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Relationships between Quadriceps:Hamstring Strength Ratio and Lower Extremity Injuries in Netball Players
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作者 Henriette Hammill 《Open Journal of Applied Sciences》 2024年第4期1022-1033,共12页
Background: Netball is a popular sport. Due to high impact and quick movement, there is an enormous load on the lower extremities which increases the risk for injury. Aim: The aim of this study was to investigate the ... Background: Netball is a popular sport. Due to high impact and quick movement, there is an enormous load on the lower extremities which increases the risk for injury. Aim: The aim of this study was to investigate the relationship between the quadricep and hamstring strength and the prevalence of lower extremity injuries in netball players. Setting: Twenty-five female netball players (age: 20.8 ± 1.4 years) voluntarily participated. Methods: The Cybex Isokinetic dynamometer was used to determine concentric knee torques. Quadriceps:hamstring strength ratio was determined. Occurrence of lower extremity injuries was documented bi-weekly. Results: Medium effect sizes were noted for flexion torque:work for the left leg and for the quadriceps:hamstring ratio (≥60%) for the right leg. All the other measured variables have a small effect size. 18.75% of lower extremity injuries and ConQ:ConH of Conclusion: Injuries to the ankle and knee are especially common among netball players. Hamstring and quadriceps muscle asymmetry (>10%) were found to be a potential indicator of lower extremity injury. Contribution: This study highlights awareness on lower extremity injuries and the strength ratio between the quadriceps and hamstrings. This can aid coaches and netball players to lower the risk for injuries and thus improve individual- and team performance. 展开更多
关键词 Netball HAMSTRINGS QUadrICEPS Strength ratio Lower Extremity Injuries
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基于改进Ratio统计量的重尾AR(p)时间序列均值变点检验
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作者 张思 刘叶 金浩 《统计与决策》 CSSCI 北大核心 2024年第2期52-57,共6页
文章提出两个改进的Ratio统计量来研究重尾AR(p)时间序列均值变点检验问题,在原假设下推导了统计量的渐近分布,且在备择假设下证明了其一致性。由于重尾指数未知且难以估计,因此结合Wild Bootstrap重抽样方法来确定渐近分布的临界值;在... 文章提出两个改进的Ratio统计量来研究重尾AR(p)时间序列均值变点检验问题,在原假设下推导了统计量的渐近分布,且在备择假设下证明了其一致性。由于重尾指数未知且难以估计,因此结合Wild Bootstrap重抽样方法来确定渐近分布的临界值;在均值变点存在的情形下,给出了变点位置的一致估计量。数值模拟结果表明:统计量的临界值均不受重尾指数和自回归系数的影响,其经验水平和经验势均取得满意的效果;尤其在原假设下,积分型Ratio统计量的经验水平表现出更好的稳健性,而在备择假设下,最值型Ratio统计量则具备更好的显著性。最后,基于一组股票数据,从实际应用角度进一步阐明所提方法的有效性和可行性。 展开更多
关键词 重尾序列 ratio统计量 均值变点 Wild Bootstrap
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灵菌红素对耐阿霉素人乳腺癌细胞MCF-7/ADR的作用研究
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作者 林俊标 赵嘉怡 +1 位作者 高焯巧 马艳 《广东药科大学学报》 CAS 2024年第4期84-90,共7页
目的探讨灵菌红素对耐阿霉素人乳腺癌细胞MCF-7/ADR的作用。方法采用平板发酵粘质沙雷氏菌WA12-1-18生产灵菌红素,CCK-8测定灵菌红素的体外活性及MCF-7/ADR的耐药指数。构建裸鼠皮下移植瘤模型,灵菌红素高、低剂量组分别腹腔注射5.0、2.... 目的探讨灵菌红素对耐阿霉素人乳腺癌细胞MCF-7/ADR的作用。方法采用平板发酵粘质沙雷氏菌WA12-1-18生产灵菌红素,CCK-8测定灵菌红素的体外活性及MCF-7/ADR的耐药指数。构建裸鼠皮下移植瘤模型,灵菌红素高、低剂量组分别腹腔注射5.0、2.5 mg/kg灵菌红素,生理盐水对照位腹腔注射等体积生理盐水,每4天1次,连续用药24 d,观察移植瘤的体积、质量及裸鼠体质量,HE染色观察移植瘤组织及裸鼠主要脏器的病理情况,免疫组织化学检测移植瘤Ki-67的表达。结果获得的灵菌红素质量分数为95.18%,对MCF-7和MCF-7/ADR的IC50分别为0.484μg/mL和0.264μg/mL。MCF-7/ADR耐药指数13,符合细胞耐药株的要求。灵菌红素处理组裸鼠移植瘤增长速度较生理盐水组慢,肿瘤细胞排列稀疏,核小且着色较浅,Ki-67染色后棕色明显减少。灵菌红素2.5 mg/kg组和灵菌红素5 mg/kg组,在荷MCF-7/ADR裸鼠中抑瘤率分别为37.23%和53.72%。另外,各组裸鼠体质量差异无统计学意义,主要脏器无明显病理变化。结论灵菌红素可抑制裸鼠体内耐阿霉素人乳腺癌细胞MCF-7/ADR的生长,对心、肝、脾、肺和肾等主要脏器无明显毒副作用,为灵菌红素在耐阿霉素乳腺癌的临床应用提供了实验依据。 展开更多
关键词 耐阿霉素人乳腺癌细胞MCF-7/adr 灵菌红素 裸鼠 移植瘤
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Yields,growth and water use under chemical topping in relations to row configuration and plant density in drip-irrigated cotton 被引量:1
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作者 Wang Xuejiao Hu Yanping +10 位作者 Ji Chunrong Chen Yongfan Sun Shuai Zhang Zeshan Zhang Yutong Wang Sen Yang Mingfeng Ji Fen Guo Yanyun Li Jie Zhang Lizhen 《Journal of Cotton Research》 CAS 2024年第2期123-136,共14页
Background Water deficit is an important problem in agricultural production in arid regions.With the advent of wholly mechanized technology for cotton planting in Xinjiang,it is important to determine which planting m... Background Water deficit is an important problem in agricultural production in arid regions.With the advent of wholly mechanized technology for cotton planting in Xinjiang,it is important to determine which planting mode could achieve high yield,fiber quality and water use efficiency(WUE).This study aimed to explore if chemical topping affected cotton yield,quality and water use in relation to row configuration and plant densities.Results Experiments were carried out in Xinjiang China,in 2020 and 2021 with two topping method,manual topping and chemical topping,two plant densities,low and high,and two row configurations,i.e.,76 cm equal rows and 10+66 cm narrow-wide rows,which were commonly applied in matching harvest machine.Chemical topping increased seed cotton yield,but did not affect cotton fiber quality comparing to traditional manual topping.Under equal row spacing,the WUE in higher density was 62.4%higher than in the lower one.However,under narrow-wide row spacing,the WUE in lower density was 53.3%higher than in higher one(farmers’practice).For machine-harvest cotton in Xinjiang,the optimal row configuration and plant density for chemical topping was narrow-wide rows with 15 plants m-2 or equal rows with 18 plants m-2.Conclusion The plant density recommended in narrow-wide rows was less than farmers’practice and the density in equal rows was moderate with local practice.Our results provide new knowledge on optimizing agronomic managements of machine-harvested cotton for both high yield and water efficient. 展开更多
