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Chinese Science Bulletin 1998年第24期43卷 2082-2087页

作者： Jian Kang Fan Chen Naihu Wu Chinese Acad Sci Inst Dev Biol Beijing 100080 Peoples R China

The photoperiod_sensitive genic male sterile rice (PGMR) is particularly useful to take advantage of heterosis in rice. mRNA differential display was used to isolate the fertility_relative genes in rice. After establishing an optimized mRNA differential display system, one of the differential cDNA fragments that maybe related to the development and maturation of rice panicle was cloned from a PGMR Nongken 58S.

关键词： rice (Oryza sativa) fertility gene mRNA differential display.

Evaluation of soil fertility of the shelter-forest land along the Tarim Desert Highway

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Chinese Science Bulletin 2008年第S2期53卷 125-136页

作者： JIN ZhengZhong LEI JiaQiang XU XinWen LI ShengYu ZHAO SiFeng QIU YongZhi XU Bo Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China Graduate University of Chinese Academy of Sciences Beijing 100049China Agricultural College of Shihhotze University Shihezi 832003China Tarim Branch PetroChina Company LimitedKorla 841000China

To study the changes of soil fertility of the shelter-forest land along the Tarim Desert Highway, soils from the forest land were collected at the layers of 0―10 cm, 10―20 cm, 20―30 cm. Different soil fertility parameters were measured, and quantitative evaluation of soil fertility was performed by the soil integrated fertility index (IFI). The main results show that the construction of the shelter forest along the Tarim Desert Highway improved the soil physical structure, increased soil porosity and enhanced wa- ter-holding capacity. With the increase of plantation time of the shelter forest, soil microbial biomass C, N, P and the activities of six types of enzyme were enhanced, which promoted the accumulation and transformation of soil nutrients of the forest land. Consequently, the soil nutrients in 12-year-old forest land were much higher than in the newer ones and drifting sand. However, soil salt content of the older forest land was higher owing to the drip-irrigation with salt water. Through the comprehensive evalua- tion, we found that soil fertility index in the forest land was enhanced with the forest age, and it had close correlations with the growth indices of the forest trees. In summary, construction of the shelterforest along the Tarim Desert Highway accelerated the improvement of aeolian soil in the forest land, and the soil fertility improved year by year. We conclude that the forest trees grow normally under the stress of the present drip-irrigation with salt water.

关键词： Tarim Desert Highway shelterforest land soil fertility quality comprehensive evaluation

Implication of sewage sludge increased application rates on soil fertility and heavy metals contamination risk

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Emerging Contaminants 2023年第1期9卷 41-52页

作者： Abdelmajid Achkir Abdelhakim Aouragh Mohammed El Mahi El Mostapha Lotfi Najoua Labjar Mohammed EL Bouch Moulay Lahcen Ouahidi Taruvinga Badza Hamid Farhane Tawfik EL Moussaoui Laboratory of Spectroscopy Molecular ModellingMaterialsNanomaterialsWater and EnvironmentCERN2DENSAMMohammed V University in Rabat10100Morocco National Laboratory for Studies and Pollution Monitoring-Ministry of Energy Mines and EnvironmentDepartment of EnvironmentRabatMorocco School of Agricultural Earth and Environmental SciencesUniversity of KwaZulu-NatalPrivate Bag X01ScottsvillePietermaritzburg3209South Africa Team of Anthropogenetic Sciences and Biotechnologies Faculty of SciencesChouaib Doukkali UniversityEl Jadida24000Morocco Resources Valorization Environment and Sustainable Development Research Team(RVESD)Department of MinesMines School of RabatAve Hadj Ahmed CherkaouiBP 753AgdalRabat53000Morocco

