Bibliografías temáticas / Bad breath / Tesis
Siga este enlace para ver otros tipos de publicaciones sobre el tema: Bad breath.

Tesis sobre el tema "Bad breath"

Autor: Grafiati
Publicado: 4 de junio de 2021
Última modificación: 28 de julio de 2024

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros

Elija tipo de fuente:

Consulte los 47 mejores tesis para su investigación sobre el tema "Bad breath".

Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.

También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.

Explore tesis sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.

1

Leung, Chun-fung Albert. "Aetiological, behavioural and cultural features of halitosis in a Hong Kong population /". [Hong Kong : Faculty of Dentistry], the University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19902190.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
2

Ellis, Ryan. "Bad breath response to tongue scraper and rinses". Diss., Search in ProQuest Dissertations & Theses. UC Only, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1465480.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
3

Im, Terry. "Bad breath response to tongue scraper and rinses". Diss., Search in ProQuest Dissertations & Theses. UC Only, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1465483.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
4

Johansson, Birgit. "Bad breath : prevalence, periodontal disease, microflora and inflammatory markers /". Huddinge, 2005. http://diss.kib.ki.se/2005/91-7140-295-0/.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
5

Leung, Chun-fung Albert y 梁晉峰. "Aetiological, behavioural and cultural features of halitosis in a HongKong population". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31215646.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
6

De, Ciccio Angela. "Oral spirochetes : contribution to oral malodor and formation of spherical bodies". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0004/MQ29679.pdf.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
7

Ruat, Gabrielle Rodrigues. "A VIVÊNCIA DA HALITOSE E SUAS IMPLICAÇÕES NO COMPORTAMENTO DE ADULTOS". Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/6101.

Texto completo
Resumen
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Smell has a close connection with the brain areas involving emotion, learning and memory, and maybe that's why the olfactory memories evoke emotions. In dentistry, some situations involving the presence of unpleasant odors can cause some discomfort, such as halitosis, popularly known as bad breath. Halitosis is defined as an offensive odor from the mouth, nasal cavities, sinuses and / or pharynx. This study aimed to understand how halitosis is experienced by individuals and detect their reflections on the behavior of the ill. For this, we used a qualitative methodology and data collection was performed at the School of Dentistry, Federal University of Santa Maria. The study population consisted of twelve adult individuals of both sexes and complaining of halitosis. The study group was considered sufficient when information began to repeat, indicating saturation of the data. This qualitative research used semistructured interviews as a procedure for data collection. After each interview, information was transcribed and submitted to the analysis. To interpret the data and better understand the meanings, we used the technique of content analysis, thematic modality. The analysis included categories that were expected and those that emerged. After the analysis, we obtained six categories lated to halitosis: "Bad breath is a horrible smell," "I feel very bad, in desperation," "Talk is losing his friend," "I became addicted to chewing gum," "Healing: a watershed in my life" and "The dental professionals should be prepared. " We noticed that people associate factors of oral and gastrointestinal disturbances as a possible cause of halitosis. About behavioral, people who have this change often feel inferior and rejected, avoiding social contact. All prefer to be alerted about oral malodor by friends and / or family, however, would not warn others about the same condition. Still, there was plenty of resources that use masking breath and see the dentist as the main responsible for diagnosing and treating halitosis, and found little information available about this. Thus, we conclude that halitosis is a change that could affect self-esteem and confidence of the people, a negative effect on social behavior, and that the issue requires action halitosis wide range of multi population in order to clarify doubts and myths related to its etiology and its treatment.
O olfato tem uma ligação próxima com as áreas cerebrais que envolvem a emoção, o aprendizado e a memória, e talvez seja por isso que as memórias olfativas evoquem emoções. Em Odontologia, algumas situações que envolvem presença de odores desagradáveis podem causar algum desconforto, como é o caso da halitose, popularmente chamada de mau hálito. A halitose é definida como um odor ofensivo proveniente da boca, cavidades nasais, seios da face e/ou faringe. Este estudo teve como objetivo compreender como a halitose é vivenciada pelas pessoas e detectar os seus reflexos no comportamento dos acometidos. Para isso, utilizou-se uma metodologia qualitativa e a coleta dos dados foi realizada nas dependências do Curso de Odontologia da Universidade Federal de Santa Maria. A população de estudo foi constituída por doze indivíduos adultos de ambos os sexos e com queixa de halitose. O grupo de estudo foi considerado suficiente quando as informações começaram a se repetir, indicando a saturação dos dados. Esta investigação qualitativa utilizou entrevistas individuais semiestruturadas como procedimento para coleta dos dados. Após cada entrevista, as informações eram integralmente transcritas para posterior submissão à análise. Para interpretar os dados e melhor compreender os significados, foi utilizada a técnica de Análise de Conteúdo, na modalidade temática. A análise incluiu temas que eram esperados e também os que emergiram durante o trabalho. Após a análise, foram obtidas seis categorias relacionadas à halitose: Mau hálito é um cheiro horrível ; Eu me sinto muito mal, em desespero ; Falar é perder o amigo ; Eu viciei em chicletes ; Cura: um divisor de águas na minha vida e Os profissionais da Odontologia deveriam estar preparados . Foi possível verificar que as pessoas associam fatores intrabucais e distúrbios gastrintestinais como possível causa da halitose. Do ponto de vista comportamental, os indivíduos que apresentam essa alteração frequentemente sentem-se inferiorizados e rejeitados, evitando o convívio social. Todos preferem ser alertados sobre o mau odor bucal pelos amigos e/ou familiares, entretanto, não avisariam a outras pessoas sobre a mesma condição. Ainda, observou-se que utilizam abundantemente recursos mascaradores do hálito e veem o cirurgião-dentista como o principal responsável por diagnosticar e tratar a halitose, e consideram escassas as informações disponíveis sobre o assunto. Assim, concluímos que halitose é uma alteração capaz de afetar a autoestima e a autoconfiança das pessoas, interferindo negativamente no comportamento social, e que o tema halitose requer ações multiprofissionais de ampla abrangência populacional a fim de esclarecer dúvidas e mitos referentes à sua etiologia e ao seu tratamento.
Los estilos APA, Harvard, Vancouver, ISO, etc.
8

Soares, Léo Guimarães. "Efeito do tratamento periodontal full-mouth e convencional na redução da halitose". Universidade do Estado do Rio de Janeiro, 2013. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=6402.

Texto completo
Resumen
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A halitose se caracterizada pela emanação de um odor desagradável onde cerca de 90% de se origina dentro da cavidade oral. Estudos têm demonstrado uma relação direta entre a doença periodontal e o odor ofensivo do hálito. O presente estudo teve como objetivo avaliar a frequência e distribuição de halitose em um grupo de pacientes com doença periodontal em um estudo transversal observacional (n=112) e, em um estudo intervencionista, avaliar o efeito do tratamento periodontal full-mouth e convencional na redução da halitose em um grupo de pacientes com doença periodontal. Os pacientes responderam a uma anamnese, tiveram seu hálito mensurado pelo halímetro e teste organoléptico, além de realizados Índice de placa visível, Índice de sangramento gengival, Índice de saburra lingual e exame periodontal completo. No estudo 2, os pacientes foram submetidos a seis distintas formas de tratamento: terapia periodontal em sessão única, terapia convencional em quadrantes e, um grupo controle, com somente instrução de higiene oral. Todas as modalidades subdivididas: com e sem raspagem lingual diária. No primeiro estudo os resultados mostraram que, tanto para teste organoléptico quanto para o halímetro, houve maior grau de halitose nos grupos de idades mais avançadas, nos que relataram sangramento gengival e escovação menos que três vezes ao dia. Ainda no teste organoléptico a escovação de língua gerou diferença estatística. Não houve diferença estatística entre as medidas de halitose entre teste organoléptico e halímetro. Foram encontrados aproximadamente 75% de pacientes periodontais com halitose. No segundo estudo os resultados mostraram superioridade conforme análise do halímetro para 30, 60 e 90 dias para os grupos de raspagem em sessão única contra raspagem por quadrantes. Sendo todos os grupos superiores ao controle. Não houve diferença na abordagem com ou sem a raspagem de língua. De acordo com o teste organoléptico, não houve diferença entre os quatro tipos de tratamento periodontal comparados aos grupos controle. O mesmo aplica-se ao WTCI, onde os grupos de tratamento foram superiores ao controle, todavia semelhantes entre si. Concluiu-se que a idade e o sangramento gengival, assim como a frequência de escovação podem influenciar no grau de halitose, tanto no teste organoléptico quanto halímetro. A escovação de língua mostrou-se superior apenas na avaliação organoléptica. Quando avaliado através do halímetro o tratamento full-mouth foi superior ao tratamento convencional. Esta diferença não foi observada quando avaliado através do método organoléptico. Todas as modalidades de tratamento periodontal foram superiores aos grupos controle. A raspagem lingual não teve influência nos tratamentos.
Halitosis is characterized by the emission of an unpleasant odor about 90% originates in the oral cavity. Studies have shown a direct relationship between periodontal disease and the offensive odor of breath. The present study aimed to determine the prevalence of halitosis in patients with periodontal disease in an observational cross-sectional study (n = 112) and, in an intervention study, the patients have had six distinct forms of treatment (n = 90) to verify the efficacy of full- vs. partial-mouth disinfection in the control of halitosis. Patients answered an interview, they have had their breath collected by halimeter, they have evaluated by organoleptic test, and visible plaque index, gingival bleeding index, index of tongue coating and periodontal examination. In the second step, patients have been submitted to six different forms of treatment: periodontal therapy in one session, conventional therapy in quadrants, and the control group, with only oral hygiene instruction. All types split: with and without tongue scraping daily. The first study results shown for both organoleptic test as halimeter, a greater degree of halitosis in the older age groups, we have reported that gum bleeding and brushing less than three times per day. Still in organoleptic test brushing of tongue generated statistical difference. There was no statistical difference between the measures between halitosis and organoleptic test halimeter. There was about 75% og periodontal patients with halitosis. In the second study the results shown the superiority analysis as halimeter for 30, 60 and 90 days for groups of scraping in single session against scraping by quadrants. Being all groups superior from control. There was no difference in approach with or without tongue scraping. According to the organoleptic test, there was no difference between the four types of periodontal treatment compared to the control groups. The same applies to WTCI, the treatment groups were superior to the control, but similar to each other. It was concluded that age and gingival bleeding, like brushing frequency can influence the degree of halitosis, both the organoleptic test as halimeter. Brushing the tongue was superior only in organoleptic evaluation. When assessed by halimeter treatment full-mouth was superior to conventional treatment. This difference was not observed when measured by the organoleptic method. All periodontal treatment modalities were superior to control groups. Scraping lingual had no influence on treatments.
Los estilos APA, Harvard, Vancouver, ISO, etc.
9

Queiroz, Celso Silva. "Avaliação da relação entre estresse e a concentração de compostos sulfurados volateis no halito bucal". [s.n.], 1999. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289296.