关键词 Yield components Fiber quality TRANSPIratioN Water use efficiency Heat ratio method(HRM)
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A gated recurrent unit model to predict Poisson’s ratio using deep learning 被引量:1
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作者 Fahd Saeed Alakbari Mysara Eissa Mohyaldinn +4 位作者 Mohammed Abdalla Ayoub Ibnelwaleed A.Hussein Ali Samer Muhsan Syahrir Ridha Abdullah Abduljabbar Salih 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期123-135,共13页
Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to spe... Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to specific data ranges with an average absolute percentage relative error(AAPRE)of more than 10%.The published gated recurrent unit(GRU)models do not consider trend analysis to show physical behaviors.In this study,we aim to develop a GRU model using trend analysis and three inputs for predicting n s based on a broad range of data,n s(value of 0.1627-0.4492),bulk formation density(RHOB)(0.315-2.994 g/mL),compressional time(DTc)(44.43-186.9 μs/ft),and shear time(DTs)(72.9-341.2μ s/ft).The GRU model was evaluated using different approaches,including statistical error an-alyses.The GRU model showed the proper trends,and the model data ranges were wider than previous ones.The GRU model has the largest correlation coefficient(R)of 0.967 and the lowest AAPRE,average percent relative error(APRE),root mean square error(RMSE),and standard deviation(SD)of 3.228%,1.054%,4.389,and 0.013,respectively,compared to other models.The GRU model has a high accuracy for the different datasets:training,validation,testing,and the whole datasets with R and AAPRE values were 0.981 and 2.601%,0.966 and 3.274%,0.967 and 3.228%,and 0.977 and 2.861%,respectively.The group error analyses of all inputs show that the GRU model has less than 5% AAPRE for all input ranges,which is superior to other models that have different AAPRE values of more than 10% at various ranges of inputs. 展开更多
关键词 Static Poisson’s ratio Deep learning Gated recurrent unit(GRU) Sand control Trend analysis Geomechanical properties
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Serum cystatin C,monocyte/high-density lipoprotein-C ratio,and uric acid for the diagnosis of coronary heart disease and heart failure 被引量:1
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作者 Ming Li Da-Hao Yuan +2 位作者 Zhi Yang Teng-Xiang Luw Xiao-Biao Zou 《World Journal of Clinical Cases》 SCIE 2024年第18期3461-3467,共7页
BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.Howeve... BACKGROUND Coronary heart disease(CHD)and heart failure(HF)are the major causes of morbidity and mortality worldwide.Early and accurate diagnoses of CHD and HF are essential for optimal management and prognosis.However,conventional diagnostic methods such as electrocardiography,echocardiography,and cardiac biomarkers have certain limitations,such as low sensitivity,specificity,availability,and cost-effectiveness.Therefore,there is a need for simple,noninvasive,and reliable biomarkers to diagnose CHD and HF.AIM To investigate serum cystatin C(Cys-C),monocyte/high-density lipoprotein cholesterol ratio(MHR),and uric acid(UA)diagnostic values for CHD and HF.METHODS We enrolled 80 patients with suspected CHD or HF who were admitted to our hospital between July 2022 and July 2023.The patients were divided into CHD(n=20),HF(n=20),CHD+HF(n=20),and control groups(n=20).The serum levels of Cys-C,MHR,and UA were measured using immunonephelometry and an enzymatic method,respectively,and the diagnostic values for CHD and HF were evaluated using receiver operating characteristic(ROC)curve analysis.RESULTS Serum levels of Cys-C,MHR,and UA were significantly higher in the CHD,HF,and CHD+HF groups than those in the control group.The serum levels of Cys-C,MHR,and UA were significantly higher in the CHD+HF group than those in the CHD or HF group.The ROC curve analysis showed that serum Cys-C,MHR,and UA had good diagnostic performance for CHD and HF,with areas under the curve ranging from 0.78 to 0.93.The optimal cutoff values of serum Cys-C,MHR,and UA for diagnosing CHD,HF,and CHD+HF were 1.2 mg/L,0.9×10^(9),and 389μmol/L;1.4 mg/L,1.0×10^(9),and 449μmol/L;and 1.6 mg/L,1.1×10^(9),and 508μmol/L,respectively.CONCLUSION Serum Cys-C,MHR,and UA are useful biomarkers for diagnosing CHD and HF,and CHD+HF.These can provide information for decision-making and risk stratification in patients with CHD and HF. 展开更多
