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Cost-Effective Monitoring of the Fuel Air Equivalence-Ratio with a Lambda Sensor and a Microcontroller in a Downdraft Biomass Gasifier
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作者 Jean Fidele Nzihou Salou Hamidou +2 位作者 Ousmane Zoundi Frederic Ouattara Bila Gerard Segda 《Open Journal of Applied Sciences》 2024年第2期545-560,共16页
The operation of biomass treatment devices such as gasifiers is based on the control of key parameters that play an important role in product formation. These include: temperature, excess oxygen, relative humidity and... The operation of biomass treatment devices such as gasifiers is based on the control of key parameters that play an important role in product formation. These include: temperature, excess oxygen, relative humidity and biomass composition. This work focuses on excess oxygen and temperature. Unfortunately, flue gas oxygen analyzers are expensive and not accessible to small industries. However, the equivalence ratio is linked to excess oxygen and has the advantage of not depending on biomass composition. This study therefore focuses on the design and development of a device for controlling this equivalence ratio by measuring oxygen concentration using a self-propelled Lambda probe, and a system for monitoring this equivalence ratio using an Arduino Uno 3 microcontroller. The temperature is recorded with an accuracy of ±1.5°C. For a heating time of 10 minutes, the response time to temperature change is around 3 seconds, which is sufficient for the device to function properly. This simple device is an efficient and cost-effective means of checking the equivalence ratio. 展开更多
关键词 Equivalence ratio Biomass GASIFICATION Lambda Sensor MICROCONTROLLER C++
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Cost-effectiveness of robotic-assisted spinal surgery:A single-center retrospective study
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作者 Sorayouth Chumnanvej Krish Ariyaprakai +3 位作者 Branesh M.Pillai Jackrit Suthakorn Sharvesh Gurusamy Siriluk Chumnanvej 《Laparoscopic, Endoscopic and Robotic Surgery》 2023年第4期147-153,共7页
Objective:Robotic-assisted spine surgeries(RASS)have been shown to enhance precision,reduce operative time,prevent complications,facilitate minimally invasive spinal surgery,and decrease revision surgery rates,leading... Objective:Robotic-assisted spine surgeries(RASS)have been shown to enhance precision,reduce operative time,prevent complications,facilitate minimally invasive spinal surgery,and decrease revision surgery rates,leading to improved patient outco mes This study aimed to compare the cost-effectiveness of RAs's and non-robotic-assisted surgery for degenerative spine disease at a single center.Me thods:This retrospective study,including 122 patients,was conducted at a single center from March 2015 to February 2022.Patients who underwent ro bot-assisted surgery were assigned to the robotgroup,and patients who underwent non-robotic-assisted surgery were assigned to the non-mmbot group.Various data,indluding demographic information,surgical details,outcomes,and cost-effectiveness,were colected for both groups.The cost-effectiveness was determined using the incremental cost-effectiveness ratio(ICER),and subgroup analysis was conducted for patients with 1 or 2 levels of spi-nal instrumentation.The analysis was performed using STATA SE version 15 and Tree.Age Pro 2020,with Monte Caro simulations for the cost-effectiveness acceptability curve.Results The owerallICER was$22,572,but it decreased to$16,980 when considering cases with only 1or 2 levels of instrumentation.RASS is deemed cost-effective when the willi ingness to pay is$3000-$4000 if less than 2 levels of the spine are instrumented.Conchsions:The cost-effectiveness of robot icassistance be comes apparent whenthere isa reduced need for open surgeries,leading to decreased d revision rates caused by complications such as misplaced screwsor infctions.Therefore,it is advisable to allocate healthcare budget resou Irces to spine robots,as RASS PIDves to be cost-effective,partic cularly when only two or Ewer spinal levels require instrumentation. 展开更多
关键词 ROBOTIC Spine surgery Incremental cost-effectiveness ratio cost-effectiveness acceptability curve Levels of spine fixation
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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》 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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Cost-Effectiveness Analysis of Combined Chemotherapy Regimen Containing Bedaquiline in the Treatment of Multidrug-Resistant Tuberculosis in China
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作者 XU Cai Hong QIU Ying Peng +5 位作者 HE Zi Long HU Dong Mei YUE Xiao CHEN Zhong Dan XU Yuan Yuan ZHAO Yan Lin 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第6期501-509,共9页
