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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.
271

Att växa upp i våldets närhet : ungdomars berättelser om våld i hemmet / Growing up in the proximity of violence : teenagers' stories of violence in the home

Weinehall, Katarina January 1997 (has links)
In this dissertation, teenagers (13-19 years) are allowed to speak out. The purpose of the study was to gain knowledge regarding the conditions related to socialization in the proximity of violence through listening to, interpreting and attempting to understand the teenagers' narratives about life when violence is an everyday occurrence. Primarily, I wanted to obtain a picture of the conditions under which these girls and boys grew up as they themselves described them. My questions are primarily concerned with the teenagers' experiences of violence in the home, the strategies they used to cope with a violent home environment and finally with their self-images. Secondarily, my intention was to analyze and interpret the picture that emerged in an attempt to understand the meaning of socialization in the proximity of violence, primarily based upon theories of sexualized violence (aspects of gender and power), coping, resilience, and the social heritage of violence-related behavior (the inter-generational transmission of violent behavior). My purpose was also to relate the descriptions and analysis of domestic violence, and the associated conditions under which these young people grew up, to previous research within the field of family violence. The dissertation is grounded in feminist theory which views the gender and power relationships between women and men as a determining principle of social organization. I associate this with the established Scandinavian concept of "sexualized violence," used to describe forms of abuse and sexual exploitation such as rape, incest and other sexual assaults, pornography, the sex trade and sexual harassment. Fifteen teenagers living in Sweden volunteered to be informants for the study. They were interviewed six to ten times each over a four year period. The interviews progressed in steps from background information to the most private and sensitive questions about the violence which had taken place in the home. The number of interviews was determined case by case; the interviews were concluded when no or few new aspects emerged. The analysis is based in part upon the categorized statements and in part upon the longer narratives. The results show that the young people exist in the presence of violence as witnesses to and victims of violence perpetrated by their fathers. The children are threatened into silence and bear inner feelings of powerlessness and loneliness. They are regarded as different in school, bullied by peers and disregarded by adults. In this double victimization, the children feel themselves to be unwanted and worthless. If the child breaks the secrecy and seeks help, he or she experiences utter betrayal, foremost from social authorities. The lack of protective factors and insightful adults is nearly total. The very essential contact with peers has also been denied them. The children feel themselves to be completely abandoned. Using their own resources, they yet manage to formulate their thoughts, create meaning in events and become survivors. / digitalisering@umu
272

The effect of charcoal on tissue morphogenesis in vitro.

Pan, Manjing. 17 December 2013 (has links)
The effect of activated charcoal, autoclaving and culture media on sucrose hydrolysis in tissue culture media was investigated. Activated charcoal acidified an aqueous sucrose (5%) solution and culture media by about 1 to 2 units after autoclaving . Sucrose hydrolysis in tissue culture media and/or aqueous sucrose (5%) solutions containing activated charcoal (buffered to pH 5.8) was dependent on both the hydrogen ion concentration (pH) and autoclaving. After autoclaving, 70%, 56% and 53% sucrose hydrolysis were respectively recorded in a 5.0% sucrose solution, Murashige and Skoog (MS) and Gamborg B5 (B5) liquid media in the presence of 1.0% activated charcoal, added before autoclaving . In the absence of activated charcoal, autoclaving resulted in about 20% of the sucrose being hydrolysed The adsorption of 2, 4-dichlorophenoxyacetic acid (2,4-D) by activated charcoal from methanol and aqueous solutions was determinated using HPLC. The amount of the added 2,4-D decreased in both methanol and aqueous solutions in the presence of activated charcoal, compared with those in the absence of activated charcoal. In methanol and aqueous solutions, activated charcoal used at the level of 0.1% significantly reduced 2,4-D. About 68.4% and 60.9% respectively of the added 2,4-D was adsorbed by activated charcoal (1.0%) from these solutions. The changes of inorganic elements in MS-salt solutions, in the presence of activated charcoal, were analysed by SEM-EDX. The concentrations of magnesium (Mg), calcium (Ca), iron (Fe) and zinc (Zn) deceased in the presence of activated charcoal, while the concentrations of potassium (K), copper (Cu), manganese (Mn), phosphorus (P), and sulphur (S) increased in the MS salt solution in the presence of activated charcoal compared with no activated charcoal in the medium. This suggests that activated charcoal adsorbed calcium, magnesium, iron and zinc and released copper, manganese, phosphorus and sulphur. Rooting occurred when 7-day-old seedling hypocotyls of Daucus carota L. Cape Market were placed on MS medium supplemented with 2,4-D, and IAN/NAA in the presence of activated charcoal. Hypocotyls did not produce roots on the 2,4-D containing media in the absence of activated charcoal. The roots were produced polarly on the NAA/IAA-containing media in the presence of activated charcoal. No-polarity of root formation was observed on media supplemented with NAA/IAA without activated charcoal. Different responses of hypocotyls to a series of 2,4-D concentrations (0.5, 1.0, 3.05.0, 8.0, and 10.0 mg l ¯¹) were observed on media supplemented with 0.02, 0.1 and 0.5% activated charcoal. In the NAA/IAA containing media in the presence of activated charcoal, root number per hypocotyl decreased. Root number perhypocotyl, on the media supplemented with NAA and IAA, increased when hypocotyls were pre-cultured on MS medium supplemented with 2,4-D (1.0 mg l ¯¹) for 2-3 days. When hypocotyls were pre-cultured on a 2,4-D containing MS medium for 5 days, embryos emerged from the hypocotyls directly on the medium supplemented with 2,4-D in the presence of activated charcoal. Addition of activated charcoal to MS medium supplemented with 2,4-D resulted in somatic embryogenesis of Daucus carota. Somatic embryos were not formed on the medium in the absence of activated charcoal. In suspension culture, the incorporation of 0.01 to 1.0% concentrations of activated charcoal to the MS medium, irrespective of 2,4-D, increased the number of somatic embryos produced. The maximum number of somatic embryos were produced with 1.0% activated charcoal. Further development of embryos of Daucus carota occurred on the media in the presence of activated charcoal, and the embryos subsequently regenerated normal plantlets. Abnormal somatic embryos followed the addition of 3.0% activated charcoal to the medium. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 2000.
273

