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Linking 24-h Movement Behavior Guidelines to Cognitive Difficulties,Internalizing and Externalizing Problems in Preterm Youth 被引量:1
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作者 Zhihui Cheng Ailikute Aikeremu +6 位作者 Yanping Gao Zhihao Zhang Anthony G.Delli Paoli Paolo Marcello Cunha Alyx Taylor Fabian Herold Liye Zou 《International Journal of Mental Health Promotion》 2024年第8期651-662,共12页
Background:Given the heightened risk of developmental challenges associated with preterm birth,it is crucial to explore interventions that may ameliorate potential adverse outcomes.This study aimed to examine whether ... Background:Given the heightened risk of developmental challenges associated with preterm birth,it is crucial to explore interventions that may ameliorate potential adverse outcomes.This study aimed to examine whether meeting the 24-h movement behavior(24-HMB)guidelines,which include recommendations on physical activity(PA),screen time(ST),and sleep(SL),is related to indicators of cognitive difficulties,internalizing problems(e.g.,depression and anxiety),and externalizing problems(e.g.,difficulties in making friends and arguing)in a sample of preterm youth(children and adolescents born preterm).Methods:In this cross-sectional study,data from 3410 preterm youth(aged 6 to 17 years)were included for data analyses.Multivariable logistic regression was used to investigate associations between meeting the 24-HMB guidelines and the above-mentioned health outcomes,while controlling for sociodemographic and health-related factors.Results:The prevalence of meeting 24-HMB guidelines varied across independent and integrated components of the 24-HMB guidelines.Meeting the ST guideline alone(p<0.05)and integrated guidelines(i.e.,ST+SL and ST+SL+PA)were associated with fewer cognitive difficulties and reduced internalizing and externalizing problems(p<0.05).Specifically,meeting the SL guideline alone and integrated guidelines(i.e.,SL+ST)were associated with lower odds of depression and anxiety(p<0.01).Additionally,meeting independent,and integrated(PA and/or ST)guidelines were associated with less pronounced difficulties in making friends and arguing(p<0.05).Meeting 24-HMB guidelines in an isolated and integrated manner are linked to better cognitive performance and fewer internalizing and externalizing problems in preterm youth.Conclusion:Results suggest that advocating for the implementation of the 24-HMB guidelines may reduce cognitive challenges and behavioral issues,which is of high relevance for improving public health.Future longitudinal studies in preterm youth should investigate how modifying specific 24-HMB behaviors,especially ST,influence cognitive difficulties,internalizing and externalizing problems in this vulnerable population. 展开更多
关键词 Cognitive difficulties externalizing problems internalizing problems physical activity preterm youth
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Operational definitions and measurement of externalizing behavior problems:An integrative review including research models and clinical diagnostic systems
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作者 Lidia Torres-Rosado Oscar M Lozano +2 位作者 Manuel Sanchez-Garcia Fermín Fernández-Calderón Carmen Diaz-Batanero 《World Journal of Psychiatry》 SCIE 2023年第6期278-297,共20页
Measurement of externalizing disorders such as antisocial disorders,attentiondeficit/hyperactivity disorder or borderline disorder have relevant implications for the daily lives of people with these disorders.While th... Measurement of externalizing disorders such as antisocial disorders,attentiondeficit/hyperactivity disorder or borderline disorder have relevant implications for the daily lives of people with these disorders.While the Diagnostic and Statistical Manual of Mental Disorders(DSM)and the International Classification of Diseases(ICD)have provided the diagnostic framework for decades,recent dimensional frameworks question the categorical approach of psychopathology,inherent in traditional nosotaxies.Tests and instruments develop under the DSM or ICD framework preferentially adopt this categorical approach,providing diagnostic labels.In contrast,dimensional measurement instruments provide an individualized profile for the domains that comprise the externalizing spectrum,but are less widely used in practice.Current paper aims to review the operational definitions of externalizing disorders defined under these different frameworks,revise the different measurement alternatives existing,and provide an integrative operational definition.First,an analysis of the operational definition of externalizing disorders among the DSM/ICD diagnostic systems and the recent Hierarchical Taxonomy of Psychopathology(HiTOP)model is carried out.Then,in order to analyze the coverage of operational definitions found,a description of measurement instruments among each conceptualization is provided.Three phases in the development of the ICD and DSM diagnosis systems can be observed with direct implications for measurement.ICD and DSM versions have progressively introduced systematicity,providing more detailed descriptions of