• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1745
  • 1264
  • 459
  • 395
  • 185
  • 124
  • 61
  • 60
  • 49
  • 44
  • 36
  • 32
  • 27
  • 27
  • 27
  • Tagged with
  • 5465
  • 1170
  • 799
  • 683
  • 672
  • 443
  • 440
  • 440
  • 394
  • 365
  • 355
  • 316
  • 311
  • 290
  • 272
  • 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.
71

Martial satisfication among pre-marital cohabiting couples and non pre-marital cohabiting couples

Ormsby, Stephani L. 01 July 2007 (has links)
This study examined whether a difference in marital satisfaction existed among pre-marital cohabitating couples and non pre-marital cohabitating couples. Twenty of the couples had cohabitated and twenty had never cohabitated prior to their marriage. The forty couples were from the Atlanta metropolitan and LaGrange, Georgia areas and were selected for the study utilizing a non probability/purposive snowball sampling technique. The couples were referred by previous participants and were screened in order to ensure that all eligibility requirements were met. The couples' ages ranged from 20-45 years and all couples were involved in their first marriage. The Marital Satisfaction Inventory Revised (MSI-R) was administered to all forty couples in order to ascertain differences in marital satisfaction and to determine an interaction effect of gender and cohabitation status. The MSI-R is a 150 question, true-false inventory which measures marital satisfaction by testing nine marital scales and two validity scales. The findings of the study indicated that there were significant differences in marital satisfaction among premarital cohabitating and non pre-marital cohabitating husbands and wives. The significance between the two groups were Aggression, Family History of Distress, Time Together, Role Orientation, and Disagreement about Finances.
72

Formování sestřihových snRNP v buněčném jádře / Formování sestřihových snRNP v buněčném jádře

Novotný, Ivan January 2011 (has links)
1 ABSTRACT There are many structures, suborganelles and bodies in the eukaryotic cell nucleus. These domains provide the nucleus with many specific functions. Nucleolus is specialized compartment serves to ribosomes assembly, nuclear speckles or Splicing Factors Compartment play an important role in RNA processing and best studied of them, Cajal bodies (CBs), are involved in snRNP maturation. However, non-membrane substructures are not unique for cell nucleus; processing bodies (P bodies) found in the cytoplasm are proposed to be important places in mRNA degradation pathway. This work is a compilation of four projects focused on non-membrane cellular bodies; namely, nuclear CBs and cytoplasmic P bodies. Both CBs and P bodies are dynamic structures that continuously exchange their components with surrounding environment. In addition to a widely accepted role of CBs in snRNP biogenesis, we show that the CB serves as a place where snRNPs are regenerated after each round of splicing. Thus, CBs are important nuclear compartment involved in snRNP recycling. To further characterize tri-snRNP assembly in CBs we applied kinetic experiments combined with mathematical modeling and created a kinetic model of tri- snRNP formation in the CB that determined kinetic parameters of tri-snRNP formation. Moreover, our kinetic...
73

Regulace pre-mRNA sestřihu v prostředí buněčného jádra / Regulace pre-mRNA sestřihu v prostředí buněčného jádra

Hnilicová, Jarmila January 2011 (has links)
Eukaryotic genes contain non-coding sequences - introns that are removed during pre-mRNA splicing by the spliceosome. The spliceosome is composed of five snRNPs (U1, U2, U4/U6 and U5) which assemble on pre-mRNA in a step-wise manner and together with additional non-snRNP proteins catalyse splicing. Mutations in splicing factors can cause severe diseases, for example a point missense mutation (called AD29) in hPrp31 (U4/U6 snRNP specific protein) induces retinitis pigmentosa, disease often leading to complete blindness. In this PhD thesis we show that the hPrp31 AD29 mutant is unstable and is not properly incorporated into spliceosomal snRNPs. In addition, the expression of the mutant protein reduces cell proliferation, which indicates that it interferes with cellular metabolism (likely splicing) and could explain the induction of retinitis pigmentosa. Next, we focus on a role of nuclear environment in pre-mRNA splicing. It was shown that new U4/U6·U5 snRNPs are preferentially assembled in non-membrane nuclear structure - Cajal body. Here we expand this finding and provide evidence that Cajal bodies are also important for U4/U6·U5 snRNP recycling after splicing. In addition, we analyzed a role of chromatin and particularly histone acetylation modulates in splicing regulation. Using inhibitor of...
74

