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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.
581

Is the Family Size of Parents and Children Still Related? Revisiting the Cross-Generational Relationship Over the Last Century

Beaujouan, Eva, Solaz, Anne 04 1900 (has links) (PDF)
In most developed countries, the fertility levels of parents and children are positively correlated. This article analyzes the strength of the intergenerational transmission of family size over the last century, including a focus on this reproduction in large and small families. Using the large-scale French Family Survey (2011), we show a weak but significant correlation of approximately 0.12-0.15, which is comparable with levels in other Western countries. It is stronger for women than men, with a gender convergence across cohorts. A decrease in intergenerational transmission is observed across birth cohorts regardless of whether socioeconomic factors are controlled, supporting the idea that the family of origin has lost implicit and explicit influence on fertility choices. As parents were adopting the two-child family norm, the number of siblings lost its importance for having two children, but it continues to explain lower parity and, above all, three-child families. This suggests that the third child has increasingly become an "extra child" (beyond the norm) favored by people from large families.
582

Mecanismo da redução de fertilidade em Aedes aegypti infectados por Plasmodium gallinaceum. / Mechanism of fecundity reduction in Aedes aegypti infected by Plasmodium gallinaceum.

Ioshino, Rafaella Sayuri 29 April 2013 (has links)
O objetivo do estudo foi confirmar se a redução da fecundidade dos mosquitos Aedes aegypti infectados por Plasmodium gallinaceum ocorre por morte das células foliculares dos ovários. Mosquitos infectados produzem menos ovos quando comparado aos mosquitos sadios. Uma explicação é a redução da viabilidade celular que ocorre nos ovários de fêmeas 18, 22 e 24 horas após o repasto sanguíneo infectado (RSI) como foi observado pela técnica MTT. Utilizando o acridine orange, não foi possível observar a morte das células foliculares no intervalo de 18 horas, mas 22 e 24 horas após o RSI essas células estão em morte em relação ao mesmo intervalo do repasto sanguíneo controle (RSC). A análise do DNA fragmentado foi realizada através do TUNEL. Ovários de 22 e 24 horas após RSC e RSI foram negativos nas regiões dos cortes histológicos examinados. Sendo assim, podemos concluir que, utilizando esses ensaios foi possível identificar a morte das células foliculares como uma resposta a redução da fecundidade, porém não foi possível determinar que o tipo de morte é apoptose. / The objective of this study was to confirm the hypothesis that the fertility reduction in Plasmodium gallinaceum-infected Aedes aegypti occurs by follicular cells death. A significant reduction in the number of eggs laid by infected mosquitoes was confirmed. It was observed a reduction of viable cells in 18, 22 and 24 hours PBM infected by MTT assay. It was not possible to observe cell death in ovary tissue 18 hours PBM infected, but the follicular cells showed orange color 22 and 24 hours indicating they are in death in relation to the same interval of PBM control. To determine if these cells exhibit apoptosis, we use the TUNEL which mark the fragmented DNA, a characteristic of the apoptosis process. Ovaries 22 and 24 hours PBM infected and control were negative for TUNEL marker from ovary histological preparations. Thus, we conclude that fecundity reduction occurs as a response to follicular cells death caused by P. gallinaceum infection but it was not possible to affirm if the type of follicular cells death is apoptosis.
583

Some aspects of the effect of gossypol on antifertility.

