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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Die ultrastruktuur en innervering van die smaaksinsorgane by Clarias gariepinus (Burchell) (Teleostei : Siluroidei)

Nel, Maria Magdalena 03 September 2014 (has links)
D.Sc. / Please refer to full text to view abstract
192

Evaluation of masticatory, salivary and anthropometric function, presence of volatile sulphur compounds in young adults and changes in salivary gland pos adipogenesis induction in animal model = Avaliação da função mastigatória, salivar, antropométrica, presença de compostos sulfurados voláteis em adultos jovens e alterações em glândula salivar após indução de adipogênese em modelo animal / Avaliação da função mastigatória, salivar, antropométrica, presença de compostos sulfurados voláteis em adultos jovens e alterações em glândula salivar após indução de adipogênese em modelo animal

Carvalho, Polliane Morais de, 1981- 12 January 2014 (has links)
Orientador: Maria Beatriz Duarte Gavião / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-26T13:36:25Z (GMT). No. of bitstreams: 1 Carvalho_PollianeMoraisde_D.pdf: 2230005 bytes, checksum: a03e416e657adde52ad89b778975278c (MD5) Previous issue date: 2014 / Resumo: Este estudo investigou a função mastigatória, o paladar, a presença de compostos sulfurados voláteis (CSV) e a bioquímica salivar em sujeitos saudáveis (18-33 anos), e a indução de adipócitos em glândula salivar e suas implicações em modelo animal. Três estudos foram conduzidos, apresentados na forma de capítulos. Capítulo 1: Investigou a performance e habilidade mastigatória, paladar e a possível relação com gênero, índice de massa corporal (IMC), circunferência de cintura (CC) e fluxo salivar estimulado (Stim) e não estimulado (Unst). Foram avaliados 171 indivíduos, (125? 46?). A performance mastigatória foi determinada pela capacidade de fragmentação do Optocal plus e habilidade mastigatória com o uso da escala visual analógica (EVA). O paladar foi verificado pela percepção dos quatro sabores primários. A estatística descritiva, teste de normalidade, correlação, comparação e modelos de regressão foram utilizados, sendo as variáveis dependentes a função mastigatória e o paladar e as independentes: gênero, idade, variáveis antropométricas e fluxo salivar. Na análise de regressão linear múltipla, as variáveis independentes não predisseram o modelo para performance mastigatória. Com a habilidade mastigatória (HM) o modelo explicou 14% da variabilidade e para o paladar 5%. Os resultados indicaram que a performance não foi relacionada com parâmetros antropométricos e salivares em indivíduos jovens saudáveis. A habilidade foi relacionada com IMC, CC e gênero. O paladar foi fracamente relacionado ao IMC e CC. Capítulo 2: Verificou a bioquímica salivar e presença de CSV e a possível interferência do IMC, fluxo e pH stim/unst. Para a verificação dos CSV foram avaliados 71 voluntários (57? 14 ?), utilizando o aparelho Oral chromeTM. Foram determinadas as concentrações de proteína total, cálcio, fosfato, amilase e ureia em 171 voluntários (125? 46 ?), em saliva stim/unst. A bioquímica salivar foi semelhante em relação à antropometria. No entanto, as respectivas concentrações diferiram significativamente entre saliva Stim/Unst, com exceção da amilase. Os indivíduos apresentaram quantidades semelhantes de CSV em relação ao IMC. Em indivíduos com valores críticos de metilmercaptana (CH3SH) observou-se correlação significativa (r=0.51) com o pH (unst). Capítulo 3: Investigou o eventual aparecimento de adipócitos nas glândulas salivares em modelo animal (camundongos). A adipogênese foi realizada com dieta rica em gordura, e ainda via receptor de proliferadores de peroxissoma gamma (PPAR gama) com rosiglitazona. Western blot, histoquímica e imunoistoquímica foram utilizadas. Análise de microarray foi realizada para verificar o efeito da dieta. Anticorpos: fosfo-4E BP1 e tirosina hidroxilase marcaram a atividade de mTOR e nervos, respectivamente. O microarray mostrou um número significativo de alterações genéticas. Em relação à dieta observou-se baixa ou nenhuma expressão de fosfo 4E-BP1 e aumento na atividade de tirosina hidroxilase. Em camundongos tratados com rosiglitazona