关键词 Serum cystatin C Monocyte/high-density lipoprotein-C ratio Uric acid Coronary heart disease Heart failure Risk stratification
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数智时代我国纠纷解决机制——从ADR到ODR
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作者 陈怡帆 聂洪涛 《科技智囊》 2024年第4期54-60,共7页
[研究目的]随着信息技术的不断完善,我国电子商务蓬勃发展。与此同时,网络纠纷的增长也随之而来。数智时代民事纠纷呈现出数量多、增速快、标的较小、解决周期短的特点。[研究方法]传统的诉讼解决机制已难以适应数智时代下我国网络纠纷... [研究目的]随着信息技术的不断完善,我国电子商务蓬勃发展。与此同时,网络纠纷的增长也随之而来。数智时代民事纠纷呈现出数量多、增速快、标的较小、解决周期短的特点。[研究方法]传统的诉讼解决机制已难以适应数智时代下我国网络纠纷的解决需要,“互联网+”技术的发展及“共建共治共享”网络空间治理格局的不断推进使得在线纠纷解决机制应运而生。我国的在线诉讼及智慧法院建设属于ODR机制在司法领域的应用,ODR突破了传统Online ADR的非诉解纷范畴,实现了司法诉讼的线上审判新模式。企业可以直接通过互联网端进行纠纷申报与处理,避免了线下冲突;平台可以在线收集消费者的投诉信息并进行分类处理,更加高效的掌握自家产品或服务面向市场过程中产生的问题,进而加强企业管理与质量监督,改善工作,有利于将企业的不利影响降到最低。在现实应用中,我国ODR机制仍存在立法缺失、ODR机制执行效率低下、消费者信任不足等一系列问题。[研究结论]对此,应在数智背景下完善关于ODR机制对消费者保护的立法规定、培养人民群众化解矛盾纠纷的新思维范式,促进线上纠纷解决机制的普及度,加强“电子信用”建设、完善保全与救济措施、提升ODR机制的平台建设与人才储备以更好促进我国ODR机制的良性发展。 展开更多
关键词 在线纠纷解决 ODR 在线调解 adr 多元纠纷解决机制
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Systemic immune-inflammation index,neutrophilto-lymphocyte ratio,and platelet-to-lymphocyte ratio in patients with type 2 diabetes at different stages of diabetic retinopathy
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作者 Ying Gao Rong-Xin Lu +6 位作者 Yun Tang Xin-Yi Yang Hu Meng Chang-Lin Zhao Yi-Lu Chen Feng Yan Qian Cao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第5期877-882,共6页
AIM:To investigate systemic immune-inflammation index(SII),neutrophil-to-lymphocyte ratio(NLR),and plateletto-lymphocyte ratio(PLR)levels in patients with type 2 diabetes at different stages of diabetic retinopathy(DR... AIM:To investigate systemic immune-inflammation index(SII),neutrophil-to-lymphocyte ratio(NLR),and plateletto-lymphocyte ratio(PLR)levels in patients with type 2 diabetes at different stages of diabetic retinopathy(DR).METHODS:This retrospective study included 141 patients with type 2 diabetes mellitus(DM):45 without diabetic retinopathy(NDR),47 with non-proliferative diabetic retinopathy(NPDR),and 49 with proliferative diabetic retinopathy(PDR).Complete blood counts were obtained,and NLR,PLR,and SII were calculated.The study analysed the ability of inflammatory markers to predict DR using receiver operating characteristic(ROC)curves.The relationships between DR stages and SII,PLR,and NLP were assessed using multivariate logistic regression.RESULTS:The average NLR,PLR,and SII were higher in the PDR group than in the NPDR group(P=0.011,0.043,0.009,respectively);higher in the NPDR group than in the NDR group(P<0.001 for all);and higher in the PDR group than in the NDR group(P<0.001 for all).In the ROC curve analysis,the NLR,PLR,and SII were significant predictors of DR(P<0.001 for all).The highest area under the curve(AUC)was for the PLR(0.929 for PLR,0.925 for SII,and 0.821 for NLR).Multivariate regression analysis indicated that NLR,PLR,and SII were statistically significantly positive and independent predictors for the DR stages in patients with DM[odds ratio(OR)=1.122,95%confidence interval(CI):0.200–2.043,P<0.05;OR=0.038,95%CI:0.018–0.058,P<0.05;OR=0.007,95%CI:0.001–0.01,P<0.05,respectively).CONCLUSION:The NLR,PLR,and SII may be used as predictors of DR. 展开更多
关键词 diabetic retinopathy neutrophil-tolymphocyte ratio platelet-to-lymphocyte ratio systemic immune-inflammation index
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Predictive Ability of Hypertriglyceridemic Waist,Hypertriglyceridemic Waist-to-Height Ratio,and Waist-to-Hip Ratio for Cardiometabolic Risk Factors Clustering Screening among Chinese Children and Adolescents
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作者 XIAO Tian Li YUAN Shu Qian +6 位作者 GAO Jing Yu Julien SBaker YANG Yi De WANG Xi Jie ZHENG Chan Juan DONG Yan Hui ZOU Zhi Yong 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第3期233-241,共9页
Objective Hypertriglyceridemic waist(HW),hypertriglyceridemic waist-to-height ratio(HWHtR),and waist-to-hip ratio(WHR)have been shown to be indicators of cardiometabolic risk factors.However,it is not clear which indi... Objective Hypertriglyceridemic waist(HW),hypertriglyceridemic waist-to-height ratio(HWHtR),and waist-to-hip ratio(WHR)have been shown to be indicators of cardiometabolic risk factors.However,it is not clear which indicator is more suitable for children and adolescents.We aimed to investigate the relationship between HW,HWHtR,WHR,and cardiovascular risk factors clustering to determine the best screening tools for cardiometabolic risk in children and adolescents.Methods This was a national cross-sectional study.Anthropometric and biochemical variables were assessed in approximately 70,000 participants aged 6–18 years from seven provinces in China.Demographics,physical activity,dietary intake,and family history of chronic diseases were obtained through questionnaires.ANOVA,χ2 and logistic regression analysis was conducted.Results A significant sex difference was observed for HWHtR and WHR,but not for HW phenotype.The risk of cardiometabolic health risk factor clustering with HW phenotype or the HWHtR phenotype was significantly higher than that with the non-HW or non-HWHtR phenotypes among children and adolescents(HW:OR=12.22,95%CI:9.54-15.67;HWHtR:OR=9.70,95%CI:6.93-13.58).Compared with the HW and HWHtR phenotypes,the association between risk of cardiometabolic health risk factors(CHRF)clustering and high WHR was much weaker and not significant(WHR:OR=1.14,95%CI:0.97-1.34).Conclusion Compared with HWHtR and WHR,the HW phenotype is a more convenient indicator with higher applicability to screen children and adolescents for cardiovascular risk factors. 展开更多
