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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.
351

La relación entre la experiencia de marca y el comportamiento del consumidor durante el proceso de compra en la MAC Store de Real Plaza / The relationship between brand experience and consumer behavior during the purchasing process at the Real Plaza Salaverry MAC Store

Armas Nizama, Juan Carlos, Ortiz Príncipe, Stefany 17 August 2020 (has links)
El crecimiento del sector cosméticos y del retail en el Perú, han ocasionado el ingreso de nuevas marcas mediante tiendas especializadas, por lo cual crear experiencia de marca es un punto clave para diferenciarse de la competencia. En consecuencia, se seleccionó la marca MAC Cosmetics por ser líder mundial en el sector de cosméticos, su influencia de marca y el profesionalismo de su personal en el punto de venta. En esta investigación, se busca validar cuatro hipótesis: la relación entre las variables “Experiencia de marca” y “Comportamiento del consumidor”. Así como la relación entre “Experiencia de marca” y cada una de las dimensiones del comportamiento del consumidor como: Comunicación boca a boca, intención de compra continua y disposición a pagar más. Para ello, se aplicó la siguiente estructura de investigación: en primer lugar, se realizó una investigación cualitativa a través de 3 entrevistas en profundidad, con la finalidad de conocer más sobre el sector de cosméticos, sobre la marca y el comportamiento del consumidor; en segundo lugar, una investigación cuantitativa correlacional a través de una encuesta a 215 personas, tanto hombres como mujeres entre los 18 y 45 años de edad, que realizaron al menos una compra durante el último año en la MAC Store de Real Plaza Salaverry. Los resultados confirmaron que si hay relación entre las variables de las hipótesis mencionadas anteriormente y el beneficio que genera crear una buena experiencia de marca en la tienda de MAC Cosmetics / The growth of the cosmetic industry and retail in Peru has caused the entry of new brands through specialized stores. Therefore, creating brand experience is a key point in order to differentiate from the competition. In consequence, we chose MAC Cosmetics brand for being a world leader in the cosmetics industry, for its brand influence and for its employees’ professionalism in their point of sale. In this research, it seek to validate four hypotheses like the relationship between “Brand experience” and “Consumer behavior”. As well as the relationship between “Brand experience” and each of the consumer behavior dimensions, such as mouth-to-mouth communication, ongoing purchasing intention and willingness to pay more. To accomplish this, we applied the following research structure: Firstly, we used a qualitative research through three-in-depth interviews in order to learn more about the cosmetic industry, the brand and the consumer behavior. Secondly, the quantitative analysis was a correlational research through a survey for 215 people, both men and women between the range of 18 to 45 years old, who had made at least one purchase during the last year in The Real Plaza Salaverry MAC Store. The results have shown that there exists a relationship between the above-mentioned variables of the hypotheses and the benefit that a good brand experience delivers in a MAC Cosmetics store. / Tesis
352

Évaluation des paramètres nécessaires à la détermination de la Date de Durabilité Minimale (DDM) et de la Période après Ouverture (PAO) des émulsions cosmétiques. / Evaluation of the parameters required for the determination of BBD and PAO of cosmetic emulsions.

