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Multiple factors influencing high-purity indium electrolytic refining
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作者 Hong-Qiang Fan Fei Li +5 位作者 Hong-Xing Zheng Wu-ji Pan Mei-Zhen Wu Yashar Behnamian Ju-Bo Peng Dong-Hai Lin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期148-160,共13页
The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,th... The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,the sodium chloride(NaCl)concentration,the current density,the gelatin concentration,the pH,and the electrode distance,were examined.Significant variations in impurity levels concerning gelatin concentration were observed.Both the gelatin and In3+concentration were moderately positively correlated with the Pb content.The Sb concentration was associated positively with the NaCl concentration,while the Ti concentration had an adverse correlation with the NaCl concentration.The Bi element content was positively linked to the electrode distance.As the current density increased,Cu,Pb,and Bi impurities initially rose and then eventually declined.Notably,a critical current density of 45 A·m^(-2) was identified in this behavior. 展开更多
关键词 High-purity indium ELECTROLYSIS multiple factors ELECTROCHEMISTRY Purification
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Examination of the Effective Factors on the Multiple Sclerosis Diseases
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作者 Rakeeh Ghaderi Azam Alikhademi 《Open Journal of Internal Medicine》 2024年第2期213-227,共15页
This study was an attempt to examine the effective factors of the Multiple Sclerosis diseases. The participants of the study were selected from among a total number of 45 men and women who were treated in a health cen... This study was an attempt to examine the effective factors of the Multiple Sclerosis diseases. The participants of the study were selected from among a total number of 45 men and women who were treated in a health center in Azarbayegan and Damavand in Iran. In order to study, the researchers applied various procedures to collect the data of the study. The participants were interviewed and filled out the questionnaires. After categorizing and classifying the collected information and data, it was processed and analyzed and the results are found. To test the research questions, a one-sample T-test was used to analyze the data. The role of hypo vitamin D as a possible risk factor for multiple sclerosis was reviewed. First, it was emphasized that hypo vitamin could be only one of the risk factors for multiple sclerosis and that numerous other environmental and genetic risk factors appear to interact and combine to trigger the disease. The main aim of this study was to examine the effective factors of Multiple Sclerosis diseases. The methodology of this research was to test the research questions;one-sample T-test was used to analyze the data. The findings of this study revealed that the factors of gender, cold weather, vitamin D deficiency, and age (between 30 - 59) were effective on the Multiple Sclerosis diseases. 展开更多
关键词 multiple Sclerosis Disease Effective factors
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Clinical Features of Renal Insufficiency due to Multiple Myeloma and Related Risk Factors 被引量:1
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作者 刘雪梅 徐金兰 +1 位作者 官旭华 刘丽秋 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第1期47-49,68,共4页
Objective: To study clinical features of the patients with multiple myeloma(MM) accompanied by renal insufficiency and investigate the related risk factors of renalimpairment. Methods: A control study of clinical char... Objective: To study clinical features of the patients with multiple myeloma(MM) accompanied by renal insufficiency and investigate the related risk factors of renalimpairment. Methods: A control study of clinical characteristics was performed between 91 patientswith renal insufficiency due to MM and 165 patients with normal renal function in MM during the sameperiod. The data were statistically analyzed by chi-square test and logistic regression analysis.Results: Renal insufficiency was the initial presentation in 48 (52.7%) of the 91 patients, and 30(62.5%) of the 48 patients were misdiagnosed. The prognosis of group with renal insufficiency wassignificantly poorer than that of group with normal renal function: mortality in 3 months, 3months-1 year was 26/91 vs 14/165 (P 【 0.0001), 14/91 vs 12/165 (P 【 0.05) respectively, andpatients survived 】 1 year was 18/91 vs 95/165 (P 【 0.0001). The incidence of hypercalcemia,hyperuricemic, severe anemia, high serum M-protein concentration and lytic bone lesions weresignificantly higher in renal insufficiency group than those in control group (P 【 0.05). Logisticregression analysis identified 5 risk factors of renal impairment, including, severe anemia(Exp(β)=13.819, P 【 0.0001), use of nephrotoxic drugs (Exp(β)=6.217, P = 0.001), high serumM-protein concentration (Exp(β) = 5.026, P = 0.001), male (Exp(β)=3.745, P=0.006), andhypercalcemia (Exp(β)=3A72, P=0.006), but age, serum density of uric acid, type of serum M-protein,and Bence Jones proteinuria were not significantly associated with renal insufficiency. Conclusion:Renal insufficiency was a common early complication of MM, which often resulted in misdiagnosis.The status of these patients tended to be very bad, with many other complications, when MM wasdiagnosed, so their prognosis was poor. The occurrence of renal insufficiency in patients with MMand hypercalcemia, severe anemia, high serum M-protein concentration, especially use of nephrotoxicdrugs should be alert. 展开更多
