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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.
361

Characterisation of Nespas, a non-coding imprinted RNA

Ottway, Charlotte Jane January 2010 (has links)
Nespas is the non-coding antisense transcript of the imprinted Gnas cluster; it is expressed from the paternal allele and is located on mouse distal chromosome 2. In this thesis new transcripts of >10 kb and 0.8 kb have been identified. The 0.8 kb transcript is a spliced variant that is retained in the nucleus and its 3’ end lies approximately 30 kb from the start site. Transcription from the Nespas promoter does not proceed beyond this point. A collection of previously known splice variants have also been detected and are exported to the cytoplasm. Nespas is expressed in the embryo during the second half of gestation and peaks at 13.5 dpc. Nespas is imprinted in the placenta at 11.5, 15.5 and 17.5 dpc. The Nespastm4Jop allele, to truncate the Nespas transcript 10.5 kb from the start site, has been transmitted through the germline and a breeding colony established. Preliminary analysis shows Nespas has a regulatory function. A second targeting construct to truncate Nespas 12.5 kb from the start site has been designed and assembled to investigate whether the 3’ end of the Nespas transcript that is transcribed upstream of the Nesp promoter is required for Nespas-mediated silencing of Nesp.
362

Attention and Functional Connectivity in Survivors of Childhood Brain Tumors

Fox, Michelle E. 12 May 2017 (has links)
To study potential hyperactivity and hyperconnectivity based on the latent resource hypothesis, this study assessed functional connectivity in survivors of childhood brain tumors compared to their healthy peers during an attention task using psychophysiological interaction (PPI) analyses and evaluated for a relationship with performance. Twenty-three survivors and 23 healthy controls completed a letter n-back task in the scanner. An empirically-based seed was placed in the parietal lobe, a theoretical seed was placed in the hippocampus, and a control seed was placed in the occipital lobe. Differences in both performance and functional connectivity networks from each seed emerged between groups, with some findings supporting the latent resource hypothesis and other networks showing compensatory function in survivors. Attention networks, phonological networks, and executive function networks were all found to differ between controls and survivors.
363

Long-Term Outcomes of Prolonged Exposure and Naltrexone for Patients with Comorbid Posttraumatic Stress Disorder and Alcohol Dependence

Avny, Shelley 01 January 2014 (has links)
A growing body of research is examining effective treatment(s) for individuals with comorbid posttraumatic stress disorder (PTSD) and alcohol dependence (AD). However, treatments for this comorbid population have been inadequately studied in the longer term. This study represents a long-term follow-up assessment of a randomized controlled trial that compared combined therapy (prolonged exposure + naltrexone) with monotherapies (prolonged exposure or naltrexone) for patients with PTSD and AD (see Foa, Yusko, McLean et al., 2013). Attempts were made to contact 120 participants 5-10 years after the original trial to assess the maintenance of treatment gains. Nineteen individuals were located and agreed to participate. A series of mixed ANCOVAs were conducted with PTSD symptom severity and percentage of days drinking and heavy drinking as the dependent variables. Findings revealed that reductions in PTSD symptoms and drinking behaviors generally were maintained 5-10 years after treatment. There was some relapse in heavy drinking days, and combination treatment was most effective for long-term PTSD outcomes. Challenges of conducting follow-up research with this population, implications and limitations of the present findings, and directions for future research are discussed.
364

Studie populace kalouse ušatého (Asio otus) na zimovišti v Kladně / Monitoring of the Long-eared Owl (Asio otus) Population at the Town of Kladno Wintering Place

Ponikelská, Eliška January 2015 (has links)
My thesis deals with the study of the population of the Long-eared Owl (Asio otus) on a wintering place in Kladno - Kročehlavy. I mention numbers, arrivals and departures of the Long-eared Owl during the years 2013-2015 and the influence of abiotic factors on these results. I also deal with ringing and recoveries of these owls in the territory of Kladno. I verify the hypothesis of the influence of warm weather, rainfall and snow cover on the representation of small mammals and birds species in the diet of the Long-eared Owl in this thesis. In addition, my thesis is devoted to the analysis of methodology and species identification in food of the Long-eared Owl by skulls and pelvic bones. In my thesis, when determining the type of small mammals I deal with sexing of Common Vole (Microtus arvalis) and Wood Mouse (Apodemus sylvaticus) of the pelvic bones. According to bone fragments of the pelvis dominant representation of male Common Voles and Wood Mouse in a certain period of winter was investigated. On the basis of the obtained results I have compiled charts and tables and I have compared them with previous research from the years 2006 - 2012 in the same study area in Kladno - Kročehlavy. Keywords: Long-eared Owl (Asio otus), diet, weather, Common Vole (Microtus arvalis), Wood Mouse (Apodemus...
365

Závislost výkonů ve vybraných atletických disciplínách žáků druhého stupně ZŠ / Dependence of performance in selected athletic disciplines students in second level primary schools

