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Causal relationship between multiple types of food intake and myopia:a Mendelian randomization study
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作者 Sha-Sha Zhang Jiao-Jiao Liang +4 位作者 Yun Feng Xia Hong Yi-Jia Zhao Ling Chen Ping Lin 《International Journal of Ophthalmology(English edition)》 2025年第9期1718-1729,共12页
AIM:To investigate the causal relationship between dietary intake and myopia using Mendelian randomization(MR)analysis.METHODS:Genome-wide association study(GWAS)data from the IEU Open GWAS database were utilized to e... AIM:To investigate the causal relationship between dietary intake and myopia using Mendelian randomization(MR)analysis.METHODS:Genome-wide association study(GWAS)data from the IEU Open GWAS database were utilized to examine associations between myopia and various dietary factors.MR analysis,incorporating both univariable and multivariable approaches,assessed the impact of food intake on myopia risk through five analytical methods,with inverse variance weighted(IVW)serving as the primary reference.Sensitivity analyses,including heterogeneity assessment,horizontal pleiotropy evaluation,and leave-oneout analysis,were conducted to validate the MR findings.RESULTS:Univariable MR analysis identified a causal link between food intake and myopia.Consumption of breaded fish,canned soup,sweet biscuits,and certain fruits correlated with a lower risk of myopia,whereas intake of low-calorie hot chocolate and cereal was associated with an increased risk.Multivariable MR analysis further confirmed that breaded fish consumption exerted a direct protective effect against myopia,particularly when consumed alongside other dietary components.These findings highlight the intricate interplay between specific dietary factors and myopia development,offering valuable insights for further research.CONCLUSION:MR analysis provides evidence supporting a potential causal relationship between breaded fish intake and myopia,underscoring its relevance in targeted myopia prevention strategies. 展开更多
关键词 MYOPIA genome-wide association study food intakes univariable Mendelian randomization analysis multivariable Mendelian randomization analysis
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Exploration of influential factors about Qi-deficiency constitution of Traditional Chinese Medicine based on multi-methods
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作者 LUO Yue CHENG Xiaoen +4 位作者 JIANG Luxia SU Biliang ZHAO Yuxin OU Jintao WEN Chuanbiao 《Journal of Traditional Chinese Medicine》 2025年第3期693-701,共9页
OBJECTIVE:To find more influencing factors Qideficiency constitution of Traditional Chinese Medicine(TCM)using dynamic and comprehensive information.METHODS:Because grey relational analysis(GRA)is good at processing i... OBJECTIVE:To find more influencing factors Qideficiency constitution of Traditional Chinese Medicine(TCM)using dynamic and comprehensive information.METHODS:Because grey relational analysis(GRA)is good at processing incomplete information and has no special requirements for sample size and distribution.We acquired 2122 pieces of valid Qi-deficiency constitution dynamic data after preprocessing,and used GRA combing withχ~2 test and multivariate logistic regression analysis to discover and sort the influencing factors of Qideficiency constitution.RESULTS:For the calculation results of GRA,there were 10(62.5%)aspects whose grey correlation degrees were greater than 0.6.The results ofχ~2 test showed that all the above 10 aspects were statistically significant with Qideficiency constitution.The analysis results of multivariate logistic regression analysis showed the following factors were positively correlated with Qi-deficiency constitution:premature birth,sleeping late and getting up early,sleeping late and getting up late,irregular sleeping,sleeping 6.0-6.9 h per day,artificial feeding,female,age at 18-19,and father's age at 18-19 years old when a baby at birth.The following factors were negatively correlated with Qi-deficiency constitution:sleeping 8.0-8.9 h per day and≥9.0 h per day,and age at 30-39 and 40-49 years old.CONCLUSIONS:It is necessary to pay attention to these innate and acquired information of individuals which may lead to Qi-deficiency constitution.And our research also provides a novel methodological thinking for analyzing the influential factors of TCM constitution. 展开更多
关键词 Qi-deficiency constitution influencing factors grey relational analysis univariate analysis multivariate analysis
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Risk factors and predictive modeling of early postoperative liver function abnormalities
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作者 Lin Zhong Hao-Yuan Wang +5 位作者 Xiao-Na Li Qiong Ling Ning Hao Xiang-Yu Li Gao-Feng Zhao Min Liao 《World Journal of Hepatology》 2025年第8期233-243,共11页