January 1990 (has links)
by Ng, Shuet Fai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1990. / Bibliography: leaves 118-137. / ACKNOWLEDGEMENTS --- p.i / ABSTRACT --- p.ii / CONTENTS --- p.iv / Chapter CHAPTER 1: --- GENERAL INTRODUCTION / Chapter I. --- The History of Gossypol --- p..4 / Chapter II. --- The Chemistry of Gossypol --- p..7 / Chapter A. --- Enantiomers of Gossypol --- p.10 / Chapter B. --- Analysis of Gossypol --- p.11 / Chapter III. --- Metabolism and Distribution of Gossypol in Body --- p.12 / Chapter IV. --- The Effect of Gossypol --- p.14 / Chapter A. --- Effect of Gossypol on Different Animal Species --- p.14 / Chapter B. --- Effect of Gossypol on Male Reproductive Organs --- p.16 / Chapter 1. --- Testis and Epididymis --- p.16 / Chapter 2. --- Spermatozoa and Spermatogenic Cells --- p.18 / Chapter C. --- Effect of Gossypol on Reproductive Hormones --- p.20 / Chapter D. --- Effect of Gossypol on Enzymes --- p.22 / Chapter 1. --- Enzymes in Capacitation --- p.23 / Chapter 2. --- The Metabolic Enzymes --- p.24 / Chapter a. --- On Glycolysis --- p.24 / Chapter b. --- On TCA Cycle --- p.26 / Chapter c. --- On Oxidative Phosphorylation --- p.26 / Chapter 3. --- Adenyl Cyclase --- p.26 / Chapter 4. --- Na+/K+-ATPase --- p.28 / Chapter E. --- Other Effects of Gossypol --- p.29 / Chapter V. --- Toxicity of Gossypol --- p.30 / Chapter A. --- General Toxic Effect --- p.30 / Chapter B. --- The Mutagenicity --- p.32 / Chapter VI. --- Clinical Trials of Gossypol --- p.33 / Chapter VII. --- The Purpose of This Study --- p.35 / Chapter A. --- Gossypol and LDH-X --- p.35 / Chapter B. --- Effect of Gossypol on Antioxidant Defense Systems / Chapter C. --- The Influence of Gossypol on Zinc Metabolism --- p.37 / Chapter CHAPTER 2: --- EFFECT OF GOSSYPOL ON LDH-X OF COCK AND DRAKE / Chapter I. --- Introduction --- p.39 / Chapter A. --- General Description of Lactate Dehydrogenase --- p.39 / Chapter B. --- Discovery of LDH-X --- p.40 / Chapter C. --- Properties of LDH-X --- p.41 / Chapter D. --- Role of LDH-X in the Spermatozoa --- p.42 / Chapter E. --- Gossypol and LDH-X --- p.43 / Chapter II. --- Materials and Methods --- p.44 / Chapter A. --- Reagents --- p.45 / Chapter B. --- Methods --- p.45 / Chapter 1. --- The Effect of Gossypol on the Spermatozoa of Cock and Drake --- p.45 / Chapter 2. --- "Measurement of LDH-X Activities in Cock, Drake, Mouse and Rat" --- p.46 / Chapter a. --- Preparation of Samples --- p.46 / Chapter b. --- Enzyme Assay --- p.47 / Chapter III. --- Results / Chapter A. --- Effect of Gossypol on the Spermatozoa of Cock and Drake --- p.48 / Chapter 1. --- Cock --- p.48 / Chapter 2. --- Drake --- p.49 / Chapter B. --- "The LDH-X Activities of Cock, Drake, Rat and Mouse" --- p.51 / Chapter IV. --- Discussion --- p.54 / Chapter CHAPTER 3: --- "THE EFFECT OF GOSSYPOL ON THE METABOLISM OF ZINC IN THE TESTIS, HAIR AND RETINA OF HAMSTER AND MOUSE" / Chapter I. --- Introduction --- p.57 / Chapter A. --- The Physiological Role of Zinc in Animals --- p.57 / Chapter B. --- The Relationship Between Gossypol and Divalentions --- p.58 / Chapter II. --- Materials and Methods --- p.60 / Chapter A. --- Reagents --- p.60 / Chapter B. --- Treatment of Animals for the Zinc Content Study / Chapter 1. --- Detection of Zinc Content in Hamster Hair --- p.61 / Chapter 2. --- "Detection of Zinc Distribution in the Hair, Testis, and Retina in Hamster and Mouse" --- p.62 / Chapter C. --- Determination of Zinc and Iron --- p.63 / Chapter III. --- Results --- p.63 / Chapter A. --- Amount of Zinc in Hamster's Hair --- p.63 / Chapter B. --- "The Distribution of Zinc Content in Hair, Testis and Retina of Hamster and Mouse" --- p.69 / Chapter IV. --- Discussion --- p.71 / Chapter CHAPTER 4: --- EFFECT OF GOSSYPOL ON THE ANTIOXIDANT DEFENSE SYSTEM IN THE TESTIS OF HAMSTER / Chapter I. --- Introduction --- p.73 / Chapter A. --- Oxygen Radicals in Living Cells --- p.75 / Chapter B. --- Oxygen Damage of Spermatozoa --- p.76 / Chapter C. --- Antioxidant Defense System --- p.77 / Chapter 1. --- Enzymatic Antioxidants --- p.78 / Chapter 2. --- Non-Enzymatic Antioxidants --- p.78 / Chapter II. --- Materials and Methods --- p.81 / Chapter A. --- Reagents --- p.81 / Chapter B. --- Experimental Animals --- p.82 / Chapter C. --- The Effect of Scavengers on the Antifertility of Gossypol --- p.83 / Chapter 1. --- Vitamin C --- p.83 / Chapter 2. --- Selenium --- p.84 / Chapter 3. --- Vitamin E --- p.85 / Chapter D. --- Chemical Interaction of Gossypol with Vitamin C and Sodium Selenite --- p.85 / Chapter E. --- Malonaldehyde Assay --- p.85 / Chapter F. --- The Effect of Gossypol on the Antioxidant Defense Enzymes --- p.86 / Chapter 1. --- Drug Treatment --- p.86 / Chapter 2. --- Preparation of Samples for Enzyme Determination --- p.87 / Chapter 3. --- Enzyme Assays --- p.87 / Chapter a. --- Se-GSH-Px --- p.88 / Chapter b. --- Glutathione-S-Transf erase --- p.88 / Chapter c. --- Catalase --- p.89 / Chapter d. --- Superoxide Dismutase --- p.90 / Chapter III. --- Results --- p.90 / Chapter A. --- The Effect of Scavengers on the Antifertility of Gossypol --- p.90 / Chapter B. --- Chemical Interaction of Gossypol with Vitamin C and sodium selenite --- p.91 / Chapter C. --- The MDA Concentration of the Testis of Hamster after Gossypol and Scavengers Injection --- p.101 / Chapter D. --- The Antioxidant Defense Enzymes --- p.101 / Chapter IV. --- Discussion --- p.109 / Chapter CHAPTER 5: --- CONCLUSION AND GENERAL DISCUSSION --- p.113 / REFERENCES --- p.118 / Chapter APPENDIX I --- THE INFLUENCE OF DIETARY LARD ON THE ANT I FERTILITY EFFECT OF GOSSYPOL --- p.138 / Chapter APPENDIX II --- PROTOCOL FOR GOSSYPOL DETERMINATION --- p.158
584

