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Using neural network modeling to improve the detection accuracy of land subsidence due to groundwater withdrawal
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作者 Ali M.RAJABI Ali EDALAT +1 位作者 Yasaman ABOLGHASEMI Mahdi KHODAPARAST 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2320-2333,共14页
Despite the high efficiency of remote sensing methods for rapid and large-scale detection of subsidence phenomena,this technique has limitations such as atmospheric impact and temporal and spatial decorrelation that a... Despite the high efficiency of remote sensing methods for rapid and large-scale detection of subsidence phenomena,this technique has limitations such as atmospheric impact and temporal and spatial decorrelation that affect the accuracy of the results.This paper proposes a method based on an artificial neural network to improve the results of monitoring land subsidence due to groundwater overexploitation by radar interferometry in the Aliabad plain(Central Iran).In this regard,vertical ground deformations were monitored over 18 months using the Sentinel-1A SAR images.To model the land subsidence by a multilayer perceptron(MLP)artificial neural network,four parameters,including groundwater level,alluvial thickness,elastic modulus,and transmissivity have been applied.The model's generalizability was assessed using data derived for 144 days.According to the results,the neural network estimates the land subsidence at each ground point with an accuracy of 6.8 mm.A comparison between the predicted and actual values indicated a significant agreement.The MLP model can be used to improve the results of subsidence detection in the study area or other areas with similar characteristics. 展开更多
关键词 DINSAR Land subsidence Groundwater withdrawal Aliabad plain Artificial neural network
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Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope
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作者 Wei He Si-yuan Feng +4 位作者 Jian Zhang Hong-wu Tang Yang Xiao Sheng Chen Chun-sheng Liu 《Water Science and Engineering》 EI CAS CSCD 2024年第2期197-208,共12页
Lateral intakes are common in rivers.The pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division width.The hydraulic characteristics of lateral withdrawa... Lateral intakes are common in rivers.The pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division width.The hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be investigated.Meanwhile,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be clarified.Hence,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side bank.The flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel velocities.This study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this phenomenon.The average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank conditions.With a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical direction.Under inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope conditions.The results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains. 展开更多
关键词 Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OPENFOAM
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Discussion on Land Use Mode Reform in Coal Opencast Mining
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作者 Hong ZHANG Lin LIN 《Asian Agricultural Research》 2024年第1期25-28,共4页
The existing land supply mode of opencast mining is"land requisition first,then transfer",which lacks an effective recovery and withdrawal mechanism,and the reclaimed mining land is difficult to withdraw.Acc... The existing land supply mode of opencast mining is"land requisition first,then transfer",which lacks an effective recovery and withdrawal mechanism,and the reclaimed mining land is difficult to withdraw.According to the regular rules of coal opencast mining and the periodic characteristics of land use,this paper puts forward a new mode of temporary land use for coal opencast mining.It is conducive to im-proving the quality and scale of land use and reclamation utilization of opencast coal mining,and is of great significance for exploring and for-mulating reasonable land use policies for mineral resources development projects. 展开更多
关键词 Opencast mine Temporary land use Land requisition RECLAMATION Withdrawal mechanism
