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Dissertations / Theses on the topic 'Portion'

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Published: 4 June 2021
Last updated: 30 July 2024

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1

Edens, Kim Louise. "Grain-based foods 24-hour portion size recall compared to photo portion selection by university students." Online version, 2003. http://www.uwstout.edu/lib/thesis/2003/2003edensk.pdf.

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2

Weber, Judith Lynne. "Effects of training on portion size estimation." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186506.

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The effectiveness of training individuals in portion size estimation skills in order to increase their accuracy of food quantity estimation was investigated. The retention of gain in estimation accuracy over six months and the effects of the completion of diet records on the retention of estimation accuracy were also investigated. A multi-technique training program combining the measurement and estimation of real foods and food models by standard household measurements and dimensions was used. Three foodforms were represented: solids, liquids, and amorphous foods. Two subject samples, composed of Caucasian females, 28-42 years old, were recruited. One sample (n = 25) was pretested on portion size estimation accuracy, trained, and posttested. They subsequently completed four randomly assigned, nonconsecutive days of diet records and were posttested again six months after their first posttest. The other sample (n = 66) was randomly assigned to one of four groups using the Solomon four-group design: (1) control, pre- and posttested, (2) control, posttested only, (3) trained, pre- and posttested, and (4) trained, posttested only. One control group (Group 2, n = 14) and one trained group (Group 4, n = 14) were administered a second posttest six months after their first posttest for comparison with the other subject sample. Groups 2 and 4 did not complete diet records during the six month period between posttests. Using 14 separate 2 x 2 ANOVAs, results showed that training significantly increased portion size estimation accuracy calculated by difference ("D" method, p =.007) and by absolute value ("Ab" method, p =.003). This training effect for the total test was attributed specifically to the increase in estimation accuracy for solids estimated in cups ("D" method, p =.000; "Ab" method, p =.008) and for amorphous foods ("D" method, p =.000; "Ab" method, p =.000). Comparisons between first and second posttest scores for Groups 2, 4, and the group that completed diet records were analyzed using paired t-tests and mixed model ANOVAs. Post hoc tests included Tukey's HSD test and orthogonal contrasts (p≤.05). Both trained groups retained their gain in estimation accuracy over six months for all but one variable, and the completion of diet records improved estimation of solid foods by dimensions.
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3

Badham, Neil Francis. "Synthetic studies towards the spiroketal portion of avermectins." Thesis, University of Reading, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357197.

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4

Beeslaar, Salome. "Geomorphology of a portion of Mariepskop, South Africa." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/40238.

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Hillslopes usually have high heterogeneity in terms of landscape processes. Interactions occur between geology, geomorphological processes, and vegetation distribution on a hillslope. This study was undertaken to assess the processes and interactions of geology, regolith production, geomorphological processes, channel formation and how these are influenced by the vegetation on a portion of Mariepskop. Mariepskop forms part of the Drakensberg Escarpment, but is a separate hillslope within the Mpumalanga Province. A north-eastern portion of the Mariepskop forms the study site, with a drainage line located within the site. Deciduous bush covers most of the study site, and grassland patches occur on the southern parts of the study site. Quartz-feldspar-biotite gneiss dominates most of the area with the cliff and higher parts consisting of feldspar-rich schist. Three site visits were undertaken where bedrock geology, weathering, soil formation, erosion, mass movement processes and the drainage channel were assessed. Maps of these processes as well as slope profiling and plan forms were compiled. According to the results, Mariepskop shows heterogeneous processes both laterally and vertically, with various degrees of interactions taking place. Underlying geology, mass movements on higher altitudes, and soil creep on lower altitudes occur on both the northern and southern parts. Processes mainly occurring on the northern part are rockfall from drainage channel incision, weathering, rill erosion and fluvial erosion within the drainage channel. Main processes on the southern part are mass movement in term form of slumping/debris flow, and erosion, in particular rainsplash and overland flow. Soil is deeper on northern part than on southern part of the study site. Geomorphological processes interact with the vegetation distribution over the study area. Grassland patches on the southern part of the study site are mainly due to slumping/debris flow, rainsplash erosion, convexity of the plan form (therefore no valleys) and oxidic soils occurrence. Similar geomorphological processes will probably influence grassland patches over the rest of Mariepskop.
Dissertation (MSc)--University of Pretoria, 2013.
gm2014
Geography, Geoinformatics and Meteorology
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5

Dixon, Brian L. "Portion Size Selection in Relation to Hemoglobin A1Cs." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/honors/219.

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Obesity has been recognized as an increasing issue within our country. Obesity contributes to many health related issues, including type 2 diabetes mellitus. Portion size is a factor that has generated clinical research interest. The aim of this study was to determine if there was a relationship between management of diabetes measured by hemoglobin A1c and portion size selection for type 2 diabetics. In this study, subjects selected portion sizes of four different foods. Data were compared to recent A1c levels. Due to the small sample size, nonparametric statistical analysis was used. The relationship of grain portion weight selection and A1c was significant (Spearman R = .900, p = .037). This finding has potential for future investigation and patient education.
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6

Ashkanani, Fatemah. "Portion sizes and dietary assessment methods for South Asian children." Thesis, University of Leeds, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.659024.

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The South Asian population is the largest minority ethnic . group in the UK. Their diet and food habits depend on their geographical origin, but they can change after migration due to acculturation. It has been observed that South Asians have a higher risk of diet related diseases than white Caucasians. Another observation is that diet during childhood affects health outcomes in adulthood. The main aim of this thesis is to develop and validate dietary assessment methods adapted to South Asian children aged 4-11 years living in the UK and to test the hypothesis that their diets and food habits are influenced by both their original and adopted cultures. Food portion photographs were developed and tested. Following this, detailed dietary information was collected from mothers of South Asian children aged 4-11 years through completion of a food habit questionnaire (n=190) and three multiple pass 24-hour recalls (n=150, total 450 interviews). A verage portion sizes of commonly consumed foods were calculated. The results showed that South Asian Food Portion Photographic Atlas can be used to improve the accuracy of portion estimation of South Asian mothers. South Asian children tended to consume mainstream foods as part of their breakfast, snacks and lunch, while more traditional foods were eaten as part of their afternoon snack and dinner. Some significant differences were found in median portion sizes by ethnicity, religion, gender and age group. The energy intake was close to the UK's EAR, whereas most of the vitamins and minerals obtained exceeded the UK's RNIs. Furthermore, they had a significantly lower intake of vitamin D when compared with WHO recommendations. It is recommended that longitudinal studies are undertaken in order to establish ethnic-specific requirements for this group.
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7

Lewis, Hannah Bethan. "Food portion size and implications for appetite control and obesity." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648597.

