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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

Understanding the genetic basis of C4 photosynthesis through breeding

Reeves, Gregory January 2019 (has links)
No description available.
122

Avaliação da qualidade de vida e funcionalidade em pacientes com doença arterial coronariana submetidos à revascularização cirúrgica ou angioplastia /

Freschi, Larissa. January 2011 (has links)
Resumo: A doença arterial coronariana (DAC) é uma das principais causas de óbito e de perda de qualidade de vida ao longo do tempo. Seu tratamento pode ser clínico ou por meio de técnicas como a angioplastia percutânea ou a revascularização cirúrgica do miocárdio. Multidimensional, a DAC exerce fortes impactos físicos, emocionais e sociais. Por isso, além das avaliações clínicas, são indispensáveis as informações sobre a qualidade de vida e funcionalidade dos pacientes para uma análise mais precisa de suas condições após o tratamento. O objetivo deste estudo foi avaliar a percepção da qualidade de vida e a funcionalidade em pacientes com DAC nos momentos antes da revascularização cirúrgica ou da angioplastia, na alta hospitalar e 60 dias após a intervenção. Foram avaliados 90 pacientes divididos em grupos por procedimento. Utilizou-se uma ficha com perfil demográfico, questionário genérico de avaliação da qualidade de vida "The Medical Study 36-item Short-Form Health Survey" (SF-36) e escala de "Medida de Independência Funcional" (MIF). Observou-se, no perfil demográfico, a predominância do gênero masculino (58,9%), escolaridade com o ensino fundamental incompleto (64,4%) e índice de massa corporal (IMC) acima do ideal (37,8% sobrepeso e 25,6% obesidade). O grupo de angioplastia apresentou os melhores escores de qualidade de vida antes do procedimento nos domínios "aspectos físicos", "dor", "vitalidade", "aspectos sociais" e na questão de avaliação da saúde anterior. Na alta isso se manteve com o acréscimo do domínio "capacidade funcional". No momento 60 dias após o procedimento, a angioplastia obteve melhores escores em "aspectos físicos" e "aspectos sociais". Na comparação entre os momentos, os domínios "capacidade funcional" e "dor" pioraram na alta para o grupo cirurgia, e melhoraram após 60 dias... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Coronary artery disease (CAD) is a leading cause of death and loss of quality of life over time. The treatment is clinical in early stages of disease or the technique is percutaneous angioplasty or coronary artery bypass grafting. The DAC is a multidimensional disease, which has strong physical, emotional and social impacts. Besides to clinical assessments, information about the quality of life and functionality of patients are essential for a more precise analysis of their condition after treatment. The aim of this study was to evaluate the perceived quality of life and functionality in patients with CAD in the moments before surgical revascularization or angioplasty, at discharge and 60 days after the intervention. We evaluated 90 patients divided into groups by procedure. We used a form with demographic profile, generic questionnaire for assessing quality of life "The Medical Study 36-item Short-Form Health Survey (SF-36) and scale of" Functional Independence Measure (FIM). It was observed in the demographic, the predominance of males (58.9%), schooling and incomplete primary education (64.4%) and body mass index (BMI) above the ideal (37.8% overweight and 25.6% obese). The angioplasty group had the best scores of quality of life before the procedure in the domains "physical aspects", "pain," "vitality" and "social aspects" and the issue of evaluation of previous health. These results remained at hospital discharge with the addition of domain "functional capacity". At present 60 days after the procedure, angioplasty had higher scores in "physical aspects" and "social aspects". Comparing the times, the domains "physical functioning" and "pain" got worse at the group of discharge for surgery and improved after 60 days for both groups. In the domains "general health" and "vitality", both groups improved in the third stage of evaluation. Angioplasty only group showed improvement... (Complete abstract click electronic access below) / Orientador: Marcos Augusto de Moraes Silva / Coorientador: Juliana Bassalobre Carvalho Borges / Banca: Antonio Sérgio Martins / Banca: Reinaldo Ayer de Oliveira / Mestre
123

Functional and rheological properties of Bambara groundnut starch-catechin complex obtained by chemical grafting