Pre-equalization for pre-Rake MISO DS-UWB systems

Torabi, Elham 05 1900 (has links)
In recent years, ultra-wideband (UWB) communications has gained tremendous popularity in both research community and industry. The large bandwidth of UWB systems raises new wireless channel effects and consequently unique advantages as well as challenges to be dealt with, compared to conventional wireless systems. One of these advantages is the ability to resolve dense multipath components and use Rake combining at the receiver in order to significantly reduce the negative effects of fading. However, implementing a Rake receiver with a sufficiently large number of fingers to make use of this advantage is an evident challenge for most UWB devices with limited signal processing capabilities. A possible approach to overcome this problem is to move computational complexity from the receiver to the more powerful transmitter, which is the main focus of the present work. In this thesis, we propose two novel pre-equalization schemes for multiple- input single-output (MISO) direct-sequence ultra-wideband (DS-UWB) systems with pre-Rake combining and symbol-by-symbol detection. The first pre-equalization filter (PEF) scheme employs one PEF per transmit antenna, whereas in the second, simplified PEF (S-PEF) scheme all transmit antennas share the same PEF. For both schemes the optimum finite impulse response (FIR) and infinite impulse response (IIR) PEFs are calculated based on the minimum mean squared error (MMSE) criterion. We show that in contrast to previously proposed schemes for DS-UWB, both our proposed PEF schemes efficiently exploit the channel shortening properties of the pre-Rake filter. In particular, our proposed PEF schemes operate at the symbol level. We also show that under certain conditions the S-PEF scheme achieves the same performance as the more complex PEF scheme. Finally, we demonstrate that a single-input multiple-output (SIMO) DS-UWB system with post-Rake combining and MMSE post-equalization is the dual system to the considered MISO DS–UWB system with pre-Rake combining and MMSE pre-equalization. This uplink-downlink duality can be exploited for efficient calculation of the PEFs and for complexity reduction. Our simulation results show that the proposed PEF schemes achieve significant performance gains over pre-Rake combining without equalization even if only short PEFs are employed, and this is the case even for long UWB channel impulse responses.
75

Pre-equalization for pre-Rake MISO DS-UWB systems

Torabi, Elham 05 1900 (has links)
In recent years, ultra-wideband (UWB) communications has gained tremendous popularity in both research community and industry. The large bandwidth of UWB systems raises new wireless channel effects and consequently unique advantages as well as challenges to be dealt with, compared to conventional wireless systems. One of these advantages is the ability to resolve dense multipath components and use Rake combining at the receiver in order to significantly reduce the negative effects of fading. However, implementing a Rake receiver with a sufficiently large number of fingers to make use of this advantage is an evident challenge for most UWB devices with limited signal processing capabilities. A possible approach to overcome this problem is to move computational complexity from the receiver to the more powerful transmitter, which is the main focus of the present work. In this thesis, we propose two novel pre-equalization schemes for multiple- input single-output (MISO) direct-sequence ultra-wideband (DS-UWB) systems with pre-Rake combining and symbol-by-symbol detection. The first pre-equalization filter (PEF) scheme employs one PEF per transmit antenna, whereas in the second, simplified PEF (S-PEF) scheme all transmit antennas share the same PEF. For both schemes the optimum finite impulse response (FIR) and infinite impulse response (IIR) PEFs are calculated based on the minimum mean squared error (MMSE) criterion. We show that in contrast to previously proposed schemes for DS-UWB, both our proposed PEF schemes efficiently exploit the channel shortening properties of the pre-Rake filter. In particular, our proposed PEF schemes operate at the symbol level. We also show that under certain conditions the S-PEF scheme achieves the same performance as the more complex PEF scheme. Finally, we demonstrate that a single-input multiple-output (SIMO) DS-UWB system with post-Rake combining and MMSE post-equalization is the dual system to the considered MISO DS–UWB system with pre-Rake combining and MMSE pre-equalization. This uplink-downlink duality can be exploited for efficient calculation of the PEFs and for complexity reduction. Our simulation results show that the proposed PEF schemes achieve significant performance gains over pre-Rake combining without equalization even if only short PEFs are employed, and this is the case even for long UWB channel impulse responses.
76

