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Earthquake Emergency Response System of High-speed Railway by Least Square Method
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作者 Qizhou Hu Yikai Wu 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第2期1-11,共11页
This paper studies the Least Square Method to define high-speed railway(HSR) earthquake risk and solve the problem of its emergency response mechanism. Based on the construction of a monitoring system for HSR earthqua... This paper studies the Least Square Method to define high-speed railway(HSR) earthquake risk and solve the problem of its emergency response mechanism. Based on the construction of a monitoring system for HSR earthquake emergency response, the technical operational procedures for HSR seismic emergency response are proposed. The quantity, scale, and location of HSR earthquake emergency response mechanism are defined, and the corresponding emergency response system is built. In particular, the earthquake emergency response system can conduct real-time continuous dynamic monitoring of seismic activity along the railway. When earthquake occurs, the intensity of the ground motion is detected by the system. When the earthquake monitoring value reaches the earthquake alarm threshold, it will send an alarm signal to the dispatch center, and the emergency power supply will be forced to cut off. The earthquake emergency response system will continue to monitor the follow-up ground motion acceleration. The system provides the operation scheduling center with a basis for train operation control to resume operation after stopping. The monitoring result of the system reduces the disaster, and the secondary disaster is caused by the earthquake. This paper improves the HSR response mechanism in detecting earthquake disasters. The result improves the ability of HSR to deal with earthquake disasters, and reduces casualties and economic and property loss caused by earthquake disasters. 展开更多
关键词 high-speed railway(HSR) earthquake monitoring emergency response mechanism
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‘Outbreak Gold Standard’Selection to Provide Optimized Threshold for Infectious Diseases Early-alert Based on China Infectious Disease Automated-alert and Response System 被引量:5
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作者 王瑞平 姜永根 +2 位作者 赵根明 郭晓芹 Engelgau Michael 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第6期833-841,共9页
The China Infectious Disease Automated-alert and Response System(CIDARS) was successfully implemented and became operational nationwide in 2008. The CIDARS plays an important role in and has been integrated into the... The China Infectious Disease Automated-alert and Response System(CIDARS) was successfully implemented and became operational nationwide in 2008. The CIDARS plays an important role in and has been integrated into the routine outbreak monitoring efforts of the Center for Disease Control(CDC) at all levels in China. In the CIDARS, thresholds are determined using the ?Mean+2SD? in the early stage which have limitations. This study compared the performance of optimized thresholds defined using the ?Mean +2SD? method to the performance of 5 novel algorithms to select optimal ?Outbreak Gold Standard(OGS)? and corresponding thresholds for outbreak detection. Data for infectious disease were organized by calendar week and year. The ?Mean+2 SD?, C1, C2, moving average(MA), seasonal model(SM), and cumulative sum(CUSUM) algorithms were applied. Outbreak signals for the predicted value(Px) were calculated using a percentile-based moving window. When the outbreak signals generated by an algorithm were in line with a Px generated outbreak signal for each week, this Px was then defined as the optimized threshold for that algorithm. In this study, six infectious diseases were selected and classified into TYPE A(chickenpox and mumps), TYPE B(influenza and rubella) and TYPE C [hand foot and mouth disease(HFMD) and scarlet fever]. Optimized thresholds for chickenpox(P_(55)), mumps(P_(50)), influenza(P_(40), P_(55), and P_(75)), rubella(P_(45) and P_(75)), HFMD(P_(65) and P_(70)), and scarlet fever(P_(75) and P_(80)) were identified. The C1, C2, CUSUM, SM, and MA algorithms were appropriate for TYPE A. All 6 algorithms were appropriate for TYPE B. C1 and CUSUM algorithms were appropriate for TYPE C. It is critical to incorporate more flexible algorithms as OGS into the CIDRAS and to identify the proper OGS and corresponding recommended optimized threshold by different infectious disease types. 展开更多
关键词 outbreak gold standard optimized threshold algorithms early-alert signal China Infectious Disease Automated-alert and response system
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Oil spill model development and application for emergency response system 被引量:2
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《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2001年第2期252-256,共5页
关键词 Oil spill model development and application for emergency response system
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Introduction to China’s Earthquake Emergency Response System
