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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
571

Impact of ethnicity on recent fertility change by marital status in Kazakhstan

Dyussupova, Saule January 2011 (has links)
CHARLES UNIVERSITY IN PRAGUE Faculty of Science Department of Demography and Geodemography PhD study program Mrg. Saule Dyussupova IMPACT OF ETHNICITY ON RECENT FERTILITY CHANGE BY MARITAL STATUS IN KAZAKHSTAN PhD dissertation Tutor: Prof. RNDr. Jitka Rychtaříková, CSc. Prague - 2011 Dedicated to my parents - Khanshaym and Tuyakh I declare that this dissertation is my own work under the supervisor of Prof. RNDr. Jitka Rychtaříková CSc. Where other sources of information have been used, they have been acknowledged. I agree that if any results gained while working on this thesis will be used outside the Charles University in Prague, written permission of the University will be necessary. I agree to lend this thesis for study reasons and agree that the thesis will be added to the borrower's database. In Prague, 14.05.2011 Saule Dyussupova Acknowledgements I would like to open the first paper of my dissertation with the deepest expression of gratitude to all teachers for their time, patience, and hard work, to those who made my study at the Charles University in Prague successful, exciting and pleasant. It was an unforgettable experience. You were always there to help and share knowledge, skills and ideas with me. My special words of appreciation go to my dear tutor Prof. RNDr. Jitka Rychtaříková CSc, whose...
572

Proměny plodnosti v nejnižších věkových skupinách matek z pohledu demografie / Fertility transformation in the youngest age from point of view of demography

Válková, Kateřina January 2012 (has links)
Fertility transformation in the youngest age from point of view of demography Abstract This thesis aims at evaluating fertility transformation in the youngest age in the 20th century and at the beginning of the 21st century in the Czech Republic. Circumstances and causes of transformation of fertility in this age group of women are based on usage of theoretical concepts related to fertility issues in the youngest age. The chosen period shows a number of changes in socioeconomic, political and legislative way. The transformation of the society in 20th century had influence on fertility level and fertility timing. Form of motherhood in the young age has changed also. Differences of characteristics of fertility in youngest age influenced by social evolution were shown on example of comparison of young women fertility evolution in Czech Republic, France and Romania. It approves that fertility level in the youngest age can be the driver of the social progression. Keywords: fertility, Czech Republic, young mother
573

Fertility decision making: to what extent do adaptations, social pressures, and individual differences influence plans to have a child?

Adair, Lora E. January 1900 (has links)
Master of Science / Department of Psychological Sciences / Gary Brase / An evolutionary perspective suggests that changes in resource availability produce changes in fertility decisions and desires, and that these adaptive mechanisms are sensitive to sociocultural factors that act more proximally to the decision-maker. The current work systematically investigates several factors as potential predictors of fertility decisions at the level of the individual decision-maker in a three-study design, adding to an existing literature of fertility decision-making that has focused on demographic-level shifts. In study 1 (N=228, 69.3% female, average age=25.6), study 2 (N=232, 72.4% female, average age=24.7), and study 3 (N=333, 67% female, average age=25.1) data was collected from a general Internet sample and a student sample. Findings suggest that high resource variability produces insecure romantic attachment, which is associated with increased fertility plans and desires. Further, this work indicates that fertility decision making mechanisms are sensitive to sociocultural factors, particularly gender roles and identities, cultural pressures to become a parent, mothering expectations, and relationship status. These findings suggest that demographic-level changes in fertility can be understood, with strong predictive models, at the individual-level of analysis.
574

Hormonal, estrual, ovulation and milk traits in postpartum dairy cows following multiple daily injections of oxytocin

Stewart, Robert Edwin. January 1986 (has links)
Call number: LD2668 .T4 1986 S73 / Master of Science / Animal Sciences and Industry
575

Synchronizace říje plemenic skotu a její úspěšnost

SUKOVÁ, Denisa January 2019 (has links)
Reproduction and milk production are considered to be the main factors influencing the whole economy of cattle breeding. We have been monitoring the worsening reproduction related to cattle breeding for a long time. The introduction of synchronization protocols into reproductive management is a posibility to improve reproduction. The aim of my work was to detect the success rate of insemination after rut synchronization on the basis of the data analysis and to evaluate reproductive indicators. The monitoring was performed from January 2017 to June 2018. There were monitored 310 breeding Holstein cows with the yield level of 10 335 kg of milk. The data were obtained from the zootechnical records and the Farmsoft Program. The breeding reproductive level was poor. Here are following values of reproductive indicators: insemination interval - 63 days, service period - 124 days, intervening time - 407 days, intersemination interval - 35 days, insemination index - 2,63 and pregnancy after the first insemination - 33,23%. That was only the insemination interval to achieve great results because breeding cows were involved into the synchronization protocol Presynch within 31 to 38 days after birth. It was detected that cows after the synchornization program Presynch got pregnant in 36,6% after the first insemination, whereas breeding cows being inseminated for the required rut became pregnant in 28% cases after the first insemination. The percentage of pregnancy in synchronizated cows after the first insemination is almost identical to the average in the Czech Republic (37,1%). Performing hormonal therapy within Presynch increased the reproductive costs in one cow by 211 Czech crowns.
576

