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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.
211

Faunal Composition and Distribution of Pelagic Larval and Juvenile Flatfishes (Teleostei: Pleuronectiformes) in the Northern Gulf of Mexico: Connectivity Between Coastal and Oceanic Epipelagic Ecosystems

Malarky, Lacey 08 December 2015 (has links)
Pleuronectiformes (flatfishes) occur throughout the global oceans, and have high ecological and commercial importance in some areas. Though much is known regarding life history, abundance, and distribution for the benthic adult stage of flatfish species, much less is known about the pelagic larval phases of flatfishes in the open ocean. Taxonomic uncertainty and limited sampling in the oceanic Gulf of Mexico contribute to data gaps with respect to the distribution of early life history stage of flatfishes in this region. Knowledge of the faunal composition, abundance and distribution of larval flatfishes, such as members of Bothus, which have extended pelagic phases, is important for modeling their population dynamics as well as for understanding the importance of connectivity between neritic and oceanic ecosystems in their life histories. Pleuronectiform specimens utilized in this study were collected in the northern offshore Gulf of Mexico during several cruises conducted throughout 2010-2011 as part of the NOAA Natural Resource Damage Assessment (NRDA) after the Deepwater Horizon Oil Spill (DWHOS). The Offshore Nekton Sampling and Analysis program (ONSAP) was established to determine composition, abundance and distribution of deep-water invertebrates and fishes in Gulf of Mexico waters that were potentially affected by the DWHOS. Results of the first large-scale discrete-depth distributional analysis of fishes in this region revealed that flatfishes were an intrinsic component of the oceanic ichthyofauna of these waters. A total of 2365 flatfish specimens were collected in offshore waters, representing four families and 11 of the 18 genera that occur in the Gulf of Mexico. Species composition was dominated by members of the genus Bothus, which had a high frequency of occurrence in the epipelagic zone throughout the year. Citharichthys spilopterus and Trichopsetta ventralis were the second- and third-most abundant and frequently occurring taxa, respectively. Detailed spatial analyses of taxa in the epipelagic zone revealed that larvae of Citharichthys spilopterus were only collected in winter and occurred most frequently near the continental shelf break, while early life stages of Bothus spp. were more abundant at the northern convergence flow of a large anticyclonic Loop Current eddy during spring and summer.
212

Příprava k trestnému činu / Crime preparation

Verner, David January 2017 (has links)
The master's thesis comprehensively deals with the issue of the preparation of a criminal offence and other disputable questions related with this stage in the commission of a criminal offence. The emphasis is mainly put on its definition in the Czech criminal law, taking account of relevant judicial decisions necessary to interpret the relatively brief statutory provisions. The aim of the thesis is to carry out critical evaluation of the current legislation sanctioning preparation, to identify questionable parts and potential shortcomings that may exist in the practice. On this basis I try to suggest solutions to the identified problems or at least to contribute to the discussion about them. The thesis is divided into five parts, the first generally puts the preparation into the criminal law system, describes its various forms, distinguishes it from the other stages in the commission of the criminal offence and briefly describes the historical development of its sanctioning on our territory. The second part focuses on the problematics of the impossible preparation and issues regarding its criminalization and punishing. The third part deals with a specific reason for extinction of criminal liability for the preparation, namely the voluntary refraining from further preparatory acts. The attention is...
213

Larvální morfologie tribu Goliathini (Coleoptera: Cetoniinae) a její využití při studiu fylogeneze zlatohlávků. / Larval morphology of Goliathini (Coleoptera: Cetoniinae) and its contribution towards the understanding of the group's evolution.