This paper aims to assess soil fertility and risk contamination parameters in response to increased amendment rates of sewage sludge application,under semi-arid climatic conditions of Morocco,using two soil textures:soil A(clay-silty)and soil B(sandy-clay)over two years.To this end,sewage sludge and soils treatments physicochemical parameters,heavy metals content,degree of pollution and associated risks were evaluated and compared to controlled soils.The results showed that all studied parameters changed significantly(pPb>Zn>Ni>Cd>Cr.Nevertheless,their concentrations were below the critical values established by the European Union for the agronomic use of soil.The obtained results of assessed parameters indicating SS degree of pollution and associated risks showed a low to a moderate contamination risks of heavy metals.Accordingly,environmental risks of sewage sludge application will be related to increase of heavy metals mainly in a long-term agricultural reuse.Thus,optimal management of sewage sludge application is recommended to ensure sustainability and benefits at the same time to master the contamination risks.

关键词： Sewage sludge Soil Land application fertility Heavy metals Risk assessment

Age at first marriage and its relation to fertility in Bangladesh

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Chinese Journal of Population,Resources and Environment 2013年第3期11卷 227-235页

作者： Mosammat Zamilun Nahar Mohammad Salim Zahangir S.M.Shafiqul Islam Department of Statistics University of Chittagong Department of Business Administration International Islamic University Chittagong

The 2007 Bangladesh Demographic and Health Survey(BDHS)data are exploited to examine the effects of socioeconomic and demographic factors on age at first marriage linkage to reproductive behavior of Bangladeshi women.The mean age at first marriage of women is found to be 15.48 years.Multivariate logistic regression technique shows that place of residence,religion,region,wealth index,education,and occupation are significantly important factors for determining age at first marriage.The relationship between marriage and fertility suggests that women who marry at a younger age produce more children than women who marry late.Findings of this study show that if the age at first marriage of adolescents is increased by 1 year,the age at first birth is postponed by 0.728 years.With the increase in age at first marriage,the fecundability of women sharply rises,whereas the proportion of temporary sterility decreases.Although there is a positive association between age at first marriage and age-specific marital fertility rates,the total parity per woman at the end of the reproductive period is expected to reduce by 0.196 for each 1-year delayed marriage.

关键词： age at first marriage age at first birth fertility multivariate logistic regression life table analysis

Resazurin reduction and other tests of semen quality and fertility of bulls

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Asian Journal of Andrology 1999年第3期1卷 109-114页

作者： Robert H.Foote Department of Animal Science Comell University Ithaca NY 14853-4801 USA

Aim: This study was undertaken to compare the reduction in color of two dyes methylene blue (MBRT) and resazurindye (RRT) with other tests of bull semen quality and to examine their relationship to fertility. Methods: One hundredsixty-four ejaculates from 59 bulls were examined, processed, and used for 30 016 inseminations. Results: Bulls usedin artificial insemination have been selected for high semen quality and fertility, and semen from these bulls averaged80.6 % unstained sperm, only 11% had abnormalities, and fertility ranged from 64 %to 76 %. The MBRT and RRTwere run with standardized sperm numbers to prevent sperm concentration from influencing the dye reduction time. Ashort RRT was correlated with higher fertility ( r = -0.26) but MBRT was not correlated ( r = -0.05, P >0.0,5).The correlations were low, but axe typical and reflect the statistical effect of the large binomial variance associated withpregnancy or nonpregnancy being coded as 1 or O. Conclusion: The fact that the RRT was significantly correlated withfertility when sperm numbers were standardized, and published reports that resazurin is useful for monitoring other semencharacteristics, indicate that this dye may provide valuable information not given by other simple laboratory tests. (AsianJ Androl 1999 Sep; 1: 109 - 114 )

关键词： fertility semen spermatozoa cattle resazurin reduction

Modelling fertility:an application of count regression models

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Chinese Journal of Population,Resources and Environment 2015年第4期13卷 349-357页

