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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.
1

A retrospective study on the geographical distribution of cholera in Limpopo Province, South Africa

Selamolela, S. D. January 2016 (has links)
Thesis (MPH.) -- University of Limpopo, 2016 / Introduction: During mid-November 2008, eleven acute watery diarrhoea cases with the suspicion of cholera like symptoms were detected by a diarrhoea surveillance system at Musina Hospital in Vhembe district - Limpopo Province, South Africa. These cases included eight Zimbabwean and three South African citizens. Laboratory test performed on stool specimens confirmed Vibrio cholerae serogroup 01 Ogawa as the causative pathogen for these reported acute watery diarrhoea cases. Within eight weeks of its onset, the outbreak spread to all the five districts of Limpopo. So far between 15 November 2008 and 01 June 2009, the cumulative number of cases of acute watery diarrhoea reported from five districts of Limpopo Province stands at 4634 including 30 confirmed cholera deaths with an overall case fatality rate of 0.65%. Of these reported cases, Vibrio cholerae has been laboratory confirmed in 656 samples. Methodology: A database was received from the Limpopo Department of Health having all reported cholera cases during the 2008 and 2009 outbreak in Limpopo Province. The data was analysed using STATA statistical software version 12 for windows (STATA Corporation, College Station, Texas). Results: The cholera affected all ages, but the geographic distribution of the disease was very heterogeneous in Limpopo Province. The highest and lowest numbers of cases were reported in Capricorn and Mopani districts, respectively. The majority of the cases 55% (N=2 542) were females. Children less than five years of age 14.2% (N=652) were less affected by the disease. About 73.8% of the cases were aged between O and 44 years. The first four weeks of cholera outbreak strictly included a day-to-day admixture of Zimbabweans and South Africans presenting in the health facilities. The outbreak then affected most South Africans after week five of the epidemic. Conclusion: The cholera outbreak has affected all the five districts of Limpopo Province in South Africa, and new cases continued to be reported until first week of June 2009. There was a link between the Zimbabwean and South African cholera outbreak in Limpopo province.
2

International Clostridium difficile animal strain collection and large diversity of animal associated strains

Janezic, Sandra, Zidaric, Valerija, Pardon, Bart, Indra, Alexander, Kokotovic, Branko, Blanco, Jose, Seyboldt, Christian, Diaz, Cristina, Poxton, Ian, Perreten, Vincent, Drigo, Ilenia, Jiraskova, Alena, Ocepek, Matjaz, Weese, J., Songer, J., Wilcox, Mark, Rupnik, Maja January 2014 (has links)
BACKGROUND:Clostridium difficile is an important cause of intestinal infections in some animal species and animals might be a reservoir for community associated human infections. Here we describe a collection of animal associated C. difficile strains from 12 countries based on inclusion criteria of one strain (PCR ribotype) per animal species per laboratory.RESULTS:Altogether 112 isolates were collected and distributed into 38 PCR ribotypes with agarose based approach and 50 PCR ribotypes with sequencer based approach. Four PCR ribotypes were most prevalent in terms of number of isolates as well as in terms of number of different host species: 078 (14.3% of isolates / 4 hosts), 014/020 (11.6% / 8 hosts) / 002 (5.4% / 4 hosts) and 012 (5.4% / 5 hosts). Two animal hosts were best represented / cattle with 31 isolates (20 PCR ribotypes / 7 countries) and pigs with 31 isolates (16 PCR ribotypes / 10 countries).CONCLUSIONS:This results show that although PCR ribotype 078 is often reported as the major animal C. difficile type, especially in pigs, the variability of strains in pigs and other animal hosts is substantial. Most common human PCR ribotypes (014/020 and 002) are also among most prevalent animal associated C. difficile strains worldwide. The widespread dissemination of toxigenic C. difficile and the considerable overlap in strain distribution between species furthers concerns about interspecies, including zoonotic, transmission of this critically important pathogen.
3

