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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.
1011

The role of informational support in relation to health care service use among individuals newly diagnosed with cancer /

Dubois, Sylvie. January 2008 (has links)
No description available.
1012

Analysis of energy efficiency of cooperative MIMO schemes

Krishnan, Narayanan January 1900 (has links)
Master of Science / Department of Electrical and Computer Engineering / Balasubramaniam Natarajan / Recently, user-cooperative MIMO (multi-input multi-output) systems have been generating significant interest due to their capacity/performance gains over SISO (single-input single-output) systems. In cooperative MIMO architectures, individual nodes with single antennas collaborate with each other to act as a MIMO unit. As a result, the individual node complexity associated with traditional MIMO implementations is alleviated. This feature is especially beneficial in sensor networks and cellular systems where individual node energy, size and cost are important constraints. Additionally, cooperative MIMO schemes provide all the benefits of traditional MIMO systems. In this work, we classify the cooperative MIMO systems into three different categories equivalent to classical MIMO, MISO and SIMO systems. For the three protocols, we quantify and compare the energy efficiency of Amplify-and-Forward (AF) and Decode-and-Forward (DF) schemes on a basic three node cooperative network. Total energy is calculated considering circuit energy as well as transmission energy. For AF and DF schemes, we set a target Symbol Error Probability (SEP) and evaluate the minimum transmission energy for achieving the target SEP. In this process,we first derive an approximation for SEP at high SNR. Then, we formulate the transmission energy calculation as an optimization problem subject to the target SEP and present the theoretical solution. The result is used to compare the total energy consumption of AF and DF for the three protocols. This is unlike most of the prior efforts that primarily focus on optimum allocation of limited total power to maximize the some peformance criterion. Since any wireless systems in order to operate have a set performance criterion, we intend to minimize the resources that is capable of achieving that.
1013

Expérience de soins de patients aînés atteints de cancer à l’urgence / Health care experience of older cancer patients in the context of emergency room visits

Nguyen, Bich Lien January 2016 (has links)
Résumé: Introduction: Cette étude s’intéresse à l’expérience de soins de patients aînés de 70 ans et plus atteints de cancer entourant une visite à l’urgence. Elle repose sur plusieurs résultats d’études démontrant que ces personnes présentent des besoins spécifiques non comblés, les amenant à utiliser les services d’urgence pour y répondre. Peu d’études se sont intéressées à leur expérience de soins et encore plus rarement dans le contexte d’une visite à l’urgence. But : Mieux comprendre l’expérience de soins des patients aînés atteints de cancer entourant une visite à l’urgence. Cette étude comprend quatre objectifs soit : 1) établir le profil des patients de 70 ans et plus ayant consulté l’urgence pour un problème lié à leur cancer dans les 12 mois précédant l’étude; 2) identifier les raisons et les facteurs amenant ces patients à consulter les services d’urgence; 3) identifier les stratégies de coping utilisées avant d’aller à l’urgence et 4) décrire l’expérience de soins de ces patients à l’urgence. Méthode: Une étude à devis mixte simultané a été entreprise. Une analyse descriptive des bases de données administratives a été réalisée pour documenter le profil sociodémographique, clinique et l'utilisation des services des patients aînés atteints de cancer de 70 ans et plus qui ont visité l'urgence d'un centre hospitalier au Québec, le Canada (n = 792, Objectifs 1-2). Ensuite, des entrevues semi-structurées ont suivi (n = 11) et ont été analysées par une analyse de contenu en profondeur (Objectifs 2, 3, & 4). Résultats: Un total de 792 patients aînés atteints de cancer ont visité l'urgence pour un total de 1572 visites. Les raisons de consultation les plus fréquentes étaient de nature respiratoire (15,8%), digestive (13,4%) et les troubles cardiovasculaires (8,2%). Plus de la moitié des visites était réalisée de jour. L’anxiété, les problèmes d’accessibilité et la détérioration importante de la santé étaient des facteurs qui influençaient le recours aux services d’urgence. Les patients ont été en mesure de déployer une multitude de stratégies de coping pour faire face à leurs problèmes de santé. Par ailleurs, l’expérience de soins est un processus unique, vécu de manière très individuelle. Conclusion: Cette étude décrit l’expérience de soins de patients aînés atteints de cancer à l’urgence et souligne plusieurs domaines d’amélioration des services en périphérie de l’urgence, mais aussi au sein même du service d’urgence. / Abstract: Introduction: Older cancer patients are known to have specific unmet needs due to the complexity of their health care, leading them to use emergency services. However, it is known that emergency rooms are not well-suited to the needs of the elderly. Few studies have focused on the health care experience of older cancer patients and even less so in the context of emergency room (ER) visits. Purpose: This study aims to better understand the experience of older cancer patients in the context of ER visits for unexpected health deterioration related to cancer. We sought to: 1) establish the profile of patients aged 70 years and older who made ER visits for problems related to their cancer in the 12 months preceding the study; 2) identify the reasons and factors that motivate older patients with cancer to make ER visits; 3) identify coping strategies used by older cancer patients prior to ER visits; and 4) describe the health care experience of older cancer patients in the context of ER visits. Methods: A concurrent mixed-method design was used. Descriptive analysis of administrative databases was first conducted to document the socio-demographic, clinical, and service utilization profile of elderly cancer patients aged 70 years and older who visited the ER of a hospital in Québec, Canada (n = 792, Objectives 1-2). Semi-structured interviews were subsequently conducted (n = 11) and then analysed using in-depth content analysis (Objectives 2, 3, & 4). Results: The sample of 792 older cancer patients made a total of 1,572 ER visits. The most frequent medical reasons for ER visits were respiratory (15.8%) and digestive (13.4%) concerns, and cardiovascular conditions (8.2%). Content analysis of the qualitative data suggested that older cancer patients made most of the ER visits when experiencing high levels of anxiety, when other cancer care services were unavailable, or because of a serious life-threatening health condition. Patients were able to use a variety of coping strategies to deal with health issues. Furthermore, the care process is experienced uniquely for each individual. Conclusion: This study describes the health care experience of older cancer patients in the context of ER visits and suggests areas of improvement both outside of and within emergency services.
1014