关键词 Hypertriglyceridemic waist Waist-to-hip ratio Children and adolescents China Hypertriglyceridemic waist-to-height ratio Cardiovascular risk factors
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Neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio:Markers predicting immune-checkpoint inhibitor efficacy and immune-related adverse events
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作者 Qiu-Yu Jiang Ru-Yi Xue 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期577-582,共6页
We conducted a comprehensive review of existing prediction models pertaining to the efficacy of immune-checkpoint inhibitor(ICI)and the occurrence of immune-related adverse events(irAEs).The predictive potential of ne... We conducted a comprehensive review of existing prediction models pertaining to the efficacy of immune-checkpoint inhibitor(ICI)and the occurrence of immune-related adverse events(irAEs).The predictive potential of neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)in determining ICI effectiveness has been extensively investigated,while limited research has been conducted on predicting irAEs.Furthermore,the combined model incor-porating NLR and PLR,either with each other or in conjunction with additional markers such as carcinoembryonic antigen,exhibits superior predictive capabilities compared to individual markers alone.NLR and PLR are promising markers for clinical applications.Forthcoming models ought to incorporate established efficacious models and newly identified ones,thereby constituting a multifactor composite model.Furthermore,efforts should be made to explore effective clinical application approaches that enhance the predictive accuracy and efficiency. 展开更多
关键词 Neutrophil-to-lymphocyte ratio Platelet-to-lymphocyte ratio Immunecheckpoint inhibitor Immune-related adverse event
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Clinical study of neutrophil-to-lymphocyte ratio and platelet-tolymphocyte ratio in hypertriglyceridemia-induced acute pancreatitis and acute biliary pancreatitis with persistent organ failure
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作者 Mu-Sen Xu Jia-Le Xu +5 位作者 Xin Gao Shao-Jian Mo Jia-Yu Xing Jia-Hang Liu Yan-Zhang Tian Xi-Feng Fu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1647-1659,共13页
BACKGROUND The neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)are novel inflammatory indicators that can be used to predict the severity and prognosis of various diseases.We categorize acute p... BACKGROUND The neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)are novel inflammatory indicators that can be used to predict the severity and prognosis of various diseases.We categorize acute pancreatitis by etiology into acute biliary pancreatitis(ABP)and hypertriglyceridemia-induced acute pancreatitis(HTGP).AIM To investigate the clinical significance of NLR and PLR in assessing persistent organ failure(POF)in HTGP and ABP.METHODS A total of 1450 patients diagnosed with acute pancreatitis(AP)for the first time at Shanxi Bethune Hospital between January 2012 and January 2023 were enrolled.The patients were categorized into two groups according to the etiology of AP:ABP in 530 patients and HTGP in 241 patients.We collected and compared the clinical data of the patients,including NLR,PLR,and AP prognostic scoring systems,within 48 h of hospital admission.RESULTS The NLR(9.1 vs 6.9,P<0.001)and PLR(203.1 vs 160.5,P<0.001)were significantly higher in the ABP group than in the HTGP group.In the HTGP group,both NLR and PLR were significantly increased in patients with severe AP and those with a SOFA score≥3.Likewise,in the ABP group,NLR and PLR were significantly elevated in patients with severe AP,modified computed tomography severity index score≥4,Japanese Severity Score≥3,and modified Marshall score≥2.Moreover,NLR and PLR showed predictive value for the development of POF in both the ABP and HTGP groups.CONCLUSION NLR and PLR vary between ABP and HTGP,are strongly associated with AP prognostic scoring systems,and have predictive potential for the occurrence of POF in both ABP and HTGP. 展开更多
关键词 Acute pancreatitis GALLSTONE HYPERTRIGLYCERIDEMIA Neutrophil-to-lymphocyte ratio Platelet-to-lymphocyte ratio Persistent organ failure
