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Testing the influence of herding behaviour on the Johannesburg Securities ExchangeMunetsi, Raramai Patience January 2018 (has links)
Magister Commercii - MCom / Since the discovery of herding behaviour in financial markets in the 1990s, it has become an area of interest for many investors, practitioners and scholars. Herding behaviour occurs when investors and market participants trade in the same direction during the same time period, as a result of the influence of other investors. Studies on herding behaviour have been undertaken in both the developed and developing economies and majority of these studies have confirmed the existence of herding behaviour in the stock markets. Despite its tremendous growth, the South African financial markets are not immune to such market anomaly.
Herding behaviour on the JSE was first investigated in 2002 focusing in the unit trust industry on the South African stock market. Motivated by this, this study assessed the presence of herding behaviour using the Johannesburg Securities Exchange tradable sector indices. Four indices were employed, namely Financials, Industrials and Resources and were benchmarked against the JSE All Share Index for the period from January 2007 to December 2017. The industrials index ((FINI15) constitutes of 25 largest industrial stocks by market capitalization, the financials index (FINI15) comprises of 15 largest financial stocks by market capitalization, the resources index (RESI10) which represents 10 largest resources stocks by market capitalization and lastly the FTSE/JSE All Share Index defined as a market capitalization-weighted index which is made up of 150 JSE listed companies and is the largest index in terms of size and overall value JSE. The FTSE/JSE All Share Index was used as a benchmark for investors to check how volatile an investment is.
The South African economy experienced the effects of the 2008 global financial crisis from 01 July 2007 to 31 August 2009. This study split the examination period into three categories namely before the global financial crises which was the period starting from 1 January 2007 to 30 June 2007, then the period during the global financial crisis which was from 1 July 2007 to 31 August 2009 and lastly the period after the global financial crises which was from 1 September 2009 to 31 December 2017. Apart from the diversity of the indices, the length of the examination period also had a significant influence towards the magnitude of herding behaviour on the JSE.
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Alterações semelhantes à capacitação no sêmen bovino após a criopreservação utilizando diluidores a base de gema de ovo ou lecitina de soja / Capacitation-like changes in bovine semen after cryopreservation using extenders within egg yolk or soy lecithinZaffalon, Fabiane Gilli 11 December 2009 (has links)
O objetivo deste estudo foi avaliar os efeitos de três diluidores diferentes na criopreservação do sêmen bovino sobre a motilidade, hiperativação espermática, reação acrossomal, capacitação e peroxidação lipídica das membranas espermáticas. Foram realizadas seis colheitas de sêmen em intervalos quinzenais de dez touros zebuínos da raça Nelore. O sêmen in natura foi avaliado, dividido em três tratamentos: uma fração foi diluída em meio a base de gema de ovo (Botu-Bov® - diluidor 1), a segunda fração diluída em meio a base de lecitina de soja (Botu-Bov® - diluidor 2) e a terceira fração em meio AndroMed® (diluidor 3) também a base de lecitina de soja. Logo após as amostras foram submetidas à congelação. As avaliações do sêmen após descongelação consistiram na análise computadorizada das características de motilidade e nas análises pela citometria de fluxo quanto à reação acrossomal (PI/FITC-PSA/H33342); peroxidação lipídica (PI/C11-BODIPY581/591/H33342) e capacitação espermática através da estabilidade da membrana plasmática (Merocianina 540/Yo-Pro1/H33342). As variáveis foram submetidas à análise de variância e ao teste LSD para comparação das médias, ao nível de 5% de significância. O diluidor a base de gema de ovo preservou melhor a motilidade espermática, a população de células com integridade de membrana plasmática e acrossomo não reagido no sêmen bovino pós-descongelação que os diluidores a base de lecitina de soja. Os espermatozóides criopreservados com o diluidor a base de gema de ovo apresentou menor sub população de células hiperativas e com membrana plasmática desestabilizada quando comparados com os diluidores a base de lecitina de soja e o diluidor a base de gema de ovo possibilitou uma diminuição da peroxidação lipídica das membranas espermáticas / The objective of this experiment was evaluate the effects of three diferent extenders in bovine semen cryopreservation about motility, sperm hiperactivation, acrosome