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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.
121

Estudo genético da deposição de gordura abdominal e de características de desempenho, carcaça e composição corporal em linhagem macho de frangos de corte. / Genetic study of abdominal fat deposition and performance, carcass and body composition traits in a male broiler line.

Gaya, Leila de Genova 27 January 2004 (has links)
O presente trabalho teve como objetivo estimar parâmetros genéticos e fenotípicos do peso da gordura abdominal e de características de desempenho, carcaça e composição corporal em uma linhagem macho de frangos de corte fornecida pela Agroceres Ross Melhoramento de Aves S. A. As aves faziam parte do programa denominado sib test, ou teste de irmãos, onde são coletadas informações de carcaça dos irmãos dos indivíduos a serem selecionados, estes chamados de rebanho elite. 30273 informações de granja das aves elite e de seus irmãos foram concedidas pela Empresa e 6167 dados de abatedouro dos irmãos das aves elite foram coletados. As características analisadas foram: peso à seleção (PS), medidas de ultra-sonografia do músculo peitoral (US1 e US2), conversão alimentar (CA), eficiência alimentar (EA), ingestão (ING), peso vivo (PV), peso eviscerado (PE), peso do peito (PPEI), peso de pernas (PPER), rendimento de carcaça (RCAR), rendimento de peito (RPEI), rendimento de pernas (RPER), peso da gordura abdominal (PGA), peso do coração (PC), peso da moela (PM), peso do fígado (PF), peso do intestino (PI), escore do coração (ESCC) e escore do fígado (ESCF). Os componentes de (co) variância foram estimados por verossimilhança restrita, utilizando-se o programa MTDFREML. As estimativas de herdabilidade foram em sua maioria moderadas, sendo alta para peso da gordura abdominal, o que sugere que esta característica é passível de seleção. As correlações genéticas e fenotípicas variaram de acordo com as características analisadas. / This research was conducted to estimate genetic and phenotypic parameters of abdominal fat and performance, carcass and body composition traits in a male broiler line provided by Agroceres Ross Melhoramento de Aves S. A. The broilers belonged to sib test program, in which data from brothers and sisters of the individuals to be selected, called elite flock, are collected. 30273 farm data of chicken from elite flock and their sibs were conceded by the Company and 6167 processing data from sibs of elite flock were collected. The traits analyzed were: body weight at juvenile selection (PS), ultrasound records of pectoral muscle (US1 e US2), feed conversion ratio (CA), feed efficiency (EA), feed intake (ING), live weight at processing (PV), carcass weight (PE), breast weight (PPEI), leg weight (PPER), carcass yield (RCAR), breast yield (RPEI), leg yield (RPER), abdominal fat weight (PGA), heart weight (PC), gizzard weight (PM), liver weight (PF), intestine weight (PI), heart score (ESCC) and liver score (ESCF). (Co) variance components were estimated by restricted maximum likelihood method, using the software MTDFREML. Heritability coefficients estimated were mostly moderate, and the heritability of abdominal fat weight was high, which suggests that this trait can be selected. Genetic and phenotypic correlations coefficients estimated varied according to the trait studied.
122

Pressure sensitive textiles for integration in saddle pads

ENGVALL, THERESE January 2013 (has links)
: In this thesis, capacitive textile pressure sensors have been developed. The sensors were meant to be integrated into saddle pads and be able to measure the pressure between the saddle and horse. The aim of the thesis was to create a theoretical and practical based map on how a textile pressure sensor can be made. Capacitance was found to be the most suitable pressure sensitive technique to be implemented in a textile structure. The project was divided into two cycles, where the first cycle consisted of laminating capacitive textile pressure sensors of readymade fabrics in different thicknesses and sizes. After testing the pressure sensitivity of these laminates, it was concluded that a thin fabric with some compressibility was sufficient for making a textile capacitive pressure sensor. However, the area cannot be too small. The second cycle consisted of weaving capacitive pressure sensors as three layer structures. The pressure sensitivity of the sensors and the effect of moisture were tested. The results showed that most of the woven sensors were able to sense a 50g change in weight even after a 700g load was put on. The moisture and water tests showed that the pressure sensors must be protected from water and moisture. It was also discovered that there is a lack of knowledge in how textile structures and fibres behave under compression and release. Models of how textiles behave during pressure are needed to do correct transformations between compression and pressure and predict how the textile will behave during different pressures. / Program: Masterutbildning i textilteknik
123