Analýza reprodukčních vlastností prasnic ve vybraném chovu

KUČEROVÁ, Marie January 2019 (has links)
The aim of the thesis was to analyse the reproductive parameters of the CLW and CLWxCL sows group in selected breeding group (CLW - Czech Large White, CL - Czech Landrace). Sows, compared to gilts, had more all born piglets born after 100 services (by 118 piglets more after 1st insemination and 116 piglets more after all inseminations). The CLWxCL sows gave birth to 0.10 more all born piglets and 0.21 live piglets more. The highest number of piglets, all and live, was born in the 4th parity. The correlation coefficients between the age at the 1st service and the number of all resp. live-born piglets were low. Only 0.1 live piglets were born to CLW sows with weaning to service interval (WSI) from 5 days compared to WSI to 4 days. In CLWxCL sows, more live-born piglets showed sows with WSI to 4 days compared to sows with WSI from 5 days. The difference was higher, namely 0.8 piglet (P < 0.05). In the case of CLW and CLWxCL sows was confirmed a statistically significant difference in the number of live-born piglets between the sows with a gestation length from 116 days, up to 114 days and 115 days. Most of the piglets were born after AMD 74 boar and the lowest number after AMD 101 boar.
577

Early marriage and fertility outcomes in South-East Nigeria.

Ozumba, Chineme O. I. 20 March 2013 (has links)
Background: Despite the adverse demographic and health impact of early marriage, it still occurs in many developing nations including Nigeria. One of the outcomes of early marriage is increase in population size due to the number of years of exposure to the risk of pregnancy of women who marry early. Most of the research on early marriage has been carried out in the Northern and Western zones of the country. The objective of this study was to identify the relationship between early marriage and the outcomes of Number of Children Ever Born (NCEB) and Total Fertility Rate (TFR) in the South East Zone (SEZ) of the country. Methods: Univariate, bivariate and multivariate analysis were carried out on data obtained from 2008 Nigeria Demographic and Health Survey (NDHS) to determine the relationship between NCEB and age at first marriage as well as other independent variables such as woman’s level of education, wealth status, place of abode, husband’s educational level and marital status for ever married women aged 45-49 years. TFR was estimated for all ever married women in the South East Zone as well as those who married at <18 years and those who married at >=18 years of age. A sample size of 2175 comprising all ever married women in the SEZ was used for the study. Results: The findings indicate that there is a significant relationship between NCEB and Age at first marriage as well as woman’s level of education only. The TFR for women who married at <18 years and 18+ was 7.8 and 7.7 respectively. Conclusions: The study has shown that early marriage contributes in some measure to the number of children born in South Eastern Nigeria. However the level of significance is low. The seeming contradiction suggests that there are other influencing factors such as prevailing customs and traditions and shared experiences of the Igbos (the dominant tribe in the study area). Areas of further research are highlighted and recommendations for policy and program implementation are made.
578

Nutrição e crescimento do eucalipto em resposta a diferentes fontes e métodos de aplicação de cálcio / Growth and nutrition of eucalypts on response to differents sources and methods of calcium application