BACKGROUND Research has shown that several factors can influence postoperative abnormal liver function;however,most studies on this issue have focused specifically on hepatic and cardiac surgeries,leaving limited rese... BACKGROUND Research has shown that several factors can influence postoperative abnormal liver function;however,most studies on this issue have focused specifically on hepatic and cardiac surgeries,leaving limited research on contributing factors in other types of surgeries.AIM To identify the risk factors for early postoperative abnormal liver function in multiple surgery types and construct a risk prediction model.METHODS This retrospective cohort study involved 3720 surgical patients from 5 surgical departments at Guangdong Provincial Hospital of Traditional Chinese Medicine.Patients were divided into abnormal(n=108)and normal(n=3612)groups based on liver function post-surgery.Univariate analysis and LASSO regression screened variables,followed by logistic regression to identify risk factors.A prediction model was constructed based on the variables selected via logistic re-gression.The goodness-of-fit of the model was evaluated using the Hosm-er–Lemeshow test,while discriminatory ability was measured by the area under the receiver operating characteristic curve.Calibration curves were plotted to visualize the consistency between predicted probabilities and observed outcomes.RESULTS The key factors contributing to abnormal liver function after surgery include elevated aspartate aminotransferase and alanine aminotransferase levels and reduced platelet counts pre-surgery,as well as the sevoflurane use during the procedure,among others.CONCLUSION The above factors collectively represent notable risk factors for postoperative liver function injury,and the prediction model developed based on these factors demonstrates strong predictive efficacy. 展开更多
关键词 Perioperative period Abnormal liver function Risk factor Univariate analysis Risk prediction model
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Berg Balance Scale score is a valuable predictor of all-cause mortality among acute decompensated heart failure patients
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作者 Yu-Xuan FAN Jing-Jing CHENG +7 位作者 Zhi-Qing FAN Jing-Jin LIU Wen-Juan XIU Meng-Yi ZHAN Lin LUO Guang-He LI Le-Min WANG Yu-Qin SHEN 《Journal of Geriatric Cardiology》 2025年第6期555-562,共8页
OBJECTIVE To investigate possible associations between physical function assessment scales,such as Short Physical Performance Battery(SPPB)and Berg Balance Scale(BBS),with all-cause mortality in acute decompensated he... OBJECTIVE To investigate possible associations between physical function assessment scales,such as Short Physical Performance Battery(SPPB)and Berg Balance Scale(BBS),with all-cause mortality in acute decompensated heart failure(ADHF)patients.METHODS A total of 108 ADHF patients were analyzed from October 2020 to October 2022,and followed up to May 2023.The association between baseline clinical characteristics and all-cause mortality was analyzed by univariate Cox regression analysis,while for SPPB and BBS,univariate Cox regression analysis was followed by receiver operating characteristic curves,in which the area under the curve represented their predictive accuracy for all-cause mortality.Incremental predictive values for both physical function assessments were measured by calculating net reclassification index and integrated discrimination improvement scores.Optimal cutoff value for BBS was then identified using restricted cubic spline plots,and survival differences below and above that cut-off were compared using Kaplan-Meier survival curves and the log-rank test.The clinical utility of BBS was measured using decision curve analysis.RESULTS For baseline characteristics,age,female,blood urea nitrogen,as well as statins,angiotensin-converting enzyme inhibitors,angiotensin II receptor blockers,or angiotensin receptor-neprilysin inhibitors,were predictive for all-cause mortality for ADHF patients.With respect to SPPB and BBS,higher scores were associated with lower all-cause mortality rates for both assessments;similar area under the curves were measured for both(0.774 for SPPB and 0.776 for BBS).Furthermore,BBS≤36.5 was associated with significantly higher mortality,which was still applicable even adjusting for confounding factors;BBS was also found to have great clinical utility under decision curve analysis.CONCLUSIONS BBS or SPPB could be used as tools to assess physical function in ageing ADHF patients,as well as prognosticate on all-cause mortality.Moreover,prioritizing the improvement of balance capabilities of ADHF patients in cardiac rehabilitation regimens could aid in lowering mortality risk. 展开更多