Gulu, Nontobeko Benhilda January 2018 (has links)
Thesis (MTech (Food Technology))--Cape Peninsula University of Technology, 2018. / The aim of this study was to produce Bambara groundnut (BGN) starch-catechin complex using chemical initiators (ascorbic acid and hydrogen peroxide) and cyclodextrin (alpha and beta) with the view to obtain a functional ingredient for the food industry. BGN starch was successfully extracted from BGN flour through dry milling method, yielding 32% of BGN starch. Native BGN starch was chemically modified using ascorbic acid (1% w/w) and hydrogen peroxide (165% w/w) as redox, biocompatible initiator for grafting catechin to the BGN starch. In addition, cyclodextrin (alpha and beta) were also used as initiators for modifying BGN starch through complexation methods. Complexation methods used included the microwave, co-evaporation and kneading. The characterization of native and modified BGN starches was carried out by performing scanning electron microscopy, powder X-ray diffraction, Fourier Transform Infrared (FTIR) and fluorescence spectroscopy analysis. Functional, thermal and rheological properties of native and modified BGN starches were evaluated. The pasting properties of BGN starches were determined using the Rapid Visco Analyser (RVA). According to the SEM profile, native BGN starch had round, oval and elliptical shapes typical for legume starches. Native BGN starch displayed a typical type-C crystallinity which is common among legumes with strong peaks at 2θ of 15o, 17o and 23o. BGN starches modified through complexation methods had sharper peaks indicating an increase in starch crystallinity; however, following chemical modification there was loss in starch crystallinity which was evidenced by the amorphous region in the chemically modified BGN starches. Structure of native and modified BGN starches was confirmed by FTIR. The FTIR spectra of native BGN starch showed variable peaks at 3285.34 cm-1, 2931.69 cm-1, 1634.36 cm-1, 1336.77 cm-1 which are attributed to OH stretching, C-H stretching, water bending vibrations and C-O stretching, respectively. Furthermore, the FTIR results confirmed that native BGN starch is made up of glucose molecules just like all other starches. All modified BGN starches displayed a new absorption peak at 1020 cm-1 wavelength, thus indicating that starch modification was successful. On the other hand, all BGN starch-catechin complexes displayed a new absorption peak in the range of 1520 -1560 cm-1, attributed to the C-C stretching within the aromatic ring of the catechin. The successful grafting of catechin to BGN starch was also confirmed by the fluorescence spectroscopy results, where all the BGN starch-catechin complexes had an emission peak at 320 nm while native BGN starch had an emission peak at 270 nm. Antioxidant capacity of BGN starch was determined through DPPH and ORAC antioxidant assays. Within the DPPH assay, the antioxidant activity ranged from 2.26 to 38.31 μmol TE/g. The antioxidant activity of modified BGN starch-catechin complexes was significantly (p ≤ 0.05) higher than the ones modified without catechin. On the other hand, within the ORAC assay, the antioxidant activity ranged from 0.07 to 126.71 μmol TE/g. As opposed to the results obtained in DPPH assay, the antioxidant activity of chemically modified BGN starch-catechin complexes was significantly (p ≤ 0.05) higher than that of complexed BGN starch-catechin complexes. Chemical modification significantly increased the swelling capacity of native BGN starch while complexation methods significantly reduced it.
124

The Effects of Rootstock, Scion, Grafting Method and Plant Growth Regulators on Flexural Strength and Hydraulic Resistance of Apple