Macana, Yesid Alejandro Mariño 21 June 2017 (has links)
O eucalipto apresenta bom crescimento em solos com alta acidez trocável e ativa, sendo a calagem uma prática realizada com o objetivo de fornecer Ca2+ e Mg2+. No entanto, o seu efeito fica restrito à camada superficial do solo devido à baixa solubilidade dos constituintes neutralizantes. A aplicação de gesso agrícola promove a movimentação de Ca2+ e SO4-2 no perfil do solo, possibilitando a melhora do subsolo para favorecer o crescimento radicular. A maioria das plantações de eucalipto no Brasil é estabelecida em solos de baixa fertilidade, verificando-se respostas significativas à fertilização com o fim de garantir a sustentabilidade da produção a longo prazo. O objetivo do presente estudo foi avaliar o crescimento da parte aérea e radicular do eucalipto em resposta à fontes e métodos de aplicação de cálcio em um Neossolo Quartzarênico. Para tal fim, foram mensurados: i) os teores de cálcio, magnésio e enxofre no solo e nas folhas; ii) a densidade de raiz fina (DRF) por biomassa ao longo do perfil e a umidade no solo, e; iii) o crescimento em altura e no diâmetro à altura do peito das árvores de Eucalyptus. A fertilização com calcário dolomítico e calcário calcinado em faixa promoveu aumento nos teores de Ca2+ e Mg2+ trocáveis no solo, especialmente nas camadas superficiais. Os teores foliares de Ca, Mg, K e S encontram-se na faixa adequada nas três datas de amostragem. O volume de tronco das árvores foi superior com a aplicação do calcário dolomítico em faixa comparativamente à aplicação de calcário dolomítico em área total ou incorporado. A mistura de calcário dolomítico com a maior dose de gesso aumentou os teores Ca2+ e Mg2+ trocáveis no solo nas camadas superficiais. A aplicação de gesso aumentou expressivamente os teores de SO42- abaixo dos 40 cm de profundidade. A DRF foi superior com a ausência da aplicação das fontes de cálcio. Com a aplicação de gesso agrícola misturado com calcário dolomítico se obteve um volume de madeira similar à aplicação de calcário dolomítico. / Eucalyptus plantations have a good development in soils with high exchangeable and active acidity, therefore, being the liming an activity done with the goal of providing Ca2+ and Mg 2+. However, its effect is restricted to the surface layer due to the low solubility of neutralizing constituents. The application of gypsum promotes the movement of Ca2+ and SO4-2 in the soil profile providing a more adequate root growth. Most eucalyptus plantations in Brazil were established in soils of low fertility, verifying significant responses to fertilization in order to ensure the sustainability of long-term production. The aim of this study was to evaluate the nutrition and aerial and root growth of eucalypts in response to different sources and methods of application of calcium in a Quartzipsamment. It was measured: i) calcium, magnesium and sulfur levels in soil and leaf; ii) Fine root density along the profile and soil moisture; iii) Growth in height and DBH of E. urophylla plantation. The fertilization with dolomitic and calcitic limestone in furrows promoted an increase in Ca2+ and Mg2+ levels in the soil, especially in surface layers. The Ca2+ and Mg2+ foliar levels found in the good range in three times. The volume of eucalypts was increased with dolomitic limestone in furrows comparatively broadcasted distribution and incorporation of dolomitic limestone. The mix of dolomitic limestone and the high gypsum level increases Ca2+ and Mg2+ levels in the soil in surface layers. Gypsum increases SO42- levels below 40 cm deep. The fine root density was higher without calcium fertilization. The volume wood with gypsum more dolomitic limestone applied was similar compared with dolomitic limestone applied.
579

O estudo da função sexual e gonadal nas adolescentes com epilepsia / Evaluation of sexual and gonadal function in female adolescents with epilepsy