Objective This study aims to estimate the cost-effectiveness of the combined chemotherapy regimen containing Bedaquiline(BR)and the conventional treatment regimen(CR,not containing Bedaquiline)for the treatment of adu... Objective This study aims to estimate the cost-effectiveness of the combined chemotherapy regimen containing Bedaquiline(BR)and the conventional treatment regimen(CR,not containing Bedaquiline)for the treatment of adults with multidrug-resistant tuberculosis(MDR-TB)in China.Methods A combination of a decision tree and a Markov model was developed to estimate the cost and effects of MDR patients in BR and CR within ten years.The model parameter data were synthesized from the literature,the national TB surveillance information system,and consultation with experts.The incremental cost-effectiveness ratio(ICER)of BR vs.CR was determined.Results BR(vs.CR)had a higher sputum culture conversion rate and cure rate and prevented many premature deaths(decreased by 12.8%),thereby obtaining more quality-adjusted life years(QALYs)(increased by 2.31 years).The per capita cost in BR was as high as 138,000 yuan,roughly double that of CR.The ICER for BR was 33,700 yuan/QALY,which was lower than China's 1×per capita Gross Domestic Product(GDP)in 2020(72,400 yuan).Conclusion BR is shown to be cost effective.When the unit price of Bedaquiline reaches or falls below57.21 yuan per unit,BR is expected to be the dominant strategy in China over CR. 展开更多
关键词 Bedaquiline cost-effectiveness Multidrug-resistant tuberculosis China
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Cost-effectiveness of patient specific vs conventional instrumentation for total knee arthroplasty:A systematic review and meta-analysis
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作者 Isobel M Dorling Lars Geenen +3 位作者 Marion J L F Heymans Jasper Most Bert Boonen Martijn G M Schotanus 《World Journal of Orthopedics》 2023年第6期458-470,共13页
BACKGROUND Over the past years,patient specific instrumentation(PSI)for total knee arthroplasty(TKA)has been implemented and routinely used.No clear answer has been given on its associated cost and cost-effectiveness ... BACKGROUND Over the past years,patient specific instrumentation(PSI)for total knee arthroplasty(TKA)has been implemented and routinely used.No clear answer has been given on its associated cost and cost-effectiveness when compared to conventional instrumentation(CI)for TKA.AIM To compare the cost and cost-effectiveness of PSI TKA compared to CI TKA.METHODS A literature search was performed in healthcare,economical healthcare,and medical databases(MEDLINE,EMBASE,CINAHL,Web of Science,Cochrane Library,EconLit).It was conducted in April 2021 and again in January 2022.Relevant literature included randomised controlled trials,retrospective studies,prospective studies,observational studies,and case control studies.All studies were assessed on methodological quality.Relevant outcomes included incremental cost-effectiveness ratio,quality-adjusted life years,total costs,imaging costs,production costs,sterilization associated costs,surgery duration costs and readmission rate costs.All eligible studies were assessed for risk of bias.Meta-analysis was performed for outcomes with sufficient data.RESULTS Thirty-two studies were included into the systematic review.Two were included in the metaanalysis.3994 PSI TKAs and 13267 CI TKAs were included in the sample size.The methodological quality of the included studies,based on Consensus on Health Economic Criteria-scores and risk of bias,ranged from average to good.PSI TKA costs less than CI TKA when considering mean operating room time and its associated costs and tray sterilization per patient case.PSI TKA costs more compared to CI TKA when considering imaging and production costs.Considering total costs per patient case,PSI TKA is more expensive in comparison to CI TKA.Meta-analysis comparing total costs for PSI TKA,and CI TKA showed a significant higher cost for PSI TKA.CONCLUSION Cost for PSI and CI TKA can differ when considering distinct aspects of their implementation.Total costs per patient case are increased for PSI TKA when compared to CI TKA. 展开更多
关键词 Total knee arthroplasty Patient specific instrumentation Instrumentation for total knee arthroplasty cost-effectiveness Systematic review
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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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Cost-effectiveness Analysis of Insulin Degludec and Liraglutide Injection in the Treatment of Type 2 Diabetes
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作者 Sun Quan Zhang Fang Dong Li 《Asian Journal of Social Pharmacy》 2023年第3期281-295,共15页
Objective To analyze the cost-effectiveness of insulin degludec and liraglutide injection(IDegLira)compared with insulin glargine plus insulin aspart(IGar plus IAsp)in the treatment of type 2 diabetes mellitus(T2DM)ba... Objective To analyze the cost-effectiveness of insulin degludec and liraglutide injection(IDegLira)compared with insulin glargine plus insulin aspart(IGar plus IAsp)in the treatment of type 2 diabetes mellitus(T2DM)based on the price of IDegLira before and after it was successfully admitted to the National Reimbursable Drug List(NRDL).Methods Cost and effectiveness parameters were obtained through systematic retrieval from PubMed,ScienceDirect,CNKI,and Wanfang database.A cost-effectiveness analysis(CEA)model was established to analyze the economics using IDegLira for T2DM patients with 1 to 5 years of medication.Results and Conclusion Before IDegLira was admitted to NRDL,its economic advantages over the IGlar plus Iasp regimen became more significant as patients’medication time prolonged.After being admitted to NRDL,with 1 year of medication,the medical cost of IDegLira decreased by 2853.91 yuan and the quality adjusted life years(QALY)increased by 0.12055 than IGar plus IAsp.The sensitivity analysis was highly consistent with the results of the baseline result.After being admitted to NRDL,for patients with T2DM who have poor blood glucose control,IDegLira is absolutely an economic advantage scheme compared with IGar plus IAsp. 展开更多