Vopršálek, Radek January 2016 (has links)
NAME: Determine the dependence of performance in selected athletic disciplines students in primary schools AUTHOR: Radek Vopršálek DEPARTMENT: Katedra tělesné výchovy SUPERVISOR: PhDr. PaedDr. Ladislav Kašpar, Ph.D. ABSTRACT: The aim of this thesis is to explore the relationship and dependency between performances in chosen sports disciplines for pupils of primary school. The disciplines I have chosen to determine the relative performance are: long jump and 60 meters sprint. In the theoretical part there is a description and analysis of these sports disciplines. In the practical part there is a measurement of pupils' performances in that two sports disciplines and creating a dependency relationship between them. KEYWORDS: Long jump, Bounce, Run, Relationship.
366

Analýza dvouleté sportovní přípravy skokanky do dálky / A long jump athlete's two - year training analysis.

Štěpánková, Petra January 2012 (has links)
Title: A long jump athlete's two - year training analysis. Objectives: To assess the athlete's performance progress under the leadership of two different coaches and to evaluate her development over a two - year training period of studies at Faculty of Physical Education and Sport in Prague. Methods: Methods used in the thesis are: observation, description and deduction. Results: Characteristic of long - jump athlete's training activity differed by age categories. The achievements are sorted in tables and graphs. Along with the analysis of the training taken and results achieved, there are comments about health added. The analysis is held in the two - year period under the leadership of two coaches. Selected training indicators as well as the results in several tests are presented in the tables. Keywords: athletics, long jump, training, analysis.
367

Genome-wide identification of non-canonical targets of messenger RNA synthesis and turnover factors in Saccharomyces cerevisiae

Tuck, Alex Charles January 2013 (has links)
Pervasive transcription is widespread amongst eukaryotic genomes, and produces long noncoding RNAs (lncRNAs) in addition to classically annotated transcripts such as messenger RNAs (mRNAs). LncRNAs are heterogeneous in length and map to intergenic regions or overlap with annotated genes. Analogous to mRNAs, lncRNAs are transcribed by RNA polymerase II, regulated by common transcription factors, and possess 5’ caps and perhaps 3’ poly(A) tails. However, lncRNAs perform distinct functions, acting as scaffolds for ribonucleoprotein complexes or directing proteins to nucleic acid targets. The act of transcribing a lncRNA can also affect the local chromatin environment. Furthermore, whereas mRNAs are predominantly turned over in the cytoplasm, both nuclear and cytoplasmic pathways reportedly participate in lncRNA degradation. In this study, I address the question of when and how lncRNAs and mRNAs are distinguished in the cell. Messenger RNAs interact with a defined series of protein factors governing their production, processing and decay, and I hypothesised that lncRNAs might be similarly regulated. I therefore sought to determine which mRNA-binding proteins, if any, also bind lncRNAs. I reasoned that this would reveal the point at which lncRNAs and mRNAs diverge, and how differences in their biogenesis and turnover equip them for different roles. I selected factors from key stages of mRNA metabolism in Saccharomyces cerevisiae, and identified their transcriptome-wide targets using CRAC (crosslinking and analysis of cDNAs). CRAC can detect interactions with low abundance transcripts under physiological conditions, and reveal where within each transcript a protein is bound. Analyses of binding sites in mature mRNAs and intron-containing pre-mRNAs revealed the order in which the tested factors interact with mRNAs, and which region they bind. The poly(A)-binding protein Nab2 bound throughout mRNAs, consistent with an architectural role, whereas the cytoplasmic decay factors Xrn1 and Ski2 bound to poly(A) tails, which might act as hubs to coordinate turnover. The RNA packaging factors Tho2 and Gbp2, and nuclear surveillance factors Mtr4 and Trf4 bound abundantly to intron-containing premRNAs, indicating that they act during or shortly after transcription. The tested factors bound lncRNAs to various extents. LncRNA binding was most abundant for Mtr4 and Trf4, moderate for Tho2, Gbp2, the cap binding complex component Sto1, and the 3’ end processing factors Nab2, Hrp1 and Pab1, and lowest for Xrn1, Ski2 and the export receptor Mex67. This suggests that early events in lncRNA and mRNA biogenesis are similar, but unlike mRNAs, most lncRNAs are retained and degraded in the nucleus. Analyses of two documented classes of lncRNA, cryptic unstable transcripts (CUTs) and stable unannotated transcripts (SUTs), revealed some differences. SUTs were most similar to mRNAs, with canonical cleavage and polyadenylation signals flanking their 3’ ends, and poly(A) tails bound by the poly(A)-binding protein Pab1. CUTs lacked these characteristics, and in comparison to SUTs bound more abundantly to Mtr4 and Trf4 and less so to Ski2, Xrn1 and Mex67. Furthermore, CUTs accumulated upon Hrp1 depletion, suggesting that Hrp1 functions non-canonically to promote CUT turnover. Mtr4, Trf4 and Nab2 also bound abundantly to promoter-proximal RNA fragments generated from ~1000 protein coding genes. These fragments possessed short oligo(A) tails (hallmarks of nuclear surveillance substrates), were not bound to cytoplasmic factors, and apparently correspond to a population of ~150-200 nt promoter-proximal lncRNAs. Notably, CRAC analyses of Mtr4 and Sto1 targets in yeast subjected to a media shift revealed widespread changes in the abundance and surveillance of mRNAs, promoter-proximal transcripts and CUTs, which at many loci were arranged in a complex transcriptional architecture. Overall, the transcriptome-wide binding analyses presented here reveal that lncRNAs diverge from mRNAs prior to export, and are predominantly retained in the nucleus. Transcript fate is apparently determined during 3’ end processing, with CUTs diverging from mRNAs early in transcription via a distinct termination pathway coupled to rapid turnover, and SUTs diverging during or shortly after cleavage and polyadenylation, making them more stable and perhaps prone to escape to the cytoplasm. Promoter-proximal transcripts might arise from termination associated with an early checkpoint in Pol II transcription. The diverse behaviours of lncRNAs arise from their association with distinct subsets of RNA binding proteins, some of which perform different roles when bound to different types of transcript. In conclusion, my results provide the foundation for a mechanistic understanding of how distinct classes of non-coding Pol II transcripts are produced, and how they can perform diverse functions throughout the nucleus.
368