Examining sufficiency and equity in the geographic distribution of physicians in Japan: a longitudinal study / 日本の医師数地域分布における充足度と格差の検証 : 縦断研究

Hara, Koji 26 March 2018 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(社会健康医学) / 甲第21032号 / 社医博第86号 / 新制||社医||10(附属図書館) / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 古川 壽亮, 教授 川上 浩司, 教授 黒田 知宏 / 学位規則第4条第1項該当
4

Revisão taxonômica e filogenia de Astrodoradinae (Siluriformes,Doradidae) / Taxonomic revision and phylogeny of Astrodoradinae (Siluriformes, Doradidae)

Leandro Melo de Sousa 19 November 2010 (has links)
As espécies da subfamília Astrodoradinae foram revisadas e uma análise filogenética conduzida. Foram reconhecidas 21 espécies distribuídas em sete gêneros. Acanthodoras e Agamyxis, outrora considerados próximos a Platydoras foi considerado sinônimo ju nior de A. weddellii e uma nova espécie é descrita do alto Araguaia. Os gêneros Merodoras e Physopyxis foram considerados sinônimos A. ananas, A. bolivarensis, A. cristatus, A. lyra e A. nheco. Duas novas espécies de Astrodoras são reconhecidas, ocorrendo sintopicamente com A. asterifrons em alguns lugares da bacia amazônica. Scorpiodoras calderonensis é revalidado e sua localidade tipo elucidada, revelando-se ser Tabatinga. Além disso, uma nova espécie de Scorpiodoras foi descrita no médio rio Madeira. A análise cladística foi feita com base em 101 caracteres codificados para 28 táxons, resultando em uma única árvore mais parcimoniosa com 279 passos. O monofiletismo de Astrodoradinae foi sustentado por sete sinapomorfias não exclusivas: fontanela craniana anterior oval ou circular, número reduzido de costelas (oito ou menos), coracóide não coberto completamente por musculatura ventral, número reduzido de vértebras (34 ou menos), para-hipural fusionado aos hipurais 1 e 2, infra-orbital 1 participando da órbita e terceiro escudo timpânico expandido. Anadoras é considerado o gênero mais basal de Astrodoradinae, seguido por (Acanthodoras + Agamyxis) (Amblydoras (Scorpiodoras (Hypodoras + Astrodoras))). / The species of the subfamily Astrodoradinae was revised and a phylogenetic analysis performed. Twenty-one species, belonging to seven genera, are recognized as valid. Acanthodoras and Agamyxis, formely considered to be related to Platydoras,are included into Astrodoradinae. Anadoras regani is considered as a junior synonym of A. weddellii and a new species is described from the upper Araguaia. The genera Merodoras and Physopyxis are placed in synonym with Amblydoras,which has six valid species: A. affinis, A. ananas, A. bolivarensis, A. cristatus, A. lyra and A. nheco.Two new species of Astrodoras are described and occur syntopically in some places in the Amazon basin. Scorpiodoras calderonensis is reerected and its type locality elucidated as Tabatinga. Furthermore, a new species of Scorpiodoras is discribed from the middle rio Madeira. The cladistic analysis was performed based on 101 characters coded for 28 taxa and resulted in a single most parcimonious tree with 279 steps. The monophyly of Astrodoradinae is supported by seven non-exclusive synapomorphies: anterior cranial fontanel oval or circular, reduced number of ribs (eigth or less), ventral face of coracoid not completely covered by muscles, reduced number of vertebrae (34 or less), parhypural fused to hipural 1 and 2, infra-orbital 1 participating of orbit and third tympanic scute expanded. Anadoras is considered the most basal genus of Astrodoradinae, followed by (Acanthodoras + Agamyxis)(Amblydoras (Scorpiodoras (Hypodoras + Astrodoras))).
5

Faunística e distribuição geográfica de hidróides bentônicos (Cnidaria, Hydrozoa) do sudoeste do Atlântico / Faunistic and geographic distribution of benthic hydroids (Cnidaria, Hydrozoa) from southwestern Atlantic