Vincentiis, Sílvia de 14 March 2008 (has links)
Em mulheres com epilepsia, sabe-se que a síndrome epiléptica, a freqüência de crises e as drogas antiepilépticas podem ter influência na função sexual, comportamento sexual e na capacidade reprodutora. Muitos fatores têm sido relacionados a estas alterações, tais como: duração e gravidade da epilepsia, tipo de droga antiepiléptica e localização da lesão epileptogênica. Baseado no conhecimento adquirido com as mulheres assume-se que as adolescentes sofram influência semelhante. Este estudo teve como objetivo avaliar aspectos relacionados à função e ao comportamento sexual, à educação sexual e à função gonadal em adolescentes do sexo feminino com epilepsia. Para isso, foram estudadas prospectivamente 35 pacientes do sexo feminino, com epilepsia parcial e generalizada, com idades entre 10 a 20 anos, com epilepsia ativa, sendo o diagnóstico da síndrome epiléptica realizado segundo os critérios da Liga Internacional Contra a Epilepsia (1989). Os critérios de exclusão foram: ausência de menarca; uso de contraceptivo hormonal ou dispositivo intra-uterino, no momento da avaliação ou nos últimos três meses; antecedente de cirurgia ginecológica ou distúrbio endocrinológico; presença de doença crônica associada, ou deficiência mental moderada a grave que impossibilitassem o seguimento do protocolo a ser instituído. As informações sobre a função sexual, comportamento sexual e a educação sexual das adolescentes com epilepsia foram avaliadas através de um questionário padrão. O protocolo de estudo da função gonadal incluiu a análise dos seguintes critérios: ciclo menstrual regular, presença de dismenorréia, dosagem dos níveis hormonais (FSH, LH, estradiol, progesterona, prolactina, testosterona, T3, T4 livre, TSH), ultra-sonografia pélvica, gestação em curso ou recente. A função gonadal foi considerada normal se pelo menos um ou mais parâmetros acima foi adequado. Não foi observada diferença entre a idade da primeira relação sexual (p=0,54), atividade sexual (p=0,23), libido (p=1,00) e orgasmo (p=0,23) entre as adolescentes com epilepsia, em relação ao grupo controle. Todas as adolescentes sexualmente ativas relataram o uso de métodos contraceptivos, porém apenas 20,1% com orientação de algum profissional de saúde. A idade da menarca nos dois grupos foi similar. No entanto, o uso de valproato próximo à menarca e crises freqüentes foram fatores antecipadores da menarca. As adolescentes com epilepsia apresentaram uma freqüência de ciclos menstruais irregulares superior à do grupo controle. A irregularidade menstrual relacionou-se com a presença de crises tônico-clônicas generalizadas (p=0,02), sem relação com a síndrome epiléptica. Houve uma tendência a irregularidades menstruais em adolescentes que apresentavam duração da doença mais prolongada (p=0,06), independente da freqüência de crises epilépticas. Observaram-se índices de gravidez superiores entre as adolescentes com epilepsia em comparação às controles (p<.0001). Não houve diferença na freqüência de aborto entre as adolescentes com epilepsia. Neste estudo, as adolescentes com epilepsia apresentaram comportamento e função sexual similares às adolescentes sem doenças crônicas. Embora a função gonadal destas pacientes estivesse preservada, os distúrbios menstruais foram significantes, sugerindo que estas adolescentes possam estar em um processo em evolução com ciclos anovulatórios e disfunção reprodutora na vida adulta. Portanto, os aspectos relacionados à função e comportamento sexual, contracepção e função gonadal, em adolescentes com epilepsia, requerem atenção especial por parte dos profissionais de saúde. / It is known that in women with epilepsy, the epileptic syndrome, seizure frequency and antiepileptic drugs may act on sexual function, sexual behavior and reproductive function. Several factors have been associated with these changes such as: duration and severity of the epilepsy, kind of antiepileptic drug and locality of the epileptogenic lesion. Based on knowledge acquired with studies in women, it is assumed that female adolescents suffer similar influences. This study aimed to evaluate several aspects related to sexual function, to sexual behavior, to sexual education and to gonadal function in female adolescents with epilepsy. We prospectively studied 35 females, with ages between 10 and 20 years, with active partial and generalized epilepsies and epileptic syndromes classified according to ILAE criteria (1989). Criteria of exclusion were: patients that had not yet had their menarche, those in use of hormonal contraceptives or intrauterine devices, either at the moment of the evaluation or in the last three months; patients with previous gynecological surgery or endocrine disorders; patients with associated chronic disease or moderate to severe mental deficiency that might hinder completion of the study protocol. Information on sexual function and education were obtained with a standard questionnaire. Our study protocol for gonadal function included analysis of the following criteria: regular menstrual cycles, dysmenorrhea, hormonal levels (FSH, LH, stradiol, progesterone, prolactin, testosterone, T3, free T4, TSH), pelvic ultrasound study, and recent or ongoing pregnancy. Gonadal function was considered normal when at least one of the above parameters was found to be adequate. No significant differences were observed between age at first sexual intercourse (p=0.54), sexual activity (p=0.23), libido (p=1,00) and orgasm (p=0.23) among patients with epilepsy, when compared to controls. Sexually active adolescents reported the use of contraceptives, although only 20.1% with orientation done by a health professional. Age of menarche was similar in both groups, but the use of valproate close to menarche and frequent seizures were factors that anticipated this event. Moreover, adolescents with epilepsy presented irregular menstrual cycles more frequently than controls. Menstrual irregularity was correlated to the presence of tonic-clonic generalized seizures (p=0.02), regardless the epilepsy type or syndrome, and with longer disease duration (p=0.06), despite of seizure frequency. Higher rates of pregnancy were observed in adolescents with epilepsy compared to controls (p<.0001). Abortion rates were similar in both groups. In this study, adolescents with epilepsy presented sexual function and behavior similar to their peers without chronic diseases. Although the gonadal function of these patients was spared, menstrual disorders were significant, suggesting that these adolescents may be in an ongoing process with anovulatory cycles and reproductive dysfunction in later adulthood. Therefore, aspects related to sexual behavior and function, contraception and gonadal function in adolescents with epilepsy require special attention by health professionals.
580

Avaliação do estado nutricional e da fertilidade do solo na cultura do plátano (Musa AAB subgrupo Plátano cv. Hárton). / Evaluation of the nutritional status and of the soil fertility for the plantain crop (Musa AAB subgroup plantain cv. Hárton).