Texto completo
Resumen
Orientador: Jaime Aparecido Cury
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-07-25T22:05:28Z (GMT). No. of bitstreams: 1 Queiroz_CelsoSilva_M.pdf: 4148499 bytes, checksum: a250fc32bc9b3c95e74bc4505b1ca920 (MD5) Previous issue date: 1999
Resumo: O objetivo do trabalho foi avaliar a relação entre o estresse e a concentração dos compostos sulfurados voláteis (CSV) no hálito bucal. Para tanto, foram avaliadas duas condições estressantes: Estudo I - prova; Estudo II - tensão pré-menstrual (TPM). O Estudo I foi composto de 2 grupos: A e B. O grupo A (34 voluntários), foi subdividido em 18 voluntários com estresse e 16 voluntários sem estresse. As concentrações dos CSV e foram medidas 1 semana antes da prova, no dia e 1 semana após, através do monitor de sulfetos (Halimeter) e o fluxo salivar também foi mensurado. No grupo B (37 voluntários), além dessas análises foram mensurados o pH, "capacidade tampão", cálcio, fósforo e proteína na saliva. O Estudo II foi composto por 50 voluntárias: 27 mulheres sem TPM (controle) e 23 mulheres com TPM. As mensurações dos CSV e do fluxo salivar foram realizadas nos períodos não-menstrual, pré-menstrual e de menstruação. A análise estatística mostrou que tanto no Grupo A (n=34) quanto no Grupo B (n=37) a concentração dos CSV no dia da prova foi maior (p<0,05) enquanto que a taxa de fluxo salivar foi menor (p<0,05). Os voluntários com estresse (n=18) e sem estresse (n=16) também apresentaram maiores concentrações de CSV no dia da prova (p<0,05), enquanto o fluxo salivar foi menor somente nos voluntários não estressados (p<0,05). A análise bioquímica da saliva do Grupo B revelou - que o pH foi menor no dia da prova (p<0,05), e as demais análises não foram diferentes (p>0,05). No Estudo II, as voluntárias sem TPM (n=26) apresentaram maior concentração dos CSV no período menstrual (p<0,05). Enquanto nas voluntárias com TPM (n=23) a concentração dos CSV foi maior (p<0,05) nos períodos menstrual e pré-menstrual. Já o fluxo salivar não mostrou diferenças (p>0,05). Os resultados sugerem que o estresse é um fator pré-disponente da halitose, cujo mecanismo não pode ser explicado somente pela diminuição do fluxo salivar
Abstract:The aim of study was to evaluate the relationship between stress and volatile sulfur compounds (VSC) present in mouth air. Thus, two stressfull conditions were evaluated: Study 1- examination; Study II - premenstrual syndrome (PMS). Study I was composed of 2 groups: A and B. Group A (34 volunteers), was divided in 18 volunteers with stress and 16 volunteers without stress. VSC concentrations were measured a week before, on day and a week after the exam using a sulfide monitor (Halimeter) and the salivary flow was measured. In group B (37 volunteers), others analyisis as pH, "buffer capacity", proteins, calcium and phosphorus, in saliva were performed. In study II, fifty women were selected: 27 women without PMS symptoms (control group) and 23 women with PMS symptoms. The measurements were performed during non-menstrual, PMS and menstrual periods. The statistical results showed in both groups A and B an increase of VSC concentration on the exam day (p<0.05) and the salivary flow was lower (p<0.05). Volunteers with stress (n=18) and without stress (n=16), presented higher VSC concentration on the exam (p<0.05), but there was statistical diferences in the salivary flow rate only in the volunteers without stress (p<0.05). The biochemistry analisys of the saliva in group B showed that pH was lower on the exam day (p<0.05), and others analisys were not statistical differences (p>0.05). In study II, the volunteers without PMS symptoms (n=26) presented higher VSC concentration in the menstrual period (p<0.05). Volunteers with PMS (h=23) showed a greater VSC concentration in both menstrual and PMS periods (p<0.05). Salivary flow rate was not statistically different (p>0.05). The results suggest that stressful conditions can be a predisposing factor for bad breath, and the mechanism cannot be explained only by the decrease of the salivary flow
Mestrado
Fisiologia Oral
Mestre em Odontologia
Los estilos APA, Harvard, Vancouver, ISO, etc.
10

Bordbar, Kaveh. "Kunskap om och upplevelse av halitosis samt klinisk mätning av svavelhaltiga gaser bland gymnasieelever". Thesis, Kristianstad University, School of Health and Society, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-6993.

Texto completo
Resumen

The aim of this study is to examine the knowledge and experience of the bad breath among high school students in Kristianstad. A further objective was to measure the amount of VSC (Volatile Sulfur Compounds) among those who perceive themselves to have a bad breath. A questionnaire with 21 closed questions was distributed to 120 high school students from Kristianstad municipality who were between the ages of 17-20. The results of this study revealed that most of the students had good knowledge of halitosis. The majority of all participants thought it was important to smell fresh in the mouth and also experienced most of their breath as very good or good. Only a few felt that they had bad breath. However, these persons did think their breath affect their everyday life. Furthermore, they have never felt embarrassed or caught in embarrassing situations due to their breath. The results from the clinical examination was carried out on 8 of the 120 students and was designed to measure the amount of sulphurous gases in the oral cavity which revealed that the average values that emerged in the examination below is the limited values for having a poor breath.


Syftet med denna studie var att undersöka kunskapen och upplevelsen av dålig andedräkt hos gymnasieelever i Kristianstad, ytterligare ett syfte var att mäta mängden VSC (reaktiva svavelföreningar)  hos dem som upplever sig ha dålig andedräkt. En enkät med 21 slutna frågor delades ut till 120 gymnasieelever som var mellan 17-20 år och studerade i Kristanstads kommun. Av resultatet i denna studie framkom att de flesta av gymnasieeleverna hade goda kunskaper om halitosis. Nästan alla 120 som besvarade enkäten tyckte att det var viktigt att lukta fräsch i munnen och dessutom upplevde de flesta sin andedräkt som mycket bra eller bra. Endast ett fåtal (14% ) kände att de ibland hade dålig andedräkt. Hos dessa  påverkades inte andedräkten deras vardagliga liv och de hade aldrig blivit generade eller hamnat i pinsamma situationer på grund av sin andedräkt. Resultatet från den kliniska undersökningen som gjordes på 8 av de 120 elever som besvarade enkäten där mängden av de svavelhaltiga gaserna i munhålan mättes visade att i genomsnitt ligger värden som framkom i undersökningen under gränsvärden för att man skall ha dålig andedräkt.

Los estilos APA, Harvard, Vancouver, ISO, etc.
11

Hall, Emma. "Benign breast disease as a risk factor for breast cancer". Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322197.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
12

Neilson, James Christian. "Integrity of Storage Media for Clinical Applications with SIFT-MS Instruments". Thesis, University of Canterbury. Mechanical Engineering, 2006. http://hdl.handle.net/10092/2579.

Texto completo
Resumen
Tedlar™ bags are a promising medium for remote breath collection and later analysis using SIFT-MS for disease diagnosis. It is important to understand the changes in integrity of samples stored in Tedlar™ bags. However, there is little work into this problem completed to date, and thus little known about these issues. Therefore, a study into the integrity of samples stored in Tedlar™ bags and analysed using SIFT-MS was undertaken. The sample integrity of ammonia, acetone, ethanol, isoprene and pentane, all initially at 3ppm in breath and nitrogen substrates, and stored in Tedlar™ bags was investigated. Experiments tested the effect of storage size (0.5, 1, 3L), storage time (6-48 hours), storage temperature (23℃ - 25℃, 37℃), humidity (0.4 - 4.5% absolute) and inter-bag variation using triplicate bags. The SIFT-MS instrument used was LDI2 located at Christchurch Hospital. The repeatability and precision of LDI2 was established using prepared cylinder samples (0.05% absolute humidity) of acetone, pentane and ethanol tested at seven times over a 250 min time period. A generalised Cauchy distribution was used to give a combined distribution from multiple bags for the sample humidity and compound concentration. A combined measure of the repeatability and precision, T s , ranged between 217 - 349 ppb for ethanol, acetone and pentane. The factors affecting the repeatability and precision were both machine and compound dependant. The effect of the factors differed over time, with different precursors and compounds. No obvious effects of bag storage size on the sample integrity of pentane, isoprene, ethanol and acetone were observed. The absolute humidity change within bag samples was linked to the volume to surface area ratio because it was more affected by permeation and condensation. All compounds in the nitrogen substrate (except for 37℃ stored acetone (NO+)) displayed decreases in sample integrity with time. All compounds in the breath substrate displayed regular losses of sample integrity, except for the 37℃ and 23℃ - 25℃ stored ethanol (NO+) and 37℃ stored ethanol (H3O+), pentane (O2+) and ammonia (H3O+, O2+). The average change of sample integrity for pentane, isoprene, ethanol and acetone ranged from 0.2 to 3.6 times the maximum T s , while ammonia ranged from 0.9 - 10 times. All observed behaviour was reproducible. Absolute humidity and storage temperature affected the sample integrity of acetone, ethanol and ammonia. Generally, the intra-bag variance was comparable between all storage temperatures and substrates while the inter-bag variation was affected by the absolute humidity. Only the initial and final concentrations between precursors for the 23℃ - 25℃ stored breath and nitrogen substrates agreed. The breath substrate samples gave erroneous values for ammonia. Permeation of compounds into the bags from the atmosphere was not significant. The overall issues surrounding storing breath in Tedlar™ bags for analysis using SIFTMS is not the loss of sample integrity, but the kinetics, precision and repeatability of the SIFT-MS instrument. The current kinetics are not adequate to accurately monitor acetone, isoprene, pentane, ammonia and ethanol in breath and stored in Tedlar™ bags at breath absolute humidity levels greater than 3%. Generally, the loss of sample integrity was only marginally outside the repeatability and precision of the machine.
Los estilos APA, Harvard, Vancouver, ISO, etc.
13

Larson, Jennifer Mary. "The Good, the Bad and the Cunning: How Networks Make or Break Cooperation". Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10171.

Texto completo
Resumen
Groups often find themselves in a position to self-govern: sometimes a formal governing apparatus is weak or nonexistent; sometimes the legal system is underdeveloped, heavily back-logged or inapplicable; and sometimes groups simply have a preference for informal processes. In such cases, contrary to the Hobbesian vision of a self-help nightmare, groups often fare remarkably well both cooperating internally and coexisting with other groups. Diffuse punishment institutions induce cooperation well in tight-knit groups: the theory is well-understood and empirical examples abound. In many realistic settings, though, groups are imperfectly tight-knit, especially when populations are large or sparse or when communications technology is poor (even Facebook networks with very low-cost links are incomplete). Here I relate cooperation to a group's exact structure of communication to identify the role that networks play in making or breaking cooperation. By generalizing the game-theoretic model in Fearon and Laitin (1996), I present a model flexible enough to account for the various ways that a group may be imperfectly tight-knit.
Government
Los estilos APA, Harvard, Vancouver, ISO, etc.
14

Cutress, Ramsey Ian. "BAG 1 expression and function in breast cancer". Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289513.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
15

Van, Tassel William Edward. "An evaluation of pocket-model, numerical readout breath alcohol testing instruments". Texas A&M University, 2003. http://hdl.handle.net/1969.1/1159.

Texto completo
Resumen
Eight small-scale breath alcohol measurement devices were tested for accuracy, precision and the ability to not yield false positive and false negative readings. These pocket-sized breath testers (PMBTs), which provided numerical readout of BrAC to the 100th of a percent, were smaller than evidential and preliminary breath test instruments (EBTs and PBTs). The smallest devices were approximately the same size of a cigarette lighter. Designed to provide drinkers feedback about their individual alcohol levels, the PMBTs ranged in price from $40-100 USD. The devices were first tested under laboratory conditions with alcohol solution simulators providing the alcoholic samples. They were then tested with human drinkers, under controlled field conditions. Each device was tested at multiple alcohol levels. Two of the eight PMBTs failed to complete all levels of testing and were excluded from the study. All PMBTs demonstrated the ability to not yield false positive and false negative readings. No device met NHTSA performance criteria for accuracy (systematic error) in testing EBTs at every alcohol level tested. An interaction between PMBTs and the alcohol test levels was found. Thus, accuracy was found to be dependent upon the alcohol level at which the devices were tested. No device met NHTSA performance criteria for precision in testing EBTs at every alcohol level tested. Precision varied depending on the testing condition. There was less precision under controlled field conditions than under laboratory conditions. Five of the six PMBTs that completed the testing overestimated BrAC; only one device read below actual BrAC. Ramifications of the findings are discussed, regarding the overestimation and underestimation of BrAC and the possibility of manufacturers intentionally calibrating the devices to overestimate BrAC. Potential PMBT users are discussed and areas for future research are addressed.
Los estilos APA, Harvard, Vancouver, ISO, etc.
16

Clark, Cammi. "When Bad Genes Ruin a Perfectly Good Outlook: Psychological Implications of Hereditary Breast and Ovarian Cancer via Narrative Inquiry Methodology". Antioch University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1565254126257837.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
17

Lee, Matthew Allen. "ANALYSIS OF BREAST LESIONS USING A SIMPLIFIED RUBBER BAND STRAIGHTENING TRANSFORM AND THE ONION TRANSFORM". MSSTATE, 2006. http://sun.library.msstate.edu/ETD-db/theses/available/etd-11262006-092433/.