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作者 Jianhong Liang Nan Xi +3 位作者 Jie Liu Jingqiong Yang Hongbo Shi Zhigao Yang 《Earthquake Science》 2021年第5期447-459,共13页
Following the M_(S)6.4 earthquake that occurred on May 21,2021 in Yangbi,Yunnan,China,the earthquake emergency response system(EERS)responded immediately.The real-time software delivered many seismic parameters that p... Following the M_(S)6.4 earthquake that occurred on May 21,2021 in Yangbi,Yunnan,China,the earthquake emergency response system(EERS)responded immediately.The real-time software delivered many seismic parameters that provided a preliminary assessment of the earthquake.The 24-hour on-duty staff and scientific researchers revised these parameters and produced more detailed reports to understand the cause of the earthquake and the potential damage,which provided valuable information for emergency rescue operations and earthquake situation assessment.Emergency personnel were dispatched immedia-tely to the earthquake site to observe the aftershocks,investigate the damage,and guide and assist in the relief efforts.This paper describes the EERS response to the Yangbi earthquake to demonstrate the characteristics of the system and discuss the potential for further improvement. 展开更多
关键词 emergency response system earthquake monitoring emergency product AUTOMATIC REVISION
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The Radio Technologies in City Emergency Response System
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作者 David Lum 《China Communications》 SCIE CSCD 2008年第4期99-103,共5页
Ⅰ. WHAT’S CERSThe City Emergency Response System (CERS) is a comprehensive system that provides the emergency relief and services for the citizen through an integrated communication and IT platform. With CERS, the
关键词 The Radio Technologies in City Emergency response system
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Analysis of Monitoring,Early Warning and Emergency Response System for New Major Infectious Diseases in China and Overseas 被引量:5
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作者 Xing-li DU Xin-rui ZHAO +2 位作者 Huan GAO Wan-wan SHEN Jia-zhi LIAO 《Current Medical Science》 SCIE CAS 2021年第1期62-68,共7页
In recent years,the impact of new major infectious diseases on people’s normal life is becoming more and more frequent,which has brought great impact on people’s life safety and social economy,especially the corona ... In recent years,the impact of new major infectious diseases on people’s normal life is becoming more and more frequent,which has brought great impact on people’s life safety and social economy,especially the corona virus disease 2019,which has been sweeping the globe.Public health and disease prevention and control systems in different countries have different performances in response to the pandemic,but they all have exposed many shortcomings.Countries around the world urgently need to improve the monitoring,early warning and emergency response systems for new major infectious diseases.As the outpost and main part of medical rescue,the hospital urgently needs to establish a set of scientifically advanced emergency response mechanism that is suitable for the business process of the medical system and unified standards in order to improve the response efficiency and quality of emergency treatment. 展开更多
关键词 infectious diseases MONITORING emergency response HOSPITAL
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Application of GIS to build earthquake emergency response system for urban area 被引量:1
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作者 汤爱平 谢礼立 陶夏新 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第1期38-42,共5页
A GIS based decision making system is designed for earthquake emergency response for city governments. The system could be used for seismic hazard assessment, earthquake damage and losses evaluation, emergency respons... A GIS based decision making system is designed for earthquake emergency response for city governments. The system could be used for seismic hazard assessment, earthquake damage and losses evaluation, emergency response and post earthquake recovering. The principle, design criteria, structure and functions of the system are described in detials. The system is composed of four parts: an information and data base, analytical modules, a decision making subsystem and a user interface. The information and data base consists of 68 coverages, including historically and instrumentally recorded earthquakes, seismo tectonic zones, active faults, potential source areas, isoseismals of scenario earthquake, soil profiles, characteristics of buildings, and all infrastructure systems such as: transportation network (roads and bridges, culverts), oil pipeline network, gas, water, electric power, communication etc., distribution of citizens, rush repair schemes of infrastructures and so on. There are also 28 analytical modules established in the system for generating isoseismals of scenario earthquake, site effects estimation, damage and losses evaluation and decision making for rescue, relief, evacuation and other emergency response actions. As an illustration, the operation of this system for reoccurrence of a historical earthquake is demonstrated. 展开更多
