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Red cell distribution width/platelet ratio estimates the 3-year risk of decompensation in Metabolic Dysfunction-Associated Steatotic Liver Disease-induced cirrhosis
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作者 Marcello Dallio Mario Romeo +8 位作者 Paolo Vaia Salvatore Auletta Simone Mammone Marina Cipullo Luigi Sapio Angela Ragone Marco Niosi Silvio Naviglio Alessandro Federico 《World Journal of Gastroenterology》 SCIE CAS 2024年第7期685-704,共20页
BACKGROUND For compensated advanced chronic liver disease(cACLD)patients,the first decompensation represents a dramatically worsening prognostic event.Based on the first decompensation event(DE),the transition to deco... BACKGROUND For compensated advanced chronic liver disease(cACLD)patients,the first decompensation represents a dramatically worsening prognostic event.Based on the first decompensation event(DE),the transition to decompensated advanced chronic liver disease(dACLD)can occur through two modalities referred to as acute decompensation(AD)and non-AD(NAD),respectively.Clinically Significant Portal Hypertension(CSPH)is considered the strongest predictor of decompensation in these patients.However,due to its invasiveness and costs,CSPH is almost never evaluated in clinical practice.Therefore,recognizing noninvasively predicting tools still have more appeal across healthcare systems.The red cell distribution width to platelet ratio(RPR)has been reported to be an indicator of hepatic fibrosis in Metabolic Dysfunction-Associated Steatotic Liver Disease(MASLD).However,its predictive role for the decompensation has never been explored.AIM In this observational study,we investigated the clinical usage of RPR in predicting DEs in MASLD-related cACLD patients.METHODS Fourty controls and 150 MASLD-cACLD patients were consecutively enrolled and followed up(FUP)semiannually for 3 years.At baseline,biochemical,clinical,and Liver Stiffness Measurement(LSM),Child-Pugh(CP),Model for End-Stage Liver Disease(MELD),aspartate aminotransferase/platelet count ratio index(APRI),Fibrosis-4(FIB-4),Albumin-Bilirubin(ALBI),ALBI-FIB-4,and RPR were collected.During FUP,DEs(timing and modaities)were recorded.CSPH was assessed at the baseline and on DE occurrence according to the available Clinical Practice Guidelines.RESULTS Of 150 MASLD-related cACLD patients,43(28.6%)progressed to dACLD at a median time of 28.9 months(29 NAD and 14 AD).Baseline RPR values were significantly higher in cACLD in comparison to controls,as well as MELD,CP,APRI,FIB-4,ALBI,ALBI-FIB-4,and LSM in dACLD-progressing compared to cACLD individuals[all P<0.0001,except for FIB-4(P:0.007)and ALBI(P:0.011)].Receiving operator curve analysis revealed RPR>0.472 and>0.894 as the best cut-offs in the prediction respectively of 3-year first DE,as well as its superiority compared to the other non-invasive tools examined.RPR(P:0.02)and the presence of baseline-CSPH(P:0.04)were significantly and independently associated with the DE.Patients presenting baseline-CSPH and RPR>0.472 showed higher risk of decompensation(P:0.0023).CONCLUSION Altogether these findings suggest the RPR as a valid and potentially applicable non-invasive tool in the prediction of timing and modalities of decompensation in MASLD-related cACLD patients. 展开更多
关键词 Liver cirrhosis Red blood cell distribution width Red blood cell distribution width to platelet ratio Translational Medicine Prognostic biomarker
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Using Pearson’s System of Curves to Approximate the Distributions of the Difference between Two Correlated Estimates of Signal-to-Noise Ratios: The Cases of Bivariate Normal and Bivariate Lognormal Distributions
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作者 Mohamed M. Shoukri 《Open Journal of Statistics》 2024年第3期207-227,共21页