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8

Spence, Charles F. "Nanobiology : halting steps into a portion of Richard Feynman's vision." Diss., Pasadena, Calif. : California Institute of Technology, 2002. http://resolver.caltech.edu/CaltechETD:etd-10082002-182045.

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9

Reader, Michael. "Studies towards the synthesis of the macrolide portion of ulapualide A." Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294255.

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10

Bi, Feng Jr. "The Asymmetric Synthesis Of The C1'-C10' Portion of Pamamycin-621A." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36903.

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This thesis describes the synthesis of the C1'-C10' portion 72 of the pamamycin-621A using a cuprate conjugate addition to join enone fragment 52 and organostannane fragment 64a. Fragments 52 and 64a were both synthesized from (S)-methylketene dimer 51.
Master of Science
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11

Vogel, Alexandre. "Modélisation du champ des vitesses dans le bolus urinaire dans une portion cylindrique de l'uretère humain : étude dynamique dans la paroi dans un coude (portion de tore)." Paris 6, 2006. http://www.theses.fr/2006PA066588.

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12

TERNEL, CHEVAL VALERIE. "Les carcinomes epidermoides de la langue mobile et du sillon pelvi-lingual : experience du centre oscar lambret de 1974 a 1983 : 744 cas." Lille 2, 1989. http://www.theses.fr/1989LIL2M290.

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13

Movin, Tomas. "Aspects of aetiology, pathoanatomy and diagnostic methods in chronic mid-portion achillodynia /." Stockholm, 1998. http://diss.kib.ki.se/1998/91-628-2817-7.

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14

Vrba, Susanne G. "The Writing Portion of the TASP Test: Does Instruction Make a Difference?" Thesis, University of North Texas, 1992. https://digital.library.unt.edu/ark:/67531/metadc501265/.

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This investigation sought to determine the effects of composition instruction on student performance. Informants consisted of students and teachers. Students completed two surveys and participated in interviews. Teachers completed one survey. The findings suggest that student performance are influenced by confidence in writing ability and previous writing instruction. Further, teachers either teach composition actively or inactively, and these teacher stances influence both student confidence and ability to compose. Implications from these findings can be extended to teacher training, student instruction, and further research.
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15

Smith, Tracy René. "The effectiveness of video training on accuracy of food portion size estimation /." The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486462702465892.

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16

Lever, Katie. "Portion Control: An Examination of Organizational Control and Male Athlete Eating Disorders." TopSCHOLAR®, 2018. https://digitalcommons.wku.edu/theses/2575.

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Eating disorders (EDs) are strikingly common among American adults. Past research has indicated that athletes in general are particularly vulnerable to developing EDs due to media pressure, athletic drive, and the population’s proclivity to perfectionism. Most ED research, both in athletic and non-athletic populations, is female-focused, as women are more likely to develop EDs. However, men are still susceptible to develop EDs and are understudied. Links between lack of autonomy and EDs exist in familial settings, but have yet to be applied in organizational settings. This quantitative thesis sought to bridge a research gap by assessing ED levels in male NCAA Division 1 athletes and examining the relationships with perceived levels of concertive, institutional, and simple control present in athletic settings. Findings indicated that although athletes perceived different forms of control in their sport, these forms of control did not negatively affect their eating habits. Implications and direction for future research are explored.
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17

OLIVATTO, GLAUCIA PEREGRINA. "STUDY ABOUT MICROPLASTICS IN SURFACE WATERS IN THE WESTERN PORTION OF GUANABARA BAY." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2017. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=29926@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
AGÊNCIA NACIONAL DE PETRÓLEO
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
Partículas de plásticos com tamanho inferior a 5 milímetros, denominadas microplásticos, estão entre os contaminantes que ameaçam o ambiente marinho. A presença de microplásticos em suspensão na coluna d água é motivo de grande preocupação, devido à sua ampla distribuição, capacidade de adsorção e dispersão de contaminantes orgânicos e potencial de ingestão por organismos na base da cadeia trófica. Nesse contexto, o objetivo central deste estudo foi avaliar a ocorrência desses resíduos nas águas superficiais na porção oeste da Baía de Guanabara, através da determinação de sua composição qualitativa e quantitativa. Amostras de microplásticos foram coletadas em três campanhas no verão de 2016, através do arrasto horizontal com rede de 330 micrômetros em três diferentes áreas potencialmente afetadas por plásticos. As partículas menores que 5 milímetros foram isoladas por peneiramento via úmida, triadas com o auxílio de uma lupa binocular e classificadas de acordo com a sua forma, cor e tamanho. A quantidade de microplásticos foi determinada por gravimetria, contagem manual e processamento digital de imagens, obtidas por microscopia óptica. O tipo de polímero em cada categoria foi determinado por espectroscopia de absorção no infravermelho médio (FT-IR) com refletância total atenuada (ATR). Os resultados obtidos, considerando-se as três campanhas, indicam que os polímeros mais representativos foram polietileno e polipropileno correspondendo, respectivamente, a 71,5 mais ou menos 8,1 por cento e 23,8 mais ou menos 5,8 por cento do total analisado. Partículas inferiores a 1 milímetro foram as mais abundantes com média de 34,0 mais ou menos 9,6 por cento. Os plásticos classificados como fragmentos e filmes foram os mais encontrados representando, respectivamente, os valores médios de 44,3 mais ou menos 9,3 por cento e 33,7 mais ou menos 10,1 por cento. Microplásticos coloridos foram os predominantes, apresentando valores acima de 40,0 por cento. Os resultados obtidos comprovam a ocorrência de microplásticos nas águas superficiais da Baía de Guanabara, indicando que a falta de manejo de resíduos sólidos em sua bacia de drenagem contribui com esse panorama, sendo esse, portanto mais um problema ambiental a ser investigado.
Plastics particles smaller than 5 millimeter, known collectively as microplastics, are among the hazardous contaminants that threaten the marine environment. Microplastics suspended in the water column are of concern because of its widespread distribution and potential to carry on adsorbed contaminants in a global scale as well the and potential ingestion by organisms at the base of the trophic chain. In this context, the main objective of this study was to evaluate the occurrence of such wastes on surface waters of the western portion of Guanabara Bay, by determining their qualitative and quantitative composition. Microplastics samples were collected in three campaigns in the summer of 2016, through horizontal drag with 330 micrometers net in three different areas potentially affected by plastics. Particles smaller than 5 millimeter were isolated by wet sieving, screened with the aid of an ocular magnifier and classified according to their shape, color and size. The amount of microplastics was determined by gravimetry, manual counting and digital images processing, obtained by light microscopy. The type of polymer in each category was determined by absorption spectroscopy of mid infrared (FT-IR) with attenuated total reflectance (ATR). The results obtained, considering the three campaigns, indicate that the most representative polymers were polyethylene and polypropylene corresponding, respectively, to the mean values of 71.5 more or less 8.1 per cent and 23.8 more or less 5.8 per cent. Particles smaller than 1 mm were the most abundant indicating the mean of 34.0 more or less 9.6 per cent. Plastics classified as fragments and films were the most found representing, respectively, the mean values of 44.3 more or less 9.3 per cent e 33.7 more or less 10.1 per cent. Colored microplastics were the predominant, ones presenting values above 40.0 per cent. The results obtained confirm the occurrence of microplastics in the surface waters of Guanabara Bay, indicating that the lack of solid waste management in its drainage basin contributes to this scenario, which is therefore an environmental problem to be investigated.
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18