Papel do zinco sobe a fertilidade e função testicular de ratos expostos ao tabaco /

Garcia, Patrícia Carvalho. January 2009 (has links)
Orientador: Oduvaldo Câmara Marques Pereira / Banca: Eliana Milanesi Rubio / Banca: Débora Cristina Damasceno / Banca: Daniela Cristina Ceccatto Gerardin / Banca: Fernanda Klein Marcondes / Resumo: Aproximadamente um terço da população mundial é tabagista. Devido ao fato de ser um carcinógeno que causa mutações nas células somáticas, o tabaco pode afetar a saúde reprodutiva masculina. No homem o tabagismo é um fator de risco para o desenvolvimento de diversas enfermidades urológicas, embora o mecanismo exato de atuação seja ainda desconhecido. Por outro lado, ao analisarmos os aspectos reprodutivos, verificamos que o zinco é essencial para a espermatogênese como um co-fator de metaloenzimas envolvidas na transcrição do DNA, na expressão dos receptores esteróides e na síntese protéica, bem como apresenta ação anti-oxidante e anti-apoptótica. Com base nestas informações, o objetivo do presente trabalho consistiu em analisar o papel do zinco sobre a fertilidade e função testicular de ratos expostos ao tabaco. Ratos Wistar com 60 dias de idade (n=10/grupo) foram divididos em quatro grupos G1 (grupo controle), G2 (expostos a fumaça do tabaco-20 cigarros/dia), G3 (grupo controle suplementado com zinco-20mg/Kg cloreto de zinco diariamente por gavagem) e G4 (expostos a fumaça do tabaco e suplementados com zinco). A duração do tratamento foi de oito semanas. Ao final do experimento foram avaliados os seguintes parâmetros: massa corporal, peso úmido dos órgãos da reprodução e da glândula adrenal, concentração plasmática de testosterona, função testicular (análise seminal e produção diária de espermatozóides), fertilidade e comportamento sexual. As respostas farmacológicas da musculatura lisa genital acessória masculina (vesícula seminal e ducto deferente) a drogas autonômicas e danos no DNA do espermatozóide foram também avaliados. Os resultados foram comparados entre si pela análise de variância não-paramétrica, para modelo com dois fatores, complementada com teste de comparações múltiplas de Tukey, p<0,05... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: About one-third of the world's male population smokes tobacco daily. Considering the larger number of men worldwide who smoke, and that cigarette is a known somatic cells mutagen and carcinogen, there is a major concern that smoking may adversely affect male reproductive health. For men the smoking is a risk factor for the development of a variety of urological diseases, although the exact mechanism of action is still unknown. Furthermore, when we look at the reproductive issues, we found that zinc is essential for spermatogenesis as a cofactor of metalloenzyme involved in the transcription of DNA, the expression of steroid receptors and protein synthesis. In addition, zinc presents anti-oxidant and anti-apoptotic actions. Based on this information, the purpose of this study was to examine the role of zinc on fertility and testicular function in rats exposed to tobacco. Male Wistar rats were divided into four groups (10/group): Control (G1), Cigarette smoke (G2), Zinc (G3: Zn 20mg/kgdaily by gavages) and Zinc/cigarette (G4). The treatment was applied during eight weeks. After finishing the treatment, the following parameters were analyzed: body weight, wet weight of the reproductive organs and the adrenal gland; plasma testosterone concentration, testicular function (seminal analysis and daily production of spermatozoa); fertility and sexual behavior. The pharmacological responses of male accessory genital smooth muscle (vas deferens and seminal vesicle) to autonomic drugs and DNA damage in the spermatozoa were also evaluated. The results were compared by non-parametric analysis of variance, for model with two factors, and the test for multiple comparisons of Tukey was applied when necessary , p<0.05. The exposure to cigarette smoke decreased the concentration of testosterone parallel to a decrease in the concentration, morphology, and motility of spermatozoa. As a result of these... (Complete abstract click electronic access below) / Doutor
585