Background: The signal-to-noise ratio (SNR) is recognized as an index of measurements reproducibility. We derive the maximum likelihood estimators of SNR and discuss confidence interval construction on the difference ... Background: The signal-to-noise ratio (SNR) is recognized as an index of measurements reproducibility. We derive the maximum likelihood estimators of SNR and discuss confidence interval construction on the difference between two correlated SNRs when the readings are from bivariate normal and bivariate lognormal distribution. We use the Pearsons system of curves to approximate the difference between the two estimates and use the bootstrap methods to validate the approximate distributions of the statistic of interest. Methods: The paper uses the delta method to find the first four central moments, and hence the skewness and kurtosis which are important in the determination of the parameters of the Pearsons distribution. Results: The approach is illustrated in two examples;one from veterinary microbiology and food safety data and the other on data from clinical medicine. We derived the four central moments of the target statistics, together with the bootstrap method to evaluate the parameters of Pearsons distribution. The fitted Pearsons curves of Types I and II were recommended based on the available data. The R-codes are also provided to be readily used by the readers. 展开更多
关键词 Signal-to-Noise ratio Bivariate Distributions Bootstrap Methods Delta Method Pearson System of Curves
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Challenges of Vietnamese Agricultural Cooperatives in the 21st Century:The Link Between Efficiency and Legality
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作者 Trịnh Minh Trạch 《Economics World》 2024年第1期42-53,共12页
The article shows that the situation of agricultural cooperatives in the world in general and agricultural cooperatives in Vietnam in particular are facing certain challenges in the context of globalization in the 21s... The article shows that the situation of agricultural cooperatives in the world in general and agricultural cooperatives in Vietnam in particular are facing certain challenges in the context of globalization in the 21st century.The article points out limitations on:the nature,principles of democratic member control and principles of surplus distribution of the International Cooperative Alliance,as well as Vietnamese law in cooperative management. 展开更多
关键词 agricultural cooperative democratic principles principles of surplus distribution cooperative law
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The Value of MLPR,NLR,and RDW in the Assessment of Combined Pulmonary Embolism in Elderly Patients with AECOPD
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作者 Ya Zhang Jianye Yang 《Journal of Clinical and Nursing Research》 2024年第7期255-260,共6页
Objective:To investigate the diagnostic value of the monocyte-to-large-platelet ratio(MLPR),neutrophil-to-lymphocyte ratio(NLR),and red blood cell distribution width(RDW)for pulmonary embolism(PE)in patients with acut... Objective:To investigate the diagnostic value of the monocyte-to-large-platelet ratio(MLPR),neutrophil-to-lymphocyte ratio(NLR),and red blood cell distribution width(RDW)for pulmonary embolism(PE)in patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Methods:A total of 60 elderly AECOPD patients were enrolled and divided into embolus group(12 cases)and thrombus group(48 cases)according to whether they were combined with pulmonary embolism and the MLPR,NLR,and RDW values of the two groups were determined respectively.Results:The patients in the two groups had different degrees of vascular structural and functional abnormalities,and the MLPR,NLR,and RDW in the embolus group were significantly higher than those in the thrombus group(P<0.05);while the differences in NLR and RDW between the two groups were not significant.Conclusion:MLPR,NLR,and RDW can provide an objective basis for assessing PE in elderly AECOPD patients. 展开更多
关键词 Monocyte-to-large-platelet ratio(MLPR) Neutrophil-to-lymphocyte ratio(NLR) Red blood cell distribution width(RDW) Acute exacerbation of chronic obstructive pulmonary disease(AECOPD) Pulmonary embolism
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Application of neutrophil-lymphocyte ratio and red blood cell distribution width in diabetes mellitus complicated with heart failure
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作者 Jie Pang Lin-Yan Qian +1 位作者 Ping Lv Xiao-Ru Che 《World Journal of Diabetes》 SCIE 2024年第6期1226-1233,共8页
