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Comparison of different preoperative objective nutritional indices for evaluating 30-d mortality and complications after liver transplantation 被引量:1
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作者 Chuan Li Hong-Xia Chen Yan-Hua Lai 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期143-154,共12页
BACKGROUND The nutritional status is closely related to the prognosis of liver transplant re-cipients,but few studies have reported the role of preoperative objective nutri-tional indices in predicting liver transplan... BACKGROUND The nutritional status is closely related to the prognosis of liver transplant re-cipients,but few studies have reported the role of preoperative objective nutri-tional indices in predicting liver transplant outcomes.AIM To compare the predictive value of various preoperative objective nutritional indicators for determining 30-d mortality and complications following liver transplantation(LT).METHODS A retrospective analysis was conducted on 162 recipients who underwent LT at our institution from December 2019 to June 2022.RESULTS This study identified several independent risk factors associated with 30-d mor-tality,including blood loss,the prognostic nutritional index(PNI),the nutritional risk index(NRI),and the control nutritional status.The 30-d mortality rate was 8.6%.Blood loss,the NRI,and the PNI were found to be independent risk factors for the occurrence of severe postoperative complications.The NRI achieved the highest prediction values for 30-d mortality[area under the curve(AUC)=0.861,P<0.001]and severe complications(AUC=0.643,P=0.011).Compared to those in the high NRI group,the low patients in the NRI group had lower preoperative body mass index and prealbumin and albumin levels,as well as higher alanine aminotransferase and total bilirubin levels,Model for End-stage Liver Disease scores and prothrombin time(P<0.05).Furthermore,the group with a low NRI exhibited significantly greater incidences of intraabdominal bleeding,primary graft nonfunction,and mortality.CONCLUSION The NRI has good predictive value for 30-d mortality and severe complications following LT.The NRI could be an effective tool for transplant surgeons to evaluate perioperative nutritional risk and develop relevant nutritional therapy. 展开更多
关键词 Liver transplantation Nutritional indicator COMPLICATIONS PROGNOSIS Nutrition assessment
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Eco-physiological characteristics of Tetracentron sinense Oliv.saplings in response to different light intensities
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作者 Rong Wang Xueheng Lu +4 位作者 Hongyan Han Xuemei Zhang Yonghong Ma Qinsong Liu Xiaohong Gan 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期29-44,共16页
The regeneration of Tetracentron sinense Oliv.is poor in the understory and in open areas due to the charac-teristics of natural regeneration of the species on forest edges and in gaps.It is unclear whether different ... The regeneration of Tetracentron sinense Oliv.is poor in the understory and in open areas due to the charac-teristics of natural regeneration of the species on forest edges and in gaps.It is unclear whether different light intensities in various habitats affect eco-physiological characteristics of saplings and their natural regeneration.In this study,the light intensity in T.sinense habitats was simulated by artificial shading(L1:100%NS(natural sunlight)in the open;L2:50%NS in a forest gap or edge;L3:10%NS in understory)to investigate differences in morphology,leaf structure,physiology,and photosynthesis of 2-year-old sap-lings,and to analyze the mechanism of light intensity on sapling establishment.Significant differences were observed in morphology(including leaf area,and specific leaf area)under different light intensities.Compared to L1 and L3,chloroplast structure in L2 was intact.With increasing time,superoxide dismutase(SOD)and catalase(CAT)activities in L2 became gradually higher than under the other light intensities,while malondialdehyde(MDA)content was opposite.Shading decreased osmoregulation substance contents of leaves but increased chlorophyll.The results suggest that light intensities significantly affect the eco-physiological characteristics of T.sinense saplings and they would respond most favorably at intermediate levels of light by optimizing eco-physiological characteristics.Therefore,50%natural sunlight should be created to promote saplings establishment and population recovery of T.sinense during in situ conservation,including sowing mature seeds in forest edges or gaps and providing appropriate shade protection for seedlings and saplings in the open. 展开更多
关键词 Chloroplast ultrastructure eco-physiological characteristics Light intensities Sapling establishment Tetracentron sinense Oliv
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Evaluation of Ear and Facial Indices of Ibibio and Efik Female Children of Akwa Ibom and Cross River States, Nigeria
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作者 Nsikak Michael Umoh Kelechi Chinkata Uruakpa +7 位作者 Eru Eru Mba Michael Effiong Oku Theresa Isamoh Nnenna Williams Eric Agim Agaba Samson Omini Paulinus John Emah Gabriel Udo-Affah 《Journal of Biosciences and Medicines》 2024年第7期1-8,共8页