Kouklík, Ondřej January 2017 (has links)
1 Abstract Currently there are almost 4000 described species of rose chafers (Scarabaeidae: Cetoniinae) but larvae of less than 200 species are described. In this work we studied larval morphology of 86 species belonging to 58 genera with focus on the tribe Goliathini. The larvae of 21 genera were studied for the first time. 77 morphological characters on head, mouth parts, legs and thoracal and abdominal segments were studied. This resulted into large matrix of morphological characters, which were further tested in separate phylogenetical analyses. A checklist of studied characters and their states and also large databasis of photographs of the characters are also amongst the results of the thesis. Five independent datasets were tested, three were based singly on morphology, one on molecular sequences and one on a combined dataset. The phylogenetic analysis was made by three methods, maximum parsimony, maximum likelihood and bayesian interference. Eleven different phylogenetic trees were obtained as a result, based on which we tried to reconstruct the relationships between the inner groups of Cetoniinae with focus on relationship of subtribes of tribe Goliathini. Monophyly of the tribe Goliathini as well as some other groups could not be confirmed, as well as the alleged basal position of the genus...
214

The impact of the Intellectual Property Rights Act for publicly funded research and development on technology transfer offices at South African universities

Erasmus, Norman 26 May 2012 (has links)
The impact of the Intellectual Property Rights Act for publicly funded research and development on technology transfer offices was studied, using a questionnaire survey and guided interviews of six technology transfer officers. The survey requested technology transfer officers to express the impact level of each of the eleven impact elements on the four stages of intellectual property development – these being intellectual property creation, disclosure, protection and commercialisation. The set of data was weighted for each element, by intellectual property development stage, and analysed using frequency tables. The impact elements of „structural and resource requirements to commercialise and manage intellectual property‟, „intellectual property detection process by the technology transfer officers‟, and‟ disclosure process‟ were ranked as the top three impact elements, in that respective order. Narrative inquiry and theme extraction allowed further elaboration of the impact elements. Comparison with Staphorst‟s (2010) results showed that the impact elements were different for science councils, pointing to unique requirements by universities in their intellectual property management systems. The results of this analysis clearly indicate that the Intellectual Property Rights Act enforcement and execution will demand a high degree of structural and resource requirements, particularly, and most importantly, at the intellectual property disclosure stage of intellectual property development. Copyright / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted
215

Tolerance of selected crops to gypsiferous water originating in coal mines

Mentz, Wilma Henriette 11 November 2003 (has links)
The disposal of gypsiferous water, generated in coal mining operations, has become a problem in the Mpumalanga Highveld region in South Africa. As part of an investigation into the feasibility of using this water for irrigation, sand and water culture experiments were conducted in a glasshouse and growth chambers to determine growth responses of maize, sorghum, pearl millet, sunflower, soybean, cowpea, dry bean, wheat, rye, triticale, oats, barley, annual ryegrass, and lucerne cultivars to gypsiferous mine water in the germination, seedling and vegetative growth stages. Germination %’s were generally not affected. The seedling growth of maize, sorghum, pearl millet and lucerne was more sensitive and showed more significant cultivar differences than the seedling growth of soybean and the annual temperate crops. Seedling growth curves with increasing concentrations of Ca, Mg and SO4 followed a similar pattern for most of the crops: where CaSO4 was in solution, growth decreased in a linear manner, but above saturation concentrations with increasing gypsum crystal content, it increased despite decreasing osmotic potentials of the treatment solutions. The vegetative growth of sunflower, lucerne, dry bean and rye was more tolerant than seedling growth, but was more sensitive for maize and cowpea, and the same as seedling growth for sorghum, pearl millet, wheat, oats, triticale and annual ryegrass. It was concluded that the major property of this water that suppressed growth was the decreased osmotic potential. However, it is the ‘effective’ osmotic potential (i.e., the average osmotic potential during the whole growth period) and not that of the treatment solutions, that was mainly responsible for the eventual growth. The ‘effective osmotic potential’ is determined by evapotranspiration and the rapidity of gypsum precipitation, which in turn may be affected by the growth rate, temporal, environmental and soil factors. Sensitivity of crops and growth stages is therefore related to its sensitivity to the external osmotic potential, whereas tolerance both in the seedling and vegetative growth stages was found in crops primarily affected by the ionic effects of Na and/or Cl. Possible nutrient effects due to the high Ca and SO4 need further investigation. / Thesis (PhD (Plant Production and Soil Science))--University of Pretoria, 2004. / Plant Production and Soil Science / unrestricted
216