De vaugelade du breuillac, Segolene 02 May 2018 (has links)
Depuis le 11 juillet 2013, date d’application du Règlement cosmétique (CE) No 1223/2009, les metteurs sur le marché sont dans l’obligation de mentionner sur leurs produits la Date de Durabilité Minimale (DDM), ou si celle-ci excède 30 mois, la Période Après Ouverture (PAO). L’estimation de ces dates n’est pas encadrée réglementairement. Cosmetics Europe, l’Agence nationale de sécurité du médicament et des produits de santé, le Comité scientifique pour la sécurité du consommateur ou encore la Commission Européenne proposent des lignes directrices, mais les conditions d’étude pour la détermination de la DDM et de la PAO restent encore à l’appréciation de la personne responsable de la commercialisation du produit. L’objectif de ce travail était d’étudier les conditions nécessaires à la mise en place d’un protocole de mesure de la stabilité d’émulsions cosmétiques, permettant de déterminer la DDM du produit de manière fiable et rapide. Pour cela, une approche expérimentale sur une émulsion représentative de l’industrie cosmétique a été menée. L’évolution des paramètres organoleptiques, physico-chimiques et microbiologiques a été évaluée, en accéléré (température augmentée) et en temps réel. Une approche statistique a montré que les propriétés sensorielles évoluent différemment en fonction de la température et du matériau dans lequel l’émulsion est stockée. L’établissement d’un modèle de correspondance entre le vieillissement en conditions réelles et en conditions accélérées a pu être proposé pour certains paramètres physico-chimiques. Les études de microbiologie se sont tout d’abord concentrées sur la validation d’une méthode commerciale, alternative au dénombrement des germes aérobies totaux encadré par la norme ISO 21149, pour une application dans le domaine cosmétique. Après validation, la méthode a été utilisée comme un outil simple, rapide et économique pour le suivi de la stabilité microbiologique de l’émulsion de référence. La dégradation des conservateurs et de l’antioxydant présents dans la formule de référence a été suivie par chromatographie en phase gazeuse couplée à la spectrométrie de masse (GC-MS). Ce suivi a permis de mettre en évidence l’effet probable de la lumière sur la dégradation des actifs de l’émulsion. A ces tests ont été associés une stratégie analytique visant à étudier la photostabilité de l’émulsion. Les études ont porté sur deux molécules : l’acide déhydroacétique et l’alpha-tocophérol. La stratégie a permis de caractériser les mécanismes impliqués dans les réactions de photodégradation. La chromatographie en phase gazeuse couplée à la spectrométrie de masse multi-étapes (GC-MSn) et la chromatographie en phase liquide couplée à la spectrométrie de masse haute résolution en tandem (LC-HR-MS/MS) ont été utilisées pour la séparation et l'identification structurale des photoproduits. La détection des photoproduits majoritaires dans l’émulsion de référence, après irradiation UV-visible, montre la possible formation des photoproduits dans une matrice complexe de type émulsion huile/eau. Les résultats des tests de toxicité, in silico et/ou in vitro, ont démontré l’importance de prendre en compte la formation éventuelle de photoproduits dans l’évaluation de la sécurité d’un produit cosmétique. / According to Cosmetic Regulation 1223/2009, implemented in July 2013, the manufacturer must mention the Date of Minimum Durability (DMD), or if DMD exceeds 30 months, the Period After Opening (PAO) on the product packaging. At the present time, no text regulates the procedures applicable to the validation of a DMD or a PAO. Some guidelines are published by Cosmetics Europe, the National Agency for the safety of medicines and health products, the Scientific Committee for consumer safety, or the European Commission; but the evaluation remains at the discretion of the person responsible for marketing the product. In this context, this work proposes recommendations to establish a stability protocol in order to quickly determine the DMD. Experimental approaches on an emulsion representative of the major category in the cosmetics industry have been established. Organoleptic, physicochemical and microbiological stabilities were evaluated. The emulsion stability has been tested in accelerated conditions and in real time. A statistical approach has been proposed to evaluate the product shelf life according to its organoleptic properties. The sensory properties of the cosmetic emulsion changed differently depending on the temperature and the material in which it has been stored. A mathematical correlation between the results of studies under normal and those obtained under accelerated conditions has been proposed for some parameters. A microbiological study focused on the validation of a commercially available method, alternative to total count of aerobic microorganisms, normed by the ISO 21149 for cosmetic application. Once validated, this method has been used as an economical, quick and easy tool to evaluate the microbiological stability of cosmetic emulsions. Gas chromatography coupled with mass spectrometry was used to follow the degradation of antioxidant and preservatives. To take into account the photostability of the emulsion, an analytical strategy was proposed to identify the mechanisms involved in phototransformation reactions. The study focused on two molecules: dehydroacetic acid and alpha-tocopherol. Both gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) and liquid chromatography coupled with ultrahigh resolution mass spectrometry (LC-UHR-MS) were used for the separation and the structural identification of photoproducts. The main photoproducts were detected in the reference emulsion after UV-visible irradiation, thus showing the possible formation of photoproducts in a complex oil/water emulsion. Both in silico and in vitro toxicity tests highlighted the need for taking into account the potential formation of photoproducts in the safety evaluation of a cosmetic product.
353

