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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.
491

Gruppchefens arbetsroll : En studie om gruppchefers arbete i en modern organisation

Lundberg, Carl, Troedsson Holm, Adam January 2017 (has links)
The purpose of this study was to create an understanding of how group leaders manage their worktime and what conditions the group leader needs to conduct their work assignments. The research design was a single case study that was performed on a larger corporation´s central warehouse. The data collection consisted of semi structured interviews with six group leaders. Furthermore, an inventory of the worktime was made in which the group leaders themselves estimated their worktime during a month of work. The results showed that the group leaders experienced a lack of time but that the conditions were good for leadership. Progress was promoted and the space of action was big. The time inventory showed that the group leaders’ average work were made of 52 hours. The study discusses the job description, which was too wide and should be focused more towards the group. The conclusion was that the group leaders worked reactively, more assignments should be focused towards the group. The job description needed to be better defined and the groups were too big and there were time constraints which affected the work.
492

Characterization of intra-litter variation on myogenic development and myogenic progenitor cell response to growth promoting stimuli

Vaughn, Mathew Alan January 1900 (has links)
Doctor of Philosophy / Department of Animal Sciences and Industry / John M. Gonzalez / This series of studies focuses on the impact of intra-litter variation on fetal myogenesis, and the ability of porcine progenitor cells to respond to growth promoting stimuli. In study 1, the smallest (SM), median (ME), and largest (LG) male fetuses from each litter were selected for muscle morphometric analysis from gilts at d-60 ± 2 and 95 ± 2 of gestation. On d-60 and 95 of gestation LG fetuses had greater whole muscle cross-sectional area (CSA) than ME and SM fetuses, and ME fetuses had greater whole muscle CSA than SM fetuses. Indicating that SM and ME fetuses are on a delayed trajectory for myogenesis compared to LG fetuses. At d-60 the advanced trajectory of LG compared to ME fetuses was due to increased development of secondary muscle fibers; whereas, the advanced myogenic development of LG and ME fetuses compared to SM fetuses was due to the presence of fewer primary and secondary muscle fibers. At d-95 of gestation the advanced myogenic development of LG and ME was due to increased hypertrophy of secondary muscle fibers. For study 2, porcine fetal myoblasts (PFM) were isolated from SM, ME, and LG fetuses from d-60 ± 2 of gestation fetuses and for study 3, porcine satellite cells (PSC) were isolated from the piglet nearest the average body weight of the litter. Both myogenic cell types were utilized to evaluate effects of porcine plasma on proliferation, differentiation, and indications of protein synthesis. For the proliferation assay, cells were exposed to one of three treatments: high serum which consisted high-glucose Dulbecco's Modified Eagle Medium supplemented with 10% (vol/vol) fetal bovine serum, 2% (vol/vol) porcine serum, 100 U penicillan/mL, 100 µg of strepmycin/mL, and 20 µg of gentamicin/mL (HS), low serum which consisted of HS without 10% FBS (LS), and LS supplemented with 10% (wt/vol) porcine plasma (PP). Treatments for the differentiation and protein synthesis assays consisted of either HS or LS media that either contained porcine plasma at 10% (wt/vol; PPP) or 0% (wt/vol; PPN). The HS-PFM had a greater proliferation rate compared to the LS and PP-PFM, and PP-PFM had a greater proliferation rate compared to LS-PFM. The LG fetuses’ PFM had a reduced proliferation rate compared to SM and ME fetuses’ PFM, which were similar. The PPP-PFM had a decreased myotube diameter compared to PPN-PFM. Small fetuses’ PFM had a greater myotube diameter compared to ME and LG fetuses’ PFM, and ME fetuses’ PFM had a greater myotube diameter compared to LG fetuses’ PFM. The proliferation rate of PP-PSC was decreased compared to the HS- and LS-PSC, and HS-PSC had a greater proliferation rate compared to LS-PSC. The PPP-PSC had greater differentiation capacity and myotube diameter than PPN-PSC. In conjunction these results indicate divergent myogenic development among different fetal sizes within a litter and suggest that porcine plasma supplementation stimulates myogenic progenitor cell activity in an age specific manner.
493