关键词 physical function assessment scalessuch Acute Decompensated Heart Failure All Cause Mortality Physical Function Assessment berg balance scale bbs short physical performance battery sppb univariate cox regression analysiswhile Short Physical Performance Battery
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Review of Recent Trends in the Hybridisation of Preprocessing-Based and Parameter Optimisation-Based Hybrid Models to Forecast Univariate Streamflow
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作者 Baydaa Abdul Kareem Salah L.Zubaidi +1 位作者 Nadhir Al-Ansari Yousif Raad Muhsen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期1-41,共41页
Forecasting river flow is crucial for optimal planning,management,and sustainability using freshwater resources.Many machine learning(ML)approaches have been enhanced to improve streamflow prediction.Hybrid techniques... Forecasting river flow is crucial for optimal planning,management,and sustainability using freshwater resources.Many machine learning(ML)approaches have been enhanced to improve streamflow prediction.Hybrid techniques have been viewed as a viable method for enhancing the accuracy of univariate streamflow estimation when compared to standalone approaches.Current researchers have also emphasised using hybrid models to improve forecast accuracy.Accordingly,this paper conducts an updated literature review of applications of hybrid models in estimating streamflow over the last five years,summarising data preprocessing,univariate machine learning modelling strategy,advantages and disadvantages of standalone ML techniques,hybrid models,and performance metrics.This study focuses on two types of hybrid models:parameter optimisation-based hybrid models(OBH)and hybridisation of parameter optimisation-based and preprocessing-based hybridmodels(HOPH).Overall,this research supports the idea thatmeta-heuristic approaches precisely improveML techniques.It’s also one of the first efforts to comprehensively examine the efficiency of various meta-heuristic approaches(classified into four primary classes)hybridised with ML techniques.This study revealed that previous research applied swarm,evolutionary,physics,and hybrid metaheuristics with 77%,61%,12%,and 12%,respectively.Finally,there is still room for improving OBH and HOPH models by examining different data pre-processing techniques and metaheuristic algorithms. 展开更多
关键词 Univariate streamflow machine learning hybrid model data pre-processing performance metrics
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关于计算机辅助普通话水平测试的统计分析 被引量:1
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作者 汲剑锐 洪冉 李波 《湖北工业大学学报》 2011年第3期7-9,共3页
探讨了计算机在普通话水平测试中的应用.首先针对计算机辅助普通话水平测试结果进行了信度的分析,进而用两种不同的统计方法证明了普通话的测试成绩并不服从正态分布,最后用两种不同的统计方法证实了复审数据的科学性且复审对于机测的... 探讨了计算机在普通话水平测试中的应用.首先针对计算机辅助普通话水平测试结果进行了信度的分析,进而用两种不同的统计方法证明了普通话的测试成绩并不服从正态分布,最后用两种不同的统计方法证实了复审数据的科学性且复审对于机测的必要性. 展开更多
关键词 信度 univariate检验 wilcoxon符号秩检验
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Factors predicting sensory and motor recovery after the repair of upper limb peripheral nerve injuries 被引量:13
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作者 Bo He Zhaowei Zhu +6 位作者 Qingtang Zhu Xiang Zhou Canbin Zheng Pengliang Li Shuang Zhu Xiaolin Liu Jiakai Zhu 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第6期661-672,共12页
OBJECTIVE: To investigate the factors associated with sensory and motor recovery after the repair of upper limb peripheral nerve injuries. DATA SOURCES: The online PubMed database was searched for English articles d... OBJECTIVE: To investigate the factors associated with sensory and motor recovery after the repair of upper limb peripheral nerve injuries. DATA SOURCES: The online PubMed database was searched for English articles describing outcomes after the repair of median, ulnar, radial, and digital nerve injuries in humans with a publication date between 1 January 1990 and 16 February 2011. STUDY SELECTION: The following types of article were selected: (1) clinical trials describ- ing the repair of median, ulnar, radial, and digital nerve injuries published in English; and (2) studies that reported sufficient patient information, including age, mechanism of injury, nerve injured, injury location, defect length, repair time, repair method, and repair materials. SPSS 13.0 software was used to perform univariate and multivariate logistic regression analyses and to in- vestigate the patient and intervention factors associated with outcomes. MAIN OUTCOME MEASURES: Sensory function was assessed using the Mackinnon-Dellon scale and motor function was assessed using the manual muscle test. Satisfactory motor recovery was defined as grade M4 or M5, and satisfactory sensory recovery was defined as grade S3+ or S4. RESULTS: Seventy-one articles were included in this study. Univariate and multivariate logistic regression analyses showed that repair time, repair materials, and nerve injured were inde- pendent predictors of outcome after the repair of nerve injuries (P 〈 0.05), and that the nerve injured was the main factor affecting the rate of good to excellent recovery. CONCLUSION: Predictors of outcome after the repair of peripheral nerve injuries include age, gender, repair time, repair materials, nerve injured, defect length, and duration of follow-up. 展开更多
