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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.
111

Consumo, desempenho, emissão de metano e características de carcaça de novilhos da raça Canchim recriados a pasto e terminados em confinamento / Intake, performance, methane emission and carcass traits of Canchim steers recreated on pasture and finished in feedlot

Méo Filho, Paulo de 22 March 2017 (has links)
O presente trabalho teve como objetivo avaliar novilhos resultantes da seleção genética de diferentes linhagens da raça Canchim (5/8 Charolês, 3/8 Zebu), recriados a pasto e terminados em confinamento, em relação ao consumo alimentar, desempenho, emissão de metano entérico, características de carcaça e cortes cárneos. O experimento foi desenvolvido na Empresa Brasileira de Pesquisa Agropecuária, unidade Pecuária Sudeste, São Carlos/SP. Foram utilizados 46 novilhos da raça Canchim (15 meses, 291 kg de peso vivo), 13 pertencentes a linhagem antiga, 20 a linhagem nova e 13 provenientes do acasalamento entre estas linhagens. A linhagem antiga é mantida como rebanho fechado desde 1953 e foi formada com base em 53 touros Charoleses importados da França, já a linhagem nova teve origem a partir de 1990 com a utilização de touros Charoleses de diferentes origens (Argentina, Brasil, Estados Unidos, França, Inglaterra), e a partir de 1998, com o acasalamento entre as duas linhagens formou-se a linhagem cruzada. Durante a recria a pasto (165 dias), os animais foram alojados em uma área de pastagem (Panicum maximum cv. Tanzânia), onde o manejo adotado foi o de pastejo rotacionado com lotação variável, para as medidas de desempenho foram executadas pesagens a cada 33 dias, e a mensuração da emissão de metano entérico através da técnica do gás traçador hexafluoreto de enxofre realizada em 12 animais da linhagem antiga e 12 da nova. No período de terminação em confinamento, os animais foram dispostos em 4 baias e receberam alimentação ad libitum durante 105 dias, o ganho de peso foi medido a cada 28 dias e para a mensuração de emissão de metano os mesmos animais avaliados a pasto, tiveram acesso ao sistema automatizado GreenFeed®. No momento do abate, foram coletadas informações sobre o peso de carcaça quente, e após 24 horas de resfriamento em câmara fria, o peso da carcaça fria, do traseiro especial, dianteiro e ponta de agulha e na desossa os pesos individuais dos cortes cárneos comerciais. A linhagem nova mostrou-se superior a antiga no período de recria nas variáveis de ganho médio diário, conversão e eficiência alimentar, não se diferenciando dos cruzados. Durante a terminação em confinamento, foi observado o mesmo em relação ao ganho médio diário, já em relação ao consumo, a linhagem nova e os cruzados apresentaram maiores ingestões de alimento comparados à linhagem antiga, enquanto a conversão alimentar dos animais cruzados apresentou maior valor comparados às das linhagens. Na recria a pasto, para se obter maiores ganhos de peso, melhor conversão alimentar e eficiência alimentar, devem ser utilizados animais resultantes de processos de seleção genética. A seleção genética para características de desempenho produtivo não garante animais com menores emissões de metano em condições de pastejo. Nos animais em fase de terminação em confinamento, o maior ganho de peso, melhor conversão alimentar e melhor acabamento de carcaça são obtidos através da utilização de animais resultantes de processos de seleção genética. O mesmo tipo de seleção para características de desempenho produtivo em confinamento leva a maiores consumos diários de alimento e consequentemente a maiores emissões de metano diárias. / The objective of this study was to evaluate steers resulting from the genetic selection of different Canchim (5/8 Charolais, 3/8 Zebu) lineages, rearing to pasture and finished in feedlot, in relation to feed intake, performance, enteric methane emission, carcass traits and retail cuts. The experiment was carried out at the Brazilian Agricultural Research Corporation (Embrapa), Southeast Livestock, São Carlos / SP. A total of 46 Canchim steers (15 months, 291 kg live weight) were used, 13 from the ancient lineage, 20 from the new lineage and 13 from the mating between these lineages. The ancient lineage is kept as a closed herd since 1953 and was formed by 53 Charolais bulls imported from France. The new lineage originated from 1990 with the use of Charolais bulls from different origins (Argentina, Brazil, the United States, France, England), and from 1998 the crossed lineage was formed with the mating between the two lineages. During grazing (165 days), the animals were housed in an pasture area (Panicum maximum cv. Tanzania), where the management used was rotational grazing with variable stocking, for the performance measures were performed weighing every 33 days, and the measurement of the enteric methane emission through the sulfur hexafluoride tracer gas technique was performed in 12 animals of the ancient and 12 of the new lineage. In feedlot the animals were housed in 4 pens and fed ad libitum for 105 days. The weight gain was measured every 28 days and as for the measurement of methane emission the same animals evaluated on pasture had access to the GreenFeed® automated system. Information on the hot carcass weight was collected at the time of slaughter and after 24 hours of cooling in the cold chamber, the weights of the cold carcass, of the special hind, fore and spare ribs, and the individual weights of the retail cuts in boning. The new lineage was superior to the ancient one in the rearing period in the variables of average daily gain, conversion and feed efficiency, not differing from the animals crossed. During feedlot, it was observed the same in relation to the average daily gain, already in relation to intake, the new lineage and the crossbreeds presented higher feed intakes compared to the ancient lineage while the feed conversion of the crossed animals presented higher value compared with the new and ancient lineages. In pasture recreating, in order to obtain greater weight gains, better feed conversion and feed efficiency, animals resulting from genetic selection processes must be used. Genetic selection for performance traits does not guarantee animals with lower methane emissions under grazing conditions. For feedlot animals, the highest weight gain, better feed conversion and better carcass finishing are obtained through the use of animals resulting from genetic selection processes. The same type of selection for traits of performance in feedlot leads to higher daily feed intake and consequently to higher daily methane emissions.
112