关键词 multiple myeloma renal insufficiency clinical feature risk factor
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Estimation of structure crack propagation based on multiple factors correction
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作者 朱林 贾民平 +1 位作者 姜长城 张菀 《Journal of Southeast University(English Edition)》 EI CAS 2017年第1期39-45,共7页
By deriving the stress concentration factor of theestimation approach for residual fatigue life’ an estimationapproach for structure crack propagation based on multiplefactors correction is proposed. Then’ the quant... By deriving the stress concentration factor of theestimation approach for residual fatigue life’ an estimationapproach for structure crack propagation based on multiplefactors correction is proposed. Then’ the quantitativeexpression among the structure factor’ stress ratio’ loadingtype’ the manufacture processing factor and the crackpropagation is achieved. The proposed approach iimplemented in a case study for an instance structure’ and theinfluences of correction factors on the crack propagation areanalyzed. Meanwhile’ the probabilistic method based onWeibull distribution probability density function is selected toevaluate the precision of the corrected estimation approach’and the probability density of results is calculated by theprobability density function. It is shown that the resultsestimated by the corrected approach is more precise than thoseestimated by the fracture mechanics, and they are closer to thetest data. 展开更多
关键词 estimation study crack propagation multiple factor correction probability density function
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Erectile dysfunction: on the efficacy of a phosphodiesterase inhibitor in patients with multiple risk factors 被引量:1
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作者 Harvey A.Rosenstock Samuel D.Axelrad 《Asian Journal of Andrology》 SCIE CAS CSCD 1999年第4期211-214,共4页
1 Introduction With the 1998 introduction of sildenafil (Viagra), the first available oral phosphodiesterase inhibitor, there
关键词 SILDENAFIL IMPOTENCE phosphodiesterase inhibitors multiple risk factors
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Solution of stress intensity factors of multiple cracks in plane elasticity with eigen COD formulation of boundary integral equation 被引量:1
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作者 郭钊 马杭 《Journal of Shanghai University(English Edition)》 CAS 2011年第3期173-179,共7页
The concept of eigen crack opening displacement (COD) can be defined as the COD of a crack in infinite plate under the tractions acting on the crack surface. By introducing this concept, the eigen COD formulation of... The concept of eigen crack opening displacement (COD) can be defined as the COD of a crack in infinite plate under the tractions acting on the crack surface. By introducing this concept, the eigen COD formulation of boundary integral equation is proposed in this paper, together with the solution procedures for multiple crack problems in plane elasticity. With the proposed approach, the multiple crack problems can be solved with the conventional displacement discontinuity boundary integral equations in an iterative fashion with a small size of system matrix as that in the numerical Green’s function (NGF) approach but without the trouble to determine the complementary solutions since the standard boundary element discretization on the crack surface is no longer required with the proposed approach. Some numerical examples computing the stress intensity factors are presented and compared with those in literature to show the accuracy and the effectiveness of the proposed approach. 展开更多
关键词 crack opening displacement (COD) multiple cracks stress intensity factor boundary integral equation ITERATION
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Peripheral blood stem cell mobilization in multiple myeloma: Growth factors or chemotherapy? 被引量:1
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作者 Whitney D Wallis Muzaffar H Qazilbash 《World Journal of Transplantation》 2017年第5期250-259,共10页
High-dose therapy followed by autologous hematopoietic stem cell(HSC) transplant is considered standard of care for eligible patients with multiple myeloma. The optimal colection strategy should be effective in procur... High-dose therapy followed by autologous hematopoietic stem cell(HSC) transplant is considered standard of care for eligible patients with multiple myeloma. The optimal colection strategy should be effective in procuring sufficient HSC while maintaining a low toxicity profile. Currently available mobilization strategies include growth factors alone,growth factors in combination with chemotherapy,or growth factors in combination with chemokine receptor antagonists; however,the optimal strategy has yet to be elucidated. Herein,we review the risks and benefits of each approach. 展开更多
关键词 multiple MYELOMA Stem cell MOBILIZATION Growth factors CHEMOTHERAPY
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Multiple regression analysis of risk factors related to radiation pneumonitis 被引量:1
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作者 Ling-Ling Shi Jiang-Hua Yang Hong-Fa Yao 《World Journal of Clinical Cases》 SCIE 2023年第5期1040-1048,共9页