BACKGROUND Accumulating clinical evidence has shown that diabetes mellitus(DM)is a serious risk factor for cardiovascular disorders and an important factor for adverse cardiovascular events.AIM To explore the value of... BACKGROUND Accumulating clinical evidence has shown that diabetes mellitus(DM)is a serious risk factor for cardiovascular disorders and an important factor for adverse cardiovascular events.AIM To explore the value of the combined determination of the neutrophil-lymphocyte ratio(NLR)and red blood cell distribution width(RDW)in the early diagnosis and prognosis evaluation of DM complicated with heart failure(HF).METHODS We retrospectively analyzed clinical data on 65 patients with type 2 DM(T2DM)complicated with HF(research group,Res)and 60 concurrent patients with uncomplicated T2DM(control group,Con)diagnosed at Zhejiang Provincial People’s Hospital between January 2019 and December 2021.The NLR and RDW values were determined and comparatively analyzed,and their levels in T2DM+HF patients with different cardiac function grades were recorded.The receiver operating characteristic(ROC)curves were plotted to determine the NLR and RDW values(alone and in combination)for the early diagnosis of HF.The correlation between NLR and RDW with the presence or absence of cardiac events was also investigated.RESULTS Higher NLR and RDW levels were identified in the Res vs the Con groups(P<0.05).The NLR and RDW increased gradually and synchronously with the deterioration of cardiac function in the Res group,with marked differences in their levels among patients with grade II,III,and IV HF(P<0.05).ROC curve analysis revealed that NLR combined with RDW detection had an area under the curve of 0.915,a sensitivity of 76.9%,and a specificity of 100%for the early diagnosis of HF.Furthermore,HF patients with cardiac events showed higher NLR and RDW values compared with HF patients without cardiac events.CONCLUSION NLR and RDW were useful laboratory indicators for the early diagnosis of DM complicated with HF,and their joint detection was beneficial for improving diagnostic efficiency.Additionally,NLR and RDW values were directly proportional to patient outcomes. 展开更多
关键词 Neutrophil-lymphocyte ratio Red blood cell distribution width Type 2 diabetes Heart failure Early diagnosis
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Probability Distribution of Ratio of China Aviation Network Edge Vertices Degree and Its Evolutionary Trace Based on Complex Network
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作者 Cheng Xiangjun Yang Fang Wei Liying 《Journal of Traffic and Transportation Engineering》 2024年第3期119-129,共11页
In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of ratio of China aviation network edge vertices degree were s... In order to reveal the complex network characteristics and evolution principle of China aviation network, the probability distribution and evolution trace of ratio of China aviation network edge vertices degree were studied based on the statistics data of China civil aviation network in 1988, 1994, 2001, 2008 and 2015. According to the theory and method of complex network, the network system was constructed with the city where the airport was located as the network node and the route between cities as the edge of the network. Based on the statistical data, the ratio of edge vertices degree in China aviation network in 1988, 1994, 2001, 2008 and 2015 were calculated. Using the probability statistical analysis method and regression analysis approach, it was found that the ratio of edge vertices degree had linear probability distribution and the two parameters of the probability distribution had linear evolution trace. 展开更多
关键词 Complex network China aviation network ratio of edge vertices degree linear probability distribution linear evolution trace.
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Therapeutic Effect of Daphnetin on Mastitis Induced by Staphylococcus aureus in Mice
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作者 Yi LI Qianjiong HUANG +3 位作者 Jinhui JIANG Guoyang LIN Chenchen HUANG Jie GAO 《Medicinal Plant》 2023年第6期60-63,共4页
[Objectives]To observe the effects of daphnetin on mastitis induced by Staphylococcus aureus in mice.[Methods]18 postpartum ICR female mice were used to establish mastitis animal model,and were randomly divided into t... [Objectives]To observe the effects of daphnetin on mastitis induced by Staphylococcus aureus in mice.