Background: The ear and face are indispensable and distinctive features for hearing and identification. Objectives: This study was designed to generate anthropometric data of the ear and facial indices of females of E... Background: The ear and face are indispensable and distinctive features for hearing and identification. Objectives: This study was designed to generate anthropometric data of the ear and facial indices of females of Efik and Ibibio children in Cross River and Akwa Ibom States, show morphological and aesthetic differences and ethnicity. Methods: A total of 600 female children (300 Efiks and 300 Ibibios) aged 2 to 10 years that met the inclusion criteria were chosen from selected primary schools in Calabar Municipality, Calabar South of Cross River State and from Uyo, Itu of Akwa Ibom State, Nigeria. Standardized measurements of face length, face width, ear length, and ear width were taken with a spreading caliper;the facial (proscopic) and ear (auricular) indices were determined. Results: Efik subjects presented a mean face length of 8.36 ± 0.06 cm, face width of 11.04 ± 0.04 cm, ear length of 4.92 ± 0.02 cm, and ear width of 3.06 ± 0.01 cm. Ibibio subjects had mean values for face length, face width, ear length, and ear width as 8.17 ± 0.05 cm, 10.75 ± 0.05 cm, 4.77 ± 0.03 cm, and 2.94 ± 0.02 cm respectively. The mean facial index and ear index for Efik subjects were 75.68 ± 0.31 and 62.16 ± 0.27 respectively;while the mean facial and ear indices for Ibibio subjects were 74.79 ± 0.36 and 61.80 ± 0.34 respectively. Statistical analysis demonstrated significant differences in face length, ear length, ear width and facial index, with the Efik subjects having higher values than Ibibio subjects (p Conclusion: The results showed hypereuryproscopic face as the prevalent face type among females of both ethnic groups, therefore can be of importance in sex, ethnic, and racial differentiation, and in clinical practice, aesthetics and forensic medicine. 展开更多
关键词 ANTHROPOMETRY EAR Facial indices Identification NIGERIA
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Overweight/Obesity in University Students from Mexico: Comparison Using Different Indices
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作者 Gabriel Medrano-Donlucas Claudia Carolina Hernández-Peña +4 位作者 Ricardo Juárez-Lozano Cecilia López-López Santiago C. Sigrist Flores Rafael Villalobos-Molina Itzell A. Gallardo-Ortíz 《Journal of Biosciences and Medicines》 2024年第7期151-159,共9页
The goal was to compare body mass index (BMI), waist circumference (WC), waist to height ratio (WHtR), and relative fat mas (RFM), to identify the best predictor of overweight and obesity in university students from M... The goal was to compare body mass index (BMI), waist circumference (WC), waist to height ratio (WHtR), and relative fat mas (RFM), to identify the best predictor of overweight and obesity in university students from Mexico. This is a cross-sectional survey with 697 university students from northern and central Mexico (448 women, and 249 men aged 18 - 19 years). Data was collected during 2018. Overweight and obesity were calculated from those indices and for both, female and male students, the order of correlation between a pair of indices were WHtR vs. RFM > WHtR vs. WC > RFM vs. WC > WHtR vs. BMI > BMI vs. WC > RFM vs. BMI. It is concluded to use the WHtR and the RFM to better predict overweight and obesity in young Mexican university students. 展开更多
关键词 Overweight and Obesity ANTHROPOMETRY Anthropometry indices
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Extreme value theory applied to the auroral electrojet indices
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作者 Si Chen Hong Yuan +2 位作者 Yong Wei Guang Yang FengZheng Yu 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期375-381,共7页
The study of extreme weather and space events has gained paramount importance in modern society owing to rapid advances in high technology.Understanding and describing exceptional occurrences plays a crucial role in m... The study of extreme weather and space events has gained paramount importance in modern society owing to rapid advances in high technology.Understanding and describing exceptional occurrences plays a crucial role in making decisive assessments of their potential impact on technical,economic,and social aspects in various fields.This research focuses on analyzing the hourly values of the auroral electrojet(AE)geomagnetic index from 1957 to 2019 by using the peak over threshold method in extreme value theory.By fitting the generalized Pareto distribution to extreme AE values,shape parameter indices were derived,revealing negative values that establish an upper bound for this time series.Consequently,it became evident that the AE values had reached a plateau,suggesting that extreme events exceeding the established upper limit are rare.As a result,although the need for diligent precautions to mitigate the consequences of such extreme events persists,surpassing the upper limit of AE values becomes increasingly challenging.It is also possible to observe an aurora in the middle-and low-latitude regions during the maximum period of the AE index. 展开更多
关键词 auroral electrojet indices extreme value theory extreme events
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Estimating wheat spike-leaf composite indicator(SLI)dynamics by coupling spectral indices and machine learning
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作者 Haiyu Tao Ruiheng Zhou +6 位作者 Yining Tang Wanyu Li Xia Yao Tao Cheng Yan Zhu Weixing Cao Yongchao Tian 《The Crop Journal》 SCIE CSCD 2024年第3期927-937,共11页