Texto completo
Resumen
This thesis compares different methods that could be used to construct a computer aided diagnosis (CAD) system that analyzes mammograms. Such systems have many steps, but this thesis focuses on feature extraction, feature selection, and classification. The main comparison is between the simplified Rubber Band Straightening Transform (SRBST) and the Onion Transform, which are used to extract texture features. Another comparison is between 2D and 3D co-occurrence matrices. Next, features are selected using a greedy algorithm. This section mainly compares the effectiveness of Receiver Operating Characteristic (ROC) and Class Overlap Rating (COR). Also evaluated are the effectiveness of Linear Discriminate Analysis (LDA) and the sort order of features. Then the selected features are used to classify the lesions. In this part, Nearest Mean, Nearest Neighbor, and Maximum Likelihood are compared. The results are then used to determine the best combination of methods to use in a CAD system.
Los estilos APA, Harvard, Vancouver, ISO, etc.
18

Vogel, Stefanie [Verfasser], Ilko [Akademischer Betreuer] Bald, Thomas [Akademischer Betreuer] Schlathölter y Steen Brøndsted [Akademischer Betreuer] Nielsen. "Sequence dependency of photon and electron induced DNA strand breaks / Stefanie Vogel ; Ilko Bald, Thomas Schlathölter, Steen Brøndsted Nielsen". Potsdam : Universität Potsdam, 2018. http://d-nb.info/121945799X/34.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
19

Frère, Laura. "Les microplastiques : une menace en rade de Brest ?" Thesis, Brest, 2017. http://www.theses.fr/2017BRES0046/document.

Texto completo
Resumen
Depuis plusieurs décennies la production mondiale de plastiques ne cesse d’augmenter, menant à une contamination des écosystèmes aquatiques à l’échelle de la planète qui a été récemment estimée à plus de cinq mille milliards de débris de plastiques flottants à la surface des océans. Les microplastiques (particules de plastique < 5 mm), introduits dans l’environnement aquatique directement en tant que microparticules (granulés plastiques industriels, cosmétiques, fibres textiles) ou lors de la fragmentation de plus gros débris plastiques, représentent une préoccupation scientifique et sociétale grandissante. Ces travaux de thèse se sont focalisés sur la contamination par les microplastiques de la rade de Brest (Bretagne, France), un système côtier macrotidal où l’activité anthropique est importante. Les objectifs de ces travaux sont (1) d’évaluer la contamination des matrices environnementales (eau de surface, sédiment subtidal et biote) par les microplastiques, et (2) d’identifier leur rôle potentiel en tant que vecteurs de contaminants chimiques et de bactéries dans la rade de Brest.Pour cela, des développements analytiques ont été nécessaires afin d’améliorer leur extraction des matrices environnementales ainsi que leur caractérisation morphologique et chimique via la microspectrométrie Raman. Les observations in situ ont montré que l’ensemble de l’écosystème de la rade de Brest est contaminé par les microplastiques, avec des concentrations de 0,24 ± 0,35, et 0,97 ± 2,08 (moyenne ± écart-type). L’eau de surface et le sédiment sont contaminés par le polyéthylène, le polypropylène et le polystyrène. Leur distribution à la surface de l’eau semble être liée à l’urbanisation très présente au nord de la rade, mais également à l’hydrodynamisme de cette région marine. Les premiers résultats concernant les bivalves marins ont montré un niveau relativement faible de contamination par les microplastiques (0,01 ± 0,04 et 0,08 ± 0,34 pour les moules et les coques, respectivement), cependant cela est probablement dû aux choix méthodologiques appliqués ici (exclusion des fibres). Les observations in situ ont montré que certains polluants organiques (HAP, PCB et pesticides) étaient détectés sur les microplastiques flottants à des valeurs (non détecté – 49763 ng.g-1, moyenne ± écart-type) similaires de celles retrouvées dans les sédiments et les bivalves locaux, ce qui suggère un risque faible dans le transfert des contaminants chimiques vers les organismes marins en cas d’ingestion. Enfin, les résultats concernant la colonisation bactérienne des microplastiques flottants ont montré des communautés distinctes de celles retrouvées dans l’eau de mer environnante, et l’identification du genre Vibrio en tant que biomarqueur discriminant de cette matrice. Dans l’ensemble, ces travaux fournissent une première évaluation approfondie de l’état de contamination de la rade de Brest par les microplastiques ainsi que de solides recommandations méthodologiques pour des travaux futurs
World production of plastics has increased steadily for the past decades leading to a major contamination of the worldwide aquatic ecosystems recently estimated at more than five trillion plastic pieces floating the surface of the oceans. Microplastics (plastic particles < 5 mm) are introduced into aquatic environments directly as industrial raw material (plastic pellets, cosmetics, clothing) or indirectly via the fragmentation of larger plastics. This emerging contaminant represents an increasing ecological concern for science and society. The present study focused on the microplastic contamination of the Bay of Brest (Brittany, France), a macrotidal coastal ecosystem characterized by intense anthropogenic activity. The main objectives were: (1) to evaluate the contamination of environmental matrices (surface water, subtidal sediment and biota) by microplastics, and (2) to identify their potential role as vector of chemicals and bacteria in the bay of Brest.Methodological developments were first conducted to improve microplastic extraction from environmental matrices as well as their rapid morphological and chemical identification by Raman micro-spectrometry. The field investigations showed that the ecosystem of the bay of Brest is contaminated by microplastics with mean concentrations of 0.24 ± 0.35, and 0.97 ± 2.08 (mean ± standard deviation) in surface water and sediment, respectively. Microplastic contamination in surface water and sediment was dominated by polyethylene, polypropylene and polystyrene microparticles.Spatial microplastic distribution appeared to be related to proximity to urbanized areas and to hydrodynamic in the bay. Preliminarily results of microplastic contamination in marine bivalves demonstrated relatively low contamination (0.01 ± 0.04, and 0.08 ± 0.34 for mussels and cockles, respectively) by microplastics (mainly polyethylene and polypropylene fragments), however this could be partly related to the methodological limitation identified here (e.g. exclusion of fibers). Organic pollutant (PAH, PCB and pesticides) were detected on floating microplastics at levels (not detected – 49,763 ng g-1, mean ± SD) similar to those measured in sediment and bivalves suggesting low risks in transferring hazardous chemicals in local marine organisms upon microplastic ingestion. Finally, distinct bacterial community assemblages were demonstrated on microplastics as compared with surrounding surface water; the Vibrio genus was identified as a discriminant biomarker of the plastic matrix. Overall, this work provides a first and thorough assessment of the microplastic contamination in the bay of Brest and solid methodological recommendations for further work
Los estilos APA, Harvard, Vancouver, ISO, etc.
20

Abbink, Albertine Alie. "Make it and break it : the cycles of pottery : a study of the technology, form, function, and use of pottery from the settlements at Uitgeest-Groot Dorregeest and Schagen-Muggenburg 1, Roman period, North-Holland, the Netherlands /". Leiden : Faculty of archaeology, Leiden university, 1999. http://catalogue.bnf.fr/ark:/12148/cb37211134q.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
21

Ebel, Kenny [Verfasser], Ilko [Akademischer Betreuer] Bald, Ilko [Gutachter] Bald, Adrian [Gutachter] Keller y Marie [Gutachter] Davídková. "Quantification of low-energy electron induced single and double strand breaks in well-defined DNA sequences using DNA origami nanostructures / Kenny Ebel ; Gutachter: Ilko Bald, Adrian Keller, Marie Davídková ; Betreuer: Ilko Bald". Potsdam : Universität Potsdam, 2021. http://d-nb.info/1234058731/34.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
22

Androuin, Thibault. "Ecologie trophique de l'espèce ingénieur Crepidula fornicata et implications pour le fonctionnement de son habitat". Thesis, Brest, 2018. http://www.theses.fr/2018BRES0106.

Texto completo
Resumen
La crépidule (Crepidula fornicata) est une espèce invasive des côtes européennes. Hermaphrodite protandre, cette espèce grégaire forme des chaines d’individus qui s’accumulent en forte densité sur les fonds. Longtemps considérée comme un envahisseur néfaste, la crépidule est aussi un ingénieur de l’écosystème, modifiant physiquement et biologiquement son habitat. Elle constitue un modèle biologique pour étudier comment les espèces invasives et ingénieurs peuvent structurer et modifier l’écosystème qu’elles colonisent. Dans le cadre de cette thèse, ces effets ont été examinés à travers le fonctionnement trophique des habitats à crépidules, en lien notamment avec la production primaire benthique. Il a été mis en évidence expérimentalement une stimulation du microphytobenthos (MPB) subtidal grâce à l’activité biologique de la crépidule. La niche trophique de C. fornicata a été redéfinie suite à la découverte de la présence de sphérules de carbonates dans ses tissus, surestimant la contribution du MPB dans son régime alimentaire. L’utilisation de différents marqueurs trophiques (pigments, acides gras, isotopes) a révélé que les jeunes individus mobiles étaient susceptibles de brouter le MPB associé au biofilm présent sur les coquilles. Les adultes sessiles, sont des filtreurs opportunistes, où la matière détritique mais aussi du MPB contribuent à leur régime alimentaire. L’analyse de différents suspensivores inféodés à cet habitat, a démontré que la crépidule n’était pas un compétiteur trophique pour des espèces commercialement importantes (pétoncle noir et huître plate) dû à leurs mécanismes de sélection trophique. À l’échelle du réseau trophique, la crépidule en très forte densité peut conduire à une homogénéisation du réseau trophique global dû à l’enrichissement en matière organique. Au contraire, un banc mort de crépidules montre une complexité trophique similaire à celle d’un banc de maërl, écosystème à forte biodiversité. Cette thèse, en plus d’avoir caractérisé le fonctionnement trophique des bancs de crépidules, montre qu’une espèce invasive, en facilitant certains compartiments biologiques (MPB, suspensivores), peut contribuer à la richesse d’un écosystème comme celui la rade de Brest
The slipper limpet (Crepidula fornicata) is an invasive species of European coasts. Protandric hermaphrodite, this gregarious species forms individuals' stacks which accumulate in high density on bottom. For a long time considered as a detrimental invader, the slipper limpet is also an ecosystem engineer, modifying its habitat both physically and biologically. It is model to study how invasive and engineer species can structure and modify the ecosystem that they colonize. In this Ph.D. thesis, these effects have been examined through the trophic functioning of habitats colonized by the slipper limpet, with a special reference to the primary benthic production. Experimental stimulation of subtidal microphytobenthos (MPB) has been demonstrated by the biological activity of the slipper limpet.The trophic niche of C. fornicata has been redefined following the discovery of the presence of carbonate spherules in its tissues, overestimating the contribution of MPB in its diet. Several trophic markers use (pigments, fatty acids, isotopes)revealed that young motile individuals were likely to graze the MPB associated to shell biofilm. Sessile adults, were likely opportunistic filter-feeders, where detritus but also MPB contribute to their trophic diet. The analysis of several filter-feeders inhabiting Crepidula beds has demonstrated that the slipper limpet was not a trophic competitor for commercially important species (black scallop and flat oyster) due to their trophic sorting mechanisms. At the food web scale, the high density of slipper limpet can lead to a homogenization of the global food web due to organic matter enrichment. Dead Crepidula bed showed trophic complexity similar to maerl bed, which is a high biodiverse ecosystem. This thesis, in addition to characterize the trophic functioning of Crepidula beds, shows that an invasive species, in facilitating different biological compartments (MPB, filter-feeders), can contribute to the ecosystem richness such as the Bay of Brest
Los estilos APA, Harvard, Vancouver, ISO, etc.
23

Massich, Joan. "Segmentation d'objets déformables en imagerie ultrasonore". Thesis, Dijon, 2013. http://www.theses.fr/2013DIJOS090/document.

