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A two-sample Mendelian randomization study on the relationship of body weight,body mass index,and waist circumference with cardiac arrest
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作者 Tingting Xu Shaokun Wang +2 位作者 Liqiang Zhao Jiawen Wang Jihong Xing 《World Journal of Emergency Medicine》 2025年第2期129-135,共7页
BACKGROUND:This study aims to explore the causal relationship of body weight,body mass index(BMI),and waist circumference (WC) with the risk of cardiac arrest (CA) using two-sample Mendelian randomization (MR).METHODS... BACKGROUND:This study aims to explore the causal relationship of body weight,body mass index(BMI),and waist circumference (WC) with the risk of cardiac arrest (CA) using two-sample Mendelian randomization (MR).METHODS:Data were summarized using genome-wide association studies (GWAS).Twosample MR analyses were performed using the inverse variance weighting (IVW) method,the weighted median method,and the MR-Egger analysis.Heterogeneity test and sensitivity analysis were performed using Cochran’s Q test and the leave-one-out method,respectively.The Steiger test was used to detect reverse causality.Bayesian model-averaged MR was used to identify the most influential risk factors.RESULTS:A total of 13 GWAS data were collected for BMI,body weight and WC.IVW analyses showed a positive correlation of body weight,BMI,and WC with CA (all OR>1 and P<0.05),with MR-Egger and weighted median methods confirming the IVW findings.No horizontal pleiotropy or heterogeneity was observed.Sensitivity analysis indicated that no single nucleotide polymorphism(SNP) caused significant changes in overall causality.Bayesian model-averaged MR was also used to rank causality based on marginal inclusion probability (MIP),and the corresponding modelaveraged causal estimate (MACE) were confirmed,which indicated that WC (GWAS ID:ukb-b-9405)was the highest-ranked risk factor (MIP=0.119,MACE=0.011);its posterior probability was 0.057.A total of 14 sex-specific GWAS data on weight,BMI,and WC were analyzed in relationship with CA,and the MR results showed no significant effects of sex-specific factors.CONCLUSION:Body weight,BMI,and WC are causally associated with an increased risk of CA,with WC identified as the most important risk factor. 展开更多
关键词 Body weight Body mass index Waist circumference Cardiac arrest Mendelian randomization
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On Wiener Index of Power of Paths and Cycles
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作者 LIU Sai-hua LI Xiao-rong 《Chinese Quarterly Journal of Mathematics》 2025年第1期49-58,共10页
The Wiener index of a graph is defined to be the sum of the distances of all pairs of vertices in the graph.The kth power G^(k) of a graph G is the graph on V(G)and two vertices are adjacent if and only if their dista... The Wiener index of a graph is defined to be the sum of the distances of all pairs of vertices in the graph.The kth power G^(k) of a graph G is the graph on V(G)and two vertices are adjacent if and only if their distance in G is less or equal to k.In this paper,we computed the Wiener index of the kth power of paths and cycles for any k≥2. 展开更多
关键词 Wiener index kth power of a path kth power of a cycle
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Early peripheral perfusion index predicts 28-day outcome in patients with septic shock 被引量:2
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作者 Cheng Chi Hao Gong +2 位作者 Kai Yang Peng Peng Xiaoxia Zhang 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第5期372-378,共7页