BACKGROUND Radiation pneumonitis(RP)is a severe complication of thoracic radiotherapy that may lead to dyspnea and lung fibrosis,and negatively affects patients’quality of life.AIM To carry out multiple regression an... BACKGROUND Radiation pneumonitis(RP)is a severe complication of thoracic radiotherapy that may lead to dyspnea and lung fibrosis,and negatively affects patients’quality of life.AIM To carry out multiple regression analysis on the influencing factors of radiation pneumonitis.METHODS Records of 234 patients receiving chest radiotherapy in Huzhou Central Hospital(Huzhou,Zhejiang Province,China)from January 2018 to February 2021,and the patients were divided into either a study group or a control group based on the presence of radiation pneumonitis or not.Among them,93 patients with radiation pneumonitis were included in the study group and 141 without radiation pneumonitis were included in the control group.General characteristics,and radiation and imaging examination data of the two groups were collected and compared.Due to the statistical significance observed,multiple regression analysis was performed on age,tumor type,chemotherapy history,forced vital capacity(FVC),forced expiratory volume in the first second(FEV1),carbon monoxide diffusion volume(DLCO),FEV1/FVC ratio,planned target area(PTV),mean lung dose(MLD),total number of radiation fields,percentage of lung tissue in total lung volume(vdose),probability of normal tissue complications(NTCP),and other factors.RESULTS The proportions of patients aged≥60 years and those with the diagnosis of lung cancer and a history of chemotherapy in the study group were higher than those in the control group(P<0.05);FEV1,DLCO,and FEV1/FVC ratio in the study group were lower than those in the control group(P<0.05),while PTV,MLD,total field number,vdose,and NTCP were higher than in the control group(P<0.05).Logistic regression analysis showed that age,lung cancer diagnosis,chemotherapy history,FEV1,FEV1/FVC ratio,PTV,MLD,total number of radiation fields,vdose,and NTCP were risk factors for radiation pneumonitis.CONCLUSION We have identified patient age,type of lung cancer,history of chemotherapy,lung function,and radiotherapy parameters as risk factors for radiation pneumonitis.Comprehensive evaluation and examination should be carried out before radiotherapy to effectively prevent radiation pneumonitis. 展开更多
关键词 Radiation pneumonitis Influencing factors RADIOTHERAPY multiple regression analysis
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An Alternative Regression-Based Approach to Estimate the Crash Modification Factors of Multiple Treatments Using Before-and-After Data 被引量:1
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作者 Uditha Galgamuwa Sunanda Dissanayake 《Journal of Transportation Technologies》 2018年第4期273-290,共18页
Before-and-after methods have been effectively used in the road safety studies to estimate Crash Modification Factors (CMFs) of individual treatments as well as the multiple treatments on roadways. Since the common pr... Before-and-after methods have been effectively used in the road safety studies to estimate Crash Modification Factors (CMFs) of individual treatments as well as the multiple treatments on roadways. Since the common practice is to apply multiple treatments on road segments, it is important to have a method to estimate CMFs of individual treatment so that the effect of each treatment towards improving the road safety can be identified. Even though there are methods introduced by researchers to combine multiple CMFs or to isolate the safety effectiveness of individual treatment from CMFs developed for multiple treatments, those methods have to be tested before using them. This study considered two multiple treatments namely 1) Safety edge with lane widening 2) Adding 2 ft paved shoulders with shoulder rumble strips and/or asphalt resurfacing. The objectives of this research are to propose a regression-based method to estimate individual CMFs estimate CMFs using before-and-after Empirical Bayes method and compare the results. The results showed that having large sample size gives accurate predictions with smaller standard error and p-values of the considered treatments. Also, results obtained from regression method are similar to the EB method even though the values are not exactly the same. Finally, it was seen that the safety edge treatment reduces crashes by 15% - 25% and adding 2 ft shoulders with rumble strips reduces crashes by 25% - 49%. 展开更多
关键词 CRASH Modification factors for multiple TREATMENTS Negative BINOMIAL Models Safety Edge TREATMENTS Paved SHOULDERS Empirical BAYES Method
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Effects of Bortezomib and Dexamethasone combination on treating senile multiple myeloma and influence on immune suppressed factors and immune cell levels 被引量:1
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作者 Huan Wang Zhen Zhao +3 位作者 Tao Zhang Qing Ma Ye Xue Mei Xiong 《Journal of Hainan Medical University》 2017年第2期102-105,共4页