Sminkat ansvar : Relationshantering på sociala medier / Makeup the responsibility : Relationships management on social media

Gustafsson, Lina, Julkunen, Hanna Nathassia Sabrina January 2019 (has links)
I samband med att dagens konsumenter blir allt mer medvetna om de globala, sociala och miljömässiga konsekvenser som vår konsumtion medför, har det på senare år ställt större krav ett på företagens arbetssätt mot ett mer hållbart och etiskt verksamhetsutövande. Av denna anledning har företagens ansvarstagande för miljön och samhället blivit en central fråga i företagsekonomiska diskussioner, även känt som Corporate Social Responsibility (CSR). Syftet med CSR- strategier är att ett företag, på eget bevåg integrerar sociala, miljömässiga, ekonomiska eller/och etiska hänsyn i sin affärsmodell, samt i relation till intressenter, utöver vad lagen kräver. CSR blir allt vanligare bland företag att använda som ett verktyg för att kommunicera sitt CSR-arbete är via sociala medier. Den ökade användningen av sociala medier har förändrat kommunikationen för både företag och konsumenter, då det har skapat nya möjligheter att integrera med varandra. Användningen av sociala medier kan därmed vara ett effektivt verktyg inom marknadskommunikation, då det kan användas som en direkt kommunikation till sina målgrupper, samt användas för att bygga, bevara och vårda relationen till sina konsumenter. Vidare har sociala mediers användning också ökat transparensen, då det skapar en tillgänglighet till information om företag, som konsumenter tidigare inte fått tillgång till. Detta ställer därmed krav på att företagens marknadskommunikation, inte minst inom CSR hanteras effektivt, då CSR är ett starkt debatterat ämne bland dagens konsumenter. Många företag ser möjligheterna med att använda sociala medier, däremot om det inte används eller hanteras rätt, kan det likväl visa sig vara ett hinder som det är en fördel. Eftersom sociala medier skapar en möjlighet för konsumenter att lämna feedback, som i många fall inom CSR kan vara negativt, skapar det också möjligheten till att enkelt sprida Negative Word of Mouth (NWOM), dvs negativa budskap om ett företag. Att kommunicera CSR på sociala medier kan således upplevas som en utmaning för företag. Kan företag hantera sociala medier kan det användas som ett effektivt marknadskommunikationsverktyg. Därför är det betydelsefullt att använda tydliga strategier som kan hantera möjliga konflikter som kan uppstå i samband med diskussioner om CSR på sociala medier. Behandlar företag inte konflikterna kan det påverka konsumenters attityder och köpintentioner, och slutligen deras relationer till ett varumärke. Syftet med studien är att undersöka och observera strategier inom marknadskommunikation med CSR-inriktning på sociala mediet Facebook [Facebooksidor]. Vidare kartlägger studien möjliga utmaningar som de observerade strategierna medför inom kosmetikabranschen, i syfte med att få en ökad förståelse för strategihanteringar inom marknadskommunikation. För att undersöka CSR-kommunikation på sociala medier har studien avgränsats till kosmetikabranschen som en empirisk kontext, då det i dagsläget pågår stora diskussioner om CSR inom branschen. Studien resulterade i en CSR-integrerad relationshanteringsmodell och som observerade två huvudkategorier: Verbala och Icke-verbala relationshanteringsstrategier. Dessa innefattar fyra olika hanteringsstrategier; tillmötesgående, defensiv, censurerande och oengagerade. Studien resulterade även i vilka utmaningar, dvs svårigheter företag har när de använder sociala medier [Facebooksidor] inom CSR. Det observerade tre omfattade utmaningar; (1), det är svårt att kompensera en missnöjd konsument ämnen inom CSR går bortom transaktionen och är mer baserat på en individs emotioner. Då CSR är ett komplext ämne, blir det utmanande för företaget att kompensera en missnöjd kund då CSR handlar om att integrera socialt och miljömässigt ansvarstagande i hela företagets affärsmodell. (2) CSR-diskussioner är svåra att hantera för företag med traditionella kundservice-strategier inom social media marketing och webcare. (3) Företag som inte har CSR integrerat i sin affärsmodell från grunden har svårt att skapa, bevara och vårda relationen till sina konsumenter inom CSR-diskussioner. / As today's consumers become increasingly aware of the global, social and environmental consequences that our consumption brings, has in recent years influenced companies' way towards business ethics and sustainability. Therefore, corporate responsibility for the environment and society has become a central subject in business decisions, also known as Corporate Social Responsibility (CSR). The purpose of CSR is to encourage and integrate the work of ethical, financial, social and environmental aspects of business processes, and in relation to stakeholders, in addition to what the law requires. One tool that is becoming more common among companies when communicating their CSR work, is via social media. The increased use of social media has changed the communication for both companies and consumers, as it has created new opportunities to integrate with one another. The use of social media can thus be an effective tool in market communication, as it can be used as a direct communication tool to its target groups, as well as be used to build, maintain and nurture the relationship with its consumers. In addition, social media has increased the transparency, as it creates accessibility to information, whereas the consumers have more information and insight about companies today. Which demands on companies' marketing communications to be handled effectively, not least in the field of CSR, since social responsibility is a highly debated topic among today's consumers. Companies are becoming more aware of the possibilities of using social media, however, if it is not used or handled properly, it can also prove to be an obstacle as it is an advantage. Since social media creates an opportunity for consumers to provide feedback, which in many cases within CSR can be negative, it can also create the opportunity to easily spread Negative Word of Mouth (NWOM). Thus, communicating CSR on social media can therefore be a challenge for companies. If companies can manage social media, it can be used as an effective marketing communication tool. Therefore, it is important to use strategies that can handle possible conflicts that may arise in discussions of CSR on social media. If it is not handled, it can affect consumers' attitudes and purchase intentions, and ultimately their relationships with a brand. The purpose of this study is to investigate and observe strategies in market communication with CSR discussions on the social media platform, Facebook [Facebook pages]. Furthermore, identify possible challenges that the observed strategies pose, with the aim of gaining an increased understanding of strategy management in market communication. To study CSR communication on social media, the study has delimited to the cosmetics industry, as an empirical context, due to currently great discussions about CSR among consumers. The study resulted in a CSR-integrated relationship management model and observed two main categories: Verbal and non-verbal relationship management strategies. which includes four different management strategies; accommodating, defensive, censorship and non-engaging. The study also resulted in different difficulties companies have when using social media [Facebook pages] within the field of CSR. It observed three major difficulties/challenges; (1) It is difficult to satisfy a displeased consumer within the concept of CSR, due to the concept of CSR goes beyond the transaction and it is more based on an individual's emotions. As CSR is a complex subject, the difficulty of compensating a dissatisfied customer becomes challenging as CSR is about integrating social and environmental responsibility into the entire business model. (2) CSR discussions are difficult to manage for companies with traditional customer service strategies in social media marketing and webcare. (3) Companies that do not have integrated CSR into their business model from start, finds it difficult to create, maintain and nurture the relationship with their consumers within CSR discussions.
354