A psychometric profile of patients attending the Durban University of Technology Chiropractic Day Clinic with non-specific low back pain

Bramuzzo, Valentina January 2016 (has links)
Submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Department of Chiropractic, Durban University of Technology, Durban, South Africa, 2016. / BACKGROUND: Low back pain (LBP) is a major health problem and a leading cause of disability worldwide, accounting for numerous medical and chiropractic consultations. Risk factors for developing as well as perpetuating LBP have been recognised, including psychosocial factors and to a lesser extent organic diseases. There is good evidence for the role of biological, psychological, and social factors in the aetiology and prognosis of back pain. The biopsychosocial model developed by Waddell (1987) has become a dominant consideration in determining the aetiology and prognosis of back pain, and has led to the development and testing of many back pain care interventions. This includes a focus on identifying and treating ‘yellow flags’ which are psychosocial factors that may result in LBP becoming chronic, and incorporating the treatment of these ‘yellow flags’ as a component of LBP care. AIM: The aim of this study was to determine a psychometric profile of patients attending the Durban University of Technology (DUT) Chiropractic Day Clinic (CDC) with non-specific LBP using the Keele STarT Back Screening Tool (SBST) and Bournemouth Questionnaire (BQ). METHODOLOGY: Once ethical clearance was obtained to conduct the research study at the DUT CDC, all patients over the age of eighteen presenting to the DUT CDC with non-specific LBP as new patients, or as former or current patients presenting with non-specific LBP as a new complaint, were directly approached by the researcher. The prospective participants were asked a series of screening questions in order to ensure that they qualified for the study. A total of 132 participants completed an informed consent, a pre-validated questionnaire, the SBST and the BQ. The questionnaires took approximately ten to fifteen minutes to complete; participants were given the choice to complete them either before or after their appointment so as not to interrupt the treatment time. All informed consents and completed questionnaires were collected by the researcher and stored in separate sealed ballot boxes. All questionnaires were kept confidential and only seen by the researcher and supervisor. A code was allocated to each questionnaire before data was captured on a spreadsheet for data analysis. The IBM SPSS version 22 was used for data analysis by a biostatistician. RESULTS: A total of 132 questionnaires were utilised for statistical analysis. Based on the SBST, 47.7% (n = 63) of the total population (N = 132), had a low risk of developing chronic LBP, 28.8% (n = 38) had a medium risk of developing chronic LBP, and 23.5 % (n = 31) had a high risk of developing chronic LBP. The BQ indicated that 63.6% (n = 84) of the total population (N = 132) scored 35 or less and thus had a low risk of developing chronic LBP, while 36.4% (n = 48) scored above 35 and thus had a medium to high risk of developing chronic LBP. A very strong association was found between the SBST and BQ risk groups (p = <0.001). A total of 87.1% (n = 27) of the participants who had a high risk of chronicity according to the SBST (N = 31) also had a high risk of chronicity according to the BQ. The female gender, being a current smoker and partaking in little or no physical activity were found to be statistically significant risk factors for chronic LBP. CONCLUSION: The results in this study suggest that patients presenting to the DUT CDC supports the notion that chronic LBP is a multifactorial condition with significant psychosocial implications and should be approached as such. / M
1015