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Effect of length-width ratio of rounded rectangle aquaculture tank in dual-diagonal-inlet layout on hydrodynamics
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作者 Meng LI Xiaozhong REN +4 位作者 Shupeng DU Wei SUN Chenxu ZHAO Hangfei LIU Xianying SHI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第5期1695-1709,共15页
To adapt to the change of aquaculture workshop site,optimize the shape of aquaculture tanks and improve the utilization rate of breeding space,it is necessary to determine the appropriate length width ratio parameters... To adapt to the change of aquaculture workshop site,optimize the shape of aquaculture tanks and improve the utilization rate of breeding space,it is necessary to determine the appropriate length width ratio parameters of aquaculture tanks.In this paper,computational fluid dynamics(CFD)technology is adopted to study the flow field performance of aquaculture tanks with different L/B ratios(L:the length;B:the width,of aquaculture tank)and different jet direction conditions(lengthways jet and widthways jet).A three-dimensional numerical calculation model of turbulence in rounded rectangle aquaculture tanks in dual-diagonal-inlet layout was established.Jet directions are arranged lengthways and widthways,and the water flow velocity,resistance coefficient change,vorticity,etc.are analyzed under two working conditions.Results show that the flow field performance in aquaculture tank decreases with the increase of the L/B ratio.The flow field performed well when L/B was 1.0-1.3,sharply dropped at 1.4-1.6,and poor at 1.7-1.9.The results provided a theoretical basis for the design and optimization in flow field performance of the industrialized circulating aquaculture tanks. 展开更多
关键词 aquaculture tank length-width ratio computational fluid dynamic hydrodynamic
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Experimental Study of Local Scour Around Four Piles Under Different Attack Angles and Gap Ratios
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作者 LIU Ming-ming TANG Guo-qiang +1 位作者 JIN Xin GENG Shao-yang 《China Ocean Engineering》 SCIE EI CSCD 2024年第4期612-624,共13页
In an effort to investigate and quantify the patterns of local scour,researchers embarked on an in-depth study using a systematic experimental approach.The research focused on the effects of local scour around a set o... In an effort to investigate and quantify the patterns of local scour,researchers embarked on an in-depth study using a systematic experimental approach.The research focused on the effects of local scour around a set of four piles,each subjected to different hydromechanical conditions.In particular,this study aimed to determine how different attack angles—the angles at which the water flow impinges on the piles,and gap ratios—the ratios of the spacing between the piles to their diameters,influence the extent and nature of scour.A comprehensive series of 35 carefully designed experiments were orchestrated,each designed to dissect the nuances in how the gap ratio and attack angle might contribute to changes in the local scour observed at the base of pile groups.During these experimental trials,a wealth of local scour data were collected to support the analysis.These data included precise topographic profiles of the sediment bed around the pile groups,as well as detailed scour time histories showing the evolution of scour at strategic feature points throughout the test procedure.The analysis of the experimental data provided interesting insights.The study revealed that the interplay between the gap ratio and the attack angle had a pronounced influence on the scouring dynamics of the pile groups.One of the key observations was that the initial phases of scour,particularly within the first hour of water flow exposure,were characterized by a sharp increase in the scour depth occurring immediately in front of the piles.After this initial rapid development,the scour depth transitioned to a more gradual change rate.In contrast,the scour topography around the piles continuously evolved.This suggests that sediment displacement and the associated sculpting of the seabed around pile foundations are sustained and progressive processes,altering the underwater landscape over time.The results of this empirical investigation have significant implications for the design and construction of offshore multi-pile foundations,providing a critical reference for engineers and designers to estimate the expected scour depth around such structures,which is an integral part of decisions regarding foundation design,selection of structural materials,and implementation of scour protection measures. 展开更多
关键词 local scour PILES gap ratio attack angle
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Effects of the Water-Cement Ratio and the Molding Temperature on the Hydration Heat of Cement
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作者 代金鹏 HE Jie +1 位作者 WANG Qicai LOU Xuyu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期990-998,共9页