BACKGROUND:To investigate the prognostic value of the peripheral perfusion index(PPI)in patients with septic shock.METHODS:This prospective cohort study,conducted at the emergency intensive care unit of Peking Univers... BACKGROUND:To investigate the prognostic value of the peripheral perfusion index(PPI)in patients with septic shock.METHODS:This prospective cohort study,conducted at the emergency intensive care unit of Peking University People's Hospital,recruited 200 patients with septic shock between January 2023 and August 2023.These patients were divided into survival(n=84)and death(n=116)groups based on 28-day outcomes.Clinical evaluations included laboratory tests and clinical scores,with lactate and PPI values assessed upon admission to the emergency room and at 6 h and 12 h after admission.Risk factors associated with mortality were analyzed using univariate and multivariate Cox regression analyses.Receiver operator characteristic(ROC)curve was used to assess predictive performance.Mortality rates were compared,and Kaplan-Meier survival plots were created.RESULTS:Compared to the survival group,patients in the death group were older and had more severe liver damage and coagulation dysfunction,necessitating higher norepinephrine doses and increased fl uid replacement.Higher lactate levels and lower PPI levels at 0 h,6 h,and 12 h were observed in the death group.Multivariate Cox regression identifi ed prolonged prothrombin time(PT),decreased 6-h PPI and 12-h PPI as independent risk factors for death.The area under the curves for 6-h PPI and 12-h PPI were 0.802(95%CI 0.742-0.863,P<0.001)and 0.945(95%CI 0.915-0.974,P<0.001),respectively,which were superior to Glasgow Coma Scale(GCS),Sequential Organ Failure Assessment(SOFA)scores(0.864 and 0.928).Cumulative mortality in the low PPI groups at 6 h and 12 h was signifi cantly higher than in the high PPI groups(6-h PPI:77.52%vs.22.54%;12-h PPI:92.04%vs.13.79%,P<0.001).CONCLUSION:PPI may have value in predicting 28-day mortality in patients with septic shock. 展开更多
关键词 Peripheral perfusion index Septic shock PROGNOSIS Predictive value
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Association between the cumulative triglyceride-glucose index and the recurrence of atrial fibrillation after radiofrequency catheter ablation 被引量:1
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作者 Qing YAN Jia-Qi LIANG +5 位作者 Yi-De YUAN Yuan LI Jia-Li FAN Wen-Huan WU Pan XU Jia-Hong XUE 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第2期200-210,共11页
BACKGROUND Triglyceride-glucose(TyG)index values are a new surrogate marker for insulin resistance.This study aimed to explore the relationship between cumulative TyG index values and atrial fibrillation(AF)recurrence... BACKGROUND Triglyceride-glucose(TyG)index values are a new surrogate marker for insulin resistance.This study aimed to explore the relationship between cumulative TyG index values and atrial fibrillation(AF)recurrence after radiofrequency catheter ablation(RFCA).METHODS A total of 576 patients with AF who underwent RFCA at the Second Affiliated Hospital of Xi'an Jiaotong University were included in this study.The participants were grouped based on cumulative TyG index values tertiles within 3 months after ablation.Cox regression and restricted cubic spline analyses were used to determine the relationship between cumulative TyG index values and AF recurrence.The predictive value of all risk factors was assessed by receiver operating curve analysis.RESULTS There were 375 patients completed the study(age:63.23±10.73 years,64.27%male).The risk of AF recurrence increased with increasing cumulative TyG index values tertiles.After adjusting for potential confounders,patients in the medium cumulative TyG index group[hazard ratio(HR)=4.949,95%CI:1.778–13.778,P=0.002]and the high cumulative TyG index group(HR=8.716,95%CI:3.371–22.536,P<0.001)had a higher risk of AF recurrence than those in the low cumulative TyG index group.The restricted cubic spline regression model also showed an increased risk of AF recurrence with increasing cumulative TyG index values.When considering cumulative TyG index values,left atrial diameter,and lactate dehydrogenase levels as a comprehensive factor,the model could effectively predict AF recurrence after RFCA[area under the curve(AUC)=0.847,95%CI:0.797–0.897,P<0.001].CONCLUSIONS Cumulative TyG index values were a risk factor for AF recurrence after RFCA.Monitoring longitudinal TyG index values may assist with optimized for risk stratification and outcome prediction for AF recurrence. 