Texto completo
Resumen
Le cancer du sein est le type de cancer le plus répandu, il est la cause principale de mortalité chez les femmes aussi bien dans les pays occidentaux que dans les pays en voie de développement. L'imagerie médicale joue un rôle clef dans la réduction de la mortalité du cancer du sein, en facilitant sa première détection par le dépistage, le diagnostic et la biopsie guidée. Bien que la Mammographie Numérique (DM) reste la référence pour les méthodes d'examen existantes, les échographies ont prouvé leur place en tant que modalité complémentaire. Les images de cette dernière fournissent des informations permettant de différencier le caratère bénin ou malin des lésions solides, ce qui ne peut être détecté par DM. Malgré leur utilité clinique, les images échographiques sont bruitées, ce qui compromet les diagnostiques des radiologues à partir de celles ci. C'est pourquoi un des objectifs premiers des chercheurs en imagerie médicale est d'améliorer la qualité des images et des méthodologies afin de simplifier et de systématiser la lecture et l'interprétation de ces images.La méthode proposée considère le processus de segmentation comme la minimisation d'une structure probabilistique multi-label utilisant un algorithme de minimisation du Max-Flow/Min-Cut pour associer le label adéquat parmi un ensemble de labels figurant des types de tissus, et ce, pour tout les pixels de l'image.Cette dernière est divisée en régions adjacentes afin que tous les pixels d'une même régions soient labelisés de la même manière en fin du processus. Des modèles stochastiques pour la labellisation sont crées à partir d'une base d'apprentissage de données
Breast cancer is the second most common type of cancer being the leading cause of cancer death among females both in western and in economically developing countries. Medical imaging is key for early detection, diagnosis and treatment follow-up. Despite Digital Mammography (DM) remains the reference imaging modality, Ultra-Sound (US) imaging has proven to be a successful adjunct image modality for breast cancer screening, specially as a consequence of the discriminative capabilities that US offers for differentiating between solid lesions that are benign or malignant. Despite US usability,US suffers inconveniences due to its natural noise that compromises the diagnosis capabilities of radiologists. Therefore the research interest in providing radiologists with Computer Aided Diagnosis (CAD) tools to assist the doctors during decision taking. This thesis analyzes the current strategies to segment breast lesions in US data in order to infer meaningful information to be feet to CAD, and proposes a fully automatic methodology for generating accurate segmentations of breast lesions in US data with low false positive rates
Los estilos APA, Harvard, Vancouver, ISO, etc.
24

Scarfe, Bradley Edward. "Oceanographic Considerations for the Management and Protection of Surfing Breaks". The University of Waikato, 2008. http://hdl.handle.net/10289/2668.

Texto completo
Resumen
Although the physical characteristics of surfing breaks are well described in the literature, there is little specific research on surfing and coastal management. Such research is required because coastal engineering has had significant impacts to surfing breaks, both positive and negative. Strategic planning and environmental impact assessment methods, a central tenet of integrated coastal zone management (ICZM), are recommended by this thesis to maximise surfing amenities. The research reported here identifies key oceanographic considerations required for ICZM around surfing breaks including: surfing wave parameters; surfing break components; relationship between surfer skill, surfing manoeuvre type and wave parameters; wind effects on waves; currents; geomorphic surfing break categorisation; beach-state and morphology; and offshore wave transformations. Key coastal activities that can have impacts to surfing breaks are identified. Environmental data types to consider during coastal studies around surfing breaks are presented and geographic information systems (GIS) are used to manage and interpret such information. To monitor surfing breaks, a shallow water multibeam echo sounding system was utilised and a RTK GPS water level correction and hydrographic GIS methodology developed. Including surfing in coastal management requires coastal engineering solutions that incorporate surfing. As an example, the efficacy of the artificial surfing reef (ASR) at Mount Maunganui, New Zealand, was evaluated. GIS, multibeam echo soundings, oceanographic measurements, photography, and wave modelling were all applied to monitor sea floor morphology around the reef. Results showed that the beach-state has more cellular circulation since the reef was installed, and a groin effect on the offshore bar was caused by the structure within the monitoring period, trapping sediment updrift and eroding sediment downdrift. No identifiable shoreline salient was observed. Landward of the reef, a scour hole ~3 times the surface area of the reef has formed. The current literature on ASRs has primarily focused on reef shape and its role in creating surfing waves. However, this study suggests that impacts to the offshore bar, beach-state, scour hole and surf zone hydrodynamics should all be included in future surfing reef designs. More real world reef studies, including ongoing monitoring of existing surfing reefs are required to validate theoretical concepts in the published literature.
Los estilos APA, Harvard, Vancouver, ISO, etc.
25

Frère, Laura. "Les microplastiques : une menace en rade de Brest ?" Electronic Thesis or Diss., Brest, 2017. http://www.theses.fr/2017BRES0046.

Texto completo
Resumen
Depuis plusieurs décennies la production mondiale de plastiques ne cesse d’augmenter, menant à une contamination des écosystèmes aquatiques à l’échelle de la planète qui a été récemment estimée à plus de cinq mille milliards de débris de plastiques flottants à la surface des océans. Les microplastiques (particules de plastique < 5 mm), introduits dans l’environnement aquatique directement en tant que microparticules (granulés plastiques industriels, cosmétiques, fibres textiles) ou lors de la fragmentation de plus gros débris plastiques, représentent une préoccupation scientifique et sociétale grandissante. Ces travaux de thèse se sont focalisés sur la contamination par les microplastiques de la rade de Brest (Bretagne, France), un système côtier macrotidal où l’activité anthropique est importante. Les objectifs de ces travaux sont (1) d’évaluer la contamination des matrices environnementales (eau de surface, sédiment subtidal et biote) par les microplastiques, et (2) d’identifier leur rôle potentiel en tant que vecteurs de contaminants chimiques et de bactéries dans la rade de Brest.Pour cela, des développements analytiques ont été nécessaires afin d’améliorer leur extraction des matrices environnementales ainsi que leur caractérisation morphologique et chimique via la microspectrométrie Raman. Les observations in situ ont montré que l’ensemble de l’écosystème de la rade de Brest est contaminé par les microplastiques, avec des concentrations de 0,24 ± 0,35, et 0,97 ± 2,08 (moyenne ± écart-type). L’eau de surface et le sédiment sont contaminés par le polyéthylène, le polypropylène et le polystyrène. Leur distribution à la surface de l’eau semble être liée à l’urbanisation très présente au nord de la rade, mais également à l’hydrodynamisme de cette région marine. Les premiers résultats concernant les bivalves marins ont montré un niveau relativement faible de contamination par les microplastiques (0,01 ± 0,04 et 0,08 ± 0,34 pour les moules et les coques, respectivement), cependant cela est probablement dû aux choix méthodologiques appliqués ici (exclusion des fibres). Les observations in situ ont montré que certains polluants organiques (HAP, PCB et pesticides) étaient détectés sur les microplastiques flottants à des valeurs (non détecté – 49763 ng.g-1, moyenne ± écart-type) similaires de celles retrouvées dans les sédiments et les bivalves locaux, ce qui suggère un risque faible dans le transfert des contaminants chimiques vers les organismes marins en cas d’ingestion. Enfin, les résultats concernant la colonisation bactérienne des microplastiques flottants ont montré des communautés distinctes de celles retrouvées dans l’eau de mer environnante, et l’identification du genre Vibrio en tant que biomarqueur discriminant de cette matrice. Dans l’ensemble, ces travaux fournissent une première évaluation approfondie de l’état de contamination de la rade de Brest par les microplastiques ainsi que de solides recommandations méthodologiques pour des travaux futurs
World production of plastics has increased steadily for the past decades leading to a major contamination of the worldwide aquatic ecosystems recently estimated at more than five trillion plastic pieces floating the surface of the oceans. Microplastics (plastic particles < 5 mm) are introduced into aquatic environments directly as industrial raw material (plastic pellets, cosmetics, clothing) or indirectly via the fragmentation of larger plastics. This emerging contaminant represents an increasing ecological concern for science and society. The present study focused on the microplastic contamination of the Bay of Brest (Brittany, France), a macrotidal coastal ecosystem characterized by intense anthropogenic activity. The main objectives were: (1) to evaluate the contamination of environmental matrices (surface water, subtidal sediment and biota) by microplastics, and (2) to identify their potential role as vector of chemicals and bacteria in the bay of Brest.Methodological developments were first conducted to improve microplastic extraction from environmental matrices as well as their rapid morphological and chemical identification by Raman micro-spectrometry. The field investigations showed that the ecosystem of the bay of Brest is contaminated by microplastics with mean concentrations of 0.24 ± 0.35, and 0.97 ± 2.08 (mean ± standard deviation) in surface water and sediment, respectively. Microplastic contamination in surface water and sediment was dominated by polyethylene, polypropylene and polystyrene microparticles.Spatial microplastic distribution appeared to be related to proximity to urbanized areas and to hydrodynamic in the bay. Preliminarily results of microplastic contamination in marine bivalves demonstrated relatively low contamination (0.01 ± 0.04, and 0.08 ± 0.34 for mussels and cockles, respectively) by microplastics (mainly polyethylene and polypropylene fragments), however this could be partly related to the methodological limitation identified here (e.g. exclusion of fibers). Organic pollutant (PAH, PCB and pesticides) were detected on floating microplastics at levels (not detected – 49,763 ng g-1, mean ± SD) similar to those measured in sediment and bivalves suggesting low risks in transferring hazardous chemicals in local marine organisms upon microplastic ingestion. Finally, distinct bacterial community assemblages were demonstrated on microplastics as compared with surrounding surface water; the Vibrio genus was identified as a discriminant biomarker of the plastic matrix. Overall, this work provides a first and thorough assessment of the microplastic contamination in the bay of Brest and solid methodological recommendations for further work
Los estilos APA, Harvard, Vancouver, ISO, etc.
26

Banton, Nicole Elaine. "Nipple Matters: A Black Feminist Analysis of the Politics of Infant Feeding among African American Mothers". Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/sociology_diss/39.

Texto completo
Resumen
During this unique moment of feminist inquiry wherein breastfeeding has been a focal point of interdisciplinary research, little sociological scholarship has been presented which has centered on the various meanings that African American mothers, as a diverse group, attach to their experiences with breastfeeding and/or infant formula use. While patterns of behavior have been explored in a cross-racial context, most social science studies have not focused on how the choice between breastfeeding, using infant formula, or using a combination of the two has impacted (or has been shaped by) African American mothers’ constructs of self, motherhood/mothering, their birth experiences, and their sexuality. In order to understand the interplay of the decision-making process and these constructs, I conducted a qualitative study in which I participated in face-to-face interviews with a diverse group of thirty African-American mothers. They ranged in age from 18 years-old to 50-years-old. At the time of her interview, each mother had at least one child who was three-years-old or younger. Through our discussions, we explored how pre-pregnancy perceptions, lived experiences as a mother, familial influences, and the discourses surrounding motherhood within an African-American context affected the perceptions and experiences that the mothers in the study had with their infant feeding practice(s). Findings suggest that while African Americans mothers know that “breast is best,” that knowledge is not the only reason for their decisions. The first step in understanding why African-American mothers choose the feeding method(s) that they choose is embracing the reality that choosing is an ongoing and dynamic process which is often informed by what she does versus “is supposed to do” versus how she is portrayed weighed with the consequences of her choice(s) for herself and her family. Further, African American mothers are in the active process of negotiating an evolving definition of themselves within this post-Civil Rights, Affirmative Action context wherein choices appear abundant, but the choosing always comes with a price.
Los estilos APA, Harvard, Vancouver, ISO, etc.
27

Nzeneri, Samuelson. "Modélisation des efflorescences de l'algue toxique(Alexandrium minutum) en compétition interspécifique en Rade de Brest, France". Thesis, Brest, 2019. http://www.theses.fr/2019BRES0113.