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A Problem Not to Be Ignored: The Influencing Factors of Mobile Phone Addiction and Its Influence on Sleep Quality
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作者 Zihan Ji Lian Zhou 《Health》 2024年第5期459-469,共11页
Background and Objective: With the popularity and widespread use of mobile phones, the effects of mobile phone dependence and addiction on individuals’ physical and mental health have attracted more and more attentio... Background and Objective: With the popularity and widespread use of mobile phones, the effects of mobile phone dependence and addiction on individuals’ physical and mental health have attracted more and more attention. The present study aims to analyze the current state of mobile phone addiction and its impact on sleep quality within the population, while also exploring the influence of related factors on sleep quality. Ultimately, this research will provide a scientific foundation for targeted intervention measures and strategies. Methods: A total of 253 permanent residents in Nanjing were randomly selected as study subjects. The Mobile Phone Addiction Index (MPAI) and Pittsburgh Sleep Quality Index (PSQI) were used to evaluate the degree of smartphone addiction and sleep quality of the study subjects. Body mass index (BMI) was measured according to standardized procedures. Independent sample t-test, Chi-square test, rank sum test and multiple linear regression were used to analyze the correlation between mobile phone addiction and sleep quality, and P Results: 117 people (46.2%) were addicted to mobile phones. Chi-square test showed that the rate of mobile phone addiction in drinking group was significantly higher than that in non-drinking group (P P P P P P P P P P Conclusion: Mobile phone addiction may lead to shorter sleep duration and reduce sleep efficiency. The withdrawal of mobile phone addiction may have a negative impact on sleep quality. According to the characteristics of the population, appropriate comprehensive intervention measures should be taken to build an effective evaluation system, so as to reduce the impact of mobile phone addiction and withdrawal problems on sleep and improve sleep quality. 展开更多
关键词 Mobile Phone Addiction Influencing Factors WITHDRAWAL Sleep Quality
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Dovish Candidate Withdraws
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《Beijing Review》 2006年第31期3-,共1页
Former Japanese Chief Cabinet Secretary Yasuo Fukuda formally announced on July 21 his withdrawal from the upcoming Liberal Democratic Party's (LDP) presidential election in September, citing his opposition to off... Former Japanese Chief Cabinet Secretary Yasuo Fukuda formally announced on July 21 his withdrawal from the upcoming Liberal Democratic Party's (LDP) presidential election in September, citing his opposition to officials' visits to the war-related Yasukuni Shrine and his advanced age. 展开更多
关键词 LDP Dovish Candidate withdraws
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CNOOC Withdraws Quotation for Unocal Purchase
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《China Chemical Reporter》 2005年第23期7-7,共1页
CNOOC Ltd.announced on Aug.3 thatit has withdrawn its quotation for thepurchase of Unocal.According to CNOOC Ltd.,thecompany proposed to purchase all thecirculating shares of Unocal in cashwith a total price of US$18.... CNOOC Ltd.announced on Aug.3 thatit has withdrawn its quotation for thepurchase of Unocal.According to CNOOC Ltd.,thecompany proposed to purchase all thecirculating shares of Unocal in cashwith a total price of US$18.5 billion.The company had a sufficient capitalguarantee and its quotation 展开更多
关键词 SHARES PURCHASE CHEVRON WITHDRAWAL seriously issued administration raising eliminated remove
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Exit strategies in inflammatory bowel disease:Looking beyond antitumor necrosis factors 被引量:1
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作者 Federica Crispino Andrea Michielan +4 位作者 Mauro Grova Chiara Tieppo Marta Mazza Teresa Marzia Rogger Franco Armelao 《World Journal of Clinical Cases》 SCIE 2023年第12期2657-2669,共13页