The potential of bast natural fibres as reinforcement for polymeric composite materials in building applications

Węcławski, Bartosz Tomasz January 2015 (has links)
Natural fibre composites (NFCs), which are polymers reinforced with cellulosic bast fibres, have the potential to be applied into a range of building products. They are seen as an alternative to glass fibre reinforced plastics (GFRP) in some applications, because of natural fibres (NF) relatively high strength and low density. Moreover, natural fibres have a set of beneficial traits, such as thermal insulation, thermal stability, biodegradability, and are inherently renewable. Those characteristics are of importance when NF are used as reinforcements in polymer composites, but developments in mechanical performance, reliability and economic viability are still required in order to be adopted fully by industry. The goal of this thesis was the development of a processing methodology for NFC laminate and subsequent material characterisation to assess the developed material suitability for building applications. Research objectives included materials selection, processing route development for laminates and tubes, manufacture of NFC laminates and analysis of mechanical properties in order to find an optimal composition. Hemp and flax fibres were selected as the reinforcement, because both have high mechanical properties and are important bast fibre crops in the European region with established cultivation and processing methods. As a matrix, fossil-fuel based and partially bio-derived thermoset resin systems were used. Handling and processing methodologies were developed for laminates and composite tubes based on filament winding and compression moulding techniques. The effects of the selected factors, namely material composition, volume fraction, processing parameters, reinforcement linear density, yarn twist, lamination sequence, yarn waviness and hybrid hemp-wool reinforcement were subsequently described in mechanical properties analysis of laminates. The influence of weathering conditions on the mechanical performance of the NFCs was examined. Furthermore, a study of NFC tubes under compression was performed. Results showed that the developed laminates reinforced with NF yarns have sufficient mechanical properties to be utilised in sandwich panels and/or tubes. However, a low resistance to moisture-related weathering restricts the developed NFCs for indoor applications.
369

Successful aging conceptualization and long-term care: a comparative content analysis of brochure advertising perspective

John, Nicole L. January 1900 (has links)
Master of Arts / Department of Sociology, Anthropology, and Social Work / Laszlo Kulcsar / This study provided an exploratory qualitative analysis of printed brochures to evaluate the conceptualization of successful aging. Data was collected from a sample of 39 printed brochures derived from Kansas Department on Aging Directory (KDAD) of Adult Care Homes 2009. Content analysis methodology was employed to investigate how these brochures reflect the core elements of successful aging as constructed in the gerontological literature (Rowe and Kahn’s and Baltes and Baltes), as well as compare across the ‘traditional’ and ‘culture-change’ models. Other variables of ‘licensure classification’, ‘residency cost’ and ‘gender’ were explored. An overall perspective indicated several brochures met the core elements of successful aging delineated by the literature. In most cases, these elements showed no significance difference for brochures representing facilities by model types, licensure classifications, residency cost and by the demographic of gender.
370

Population Models with Age and Space Structure / Populationsmodeller med ålder- och rymdstruktur

Karlsson, Anton January 2017 (has links)
In this thesis, basic concepts of populational models are studied from a theoretical point of view, especially the long term behaviours. All models are at least time dependent with additional age structure, spatial structure. The last model which is an extension of the von Foerster equation, is dependent on all o f these structures and have a long-term solution for large values of time. Modeling population is a frequent subject in modern biology. It is hard to create a model that appears as realistic as possible. First one might consider that a population size is governed by the current size of the population, along with rates of how each individual contributes (give birth), so that the population increases. and how frequent an individual dies, causing the population to decrease in size. However these sort of models can only describe the size of population in a shorter span of time.

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