Completeness of birth registration in Brazil: an overview of methods and data sources

Lima, Everton E. C., Queiroz, Bernardo Lanza, Zeman, Krystof January 2018 (has links) (PDF)
We provide an analysis of the main sources of data used to estimate fertility schedules in developing countries, giving special attention to Brazil. In addition to the brief history of various data sources, we present several indirect demographic methods, commonly used to estimate fertility and assess the quality of data. From the methods used, the Synthetic Relational Gompertz model gives the most robust estimates of fertility, independent of the data source considered. We conclude that different demographic data sources and methods generate differing estimates of fertility and that the country should invest in quality of birth statistics.
586

Caracterização das subpopulações e atributos espermáticos como método preditivo de desempenho na produção in vitro de embriões em bovinos / Characterization of subpopulations and spermatic features as a predictive method of performance in the in vitro production of embryos in cattle

Luana de Cássia Bicudo 24 August 2018 (has links)
A predição do desempenho de touros na produção in vitro de embriões (PIVE), pela avaliação seminal, não está plenamente estabelecida. Com este estudo, objetivou-se caracterizar as diferenças nos atributos espermáticos de touros com baixo e alto desempenho, baseado nas taxas de clivagem e de blastocisto, visando estabelecer métodos preditivos de maior eficiência na PIVE. A partir do histórico de três anos da empresa In Vitro Brasil&reg;, foram selecionados touros que haviam resultado nas menores e maiores taxas de clivagem e de blastocisto, estabelecendo-se 4 grupos experimentais: baixa taxa de clivagem (BC, n=5), alta taxa de clivagem (AC, n=5), baixa taxa de blastocisto (BB, n=5) e alta taxa de blastocisto (AB, n=5). Foram adquiridas palhetas de sêmen congelado dos touros de cada grupo, nas quais foram avaliados, antes (Pré-Percoll&reg;) e após centrifugação em gradiente de Percoll&reg; (Pós-Percoll&reg;), os atributos espermáticos: cinética, em sistema CASA; integridade de membranas plasmática e acrossomal (FITC-PSA/PI), potencial de membrana mitocondrial (JC-1), status oxidativo (DHE, CellROXTM green/PI, MitoSox red), apoptose (FITC-FMK-VAD/PI) e DNA (SCSA), por citometria de fluxo; morfologia; atividade mitocondrial (DAB); capacitação (CTC); teste funcional e TBARS induzido. Diferenças entre grupos (BC vs. AC e BB vs. AB) foram estimadas pelo teste t. Para todas as análises estatísticas foi considerado nível de significância de 5%. Na ausência de interações significativas, o efeito dos grupos foi analisado ao fundir os momentos Pré e Pós-Percoll&reg;. Os grupos AC e AB apresentaram valores superiores de VAP, VCL, ALH e DNC e valores inferiores de BCF, STR, LIN e WOB, cinética indicativa de hiperativação. Adicionalmente, estes grupos apresentaram indícios de menor ocorrência de estresse oxidativo, evidenciados pelo percentual de espermatozoides com membrana lesada e estresse oxidativo (CellROXTM green/PI) no grupo AC e nível de DHE no grupo AB. Para os demais atributos estudados, não se obteve diferença entre os grupos. Por meio de análise de regressão logística multivariada, constatou-se que a taxa de clivagem sofre efeito de: VCL, BCF e percentual de espermatozoides com integridade de membrana e sem estresse oxidativo; já a taxa de blastocisto, sofre efeito de: defeitos menores, VSL, DABIII e DHE, os quais foram inclusos nos respectivos modelos preditivos. As taxas obtidas com o modelo preditivo foram comparadas às taxas reais por análise de correlação de Pearson, que resultaram em intensidade moderada tanto para clivagem (r=0,56) quanto para blastocisto (r=0,44). Subpopulações espermáticas com diferentes perfis de cinética em CASA, foram determinadas em três etapas estatísticas