Evaluation of Health Data Warehousing: Development of a Framework and Assessment of Current Practices

Leenaerts, Marianne 09 April 2015 (has links)
If knowledge has been gathered by the practitioners’ community in the area of health data warehousing evaluation, it is mostly relying on anecdotal evidence instead of academic research. Isolated dimensions have received more attention and benefit from definitions and performance measures. However, very few cases can be found in the literature which describe how the assessment of the technology can be made, and these cases do not provide insight on how to systematize such assessment. The research in this dissertation is aimed at bridging this knowledge gap by developing an evaluation framework, and conducting an empirical study to further investigate the state of health data warehousing evaluation and the use of the technology to improve healthcare efficiency, as well as to compare these findings with the proposed framework. The empirical study involved an exploratory approach and used a qualitative method, i.e. audio-taped semi-structured interviews. The interviews were conducted in collaboration with the Healthcare Data Warehousing Association and involved 21 participants who were members of the Association working in a mid- to upper-level management capacity on the development and implementation of health data warehousing. All audio-taped interviews were transcribed and transcripts were coded using a qualitative analysis software package (NVivo, QSR International). Results were obtained in three areas. First, the study established that current health data warehousing systems are typically not formally evaluated. Systematic assessments relying on predetermined indicators and commonly accepted evaluation methods are very seldom performed and Critical Success Factors are not used as a reference to guide the system’s evaluation. This finding appears to explain why a literature review on the topic returns so few publications. Second, from patient throughput to productivity tracking and cost optimization, the study provided evidence of the contribution of data warehousing to the improvement of healthcare systems’ efficiency. Multiple examples were given by participants to illustrate the ways in which the technology contributed to streamlining the care process and increase healthcare efficiency in their respective organizations. Third, the study compared the proposed framework with current practices. Because formal evaluations were seldom performed, the empirical study offered limited feedback on the framework’s structure and rather informed its content and the assessment factors initially defined. / Graduate
1016