Ammon, Leigh Auwers. "Trends in Water Quality within the Broward County Portion of the Biscayne Aquifer." FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/868.

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Continuous and reliable monitoring of contaminants in drinking water, which adversely affect human health, is the main goal of the Broward County Well Field Protection Program. In this study the individual monitoring station locations were used in a yearly and quarterly spatiotemporal Ordinary Kriging interpolation to create a raster network of contaminant detections. In the final analysis, the raster spatiotemporal nitrate concentration trends were overlaid with a pollution vulnerability index to determine if the concentrations are influenced by a set of independent variables. The pollution vulnerability factors are depth to water, recharge, aquifer media, soil, impact to vadose zone, and conductivity. The creation of the nitrate raster dataset had an average RMS Standardized error close to 1 at 0.98. The greatest frequency of detections and the highest concentrations are found in the months of April, May, June, July, August, and September. An average of 76.4% of the nitrate intersected with cells of the pollution vulnerability index over 100.
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19

Abrahams, Gharlied. "The geotectonic evolution of a portion of the Garies terrane, Kliprand, South Africa." University of the Western Cape, 2016. http://hdl.handle.net/11394/6227.

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Magister Scientiae - MSc (Earth Science)
The Kliprand dome is a poorly investigated structure located in the central part of the high grade Garies Terrane of the western Namaqua Sector (NS) of the Namaqua-Natal Metamorphic Province (NNMP). This structure is host to a diverse variety of supracrustal rocks comprising predominantly metapelites and quartzites of the Kamiesberg Group, the streaky augen gneiss, an enigmatic pink gneiss (official name the Lekkerdrink Gneiss) of which the origin is obscure, the metasomatic charnockites along with the pre- to syn-tectonic two-pyroxene granulites (or gabbro-norite) of the Oorkraal Suite. Large bodies of garnet-quartz-feldspar granite, believed to be the products of dehydration melting during peak metamorphism, are referred to as the Ibequas Granite. The transformation of these sediments and volcanic rocks into gneisses and migmatitites was accomplished by intense regional metamorphism during the 1.2-1.0 Ga Namaqua Orogeny. In order to unravel the tectonic evolution of the Kliprand dome, a structural, lithogeochemical, isotopic and geochronological study was undertaken.
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20

Antoine, Tatiana. "Biosynthèse de la portion oligosaccharidique de différents glycosphingolipides par ingénierie métabolique d'Escherichia coli." Université Joseph Fourier (Grenoble), 2004. http://www.theses.fr/2004GRE10094.

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Les motifs oligosaccharidiques des glycosphingolipides sont impliqués dans des phénomènes de reconnaissance cellulaire et de transduction du signal ainsi que dans diverses pathologies. Ils ne sont pas disponibles en grande quantité, car leur synthèse chimique est difficile. Une nouvelle méthode, "l'usine cellulaire", développée au laboratoire a permis de produire des oligosaccharides dérivés du lactose à faible coût par culture à haute densité cellulaire des souches d'Escherichia coli qui surexpriment des glycosyltransférases et des glycosyl-nucléotides synthétases. Dans ce travail, les portions oligosaccharidiques de différents gangliosides (GM2, GM1, GA2, GA1 et GD3) et globosides (Gb3-Cer, Gb4-Cer) ont été synthétisées à grande échelle (à l'échelle du g. L-1), purifiées par chromatographie et caratérisées par spectrométrie de masse et RMN. Le motif oligosaccharidique facilement activable du GM3 (sialyllactose b-allylé) a été obtenu en utilisant de l'allyl b-lactoside comme précurseur
Glycosphingolipids oligosaccharides are involved in a number of events in adhesion/recognition and signal transduction and in some pathologies. They are not readely available, due to the difficulty of chemical synthesis. A new process, the "cell factory" has been recently developped in our laboratory for the low cost production of lactose derived oligosaccharides by living recombinant Escherichia coli overexpressing the suitable sugar-nucleotides synthases and glycosyltransferases genes. In this work, the carbohydrate moieties of several gangliosides (GM2, GM1, GA2, GA1 and GD3) and globosides (Gb3-Cer, Gb4-Cer) have been efficiently produced (at the g. L-1 scale), purified by chromatography and caracterized by mass spectrometry and NMR. The readily activable oligosaccharide moiety of GM3 (b-allyl sialyllactose) has been obtained using allyl- b-lactoside as precursor
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21

Hight, Krista. "Food portion size perceptions of various athletes at the University of Wisconsin-Stout." Online version, 2008. http://www.uwstout.edu/lib/thesis/2008/2008hightk.pdf.

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22

Stambaugh, Michael C. Guyette Richard P. "Fire risk assessment of the western portion of the central hardwoods forest region." Diss., Columbia, Mo. : University of Missouri--Columbia, 2008. http://hdl.handle.net/10355/6628.