segundo Núñez-Martínez et al. (2006). Foram detectadas 4 subpopulações: 1-Rápidos e progressivos; 2- Hiperativados; 3- Lentos e sinuosos; 4- Lentos e progressivos. Touros com alto desempenho (AC e AB) apresentaram maior percentual de subpopulação 2, Pré-Percoll&reg;, e das subpopulações 1 e 2, Pós-Percoll&reg;. Com isto, demonstra-se ser possível diferenciar touros de baixo e alto desempenho na PIVE, pela avaliação dos atributos espermáticos, com o estabelecimento de modelos preditivos para as taxas de clivagem e de blastocisto. Ademais, o estudo das subpopulações espermáticas constitui-se no método mais efetivo para a predição do desempenho in vitro. / The prediction of bull performance on the in vitro production (IVP) of bovine embryos, by the seminal evaluation, is not fully established. Thus, the aim of this study was to characterize the differences in the sperm features of bulls with low and high performance, based on cleavage and blastocyst rates, in order to establish predictive methods for a greater efficiency in the IVP. Based on the results obtained in three years from the company In Vitro Brasil&reg;, bulls were selected by the lowest and highest cleavage and blastocyst rates, establishing 4 experimental groups: low cleavage rate (BC, n=5), high cleavage rate (AC, n=5), low blastocyst rate (BB, n=5) and high blastocyst rate (AB, n=5). Frozen semen were obtained from the bulls of each group, in which were evaluated, before (Pre-Percoll&reg;) and after Percoll&reg; gradient centrifugation (Post-Percoll&reg;), the sperm features: kinetics, in CASA; integrity of plasma and acrosomal membranes (FITC-PSA/PI), mitochondrial membrane potential (JC-1), oxidative status (DHE, CellROXTM green/PI, MitoSox red), apoptosis (FITC-FMK-VAD/PI) and DNA (SCSA), by flow cytometry; morphology; mitochondrial activity (DAB); capacitation (CTC); functional test and induced TBARS. Differences between groups (BC vs. AC and BB vs. AB) were estimated by t test. A significance level of 5% was considered for all statistical analysis. In the absence of significant interactions, the effect of the groups was analyzed by merging the moments Pre and Post-Percoll&reg;. The AC and AB groups presented higher values of VAP, VCL, ALH and DNC and lower values of BCF, STR, LIN and WOB, kinetics indicative of hyperactivation. In addition, these groups showed less evidence of oxidative stress, observed by the percentage of spermatozoa with damaged membrane and oxidative stress (CellROXTM green/PI) in the AC group and level of DHE in the AB group. For the others sperm features, there was no difference between groups. By multivariate logistic regression analysis, it was verified that the cleavage rate is affected by: VSL, BCF and percentage of spermatozoa with membrane integrity and without oxidative stress; and the blastocyst rate, is affected by: minor defects, VSL, DABIII and DHE, which were included in the respective predictive models. The rates obtained with the predictive model were compared to the real rates by Pearson correlation analysis, which resulted in moderate intensity for both cleavage (r=0.56) and blastocyst (r=0.44). Spermatic subpopulations with different kinetic profiles at CASA were determined in three statistical steps according to Núñez-Martínez et al. (2006). Four subpopulations were detected: 1-Fast and progressive; 2- Hyperactivated; 3- Slow and sinuous; 4- Slow and progressive. Bulls with high performance (AC and AB) presented higher percentage of subpopulation 2, Pre-Percoll&reg;, and subpopulations 1 and 2, Post-Percoll&reg;. In summary, it is possible to differentiate low and high-performance bulls at IVP by evaluating the sperm features, with the establishment of predictive models for the cleavage and blastocyst rates. Furthermore, the study of sperm subpopulations is the most effective method for predicting in vitro performance.
587