diagnostic criteria and categories that ease the measurement instrument development.However,it is questioned whether the DSM/ICD systems adequately modelize externalizing disorders,and therefore their measurement.More recent theoretical approaches,such as the HiTOP model seek to overcome some of the criticism raised towards the classification systems.Nevertheless,several issues concerning this model raise mesasurement challenges.A revision of the instruments underneath each approach shows incomplete coverage of externalizing disorders among the existing instruments.Efforts to bring nosotaxies together with other theoretical models of psychopathology and personality are still needed.The integrative operational definition of externalizing disorders provided may help to gather clinical practice and research. 展开更多
关键词 externalizing disorders Measurement Diagnostic and Statistical Manual of Mental Disorders International Classification of Diseases Hierarchical Taxonomy of Psychopathology PSYCHOPATHOLOGY
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Evidence for the Reliability and Validity of the Arabic Version of the Student Risk Screening Scale for Internalizing and Externalizing Behaviors (SRSS-IE)
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作者 Sumayah A. Alrubayie Keetam D. F. Alkahtani 《Journal of Behavioral and Brain Science》 2024年第1期32-45,共14页
School-based universal screening for behavioral/emotional risk is a necessary first step to providing services in an educational setting for students with emotional and behavioral disorders (EBDs). Psychometric proper... School-based universal screening for behavioral/emotional risk is a necessary first step to providing services in an educational setting for students with emotional and behavioral disorders (EBDs). Psychometric properties are critical to making decisions about choosing a screening instrument. The purpose of the present study was to examine the psychometric properties of the student risk screening scale for internalizing and externalizing behaviors (SRSS-IE). Participants included 3145 students and their teachers. Item-level analyses of the current sample supported the retention of all items. The internal consistency of the SRSS items ranged from 0.83 to 0.85. Convergent validity between the SRSS-IE and a well-established screening tool, the strength and difficulties questionnaire (SDQ), was found for the total score (r = 0.70). Additionally, the results of this study demonstrate strong social validity, suggesting the SRSS-IE to be a useful and functional screening tool. We conclude that the SRSS-IE is a valid and reliable instrument for assessing the level of emotional and behavioral difficulties among elementary students. 展开更多
关键词 The Student Risk Screening Scale for Internalizing and externalizing Behaviors (SRSS-IE) Strength and Difficulties Questionnaire (SDQ) Emotional and Behavioral Difficulties Screening Tools Systematic Screening
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Differential Impact of an Executive-Function and a Social Cognition Training on Preschoolers with Externalizing Behavior Problems
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作者 Marine Houssa Alexandra Volckaert +1 位作者 Nathalie Nader-Grosbois Marie-Pascale Noel 《Journal of Behavioral and Brain Science》 2017年第12期598-620,共23页
In preschoolers, externalizing behavior problems are a primary cause of consultation. It is known that externalizing behavior (EB) could result from individual and environmental risk factors. Individual risk factors i... In preschoolers, externalizing behavior problems are a primary cause of consultation. It is known that externalizing behavior (EB) could result from individual and environmental risk factors. Individual risk factors included notably social cognition (SC) and executive functions (EF). A high level of EB has usually been related to dysfunction in SC and to poor skills in EF. The aim of the present experimental study is to compare the impact of two very targeted child-oriented trainings in the increasing of social competence and decreasing of EB in preschoolers. One training targeted SC abilities while the second one targeted EF capacities. These two trainings were compared on 48 preschoolers presenting clinically relevant levels of EB. The comparison of those results highlighted how each training could help preschoolers with EB in their behavior, emotion regulation and social adjustment. In comparison to a waiting-list control-group, the two trainings were effective in decreasing EB and differentiated impacts of the two trainings were obtained on different dimensions of profiles of social competence and emotion regulation. Results are discussed for their research and clinical implications. 展开更多
关键词 externalizing Behavior PRESCHOOLERS Social Cognition Executive Functions TRAINING Emotion Regulation
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Prenatal risk factors for internalizing and externalizing problems in childhood 被引量:1
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作者 Joyce Tien Gary D.Lewis Jianghong Liu 《World Journal of Pediatrics》 SCIE CAS CSCD 2020年第4期341-355,共15页