Texto completo
Resumen
Alexandrium minutum est un dinoflagellé toxique responsable de crises sanitaires et économiques. En France, cette espèce est observée depuis 1988. Cette étude tente de hiérarchiser les paramètres contrôlant le succès d'A. minutum au sein de la communauté phytoplanctonique par un suivi dans l’estuaire de Daoulas (Rade de Brest) et le développement d’un modèle 0D. Ce modèle basé sur des traits physiologiques met en compétition. A. minutum avec 72 autres espèces réparties de manière uniforme dans l'espace des traits. Les résultats montrent une variabilité saisonnière et inter-annuelle des efflorescences. D’avril à octobre se succèdent le micro puis le nano et enfin le picophytoplancton, contrôlés par la température et la lumière en hiver puis par le phosphore puis l'azote, durant l'été. Les blooms d'A. minutum apparaissent entre juin et août. Les résultats de la modélisation, corroborés par les données, ont montré une efflorescence tardive d’A. minutum lors d’un printemps froid (2013) et précoce lors d’un printemps chaud (2014). Le maximum d’abondance d’A. minutum est observé et simulé en 2012 où les forts débits durant l'été ont entrainé des apports en nutriments très élevés et la plus faible abondance en 2011, été le plus sec sur la période considérée. Le modèle a permis de tester l’impact de scénarios de réduction de 50% d’azote et de phosphore dans les apports. Seule une réduction de phosphore entraîne une diminution de l’abondance d’A. minutum, les apports de la rivière restant très riches en azote. Le modèle n'est toutefois pas consistant sur toute la période d'étude ce qui met en lumière l'importance probable d'autres facteurs dans la régulation des efflorescences
Alexandrium minutum is one of the toxic species that produce Harmful Algal Blooms (HABs), threaten public health, aquaculture and tourism. In France, it was observed in 1988 in the region Bretagne. High levels of Paralytic Shellfish Poisoning (PSP) toxicity have been detected in the estuaries of Morlaix, Penzé, Rance, Abers and more recently, in the Bay of Brest. This work tries to define and place in order of hierarchy, the parameters driving A. minutum success in the phytoplankton community. Two approaches were adopted. The first was a temporal survey at the study site since 2009-2018. The second was the use of a 0D numerical model (based on physiological traits) to simulate the potential impact between physical and biological processes. A. minutum was placed in competition with 72 species which were uniformly selected. Results showed both seasonal and interannual variability of bloom phenology. It was marked by micro, followed by nano and then pico phytoplankton from April to October. A. minutum bloom occurred between June and August, a period of high temperature, low nutrient concentrations and high resource competition. However, environmental factors and competition explain only a part of its phenology. Though the model was able to reproduce the seasonal and interannual variability of A. minutum, simulation was inconsistent over the study period. The model highlights the increasing relevance of other biological processes in bloom regulation at decade scale. It might improve some models which are able to correctly predict instances of A. minutum presence or absence. The perspective is to have a model which can be applied and validated for the entire Bay of Brest
Los estilos APA, Harvard, Vancouver, ISO, etc.
28

McIntosh, Gary Gordon. "Evaluation of the clinical and biological significance of overexpression of... genes at the int-2/hst-1 oncogene amplification locus on band q13 of chromosome 11 in human breast cancer". Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321591.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
29

Gregoire, Gwendoline. "Dynamique sédimentaire et évolution holocène d'un système macrotidal semi-fermé : l'exemple de la rade de Brest". Thesis, Brest, 2016. http://www.theses.fr/2016BRES0103/document.

Texto completo
Resumen
La rade de Brest constitue un cadre idéal pour étudier et restituer les transferts sédimentaires terre-mer dans un contexte de bassin côtier semi-fermé macrotidal. Dans cette perspective, deux axes majeurs, d’échelle temporelle différente, ont été développés avec pour objectifs (a) de caractériser le modèle sédimentaire et sa dynamique par charriage à l’actuelle, (b) de déterminer la mise en place des dépôts sédimentaires au cours de la dernière transgression marine.(a) L’analyse combinant une approche sédimentaire et analogique a permis de montrer le contrôle majeur des courants de marée sur la dynamique sédimentaire actuelle. La morphologie du littoral et des fonds marins renforcent l’intensité des courants tidaux qui facilite les échanges en sables coquilliers entre la rade interne et la mer d’Iroise. Le système est néanmoins en érosion et enregistre un déséquilibre en apports sédimentaires. Les sédiments fins sont remobilisés par les courants de flot et les actions anthropiques colmatant les secteurs peu profonds.(b) L’étude litho- et chronostratigraphique de la séquence sédimentaire, a mis en évidence le recul successif des processus estuariens lors de la dernière remontée du niveau marin (holocène). La morphologie héritée du substratum, combinée à la transgression marine, a fortement influencé l’architecture des dépôts, leur préservation et leurs variations lithologiques latérales et longitudinales. Après la stabilisation du niveau marin (3 000 BP), les variations climatiques (optimum climatique médiéval, et petit âge glaciaire) et les activités anthropiques impactent d’avantage la dynamique des particules en suspension.La rade a donc eu un impact différent sur le transfert des sédiments au cours de la remontée du niveau marin. Actuellement, elle acte comme un « piège à sédiment fin » et enregistre dans le même temps un déficit de stock sédimentaire grossier potentiellement remobilisable. Cette configuration favorise une érosion des parties les plus profondes du système
The bay of Brest is a tide-dominated, semi-enclosed coastal basin, which is connected with two rivers (Aulne and Elorn). Its jagged shoreline and seabed morphology constitute an ideal setting to understand sedimentary transfer at the land-sea interface. In this aim, this study is divided in two different time scale. The first (a) focuses on the present-day sedimentary bedload dynamic and the second (b) on the reconstruction of the Holocene infilling, during the last marine transgression. (a) A analyse combining a sedimentology approach and numerical has highlighted the major control of the tidal currents. Swells and rivers have a minor impact, because the inherited morphology accentuates and promotes tidal currents. There are responsible of a shelly sandy exchange between the oceanic domain (Iroise Sea) and confined (bay of Brest). At present, the bay of Brest suffers from an imbalance of shelly sand. Fine sediments are eroded and redistributed in the shallow parts of the bay. In ideal conditions (strong tidal current) they can be exported.(b) From the stratigraphic and chronostratigraphic analyses, the successive landward retreat of estuarine processes, during the last marine transgression, has been observed. The sea level acts as the major factor control of the sedimentary geometry deposits. However, the morphological particularity of the bay of Brest influenced their preservation and it is possible to determinate the longitudinal and transversal asymmetry. After the sea level stabilisation (3 000 BP), the Holocene climatic variations and anthropic activities have disturbed the suspension dynamic.The bay of Brest had a different impact on the sedimentary transfer during the last marine transgression. At present, it acts as a « sediment trap » for the fine particles and has not enough sandy sediment. This configuration tends to an erosion of the system
Los estilos APA, Harvard, Vancouver, ISO, etc.
30

Bao, Xuanwen [Verfasser], Michael J. [Akademischer Betreuer] Atkinson, Harry [Gutachter] Scherthan y Karima [Gutachter] Djabali. "Effects of cellular aging in human and murine MSCs on their DNA double-strand break repair and telomere stability / Xuanwen Bao ; Gutachter: Harry Scherthan, Karima Djabali ; Betreuer: Michael J. Atkinson". München : Universitätsbibliothek der TU München, 2020. http://d-nb.info/122031935X/34.

Texto completo
Los estilos APA, Harvard, Vancouver, ISO, etc.
31

Lacroix, Camille. "Impacts de perturbateurs environnementaux sur un organisme sentinelle des milieux côtiers anthropisés, la moule bleue Mytilus spp. : caractérisation génomique et écophysiologique de l'adaptation au stress". Thesis, Brest, 2014. http://www.theses.fr/2014BRES0120/document.

Texto completo
Resumen
Dans le contexte actuel de changement global et particulièrement de réchauffement climatique et de pollution chimique chronique, se pose la question de la vulnérabilité des écosystèmes côtiers et notamment des populations d’invertébrés filtreurs jouant un rôle structurant dans la plupart de ces écosystèmes. Dans ces travaux de thèse, une approche couplée d’écophysiologie et de génomique fonctionnelle a été mise à profit afin de mieux comprendre les processus moléculaire, cellulaire et physiologique de réponse à une contamination chimique chronique modérée et d’évaluer la capacité à faire face à une augmentation de température chez des populations naturelles de moules bleues (Mytilus spp.) de la Rade de Brest. Les résultats obtenus révèlent qu’une contamination chronique modérée induit des réponses adaptatives au niveau subcellulaire chez les moules exposées, prévenant ainsi l’apparition de souffrances physiologiques et permettant aux populations de se maintenir dans un environnement variable. Ces réponses impliquent en particulier, une activation des mécanismes de défense cellulaire (métabolisme énergétique et défenses antioxydantes) et d’élimination des xénobiotiques. Par ailleurs, l’exposition à une augmentation de température en conditions expérimentales ne met pas en évidence de sensibilité particulière au stress thermique chez les moules provenant d’un site exposé à une contamination chronique modérée. En revanche, les résultats indiquent que ces dernières pourraient avoir une plus grande capacité à compenser grâce à des réponses adaptatives, les effets délétères générés par une augmentation de température. Cependant, le fort coût énergétique généré par la contamination chimique ainsi que les effets importants du stress thermique mis en évidence dans ces travaux indiquent que la combinaison de ces deux sources de stress pourrait provoquer des dysfonctionnements métaboliques et représenter à l’avenir, une menace pour les populations naturelles de moules bleues. Ces travaux de thèse ont également contribué au développement de nouvelles méthodologies permettant respectivement, de quantifier des contaminants environnementaux dans des tissus biologiques marins, d’étudier des réponses génomiques précoces de stress et de mesurer des paramètres physico-chimiques in situ. Ces méthodologies pourront contribuer à améliorer les performances du diagnostic de l’état de santé des populations naturelles de moules et au delà, d’espèces-sentinelles de mollusques bivalves dans un contexte de contamination chimique mais également de changements climatiques
In the current context of chronic chemical pollution and on-going climate change, coastal ecosystems, and in particular keystone filter-feeding bivalve populations inhabiting them, appear vulnerable. In this thesis, an approach coupling ecophysiology and functional genomics was used to study the molecular, cellular and physiological responses of wild blue mussel populations of the Bay of Brest to a moderate chronic chemical contamination, and to assess the ability of these populations to face a heat stress. Results indicate a moderate chronic chemical contamination induces adaptive responses in wild mussel populations from the Brest harbour area, which prevents severe physiological disturbances and sustain long-term population survival. These responses include an activation of cellular stress response [energetic metabolism and antioxidant defences) and xenobiotic elimination mechanisms. Furthermore, experimental heat stress exposure does not highlight a higher sensitivity to a temperature increase in mussels sampled in a moderately contaminated area but suggests that these mussels could have a better ability to offset the adverse effects of heat stress thanks to adaptive responses. However, the high energetic cost of chemical contamination and the strong effects of heat stress presented in this work, suggest combined chemical and heat stress could be a future threat for wild blue mussel populations. This work also contributes to the development of new methodologies to, respectively, quantify environmental contaminants in marine biota, study early warning genomic stress responses and to survey physicochemical parameters in situ. These methodologies contribute to improving the health diagnostics of natural mussel populations and thus, appear as useful tools to assess health of bivalve sentinel species populations in biomonitoring studies, in a context of chemical contamination and climate change
Los estilos APA, Harvard, Vancouver, ISO, etc.
32

Wu, Man-Mei. "Three Voices for voices, woodwind, percussion, and string instruments". Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2684/.

Texto completo
Resumen
Composed for soprano, tenor, and baritone voices, woodwind, percussion, and string instruments, Three Voices is a polyglotic work that includes German, Chinese, and Spanish texts. The texts are chosen from Brecht Bertolt's Das Schiff, Po Chu I's Lang T'ao Sha, and Frederico Garcia Lorcá's Mar. Significant features of the piece are 1) application of Chinese operatic singing methods to vocal material in the sections that use Chinese text, 2) use of western instruments to emulate the sound of certain Chinese instruments, and 3) employment of Sprechstimme and dramatically inflected speech to create theatrical effects and highlight the sections that use German and Spanish texts.
Los estilos APA, Harvard, Vancouver, ISO, etc.
33

Paixão, Thiago Regis Longo Cesar da. "Utilização de eletrodos de Cu e Au em eletroanalítica: detecção amperométrica de etanol em ar exalado e outras aplicações". Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-14062007-160003/.