The long-term management of patients with inflammatory bowel disease(IBD)is still a matter of debate,and no clear guidelines have been issued.In clinical practice,gastroenterologists often have to deal with patients i... The long-term management of patients with inflammatory bowel disease(IBD)is still a matter of debate,and no clear guidelines have been issued.In clinical practice,gastroenterologists often have to deal with patients in prolonged remission after immunomodulatory or immunosuppressive therapies.When planning an exit strategy for drug withdrawal,the risk of disease relapse must be balanced against the risk of drug-related adverse events and healthcare costs.Furthermore,there is still a dearth of data on the withdrawal of novel biologics,such as the anti-α4β7 integrin antibody(vedolizumab)and anti-IL12/23 antibody(ustekinumab),as well as the small molecule tofacitinib.Models for estimating the risk of disease relapse and the efficacy of retreatment should be evaluated according to the patient's age and IBD phenotype.These models should guide clinicians in programming a temporary drug withdrawal after discussing realistic outcomes with the patient.This would shift the paradigm from an exit strategy to a holiday strategy. 展开更多
关键词 Exit strategy Biologic withdrawal Drug holiday Vedolizumab USTEKINUMAB Tofacitinib
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A case of phenibut withdrawal and treatment with baclofen
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作者 Michael Morris James Espinosa +1 位作者 Alan Lucerna Robin Lahr 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第4期338-340,共3页
Phenibut(β-phenyl-γ-aminobutyric acid)is a psychoactive gamma-aminobutyric acid(GABA)analog marketed online as a nutritional and nootropic(cognition enhancing)supplement.Phenibut consumption poses a high risk of pot... Phenibut(β-phenyl-γ-aminobutyric acid)is a psychoactive gamma-aminobutyric acid(GABA)analog marketed online as a nutritional and nootropic(cognition enhancing)supplement.Phenibut consumption poses a high risk of potential abuse.Withdrawal from phenibut mimics benzodiazepine and alcohol withdrawal and can be dangerous.A number of approaches have been described for phenibut withdrawal,including protocols that include baclofen,but for inpatient and outpatient use.Here we describe a 30-year-old male who presented to an emergency department(ED)with insomnia,anxiety and palpitations after he stopped taking phenibut. 展开更多
关键词 treatment WITHDRAWAL ALCOHOL
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Withdrawal Intention of Farmers from Vacant Rural Homesteads and Its Influencing Mechanism in Northeast China: A Case Study of Jilin Province
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作者 YU Jiaping LI Jing +1 位作者 LO Kevin HUANG Shanlin 《Chinese Geographical Science》 SCIE CSCD 2023年第4期634-648,共15页
The effective use of land in Northeast China is of great significance for ensuring national food security and regional rural revitalization.In this study,based on the survey data collected from Jilin Province,Northeas... The effective use of land in Northeast China is of great significance for ensuring national food security and regional rural revitalization.In this study,based on the survey data collected from Jilin Province,Northeast China,we analyzed the vacancy rates of rural homesteads in suburban,outer suburban,and remote villages,as well as the withdrawal intention of rural-settled farmers,urbansettled farmers,and farmers with urban and rural dual residency from vacant homesteads.From the perspective of farmers’perceptions,this study constructed a theoretical framework of the influence mechanism of their withdrawal intention and analyzed such mechanism by constructing a structural equation model.The results indicated that:1)rural homestead vacancy rates increased with distance from the village to the city.2)rural-settled farmers showed a low withdrawal intention for vacant rural homesteads,followed by urban and rural dual-residence farmers,and urban-settled farmers showed the highest withdrawal intention.3)the relative importance of the factors influencing withdrawal intention is in the following order:policy awareness>interest perception>living environment perception>family characteristics.Finally,this study discussed the reformation of the homestead system and rural homestead transition in Northeast China,which can provide policy support to increase the potential of cultivated land and promote sustainable rural development and urban-rural coordination. 展开更多
关键词 village hollowing vacant rural homesteads withdrawal intention influence mechanism Northeast China