Fonctionnalisation de polymères et applications en cosmétique / Polymers functionalization and applications in cosmetics

Delattre, Émilie 29 October 2013 (has links)
L’alcool polyvinylique a été fonctionnalisé avec des aldéhydes et des acides boroniques dans le but d’obtenir des polymères pouvant apporter de la brillance tout en étant solubles dans les formulations de rouges à lèvres ou de vernis à ongles. De bons taux de fonctionnalisation ont été obtenus permettant d’avoir une bibliothèque de poly(vinyl acétals) et de poly(vinyl esters boroniques) d’une cinquantaine de polymères. Une multi-fonctionnalisation du PVA a été effectuée pour obtenir des polymères alliant ces deux propriétés. Cinq poly(vinyl acétals) ont ainsi permis d’apporter une forte brillance à des rouges à lèvres. La E-poly-L-lysine a également été fonctionnalisée avec diverses cétones afin d’obtenir de nouvelles poly-4-imidazolidinones. Ces polymères sont prometteurs pour des applications dans des produits cosmétiques tels que des soins. Ils ont également été utilisés en catalyse organique asymétrique. / Poly(vinyl alcohol) has been functionalized with aldehydes and boronic acids to obtain polymers with high shining and being soluble in cosmetic formulations as lipsticks or nail polishes. Good grafting rates have been obtained permitting to have a library of about fifty poly(vinyl acetals) and poly(vinyl boronic esters). Multi-functionalization has been developped to obtain polymers having these both properties. Five polymers gave strong shining to lipsticks. E-poly-L-lysine was also functionalized with several ketones to obtain new poly-4-imidazolidinones. These polymers are promising for cosmetic applications as skincare products. They were also used for organocatalysis.
355