Caracteriza??o da pr?polis verde brasileira: subst?ncias fen?licas, atividade biol?gica e an?lise quimiom?trica / Characterization of brazilian green propolis: phenolics compounds, biological activity and chemometric analysis

SALGUEIRO, Fernanda Barbosa 23 September 2016 (has links)
Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Propolis is a resinous material collected by bees from different parts of plants. Both its composition as its biological properties are dependent on factors such as climate, soil, vegetation and species of collecting bees. Propolis has great potential for therapeutic use due to its chemical composition and pharmacological properties. Herein it was determined the contents of phenolic compounds, antioxidant capacity and chemical composition (assessed by HPLC-PAD) of twelve green propolis samples from beekeepers and sixteen commercial propolis extracs from different regions of Southeast Brazil. The antioxidant abilities of the extracts were qualitatively determined through the total phenolic contents using the Folin?Ciocalteau method. Total flavonoids were assessed by the method of complexation with aluminium chloride. The quantitative antioxidant activiti of propolis extracts were determined both by trapping the organic radicals DPPH and ABTS.+ as well by the iron reduction method (FRAP). High pressure liquid chromatography allowed the identification and quantification of chlorogenic acid, caffeic acid, ferulic acid, para-coumaric acid, rosmarinic acid, vanillin, hesperidin, naringenin, pinobanksin, kaempferol, 4-hydroxy-3,5-diprenyl cinnamic acid (Artepillin-C), kampheride and pinostrobin. Artepillin C, a well known chemical marker of propolis, was present in all propolis extracts analyzed. We highlight that the presence of rosmarinic acid in propolis samples from Rio de Janeiro was reported for the first time in this work. The discrimination between green propolis in natura and commercial green propolis extracts was performed using PCA (Principal Component Analysis) statistical method. The antioxidant capacity in vivo of propolis extracts were evaluated using Saccharomyces cerevisiae as biological system model, assessing important parameters as stress tolerance and lipid peroxidation rate. The antifungal activity of ethanol extracts of propolis in natura were tested against the phytopathogenic fungus Fusarium oxysporium. / A pr?polis ? um material resinoso coletado pelas abelhas de diferentes partes das plantas, sua composi??o e as suas propriedades biol?gicas dependem do clima, solo, vegeta??o e da esp?cie da abelha. A pr?polis tem grande potencial de aplica??o terap?utica, devido ? sua composi??o e propriedades farmacol?gicas. Nesse trabalho foi determinado o teor de subst?ncias fen?licas, a capacidade antioxidante e composi??o qu?mica por CLAE-DAD de doze amostras de pr?polis verde, adquiridas de apicultores, e dezesseis extratos de pr?polis comerciais, provenientes de diferentes regi?es do Sudeste do Brasil. A capacidade antioxidante dos extratos foi avaliada qualitativamente atrav?s do teor de fen?licos totais, pelo m?todo de Folin?Ciocalteau, e flavonoides pelo m?todo de complexa??o com cloreto de alum?nio. A quantifica??o do potencial antioxidante foi realizada pela captura dos radicais org?nicos DPPH e ABTS.+, al?m do m?todo de redu??o do ?on f?rrico (FRAP). An?lises por cromatografia l?quida de alta efici?ncia permitiram a identifica??o e quantifica??o de ?cido clorog?nico, ?cido cafeico, ?cido fer?lico, ?cido para-cum?rico, ?cido rosmar?nico, ?cido 3,5-diprenil-4-hidroxicin?mico (Artepillin C), vanilina, hesperidina, naringenina, pinobanksina, canferol, canferide e pinostrobina. Em todos os extratos de pr?polis analisados foi identificado o Artepillin C, marcador qu?mico para pr?polis verde. Destacamos que neste trabalho foi reportada pela primeira vez a presen?a de ?cido rosmar?nico em pr?polis do Rio de Janeiro. M?todos quimiom?tricos de an?lise explorat?ria, utilizando ?nalise por Componentes Principais foram utilizados para discriminar extratos de pr?polis verde in natura daqueles extratos comerciais. O potencial antioxidante in vivo dos extratos etan?licos de pr?polis foram avaliados utilizando cepas controles de Saccharomyces cerevisiae como modelo de sistema biol?gico e foram avaliados toler?ncia ao estresse e proxida??o lip?dica. A atividade antif?ngica dos extratos etan?licos de pr?polis in natura foram avaliados, e inibiram o crescimento in vitro do fungo fitopat?geno Fusarium oxysporum.
124