展开更多
关键词 ATRIAL FIBRILLATION index
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Predictive Value of Systemic Immune Inflammation Index, Aggregate Index of Systemic Inflammation, and Systemic Inflammation Response Index in Lower Extremity Deep Venous Thrombosis Following Severe Trauma
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作者 Peng-Fei Li Xin Lu +4 位作者 Yu-Qian Zhou Ke Wang Peng Yang Xiong-Hui Chen Feng Xu 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第4期241-248,共8页
Objective Venous thromboembolism is a highly prevalent condition after polytrauma,and recognized as an important factor contributing to poor prognosis.The aim of this study was to investigate the risk factors for lowe... Objective Venous thromboembolism is a highly prevalent condition after polytrauma,and recognized as an important factor contributing to poor prognosis.The aim of this study was to investigate the risk factors for lower extremity deep venous thrombosis(LEDVT)in a severely traumatized population and to evaluate their predictive value for LEDVT.Methods This was a retrospective,single-center observational study.All subjects were severely traumatized patients who were admitted to the Traumatic Intensive Care Unit from January 2021 to May 2024.Based on Doppler ultrasound findings of both lower extremities from the time of injury to 30 days post-injury,patients who developed LEDVT were enrolled in the LEDVT group,and those who did not develop LEDVT were enrolled in the NLEDVT group.Demographic,clinical,and laboratory data were collected upon admission.Multivariable logistic regression analysis was performed to identify risk factors for LEDVT.Receiver operating characteristic(ROC)curve was used to evaluate the overall fit of the final model.Results There were 56 patients enrolled in the LEDVT group and 81 patients in the NLEDVT group.Age,Aggregate Index of Systemic Inflammation(AISI),Systemic Inflammation Response Index(SIRI),ICU length of stay,and albumin were identified as independent risk factors for LEDVT(all P<0.05).The area under their ROC curves were 0.604,0.657,0.694,0.668,and 0.405,respectively.Combined model for early clinical prediction of LEDVT in severely traumatized patients by age,SIRI,AISI,and albumin resulted in an area under the ROC curve of 0.805(95%CI:0.73-0.88,SE=0.037).Conclusion The combination of age,SIRI,AISI,and albumin has a predictive value for LEDVT in severely traumatized patients. 展开更多
关键词 severe trauma Systemtic Immune Inflammation index Aggregate index of Systemic Inflammation Systemic Inflammation Response index lower extremity deep venous thrombosis
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Analysis and construction of evaluation index system of inter-provincial electricity spot markets
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作者 Hao Yue Yu Zhang +5 位作者 Jiahao Guo Yang Hu Chengmei Wei Heping Jia Dunnan Liu Dunjian Xie 《Global Energy Interconnection》 EI CSCD 2024年第6期697-706,共10页