The contribution of spike photosynthesis to grain yield(GY)has been overlooked in the accurate spectral prediction of yield.Thus,it’s essential to construct and estimate a yield-related phenotypic trait considering s... The contribution of spike photosynthesis to grain yield(GY)has been overlooked in the accurate spectral prediction of yield.Thus,it’s essential to construct and estimate a yield-related phenotypic trait considering spike photosynthesis.Based on field and spectral reflectance data from 19 wheat cultivars under two nitrogen fertilization conditions in two years,our objectives were to(i)construct a yield-related phenotypic trait(spike–leaf composite indicator,SLI)accounting for the contribution of the spike to photosynthesis,(ii)develop a novel spectral index(enhanced triangle vegetation index,ETVI3)sensitive to SLI,and(iii)establish and evaluate SLI estimation models by integrating spectral indices and machine learning algorithms.The results showed that SLI was sensitive to nitrogen fertilizer and wheat cultivar variation as well as a better predictor of yield than the leaf area index.ETVI3 maintained a strong correlation with SLI throughout the growth stage,whereas the correlations of other spectral indices with SLI were poor after spike emergence.Integrating spectral indices and machine learning algorithms improved the estimation accuracy of SLI,with the most accurate estimates of SLI showing coefficient of determination,root mean square error(RMSE),and relative RMSE values of 0.71,0.047,and 26.93%,respectively.These results provide new insights into the role of fruiting organs for the accurate spectral prediction of GY.This high-throughput SLI estimation approach can be applied for wheat yield prediction at whole growth stages and may be assisted with agronomical practices and variety selection. 展开更多
关键词 Wheat spike photosynthesis Yield-related phenotypic trait Spectral indices Machine learning Estimation
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Platelet indices as predictors of poor glucoregulation in type 2 diabetes mellitus adults at Bishoftu General Hospital,Ethiopia
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作者 Dereje Abebe Regassa Gebeyaw Arega Berihun +3 位作者 Bisrat Fikadu Habtu Woyesa Beyene Haile Rahel Shumi Nagaash Girum Tesfaye Kiya 《World Journal of Diabetes》 SCIE 2024年第9期1889-1902,共14页
BACKGROUND Diabetes is a chronic metabolic syndrome that has become a global public health problem with significant morbidity and mortality.It is a pro-inflammatory and pro-thrombotic condition characterized by increa... BACKGROUND Diabetes is a chronic metabolic syndrome that has become a global public health problem with significant morbidity and mortality.It is a pro-inflammatory and pro-thrombotic condition characterized by increased platelet activation and alterations in platelet indices.However,the use of platelet indices as predictors of poor glucoregulation has not been fully evaluated in this context,and evidence for their role as predictors of poor glycemic status in diabetic patients is limited.AIM To evaluate platelet indices and determine their prognostic significance in relation to inadequate glucoregulation among individuals diagnosed with type 2 diabetes at Bishoftu General Hospital in Ethiopia,from June 15 to August 12,2022.METHODS A comparative cross-sectional study was conducted in 261 participants including 174 individuals with type 2 diabetes mellitus(T2DM)and 87 non-diabetic controls.The systematic random sampling technique was used to select participants.Data were collected using structured questionnaires,physical measurements,checklists,and laboratory tests.Platelet parameters and fasting blood glucose levels were determined from blood samples using Sysmex-XN550 and CobasC311 analyzers,respectively.The hematology analyzer output was checked and participants were also screened for malaria parasites using a prepared blood smear.Collected data were entered into Epi-data version 3.1 and exported to SPSS version 25 for analysis.Theχ^(2) test,Mann-Whitney U test,Kruskal-Wallis test,post hoc test,Spearman correlation,and receiver operating characteristic curve were used for analysis.A P value<0.05 was considered statistically significant.RESULTS The results of our study indicate that diabetic patients have significantly higher levels of platelet distribution width(PDW),mean platelet volume(MPV),platelet large cell ratio(PLCR),and plateletcrit(PCT)compared to healthy individuals(P<0.001).Furthermore,these indices were found to be significantly elevated in individuals with poor glycemic control in T2DM compared to those with good glycemic control and healthy controls.We also observed significant correlations between these indices and various anthropometric and clinical variables.Our findings suggest that PDW,with a cut-off value of 15.75 fL and an area under the curve(AUC)of 0.803,MPV,with a cut-off value of 12.25 fL and an AUC of 0.774,PLCR,with a cut-off value of 36.3%and an AUC of 0.775,and PCT,with a cut-off value of 0.24%and an AUC of 0.761,can serve as predictors of poor glycemic control in patients with diabetes mellitus.CONCLUSION The observed correlation between diabetic patients and a significant increase in platelet indices has highlighted their potential as predictors of poor glycemic control in diabetes.Therefore,regular screening and profiling of platelet indices is recommended as part of the follow-up process for individuals with diabetes mellitus. 展开更多