reaction, capacitation, and sperm membrane lipid peroxidation. It was made six collection of semen samples each 15 days of 10 Nelore bulls. Semen samples in natura was verify and divided in three treatments: The first one was extended in egg yolk base (Botu-Bov® Extender 1), second one was extended in soy lecithin base (Botu-Bov® Extender 2) and the third was extended in AndroMed® soy lecithin base too. After that, semen samples were submitted to freeze process. Semen evaluations after thawing were made with computer assisted sperm analysis (CASA) and flow citometry for acrosome reaction (PI/FITC-PSA/H33342), lipid peroxidation (PI/C11-BODIPY581/591/H33342) and sperm capacitation by plasma membrane stability (Merocianina 540/Yo-Pro1/H33342). Data obtained from experimental proceeding were submitted to variance analysis and LSD test to compare means with 5% of significance. Egg yolk base extender preserved better sperm motility, cell population with plasma membrane integrity and non-reacted acrosome in bovine semen after thawing than soy lecithin extenders. Cryopreserved sperm with egg yolk base extender displayed less subpopulation of hiperactivated cells, less destabilized plasma membrane and permitted a decrease of lipid peroxidation of membranes when it was compared with soy lecithin extender
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Os chifres entre a cruz e a espada : um estudo das festas de touros na Espanha nos séculos (XV-XVI)Ungari, Diego de Freitas January 2016 (has links)
Nessa pesquisa OS CHIFRES ENTRE A CRUZ E A ESPADA: um estudo das festas de touros (XV-XVI) na Espanha, buscamos identificar como se deu essa emergência de um discurso de controle régio e clerical sob as chamadas festas de touros nos séculos XV e XVI – sendo aquilo que chamamos de “os chifres entre a cruz e a espada” justamente essa leitura das festas taurinas que legitimaram e deram vasão a essa construção das festas mais austeras e em conformidade com as doutrinas e dogmas cristãos, naquilo que denominamos de discurso de ordenança festiva. Para isso, analisamos uma gama de documentos, entre uma Crônica (Crónica del Condestable de Castilla Don Lucas de Iranzo), um Tratado (Tratado do Jogo), Bula (Salute Gregis Dominici) e o prólogo de um Cancioneiro (Cancionero de Juan Alfonso de Baena) na tentativa de construir e identificar nessa tipologia diversa de documentos, as várias maneiras utilizadas para compor o discurso de ordenança festiva. Observáveis em três frentes de análise – o discurso clerical, o discurso clerical percebido e praticado ou não pela nobreza e o discurso espacial/heterotopológico (sendo esse último, de suma importância, e tendo sido analisado partindo do conceito foucaultiano de heterotopia e as várias possibilidades que ele pode representar na análise dos mais diversos espaços). Também, perseguimos ao longo da pesquisa um tema que apesar de já há muito debatido mostrou que ainda encontra terreno fértil para novos debates historiográficos, as festas em si – analisadas partindo da proposta da festa como questão e como discurso. / In this research HORNS BETWEEN THE CROSS AND THE SWORD : a study of the bulls parties (XV- XVI) in Spain, we seek to identify how was this emergence of a regal control speech and clerical specifically under the so-called bulls parties in the XV and XVI - being what we call " the horns between a rock and a hard place " just this reading of bullfighting festivals that legitimized and gave arterial runoff to that construction of the austere celebrations and they were in accordance with the Christian doctrines and dogmas , what We call the ordinance festive speech and gave way to this construction of more austere celebrations that were in accordance with the Christian doctrines and dogmas, in what we call the festive ordinance speech. In order to do so, we analyzed a range of documents, from a chronicle (Crónica del Condestable de Castilla Don Lucas Iranzo), a treaty (Tratado del Juego), a bula (Salute Gregis Dominici) and the prologue of a songbook (Cancionero de Juan Alfonso de Baena) in an attempt to identify and construct in this different typology the various ways used to compose the festive ordinance speech. Observable in three fronts of analysis - the clerical speech, the clerical speech perceived and practiced (or not) by the nobility and the space/heterotopological speech (the latter, of paramount importance, has been analyzed with Foucault's concept of heterotopia and the various possibilities that it can represent in the analysis of the most diverse spaces as a starting point). We also seek throughout the research a theme that, although it has been discussed many times before, still shows that there is fertile ground for new historiographical debates: the parties themselves – analyzed from the premises of parties as problem and as speech.