The experiences of adolescents dealing with parental loss through death

Wieruszowski, Leanne Clare 09 January 2009 (has links)
This research focuses on the experiences of adolescents dealing with parental loss through death, irrespective of the age of the child at the time of loss. Through an increased understanding of this phenomenon, the researcher highlights the need for supporting and guiding adolescents who are dealing with parental loss. Role players are identified and insight into the task of assisting adolescents who are dealing with parental loss through death, is developed. A qualitative approach was followed in order to gain in-depth data regarding the experiences of adolescents dealing with parental loss through death. The general orientation to the research methodology is discussed in chapter one. The first objective of the study was to build a theoretical frame of reference regarding the field of adolescence as well as the influence of parental loss and the grief process, on this developmental stage. This objective is achieved in chapters two and three The second objective was to conduct an empirical study on the experiences of adolescents who were dealing with parental loss through death. The researcher conducted interviews at the school in which she works. Play techniques were implemented by the researcher to assist in exploring the adolescents’ experiences and therefore facilitate the research process. Themes and sub-themes were identified during the data collecting and analyzing processes. The findings are discussed in chapter four. The main themes, relating to the experiences of adolescents dealing with parental loss, identified in this study, are: <ul> <li> Emotions and needs vary and are linked to both the process of grieving and the development of a separate identity. <li> Although many possible support systems exist, insufficient guidance and support, both formal and informal, are being offered. <li> The adolescents’ focus on the past, present and future is affected by parental loss. <li> The relationship with the parents, both deceased and surviving, affects the adolescents’ functioning in the present. <li> Secondary implications of parental loss affect the adolescents’ experience of the loss. <li> Identity formation is affected by the bereavement process. <li> Risk and protection factors include present relationships and support systems; being offered the opportunity to grieve; spiritual beliefs and the adolescents’ behaviour. <li> Physical effects of dealing with parental loss though death included symptoms of depression.</li> </ul> The final objective of the research was to provide conclusions and recommendations and receives attention in chapter five. Recommendations are made to the South African Government, Department of Education and schools and include proposed strategies and policies for offering support to adolescents dealing with parental loss within the school systems. Recommendations to social workers and other professional support structures include bereavement training, flexible service delivery options and the developing and empowering of community-based structures. Knowledge of the experiences of adolescents dealing with parental loss through death is increased and the need for offering support and guidance to this vulnerable group in our society receives attention through this research. / Dissertation (MSD)--University of Pretoria, 2009. / Social Work and Criminology / unrestricted
217

Family Communication Concerning End-of-Life Care Preferences

Peterson, Lindsay Jo 15 November 2016 (has links)
Communication concerning the care one wishes to receive at the end of life (EOL) is central to ensuring that wishes are honored. Many studies have examined doctor-patient or doctor-family EOL communication. However, relatively few studies have focused on the occurrence of EOL care discussions among family members. This is an important topic, as research suggests that advance directives (ADs) are ineffective if patients have not involved surrogate decision-makers, most of whom are family members. This study examined EOL care discussions among family members. It used quantitative and qualitative data from a diverse sample of older adults from West Central Florida collected for the purpose of this examination. The quantitative and qualitative data were analyzed separately and together. This study employed the Transtheoretical Model, which proposes that individuals are in varying behavioral “stages of change” and that bringing about a behavioral change requires understanding their particular stage and adapting interventions appropriately. Statistical analysis of the quantitative data (N=364) using multinomial logistic regression showed that participants were in distinct stages that were associated with several factors, including family involvement with health care decision-making and communications with doctors. Racial and ethnic differences were not found in controlled analysis, though Hispanics were less likely to be in more advanced EOL care discussion stages in unadjusted analyses. Several themes were found in qualitative analysis of focus groups (n=36) drawn from the larger sample. Findings suggested that those who engaged in family EOL care discussions were more careful planners overall, more accepting of death, and able to manage complex family dynamics. They also had greater knowledge of EOL matters, largely related to knowledge of loved ones EOL wishes. The quantitative-qualitative (mixed-methods) study reinforced the role of family relationships in general in whether EOL care discussions occurred. It also highlighted the role of being proactive and having EOL care knowledge. All three studies – the quantitative, qualitative, and mixed methods showed the potential for doctors and other health professionals to help families with EOL care discussions and ACP overall.
218