The effect of cervical intraepithelial neoplasia and treatment surgeries on fecundability

Klann, Alexandra 24 October 2018 (has links)
INTRODUCTION: Approximately 6 million couples in the United States experience infertility. Because few risk factors for infertility are known, identification of modifiable determinants is an important public health goal. Cervical intraepithelial neoplasia, CIN, occurs when the surface cells of the cervical tissue begin to change, and is caused by infection with a high-risk type of human Papillomavirus (HPV). CIN may affect the cervix’s immunological function, resulting in changes in mucus production, reduced protection against infections, and alterations in sperm transport through the cervical canal. CIN can also progress to invasive cervical cancer. There are four main CIN treatment procedures that aim to remove pre-cancerous cells from the cervix; loop excisions, commonly known as electrosurgical excision procedure (LEEP) or large loop excision of the transformative zone (LLETZ); cryosurgery; conization; and laser ablation. Because the goal of these procedures is to remove abnormal cells, healthy cervical cells may inadvertently be removed as well, leading to further changes in cervical mucus production, sperm motility, and reduced protection against infection. Because of the changes to the cervical tissue and its function, CIN and its surgical treatments may affect fecundability. METHODS: We analyzed data from Pregnancy Study Online (PRESTO), a preconception cohort of 5,594 North American pregnancy planners enrolled and followed between 2013 and 2018. At baseline, participants reported whether they had abnormal Pap tests and their age at their first abnormal Pap test, as well as cervical procedures and their age at the procedure. We estimated fecundability ratios (FR) and 95% confidence intervals (CI) using proportional probabilities models adjusted for sociodemographics, smoking, number of sexual partners, history of sexually transmitted infections/ pelvic inflammatory disease, and HPV vaccination. RESULTS: A history of abnormal Pap test, which we used as a proxy for cervical dysplasia, was positively associated with current and past smoking, gravidity, parity, irregular menses, number of sexual partners, history of chlamydia, genital warts and herpes, as well as a history of pelvic inflammatory disease. Of the women with an abnormal Pap test, the average age at first abnormal Pap test was 23.0 (std=4.5) years and the average number of abnormal Pap tests was 2.1 (std=1.7). We found little association overall between a history of abnormal Pap test and fecundability (FR=1.03, 95% CI: 0.96, 1.11). The results did not differ when the data were examined by number of abnormal Pap tests, or type of procedure. There was also little association between time since the diagnosis or procedure and pregnancy attempt and fecundability. There was however a slight decrease in fecundability within the first 2 years of diagnosis/ procedure, with FRs that tended to increase with increasing time since diagnosis/procedure. DISCUSSION: We found little association overall between a history of abnormal Pap test or cervical dysplasia, including excisional surgeries, and fecundability. These results are consistent with most other studies demonstrating no clear adverse effects of CIN and treatments. Recency of diagnosis or procedure did not appreciably affect these findings. Although we found a very slight decrease in fecundability within the first two years since diagnosis or procedure, fecundability became similar to that of undiagnosed/untreated women after 2 years, and then increased slightly. CONCLUSION: We found little association between a history of abnormal Pap and CIN treatments and fecundability. A major limitation of our study is that the data were self-reported, which may have resulted in non-differential exposure misclassification.
588

Efeito do biocarvão sobre o comportamento da matéria orgânica e do fósforo em solo degradado /