关键词 Platelet indices Type 2 diabetes mellitus CONTROLS ADULT Ethiopia
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Analysis on characteristics of extreme precipitation indices and atmospheric circulation in Northern Shanxi
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作者 Xia Cai Yan Song +3 位作者 Lin Cai Xin Su GuiHua Liang YanMing Xu 《Research in Cold and Arid Regions》 CSCD 2024年第2期84-97,共14页
This article utilizes daily precipitation data from 28 national meteorological stations in northern Shanxi Province spanning from 1972 to 2020,and the US NCEP/NCAR monthly average reanalysis and ERA5 monthly average r... This article utilizes daily precipitation data from 28 national meteorological stations in northern Shanxi Province spanning from 1972 to 2020,and the US NCEP/NCAR monthly average reanalysis and ERA5 monthly average reanalysis data.The study employs techniques such as empirical orthogonal function(EOF)decomposition,MannKendall mutation and other methods to investigate the spatiotemporal distribution of extreme precipitation index in northern Shanxi and their correlation with atmospheric circulation.The research results show that:the absolute index,relative index,intensity index and sustained dry period index(CDD)in the continuous index appear from southwest to northeast.The spatial distribution characteristics of the central region decrease,while the continuous wet period(CWD)decreases from the central to the east and west.The three indices Rx1day,Rx5day,and CWD mutated in 1978,1975,and 1983 respectively,and other extreme precipitation indices all appeared in a sudden change from a low-value period to a high-value period occurred around 2010.In the high-value years of the summer extreme precipitation index,there is a significant negative anomaly in the height field in the mid-high latitude regions of Eurasia.Northern Shanxi is controlled by a broad low-pressure trough in the Lake Baikal area.Water vapor transported via the east,west,and south routes converges in the northern Shanxi region and encounters cold air from the north.There is a strong upward motion anomaly at 500 hPa in the troposphere,and the dynamic conditions of upper-level divergence and lower-level convergence lead to more summer extreme precipitation in the northern Shanxi region.Conversely,in the low-value years of the summer extreme precipitation index,northern Shanxi is affected by a strong high-pressure ridge north of Lake Baikal.There is a downward motion anomaly at 500 hPa,and the northern Shanxi region lacks water vapor.The cold and warm air cannot converge,and both the water vapor conditions and dynamic conditions are poor,which is not conducive to the production of extreme precipitation in northern Shanxi. 展开更多
关键词 Northern Shanxi Extreme precipitation indices Spatio-temporal distribution and evolution MUTATIONS Atmospheric circulation anomaly
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Effects of Fermented Puffed Feather Meal on Growth Performance,Serum Biochemical Indices,Meat Quality,and Intestinal Microbiota in Broilers
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作者 Lin Yu Chen Zhihui +9 位作者 Wu Hongzhi Ji Fengjie Liu Yang Li Jianing Yu Xilong Dou Renkai Yuan Hua Yang Qinghui Li Zhongyu Xu Liangmei 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第3期42-58,共17页
This study aimed to investigate the effects of fermented puffed feather meal(FPFM)on growth performance,serum biochemical indices,meat quality,and intestinal microbiota in Arbor Acres(AA)broilers.A single-factor desig... This study aimed to investigate the effects of fermented puffed feather meal(FPFM)on growth performance,serum biochemical indices,meat quality,and intestinal microbiota in Arbor Acres(AA)broilers.A single-factor design was adopted,and four treatments were administered with five replicates to 240 one-day-old AA broilers.The control group(group A)received a basal diet,while the experimental groups received a basal diet plus 33%(group B),67%(group C)and 100%(group D)FPFM,respectively.Compared with group A,(1)the average daily gain(ADG)in group C decreased(P<0.05),and the feed conversion ratio(FCR)in group D increased(P<0.05);(2)the level of serum urea nitrogen in treatment groups decreased(P<0.05),and the levels of triglyceride,high density lipoprotein,low density lipoprotein,cholesterol,and glucose contents in group D increased(P<0.05)at day 21;(3)the serum immunoglobulin M and immunoglobulin G in group B and the immunoglobulin A in group C increased(P<0.05)at day 21,and the serum immunoglobulin M and immunoglobulin G in group D decreased(P<0.05)at day 42;(4)the share force of breast muscle and thigh muscle in group D increased(P<0.05);(5)the villus height to crypt depth ratio in the jejunum of group B increased(P<0.05)at day 21,and the villus height in group C and D increased(P<0.05)at day 42;(6)the proteobacteria counts in the cecum digesta in treatment groups decreased(P<0.05)at day 21.The basal diet supplemented with 33%FPFM promoted protein metabolism,enhanced immunity and improved meat quality,promoted the digestion and absorption of nutrients,increased intestinal microbial diversity,and improved the content of beneficial bacteria without affecting the growth performance,it was possible to be used as a good substitute for fish meal. 展开更多
关键词 fermented puffed feather meal(FPFM) growth performance serum biochemical indices meat quality intestinal microbiota