Texto completo
Resumen
A potencialidade do eletrodo de cobre em meio alcalino foi demonstrada para o determinação de etanol a +0,6 V vs Ag/AgCl. A participação de espécies solúveis de Cu(III) no processo eletrocatalítico envolvendo a oxidação do etanol foi demonstrada por experimentos utilizando eletrodo disco-anel. A influência do potencial de pré-tratamento no sinal anódico foi investigada e correlacionada com a morfologia dos filmes formados na superfície do eletrodo por EDS (Energy Dispersive X-Ray Spectroscopy), indicando que as espécies de Cu(III) são originadas a partir da oxidação da camada de CuO. As medidas de etanol foram realizadas por amperometria em 0,6 V (vs Ag/AgCl). A repetibilidade das medidas utilizando padrão aquoso de etanol 0,05 % (v/v) foi de 3 % (v/v) e os limites de detecção e quantificação foram de 0,005 % (v/v) e 0,01 % (v/v), respectivamente. Nas condições experimentais otimizadas, o sensor amperométrico foi utilizado para o monitoramento da concentração de etanol no ar exalado (BrAC), que foi convenientemente coletado em um balão de borracha (V = 3 L) e introduzido em uma solução de NaOH 1 mol L-1 (V = 10 mL). O sensor apresentou uma faixa linear para concentrações de etanol em ar exalado na faixa de 0,26 – 130 mg L-1, operando de acordo com os parâmetros analíticos especificados na Legislação Brasileira para a quantificação de etanol no ar exalado em condutores de veículos automotores. A constante de eliminação de etanol do corpo humano também foi investigada e os resultados concordaram com os valores da literatura. Empregando-se eletrodos de Cu e Au foram também desenvolvidas outras metodologias para a quantificação de dipirona, glicose e ácido ascórbico e sistemas em fluxo. Estudos sobre o desenvolvimento e propriedades de um sistema gerador-coletor foram realizados e o dispositivo foi utilizado em titulações de substâncias redutoras com iodo gerado eletroquimicamente.
A copper disc working electrode in alkaline solutions was demonstrated to act as a suitable amperometric sensor for ethanol determination at +0.6 V vs Ag/AgCl. The participation of free-soluble Cu(III) species in the electrocatalytic process involving the anodic oxidation of ethanol has been demonstrated by rotating ring-disc electrode voltammetry. The influence of the pretreatment potential on the anodic signal was investigated and a correlation with the morphology of the electrode surface characterized by Energy Dispersive X-Ray Spectroscopy (EDS) indicated that the Cu(III) species is originated from the oxidation of a CuO layer. Ethanol measurements were performed in the amperometric mode at 0.6 V (vs Ag/AgCl). The repeatability of the measurements for a 0.05 % aqueous ethanol solution was estimated as 3 %, and the detection and quantification limits were determined as 0.005 % and 0.01 %, respectively. At the optimum experimental conditions, the amperometric sensor was used to monitor the concentration of ethanol in breath (BrAC), which was conveniently collected in a rubber air balloon (volume = 3 L) and introduced in a 1 mol L-1 NaOH working solution (volume = 10 mL). The sensor can measure a person\'s breath ethanol over the concentration range 0.26 - 130 mg L-1 by operating it according to an established protocol, of which the analytical parameters are specified by the Brazilian Legislation for BrAC measurements in drivers. The rate of ethanol degradation in the body was followed, and the results agree with predictions in the literature. Methodologies for the determination of dipyrone, glucose and ascorbic acid were also developed by using Cu and Au electrodes. Features of a dual-band electrochemical cell were investigated towards the development of a generator-collector system, which was employed in titrations with electrogenerated iodine.
Los estilos APA, Harvard, Vancouver, ISO, etc.
34

Drui, Florence. "Modélisation et simulation Eulériennes des écoulements diphasiques à phases séparées et dispersées : développement d’une modélisation unifiée et de méthodes numériques adaptées au calcul massivement parallèle". Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLC033/document.

Texto completo
Resumen
Dans un contexte industriel, l’utilisation de modèles diphasiques d’ordre réduit est nécessaire pour pouvoir effectuer des simulations numériques prédictives d’injection de combustible liquide dans les chambres de combustion automobiles et aéronautiques, afin de concevoir des équipements plus performants et moins polluants. Le processus d’atomisation du combustible, depuis sa sortie de l’injecteur sous un régime de phases séparées, jusqu’au brouillard de gouttelettes dispersées, est l’un des facteurs clés d’une combustion de bonne qualité. Aujourd’hui cependant, la prise en compte de toutes les échelles physiques impliquées dans ce processus nécessite une avancée majeure en termes de modélisation, de méthodes numériques et de calcul haute performance (HPC). Ces trois aspects sont abordés dans cette thèse. Premièrement, des modèles de mélange, dérivés par le principe variationnel de Hamilton et le second principe de la thermodynamique sont étudiés. Ils sont alors enrichis afin de pouvoir décrire des pulsations des interfaces au niveau de la sous-échelle. Des comparaisons avec des données expérimentales dans un contexte de milieux à bulles permettent de vérifier la cohérence physique des modèles et de valider la méthodologie. Deuxièmement, une stratégie de discrétisation est développée, basée sur une séparation d’opérateur, permettant la résolution indépendante de la partie convective des systèmes à l’aide de solveurs de Riemann approchés standards et les termes sources à l’aide d’intégrateurs d’équations différentielles ordinaires. Ces différentes méthodes répondent aux particularités des systèmes diphasiques compressibles, ainsi qu’au choix de l’utilisation de maillages adaptatifs (AMR). Pour ces derniers, une stratégie spécifique est développée : il s’agit du choix de critères de raffinement et de la projection de la solution d’une grille à une autre (plus fine ou plus grossière). Enfin, l’utilisation de l’AMR dans un cadre HPC est rendue possible grâce à la bibliothèque AMR p4est, laquelle a montré une excellente scalabilité jusqu’à plusieurs milliers de coeurs de calcul. Un code applicatif, CanoP, a été développé et permet de simuler des écoulements fluides avec des méthodes de volumes finis sur des maillages AMR. CanoP pourra être utilisé pour des futures simulations d’atomisation liquide
In an industrial context, reduced-order two-phase models are used in predictive simulations of the liquid fuel injection in combustion chambers and help designing more efficient and less polluting devices. The combustion quality strongly depends on the atomization process, starting from the separated phase flow at the exit of the nozzle down to the cloud of fuel droplets characterized by a disperse-phase flow. Today, simulating all the physical scales involved in this process requires a major breakthrough in terms of modeling, numerical methods and high performance computing (HPC). These three aspects are addressed in this thesis. First, we are interested in mixture models, derived through Hamilton’s variational principle and the second principle of thermodynamics. We enrich these models, so that they can describe sub-scale pulsations mechanisms. Comparisons with experimental data in a context of bubbly flows enables to assess the models and the methodology. Based on a geometrical study of the interface evolution, new tracks are then proposed for further enriching the mixture models using the same methodology. Second, we propose a numerical strategy based on finite volume methods composed of an operator splitting strategy, approximate Riemann solvers for the resolution of the convective part and specific ODE solvers for the source terms. These methods have been adapted so as to handle several difficulties related to two-phase flows, like the large acoustic impedance ratio, the stiffness of the source terms and low-Mach issues. Moreover, a cell-based Adaptive Mesh Refinement (AMR) strategy is considered. This involves to develop refinement criteria, the setting of the solution values on the new grids and to adapt the standard methods for regular structured grids to non-conforming grids. Finally, the scalability of this AMR tool relies on the p4est AMR library, that shows excellent scalability on several thousands cores. A code named CanoP has been developed and enables to solve fluid dynamics equations on AMR grids. We show that CanoP can be used for future simulations of the liquid atomization
Los estilos APA, Harvard, Vancouver, ISO, etc.
35

Ftiti, Zied. "Politique de ciblage d’inflation : règles de conduites, efficacité, performance". Thesis, Lyon 2, 2010. http://www.theses.fr/2010LYO22005/document.

Texto completo
Resumen
Depuis 1990, bon nombres de pays industrialisés et émergents ont adopté la politique de ciblage d’inflation. Ce régime monétaire a été adopté sans théorie adjacente dans la mesure où il a démarré comme une solution alternative à la recherche sans fin d’un système d’ancrage nominal suite aux échecs répétés des politiques antérieurs. Ce retard théorique fait naître de nombreux débats économiques sur la conduite de ce régime monétaire dont les plus importants feront l’objet d’une discussion approfondie au sein de cette thèse. Dans un premier chapitre, nous définissons la politique de ciblage d’inflation. Dans un second chapitre nous abordons la question de la conduite optimale de ce régime d’un point de vue théorique et empirique. Nous montrons que la règle optimale est une règle à la Taylor de type Forward-Looking dont elle peut avoir un comportement asymétrique. Dans un troisième chapitre, nous abordons la question de l’efficacité de la politique de ciblage d’inflation. Pour ce faire, nous avons étudié l’effet d’intervention de ce régime sur la dynamique d’inflation. Nous avons recours à la théorie spectrale évolutive afin de modéliser la série de l’inflation dans le but de tester son évolution. Les résultats sont en faveur de l’efficacité de ciblage d’inflation. Le dernier axe de cette thèse s’intéresse à la question de la performance économique de ce régime monétaire. Pour ce faire nous développons une méthodologie originale évaluée selon une approche économétrique originale. En effet, nous qualifions le ciblage d’inflation comme économiquement performant s’il génère une stabilité de l’environnement de la politique monétaire. Le fondement de cette idée fera l’objet du quatrième chapitre. Quant au chapitre cinq, il développera l’approche économétrique basée sur la théorie co-spectrale pour mesure le degré de stabilité de cet environnement. Les résultats montrent que le ciblage d’inflation est économiquement performant
The inflation targeting policy (ITP) was born after the failure of many monetary policies. However, the ITP was adopted without inherent theory which raised many discussions. In this dissertation, we study the most important debates. In the first chapter, we defined the ITP. Then, we treat the question of the optimal rule conduct. We show that the optimal monetary rule is a type Taylor rule under a Forward-Looking version and which can be linear or nonlinear. In the third chapter, we focus on the discussion about the relevance of the inflation targeting policy. To study this point we use the evolutionary spectral analysis to model the inflation series and we test then, if the ITP cause a structural break. Our results show the relevance of the ITP. The last discussion in this work is to check the macroeconomic performance of the ITP. The main idea is to consider the ITP as economically efficient when it generates a stable monetary environment. The latter is considered as stable when a long-run equilibrium exists to which the paths of economic variables (inflation rate, interest rate and GDP growth) converge. The convergence of the variables’ paths implies that these variables are more predictable and implies a less uncertainty in the economic environment. To measure the degree of convergence between economic variables, we propose, in this paper, a dynamic time-varying variable presented in the frequency approach named cohesion. This variable is estimated from the evolutionary co-spectral theory. The results show that the ITP is a relevance policy and generate a good performance
Los estilos APA, Harvard, Vancouver, ISO, etc.
36

Randeree, Aziza Muhammed. "The efficacy of homoeopathic simillimum treatment of oral malodour". Thesis, 1999. http://hdl.handle.net/10321/2850.

Texto completo
Resumen
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Homoeopathy, Technikon Natal, 1999.
The purpose of this placebo-controlled study was to evaluate the efficacy of the homoeopathic simillimum treatment in halitosis in terms of the volatile sulphur compounds being measured objectively by the portable sulphide monitor and subjectively by organoleptic measurement\x87
M
Los estilos APA, Harvard, Vancouver, ISO, etc.
37

Félix, Rita Isabel Amaro de Sousa. "Instituto do hálito negócio inovador na área da medicina dentária: o tratamento da halitose". Master's thesis, 2012. http://hdl.handle.net/10071/6129.

Texto completo
Resumen
O problema do mau-hálito (ou halitose) é geralmente associado a questões de imagem pessoal, constituindo por isso fonte de preocupação, sobretudo junto das pessoas de classes mais elevadas e/ou pessoas mais expostas ao contacto com outros. É esta a razão pela qual existem inúmeros produtos que promovem a sua resolução, embora na maioria das vezes seja apenas um disfarce do problema. Contudo, provavelmente não é do conhecimento do público em geral é que ter mau-hálito pode não ser a causa, mas antes a consequência de outro tipo de problemas, os quais apenas um profissional com qualificação multi-disciplinar poderá ter a competência e conhecimentos para decifrar. O presente projecto pretende, no âmbito do marketing de saúde e social, informar e alertar não só a população geral, mas em especial os profissionais de saúde sobre o tema. Em segundo lugar, este projecto destina-se também a criar condições para a implementação em Portugal de um negócio para tratamento da halitose. Palavras chave: mau-hálito, marketing na saúde, marketing social, plano de negócio na área da saúde.
The problem of bad breath (or halitosys) is usually associated to personal image issues, which makes it a source of concern, specially for persons of a higher social class and/or persons who are more exposed in their contact to others. This is the reason why there are so many products who promote their resolution, although most of the time is only a disguise of the problem. However, the point not so well know is that having bad breath is not the cause, but the consequence of other type of problems, that only a multi-disciplinar qualified professional may have the competence to decode. The present project pretends, in the scope of the social and health marketing, to inform and alert not only the general population, but in special the health professionals. In second, this project aims also to create the conditions for the implementation in Portugal, of a business for the treatment of the halitosys. Keywords: bad breath, heatlh marketing, social marketing, healthcare business plan.
Los estilos APA, Harvard, Vancouver, ISO, etc.
38

Ferreira, Joana Filipa Azevedo. "Halitose: da etiologia ao tratamento". Master's thesis, 2016. http://hdl.handle.net/10284/5604.