关键词 nerve regeneration peripheral nerve injury outcome predictors nerve repair upperlimb univariate analysis PROGNOSIS 863 Program neural regeneration
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Metocean Design Parameter Estimation for Fixed Platform Based on Copula Functions 被引量:4
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作者 ZHAI Jinjin YIN Qilin DONG Sheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第4期635-648,共14页
Considering the dependent relationship among wave height,wind speed,and current velocity,we construct novel trivariate joint probability distributions via Archimedean copula functions.Total 30-year data of wave height... Considering the dependent relationship among wave height,wind speed,and current velocity,we construct novel trivariate joint probability distributions via Archimedean copula functions.Total 30-year data of wave height,wind speed,and current velocity in the Bohai Sea are hindcast and sampled for case study.Four kinds of distributions,namely,Gumbel distribution,lognormal distribution,Weibull distribution,and Pearson Type III distribution,are candidate models for marginal distributions of wave height,wind speed,and current velocity.The Pearson Type III distribution is selected as the optimal model.Bivariate and trivariate probability distributions of these environmental conditions are established based on four bivariate and trivariate Archimedean copulas,namely,Clayton,Frank,Gumbel-Hougaard,and Ali-Mikhail-Haq copulas.These joint probability models can maximize marginal information and the dependence among the three variables.The design return values of these three variables can be obtained by three methods:univariate probability,conditional probability,and joint probability.The joint return periods of different load combinations are estimated by the proposed models.Platform responses(including base shear,overturning moment,and deck displacement) are further calculated.For the same return period,the design values of wave height,wind speed,and current velocity obtained by the conditional and joint probability models are much smaller than those by univariate probability.Considering the dependence among variables,the multivariate probability distributions provide close design parameters to actual sea state for ocean platform design. 展开更多
关键词 Archimedean copulas univariate distribution bivariate distribution trivariate distribution platform response
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Multi-population and diffusion UMDA for dynamic multimodal problems 被引量:3
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作者 Yan Wu Yuping Wang +1 位作者 Xiaoxiong Liu Jimin Ye 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第5期777-783,共7页
In dynamic environments,it is important to track changing optimal solutions over time.Univariate marginal distribution algorithm(UMDA) which is a class algorithm of estimation of distribution algorithms attracts mor... In dynamic environments,it is important to track changing optimal solutions over time.Univariate marginal distribution algorithm(UMDA) which is a class algorithm of estimation of distribution algorithms attracts more and more attention in recent years.In this paper a new multi-population and diffusion UMDA(MDUMDA) is proposed for dynamic multimodal problems.The multi-population approach is used to locate multiple local optima which are useful to find the global optimal solution quickly to dynamic multimodal problems.The diffusion model is used to increase the diversity in a guided fashion,which makes the neighbor individuals of previous optimal solutions move gradually from the previous optimal solutions and enlarge the search space.This approach uses both the information of current population and the part history information of the optimal solutions.Finally experimental studies on the moving peaks benchmark are carried out to evaluate the proposed algorithm and compare the performance of MDUMDA and multi-population quantum swarm optimization(MQSO) from the literature.The experimental results show that the MDUMDA is effective for the function with moving optimum and can adapt to the dynamic environments rapidly. 展开更多
关键词 univariate marginal distribution algorithm(UMDA) dynamic multimodal problems dynamic optimization multipopulation scheme.