The effects of the water-cement ratio and the molding temperature on the hydration heat of cement were investigated with semi-adiabatic calorimetry.The specimens were prepared with water-cement ratios of 0.31,0.38,and... The effects of the water-cement ratio and the molding temperature on the hydration heat of cement were investigated with semi-adiabatic calorimetry.The specimens were prepared with water-cement ratios of 0.31,0.38,and 0.45,and the molding temperature was specified at 10 and 20℃.The experimental results show that,as the water-binder ratio increases,the value of the second temperature peak on the temperature curve of the cement paste decreases,and the age at which the peak appears is delayed.The higher the water-cement ratio,the higher the hydration heat release in the early period of cement hydration,but this trend reverses in the late period.There are intersection points of the total hydration heat curve of the cement pastes under the influence of the water-cement ratio,and this law can be observed at both molding temperatures.With the increase in the molding temperature,the age of the second temperature peak on the temperature curve of the cement paste will advance,but the temperature peak will decrease.The higher the molding temperature,the earlier the acceleration period of the cement hydration began,and the larger the hydration heat of the cement in the early stage,but the smaller the total heat in the late period.A subsection function calculation model of the hydration heat,which was based on the existing models,was proposed in order to predict the heat of the hydration of the concrete. 展开更多
关键词 semi-adiabatic calorimetry hydration heat water-cement ratio molding temperature MODELING
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Prognostic role of platelet-to-lymphocyte ratio and neutrophil-to-lymphocyte ratio in patients with non-metastatic and metastatic prostate cancer:A meta-analysis and systematic review
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作者 Stefano Salciccia Marco Frisenda +11 位作者 Giulio Bevilacqua Pietro Viscuso Paolo Casale Ettore De Berardinis Giovanni Battista Di Pierro Susanna Cattarino Gloria Giorgino Davide Rosati Francesco Del Giudice Alessandro Sciarra Gianna Mariotti Alessandro Gentilucci 《Asian Journal of Urology》 CSCD 2024年第2期191-207,共17页
Objective: To analyze data available in the literature regarding a possible prognostic value of the platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) in prostate cancer (PCa) patients stratif... Objective: To analyze data available in the literature regarding a possible prognostic value of the platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) in prostate cancer (PCa) patients stratified in non-metastatic and metastatic diseases.Methods: A literature search process was performed following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. In our meta-analysis, the pooled event rate estimated and the pooled hazard ratio were calculated using a random effect model.Results: Forty-two articles were selected for our analysis. The pooled risk difference for non-organ confined PCa between high and low NLR cases was 0.06 (95% confidence interval [CI]: −0.03-0.15) and between high and low PLR cases increased to 0.30 (95% CI: 0.16-0.43). In non-metastatic PCa cases, the pooled hazard ratio for overall mortality between high and low NLR was 1.33 (95% CI: 0.78-1.88) and between high and low PLR was 1.47 (95% CI: 0.91-2.03), whereas in metastatic PCa cases, between high and low NLR was 1.79 (95% CI: 1.44-2.13) and between high and low PLR was 1.05 (95% CI: 0.87-1.24).Conclusion: The prognostic values of NLR and PLR in terms of PCa characteristics and responses after treatment show a high level of heterogeneity of results among studies. These two ratios can represent the inflammatory and immunity status of the patient related to several conditions. A higher predictive value is related to a high NLR in terms of risk for overall mortality in metastatic PCa cases under systemic treatments. 展开更多
关键词 Prostatic neoplasm Neutrophil-to-lymphocyte ratio Platelet-to-lymphocyteratio META-ANALYSIS Radical prostatectomy METASTATIC
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Optimal scheduling of a township integrated-energy system using the adjustable heat-electricity ratio model
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作者 Quan Chen Jingyi Wang +4 位作者 Min Cang Xiaomeng Zhai Xi Cheng Shuang Wu Dongwei Li 《Global Energy Interconnection》 EI CSCD 2024年第1期48-60,共13页