Processing, Reliability And Integration Issues In Chemical Mechanical Planarization

Zantye, Parshuram B 15 July 2005 (has links)
Global planarization is one of the major demands of the semiconductor industry. Chemical mechanical polishing (CMP) is the planarization method of choice use to achieve the required stringent tolerances essential for successful fabrication of next generation Integrated Circuits (IC). The predominant reason for CMP defects is the shear and normal stresses during polishing to which the material is subjected. Understanding the process of CMP and factor that contribute to overall stress addition during polishing requires an approach that encompasses all the four major categories of variables, namely: a) machine parameters, b) material properties, c) polishing pad characteristics, and d) polishing slurry performance. In this research, we studied the utilized in-situ technique involving acoustic emission (AE) signal monitoring and coefficient of friction (COF) monitoring using a CETRTM Bench Top CMP Tester to evaluate the impact of variation in machine parameters on the CMP process. The mechanical and tribological properties of different candidate materials have been evaluated bring potential challenges in their integration to the fore. The study also involves destructive and non destructive testing of polishing pads performed for characterization and optimization of polishing pad architecture. Finally, the investigation concludes proposing novel nanoparticle CMP slurry which has a predominant chemical component in its polishing mechanism. It was found that the decrease in the mechanical shear and normal loading by: a) operating the process in the low stress regime, b) using potential materials that are mechanically stronger, c) using polishing pads with lesser variation in specific gravity and with a surface that is has its mechanical properties fine tuned to those of the wafer, and d) deploying polishing slurry with a significant chemical component mechanical removal, are some of the approaches that can be employed to meet the future challenges of the CMP process and reduce the defect associated with it.
125

Rotordynamic and thermal analyses of compliant flexure pivot tilting pad gas bearings

Sim, Kyu-Ho 15 May 2009 (has links)
Rotordynamic and thermal analyses of compliant flexure pivot tilting pad gas bearings were performed. First, compliant flexure pivot tilting pad gas bearings with pad radial compliance (CFTPBs) were introduced and designed for high-speed oil-free micro turbomachinery. The pad radial compliance was for accommodation of large rotor growth at high speeds. Parametric studies on pivot offset, preload, and tilting stiffness were performed using non-linear orbit simulations and coast-down simulations for an optimum design. Second, coast-down tests for imbalance response and stability of typical rotor-bearing system with a rigid rotor and two CFTPBs designed from the above design studies were conducted over operating speeds up to 55 krpm. Prediction of synchronous rotordynamic responses was made in terms of critical speed for various imbalance modes by using a rotordynamic analysis software (XLTRC), combined with dynamic force coefficients from the perturbation analysis. For stability analyses, a generalized orbit simulation program was developed considering both the translational and angular rotor motions with two different bearings. Linear stability analyses for the conical vibration mode were also performed by using XLTRC and the perturbation analysis based on the Lund method. Predictions of whirl speed showed good agreement to the tests, but the estimated onset speed of instability appeared lower than the measured instability. Finally, a new thermo-hydrodynamic analysis model of a typical rotor-bearing system with CFTPBs was presented, accompanying linear perturbation analyses to investigate thermal effects on the rotordynamic performance. A numerical procedure was established for solving the generalized Reynolds equation, the 3-D energy equation, and the associated boundary conditions at the pad inlet flow and solid walls (rotor and pad) simultaneously. Parametric studies were conducted on nominal clearance and external load. Nominal clearance showed significant influence on temperature fields, and external load had uneven thermal effects among pads. Case studies with heat flux and temperature boundary conditions on the rotor end surface were performed to simulate various working conditions of the bearing. Large rotor thermal growth due to the high rotor temperature showed noticeable influence on rotordynamic performance by increasing direct stiffness and damping coefficients.
126