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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 25, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Richard P. Guyette. Vita. Includes bibliographical references.
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23

McGaughy, Joseph Taylor Swingen Abigail Leslie. ""A louse for a portion" early-eighteenth-century English attitudes towards Scots, 1688-1725 /." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/History/Thesis/Mcgaughy_Joseph_30.pdf.

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24

Yousef, Diana O. "Structural and functional characterization of the lumenal portion of putative cargo receptor, yp24A/Emp24p /." Access full-text from WCMC:, 2007. http://proquest.umi.com/pqdweb?did=1296098021&sid=3&Fmt=2&clientId=8424&RQT=309&VName=PQD.

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25

Kelly, Mary T. "Investigation of the contribution made by food portion size to food and energy intake." Thesis, University of Ulster, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529539.

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26

Leinbach, Alan Edward. "A geochemical study of a layered portion of the Horoman peridotite, Southern Hokkaido, Japan." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/54323.

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27

Roby, Philippe. "Étude de la portion C-terminale du Melanoma Growth Stimulating Activity (MGSA/gro[alpha])." Doctoral thesis, Université Laval, 1996. http://hdl.handle.net/20.500.11794/50246.

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28

Bennett, Rebecca A. "The Sediment Transport and Capacity in the Channelized Portion of Hocking River, Athens, Ohio." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1338491127.

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29

White, Joshua A. "Geomorphic analysis of stream crossings in a portion of the Upper Cheat River basin." Morgantown, W. Va. : [West Virginia University Libraries], 2004. https://etd.wvu.edu/etd/controller.jsp?moduleName=documentdata&jsp%5FetdId=3688.

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Thesis (M.S.)--West Virginia University, 2004.
Title from document title page. Document formatted into pages; contains x, 71, [49] p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 68-71).
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30

Pollock, J. Michael. "Geology and geochemistry of hydrothermal alteration, eastern portion of the North Santiam mining area." PDXScholar, 1985. https://pdxscholar.library.pdx.edu/open_access_etds/3582.

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The Ruth Mine is a base-metal vein deposit near the eastern margin of a reported porphyry copper deposit in the Western Cascade Range in Oregon. Uplift of the Western Cascade Range has resulted in a deeply dissected terrain in which more than a kilometer of the stratigraphy overlying the porphyry-style mineralization is preserved and exposed. The stratigraphic units, which are middle Tertiary in age, have been given arbitrary letter designations beginning with the lowest unit (Unit A) through the uppermost unit (Unit D).
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31

Robson, Paula Jayne. "The development and evaluation of food photographs as a tool for quantifying food intake in dietary surveys." Thesis, University of Ulster, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241996.

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32

Trafford, Claire de. "The contract of marriage : the maritagium from the eleventh to the thirteenth century." Thesis, University of Leeds, 1999. http://etheses.whiterose.ac.uk/2325/.

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The maritagium, or marriage portion, was the gift of land or rents given by a father on the occasion of his daughter's marriage. Using the evidence of the surviving charters, printed and archival, which detail the terms and conditions of this grant, in combination with those charters made by the donees or their heirs which refer to the maritagium, and other evidence such as law suits and administrative records (again printed and manuscript), my thesis examined the actual grant and enjoyment of the maritagium in England. It will be shown that the custom of the maritagium was widespread, if not universal, and penetrated all ranks of society. Furthermore maritagia seem to have been given to more than one daughter, and even, on occasion to illegitimate daughters, when the family could afford to do so. This indicates that medieval society, in this period, did not concentrate its resources in the hands of one heir but distributed land within the family, in contrast to previous work which has emphasised the growing concentration of land in the hands of the male heir. The mechanism and method of granting the portion remained remarkably similar over time, varying only in the amount of land, or rent, given as a portion. In particular the thesis examines the maritagium in relation to the lives of women; the charter and legal evidence had strongly indicated that the maritagium was accounted part of the lands of a woman. Examining the maritagia charters it was evident that the charter language changed over the period to reflect this fact, changing from a gift made from a man to a man with a woman, to a gift made to a couple. This change occurred over the course of the twelfth century but, regardless of who the donee was in the original charter, or what the language used seemed to signify, from the earliest period widows were found in control of their maritagium lands. This fact had important ramifications for the position of women within society; for those women who were not heiresses marriage gave a claim to lands which they could utilise in their widowhoods. Furthermore, and unlike dower, the maritagium resembled inherited land in that it could be permanently alienated by a widow if she so desired. These findings were reinforced by the customs to be found written in the works attributed to Glanvill and Bracton, and by the surviving law suits recorded at the eyres of medieval England. In these cases the rights of women to their maritagia were asserted by widows and reinforced by the courts. In this period the ability to own and alienate land conferred power, and the maritagium gave many women the right to lands and powers which they would otherwise have lacked. This was the case until the enactment of the statute De Donis in 1285 which barred both men and women from alienating the maritagium away from their heirs, or from preventing the reversion to the donor's heirs should they prove childless. This statute, which forms the upper date limit of my thesis, thus had a major impact on the rights of women over their property, and also on the customary arrangements made by families with regard to their lands. The maritagium was not, however, only of relevance to women. It did form an important part of the lands of women who were not heiresses, indeed the practice was linked to female inheritance customs, but during marriage the maritagium was controlled and utilised by the husband. In this way men also participated in the gift. In addition because the maritagium involved the passing of land from one family to another the maritagium enabled marriage to be used as a means of dispute settlement or alliance, political, social or economic. By making prudent marriages a family could also accumulate land near the centre of the patrimony whilst disposing of outlying land as maritagia in turn. The maritagium gift thus played a major role in medieval society.
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33

Bath, Octavia. "Provenance of Siliclastic Sedimentary Rocks in the Eastern Portion of the North Caribou Greenstone Belt." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36115.