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Clinical and pathological characteristics and prognosis of 132 cases of rectal neuroendocrine tumors 被引量:3
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作者 Yong-Jun Yu Yu-Wei Li +3 位作者 Yang Shi Zhao Zhang Min-Ying Zheng Shi-Wu Zhang 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2020年第8期893-902,共10页
BACKGROUND Neuroendocrine tumors(NETs)frequently occur in the gastrointestinal tract,lung,and pancreas,and the rectum and appendix are the sites with the highest incidence.Epidemiology statistics show that an estimate... BACKGROUND Neuroendocrine tumors(NETs)frequently occur in the gastrointestinal tract,lung,and pancreas,and the rectum and appendix are the sites with the highest incidence.Epidemiology statistics show that an estimated 8000 people every year in the United States are diagnosed with NETs occurring in the gastrointestinal tract,including the stomach,intestine,appendix,colon,and rectum.The pathological changes and clinical symptoms of NETs are not specific,and therefore they are frequently misdiagnosed.AIM To investigate the clinical symptoms,pathological characteristics,treatment,and prognosis of rectal neuroendocrine tumors(RNETs)by analyzing the clinical and pathological data of 132 RNET cases at our hospital.METHODS All RNETs were graded according to Ki-67 positivity and mitotic events.The tumors were staged as clinical stages I,II,III,and IV according to infiltrative depth and tumor size.COX proportional hazard model was used to assess the main risk factors for survival.RESULTS These 132 RNETs included 83 cases of G1,21 cases of G2,and 28 cases of G3(neuroendocrine carcinoma)disease.Immunohistochemical staining showed that 89.4%of RNETs were positive for synaptophysin and 39.4%positive for chromogranin A.There were 19,85,23,and 5 cases of clinical stages I,II,III,and IV,respectively.The median patient age was 52.96 years.The diameter of tumor,depth of invasion,and pathological grade were the main reference factors for the treatment of RNETs.The survival rates at 6,12,36,and 60 mo after operation were 98.5%,94.6%,90.2%,and 85.6%,respectively.Gender,tumor size,tumor grade,lymph node or distant organ metastasis,and radical resection were the main factors associated with prognosis of RNETs.Multivariate analysis showed that tumor size and grade were independent prognostic factors.CONCLUSION The clinical symptoms of RNETs are not specific,and they are easy to misdiagnose.Surgery is the main treatment method.The grade and stage of RNETs are the main indices to evaluate prognosis. 展开更多
关键词 Neuroendocrine tumors PROGNOSIS Univariate analysis Tumor size Tumor grade Neuroendocrine carcinoma
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Computation of the Rational Representation for Solutions of High-dimensional Systems 被引量:3
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作者 TAN CHANG ZHANG SHU-GONG 《Communications in Mathematical Research》 CSCD 2010年第2期119-130,共12页
This paper deals with the representation of the solutions of a polynomial system, and concentrates on the high-dimensional case. Based on the rational univari- ate representation of zero-dimensional polynomial systems... This paper deals with the representation of the solutions of a polynomial system, and concentrates on the high-dimensional case. Based on the rational univari- ate representation of zero-dimensional polynomial systems, we give a new description called rational representation for the solutions of a high-dimensional polynomial sys- tem and propose an algorithm for computing it. By this way all the solutions of any high-dimensional polynomial system can be represented by a set of so-called rational- representation sets. 展开更多
关键词 rational univariate representation high-dimensional ideal maximally independent set rational representation irreducible component
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Applications of Normality Test in Statistical Analysis 被引量:6
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作者 Nasrin Khatun 《Open Journal of Statistics》 2021年第1期113-122,共10页
In this study, to power comparison test, different univariate normality testing procedures are compared by using new algorithm. Different univariate and multivariate test are also analyzed here. And also review effici... In this study, to power comparison test, different univariate normality testing procedures are compared by using new algorithm. Different univariate and multivariate test are also analyzed here. And also review efficient algorithm for calculating the size corrected power of the test which can be used to compare the efficiency of the test. Also to test the randomness of generated random numbers. For this purpose, 1000 data sets with combinations of sample size n = 10, 20, 25, 30, 40, 50, 100, 200, 300 were generated from uniform distribution and tested by using different tests for randomness. The assessment of normality using statistical tests is sensitive to the sample size. Observed that with the increase of n, overall powers are increased but Shapiro Wilk (SW) test, Shapiro Francia (SF) test and Andeson Darling (AD) test are the most powerful test among other tests. Cramer-Von-Mises (CVM) test performs better than Pearson chi-square, Lilliefors test has better power than Jarque Bera (JB) Test. Jarque Bera (JB) Test is less powerful test among other tests. 展开更多