Avaliação das características do fango de Araxá-MG com finalidade de uso cosmético / Evaluation the characteristics of Fango from Araxá-MG with cosmetic purposes

Pereira, Fernanda Fialho 17 September 2008 (has links)
O tratamento cosmético facial e corporal que emprega o Fango vem sendo muito utilizado em clínicas de estética, com o intuito de melhorar a aparência da pele. A literatura científica carece de informações sobre alguns aspectos desta matéria-prima, como: as condições adequadas para sua coleta, preservando suas características químicas e microbiológicas; as especificações de qualidade da matéria-prima (física, química, microbiológica e toxicológica); e as metodologias analíticas de avaliação. A qualificação do Fango é primordial para o mesmo ser utilizado como matéria-prima de uso cosmético \"tal qual\" na pele ou veiculado em formulações cosméticas, a fim de alcançar a eficácia cosmética e garantir sua segurança de uso. Este trabalho visou a padronização do método de coleta do Fango na fonte e a das seguintes análises: física, físico-química, microbiológica, parasitológica, toxicológica do Fango provindo de Araxá-MG in natura e da lama negra (processada), com intuito de assegurar seu uso qualificado como matéria-prima em formulações cosméticas, uma vez que a literatura científica carece de estudos com este tipo de material. Os resultados obtidos quanto à segurança de uso foram satisfatórios, não ocorrendo a presença de microrganismos patogênicos tais como: Escherichia coli, coliformes fecais e totais, Staphylococcus aureus, Pseudomonas aeruginosa e Candida albicans (antes e depois da maturação), larva migrans e metais pesados. Os demais ensaios realizados para a caracterização do Fango como matéria-prima justificam sua aplicação em produtos cosméticos, como por exemplo, a presença do enxofre com potencial uso em formulações antissépticas e a argila tipo \"caulinita\" em preparações para diminuir a oleosidade da pele. / The facial and body cosmetic treatments applying the \"Fango\" can be seen nowadays on esthetic clinics\' catalogues. The scientific literature up nowadays does not have sufficient informations concerning this product, the correct procedures to collect it from the soil preserving its chemical and microbiological characteristics; the specifications on its physical, chemical, microbiological e toxicological qualities and the analytical methodologies involving on the it evaluation. The Fango\'s qualification is very important because it can be used alone (raw material) or incorporated in cosmetic formulations, in order to evaluate the safety and efficacy of final product. This is the only way it may be applied on cosmetics formulations designed to be applied on human skin. The aim of this research is to standard the collect conditions in thermal springs and standard such analysis: physical aspects, physic-chemical, microbiology, parasitological and toxicological of Thermal mud and Fango from Araxá-MG. The results obtained of this study showed that the Fango from Araxá-MG is safe to be applied in cosmetic formulations or direct on the human skin. The pathogenic microorganism such as: Escherichia coli, Staphylococcus aureus, Pseudomonas aeuruginosa and Candida Albicans were absent on the samples, and the same to Larva migrans and heavy metais. The physic-chemical analysis of Fango from Araxá-MG demonstrated its application in cosmetic products, as its capacity to improvement the skin\'s conditions, e.g. the presence of sulphur with antiseptic proprieties and organic compounds in order to use on the oily skin.
356

Avaliação da atividade anti-glicação de proteína por 4-nerolidilcatecol isolado de Pothormorphe umbellata (L.) Miq. / Evaluation of the protein anti-glycation activity of 4-nerolydilcatechol isolated from Pothomorphe umbellata (L.) Miq.