Objective:To investigate the effects of Bortezomib and Dexamethasone combination on treating senile multiple myeloma and influence on immune suppressed factors and immune cell levels.Methods:A total of 80 cases of pat... Objective:To investigate the effects of Bortezomib and Dexamethasone combination on treating senile multiple myeloma and influence on immune suppressed factors and immune cell levels.Methods:A total of 80 cases of patients with multiple myeloma treated in our hospital from Oct 2013 to Jul 2015 were selected as investigate subjects. They were randomly divided to be observation group consisted of 43 cases and control group consisted of 37 cases. For observation group, treatment of Bortezomib and Dexamethasone combination was provided. For control group, Vincristine + Epirubicin + Dexamethasone treatment was provided. After three courses, effects on two groups of patients were compared, and immune suppressed factors and immune cell levels before and after treatment in different periods were compared.Results:After three courses of treatment, the total effective rate in observation group was significantly higher than control group. Before treatment, IL-6, IL-17, TGF-β, CD3+CD4+, CD3+CD8+ and CD3+CD4+/CD3+CD8+ between the two group of patients were compared, no significant difference showed;After treatment for 6 weeks, IL-6, IL-17 levels in observation group were significantly decreased comparing with the same group before treatment;After treatment for 12 weeks, IL-6, IL-17 and TGF-β levels in observation group were significantly decreased comparing with the same group before treatment;After treatment, IL-6, IL-17 levels in observation group were significantly lower than control group at the same phase. After treatment for 12 weeks, CD3+CD4+, CD3+CD4+/CD3+CD8+ in observation group were significantly higher than the same group before treatment, and significantly higher than control group at the same phase;CD3+CD8+ in observation group was significantly lower than the same group before treatment, and significantly lower than control group at the same phase. Conclusion:Compared with Vincristine + Epirubicin + Dexamethasone treatment, Bortezomib and Dexamethasone combination on treating senile multiple myeloma had more significant effects, which deserves further clinical researches. 展开更多
关键词 multiple MYELOMA BORTEZOMIB DEXAMETHASONE IMMUNE suppressed factors IMMUNE cell
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Effect of Intensive Therapy of Multiple Factors Intervention on Vascular Complications in Type 2 Diabetes
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作者 吴汉妮 张淑玲 沈迪 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2003年第1期16-18,共3页
The effects of intensive versus regular therapy on incidence and progress of microalbuminuria in type 2 diabetes were compared. During a follow-up of 3 years, 96 cases of diabetes mellitus were randomized to intensive... The effects of intensive versus regular therapy on incidence and progress of microalbuminuria in type 2 diabetes were compared. During a follow-up of 3 years, 96 cases of diabetes mellitus were randomized to intensive and regular therapy groups. HbA 1c goal was same in the two groups, but the goal of blood pressure (Bp) and lipid was more strict in the intensive therapy group than in the regular therapy group. There was statistically significant difference in the incidence and progression of vascular complications between the two groups. Logistic stepwise-regression analysis (odds ration, OR) showed that there was significant difference in the progression of nephropathy (OR 0.24, 95 % CI 0.12-0.76), retinopathy (OR 0.38, 95 % CI 0.16-0.88), peripheral neuropathy (OR 0.42, 95 % CI 0.22-0.86) and autonomic neuropathy (OR 0.29, 95 % CI 0.12-0.86) between the two groups (P<0.01). It was concluded that intensive blood glucose controlling could retard diabetic vascular complications. Intensive therapy of multiple factors interventions (controlling Bp, regulating blood lipid, improving microcirculation) could decrease various risk factors for diabetic vascular complications. 展开更多
关键词 type 2 diabetes vascular complications multiple factors intervention intensive therapy
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A Collaboration Network Model with Multiple Evolving Factors
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作者 徐秀莲 刘春平 何大韧 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第4期159-162,共4页
To describe the empirical data of collaboration networks, several evolving mechanisms have been proposed, which usually introduce different dynamics factors controlling the network growth. These models can reasonably ... To describe the empirical data of collaboration networks, several evolving mechanisms have been proposed, which usually introduce different dynamics factors controlling the network growth. These models can reasonably reproduce the empirical degree distributions for a number of we11-studied real-world collaboration networks. On the basis of the previous studies, in this work we propose a collaboration network model in which the network growth is simultaneously controlled by three factors, including partial preferential attachment, partial random attachment and network growth speed. By using a rate equation method, we obtain an analytical formula for the act degree distribution. We discuss the dependence of the act degree distribution on these different dynamics factors. By fitting to the empirical data of two typical collaboration networks, we can extract the respective contributions of these dynamics factors to the evolution of each networks. 展开更多
关键词 of DE on in A Collaboration Network Model with multiple Evolving factors that with from for is been RDP
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Using Multiple Risk Factors and Generalized Linear Mixed Models with 5-Fold Cross-Validation Strategy for Optimal Carotid Plaque Progression Prediction