Background A growing body of research has documented the effects of prenatal risk factors on a wide spectrum of adverse offspring health outcomes.Childhood behavior problems,such as externalizing and internalizing pro... Background A growing body of research has documented the effects of prenatal risk factors on a wide spectrum of adverse offspring health outcomes.Childhood behavior problems,such as externalizing and internalizing problems,are no exception.This comprehensive literature review aims to summarize and synthesize current research about commonly experienced prenatal risk factors associated with internalizing and externalizing problems,with a focus on their impact during childhood and adolescence.Potential mechanisms as well as implications are also outlined.Data sources The EBSCO,Web of Science,PubMed,Google Scholar,and Scopus databases were searched for studies examining the association between prenatal risk factors and offspring internalizing/externalizing problems,using keywords“prenatal”or“perinatal”or“birth complications”in combination with“internalizing”or“externalizing”.Relevant articles,including experimental research,systematic reviews,meta-analyses,cross-sectional and longitudinal cohort studies,and theoretical literature,were reviewed and synthesized to form the basis of this integrative review.Results Prenatal risk factors that have been widely investigated with regards to offspring internalizing and externalizing problems encompass health-related risk factors,including maternal overweight/obesity,substance use/abuse,environmental toxicant exposure,maternal infection/inflammation,as well as psychosocial risk factors,including intimate partner violence,and anxiety/depression.Collectively,both epidemiological and experimental studies support the adverse associations between these prenatal factors and increased risk of emotional/behavioral problem development during childhood and beyond.Potential mechanisms of action underlying these associations include hormonal and immune system alterations.Implications include prenatal education,screening,and intervention strategies.Conclusions Prenatal risk factors are associated with a constellation of offspring internalizing and externalizing problems.Identifying these risk factors and understanding potential mechanisms will help to develop effective,evidence-based prevention,and intervention strategies. 展开更多
关键词 externalizing INTERNALIZING OBSTETRICAL Pregnancy Prenatal risk factors
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GPU‑accelerated Monte Carlo method for dose calculation of mesh‑type computational phantoms
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作者 Shu‑Chang Yan Rui Qiu +3 位作者 Xi‑Yu Luo An‑Kang Hu Zhen Wu Jun‑Li Li 《Nuclear Science and Techniques》 2026年第1期297-308,共12页
Computational phantoms play an essential role in radiation dosimetry and health physics.Although mesh-type phantoms offer a high resolution and adjustability,their use in dose calculations is limited by their slow com... Computational phantoms play an essential role in radiation dosimetry and health physics.Although mesh-type phantoms offer a high resolution and adjustability,their use in dose calculations is limited by their slow computational speed.Progress in heterogeneous computing has allowed for substantial acceleration in the computation of mesh-type phantoms by utilizing hardware accelerators.In this study,a GPU-accelerated Monte Carlo method was developed to expedite the dose calculation for mesh-type computational phantoms.This involved designing and implementing the entire procedural flow of a GPUaccelerated Monte Carlo program.We employed acceleration structures to process the mesh-type phantom,optimized the traversal methodology,and achieved a flattened structure to overcome the limitations of GPU stack depths.Particle transport methods were realized within the mesh-type phantom,encompassing particle location and intersection techniques.In response to typical external irradiation scenarios,we utilized Geant4 along with the GPU program and its CPU serial code for dose calculations,assessing both computational accuracy and efficiency.In comparison with the benchmark simulated using Geant4 on the CPU using one thread,the relative differences in the organ dose calculated by the GPU program predominantly lay within a margin of 5%,whereas the computational time was reduced by a factor ranging from 120 to 2700.To the best of our knowledge,this study achieved a GPU-accelerated dose calculation method for mesh-type phantoms for the first time,reducing the computational time from hours to seconds per simulation of ten million particles and offering a swift and precise Monte Carlo method for dose calculation in mesh-type computational phantoms. 展开更多
关键词 GPU Monte Carloference Mesh-type phantom External exposure Heterogeneous
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Controlling externally solidified crystals and porosity for enhancing mechanical properties of a die-casting aluminum-silicon alloy
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作者 Yi-hui Zhang Xiang-yi Jiao +6 位作者 Peng-yue Wang Yi-xian Liu Jin-rui Wang Wen-ning Liu Li-jun Shi Cheng-gang Wang Shou-mei Xiong 《China Foundry》 2026年第1期94-100,共7页