Texto completo
Resumen
A halitose é uma condição ou alteração do hálito, sendo caracterizada por um hálito desagradável emitido pela expiração. Segundo a Organização Mundial de Saúde (OMS), é considerado um problema de saúde, visto que afeta cerca de 40% da população mundial. Este problema causa desconforto e constrangimento social, sendo assim um limitador da qualidade de vida e da autoestima de quem a padece. Atualmente sabe-se que a halitose pode ser caracterizada como verdadeira, pseudo-halitose ou halitofobia. A halitose verdadeira pode ser uma halitose patológica ou fisiológica. A sua etiologia é multifatorial e o seu tratamento é multidisciplinar. Por outro lado, tanto a pseudo-halitose como a halitofobia provêm do foro psicológico, sendo necessário a ajuda de um psicólogo ou psiquiatra. Existem vários testes de diagnóstico (halímetro, cromatografia gasosa, BANA, entre outros) para avaliar a presença e a severidade desta patologia. O tratamento desta patologia consiste na eliminação das cáries e doenças periodontais, dando instruções de higiene oral para reforçar a escovagem dentária, o uso do fio dentário e a higiene das próteses. O aconselhamento dietético e a limpeza da língua também são essenciais, como também o controlo do biofilme com anti-séticos orais (Abreu et alii., 2011; Machado et alii., 2008). O objetivo desta revisão bibliográfica assenta na determinação de diversas possibilidades de prevenção e tratamento bem como a sua eficácia, sendo esta fundamental para o reconhecimento e correta interpretação da halitose. A pesquisa bibliográfica sobre o tema “Halitose: da etiologia ao tratamento” foi realizada essencialmente em motores de busca como o Pubmed e a Scielo, em três idiomas, Português, Inglês e Espanhol. selecionando artigos na sua maioria entre os anos 2006-2016. O médico médico dentista tem como função, na maioria dos casos, de tratar esta patologia ou então, quando não está associada à cavidade oral, reencaminhar o paciente para a especialidade médica adequada. Contudo, é de salientar que o paciente também possui um papel ativo no tratamento e na manutenção da halitose.
Halitosis is a condition or change of breath and it is characterized by a bad breath issued by expiration. According to the World Health Organization (WHO), it is considered a health problem that affects about 40% of world population. This problem causes discomfort and social embarrassment , therefore a limiting quality of life and self esteem of those who suffer. Nowadays, it is known that halitosis can be characterized as true or pseudohalitosis or halitophobia. The real halitosis can be a physiological or pathological halitosis. Its etiology is multifactorial, being the treatment multidisciplinary. Moreover, the pseudo-halitosis and halitophobia have psychological conditions, requiring the help of a psychologist or psychiatrist. There are several diagnostic tests (halimeter , gas chromatography, BANA , and others) to assess the presence and severity of this disease. The treatment of this pathology consists in the tooth decay removal as well as the periodontal disease. Additionally, instruction oral hygiene can be given such as the increase the tooth brushing, the use of dental flossing and dental prosthesis. Dietary advices and tongue cleaning are also essential, as well as the control of biofilms with oral anti-septics. The purpose of this literature review consist to understand halitosis prevention and treatment as well as its effectiveness. Being this approach of great importance, to detect and for the correct interpretation of halitosis. The bibliographic research for the theme "Halitosis : from etiology to treatment" essentially performed in Pubmed and Scielo. Selecting articles mostly between the years 2006-2016, in three languages Portuguese , English and Spanish. In most cases, this pathology is treated by dentist or by a medical specialist when not associated with the oral cavity. However, it is well known the importance of the patient´s active role in the treatment and control of halitosis.
Los estilos APA, Harvard, Vancouver, ISO, etc.
39

Fernando, Romaine Ingrid. "BAD is a central player in cell death and cell cycle regulation in breast cancer cells". 2004. http://etd.utk.edu/2004/FernandoRomaine.pdf.

Texto completo
Resumen
Thesis (Ph. D.)--University of Tennessee, Knoxville, 2004.
Title from title page screen (viewed Feb. 16, 2005). Thesis advisor: Jay Wimalasena. Document formatted into pages (xii, 145 p. : ill. (some col.)). Vita. Includes bibliographical references (p. 120-144).
Los estilos APA, Harvard, Vancouver, ISO, etc.
40

LO, WEN-TING y 羅文婷. "Application of Kano Model to explore insulation bag for breast milk". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/6898tm.

Texto completo
Resumen
碩士
亞洲大學
創意商品設計學系
105
With the social structure change, the number of career woman gradually increases, and policies encourage mothers to breastfeed. Career woman choose to breast-feeding, you will encounter the collection, storage, carrying and other problem. Insulation bag for breast milk, which are divided into the following two types for "general use" and "breast milk special". Generally used can’t be applied to career woman of collect breast milk; Breast milk special is designed for the collection of breast milk equipment design, after breastfeeding stage, limited by size, can’t easily change the use and reduce product life cycle. This study uses the depth of interviews, Kano Model quality evaluation to find the basic needs of Insulation bag for breast milk and charm factors, the design of the next generation of insulation bag for breast milk design. This study applies in-depth interviews, Kano Model quality evaluation to find the basic needs and charm factors of insulation bag for breast milk. Career women were invited to in-depth interview about the using experience of insulation bag for breast milk in this study. From the use of experience pleasure and unpleasant vocabulary corresponds to the product components of the insulation bag, apply to the Kano Model questionnaire. Based on the analysis results, we design the next generation of insulation bag for breast milk. According to Kano Model questionnaire and consumer satifaction find the charm factor of insulation bag for breast milk. As a result, the design elements that affect this product is place the breast pump and breast milk collection bags, folding function, strap can be disassembled, divided external space, external space more than two. The second generation design of breast milk bag style is follow the above elements. The internal of cubic insulation bag is a single space. In order to provide extra storage space for external of insulation bag, the insulation bag was separated into two part, internal and external part. Meanwhile, the side strap is able to add or remove under the demand. The flexible insulation bag improve the satisfaction of customers and extend life cycle of products to meet the friendly environmental goal.
Los estilos APA, Harvard, Vancouver, ISO, etc.
41

Saif, Zarqa. "Functional analysis of CBFA2T3: a breast cancer tumour suppressor from chromosome band 16q24.3". 2009. http://hdl.handle.net/2440/58023.

Texto completo
Resumen
Loss of heterozygosity (LOH) of 16q is an early event occurring in 36-60% of primary sporadic breast cancers. CBFA2T3 (MTG16) is a putative breast cancer tumour suppressor gene, localized at chromosome band 16q24.3. CBFA2T3 (MTG16) belongs to the CBFA2T protein family and shares a high homology with other two members, CBFA2T1 (MTG8) and CBFA2T2 (MTGR1). CBFA2T1 and CBFA2T3 proteins form transcriptional repressor complexes with the DNA binding zinc finger proteins like BCL6, PLZF, Gfi1 and ZNF652. CBFA2T3 protein exists as isoform “a” and “b” that arise from alternate start sites. These isoform differ in their N-terminal sequences. Previous studies determined that CBFA2T3a localized to the nucleolus, while CBFA2T3b has a putative role as tumour suppressor protein. The present study confirms that the database entries of CBFA2T3a are incomplete and an extended N-terminus region is present to CBFA2T3a (NCBI NM_005187) isoform by RTPCR and DNA sequencing. Two rabbit polyclonal anti CBFA2T3 antibodies were raised against the region unique to CBFA2T3. These antibodies specifically detect the endogenous CBFA2T3 proteins and not CBFA2T1 and CBFA2T2. Cell fractionation studies show that endogenous CBFA2T3a localized to the cytoplasm, while CBFA2T3b targeted to the nucleus. The N-terminus region specific to “a” isoform determined the cytoplasmic localization. The detailed studies show that CBFA2T3a localized to centrosome and this was confirmed by co–localization with known centrosomal proteins γ- tubulin. This was further confirmed by immunoprecipitation of γ-tubulin with N-terminus regions of CBFA2T3a protein. Further investigation showed that CBFA2T3a localizes to the centrosome through out the centrosomal duplication. Presence of CBFA2T3a on procentriole was further confirmed by co-localization with known proteins having a crucial role in centrosome duplication like HsSAS6 and polyglutamilated tubulin. Experiments were conducted to determined if the different subcellular localization of “a” and “b” isoforms resulted into functional differences between two isoforms. Immunoprecipitation experiments with known DNA binding proteins like BCL6 and PLZF showed that CBFA2T3b interacts with BCL6, while no interaction was found with PLZF. Consistent with the known transcriptional co-repressor function, real time RT-PCR showed that CBFA2T3b has an additive effect on BCL6 mediated repression of its target cyclin D2, while no effect was observed with CBFA2T3a. Real time RT-PCR data also showed that BCL6 not only recruits CBFA2T3b to repress its target but also have repressive effects on CBFA2T3 transcription. CBFA2T3b transcription regulation by BCL6 was found to be mediated through one or two BCL6 putative binding sites in CBFA2T3b promoter. Immuno histochemical studies were carried out to analyse CBFA2T3b function as a breast cancer tumour suppressor. CBFA2T3 proteins are highly expressed in epithelial cell lineage of normal breast ducts, while its expression is lost in some tumours. CBFA2T3 expression was further analysed in a cohort of commercially available breast tumour sections. Data from these studies showed the loss of CBFA2T3 nuclear expression in some tumours, which was significantly correlated with tumours positive for HER2 expression, molecular subtypes and histological staging of the tumours. CBFA2T3 cytoplasmic expression was also down regulated in tumour sections. A significant association of CBFA2T3 cytoplasmic expression was observed with the TNM grading for tumour invasion and centrosomal abnormalities in BR701 TMA. Knock down studies using shRNA were conducted to investigate the role of CBFA2T3a. Following CBFA2T3 knock down in cells with minimal CBFA2T3b expression, an increase in centrosomal abnormalities was observed. These abnormalities were associated with a significant increase in metaphase anomalies. Since the “a” isoform is localized to cytoplasm and particularly centrosome, it was considered that this isoform is determining centrosome integrity. This work has provided a new insight into the localization pattern of CBFA2T3 isoforms, as CBFA2T3a and b isoforms were localized to different cellular compartments and were involved in distinct functions. CBFA2T3b function as a transcriptional co repressor, CBFA2T3b expression was lost in a group of breast tumours sections. Given that CBFA2T3a has a critical centrosomal function, the expression of this isoform would be expected to be maintained, even in the absence of the CBFA2T3b isoform in tumours. CBFA2T3a specific knock down studies may give a full insight on direct targets of CBFA2T3a, having a controlling role in normal centrosome duplication cycle.
http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1474414
Los estilos APA, Harvard, Vancouver, ISO, etc.
42

Silva, Maria Virgolino e. "Relatórios de Estágio e Monografia intitulada “Oxysterols and their effects: The good, the bad and the not so ugly”". Master's thesis, 2017. http://hdl.handle.net/10316/83744.