Because of the contradiction between the scale of new energy installations and the continuous load growth in the central and eastern regions of China,the balance problems of the electricity market are becoming increas... Because of the contradiction between the scale of new energy installations and the continuous load growth in the central and eastern regions of China,the balance problems of the electricity market are becoming increasingly prominent,and it is urgent to solve such problems through inter-provincial electricity spot markets.First,the development history and construction status of the inter-provincial electricity spot market are summarized;second,the mechanism design of the inter-provincial electricity spot market is sorted out in terms of the market operation framework,transaction declaration,and clearing methods;subsequently,the evaluation index system of the inter-provincial electricity spot market is constructed,including four themes of electricity mutual aid and support,new energy consumption,economic benefits of market-based allocation,and social benefits of market-based allocation;finally,the operation of the inter-provincial electricity spot market is comprehensively analyzed by the algorithm based on the market operation data of 2022,which proves the feasibility and practicality of the proposed index system. 展开更多
关键词 Electricity market Spot market Inter-provincial spot market Evaluation index system
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Genetic variation and selection of 10-year-old Eucalyptus camaldulensis based on wind damage index and wood properties
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作者 Xiuhua Shang Zhihua Wu +2 位作者 Xiaoming Li Youshuang Wang Peijian Zhang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期173-184,共12页
Typhoons are becoming frequent and intense with ongoing climate change,threatening ecological security and healthy forest development in coastal areas.Eucalyptus of a predominant introduced species in southern China,f... Typhoons are becoming frequent and intense with ongoing climate change,threatening ecological security and healthy forest development in coastal areas.Eucalyptus of a predominant introduced species in southern China,faces significant growth challenges because of typhoon.Therefore,it is vital to investigate the variation of related traits and select superior breeding materials for genetic improvement.Variance,genetic parameter,and correlation analyses were carried out on wind damage indices and eight wood proper-ties in 88 families from 11 provenances of 10-year-old Euca-lyptus camaldulensis.The selection index equation was used for evaluating multiple traits and selecting superior prov-enances and family lines as future breeding material.The results show that all traits were highly significantly differ-ent at provenance and family levels,with the wind damage index having the highest coefficient of genetic variation.The heritability of each trait ranged from 0.48 to 0.87,with the wind damage index,lignin and hemicellulose contents,and microfibril angle having the highest heritabilities.The wind damage index had a positive genetic correlation with wood density,a negative correlation with lignin content,a negative phenotypic correlation and a negative genetic correlation with microfibril angle.Wind damage index and genetic progress in the selection of eight wood traits varied from 7.2%to 614.8%.Three provenances and 12 superior families were selected.The genetic gains of the wind damage index were 10.2%and 33.9%for provenances and families,and these may be starting material for genetic modification for wind resistance in eucalyptus and for their dissemination to typhoon-prone coastal areas of southern China. 展开更多
关键词 Eucalyptus camaldulensis Wind damage index Wood properties Genetic variation Comprehensive selection
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OFDM with Generalized Cascade Index Modulation for Secure Communications