verificou-se ativação de mTOR e tirosina hidroxilase. Conclusão: Pelos resultados dos três capítulos concluiu-se que em indivíduos jovens e saudáveis a função mastigatória e paladar não foram influenciados pelo padrão salivar e foram fracamente relacionados ao antropométrico. A bioquímica salivar e presença de CSV foi semelhante em relação à antropometria. Observaram-se mudanças relacionadas à atividade do sistema nervoso em glândula salivar de camundongos devido à dieta rica em gordura ou ativação de PPAR gamma / Abstract: This study investigated masticatory function, the presence of volatile sulfur compounds (VSC) and salivary biochemistry in healthy subjects (18-33 years), and also the induction of adipocytes in the salivary gland and its implication in an animal model. Three studies were conducted, presented as chapters. Chapter 1: Investigated the performance and chewing ability, taste, and the possible relationship to gender, body mass index (BMI), waist circumference (WC) and stimulated salivary flow (Stim) and unstimulated (Unst). 171 individuals (125? 46?) were evaluated. Masticatory performance was determined by the ability of fragmentation Optocal plus and chewing ability with the use of visual analogue scale (VAS). Taste was verified by the perception of the four primary flavors. Descriptive statistics, normality tests, correlation, comparison and multiple linear regression models were used. In multiple linear regression performance was not predict by the independent variables in the model. With chewing ability the model explained 14% of variability and 5% for the taste. The results indicated that masticatory performance was not related to anthropometric parameters and saliva in healthy young subjects. The ability was related to BMI, WC and Gender. Taste was weakly related to BMI and WC. Chapter 2: Verify the salivary biochemistry and presence of VSC and the possible influence of BMI, flow and pH (Stim)/(Unst). For the verification of VSC 71 volunteers (14 57? ?) were assessed using the Oral chromeTM device. The concentrations of: total protein, calcium, phosphate, urea and amylase were investigated in 171 volunteers (46 125? ?) in saliva (Stim) / (Unst). Biochemical salivary were similar in respect of anthropometry. However, the concentrations differed significantly between saliva (Stim)/(Unst), with the exception of amylase. The sample presented similar amounts of CSV in relation to BMI. In individuals with critical values of methylmercaptan (CH3SH) we observed a significant correlation (r = 0:51) with pH Unst. The results indicate that in healthy young subjects salivary biochemistry and VSC exhibit similar behaviour in relation to BMI. The (CH3SH) when greater than the normal limit concentration was correlated to pH Unst. Chapter 3: We investigated the possible appearance of adipocytes in the salivary glands in animal model (mice). Adipogenesis was performed with high-fat diet, and also via peroxisome proliferator-gamma (PPAR gamma) with rosiglitazone . Western blot, histochemistry and immunohistochemistry were used. Microarray analysis was performed to assess the effect of diet. Antibodies: phospho-4E-BP1 and tyrosine hydroxylase marked mTOR and nerves activity, respectively. The microarray showed a large number of genetic changes. Regarding diet was observed low or no expression of phospho-4E-BP1 and an increase in tyrosine hydroxylase activity. In mice treated with rosiglitazone there was activation of mTOR and tyrosine hydroxylase. The results suggest that there are changes in salivary gland innervation before stimuli for adipogenesis. Conclusion: We concluded that in healthy young individuals masticatory function was not influenced by the salivary pattern and was weakly related to anthropometric. Salivary Biochemical and presence of CSV was similar in relation to anthropometry. There are alterations in the activity of the nervous system in the salivary glands of mice due high fat diet or activation of PPAR gamma / Doutorado / Anatomia / Doutora em Biologia Buco-Dental
193

Uma abordagem metodológica para quantificar os efeitos cognitivos na análise sensorial de alimentos / A methodological approach to quantify the cognitive effects in sensorial analysis of food