The effects of the high pressure die casting(HPDC)processes on porosity,microstructure,and mechanical properties of heat-treatment-free aluminum silicon(Al-Si)alloys have long been a focal point in automotive die-cast... The effects of the high pressure die casting(HPDC)processes on porosity,microstructure,and mechanical properties of heat-treatment-free aluminum silicon(Al-Si)alloys have long been a focal point in automotive die-casting research.In this work,the combined effect of shot sleeve materials and slow shot speeds on porosity,microstructure and mechanical properties of a newly designed HPDC Al-Si alloy was investigated.Results show that employing a ceramic shot sleeve or increasing the slow shot speed significantly reduces both the average size and area fraction of externally solidified crystals(ESCs),as well as the average pore size and volume fraction.When the slow shot speed is increased from 0.05 m·s^(-1)to 0.1 m·s^(-1),the pore volume fraction decreases by 10.2%in steel-shot-sleeve samples,compared to a substantial 67.1%reduction in ceramic-shot-sleeve samples.At a slow shot speed of 0.1 m·s^(-1),castings produced with a ceramic shot sleeve exhibit superior mechanical properties:8.3%higher yield strength,17.4%greater tensile strength,and an 81.4%improvement in elongation,relative to those from a steel shot sleeve.These findings provide valuable insights for minimizing porosity and coarse ESCs in die castings,offering promising potential for broader industrial applications. 展开更多
关键词 high pressure die casting aluminum-silicon alloy externally solidified crystals POROSITY shot sleeve
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Extreme Attitude Prediction of Amphibious Vehicles Based on Improved Transformer Model and Extreme Loss Function
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作者 Qinghuai Zhang Boru Jia +3 位作者 Zhengdao Zhu Jianhua Xiang Yue Liu Mengwei Li 《哈尔滨工程大学学报(英文版)》 2026年第1期228-238,共11页
Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instabili... Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instability,occur frequently in both experimental and operational data.This infrequency causes events to be overlooked by existing prediction models,which lack the precision to accurately predict inclination attitudes in amphibious vehicles.To address this gap in predicting attitudes near extreme inclination points,this study introduces a novel loss function,termed generalized extreme value loss.Subsequently,a deep learning model for improved waterborne attitude prediction,termed iInformer,was developed using a Transformer-based approach.During the embedding phase,a text prototype is created based on the vehicle’s operation log data is constructed to help the model better understand the vehicle’s operating environment.Data segmentation techniques are used to highlight local data variation features.Furthermore,to mitigate issues related to poor convergence and slow training speeds caused by the extreme value loss function,a teacher forcing mechanism is integrated into the model,enhancing its convergence capabilities.Experimental results validate the effectiveness of the proposed method,demonstrating its ability to handle data imbalance challenges.Specifically,the model achieves over a 60%improvement in root mean square error under extreme value conditions,with significant improvements observed across additional metrics. 展开更多
关键词 Amphibious vehicle Attitude prediction Extreme value loss function Enhanced transformer architecture External information embedding
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Influence of mold wall thickness on morphologies of defect band in high-pressure die casting technology
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作者 Zhen-yu Sun Wen-bo Yu +4 位作者 Jun-jie Li Wei-chen Zheng Guang-rui Wang Jian-ru Fang Shou-mei Xiong 《China Foundry》 2026年第1期31-36,共6页
In order to investigate the effect of die wall thickness on morphologies of defect band,a stepped mold with a wall thickness of 5 mm,4 mm,3 mm,2 mm,and 1 mm was designed to carry out high pressure die casting experime... In order to investigate the effect of die wall thickness on morphologies of defect band,a stepped mold with a wall thickness of 5 mm,4 mm,3 mm,2 mm,and 1 mm was designed to carry out high pressure die casting experiments with AlSi10 MgMn alloy.For castings with wall thickness of 2-4 mm,the ratio of the mean defect band width(w)and mean grain size(d)in the defect band(w/d)ranges 7-18,while it increases to 24.47 for the 5 mm-thick casting.This difference is related with the filling speed and the distribution of externally solidified crystals(ESCs).The mold flow analysis indicates that the filling speed decreases from 25.41 m·s^(-1)to 11.07 m·s^(-1)when wall thickness increases from 2 mm to 5 mm.Due to the decreasing filling speed along the wall thickness,ESCs gradually diffuse from the center to the defect band,which keep the shear strength in the defect band at a high-level during filling.Meanwhile,the shear strength generated during the filling also decreases as the shear rate drops.Finally,the defect bands in the 5 mm-thick region become widen and indistinct,and the porosity is as high as 5.25%. 展开更多