The effect of an exogenous fibrolytic enzyme on forage digestibility parameters

Goosen, Liezel 12 1900 (has links)
Thesis (MScAgric) -- Stellenbosch University, 2004. / ENGLISH ABSTRACT: The ruminant has the ability to utilize forages more efficiently than any other production animal. The utilization of forage fibre is an important aspect of ruminant production systems, as this is the main source of energy available to the animal. The availability of high-fibre forage nutrients is, however, restricted by cell wall degradability, and since low quality forages contribute a great deal to ruminant production systems worldwide, the improvement of this degradation process is of major economic importance. The use of exogenous fibre degrading enzymes has been proposed as a means of enhancing this process, with positive results being obtained from in vitro studies incorporating exogenous enzyme preparations. Positive in vivo results with regard to forage digestibility and other animal production parameters have consequently also been obtained following the addition of exogenous fibre-degrading enzyme preparations to the ruminant diet. Two initial screening experiments were undertaken in order to identify fungal enzyme preparations that may have a positive effect on in vitro fibre degradability. The initial screening employed an in vitro organic matter digestibility technique, and was successful in identifying at least six enzyme preparations displaying enhanced digestibility results that were statistically significant. A second in vitro gas production procedure was used to confirm results obtained from organic matter digestibility assays, as well as to increase screening capacity in order to evaluate new enzyme preparations more time-efficiently. Statistical analysis of results obtained from the secondary screening identified various enzyme candidates producing promising results. Only one of these, Abo 374, proved to be statistically superior to the control and other enzyme preparations. A growth trial was subsequently conducted to assess the performance of this enzyme in vivo. The trial involved individual feeding of 32 Dohne Merino ram lambs grouped according to weights into four groups consisting of 8 lambs each. Each group represented a specific application level of enzyme to the wheat straw component of a high fibre diet, amounting to 10, 5, or 1 ml enzyme supematant/kg straw. The enzyme was diluted with water at appropriate rates to obtain an application rate of 300ml/kg straw. The fourth (control) group was treated with water at the same application rate. The trial was conducted over a period of six weeks, during which feed intakes, weekly weight gains, as well as feed conversion efficiencies were recorded. Results suggested significant weight gains in the high (10ml/kg) and medium (5ml/kg) treatment groups, indicated by a P-value of 0.04. Similarly, feed conversion efficiencies were improved for above-mentioned groups (P=0.05), while feed intakes did not differ significantly between the four experimental groups. / AFRIKAANSE OPSOMMING: Die herkouer besit die vermoee om ruvoere beter as enige ander produksiedier te kan benut. Die gebruik van ruvoervesel is 'n belangrike aspek van herkouer produksiesisteme, aangesien ruvoere die hoof bron van energie aan die herkouer verskaf. Die beskikbaarheid van hoe-vesel ruvoer nutriente word egter beperk deur die degradeerbaarheid van die selwand, en aangesien lae kwaliteit ruvoere 'n groot bydrae tot wereldwye herkouer-produksiesisteme maak, is die moontlike verbetering van hierdie degraderingsproses van groot ekonomiese belang. In 'n poging om hierdie verteringsproses te help bevoordeel, is die gebruik van eksogene veselverterende ensieme ondersoek, en positiewe resultate is verkry wanneer hierdie ensieme in in vitro studies gebruik is. Goeie verbeterings ten opsigte van ruvoer verteerbaarheid en ander diereproduksie parameters is ook verkry deur middel van in vivo studies waar eksogene ensieme by die ruvoer van herkouers gevoeg IS. Twee eksperimente is ondemeem in 'n poging om ensiempreparate wat 'n moontlike positiewe effek op in vitro veselvertering mag he, te identifiseer. Die eerste, 'n in vitro organiese materiaal verteerbaarheid tegniek, was suksesvol in die identifisering van minstens ses ensiem preparate wat statisties betekenisvolle verbeterings ten opsigte van verteringsresultate geproduseer het. 'n Tweede in vitro gasproduksie prosedure is vervolgens gebruik om resultate verkry vanaf die eerste tegniek, te bevestig, asook om evalueringskapasiteit te vergroot en sodoende, nuwe ensiempreparate meer tydseffektief te evalueer. Statistiese evaluering van resultate verkry uit die tweede in vitro tegniek het 'n reeks ensieme met positiewe resultate opgelewer. Een van hierdie, Ab0374, het statisties betekenisvolle resultate ten opsigte van die kontrole, sowel as ander ensieme getoon. In 'n volgende eksperiment is 'n groeiproef gedoen om die effektiwiteit van hierdie ensiem in vivo te toets. In die proef is 32 Dohne Merino ramlammers op grond van hul gewig in vier groepe van agt skape elk verdeel, en individueel gevoer. Die groepe het verskillende toedieningsvlakke van die toetsensiem, toegedien tot die koringstrooi komponent van 'n hoe-vesel dieet, ontvang. Toedieningsvlakke was 10, 5, of lml ensiemkonsentraat/kg strooi. Elke groep se ensiemkonsentraat is verdun met die toepaslike hoeveelheid water om 'n toedieningsvlak van 300ml ensiemoplossing/kg koringstrooi te verkry. 'n Vierde groep is behandel slegs met water teen dieselfde toedieningsvlak, en het gedien as 'n kontrole. Die eksperiment is oor 'n periode van 6 weke uitgevoer. Tydens die proeftydperk is voerinnames, weeklikse gewigstoenames, sowel as voeromsetverhoudings, gedokumenteer. Resultate het betekenisvolle gewigstoenames in die hoe (lOml/kg) en medium (5ml/kg) groepe opgelewer, aangedui deur 'n P-waarde van 0.04. Voeromsetverhoudinge het ook verbeteringe getoon vir bogenoemde twee groepe (P=0.05), terwyl voerinnames nie merkbaar tussen die vier groepe verskil het nie.
1017