关键词 insulin degludec and liraglutide injection insulin glargine insulin aspart cost-effectiveness analysis
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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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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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Added value of ratio of cross diameters of the appendix in ultrasound diagnosis of acute appendicitis
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作者 Feng-Wa Gu Si-Ze Wu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期21-28,共8页
BACKGROUND The maximum outer diameter(MOD)of the appendix is an essential parameter for diagnosing acute appendicitis,but there is space for improvement in ultrasound(US)diagnostic performance.AIM To investigate wheth... BACKGROUND The maximum outer diameter(MOD)of the appendix is an essential parameter for diagnosing acute appendicitis,but there is space for improvement in ultrasound(US)diagnostic performance.AIM To investigate whether combining the ratio of the cross diameters(RATIO)of the appendix with MOD of the appendix can enhance the diagnostic performance of acute appendicitis.METHODS A retrospective study was conducted,and medical records of 233 patients with acute appendicitis and 112 patients with a normal appendix were reviewed.The MOD and RATIO of the appendix were calculated and tested for their diagnostic performance of acute appendicitis,both individually and in combination.RESULTS The RATIO for a normal appendix was 1.32±0.16,while for acute appendicitis it was 1.09±0.07.The cut-off value for RATIO was determined to be≤1.18.The area under the receiver operating characteristic curve(AUC)for diagnosing acute appendicitis using RATIO≤1.18 and MOD>6 mm was 0.870 and 0.652,respectively.There was a significant difference in AUC between RATIO≤1.18 and MOD>6 mm(P<0.0001).When comparing the combination of RATIO≤1.18 and MOD>6 mm with MOD>6 mm alone,the combination showed increased specificity,positive predictive value(PPV),and AUC.However,the sensitivity and negative predictive value decreased.CONCLUSION Combining RATIO of the appendix≤1.18 and MOD>6 mm can significantly improve the specificity,PPV,and AUC in the US diagnosis of acute appendicitis. 展开更多
关键词 Acute appendicitis DIAMETER ratio Diagnosis ULTRASOUND
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Influence of Trailing-Edge Wear on the Vibrational Behavior of Wind Turbine Blades
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作者 Yuanjun Dai Xin Wei +2 位作者 Baohua Li Cong Wang Kunju Shi 《Fluid Dynamics & Materials Processing》 EI 2024年第2期337-348,共12页
To study the impact of the trailing-edge wear on the vibrational behavior of wind-turbine blades,unworn blades and trailing-edge worn blades have been assessed through relevant modal tests.According to these experimen... To study the impact of the trailing-edge wear on the vibrational behavior of wind-turbine blades,unworn blades and trailing-edge worn blades have been assessed through relevant modal tests.According to these experiments,the natural frequencies of trailing-edge worn blades-1,-2,and-3 increase the most in the second to fourth order,thefifth order increases in the middle,and thefirst order increases the least.The damping ratio data indi-cate that,in general,thefirstfive-order damping ratios of trailing-edge worn blades-1 and trailing-edge worn blades-2 are reduced,and thefirstfive-order damping ratios of trailing-edge worn blades-3 are slightly improved.The mode shape diagram shows that the trailing-edge worn blades-1 and-2 have a large swing in the tip and the blade,whereas the second-and third-order vibration shapes of the trailing edge-worn blade-3 tend to be improved.Overall,all these results reveal that the blade’s mass and the wear area are the main fac-tors affecting the vibration characteristics of wind turbine blades. 展开更多
关键词 Wind turbine modal test natural frequency damping ratio mode shape
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Elliptical vibration chiseling:a novel process for texturing ultra-high-aspect-ratio microstructures on the metallic surface
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作者 Zhiwei Li Jianfu Zhang +3 位作者 Zhongpeng Zheng Pingfa Feng Dingwen Yu Jianjian Wang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期449-467,共19页