Ellen Cristina Moronte Tech 23 January 2013 (has links)
A preocupação crescente com o desenvolvimento de hábitos saudáveis e uma alimentação adequada vêm promovendo o avanço nas ciências dos alimentos, como também nas relações entre estes e o homem. Nas últimas décadas, a qualidade da análise sensorial tem sido estudada não apenas com base na interação entre o homem e o alimento, mas através da compreensão dos fatores subjetivos e emocionais que influenciam os consumidores. O interesse pelos aspectos emocionais que influenciam essas escolhas amplia os estudos para o terreno das ciências psicológicas, que procuram entender as bases neurocognitivas e analíticas do funcionamento cerebral como motivadores desses processos no homem. O trabalho em neurociência cognitiva tem vislumbrado novos paradigmas, com o desenvolvimento de novas técnicas de observação do cérebro, visando conhecer sua estrutura e função, além de permitir a associação de um comportamento clinico ou experimentalmente observado, não só a um correlato mental presumido, mas também a marcadores específicos da atividade mental observada. Neste sentido, a atividade elétrica cerebral adquirida usando-se o eletroencefalograma (EEG) vem sendo, recentemente, muito usada para monitoramento de eventos cerebrais. Portanto, este trabalho tem como objetivo propor um modelo de análise sensorial que permita avaliar quantitativamente a ação do estímulo gustativo no contexto cognitivo, utilizando o EEG. O experimento foi realizado no laboratório de Física Aplica e Computacional (LAFAC), na Universidade Estadual de São Paulo (USP), Campus Pirassununga, no período de maio/2011 a maio/2012, com 23 voluntários (13 do sexo feminino e 10 do sexo masculino), com idade entre 19 e 24 anos. Foram coletados os sinais de EEG destes voluntários no momento em que experimentavam 27 amostras do sabor doce, sendo nove delas a 0% (água), nove com 0,15% de sacarose (limiar) e nove com 5,0% (concentração máxima). Desta amostragem, foi selecionado um grupo de 7 voluntários (5 do sexo feminino e 2 do sexo masculino) para análise dos dados. Neste estudo constatou-se que quatro voluntários do sexo feminino e um do sexo masculino foram capazes de identificar, através de dados obtidos com o EEG, as diferentes dosagens de sacarose. Os resultados permitem concluir que o modelo de análise sensorial proposta, com a utilização de EEG, para avaliar os estímulos gustativos no contexto cognitivo foi satisfatória e permitiu com a utilização de processamento de sinais digitais e AGR (Análise Adaptativa de Gabor) quantificar com eficiência a percepção dos voluntários as diferentes dosagens apresentadas no experimento. Sugere-se que as diferentes percepções dos voluntários no geral, encontradas no EEG, representam as suas singularidades quanto aos significados atribuídos ao sabor e suas correlações. / The growing concern with the development of healthy habits and a balanced diet allows the progress in Food Science as well as in the relationship between human beings and food. In the last decades the quality of the sensorial analysis has been studied not based only on the interaction between human beings and food but also through the comprehension of subjective and emotional factors that influence customers. The interest in emotional aspects which influence such choices extends the studies to the field of Psychological Science that attempts to understand neurocognitive and analytical bases of brain functioning as motivating elements of those human processes. The work in Cognitive Neuroscience has glimpsed new paradigms due to the development of new techniques about brain observation with the purpose of getting to know its structure and function other than allowing the association of behavior observed experimentally or clinical behavior not considering only a presumed mental correlative but also specific markers of mental activity observed in advance. In that aspect the brain electrical activity acquired through electroencephalogram has been recently used to monitor brain events. Therefore, the aim of this work is to propose a sensorial analysis pattern which allows to evaluate quantitatively the action of taste stimuli within a cognitive context using electroencephalogram. The experiment was carried out in the Laboratory of Applied and Computational Physics (LAFAC) in the University of the State of São Paulo (USP), Pirassununga Campus, from May 2011 to May 2012 with 23 volunteers (13 women and 10 men) aging between 19 and 21 years old. The volunteers\' electroencephalogram signals were collected when they tasted 27 sweet flavored samples, being 9 of them with 0% of sucrose (water), 9 with 0.15% of sucrose (threshold), and 9 with 5% of sucrose (maximum concentration). Seven volunteers were selected from this experiment (5 women and 2 men) whose data was analyzed. In this study was found that four women and one man were able to identify, through the EEG data obtained with the different concentrations of sucrose. The results obtained allowed to conclude that the proposed sensorial analysis pattern using electroencephalogram to evaluate taste stimuli within the cognitive context was satisfactory and allowed, along with the use of digital signals processing and Gabor Adaptive Analysis (AGR), to analyze and to quantify efficiently the volunteers\' perception of different doses presented in the experiment. It is suggested that the different perceptions of volunteers in general, encountered in EEG, representing singularities as to the meanings attributed to taste and their correlations.
194