关键词 GEOGRAPHIC Information system EARTHQUAKE EMERGENCY response
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A framework for nuclear power plant emergency response system
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作者 Wang-kun CHEN 《Nuclear Science and Techniques》 SCIE CAS CSCD 2010年第6期375-378,共4页
The purpose of this study is to establish an intelligent expert system for nuclear power plant emergency response.A new framework of environmental risk management methodology by the concept of pattern recognition was ... The purpose of this study is to establish an intelligent expert system for nuclear power plant emergency response.A new framework of environmental risk management methodology by the concept of pattern recognition was introduced in this paper.A knowledge-based decision support system for emergency response and risk management of nuclear power plant was also discussed.The mathematical pattern relationship of accidental release effects on neighboring area and the corresponding response measures were presented in this paper.With this decision system,the decision maker can specify the procedure and minimize their human error in the decision process.The improvement of risk response and the quality of management system could be upgraded by this system.Besides,the methodology can also be served as a basis for the future development of environmental risk response system design. 展开更多
关键词 Expert system Emergency response Risk management Nuclear power plant
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Characteristics of In-Hospital Patients with Congenital Heart Disease Requiring Rapid Response System Activations: A Japanese Database Study
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作者 Taiki Haga Tomoyuki Masuyama +3 位作者 Yoshiro Hayashi Takahiro Atsumi Kenzo Ishii Shinsuke Fujiwara 《Congenital Heart Disease》 SCIE 2022年第1期31-43,共13页
Objectives:This study aimed to study the characteristics of in-hospital deterioration in patients with congenital heart disease who required rapid response system activation and identify risk factors associated with 1... Objectives:This study aimed to study the characteristics of in-hospital deterioration in patients with congenital heart disease who required rapid response system activation and identify risk factors associated with 1-month mortality.Methods:We retrospectively analysed data from a Japanese rapid response system registry with 35 participating hospitals.We included consecutive patients with congenital heart disease who required rapid response system activation between January 2014 and March 2018.Logistic regression analyses were performed to examine the associations between 1-month mortality and other patient-specific variables.Results:Among 9,607 patients for whom the rapid response system was activated,only 82(0.9%)had congenital heart disease.Only few patients with congenital heart disease were being treated at the cardiology and cardiovascular surgery departments(12.3%and 9.9%,respectively).Moreover,the incidences of rapid-response events after intensive care unit discharge or surgery were low(6.8% and 12.2%,respectively).The most common reason for rapid response system activation was respiratory dysfunction(desaturation:35.4%,tachypnoea:25.6%,and new dyspnoea:19.5%).Rapid response system interventions and intensive care unit transfers were required for 65.9% and 20.7%of patients,respectively.The mortality rate was 1.2% at the end of the rapid response system intervention and 11.0% after 1 month.Moreover,decreased respiratory rate and decreased heart rate at rapid response system activation were associated with increased 1-month mortality.The adjusted odds ratio was 1.10(95% confidence interval 1.02–1.19)and 1.02(95% confidence interval,1.00–1.04) for respiratory rate and heart rate,respectively.Conclusions:Rapid response systems were rarely activated after cardiac surgery and intensive care unit discharge,which were situations with a high risk of sudden deterioration in patients with congenital heart disease.Therefore,encouraging the use of the rapid response system in these departments will enable intervention by a third,specialised team for in-hospital emergencies and help provide comprehensive medical care to patients.Furthermore,1-month mortality was associated with vital signs at rapid response system activation.These findings may guide treatment selection for patients with congenital heart disease showing deterioration. 展开更多
关键词 Heart defects CONGENITAL EMERGENCIES clinical deterioration hospital rapid response team critical care This
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Distress Assessment and Response Systems in Patients With Cancer Pain
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作者 Hong Wei Li Guang Yang +4 位作者 Xiao Hui Ma Dong Sheng Xu Ling Ling Zhao Jiu Wei Cui Nan Ya Wang 《Journal of Nutritional Oncology》 2019年第3期132-137,共6页