关键词 AlSi10MgMn high pressure die casting defect band mold flow analysis externally solidified crystals
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A review of electroslag remelting composite technologies
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作者 Yu Wang Yan-chun Lou +5 位作者 Fang Wang Heng Cao Yun-bao Gao Ling Zhao Zhi Han Meng Li 《China Foundry》 2026年第1期1-19,共19页
Electroslag remelting(ESR) is an important metallurgical process for producing high-purity materials with homogeneous compositions and sound microstructures,and its typical products are ingots or simple castings.The c... Electroslag remelting(ESR) is an important metallurgical process for producing high-purity materials with homogeneous compositions and sound microstructures,and its typical products are ingots or simple castings.The core principle involves the resistive melting of a consumable electrode within a slag pool,followed by the refining of molten metal droplets as they traverse the slag,and subsequent sequential solidification in a water-cooled mold.However,conventional ESR processes face limitations in producing large or complex-shaped components,enhancing production efficiency,achieving highly specialized microstructures,and meeting ultra-high purity demands for advanced applications.Advanced composite ESR technologies have been developed to overcome these limitations by innovatively modifying key process aspects.For instance,electrode systems are improved using vibration,rotation,or multiple electrodes.Enhanced mold design and solidification control are achieved through techniques including conductive molds,mold rotation,and ingot withdrawal.Precise control of the process is realized through the use of protective gas,vacuum,or elevated pressure,as well as the application of external fields such as magnetic fields or ultrasonic vibration.This review comprehensively summarizes these advanced techniques,examining their principles and characteristics,and discussing their specific advantages and challenges. 展开更多
关键词 electroslag remelting(ESR) composite electroslag technology near-net shape casting high purity materials process modification external field assisted casting
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Research status of high efficiency deep penetration welding of medium-thick plate titanium alloy:A review 被引量:4
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作者 Zhihai Dong Ye Tian +4 位作者 Long Zhang Tong Jiang Dafeng Wang Yunlong Chang Donggao Chen 《Defence Technology(防务技术)》 2025年第3期178-202,共25页
Titanium alloy has the advantages of high strength,strong corrosion resistance,excellent high and low temperature mechanical properties,etc.,and is widely used in aerospace,shipbuilding,weapons and equipment,and other... Titanium alloy has the advantages of high strength,strong corrosion resistance,excellent high and low temperature mechanical properties,etc.,and is widely used in aerospace,shipbuilding,weapons and equipment,and other fields.In recent years,with the continuous increase in demand for medium-thick plate titanium alloys,corresponding welding technologies have also continued to develop.Therefore,this article reviews the research progress of deep penetration welding technology for medium-thick plate titanium alloys,mainly covering traditional arc welding,high-energy beam welding,and other welding technologies.Among many methods,narrow gap welding,hybrid welding,and external energy field assistance welding all contribute to improving the welding efficiency and quality of medium-thick plate titanium alloys.Finally,the development trend of deep penetration welding technology for mediumthick plate titanium alloys is prospected. 展开更多
关键词 Titanium alloy Deep penetration welding Narrow gap welding Hybrid welding External energy field assistance welding
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Dynamic Behavior of a Pipe Conveying a Gas-Liquid Two-Phase Flow Under External Excitations 被引量:1
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作者 FU Guang-ming WANG Xiao +4 位作者 JIAO Hui-lin WANG Bo-ying SHAN Zheng-feng SUN Bao-jiang SU Jian 《China Ocean Engineering》 2025年第5期822-838,共17页
This work investigated the dynamic behavior of vertical pipes conveying gas-liquid two-phase flow when subjected to external excitations at both ends.Even with minimal excitation amplitude,resonance can occur when the... This work investigated the dynamic behavior of vertical pipes conveying gas-liquid two-phase flow when subjected to external excitations at both ends.Even with minimal excitation amplitude,resonance can occur when the excitation frequency aligns with the natural frequency of the pipe,significantly increasing the degree of operational risk.The governing equation of motion based on the Euler-Bernoulli beam is derived for the relative deflection with stationary simply supported ends,with the effects of the external excitations represented by source terms distributed along the pipe length.The fourth-order partial differential equation is solved via the generalized integral transform technique(GITT),with the solution successfully verified via comparison with results in the literature.A comprehensive analysis of the vibration phenomena and changes in the motion state of the pipe is conducted for three classes of external excitation conditions:same frequency and amplitude(SFSA),same frequency but different amplitudes(SFDA),and different frequencies and amplitudes(DFDA).The numerical results show that with increasing gas volume fraction,the position corresponding to the maximum vibration displacement shifts upward.Compared with conditions without external excitation,the vibration displacement of the pipe conveying two-phase flow under external excitation increases significantly.The frequency of external excitation has a significant effect on the dynamic behavior of a pipe conveying two-phase flow. 展开更多