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Detection of Burned Areas through Spectral Indices Analysis of Sentinel-2A Satellite Images in the Abokouamékro Wildlife Reserve (Central, Côte D’Ivoire)
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作者 Bob Kouakou Kouadio Sié Ouattara +3 位作者 Alain Clément Jean-Marc Gala Bi Zaouri Jean-Luc Kouadio Kouassi Jean-Luc Edouard Kouakou N’guessan 《Open Journal of Applied Sciences》 2024年第1期205-222,共18页
In Côte d’Ivoire, the recurring and unregulated use of bushfires, which cause ecological damage, presents a pressing concern for the custodians of protected areas. This study aims to enhance our comprehension of... In Côte d’Ivoire, the recurring and unregulated use of bushfires, which cause ecological damage, presents a pressing concern for the custodians of protected areas. This study aims to enhance our comprehension of the dynamics of burnt areas within the Abokouamékro Wildlife Reserve (AWR) by employing the analysis of spectral indices derived from satellite imagery. The research methodology began with the calculation of mean indices and their corresponding spectral sub-indices, including NDVI, SAVI, NDWI, NDMI, BAI, NBR, TCW, TCG, and TCB, utilizing data from the Sentinel-2A satellite image dated January 17, 2022. Subsequently, a fuzzy classification model was applied to these various indices and sub-indices, guided by the degree of membership α, with the goal of effectively distinguishing between burned and unburned areas. Following the classification, the accuracies of the classified indices and sub-indices were validated using the coordinates of 100 data points collected within the AWR through GPS technology. The results revealed that the overall accuracy of all indices and sub-indices declines as the degree of membership α decreases from 1 to 0. Among the mean spectral indices, NDVI-mean, SAVI-mean, NDMI-mean exhibited the highest overall accuracies, achieving 97%, 95%, and 90%, respectively. These results closely mirrored those obtained by sub-indices using band 8 (NDVI-B8, SAVI-B8, and NDMI-B8), which yield respective overall accuracies of 93%, 92%, and 89%. At a degree of membership α = 1, the estimated burned areas for the most effective indices encompassed 2144.38 hectares for NDVI-mean, 1932.14 hectares for mean SAVI-mean, and 4947.13 hectares for mean NDMI-mean. A prospective approach involving the amalgamation of these three indices could have the potential to yield improved outcomes. This study could be a substantial contribution to the discrimination of bushfires in Côte d’Ivoire. 展开更多
关键词 Spectral indices WILDFIRE Burned Areas Abokouamékro Wildlife Reserve Côte D’Ivoire
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Effects of Milk Replacer on the Performance and Blood Biochemical Indices in Lambs 被引量:13
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作者 郭爱伟 张力 +2 位作者 熊春梅 周学辉 苗小林 《Agricultural Science & Technology》 CAS 2008年第1期107-110,共4页
[Objective] In this study, the performance and blood biochemical indices in lamps fed on milk replacer were researched, the feasibility of early weaned in lamps was discussed. [Method] 37 of 10 days lambs of Suffolk... [Objective] In this study, the performance and blood biochemical indices in lamps fed on milk replacer were researched, the feasibility of early weaned in lamps was discussed. [Method] 37 of 10 days lambs of Suffolk(♂) x XiaoWeiHanYang( ♀ ) were randomly divided into group A, B, C, D for this experiment. Group A, B, C were fed by 3 milk-replacers containing milk for different protein source respectively, and ten Iambs in each group; group D (seven lambs) were fed by ewes as the control. The performance and blood biochemical indices of the lamps were determined. [ Result] The results showed that the average daily gains of 10 - 15 days of age was not significantly different between group A and D ( P 〉 O. 05 ), the control were higher significandy than the group B,C (P 〈0.05). The average daily gains of 16 -25, 26 -35 days of age were not significantly different in group A, B, C, D. The daily weight gains of Group A, B, C in 45 - 55 days of age were higher significantly than the control (P〈0.05 ). Plasma urea nitrogen (PUN) of group B and C were higher than group A significantly (P〈0.05 ) ;Total protein ( TP), Plasma albumin (ALB) and Plasma total amino acid were no significant difference among the other 3 groups (P〉0.05 ). [Conclusion] So, the milk-replacers were available for early-weaned lamb. 展开更多
关键词 Early-weaned lamb Milk replacer PERFORMANCE Blood biochemical indices
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Study of the Short-time Eco-physiological Response of Plant Leaves to Dust 被引量:20
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作者 陈雄文 《Acta Botanica Sinica》 CSCD 2001年第10期1058-1064,共7页