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The Zeemal Heaton Lake metasedimentary assemblage comprises ~50% of the eastern limb of the North Caribou greenstone belt, which hosts the Musselwhite gold deposit (~ 5.4 Moz Au). The metasedimentary assemblage is divided into two based on their distribution: the Central-belt and North-rim of the belt. The Zeemal Heaton Lake metasedimentary rocks have been interpreted to represent a turbidite succession, consisting of pelite, arkose, wacke and conglomerate. Detrital U-Pb zircon age populations from this study indicate variable sources in the Central-belt metasediments with a maximum age of deposition of 2798.8 ± 29 Ma, while metasediments along the North portion of the limb display a maximum age of deposition of 2696 ± 39 Ma. This indicates the likelihood of two discrete basins with the Zeemal Heaton Lake assemblage. Neodymium isotopic values for the sedimentary rocks along the North-rim of the belt display εNd2680Ma ranging from -1.2 to -0.9. An overlapping but slightly more evolved signature shown in the Central portion with values of εNd2800Ma -1.6 to 0.1. This indicates detritus for the Central-belt was likely sourced from the older (~2850 Ma), (tonalite-granodiorite) surrounding intrusions. The North-rim sediments were sourced (in part) from the younger (~2700 Ma) granitic intrusions and rhyolites. The surrounding batholiths display εNdt overlapping with North-rim sedimentary rocks, however, indicate significant contribution beyond these immediate surrounding batholiths, which may include older mafic (2982 ± 0.8, 2870 ±2 Ma), younger rhyolitic unit (2723 ± 2 Ma) or more distal sources than the intrusions immediately adjacent to the belt. Peak metamorphic mineral assemblages indicate a minimum of amphibolite facies-garnet zone or greater across the Central-belt portion of the greenstone belt. The North-rim metasediments display evidence for aureole metamorphism which may overprint earlier regional metamorphism. Nitrogen abundance and δ15N values of biotite of the Zeemal Heaton Lake metasedimentary assemblage indicate variable values than those associated with mineralization at the Musselwhite Mine, which is reported by Isaacs (2008). Mineralizing fluids from the Musselwhite mine have been interpreted by Issacs (2008) to be related to both metamorphic and magmatic fluids. Fluids associated with the Eyapamikama and/or Zeemal Heaton Lake metasediments appear to be metamorphic with minor magmatic influence near regional shear zones, but not directly related to the auriferous fluids which formed the Musselwhite mine.
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34

Ford, Andrew J. H. "Tectonic influence on permian sedimentation, central portion, Pepita-Wackett-Nockatunga Trend, Cooper Basin, Southwest Queensland /." Title page, contents and abstract only, 1986. http://web4.library.adelaide.edu.au/theses/09S.B/09s.bf699.pdf.

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35

Faulkner, Gemma. "Food choice and energy intake: the impact of portion size, energy density and food cost." Thesis, Ulster University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.669659.

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Understanding the complex linkage between obesity and food choice is pivotal to establishing effective dietary guidance that resonates with consumers. The aims of this thesis were to evaluate: (1) serving size (SS) guidance schemes and their effectiveness; (2) consumer estimations of portion size (PS) and energy density (ED), and anticipated consumption guilt (ACG) for perceived 'healthier' vs. 'standard' foods; (3) consumer opinions, perceptions of efficacy and the precision of a range of portion size estimation aids (PSEA); and (4) the nutritional quality (NQ) and energy cost (EC) of own brand (OB) vs. market brand (MB) foods. A literature review and three studies were undertaken. In the first study, three pairs of isoenergy dense (kJIlOOg) foods - 'healthier' vs. 'standard' cereals, drinks and coleslaws - were selected. For each food, subjects (n186) served an appropriate PS for themselves, estimated its ED and rated their ACG. Subjects estimated larger portions of the ' healthier' (reduced fat) coleslaw than the 'standard' version, and perceived all 'healthier' foods to be lower in ED than their 'standard' alternatives, despite being isoenergy dense. Higher ACG was associated with the 'standard' foods . In the second study, a range of PSEA were evaluated using both qualitative (six focus groups, each of three to eight participants) and quantitative (practical use of PSEA; n 120) methods. Consumers indicated preference for "visual" PSEA (reference objects, household measures e.g. cup, and indicators on food packaging) for amorphous cereal products such as rice. In the third study, a basket of commonly consumed foods (n 32) were compared in terms of NQ and EC at two time points using two methods of nutritional profiling. Despite OB foods being significantly lower in EC (£/MJ) than the MB, there were no differences in the overall NQ. In conclusion, consumer understanding of PS, perceptions of ED and preferences for PSEA should be considered in future dietary guidance. OB foods should be promoted as nutritionally comparable to their more expensive MB counterparts where appropriate.
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Thériault, Catherine. "Influence de la portion C-terminale de CA125 sur les caractéristiques associées à la tumorigénicité." Mémoire, Université de Sherbrooke, 2009. http://savoirs.usherbrooke.ca/handle/11143/4012.

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Le cancer de l'ovaire est le cancer gynécologique le plus létal. L'absence de symptômes aux stades précoces de la maladie serait en grande partie responsable de ce faible taux de survie. Comme pour tous les cancers, l'indépendance aux signaux de croissance, l'insensibilité aux signaux inhibiteurs de croissance, la résistance à l'apoptose, l'immortalisation des cellules, l'angiogénèse, l'invasion et la formation de métastase sont des facteurs qui peuvent favoriser la formation et la progression d'un cancer de l'ovaire. La majorité des cancers de l'ovaire exprimerait l'antigène tumoral CA125. On connait actuellement très peu de choses sur les fonctions et les rôles de cette protéine qui fait partie de la famille des mucines. Cependant, des études rapportées par d'autres groupes de recherche ont démontré que certaines mucines peuvent jouer des rôles importants dans le développement et la progression de différents cancers. Des résultats préalablement obtenus par notre laboratoire indiquent que l'expression de cette protéine favoriserait la tumorigénicité des cellules à différents niveaux. Afin d'approfondir nos connaissances sur les fonctions de CA125, des populations stables de cellules exprimant la portion carboxy terminale de la protéine ont été générées dans différentes cultures cellulaires. Les effets du domaine carboxy terminal de CA125 sur la transformation cellulaire, les caractéristiques associées à la tumorigénicité, les jonctions cellulaires et les différentes composantes du cytosquelette ont été analysés. Les résultats ont démontré que, chez la lignée cancéreuse de l'ovaire SKOV-3, le domaine carboxy terminal de CA125 favorise l'indépendance des cellules aux signaux de croissance, l'insensibilité aux signaux inhibiteurs de croissance et la résistance à différents agents génotoxiques utilisés en chimiothérapie. Des expériences effectuées chez les souris indiquent également que les effets du domaine carboxy terminal de CA125 chez les SKOV-3 augmentent grandement leur tumorigénicité. Ainsi, les résultats obtenus avec la lignée SKOV-3 semble [i.e. semblent] indiquer que CA125 pourrait agir comme un oncogène tel que démontré chez d'autres mucines. Les effets du domaine carboxy terminal de CA125 sur différentes cellules non-transformées immortalisées ou non ont ensuite été évalués. Globalement, les effets observés chez la lignée SKOV-3 n'ont pas été observés chez les cellules non-transformées analysées.Le domaine carboxy terminal de la protéine n'a pas non plus été en mesure de transformer les différentes cellules étudiées. Cependant, chez la majorité des populations exprimant le domaine carboxy terminal un allongement de la morphologie des cellules a été observé. Ce changement de morphologie semble indiquer que l'expression de la portion carboxy terminale de CA125 favorise l'induction d'une transition épithélio-mésenchymateuse. Pour conclure, bien que le domaine carboxy terminal semble favoriser fortement la tumorigénicité des cellules cancéreuses SKOV-3 aucun effet important n'a été remarqué chez les différentes cellules non-transformées analysées. Il est possible que cette absence de phénotype chez les cellules non-transformées découle du fait que les populations contrôles servant de base de comparaison auraient effectuées [i.e. effectué] une transition épithélio-mésenchymateuse en réponse aux conditions de culture cellulaire. Également, les effets du domaine carboxy terminal de CA125 seraient peut être [i.e. peut-être] dépendant [i.e. dépendants] de l'expression d'oncogènes supplémentaires exprimés chez les SKOV-3.
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37