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作者 Qingyu Wang Dalin Tang +5 位作者 Liang Wang Gador Canton Zheyang Wu Thomas SHatsukami Kristen L Billiar Chun Yuan 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期74-75,共2页
Background Cardiovascular diseases are closely linked to atherosclerotic plaque development and rupture.Plaque progression prediction is of fundamental significance to cardiovascular research and disease diagnosis,pre... Background Cardiovascular diseases are closely linked to atherosclerotic plaque development and rupture.Plaque progression prediction is of fundamental significance to cardiovascular research and disease diagnosis,prevention,and treatment.Generalized linear mixed models(GLMM)is an extension of linear model for categorical responses while considering the correlation among observations.Methods Magnetic resonance image(MRI)data of carotid atheroscleroticplaques were acquired from 20 patients with consent obtained and 3D thin-layer models were constructed to calculate plaque stress and strain for plaque progression prediction.Data for ten morphological and biomechanical risk factors included wall thickness(WT),lipid percent(LP),minimum cap thickness(MinCT),plaque area(PA),plaque burden(PB),lumen area(LA),maximum plaque wall stress(MPWS),maximum plaque wall strain(MPWSn),average plaque wall stress(APWS),and average plaque wall strain(APWSn)were extracted from all slices for analysis.Wall thickness increase(WTI),plaque burden increase(PBI)and plaque area increase(PAI) were chosen as three measures for plaque progression.Generalized linear mixed models(GLMM)with 5-fold cross-validation strategy were used to calculate prediction accuracy for each predictor and identify optimal predictor with the highest prediction accuracy defined as sum of sensitivity and specificity.All 201 MRI slices were randomly divided into 4 training subgroups and 1 verification subgroup.The training subgroups were used for model fitting,and the verification subgroup was used to estimate the model.All combinations(total1023)of 10 risk factors were feed to GLMM and the prediction accuracy of each predictor were selected from the point on the ROC(receiver operating characteristic)curve with the highest sum of specificity and sensitivity.Results LA was the best single predictor for PBI with the highest prediction accuracy(1.360 1),and the area under of the ROC curve(AUC)is0.654 0,followed by APWSn(1.336 3)with AUC=0.6342.The optimal predictor among all possible combinations for PBI was the combination of LA,PA,LP,WT,MPWS and MPWSn with prediction accuracy=1.414 6(AUC=0.715 8).LA was once again the best single predictor for PAI with the highest prediction accuracy(1.184 6)with AUC=0.606 4,followed by MPWSn(1. 183 2)with AUC=0.6084.The combination of PA,PB,WT,MPWS,MPWSn and APWSn gave the best prediction accuracy(1.302 5)for PAI,and the AUC value is 0.6657.PA was the best single predictor for WTI with highest prediction accuracy(1.288 7)with AUC=0.641 5,followed by WT(1.254 0),with AUC=0.6097.The combination of PA,PB,WT,LP,MinCT,MPWS and MPWS was the best predictor for WTI with prediction accuracy as 1.314 0,with AUC=0.6552.This indicated that PBI was a more predictable measure than WTI and PAI. The combinational predictors improved prediction accuracy by 9.95%,4.01%and 1.96%over the best single predictors for PAI,PBI and WTI(AUC values improved by9.78%,9.45%,and 2.14%),respectively.Conclusions The use of GLMM with 5-fold cross-validation strategy combining both morphological and biomechanical risk factors could potentially improve the accuracy of carotid plaque progression prediction.This study suggests that a linear combination of multiple predictors can provide potential improvement to existing plaque assessment schemes. 展开更多
关键词 multiple Risk factors GENERALIZED Linear 5-Fold Cross-Validation STRATEGY AUC
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The investigation of multiple factors on elastic anisotropy of artificial shale based on the orthogonal experiment
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作者 Fei Gong Liang-Liang Gao +2 位作者 Guan-Gui Zou Su-Ping Peng Yi-Chen Song 《Petroleum Science》 SCIE EI CSCD 2023年第5期2773-2783,共11页
Elastic anisotropy of shales is critical to accurate constraints for rock physical models,quantitative interpretation and hydraulic fracturing.However,the causes of elastic anisotropy of shales are very complicated,an... Elastic anisotropy of shales is critical to accurate constraints for rock physical models,quantitative interpretation and hydraulic fracturing.However,the causes of elastic anisotropy of shales are very complicated,and the understanding of how multiple influence factors affect the elastic anisotropy of shales is still not clear.Hence,the orthogonal experiment,as an effective multiple factors experimental method,is adopted in this study to analyze the effect of multiple factors for shale elastic anisotropy.Three factors,clay content,organic matter(OM)content and compaction stress are selected as independent variables,the orthogonal test table L_(16)(4^(3))with four levels for each factor is adopted.According to the designed orthogonal table,sixteen artificial shales are constructed based on the cold-pressing method,and all the dry artificial shales are measured by the ultrasonic measurements.The influence of each factor on the elastic anisotropy and the sensitivity orders of three factors are obtained using the range analysis.The orders of sensitivity for selected factors follow the sequence clay content>compaction stress>OM content for velocity anisotropy parameters.The compaction mechanism of artificial shales is also discussed by the compaction factor,which are positively correlated with the velocity anisotropy parameters.The clay platelets orientation distribution function(ODF)of samples is evaluated by a theoretical model,the ODF coefficients are significantly affected by the clay content and compaction stress,and W200 are much more sensitive to these factors than W400.The results can provide a critical rock physics basis for quantitative interpretation and reservoir prediction of the low-maturity or maturity shale reservoir. 展开更多