A Bayesian method to improve sampling in weapons testing

Floropoulos, Theodore C. 12 1900 (has links)
Approved for public release; distribution is unlimited / This thesis describes a Bayesian method to determine the number of samples needed to estimate a proportion or probability with 95% confidence when prior bounds are placed on that proportion. It uses the Uniform [a,b] distribution as the prior, and develops a computer program and tables to find the sample size. Tables and examples are also given to compare these results with other approaches for finding sample size. The improvement that can be obtained with this method is fewer samples, and consequently less cost in Weapons Testing is required to meet a desired confidence size for a proportion or probability. / http://archive.org/details/bayesianmethodto00flor / Lieutenant Commander, Hellenic Navy
494

Power and Sample Size for Three-Level Cluster Designs

Cunningham, Tina 05 November 2010 (has links)
Over the past few decades, Cluster Randomized Trials (CRT) have become a design of choice in many research areas. One of the most critical issues in planning a CRT is to ensure that the study design is sensitive enough to capture the intervention effect. The assessment of power and sample size in such studies is often faced with many challenges due to several methodological difficulties. While studies on power and sample size for cluster designs with one and two levels are abundant, the evaluation of required sample size for three-level designs has been generally overlooked. First, the nesting effect introduces more than one intracluster correlation into the model. Second, the variance structure of the estimated treatment difference is more complicated. Third, sample size results required for several levels are needed. In this work, we developed sample size and power formulas for the three-level data structures based on the generalized linear mixed model approach. We derived explicit and general power and sample size equations for detecting a hypothesized effect on continuous Gaussian outcomes and binary outcomes. To confirm the accuracy of the formulas, we conducted several simulation studies and compared the results. To establish a connection between the theoretical formulas and their applications, we developed a SAS user-interface macro that allowed the researchers to estimate sample size for a three-level design for different scenarios. These scenarios depend on which randomization level is assigned and whether or not there is an interaction effect.
495

The impact of sample size re-estimation on the type I error rate in the analysis of a continuous end-point

Zhao, Songnian January 1900 (has links)
Master of Science / Department of Statistics / Christopher Vahl / Sample size estimation is generally based on assumptions made during the planning stage of a clinical trial. Often, there is limited information available to estimate the initial sample size. This may result in a poor estimate. For instance, an insufficient sample size may not have the capability to produce statistically significant results, while an over-sized study will lead to a waste of resources or even ethical issues in that too many patients are exposed to potentially ineffective treatments. Therefore, an interim analysis in the middle of a trial may be worthwhile to assure that the significance level is at the nominal level and/or the power is adequate to detect a meaningful treatment difference. In this report, the impact of sample size re-estimation on the type I error rate for the continuous end-point in a clinical trial with two treatments is evaluated through a simulation study. Two sample size estimation methods are taken into consideration: blinded and partially unblinded. For the blinded method, all collected data for two groups are used to estimate the variance, while only data from the control group are used to re-estimate the sample size for the partially unblinded method. The simulation study is designed with different combinations of assumed variance, assumed difference in treatment means, and re-estimation methods. The end-point is assumed to follow normal distribution and the variance for both groups are assumed to be identical. In addition, equal sample size is required for each group. According to the simulation results, the type I error rates are preserved for all settings.
496

Vliv maternálních efektů na evoluci velikosti gekonů / Influence of maternal effect on body size evolution in geckos

Kubát, Jan January 2015 (has links)
In this diploma thesis has been tested potential of maternal influences on body growth at two model groups of geckos with large interspecific body size variability. The effect of egg manipulation to hatchling size was proved to be significant for hatchlings at both model species Paroedura picta and Goniurosaurus lichtenfelderi. However, in adult animals, there were no more significant body size differences caused by egg manipulation. It leads to conclusion that both species of geckos have compensatory growth and its adult size is likely to be primarily genetically determined. Key words: maternal effect, egg manipulation, body growth, allometric engeneering, Paroedura picta, Goniurosaurus lichtenfelderi
497

Variabilita v počtu obratlů a evoluce velikosti těla gekonů / Variability in vertebrae numbers and the evolution of body size in geckos