Objective This study used the Distress Assessment and Response Tool(DART)to screen,evaluate,and explore physical symptoms,psychological problems,and social support in patients with cancer pain,with an aim to provide d... Objective This study used the Distress Assessment and Response Tool(DART)to screen,evaluate,and explore physical symptoms,psychological problems,and social support in patients with cancer pain,with an aim to provide data for the comprehensive care of these patients to improve their quality of life.Methods The DART was used to survey 497 patients with cancer pain who were admitted to the Cancer Center of the First Hospital of Jilin University from June 2014 to March 2017.All patients were diagnosed with malignant tumors by clinical,radiological and/or cytological examinations,and were experiencing tumor-related pain.This study recorded the patient’s somatic symptoms,psychological problems and social support in detail.After the data were collected,the SPSS 21.0 software was used to perform the statistical analysis,with the significance level set at P<0.05.Results In total,82.7%of patients were experiencing mild pain(NRS≤3);of these,29.7%and 15.8%reported depression and anxiety,respectively.In addition,17.3%of patients were experiencing moderate or severe pain(NRS≥4);of these,53.5%and 40.7%reported depression and anxiety,respectively.There was a statistically significant difference in the incidence of anxiety and depression between the two groups.Conclusion Patients with cancer pain,particularly those with moderate-to-severe pain,showed a high incidence of distress.In addition,they were likely to report physical symptoms,were conscious of poor health conditions,and were prone to have anxiety and depression.In terms of social support,patients with moderate-to-severe cancer pain should receive substantial support,as they experience work-related and economic concerns and report difficulties in family life and social activities. 展开更多
关键词 Cancer pain DISTRESS Pain assessment Distress Assessment and response Tool(DART) ANXIETY
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The physiological role of the unfolded protein response in the nervous system
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作者 Shuangchan Wu Wensheng Lin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2411-2420,共10页
The unfolded protein response(UPR)is a cellular stress response pathway activated when the endoplasmic reticulum,a crucial organelle for protein folding and modification,encounters an accumulation of unfolded or misfo... The unfolded protein response(UPR)is a cellular stress response pathway activated when the endoplasmic reticulum,a crucial organelle for protein folding and modification,encounters an accumulation of unfolded or misfolded proteins.The UPR aims to restore endoplasmic reticulum homeostasis by enhancing protein folding capacity,reducing protein biosynthesis,and promoting protein degradation.It also plays a pivotal role in coordinating signaling cascades to determine cell fate and function in response to endoplasmic reticulum stress.Recent research has highlighted the significance of the UPR not only in maintaining endoplasmic reticulum homeostasis but also in influencing various physiological processes in the nervous system.Here,we provide an overview of recent findings that underscore the UPR’s involvement in preserving the function and viability of neuronal and myelinating cells under physiological conditions,and highlight the critical role of the UPR in brain development,memory storage,retinal cone development,myelination,and maintenance of myelin thickness. 展开更多
关键词 MYELIN NEURON OLIGODENDROCYTE Schwann cell unfolded protein response
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Dynamic thermo-mechanical responses of road-soft ground system under vehicle load and daily temperature variation
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作者 Chuxuan Tang Jie Liu +3 位作者 Zheng Lu Yang Zhao Jing Zhang Yinuo Feng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1722-1731,共10页
A complete road-soft ground model is established in this paper to study the dynamic responses caused by vehicle loads and/or daily temperature variation.A dynamic thermo-elastic model is applied to capturing the behav... A complete road-soft ground model is established in this paper to study the dynamic responses caused by vehicle loads and/or daily temperature variation.A dynamic thermo-elastic model is applied to capturing the behavior of the rigid pavement,the base course,and the subgrade,while the soft ground is characterized using a dynamic thermo-poroelastic model.Solutions to the road-soft ground system are derived in the Laplace-Hankel transform domain.The time domain solutions are obtained using an integration approach.The temperature,thermal stress,pore water pressure,and displacement responses caused by the vehicle load and the daily temperature variation are presented.Results show that obvious temperature change mainly exists within 0.3 m of the road when subjected to the daily temperature variation,whereas the stress responses can still be found in deeper places because of the thermal swelling/shrinkage deformation within the upper road structures.Moreover,it is important to consider the coupling effects of the vehicle load and the daily temperature variation when calculating the dynamic responses inside the road-soft ground system. 展开更多