[Methods]18 postpartum ICR female mice were used to establish mastitis animal model,and were randomly divided into three groups(A,B,and C)with 6 mice in each group.Group A:blank control group;group B:S.Aureus model group;group C:S.Aureus model+daphnetin group.The experimental groups were injected 1 mL of 1.0×104 CFU/100μL of S.aureus of along the nipple catheter.The suspension was placed in the 3 rd and 4 th pairs of mammary glands,and the control group was injected with the same dose of normal saline.On the second day after infection,the rats in group A,B and C were given drugs by gavage,while the rats in group A and B were given normal saline and the rats in group C were given daphnetin once a day for 6 consecutive days.Blood samples were collected from living eyeballs,and blood cells were analyzed by automatic flow cytometer after anticoagulation.[Results]The NLR and Systemie Immune Inflammati-on Index(SII)in the blood of mastitis mice induced by S.aureus were significantly higher than those in the control group(P<0.01),suggesting that neutrophil to lymphocyte ratio(NLR)and SII can be used as diagnostic indicators of mastitis,and the levels of NLR and SII decreased significantly after daphnetin intervention.[Conclusions]NLR and SII showed high levels in mastitis mice,which are valuable for the diagnosis of mastitis and the evaluation of its prognosis.After the intervention of daphnetin,both of them decreased significantly,indicating that daphnetin has a good prognosis trend in mastitis mice induced by S.aureus. 展开更多
关键词 DAPHNETIN MASTITIS Staphylococcus aureus Red cell distribution width(RDW) Neutrophil to lymphocyte ratio(NLR) ratio of platelets to lymph-ocytes(PLR) Systemie Immune Inflammati-on Index(SII)
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Migration and population structure characteristics of the small yellow croaker Larimichthys polyactis in the southern Yellow Sea 被引量:8
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作者 XIONG Ying ZHONG Xiaming +1 位作者 TANG Jianhua YANG Jian 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第6期34-41,共8页
Monthly fishery survey data of the small yellow croaker Larimichthys polyactis in the southern Yellow Sea from2003 and 2013 were employed to evaluate the variation in the resource distribution and biological character... Monthly fishery survey data of the small yellow croaker Larimichthys polyactis in the southern Yellow Sea from2003 and 2013 were employed to evaluate the variation in the resource distribution and biological characteristics(especially body length and sex ratio) in the population on a decadal scale.The results indicated that the small yellow croaker migrated from the Shawai fishing ground to the Dasha fishing ground in spring and was mainly distributed in the central and western parts of the Dasha fishing ground in April and May.Larimichthys polyactis in the Dasha fishing ground migrated eastward to offshore wintering grounds in autumn and reached the central Dasha fishing ground in October and November.The small yellow croaker entered the western waters of the Shawai fishing ground in winter.A large number of age 0+ fish occurred in the Shawai and Jiangwai fishing grounds in October of 2003 and 2013.The body lengths of the spawning stock and wintering stock in 2013 were larger than those in 2003,and the monthly sex ratios(female to male) were significantly less than 1 in both years.The monthly distribution of this fish in the southern Yellow Sea was consistent with a previous finding that "the stock migrated between the wintering grounds in the west of Jeju Island and the Lüsi spawning grounds" but tended to move more northward,with the spawning grounds extending outward.In the past decade,body length variation experienced a decline after an increase,rather than a steady decrease.The sex ratio in the single-stick stow net showed a tendency to increase over the decade,but was either less than or more than 1 depending on the fishing gear;therefore,further studies should be conducted to determine the sex structure. 展开更多
关键词 small yellow croaker resource distribution MIGratioN body length sex ratio
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NONNULL DISTRIBUTION OF THE LIKELIHOOD RATIO CRITERION FOR TESTING THE EQUALITY OF DIAGONAL BLOCKS WITH BLOCKWISE INDEPENDENCE 被引量:5
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作者 A. K. Gupta C. C. Chao(Bowling Green State University Bowling Green, OH 43403-0221 C. C. ChaoJacksonville State Univesity Jacksonville, AL 36265) 《Acta Mathematica Scientia》 SCIE CSCD 1994年第2期195-203,共9页
In this paper, the nonnull moments and the distributions of the likelihood ratio criterion for testing the equality of diagonal blocks with blockwise independence under certain alternatives have derived.