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Improving polyp detection at colonoscopy: Non-technological techniques
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作者 Ragul Rajivan Sreedhari Thayalasekaran 《World Journal of Gastrointestinal Endoscopy》 2023年第5期354-367,共14页
Colonoscopy and polypectomy remain the gold standard investigation for the detection and prevention of colorectal cancer.Halting the progression of colonic adenoma through adequate detection of pre-cancerous lesions i... Colonoscopy and polypectomy remain the gold standard investigation for the detection and prevention of colorectal cancer.Halting the progression of colonic adenoma through adequate detection of pre-cancerous lesions interrupts the progression to carcinoma.The adenoma detection rate is a key performance indicator.Increasing adenoma detection rates are associated with reducing rates of interval colorectal cancer.Endoscopists with high baseline adenoma detection rate have a meticulous technique during colonoscopy withdrawal that improves their adenoma detection.This minireview article summarizes the evidence on the following simple operator techniques and their effects on the adenoma detection rate;minimum withdrawal times,dynamic patient position change and proximal colon retroflexion. 展开更多
关键词 COLONOSCOPY Minimum withdrawal times Dynamic position change Proximal colon retroflexion
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Clonidine use during dexmedetomidine weaning:A systematic review
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作者 Sanu Rajendraprasad Molly Wheeler +5 位作者 Erin Wieruszewski Joseph Gottwald Lindsey A.Wallace Danielle Gerberi Patrick M Wieruszewski Nathan J Smischney 《World Journal of Critical Care Medicine》 2023年第1期18-28,共11页
BACKGROUND Dexmedetomidine is a centrally acting alpha-2A adrenergic agonist that is commonly used as a sedative and anxiolytic in the intensive care unit(ICU),with prolonged use increasing risk of withdrawal symptoms... BACKGROUND Dexmedetomidine is a centrally acting alpha-2A adrenergic agonist that is commonly used as a sedative and anxiolytic in the intensive care unit(ICU),with prolonged use increasing risk of withdrawal symptoms upon sudden discontinuation.As clonidine is an enterally available alpha-2A adrenergic agonist,it may be a suitable agent to taper off dexmedetomidine and reduce withdrawal syndromes.The appropriate dosing and conversion strategies for using enteral clonidine in this context are not known.The objective of this systematic review is to summarize the evidence of enteral clonidine application during dexmedetomidine weaning for prevention of withdrawal symptoms.AIM To systematically review the practice,dosing schema,and outcomes of enteral clonidine use during dexmedetomidine weaning in critically ill adults.METHODS This was a systematic review of enteral clonidine used during dexmedetomidine weaning in critically ill adults(≥18 years).Randomized controlled trials,prospective cohorts,and retrospective cohorts evaluating the use of clonidine to wean patients from dexmedetomidine in the critically ill were included.The primary outcomes of interest were dosing and titration schema of enteral clonidine and dexmedetomidine and risk factors for dexmedetomidine withdrawal.Other secondary outcomes included prevalence of adverse events associated with enteral clonidine use,re-initiation of dexmedetomidine,duration of mechanical ventilation,and ICU length of stay.RESULTS A total of 3427 studies were screened for inclusion with three meeting inclusion criteria with a total of 88 patients.All three studies were observational,two being prospective and one retrospective.In all included studies,the choice to start enteral clonidine to wean off dexmedetomidine was made at the discretion of the physician.Weaning time ranged from 13 to 167 h on average.Enteral clonidine was started in the prospective studies in a similar protocolized method,with 0.3 mg every 6 h.After starting clonidine,patients remained on dexmedetomidine for a median of 1-28 h.Following the termination of dexmedetomidine,two trials tapered enteral clonidine by increasing the interval every 24 h from 6 h to 8h,12h,and 24 h,followed by clonidine discontinuation.For indicators of enteral clonidine withdrawal,the previously tolerable dosage was reinstated for several days before resuming the taper on the same protocol.The adverse events associated with enteral clonidine use were higher than patients on dexmedetomidine taper alone with increased agitation.The re-initiation of dexmedetomidine was not documented in any study.Only 17(37%)patients were mechanically ventilated with median duration of 3.5 d for 13 patients in one of the 2 studies.ICU lengths of stay were similar.CONCLUSION Enteral clonidine is a strategy to wean critically ill patients from dexmedetomidine.There is an association of increased withdrawal symptoms and agitation with the use of a clonidine taper. 展开更多