Recirculating hydroponic systems : evaluating cuttings yield and rooting ability of cold tolerant eucalyptus hybrids.

Wallis, Jacqueline Tanya. January 2004 (has links)
In South Africa, clonal forestry of Eucalyptus and its hybrids has been implemented to increase the productivity on existing forestry lands and marginal sites and to facilitate the production of desired fibre types for timber processing operations. The cold-tolerant Eucalyptus grandis x E. nitens hybrids have produced consistently high yields, and are propagated clonally with limited success via a macro-cutting system currently in use for other hybrid species. The heart of vegetative propagation operations is the clonal hedge and its management, and nutrition in particular, is an important element of any vegetative propagation programme. However, achieving and sustaining an optimum nutritional balance in macrohedges is difficult in practice and, in order to accurately predetermine the optimum plant nutrition required all year round and to ensure optimal levels of rooting, a more controllable nutrient environment is essential. Hydroponics may facilitate this control of nutrition. At the same time it may be possible to manipulate the system to determine accurately what levels of each nutrient may contribute to the highest rooting and more importantly allow forest nursery managers to maintain those levels in a practical manner. The main aims of the present work were to obtain and compare cuttings and rooting yields from hydro-ramets in different hydroponic substrates and systems and to investigate the possible roles of essential nutrients on those parameters. Modified Nutrient Film Technique (NFT), ebb-and-flow and aeroponic tables were used in this study. The former consisted of eight individual gutters, allowing for eight different substrates to be tested simultaneously. One gutter was set up as an unmodified NFT table and the other seven gutters had gravel, Leca, peat, perlite, perlite: vermiculite mix, Rockwool® and sand as substrates; all were supplied with the same nutrient solution. Three commercial clones were used throughout these trials: GN107, GN156 and NHOO. Rooting results and data from plant elemental analyses indicated that certain elements (Ca, Cu, Zn, Mn and B) appeared to play a more important role in rooting than others (N, P, K, Mg, Na and Fe). It was also found that when comparing the hydroponic systems, the substrate and / or method of irrigation affected the availability and uptake of different nutrients, which in turn affected the rooting of coppice collected from those ramets. The rooting performance of coppice from the eight different substrates tested in the NFT system was compared. Within each of the four harvests undertaken, both clone and substrate had a significant effect on the rooting performance. However, when the four harvests were compared, only harvest number/time had a significant effect on the rooting performance of the cuttings derived from the hydro-hedges . For both the ebb-and-flow and aeroponics systems (where there was no substrate), only the clone had a significant effect on the rooting performance. In addition to this, the plants from the ebb-and-flow system produced the highest number of cuttings to be placed overall (7.9 cuttings per mother plant per harvest) while those from the gravel substrate had the highest rooting percentage overall (26.9 %). When combining these two factors into a success rate, the perlite substrate rated highest (1.7 rooted cuttings per mother plant per harvest). From a cost efficiency perspective, perlite was the most cost effective substrate, as it required the least initial capital outlay to produce one million rooted clones per year from a hydroponics system (R6 533 655). The plants in the perlite substrate also produced the highest number (6 700) of rooted cuttings per year from 1 000 mother plants with a low cost per plant (R2.33 per rooted plant). / Thesis (M.Sc.)-University of KwaZulu- Natal, Durban, 2004.
274