关键词 Dynamic response Vehicle load Daily temperature variation Thermo-poroelastic medium Coupling effects
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NIR-triggered on-site NO/ROS/RNS nanoreactor:Cascade-amplified photodynamic/photothermal therapy with local and systemic immune responses activation
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作者 Ziqing Xu Yakun Kang +9 位作者 Jie Zhang Jiajia Tang Hanyao Sun Yang Li Doudou He Xuan Sha Yuxia Tang Ziyi Fu Feiyun Wu Shouju Wang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第6期58-73,共16页
Photothermal and photodynamic therapies(PTT/PDT)hold promise for localized tumor treatment,yet their full potential is hampered by limitations such as the hypoxic tumor microenvironment and inadequate systemic immune ... Photothermal and photodynamic therapies(PTT/PDT)hold promise for localized tumor treatment,yet their full potential is hampered by limitations such as the hypoxic tumor microenvironment and inadequate systemic immune activation.Addressing these challenges,we present a novel near-infrared(NIR)-triggered RNS nanoreactor(PBNO-Ce6)to amplify the photodynamic and photothermal therapy efficacy against triple-negative breast cancer(TNBC).The designed PBNOCe6 combines sodium nitroprusside-doped Prussian Blue nanoparticles with Chlorin e6 to enable on-site RNS production through NIR-induced concurrent NO release and ROS generation.This not only enhances tumor cell eradication but also potentiates local and systemic antitumor immune responses,protecting mice from tumor rechallenge.Our in vivo evaluations revealed that treatment with PBNO-Ce6 leads to a remarkable 2.7-fold increase in cytotoxic T lymphocytes and a 62%decrease in regulatory T cells in comparison to the control PB-Ce6(Prussian Blue nanoparticles loaded with Chlorin e6),marking a substantial improvement over traditional PTT/PDT.As such,the PBNO-Ce6 nanoreactor represents a transformative approach for improving outcomes in TNBC and potentially other malignancies affected by similar barriers. 展开更多
关键词 photothermal therapy photodynamic therapy nitric oxide reactive nitrogen species triple-negative breast cancer immune response NANOREACTOR
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Systemic Inflammation Response Index and weight loss as prognostic factors in metastatic pancreatic cancer: A concept study from the PANTHEIA-SEOM trial
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作者 Vilma Pacheco-Barcia Sara Custodio-Cabello +7 位作者 Fatima Carrasco-Valero Magda Palka-Kotlowska Axel Mariño-Mendez Alberto Carmona-Bayonas Javier Gallego A J Muñoz Martín Paula Jimenez-Fonseca Luis Cabezon-Gutierrez 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第2期386-397,共12页
BACKGROUND The prognostic value of the Systemic Inflammation Response Index(SIRI)in advanced pancreatic cancer is recognized,but its correlation with patients´nutritional status and outcomes remains unexplored.AI... BACKGROUND The prognostic value of the Systemic Inflammation Response Index(SIRI)in advanced pancreatic cancer is recognized,but its correlation with patients´nutritional status and outcomes remains unexplored.AIM To study the prognostic significance of SIRI and weight loss in metastatic pancreatic cancer.METHODS The PANTHEIA-Spanish Society of Medical Oncology(SEOM)study is a multicentric(16 Spanish hospitals),observational,longitudinal,non-interventional initiative,promoted by the SEOM Real World-Evidence work group.This pilot study sought to analyze the association between weight loss and inflammatory status as defined by SIRI.The cohort stems from a proof-of-concept pilot study conducted at one of the coordinating centers.Patients with pathologically confirmed metastatic pancreatic adenocarcinoma,treated from January 2020 to January 2023,were included.The index was calculated using the product of neutrophil and monocyte counts,divided by lymphocyte counts,obtained within 15 days before initiation chemotherapy.This study evaluated associations between overall survival(OS),SIRI and weight loss.RESULTS A total of 50 patients were included.66%of these patients were male and the median age was 66 years.Metastasis sites:36%liver,12%peritoneal carcinomatosis,10%lung,and 42%multiple locations.Regarding the first line palliative chemotherapy treatments:50%received gemcitabine plus nab-paclitaxel;28%,modified fluorouracil,leucovorin,irinotecan and oxaliplatin,and 16%were administered gemcitabine.42%had a weight loss>5%in the three months(mo)preceding diagnosis.21 patients with a SIRI≥2.3×10^(3)/L exhibited a trend towards a lower median OS compared to those with a SIRI<2.3×10^(3)/L(4 vs 18 mo;P<0.000).Among 21 patients with>5%weight loss before diagnosis,the median OS was 6 mo,in contrast to 19 mo for those who did not experience such weight loss(P=0.003).Patients with a weight loss>5%showed higher SIRI levels.This difference was statistically significant(P<0.000).For patients with a SIRI<2.3×10^(3)/L,those who did not lose>5%of their weight had an OS of 20 mo,compared to 11 mo for those who did(P<0.001).No association was found between carbohydrate antigen 19-9 levels≥1000 U/mL and weight loss.CONCLUSION A higher SIRI was correlated with decreased survival rates in patients with metastatic pancreatic cancer and associated with weight loss.An elevated SIRI is suggested as a predictor of survival,emphasizing the need for prospective validation in the upcoming PANTHEIA-SEOM study. 展开更多