关键词 CLONIDINE DEXMEDETOMIDINE Intensive care unit WITHDRAWAL WEANING
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Artificial intelligence fails to improve colonoscopy quality:A single centre retrospective cohort study
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作者 Naeman Goetz Katherine Hanigan Richard Kai-Yuan Cheng 《Artificial Intelligence in Gastrointestinal Endoscopy》 2023年第2期18-26,共9页
BACKGROUND Limited data currently exists on the clinical utility of Artificial Intelligence Assisted Colonoscopy(AIAC)outside of clinical trials.AIM To evaluate the impact of AIAC on key markers of colonoscopy quality... BACKGROUND Limited data currently exists on the clinical utility of Artificial Intelligence Assisted Colonoscopy(AIAC)outside of clinical trials.AIM To evaluate the impact of AIAC on key markers of colonoscopy quality compared to conventional colonoscopy(CC).METHODS This single-centre retrospective observational cohort study included all patients undergoing colonoscopy at a secondary centre in Brisbane,Australia.CC outcomes between October 2021 and October 2022 were compared with AIAC outcomes after the introduction of the Olympus Endo-AID module from October 2022 to January 2023.Endoscopists who conducted over 50 procedures before and after AIAC introduction were included.Procedures for surveillance of inflammatory bowel disease were excluded.Patient demographics,proceduralist specialisation,indication for colonoscopy,and colonoscopy quality metrics were collected.Adenoma detection rate(ADR)and sessile serrated lesion detection rate(SSLDR)were calculated for both AIAC and CC.RESULTS The study included 746 AIAC procedures and 2162 CC procedures performed by seven endoscopists.Baseline patient demographics were similar,with median age of 60 years with a slight female predominance(52.1%).Procedure indications,bowel preparation quality,and caecal intubation rates were comparable between groups.AIAC had a slightly longer withdrawal time compared to CC,but the difference was not statistically significant.The introduction of AIAC did not significantly change ADR(52.1%for AIAC vs 52.6%for CC,P=0.91)or SSLDR(17.4%for AIAC vs 18.1%for CC,P=0.44).CONCLUSION The implementation of AIAC failed to improve key markers of colonoscopy quality,including ADR,SSLDR and withdrawal time.Further research is required to assess the utility and cost-efficiency of AIAC for high performing endoscopists. 展开更多
关键词 Artificial intelligence Colonoscopy quality Adenoma detection rate Sessile serrated lesion detection rate Withdrawal time
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中国疫苗供应管理现状及挑战 被引量:1
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作者 李星辉 李梦颖 +5 位作者 付朝伟 严非 王娜 王伟 阿克忠 王颖 《中国卫生资源》 北大核心 2021年第2期150-152,共3页
目的分析全国31个省(自治区、直辖市)和新疆生产建设兵团(以下简称“兵团”)的疫苗供应管理现状,总结我国疫苗供应管理的经验及面临的挑战,为疫苗供应管理决策提供参考。方法对全国31个省(自治区、直辖市)的省(自治区、直辖市)级疾病预... 目的分析全国31个省(自治区、直辖市)和新疆生产建设兵团(以下简称“兵团”)的疫苗供应管理现状,总结我国疫苗供应管理的经验及面临的挑战,为疫苗供应管理决策提供参考。方法对全国31个省(自治区、直辖市)的省(自治区、直辖市)级疾病预防控制中心和兵团疾病预防控制中心进行机构问卷调查,调查内容为疫苗供应管理情况。结果全国31个省(自治区、直辖市)和兵团均出现过疫苗供应不及时的情况,供应延迟的平均天数普遍较长。疫苗配送的及时性总体良好。相比东中部地区,西部地区更需要采购应急疫苗。结论我国疫苗配送的及时性总体良好,对疫苗需求把控准确。但部分疫苗供应紧张,二类疫苗退出机制有待建立,西部地区在疫苗调动及库存把控方面有较大提升空间。 展开更多
关键词 疫苗vaccine 供应supply 管理management 配送distribution 二类疫苗typeⅡvaccine 退出机制withdrawal mechanism 应急疫苗emergent vaccine
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Recent Progress in Studies of the Variabilities and Mechanisms of the East Asian Monsoon in a Changing Climate 被引量:16
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作者 Wen CHEN Lin WANG +4 位作者 Juan FENG Zhiping WEN Tiaojiao MA Xiuqun YANG Chenghai WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第9期887-901,共15页
Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community... Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community and is particularly challenging in a changing climate where the global mean temperature has been rising.Recent advances in studies of the variabilities and mechanisms of the EAM are reviewed in this paper,focusing on the interannual to interdecadal time scales.Some new results have been achieved in understanding the behaviors of the EAM,such as the evolution of the East Asian summer monsoon(EASM),including both its onset and withdrawal over the South China Sea,the changes in the northern boundary activity of the EASM,or the transitional climate zone in East Asia,and the cycle of the EASM and the East Asian winter monsoon and their linkages.In addition,understanding of the mechanism of the EAM variability has improved in several aspects,including the impacts of different types of ENSO on the EAM,the impacts from the Indian Ocean and Atlantic Ocean,and the roles of mid-to high-latitude processes.Finally,some scientific issues regarding our understanding of the EAM are proposed for future investigation. 展开更多
关键词 EAST ASIAN summer MONSOON EAST ASIAN winter MONSOON CHANGING CLIMATE MONSOON onset and withdrawal transitional CLIMATE zone different types of ENSO
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ZD 7288,an HCN channel blocker,attenuates chronic visceral pain in irritable bowel syndrome-like rats 被引量:7
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作者 Yu Chen Chun Lin +3 位作者 Ying Tang Ai-Qin Chen Cui-Ying Liu Da-Li Lu 《World Journal of Gastroenterology》 SCIE CAS 2014年第8期2091-2097,共7页
AIM:To investigate the effects of ZD 7288,a hyperpolarization-activated cyclic nucleotide-gated(HCN)channel blocker,on rats with chronic visceral pain.METHODS:Rats with visceral hypersensitivity were generated using n... AIM:To investigate the effects of ZD 7288,a hyperpolarization-activated cyclic nucleotide-gated(HCN)channel blocker,on rats with chronic visceral pain.METHODS:Rats with visceral hypersensitivity were generated using neonatal colon irritation during postnatal days 8-15 as described previously.Visceral hypersensitivity was evaluated using electromyographic(EMG)responses of abdominal external oblique muscles to 20-80 mmHg colorectal distentions(CRD).Abdominal withdrawal reflex(AWR)scores and pain thresholds were also detected in adult rats.Different doses of ZD7288(25,50,and 100 nmol/L)were intrathecally administered in rats to study the role of spinal HCN channel in chronic visceral hypersensitivity.RESULTS:EMG responses to 20-80 mmHg CRD and AWR scores under 20-60 mmHg CRD significantly increased in rats with visceral hypersensitivity compared to control rats(P<0.05).The pain threshold in rats with visceral hypersensitivity significantly decreased compared to control rats(P<0.05).Treatment with50-100 nmol/L ZD 7288 significantly inhibited EMG responses(16%-62%,80-20 mmHg CRD,P<0.05)and AWR scores(24%-37%,40-20 mmHg CRD,P<0.05;12%-61%,80-20 mmHg CRD,P<0.05,respectively),and significantly increased pain thresholds(32%-77%,P<0.05).CONCLUSION:Spinal HCN channels may play an important role in chronic visceral hypersensitivity. 展开更多
关键词 ABDOMINAL WITHDRAWAL REFLEX ELECTROMYOGRAPHY HYPER
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Thermal behavior of the HTR-10 under combined PLOFC and ATWS condition initiated by unscrammed control rod withdrawal 被引量:5
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作者 Feng Gou Yuan Liu +1 位作者 Fu-Bing Chen Yu-Jie Dong 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第9期130-138,共9页
Two tests initiated by unscrammed control rod withdrawal were performed on the High Temperature GasCooled Reactor-Test Module(HTR-10) in November 2003 after the reactor achieved its full power, and the test conditions... Two tests initiated by unscrammed control rod withdrawal were performed on the High Temperature GasCooled Reactor-Test Module(HTR-10) in November 2003 after the reactor achieved its full power, and the test conditions represented a typical transient scenario of modular high-temperature reactors(HTRs), called pressurized loss of forced cooling, and anticipated transient without scram.Based on the test parameters, the HTR-10 thermal behaviors under the test conditions were studied with the help of the system analysis code THERMIX. The combination of the test results and the investigation results makes the HTR-10 safety potential better understood. Key phenomena, such as the helium natural circulation and the temperature redistribution in the reactor, were revealed. As the safety feature of most significance, there is a large margin between the maximum fuel temperature and its safety limit in each test. Temperatures of thermocouples in different components were calculated by THERMIX and compared with the test values. The applicability of the code was verified by good agreement obtained from the comparison. 展开更多