Adams, Stuart W. 01 December 2016 (has links)
The apple rootstock ‘Geneva® 41’ (‘G.41’), is desirable for its resistance to fire blight, Erwinia amylovora, while producing high yields. However, ‘G.41’ and other Geneva® selections tend to form weak graft unions in the nursery that are susceptible to breaking in the wind, at harvest, or during shipment. In order to understand and remedy this graft union weakness, six scions (‘Fuji’, ‘Gala’, ‘Honeycrisp’, ‘McIntosh’, ‘Pink Lady’, and ‘Scilate’) by seven rootstocks (‘G.41’, ‘G.935’, ‘G.214’, ‘G.11’, ‘M.9-NIC 29’, ‘B.9’ and ‘EMLA 26’), by two grafting methods (chip bud and saddle graft) in a factorial design were tested for graft union flexural strength and flexibility. Additionally, plant growth regulators (PGR) were applied to trees with ‘G.41’ as rootstock as a solution to overcome graft union weakness. Transpiration rate and hydraulic resistance were measured for comparison of a weak graft forming rootstock (‘G.41’) to a strong graft forming rootstock (‘M.9-NIC 29’). ‘G.41’ consistently formed a weaker graft union regardless of scion or grafting method. Scions such as ‘McIntosh’ and ‘Pink Lady’ formed stronger graft unions, while ‘Scilate’ and ‘Honeycrisp’ form weaker graft unions. Saddle grafting did not improve graft union strength. Nurseries that graft on ‘G.41’ should choose scions that form stronger graft unions. Benzyl adenine (BA) in a latex paint increased the strength and flexibility of the graft union relative to scion cross sectional area (SCSA), but further research is needs to identify more efficient methods of application. Rootstock effect on transpiration rate was different between years. No detectable differences were found for hydraulic resistance through the graft union of different rootstocks, suggesting weaker graft unions did not limit hydraulic conductance or transpiration rate. Thus graft union weakness is not an indicator of poor vascular connection.
125

Surface grafting of polymers via living radical polymerization techniques; polymeric supports for combinatorial chemistry

Zwaneveld, Nikolas Anton Amadeus, Chemical Engineering & Industrial Chemistry, UNSW January 2006 (has links)
The use of living radical polymerization methods has shown significant potential to control grafting of polymers from inert polymeric substrates. The objective of this thesis is to create advanced substrates for use in combinatorial chemistry applications through the use of g-radiation as a radical source, and the use of RAFT, ATRP and RATRP living radical techniques to control grafting polymerization. The substrates grafted were polypropylene SynPhase lanterns from Mimotopes and are intended to be used as supports for combinatorial chemistry. ATRP was used to graft polymers to SynPhase lanterns using a technique where the lantern was functionalized by exposing the lanterns to gamma-radiation from a 60Co radiation source in the presence of carbon tetra-bromide, producing short chain polystyrene tethered bromine atoms, and also with CBr4 directly functionalizing the surface. Styrene was then grafted off these lanterns using ATRP. MMA was graft to the surface of SynPhase lanterns, using g-radiation initiated RATRP at room temperature. It was found that the addition of the thermal initiator, AIBN, successfully increased the concentration of radicals to a level where we could achieve proper control of the polymerization. RAFT was used to successfully control the grafting of styrene, acrylic acid and N,N???-dimethylacrylamide to polypropylene SynPhase Lanterns via a -initiated RAFT agent mediated free radical polymerization process using cumyl phenyldithioacetate and cumyl dithiobenzoate RAFT agents. Amphiphilic brush copolymers were produced with a novel combined RAFT and ATRP system. Polystyrene-co-poly(vinylbenzyl chloride) created using gamma-radiation and controlled with the RAFT agent PEPDA was used as a backbone. The VBC moieties were then used as initiator sites for the ATRP grafting of t-BA to give a P(t-BA) brush that was then hydrolyzed to produce a PAA brush polymer. FMOC loading tests were conducted on all these lanterns to assess their effectiveness as combinatorial chemistry supports. It was found that the loading could be controlled by adjusting the graft ratio of the lanterns and had a comparable loading to those commercially produced by Mimotopes.
126