A genetic analysis of biological and economic efficiency of post-weaning feedlot performance in beef cattle

Van der Westhuizen, Robert Rolfe 03 1900 (has links)
Thesis (PhD (Agric))--University of Stellenbosch, 2005. / ENGLISH ABSTRACT: It is generally accepted that feed intake and growth (gain) are the most important economic components when calculating profitability in a growth test or feedlot. Feeding cost of animals is a major determinant of profitability in livestock production enterprises. Genetic selection to improve feed efficiency aims to reduce the cost of feeding in beef cattle production and thereby improve profitability. The objective of this study was to define a clear selection objective to enable South African beef breeders and especially the feedlot industry to select for post-weaning growth or feedlot performance and to identify factors influencing profitability in a feedlot environment. Because of the recording of individual feed intake and weight gain values in the South African Agricultural Research Councils' centralized growth tests, it was also possible to calculate a phenotypic value for feedlot profitability (R-value) for each bull tested in a centralized growth test. (Co)variances, using multitrait as well as random regression models, for and between feedlot profitability, weaning weight and other production, reproduction and efficiency traits were estimated. Residual feed intake (RFI) and feed conversion ratio (FCR) as efficiency traits were also compared to growth (average daily gain (ADG), weaning weight (WW) and shoulder height (SHD)), reproductive (scrotum circumference (SCR)) and profitability (feedlot profitability) traits measured in growth tests of young Bonsmara bulls. Consequently, a single post-weaning growth selection index value based on the economic and breeding values of different selection criteria related to feedlot profitability was composed. (Co)variance components, heritabilities and genetic correlations for and between initial weight (lW), final weight (FW), total feed intake (FI) and shoulder height (SHD) were estimated through the use of multitrait restricted maximum likelihood (REML) procedures. These breeding values (EBV s) were then used in a selection index to calculate a single economical value for each animal. This economical value is an indication of the gross profitability value or gross test value (GTV) of the animal in a post-weaning growth test. The heritability estimate of 0.36 for R-value, obtained from the multitrait analysis, shows that this trait is genetically inherited and that it can be selected for. The heritability for R-value obtained from the single trait random regression model varied between 0.57 and 0.62. The genetic correlations between the R-value and the other traits, obtained from the multitrait analysis, varied from negligible to high. The heritability estimated for FCR was 0.34 and for RFl 0.31 with a genetic correlation estimate of 0.75 between the traits. The estimated genetic correlation between profitability (R-value) and FCR and RFl were -0.92 and -0.59, respectively. The genetic correlation estimate of -0.92 between FCR and R-value is largely due to the part-whole relationship between these two traits. This is also shown in their genetic trends. The genetic correlations and expected correlated responses between RFl and FCR with R-value suggest that indirect selection for R-value through the direct selection for FCR and/or RFl will result in slower genetic progress in Rvalue than direct selection for R-value. However, where the R-value cannot be calculated and/or where direct selection for R-value is not possible, it would be better to select indirectly for R-value through the use of FCR rather than RF!. Consequently, a regression equation was developed (with an R2 of 0.82) to estimate a feed intake value for all performance-tested Bonsmara bulls which were group fed and whose feed intakes were unknown. These predicted feed intake values made it possible to calculate a feedlot or post-weaning growth profitability value (R-value) for all tested bulls even where individual feed intakes were unknown. Subsequently, an R-value for each bull was calculated in a favourable economic environment (FEE), an average economic environment (AEE) and in an unfavourable economic environment (VEE). The high Pearson and Spearman correlations between the EBV s based on AEE and the other two environments suggested that the average economic environment could be used to calculate EBVs for R-value or feedlot growth profitability. It is therefore not necessary to change the carcass, weaner or feed price on a regular basis to account for possible re-rankings based on R-value EBVs. Heritabilities for lW, FW, Fl and SHD were 0.41, 0.40, 0.33 and 0.51, respectively. The highest genetic correlations between these traits were the 0.78 (between lW and FW) and 0.70 (between Fl and FW). GTV values varied between -R192.l7 and R231.38, with an average of R9.31. The Pearson correlations between EBVs (for production and efficiency traits) and GTV range from -0.51 to 0.68. The lowest correlation (closest to zero) was 0.26 between the Kleiber ratio (KLB) and GTV. Correlations of 0.68 and -0.51 were estimated between average daily gain (ADG) and GTV and feed conversion ratio (FCR) and GTV, respectively. The heritabilities of the different traits included in the selection index suggest that it is possible to select for a GTV. The selection index can benefit feedlotting In selecting offspring of bulls with high GTV values to maximize profitability. The Pearson and Spearman correlations between the R-value EBVs and the index values (GTV) were very high (0.97). This high correlation of 97% indicates that it is not important which method is used to calculate a genetic post-weaning growth of feedlot profitability value. The selection index value is, however, more simplified than the feedlot profitability with less assumption. Therefore, it is recommended that the post-weaning selection index value be used as a selection objective in breeding programmes to improve post-weaning growth profitability rather than the more complex feedlot profitability value. / AFRIKAANSE OPSOMMING: 'N GENETIESE ANALIESE VAN DIE BIOLOGIESE EN EKONOMIESE DOELTREFFENTHEID VAN NASPEENSE GROEI IN VLEISBEESTE IN DIE VOERKRAAL: Dit word algemeen aanvaar dat voerinname en groei die twee ekonomies mees belangrike komponente in die berekening van 'n naspeense groei- of voerkraalwinsgewindheidswaarde is. Voerkostes is 'n bepalende faktor van winsgewindheid in enige lewendehawe boerderypraktyk. Seleksie om voerdoeltreffendheid te verbeter, verminder dus die voerkostes in vleisbeesproduksie en gevolglik 'n verhoging in die winsgewindheid. Die doelwit van die studie was om faktore te identifiseer wat 'n invloed op winsgewindheid in die voerkraaiomgewing het asook om 'n duidelike seleksiedoelwit te formuleer wat die Suid- Afrikaanse vleisbeesteiers en veral die voerkraalbedryf instaat sal kan stelom vir naspeense groeidoeltreffendheid ofvoerkraalwinsgewindheid te selekteer. As gevolg van die aantekening en rekordhouding van weeklikse individuele voennnames en gewigstoenames van alle prestasiegetoetsde bulle, in 'n gesentraliseerde groeitoets deur die Suid- Afrikaanse Landbou Navorsingsraad getoets, was dit moontlik om vir elk van hierdie bulle 'n fenotipiese voerkraalwinsgewindheidswaarde (R-waarde) te kon bereken. (Ko)variansies is vir en tussen voerkraalwinsgewindheid, speengewig en ander produksie-, reproduksie- en doeltreffendheidseienskappe bereken deur van meereienskap en ewekansige regressie modelle gebruik te maak. Twee doeltreffendheidseienskappe naamlik residuele voerinname (RFI) en voeromsetverhouding (FCR) is ook met groei (gemiddelde daaglikse toename (ADG), speengewig (WW) en skouerhoogte (SHD)), reproduksie (skrotumomvang (SCR)) en winsgewindheidseienskappe (voerkraalwinsgewindheid (R-waarde)) vergelyk, om sodoende te bepaal watter een die mees geskikte eienskap is om indirek vir voerkraalwinsgewindheid of groei, gebaseer op teeltwaardes en ekonomiese waardes vir die verskillende eienskappe, wat 'n invloed op naspeense groei winsgewindheid het, gestruktueer. (Ko)variansiekomponente, oorerflikhede en genetiese korrelasies vir en tussen begingewig (lW), eindgewig (FW), voerinname (FI) en skouerhoogte (SHD) is bereken deur van 'n meereienskap (REML) ontleding gebruik te maak. Hierdie teelwaardes (EBVs) is vervolgens in 'n seleksie-indeks gebruik om 'n enkele ekonomies of voerkraal-winsgewindheids