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Efeito da utilização de antioxidante no diluidor para a criopreservação de sêmen bovino avaliado através de testes complementares, inseminação artificial e fecundação in vitro /Borges, Juliana Corrêa. January 2008 (has links)
Resumo: Efeitos deletérios dos radicais livres causam a lipoperoxidação da membrana plasmática dos gametas feminino e masculino e dos embriões cultivados in vitro, sendo responsável por perda da produção in vitro de embriões e redução da fertilidade in vivo. O estudo foi realizado com objetivo de investigar o efeito protetor do diluidor de sêmen contendo antioxidante submetido à criopreservação e avaliado por testes complementares (teste de termo resistência, hiposmótico e fluorescência), pela inseminação artificial e fertilização in vitro. Ejaculados de cinco touros foram agrupados nos seguintes tratamentos: 1 - Diluidor Tris - gema (controle - Dil C); 2 - Diluidor Tris -gema + Trolox 200mM (antioxidante-Dil T). Amostras com os diluidores com concentração final de 25 x 106 espermatozóides/ palheta foram envasadas em palhetas de 0,25 mL. Em uma fazenda localizada no Mato Grosso do Sul - MS, foram inseminadas 300 novilhas Nelore, e para cada touro realizou-se 60 inseminações artificiais (palhetas descongeladas em 35°C por 20 seg). Oócitos com citoplasma homogêneo e cumulus compacto de ovário de vacas de abatedouro foram selecionados e maturados em grupos de 25 por gota em 100μl de meio TCM 199 com SFB, FSH, hCG e estradiol, piruvato de sódio e amicacina, por 24 horas, sob óleo mineral, e foram cultivados com 5% CO2 e 95% umidade em ar, a 38,5ºC. Depois da maturação, os oócitos foram colocados em gotas com TALP contendo BSA, PHE e 10μg/ml de heparina com 1x 106 espermatozóides móveis por ml. Quatro palhetas (duas - DC e duas - DT) do mesmo touro e ejaculado foram descongeladas e cada palheta foi processada por um método de separação espermática para recuperação do sobrenadante: método de lavagem (duas centrifugações de 36xg por 5 min em 2ml de TL-sêmen) e gradiente de Percoll (45 e 90%, submetido a centrifugação a 500xg por 30 min)...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Deleterious effects of free radicals cause lipoperoxidation of the plasmatic membrane of female and male gametes and in vitro cultured embryos, being responsible for losses in in vitro production of embryos and reduction in in vivo fertility. The objective of this study was to investigate the protective effects of semen extender containing antioxidant submitted to cryopreservation and evaluated by artificial insemination, in vitro fertilization and complementary tests (hyposmotic, fluorescence, and thermal resistance tests). Ejaculates from 5 bulls were treated with Tris egg yolk extender (control-CE) alone or supplemented with 200ml Trolox in the extender (antioxidant-AE). The samples with the extenders with a final concentration of 25 x 106 spermatozoa/ml were placed into 0.25 ml straws. Three hundred Nelore heifers from a cattle farm in Mato Grosso do Sul - MS, were separated into 5 groups of 60 animals. For artificial insemination, the straws were thawed at 35°C for 20 sec and the females in each group were inseminated with semen of the same bull, using 30 female for each semen extender treatment. For in vitro fertilization, oocytes with homogeneous cytoplasm and compact cumulus, collected from ovaries of slaughtered cows were selected and maturated in groups of 25 in droplets of 100μl TCM 199 medium with FCS, FSH, hCG and estradiol, sodium pyruvate and amicacin, for 24 hours, under mineral oil, in atmosphere of 5% CO2 and 95% humidity in air, at 38.5ºC. After maturation, the oocytes were placed in droplets with TALP containing BSA, PHE and 10μg/ml of heparin with 1x 106 motile spermatozoa/ml...(Complete abstract, click electronic access below) / Orientador: Paulo Henrique Franceschini / Coorientador: Antônio Cláudio Tedesco / Banca: Joaquim Mansano Garcia / Banca: César Roberto Esper / Banca: Sony Dimas Bicudo / Banca: José Domingos Guimarães / Doutor
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Modelování dodavatelských řetězců / Supply chain managementLašková, Jana January 2007 (has links)