In vitro and in vivo bone formation - assessment and application

Chen, Jinbiao, Prince of Wales Clinical School, UNSW January 2006 (has links)
Background: Bone-grafting materials are required in orthopaedic surgery to treat bone defects. Bone formation assessment is required for the development of new strategies and approaches and for quality assurance and quality control of currently available materials. Approaches to the assessment of bone formation are yet to be systematically established, quantified and standardized. Aims: the overall aim of this study was to establish a set of comprehensive quantitative approaches for the assessment of bone formation and to evaluate the role of osteoblastic cells, growth factors, and scaffolds on this process. Materials & methods: both in vitro and in vivo parameters for osteoblast phenotype and bone formation were tested in osteosarcoma cell lines, Saos-2 and U2OS cells, mesenchymal cell line, C2C12 cells, primary adipose derived stromal cells (ADSCs), platelet rich plasma (PRP), and morselized bone grafts. The in vitro parameters used were measurement of alkaline phosphatase (ALP) activity, detection of bone nodules and biomineralization, and quantification of immunocytochemistry and conventional RT-PCR of osteoblast genotyping. In vivo parameters involved ectopic bone formation in nude mice and nude rats and a tibial defect model in nude rats. Histomorphometric and quantitative immunohistochemical analyses were also performed. Results: The in vitro characterization and ectopic bone formation capabiltity of Saos-2 and U2OS cells have been established. Saos-2 cell line, which presents many osteoblast genotype and phenotype, is a stable positive control for both in vitro and in vivo bone formation assessments. The measurement of ALP activity in both solid and liquid phases has been standardized. Both the genotype and phenotype of osteoblast lineage cells has been quantitatively assessed during the capability testing of ADSCs and PRP. Quantitative assessment of new bone formation and related protein markers in vivo has been successfully established through the testing of the biological properties of gamma irradiated morselized bone grafts. Conclusion: A comprehensive knowledge of the assessment of bone regeneration and formation in vitro and in vivo has been integrated and developed through years of study. A whole set of in vitro and in vivo approaches for the assessment of bone formation has been modified and standardized to best suit the different clinical applications. This thesis provides an outline of both in vitro and in vivo bone formation assessment and their clinical applications.
127

Considering the evidence : what counts as the best evidence for the post harvest management of split thickness skin graft donor sites? / Richard John Wiechula.

Wiechula, Rick. January 2004 (has links)
"May 2004" / Bibliography: leaves 172-184. / xvi, 186 leaves : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (D.Nurs.)--University of Adelaide, Dept. of Clinical Nursing, 2004
128

Surface grafting of polymers via living radical polymerization techniques; polymeric supports for combinatorial chemistry

Zwaneveld, Nikolas Anton Amadeus, Chemical Engineering & Industrial Chemistry, UNSW January 2006 (has links)
The use of living radical polymerization methods has shown significant potential to control grafting of polymers from inert polymeric substrates. The objective of this thesis is to create advanced substrates for use in combinatorial chemistry applications through the use of g-radiation as a radical source, and the use of RAFT, ATRP and RATRP living radical techniques to control grafting polymerization. The substrates grafted were polypropylene SynPhase lanterns from Mimotopes and are intended to be used as supports for combinatorial chemistry. ATRP was used to graft polymers to SynPhase lanterns using a technique where the lantern was functionalized by exposing the lanterns to gamma-radiation from a 60Co radiation source in the presence of carbon tetra-bromide, producing short chain polystyrene tethered bromine atoms, and also with CBr4 directly functionalizing the surface. Styrene was then grafted off these lanterns using ATRP. MMA was graft to the surface of SynPhase lanterns, using g-radiation initiated RATRP at room temperature. It was found that the addition of the thermal initiator, AIBN, successfully increased the concentration of radicals to a level where we could achieve proper control of the polymerization. RAFT was used to successfully control the grafting of styrene, acrylic acid and N,N???-dimethylacrylamide to polypropylene SynPhase Lanterns via a -initiated RAFT agent mediated free radical polymerization process using cumyl phenyldithioacetate and cumyl dithiobenzoate RAFT agents. Amphiphilic brush copolymers were produced with a novel combined RAFT and ATRP system. Polystyrene-co-poly(vinylbenzyl chloride) created using gamma-radiation and controlled with the RAFT agent PEPDA was used as a backbone. The VBC moieties were then used as initiator sites for the ATRP grafting of t-BA to give a P(t-BA) brush that was then hydrolyzed to produce a PAA brush polymer. FMOC loading tests were conducted on all these lanterns to assess their effectiveness as combinatorial chemistry supports. It was found that the loading could be controlled by adjusting the graft ratio of the lanterns and had a comparable loading to those commercially produced by Mimotopes.
129

Surface grafting of polymers via living radical polymerization techniques; polymeric supports for combinatorial chemistry