Passion and Fear effects on student entrepreneurs

Kuri, Avijit, RenFei, Wang January 2017 (has links)
Entrepreneurship has been gotten fruitful attentions all around the world, it also has become one of the most significant engines for both national economic and social growth. The internal factors, which are able to affect entrepreneur’s behaviors during the whole entrepreneurship life cycle, are gradually becoming a hot topic in both practical and academic research fields. Especially for some of the famous researchers, such as Melissa Cardon and Mitchell, J.R. are leading the academic research of the relation between entrepreneurial emotions (e.g., passion and fear) and behaviors. In this study, our objective is to understand how passion and fear effect student entrepreneur’s behaviors when they are running their businesses at the early stage of entrepreneurship. Moreover, semi structured interview has been chosen to collect qualitative materials for this Master thesis paper. In this case, eight student entrepreneurs from Linnaeus University in Vaxjo, Sweden who are studying and running their business at the same time, or have finished their study already but started their business while they were students are selected by us for doing the interview. Furthermore, we broadly discussed about different stages of entrepreneurship, also entrepreneurial passion and fear along with entrepreneurial internal emotions such as cognition, self-regulation, self-efficacy, persistence, which could influence student entrepreneurs’ behaviors to start up their business and afterwards. Finally, after empirical analyzing we found that the bright side of passion and fear have positive effects on student entrepreneurs’ behaviors, whilst the negative effects of passion and fear can hinder their behaviors during the early entrepreneurial process.
219

Improved condition monitoring of composite insulators

Da Silva domingues, Elizabeth January 2012 (has links)
Although the cost of investment in power lines insulators is 3-5% of the total cost of the installation, the impact of their performance on reliability, failure costs, maintenance routines, etc in power systems is tens of times higher. Composite insulators were introduced 50 years ago and have been used around the world with consistently good experience. Low weight, easy handling, good performance under high pollution, low maintenance costs, and resistance to vandalism are some of their advantages. Nevertheless, acid rain, salty dust deposition, corona discharges, ozone, UV radiation, and humidity among other factors, deteriorate the quality of the polymeric housing reducing their hydrophobicity. The synergistic action of ageing factors is extremely complex and the whole degradation process may change when any one variable is slightly modified. Many studies have been carried out to increase understanding of the physicochemical processes which control the electrical and mechanical stability of polymers during in-service ageing with the objective of predicting remaining life-times. Vital areas of knowledge about polymer insulators are still incomplete and lacking; three of them are: (1) early stages of degradation in service under different environmental conditions, (2) monitoring and diagnosis techniques suitable for distribution installations and (3) steps to establish an insulators management plan based on condition and risk of failure. In this research these three topics are covered. A full review of literature about management of electrical distribution assets is included, followed by a specific plan developed for monitoring, diagnosis and ranking of insulators mainly supported by visual inspections. Diagnosis of medium voltages EPDM insulators recovered from service aged under different conditions is done using both traditional techniques and, uniquely, dielectric impedance. The relationship between surface roughness and static contact angle is also used to characterize insulators' surfaces. Early stages of degradation are studied focusing the experimental work to evaluate the electrohydrodynamic processes which occur on new samples under different conditions, giving special attention to leakage current pulse analysis, electric field enhancement, and resistance/capacitive behaviour including phase of leakage current. Results from each specific topic offer additional understanding of polymer insulators degradation providing insight to monitoring, diagnosis and management. Additionally, results open new topics in which new investigations are proposed.
220

Water stress effects on growth, yield and quality of wheat (Triticum aestivum L.)