Rotordynamic and thermal analyses of compliant flexure pivot tilting pad gas bearings

Sim, Kyu-Ho 15 May 2009 (has links)
Rotordynamic and thermal analyses of compliant flexure pivot tilting pad gas bearings were performed. First, compliant flexure pivot tilting pad gas bearings with pad radial compliance (CFTPBs) were introduced and designed for high-speed oil-free micro turbomachinery. The pad radial compliance was for accommodation of large rotor growth at high speeds. Parametric studies on pivot offset, preload, and tilting stiffness were performed using non-linear orbit simulations and coast-down simulations for an optimum design. Second, coast-down tests for imbalance response and stability of typical rotor-bearing system with a rigid rotor and two CFTPBs designed from the above design studies were conducted over operating speeds up to 55 krpm. Prediction of synchronous rotordynamic responses was made in terms of critical speed for various imbalance modes by using a rotordynamic analysis software (XLTRC), combined with dynamic force coefficients from the perturbation analysis. For stability analyses, a generalized orbit simulation program was developed considering both the translational and angular rotor motions with two different bearings. Linear stability analyses for the conical vibration mode were also performed by using XLTRC and the perturbation analysis based on the Lund method. Predictions of whirl speed showed good agreement to the tests, but the estimated onset speed of instability appeared lower than the measured instability. Finally, a new thermo-hydrodynamic analysis model of a typical rotor-bearing system with CFTPBs was presented, accompanying linear perturbation analyses to investigate thermal effects on the rotordynamic performance. A numerical procedure was established for solving the generalized Reynolds equation, the 3-D energy equation, and the associated boundary conditions at the pad inlet flow and solid walls (rotor and pad) simultaneously. Parametric studies were conducted on nominal clearance and external load. Nominal clearance showed significant influence on temperature fields, and external load had uneven thermal effects among pads. Case studies with heat flux and temperature boundary conditions on the rotor end surface were performed to simulate various working conditions of the bearing. Large rotor thermal growth due to the high rotor temperature showed noticeable influence on rotordynamic performance by increasing direct stiffness and damping coefficients.
127

Automatic Parallel Memory Address Generation for Parallel DSP Computing

Dai, Jiehua January 2008 (has links)
<p>The concept of Parallel Vector (scratch pad) Memories (PVM) was introduced as one solution for Parallel Computing in DSP, which can provides parallel memory addressing efficiently with minimum latency. The parallel programming more efficient by using the parallel addressing generator for parallel vector memory (PVM) proposed in this thesis. However, without hiding complexities by cache, the cost of programming is high. To minimize the programming cost, automatic parallel memory address generation is needed to hide the complexities of memory access.</p><p>This thesis investigates methods for implementing conflict-free vector addressing algorithms on a parallel hardware structure. In particular, match vector addressing requirements extracted from the behaviour model to a prepared parallel memory addressing template, in order to supply data in parallel from the main memory to the on-chip vector memory.</p><p>According to the template and usage of the main and on-chip parallel vector memory, models for data pre-allocation and permutation in scratch pad memories of ASIP can be decided and configured. By exposing the parallel memory access of source code, the memory access flow graph (MFG) will be generated. Then MFG will be used combined with hardware information to match templates in the template library. When it is matched with one template, suited permutation equation will be gained, and the permutation table that include target addresses for data pre-allocation and permutation is created. Thus it is possible to automatically generate memory address for parallel memory accesses.</p><p>A tool for achieving the goal mentioned above is created, Permutator, which is implemented in C++ combined with XML. Memory access coding template is selected, as a result that permutation formulas are specified. And then PVM address table could be generated to make the data pre-allocation, so that efficient parallel memory access is possible.</p><p>The result shows that the memory access complexities is hiden by using Permutator, so that the programming cost is reduced.It works well in the context that each algorithm with its related hardware information is corresponding to a template case, so that extra memory cost is eliminated.</p>
128