关键词 Pancreatic cancer NUTRITION Prognostic factor INFLAMMATION Advanced cancer systemic inflammatory response index Weight loss
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Systemic inflammatory response index is a predictor of prognosis in gastric cancer patients: Retrospective cohort and meta-analysis
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作者 Jing-Yao Ren Meng Xu +5 位作者 Xiang-Dong Niu Shi-Xun Ma Ya-Jun Jiao Da Wang Miao Yu Hui Cai 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期382-395,共14页
BACKGROUND The systemic inflammatory response index(SIRI)has been demonstrated to make a significant difference in assessing the prognosis of patients with different solid neoplasms.However,research is needed to ascer... BACKGROUND The systemic inflammatory response index(SIRI)has been demonstrated to make a significant difference in assessing the prognosis of patients with different solid neoplasms.However,research is needed to ascertain the accuracy and reliability of applying the SIRI to patients who undergo robotic radical gastric cancer sur-gery.AIM To validate the applicability of the SIRI in assessing the survival of gastric cancer patients and evaluate the clinical contribution of preoperative SIRI levels to predicting long-term tumor outcomes in patients,who received robotic radical gastric cancer surgery.METHODS Initially,an exhaustive retrieval was performed in the PubMed,the Cochrane Library,EMBASE,Web of Science,and Scopus databases to identify relevant studies.Subsequently,a meta-analysis was executed on 6 cohort studies iden-tifying the value of the SIRI in assessing the survival of gastric cancer patients.Additionally,the clinical data of 161 patients undergoing robotic radical gastric cancer surgery were retrospectively analyzed to evaluate their clinicopathological characteristics and relevant laboratory indicators.The association between preoperative SIRI levels and 5-year overall survival(OS)and disease-free survival(DFS)was assessed.RESULTS The findings demonstrated an extensive connection between SIRI values and the outcome of patients with gastric cancer.Preoperative SIRI levels were identified as an independent hazard feature for both OS and DFS among those who received robotic surgery for gastric cancer.SIRI levels in gastric cancer patients were observed to be associated with the presence of comorbidities,T-stage,carcinoembryonic antigen levels,the development of early serious postoperative complications,and the rate of lymph node metastasis.CONCLUSION SIRI values are correlated with adverse in the gastric cancer population and have the potential to be utilized in predicting long-term oncological survival in patients who undergo robotic radical gastric cancer surgery. 展开更多
关键词 systemic inflammatory response index PROGNOSIS Gastric cancer COMPLICATIONS META-ANALYSIS
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Influence of span-to-depth ratio on dynamic response of vehicle-turnoutbridge system in high-speed railway
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作者 Chuanqing Dai Tao Xin +3 位作者 Shenlu Qiao Yanan Zhang Pengsong Wang Mahantesh M.Nadakatti 《High-Speed Railway》 2024年第1期30-41,共12页
For high-speed railways,the smoothness of the railway line significantly affects the operational speed of trains.When the train passes through the turnout on a long-span bridge,the wheel-rail impacts caused by the tur... For high-speed railways,the smoothness of the railway line significantly affects the operational speed of trains.When the train passes through the turnout on a long-span bridge,the wheel-rail impacts caused by the turnout structure irregularities,and the instability arising from the bridge's flexural deformation lead to a strong coupling effect in the vehicle-turnout-bridge system.This significantly affects both ride comfort and operational safety.For addressing this issue,the present study considered a long-span continuous rigid-frame bridge as an example and established a train-turnout-bridge coupled dynamic model of high-speed railway.Utilizing a selfdeveloped dynamic simulation program,the study analysed the dynamic response characteristics when the train passes through the turnouts on the bridge.It also investigated the influence of different span-to-depth ratios of the bridge on the vehicle dynamic response when the train passes through the main line and branch line of turnouts and then proposed a span-to-depth ratio limit value for a long-span continuous rigid-frame bridge.The research findings suggest that the changes in the span-to-depth ratio have a relatively minor impact on the train’s operational performance but significantly affect the dynamic characteristics of the bridge structure.Based on the findings and a comprehensive assessment of safety indicators,it is advisable to establish a span-to-depth ratio limit of 1/4500 for a long-span continuous rigid-frame bridge. 展开更多