High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon devices.However,the fast and cost-effect... High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon devices.However,the fast and cost-effective fabrication of high-aspect-ratio microstructures on metallic surfaces remains challenging for existing techniques.This study proposes a novel cutting-based process,namely elliptical vibration chiseling(EV-chiseling),for the high-efficiency texturing of surface microstructures with an ultrahigh aspect ratio.Unlike conventional cutting,EV-chiseling superimposes a microscale EV on a backward-moving tool.The tool chisels into the material in each vibration cycle to generate an upright chip with a high aspect ratio through material deformation.Thanks to the tool’s backward movement,the chip is left on the material surface to form a microstructure rather than falling off.Since one microstructure is generated in one vibration cycle,the process can be highly efficient using ultrafast(>1 kHz)tool vibration.A finite element analysis model is established to explore the process mechanics of EV-chiseling.Next,a mechanistic model of the microstructured surface generation is developed to describe the microstructures’aspect ratio dependency on the process parameters.Then,surface texturing tests are performed on copper to verify the efficacy of EV-chiseling.Uniformed micro ribs with a spacing of 1–10μm and an aspect ratio of 2–5 have been successfully textured on copper.Compared with the conventional EV-cutting that uses a forward-moving tool,EV-chiseling can improve the aspect ratio of textured microstructure by up to 40 times.The experimental results also verify the accuracy of the developed surface generation model of microstructures.Finally,the effects of elliptical trajectory,depth of cut,tool shape,and tool edge radius on the surface generation of micro ribs have been discussed. 展开更多
关键词 metallic microstructure high aspect ratio backward-moving cutting vibration cutting chiseling material deformation
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Topology Optimization of Metamaterial Microstructures for Negative Poisson’s Ratio under Large Deformation Using a Gradient-Free Method
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作者 Weida Wu Yiqiang Wang +1 位作者 Zhonghao Gao Pai Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2001-2026,共26页
Negative Poisson’s ratio(NPR)metamaterials are attractive for their unique mechanical behaviors and potential applications in deformation control and energy absorption.However,when subjected to significant stretching... Negative Poisson’s ratio(NPR)metamaterials are attractive for their unique mechanical behaviors and potential applications in deformation control and energy absorption.However,when subjected to significant stretching,NPR metamaterials designed under small strain assumption may experience a rapid degradation in NPR performance.To address this issue,this study aims to design metamaterials maintaining a targeted NPR under large deformation by taking advantage of the geometry nonlinearity mechanism.A representative periodic unit cell is modeled considering geometry nonlinearity,and its topology is designed using a gradient-free method.The unit cell microstructural topologies are described with the material-field series-expansion(MFSE)method.The MFSE method assumes spatial correlation of the material distribution,which greatly reduces the number of required design variables.To conveniently design metamaterials with desired NPR under large deformation,we propose a two-stage gradient-free metamaterial topology optimization method,which fully takes advantage of the dimension reduction benefits of the MFSE method and the Kriging surrogate model technique.Initially,we use homogenization to find a preliminary NPR design under a small deformation assumption.In the second stage,we begin with this preliminary design and minimize deviations in NPR from a targeted value under large deformation.Using this strategy and solution technique,we successfully obtain a group of NPR metamaterials that can sustain different desired NPRs in the range of[−0.8,−0.1]under uniaxial stretching up to 20% strain.Furthermore,typical microstructure designs are fabricated and tested through experiments.The experimental results show good consistency with our numerical results,demonstrating the effectiveness of the present gradientfree NPR metamaterial design strategy. 展开更多
关键词 Topology optimization microstructural design negative Poisson’s ratio large deformation
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Predictive Value of the Neutrophil to Lymphocyte Ratio (NLR) to Predict the Development of Preeclampsia and Pregnancy Induced Hypertension at 1st Trimester
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作者 Pradeepa Sanjeewa 《Open Journal of Obstetrics and Gynecology》 2024年第4期547-559,共13页