Corporate social responsibility: environmental concern in New Zealand's wine industry

Gabzdylova, Barbora January 2008 (has links)
Corporate social responsibility (CSR) has become a worldwide issue as organizations are under increasing pressure to behave in socially responsible ways. Environmental responsibility as a part of CSR is often connected with sustainability and protection the environment. This is of a significant importance to New Zealand and its 'clean' and 'green' image. One industry having an impact on the environment, and also having a strategic position in the economy of New Zealand is the wine industry. The aim of the research is to understand what motivates and sustains companies' CSR practices. This exploratory study examines (1) what drives the industry to engage in CSR practices, (2) the role of stakeholders in the company's decision making, and (3) CSR practices in the wine industry. A qualitative research approach supplemented by quantitative measures was adopted to answer the research questions. 24 case study organizations (wineries) were studied and 31 managers interviewed. The research found that the most important drivers of CSR practices are personal values, preferences and satisfaction with this profession. This is followed by product quality and customers' demand. Though New Zealand wine companies are also driven by the market; the market still does not value CSR initiatives and companies do not receive a price premium for sustainable or organically grown grapes. Furthermore, environmental regulations belong to important drivers affecting companies' decision-making. However, companies do not consider current New Zealand's regulations as significantly difficult to follow. On the other hand, companies want to preempt future regulations. The research also revealed that the most important stakeholders are owners, shareholders, customers, wholesalers and international businesses. The role of communication and ecolabelling is also discussed. As a result, the study proposes a typology matrix that differentiates organizations' involvement in CSR according to the extent of CSR practices and their drivers. This study contributes to understanding of the New Zealand wine industry status in environmental CSR at the present, the extent of drivers of proactive environmentalism and companies' stakeholders, and the description of a typology matrix of companies engaging in CSR. This contribution is valuable for those interested in CSR, and the future of New Zealand's wine industry.
275

STANDARDIZED ILEAL DIGESTIBLE TRYPTOPHAN TO LYSINE RATIOS IN GROWING PIGS FED U.S. TYPE AND NON U.S. TYPE FEEDSTUFFS

Quant, Anthony David 01 January 2008 (has links)
The objective of these studies was to determine the optimum standardized ileal digestible tryptophan to lysine (SID Trp:Lys) ratio for growing pigs fed both U.S.–type (corn–soybean meal) and non–U.S.–type (wheat–barley) diets. When feeding U.S.–type diets, average daily gain (ADG) and plasma urea nitrogen (PUN) concentrations improved as SID Trp:Lys ratios increased, yielding optimum ratios of 15.32% (P<0.001) and 15.25% (P<0.001), respectively. Averaging these resulted in an optimum SID Trp:Lys ratio of 15.29%. In non–U.S.–type diets, feeding increasing SID Trp:Lys ratios improved ADG and PUN, displaying optima of 15.99% (P=0.048) and 15.29% (P=0.054), respectively. This produced an average optimum SID Trp:Lys ratio of 15.64%. The final study included the other dietary essential amino acids (EAA) at a higher level, and ADG and PUN improved as SID Trp:Lys ratios increased, yielding optima of 17.93% (P<0.001) and 16.17% (P=0.009). This averaged to an optimum SID Trp:Lys ratio of 17.05%. Overall, diet composition did not affect the Trp:Lys requirement of growing pigs, however, feeding the other EAA at higher levels resulted in a higher estimated optimum SID Trp:Lys ratio. The optimum SID Trp:Lys ratio is estimated to lie between 15.29% and 17.05%.
276

PHOSPHORUS DIGESTIBILITY AND PHYTATE DEGRADATION IN LONG YEARLINGS AND MATURE HORSES

Fowler, Ashley 01 January 2013 (has links)
Much of the phosphorus (P) in grain-based concentrates fed to growing horses is in the form of phytate-P. Little is known about the ability of young horses to degrade phytate-P or whether age affects mineral digestion in horses. The objective of this study was to examine the effect of age on P, calcium (Ca), and magnesium (Mg) digestibility and phytate-P degradation. Four long yearling geldings and 4 mature geldings were fed a diet of alfalfa cubes, timothy cubes and a pelleted concentrate. The diet contained 0.28% total P and 17.4% of that P was in the phytate form. There was a 14-d diet adaptation period followed by a 4-d fecal collection period. There was no difference in apparent P digestibility between the 2 age groups (P > 0.05). Phytate-P disappearance was 94.8% and did not differ between ages (P > 0.05). Apparent Ca digestibility tended to be higher in mature geldings (P = 0.0526), but apparent Mg digestibility did not differ between ages (P > 0.05). Long yearlings have the same ability to digest P and Mg as mature geldings, but more research is needed to determine the effect of age on Ca digestibilities.
277