Structural and functional studies of the transcriptional regulator Seb1 in fission yeast

Wittmann, Sina January 2016 (has links)
RNA polymerase II (Pol II) is responsible for the transcription of all protein-coding and some non-coding genes in eukaryotes. Its largest subunit, Rpb1, contains a unique C-terminal domain (CTD) which consists of repeats of the heptad YSPTSPS. It acts as a binding platform for proteins that control the different stages of transcription and their recruitment is regulated mainly by differential phosphorylation of residues contained within the CTD. Previous studies could unveil proteins containing a CTD-interacting domain (CID) as important players that specifically bind to certain phosphorylation types of the CTD. More precisely, they were shown to be important for the last step of transcription, termination. Despite extensive research over the past 30 years, the exact mechanism of how these proteins facilitate the dislodgement of Pol II from the DNA template, still remains unknown. The work presented here contains detailed studies of the CID-containing protein Seb1 from the fission yeast Schizosaccharomyces pombe, revealing an unexpectedly broad role of this protein in transcription termination. In addition to a CID, Seb1 also contains an RNA recognition motif (RRM) which allows direct binding to RNA. Here, I present high-resolution crystal structures of both domains of Seb1. While the CID has a very conserved fold, the RNA binding regions contains an unusual arrangement of a canonical RRM intertwined with a second domain that are both important for RNA binding. Structure-based mutations were introduced and a combination of in vitro and genome-wide in vivo studies uncover Seb1 as an essential player in transcription termination. Importantly, both domains are required to promote the full function of Seb1. Despite its homology to the well-studied budding yeast protein Nrd1, the role of Seb1 in fission yeast is quite different. This thesis therefore provides important insight into the mechanisms that underlie eukaryotic transcription termination.
113

Zánik nájmu bytu / Termination of flat lease

Jaša, Jaromír January 2012 (has links)
This thesis deals with termination of flat lease. The main aim of this thesis was to focus on particular ways by which lease of flat terminates. Significant part of the thesis is devoted to termination of flat lease by notice, which is relatively in detail defined on Act. No. 40/1964 Col., the Civil Code. The Supreme court's decisions are published in the thesis very often, because these decisions take irretrievable place in the field of termination of flat lease. The thesis contains also short discourse about several questions concerning termination of flat lease.
114

Rates and Predictors of Adolescent Premature Termination: Applying Clinically Significant Change

Bullock, Mariah Meaalii 01 March 2017 (has links)
Premature termination from child and adolescent psychotherapy is a prevalent problem for clients, their families, and mental health services. Rates of premature termination have been estimated at a range of 16-72%. Many variables have been examined as potential predictors of premature termination, yielding inconsistent conclusions. Researchers propose that part of this variability in rates and predictors is due to the inconsistent application of definitions of premature termination. The past literature identifies two main categories of definitions in this line of research: therapist judgment and number of sessions. This study aims to incorporate a relatively new definition, clinically significant change, in the evaluation of premature termination rates and predictor variables in a sample of adolescents receiving treatment in three community mental health clinics. Results showed that 65.7% of the participants were classified as premature terminators under the definition of clinically significant change. Premature termination was significantly correlated with parenting skills and ratings of the therapeutic alliance by both the parent and adolescent. However, the only variable that predicted PT was the therapeutic alliance as rated by the adolescent. It appears that, rather than having a small range of rates and universal predictors of premature termination, it may depend on the definition that is chosen.
115

