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ADMISSIBILITY OF LINEAR ESTIMATORS IN A GROWTH CURVE MODEL SUBJECT TO AN INCOMPLETE ELLIPSOIDAL RESTRICTION 被引量:2
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作者 张尚立 桂文豪 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期194-200,共7页
This article considers the admissibility of the linear estimators for the regression coefficients in the growth curve model subject to an incomplete ellipsoidal restriction. The necessary and sufficient conditions for... This article considers the admissibility of the linear estimators for the regression coefficients in the growth curve model subject to an incomplete ellipsoidal restriction. The necessary and sufficient conditions for linear estimators to be admissible in classes of the homogeneous and non-homogeneous linear estimators, respectively, are obtained under the quadratic loss function. They are generalizations of some existing results in literature. 展开更多
关键词 growth curve model ADMISSIBILITY linear estimator
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ASSESSMENT OF LOCAL INFLUENCE IN A GROWTH CURVE MODEL WITH RAO'S SIMPLE COVARIANCE STRUCTURE 被引量:2
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作者 白鹏 《Acta Mathematica Scientia》 SCIE CSCD 1999年第S1期555-563,共9页
The present paper deals with the problem of assessing the local influence in a growth curve model with Rao's simple covariance structure. Based on the likelihood displacement,the curvature measure is employed to e... The present paper deals with the problem of assessing the local influence in a growth curve model with Rao's simple covariance structure. Based on the likelihood displacement,the curvature measure is employed to evaluate the effects of some minor perturbations on the statistical inference, thus leading to the large curvature direction, which is the most critical diagnostic statistic in the context of the local influence analysis. As an application, the common covariance-weighted perturbation scheme is thoroughly considered. 展开更多
关键词 growth curve model Rao's simple covariance structure w-model Likelihood displacement curvATURE
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ADMISSIBILITY IN THE GENERAL GROWTH CURVE MODEL WITH RESPECT TO RESTRICTED PARAMETER SETS UNDER MATRIX LOSS FUNCTION 被引量:1
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作者 张尚立 覃红 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期27-38,共12页
In this paper, we study the issue of admissibility in the growth curve model with respect to restricted parameter sets under matrix loss function. We obtain some neces- sary and sufficient conditions that the linear e... In this paper, we study the issue of admissibility in the growth curve model with respect to restricted parameter sets under matrix loss function. We obtain some neces- sary and sufficient conditions that the linear estimators of KBL are admissible in the class of homogeneous linear estimators and in the class of non-homogeneous linear estimators under the growth curve model with respect to restricted parameter sets, respectively. 展开更多
关键词 growth curve model linear estimation ADMISSIBILITY incomplete ellipsoidalrestriction
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BAYESIAN LOCAL INFLUENCE ASSESSMENTS IN A GROWTH CURVE MODEL WITH GENERAL COVARIANCE STRUCTURE 被引量:1
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作者 白鹏 费宇 《Acta Mathematica Scientia》 SCIE CSCD 2000年第4期563-570,共8页
The objective of this paper is to present a Bayesian approach based on Kullback- Leibler divergence for assessing local influence in a growth curve model with general co- variance structure. Under certain prior distri... The objective of this paper is to present a Bayesian approach based on Kullback- Leibler divergence for assessing local influence in a growth curve model with general co- variance structure. Under certain prior distribution assumption, the Kullback-Leibler di- vergence is used to measure the influence of some minor perturbation on the posterior distribution of unknown parameter. This leads to the diagnostic statistic for detecting which response is locally influential. As an application, the common covariance-weighted perturbation scheme is thoroughly considered. 展开更多
关键词 growth curve model prior and posterior distribution Kullback-Leibler di- vergence Bayesianω-model curvATURE
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Comparative Study on Analysis and Fitting of Pudong Chicken Growth Curve 被引量:1