The short-time eco-physiological response to dust was measured for the leaves of 22 local popular plant species including roadside trees, fruit trees, forest trees and crop species in Beijing. The dust did affect the ... The short-time eco-physiological response to dust was measured for the leaves of 22 local popular plant species including roadside trees, fruit trees, forest trees and crop species in Beijing. The dust did affect the eco-physiology of leaves of these species. After being covered by dust the instant net photosynthetic rates of most plant species changed insignificantly, but it decreased by more than 35% for 5 species, and it increased by-more than 57% for Ginkgo biloba L. The respiration rates of 12 plant species increased significantly, but it decreased significantly for Malus pumila Mill. (M. communis D C.) and Cotinus coggygria (L.) Scop., and it changed insignificantly for the other 8 species. The transpiration rates of 5 plant species increased significantly, however, they decreased for 9 species, and changed insignificantly for the other 8 species. Platanus occidentalis L. had highest dust carrying capacity. After 2 h the physiological indices did not change significantly for Diospyros kaki L. f., G. biloba and Populus tomentosa Carr. The implications of the research are that Ulmus laevis Pall., M. pumila (M. communis), D. kaki and G. biloba are suitable for amelioration of dust storm damage and increase in local economical development near the sources of dust storms in western China. And in the cities, such as Beijing and other dust areas, the plants have high dust-carrying capacity can be planted for air cleaning. 展开更多
关键词 LEAVES eco-physiological response DUST
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Winter Wheat Salt Tolerance Appraisal Indices with Varied Mineral Content of Saline Water 被引量:1
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作者 曹彩云 党红凯 +4 位作者 李科江 马俊永 郑春莲 王广才 李伟 《Agricultural Science & Technology》 CAS 2014年第7期1134-1139,共6页
[Objective] The aim was to study wheat salt resistance appraisal indicators under the condition of saline water irrigation.[Method] A trial was conducted with five varieties irrigated with saline water at 1,2,4,6,and ... [Objective] The aim was to study wheat salt resistance appraisal indicators under the condition of saline water irrigation.[Method] A trial was conducted with five varieties irrigated with saline water at 1,2,4,6,and 8 g/L during 2009-2010 and 2010-2011 in the research station of Dry-land Farming Institute of Hebei Academy of Agricultural and Forestry Sciences.With standardized indicators for measuring treatment,the response relations among different salt stress levels and winter wheat growth index were analyzed in this study.[Result] Under the condition of different salinity of irrigation,relative plant height after jointing stage,relative leaf area index,relative dry matter weight,relative ear number per unit area showed significant differences among treatments and yield showed significant correlation,which can be taken as salt-resistance examination index of wheat.[Conclusion] The results showed that the relative height after jointing stage was recommended as the most practical salt-tolerance appraisal indices,because it was easy to be observed and sensitive to salt stress. 展开更多
关键词 Winter wheat Mineral content Salt tolerance Appraisal indices
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Comparative Study on the Dwarfing Pre-selected Indices of Pear Germplasms with Different Growth Potentials
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作者 徐颖 曹后男 +2 位作者 宗成文 巩艳明 朴永虎 《Agricultural Science & Technology》 CAS 2009年第6期108-110,143,共4页
[ Objective] The aim of this study was to provide a theoretical basis for breeding selection, matching parents and the identification of traits during early period. [ Method ] With Shanli ( Pyrus ussuriensis Maxim) ... [ Objective] The aim of this study was to provide a theoretical basis for breeding selection, matching parents and the identification of traits during early period. [ Method ] With Shanli ( Pyrus ussuriensis Maxim) , S2 × Shanli (vigorous), S2 x ShanU (dwarfing), S2, super-dwarfing germplasm as the matedais, the dwarfing traits of each germplasm were identified by indices including leaf stomata density, branch-cortex ratio, leaf thickness, palisade tissue thickness, paisade-spongy ratio and vessel density. [Result] Among five kinds of pear germplasms, Shanli with strong growth potential had the smallest branch-cortex ratio, leaf thickness, palisade tissue thickness and palisade-spengy ratio, but the largest stomata density and vessel density. On the contrary, super-dwarfing germplasm with weak growth potential had the largest branch-cortex ratio, leaf thickness, palisade tissue thickness and palisade-spongy ratio, but the smallest stomata density and vessel density. There was a difference in stomata density, branch-cortex ratio, leaf thickness, palisade tissue thickness, palisade-spongy ratio and vessel density for every germplasm. [ Conclusion] Stomata density, branch-cortex ratio, leaf thickness, palisade tissue thickness, palisade-spongy ratio and vessel density can be used as indices of identification for pear growth potential in early period. 展开更多
关键词 PEAR DWARFING Pre-selected indices
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Spatial Characteristics of Temperature Indices of Climate Change in China
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作者 王大钧 胡春丽 徐智鑫 《Meteorological and Environmental Research》 CAS 2010年第8期52-54,61,共4页
Based on the temperature indices established by expert group on the detection,monitoring and indices of climate change,spatial characteristics of temperature indices from 278 meteorological stations in China during 19... Based on the temperature indices established by expert group on the detection,monitoring and indices of climate change,spatial characteristics of temperature indices from 278 meteorological stations in China during 1961-2008 were studied.The results showed that day number of freezing point went down gradually from northwest to southeast,as well as the most regions of China.Day number of summer was mostly over 50 d in China and over 100 d in Eastern China except for the most part of Northeast China,while there was an increase trend in the most regions of China.Growth period was generally above 150 d in China and increased with the decrease of latitude from north to south,while the trend coefficient of growth period in 236 stations was positive. 展开更多