Práce se zabývá empirickým ověřením platnosti efektu biče u reálného dodavatelského řetězce. Zároveň na reálných datech ukazuje rozdíl mezi optimalizací zásob každého dílčího článku řetězce a optimalizací zásob podél celého řetězce. Součástí práce je vytvořená učební pomůcka pro ukázku optimalizace zásob (model EOQ) a Pivní hra pro demonstraci platnosti efektu biče.
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Touradas, toureiros e morteMozer, Mariana Calvo 25 February 2011 (has links)
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Previous issue date: 2011-02-25 / The present paper develops the analysis of the figurative presences in the work of Frederico Garcia Lorca. For this ,it is used as corpus for the analysis the work of Llanto by Ignácio Sanchez Meijas, wherein the author proposes through the bullfight ceremony the vision of the death. Constituting this ceremony as the basis of the paper, we will focus on the study of the symbolic figures-the moon, the blood, the flowers, the colors red and white, the bull, the stone, the wind etc.. by focusing on the presence of the death as the main reason of this work. / O presente trabalho desenvolve a análise de presenças figurativas na obra de Federico Garcia Lorca. Para tanto, utiliza-se, como corpus de análise a obra Llanto por Ignácio Sanchez Mejías, em que autor propõe, por meio do ritual da tourada, a visão de morte. Constituindo este ritual a base do trabalho, vamos nos deter no estudo das suas figuras simbólicas a lua, o sangue, as flores, as cores vermelho e branco, o touro, a pedra, o vento, entre outros, afim de enfocar a presença da morte como motivo principal desta obra.
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A Multi-Scale Investigation of Factors Limiting Bull Trout ViabilityBowerman, Tracy 01 May 2013 (has links)
Effective conservation strategies for imperiled species require an understanding of processes that influence fitness throughout the organism's life cycle and across the range of habitats needed to complete that cycle. I evaluated factors that affect population viability of bull trout Salvelinus confluentus, a threatened freshwater char species, throughout individual life stages and over the entire life cycle. I assessed the relationship between bull trout egg incubation success and environmental variables. Egg survival was negatively related to the percent of fine sediment in redds and positively related to hydraulic conductivity and the strength of downwelling. Next, I quantified juvenile bull trout survival rates and described movement patterns for this life stage. Juvenile bull trout emigrated from natal headwaters into larger rivers throughout the entire year and across a range of sizes. Estimates of juvenile survival rates improved dramatically when emigration was incorporated into the analysis. I integrated my observations of bull trout survival, growth, and movement to create a life-cycle model, which I used to better understand how populations respond to changes in specific demographic rates. Bull trout populations were particularly sensitive to changes in juvenile growth and survival. The relative effect of changes to fertility rates and adult survival varied depending upon whether a population was composed primarily of large, migratory, or smaller, resident individuals. Dispersal helped to lower the probability of extinction for small or declining populations when neighboring populations were stable. My research demonstrates that bull trout require access to habitats throughout entire watersheds to maintain population viability. My results suggest that limiting anthropogenic sources of fine sediment and maintaining areas of channel complexity that promote downwelling can be important for bull trout embryo survival. Management decisions should also consider the diverse behavior of juvenile bull trout and the wide range of habitat they use. Additionally, connectivity between populations is likely to be important for declining populations to persist. The diversity of life-history strategies expressed by bull trout helps maintain demographic stability within and among populations. As such, preservation of habitat integrity and full life-history diversity is imperative for conservation and recovery of bull trout populations range-wide.