A Comparison of the Safety and Efficacy of Three Medical Abortion Protocols

Perera, Dhammika 01 January 2019 (has links)
Unsafe abortions pose serious threats to women's health. Medical abortion provides safer abortion access to many. The lengthy interval between misoprostol and mifepristone creates multiple barriers for women and providers. A paucity of research exists about medical abortion protocols that allow single day procedures. The efficacy and the safety of 3 medical abortion protocols of varying lengths were explored in this study. A secondary data set of over 55,000 patients from the United Kingdom was retrospectively analyzed using binomial logistic regression. Efficacy results showed no significant difference between the conventional and the simultaneous protocols; when compared to those, the 6- to 8- hour protocol showed a 79% higher risk (OR = 0.210, 95% CI = 0.178 - 0.246) of failure. Safety of the simultaneous protocol was 48% lesser (OR = 0.524, 95% CI = 0.447 - 0.613) and the safety of the 6- to 8- hour protocol 61% lesser (OR = 0.386, 95% CI = 0.304- 0.489) compared to the conventional protocol. The absolute risk of complications or severe adverse events of all protocols (0.98%, 1.97%, and 2.67%) was very low. The results suggest the simultaneous protocol is a viable alternative to the conventional protocol up to 10 weeks' gestation. The results could promote the adoption of the simultaneous protocol by health systems, give millions more women access to safe and effective single day medical abortions, reduce the need for skilled clinicians, and reduce cost burdens for both women and for healthcare systems overall. Implementation of these social changes could make abortion safer globally.
116

The challenges that affect midwives in termination of pregnancy at Bohlabela District in Limpopo Province

Mayimele, N S January 2007 (has links)
Thesis (MDEV) --University of Limpopo, 2007. / The study sought to develop guidelines that are aimed at improving Termination of Pregnancy (TOP) services that are rendered by public hospital based midwives. The researcher applied a qualitative and descriptive design. The study targeted midwives in the Bohlabela District, which has three hospitals. A non-probability purposive sampling was used to 6 midwives who are currently conducting TOP services in the hospitals. Data collection was both in-depth and conducted in face-to-face interviews with each participant. The findings of the study were analyzed, categorized into sub-themes, and revealed that midwives who conduct TOP services experience the following challenges, namely: inadequate human resource, poor infrastructure, lack of equipments, poor management support, and lack of support from doctors. Based on the findings of the study, it is imperative that all hospitals be designated centres for TOP services, so as to reduce the workload in the few hospitals that currently are inundated. The infrastructure needs to be improved, information about TOP services to the public has to be disseminated through awareness campaigns, and scarce skills allowances must be introduced. In addition, more staff members need to be employed. The study further recommends that the TOP policy guideline be reviewed in terms of allowing other competent health professionals to perform TOP. Chapter two discusses the literature review regarding the challenges that affect midwives who conduct TOP. In this study, theresearch compares the practice of TOP by the developing and developed countries, looks at related to laws at on TOP; gives an overview of sterilization Act in South Africa; mentions the amendments of laws on TOP; considers other legal restrictions; presents mandatory counseling for TOP clients; focuses on religious, cultural and traditional beliefs. The researcher has consulted different literatures, journals articles and website on challenges that affect midwives in rendering TOP in Limpopo, South Africa and world wild. Chapter three presents research methodology that consists of research design; area of study; population; sampling method; data collection method and procedure; ensuring trust worthiness; and ethical consideration, to be followed by limitation of the study. Chapter deals with data analysis and interpretation. Chapter five presents the researcher’s conclusions and recommendations. / Not listed
117

Determinants of attitudes towards termination of pregnancy among learners in the Mankweng and Seshego Townships of Polokwane, South Africa

Madiba, Makgabo Frangeline January 2013 (has links)
Thesis (MA. (Clinical Psychology)) -- University of Limpopo, 2013 / The current study aimed at investigating the relationship between attitudes towards termination of pregnancy (TOP) and family structure and functioning, religiosity, and death anxiety. Participants of this study consisted of 330 school-going, adolescent, female participants aged 12 to 19 years. The results indicated that no relationship exists between attitudes towards TOP and the type of family structure from which an individual stems. The relationship between attitudes towards TOP and the Family Assessment Device (FAD) general family functioning scale did not reach statistical significance either. When attitudes towards TOP were correlated with the more specific family functioning subscales, the FAD problem-solving subscale was negatively associated with attitudes towards TOP. Additionally, the relationship between attitudes towards TOP and death anxiety was not statistically significant. However, analysis indicated that there is a statistically significant, negative relationship between attitudes towards TOP and intrinsic religiosity among school-going adolescents. Final analysis involved the regression of variables of FAD problem-solving and intrinsic religiosity on attitudes towards TOP. Both intrinsic religiosity and FAD problem-solving scores were predictors of attitudes towards TOP.
118