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作者 Lu Xuelin Zhao Lele +3 位作者 Li Hejun Xu Dong Wu Haomin Xu Weibin 《Animal Husbandry and Feed Science》 CAS 2018年第3期174-177,共4页
The objective of this paper was to study the growth and development laws of Pudong chicken. The growth curve of Pudong chicken (cock and hen) from 0 to 20 weeks was analyzed and fitted with three models(Gompertz, L... The objective of this paper was to study the growth and development laws of Pudong chicken. The growth curve of Pudong chicken (cock and hen) from 0 to 20 weeks was analyzed and fitted with three models(Gompertz, Logistic and Bertalanffy). It was concluded that the growth curves were appropriately fitted with three models, and fitness degree (R2)in growth data of Pudong chicken were all above 0.992. The Bertalanffy model was the most effective with the highest R2 for cock (R^2=0.995) and hen (R^2=0.999), respectively. With further analysis of fitted parameters for Logis- tic model of cock, 0-3 weeks' fitted values were significantly greater than measured values and 4-8 weeks' fitted values were lower than measured values. Compared with Logistic model, the values calculated by Gompertz model and Bertalanffy model were more coincident with the practical measuring values. For hens, 0-3 weeks' fitted values of Logistic model were significantly greater than measured values and 0-2 weeks' fitted values of Gompertz model were slightly greater than measured values, while the values calculated by Bertalanffy model best matched the observed values from actual measure. The results showed that Bertalanffy model used to estimate the growth weight of Pudong chicken was the best while Logistic model was the worst. So the fitness and analysis of growth curves of Pudong chicken are valid, which may be adopted to predict growth and development laws of Pudong chicken and provide reliable data for precise feeding and breeding. 展开更多
关键词 Pudong chicken growth curve FITTING ANALYSIS MODEL
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Environmental Pollution and Economic Growth in China: A Test of the Environmental Kuznets Curve 被引量:1
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作者 Jiaqi Hu Adrian Hernandez-del-Valle Miguel A. Martinez-Garcia 《Journal of Geoscience and Environment Protection》 2017年第10期92-100,共9页
We apply a two pronged approach to analyze the presence of Environmental Kuznets Curve, EKC, in three types of emissions in the People’s Republic of China from 1994 to 2014: a structural breakpoint analysis and a mod... We apply a two pronged approach to analyze the presence of Environmental Kuznets Curve, EKC, in three types of emissions in the People’s Republic of China from 1994 to 2014: a structural breakpoint analysis and a model based test. We apply it to PM2.5, industrial waste and domestic water pollution time series, and find evidence of EKC in all three types of emissions that require appropriate policy. 展开更多
关键词 Economic growth Environmental KUZNETS curve PM2.5 DOMESTIC Water POLLUTION Industrial Waste China
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Regularized quantile regression for SNP marker estimation of pig growth curves
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作者 L.M.A.Barroso M.Nascimento +8 位作者 A.C.C.Nascimento1 F.F.Silva N.V.L.Serao C.D.Cruz M.D.V.Resende F.L.Silva C.F.Azevedo P.S.Lopes S.E.F.Guimaraes 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第4期824-832,共9页
Background: Genomic growth curves are general y defined only in terms of population mean; an alternative approach that has not yet been exploited in genomic analyses of growth curves is the Quantile Regression(QR). Th... Background: Genomic growth curves are general y defined only in terms of population mean; an alternative approach that has not yet been exploited in genomic analyses of growth curves is the Quantile Regression(QR). This methodology allows for the estimation of marker effects at different levels of the variable of interest. We aimed to propose and evaluate a regularized quantile regression for SNP marker effect estimation of pig growth curves, as well as to identify the chromosome regions of the most relevant markers and to estimate the genetic individual weight trajectory over time(genomic growth curve) under different quantiles(levels).Results: The regularized quantile regression(RQR) enabled the discovery, at different levels of interest(quantiles), of the most relevant markers al owing for the identification of QTL regions. We found the same relevant markers