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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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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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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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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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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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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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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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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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Continuously adjustable mechanical metamaterial based on planetary gear trains and external meshing gears
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作者 Shuai MO Xu TANG +2 位作者 Keren CHEN H.HOUJOH Wei ZHANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第2期233-252,共20页
The metamaterial based on external meshing gears(MEG)is designed based on the principle of external meshing gear transmission.Based on the meshing transmission principle of external meshing gears and planetary gear tr... The metamaterial based on external meshing gears(MEG)is designed based on the principle of external meshing gear transmission.Based on the meshing transmission principle of external meshing gears and planetary gear trains,the internal and external gear rings are designed.Based on the internal and external gear rings,the metamaterial based on inner and outer planetary gear trains(MIP)is designed to study the shear modulus,Young's modulus,and amplitude-frequency characteristics of the metamaterial based on gears at different angles.The effects of the number of planetary gears on the physical characteristics of the MIP are studied.The results show that the MEG can be continuously adjusted by adjusting the shear modulus and Young's modulus due to its meshing characteristics.With the same number of gears,the adjustment range of the MIP is larger than the adjustment range of the MEG.When the number of planetary gears increases,the adjustment range of the MIP decreases.Moreover,when the metamaterial based on gears rotates,the harmonic response changes with the change of the angle. 展开更多
关键词 METAMATERIAL ADJUSTABLE EXTERNAL inner and outer planetary gear train
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Wake instability of a fixed spherical droplet with a high drop-to-fluid viscosity ratio
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作者 Pengyu Shi Eric Climent Dominique Legendre 《Acta Mechanica Sinica》 2025年第7期138-148,共11页
Direct numerical simulations of a uniform flow past a fixed spherical droplet are performed to investigate the parameter range within which the axisymmetric flow becomes unstable due to an external flow bifurcation.Th... Direct numerical simulations of a uniform flow past a fixed spherical droplet are performed to investigate the parameter range within which the axisymmetric flow becomes unstable due to an external flow bifurcation.The hydrodynamics is governed by three dimensionless parameters:the viscosity ratioμ*,the external Reynolds numbers Re^(e),and internal Reynolds numbers Re^(i),respectively.The drop-to-fluid density ratio is related to these parameters asρ*=μ*Re^(i)/Re^(e).This study focuses on highly viscous droplets withμ*≥5,where wake instability is driven by the vorticity flux transferred from the droplet surface into the surrounding fluid.By analysing the wake structure,we confirm that the onset of the external bifurcation is linked to the tilting of the azimuthal vorticityωϕ,in the wake and that the bifurcation occurs once the isocontours ofωϕalign nearly perpendicular to the symmetry axis.We propose an empirical criterion for predicting the onset of the external bifurcation,formulated in terms of the maximum vorticity on the external side of the droplet surface.This criterion is applicable for sufficiently high Re^(i) and holds over a wide range ofμ*and Re^(e).Additionally,we examine the bifurcation sequence for two specific external Reynolds numbers,Re^(e)=300 and Re^(e)=500,and show that,beyond a critical viscosity ratio,the axisymmetric wake first transitions to a steady planar-symmetric state before undergoing a secondary Hopf bifurcation.Finally,we highlight the influence of Re^(i) on external bifurcation and show that,at moderate Re^(i),wake instability may set in at a lower vorticity threshold than predicted by our criterion.These findings provide new insights into the external flow bifurcation of viscous droplets. 展开更多
关键词 Spherical droplet External flow bifurcation External surface vorticity
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Clinical Study on External Application of Scorzonera Herpes Ointment Combined with Methylprednisolone Sodium Succinate for Injection in the Treatment of Herpes Zoster Oticus
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作者 Yi LI Guangke WANG +4 位作者 Wei YUE Yage ZHANG Haolei HU Peimei XING Dexin SHEN 《Medicinal Plant》 2025年第3期46-49,共4页