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作者 Hu Zeng Jin Xiaopin +3 位作者 Yao Yudong Chen Fangjiong Wan Dehuan Liu Yun 《China Communications》 SCIE CSCD 2024年第10期210-225,共16页
Cascade index modulation(CIM) is a recently proposed improvement of orthogonal frequency division multiplexing with index modulation(OFDM-IM) and achieves better error performance.In CIM, at least two different IM ope... Cascade index modulation(CIM) is a recently proposed improvement of orthogonal frequency division multiplexing with index modulation(OFDM-IM) and achieves better error performance.In CIM, at least two different IM operations construct a super IM operation or achieve new functionality. First, we propose a OFDM with generalized CIM(OFDM-GCIM) scheme to achieve a joint IM of subcarrier selection and multiple-mode(MM)permutations by using a multilevel digital algorithm.Then, two schemes, called double CIM(D-CIM) and multiple-layer CIM(M-CIM), are proposed for secure communication, which combine new IM operation for disrupting the original order of bits and symbols with conventional OFDM-IM, to protect the legitimate users from eavesdropping in the wireless communications. A subcarrier-wise maximum likelihood(ML) detector and a low complexity log-likelihood ratio(LLR) detector are proposed for the legitimate users. A tight upper bound on the bit error rate(BER) of the proposed OFDM-GCIM, D-CIM and MCIM at the legitimate users are derived in closed form by employing the ML criteria detection. Computer simulations and numerical results show that the proposed OFDM-GCIM achieves superior error performance than OFDM-IM, and the error performance at the eavesdroppers demonstrates the security of D-CIM and M-CIM. 展开更多
关键词 cascade index modulation low-complexity detector maximum likelihood OFDM physical layer security
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Surface phonon resonance:A new mechanism for enhancing photonic spin Hall effect and refractive index sensor
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作者 程杰 汪承龙 +3 位作者 李一铭 张亚林 刘胜利 董鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期254-261,共8页
Metal-based surface plasmon resonance(SPR)plays an important role in enhancing the photonic spin Hall effect(SHE)and developing sensitive optical sensors.However,the very large negative permittivities of metals limit ... Metal-based surface plasmon resonance(SPR)plays an important role in enhancing the photonic spin Hall effect(SHE)and developing sensitive optical sensors.However,the very large negative permittivities of metals limit their applications beyond the near-infrared regime.In this work,we theoretically present a new mechanism to enhance the photonic SHE by taking advantage of SiC-supported surface phonon resonance(SPhR)in the mid-infrared regime.The transverse displacement of photonic SHE is very sensitive to the wavelength of incident light and the thickness of SiC layer.Under the optimal parameter setup,the calculated largest transverse displacement of SiC-based SPhR structure reaches up to 163.8 ym,which is much larger than the condition of SPR.Moreover,an NO_(2) gas sensor based on the SPhR-enhanced photonic SHE is theoretically proposed with the superior sensing performance.Both the intensity and angle sensitivity of this sensor can be effectively manipulated by varying the damping rate of SiC.The results may provide a promising paradigm to enhance the photonic SHE in the mid-infrared region and open up new opportunity of highly sensitive refractive index sensors. 展开更多
关键词 photonic spin Hall effect refractive index sensor surface phonon resonance SIC
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The influences of canopy temperature measuring on the derived crop water stress index
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作者 WANG Hongxi LI Fei +4 位作者 SHEN Hongtao LI Mengyu YIN Gongchao FANG Qin SHAO Liwei 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2024年第9期1503-1519,共17页