关键词 indices of climate change Day number of freezing point Day number of summer Growth period China
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Evaluation Model of Carrying Capacity of Water Resources Based on Standardized Indices of Radial Basis Function
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作者 臧蕾 李祚泳 刘伟 《Agricultural Science & Technology》 CAS 2012年第6期1365-1367,共3页
[Objective] The aim was to study on RBF model about evaluation on carrying capacity of water resources based on standardized indices. [Method] The indices were transformed and the averages of standard values in differ... [Objective] The aim was to study on RBF model about evaluation on carrying capacity of water resources based on standardized indices. [Method] The indices were transformed and the averages of standard values in different levels were taken as the standardized values of components of central vectors for basic functions of RBF hidden nodes. Hence, the basic functions are suitable for most indices, simplifying expression and calculation of basic functions. [Result] RBF models concluded through Monkey-king Genetic Algorithm with weights optimization are used in evaluation on water carrying capacity in three districts in Changwu County in Shaanxi Province, which were in consistent with that through fuzzy evaluation. [Conclusion] RBF, simple and practical, is universal and popular. 展开更多
关键词 indices standardization RBF Water resource Carrying capacity Evaluation model
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Measuring urban sprawl in Beijing with geo-spatial indices 被引量:13
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作者 JIANG Fang LIU Shenghe +1 位作者 YUAN Hong ZHANG Qing 《Journal of Geographical Sciences》 SCIE CSCD 2007年第4期469-478,共10页
Concerning about the rapid urban growth in recent China, this study takes Beijing as a case and puts forward that urban sprawl can be measured from spatial configuration, urban growth efficiency and external impacts, ... Concerning about the rapid urban growth in recent China, this study takes Beijing as a case and puts forward that urban sprawl can be measured from spatial configuration, urban growth efficiency and external impacts, and then develops a geo-spatial indices system for measuring sprawl, a total of 13 indicators. In order to calculate these indices, different sources data are selected, including land use maps, former land use planning, land price and floor-area-ratio samples, digitized map of the highways and city centers, population and GDP statistical data, etc. Various GIS spatial analysis methods are used to spatialize these indices into 100mx100m cells. Besides, an integrated urban sprawl index is calculated by weight sum of these 13 indices. The application result indicates that geo-spatial indices system can capture most of the typical features and interior differentia of urban sprawl. Construction land in Beijing has kept fast growing with large amount, low efficiency and disordered spatial configuration, indicating a typical sprawling tendency. The following specific sprawl features are identified by each indicator: (1) typical spatial configuration of sprawling: obvious fragmentation and irregularity of landscape due to unsuccessful enforcement of land use planning, unadvisable pattern of typical discontinuous development, strip development and leapfrog development; (2) low efficiency of sprawl: low development density, low population density and economic output in newly developed area; and (3) negative impacts on agriculture, environment and city life. According to the integrated sprawl index, the sprawling amount in the northern part is larger than that in the southern, but the sprawling extent is in converse case; most sprawling area include the marginal area of the near suburbs and the area between highways, etc. Four sprawling patterns are identified: randomly expansion at urban fringe, strip development along or between highways, scattered development of industrial land, leapfrog development of urban residence and industrial area. 展开更多
关键词 urban sprawl MEASUREMENT geo-spatial indices BEIJING
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Indices of the Summertime Western North Pacific Subtropical High 被引量:17
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作者 陆日宇 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2002年第6期1004-1028,共25页