关键词 HTR-10 Control ROD WITHDRAWAL ATWS THERMIX
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Androgenic regulation of novel genes in the epididymis 被引量:5
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作者 Bernard Robaire Shayesta Seenundun +1 位作者 Mahsa Hamzeh Sophie-Anne Lamour 《Asian Journal of Andrology》 SCIE CAS CSCD 2007年第4期545-553,共9页
The epididymis is critically dependent on the presence of the testis. Although several hormones, such as retinoids and progestins, and factors secreted directly into the epididymal lumen, such as androgen binding prot... The epididymis is critically dependent on the presence of the testis. Although several hormones, such as retinoids and progestins, and factors secreted directly into the epididymal lumen, such as androgen binding protein and fibroblast growth factor, might play regulatory roles in epididymal function, testosterone (T) and its metabolites, dihydrotestosterone (DHT) and estradiol (E2), are accepted as the primary regulators of epididymal structure and functions, with the former playing the greater role. To ascertain the molecular action of androgens on the epididymis, three complementary approaches were pursued to monitor changes in gene expression in response to different hormonal milieux. The first was to establish changes in gene expression along the epididymis as androgenic support is withdrawn. The second was to determine the sequence of responses that occur in an androgen deprived tissue upon re-administration of the two metabolites of T, DHT and E2. The third was to study the effects of androgen withdrawal and re-administration on gene expression in immortalized murine caput epididymidal principal cells. Specific responses were observed under each of these conditions, with an expected major difference in the panoply of genes expressed upon hormone withdrawal and re-administration; however, some key common features were the common roles of genes in insulin like growth factor/epidermal growth factor and the relatively minor and specific effects of E2 as compared to DHT. Together, these results provide novel insights into the mechanisms of androgen regulation in epididymal principal cells. (Asian J Androl 2007 July; 9: 545-553) 展开更多
关键词 EPIDIDYMIS cell culture androgen withdrawal DIHYDROTESTOSTERONE ESTRADIOL apoptosis SURVIVIN insulin like growth factor
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Quality indicators for colonoscopy: Current insights and caveats 被引量:9
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作者 Hendrikus JM Pullens Peter D Siersema 《World Journal of Gastrointestinal Endoscopy》 CAS 2014年第12期571-583,共13页
Colonoscopy is the diagnostic modality of choice for investigation of symptoms suspected to be related to the colon and for the detection of polyps and colorectal cancer(CRC). Colonoscopy with removal of detected poly... Colonoscopy is the diagnostic modality of choice for investigation of symptoms suspected to be related to the colon and for the detection of polyps and colorectal cancer(CRC). Colonoscopy with removal of detected polyps has been shown to reduce the incidence and mortality of subsequent CRC. In many countries, population screening programs for CRC have been initiated, either by selection of patients for colonoscopy with fecal occult blood testing or by offering colonoscopy directly to average-risk individuals. Several endoscopy societies have formulated quality indicators for colonoscopy. These quality indicators are almost always incorporated as process indicators, rather than outcome measures. This review focuses on the quality indicators bowel preparation, cecal intubation rate, withdrawal time, adenoma detection rate, patient comfort, sedation and complication rate, and discusses the scientific evidence supporting them,as well as their potential shortcomings and issues that need to be addressed. For instance, there is still no clear and generally accepted definition of adequatebowel preparation, no robust scientific evidence is available supporting a cecal intubation rate ≥ 90% and the association between withdrawal time and occurrence of interval cancers has not been clarified. Adenoma detection rate is currently the only quality indicator that has been shown to be associated with interval colorectal cancer, but as an indicator it does not differentiate between subjects with one or more adenoma detected. 展开更多