关键词 ratio BLOCKWISE CRITERION DIAGONAL DISTRIBUTION EQUALITY FOR INDEPENDENCE LIKELIHOOD NONNULL
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R/S ratio in lead Ⅱ, and the prognostic significance of red cell distribution width in acute coronary syndrome 被引量:1
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作者 Abuzer Coskun Sevki Hakan Eren 《World Journal of Clinical Cases》 SCIE 2019年第16期2217-2226,共10页
BACKGROUND In spite of developing medical technologies to discover the etiopathogenesis of diseases and developments in the treatment of coronary artery disease, acute coronary syndromes(ACS) continue to be the main c... BACKGROUND In spite of developing medical technologies to discover the etiopathogenesis of diseases and developments in the treatment of coronary artery disease, acute coronary syndromes(ACS) continue to be the main cause of mortality and morbidity worldwide. New cardiac biomarkers and techniques are needed to help provide rapid diagnosis in order to evaluate risk in coronary artery patients.AIM To evaluate the effects of R to S ratio(RSR) in the electrocardiograph of patients with ACS, from the point of the arising complication after myocardial infarction(MI), to three-vessel disease(TVD) and mortality.METHODS The data of 1,296 patients with ACS, who presented to the emergency department of our hospital with chest pain between January 2014 and December2018 and were admitted to the cardiology clinic, were retrospectively included in this cross-sectional cohort study. Patients with an RSR value less than I were assigned to group Ⅰ, while those with an RSR value greater than Ⅰ were assigned to group Ⅱ.RESULTS In our study, 466(35.9%) of the 1,296 patients, 357(38.3%) in group 1 and 109(29.9%) in group 2, were female, with a mean age of 61.56 ± 9.42. ST-elevation MI 573(44.2%), unstable angina(UA) 502(38.7%) and non ST-elevation MI 220(17%)were more prevalent in group Ⅰ. Acute anterior MI 263(20.3) in group Ⅰ, and acute inferior MI 184(14.2) in group Ⅱ was higher. Ischemic heart failure was the most common complication. In group Ⅱ, the red cell distribution width(RDW) was 15.42 ± 1.82, the gensini score was 48.39 ± 36.44, the left ventricular ejection fraction was 41.17 ± 10.41, the TVD was 111(8.5), and the mortality rate was 72(5.6), which was significantly higher than group Ⅰ RDW; in MI with ST and nonST-elevation, in TVD, mortality and complications were high and low in UA. In single and multivariate regression analyses, the variables were associated with ACS risk.CONCLUSION RSR levels may be an auxiliary predictive value in ACS in terms of complications developing after MI, TVD, and mortality. 展开更多
关键词 Acute CORONARY SYNDROME EMERGENCY DEPARTMENT R/S ratio Red cell distribution WIDTH
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Influence of Pt/Ru anodic ratio on the valorization of ethanol by PEM electrocatalytic reforming towards value-added products 被引量:2
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作者 Alberto Rodriguez-Gomez Fernando Dorado +1 位作者 Antonio de Lucas-Consuegra Ana Raquel de la Osa 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期264-275,共12页
The ethanol electro-reforming process was studied over PtRu/C catalysts synthesized by the modified polyol method with different compositions.In particular,this work reports the influence of anodic Pt:Ru ratio(5:1,2:1... The ethanol electro-reforming process was studied over PtRu/C catalysts synthesized by the modified polyol method with different compositions.In particular,this work reports the influence of anodic Pt:Ru ratio(5:1,2:1 and 1:2)on the organic product distribution(acetaldehyde,acetic acid and ethyl acetate)and pure hydrogen generation at different current densities operation levels.Physicochemical characterization of the catalysts was made by X-ray diffraction(XRD),temperature-programmed reduction(TPR)and N_(2) adsorption-desorption measurements.XRD patterns showed that Ru is introduced into the Pt structure,forming an alloy between both metals.Also,the degree of alloy was higher by increasing the Ru amounts.From TPR profiles Pt was found to be properly reduced while Ru was both in metallic state and forming RuO2.The electrochemical behaviour of each catalyst towards ethanol electroreforming process was investigated through electrochemical techniques in a half cell and a single proton exchange membrane(PEM)cell systems.An intermediate Pt:Ru ratio was found to result in high current density and electrochemical surface area(ECSA)values along with lower amounts of adsorbed species.Also,Ru addition seems to diminish the degree of degradation of the catalyst.Based on characterization and in agreement with essays carried out in a PEM cell at mild conditions(80℃ and 1 atm),PtRu/C 2:1 anode provided the best electrocatalytic results in terms of current density(740 mA cm^(-2)),hydrogen production and selectivity toward acetic acid(up to 15%apart from acetaldehyde and ethyl acetate)while requiring the lowest energy consumption. 展开更多