作者： Ranjita Pandey Charanjit Kaur Department of Statistics University of Delhi

Often the lifecycle data occur as count of the vital events and are recorded as integers.The purpose of this article is to model the fertility behavior based on religious,educational,economic,and occupational characteristics.The responses of classified groups according to these determinants are examined for significant influence on fertility using Poisson regression model(PRM) based on the National Family Health Survey-3 dataset.The observed and predicted probabilities under PRM indicate modal value of two children for the Poisson distribution modeled data.Presence of dominance of two child in the data motivates the authors to adopt multinomial regression model(MRM) in order to link fertility with various socioeconomic indicators responsible for fertility variation.Choice of the explanatory factors is limited to the availability of data.Trends and patterns of preference for birth counts suggest that religion,caste,wealth,female education,and occupation are the dominant factors shaping the observed birth process.Empirical analysis suggests that both the models used in the study perform similarly on the sample data.However,fitting of MRM by taking birth count of two as comparison category shows improved Akaike information criterion and consistent Akaike information criterion values.Current work contributes to the existing literature as it attempts to provide more insight into the determinants of Indian fertility using Poisson and MRM.

关键词： count data fertility Poisson model multinomial regression models

A RCK Model with Endogenous fertility and Exogenous Technological Change

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Wuhan University Journal of Natural Sciences 2000年第2期5卷 137-142页

作者： CAI Dong han College of Mathematics and Computer Science, Wuhan University, Wuhan 430072, China College of Mathematics and Computer Science Wuhan University Wuhan 430072 China

The technological change as an exogenous variable is introduced into the RCK model with endogenous fertility in this paper. It is proved that the model has at least a nonzero steady state and the nonzero steady state is unique when the parameters satisfies some conditions. By phrase protrait analysis, the unique nonzero steady state is saddle and the economy has a unique optimal growth path. The results obtained implies that the relationship between the technological change and population growth rate determinated by the economic structure and the parental ethies. For the economy in which the parents is selfish, promoting the technological change rate decreases the fertility at the steady state. On the other hand, for the economy in which the parents is less selfish, the fertility increases as the technological change rate increases.

关键词： C K model fertility technological change economic growth

Combining multiple imperfect data sources for small area estimation:a Bayesian model of provincial fertility rates in Cambodia

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Statistical Theory and Related Fields 2019年第2期3卷 178-185页

作者： Junni L.Zhang John Bryant Guanghua School of Management Center for Statistical Science and Center for Data SciencePeking UniversityBeijingPeople’s Republic of China Bayesian Demography Limited ChristchurchNew Zealand

Demographic estimation becomes a problem of small area estimation when detaileddisaggregation leads to small cell counts.The usual difficulties of small area estimation are compounded when the available data sources contain measurement errors.We present a Bayesianapproach to the problem of small area estimation with imperfect data sources.The overall modelcontains separate submodels for underlying demographic processes and for measurement processes.All unknown quantities in the model,including coverage ratios and demographic rates,are estimated jointly via Markov chain Monte Carlo methods.The approach is illustrated usingthe example of provincial fertility rates in Cambodia.

关键词： Measurement error Bayesian hierarchical model coverage errors fertility Cambodia small area estimation

fertility and pregnancy in inflammatory bowel disease

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World Journal of Gastroenterology 2001年第4期7卷 455-459页

作者： Elspeth Alstead Senior Lecturer and Consultant Physician Department of Adult and Paediatric GastroenterologySt.Bartholomew's and the Royal London School of Medicine and DentistryTurner StreetLondon El 2ADUK.

INTRODUCTIONInflammatory bowel disease(IBD)is a chronic disorder affecting young adults in the reproductive years.It is comon for both female and male patients with IBD to ask questions about IBD's effect on their relationships,sexual and reproductive function,in particular fertility,the outcome of pregnancy and its possible effets on the disease.An open discussion of the social situation and education targeted at these issues therefore forms an essential part of the management of any young person with IBD.the questions that are most commonly asked are summarised in Table 1.In order to answer these questions we need evidence.There are few large prospective case controlled studies to provide the information which is required but the available data,some of it from small observational studies,will be summarised in this chapter.

关键词： inflammatory bowel diseases:pregnancy complications pregnancy fertility