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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.
601

Muscle damage and adaptation in response to plyometric jumping

Isaacs, Ashwin Wayne 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The aim of the study was to investigate skeletal muscle changes induced by an acute bout of plyometric exercise before and after plyometric training. The study consisted of an acute study and training intervention study. The acute study, investigated whether direct evidence of ultrastructural damage and identification of indirect factors were more evident in subjects presenting with rhabdomyolysis. Moreover the training intervention study investigated whether plyometric training would protect the muscle from ultrastructural damage and rhabdomyolysis. During the acute intervention, twenty six healthy untrained individuals completed an acute bout of plyometric exercise (10 x 10 squat-jumps, 1 min rest). After, thirteen subjects continued with the training intervention. Eight of these subjects completed 8 weeks of plyometric jump training, while five subjects were instructed to rest from physical activity for 8 weeks. Seven days after the final training session the training and rest group repeated a second acute bout of plyometric exercise. Acute Study: Creatine kinase (CK) activity increased significantly following the single bout of plyometric exercise in all subjects (baseline: 129 to day 4: 5348 U/l). This was accompanied by an increase in perceived pain, C-reactive protein (CRP) a marker of inflammation as well as white blood cells (WBCs). Electron micrographs of muscle biopsies taken 3 days post exercise showed evidence of ultrasructural damage and membrane damage was apparent by immunofluorescence by the loss of dystrophin staining. A stretch of the c-terminus of titin was observed by immunogold, and western blot analysis indicated an increase in calpain-3 autolysis. Based on individual CK responses (CK range: 153-71,024 U/L at 4days after exercise) the twenty six subjects were divided into two groups, namely the high (n=10) and low responders (n=16). Training intervention: Following training the trained group did not experience: a rise of CK activity (110.0 U/l), perceived pain, CRP, WBCs, Z-line streaming, a stretch of titin or calpain-3 activation; while in the control group only two subjects presented with Z-line streaming. The results indicate that high responders have a more pronounced inflammatory response compared to low responders after eccentric exercise, therefore more WBCs and more specifically neutrophils are recruited to damaged areas resulting in greater membrane damage by respiratory burst in high responders. This damage can be limited with training by remodelling sarcomeric proteins via calpain activation resulting in the stable assembly of proteins in the sarcomere preventing the release of proteins. / AFRIKAANSE OPSOMMING: Die doel van die studie was om skeletspier veranderinge wat teweeggebring is deur voor en na afloop van akute pleometriese oefening, te ondersoek. Die studie bestaan uit ‘n akute intervensie en ‘n oefeningsintervensie gedeelte. Die akute intervensie het ondersoek ingestel na die direkte bewyse van ultrastrukturele skade en identifikasie van indirekte faktore meer sigbaar is in proefpersone wat met rhabdomiolose presenteer. Meerso het die oefningsintervensie die moontlikheid dat pleometriese oefening die spier van ultrastrukturele skade en rhabdomiolose beskerm, ondersoek. Tydens die akute intervensie is 26 gesonde ongeoefende individue die akute pleometriese oefeningsessie (10 x 10 hurkspronge, 1 min rus) voltooi. Hierna het 13 proefpersone voortgegaan met die oefeningsintervensie. Agt van hierdie proefpersone het agt weke pleometriese sprongsessie oefeninge voltooi, terwyl vyf proefpersone gevra is om vir 8 weke geen oefeninge te doen nie. Sewe dae na afloop van die finale oefeningssessie het die oefening en kontrole groep in ‘n tweede herhaalde akute pleometriese oefeningsessie deelgeneem. Akute intervensie: kreatienkinase (KK) aktiwiteit het betekenisvol verhoog na die enkel pleometriese oefeningsessie in all proefpersone (basislyn: 129 tot op dag vier: 5348 U/l). Hierdie is vergesel met ‘n toename in die persepsie van pyn, c-reaktiewe proteïen (CRP) ‘n merker van inflammasie sowel as witbloedselle (WBS). Elektronmikrograwe van spierbiopsies wat geneem is drie dae na afloop van die oefeninge, het tekens van ultrastrukturele skade en membraanskade getoon wat ook deur immunofluoresensie duidelik warneembaar was deur die verlies van distrofienverkleuring. ‘n Verrekking van die c-terminus van titin is ook waargeneem deur middel van immunogold. Westernblot analyse het ‘n toename in calpain-3 outolise getoon. Gegrond op individuele KK response (KK grense: 153-71,024 U/L na vier dae post oefening) is 26 proefpersone verdeel in twee groepe naamlik ‘n hoë (n=10) en lae responders (n=16). Oefeningintervensie:: Na oefening het die geoefende groep nie ‘n toename in KK aktiwiteit getoon nie (KK aktiwiteit (110.0 U/l)), pynervaring, CRP, WBS, Z-lynstroming, ‘n strekking van titin of calpain-3 aktivering; terwyl in die kontrole groep daar slegs twee proefpersone met Z-lynstroming geïdentifiseer is. Die resultate wyse daarop dat hoë responders ‘n meer uitgesproke inflammatoriese reaksie toon vergeleke met die lae responders na afloop van essentriese oefening. Daar word dus meer WBS en spesifiek meer neutrofiele na beskadigde areas gelokaliseer wat in grootter membraanskade deur respiratoriese inspanning in die hoë responders. Hierdie skade kan beperk word deur oefening waardeur hermodulering van sarkomeriese proteïene via calpain aktivering tot stabiele rangskiking van proteïene in die sarcomere lei en daardeur proteïen vrystelling verhinder. / The NRF for financial assistance
602