Comparison of Visual vs. Microscopic Methods to Detect Blood Splatter from an Intravascular Catheter with Engineered Sharps Injury Protection (ESIP)

Ansari, Aiysha R. 01 January 2012 (has links)
Intravascular devices with engineered sharps injury protection (ESIP) are designed to reduce sharps injuries, but have not been investigated for blood splatter potential. In this laboratory-based experiment, which did not use human subjects, 100 intravenous catheters of the same type with a retraction mechanism, were tested for blood splatter. Once blood was obtained from a simulated brachial vein containing mock venous blood, the devices were placed in a testing chamber and scientific filters labeled A, B & C were used to capture blood splatter after activation. The blood splatter was examined visually and microscopically, and the filters were weighed pre- and post-activation on an analytical scale. The research questions in this study were: 1) do retractable intravenous devices produce blood splatter, and 2) does blood splatter frequency differ between visual methods vs. microscopy? The differences in filter mass, visual inspection, and microscopic analysis for presence of blood on filters were the units of analysis. Descriptive statistics, paired t-tests to determine pre and post activation filter weights and kappa statistics to assess degree of agreement between methods were used to analyze the data. For filters B and C, the proportions with blood detected by the naked eye were 12 and 13% respectively. However, for filter A, both visual and microscopic methods detected blood splatter on 70% and 71% of the time respectively. In addition, a statistically significant difference was observed in the mean mass of filter A between pre- and post-activation confirmed by the naked eye (t= - 0.0013, p= 0.01400) and confirmed microscopically (t= - 0.00014, p=0.0092). Substantial agreement between methods was observed for filter A (kappa=0.78; 95% CI: 0.64-0.92), filter B (kappa= 0.73; 95% CI: 0.51-0.95) and filter C (kappa= 0.75; 95% CI: 0.55-0.96). However, in 7 instances (7%), blood was detected by microscopy but not by the naked eye on filters A (5 %), B (1%), and C (1%), respectively. Also, in 6 instances (6%), blood was detected by the naked eye but now by microscopy on filter B (3%), and filter C (3%). Consequently, there is potential for a total of 13 % blood splatter. The findings indicate potential for bloodborne pathogen exposure with use of a specific retractable intravascular catheter. The finding that blood splatter was detected by microscopy in 7% of the instances has important occupational health implications. Healthcare workers (HCWs) may not be able to detect this blood splatter when it occurs and may not report a splash to mucous membranes or non-intact skin. This study therefore reinforces the need for HCWs to wear personal protective equipment, such as masks, face shields, goggles, when using intravascular catheters with retractable mechanisms. It is recommended that the research protocol used in this study be replicated by other investigators and tested on all brands of retractable intravascular devices.
129

A holistic view of urinary stress incontinence in women

Berglund, Anna-Lena January 1995 (has links)
The present study group consists of 45 women with genuine stress incontinence who were selected for surgical treatment and randomized either to retropubic urethrocystopexy (n=30) or pubococcygeal repair (n=15). The preoperative assessment included medical history, gynecological examination, urine analysis and culture, residual urine, pad test, frequency-continence charts, water urethrocystoscopy, continence test and cystometry with analysis of micturition. Moreover, five semistructured interviews were performed with the women and two with their partner. The following questionnaires were used measuring a) personality characteristics: Karolinska Scales of Personality (KSP), Eysenck Personality Inventory (EPI), b) depression: Beck Depression Inventory (BDI) and c) social support: Interview Schedule for Social Interaction (ISSI). The results have shown that there was no difference in the subjective cure rate between the two surgical methods (73% vs. 80 % respectively). The bladder volume had increased in both groups and the intravesical pressure of the bladder filled to maximum had increased in the pubococcygeal repair group. Other urodynamic variables were unchanged by the operation. Pad tests have demonstrated that 67 % of the women in the urethrocystopexy group and 47 % in the pubococcygeal repair group ceased to leak urine. Postoperatively, 63 % of the women in the urethrocystopexy group needed high doses of analgesics compared with only 33 % in the pubococcygeal repair group. Among the women experiencing severe to very severe pain dysphoric subjects were overrepresented. Postoperative residual urine was a minor nursing problem in both groups. Women with SUI of long duration scored significantly higher than controls on the KSP scales of somatic anxiety, psychic anxiety, psychasthenia, suspicion and on the EPI lie-scale. There was no significant difference in sexual activity before and after surgery. One or two sexual dysfunctions within the desire, excitement, orgasmic and resolution phase were reported by the majority of women both before and after surgical intervention. The cured women reported a higher level of overall activities before surgery than the improved (i.e. not cured) women, whereas post surgery both the cured and the improved women obtained about the same level of activities. Regarding social support, no differences between the cured or improved women occured as concerns attachment. The cured women showed a higher degree of adequacy of social integration compared with the improved women. In order to delineate predictive factors for the surgical outcome the following variables were investigated: age of patient, duration of urine leakage, parity, personality, psychological and social factors. The following predictors of the outcome of surgical treatment emerged: duration of stress incontinence, neuroticism and age of patient. The results of the present study indicate the ecessity of a multidisciplinary approach to the treatment and nursing of women with SUI. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1995</p> / digitalisering@umu
130

