blood glucose Diabetes mellitus Microbial contamination
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Detection and analysis of serum bile acid profile in patients with colonic polyps
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作者 Xin Ji Hong Chen 《World Journal of Clinical Cases》 SCIE 2024年第13期2160-2172,共13页
BACKGROUND Analyzing the variations in serum bile acid(BA)profile can provide a certain biological basis for early warning and prevention of various diseases.There is currently no comprehensive study on the relationsh... BACKGROUND Analyzing the variations in serum bile acid(BA)profile can provide a certain biological basis for early warning and prevention of various diseases.There is currently no comprehensive study on the relationship between the serum BA profile and colonic polyps.AIM To study the serum BA profile detection results of patients with colonic polyps,and analyze the correlation between BA and colonic polyps.METHODS From January 1,2022,to June 1,2023,204 patients with colonic polyps who were diagnosed and treated at Zhongda Hospital Southeast University were chosen as the study subjects,and 135 non-polyp people who underwent physical examination were chosen as the control group.Gathering all patients'clinical information,typical biochemical indicators,and BA profile.RESULTS Compared with the control group,the serum levels of taurocholic acid,glycocholic acid,glycochenodeoxycholic acid,and taurochenodeoxycholic acid in the colonic polyp group were significantly higher than those in the control group,while the content of deoxycholic acid(DCA)was lower than that in the control group(P<0.05).When colonic polyps were analyzed as subgroups,it was shown that there was a strong correlation between changes in the BA profile and polyp diameter,location,morphology,pathological kind,etc.CONCLUSION The serum BA profile showed significant changes in patients with colonic polyps,with a significant increase in primary conjugated BA content and a decrease in secondary free bile acid DCA content.There is a certain correlation between primary free BA and pathological parameters of polyps. 展开更多
关键词 SERUM Bile acid profile Colonic polyps Bile acid metabolism
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Experimental study of core MHD behavior and a novel algorithm for rational surface detection based on profile reflectometry in EAST
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作者 叶凯萱 周振 +20 位作者 张涛 马九阳 王嵎民 李恭顺 耿康宁 吴茗甫 文斐 黄佳 张洋 邵林明 杨书琪 钟富彬 高善露 喻琳 周子强 向皓明 韩翔 张寿彪 李国强 高翔 the EAST Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期66-75,共10页
Microwave reflectometry is a powerful diagnostic that can measure the density profile and localized turbulence with high spatial and temporal resolution and will be used in ITER,so understanding the influence of plasm... Microwave reflectometry is a powerful diagnostic that can measure the density profile and localized turbulence with high spatial and temporal resolution and will be used in ITER,so understanding the influence of plasma perturbations on the reflect signal is important.The characteristics of the reflect signal from profile reflectometry,the time-of-flight(TOF)signal associated with the MHD instabilities,are investigated in EAST.Using a 1D full-wave simulation code by the Finite-DifferenceTime-Domain(FDTD)method,it is well validated that the local density flattening could induce the discontinuity of the simulated TOF signal and an obvious change of reflect amplitude.Experimental TOF signals under different types of MHD instabilities(sawtooth,sawtooth precursors and tearing mode)are studied in detail and show agreement with the simulation.Two new improved algorithms for detecting and localizing the radial positions of the low-order rational surface,the cross-correlation and gradient threshold(CGT)method and the 2D convolutional neural network approach(CNN)are presented for the first time.It is concluded that TOF signal analysis from profile reflectometry can provide a straightforward and localized measurement of the plasma perturbation from the edge to the core simultaneously and may be a complement or correction to the q-profile control,which will be beneficial for the advanced tokamak operation. 展开更多
关键词 MHD instabilities profile reflectometry rational surface detection convolutional neural network(CNN) EAST tokamak
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Spatial-temporal distribution and geochemistry of highly evolved Mesozoic granites in Great Xing’an Range,NE China:Discriminant criteria and geological significance
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作者 WU Haoran YANG Hao +4 位作者 GE Wenchun JI Zheng DONG Yu JING Yan JING Jiahao 《Global Geology》 2024年第1期20-34,共15页
Highly evolved granite is an important sign of the mature continent crust and closely associated with deposits of rare metals.In this work,the authors undertake systematically zircon U-Pb ages and whole rock elemental... Highly evolved granite is an important sign of the mature continent crust and closely associated with deposits of rare metals.In this work,the authors undertake systematically zircon U-Pb ages and whole rock elemental data for highly evolved granitic intrusions from the Great Xing’an Range(GXR),NE China,to elucidate their discriminant criteria,spatial-temporal distribution,differentiation and geodynamic mecha-nism.Geochemical data of these highly evolved granites suggest that high w(SiO_(2))(>70%)and differentiation index(DI>88)could be quantified indicators,while strong Eu depletion,high TE_(1,3),lowΣREE and low