关键词 Normality Test Univariate Test Multivariate Test
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Statistical approach to determination of overhaul and maintenance cost of loading equipment in surface mining 被引量:8
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作者 Lashgari Ali Sayadi Ahmad Reza 《International Journal of Mining Science and Technology》 SCIE EI 2013年第3期441-446,共6页
The purpose of this research was to develop a new approach in determination of overhaul and maintenance cost of loading equipment in surface mining. Two statistical models including univariate exponential regression (... The purpose of this research was to develop a new approach in determination of overhaul and maintenance cost of loading equipment in surface mining. Two statistical models including univariate exponential regression (UER) and multivariate linear regression (MLR) were used in this study. Loading equipment parameters such as bucket capacity, machine weight, engine power, boom length, digging depth, and dumping height were considered as variables. The results obtained by models and mean absolute error rate indicate that these models can be applied as the useful tool in determination of overhaul and maintenance cost of loading equipment. The results of this study can be used by the decision-makers for the specific surface mining operations. 展开更多
关键词 Overhaul and maintenance cost Loading equipment Surface mining Univariate exponential regression Multivariate linear regression Principal component analysis
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Effects of microtopography on spatial point pattern of forest stands on the semi-arid Loess Plateau,China 被引量:5
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作者 WeiJun ZHAO Yan ZHANG +6 位作者 QingKe ZHU Wei QIN ShuZhen PENG Ping LI YanMin ZHAO Huan MA Yu WANG 《Journal of Arid Land》 SCIE CSCD 2015年第3期370-380,共11页
Microtopography may affect the distribution of forests through its effect on rain redistribution and soil water distribution on the semi-arid Loess Plateau,China.In this study,we investigated the characteristics of mi... Microtopography may affect the distribution of forests through its effect on rain redistribution and soil water distribution on the semi-arid Loess Plateau,China.In this study,we investigated the characteristics of microtopography on two shady slopes(slope A,5 hm2,uniform slope;slope B,5 hm2,microtopography slope) and surveyed the height,the diameter at breast height and the location(x,y coordinates) of all selected individual trees(Robinia pseudoacacia Linn.,Pyrus betulifolia Bunge,Populus hopeiensis Hu & Chow,Armeniaca sibirica Lam.,Populus simonii Carr.and Ulmus pumila Linn.) on slope A and slope B in the watersheds of Wuqi county,Shaanxi province.Subsequently,the effects of microtopography on the spatial pattern of forest stands were analyzed using Ripley's K(r) function.The results showed that:(1) The maximal aggregation radiuses of the tree species on the uniform slope(slope A) were larger than 40 m,whereas those of the tree species on the microtopography slope(slope B) were smaller than 30 m.(2) On slope B,the spatial association of R.pseudoacacia with P.betulifolia,A.sibirica,P.simonii and U.pumila varied from being strongly negative to positive at microtopography scales.The spatial association of Populus hopeiensis Hu & Chow with U.pumila also varied from being strongly negative to positive at microtopography scales.However,there was no spatial association between P.betulifolia and P.hopeiensis,P.betulifolia and A.sibirica,P.betulifolia and P.simonii,P.betulifolia and U.pumila,P.hopeiensis and A.sibirica,P.hopeiensis and P.simonii,A.sibirica and P.simonii,A.sibirica and U.pumila,and P.simonii and U.pumila.On slope A,the spatial association between tree species were strongly negative.The results suggest that microtopography may shape tree distribution patterns on the semi-arid Loess Plateau. 展开更多
关键词 microtopography univariate spatial patterns aggregation negative association positive association
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A data selection method for matrix effects and uncertainty reduction for laser-induced breakdown spectroscopy 被引量:1
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作者 龙杰 宋惟然 +1 位作者 侯宗余 王哲 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第7期82-89,共8页