Nakamura, Mary Sanae 07 November 2007 (has links)
A glicação é uma reação não enzimática que ocorre entre proteínas e açúcares redutores e, é responsável pela formação de adultos e de ligações cruzadas entre proteínas, como por exemplo: a pentosidina, produto final de glicação avançada que se acumula em vários tecidos ao longo do tempo. A glicação é deletéria para o organismo e está associada a modificações estruturais em proteínas e alterações de suas funções específicas, tais como: atividade enzimática, capacidade de ligação e tempo de vida de proteínas, além de ser responsável pela produção de espécies reativas de oxigênio (EROS). O mecanismo de formação da pentosidina envolve reações oxidativas e, uma das estratégias para minimizá-Ia é o aumento da atividade antioxidante nos tecidos. A pariparoba (Pothomorphe umbellata (L.) Miq) demonstrou atividade antioxidante in vitro e in vivo quando aplicada sobre a pele. Essa atividade foi atribuída ao 4-nerolidilcatecol (4-NC), que se mostrou 10 vezes mais potente que o α-tocoferol. Os extratos de pariparoba também inibiram a lipoperoxidação espontânea da pele em camundongos sem pelo. Neste trabalho empregou-se o modelo de glicação de albumina de soro bovino (BSA) frente à D-ribose, com avaliação da fluorescência produzida pela pentosidina formada na reação. Avaliou-se igualmente a atividade do 4-NC em diferentes concentrações sobre a reação de glicação da BSA em presença de D-ribose após 24 horas, empregando-se a aminoguanidina como controle positivo. Nas condições experimentais o 4-NC não foi capaz de inibir a reação de glicação, ao contrário da aminoguanidina. Foi também utilizado modelo para avaliação da propriedade contrátil de fibroblastos em matriz tridimensional de gel de colágeno, glicado e não glicado com D-ribose. O 4-NC na concentração de 100 µM permitiu a manutenção da propriedade contrátil de fibroblastos em gel colágeno glicado. Estudos de glicação em maiores períodos de tempo devem ser realizados visando a confirmar a possível atividade anti-glicação deste composto. / Glycation is a non enzymatic reaction which occurs between proteins and reductor sugars, responsible for the formation of adducts and crosslinkers between proteins, such as, pentosidine, an advanced glycation end-product (AGE) which accumulates in many tissues during aging. AGEs accumulation is deleterious to the body and is associated with structural modifications in proteins and imbalance in their specific functions, such as: enzymatic activity, binding capacity, protein turnover and also responsible for the production of reactive oxygen species (ROS). The mechanism of pentosidine formation involves oxidative reactions. One of the strategies to reduce pentosidine formation is by increasing antioxidant activity in tissues. Pariparoba (Pothomorphe umbellata (L.) Miq. has showed antioxidant activity in vitro and in vivo when applied on the skin. This activity was attributed to 4-nerolydilcatechol (4-NC), which is 10 times more potent than α-tocopherol. Extracts of Pariparoba also inhibited the spontaneous lipid peroxidation in the skin of hairless mice. In this work, the bovine serum albumin (BSA) model for glycation with D-ribose, evaluated by pentosidine fluorescence spectroscopy was employed. The activity of 4¬NC was evaluated in different concentrations in this model after 24 hours. Aminoguanidine was used as positive control. In this experimental condition, 4-NC was not capable to inhibit the BSA glycation. We also evaluated the contractile properties of fibroblasts on tridimensional matriz of collagen gel glycated or not with D-ribose. 4-NC (100 µM) was able to keep the contractile capacity of fibroblasts in glycated collagen. Studies of glycation in longer periods of time should be made in order to further evaluate the possible anti-glycation activity of this compound.
357

Les implications juridiques des nanotechnologies / Legal implications of nanotechnology