Crop water stress index(CWSI)is widely used for efficient irrigation management.Precise canopy temperature(T_(c))measurement is necessary to derive a reliable CWSI.The objective of this research was to investigate the... Crop water stress index(CWSI)is widely used for efficient irrigation management.Precise canopy temperature(T_(c))measurement is necessary to derive a reliable CWSI.The objective of this research was to investigate the influences of atmospheric conditions,settled height,view angle of infrared thermography,and investigating time of temperature measuring on the performance of the CWSI.Three irrigation treatments were used to create different soil water conditions during the 2020-2021 and 2021-2022 winter wheat-growing seasons.The CWSI was calculated using the CWSI-E(an empirical approach)and CWSI-T(a theoretical approach)based on the T_(c).Weather conditions were recorded continuously throughout the experimental period.The results showed that atmospheric conditions influenced the estimation of the CWSI;when the vapor pressure deficit(VPD)was>2000 Pa,the estimated CWSI was related to soil water conditions.The height of the installed infrared thermograph influenced the T_(c)values,and the differences among the T_(c)values measured at height of 3,5,and 10 m was smaller in the afternoon than in the morning.However,the lens of the thermometer facing south recorded a higher T_(c)than those facing east or north,especially at a low height,indicating that the direction of the thermometer had a significant influence on T_(c).There was a large variation in CWSI derived at different times of the day,and the midday measurements(12:00-15:00)were the most reliable for estimating CWSI.Negative linear relationships were found between the transpiration rate and CWSI-E(R^(2)of 0.3646-0.5725)and CWSI-T(R^(2)of 0.5407-0.7213).The relations between fraction of available soil water(FASW)with CWSI-T was higher than that with CWSI-E,indicating CWSI-T was more accurate for predicting crop water status.In addition,The R^(2)between CWSI-T and FASW at 14:00 was higher than that at other times,indicating that 14:00 was the optimal time for using the CWSI for crop water status monitoring.Relative higher yield of winter wheat was obtained with average seasonal values of CWSI-E and CWSI-T around 0.23 and 0.25-0.26,respectively.The CWSI-E values were more easily influenced by meteorological factors and the timing of the measurements,and using the theoretical approach to derive the CWSI was recommended for precise irrigation water management. 展开更多
关键词 Canopy temperature Measuring time Measuring height and direction Crop water stress index
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Independence Polynomials and the Merrifield-Simmons Index of Mono-Layer Cylindrical Grid Graphs
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作者 JI Lin-xing ZHANG Ke HU Wen-jun 《Chinese Quarterly Journal of Mathematics》 2024年第4期379-387,共9页
Research on the independence polynomial of graphs has been very active.However,the computational complexity of determining independence polynomials for general graphs remains NP-hard.Letα(G)be the independence number... Research on the independence polynomial of graphs has been very active.However,the computational complexity of determining independence polynomials for general graphs remains NP-hard.Letα(G)be the independence number of G and i(G;k)be the number of independent sets of order k in G,then the independence polynomial is defined as I(G;x)=∑_(k=0)^(α(G))i(G;k)x^(k),i(G;0)=1.In this paper,by utilizing the transfer matrix,we obtain an analytical expression for I(CGn;x)of mono-cylindrical grid graphs CGn and present a crucial proof of it.Moreover,we also explore the Merrifield-Simmons index and other properties of CGn. 展开更多