Adding Agency to Art: The Pre-Raphaelites, Their Wives, and The Intersection of Art and Victorian Gender Norms

Pompetti, Claire 01 January 2014 (has links)
This thesis deals with the intersection of art and Victorian gender. The first chapter will deal with the Victorian era in England from the 1840s to 1900s. This chapter will serve as background information to familiarize the reader with Victorian London, the birth place of the Pre-Raphaelites. By examining the subject of industrialization in England and seeing how it changed and influenced society as a whole, the Pre-Raphaelites’ motives for formation become evident and their artistic style is understood in context. The next chapter takes a close look at the art that the Pre-Raphaelites were producing, examining both its subject matter and its literary basis in comparison to the historical setting. By using art as historical evidence, it shows the Pre-Raphaelites’ own personal investment in the subject of Victorian gender relations. Finally, the third chapter examines the wives of the Pre-Raphaelites as a case study for how these real Victorian woman acted and behaved, outside of the expectations and social constraints of the era. Since these were the women most closely associated with the Pre-Raphaelites and their lives were generally well-documented, they make excellent subjects to follow to determine what sort of agency they had in comparison to their stereotypes and male counterparts. Overall, this thesis seeks to tie together the ideas of Victorian gender norms and Pre-Raphaelite art to create a more nuanced and complete history of the Pre-Raphaelites as people and artists.
77

O desenvolvimento da preocupação materna primaria em primiparas com pre-eclampsia : estudo clinico-qualitativo / The development of the primary maternal preoccupation in primiparous womwn with pre-eclampsia : clinical qualitative study

Fleury, Camila, 1975- 14 August 2018 (has links)
Orientadores: Maria Yolanda Makuch, Mary Angela Parpinelli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-14T02:44:34Z (GMT). No. of bitstreams: 1 Fleury_Camila.pdf: 1750197 bytes, checksum: ecab1a83258efefc9d0f99a995c1c71f (MD5) Previous issue date: 2009 / Resumo: Objetivo: Estudar as vivências e o desenvolvimento da preocupação materna primária de mulheres primíparas diagnosticadas com pré-eclâmpsia. Método: Como marco conceitual para compreender a relação mãe-filho utilizou-se o conceito preocupação materna primária desenvolvido por Winnicott. Foi realizado um estudo clínico-qualitativo. A construção da amostra foi feita por amostragem proposital de homogeneidade ampla, seguindo-se o critério de saturação de informação para a definição do número de participantes. Foram conduzidas entrevistas semidirigidas, utilizando-se um roteiro temático. Todas as entrevistas foram gravadas e transcritas na íntegra. Para a saturação dos dados foi utilizado o referencial teórico sobre a preocupação materna primária. Os dados foram analisados por meio da técnica de análise de conteúdo temática. Resultados: Participaram deste estudo 15 mulheres. O diagnóstico de PE foi uma surpresa para as mulheres, pois até então sua gravidez se desenvolvia sem problemas. Todas as mulheres relataram ter dificuldade para compreender o significado da doença e os episódios de internação. As participantes se referiram a vivências de angústia, solidão, tristeza e ansiedade; e algumas a sentimentos de culpa. A maioria das mulheres teve medo de que seu bebê pudesse morrer ou nascer com complicações ocasionadas por sua doença. O momento do parto foi sentido como um evento repentino e inesperado para as mulheres, distanciando-se de suas fantasias e expectativas e aumentando os sentimentos de falta de controle sobre a situação e medo. Todas relataram que não planejam ter mais filhos, devido ao receio de passarem novamente pela mesma situação. Observou-se nos relatos das participantes que o relacionamento com suas próprias mães influenciou o desenvolvimento de seu papel materno. O apoio da família, principalmente do parceiro, durante a gravidez, parto e puerpério, foi percebido como importante e facilitou a dedicação das mulheres às necessidades do bebê. O apoio dado pela equipe médica também foi sentido como importante. Todas as participantes deste estudo mostraram sinais do desenvolvimento da preocupação materna primária. Durante a gestação já referiam uma aproximação afetiva com o filho, que se manteve e se fortaleceu no puerpério. Na fala das mulheres observou-se o prazer em prestar os cuidados ao bebê, com uma facilidade para interpretar e compreender suas necessidades, além de uma abdicação dos interesses pessoais para se dedicar a esse filho. Conclusão: Mulheres primíparas diagnosticadas com PE, com bebês saudáveis e que permaneceram em contato com elas, sentiram o impacto da doença em suas vidas. Contudo, revelaram-se aptas ao desenvolvimento da preocupação materna primária / Abstract: Objective: Study the life experience of primiparous women diagnosed with pre-eclampsia (PE) and the development of primary maternal preoccupation. Methods: a clinical-qualitative study was performed. Women were selected by purposive sampling of broad homogeneity and the number of participants was determined following the criteria of information saturation. Semi-structured interviews were conducted using a thematic guide. All interviews were recorded and verbatim transcribed. For data analysis Winnicott theoretical concepts regarding the primary maternal preoccupation were used. Furthermore, data was analyzed through the thematic contents analysis technique. Results: A total of 15 women participated in the study. The diagnoses of PE was a surprise to participants because their pregnancy had been without problems. All women had difficulties to understand the meaning of the illness in their lives and of the episodes of hospitalization. Women referred to feelings of anguish, loneliness, sadness and anxiety, in some cases feelings of guilt. Most women felt fear that their baby might die or be born with complication because of their illness. All interviewed women referred that they did not plan on having more children due to the fear of going through the process again. Childbirth was felt as a sudden and unexpected event, different from their expectations and increased their feelings of lack of control and fear. The relationship of the participants with their mothers was related to the development of mother-child relationship. Family support, mainly of their partner during pregnancy, delivery and postpartum, was perceived as important and facilitated their dedication to babies necessities. The support given by health professionals was also perceived as important. All participants had developed signs of primary maternal preoccupation. During pregnancy emotional closeness was observed and this persisted and increased after the baby was born. These women had pleasure in taking care of their babies, were able to recognize and understand their babies' needs and abdicated their own needs and interests to be devoted to their babies. Conclusion: The results of this study show that primiparous woman with diagnosis of PE, whose babies were born healthy and remained with them during postpartum hospitalization, even though they felt the impact of their illness were able to develop a primary maternal preoccupation / Universidade Estadual de Campi / Ciencias Medicas / Mestre em Tocoginecologia
78