关键词 Ethanol electro-reforming PEM cell Pt:Ru anodic ratio Hydrogen production Value-added liquid product distribution
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The Effect of Clay Content and Land Use on Dispersion Ratio at Different Locations in Sulaimani Governorate—Kurdistan Region—Iraq 被引量:1
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作者 Saman M. K. Rasheed 《Open Journal of Soil Science》 2016年第1期1-8,共8页
Land use changes from natural ecosystems into managed ecosystems resulted in negative impact on soil structure and quality. The purpose of this study was to determine the influences of different land-use types on phys... Land use changes from natural ecosystems into managed ecosystems resulted in negative impact on soil structure and quality. The purpose of this study was to determine the influences of different land-use types on physical and chemical properties of soils in Sulaimani governorate. Land use systems including natural forest, pastureland and agriculture were identified. Ten of soil samples were collected from the 0 - 30 cm depth, and some soil physical and chemical properties of soil were determined. The land use alters from forest to agriculture resulting in significant decrease in organic matter, calcium carbonate and soil surface area and with this change, dispersion ratio affected on the physical property. The value of DR was highest in the Zrguezi Gawra cultivated with Cucumber and the lowest value in Dukan is 13%, and correlation coefficient between dispersion DR with sand, silt and bulk density is positive, value is (0.4979, 0.0126 and 0.7536) respectively, and with clay and specific surface area (SSA) the correlation coefficient value is (-0.7281 and -0.4466). 展开更多
关键词 Particle Size Distribution Dispersion ratio Bulk Density Organic Matter
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THE ASYMPTOTIC DISTRIBUTIONS OF EMPIRICAL LIKELIHOOD RATIO STATISTICS IN THE PRESENCE OF MEASUREMENT ERROR
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作者 伍长春 张润楚 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期232-242,共11页
Suppose that several different imperfect instruments and one perfect instrument are independently used to measure some characteristics of a population. Thus, measurements of two or more sets of samples with varying ac... Suppose that several different imperfect instruments and one perfect instrument are independently used to measure some characteristics of a population. Thus, measurements of two or more sets of samples with varying accuracies are obtained. Statistical inference should be based on the pooled samples. In this article, the authors also assumes that all the imperfect instruments are unbiased. They consider the problem of combining this information to make statistical tests for parameters more relevant. They define the empirical likelihood ratio functions and obtain their asymptotic distributions in the presence of measurement error. 展开更多
关键词 Empirical likelihood ratio statistics asymptotic distribution measurement error
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The Distribution of the Concentration Ratio for Samples from a Uniform Population
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作者 Giovanni Girone Antonella Nannavecchia 《Applied Mathematics》 2015年第1期57-70,共14页
In the present paper we derived, with direct method, the exact expressions for the sampling probability density function of the Gini concentration ratio for samples from a uniform population of size n = 6, 7, 8, 9 and... In the present paper we derived, with direct method, the exact expressions for the sampling probability density function of the Gini concentration ratio for samples from a uniform population of size n = 6, 7, 8, 9 and 10. Moreover, we found some regularities of such distributions valid for any sample size. 展开更多
关键词 GINI Concentration ratio UNIFORM DISTRIBUTION Order STATISTICS PROBABILITY Density Function
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Odds Ratio &Relative Risk Ratio of Buoy Conditions for Storms in the Atlantic Basin
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作者 Joy Marie D’Andrea Rebecca Dyanne Wooten Wendy Amanda Pogoda 《Open Journal of Statistics》 2018年第5期747-759,共13页