关键词 Independence polynomial Cylindrical grid graphs Transfer matrix Merrifield-Simmons index
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凉山州14个核桃品种主要经济指标及脂肪酸组成分析
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作者 金银春 任波 +2 位作者 胡定林 陈善波 余凌帆 《中国油脂》 北大核心 2025年第1期135-140,共6页
为全面评价、合理利用四川省凉山州现有核桃品种,对凉山州14个核桃品种的主要经济指标及脂肪酸组成进行了测定,计算了各指标变异系数和遗传多样性指数,并对各指标进行相关性分析和聚类分析。结果表明:14个核桃品种中,粗脂肪含量较高的... 为全面评价、合理利用四川省凉山州现有核桃品种,对凉山州14个核桃品种的主要经济指标及脂肪酸组成进行了测定,计算了各指标变异系数和遗传多样性指数,并对各指标进行相关性分析和聚类分析。结果表明:14个核桃品种中,粗脂肪含量较高的核桃品种有小圆、美姑大泡、冕漾等,蛋白质含量较高的核桃品种有陆佳、香酥、白鹤滩米核桃等;香酥为高油酸含量品种,利丰紫瓤、大凉山紫伊核桃晚熟2号为高亚油酸含量品种,盐源早、冬晚、利丰紫瓤为高α-亚麻酸含量品种,盐源早、冬晚、小圆的亚油酸与α-亚麻酸含量比值更接近4;出仁率、粗脂肪含量、棕榈酸含量的变异系数较低,均小于10%,说明这3个指标较稳定;主要经济指标与脂肪酸含量的遗传多样性指数的变化范围为1.57~2.14,其中,出仁率的遗传多样性指数最低,十七碳酸含量的遗传多样性指数最高;三径均值与单果质量存在极显著正相关性,蛋白质含量与α-亚麻酸含量存在显著负相关性,油酸含量与亚油酸含量存在极显著负相关性;经聚类分析,在欧氏距离为20时,14个核桃品种被分为2个组群,小圆、香酥聚为一组,其他12个品种聚为一组。综上,14个核桃品种均为当地的优良品种,可对油脂含量高、蛋白质含量高、脂肪酸比例合理及其他特异性指标有优势的品种有针对性地加以利用。 展开更多
关键词 凉山州 核桃 品种 经济指标 脂肪酸
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基于改进自编码解码网络的轨道不平顺评价方法
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作者 杨建伟 王小慧 +3 位作者 刘佩珊 杨飞 王金海 孙培文 《铁道学报》 北大核心 2025年第2期131-144,共14页
目前无砟轨道平顺性的评价方法只适用于中短波长,难以满足大范围动态复杂线路的变化需求。如果仅依靠单一波长轨检数据评价轨道状态,会导致其他波长局部波动或潜在病害不能被有效识别的现象。通过挖掘不同波长下的轨道不平顺信息,将深... 目前无砟轨道平顺性的评价方法只适用于中短波长,难以满足大范围动态复杂线路的变化需求。如果仅依靠单一波长轨检数据评价轨道状态,会导致其他波长局部波动或潜在病害不能被有效识别的现象。通过挖掘不同波长下的轨道不平顺信息,将深度学习方法与现有评价方法相融合,提出改进的自编码解码高斯生成对抗神经网络(DAGGAN)及自适应轨道质量指数方法(DAE_TQI),实现对轨道状态的实时监控。为验证方法的准确性和有效性,将其与其他方法进行对比,验证DAGGAN模型在识别单几何不平顺时的有效性,同时DAE_TQI方法可综合评价无砟轨道状态,结果可作为高速铁路轨道养护维修的理论依据。 展开更多
关键词 轨道不平顺 轨道质量指数 自编码解码网络 高斯对抗网络 自适应轨道质量指数
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正常肝脏组织摄取~(18)F-FAPI-04的影响因素分析
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作者 李阳 李艳 沈聪 《西安交通大学学报(医学版)》 北大核心 2025年第2期285-289,共5页
目的探讨正常肝脏组织摄取~(18)F-FAPI-04的影响因素。方法回顾性纳入行~(18)F-FAPI-04 PET/CT显像的患者77例,收集患者的既往病史,同时收集显像前1周内实验室检查,包括血细胞分类计数、肝功能和肾功能指标。手工测量~(18)F-FAPI-04 PET... 目的探讨正常肝脏组织摄取~(18)F-FAPI-04的影响因素。方法回顾性纳入行~(18)F-FAPI-04 PET/CT显像的患者77例,收集患者的既往病史,同时收集显像前1周内实验室检查,包括血细胞分类计数、肝功能和肾功能指标。手工测量~(18)F-FAPI-04 PET/CT图像上肝脏的最大标准摄取值(maximal standard uptake value,SUVmax),分析SUVmax与血液学指标的相关性。以肝脏的SUVmax为因变量,进行多因素线性回归,得到肝脏摄取~(18)F-FAPI-04的独立预测因素。结果肝脏SUVmax在是否吸烟、是否饮酒、是否化疗、有无活动性肿瘤及有无肝转移的组间差异均无统计学意义(P>0.05)。肝脏SUVmax与血细胞分类计数均无明显相关性(P>0.05),与谷丙转氨酶、γ-谷氨酰转肽酶、直接胆红素、球蛋白、血糖和肌酐正相关(r=0.196,P=0.047;r=0.180,P=0.027;r=0.196,P=0.015;r=0.171,P=0.032;r=0.296,P<0.001;r=0.270,P=0.001),与肾小球滤过率负相关(r=-0.209,P=0.009)。其中,血糖(β=0.100,P<0.001)、直接胆红素(β=0.021,P<0.001)和肌酐(β=0.003,P=0.018)是肝脏SUVmax的独立预测因子。结论肝脏摄取~(18)F-FAPI-04与谷丙转氨酶、γ-谷氨酰转肽酶、直接胆红素、球蛋白、血糖和肌酐呈正相关,与肾小球滤过率呈负相关。其中血糖、直接胆红素和肌酐是影响肝脏摄取~(18)F-FAPI-04的独立预测因子。 展开更多
关键词 PET/CT ~(18)F-FAPI-04 血细胞分类计数 肝功能指标 肾功能指标
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基于遥感指数的我国西部矿区生态质量监测——以彬长矿区为例 被引量:1
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作者 姚顽强 李悠 +4 位作者 郑俊良 蔺小虎 相里海龙 惠伯辰 李文欣 《金属矿山》 北大核心 2025年第1期259-266,共8页
我国西部矿区是煤炭资源开采的主要地区,也是最具代表性的生态脆弱区,探讨西部矿区自然生态环境的演变趋势及影响机制,对于矿区自然环境保护与有序恢复有着重要意义。以彬长矿区为例,通过遥感和GIS技术,利用Sentinel-2和Landsat 8遥感... 我国西部矿区是煤炭资源开采的主要地区,也是最具代表性的生态脆弱区,探讨西部矿区自然生态环境的演变趋势及影响机制,对于矿区自然环境保护与有序恢复有着重要意义。以彬长矿区为例,通过遥感和GIS技术,利用Sentinel-2和Landsat 8遥感影像数据,基于遥感生态指数(Remote Sensing Ecological Index,RSEI)模型,在深入剖析该矿区土地利用/覆被变化(Land Use/Cover Change,LUCC)和生态环境时空演变的基础上,分析了该矿区LUCC的生态质量。结果表明:①2017—2022年矿区LUCC结构上出现明显的转移特征,形成以林地、耕地和建设用地为主的新LUCC格局,并伴随着林地大范围转出为耕地和建设用地的情况,转移量约191.04 km^(2)。②5 a中,矿区生态环境质量呈下降趋势,RSEI由0.54降至0.47,研究发现矿区生态环境质量主要受绿度和干度指标因子影响。③2017—2022年矿区生态环境质量改善的面积占总面积的9%,生态环境质量恶化的面积占总面积的22%,分析结果可为西部矿区生态环境保护和修复提供参考。 展开更多
关键词 生态修复 遥感 GIS 遥感生态指数 土地利用/覆被变化 生态质量
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基于连续分布方向图和改进的Poincaré Index的指纹分类 被引量:20
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作者 聂桂军 吴陈 +1 位作者 叶锡君 徐荣青 《电子学报》 EI CAS CSCD 北大核心 2006年第5期947-952,共6页