With the expansion and implementation of rural revitalization strategies,there is a constant need for new energy sources for the construction of new townships.Consequently,integrated energy systems with the interconne... With the expansion and implementation of rural revitalization strategies,there is a constant need for new energy sources for the construction of new townships.Consequently,integrated energy systems with the interconnection and interaction of multiple energy sources are developing rapidly.Biomass energy,a renewable green energy source with low pollution and wide distribution,has significant application potential in integrated energy systems.Considering the application of biomass energy in townships,this study established an integrated biomass energy system and proposed a model to optimize its operation.Lowest economic cost and highest clean energy utilization rate were considered as the objective functions.In addition,a plan was suggested to adjust the heat-electricity ratio based on the characteristics of the combined heat and power of the biomass.Finally,a simulation analysis conducted for a town in China was discussed,demonstrating that the construction of a township integrated-energy system and the use of biomass can significantly reduce operating costs and improve the energy utilization rate.Moreover,by adjusting the heat-electricity ratio,the economic cost was further reduced by 6.70%,whereas the clean energy utilization rate was increased by 5.14%. 展开更多
关键词 Biomass energy Integrated-energy system Afterburning device Heat-electricity ratio Operation optimization
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Isotopic dependence of the yield ratios of light fragments from different projectiles and their unified neutron skin thicknesses
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作者 Ting-Zhi Yan Shan Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期228-236,共9页
The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(ever... The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(every third isotopes)+112 Sn for full reduced impact parameters using the isospin-dependent quantum molecular dynamics(IQMD)model.The neutron and proton density distributions and root-mean-square radii of the reaction systems were obtained using the Skyrme-Hartree-Fock model,which was used for the phase space initialization of the projectile and target in IQMD.We defined the unified neutron skin thickness asΔRnp=<r^(2)>^(1∕2) n−<r^(2)>^(1∕2)p,which was negative for neutron-deficient nuclei.The unifiedΔRnp values for nuclei with the same relative neutron excess from different isotopic chains were nearly equal,except for extreme neutron-rich isotopes,which is a type of scaling behavior.The yield ratios of the three isotopic chain-induced reactions,which depended on the reduced impact parameter and unified neutron skin thickness,were studied.The results showed that both R(n/p)and R(^(3)H∕^(3)He)decreased with a reduced impact parameter for extreme neutron-deficient isotopes;however,they increased with reduced impact parameters for extreme neutron-rich isotopes,and increased with theΔRnp of the projectiles for all reduced impact parameters.In addition,a scaling phenomenon was observed betweenΔR np and the yield ratios in peripheral colli-sions from different isotopic chain projectiles(except for extreme neutron-rich isotopes).Thus,R(n/p)and R(^(3)H∕^(3)He)from peripheral collisions were suggested as experimental probes for extracting the neutron or proton skin thicknesses of non-extreme neutron-rich nuclei from different isotopic chains. 展开更多
关键词 Exotic nuclei Unified neutron skin thickness Yield ratios IQMD
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Carbonation of Pure Minerals in Portland Cement:Evolution in Products as a Function of Water-to-solid Ratio
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作者 XIONG Kun SHANG Xiaopeng +1 位作者 LI Hongyan WANG Dan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1214-1222,共9页
Minerals in Portland cement including tricalcium silicate(C_(3)S),β-dicalcium silicate(β-C_(2)S),tricalcium aluminate(C_(3)A),and tetracalcium ferroaluminate(C_(4)AF),show a significantly different activity and prod... Minerals in Portland cement including tricalcium silicate(C_(3)S),β-dicalcium silicate(β-C_(2)S),tricalcium aluminate(C_(3)A),and tetracalcium ferroaluminate(C_(4)AF),show a significantly different activity and product evolution for CO_(2)curing at various water-to-solid ratios.These pure minerals were synthesized and subject to CO_(2)curing in this study to make an in-depth understanding for the carbonation properties of cement-based materials.Results showed that the optimum water-to-solid ratios of C_(3)S,β-C_(2)S,C_(3)A and C_(4)AF were 0.25,0.15,0.30 and 0.40 for carbonation,corresponding to 2 h carbonation degree of 38.5%,38.5%,24.2%,and 21.9%,respectively.The produced calcite duringβ-C_(2)S carbonation decreased as the water-to-solid ratio increased,with an increase in content of metastable CaCO_(3)of vaterite and aragonite.The thermodynamic stability of CaCO_(3)produced during carbonation was C_(3)A>C_(4)AF>β-C_(2)S>C_(3)S.The carbonation degree of Portland cement was predicted based on the results of pure minerals and the composition of cement,and the error of predicted production of CaCO_(3)was only 1.1%,which provides a potential method to predict carbonation properties of systems with a complex mineral composition. 展开更多
关键词 accelerated carbonation portland cement calcium carbonate water-to-solid ratio