The purpose of this paper is to bring awareness to the general public that certain conditions that occur at a buoy in the Atlantic Basin, such as wind located at the buoy, pressure located at a buoy, water temperature... The purpose of this paper is to bring awareness to the general public that certain conditions that occur at a buoy in the Atlantic Basin, such as wind located at the buoy, pressure located at a buoy, water temperature located at a buoy, atmospheric pressure located at a buoy, may be useful in helping predict when a hurricane could possibly hit the state of Florida in the future. One of the goals of this paper is to bring new statistical methods to investigate and analyze data, which will create better predicable measures in determining when a hurricane will possibly hit the state of Florida. In this paper, the topics of binary logistic regression and multinomial regression modeling are discussed in reference to their outcomes of both the odds ratio and relative risk ratio respectively. The coefficients from these models will show which prospective buoy conditions are possibly more responsible for indication of a storm being present in the Atlantic Basin. In this paper, the data that was used and compiled into a larger data set came from two different sources. First, the hurricane data for the years 1992-2013 came from Unisys Weather site (Atlantic Basin Hurricanes data) and the buoy data has been available from the National Buoy Center. In this paper, the variables of interest are: storm present, buoy wind speed, buoy pressure, buoy atmospheric temperature, buoy water temperature and buoy wind direction. The buoy conditions are the buoy wind, the buoy wind direction, the buoy pressure, buoy atmospheric temperature and the buoy water temperature. 展开更多
关键词 Hurricanes PARAMETRIC Analysis STATISTICS Probability DISTRIBUTIONS Odds ratio
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The Natural Probability Distribution of Load and Unload Response Ratio
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作者 Chen Qifu,Yin Xiangchu,and Ma LiCenter for Analysis and Prediction,SSB,Beijing 100036,China 《Earthquake Research in China》 1997年第1期43-49,共7页
In this paper,the Gutenberg-Richter model is used to generate seismic events.The events that satisfy the random distribution are also generated.With those events,the natural probability distribution of Load and Unload... In this paper,the Gutenberg-Richter model is used to generate seismic events.The events that satisfy the random distribution are also generated.With those events,the natural probability distribution of Load and Unload Response Ratio(LURR),which measures quantitatively the degree of instability of a nonlinear system,is discussed.The study is based on stress energy release,which is chosen as the response of nonlinear system F3.The comparative results from the observation catalogue and generating data are also studied.It is revealed that the natural probability of LURR is mostly stable when the sample number is sufficient.The lower the natural probability of LURR,the more the precursory is information it may contain.The influence of Y3 resulting from the sample number and the magnitude range of events is also discussed. 展开更多
关键词 NATURAL PROBABILITY Distribution System EVENT load-unload RESPONSE ratio.
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On the Dynamics of a Stochastic Ratio-Dependent Predator-Prey System with Infection for the Prey 被引量:2
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作者 Jiying Ma Haimiao Ren 《Open Journal of Applied Sciences》 2021年第4期440-457,共18页
In this paper, we investigate the dynamics of a stochastic predator-prey model with ratio-dependent functional response and disease in the prey. Firstly, we prove the existence and uniqueness of the positive solution ... In this paper, we investigate the dynamics of a stochastic predator-prey model with ratio-dependent functional response and disease in the prey. Firstly, we prove the existence and uniqueness of the positive solution for the stochastic model by using conventional methods. Then we obtain the threshold <img alt="" src="Edit_0a62b9be-7934-457b-aca3-af3420f5b5ee.png" /> for the infected prey population, that is, the disease will tend to extinction if <img alt="" src="Edit_e6cd63f6-de07-42be-a22a-8750d6c8aac9.png" />< 1, and it will exist in the long time if  <img alt="" src="Edit_5964fdd8-a9fe-4dc2-b897-f4206f046f65.png" />> 1. Finally, the sufficient condition on the existence of a unique ergodic stationary distribution is obtained, which indicates that all the populations are permanent in the time mean sense. Numerical simulations are conducted to verify our analysis results. 展开更多