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Lowering Sperm Dose Rates in Frozen Semen for Bovine Artificial BreedingPitt, Colin John January 2007 (has links)
The New Zealand Dairy industry relies on artificial breeding to produce high genetic merit replacement stock. Proven bull semen is extended and preserved as either ambient temperature product or as frozen doses. High fertility is essential to maintain synchronicity of lactation with the spring surge of grass growth. To improve efficiency in the utilization of the very best bulls producers try to lower sperm dose rates without compromising fertility. Livestock Improvement Corporation's (LIC) Long Last Liquid ™ (LLL) is most commonly used during the peak season and is their most important product. However, shortfalls and specifically targeted matings are met with frozen semen. Lowering sperm dose rates in both liquid and frozen semen maximises the usage of elite sires increasing genetic gain, lowering overheads and garnering premium prices for the semen producer. A product for improving frozen semen technology was developed whereby a discrete quantity of pretreated semen was placed alongside a beneficial post-thawing redilution medium in a standard semen straw. This emulated a larger-scale process developed to freeze semen in times of low demand and redilution into the LLL form for use as an ambient temperature product. This rediluted product has been proved to enhance semen survival and to allow fertility to be maintained at sperm dose rates lower than the widely accepted standard for frozen semen. The physical packaging of the semen into the industry standard single dose straw in a configuration that separated incompatible components was novel. This configuration was essential to prevent damage to the sperm during the freezing process from low solubility components in the post-thaw redilution medium. Separation between the semen and diluent within the straw was achieved by the introduction of a gas partition or air bubble between the two liquids. A large-scale field trial showed that the new product could produce savings of up to 25% of the sperm needed for a semen dose to achieve equivalent fertility. Furthermore, the production cost per dose was lowered in comparison to the standard semen processing system used at LIC.
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Cryopreservation of bovine semen in egg yolk based extenders2013 February 1900 (has links)
Cryopreservation of germplasm is widely used in agriculture, biotechnology, conservation of threatened species and human reproductive medicine. There is a need however to improve the reproductive efficiency of breeding with cryopreserved semen, which may involve increasing the post-thaw quality of sperm through improvements in cryopreservation extenders. Extenders including egg yolk from chickens are successfully used worldwide for cryopreservation of bovine semen, whereas the protective agent in the egg yolk is believed to be the low-density lipoprotein (LDL) fraction. Egg yolks of different avian species vary in their cholesterol, phospholipid and polyunsaturated fatty acid content which have been shown to have important effects on sperm’s freezing capability. The purpose of this study was to determine the cryoprotective effect of clarified egg yolk and LDLs extracted from different egg yolk sources (chicken, chicken omega-3, pigeon, quail and turkey) on bovine sperm. Semen from six bulls was collected four times each by electroejaculation, split and diluted with the 10 following extenders: chicken clarified (Ccl), chicken omega-3 clarified (O3cl), pigeon clarified (Pcl), quail clarified (Qcl), turkey clarified (Tcl), chicken LDL (CLDL), chicken omega-3 LDL (O3LDL), pigeon LDL (PLDL), quail LDL (QLDL) and turkey LDL (TLDL). The extended semen was evaluated, cryopreserved and examined directly after thawing (0h) and after two hours at 37 ˚C (2h). Computer assisted sperm analysis (CASA) was used to determine total sperm motility (TM), progressive motility (PM), straight line velocity (VSL), curvilinear velocity (VCL) and average path velocity (VAP). Intact plasma membrane (IPM) and intact acrosomes (IA) were measured by flow cytometry. The percentage change (loss; Δ%) of each sperm characteristic was calculated and used