关键词 SHALE Elastic anisotropy multiple factors Orthogonal design
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Numerical Comparison Research on the Solution of Stress Intensity Factors of Multiple Crack Problems
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作者 Guo Zhao 《Advances in Pure Mathematics》 2020年第12期706-727,共22页
A newly developed approach without crack surface discretization for modeling 2D solids with large number of cracks in linear elastic fracture mechanics is proposed with the eigen crack opening displacement (COD) bound... A newly developed approach without crack surface discretization for modeling 2D solids with large number of cracks in linear elastic fracture mechanics is proposed with the eigen crack opening displacement (COD) boundary integral equations in this paper. The eigen COD is defined as a crack in an infinite domain under fictitious traction acting on the crack surface. Respect to the computational accuracies and efficiencies, the multiple crack problems in finite and infinite plates are solved and compared numerically using three different kinds of boundary integral equations (BIEs): 1) the dual BIEs require crack surface discretization;2) the BIEs with numerical Green’s functions (NGF) without crack surface discretization, but have to solve a complementary matrix;3) the eigen crack opening displacement (COD) BIEs in the present paper. With the concept of eigen COD, the multiple crack problems can be solved by using a conventional displacement discontinuity boundary integral equation in an iterative fashion with a small size of system matrix as that in the NGF approach, but without troubles to determine the complementary matrix. Solution of the stress intensity factors of multiple crack problems is solved and compared in some numerical examples using the above three computational algorithms. Numerical results clearly demonstrate the numerical models of eigen COD BIEs have much higher efficiency, providing a newly numerical technique for multiple crack problems. Not only the accuracy and efficiency of computation can be guaranteed, but also the overall properties and local details can be obtained. In conclusion, the numerical models of eigen COD BIEs realize the simulations for multiple crack problems with large quantity of cracks. 展开更多
关键词 multiple Crack Problems Boundary Integral Equations Eigen Crack Opening Displacements Eshelby Matrix Stress Intensity factors
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Dominant early heading without yield drag in a sister-line BC breeding progeny DEH_229 is controlled by multiple genetic factors with maineffect loci
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作者 Muhiuddin Faruquee Qiang Zhang +7 位作者 Lubiao Zhang Linyun Xu Wensheng Wang Jiansan Chen Jianlong Xu Zhikang Li Binying Fu Tianqing Zheng 《The Crop Journal》 SCIE CSCD 2021年第2期400-411,共12页
Dominant early heading(DEH)in rice(Oryza sativa L.)is of interest in both breeding and genetics.The genetic mechanisms underlying DEH have remained largely unclear.We have developed a near-isogenic DEH line without yi... Dominant early heading(DEH)in rice(Oryza sativa L.)is of interest in both breeding and genetics.The genetic mechanisms underlying DEH have remained largely unclear.We have developed a near-isogenic DEH line without yield drag named DEH_229 by sister-line backcross(BC)breeding with MH63,a restorer,as the genetic background.We conducted a pilot genetic investigation under both short-day(SD)and long-day(LD)conditions.The DEH line harbored only 1.06%variation in the genome sequence relative to MH63.The variants were distributed throughout the genome.Using QTL mapping by sequencing(QTL-seq)on an F_(2) population derived from a cross of MH63×DEH_229,57 loci were detected under the SD condition.Joint mapping employing a genome-wide association study with accessions from the 3000 rice genome sequencing project(3K-RG),reduced the number of QTL by 43.9%.Using Rice Functional Genomics&Breeding(RFGB)database,the number of SNP cluster regions within the QTL regions reduced by 27.3%.Further comparison of the genome variation between DEH_229 and MH63 in addition to gene annotation information revealed a new DEH allele of DTH3 with multiple variable sites as a possible major factor underlying the early-heading phenotype of DEH_229.An InDel marker,ZMEH_1,was designed based on the variation between DEH_229 and MH63 within this region.It accounted for 86.0%of heading date variation under both SD and LD conditions in 109 randomly chosen progeny derived from extreme lines of the MH63×DEH_229 population.This study reveals the genetic complexity of DEH in the near-isogenic line and may provide useful material and marker information for plant molecular breeding. 展开更多
关键词 Dominant early heading Yield drag Sister-line BC breeding multiple genetic factors Cryptic genetic variation(CGV) Rice(Oryza sativa L.)