Morales, Marina Moura, 1981- January 2010 (has links)
Resumo: Suprir a demanda de alimento para mais de 6 bilhões de pessoas promovendo agricultura de forma sustentável é o desafio do novo milênio. O biocarvão (BC), ingrediente que proporciona ao solo capacidade de reter matéria orgânica e nutrientes, pode ser uma ferramenta de grande importância na busca de soluções para esse desafio. Portanto, entender o efeito do BC sobre o comportamento da matéria orgânica (MO) e o ciclo do fósforo inorgânico (Pi) em solo degradado foram os objetivos deste trabalho. A taxa de mineralização e o teor de carbono total foram monitorados nas misturas de solo degradado + 35%BC + doses de MO iguais a 0, 10, 40, 70 e 100 t ha-1, nos tempos 0, 80, 160, 240 e 320 dias de incubação em estufa. Reações de sorção e dessorção de Pi foram avaliadas nas misturas de solo degradado + 35%BC + doses de P com 0, 75, 150, 200 e 300 mg kg-1, no tempo 240 dias de incubação, além do controle com somente solo, para ambos os estudos. A adição de BC ao solo promoveu a mineralização da mistura; entretanto, o BC apresentou tendência à recalcitrância ao longo do período, dobrou o tempo de reação com o P tanto para as reações de sorção quanto dessorção, diminuiu a sorção de P do solo e dessorveu quantidades ideais para a maioria das culturas. O BC possui poder fertilizante, porém sua utilização deve ser assistida por possuir características químicas limitantes como pH e sais. Palavras chave: Fertilidade do solo, sorção, dessorção, mineralização. / Abstract: To supply the food demand for more than 6 billion people, promoting sustainable agriculture is the chellenge for the new milennium; the biochar (BC) ingredient that provides the ability to retain soil organic matter and nutrients can be an important tool to figure oout solutions for this challenge, thus, understand the effect of BC on the organic matter (OM) behavior and at inorganic phosphorus (Pi) cycle in degraded tropical soil has been our goal. The mineralization rate and total carbon content were monitored in mixtures of degraded tropical soil + 35% BC + OM doses, equal to 0, 10, 40, 70 and 100 t ha-1 at 0, 80, 160, 240, and 320 greenhouse incubation days. Pi Sorption and desorption Reactions were analysed in mixtures of degraded tropical soil + 35% BC + P rates of 0, 75, 150, 200, 300 mg kg-1, on 240 days of greenhouse incubation, beyond the control with soil by itself. The BC soil addition promote mineralization, however presented recalcitrance tendency in the incubation time, doubled the time of reaction with P for both the reactions of sorption and desorption, decreased P sorption and desorption of soil quantities ideal for most crops. The BC can act as a fertilizer, but its dosage should be well attended as it has the capacity to increase soil pH and salt. / Orientador: Iraê Amaral Guerrini / Coorientador: Nicholas Brain Comerford / Banca: Leonardo Theodoro Büll / Banca: Dirceu Maximino Fernandes / Banca: Newton Paulo de Souza Falcão / Banca: Rodrigo Domingues Barbosa / Doutor
589

Irrigação e fertirrigação por gotejamento para cana-de-açúcar na presença e ausência de boro