Soldatenko, Alexandra 17 March 2017 (has links)
Alors qu’un nombre non négligeable de produits contenant des nanomatériaux est déjà présent sur les marchés, nous manquons de recul tant en ce qui concerne les risques pour la santé et l’environnement que les bénéfices qu’ils peuvent apporter à la société sur le long terme. La présente thèse aborde la question suivante : quel régime règlementaire est en mesure de procurer le plus haut niveau de protection contre les risques avérés ou suspectés des nanotechnologies tout en soutenant simultanément la compétitivité et l'innovation ? Bien que l’Union européenne et les Etats-Unis se soient efforcés de trouver des solutions nuancées en fonction des besoins, des capacités, des enjeux inhérents à chaque secteur concerné et de leurs traditions juridiques respectives, l’on ne peut que constater l’émergence d’une réglementation des nanotechnologies à géométrie variable. / While a significant number of products containing nanomaterials is already in widespread use, we have little understanding of risks and benefits they can bring to the society in the long term. The objective of this PhD thesis is to answer the following question: which regulatory framework can ensure a high level of protection against real or suspected risks of nanotechnologies while promoting competitiveness and innovation ? Although the European Union and the United States have attempted to find nuanced solutions according to the needs, capacities and challenges, which are proper to each sector concerned and their respective legal traditions, the emerging regulatory framework for nanotechnologies is characterised by a high degree of fragmentation.
358

Imagerie moléculaire d’empreintes digitales par spectrométrie de masse : potentiels et applications en science forensique

Lauzon, Nidia 04 1900 (has links)
No description available.
359

Avaliação da atividade anti-glicação de proteína por 4-nerolidilcatecol isolado de Pothormorphe umbellata (L.) Miq. / Evaluation of the protein anti-glycation activity of 4-nerolydilcatechol isolated from Pothomorphe umbellata (L.) Miq.

Mary Sanae Nakamura 07 November 2007 (has links)
A glicação é uma reação não enzimática que ocorre entre proteínas e açúcares redutores e, é responsável pela formação de adultos e de ligações cruzadas entre proteínas, como por exemplo: a pentosidina, produto final de glicação avançada que se acumula em vários tecidos ao longo do tempo. A glicação é deletéria para o organismo e está associada a modificações estruturais em proteínas e alterações de suas funções específicas, tais como: atividade enzimática, capacidade de ligação e tempo de vida de proteínas, além de ser responsável pela produção de espécies reativas de oxigênio (EROS). O mecanismo de formação da pentosidina envolve reações oxidativas e, uma das estratégias para minimizá-Ia é o aumento da atividade antioxidante nos tecidos. A pariparoba (Pothomorphe umbellata (L.) Miq) demonstrou atividade antioxidante in vitro e in vivo quando aplicada sobre a pele. Essa atividade foi atribuída ao 4-nerolidilcatecol (4-NC), que se mostrou 10 vezes mais potente que o α-tocoferol. Os extratos de pariparoba também inibiram a lipoperoxidação espontânea da pele em camundongos sem pelo. Neste trabalho empregou-se o modelo de glicação de albumina de soro bovino (BSA) frente à D-ribose, com avaliação da fluorescência produzida pela pentosidina formada na reação. Avaliou-se igualmente a atividade do 4-NC em diferentes concentrações sobre a reação de glicação da BSA em presença de D-ribose após 24 horas, empregando-se a aminoguanidina como controle positivo. Nas condições experimentais o 4-NC não foi capaz de inibir a reação de glicação, ao contrário da aminoguanidina. Foi também utilizado modelo para avaliação da propriedade contrátil de fibroblastos em matriz tridimensional de gel de colágeno, glicado e não glicado com D-ribose. O 4-NC na concentração de 100 µM permitiu a manutenção da propriedade contrátil de fibroblastos em gel colágeno glicado. Estudos de glicação em maiores períodos de tempo devem ser realizados visando a confirmar a possível atividade anti-glicação deste composto. / Glycation is a non enzymatic reaction which occurs between proteins and reductor sugars, responsible for the formation of adducts and crosslinkers between proteins, such as, pentosidine, an advanced glycation end-product (AGE) which accumulates in many tissues during aging. AGEs accumulation is deleterious to the body and is associated with structural modifications in proteins and imbalance in their specific functions, such as: enzymatic activity, binding capacity, protein turnover and also responsible for the production of reactive oxygen species (ROS). The mechanism of pentosidine formation involves oxidative reactions. One of the strategies to reduce pentosidine formation is by increasing antioxidant activity in tissues. Pariparoba (Pothomorphe umbellata (L.) Miq. has showed antioxidant activity in vitro and in vivo when applied on the skin. This activity was attributed to 4-nerolydilcatechol (4-NC), which is 10 times more potent than α-tocopherol. Extracts of Pariparoba also inhibited the spontaneous lipid peroxidation in the skin of hairless mice. In this work, the bovine serum albumin (BSA) model for glycation with D-ribose, evaluated by pentosidine fluorescence spectroscopy was employed. The activity of 4¬NC was evaluated in different concentrations in this model after 24 hours. Aminoguanidine was used as positive control. In this experimental condition, 4-NC was not capable to inhibit the BSA glycation. We also evaluated the contractile properties of fibroblasts on tridimensional matriz of collagen gel glycated or not with D-ribose. 4-NC (100 µM) was able to keep the contractile capacity of fibroblasts in glycated collagen. Studies of glycation in longer periods of time should be made in order to further evaluate the possible anti-glycation activity of this compound.
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Avaliação das características do fango de Araxá-MG com finalidade de uso cosmético / Evaluation the characteristics of Fango from Araxá-MG with cosmetic purposes