Estudo genético da deposição de gordura abdominal e de características de desempenho, carcaça e composição corporal em linhagem macho de frangos de corte. / Genetic study of abdominal fat deposition and performance, carcass and body composition traits in a male broiler line.

Leila de Genova Gaya 27 January 2004 (has links)
O presente trabalho teve como objetivo estimar parâmetros genéticos e fenotípicos do peso da gordura abdominal e de características de desempenho, carcaça e composição corporal em uma linhagem macho de frangos de corte fornecida pela Agroceres Ross Melhoramento de Aves S. A. As aves faziam parte do programa denominado sib test, ou teste de irmãos, onde são coletadas informações de carcaça dos irmãos dos indivíduos a serem selecionados, estes chamados de rebanho elite. 30273 informações de granja das aves elite e de seus irmãos foram concedidas pela Empresa e 6167 dados de abatedouro dos irmãos das aves elite foram coletados. As características analisadas foram: peso à seleção (PS), medidas de ultra-sonografia do músculo peitoral (US1 e US2), conversão alimentar (CA), eficiência alimentar (EA), ingestão (ING), peso vivo (PV), peso eviscerado (PE), peso do peito (PPEI), peso de pernas (PPER), rendimento de carcaça (RCAR), rendimento de peito (RPEI), rendimento de pernas (RPER), peso da gordura abdominal (PGA), peso do coração (PC), peso da moela (PM), peso do fígado (PF), peso do intestino (PI), escore do coração (ESCC) e escore do fígado (ESCF). Os componentes de (co) variância foram estimados por verossimilhança restrita, utilizando-se o programa MTDFREML. As estimativas de herdabilidade foram em sua maioria moderadas, sendo alta para peso da gordura abdominal, o que sugere que esta característica é passível de seleção. As correlações genéticas e fenotípicas variaram de acordo com as características analisadas. / This research was conducted to estimate genetic and phenotypic parameters of abdominal fat and performance, carcass and body composition traits in a male broiler line provided by Agroceres Ross Melhoramento de Aves S. A. The broilers belonged to sib test program, in which data from brothers and sisters of the individuals to be selected, called elite flock, are collected. 30273 farm data of chicken from elite flock and their sibs were conceded by the Company and 6167 processing data from sibs of elite flock were collected. The traits analyzed were: body weight at juvenile selection (PS), ultrasound records of pectoral muscle (US1 e US2), feed conversion ratio (CA), feed efficiency (EA), feed intake (ING), live weight at processing (PV), carcass weight (PE), breast weight (PPEI), leg weight (PPER), carcass yield (RCAR), breast yield (RPEI), leg yield (RPER), abdominal fat weight (PGA), heart weight (PC), gizzard weight (PM), liver weight (PF), intestine weight (PI), heart score (ESCC) and liver score (ESCF). (Co) variance components were estimated by restricted maximum likelihood method, using the software MTDFREML. Heritability coefficients estimated were mostly moderate, and the heritability of abdominal fat weight was high, which suggests that this trait can be selected. Genetic and phenotypic correlations coefficients estimated varied according to the trait studied.

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