关键词 Stochastic Predator-Prey Model ratio-DEPENDENT Stationary Distribution EXTINCTION
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The Random Distribution of the Loading and Unloading Response Ratio Under the Assumptions of Poisson Models
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作者 Zhuang Jiancang and Yin XiangchuCentre for Analysis and Prediction,CSB,Beijing 100036,China Research Center of Exploration Geophysics,CSB,Zhengzhou 450002,China Laboratory of Nonlinear Mechanics, Institute of Mechanics,Chinese Academy of Sciences,Beijing 100080,China 《Earthquake Research in China》 2000年第1期42-52,共11页
This paper discussed the random distribution of the loading and unloading response ratio(LURR) of different definitions(Y<sub>1</sub>~Y<sub>5</sub>)using the assumptions that the earthquak... This paper discussed the random distribution of the loading and unloading response ratio(LURR) of different definitions(Y<sub>1</sub>~Y<sub>5</sub>)using the assumptions that the earthquakes occurfollowing the Poisson process and their magnitudes obey the Gutenberg-Richter law.Theresults show that Y<sub>1</sub>~Y<sub>5</sub> are quite stable or concentrated when the expected number of eventsin the calculation time window is relatively large(】40);but when this occurrence ratebecomes very small,Y<sub>2</sub>~Y<sub>5</sub> become quite variable or unstable.That is to say,a high value ofthe LURR can be produced not only from seismicity before a large earthquake,but also from arandom sequence of earthquakes that obeys a Poisson process when the expected number ofevents in the window is too small.To check the influence of randomness in the catalogue tothe LURR,the random distribution of the LURR under Poisson models has been calculated bysimulation.90%,95% and 99% confidence ranges of Y<sub>1</sub> and Y<sub>3</sub> are given in this paper,which is helpful to quantify the random 展开更多
关键词 Loading and UNLOADING response ratio POISSON Model Gutenberg-Richter LAW RANDOM distribution CONFIDENCE BAND
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基于NOMA-OFDM的雷达通信一体化波形设计
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作者 李风从 王子墨 +2 位作者 仝方遒 冯翔 赵宜楠 《现代雷达》 CSCD 北大核心 2024年第8期14-21,共8页
针对基于正交频分复用的雷达通信一体化波形设计中,通信信息的随机性会影响雷达性能以及过高峰均包络比(PAPR)可能导致信号在射频端出现严重失真的问题,文中提出了利用非正交多址将雷达信号与通信信号在功率域中分开,以降低通信信息随... 针对基于正交频分复用的雷达通信一体化波形设计中,通信信息的随机性会影响雷达性能以及过高峰均包络比(PAPR)可能导致信号在射频端出现严重失真的问题,文中提出了利用非正交多址将雷达信号与通信信号在功率域中分开,以降低通信信息随机性对雷达性能的影响,并利用主动星座图扩展(ACE)对叠加信号进行PAPR抑制的波形设计方法。首先,分析了传统功率分配原则导致叠加星座出现混叠的原因,并给出在不同调制阶数的最佳功率分配;其次,从理论上分析了ACE技术对叠加信号进行PAPR抑制的可行性;最后,仿真结果表明,在不同调制方式和不同信噪比下,当功率分配最佳时能同时达成雷达信号高检测率和通信符号最低误码率。ACE技术的使用同时保证了优良的雷达性能和通信端的低误码率,对叠加信号的PAPR有较好的抑制效果。 展开更多
关键词 雷达通信一体化 非正交多址 功率分配 峰均包络比 主动星座图扩展
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The relationship of blood cell-associated inflammatory indices and diabetic retinopathy: a Meta-analysis and systematic review 被引量:10
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作者 Wen-Juan Luo Wen-Fang Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第2期312-323,共12页
AIM: To explore the correlation between several blood cell-associated inflammatory indices including mean platelet volume(MPV), platelet distribution width(PDW), neutrophil to lymphocyte ratio(NLR) and platelet-lympho... AIM: To explore the correlation between several blood cell-associated inflammatory indices including mean platelet volume(MPV), platelet distribution width(PDW), neutrophil to lymphocyte ratio(NLR) and platelet-lymphocyte ratio(PLR), and the presence and severity of diabetic retinopathy(DR). METHODS: We searched for eligible studies from PubMed, EMBASE, Web of Science and CNKI up to December 13, 2017. Standardized mean difference(SMD) calculated with confidence interval(CI) of 95% was used to estimate the values of those indices. RESULTS: A total of 31 studies were included in the present Meta-analysis. As compared with type 2 diabetes mellitus(T2 DM) patients without DR, the values of MPV, PDW, NLR, and PLR were higher in patients with DR(SMD=0.67; 95%CI: 0.36 to 0.98; SMD=0.51; 95%CI: 0.27 to 0.75; SMD=0.77; 95%CI: 0.49 to 1.05 and SMD=1.18; 95%CI: 0.07 to 2.28). Additionally, it was also observed that MPV was closely correlated with the severity of DR. CONCLUSION: MPV, PDW, NLR, and PLR could be recommended as diagnostic biomarkers for DR, and MPV could be applied to assess the severity of DR. 展开更多
关键词 mean PLATELET volume PLATELET distribution width NEUTROPHIL to LYMPHOCYTE ratio platelet-lymphocyte ratio diabetic RETINOPATHY
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