Mapping Pre-Service Teacher Talk: Variations in Talk About Mathematics, Ability, and Themselves as Mathematical Learners

Tracy, Jacob Dennis, Tracy, Jacob Dennis January 2017 (has links)
It has been argued that teachers do not always teach in the ways their teacher education programs promoted. One cause of this problem has to do with teachers' conceptions about mathematics and ability being incompatible with the visions of mathematics that teacher educators promote. For example, teacher educators may emphasize the need for conceptual understanding but a teacher who equates understanding with being correct and fast will enact this goal differently from someone who expects students to be able to explain and communicate their understanding. The way a teacher understands what it means to do mathematics and be good at mathematics will influence their future teaching. Furthermore, the messages teachers send to their students about who they are as mathematical learners are full of messages about what it means to do and be good at mathematics. Additionally, these messages can have a long-term impact on how those students view themselves and the decisions they make for their future. This study uses qualitative methods to better understand pre-service teacher (PST) talk, how their talk relates, and how their talk changes over time. I describe PST talk as it relates to mathematics (M), ability (A), and themselves as mathematical learners (P) (the three components of the MAP framework). This study took place with the PSTs in two sections of a mathematical content course for elementary school teachers taught by the researcher. First, using grounded theory, I developed codes to understand how these PSTs talked in regards to the three components and applied these codes to written reflections at the beginning and end of our course. After analyzing the data I selected and interviewed 14 PSTs one year after our course. Again, I applied the same codes to their talk in the interview to see how their talk continued to change. Select interview PSTs were then chosen to represent common and uncommon examples of PST talk. Findings from this study show that talk across the MAP framework was related and that this talk became more standards-aligned by the end of the content course. However, the findings also provide a much more nuanced insight into different relationships and changes in talk. One finding shows that when variations in PST talk existed between framework components it was most commonly due to PSTs talking about mathematics in a more traditional way than when they talked about ability or themselves as mathematical learners. Another finding shows that during the interviews (one year after our course) PSTs continued to talk about themselves and abilities in mostly standards-aligned ways but reverted towards more traditional talk when discussing mathematics and how someone demonstrates their mathematical understanding. These findings have important implications for future research and for teacher educators. First, the relationships between the components of the MAP framework suggest that addressing PSTs conceptions of mathematics and their conceptions of ability may affect how they talk about individuals as mathematical learners. Second, the findings show which aspects in the MAP framework PSTs more readily talk about in standards-aligned ways. This provides insights into which areas teacher educators may want to emphasize more in trying to promote changes in PST talk. Lastly, these findings also show which aspects of PST talk maintain over a longer time frame and which aspects need a greater sustained emphasis. All of this is necessary as we support PSTs to think and talk about mathematics and mathematical abilities in standards-aligned ways that are truly supportive of all students.
79