关键词 COLONOSCOPY Quality indicators Bowel preparation Cecal INTUBATION WITHDRAWAL time ADENOMA detection rate Screening Complication Interval COLORECTAL CANCER Post-colonoscopy COLORECTAL CANCER
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The withdrawal of the U.S. from the Paris Agreement and its impact on global climate change governance 被引量:5
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作者 ZHANG Yong-Xiang CHAO Qing-Chen +1 位作者 ZHENG Qiu-Hong HUANG Lei 《Advances in Climate Change Research》 SCIE CSCD 2017年第4期213-219,共7页
The global community has prepared for the withdrawal of the U.S. from the Paris Agreement since Donald Trump was elected as the president of the U.S. However, Trump's formal declaration of withdrawal still caused ... The global community has prepared for the withdrawal of the U.S. from the Paris Agreement since Donald Trump was elected as the president of the U.S. However, Trump's formal declaration of withdrawal still caused worldwide reaction. Trump will use the withdrawal to build his political reputation and to renegotiate the Paris Agreement despite its negative effects on the political credibility, international relationships, and potential long-term economic growth of the U.S. In general, the withdrawal of the U.S. from the Paris Agreement will not change the development of low-carbon technologies and the transformation trend of the global climate governance regime. However, the long-term goals and international cooperation on climate change will be affected by budget cuts in American climate change research and the cancelation of donations from the multilateral environmental fund of the U.S. If the Paris Agreement is renegotiated, the common but differentiated principle of responsibility of the United Nations Framework Convention on Climate Change will be challenged again. Nevertheless, climate change governance remains a main theme of future sustainable development. Instead of national governments, local governments and non-governmental organizations will develop strategies for technical innovation and emphasize pragmatic cooperation, thus expanding their roles in climate change governance. The capacity building on climate change research and public awareness should be enhanced as a long-term objective of global climate change governance. 展开更多
关键词 U.S. withdraw PARIS AGREEMENT Global climate change GOVERNANCE IMPACT
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Effect of solidification parameters on the microstructures of a single crystal Ni-based superalloy AM3 被引量:4
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作者 Yu Zhuhuan Liu Lin +3 位作者 Zhao Xinbao Zhang Weiguo Zhang Jun Fu Hengzhi 《China Foundry》 SCIE CAS 2010年第3期217-223,共7页
A single crystal Ni-based superalloy AM3 was processed at withdraw rates of 3.5, 10, 50, 100, 200, and 500 μm·s-1, respectively.The as-cast microstructures and solidification segregation ratio were characterized... A single crystal Ni-based superalloy AM3 was processed at withdraw rates of 3.5, 10, 50, 100, 200, and 500 μm·s-1, respectively.The as-cast microstructures and solidification segregation ratio were characterized with various withdraw rates.The shape and size of carbide microstructures were determined.As expected, the primary and secondary dendrite arm spacings (PDAS and SDAS) decrease with the increase of withdraw rate.The highest volume fraction of eutectic γ/γ' is observed at the 100 μm·s-1 withdraw rate.The volume fraction of eutectic γ/γ' does not appear to be a strong function of the withdraw rate.With increasing withdraw rate, interface morphologies change in the sequence of planar, cellular, and dendrite.There is a general refinement of the microstructure as the withdraw rate increases.EPMA analysis showed that withdraw rate does not have obvious influence on the segregation of elements. 展开更多
关键词 Ni-based superalloy single crystal withdraw rate solidi fi cation PDAS SDAS
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