关键词 Turnout on bridge Span-to-depth ratio Dynamic response Vehicle-turnout-bridge system High-speed railway
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A cross-sectional study on the nurses’attitude towards rapid response system activation for clinically deteriorated patients
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作者 Salamah Ahmed Taher Alnajei Jefferson Garcia Guerrero 《Nursing Communications》 2024年第6期1-8,共8页
Background:Hospitals have reported that implementing rapid response system activation(RRS)activation has increased patient safety.As a result,there has been growing interest in identifying factors that lead to success... Background:Hospitals have reported that implementing rapid response system activation(RRS)activation has increased patient safety.As a result,there has been growing interest in identifying factors that lead to successful RRS activation.While introducing an automated RRS activation system has prompted nurses to be more vigilant about monitoring vital signs,it has not necessarily encouraged them to conduct thorough patient assessments to identify early signs of deterioration.Purpose:The current study aimed to assess nurses’attitudes towards RRS activation for clinically deteriorated patients in the clinical units of King Abdul-Aziz Hospital.Methods:A descriptive cross-sectional research design was utilised in the study,and 144 nurses working in the medical and surgical units of King Abdul-Aziz Hospital were recruited to participate using a convenient non-probability sampling technique.Results:The study’s findings reported that nurses have a positive attitude towards RRS benefits(Mean=3.70;SD=0.70).Their overall attitude towards RRS activation among clinically deteriorated patients is still low positive(Mean=2.71;SD=0.61).The nurses’attitudes towards RRS benefits significantly differ among nationalities and the clinical area/unit where they were assigned,with a P-value of 0.0194 and 0.000,respectively.Attitudes towards RRS barriers significantly differ among nationality(P-value=0.0037),education level(P-value=0.0032),area of assignment(P-value=0.020),and whether they have a good understanding of abnormal observations(P-value=0.0122).Regarding the nurses’attitude towards management belief,the significant result is only with the clinical area/unit of assignment with a P-value of 0.000.Conclusion:The current study found a low positive attitude towards RRS activation among ward nurses,especially given that monitoring vital signs is critical to their job.Nurses may fear being perceived as clinically inept for redundant activations caused by poor quality,but their attitude towards activating the RRS in clinical deterioration is still largely negative.This is because most RRSs rely on ward nurses to recognise clinical deterioration and manually alert responders through phone calls,hospital communication systems,or face-to-face communication. 展开更多
关键词 rapid response team rapid response system clinically deteriorated patients cardiopulmonary arrest medical-surgical nurses
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Semi-analytical steady-state response prediction for multi-dimensional quasi-Hamiltonian systems
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作者 叶文伟 陈林聪 +2 位作者 原子 钱佳敏 孙建桥 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期177-186,共10页
The majority of nonlinear stochastic systems can be expressed as the quasi-Hamiltonian systems in science and engineering. Moreover, the corresponding Hamiltonian system offers two concepts of integrability and resona... The majority of nonlinear stochastic systems can be expressed as the quasi-Hamiltonian systems in science and engineering. Moreover, the corresponding Hamiltonian system offers two concepts of integrability and resonance that can fully describe the global relationship among the degrees-of-freedom(DOFs) of the system. In this work, an effective and promising approximate semi-analytical method is proposed for the steady-state response of multi-dimensional quasi-Hamiltonian systems. To be specific, the trial solution of the reduced Fokker–Plank–Kolmogorov(FPK) equation is obtained by using radial basis function(RBF) neural networks. Then, the residual generated by substituting the trial solution into the reduced FPK equation is considered, and a loss function is constructed by combining random sampling technique. The unknown weight coefficients are optimized by minimizing the loss function through the Lagrange multiplier method. Moreover, an efficient sampling strategy is employed to promote the implementation of algorithms. Finally, two numerical examples are studied in detail, and all the semi-analytical solutions are compared with Monte Carlo simulations(MCS) results. The results indicate that the complex nonlinear dynamic features of the system response can be captured through the proposed scheme accurately. 展开更多