simultaneously affecting different growth curve parameters(mature weight and maturity rate): two(ALGA0096701 and ALGA0029483)for RQR(0.2), one(ALGA0096701) for RQR(0.5), and one(ALGA0003761) for RQR(0.8). Three average genomic growth curves were obtained and the behavior was explained by the curve in quantile 0.2, which differed from the others.Conclusions: RQR allowed for the construction of genomic growth curves, which is the key to identifying and selecting the most desirable animals for breeding purposes. Furthermore, the proposed model enabled us to find, at different levels of interest(quantiles), the most relevant markers for each trait(growth curve parameter estimates) and their respective chromosomal positions(identification of new QTL regions for growth curves in pigs). These markers can be exploited under the context of marker assisted selection while aiming to change the shape of pig growth curves. 展开更多
关键词 GENOME association growth curve PIG QTL REGULARIZED QUANTILE regression
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Stochastic simulation of growth curves of Acidithiobacillus ferrooxidans 被引量:1
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作者 杨宇 彭宏 +2 位作者 邱冠周 柳建设 胡岳华 《Journal of Central South University of Technology》 EI 2006年第5期473-476,共4页
To reveal the low growth rate of Acidithiobacillus ferrooxidans, a stochastic growth model was proposed to analyze growth curves of these bacteria in a batch culture. An algorithm was applied to simulate the bacteria ... To reveal the low growth rate of Acidithiobacillus ferrooxidans, a stochastic growth model was proposed to analyze growth curves of these bacteria in a batch culture. An algorithm was applied to simulate the bacteria population during lag and exponential phase. The results show that the model moderately fits the experimental data. Further, the mean growth constant (K) of growth curves is obtained by fitting the logarithm of the simulating population data versus the generation numbers with the different initial population number (N0) and initial mean activity of population (A0). When N0 is 300 and 700 respectively, the discrepancy of K value is only 0.91%, however, A0 is 0.34 and 0.38 respectively, the discrepancy of K value is 19.53%. It suggests that the effect of A0 on the lag phase exceeds N0, though both parameters could shorten the lag phase by increasing their values. 展开更多
关键词 随机模拟 生长曲线 迟滞期 微生物
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Growth Curves Analysis of Five Meat Rabbit Breeds
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作者 LIHua LONGJi-rong 《Journal of Northeast Agricultural University(English Edition)》 CAS 2001年第2期111-114,共4页
The growth curves of five meat rabbit breeds are fitted in form of Gompertz model.The results are shown as follows:the goodness of fit is higher than 99 50%;considering the body weight at one hundred day?the maximum ... The growth curves of five meat rabbit breeds are fitted in form of Gompertz model.The results are shown as follows:the goodness of fit is higher than 99 50%;considering the body weight at one hundred day?the maximum weight(A)?the instantaneous relative growth rate(K)?the turning weight(W )?the turning age (t )?the early average daily gain (KW ) selection,the Checkered Giant(GG) and the New Zealand White (NN) are better than other meat breeds,the slauthter age should be at the age of 90 day. 展开更多
关键词 meat rabbit growth curves ANALYSIS
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Height/Length and Weight Growth Curves and Growth References of Children Aged 0 - 7 in Chongqing by GAMLSS
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作者 Qian Chen Jiaxiu Liu +1 位作者 Kaocong Tian Zhaohai Liu 《Health》 2020年第2期86-98,共13页
Aim: Using the generalised additive model for location, the scale and shape (GAMLSS), the standard of height (length), weight and percentage curve of children were formulated to understand the growth law in Chongqing ... Aim: Using the generalised additive model for location, the scale and shape (GAMLSS), the standard of height (length), weight and percentage curve of children were formulated to understand the growth law in Chongqing and to provide a reference for clinical and preventive health care work of paediatrics in West China. Methods: Data were collected from the health clinic dataset of children aged 0 - 7 years in the Department of Child Health Care of a Third-Class A hospital in Chongqing from 2010 to 2017. By applying the GAMLSS technology and taking D(μ, σ, ν, τ) as