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Study on Influencing Factors of Childbearing-Aged Women’s Willingness to Have Multiple Children in China
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作者 Dandan Cheng Jiashan Tang 《Sociology Study》 2023年第2期63-74,共12页
The fertility rate of China has shown an overall decline trend,so the fully understanding of the factors affecting China’s fertility intention has become the focus of the research.Based on CFPS2020 data,the study sub... The fertility rate of China has shown an overall decline trend,so the fully understanding of the factors affecting China’s fertility intention has become the focus of the research.Based on CFPS2020 data,the study subjects were women of age between 20 and 49,who were born after the 1970s and were influenced by the family planning policy.Then,SMOTE-Catboost algorithm was used to construct a model.The results show that:(1)For the women’s willingness to have multiple children,the SMOTE-Catboost algorithm is more effective than the Catboost algorithm,and the classification accuracy is improved by 8 percentage points.(2)The factors influencing women’s willingness to have multiple children were ranked by social status,intergenerational care,education level and age.Women with high social status are more willing to have multiple children;All-day intergenerational care has a positive effect on women’s willingness to have multiple children.And women’s willingness to have multiple children declines with the rise of education level but increases with age.(3)Combined with the CFPS2018 data,the influencing factors changed over time.In 2018,the important factors related to women’s willingness to have multiple children were mainly related to economic,within which the income ranked locally is the most important one.In 2020,the most important factor changed to be social status while economic became less important. 展开更多
关键词 SMOTE algorithm Catboost algorithm fertility intention to have multiple child influencing factors China
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Multiple Risk Factor Clustering and Risk of Hypertension in the Mongolian Ethnic Population of China 被引量:11
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作者 CHANG-QING YING SONG-BIN FU +5 位作者 QUN XU WEI-JUN TONG MING-WU FANG ZHENG-LAI WU CHANG-CHUN OIU YONG-HONG ZHANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第5期381-385,共5页
Objective To evaluate whether the clustering of risk factors, both environmental and genetic, increases the risk of essential hypertension (EH) and the accumulation of risk factors influences the blood pressure leve... Objective To evaluate whether the clustering of risk factors, both environmental and genetic, increases the risk of essential hypertension (EH) and the accumulation of risk factors influences the blood pressure level in normotensives. Methods On the basis of a prevalence survey, 501 subjects of Mongolian ethnicity (243 hypertensives and 258 normotensives) who were not related to each other were selected to conduct a case-control study. All subjects were interviewed with questionnaires and their blood specimens were collected. Renin gene insertion/deletion (I/D) polymorphism, a new genetic marker, was genotyped with PCR and polyacrylamide gel electrophoresis. Results Overweight, alcohol consumption, and renin gene I/D polymorphism were significant risk factors of EH (P〈0.05). The odds ratios (OR) for the number of risk factors were 2.39 (95%CI: 0.98-6.74) for one risk factor, 5.03 (95%CI: 2.06-14.18) for two, and 6.09 (95%CI: 1.85-22.38) for three respectively after adjusting for age and sex. In normotensives, age- and sex-adjusted mean blood pressures increased with more accumulation of risk factors. However, there were no significant differences among the different blood pressure levels according to the number of risk factors (P〉0.05). Conclusion Overweight, alcohol consumption, and renin gene I/D polymorphism are risk factors of EH in the Mongolian ethnic population of China. The accumulation of the risk factors causes a sharp increase of the risk of EH. 展开更多
关键词 Essential hypertension multiple risk factors OVERWEIGHT Alcohol consumption Renin gene polymorphism
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Role of Brain-derived Neurotrophic Factor in Bone Marrow Angiogenesis in Multiple Myeloma 被引量:1
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作者 褚章波 孙春艳 +2 位作者 杨迪 陈蕾 胡豫 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2013年第4期485-490,共6页
