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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Patch test analysis using horizontal cross section of an underwater feature for multibeam echo sounding system

Kao, I-chieh 09 February 2009 (has links)
Multibeam system is a rather new technique for generating huge digital terrain model quickly. If the primitive data does not perform quality control and the calibration process, inconsistency among the axes of transducer, motion sensor and gyrocompass may results in unreasonable underwater topography. The problem in the hydrographic surveying in the practice is not easy to seek for the suitable seabed or underwater feature for patch test at present. This research attempts to use fewer horizontal cross section of an underwater feature to compute roll, pitch and yaw deviation angle that differs from traditional vertical profile computing approach for patch test. And using different survey line combination and different underwater topography condition to achieve independent solution of angle deviation . We also design the new processing order for patch test. It hopes to utilize this concept to carry out patch test by the common underwater feature or recycling man-made object for resolving this problem in the future. The experimental results show that new calibration can get the same achievement as the traditional calibration by the CARIS HIPS software, and the calibration results applied in the cross check lines can pass through IHO special standard. It shows that the calibration results not only suit for calibration survey lines, but also good for rest of the area. It proves the proposed new patch test is feasible.
2

Nickel allergy in a Swedish adolescent population and its relation to orthodontic treatment and lifestyle factors

Fors, Ronny January 2008 (has links)
Nickel stands out as the main cause of contact allergy in both children and adults, which has given rise to concern and the introduction of regulations by official bodies. Today´s youths are frequently exposed to body piercing and orthodontic treatment. Changes in youth lifestyle practices are also likely to influence nickel exposure and thus, the occurrence of nickel allergy. However, against patient and parental concern regarding nickel exposure to orthodontic appliances, often evoked by allergies following piercing, stand results from studies indicating that early orthodontic appliance treatment may reduce, rather than increase, prevalence of nickel allergy; a finding that has been suggested to result from tolerance induction by early exposure to nickel via the oral route. The objective of the present thesis was to investigate the association between nickel allergy and exposure to different orthodontic appliances and lifestyle, in particular piercing, as well as to study nickel release from orthodontic appliances into the oral cavity. Furthermore, one objective was to establish baseline prevalence data of nickel allergy in a Swedish adolescent population. Data was generated from a cross-sectional survey, in which about 6000 youths completed a questionnaire and almost 4500 of these were patch-tested for contact allergy. Information on exposure to orthodontic appliances was verified by dental records, whilst nickel content in saliva and dental biofilm was measured in a clinical study. Questionnaire data demonstrated a reduced risk of nickel allergy when orthodontic treatment preceded piercing (OR 0.5; 95 % CI 0.3-0.8) and similar results were found for data verified from dental records, however statistical significance was lost when adjusting for background factors (OR 0.6, 95 % CI 0.4-1.0). Exposure to full fixed appliances with NiTi-containing alloys, as well as a pooled ‘high nickel-releasing’ appliance group prior to piercing correlated with a significantly reduced risk of nickel allergy and a trend towards a reduced risk with exposure duration. Nickel could also be found in significantly higher concentrations from dental plaque samples, but not saliva samples, in orthodontic patients who were well into treatment compared to patients who had not been exposed to orthodontic appliances. The effect was not found to be due to differences in estimated dietary nickel intake between the two groups. Significantly more girls than boys (13.3 % versus 2.5 %) were found to be patch-test positive to nickel. Positive nickel tests were also most prevalent in occupational programmes and least prevalent in natural science programmes, indicating differences in lifestyle and exposure to nickel. Dropout from testing was handled using a missing-value analysis. This internal validation showed that our results overestimated the occurrence of nickel allergy to a minor degree. More girls than boys reported piercing, vegetarian/vegan diet, and smoking practices, whereas an interesting shift in tattooing prevalence was observed with a larger proportion of girls reporting this practice compared to boys. Sex, number of piercings, smoking and orthodontic appliance treatment prior to piercing were found to influence weighted risk estimates of nickel allergy. To conclude, although orthodontic patients are exposed to nickel intraorally, we found no increased risk of sensitising adolescents to nickel by the use of oral orthodontic appliances. On the contrary, early orthodontic treatment preceding piercing reduced the risk of nickel allergy by a factor of 1.5-2.0. This reduced risk appears to be associated with estimated nickel release of the appliance and duration of treatment, in all supporting a hypothesised induction of immunological tolerance via oral administration of nickel. Our study also showed a strong association between lifestyle and nickel allergy. Although there have been changes in lifestyle over time, as indicated by the strong shift in tattooing practices, no large change in nickel allergy prevalence was found compared with previous Swedish data. Our data will serve as a baseline for future studies of the effect of nickel exposure regulations, such as the Nickel Directive, and for studies of lifestyle changes and their effects on nickel allergy.
3