[Objectives]To observe the clinical efficacy of external application of Scorzonera Herpes Ointment combined with Methylprednisolone Sodium Succinate for Injection in the treatment of herpes zoster oticus(HZO).[Methods... [Objectives]To observe the clinical efficacy of external application of Scorzonera Herpes Ointment combined with Methylprednisolone Sodium Succinate for Injection in the treatment of herpes zoster oticus(HZO).[Methods]A total of 100 HZO patients admitted to the 988 th Hospital of the Joint Logistics Support Force and Henan Provincial People's Hospital from June 2021 to June 2023 were selected.They were divided into a treatment group and a control group using a random number table method,with 50 cases in each group.Both groups received Methylprednisolone Sodium Succinate for Injection.Additionally,the treatment group was treated with external application of Scorzonera Herpes Ointment,while the control group received acyclovir ointment.Both groups were treated for 10 d.The comparisons included clinical efficacy,total symptom and sign scores,pain level[Visual Analogue Scale(VAS)],time for erythema reduction,cessation of blister formation,scab formation,and scab shedding,incidence of post-herpetic neuralgia(PHN),air conduction hearing threshold,and air-bone gap.[Results]After 10 d of treatment,the total effective rate was 98.00%(49/50)in the treatment group and 84.00%(42/50)in the control group,with a statistically significant difference between the two groups(P<0.05).After 10 d of treatment,the total symptom and sign scores and VAS scores of both groups decreased compared to those before treatment.The treatment group had significantly lower scores than the control group(P<0.05).The treatment group showed significantly shorter time for erythema reduction,cessation of blister formation,scab formation,and scab shedding compared to the control group(P<0.05).During the 1-month follow-up after treatment,no PHN cases occurred in the treatment group,while the incidence of PHN in the control group was 24.00%(12/50),showing a statistically significant difference(P<0.05).After 10 d of treatment,both groups showed reduced air conduction hearing thresholds,and the treatment group exhibited significantly lower air conduction thresholds and air-bone gaps compared to the control group(P<0.05).No statistically significant difference was observed in the air-bone gap before and after treatment in the control group(P>0.05).[Conclusions]The combination of external application of Scorzonera Herpes Ointment and Methylprednisolone Sodium Succinate for Injection can alleviate pain and other discomforts,reduce PHN incidence,shorten disease duration,and improve hearing in HZO patients. 展开更多
关键词 HERPES ZOSTER oticus Scorzonera HERPES OINTMENT External application METHYLPREDNISOLONE Sodium Succinate for INJECTION Post-herpetic NEURALGIA Hearing
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Effectiveness of the induced membrane technique in aseptic and infected long-bone defect management: Are there any differences?
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作者 Alexander L Shastov Sergey N Kolchin Tatiana A Malkova 《World Journal of Orthopedics》 2025年第7期16-28,共13页
Management of post-traumatic long-bone defects remains relevant and cha-llenging despite the rapid development of approaches to their treatment.Do-minant positions are occupied by the Ilizarov method,bone autogenous g... Management of post-traumatic long-bone defects remains relevant and cha-llenging despite the rapid development of approaches to their treatment.Do-minant positions are occupied by the Ilizarov method,bone autogenous grafting and the Masquelet induced membrane technique(IMT).The IMT is aimed at reducing extensive defect treatment duration and for this reason has gained great popularity.However,the assessment of its effectiveness is difficult due to a limited number of clinical series.The varying clinical manifestations of bone defect severity do not allow a comprehensive evaluation of IMT effectiveness.One of them is infection in the defect area.The purpose of our literature review is an analysis of studies on IMT application in infected vs non-infected long-bone defects of the lower extremities published over the last 10 years.It focuses on the investigation of similarities and fundamental differences in the need for antibiotics,timing of spacer fixation,methods of collecting donor bone and fixators used for consolidation.The studies show that the IMT has been globally used in aseptic and osteomyelitic defects due to its clinical effectiveness.Authors’variations and improvements in its practical implementation indicate the ongoing development and the interest of researchers in this technique. 展开更多
关键词 Long bone NONUNION Defect Induced membrane technique Infection Spacer Intramedullary nail External fixator OSTEOMYELITIS
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Performance Evaluation of Damaged T-Beam Bridges with External Prestressing Reinforcement Based on Natural Frequencies
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作者 Menghui Hao Shanshan Zhou +4 位作者 Yongchao Han Zhanwei Zhu Qiang Yang Panxu Sun Jiajun Fan 《Structural Durability & Health Monitoring》 2025年第2期399-415,共17页