Severe matrix effects and high signal uncertainty are two key bottlenecks for the quantitative performance and wide applications of laser-induced breakdown spectroscopy(LIBS).Based on the understanding that the superp... Severe matrix effects and high signal uncertainty are two key bottlenecks for the quantitative performance and wide applications of laser-induced breakdown spectroscopy(LIBS).Based on the understanding that the superposition of both matrix effects and signal uncertainty directly affects plasma parameters and further influences spectral intensity and LIBS quantification performance,a data selection method based on plasma temperature matching(DSPTM)was proposed to reduce both matrix effects and signal uncertainty.By selecting spectra with smaller plasma temperature differences for all samples,the proposed method was able to build up the quantification model to rely more on spectra with smaller matrix effects and signal uncertainty,therefore improving final quantification performance.When applied to quantitative analysis of the zinc content in brass alloys,it was found that both accuracy and precision were improved using either a univariate model or multiple linear regression(MLR).More specifically,for the univariate model,the root-mean-square error of prediction(RMSEP),the determination coefficients(R^(2))and relative standard derivation(RSD)were improved from 3.30%,0.864 and 18.8%to 1.06%,0.986 and 13.5%,respectively;while for MLR,RMSEP,R^(2)and RSD were improved from 3.22%,0.871 and 26.2%to 1.07%,0.986 and 17.4%,respectively.These results prove that DSPTM can be used as an effective method to reduce matrix effects and improve repeatability by selecting reliable data. 展开更多
关键词 laser-induced breakdown spectroscopy(LIBS) quantification UNCERTAINTY univariate/multivariate analysis matrix effects temperature matching
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Surgical Treatment of Liver Metastases from Gastric Cancer 被引量:2
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作者 Daniel Vasilev Kostov Georgi Leonidov Kobakov Daniel Veselov Yankov 《Surgical Science》 2013年第9期393-400,共8页
Background: Hepatectomy for gastric metastases remains controversial. We aimed at assessing the surgical results, clinicopathological features of gastric cancer liver metastases (GCLM) and prognostic factors. Methods:... Background: Hepatectomy for gastric metastases remains controversial. We aimed at assessing the surgical results, clinicopathological features of gastric cancer liver metastases (GCLM) and prognostic factors. Methods: The outcome of 28 consecutive patients with synchronous (n = 24) or metachronous (n = 4) GCLM was retrospectively analyzed. Curatively, initial hepatectomies such as segmentectomy and hemihepatectomy or non-anatomical limited liver resection less extensive than segmentectomy followed complete primary gastric cancer (GC) resections. Results: Median survival time was 16 months (range, 5 - 66 months). The actuarial overall 12-, 36-, and 60-month survival rates after hepatectomy were 67.8% (n = 19), 39.2% (n = 11), and 28.5% (n = 8), respectively. In multivariate analysis, absent GC serosal invasion-hazard ratio (HR) 1;95% confidence interval (CI) 1.2 - 9.9;P = 0.020;solitary LM-HR 1;95% CI 1.6 - 16.0;P = 0.005, and?curative liver resection with negative resection margin (R0)-HR 1, 95% CI 2.2 - 18.0;P = 0.001 were independent prognostic factors. Conclusions: Surgery of GCLM is a good indication in well-selected patients with an absent serosal invasion of primary tumour, single GCLM and attainment of R0 liver resection. For most GCLM patients, however, there are no other therapeutic modalities. Thus systemic chemotherapy remains the best hope for a longer patient’s survival and an improved individual quality of life. 展开更多
关键词 GASTRIC Cancer Liver METASTASES HEPATECTOMY Survival PROGNOSTIC Factors Univariate ANALYSIS MULTIVARIATE ANALYSIS
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Sexual Dimorphism of the Jilin Clawed Salamander,Onychodactylus zhangyapingi,(Urodela:Hynobiidae:Onychodactylinae) from Jilin Province,China 被引量:2
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作者 Jianli XIONG Xiuying LIU +2 位作者 Xiaomei ZHANG Mengyun LI Yao MIN 《Asian Herpetological Research》 SCIE CSCD 2016年第3期220-226,共7页
Sexual dimorphism in size and shape is common in many organisms, and is a key evolutionary feature. In this study, we analyzed morphometric data of the Jilin clawed salamander Onychodactylus zhangyapingi, an endemic C... Sexual dimorphism in size and shape is common in many organisms, and is a key evolutionary feature. In this study, we analyzed morphometric data of the Jilin clawed salamander Onychodactylus zhangyapingi, an endemic Chinese salamander, to examine sexual size and shape dimorphism. The morphometric data included 14 characteristics of 13 females and 11 males and was analyzed using univariate and multivariate methods. Our results showed that sexual dimorphism occurs not only in body size, but also in body shape. Males have a longer snout-vent length than females, a rarely reported pattern of male-biased sexual size dimorphism. Females have a larger space between the axilla and groin than males, while males have longer and larger tails compared to females. The sexual dimorphism in body size and shape can be explained by existing theories, but there is little data for the mating system, behavior, reproduction, or ecology of O. zhangyapingi, so further studies are required. 展开更多