Summary: This study examined the expression of brain-derived neurotrophic factor (BDNF) in multiple myeloma (MM) and its role in bone marrow angiogenesis. The peripheral blood plasma was harvested from 71 MM pati... Summary: This study examined the expression of brain-derived neurotrophic factor (BDNF) in multiple myeloma (MM) and its role in bone marrow angiogenesis. The peripheral blood plasma was harvested from 71 MM patients and 63 patients without hematological malignancy. The BDNF level in the blood plasma was determined by ELISA. Human bone marrow endothelial cells (HBMECs) were cul- tured. The mRNA and protein expression levels of the BDNF receptor TrkB in HBMECs were detected by using RT-PCR and flow cytometry, respectively. The viability of HBMECs treated with recombinant human (rh) BDNF or not was measured by using MTT assay. The migration of HBMECs in the presence of rhBDNF or not was determined by modified Boyden chamber assay. In vitro tube formation assay was used to assess the effect of rhBDNF on HBMECs differentiation. The results of ELISA revealed that the BDNF level was significantly higher in peripheral blood plasma of MM patients than in that of control patients (4.39±0.67 vs. 1.96±0.39 ng/mL, P〈0.05). The BDNF receptor TrkB was ex- pressed in HBMECs at mRNA and protein level. MTT assay manifested that rhBDNF could signifi- cantly concentration-dependently promote the HBMECs proliferation. The number of HBMECs treated with 160 ng/mL rhBDNF for 48 h was 1.57±0.10 folds higher than that in control group (P〈0.05). Moreover, rhBDNF could enhance HBMECs migration in a concentration-dependent manner and the maximal migration was reached in the presence of 100 ng/mL rhBDNF. The migration indexes were 1.40±10.11, 1.64±0.16, 2.06±0.25 and 2.18±0.21 in 25, 50, 100 ng/mL rhBDNF groups and 25 ng/mL rhVEGF group, respectively. In vitro tube formation assay demonstrated that the area of the formed tu- bular structure was increased with the rhBDNF concentration. In control group, there was no formation of intact tubular structure and the HBMECs on the matrigel were irregularly dispersed. HBMECs treated with 100 ng/mL rhBDNF could form intact tubular structure and the area and the diameter of tubes were significantly greater than those in control group (P〈0.05). There was no significant differ- ence in the formed tubular area between 25 ng/mL VEGF group and 100 ng/mL rhBDNF group. It was concluded that BDNF plays an important role in myeloma cell-induced angiogenesis, and it may be- come a new target of anti-angiogenesis treatment for MM. 展开更多
关键词 multiple myeloma brain-derived neurotrophic factor ANGIOGENESIS bone marrow endo-thelial cells
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Elevated serum growth differentiation factor 15 in multiple system atrophy patients:A case control study 被引量:1
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作者 Tao Yue Hui Lu +4 位作者 Xiao-Mei Yao Xia Du Ling-Ling Wang Dan-Dan Guo Yi-Ming Liu 《World Journal of Clinical Cases》 SCIE 2020年第12期2473-2483,共11页
BACKGROUND Multiple system atrophy(MSA) is a serious progressive neurodegenerative disease. Early diagnosis of MSA is very difficult, and diagnostic biomarkers are limited. Growth differentiation factor 15(GDF15) is i... BACKGROUND Multiple system atrophy(MSA) is a serious progressive neurodegenerative disease. Early diagnosis of MSA is very difficult, and diagnostic biomarkers are limited. Growth differentiation factor 15(GDF15) is involved in the differentiation and progression of the central nervous system, and is widely distributed in peripheral blood, which may be a novel biomarker for MSA.AIM To determine serum GDF15 levels, related factors and their potential diagnostic value in MSA patients, compared with Parkinson’s disease(PD) patients and healthy controls.METHODS A case-control study was conducted, including 49 MSA patients, 50 PD patients and 50 healthy controls. Serum GDF15 levels were measured by human enzymelinked immunosorbent assay, and the differences between the MSA, PD and control groups were analyzed. Further investigations were performed in different MSA subgroups according to age of onset, sex, clinical subtypes, diagnostic criteria, and disease duration. Receiver-operating characteristic curve analysiswas used to evaluate the diagnostic value of GDF15, especially for the differential diagnosis between MSA and PD.RESULTS Serum GDF15 levels were significantly higher in MSA patients than in PD patients and healthy controls(P = 0.000). Males and those with a disease duration of more than three years showed higher serum GDF15 levels(P = 0.043 and 0.000;respectively). Serum GDF15 levels may be a potential diagnostic biomarker for MSA patients compared with healthy controls and PD patients(cutoff: 470.42 pg/m L, sensitivity: 85.7%, specificity: 88.0%;cutoff: 1075.91 pg/m L, sensitivity:51.0%, specificity: 96.0%;respectively).CONCLUSION Serum GDF15 levels are significantly higher in MSA patients and provide suggestions on the etiology of MSA. 展开更多
关键词 multiple system atrophy Parkinson’s disease Serum growth differentiation factor 15 BIOMARKER Receiver-operating characteristic curve Neurodegenerative disease
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