Zwaneveld, Nikolas Anton Amadeus, Chemical Engineering & Industrial Chemistry, UNSW January 2006 (has links)
The use of living radical polymerization methods has shown significant potential to control grafting of polymers from inert polymeric substrates. The objective of this thesis is to create advanced substrates for use in combinatorial chemistry applications through the use of g-radiation as a radical source, and the use of RAFT, ATRP and RATRP living radical techniques to control grafting polymerization. The substrates grafted were polypropylene SynPhase lanterns from Mimotopes and are intended to be used as supports for combinatorial chemistry. ATRP was used to graft polymers to SynPhase lanterns using a technique where the lantern was functionalized by exposing the lanterns to gamma-radiation from a 60Co radiation source in the presence of carbon tetra-bromide, producing short chain polystyrene tethered bromine atoms, and also with CBr4 directly functionalizing the surface. Styrene was then grafted off these lanterns using ATRP. MMA was graft to the surface of SynPhase lanterns, using g-radiation initiated RATRP at room temperature. It was found that the addition of the thermal initiator, AIBN, successfully increased the concentration of radicals to a level where we could achieve proper control of the polymerization. RAFT was used to successfully control the grafting of styrene, acrylic acid and N,N???-dimethylacrylamide to polypropylene SynPhase Lanterns via a -initiated RAFT agent mediated free radical polymerization process using cumyl phenyldithioacetate and cumyl dithiobenzoate RAFT agents. Amphiphilic brush copolymers were produced with a novel combined RAFT and ATRP system. Polystyrene-co-poly(vinylbenzyl chloride) created using gamma-radiation and controlled with the RAFT agent PEPDA was used as a backbone. The VBC moieties were then used as initiator sites for the ATRP grafting of t-BA to give a P(t-BA) brush that was then hydrolyzed to produce a PAA brush polymer. FMOC loading tests were conducted on all these lanterns to assess their effectiveness as combinatorial chemistry supports. It was found that the loading could be controlled by adjusting the graft ratio of the lanterns and had a comparable loading to those commercially produced by Mimotopes.
130

Ring-opening polymerization from cellulose for biocomposite applications

Lönnberg, Hanna January 2009 (has links)
There is an emerging interest in the development of sustainable materials with high performance. Cellulose is promising in this regard as it is a renewablere source with high specific properties, which can be utilized as strong reinforcements in novel biocomposites. However, to fully exploit the potential ofcellulose, its inherent hydrophilic character has to be modified in order toimprove the compatibility and interfacial adhesion with the more hydrophobicpolymer matrices commonly used in composites.In this study, the grafting of poly(ε-caprolactone) (PCL) and poly(L-lactide)(PLLA) from cellulose surfaces, via ring-opening polymerization (ROP) of ε-caprolactone and L-lactide, was investigated. Both macroscopic and nano-sizedcellulose were explored, such as filter paper, microfibrillated cellulose (MFC),MFC-films, and regenerated cellulose spheres. It was found that thehydrophobicity of the cellulose surfaces increased with longer graft lengths, andthat polymer grafting rendered a smoother surface morphology.To improve the grafting efficiency in the ROP from filter paper, both covalent(bis(methylol)propionic acid, bis-MPA) and physical pretreatment (xyloglucanbisMPA)were explored. The highest grafting efficiency was obtained with ROPfrom the bis-MPA modified filter papers, which significantly increased amountof polymer on the surface, i.e. the thickness of the grafted polymer layer.MFC was grafted with PCL to different molecular weights. The dispersability innon-polar solvent was obviously improved for the PCL grafted MFC, incomparison to neat MFC, and the stability of the MFC suspensions was better maintained with longer grafts. PCL based biocomposites were prepared from neat MFC and PCL grafted MFCwith different graft lengths. The polymer grafting improved the mechanical properties of the composites, and the best reinforcing effect was obtained when PCL grafted MFC with the longest grafts were used as reinforcement.A bilayer laminate consisting of PCL and MFC-films grafted with different PCL graft lengths displayed a gradual increase in the interfacial adhesion with increasing graft length.The effect of grafting on the adhesion was also investigated via colloidal probeatomic force microscopy at different temperatures and time in contact. A significant improvement in the adhesion was observed after polymer grafting. / QC 20100730

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