Pre-equalization for pre-Rake MISO DS-UWB systems

Torabi, Elham 05 1900 (has links)
In recent years, ultra-wideband (UWB) communications has gained tremendous popularity in both research community and industry. The large bandwidth of UWB systems raises new wireless channel effects and consequently unique advantages as well as challenges to be dealt with, compared to conventional wireless systems. One of these advantages is the ability to resolve dense multipath components and use Rake combining at the receiver in order to significantly reduce the negative effects of fading. However, implementing a Rake receiver with a sufficiently large number of fingers to make use of this advantage is an evident challenge for most UWB devices with limited signal processing capabilities. A possible approach to overcome this problem is to move computational complexity from the receiver to the more powerful transmitter, which is the main focus of the present work. In this thesis, we propose two novel pre-equalization schemes for multiple- input single-output (MISO) direct-sequence ultra-wideband (DS-UWB) systems with pre-Rake combining and symbol-by-symbol detection. The first pre-equalization filter (PEF) scheme employs one PEF per transmit antenna, whereas in the second, simplified PEF (S-PEF) scheme all transmit antennas share the same PEF. For both schemes the optimum finite impulse response (FIR) and infinite impulse response (IIR) PEFs are calculated based on the minimum mean squared error (MMSE) criterion. We show that in contrast to previously proposed schemes for DS-UWB, both our proposed PEF schemes efficiently exploit the channel shortening properties of the pre-Rake filter. In particular, our proposed PEF schemes operate at the symbol level. We also show that under certain conditions the S-PEF scheme achieves the same performance as the more complex PEF scheme. Finally, we demonstrate that a single-input multiple-output (SIMO) DS-UWB system with post-Rake combining and MMSE post-equalization is the dual system to the considered MISO DS–UWB system with pre-Rake combining and MMSE pre-equalization. This uplink-downlink duality can be exploited for efficient calculation of the PEFs and for complexity reduction. Our simulation results show that the proposed PEF schemes achieve significant performance gains over pre-Rake combining without equalization even if only short PEFs are employed, and this is the case even for long UWB channel impulse responses. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate
80

Interakce proteinů Prp22 a Prp45 ve spliceosomu pučící kvasinky / The interaction of Prp22 and Prp45 proteins in budding yeast spliceosome

Senohrábková, Lenka January 2010 (has links)
Protein Prp22 is a DEAH box RNA helicase, which plays two distinct roles in pre-mRNA splicing: it participates in second transesterification step (ATP independent function) and it releases mature mRNA from the spliceosome (ATP dependent function). Prp45p, yeast ortholog of the human transcription co-regulator SNW/SKIP, is an essential splicing factor, it is included in spliceosome throughout the splicing reaction. Mutant prp45(1-169) genetically interacts with some alleles of NTC complex and second step splicing factors, one of them is also gene PRP22. Here we present, that mutants prp22(-158T) and prp22(-327A), which are synthetically lethal with prp45(1-169), express lower amount of Prp22p due to the mutation in upstream regulation region. Mutants prp22(-158T), prp22(300PPI) and prp22(-327A) affect splicing of pre-mRNA with mutation in 5'ss with respect to sequence of the second exon. N-terminal mutants prp22(∆301) and prp22(∆350) are synthetically lethal with prp45(1-169). Synthetic lethality is possibly caused by lower efficiency of Prp22 recruitment to the spliceosomes, which is no more viable for cells.

Page generated in 0.0652 seconds