本文提出了指纹连续分布方向图(场)的概念及其算法,连续分布方向图具有很好的连续性、渐变性、抗噪性和较高的精确度;对经典的PoincaréIndex计算公式和指纹奇异点检测算法进行了改进,改进后的PoincaréIndex不仅能精确表示向... 本文提出了指纹连续分布方向图(场)的概念及其算法,连续分布方向图具有很好的连续性、渐变性、抗噪性和较高的精确度;对经典的PoincaréIndex计算公式和指纹奇异点检测算法进行了改进,改进后的PoincaréIndex不仅能精确表示向量场的旋转角度,而且还能精确表示向量场的旋转方向,能够在像素级水平精确定位指纹奇异点(core点和delta点).在此基础上,提出了一种新的基于连续分布方向图和改进的PoincaréIn-dex的5类自动指纹分类算法,在江苏科技大学指纹库(含4000幅指纹)上的分类结果表明,本算法能抗任意角度的指纹图像旋转,成功地解决了指纹分类中的图像平移、旋转和形变不变性问题,分类正确率达到97.05%,具有较好的健壮性,满足实用要求. 展开更多
关键词 自动指纹识别系统 指纹分类 连续分布方向图 奇异点检测 POINCARÉ index
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旱地与补灌条件下不同基因型小麦耐旱性评价
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作者 孙宪印 吕广德 +9 位作者 亓晓蕾 徐加利 孙盈盈 米勇 牟秋焕 尹逊栋 张继波 王瑞霞 钱兆国 高明刚 《干旱地区农业研究》 北大核心 2025年第1期13-20,共8页
为在干旱胁迫条件下从不同小麦品系中筛选耐旱性强且具有高产稳产特性的基因型,采用随机区组设计,于2022—2023年在泰安市农业科学院马庄试验农场开展田间试验,以14个不同基因型小麦品系为材料,设置自然干旱和补灌条件2个处理,以旱地与... 为在干旱胁迫条件下从不同小麦品系中筛选耐旱性强且具有高产稳产特性的基因型,采用随机区组设计,于2022—2023年在泰安市农业科学院马庄试验农场开展田间试验,以14个不同基因型小麦品系为材料,设置自然干旱和补灌条件2个处理,以旱地与补灌条件下产量为基础,采用平均产量(MP)、几何平均产量(GMP)、抗旱系数(DRC)、抗旱指数(DRI)和干旱耐受指数(STI)共5个抗旱性指标对不同品系进行比较和抗旱性分级。结果表明,对比不同品系的干旱指标数值的大小与位次变化,V7、V14、V2和V12基因型排名靠前,具有高产、稳产特点。同时STI、GMP、MP指标与旱地产量和补灌产量均呈极显著正相关关系且表现出较好的产量一致性;主成分分析和聚类分析结果均进一步明确了这些基因型的耐旱及高产稳产特性。综上,在干旱与补灌条件下,STI、GMP、MP和DRI指标可用于耐旱高产基因型的鉴别和分级,综合利用5种抗旱指标筛选出耐旱高产品系分别为V7、V14、V2和V12,各品系抗旱性级别分别为1、2、2级和1级。 展开更多
关键词 小麦 基因型 干旱胁迫 主成分分析 聚类分析 耐旱性指标
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基于量化评估策略的分层干预对重症颅脑外伤术后患者血流变学指标及应激障碍程度的影响
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作者 徐欢欢 金小瑞 柳彦涛 《河南医学研究》 2025年第1期171-176,共6页
目的分析基于量化评估策略的分层干预对重症颅脑外伤术后患者血流变学指标及应激障碍程度的影响。方法选择2021年1月至2022年6月漯河市中心医院重症医学科收治的82例重症颅脑外伤术后患者进行研究,通过随机数字表法分为试验组、对照组,... 目的分析基于量化评估策略的分层干预对重症颅脑外伤术后患者血流变学指标及应激障碍程度的影响。方法选择2021年1月至2022年6月漯河市中心医院重症医学科收治的82例重症颅脑外伤术后患者进行研究,通过随机数字表法分为试验组、对照组,各41例。试验组接受基于量化评估策略的分层干预,对照组接受常规干预,两组均干预至出院,并随访6个月。比较两组康复情况,干预前、干预后营养指标、血流变学指标、运动功能、日常生活能力、昏迷程度,干预前、随访6个月后应激障碍,干预期间并发症及干预后护理满意度。结果试验组住院时间、重症医学科住院时间、肛门排便排气时间、肠鸣音恢复时间短于对照组(P<0.05)。较干预前,干预后两组血清总蛋白(TP)、转铁蛋白(TF)水平,肢体Fugl-Meyer运动功能测评量表(FMA)、Barthel指数评定(BI)、格拉斯哥昏迷评分法(GCS)评分升高,且试验组更高(P<0.05)。较干预前,干预后两组全血黏度、血浆黏度降低,且试验组更低(P<0.05)。较干预前,随访6个月后,两组主观评定、社会功能受损、警觉性增高、反复重现体验、回避症状评分降低,且试验组更低(P<0.05)。较对照组,试验组干预期间并发症发生率更低,干预后护理总满意率更高(P<0.05)。结论基于量化评估策略的分层干预可促进重症颅脑外伤术后患者康复,调节血流变学指标及营养指标,改善运动功能、日常生活能力、昏迷程度,降低远期应激障碍程度,控制并发症发生率,获得患者认可。 展开更多
关键词 颅脑外伤 重症 量化评估 分层干预 血流变学指标 应激障碍 营养指标
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基于Talbol理论的破碎岩石压缩变形及分形特征试验研究
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作者 孙文斌 田殿金 +2 位作者 薛彦超 张志 陈其勇 《矿业安全与环保》 北大核心 2025年第1期61-69,共9页
为研究侧限条件下不同轴向荷载、饱水状态及粒径级配3种因素对断层破碎岩体的压缩变形及分形特征的影响,以山东星村煤矿非导水断层取出的断层岩石为试样,利用自主研制的破碎岩石变形—渗流试验系统,开展侧限条件下不同Talbol幂指数n的... 为研究侧限条件下不同轴向荷载、饱水状态及粒径级配3种因素对断层破碎岩体的压缩变形及分形特征的影响,以山东星村煤矿非导水断层取出的断层岩石为试样,利用自主研制的破碎岩石变形—渗流试验系统,开展侧限条件下不同Talbol幂指数n的级配破碎岩石压缩变形试验。研究结果表明:随着轴向载荷逐级增大,破碎岩石轴向位移量增大,压缩碎胀系数和压实度变小;相同侧限轴向荷载条件下,饱水状态试样的轴向位移量和加载终点位移累积变形量比干燥状态的更大;随着级配指数增大,加载终点位移累积变形量变大;破碎岩石的质量分布系数C随Talbol幂指数n增大而增大,且随轴向荷载的增大而减小;破碎岩石分形维数D随Talbol幂指数n增大而减小,试验后分形维数增量随Talbol幂指数n增大而增大,即岩石破碎程度愈加剧烈。根据破碎岩体力学特征与分形特征将其变形过程划分为松散堆积、错位挤压、变形开裂、研磨破碎4个阶段,在加载前期岩石变形以颗粒滑动位移为主,加载后期变形以颗粒研磨破碎为主。 展开更多
关键词 破碎岩石 轴向荷载 分形维数 Talbol指数 压缩变形
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数字中医药古籍标引规则
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作者 张伟娜 李兵 +18 位作者 李斌 谢敬 董燕 龙伟 张楚楚 位通 刘思鸿 吴杨 李鸿涛 佟琳 陈广坤 董菲 王蕊 卢鹤 李萌 邓景鹏 王腾飞 李筱颖 张迪 《中国中医药信息杂志》 2025年第3期1-11,共11页
《数字中医药古籍标引规则》(T/CIATCM 119-2024)基于中医古典目录学理论知识、学科方法和实践应用,以数字中医药古籍为对象,对中医药学知识内容进行系统揭示,是构建中医药古籍智能检索系统重要的标引加工规范,可以为中医药古籍文献知... 《数字中医药古籍标引规则》(T/CIATCM 119-2024)基于中医古典目录学理论知识、学科方法和实践应用,以数字中医药古籍为对象,对中医药学知识内容进行系统揭示,是构建中医药古籍智能检索系统重要的标引加工规范,可以为中医药古籍文献知识的深度开发与创新利用提供支撑,不仅能促进中医药行业古籍资源共建共享,而且能推动中医药信息标准化建设与应用。本文件规定了数字中医药古籍基于原文内容进行自由标引的原则、方法与示例,适用于中医药专业图书馆及相关机构进行数字中医药古籍标引加工工作,以及各类型中医药古籍数据库的数据加工建设。 展开更多
关键词 中医药古籍 古籍数字化 标引规则
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