Effect of pleistocene climatic changes on the evolutionary history of South African intertidal gastropods

Muteveri, Tinashe 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Historical vicariant processes due to glaciations, resulting from the large-scale environmental changes during the Pleistocene (0.012-2.6 million years ago, Mya), have had significant impacts on the geographic distribution of species, especially also in marine systems. The motivation for this study was to provide novel information that would enhance ongoing efforts to understand the patterns of biodiversity on the South African coast and to infer the abiotic processes that played a role in shaping the evolution of taxa confined to this region. The principal objective of this study was to explore the effect of Pleistocene climate changes on South Africa′s marine biodiversity using five intertidal gastropods (comprising four rocky shore species Turbo sarmaticus, Oxystele sinensis, Oxystele tigrina, Oxystele variegata, and one sandy shore species Bullia rhodostoma) as indicator species. Sequence data obtained from partial segments of the mitochondrial cytochrome oxidase c subunit 1 (COI), and the nuclear ribosomal DNA (encompassing part of 5.8S, second Internal Transcribed Spacer and part of 28S, hereinafter called ITS2; or comprising part of the first Internal Transcribed Spacer, 5.8S, second Internal Transcribed Spacer and part of 28S, hereinafter called ITS), were used as genetic markers to construct phylogeographic patterns and to investigate demographic histories of the taxa. Population structure was investigated using haplotype network analyses, pairwise ΦST statistics, analysis of molecular variance (AMOVA), isolation by distance analyses, Bayesian analysis of population structure (BAPS) and coalescent analysis of gene flow. Demographic history was analysed through Fu′s Fs tests, mismatch distributions, and Bayesian skyline plots. Demographic analyses suggest that all five intertidal gastropods studied experienced demographic expansions dating to the late Pleistocene. The sandy shore direct developer B. rhodostoma began expansion after the LGM (c. 15 kya) whereas for the four rocky shore broadcast spawners (T. sarmaticus, O. sinensis, O. tigrina, and O. variegata) the onset of expansion coincided with or preceded the LGM (c. 25, 60, 50, 40 kya, respectively). Consistent with recent range expansions and gene flow patterns, the population genetic structure in all species was characterised by shallow or a lack of population differentiation. Oxystele variegata was an exception as it showed a deep disjunction, of late Pleistocene origin, between individuals in the west coast Namaqua Bioregion and those in the south coast Agulhas Bioregion. These results provide strong evidence of the vital role that Pleistocene climatic changes and current regimes played in shaping the nature and distribution of biodiversity on the South African coast. In addition, gene flow in all species, except O. tigrina, was remarkably asymmetrical with the regions around Cape Infanta and Port Elizabeth acting as source populations. Considering the generally weak population genetic structure and gene flow patterns detected for most gastropod species studied here, it is recommended that T. sarmaticus, O. sinensis, O. tigrina and B. rhodostoma be managed as panmictic populations, and that the region encompassing Cape Infanta, and Port Elizabeth should be prioritised for conservation as it appears to harbour source populations. Oxystele variegata was the only species showing distinct population structure and in this instance, species specific conservation efforts should recognize this divergence by