Thaís Pires Miranda 07 December 2009 (has links)
O aprofundamento de estudos faunísticos e taxonômicos é essencial para a inferência de áreas de distribuição geográfica e, conseqüentemente, de áreas de endemismo. Estes estudos são incipientes para o ambiente marinho, incluindo o sudoeste do Atlântico, particularmente em relação aos cnidários. Os principais objetivos deste estudo foram (1) levantar a fauna de hidróides bentônicos da região entre Cabo Frio (Brasil) e Terra do Fogo (Argentina) e (2) inferir a distribuição geográfica das espécies levantadas, buscando uma eventual caracterização de áreas de endemismo. No total, 181 morfoespécies de hidróides foram registradas, sendo que destas, 10 são registros novos para a região (Aglaophenia trifida, Antennella secundaria, Cryptolarella abyssicola, Filellum contortum, Lafoea coalescens, Lovenella gracilis, Macrorhynchia grandis, ?Nemertesia ciliata, Sertullarella leiocarpa e Zygophylax sibogae) e 9 são espécies endêmicas (Corymorpha januarii, Ectopleura obypa, Eudendrium caraiuru, Hydractinia uniformis, Lytocarpia canepa, Parascyphus repens, Plumularia insignis, Ralpharia sanctisebastiani, Symplectoscyphus magellanicus) para a área. A riqueza de espécies teve uma pequena diminuição com o aumento da latitude e diminuiu drasticamente em águas mais profundas (abaixo das isóbatas de 100 e 1000m). A análise de PCA demonstrou que os substratos Algae, Hydrozoa, Mollusca, Porifera e Rocha apresentaram os maiores números de ocorrência de morfoespécies de hidróides. A análise de cluster resultou na delimitação de três grupos de fauna: (1) brasileiro costeiro, (2) uruguaio-argentino e (3) oceânico contínuo por toda a área amostrada. Em relação às áreas de endemismo, as análises com o NDM-VNDM resultaram em duas principais áreas endêmicas costeiras para o litoral do Brasil (entre 22-24°S 43-46°W e entre 26-29°S 48-49°W), sendo que a metodologia PAE resultou em quatro áreas endêmicas para a região de estudo: (1) áreas costeiras contínuas para o Brasil ou Argentina; (2) áreas costeiras e contínuas entre o Brasil e Argentina; (3) áreas oceânicas contínuas entre Cabo Frio e Terra do Fogo; (4) áreas restritas à região do rio da Prata. Nossos resultados revelaram que a correspondência entre as faunas de profundidade brasileira e de regiões mais rasas do litoral argentino pode estar relacionada com o regime de frentes oceânicas atuantes no sudoeste do Atlântico. Além disso, análises incluindo exclusivamente espécies de hidróides que produzem medusa em seus ciclos de vida resultaram em áreas de endemismo mais restritas à costa em relação às espécies que formam somente gonóforos fixos. Estes resultados contradizem o paradigma clássico que associa a presença de medusa com a alta capacidade dispersiva das espécies. / Increasing on faunistic and taxonomic knowledge is essential for reliable inferences on the geographical distribution and, consequently, on areas of endemism. This knowledge is incipient for the marine realm, including southwestern Atlantic, and particularly poor for cnidarians. The main goal of this study was (1) to survey the fauna of benthic hydroids from the region between Cabo Frio (Brasil) and Terra do Fogo (Argentina), and (2) to infer the geographic distribution of the surveyed species, aiming to propose areas of endemism. A total of 181 morphospecies of hydroids was recorded, 10 species are new records (Aglaophenia trifida, Antennella secundaria, Cryptolarella abyssicola, Filellum contortum, Lafoea coalescens, Lovenella gracilis, Macrorhynchia grandis, ?Nemertesia ciliata, Sertullarella leiocarpa e Zygophylax sibogae) and 9 are endemic species (Corymorpha januarii, Ectopleura obypa, Eudendrium caraiuru, Hydractinia uniformis, Lytocarpia canepa, Parascyphus repens, Plumularia insignis, Ralpharia sanctisebastiani, Symplectoscyphus magellanicus) for the area. Species richness slightly decreases along higher latitudes and along deeper waters (below 100 and 1000m isobaths). A PCA analyses has demonstrated that the substrata, Algae, Hydrozoa, Mollusca, Porifera and Rock showed a higher number of morphospecies of hydroids. Cluster analysis resulted in three faunistic groups: (1) Brazilian-coastal, (2) Uruguayan-Argentinean and (3) and oceanic group continuous along the entire surveyed area. Concerning areas of endemism, NDM-VNDM analyses resulted in two main coastal areas of endemism on the Brazilian coast (between 22-24°S 43-46°W and between 26-29°S 48- 49°W), and PAE resulted in four areas of endemism for the studied area: (1) coastal area in Brazil or Argentina; (2) a coastal and continuous area along Brazil and Argentina; (3) an oceanic and continuous area; (4) a Rio de La Plata area. Our results have shown that faunal affinities between Brazilian deep fauna and Argentinean shallow water fauna might be related to the marine fronts present in the southwestern Atlantic. Moreover, analyses exclusively including hydroid species with medusa in the life cycle resulted in more limited areas of endemism closer to the coast than those analyses exclusively including hydroids species with fixed gonophores. These results contradict the classical paradigm associating the presence of medusa and higher dispersive capabilities of the species.
6