Lawrence, Christine. "Etude des récepteurs pour la portion Fc des immunoglobulines G exprimés par les basophiles humains." Paris 5, 1993. http://www.theses.fr/1993PA05P075.

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38

Quenardel, Jean-Michel. "Géologie des Calédonides de Laponie occidentale (Norvège) : évolution géodynamique d'une portion d'orogène paléozoïque péri-atlantique." Paris 11, 1987. http://www.theses.fr/1987PA112485.

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L'étude géologique détaillée, basée sur une cartographie précise, des Calédonides de Laponie occidentale a permis la mise en évidence de huit d'unités tectoniques allochtones qui n'avaient pas été reconnues antérieurement. Une carte géologique au 1/100 000e accompagnée de nombreuses coupes détaillées et d'un schéma structural au 1/250 000e illustrent l'organisation de ce bâti orogénique. L'étude présente une reconstitution tectono-stratigraphique basée sur des analyses pétrographiques, géochimiques et géochronologiques. Il est ainsi confirmé l'existence de nappes allochtones de matériel précambrien (lames cratoniques) séparant les Externides des Internides à matériel paléozoïque. L'âge de mise en place majeure des nappes se situe au cours de la phase "scandinave principale", au Silurien supérieur. Les migmatites des Internides sont originales (phase potassique représentée par la muscovite et non par du feldspath), le facteur dominant de cette migmatisation est une fusion anatectique limitée (système quartz-plagioclase sodique-muscovite-vapeur associé à liquide-silicate d'alumine). L'étude des mylonites montre que la déformation intime des tissus cristallophylliens est précoce et indépendante de la mise en place des nappes mais qu'elle se produit au cours d'un même continuum de déformation. Par ailleurs, l'intensité du taux de déformation est indépendante de la distance aux plans de chevauchement. La généralisation de cette étude régionale a pu être effectuée par la réalisation de coupes systématiques au travers de l'orogène, sur près de 1 000 km. Il est ainsi présenté une synthèse originale des Calédonides scandinaves arctiques qui s'appuie sur un schéma structural au 1/ 1 000 000e où l'importance des lames cratoniques est soulignée. Cette ceinture arctique résulte, comme les domaines méridionaux, d'une évolution polycyclique reprenant du matériel précambrien déjà structuré. Sa place dans le domaine calédono-appalachien est discutée, sur les bases d'une reconstruction paléo­ géodynamique. On insiste enfin, à partir d'exemples concrets, sur la nécessité d'établir la géométrie des corps géologiques et la chronologie des événements avant d'en proposer des modèles d'évolution
Geological study, based on detailed mapping, of the Caledonides of Western Lapland shows the evidence of eight allochthonous tectonic units which have not been recognized before. A 1/100 000e geological map with numerous detailed crossed sections and a structural map at the scale of 1/250 000e show the geometry of the orogenic belt. A tectono-stratigraphical reconstitution, after petrographical, geochemical and geochronological studies, is proposed. It is confirmed the existence of Precambrian material allochthonous over thrusted nappes. Emplacement of thrusted nappes has occurred during the “main Scandinavian” orogenic phase. Migmatites (from middle internal units) are original rocks where K-phase is represented by muscovite instead of K-Feldspar). They result of a limited anatectic melting (quartz-Na-plagioclase-muscovite-vapor associate with liquid-Al silicate). Study of mylonites shows that, on the one hand, early small scale deformations of crystallophyllian rocks are independent of nappes emplacement but they are produced during th same continuum of deformation; on the other hand, the intensity of deformation rate is also independent of the distance to thrust planes. Generalization of the regional work has been done after study of systematic cross sections through northern part of the orogen (1000 km). It is proposed a synthesis of arctic Scandinavian Caledonides with a 1/1000000 structural scheme. The importance of the cratonic slabs (nappes of Precambrian material) is emphazised; the interpretation is quite different of what has been proposed up to now. This arctic part of the belt is the result, as southern part, of a polycyclic evolution reworking Precambrian material already deformed. His situation in the caledono-appalachian orogen is discussed on the base of a paleo-geodynamic framework. The necessity to build up the geometry of geological domains and the chronology of geological events before building evolution models is emphazised after examples
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39

Buisson, Claude. "De Cassis à Bandol, essai de géomorphologie littorale sur une portion du littoral méditerranéen français." Aix-Marseille 2, 1989. http://www.theses.fr/1989AIX23007.