Texto completo
Resumen
Relatório de Estágio do Mestrado Integrado em Ciências Farmacêuticas apresentado à Faculdade de Farmácia
Oxysterols, oxygenated derivatives of cholesterol, are compounds with 27 structuralcarbons, substituted with polar groups as hydroxyl, keto, hydroperoxy, epoxy or carboxyl atrings A and B as well on the side chain. These compounds are either produced by reactiveoxygen species or by enzymatic reactions. The route of synthesis has influence on thebiological effects of oxysterols, since compounds oxidized on rings A or/and B are implicatedin toxic effects and the ones oxidized in the lateral chain are implicated in importantbiological roles influencing specific targets. Oxysterols are not cholesterol end-productssince they exert metabolic activity on their own.The role of oxysterols is discussed in atherosclerosis and in breast cancer, being highlightedas promoters of breast cancer (27-hydroxycholesterol) and as anticancer compounds (5,6-epoxycholesterol and the sulphated derivative and dendrogenin A).The influence of Liver-X-Receptor is also established, since this nuclear receptor acts as apawn in atherosclerosis and in cancer development, being influenced by the binding ofagonists like oxysterols. Most oxysterols display antiproliferative properties in contrast with27-hydroxycholesterol which is a pro-proliferative agent. This activity is debated in thepresent document.The present work has the purpose to establish the role of oxysterols in differentperspectives, as “good”, “bad” and “not so ugly” compounds, since besides having a negativerole in cancer, oxysterols also have anticancer properties and have physiological propertiesas in the regulation of cholesterol metabolism.
Os oxiesteróis, derivados oxigenados do colesterol, são compostos com 27 carbonosestruturais substituídos por grupos polares como grupos hidroxilo, cetonas, hidroxiperóxi,epóxi ou carboxilo nos anéis A e B como também nas cadeias laterais. Estes compostospodem ser produzidos através de reações não enzimáticas, por espécies reativas de oxigénioou por reações enzimáticas. A via de síntese tem influência nos efeitos biológicos dosoxiesteróis, uma vez que oxiesteróis oxidados nos anéis A e B têm efeitos tóxicos, enquantoque os que são oxidados nas cadeias laterais estão implicados em processos biológicosinfluenciando alvos específicos. Os oxiesteróis não são produtos finais do colesterol, umavez que apresentam atividade metabólica própria.O papel dos oxiesteróis é discutido sob o ponto de vista da aterosclerose e do cancro damama, sendo destacado o seu efeito como promotores do cancro da mama (27-hidroxicolesterol) e como moléculas protetoras do desenvolvimento de cancro (5,6-epoxicolesterol e seu derivado sulfatado e dendrogenina A).A influência do Liver-X-Receptor é retratada, uma vez que este recetor nuclear atua como umpeão no desenvolvimento da aterosclerose e do cancro, sendo influenciado por agonistascomo os oxiesteróis. A maior parte dos oxiesteróis tem atividade anti-proliferativa quandose liga ao recetor, no entanto o 27-hidroxicolesterol apresenta a curiosa atividadeproliferativa que é debatida no presente documento.O presente trabalho tem por objetivo estabelecer o papel dos oxiesteróis de acordo comdiferentes perspetivas, compostos “bons”, “maus” e “não tão feios”, pois para além de teremum efeito negativo no cancro, também apresentam propriedades anticancerígenas epropriedades fisiológicas como a regulação do metabolismo do colesterol.
Los estilos APA, Harvard, Vancouver, ISO, etc.
43

Li, Chen-Yu y 李鎮宇. "Application of Blind Source Separation Algorithms on Dual-band IR Spectrogram for Breast Cancer Detection". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/06284823696915431885.

Texto completo
Resumen
碩士
國立臺灣大學
電子工程學研究所
104
This work presents an application of Blind Source Separation (BSS) Algorithms on Dual-band IR Spectrogram for breast cancer detection, which is used to trace the effect of long-term chemotherapy for breast-cancer patients. We take Dual-band IR Spectrogram’s RAW Data as an input to the BSS algorithms. Also, we plan to integrate this analytical algorithm into the back-end processor of our designed Dual-band IR Sensor and Readout Circuit Platform. This work will provide a more convenient medical application of our Improved Neighbor-based BSS algorithm on Dual-band IR Spectrogram for breast cancer detection. For Demarcating Degree, our Improved Neighbor-based BSS algorithm is approximately 15% better than other algorithms. For Correctness Rate, our improved algorithm approximately increases 10% compared with other algorithms.
Los estilos APA, Harvard, Vancouver, ISO, etc.
44

Puvanakrishnan, Priyaveena. "Near-infrared narrowband imaging of tumors using gold nanoparticles". 2011. http://hdl.handle.net/2152/14362.

Texto completo
Resumen
A significant challenge in the surgical resection of tumors is accurate identification of tumor margins. Current methods for margin detection are time-intensive and often result in incomplete tumor excision and recurrence of disease. The objective of this project was to develop a near-infrared narrowband imaging (NIR NBI) system to image tumor and its margins in real-time during surgery utilizing the contrast provided by gold nanoparticles (GNPs). NIR NBI images narrow wavelength bands to enhance contrast from plasmonic particles in a widefield, portable and non-contact device that is clinically compatible for real-time tumor margin demarcation. GNPs have recently gained significant traction as nanovectors for combined imaging and photothermal therapy of tumors. Delivered systemically, GNPs preferentially accumulate at the tumor site via the enhanced permeability and retention effect, and when irradiated with NIR light, produce sufficient heat to treat tumor tissue. The NIR NBI system consists of 1) two LED's: green (530 nm) and NIR (780 nm) LED for illuminating the blood vessels and GNP, respectively, 2) a filter wheel for wavelength selection, and 3) a CCD to collect reflected light from the sample. The NIR NBI system acquires and processes images at a rate of at least 6 frames per second. We have developed custom control software with a graphical user interface that handles both image acquisition and processing/display in real-time. We used mice with a subcutaneous tumor xenograft model that received intravenous administration and topical administration of gold nanoshells and gold nanorods. We determined the GNP's distribution and accumulation pattern within tumors using NIR NBI. Ex vivo NIR NBI of tumor xenografts accumulated with GNPs delivered systemically, demonstrated a highly heterogeneous distribution of GNP within the tumor with higher accumulation at the cortex. GNPs were observed in unique patterns surrounding the perivascular region. The GNPs clearly defined the tumor while surrounding normal tissue did not indicate the presence of particles. In addition, we present results from NBI of tumors that received topical delivery of conjugated GNPs. We determined that tumor labeling using topical delivery approach resulted in a more homogenous distribution of GNPs compared to the systemic delivery approach. Finally, we present results from the on-going in vivo tumor margin imaging studies using NIR NBI. Our results demonstrate the feasibility of NIR NBI in demarcating tumor margins during surgical resection and potentially guiding photo-thermal ablation of tumors.
text
Los estilos APA, Harvard, Vancouver, ISO, etc.
45

Chen-IanMing y 陳彥名. "Use of Small Break-off Test for Prediction of Concrete Strength and Evaluation of Adhesive Strength between Steel Bar and Concrete". Thesis, 2001. http://ndltd.ncl.edu.tw/handle/24765825062456526682.

Texto completo
Resumen
碩士
國立中興大學
土木工程學系
89
Abstract The objective of the thesis is to perform feasibility study of using a newly developed nondestructive technique called small break-off test for prediction of concrete strength and evaluation of adhesive strength between steel bar and concrete. In addition, the relationship of compressive strength between tiny cores and conventional cores is investigated Twelve specimens are constructed using three different mixtures of concrete associated with 490, 350, and 280kg/cm2. Ribbed and round steel bar with three different sizes of ＃7,＃8,and ＃10 are placed in the concrete specimens . Experimental results show that the break-off number has a good correlation with the adhesive strength. between steel bar and concrete. In addition, the break-off number is proportional to the strength of tiny cores.
Los estilos APA, Harvard, Vancouver, ISO, etc.
46

Wang, Yi-wen y 王意雯. "The study of the processing of sourdough bread using the culture of natural microorganisms from fruit fermented liquid (I): refrigerated starter in bag method". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/37251254841320854261.

Texto completo
Resumen
碩士
中興大學
食品暨應用生物科技學系
95
Sourdough is the dough containing natural LAB and yeast. Several products made from sourdough which are naturally fermented including the Chinese steamed bread and dumplings made in traditional ways and rye and wheat sourdough bread in the West. The distinguished taste, bigger size, extension of shelf life and higher nutrient facts feature the natural sourdough bread which is made from sourdough. However, developing the natural sourdough bread is complicated and it is hard to control the quality of bread because of its longer fermented time and complicated process. In this study two kinds of fruit, peach and grape, and two methods, refrigerated starter in bag method and continuous liquid starter method, are used to ferment sourdough bread. In the experiment of refrigerated starter in bag method peach is the major fruit to develop natural microorganisims and the sourdough starter is fermented in a bag at 10 ℃. After the natural microorganisms growing in the fermented liquid, two kinds of whole wheat flour are added to develop starter. Next, strong flour and water are both added into starter to make a dough style starter. Then, the dough style starter have been placed in a bag at 10 ℃ for 0, 5, 7 and 9 days before they are made into sourdough bread. Microorganisms like LAB and yeast, chemical quality factors like pH, TTA and sugar and components like soluble sugar, organic acid and alcohol are all investigated to know their immediate changes during fermentation processes. Through this investigation, two matters are understood including the meaning of every step in the process of bread making and how important a part each step plays in the process. Simultaneously, the fermented liquid, liquid starter and dough style starter are stored at -20 ℃ to investigate if the sourdough microorganisms can be preserved. The test is to shorten some of steps in the process The results show that the better quality of sourdough bread making and stability of fermentation during processes is the refrigerated starter in bag method. The refresh process can be last for more than 25 times. So, the method shall be applied to natural bread making in bakeries. The phase of microorganisms changed after the dough style starter is stored at 10 ℃ and -20 ℃, respectively for couple days. The sorts can contribute itself to baking size and taste and yeast is active. Additionally, LAB has a better production of acid. After freeze drying of pre-starter, the amount of LAB and yeast can be preserved better and longer than those in the fermented liquid and pre-starter frozen directly at -20 ℃. Therefore, in the future, preserving the developed natural LAB and yeast can be done by using freeze dried pre-starter. Therefore the whole process can be shorten. In the whole process, a key to make the sourdough bread containing unique tastes consists in long-time fermentation. Because longer time is required for yeast to ferment, this feature also offers LAB enough time to grow and metabolize. Thus, the organic acid and volatile flavor both are made. This made the sourdough bread unique sour and sweet taste.
Los estilos APA, Harvard, Vancouver, ISO, etc.
47

Young, Kelly Victoria. "Variation in prey availability and feeding success of larval Radiated Shanny (Ulvaria subbifurcata Storer) from Conception Bay, Newfoundland". Thesis, 2008. http://hdl.handle.net/1828/1024.

Texto completo
Resumen
Recruitment of pelagic fish populations is believed to be regulated during the planktonic larval stage due to high rates of mortality during the early life stages. Starvation is thought to be one of the main sources of mortality, despite the fact that there is rarely a strong correlation between the feeding success of larval fish and food availability as measured in the field. This lack of relationship may be caused in part by (i) inadequate sampling of larval fish prey and (ii) the use of total zooplankton abundance or biomass as proxies for larval food availability. Many feeding studies rely on measures of average prey abundance which do not adequately capture the variability, or patchiness, of the prey field as experienced by larval fish. Previous studies have shown that larvae may rely on these patches to increase their feeding success. I assess the variability in the availability of larval fish prey over a range of scales and model the small-scale distribution of prey in Conception Bay, Newfoundland. I show that the greatest variability in zooplankton abundance existed at the meter scale, and that larval fish prey were not randomly distributed within the upper mixed layer. This will impact both how well we can model the stochastic nature of larval fish cohorts, as well as how well we can study larval fish feeding from gut content analyses. Expanding on six years of previous lab and field studies on larval Radiated Shanny (Ulvaria subbifurcata) from Conception Bay, Newfoundland, I assess the feeding success, niche breadth (S) and weight-specific feeding rates (SPC, d-1) of the larvae to determine whether there are size-based patterns evident across the years. I found that both the amount of food in the guts and the niche breadth of larvae increased with larval size. There was a shift from low to high SPC with increasing larval size, suggesting that foraging success increases as the larvae grow. My results suggest that efforts should be made to estimate the variability of prey abundance at scales relevant to larval fish foraging rather than using large-scale average abundance estimates, since small-scale prey patchiness likely plays a role in larval fish feeding dynamics. In addition, the characteristics of zooplankton (density, size and behaviour) should be assessed as not all zooplankton are preyed upon equally by all sizes of larval fish. Overall, this thesis demonstrates that indices based on averages fail to account for the variability in the environment and in individual larval fish, which may be confounding the relationship between food availability and larval growth.
Los estilos APA, Harvard, Vancouver, ISO, etc.
También puede estar interesado en las bibliografías sobre el tema "Bad breath" para otros tipos de fuentes:
Artículos de revistas Libros
Ofrecemos descuentos en todos los planes premium para autores cuyas obras están incluidas en selecciones literarias temáticas. ¡Contáctenos para obtener un código promocional único!

Pasar a la bibliografía