TASTING TEA, TASTING CHINA: TEAROOMS AND THE EVERYDAY CULTURE IN DALIAN

Hou, Yingkun 01 September 2021 (has links)
Tea is a beverage that has long been taken to symbolize a key aspect of Chinese tradition and history. However, it is one of many beverages drunk in contemporary China, where in recent times knowledge of wine has come to stand for the West and as a much-desired cultural capital. This dissertation examines everyday tea drinking and tea tasting in Dalian—a northeastern city in Liaoning Province, China. Through ethnography of practices, processes, and interactions taking place in daily events of tea drinking and tasting, this dissertation provides a window into social conflicts, ideas and desires, historical consciousness, and national identity, individualism, and collectivism, in a contemporary Chinese city. It explores questions of why and how people learn to taste tea by acquiring certain levels of knowledge and skill that is valued in tea culture, and how people drink and taste tea in different social scenarios and contexts. Then it explores the significance of tea drinking and tasting to people in their daily life and as part of ritualized social relations, and specifically in contrast to beverages such as wine. As representative of Chinese culture, tea tasting raises questions of how sensory capabilities should be honed and deployed, and the relationship between so-called “objective” scientific knowledge of taste and the tacit, embodied skill that is associated with traditional cultural understandings.
195

Zkoušení senzorických schopností posuzovatelů - zkoumání citlivosti chuti / Testing of sensory abilities of assessors - studying of taste sensitivity

Chytilová, Eliška January 2009 (has links)
The aim of this diploma thesis is to study the sensitivity of one of the five human senses - taste. It deals with anatomy of taste sense, taste perception and it also describes which kinds of taste we are able to identify. Sensory analysis is focused on human senses and their practical use. Consequently, the requirements for sensory assessors, requirements for sensory laboratory, methods used in sensory analysis and summary of legislation in this area are described in this thesis. In order to perform qualified sensory assessment, the laboratory needs accreditation. On this account the requirements of Czech accreditation institute are mentioned here. Methods suitable for studying of taste sensitivity of sensory assessors are chosen and validated in experimental part. Standard operating procedures are elaborated for these chosen methods.
196

Vliv technologie výroby na chutnost sýrů eidamského typu / Influence of producing technology on flavour of Edam cheese

Urbanová, Andrea January 2010 (has links)
This work deals with the problem of flavour of Edam cheeses, i.e. natural hard cheese with low heat curd. The samples came from dairy MILTRA B s. r. o. Městečko Trnávka. A number of aroma active substances contribute to flavour of cheese. From the chemical point of view they are volatile compounds, including alcohols, aldehydes, ketones, fatty acids, esters, lactones, terpenes etc. Their content increases during ripening by influence of proteolytic and lipolytic changes and creates aroma, which is characteristic for type of cheese. The development of these components was monitored in chosen Edam cheese (30 % fat in dry matter) by headspace-SPME/GC method. The fiber CARTM/PDMS 85 µm was used for extraction of aroma compounds. The samples were taken from cheesemilk up to technologically ripe cheese. In total 30 aromatic compounds were identified, their content increased during ripening. The first increase was observed after pressing and then especially in second part of ripening. For comparison Edam cheese samples were also sensorially evaluated during ripening. The ordinal scale and profile tests were used for evaluation of organoleptic properties (appearance, texture, taste, aroma). The sensory quality was improved during ripening, but significant changes were not observed with regard to fine taste and smell of Edam cheese given by globally low content of aroma active compounds.
197