关键词 steady-state response quasi-Hamiltonian systems FPK equation RBF neural networks
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Biomechanical Response of the Root System in Tomato Seedlings under Wind Disturbance
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作者 Zhengguang Liu Jun Yang +2 位作者 Tobi Fadiji Zhiguo Li Jiheng Ni 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第4期1071-1090,共20页
Wind disturbance as a green method can effectively prevent the overgrowth of tomato seedlings,and its mechanism may be related to root system mechanics.This study characterized the biophysical mechanical properties of... Wind disturbance as a green method can effectively prevent the overgrowth of tomato seedlings,and its mechanism may be related to root system mechanics.This study characterized the biophysical mechanical properties of taproot and lateral roots of tomato seedlings at five seedling ages and seedling substrates with three different moisture content.The corresponding root system-substrate finite element(FE)model was then developed and validated.The study showed that seedling age significantly affected the biomechanical properties of the taproot and lateral roots of the seedlings and that moisture content significantly affected the biomechanical properties of the seedling substrate(p<0.05).The established FE model was sensitive to wind speed,substrate moisture content,strong seedling index,and seedling age and was robust.The multiple linear regression equations obtained could predict the maximum stress and strain of the root system of tomato seedlings in the wind field.The strong seedling index had the greatest impact on the biomechanical response of the seedling root system during wind disturbance,followed by wind speed.In contrast,seedling age had no significant effect on the biomechanical response of the root system during wind disturbance.In the simulation,no mechanical damage was observed on the tissue of the seedling root system,but there were some strain behaviors.Based on the plant stress resistance,wind disturbance may affect the growth and development of the root system in the later growth stage.In this study,finite element and statistical analysis methods were combined to provide an effective approach for indepth analysis of the biomechanical mechanisms of wind disturbances that inhibit tomato seedlings’growth from the root system’s perspective. 展开更多
关键词 Tomato seedling root system age level wind disturbance biomechanical response finite element analysis
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Response Spectrum Analysis of 7-story Assembled Frame Structure with Energy Dissipation System
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作者 Jin Zhao Yi Wang Zhengwei Ma 《Structural Durability & Health Monitoring》 EI 2023年第2期159-173,共15页
Viscoelastic damper is an effective passive damping device,which can reduce the seismic response of the structure by increasing the damping and dissipating the vibration energy of structures.It has a wide application ... Viscoelastic damper is an effective passive damping device,which can reduce the seismic response of the structure by increasing the damping and dissipating the vibration energy of structures.It has a wide application prospect in actual structural vibration control because of simple device and economical material.In view of the poor seismic behaviors of assembled frame structure connections,various energy dissipation devices are proposed to improve the seismic performance.The finite element numerical analysis method is adopted to analyze relevant energy dissipation structural parameters.The response spectrum of a 7-story assembled frame structure combined the ordinary steel support,ordinary viscoelastic damper,and viscoelastic damper with displacement amplification device is analyzed.The analysis results show that the mechanical behavior of assembled frame structure with ordinary steel supports are not significantly different from those without energy dissipation devices.The assembled frame structure with viscoelastic damper has better seismic performance and energy dissipation,especially for the viscoelastic damper with displacement amplification devices.The maximum value of inter-story displacement angle decreases by 32.24%;the maximum floor displacement decreases by 31.91%,and the base shear decreases by 13.62%compared with the assembled frame structures without energy dissipation devices.The results show that the seismic fortification ability of the structure is significantly improved,and the overall structure is more uniformly stressed.The damping structure with viscoelastic damper mainly reduces the dynamic response of the structure by increasing the damping coefficient,rather than by changing the natural vibration period of the structure.This paper provides an effective theoretical basis and reference for improving the energy dissipation system and the seismic performance of assembled frame structures. 展开更多
关键词 Assembled frame structure energy dissipation devices response spectrum analysis viscoelastic damper
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