Revisão taxonômica e filogenia de Astrodoradinae (Siluriformes,Doradidae) / Taxonomic revision and phylogeny of Astrodoradinae (Siluriformes, Doradidae)

Sousa, Leandro Melo de 19 November 2010 (has links)
As espécies da subfamília Astrodoradinae foram revisadas e uma análise filogenética conduzida. Foram reconhecidas 21 espécies distribuídas em sete gêneros. Acanthodoras e Agamyxis, outrora considerados próximos a Platydoras foi considerado sinônimo ju nior de A. weddellii e uma nova espécie é descrita do alto Araguaia. Os gêneros Merodoras e Physopyxis foram considerados sinônimos A. ananas, A. bolivarensis, A. cristatus, A. lyra e A. nheco. Duas novas espécies de Astrodoras são reconhecidas, ocorrendo sintopicamente com A. asterifrons em alguns lugares da bacia amazônica. Scorpiodoras calderonensis é revalidado e sua localidade tipo elucidada, revelando-se ser Tabatinga. Além disso, uma nova espécie de Scorpiodoras foi descrita no médio rio Madeira. A análise cladística foi feita com base em 101 caracteres codificados para 28 táxons, resultando em uma única árvore mais parcimoniosa com 279 passos. O monofiletismo de Astrodoradinae foi sustentado por sete sinapomorfias não exclusivas: fontanela craniana anterior oval ou circular, número reduzido de costelas (oito ou menos), coracóide não coberto completamente por musculatura ventral, número reduzido de vértebras (34 ou menos), para-hipural fusionado aos hipurais 1 e 2, infra-orbital 1 participando da órbita e terceiro escudo timpânico expandido. Anadoras é considerado o gênero mais basal de Astrodoradinae, seguido por (Acanthodoras + Agamyxis) (Amblydoras (Scorpiodoras (Hypodoras + Astrodoras))). / The species of the subfamily Astrodoradinae was revised and a phylogenetic analysis performed. Twenty-one species, belonging to seven genera, are recognized as valid. Acanthodoras and Agamyxis, formely considered to be related to Platydoras,are included into Astrodoradinae. Anadoras regani is considered as a junior synonym of A. weddellii and a new species is described from the upper Araguaia. The genera Merodoras and Physopyxis are placed in synonym with Amblydoras,which has six valid species: A. affinis, A. ananas, A. bolivarensis, A. cristatus, A. lyra and A. nheco.Two new species of Astrodoras are described and occur syntopically in some places in the Amazon basin. Scorpiodoras calderonensis is reerected and its type locality elucidated as Tabatinga. Furthermore, a new species of Scorpiodoras is discribed from the middle rio Madeira. The cladistic analysis was performed based on 101 characters coded for 28 taxa and resulted in a single most parcimonious tree with 279 steps. The monophyly of Astrodoradinae is supported by seven non-exclusive synapomorphies: anterior cranial fontanel oval or circular, reduced number of ribs (eigth or less), ventral face of coracoid not completely covered by muscles, reduced number of vertebrae (34 or less), parhypural fused to hipural 1 and 2, infra-orbital 1 participating of orbit and third tympanic scute expanded. Anadoras is considered the most basal genus of Astrodoradinae, followed by (Acanthodoras + Agamyxis)(Amblydoras (Scorpiodoras (Hypodoras + Astrodoras))).
7