By averaging June-July-August (JJA) mean geopotential height anomalies at 850 hPa over the specified areas, the author proposes two innovative and succinct parameters to objectively define the zonal and meridional dis... By averaging June-July-August (JJA) mean geopotential height anomalies at 850 hPa over the specified areas, the author proposes two innovative and succinct parameters to objectively define the zonal and meridional displacements of the western North Pacific subtropical high (WNPSH) in summer, respectively. Thus, these two indices and the present results may provide a basis for validating atmospheric general circulation models simulating the WNPSH. For the zonal index, the specified area is the west edge (110°–150°E, 10°–30°N) of the WNPSH. For the meridional index, the specified area is the northwest edge (120°–150°E, 30°–40°N) of the WNPSH. The interannual variations of these two indices are found to be independent. The results from a composite analysis based on the meridional index are in good agreement with previous studies based on case analyses. The two indices are compared with the existing indices announced by the National Climate Center (NCC) in China, on the interannual timescale. Despite slight differences, the interannual variations of the presented indices are basically similar to those of the NCC indices, and thus the circulation and precipitation associated with the present indices exhibit similar features to those associated with the NCC indices. Furthermore, an analysis of the differences between the associations of the present indices and the NCC indices shows that the presented indices are better than the NCC indices. An important result is that the zonal index is related to a more outstanding anomaly of precipitation, especially in East Asia and the Philippine Sea, both based on the presented indices and the NCC indices. The two indices can also be used to describe the seasonal march of the WNPSH during summer, namely, the poleward and eastward shifts. It is found that climatologically, the WNPSH shifts poleward and eastward rapidly in middle July, but the amplitudes of the poleward and eastward shifts are more remarkable in the summers when the WNPSH is located poleward and eastward in average. 展开更多
关键词 WNPSH indices interannual variability seasonal evolution
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Comprehensive early warning of rock burst utilizing microseismic multi-parameter indices 被引量:17
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作者 Linming Dou Wu Cai +1 位作者 Anye Cao Wenhao Guo 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2018年第5期767-774,共8页
Rock bursts have become one of the most severe risks in underground coal mining and its early warning is an important component in the safety management. Microseismic(MS) monitoring is considered potentially as a powe... Rock bursts have become one of the most severe risks in underground coal mining and its early warning is an important component in the safety management. Microseismic(MS) monitoring is considered potentially as a powerful tool for the early warning of rock burst. In this study, an MS multi-parameter index system was established and the critical values of each index were estimated based on the normalized multi-information warning model of coal-rock dynamic failure. This index system includes bursting strain energy(BSE) index, time-space-magnitude independent information(TSMII) indices and timespace-magnitude compound information(TSMCI) indices. On the basis of this multi-parameter index system, a comprehensive analysis was conducted via introducing the R-value scoring method to calculate the weights of each index. To calibrate the multi-parameter index system and the associated comprehensive analysis, the weights of each index were first confirmed using historical MS data occurred in LW402102 of Hujiahe Coal Mine(China) over a period of four months. This calibrated comprehensive analysis of MS multi-parameter index system was then applied to pre-warn the occurrence of a subsequent rock burst incident in LW 402103. The results demonstrate that this multi-parameter index system combined with the comprehensive analysis are capable of quantitatively pre-warning rock burst risk. 展开更多
关键词 ROCK BURST Microseismic(MS)monitoring MULTI-PARAMETER indices COMPREHENSIVE EARLY WARNING
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New emergy indices for sustainable development 被引量:7
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作者 LUHong-fang LANSheng-fang +1 位作者 LILei PENGShao-lin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第4期562-569,共8页
The emergy indices for the evaluation of system's sustainable development ability were studied. Results indicated that the emergy indices are simplified and merged, and a new emergy index for sustainable developme... The emergy indices for the evaluation of system's sustainable development ability were studied. Results indicated that the emergy indices are simplified and merged, and a new emergy index for sustainable development(EISD) is deduced. Employing EISD, two cases are conducted. The first one is to compare three different dike pond agro ecological engineering modes, which are: melon melon cabbage four domestic fishes(mode Ⅰ), melon melon cabbage pig four domestic fishes (mode Ⅱ) and melon melon cabbage pig four domestic fishes combined with Siniperca chuatsi B. ( mode Ⅲ). The result is that the EISD of mode Ⅰ is 0.53. ModeⅡ's EISD is 5.26 times of mode Ⅰ, and mode Ⅲ's EISD is 6.83 times of mode Ⅰ. The second one is to evaluate the development of Zhongshan City, Pearl Delta, during 1996 to 2000. The result indicated that the EISD of Zhongshan had appreciably declined from 1996 to 1998, and quickly improved from 1998 to 2000, partly because of its environment protection and product construction. Both of the two cases studies showed that EISD can assessment the sustainable development ability more roundly, with the consideration of environmental impact and social\|economic effect at the same time. 展开更多
关键词 indices EMERGY sustainable development
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