the specific distribution form, BCT as the link function, P-spline function and cubic splines function as the smoothing function, the unit value of age-specific standard deviation of height (length) and weight were obtained, and the percentile map was drawn. Results: Based on the principle of minimum AIC and SBC values, BCT distribution was chosen as the model of the link function. Fitting results of height (length) and weight parameters of boys and girls, standard deviation tables of age and percentile curves were obtained. Conclusions: This study was an exploration of using GAMLSS method to establish a reference value range in the field of children’s growth and development in China. It could supplement the relevant data of Chongqing area for Reference standard for growth and development of children under 7 years of age in China, and also provide a reference for the rational diagnosis of children’s short stature and malnutrition in Chongqing. 展开更多
关键词 CHILDREN HEIGHT WEIGHT growth curve GAMLSS
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Establishment and Analysis of Growth Curve of Muchuan Black Chicken
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作者 Chunlin YU Xiaosong JIANG +10 位作者 Huarui DU Chaowu YANG Zengrong ZHANG Bo XIA Chenming HU Xiaoyan SONG Xia XIONG Li YANG Han PENG Qingyun LI Mohan QIU 《Agricultural Biotechnology》 CAS 2018年第6期115-118,共4页
To find out the growth and development regularity,the growth curves of Muchuan black chicken at the age of 0-21 weeks were established by Logistic,Bertalanffy and Gompertz models in this study.The results showed that ... To find out the growth and development regularity,the growth curves of Muchuan black chicken at the age of 0-21 weeks were established by Logistic,Bertalanffy and Gompertz models in this study.The results showed that all the three models can well fit the growth curve of Muchuan black chicken with a degree above 0.988,while the Gompertz model and the Bertalanffy model was the best for hens and cocks,respectively.Finally,the weight of hens and cocks were analyzed according to their corresponding high fitting models.Results showed that the inflexion age of Muchuan black chicken was 6.8-6.9 weeks old with an inflexion weight of 692.98 g in hens and 805.57 g in cocks.In conclusion,it was feasible to establish the growth curve of Muchuan black chicken with Logistic,Bertalanffy and Gompertz model. 展开更多
关键词 Muchuan BLACK CHICKEN growth and development CUMULATIVE growth growth curve FITTING degree
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High Order Tensor Forms of Growth Curve Models
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作者 Zerong Lin Dongzhe Liu +2 位作者 Xueying Liu Lingling He Changqing Xu 《Advances in Linear Algebra & Matrix Theory》 2018年第1期18-32,共15页
In this paper, we first study the linear regression model and obtain a norm-minimized estimator of the parameter vector by using the g-inverse and the singular value decomposition of matrix X. We then investigate the ... In this paper, we first study the linear regression model and obtain a norm-minimized estimator of the parameter vector by using the g-inverse and the singular value decomposition of matrix X. We then investigate the growth curve model (GCM) and extend the GCM to a generalized GCM (GGCM) by using high order tensors. The parameter estimations in GGCMs are also achieved in this way. 展开更多
关键词 TENSOR GENERALIZED Linear MODEL growth curve MODEL Parameter Estimation GENERALIZED Inverse
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GENERAL ADMISSIBLE LINEARESTIMATORS IN RESTRICEDGROWTH CURVE MODEL
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作者 CHEN QINGPING ( Yunyang Teacher College ) 《郧阳师范高等专科学校学报》 1996年第3期1-6,共6页
In this paper, we give a class of fuation and use to dicuss general admissibility according to general optimality ceriteria defined uader restricted growth curve model. General admissible characterization are obtained... In this paper, we give a class of fuation and use to dicuss general admissibility according to general optimality ceriteria defined uader restricted growth curve model. General admissible characterization are obtained. Moreover, these conditions are then utilize to characterize infulueace that restrictions involved in growth curve model have on the class of admissible linear 展开更多
关键词 growth curve model LINEAR RESTRICTION Generaladmissble
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Growth and Inequality in Indonesia: Does Kuznets Curve Hold?