The geographic distribution of ticks in the eastern region of the Eastern Cape Province

Nyangiwe, Nkululeko 12 May 2008 (has links)
The objective of the study was to determine the species composition and geographic distribution of ticks in the eastern region of the Eastern Cape Province. Ninety out of a total of 1 057 communal cattle dip-tanks in the region were selected by means of a table of random numbers, and 72 of these were eventually allocated to the survey. At each of the chosen dip-tanks an attempt was made to collect ticks from five cattle, five goats, five dogs and two hen coops, and free-living ticks from the vegetation by means of flannel strips, and ticks were collected from January 2004 and 2005 to May 2004 and May 2005 respectively. The geographic coordinates of the dip-tanks at which the ticks were collected were recorded, and used for plotting the distributions of the various tick species. The ticks were stored in 70 % ethyl alcohol in internally labelled vials for later identification and counting. Eleven ixodid tick species were collected from cattle, goats, dogs and the vegetation, namely Amblyomma hebraeum, Haemaphysalis elliptica, Haemaphysalis spinulosa, Hyalomma marginatum rufipes, Ixodes pilosus group, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus (Boophilus) microplus, Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus sanguineus and Rhipicephalus simus. Of these R. e. evertsi and R. appendiculatus were the most numerous, and constituted 38.8 % and 34.9% of the 13 768 ticks collected respectively. They were followed by R. (B.) microplus (17.4 %) and A. hebraeum (5.3%). Two argasid tick species were collected, namely Otobius megnini from the ear canals of two cattle, and Argas walkerae from fowl houses. A. walkerae was collected from 102 (70.8%) of 144 fowl houses in the vicinity of 57 (79.2%) of the 72 selected dip-tanks, and seemed to be present only when there was wood in the structure of the fowl house. Adult A. hebraeum was present in areas where there are trees and bush as well as grass, particularly along the coast, but also surprisingly far inland beyond the distribution limits previously illustrated for it. R. (B.) microplus, R. appendiculatus and R. e. evertsi were present throughout the survey area region, and from their distribution maps there are strong indications that the exotic R. (B.) microplus is displacing the indigenous R. (B.) decoloratus in this region. A large percentage of goats were infested with the adults of ticks normally associated with cattle, namely A. hebraeum, R. (B.) microplus, R. appendiculatus and R. e. evertsi. A more significant finding, however, is the large proportion of R. (B.) microplus females measuring 5 mm or more in length on the goats, a good indication that they were successfully completing their life cycles. In the light of these findings, it is imperative to include goats in any tick control programme aimed at controlling a tick-borne disease outbreak in sympatric cattle. Eight ixodid tick species were collected from the dogs, and H. elliptica, followed by R. appendiculatus and R. simus were present on these animals at the largest number of dip-tanks. The kennel tick R. sanguineus, a parasite of dogs in urban environments, was collected from dogs only at two localities. / Dissertation (MSc (Veterinary Science))--University of Pretoria, 2007. / Veterinary Tropical Diseases / MSc / unrestricted
8