Vohralík, Martin January 2016 (has links)
In ectothermic vertebrates, body segmentation is often linked to final body length. This thesis focuses on the realtionship between final body length, ecological (temperature) and genetic (sex) factors and the count of body vertebrae in the Paroedura geckos, closely focusing on the Paroedura picta species. Individuals of this species were exposed to three different constant rearing temperatures, where they achieved different final sizes. We tested the correlation between the number of presacral vertebrae and final body size and the effect of rearing temperature and sex on the vertebrae number. The data point to high genetic and enviromental canalisation of the vertebrae count. Large conservation in the number of presacral vertebae were found even across the genus Paroedura regardless of the considerable evolutionary changes in body size. Powered by TCPDF (www.tcpdf.org)
498

Evoluce velikosti genomu v čeledi Costaceae / Genome size evolution in Costaceae

Böhmová, Alžběta January 2016 (has links)
Genome size in plants varies greatly; in angiosperms this variability can make a 2400- fold difference. This is why the subject of many studies is the attempt to explain these differences in various contexts. One of these is the phylogenetic viewpoint, which studies the relationships between genome size and different taxonomic groups. Many studies have been published so far which explore the plants of the temperate zone; there are however very few studies investigating genome size in tropical plants. For this reason, the subject of this thesis is the analysis of genome size in the pantropical family Costaceae Nakai. This family presently includes seven genera: Monocostus K.Schum., Dimerocostus Kuntze, Costus L., Paracostus C.D.Specht, Chamaecostus C.D.Specht & D.W.Stev, Hellenia Retz. and Tapeinochilos Miq., counting altogether about 300 species. The family is sister to the family Zingiberaceae, which has been notably better explored due to its economic importance. One of the aims of this thesis was a partial revision of the phylogeny published by Specht (2006). Molecular methods were used to analyse the phylogenetic relationships; these methods included classical sequencing of the trnL-F region and next-generation sequencing, where probes designed in advance were used to obtain the targeted genes....
499

One Size Fits No One: The Dramatic Truth About Size Discrimination in the Performing Arts

Read-Fisher, Kathryn 01 January 2017 (has links)
American theatre and media contribute to the violent systems of thinking around size and weight and its correlation to health. The argument that correlates higher body mass to lower overall health has been continuously disproved, and yet is still used as a tool to shame and justify sizeism. Educating the general public about health and size can assist in creating new models of representation and bodies can start to reclaim the space they deserve to take up, moving beyond the societal shame they currently face. In this thesis, sizeism is explored and unpacked through careful analysis of contemporary plays, television shows, and movies.
500

Reproductive decisions in the lesser black-backed gull Larus fuscus and their effects on reproductive success

Royle, Nicholas John January 1998 (has links)
The effect of several fundamental reproductive 'decisions' upon reproductive success were examined over a three year period at a large, inland gullery in the Pennines. Variations in reproductive parameters in relation to timing of breeding and reproductive success were compared among years. Determinants of the degree of hatching asynchrony were identified. Eggs from two years were taken for yolk lipid analysis, using gas chromatography. Variation in micronutrient content of eggs within clutches and between years was assessed in relation to egg size and yolk size, in order to examine resource allocation decisions of individuals. Timing of breeding of individuals was experimentally manipulated through the exchange of whole clutches of eggs between early and late laying birds, whilst controlling for variation in clutch size and egg-size, in order to assess whether the seasonal decrease in reproductive success was best explained by a decrease in food supply or differences in quality among parents. I experimentally manipulated the within-brood mass hierarchy of gulls, whilst controlling for variation in both chick quality and parental quality, in order to assess the effect of hatching asynchrony per se on chick growth and survival, and whether parents optimized the degree of hatching asynchrony with respect to the prevailing food supply. Brood size was experimentally reduced in order to assess the costs and benefits of the production of supernumary young. This was acheived by comparison of chick growth, feather development and chick survival of unmanipulated three-chick broods with broods where either the a-chick or the c- chick had been removed. I present a general discussion of the results within the context of life-history theory and a model for the evolution of hatching asynchrony in the lesser black-backed gull.

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