treating the two genetic assemblages as distinct management units. / AFRIKAANSE OPSOMMING: Historiese vikariante prosesse kan toegeskryf word aan glasiasie, en het tot gevolg gehad dat grootskaalse veranderinge in die omgewing plaasgevind het tydens die Pleistoseen (,012 - 2.6 miljoen jaar gelede, Mjg). Dit het 'n beduidende impak gehad op die geografiese verspreiding van spesies, veral ook in die mariene stelsels. Die motivering vir hierdie studie was om nuwe data te voorsien wat sal bydrae tot die voortgesette pogings om die patrone van biodiversiteit langs die Suid-Afrikaanse kus te verstaan. Dit sou ook help om die abiotiese prosesse af te lei wat 'n rol gespeel het in die evolusie van taksa wat in hierdie streek voorkom. Die hoofdoel van hierdie studie was om die effek van die Pleistoseen klimaatsveranderinge op Suid-Afrika se mariene biodiversiteit te bepaal deur gebruik te maak van vyf intergety slak spesies as indikatore (vier wat in rotsagtige gebiede voorkom: Turbo sarmaticus, Oxystele sinensis, Oxystele tigrina, Oxystele variegata en 'n sanderige strand spesies: Bullia rhodostoma). Volgorde data verkry vanaf gedeeltelike segmente van die mitochondriale sitochroom oksidase c subeenheid 1 (COI), en die kern ribosomale DNA (bestaande uit 'n deel van 5.8S, tweede interne getranskribeerde spasieërders en 'n deel van 28S), hierna genoem ITS2 is gebruik as genetiese merkers om filogeografiese patrone te dokumenteer en ook om die demografiese geskiedenis van die spesies te ondersoek. Bevolking struktuur is ondersoek deur gebruik te maak van haplotipe netwerk analise, paarsgewyse ΦST statistiek, analise van molekulêre variansie (AMOVA), isolasie deur afstand analise, Bayesiaanse analise van die bevolking struktuur (BAPS) en analise van gene vloei. Demografiese geskiedenis is ontleed deur Fu se Fs toetse, misparing verdelings, en Bayesiaanse luglyn kurwes. Demografiese ontleding dui daarop dat al vyf die intergety slakke wat ondersoek is demografiese uitbreidings ervaar het wat terugdateer tot die einde van die Pleistoseen. Die sanderige strand direkte ontwikkelaar, B. rhodostoma, het die uitbreiding begin na die LGM (c. 15 Kya), terwyl vir die vier rotsagtige kusbewoners wat eiers oor 'n uitgebreide gebiede versprei (T. sarmaticus, O. sinensis, O. tigrina, en O. variegata) het die aanvang van die bevolkings uitbreiding saamgeval met die laaste galsiasie of dit voorafgegaan (c. 25, 60, 50, 40 Kya, onderskeidelik). In ooreenstemming met die onlangse reeks bevolkings uitbreidings, is die bevolking genetiese struktuur in alle spesies gekenmerk deur weinig differensiasie. Oxystele variegata was 'n uitsondering en het 'n ontwrigting van laat Pleistoceen oorsprong getoon tussen individue langs die weskus Namaqua Biostreek en dié in die suid kus Agulhas biostreek. Hierdie resultate voorsien sterk bewyse van die belangrike rol wat die Pleistoseen klimaatsveranderinge gespeel het in die vorming en verspreiding van biodiversiteit langs die Suid-Afrikaanse kus. Daarbenewens, geen vloei in alle spesies, behalwe O. tigrina, was merkwaardig asimmetries. Kaap Infanta en Port Elizabeth verteenwoordig moontlik die bron bevolkings. Met inagneming van die geringe bevolking genetiese struktuur en geenvloei patrone wat waargeneem is vir die meeste slak spesies wat bestudeer is, word dit aanbeveel dat T. sarmaticus, O. sinensis, O. tigrina en B. rhodostoma bestuur word as 'n panmiktiese bevolking, en dat die streek wat Kaap Infanta en Port Elizabeth insluit geprioritiseer moet word vir bewaring. Oxystele variegata was die enigste spesie wat duidelike bevolking struktuur getoon het en in hierdie geval, moet spesie spesifieke bewaringspogings aangewend word.
603