Quintana, Kleber Aloisio [UNESP] 14 April 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:03Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-04-14Bitstream added on 2014-06-13T20:41:11Z : No. of bitstreams: 1 quintana_ka_dr_jabo.pdf: 961976 bytes, checksum: 5138fec1a6fd5743038eb37960a30811 (MD5) / Conduziu-se um experimento a campo com cana-planta no município de Barretos-SP, em local de coordenadas geográficas 20° 36’ 35,65” S, 48° 34’ 4,65” W e altitude de 511 m, entre os anos de 2007-2008, com o intuito de avaliar o efeito da fertirrigação com nitrogênio e potássio na irrigação por gotejamento e adição de boro no plantio, nos parâmetros vegetativos e tecnológicos da cana. Os tratamentos foram avaliados em esquema fatorial 3x2, sendo: T1-sequeiro sem boro; T2-sequeiro com boro; T3-irrigado sem boro; T4-irrigado e com boro; T5-fertirrigado sem boro; T6- fertirrigado e com boro. Para as condições de sequeiro e irrigado, a adubação de plantio foi realizada com dosagem integral dos nutrientes; para a condição fertirrigado, o fósforo e o boro foram aplicados manualmente no plantio e o nitrogênio e o potássio foram aplicados por fertirrigação e parcelados em oito vezes. O plantio foi do tipo fileira dupla no espaçamento de 1,4 m x 0,4 m, sendo a linha gotejadora instalada subsuperficialmente no centro da fileira dupla à profundidade de 0,15 metro. A fertirrigação e a irrigação incrementaram a massa de cana industrial, o comprimento da cana e o teor de sacarose do caldo, e proporcionaram menores teores de açúcares redutores. A fertirrigação proporcionou ainda maior teor de fibra na cana. A adição de boro não afetou os parâmetros analisados / We conducted a field experiment with sugar cane plant in the municipality of Barretos-SP, Brazil, with geographical coordinates 20° 36’ 35,65” S, 48° 34’ 4,65” W and altitude 511 m, during the years 2007-2008, in order to evaluate the effect of drip irrigation, fertigation with nitrogen and potassium and the addition of boron at planting, in vegetative and technologicals measurements of the cane. The treatments were evaluated in a 3x2 factorial arrangement: T1-no irrigated without boron; T2-no irrigated with boron; T3-irrigated and without boron; T4-irrigated and with boron; T5-fertigated and without boron; T6-fertigated and with boron. For the no irrigated and irrigated conditions, the planting manure was carried out with full amount of nutrients; for fertigated condition, phosphorus and boron were applied manually in planting, and nitrogen and potassium by fertigation splited in eight times. The planting was the type double row spaced 1.4 m x 0.4 m, and the line of irrigation installed in a subsurface drip system in the center of double row, in the depth of 0.15 meter. The fertigation and irrigation increased the mass of industrial sugar, length of the cane, the sucrose content of juice, and provided lower levels of reducing sugars. The fertigation provided even greater fiber content in cane. The addition of boron did not affect the analyzed parameters
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The manipulation of progesterone profiles during progesterone + estradiol timed ai protocols in dairy cattle : effects on fertility /

Pereira, Marcos Henrique Colombo, 1986. January 2016 (has links)
Orientador: José Luiz Moraes Vasconcelos / Banca: Lindsay Unno Gimenes / Banca: Ocilon Gomes de Sá Filho / Banca: Ricardo Maria dos Santos / Banca: Ky Pohler / Abstract: Study 01- Our hypothesis was that fertility could be increased in a timed AI (TAI) protocol based on estradiol (E2) and progesterone (P4) by combining GnRH with E2-benzoate at the start of the protocol to increase circulating P4 concentration during preovulatory follicle development and by using two prostaglandin (PGF) treatments at the end to decrease circulating P4 concentration near TAI. Lactating Holstein cows (n = 1,808) were randomly assigned during the cool or hot seasons of the year to receive TAI (d0) following one of three treatments: I. Control: CIDR + 2 mg of E2-benzoate on d -11, PGF on d -4, CIDR withdrawal + 1.0 mg of E2-cypionate on d -2, and TAI on d 0; II. 2PGF: Identical to Control protocol with addition of a second PGF treatment on d -2; III. GnRH: Identical to 2PGF protocol with addition of 100 μg GnRH treatment on d -11. Pregnancy diagnoses were performed d32 and d60 after TAI. The GnRH protocol increased percentage of cows with CL (Control = 56.9%; 2PGF = 55.8%; GnRH = 70.5%) and circulating P4 concentration at PGF (Control = 3.28 ± 0.22; 2PGF = 3.35 ± 0.22; GnRH = 3.70 ± 0.21 ng/mL), compared to Control and 2PGF protocols. The positive effects of GnRH treatment on P/AI were only detected during the cool season (GnRH = 50.9%; 2PGF = 44.2%; Control = 41.0%) and not during the hot season. In addition, the effect of GnRH was only observed in cows with low circulating P4 concentration (<3ng/mL) at the start of the protocol and not in cows that began the protocol with high P4. Further, there was an interaction for presence of CL at PGF with follicle diameter such that cows with a CL at PGF had greater P/AI if they ovulated larger rather than smaller follicles near TAI.Season had major effects on many reproductive measures with cool season greater than hot season in percentage of cows with CL at PGF (62.9 vs. 56.2%), ovulatory follicle diameter (15.7 vs. 14.8 mm), expression of ... / Doutor

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