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作者 G. A. Diah Utari Retni Cristina 《Journal of Modern Accounting and Auditing》 2015年第2期93-111,共19页
关键词 库兹涅茨曲线 印度尼西亚 人均收入 经济增长 城镇人口 增长过程 农业部门 通货膨胀
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应用CurveExpert软件拟合生长曲线模型 被引量:7
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作者 李少斌 胡江 +2 位作者 王继卿 刘秀 罗玉柱 《畜牧兽医杂志》 2012年第5期57-59,共3页
介绍了应用CurveExpert软件拟合动物生长曲线模型的方法,并对该软件分析结果的可靠性进行了分析。结果表明,应用CurveExpert拟合动物生长曲线模型操作简便,结果准确,可为相同或类似曲线拟合提供参考。
关键词 生长曲线模型 软件 参数估计
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Inflation and Unemployment Trade-off:Is Phillips Curve True for African Developing Countries?Evidence from Sudan
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作者 Omer Allagabo Omer Mustafa 《Journal of Economic Science Research》 2021年第3期35-43,共9页
The relationship between wage inflation and unemployment(Phillips Curve)is controversial in economic thought,and the controversy is centered around whether there is always a trade-off or not.If this relati-onship is n... The relationship between wage inflation and unemployment(Phillips Curve)is controversial in economic thought,and the controversy is centered around whether there is always a trade-off or not.If this relati-onship is negative it is called The short-run Fillips Curve.However,in the long run,this relationship may probable not exist.The matter of how inflation and unemployment influence economic growth,is debatably among macroeconomic policymakers.This study examines the behavior of the Phillips Curve in Sudan and its effect on economic growth. 展开更多
关键词 Phillips curve Trade-off Economic growth SUDAN
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Nexus between CO2 Emissions and Economic Growth, Industrial Production, and Foreign Direct Investment in Vietnam: Symmetric ARDL Approach
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作者 Le Phuong Nam Ho Thi Hien +3 位作者 Nguyen Van Song Nguyen Manh Hieu Dao Thu Tra Nguyen Thi Luong 《Journal of Environmental Protection》 2023年第8期637-659,共36页
Vietnam’s economy has been developing strongly in recent years;however, it is necessary to examine the impact of its economic activities on environmental quality. This study aims to evaluate the relationship between ... Vietnam’s economy has been developing strongly in recent years;however, it is necessary to examine the impact of its economic activities on environmental quality. This study aims to evaluate the relationship between CO<sub>2</sub> emissions and economic growth, industrial production, and foreign direct investment (FDI) in Vietnam. The ARDL estimation was used to process the dataset from World Bank. Results showed that economic growth, industrial production, and FDI have an impact on CO<sub>2</sub> emissions in the long run in Vietnam. Granger Causality test also indicated that there is a causal relationship between economic growth, industrial production, and