To Fee or Not to Fee: Building Student Support for Additional Library Revenue

Cuillier, Cheryl, Huff-Eibl, Robyn, Brewer, Michael 24 April 2012 (has links)
Poster presentation from the Living the Future 8 Conference, April 23-24, 2012, University of Arizona Libraries, Tucson, AZ. / The University of Arizona has had a student library fee since 2006. The fee started out at $15/year for students and now stands at $120/year. In FY2011-12, fee revenue for the University Libraries is expected to be about $3.5 million—a critical chunk of our budget. This poster will describe the approach that enabled the Libraries to successfully implement a fee. Garnering support from student government leaders and advisory boards has been crucial. The poster will also detail how student fee money is used, challenges we’ve faced, and strategies that might work at your institution.
604

Following the TRAIL: Gift-Cultures and Collaborative Efforts for the Library Community

Oxnam, Maliaca, Waltz, Marie, Blake, Joni 02 May 2008 (has links)
Breakout session from the Living the Future 7 Conference, April 30-May 3, 2008, University of Arizona Libraries, Tucson, AZ. / This session will examine the development of the Technical Report Archive & Image Library (TRAIL) and its current meta-community. Participants in the Greater Western Library Alliance's (GWLA) TRAIL project have developed a model for complex collaborations that includes both 1) shared management for physical collections; and 2) shared large-scale digital conversion processes. The model supports achieving a shared vision, regardless of the number of participants, geographic location, collection scope, or member assets and is accomplished through the recognition and use of learning organization techniques, social capital and gift-culture principles. The session will cover the structure that has been developed to address geographic barriers and workflow issues for this massive digitizing project. Discussion will also include how the structure offers institutions a flexible, short-term way to participate in a digitizing project, without breaking the bank or investing in additional computer systems. Audience participation and feedback on the model will be encouraged.
605

Tick Tock, Tick Tock - Shortening the Strategic Planning Clock: Strategic Planning at the University of Arizona Library

Oxnam, Maliaca, Martin, Jim, Ammon, Mona, Knowlton, Sharon, Ray, Michael 06 April 2006 (has links)
Conference proceeding from the Living the Future 6 Conference, April 5-8, 2006, University of Arizona Libraries, Tucson, AZ. / The UA Library embarked on a new long-range strategic planning process utilizing new techniques to determine our future directions. Come hear how we shortened our planning process and where we’re headed in the future!
606

The Relative Value Scale: How Relevant Is a Journal to Your Institution’s Research & Instruction?

Dewland, Jason C. 24 April 2012 (has links)
Poster presentation from the Living the Future 8 Conference, April 23-24, 2012, University of Arizona Libraries, Tucson, AZ. / Due to significant cuts in the University of Mississippi's library budget, a ranking system was needed to determine the value of a journal to the local research and instruction needs. Major journal rankings products are not a strong resource to measure a journal's value because they exclude many journals and do not account for local research preferences. What was created was a simple algorithm to rank the business journal collection based on varying levels of usage, citations, and pricing. This poster will present an explanation of the algorithm, the resulting rank-order list, and what journals were actually cut.
607

Some beach changes at selected bays in Hong Kong

Williams, Allan Thomas. January 1972 (has links)
published_or_final_version / Geography and Geology / Doctoral / Doctor of Philosophy
608

Global climate change: environmental implications for Hong Kong

Leung, Wai-hung, 梁偉鴻 January 1996 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
609

A management strategy for potential human population movements as a result of climate change

McLeman, Robert Andrew. January 1995 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
610

Climatic change and Chinese population growth dynamics over the last millennium

Lee, Fung, 李峰 January 2007 (has links)
published_or_final_version / abstract / Geography / Doctoral / Doctor of Philosophy

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