The Influence of Taste Perception in Foraging Choices in Rusty Crayfish

Austin, Emily Lauren 24 May 2022 (has links)
No description available.
198

A New qPCR Assay to Detect Geosmin-Producing Cyanobacteria

Davis, Shane Brian 01 December 2019 (has links)
Taste-and-odor (T&O) compounds are frequently produced by cyanobacterial blooms in bodies of water. Geosmin, perhaps the most common T&O compound produced by these blooms, is not effectively removed by conventional water treatment processes and frequently causes the tap water to have an off flavor. Although geosmin is not harmful when ingested, it damages the consumers' confidence in the cleanliness of their water. There are treatment options for geosmin removal, but the most common methods are often not implemented until complaints are made by consumers.There has been an increasing amount of research on the use of polymerase chain reaction (PCR)-based methods that can detect the presence of the geosmin synthase gene which is responsible for the production of geosmin. If the geosmin synthase gene is found to be present in an emerging cyanobacterial bloom, water treatment facilities can prepare in advance to treat for geosmin. In this study, we developed a qPCR (quantitative polymerase chain reaction) assay that can detect the presence of the geosmin synthase gene in several species of cyanobacteria within the Anabaena genus. We tested our assay, as well as PCR assays designed by Giglio et al. (2008) and Suurnäkki et al. (2015) on extracted Anabaena flos-aquae DNA, biosynthesized Anabaena ucrainica DNA and DNA extracted from environmental samples of Deer Creek Reservoir, Strawberry Reservoir, and Utah Lake. It is important to note that the geosmin gene was not confirmed to be present in any of the environmental samples nor in the Anabaena flos-aquae DNA and our assay did not test positive on these samples. Our qPCR assay was very successful when used with the biosynthesized Anabaena ucrainica DNA. We used the results to estimate a DNA standard curve that can be used to estimate the starting concentration of the geosmin synthase gene. Because our assay was not successfully used with any extracted DNA, further testing and calibration may be necessary to produce a DNA standard curve that is representative of DNA that is extracted. Further calibration of the DNA standard curve was not done because there were no geosmin events during the course of the research.Development of PCR-based methods of detecting geosmin-producing cyanobacteria requires genetic sequencing information of the target-organisms. Thus, further development of PCR-based methods requires that the local geosmin-producers be identified and sequenced. Our assay as well as the assay designed by Moore (2019) can assist with the identification of these species by classifying their genus.
199

The Regulation of Epithelial Sodium Channels in Mammalian Taste Receptor Cells

Baquero Gonzalez, Arian F. 01 May 2009 (has links)
Nutrient recognition is one of the main physiological roles of the gustatory system. In mammals, it is well established that the taste of sodium salts is primarily mediated by sodium influx through the epithelial sodium channel. The epithelial sodium channel is a sodium-specific ion channel that is expressed across a wide range of transporting epithelia such as colon, kidney, and taste. In addition to its role as a salt taste receptor, sodium influx through the epithelial sodium channel is important systemically for maintaining sodium balance and blood pressure. Following our earlier work on the endocrine regulation of salt taste at the level of the epithelial sodium channel, we hypothesize that the epithelial sodium channel expressed in mouse taste receptor cells plays a central role in the restoration of salt and water balance. Using a multidisciplinary approach that includes patch clamp recording, functional sodium imaging, molecular biology, Western blotting, and behavioral assays, we have begun to investigate different mechanisms of the epithelial sodium channel regulation in the taste system. In the present study, we have demonstrated a number of mechanisms that regulate the epithelial sodium channel by both ions and/or hormones in mouse taste cells. In general, three new mechanisms of the epithelial sodium channel regulation were identified: (1) regulation of the epithelial sodium channel by chloride ions, (2) regulation of the epithelial sodium channel by insulin, and (3) alterations of the epithelial sodium channel function in diabetic taste cells. To test the relevance of one or more of these regulatory mechanisms in the animals' behavior, we used a variety of short-term behavioral assays. Interestingly, the results suggested that insulin regulates salt intake in rodents, which dovetails nicely with our functional and molecular findings. Consistent with insulin's physiological role in salt taste transduction, we investigated the modification of the epithelial sodium channel function during the onset of diabetes. Diabetic rodents displayed alterations in salt taste transduction via epithelial sodium channel from the gene level to the animals' behavior. These results are an example of how regulatory cues, like hormones, act on specific transduction elements to modulate the peripheral gustatory system.
200

Effect of menstrual cycle on hedonic response to gustatory stimuli

O'Toole, Laurie A. 01 January 1984 (has links)
The present experiment was conducted to determine the relationship between the human menstrual cycle and gustatory hedonic response. Hedonic response was defined as the perceived pleasantness or unpleasantness of a taste stimulus. Gender differences in taste hedonic have been observed; these may be due to differences in endocrine systems. Animal taste preferences are altered when reproductive hormonal status is experimentally manipulated. Previous researchers report that human females' hedonic responses to sucrose vary systematically with phase of menstrual cycle.

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