CO<sub>2</sub> emissions in Vietnam from 1990 to 2018, at 5% statistical significance level. Proposed solutions to reduce CO<sub>2</sub> emissions but still promote economic growth toward the green growth orientation and zero carbon target attainment are as follows: 1) reduce the use of fossil energy in industrial manufacturing and replace it by renewable energy sources;2) use modern technology for all production sectors in economy;and 3) develop a legal framework for FDI projects selection and choose foreign investors with modern and low carbon emission technology. 展开更多
关键词 Economic growth C O2 Emission FDI ARDL Environmental Kuznets curve (EKC)
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贵州地方鸡种体重生长曲线的拟合分析
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作者 龙霞 李维 +5 位作者 杨书含 李辉 吴胜 田应平 田旭玲 肖涛 《畜牧与兽医》 CAS 北大核心 2024年第1期1-5,共5页
为探究贵州省赤水乌骨鸡、黔东南小香鸡、乌蒙乌骨鸡、威宁鸡和贵州黄鸡这5个地方鸡种生长发育规律,采用Logistic、Gompertz和von Bertalanffy 3种非线性模型对5个地方鸡种的生长曲线进行拟合,选取5个品种鸡各60只,公母各30只,测定0、2... 为探究贵州省赤水乌骨鸡、黔东南小香鸡、乌蒙乌骨鸡、威宁鸡和贵州黄鸡这5个地方鸡种生长发育规律,采用Logistic、Gompertz和von Bertalanffy 3种非线性模型对5个地方鸡种的生长曲线进行拟合,选取5个品种鸡各60只,公母各30只,测定0、2、4、6、8、10、12、14、16、18周龄时的体重。结果:5个品种鸡的生长趋势一致,3个模型均能较好地拟合5个品种鸡的生长变化情况,拟合度均在0.98以上,其中von Bertalanffy模型对5个品种鸡的生长曲线拟合效果最好;同时期的鸡体重以贵州黄鸡最重,黔东南小香鸡最轻,赤水乌骨鸡、乌蒙乌骨鸡和威宁鸡相近;5个品种鸡的拐点周龄分别为9.2、7.9、7.3、8.9和8.4,拐点体重分别为870.71、509.18、708.29、834.35和945.52 g。通过拟合的生长曲线模型对鸡体重进行评估,可为贵州省地方鸡的科学饲养、品种资源利用及选育提供依据。 展开更多
关键词 地方鸡 品种 体重 生长曲线 拟合分析 贵州
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人口特征对中国经济社会需水影响及峰值预测
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作者 何国华 赵勇 +4 位作者 王浩 何凡 李海红 秦长海 朱翰林 《水科学进展》 EI CAS CSCD 北大核心 2024年第2期220-231,共12页
人口规模结构是决定水资源需求的关键因子,在人口总量负增长的重大变化背景下,中国经济社会需水如何演变直接关系到水资源管理宏观决策。本文通过分析中国人口城乡结构、年龄结构对经济社会需水的影响规律,构建了基于人口特征的需水变... 人口规模结构是决定水资源需求的关键因子,在人口总量负增长的重大变化背景下,中国经济社会需水如何演变直接关系到水资源管理宏观决策。本文通过分析中国人口城乡结构、年龄结构对经济社会需水的影响规律,构建了基于人口特征的需水变化曲线,并在此基础上预测了经济社会需水演变态势及峰值时点。研究结果表明:中国经济社会需水峰值可能出现在2042年,达峰规模约为7300亿m^(3);2050年之前,城镇地区需水总量将会持续增加,农村地区需水峰值将于2030年左右出现。经济社会需水规模是决定区域用水特征的边界条件,研究认为在中国经济社会需水还未到达拐点、国际贸易环境动荡加剧的背景下,未来中国供水保障还应该保持一定的弹性和韧性。 展开更多
关键词 需水峰值 人口负增长 城乡结构 年龄结构 需水变化曲线
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家兔支气管败血波氏杆菌的分离鉴定及耐药基因检测
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作者 曹洪志 李成贤 +2 位作者 彭茜翎 其美拉姆 史纪强 《饲料工业》 CAS 北大核心 2024年第5期70-76,共7页
为深入了解兔支气管败血波氏杆菌(Bordetella bronchiseptica,Bb),试验将病兔体内分离得到的菌株进行菌株鉴定、生长曲线测定、致病性研究、药敏试验及耐药基因检测,期望了解该菌的生长规律,为临床用药及防控奠定基础。通过Gram染色镜... 为深入了解兔支气管败血波氏杆菌(Bordetella bronchiseptica,Bb),试验将病兔体内分离得到的菌株进行菌株鉴定、生长曲线测定、致病性研究、药敏试验及耐药基因检测,期望了解该菌的生长规律,为临床用药及防控奠定基础。通过Gram染色镜检、分离培养、16S rDNA序列分析对分离菌株进行鉴定,测定了该分离株的生长曲线、半数致死量、耐药性并对分离菌株进行β-内酰胺酶耐药基因的检测。结果表明:分离得到1株革兰氏阴性杆菌,命名为P201215,该分离株的16S rDNA基因序列与GenBank中支气管败血波氏杆菌(登录号为NR113628.1)的同源性为99%。分离株的对数生长期为2~9 h,9 h后进入平台期;对KM小鼠的半数致死量为1.19×107 CFU。药敏试验结果显示,分离株对部分头孢菌素类药物耐药,对大部分β-内酰胺类、喹诺酮类、四环素类及氨基糖苷类药物敏感,PCR检测未检出超广谱β-内酰胺酶耐药基因。 展开更多
关键词 支气管败血波氏杆菌 分离鉴定 生长曲线 半数致死量 超广谱Β-内酰胺酶
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