Nonlinear finite element treatment of bifurcation in the post-buckling analysis of thin elastic plates and shells

Bangemann, Tim Richard January 1995 (has links)
The geometrically nonlinear constant moment triangle based on the von Karman theory of thin plates is first described. This finite element, which is believed to be the simplest possible element to pass the totality of the von Karman patch test, is employed throughout the present work. It possesses the special characteristic of providing a tangent stiffness matrix which is accurate and without approximation. The stability of equilibrium of discrete conservative systems is discussed. The criteria which identify the critical points (limit and bifurcation), and the method of determination of the stability coefficients are presented in a simple matrix formulation which is suitable for computation. An alternative formulation which makes direct use of higher order directional derivatives of the total potential energy is also presented. Continuation along the stable equilibrium solution path is achieved by using a recently developed Newton method specially modified so that stable points are points of attraction. In conjunction with this solution technique, a branch switching method is introduced which directly computes any intersecting branches. Bifurcational buckling often exhibits huge structural changes and it is believed that the computation of the required switch procedure is performed here, and for the first time, in a satisfactory manner. Hence, both limit and bifurcation points can be treated without difficulty and with continuation into the post buckling regime. In this way, the ability to compute the stable equilibrium path throughout the load-deformation history is accomplished. Two numerical examples which exhibit bifurcational buckling are treated in detail and provide numerical evidence as to the ability of the employed techniques to handle even the most complex problems. Although only relatively coarse finite element meshes are used it is evident that the technique provides a powerful tool for any kind of thin elastic plate and shell problem. The thesis concludes with a proposal for an algorithm to automate the computation of the unknown parameter in the branch switching method.
4

Epikutantests mit parallel zur Standardreihe untersuchten Substanzen an Patienten der Dermatologischen Universitätsklinik Göttingen / Patch tests with parallel to the standard series examined substances at the Dermatology Clinic of the University of Göttingen

Safaei Nikoie, Mohammad Reza 23 October 2018 (has links)
No description available.
5

Caracterização fitoquímica e eficácia fotoprotetora clínica de formulações cosméticas contendo extrato do bagaço de uva Cabernet Sauvignon / Phytochemical identification and clinical photoprotective efficacy of cosmetic formulations containing Cabernet Sauvignon grape pomace extract.