Zr/Hf,Nb/Ta,K/Rb could only be qualitative indicators.Zircon U-Pb ages suggest that the highly evolved gran-ites in the GXR were mainly formed in Late Mesozoic,which can be divided into two major stages:Late Ju-rassic-early Early Cretaceous(162-136 Ma,peak at 138 Ma),and late Early Cretaceous(136-106 Ma,peak at 126 Ma).The highly evolved granites are mainly distributed in the central-southern GXR,and display a weakly trend of getting younger from northwest to southeast,meanwhile indicating the metallogenic potential of rare metals within the central GXR.The spatial-temporal distribution,combined with regional geological data,indicates the highly evolved Mesozoic granites in the GXR were emplaced in an extensional environ-ment,of which the Late Jurassic-early Early Cretaceous extension was related to the closure of the Mongol-Okhotsk Ocean and roll-back of the Paleo-Pacific Plate,while the late Early Cretaceous extension was mainly related to the roll-back of the Paleo-Pacific Plate. 展开更多
关键词 highly evolved granite Great Xing’an Range spatial-temporal distribution extensional environment
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On the calibration of a shear stress criterion for rock joints to represent the full stress-strain profile
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作者 Akram Deiminiat Jonathan D.Aubertin Yannic Ethier 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期379-392,共14页
Conventional numerical solutions developed to describe the geomechanical behavior of rock interfaces subjected to differential load emphasize peak and residual shear strengths.The detailed analysis of preand post-peak... Conventional numerical solutions developed to describe the geomechanical behavior of rock interfaces subjected to differential load emphasize peak and residual shear strengths.The detailed analysis of preand post-peak shear stress-displacement behavior is central to various time-dependent and dynamic rock mechanic problems such as rockbursts and structural instabilities in highly stressed conditions.The complete stress-displacement surface(CSDS)model was developed to describe analytically the pre-and post-peak behavior of rock interfaces under differential loads.Original formulations of the CSDS model required extensive curve-fitting iterations which limited its practical applicability and transparent integration into engineering tools.The present work proposes modifications to the CSDS model aimed at developing a comprehensive and modern calibration protocol to describe the complete shear stressdisplacement behavior of rock interfaces under differential loads.The proposed update to the CSDS model incorporates the concept of mobilized shear strength to enhance the post-peak formulations.Barton’s concepts of joint roughness coefficient(JRC)and joint compressive strength(JCS)are incorporated to facilitate empirical estimations for peak shear stress and normal closure relations.Triaxial/uniaxial compression test and direct shear test results are used to validate the updated model and exemplify the proposed calibration method.The results illustrate that the revised model successfully predicts the post-peak and complete axial stressestrain and shear stressedisplacement curves for rock joints. 展开更多
关键词 Full shear profile Post-peak shear behavior Rock joint Joint roughness coefficient(JRC) Axial stress-strain curve
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Spatial-temporal Variation Characteristics of Water Quality in the Lower Reaches of the Nenjiang River
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作者 Xiangzhe MENG Jing WANG +4 位作者 Yinglin XIE Fei PENG Chunsheng WEI Xin TIAN Lunwen WANG 《Meteorological and Environmental Research》 2024年第1期67-71,共5页
As an important river in the western part of Jilin Province,the lower reach of the Nenjiang River is an important wetland water source conservation area in Jilin Province.Within the watershed,it governs the Momoge Wet... As an important river in the western part of Jilin Province,the lower reach of the Nenjiang River is an important wetland water source conservation area in Jilin Province.Within the watershed,it governs the Momoge Wetland,the Xianghai Wetland,and the Danjiang Wetland in Jilin Province.The main problem in the lower reaches of the Nenjiang River is the uneven distribution of water resources in time and space,and the intensification of land salinization.Zhenlai County and Da an City in the Nenjiang River Basin have sufficient surface water resources,with surface water as the drinking water source.Baicheng City and Tongyu County have scarce surface water resources,and both use groundwater as their domestic water source.The main polluted section in the basin is the Xianghai Reservoir,and the annual water quality evaluation is Class V.However,the water quality of the Tao er River,the main stream of the Nenjiang River,is significantly better than that of the Xianghai Reservoir.In order to better study the water environmental pollution situation in the Nenjiang River basin,monitoring data from five sections of non seasonal rivers in the basin from 2012 to 2021 were selected for studying water quality.This in-depth exploration of the water pollution status and river water quality change trends in the Nenjiang River basin is of great significance for future rural development,agricultural pattern transformation,and the promotion of water ecological civilization construction. 展开更多
关键词 Lower reaches of the Nenjiang River Water quality spatial-temporal variation
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