Fernanda Fialho Pereira 17 September 2008 (has links)
O tratamento cosmético facial e corporal que emprega o Fango vem sendo muito utilizado em clínicas de estética, com o intuito de melhorar a aparência da pele. A literatura científica carece de informações sobre alguns aspectos desta matéria-prima, como: as condições adequadas para sua coleta, preservando suas características químicas e microbiológicas; as especificações de qualidade da matéria-prima (física, química, microbiológica e toxicológica); e as metodologias analíticas de avaliação. A qualificação do Fango é primordial para o mesmo ser utilizado como matéria-prima de uso cosmético \"tal qual\" na pele ou veiculado em formulações cosméticas, a fim de alcançar a eficácia cosmética e garantir sua segurança de uso. Este trabalho visou a padronização do método de coleta do Fango na fonte e a das seguintes análises: física, físico-química, microbiológica, parasitológica, toxicológica do Fango provindo de Araxá-MG in natura e da lama negra (processada), com intuito de assegurar seu uso qualificado como matéria-prima em formulações cosméticas, uma vez que a literatura científica carece de estudos com este tipo de material. Os resultados obtidos quanto à segurança de uso foram satisfatórios, não ocorrendo a presença de microrganismos patogênicos tais como: Escherichia coli, coliformes fecais e totais, Staphylococcus aureus, Pseudomonas aeruginosa e Candida albicans (antes e depois da maturação), larva migrans e metais pesados. Os demais ensaios realizados para a caracterização do Fango como matéria-prima justificam sua aplicação em produtos cosméticos, como por exemplo, a presença do enxofre com potencial uso em formulações antissépticas e a argila tipo \"caulinita\" em preparações para diminuir a oleosidade da pele. / The facial and body cosmetic treatments applying the \"Fango\" can be seen nowadays on esthetic clinics\' catalogues. The scientific literature up nowadays does not have sufficient informations concerning this product, the correct procedures to collect it from the soil preserving its chemical and microbiological characteristics; the specifications on its physical, chemical, microbiological e toxicological qualities and the analytical methodologies involving on the it evaluation. The Fango\'s qualification is very important because it can be used alone (raw material) or incorporated in cosmetic formulations, in order to evaluate the safety and efficacy of final product. This is the only way it may be applied on cosmetics formulations designed to be applied on human skin. The aim of this research is to standard the collect conditions in thermal springs and standard such analysis: physical aspects, physic-chemical, microbiology, parasitological and toxicological of Thermal mud and Fango from Araxá-MG. The results obtained of this study showed that the Fango from Araxá-MG is safe to be applied in cosmetic formulations or direct on the human skin. The pathogenic microorganism such as: Escherichia coli, Staphylococcus aureus, Pseudomonas aeuruginosa and Candida Albicans were absent on the samples, and the same to Larva migrans and heavy metais. The physic-chemical analysis of Fango from Araxá-MG demonstrated its application in cosmetic products, as its capacity to improvement the skin\'s conditions, e.g. the presence of sulphur with antiseptic proprieties and organic compounds in order to use on the oily skin.

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