to compare the effect of the extenders. From extending to 0h post-thaw, the pigeon LDL extender lead to greater losses in sperm total and progressive motility, as well as of intact acrosomes, than the other nine extenders tested (P < 0.05). During 0h to 2h post-thaw, the sperm in PLDL extender experienced greater losses in total and progressive motility (P < 0.0001), as well as in curvilinear velocity (P < 0.05), than in all the other nine extenders. Sperm in turkey clarified extender had a greater loss in the velocity parameters (VSL, VAP, VCL) than sperm in several of the other extenders such as O3cl, CLDL, O3LDL, QLDL and TLDL from 0h to 2h (P < 0.05). Concomitantly, sperm in the Tcl extender had a greater loss in the velocity parameters and of intact acrosomes compared to sperm in its counterpart, the turkey LDL extender, from 0h to 2h post-thaw (P < 0.05).
The differences produced in post-thaw quality of cryopreserved bovine sperm in the pigeon LDL and turkey clarified extenders were attributed to methodological differences in these egg yolk preparations compared with the other eight extenders.
Importantly, the results demonstrate that with most egg yolk preparations derived from a variety of species, there are equivalent cryoprotective effects afforded by the use of omega-3 chicken, pigeon, quail, or conventional chicken egg yolk in a clarified form in freezing extenders for bovine semen. We further proved that the freezing capabilities of bovine semen extenders containing the low-density lipoprotein fraction of omega-3 chicken, quail, turkey and conventional chicken egg yolk were similar.
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A Multi-Scale Investigation of Factors Limiting Bull Trout ViabilityBowerman, Tracy 01 May 2013 (has links)
Effective conservation strategies for imperiled species require an understanding of processes that influence fitness throughout the organism's life cycle and across the range of habitats needed to complete that cycle. I evaluated factors that affect population viability of bull trout Salvelinus confluentus, a threatened freshwater char species, throughout individual life stages and over the entire life cycle. I assessed the relationship between bull trout egg incubation success and environmental variables. Egg survival was negatively related to the percent of fine sediment in redds and positively related to hydraulic conductivity and the strength of downwelling. Next, I quantified juvenile bull trout survival rates and described movement patterns for this life stage. Juvenile bull trout emigrated from natal headwaters into larger rivers throughout the entire year and across a range of sizes. Estimates of juvenile survival rates improved dramatically when emigration was incorporated into the analysis. I integrated my observations of bull trout survival, growth, and movement to create a life-cycle model, which I used to better understand how populations respond to changes in specific demographic rates. Bull trout populations were particularly sensitive to changes in juvenile growth and survival. The relative effect of changes to fertility rates and adult survival varied depending upon whether a population was composed primarily of large, migratory, or smaller, resident individuals. Dispersal helped to lower the probability of extinction for small or declining populations when neighboring populations were stable. My research demonstrates that bull trout require access to habitats throughout entire watersheds to maintain population viability. My results suggest that limiting anthropogenic sources of fine sediment and maintaining areas of channel complexity that promote downwelling can be important for bull trout embryo survival. Management decisions should also consider the diverse behavior of juvenile bull trout and the wide range of habitat they use. Additionally, connectivity between populations is likely to be important for declining populations to persist. The diversity of life-history strategies expressed by bull trout helps maintain demographic stability within and among populations. As such, preservation of habitat integrity and full life-history diversity is imperative for conservation and recovery of bull trout populations range-wide.
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