Hübner, Alexandra de Almeida 02 October 2017 (has links)
Com o avanço no desenvolvimento industrial sustentável estão sendo exploradas novas aplicações de uso dos subprodutos agroindustriais. O bagaço de uva obtido a partir da vinificação ou produção de sucos mantém importantes quantidades de polifenóis em suas cascas, sementes e engaço após o processamento, úteis para proteção da pele contra os raios ultravioleta. Neste contexto, o objetivo do nosso estudo foi caracterizar quimicamente o extrato do bagaço de uva Cabernet Sauvignon e avaliar a sua segurança e eficácia clínica em fotoprotetor tópico. Nesta dissertação, o extrato hidroetanólico (70% v/v) do bagaço de uva total, incluindo cascas, sementes e engaços de Vitis vinifera L., foi obtido por percolação seguido de liofilização. Os ensaios divididos em duas etapas: i) In vitro: determinação dos fenólicos totais (FT) usando Folin-Ciocalteu e expresso em equivalentes de ácido gálico (GAE); flavonoides por meio da reação com tricloreto de alumínio e expresso em quercetina; atividade antioxidante do extrato e das formulações através da desativação de radicais livres de DPPH• expressa em equivalentes de Trolox (TE); identificação dos principais compostos fenólicos do extrato bruto por espectrometria de massa (HPLC/ESI-MS/MS); desenvolvimento de nove formulações usando o delineamento experimental; medição dos valores de transmitância das formulações referentes ao fator de proteção solar (FPS), fotoestabilidade e fator de proteção UVA (FP-UVA) através do equipamento Labsphere UV-2000S® e ii) Em seres humanos, apenas duas formulações foram avaliadas clinicamente, C sem extrato e com filtros UVA e UVB: butilmetoxidibenzoilmetano, etil-hexilmetoxicinamato e etil-hexildimetil PABA (11,5% p/p) e D com extrato (bagaço de uva 10% p/p) e filtros UV. Inicialmente, a segurança dermatológica, irritabilidade e sensibilização; fototoxicidade e fotossensibilização foram avaliadas pelo Teste de Contato Repetitivo em Humanos (HRIPT). Posteriormente, a eficácia fotoprotetora clínica foi testada na pele de dez voluntários. O teor de FT encontrado no extrato de bagaço de uva foi de 141,11 ± 3,38 mg GAE.g-1 e de flavonoides 3,01 ± 0,14 mg QE.g-1. A eficácia antioxidante das soluções metanólicas com extrato e fotoprotetor na concentração de 1 mg.mL-1 em peso seco em pH 5 e 7 foram aproximadamente: 707 µmol TE.g-1 e 520 µmol TE.g-1, respectivamente. Isto significa uma queda em torno de 26,45% da capacidade antioxidante do extrato quando incorporado à formulação. Foram identificadas por espectrometria de massa dezenove substâncias fenólicas, entre elas dímeros e trímeros de procianidinas, di-hidroflavonol, flavonóis e antocianidinas. Os resultados demonstraram efeito sinérgico entre os filtros UV e extrato vegetal no FPS e efeito antagônico com a variação do tempo de irradiação sobre as respostas do FPS, atividade antioxidante, comprimento de onda crítico, proteção UVA, proteção UVB e razão UVA/UVB. A melhor combinação eficiência-resposta foi detectada na formulação D com um aumento do FPS in vitro em cerca de 210%. Os testes de segurança não induziram qualquer reação adversa. A eficácia fotoprotetora clínica de D foi 21% (10,20 - 12,30) superior em relação à formulação C, demonstrando maior eficiência na proteção UVA. Sendo assim, C e D foram consideradas seguras para uso tópico e D estatisticamente superior tanto na proteção UVA quanto UVB comparado à amostra só associada de filtros. Logo, o bagaço de uva é um promissor ingrediente sustentável multifuncional útil para o uso em protetor solar. / With the advance in sustainable industrial development, new applications of agro-industrial by-products are being explored. Grape pomace obtained from winemaking or juice production keeps important amounts of polyphenols in their skins, seeds and stalks after processing that are useful for protection of skin against ultraviolet rays. In this context, the objective of our study was to chemically characterize Cabernet Sauvignon pomace extract and to evaluate its safety and clinical efficacy in topical photoprotector. The hydroethanolic extract (70% v/v) of the Vitis vinifera L. whole grape pomace, including seeds, skins and stalks, was obtained by percolation after lyophilization. The tests were divided into two stages: i) In vitro: total phenols (TF) using Folin-Ciocalteu and expressed in Gallic Acid Equivalent (GAE); flavonoids by reaction with aluminum trichloride and expressed as quercetin; antioxidant activity of the extract and formulations by inhibition by DPPH• expressed as Trolox equivalents (TE); identification of the main phenolic compounds of the crude extract by mass spectrometry (HPLC/ESI-MS/MS); development of nine formulations using experimental design and evaluated the SPF, photostability and UVA protection factor (UVA-PF) through the Labsphere UV-2000S® equipment; ii) In humans, only two formulations were clinically evaluated, C without extract and with UVA and UVB filters: butilmetoxidibenzoilmetano, etil-hexilmetoxicinamato and etil-hexildimetil PABA (11.5% w/w) and D with extract (10% w/w grape pomace) and filters UV. Initially, the dermatological safety, irritability and sensitization; phototoxicity and photosensitization were evaluated by the Human Repeat Insult Patch Test (HRIPT). After, the clinical photoprotective efficacy was tested on the skin of ten volunteers. The FT content found in the dried extract was 141.11 ± 3.38 mg GAE.g-1 and flavonoids 3.01 ± 0.14 mg QE.g-1. The antioxidant potential of the methanolic solutions with extracts and photoprotectors at the concentration of 1 mg.ml-1 in dry weight and at pH 5 and 7 were around: 707 µmol TE.g-1 and 520 µmol TE.g-1, respectively. This means a drop of about 26.45% of the antioxidant capacity of the extract when incorporated into the formulation. Mass spectrometry identified nineteen phenolic substances, among them procyanidins dimers and trimmers, di-hydroflavonol, flavonols and anthocyanin. The results showed a synergistic effect between the UV filters and the herbal extract in the SPF and the antagonistic effect with the variance of the irradiation time in the SPF responses, antioxidant activity, critical wavelength, UVA protection, UVB protection and UVA/UVB ratio. The best efficiency-response combination was detected in the D formulation with an in vitro SPF increase of about 210%. Safety tests did not induce any adverse reaction. The clinical efficiency of D photoprotection was 21% (10.20 - 12.30) higher than the C formulation, demonstrating high efficiency in UVA protection. Thus, C and D were considered safe for topical use and D statistically superior in both UVA and UVB protection to the only combined sample of filters. Therefore, grape pomace is a promising multifunctional sustainable ingredient qualified to be used in sunscreen industry.
6

Caracterização fitoquímica e eficácia fotoprotetora clínica de formulações cosméticas contendo extrato do bagaço de uva Cabernet Sauvignon / Phytochemical identification and clinical photoprotective efficacy of cosmetic formulations containing Cabernet Sauvignon grape pomace extract.