关键词 pipe conveying fluid integral transform two-phase flow external excitations dynamic response forced vibrations
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Effect of Percutaneous Catheterization and Negative Pressure Drainage in the Treatment of Giant Pancreatic Pseudocyst 被引量:1
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作者 Shenglin You Hankun Yuan +5 位作者 Xijuan Tan Qiyi Luo Libai Lu Zongjiang Luo Yuan Lu Jianchu Wang 《Journal of Biosciences and Medicines》 2025年第1期77-83,共7页
Bcakground: Pancreatic pseudocyst (PPC) is a common complication arising from acute or chronic pancreatitis, trauma, or pancreatic duct obstruction. When acute fluid collection persists for 4 - 6 weeks and is encapsul... Bcakground: Pancreatic pseudocyst (PPC) is a common complication arising from acute or chronic pancreatitis, trauma, or pancreatic duct obstruction. When acute fluid collection persists for 4 - 6 weeks and is encapsulated by a fibrous wall, it is classified as a pancreatic pseudocyst. While PPC is generally asymptomatic in many patients, it can manifest with persistent abdominal pain, dyspepsia, intra-cystic infection, and potentially lead to gastrointestinal obstruction in some cases. Although smaller PPCs may resolve spontaneously, larger PPCs tend to be refractory to absorption and often necessitate surgical intervention to prevent complications such as intracystic hemorrhage. Objective: To explore the efficacy of percutaneous catheterization with negative pressure in the treatment of large pancreatic pseudocysts. Methods: The cases of large pancreatic pseudocysts treated in our hospital from 2004 to 2022 were retrospectively collected, and the general condition, operation time, drainage time, feeding time, postoperative complications, hospital stay, cost and follow-up of the patients were analyzed. Results: A total of 132 patients with large pancreatic pseudocysts were collected. The average operation time was 32.4 ± 2.1 min;The retention time of the drainage tube was 30 ± 1.8 days in the percutaneous negative pressure drainage group;The postoperative feeding time was no fasting after local anesthesia drainage;Postoperative complications (bleeding, infection, pancreatic leakage, recurrence, anastomotic leakage, etc.): Two of the 132 patients had recurrent cysts, which were cured by re-puncture and negative pressure drainage. The length of hospital stay was 6 ± 1.1 days;The cost was 11,200 ± 1300 yuan;Follow-up: The follow-up time ranged from 1 to 3 years, and the patients had no discomfort. Conclusion: Percutaneous catheterization and negative pressure drainage can effectively treat large pancreatic pseudocysts. Compared with other treatment methods, it is simple and effective, the postoperative recovery of patients is faster, the physical damage is less, the hospital stay is shorter, and the cost is lower. 展开更多
关键词 Giant Pancreatic Pseudocyst Percutaneous External Drainage Treatment Method
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Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy
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作者 Junjie Li Wenbo Yu +5 位作者 Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei Xiong 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期147-153,共7页
High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile industry.Mg can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress aro... High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile industry.Mg can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated die-castings.Herein,the development of non-heat treatment Al alloys is becoming the hot topic.In addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of castings.To achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and Ce.Their influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic simulation.Our results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased porosity.Meanwhile,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical properties.Subsequent introduction of Ce resulted in the poisoning effect and reduced mechanical properties. 展开更多
关键词 aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment
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Nonlinear Dynamic Modeling of Steel Catenary Risers with Varying Curvatures Under Internal Flow and External Current Excitation 被引量:1
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作者 LI Fang-qiu CHENG Hao +4 位作者 LIU Miao-er LI Xin-xin AN Chen LU Hai-long LU Zhao-kuan 《China Ocean Engineering》 2025年第5期904-916,共13页