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Combining systemic inflammatory response index and albumin fibrinogen ratio to predict early serious complications and prognosis after resectable gastric cancer
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作者 Jing-Yao Ren Da Wang +3 位作者 Li-Hui Zhu Shuo Liu Miao Yu Hui Cai 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期732-749,共18页
BACKGROUND Gastric cancer has a high incidence and fatality rate,and surgery is the preferred course of treatment.Nonetheless,patient survival rates are still low,and the incidence of major postoperative complications... BACKGROUND Gastric cancer has a high incidence and fatality rate,and surgery is the preferred course of treatment.Nonetheless,patient survival rates are still low,and the incidence of major postoperative complications cannot be disregarded.The systemic inflammatory response,nutritional level,and coagulation status are key factors affecting the postoperative recovery and prognosis of gastric cancer patients.The systemic inflammatory response index(SIRI)and the albumin fibrinogen ratio(AFR)are two valuable comprehensive indicators of the severity and prognosis of systemic inflammation in various medical conditions.AIM To assess the clinical importance and prognostic significance of the SIRI scores and the AFR on early postoperative outcomes in patients undergoing radical gastric cancer surgery.METHODS We conducted a retrospective analysis of the clinicopathological characteristics and relevant laboratory indices of 568 gastric cancer patients from January 2018 to December 2019.We calculated and compared two indicators of inflammation and then examined the diagnostic ability of combined SIRI and AFR values for serious early postoperative complications.We scored the patients and categorized them into three groups based on their SIRI and AFR levels.COX analysis was used to compare the three groups of patients the prognostic value of various preoperative SIRI-AFR scores for 5-year overall survival(OS)and disease-free survival(DFS).RESULTS SIRI-AFR scores were an independent risk factor for prognosis[OS:P=0.004;hazards ratio(HR)=3.134;DFS:P<0.001;HR=3.543]and had the highest diagnostic power(area under the curve:0.779;95%confidence interval:0.737-0.820)for early serious complications in patients with gastric cancer.The tumor-node-metastasis stage(P=0.001),perioperative transfusion(P=0.044),positive carcinoembryonic antigen(P=0.014)findings,and major postoperative complications(P=0.011)were factors associated with prognosis.CONCLUSION Preoperative SIRI and AFR values were significantly associated with early postoperative survival and the occurrence of severe complications in gastric cancer patients. 展开更多
关键词 Inflammation Albumin fibrinogen ratio Gastric cancer COMPLICATIONS PROGNOSIS
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Monocyte to High-density Lipoprotein Cholesterol Ratio as a Predictor of Nonalcoholic Fatty Liver Disease in Childhood Obesity
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作者 Jun-feng ZHANG Feng-qing CAI +1 位作者 Xiu-cai ZHANG Qing YE 《Current Medical Science》 SCIE CAS 2024年第4期692-697,共6页
Objective Inflammation is involved in the development and progression of nonalcoholic fatty liver disease(NAFLD).The monocyte to high-density lipoprotein cholesterol ratio(MHR)has emerged as a marker for various infla... Objective Inflammation is involved in the development and progression of nonalcoholic fatty liver disease(NAFLD).The monocyte to high-density lipoprotein cholesterol ratio(MHR)has emerged as a marker for various inflammation-related diseases.The aim of the present study was to investigate the association between the MHR and NAFLD in a population with childhood obesity.Methods Based on hepatic ultrasound,a total of 504 children with obesity(357 with NAFLD and 147 without NAFLD)were included in the study.The correlation between the MHR and NAFLD risk factors was assessed by Pearson’s and Spearman’s analyses.Multivariate stepwise logistic regression analyses were conducted to explore the association between the MHR and the risk of NAFLD.Results The MHR in patients with NAFLD was significantly greater than that in patients without NAFLD[0.52(0.44-0.67)versus 0.44(0.34-0.57),P<0.001].Multivariate stepwise logistic regression analysis demonstrated that the MHR[odds ratio(OR):1.033,95%confidence interval(CI):1.015-1.051;P<0.001]was an independent predictor of NAFLD in childhood obesity patients,as were age(OR:1.205,95%CI:1.059-1.371;P=0.005],waist circumference[OR:1.037,95%CI:1.008-1.067;P=0.012],and alanine transaminase[OR:1.067,95%CI:1.045-1.089;P<0.001].Additionally,MHR quartiles showed a significant positive association with the incidence of NAFLD after adjusting for potential confounding factors.Conclusion The present study showed that the MHR may serve as an available and useful indicator of NAFLD in individuals with childhood obesity. 展开更多
关键词 nonalcoholic fatty liver disease OBESITY monocyte-to-high-density lipoprotein ratio MARKER
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