Alexandra de Almeida Hübner 02 October 2017 (has links)
Com o avanço no desenvolvimento industrial sustentável estão sendo exploradas novas aplicações de uso dos subprodutos agroindustriais. O bagaço de uva obtido a partir da vinificação ou produção de sucos mantém importantes quantidades de polifenóis em suas cascas, sementes e engaço após o processamento, úteis para proteção da pele contra os raios ultravioleta. Neste contexto, o objetivo do nosso estudo foi caracterizar quimicamente o extrato do bagaço de uva Cabernet Sauvignon e avaliar a sua segurança e eficácia clínica em fotoprotetor tópico. Nesta dissertação, o extrato hidroetanólico (70% v/v) do bagaço de uva total, incluindo cascas, sementes e engaços de Vitis vinifera L., foi obtido por percolação seguido de liofilização. Os ensaios divididos em duas etapas: i) In vitro: determinação dos fenólicos totais (FT) usando Folin-Ciocalteu e expresso em equivalentes de ácido gálico (GAE); flavonoides por meio da reação com tricloreto de alumínio e expresso em quercetina; atividade antioxidante do extrato e das formulações através da desativação de radicais livres de DPPH• expressa em equivalentes de Trolox (TE); identificação dos principais compostos fenólicos do extrato bruto por espectrometria de massa (HPLC/ESI-MS/MS); desenvolvimento de nove formulações usando o delineamento experimental; medição dos valores de transmitância das formulações referentes ao fator de proteção solar (FPS), fotoestabilidade e fator de proteção UVA (FP-UVA) através do equipamento Labsphere UV-2000S® e ii) Em seres humanos, apenas duas formulações foram avaliadas clinicamente, C sem extrato e com filtros UVA e UVB: butilmetoxidibenzoilmetano, etil-hexilmetoxicinamato e etil-hexildimetil PABA (11,5% p/p) e D com extrato (bagaço de uva 10% p/p) e filtros UV. Inicialmente, a segurança dermatológica, irritabilidade e sensibilização; fototoxicidade e fotossensibilização foram avaliadas pelo Teste de Contato Repetitivo em Humanos (HRIPT). Posteriormente, a eficácia fotoprotetora clínica foi testada na pele de dez voluntários. O teor de FT encontrado no extrato de bagaço de uva foi de 141,11 ± 3,38 mg GAE.g-1 e de flavonoides 3,01 ± 0,14 mg QE.g-1. A eficácia antioxidante das soluções metanólicas com extrato e fotoprotetor na concentração de 1 mg.mL-1 em peso seco em pH 5 e 7 foram aproximadamente: 707 µmol TE.g-1 e 520 µmol TE.g-1, respectivamente. Isto significa uma queda em torno de 26,45% da capacidade antioxidante do extrato quando incorporado à formulação. Foram identificadas por espectrometria de massa dezenove substâncias fenólicas, entre elas dímeros e trímeros de procianidinas, di-hidroflavonol, flavonóis e antocianidinas. Os resultados demonstraram efeito sinérgico entre os filtros UV e extrato vegetal no FPS e efeito antagônico com a variação do tempo de irradiação sobre as respostas do FPS, atividade antioxidante, comprimento de onda crítico, proteção UVA, proteção UVB e razão UVA/UVB. A melhor combinação eficiência-resposta foi detectada na formulação D com um aumento do FPS in vitro em cerca de 210%. Os testes de segurança não induziram qualquer reação adversa. A eficácia fotoprotetora clínica de D foi 21% (10,20 - 12,30) superior em relação à formulação C, demonstrando maior eficiência na proteção UVA. Sendo assim, C e D foram consideradas seguras para uso tópico e D estatisticamente superior tanto na proteção UVA quanto UVB comparado à amostra só associada de filtros. Logo, o bagaço de uva é um promissor ingrediente sustentável multifuncional útil para o uso em protetor solar. / With the advance in sustainable industrial development, new applications of agro-industrial by-products are being explored. Grape pomace obtained from winemaking or juice production keeps important amounts of polyphenols in their skins, seeds and stalks after processing that are useful for protection of skin against ultraviolet rays. In this context, the objective of our study was to chemically characterize Cabernet Sauvignon pomace extract and to evaluate its safety and clinical efficacy in topical photoprotector. The hydroethanolic extract (70% v/v) of the Vitis vinifera L. whole grape pomace, including seeds, skins and stalks, was obtained by percolation after lyophilization. The tests were divided into two stages: i) In vitro: total phenols (TF) using Folin-Ciocalteu and expressed in Gallic Acid Equivalent (GAE); flavonoids by reaction with aluminum trichloride and expressed as quercetin; antioxidant activity of the extract and formulations by inhibition by DPPH• expressed as Trolox equivalents (TE); identification of the main phenolic compounds of the crude extract by mass spectrometry (HPLC/ESI-MS/MS); development of nine formulations using experimental design and evaluated the SPF, photostability and UVA protection factor (UVA-PF) through the Labsphere UV-2000S® equipment; ii) In humans, only two formulations were clinically evaluated, C without extract and with UVA and UVB filters: butilmetoxidibenzoilmetano, etil-hexilmetoxicinamato and etil-hexildimetil PABA (11.5% w/w) and D with extract (10% w/w grape pomace) and filters UV. Initially, the dermatological safety, irritability and sensitization; phototoxicity and photosensitization were evaluated by the Human Repeat Insult Patch Test (HRIPT). After, the clinical photoprotective efficacy was tested on the skin of ten volunteers. The FT content found in the dried extract was 141.11 ± 3.38 mg GAE.g-1 and flavonoids 3.01 ± 0.14 mg QE.g-1. The antioxidant potential of the methanolic solutions with extracts and photoprotectors at the concentration of 1 mg.ml-1 in dry weight and at pH 5 and 7 were around: 707 µmol TE.g-1 and 520 µmol TE.g-1, respectively. This means a drop of about 26.45% of the antioxidant capacity of the extract when incorporated into the formulation. Mass spectrometry identified nineteen phenolic substances, among them procyanidins dimers and trimmers, di-hydroflavonol, flavonols and anthocyanin. The results showed a synergistic effect between the UV filters and the herbal extract in the SPF and the antagonistic effect with the variance of the irradiation time in the SPF responses, antioxidant activity, critical wavelength, UVA protection, UVB protection and UVA/UVB ratio. The best efficiency-response combination was detected in the D formulation with an in vitro SPF increase of about 210%. Safety tests did not induce any adverse reaction. The clinical efficiency of D photoprotection was 21% (10.20 - 12.30) higher than the C formulation, demonstrating high efficiency in UVA protection. Thus, C and D were considered safe for topical use and D statistically superior in both UVA and UVB protection to the only combined sample of filters. Therefore, grape pomace is a promising multifunctional sustainable ingredient qualified to be used in sunscreen industry.
7