As oil and gas exploration moves into deeper waters,marine risers are subjected to increasingly complex service conditions,including vessel motions,ocean currents,seabed-soil interactions,and internal flow effects.Thi... As oil and gas exploration moves into deeper waters,marine risers are subjected to increasingly complex service conditions,including vessel motions,ocean currents,seabed-soil interactions,and internal flow effects.This work establishes a dynamic behavior model of steel catenary risers(SCRs)with varying curvatures subjected to internal flow and external currents and considers the effects of pipe-soil interactions on the curvature profile.The governing equation is solved via the generalized integral transform technique(GITT),which yields a semi-analytical solution of a high-order nonlinear partial differential equation.Parametric studies are then performed to analyze the effects of varying curvature on the vibration frequency and amplitude of SCRs.The vibration frequency and amplitude increase with the touchdown angle and hang-off angle,although the effect of the hang-off angle is negligible.Additionally,as the curvature increases along the centerline axis,the position of the maximum amplitude of the SCR moves upward. 展开更多
关键词 steel catenary riser(SCR) CURVATURE generalized integral transform technique(GITT) dynamic behav-ior internal flow and external current
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Experimental Observing Damage Evolution in Cement Pastes Exposed to External Sulfate Attack by in situ X-ray Computed Tomography
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作者 WU Min CAO Kailei +4 位作者 XIAO Weirong YU Zetai CAO Jierong DING Qingjun LI Jinhui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期164-170,共7页
The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an ... The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an X-ray computed tomography(X-ray CT)was used,i e,the tomography system of Zeiss Xradia 510 versa.The results indicate that X-CT can monitor the development process and distribution characteristics of the internal cracks of cement pastes under ESA with attack time.In addition,the C3A content in the cement significantly affects the damage mode of cement paste specimens during sulfate erosion.The damage of ordinary Portland cement(OPC)pastes subjected to sulfate attack with high C3A content are severe,while the damage of sulfate resistant Portland cement(SRPC)pastes is much smaller than that of OPC pastes.Furthermore,a quadratic function describes the correlation between the crack volume fraction and development depth for two cement pastes immermed in sulfate solution. 展开更多
关键词 CONCRETE external sulfate attack damage evolution situ X-ray computed tomography
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Effect of external and internal cues on core muscle activation during the Sahrmann five-level core stability test
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作者 Skyla Stifter Jessie McCaffrey +2 位作者 Tyler Nichols Ayse Ozcan Edeer Justine Ward 《World Journal of Methodology》 2025年第1期95-104,共10页
BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of cor... BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of core muscle activation and a person's ability to stabilize the lumbopelvic complex.Preparatory cues and images can be used to increase the activation of these muscles.To attain optimal movement patterns,it will be necessary to determine what cueing will give the most effective results for core stability.AIM To investigate the effects of external and internal cues on core muscle activation during the Sahrmann five-level core stability test.METHODS Total 68 participants(21.83±3.47 years)were randomly allocated to an external(n=35)or internal cue group(n=33).Participants performed the Sahrmann fivelevel core stability test without a cue as baseline and the five-level stability exercises with an internal or external cue.External cue group received a pressure biofeedback unit(PBU),and the internal cue group received an audio cue.A Delsys Trigno^(TM)surface electromyography unit was used for muscle activation from the rectus abdominis,external oblique,and transverse abdominis/internal oblique muscles.RESULTS Linear mixed effects model analysis showed that cueing had a significant effect on core muscle activation(P=0.001);however,there was no significant difference between cue types(internal or external)(P=0.130).CONCLUSION Both external and internal cueing have significant effects on core muscle activation during the Sahrmann five-level core stability test and the PBU does not create higher muscle activation than internal cueing. 展开更多
关键词 External cue Internal cue Muscle activation Core muscles Lumbopelvic stability Pressure biofeedback unit
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Major injury of the external iliac artery during robotic nephroureterectomy:Examining the surgical management and unexpected pathology finding