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La transgression flandrienne a porté la mer à son niveau actuel. Ce niveau, en fonction des glaciations et des déglatiations a varié plusieurs fois pendant le quaternaire. Dans cette étude de morphologie littorale, nous avons essayé de faire un bilan de l'évolution d'une portion de littoral appartenant au domaine méditerranéen, et cela à partir de la transgression flandrienne. Pour arriver à établir ce bilan, il a été nécessaire de mettre en valeur les facteurs en présence relevant de la géologie, la tectonique, la climatologie, la biologie et la biochimie. Cette étude nous a mené à essayer d'évaluer les parts respectives des facteurs continentaux et des facteurs marins dans l'évolution de ce domaine littoral.
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40

Frey, Michel. "Luxation du tendon de la longue portion du biceps brachial : a propos de 11 observations." Université Louis Pasteur (Strasbourg) (1971-2008), 1990. http://www.theses.fr/1990STR1M059.

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41

Quenardel, Jean-Michel. "Géologie des Calédonides de Laponie Occidentale, Norvège évolution géodynamique d'une portion d'Orogène paléozoïque péri-atlantique /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37609054g.

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42

Kilama, John Jolly. "A new synthetic approach to the C-D ring portion of streptonigrin and its analogs." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184620.

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Two new synthetic methods for the construction of the C-D moiety of streptonigrin have been developed. The first is the cyclization of beta, gamma unsaturated ketals to cyanopyridines. These ketals were prepared from akylidenemalononitriles. The second method utilized is the ortho-directed metalation of benzamide or oxazoline derivative to give keto compounds. However, attempts to transform these keto compounds to akylidenemalononitriles by Knoevenagel condensations were unsuccessful. With the ease of the reaction and ready availability of starting materials, the beta, gamma unsaturated ketals offer versatile synthons for pyridine C ring synthesis.
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43

Pumayalli, Rene. "Watershed Modeling by Remote Sensing and AGWA - SWAT for Western Portion of Cusco Watershed - Peru." Thesis, The University of Arizona, 2008. http://hdl.handle.net/10150/193359.

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Erosion and flooding in the Cusco watershed have increased over the last 30 years due to urban growth and incorrect use of natural resources. New data for a section of the watershed were created with satellite image, spatial data, and geoprocessing software including Erdas Imagine 9.1 and ArcInfo and free information and software in the public domain on the internet. AGWA2.0 - SWAT modeling software used the data to assess the actual conditions of the study area (Model 1) including sediment yield, water yield, percolation, and stream flow. Then, two models were created by altering the conditions of the land cover/use grid: Model 2 changed the bare soil class into contour trenches, and Model 3 changed bare soil class into trees or forest. A comparison of Models 2 and 3 with the current state (Model 1) found that forestation, Model 3, would greatly decrease flooding and increase water infiltration.
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44

Knowles, Susan Anne. ""A certain portion of the whole." : inspectors, guardians and anatomists in East Anglia, 1832-1908." Thesis, Open University, 2009. http://oro.open.ac.uk/54210/.

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This thesis reassesses the workings of the Anatomy Act (1832) in East Anglia throughout the nineteenth century. Underpinning the practice of medical education was the need to acquire human corpses to permit the essential study of anatomy. Over the course of the century the source of anatomical material moved from bodies taken from their graves by bodysnatchers to unclaimed pauper corpses from workhouses and hospitals to the increasing use of the cadavers of lunatics from the vast Victorian asylums. The accepted view of the Anatomy Act is that it stopped bodysnatching but failed to ensure a plentiful supply of cadavers. Whilst recent research has largely focused on specific changes in Poor Law legislation or the impact of the reorganisation of medical curricula on the supply of corpses, this study widens the debate by identifying seven groups; bodysnatchers, teachers of anatomy, medical students, inspectors of anatomy, paupers, guardians and those who elected them to office and examines their respective parts in attempting to solve the perennial problem of the shortage of corpses for dissection. The shifting locus of power between the groups is examined with reference to external changes which were brought to bear on their relationships. Cambridge Medical School is used as a case study to highlight the difficulties provincial schools experienced in obtaining dissection material and to indicate how, in this particular case, they were solved by the actions of determined individuals resulting in Cambridge becoming one of the most successful medical schools in the country by the end of the nineteenth century. This research contributes to the small, but growing, number of regional studies which are necessary to enable us to gain an overview of the effect of the Anatomy Act on the study of medicine across Britain in the nineteenth century.
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45

Jarrett, Corey. "Analysis of an Exposed Portion of the Badwater Turtleback Shear-zone, Death Valley, California, USA." Thesis, University of Oregon, 2018. http://hdl.handle.net/1794/23181.

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The exposed shear zone within the footwall of the Badwater turtleback presents an excellent opportunity to explore the brittle-ductile transition. Within this shear zone, a variety of lithologies preserve the last stages of crystal-plastic deformation concurrent with exhumation of the turtleback. The included field study captures a snapshot of each lithologic element during the last stages of ductile deformation. The exposed shear zone's journey through the brittle-ductile transition is analyzed using the deformation mechanisms of calcite and quartz. A history of strain partitioning is constructed through comparison of the strain and temperature environments needed to facilitate each mechanism of crystal-plastic deformation. As the shear zone cooled, strain was partitioned from quartz-rich mylonitic gneiss to the calcite-dominated marbles and mylonites. Correlation of deformation temperatures with previous studies further constrains the timing of the last stage of ductile deformation to between 13 and 6 Ma.
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46

Maywood, Paul S. "Stratigraphic model of the southern portion of the Jim Bridger coal field, Sweetwater County, Wyoming." PDXScholar, 1987. https://pdxscholar.library.pdx.edu/open_access_etds/3719.

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Uppermost Lance and lowermost Fort Union Formation sediments are found in outcrop in the southern portion of the Jim Bridger coal field, located on the northeast flank of the Rock Springs Uplift in Sweetwater County, Wyoming. Twenty-nine surface sections and 581 subsurface (borehole) sections were evaluated and used to construct a stratigraphic model. Stratigraphic correlations with economically mineable coal seams in the Fort Union Formation north and south of the study area combined with definition of questionable local formational boundary locations are significant objectives in this investigation.
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47

Perez, Teran Isaac Antonio. "Stratal architecture and sedimentology of a portion of the Upper Cambrian Hickory Sandstone, central Texas, U.S.A." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1522.

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48

Bourdon, Lisa Marie. "An integrative approach to characterizing the estrogenicity gradient of a portion of the South Platte River." Thesis, University of Colorado at Denver, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10112628.