关键词 sexual mating evolutionary Jilin endemic reproduction longer univariate multivariate explained
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Diversity, composition and host-species relationships of epiphytic orchids and ferns in two forests in Nepal 被引量:2
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作者 Yagya P. ADHIKARI Anton FISCHER +3 位作者 Hagen S.FISCHER Maan B.ROKAYA Prakash BHATTARAI Axel GRUPPE 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1065-1075,共11页
Epiphytic plant species are an important part of biological diversity. It is therefore essential to understand the distribution pattern and the factors influencing such patterns. The present study is aimed at observin... Epiphytic plant species are an important part of biological diversity. It is therefore essential to understand the distribution pattern and the factors influencing such patterns. The present study is aimed at observing the patterns of species richness, abundances and species composition of epiphytic orchids and ferns in two subtropical forests in Nepal. We also studied the relationship of host plants(Schima wallichii and Quercus lanata) and epiphyte species. Data were collected in Naudhara community forest(CF) and the national forest(NF) in Shivapuri Nagarjun National Park. The data were analyzed using univariate and multivariate tests. In total, we recorded 41 species of epiphytes(33 orchid and 8 fern species). Orchid species abundance is significantlyhigher in CF compared to NF. Orchid species richness and abundance increased with increasing southern aspect whereas it decreased with increasing canopy cover, and fern species richness increased with host bark roughness. Orchid abundance was positively correlated with increasing bark p H, stem size, tree age and tree height and negatively correlated with increasing steepness of the area. Likewise, fern abundances were high in places with high canopy cover, trees that were tall and big, but decreased with increasing altitude and southern aspect. The composition of the orchid and fern species was affected by altitude, aspect, canopy cover, DBH, number of forks and forest management types. We showed that the diversity of orchid and fern epiphytes is influenced by host characteristics as well as host types. The most important pre-requisite for a high epiphyte biodiversity is the presence of oldrespectively tall trees, independent of the recent protection status. This means:(i) for protection, e.g.in the frame of the national park declaration, such areas should be used which host such old tall trees;and(ii) also in managed forests and even in intensively used landscapes epiphytes can be protected by letting a certain number of trees be and by giving them space to grow old and tall. 展开更多
关键词 Environmental factors Epiphytes Large trees Indicator species Multivariate and univariate analyses Permutations tests
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Modelling of Indian Monsoon Rainfall Series by Univariate Box-Jenkins Type of Models 被引量:1
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作者 S.D.Dahale S.V.Singh 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第2期211-220,共10页
The time domain approach, i.e. Autoregressive (AR) processes, of time series analysis is applied to the monsoon rainfall series of India and its two major regions, viz. North-West India and Central India. Since the or... The time domain approach, i.e. Autoregressive (AR) processes, of time series analysis is applied to the monsoon rainfall series of India and its two major regions, viz. North-West India and Central India. Since the original time series shows no modelable structure due to the presence of high interannual variability, a 3-point running filter is applied before exploring and fitting appropriate stochastic models. Out of several parsimonious models fitted, AR(3) is found to be most suitable. The usefulness of this fitted model is validted on an independent datum of 18 years and some skill has been noted. These models therefore can be used for low skill higher lead time forecasts of monsoon. Further the forecasts produced through such models can be combined with other forecasts to increase the skill of monsoon forecasts. 展开更多
关键词 Modelling of Indian Monsoon Rainfall Series by Univariate Box-Jenkins Type of Models
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