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作者 Riccardo Bertolo Luca Roggero +11 位作者 Claudio Brancelli Giovanni Corghi Filippo Migliorini Alessandro Veccia Luca Mezzetto Gian Franco Veraldi Anna Caliò Matteo Brunelli Guido Martignoni Antonio Benito Porcaro Maria Angela Cerruto Alessandro Antonelli 《Asian Journal of Urology》 2025年第2期275-277,共3页
Dear Editor,We aimed to describe the management of the intraoperative injury of the right external iliac artery that occurred during robot-assisted right nephroureterectomy with bladder cuff excision.Surgery was sched... Dear Editor,We aimed to describe the management of the intraoperative injury of the right external iliac artery that occurred during robot-assisted right nephroureterectomy with bladder cuff excision.Surgery was scheduled for suspected urothelial carcinoma of the distal ureter in a 60-year-old woman.The patient involved in the present research signed a dedicated form to consent to the publication of images and/or information about her.Past medical history included Brugada syndrome diagnosed in 2015,and hypercholesterolemia.Past surgical history included one cesarean section only.Family history included ovarian cancer(sister),colorectal cancer(mother),and kidney cancer(father). 展开更多
关键词 urothelial carcinoma right external iliac artery external iliac artery injury dedicated form unexpected pathology brugada syndrome surgical management robotic nephroureterectomy
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Exploration of evaluation criteria based on the biological variation in the external quality assessment for basic semen analysis in China
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作者 Xi-Yan Wu Jin-Chun Lu +6 位作者 Xin-Hua Peng Jing-Liang He Dao Wang Cong-Ling Dai Wen-Bing Zhu Gang Liu Wei-Na Li 《Asian Journal of Andrology》 2025年第5期621-626,共6页
This study explores whether the current external quality assessment(EQA)level and acceptable bias for basic semen analysis in China are clinically useful.We collected data of semen EQA from Andrology laboratories in t... This study explores whether the current external quality assessment(EQA)level and acceptable bias for basic semen analysis in China are clinically useful.We collected data of semen EQA from Andrology laboratories in the Hunan Province(China)in 2022 and searched for data in the published literature from January2000 to December 2023 in China.On the basis of these data,we analyzed the coefficients of variation and acceptable biases of different quality control materials for basic semen analysis through robust statistics.We compared these findings with quality specifications based on biological variation from optimal,desirable,and minimum levels of bias to seek a unified and more suitable semen EQAbias evaluation standard for China's national conditions.Different sources of semen quality control material exhibited considerable variation in acceptable biases among laboratories,ranging from 8.2%to 56.9%.A total of 50.0% of the laboratories met the minimum quality specifications for progressive motility(PR),whereas 100.0%and 75.0%of laboratories met only the minimum quality specifications for sperm concentration and total motility(nonprogressive[NP]+PR),respectively.The Z value for sperm concentration and PR+NP was equivalent to the desirable performance specification,whereas the Z value for PR was equivalent only to the minimum performance specification.This study highlights the feasibility of operating external quality assessment schemes for basic semen analysis using quality specifications based on biological variation.These specifications should be unified among external quality control(EQC)centers based on biological variation. 展开更多
关键词 acceptable bias biological variation external quality assessment(EQA) external quality control(EQC) semen testing
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Comparison of the quality of chest compressions during cardiopulmonary resuscitation with two models of automated external defibrillators:a manikin-based randomized trial
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作者 Arnaud Gaillard Cécile Ricard +1 位作者 Guillaume Berthet Vincent Peigne 《World Journal of Emergency Medicine》 2025年第4期374-377,共4页
Basic life support for cardiac arrest associates cardiopulmonary resuscitation(CPR)and defibrillation.CPR relies on chest compressions(CC)and ventilation.Current guidelines on CPR recommend a depth of 5-6 cm at a rhyt... Basic life support for cardiac arrest associates cardiopulmonary resuscitation(CPR)and defibrillation.CPR relies on chest compressions(CC)and ventilation.Current guidelines on CPR recommend a depth of 5-6 cm at a rhythm of 100-120 times/min for CC.[1,2]Interruptions of the CC must be as short as possible and are related to ventilation,defibrillation and turnover of the rescuers.Most of the automated external defibrillators(AEDs)require interruptions of the CC to perform rhythm analysis.Among the numerous marketed models of AEDs,some provide real-time feedback about the quality of the CC. 展开更多
关键词 cardiopulmonary resuscitation cpr chest compressions cc cardiopulmonary resuscitation automated external defibrillators aeds require rhythm analysisamong chest compressions automated external defibrillators manikin based randomized trial
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