Introduction: Hypertensive disorder in pregnancy affects 4 to 6 percent of all pregnancies and carries risks for the both baby and the mother. Only a few groups of women who are at high-risk pregnancies are received p... Introduction: Hypertensive disorder in pregnancy affects 4 to 6 percent of all pregnancies and carries risks for the both baby and the mother. Only a few groups of women who are at high-risk pregnancies are received prophylaxis Aspirin, more than 15 percent of women develop pre-eclampsia with a single minor risk factor. Methods: This descriptive cross-sectional study was conducted to compare the 1<sup>st</sup> trimester NLR value of normotensive, pregnancy induced hypertensive and pre-eclamptic pregnant women. The study was conducted with a sample of 416, antenatal patients who were admitted to ward 25, at Colombo North Teaching Hospital Ragama. Data was collected as separated three groups. NLR value was calculated separately and ANOVA test was used to analyze the 3 categorical data. Post HOC test was done to assess the multiple comparison. Results: The prevalence rates of pregnancy induced hypertension and pre-eclampsia among the pregnant women were 8.6% and 5.7%. The mean NLR values of normotensive group was 2.708, pregnancy induced hypertensive group was 2.650 and pre eclamptic group was 3.789. There was a significant difference in NLR value between pre eclamptic group and other two groups with P value of Conclusion: The 1<sup>st</sup> trimester NLR value of pre eclamptic patients significantly increased compared to normotensive women. 展开更多
关键词 PRE-ECLAMPSIA Neutrophil to Lymphocyte ratio 1st Trimester
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Predictive value of positive lymph node ratio in patients with locally advanced gastric remnant cancer
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作者 Meng Zhuo Lei Tian +3 位作者 Ting Han Teng-Fei Liu Xiao-Lin Lin Xiu-Ying Xiao 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期833-843,共11页
BACKGROUND Traditional lymph node stage(N stage)has limitations in advanced gastric remnant cancer(GRC)patients;therefore,establishing a new predictive stage is necessary.AIM To explore the predictive value of positiv... BACKGROUND Traditional lymph node stage(N stage)has limitations in advanced gastric remnant cancer(GRC)patients;therefore,establishing a new predictive stage is necessary.AIM To explore the predictive value of positive lymph node ratio(LNR)according to clinicopathological characteristics and prognosis of locally advanced GRC.METHODS Seventy-four patients who underwent radical gastrectomy and lymphadenectomy for locally advanced GRC were retrospectively reviewed.The relationship between LNR and clinicopathological characteristics was analyzed.The survival analysis was performed using Kaplan-Meier survival curves and Cox regression model.RESULTS Number of metastatic LNs,tumor diameter,depth of tumor invasion,Borrmann type,serum tumor biomarkers,and tumor-node-metastasis(TNM)stage were correlated with LNR stage and N stage.Univariate analysis revealed that the factors affecting survival included tumor diameter,anemia,serum tumor biomarkers,vascular or neural invasion,combined resection,LNR stage,N stage,and TNM stage(all P<0.05).The median survival time for those with LNR0,LNR1,LNR2 and LNR3 stage were 61,31,23 and 17 mo,respectively,and the differences were significant(P=0.000).Anemia,tumor biomarkers and LNR stage were independent prognostic factors for survival in multivariable analysis(all P<0.05).CONCLUSION The new LNR stage is uniquely based on number of metastatic LNs,with significant prognostic value for locally advanced GRC,and could better differentiate overall survival,compared with N stage. 展开更多
关键词 Gastric remnant cancer Positive lymph node ratio Clinicopathological characteristics PROGNOSIS
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The Effects of the Geometry of a Current Collector with an Equal Open Ratio on Output Power of a Direct Methanol Fuel Cell
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作者 Yingli Zhu Jiachi Xie +2 位作者 Mingwei Zhu Jun Zhang Miaomiao Li 《Energy Engineering》 EI 2024年第5期1161-1172,共12页
The open ratio of a current collector has a great impact on direct methanol fuel cell(DMFC)performance.Although a number of studies have investigated the influence of the open ratio of DMFC current collectors,far too ... The open ratio of a current collector has a great impact on direct methanol fuel cell(DMFC)performance.Although a number of studies have investigated the influence of the open ratio of DMFC current collectors,far too little attention has been given to how geometry(including the shape and feature size of the flow field)affects a current collector with an equal open ratio.In this paper,perforated and parallel current collectors with an equal open ratio of 50%and different feature sizes are designed,and the corresponding experimental results are shown to explain the geometry effects on the output power of the DMFC.The results indicate that the optimal feature sizes are between 2 and 2.5 mm for both perforated and parallel flow field in the current collectors with an equal open ratio of 50%.This means that for passive methanol fuel cells,to achieve the highest output power,the optimal feature size of the flow field in both anode and cathode current collectors is between 2 and 2.5 mm under the operating mode of this experiment.The effects of rib and channel position are also investigated,and the results indicate that the optimum pattern depends on the feature sizes of the flow field. 展开更多
关键词 Direct methanol fuel cell GEOMETRY open ratio current collector POSITION
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