seleksie-indekswaarde (GTV) vir elke dier te bereken. Hierdie ekonomiese waarde is 'n aanduiding van die bruto winsgewindheidswaarde ofbruto toetswaarde (GTV) van die dier in 'n naspeentoets. Die oorerflikheid, vanuit die meereienskapontleding vir R-waarde beraam, was 0.36. Hierdie oorerflikheid dui daarop dat die eienskap oorerflik is en dat dit wel moontlik is om daarvoor te selekteer. Die ooreflikhede van R-waarde, voorspel vanuit die enkeleienskap ewekansige regressieontleding varieer tussen 0.57 en 0.62. Die genetiese korrelasie tussen R-waarde en ander eienskappe, vanuit die meereienskap ontleding beraam, varieer tussen weglaatbaar klein tot hoog. Die oorerflikheid van FeR was 0.34 en van RFI 0.31 met 'n genetiese korrelasie van 0.75 tussen die twee eienskappe. Die genetiese korrelasie tussen R-waarde en FeR, en R-waarde en RFI was onderskeidelik -0.92 en -0.59. Die rede vir die hoë negatiewe genetiese korrelasie tussen R-waarde en FeR van -0.92 is omdat dieselfde komponente in die berekening van die twee eienskappe gebruik is. Dit word ook in die genetiese tendense weerspeël. Die genetiese korrelasies en verwagte gekorreleerde responsies tussen R-waarde en FeR, en tussen R-waarde en RFI dui daarop dat stadiger genetiese vordering verkry sal word in R-waarde deur direkte seleksie vir beide FeR en RFI as wat verkry sal word deur die direkte seleksie vir R-waarde. Wanneer 'n R-waarde egter nie bereken kan word nie of waar dit nie moontlik is om direk vir R-waarde te selekteer nie, sal vinniger genetiese vordering in R-waarde gemaak word deur die direkte seleksie vir FeR as vir RF!. 'n Regressievergelyking is geformuleer (met 'n R2 van 0.82) om vir alle prestasiegetoetsde bulle, waar bulle in 'n groep gevoer is en individuele voerinnames onbekend is, 'n voerinnamewaarde te voorspel. Hierdie voorspelde voerinnames maak dit moontlik om vir elke prestasiegetoetsde bul ,'n naspeengroei- of voerkraalwinswaarde (R-waarde) te bereken, al is hulle individuele voerinnames onbekend. Vervolgens is drie verskillende R-waarde vir vleisproduksie vir elke bul bereken naamlik, in 'n gunstige ekonomiese omgewing (FEE), 'n gemiddelde ekonomiese omgewing (AEE) en 'n ongunstige ekonomiese omgewing (VEE). Die hoë Pearson en Spearman korrelasies tussen die EBVs vir R-waarde, bereken in die AEE en die EBVs in die ander twee ekonomiese omgewings, dui daarop dat die AEE gebruik kan word om EBVs vir naspeense groeiof voerkraalwins te bereken. Dit is dus nie nodig om op 'n gereelde grondslag die karkasprys, lewendige speenkalfprys of die voerprys te verander nie. Oorerflikhede, vanuit die meereienskap ontledings VIr lW, FW, FI en SHD verkry, was onderskeidelik 0.41, 0.40, 0.33 en 0.51. Die hoogste genetiese korrelasies tussen die eienskappe was 0.78 tussen lW en FW en 0.70 tussen FI en FW. GTV indekswaardes varieer tussen -Rl92.17 en R231.38 met 'n gemiddelde waarde van R9.31. Die Pearson korrelasies tussen die EBVs van produksie- en doeltreffenheidseienskappe en GTV het tussen -0.51 en 0.68 gevarieer. Die korrelasie naaste aan zero, van 0.26, was die korrelasie tussen GTV en die Kleiber-verhouding. Die korrelasies tussen GTV en ADG, en GTV en FeR was onderskeidelik 0.68 en -0.51. Die oorerflikhede van die verskillende eienskappe wat in die seleksie-indeks ingesluit is, dui daarop dat die indekswaarde weloorerflik is en dat seleksie hiervoor wel moontlik is. Hierdie indekswaarde kan deur die voerkraaiindustrie gebruik word om nageslag van diere met hoë GTV waardes te selekteer om sodoende maksimum wins uit die voerkraai te genereer. Die Pearson en Spearman korrelasies tussen R-waarde EBVs en die indekswaardes (GTV) was besonder hoog (0.97). Hierdie hoë korrelasie dui daarop dat dit geen verskil sal maak watter een van die twee metodes gebruik word in die berekeninge van 'n naspeense groei- of voerkraalwinswaarde nie. Die seleksie-indeks metode is egter minder gekompliseerd met minder aannames as in die geval van die rekeningkundige fenotipiese benadering (R-waarde). As gevolg hiervan, word die naspeense seleksie-indeks waardes (GTV) aanbeveel om te gebruik as 'n teeldoelwit in telingsprogramme om naspeense groei- of voerkraaiwins geneties te verbeter, eerder as die meer gekompliseerde fenotipiese voerkraaiwins (R-waardes) metode.
1018