Solving Nested Recursions with Trees

Isgur, Abraham 19 June 2014 (has links)
This thesis concerns the use of labelled infinite trees to solve families of nested recursions of the form $R(n)=\sum_{i=1}^kR(n-a_i-\sum_{j=1}^{p_i}R(n-b_{ij}))+w$, where $a_i$ is a nonnegative integer, $w$ is any integer, and $b_{ij},k,$ and $p_i$ are natural numbers. We show that the solutions to many families of such nested recursions have an intriguing combinatorial interpretation, namely, they count nodes on the bottom level of labelled infinite trees that correspond to the recursion. Furthermore, we show how the parameters defining these recursion families relate in a natural way to specific structural properties of the corresponding tree families. We introduce a general tree ``pruning" methodology that we use to establish all the required tree-sequence correspondences.
278

Solving Nested Recursions with Trees

Isgur, Abraham 19 June 2014 (has links)
This thesis concerns the use of labelled infinite trees to solve families of nested recursions of the form $R(n)=\sum_{i=1}^kR(n-a_i-\sum_{j=1}^{p_i}R(n-b_{ij}))+w$, where $a_i$ is a nonnegative integer, $w$ is any integer, and $b_{ij},k,$ and $p_i$ are natural numbers. We show that the solutions to many families of such nested recursions have an intriguing combinatorial interpretation, namely, they count nodes on the bottom level of labelled infinite trees that correspond to the recursion. Furthermore, we show how the parameters defining these recursion families relate in a natural way to specific structural properties of the corresponding tree families. We introduce a general tree ``pruning" methodology that we use to establish all the required tree-sequence correspondences.
279

Contributions to 3D Image Analysis using Discrete Methods and Fuzzy Techniques : With Focus on Images from Cryo-Electron Tomography

Gedda, Magnus January 2010 (has links)
With the emergence of new imaging techniques, researchers are always eager to push the boundaries by examining objects either smaller or further away than what was previously possible. The development of image analysis techniques has greatly helped to introduce objectivity and coherence in measurements and decision making. It has become an essential tool for facilitating both large-scale quantitative studies and qualitative research. In this Thesis, methods were developed for analysis of low-resolution (in respect to the size of the imaged objects) three-dimensional (3D) images with low signal-to-noise ratios (SNR) applied to images from cryo-electron tomography (cryo-ET) and fluorescence microscopy (FM). The main focus is on methods of low complexity, that take into account both grey-level and shape information, to facilitate large-scale studies. Methods were developed to localise and represent complex macromolecules in images from cryo-ET. The methods were applied to Immunoglobulin G (IgG) antibodies and MET proteins. The low resolution and low SNR required that grey-level information was utilised to create fuzzy representations of the macromolecules. To extract structural properties, a method was developed to use grey-level-based distance measures to facilitate decomposition of the fuzzy representations into sub-domains. The structural properties of the MET protein were analysed by developing a analytical curve representation of its stalk. To facilitate large-scale analysis of structural properties of nerve cells, a method for tracing neurites in FM images using local path-finding was developed. Both theoretical and implementational details of computationally heavy approaches were examined to keep the time complexity low in the developed methods. Grey-weighted distance definitions and various aspects of their implementations were examined in detail to form guidelines on which definition to use in which setting and which implementation is the fastest. Heuristics were developed to speed up computations when calculating grey-weighted distances between two points. The methods were evaluated on both real and synthetic data and the results show that the methods provide a step towards facilitating large-scale studies of images from both cryo-ET and FM.
280

Being young in the country: settler children and childhood in British Columbia and Alberta, 1860-1925.

Bridge, Kathryn Anne 03 August 2012 (has links)
This dissertation demonstrates that the voices of children and the experiences of childhood provide important new perspectives about the settler societies in British Columbia and Alberta during the period 1860 – 1925. It employs a combination of direct quotations from individual children and analysis across the cohort of one hundred historical children as a means to explore both individual personalities and shared child perspectives of childhood. Child-created diaries and correspondence were selected as the principal documentation in this study as a deliberate strategy to privilege children and to enable clear child-centred voices unmixed with those of adults. The intent is to reveal child-centred understandings about the physical and emotional aspects of growing up in Western Canada that are set within the contexts of specific communities, of family life, of sibling relationships, of friendships and separations. Some significant findings include the phenomenon of boarding school within the childhood experience and the realization that many settler children spent childhoods away from family, the difficulty boys shared in achieving masculinity, and the importance placed by girls and boys on charting and comparing their physical growth and attainment of child-centred milestones of achievement. / Graduate

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