Mbave, Zwidofhelangani Aubrey 25 April 2013 (has links)
Understanding the effects of water stress on wheat growth, yield and quality is essential for good irrigation management. In South Africa most of the wheat production areas are vulnerable to drought stress during crop development. That causes substantial reduction in grain yield, depending on the developmental stage at which water stress occurred. Supplemental irrigation is the main strategy for adaptation and stabilisation of yield under water stress. However, agriculture is the leading single water-use sector locally, consuming about 60% of total available water. Therefore, the need to improve water use efficiency (WUE) in crop production is clear, since South Africa is classified as a water-scarce country. Experiments were conducted under a rain shelter at Hatfield Experimental Farm, University of Pretoria, in the 2010 and 2011 seasons. The main objective of the study was to evaluate the effects of water stress at different stages on growth, yield, and quality of three wheat cultivars, namely Duzi, Steenbras and SST 843. Water stress was imposed by withholding water at either of three growing stages. The first treatment was stressed during tillering stages to flag leaf (stem elongation (SNN)), followed by water stress from flag leaf to the end of flowering (flowering stage (NSN)), and lastly water stress from grain filling to physiological maturing (grain-filling stage (NNS)), whereas optimal supply of water was maintained throughout the season by weekly irrigating to field capacity for the control treatment (NNN). Irrigation treatments and cultivars influenced growth, yield and quality, depending on the developmental stage at which irrigation was withheld. The control treatment (NNN) and the treatment stressed in the flowering stage (NSN) had highest and lowest grain yield respectively in both seasons. Water stressed treatment NSN reduced grain yield by 33% and 35% in the 2010 and 2011 seasons respectively, when compared with the control treatment (NNN). Reduction of grain yield due to stress in the flowering stage (NSN) was ascribed to reduction in the number of seeds per ear, number of ears per unit area, ear length, and flag-leaf photosynthesis rate (Pn). In the flowering stage (NSN) water stress reduced Pn by 59% which was due to increased leaf temperature because of lower transpiration (E) and stomatal conductance (gs). The water stress treatment NSN reduced transpiration by 72% and stomatal conductance by 84% in the flowering stage. Plant height was reduced by 23% because of water stress imposed in the flowering stage (NSN), which consequently decreased biomass yield by 29% in the 2011 season. Growth and yield parameters showed dramatic recovery when stress was terminated during the flag-leaf stage (SNN). The cultivar Steenbras had lower yield reduction under stress, whereas Duzi and SST 843 had higher yield potential under the well-watered conditions (NNN). In the 2011 season SST 843 had higher WUE of 14.2 kg ha-1 mm, which corresponded to higher grain yield of 7210 kg ha-1 and higher ET of 509 mm. Water-stress treatment SNN gave the highest WUE of 14.9 kg ha-1 mm, which corresponded to a total water use (ET) of 451 mm and grain yield of 6738 kg ha-1. Water stress treatments SNN and NNS reduced ET by 27% and 17%, respectively, which translated to 173 mm and 105 mm water saved by each treatment correspondingly. Grain protein content (GPC) was reduced most by the treatment exposed to stress in the stem elongation stage (SNN). However, the GPC was acceptable (>12%) in all treatments in both seasons. Hectolitre mass was reduced most by water stress imposed during grain filling (NNS). Water stress treatment NNS lowered the hectolitre mass by 3% and 4% in the 2010 and 2011 seasons respectively. Generally all quality parameters in the present study were acceptable for all irrigation treatment and cultivars. The hypothesis that water stress in the stem elongation and grain-filling stages will have little effect on yield and improve WUE was accepted. Therefore it can be recommended that supplemental irrigation should be applied from flag leaf to end of flowering (NSN) stages of wheat in order to minimise grain yield losses in the absence of rainfall. Further research should focus on extrapolation of these results to other production regions using crop models. / Dissertation (MInstAgrar)--University of Pretoria, 2013. / Plant Production and Soil Science / unrestricted

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