Environmental control of radiolarian abundance in the Central Equatorial Pacific and implications for paleoceanographic reconstructions

Welling, Leigh A. 03 September 1996 (has links)
Graduation date: 1997
9

Fallstudie för Fishbrain AB : Användarundersökningar för framtagandet av personas där användarna har en geografisk spridning / Case study for Fishbrain AB : User-research for the development of personas where the users have a large geographical distribution

Sundstedt, Sara, Rytterlund, Sofia January 2017 (has links)
This study is a case study for a mobile app for fishing enthusiasts, Fishbrain with the purpose of presenting personas based on user-research. This assignment was carried out upon request of Fishbrain as the company finds that they lack qualitative data. One main reason for this is that the majority of the users are located in the US. Fishbrain has 4.83 million users mainly across the United States, Australia, Sweden and Brazil (14th of December 2017). This study intends to determine whether our chosen methods for user-research can apply when the interviewers and the responders are located at different geographical locations, and to evaluate if our chosen method for deriving personas can be applied on a large user base. This study is based on quantitative data collected through surveys. Subsequently, interviews were conducted as a method for collecting more qualitative data. Based on this empirical foundation, interesting insights and recurring factors were categorized. Two primary personas and two secondary personas were developed from this analysis. This study finds that our chosen methods for user-research are valid when users and researchers are located in different places, but that there are certain limitations that the researchers should take into consideration, for example the time difference. This may require a longer research timeframe  than if the research is conducted in a lab environment. / Denna undersökning är en fallstudie för Fishbrain med syfte att presentera personas framtagna utifrån användarundersökningar. På önskan av Fishbrain genomfördes detta uppdrag då företaget upplever att de saknar kvalitativ data, eftersom majoriteten av användarna befinner sig i USA. Fishbrain har 4,83 miljoner användare fördelat över främst USA, Australien, Sverige och Brasilien (2017-12-14). Med denna studie hoppas vi kunna svara på huruvida våra valda metoder för användarundersökningar är lämpliga då undersökare och deltagare befinner sig på olika geografiska platser, samt att utvärdera huruvida vår valda metod för framtagande av personas kan appliceras på en stor användarbas. Undersökningen utgår från kvantitativt insamlad data från enkätundersökningar. Därefter används intervju som metod för att komma åt mer kvalitativa aspekter. Utifrån denna empiriska grund kategoriseras olika intressanta insikter och återkommande faktorer. Vid analys av datainsamlingen utvecklas två primära samt två sekundära personas. Undersökningens slutsats är att det är applicerbart att genomföra användarundersökningar när användarna och undersökarna befinner sig på olika platser, men att det finns vissa begränsningar som undersökarna bör ta hänsyn till, såsom tidsskillnad. Dessa begränsningar medför att den tidsram som sätts för projektet bör beräknas längre än om undersökningarna genomförs i laboratoriemiljö.
10

Understanding the Effects of Demographic and Socio-Economic Factors on Public Transit Ridership Trends

Lehmann, Kurt 23 March 2018 (has links)
Public transit, an important mobility service for many, has incurred ridership decline in the U.S. for the past three years. In 2014, U.S. transit ridership was 10.74 billion unlinked passenger trips. In 2015, total ridership was 1.0 percent fewer, and the 2016 decrease was 2.2 percent from 2015. The consistent abandonment of transit in the U.S. does not seem to be ending. In 2017, ridership predicted from year-to-date data is 2.4 percent less than 2016. Furthermore, per capita ridership has decreased 17 percent since 1980. Both the short-term ridership trend and long-term per capita ridership trend is concerning given the increased spending and service provision during the same periods. In seeking to understand the many factors that influence transit ridership trends, it is important to analyze each so that policymakers and practitioners can respond and position transit accordingly. Numerous demographic and economic phenomena help explain this decline in transit use. This research focuses on five of these considerations – age, vehicle availability, telecommuting, fuel price, and geographical distribution of the population.

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