Retention of Conservation Acquired by Instructional Methods, Eight Months After Termination of Instruction

Waite, Wenden W. 01 May 1969 (has links)
This study attempted to determine if subjects that had been instructed in the principle of conservation, maintained conservation after termination of instructions. Using subjects from kindergarten to third grade that had received instructions by use of both concrete example and mental imagery methods. Those S's that received instructions were compared with S's that had received no instructions. A test of conservation was administered to a total of 96 S's approximately eight months after termination of instructions to determine if the scores received on a test of those students that had received instructions exceeded those S's that had not received instructions. A statistical analysis of the data indicated that instructions were of no value to kindergarten or first grade students , but that second grade students showed a significant improvement in their ability to conserve after receiving instructions and the third grade group achieved the competence on test performance as their peers that had exceeded them before instructions were given. The results thus would indicate that instructions could be valuable in acquiring conservation if the S's have reached a certain cronological or maturational level in his development.
119

Motherhood or abortion: Pregnancy resolution decisions of Australian teenagers

Evans, Ann, ann.evans@anu.edu.au January 2001 (has links)
Australia has a lower teenage fertility rate than other industrialised English-speaking countries. However, with over 11,000 births and 12,000 abortions to teenagers each year, the resolution of teenage pregnancy is an issue faced by many young Australian women. ¶ This research seeks to explore the factors that discriminate between those who terminate and those who continue a teenage pregnancy. To achieve this aim a survey was conducted on young ever-pregnant women throughout New South Wales and the Australian Capital Territory. The survey sought information on young women’s characteristics on three different levels: individual; institutional; and societal or cultural. ¶ The findings suggest that, at each of the three levels proposed, there are factors that discriminate between young women who choose abortion and those who choose motherhood. At the individual level, attitudes to abortion and career aspirations were found to affect pregnancy resolution. At the institutional level factors relating to education, family, relationships and religion were found to discriminate between the two groups. Finally, at the cultural level, ethnicity and area of residence were found to be associated with pregnancy resolution, in addition to modifying the effect of characteristics at other levels.
120

Computer simulations of ribosome reactions

Trobro, Stefan January 2008 (has links)
<p>Peptide bond formation and translational termination on the ribosome have been simulated by molecular mechanics, free energy perturbation, empirical valence bond (MD/FEP/EVB) and automated docking methods. Recent X-ray crystallographic data is used here to calculate the entire free energy surface for the system complete with substrates, ribosomal groups, solvent molecules and ions. A reaction mechanism for peptide bond formation emerges that is found to be catalyzed by the ribosome, in agreement with kinetic data and activation entropy measurements. The results show a water mediated network of hydrogen bonds, capable of reducing the reorganization energy during peptidyl transfer. The predicted hydrogen bonds and the structure of the active site were later confirmed by new X-ray structures with proper transition states analogs. </p><p>Elongation termination on the ribosome is triggered by binding of a release factor (RF) protein followed by rapid release of the nascent peptide. The structure of the RF, bound to the ribosomal peptidyl transfer center (PTC), has not been resolved in atomic detail. Nor is the mechanism known, by which the hydrolysis proceeds. Using automated docking of a hepta-peptide RF fragment, containing the highly conserved GGQ motif, we identified a conformation capable of catalyzing peptide hydrolysis. The MD/FEP/EVB calculations also reproduce the slow spontaneous release when RF is absent, and rationalize available mutational data. The network of hydrogen bonds, the active site structure, and the reaction mechanism are found to be very similar for both peptidyl transfer and termination. </p><p>New structural data, placing a ribosomal protein (L27) in the PTC, motivated additional MD/FEP/EVB simulations to determine the effect of this protein on peptidyl transfer. The simulations predict that the protein N terminus interacts with the A-site substrate in a way that promotes binding. The catalytic effect of L27 in the ribosome, however, is shown to be marginal and it therefore seems valid to view the PTC as a ribozyme. Simulations with the model substrate puromycin (Pmn) predicts that protonation of the N terminus can reduce the rate of peptidyl transfer. This could explain the different pH-rate profiles measured for Pmn, compared to other substrates.</p>

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