Perez, Vianel de Jesus Rodriguez 26 June 2003 (has links)
Este trabalho teve o objetivo de propor uma metodologia adequada ao diagnostico nutricional e à avaliação da fertilidade do solo, dentro do contexto do balanço nutricional da cultura do plátano (Musa AAB subgrupo plátano cv. Hárton) no Sul do Lago do Maracaibo, Venezuela. O procedimento inicial foi, estratificar a área de amostragem por series semelhantes de solos da região. Desta maneira, selecionaram-se quatro lavouras com um histórico de melhor rendimento, na serie de solos de texturas francas. Em seguida fez-se a amostragem completamente ao acaso, entre os meses de julho a dezembro dos anos 2000 e 2001. O tamanho da amostra tirada por lavoura, foi de 30 unidades experimentais. Entretanto, por segurança acrescentaram-se cerca de 25%, dadas as possibilidades de perdas por rajadas de vento e chuva e outros infortúnios. A unidade experimental foi formada pela planta "mãe" e seu broto lateral "filho" em pleno desenvolvimento. Em cada unidade coletou-se a amostra foliar, na planta "mãe" de acordo a norma estabelecida pelo Método de Amostragem Internacional de Referencia (MEIR). Concomitantemente, tomou-se a amostra de solo, na faixa de adubação, em frente do "filho" em duas profundidades 0 - 20 cm e 21 - 40 cm. As amostras de folhas foram analisadas para N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Mo e Zn. Nas amostras de solo se determinou-se pH, condutividade elétrica, matéria orgânica, areia, silte, argila, P, K, Ca, Mg, S, B, Cu, Fe, Mn e Zn. Os dados foram avaliados por analises de regressão com as combinações lineares dos componentes principais, regressão múltipla e obtenção da media aritmética das plantas com maior rendimento. Os resultados demonstraram que o modelo de regressão das combinações lineares com o rendimento deu uma melhor avaliação e predição do rendimento do plátano Hárton, dentro do contexto do balanço nutricional. Com esse modelo, posteriormente estimou-se o rendimento e se separou a população em classes desde o menor até o maior rendimento. Observaram-se nos dados dos analises de solos e folhas, incrementos, decréscimos ou ausência da variação nas concentrações de nutrientes em relação com o rendimento. Isto permitiu realizar interpretações simultâneas das análises de solos e folhas sem a necessidade de valores de referência. Por conseguinte vê-se que o modelo de regressão do rendimento com as combinações lineares vai além do uso de valores de referência isolados, pois permitiu determinar e utilizar o balanço nutricional entre todas as variáveis estudadas. Os resultados assim obtidos, permitem que a metodologia utilizada, seja indicada como una proposta de interpretação dos resultados de análises de solos e folhas. / The aim of this work is to suggest an adequate methodology for the evaluation of the nutritional status and of the fertility of soil for plantain grown in the South of Lake Maracaibo, Venezuela. Initially the area to sample was split into similar soil series. Four high yielding plantations were selected within a soil series of intermediate texture. Afterwards a random sampling was carried out from July to December 2000 and 2001. The sample per plantation had 30 experimental units, plus 25 % for safety reasons, since losses could occur due to weather conditions and other adverse factors. The experimental unit consisted of the "mother" plant and its fully developed "daughter". In each unit leaf sampling was done according to the "Method of International Sampling for Reference"(MEIR). Soil Samples were colleted in front of he daughter in the fertilization band at the depths of 0-20 and 21-40 cm. Leaf samples were analysed for N, P, K, Ca, Mg, S, B, Cu, Fe, Mn, Mo and Zn. pH, conductivity, organic matter, sand, silt, clay, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn were determined in the soil samples. Data were evaluated by regression analysis with the lineal combinations of the main components, and by multiple regression. Results have shown that the regression model of the lineal combination with yield gave a better evaluation and prediction of the plantain crop, within the context of nutritional balance. This, on its turn allowed for the assessment of yield and for the separation of the population in yield classes. It was possible to observe both in the soils and leaves concentrations of nutrients related and not related to yield. It was possible, therefore, to conduct simultaneous interpretation of soil and leaf analyses obviating the need for reference values. The model of regression of yield against lineal combinations goes farther the than the isolated reference values since it allowed for the determination and utilization of nutritional balance among all variables. This methodology could be proposed for the interpretation of the results of soil and plant analyses.

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