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Endocrine disrupting compounds (EDCs) from agricultural, industrial, and municipal sources can be found in many surface waters with potential adverse implications for human and ecosystem health. The South Platte River represents a significant source of water for the Denver Metro Area, yet little data exists concerning EDCs. The aim of this study is to evaluate the occurrence and effects of EDCs downstream from two major wastewater treatment plants (WWTPs). This study characterizes the estrogenicity gradient of the South Platte River in the Denver Metro area by combining data from qPCR analysis for liver vitellogenin (vtg) mRNA with liver NMR metabolomics after a 5 day in situ caged exposure of fathead minnows. Concurrent water samples collected from the start and end times of the exposures were used to determine the occurrence and concentration of wastewater contaminants. Results found 68 of 122 chemicals downstream of WWTP 1 and 73 downstream of WWTP 2, including known EDCs (e.g. nonylphenol and octylphenol). A steroidal estrogen, estrone, was only found downstream of WWTP 2. Consistent with the highest measured concentrations of wastewater estrogens, the highest levels of vtg mRNA were measured downstream of WWTP 2. Metabolomics data coincided with vtg data and showed little variation except downstream of WWTP 2, where male polar metabolomes showed increased levels of alanine and glutamate, which are utilized in VTG synthesis. PCA of male polar metabolomes showed significant separation of WWTP 2 from WWTP 1 and the reference site, further supported by PLS-DA scores plot. Female polar metabolomes showed significant separation between WWTP 1 and WWTP 2 using PLS-DA scores plot. This study demonstrates that qPCR and metabolomics data can be reliably and concurrently used to illuminate impacts from chemical exposures, although further research will better elucidate target genes and metabolites of interest.

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49

Moslehi, Farhood. "Simulation of the MAC Portion of IEEE 802.11 and Bursts of Errors for Wireless Data Networks." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36936.

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The focus of this research is to investigate the effects of bursts of errors and packet collisions on the performance of the medium access control (MAC) portion of the IEEE 802.11 wireless local area network (LAN) protocol.An important ingredient in rapid expansion of wireless networks is the seamless transition between wired and wireless systems. The IEEE standards group in charge of developing the widely used IEEE 802.3 LAN standard has developed the IEEE 802.11 wireless LAN standard. IEEE 802.11 remains hidden from the upper levels of the network, thus allowing a seamless transition between networks. The foundation protocol for the IEEE 802.11 standard, known as Distributed Foundation Wireless Medium Access Control (DFWMAC), operates at the MAC level of the Data Link Layer. The protocol bases its access control mechanism on a principle called Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA), which is an adaptation of the Carrier Sense Multiple Access with Collision Detection (CSMA/CD) protocol used by IEEE 802.3 standard. The collision avoidance scheme in CSMA/CA allows data packets to be transferred via the wireless medium with lower probability of packet collision. In a slotted multi-access wireless system, performance parameters are affected by the bit error rates on the communication channel. These errors occur as a result of noise introduced by the radio channel or data packet collisions. Collisions occur when two or more stations select the same time slot to transmit their data, thus causing corruption in data packets. In this research, a simulation model coded in Microsoft's Visual Basic programming environment is utilized to investigate the effects of bit errors and packet collisions on performance in CSMA/CA. Performance parameters used in this study include throughput, medium utilization, collisions and station data queue lengths. In the simulation model, error bursts in the communication channel are modeled using a simple Gilbert model with two states, good (G) and bad (B). State G is error free, thus errors can only occur while the model is in state B. Collisions are simulated by two or more stations starting to transmit data packets in the same time slot. Therefore, as the number of stations increases, more and more stations compete for the medium, resulting in an increase in the number of collisions. Collisions are also increased by the amount of traffic that each station introduces into the system. Station load is defined here as the number of data packets per unit time that are released by the higher network protocol layers.The results in Chapter 5 demonstrate that higher network throughput can be achieved when the aggregate load on the network is distributed. For example, 30 stations offering 20 kilobits per second (kbps) of load for a total of 600 kpbs, results in a network throughput of 585 kbps. However, three stations offering 200 kbps of load for a total of 600 kbps offered load, results in a network throughput of 486 kbps. The distributed load is serviced at a 17 percent higher rate. However, once the network becomes saturated at above 40 stations for this model, collisions will more than offset the performance gains produced by the distribution of load.Furthermore, reducing the packet size by 50 percent under an approximately 19.5 percent packet error rate results in a 12 percent gain in throughput. This is primarily due to higher utilization of the network by shorter packets. However, as the packet error rate is reduced, the performance gap between the two packet sizes is reduced. Once the errors are removed completely from the communications channel, the longer packets produce a higher throughput than the shorter packets.
Master of Science
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50

Richards, Ralph John. "A geological investigation of upper Transvaal sequence rocks in the northern portion of the Rooiberg fragment." Diss., University of Pretoria, 1987. http://hdl.handle.net/2263/61058.

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Abstract:
The stratigraphy , sedimentology and geochemistry of. the upper Transvaal Sequence rocks in the northern portion of the Rooiberg Fragment are researched. The Leeuwpoort Formation of the Pretoria Group was deposited in a fluvial palaeoenvironment. The basal arkosites in this unit reflect braided stream deposition, whereas the overlying shaly arkosi tes represent upward- fining cycles of point bar sedimentation. The uppermost main Leeuwpoort shale probably formed in a floodplain palaeoenvironment. The overlying Smelterskop Formation arenites indicate high energy flood conditions in a proximal fluvial palaeoenvironment. The extrusion of andesi tic lavas acted as an agent of change during the deposition of Smelterskop Formation sedimentary rocks. The upper and lower contacts of the Smelterskop Formation are disconformable and conformable, respectively. However, non-deposition of the main shale of the upper Leeuwpoort Formation and erosion by succeeding Smelterskop sedimentation in some areas, created local disconformities at the base of the Smelterskop Formation. The scattering of Si02 binary plots recorded in the geochemistry of the Rooiberg Group rhyolites indicates extensive alteration of these rocks. Petrogenetic conclusions drawn from the geochemistry must therefore be treated with caution. However, empirical data indicates two lava types, defined by major and trace element geochemistry and geographical position.
Dissertation (MSc)--University of Pretoria, 1987.
Geology
MSc
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