As an evaluation index,the natural frequency has the advantages of easy acquisition and quantitative evaluation.In this paper,the natural frequency is used to evaluate the performance of external cable reinforced brid... As an evaluation index,the natural frequency has the advantages of easy acquisition and quantitative evaluation.In this paper,the natural frequency is used to evaluate the performance of external cable reinforced bridges.Numerical examples show that compared with the natural frequencies of first-order modes,the natural frequencies of higher-order modes are more sensitive and can reflect the damage situation and external cable reinforcement effect of T-beam bridges.For damaged bridges,as the damage to the T-beam increases,the natural frequency value of the bridge gradually decreases.When the degree of local damage to the beam reaches 60%,the amplitude of natural frequency change exceeds 10%for the first time.The natural frequencies of the firstorder vibration mode and higher-order vibration mode can be selected as indexes for different degrees of the damaged T-beam bridges.For damaged bridges reinforced with external cables,the traditional natural frequency of the first-order vibration mode cannot be used as the index,which is insensitive to changes in prestress of the external cable.Some natural frequencies of higher-order vibration modes can be selected as indexes,which can reflect the reinforcement effect of externally prestressed damaged T-beam bridges,and its numerical value increases with the increase of external prestressed cable force. 展开更多
关键词 Performance evaluation natural frequency T-beam bridge DAMAGE external cable reinforcement
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Response of Decadal Droughts on the Mongolian Plateau to External Forcings and Internal Variability over the Last Millennium
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作者 Guangyao HAO Weiyi SUN +2 位作者 Jian LIU Liang NING Mi YAN 《Advances in Atmospheric Sciences》 2025年第8期1715-1726,共12页
Since the mid-20th century,the Mongolian Plateau(MP)has experienced decadal droughts coupled with extreme heatwaves,severely affecting regional ecology and social development.However,the mechanisms behind these decada... Since the mid-20th century,the Mongolian Plateau(MP)has experienced decadal droughts coupled with extreme heatwaves,severely affecting regional ecology and social development.However,the mechanisms behind these decadalscale compound heatwavedrought events remain debated.Here,using reconstructions and simulations from the Community Earth System Model Last Millennium Ensemble,we demonstrate that,over the last millennium,decadal droughts on the MP occurred under both warm and cold conditions,differing from recent compound heatwavedrought events.We found that by examining temperature changes during these drought periods,the distinct influences of external forcings and internal variability can be simply and effectively distinguished.Specifically,colddry events were primarily driven by volcanic eruptions that weakened the East Asian summer monsoon and midlatitude westerlies,reducing moisture transport to the MP.In contrast,warmdry events were predominantly induced by internal variability,notably the negative phase of the Atlantic Multidecadal Oscillation and the expansion of the Barents Sea ice extent.The recent extreme compound event was probably influenced by the combined effects of anthropogenic forcings and internal variability.These findings deepen our understanding of how external forcings and internal variability affect decadal drought events on the MP and highlight that recent compound events are unprecedented in the context of the last millennium. 展开更多
关键词 decadal drought Mongolian Plateau temperature anomalies external forcings internal variability
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Catalytic conversion of biomass waste to methane without external hydrogen source
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作者 Wenbing Yu Xiaoqin Si +3 位作者 Mengjie Li Zhenggang Liu Rui Lu Fang Lu 《Chinese Journal of Catalysis》 2025年第4期246-255,共10页
Methane,the primary constituent of natural gas,shale gas,and flammable ice,serves as a crucial carbon-based energy source and chemical feedstock.Traditional gas reserves are universally acknowledged as limited and non... Methane,the primary constituent of natural gas,shale gas,and flammable ice,serves as a crucial carbon-based energy source and chemical feedstock.Traditional gas reserves are universally acknowledged as limited and non-renewable resources over an extended timespan stretching from decades to millennia.Biomethane,with its unique renewable properties,showcases remarkable development potential and presents a compelling supplement and even alternative for fossil fuel.Although catalytic hydrothermal processes appear as promising valorization routes to transfer biomass to sustainable methane,the safety and supply source of high-pressure hydrogen remain key factors restricting the widespread application.Herein,a catalytic approach without an external hydrogen source was developed to transform waste biomass resources into CH_(4)under the Ni-Mo catalyst.The total carbon yield of gas products reached up to 92.2%,of which the yield of methane and C2–C4 hydrocarbons were 44.9%and 3.0%,respectively.And it’s calculated that approximately 343.6 liters of CH_(4)could potentially be generated from 1 kilogram of raw biomass.Ni-based catalysts exhibited the robust activity in cleaving C–C and C–O bonds.And the introduction of an appropriate amount of molybdenum significantly enhanced catalytic performance of reforming and subsequent methanation reaction,likely due to the high adsorption capacity of highly dispersed Ni-Mo catalysts for carbon monoxide and hydrogen molecules,facilitating the methanation reaction.The pathway of catalytic methane production might be inferred that CO,H_(2)and a large number of oxygen-containing intermediates were formed via decarbonylation,dehydrogenation,and retro-aldol condensation reaction under hydrothermal condition.These intermediates then underwent the reforming reaction to generate H_(2)and CO_(2),ultimately forming CH_(4)through the methanation reaction. 展开更多
关键词 Waste biomass Ni-Mo catalyst METHANE HYDROGEN Without external hydrogen source
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