Breeding for Nitrogen Use Efficiency in Soft Red Winter Wheat

Hitz, Katlyn 01 January 2015 (has links)
Nitrogen use efficient (NUE) wheat varieties have potential to reduce input costs for growers, limit N runoff into water ways, and increase wheat adaptability to warmer environments. Previous studies have done little to explain the genetic basis for NUE and components, nitrogen uptake efficiency (NUpE) and nitrogen utilization efficiency (NUtE). Four studies were conducted to 1) determine genotypic stability of NUE under high and low N regimes and under warming 2) determine effect of warming on NUE 3) indentify QTL associated with NUE components 4) assess the utility of canopy spectral reflectance (CSR) as a high-throughput phenotyping device for NUE. Genotypic response to N stress or warming varied. Uptake efficiency was found to be more important than utilization efficiency to genotypic performance under high and low N environments and under warming. Selection under low N for NUpE and under high N for NUtE most efficiently identified NUE varieties. Uptake and utilization were lower under warming due to quickened development. No strong correlations between the CSR indices and NUE existed. No QTL were found to be significantly associated with NUE components. Further research into the mechanisms controlling NUE and to reveal plant response to N stress and under warming is necessary.
1019

Integreringsanalys av robot och arbetsstation på ITT Water & Wastewater

Arnesson, Fredrik January 2010 (has links)
<p>ITT Water & Wastewater ställer höga krav på kostnadseffektiv produktion vilket är en starkt bidragande orsak till att företaget är världsledande på sin marknad. För att erhålla kostnadseffektiv produktion har kombinationen människa robot visat sig vara framgångsrik.</p><p>Examensarbetets syfte var att ta fram underlag åt ITT Water & Wastewater för att ta beslut om frigörande av indirekt personal vid line 15:s isoleringsstation på Elmotorverkstaden. Syftets uppfyllande stöttades av de underbyggande syftena att försöka höja robotens utnyttjandegrad samt reducera isoleringsmaskinens omställningstid.</p><p>Arbetet bygger på kvalitativa och kvantitativa data i form av mätningar, intervjuer och egna observationer. Med stöd av erhållen data lyftes fyra olika förslag fram. Förslagen understryktes bland annat av integrering av arbetsmoment, förhöjd automatiseringsgrad och outsourcing.</p> / <p>ITT Water & Wastewater place high demands on cost-effective production which is a major contributing factor to the company enact as a world leader in its market. In order to obtain cost-effective production, the combination man robot proved to be successful.</p><p>The thesis purpose was to provide data for ITT Water & Wastewater to take decisions concerning the release of indirect staff in line 15´s isolation station at the electric motor workshop. The purpose of the implement supported by the reinforced purposes to increase the utilization of the robot and reduce the adaptation time at the isolation machine.</p><p>The work builds on qualitative and quantitative data in the shape of measurements, interviews and own observations. On the reliance of data four different suggestions were presented. The suggestions emphasized among integration of working moment, increased automation level and outsourcing.</p>
1020

Part I. - The Comparative Nutritive Value of Certain Locally Produced Poultry Rations, Part II. - Confinement Rearing

Hinds, H. B. 08 1900 (has links)
No description available.

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