Nickel allergy and hand eczema : epidemiological aspects

Josefson, Anna January 2010 (has links)
Nickel allergy is the most prevalent contact allergy and has been discussed as a possible riskfactor for hand eczema. However, hand eczema is one of the most frequently occurring skindiseases and has multifactorial origin. The aim of this thesis was to study the association between nickel allergy and hand eczema in the general population. There are only a fewpopulation-based studies previously published, that include patch testing. In addition, this thesis aimed to evaluate methods to follow the prevalence of nickel allergy.The study cohort consisted of 908 women who had been patch tested for the occurrence of nickel allergy as schoolgirls. Twenty years later, they were invited to participate in a follow-up questionnaire study. The response rate was 81%. In total, 17.6% of respondents reported handeczema after the age of 15 years and there was no statistically significant difference in the occurrence of hand eczema between those who were nickel-positive and those who were nickel negativeas schoolgirls. To further investigate possible links, another study was performed,which included a second questionnaire, a clinical investigation and patch testing. All schoolgirls from the baseline study who were still living in the area as adults were invited to participate and the participation rate was 77%. Patch test showed 30.1% nickel-positive individuals.When all participants were included in the analysis, there was no statistically significant difference between nickel-positive and nickel-negative women regarding occurrence of hand eczema. The most important risk factor for hand eczema was childhood eczema. Adjusted prevalence proportion ratio (PPR) for hand eczema after age 15 in relation to nickel patch testresults was 1.03 (95% CI 0.71--1.50) and in relation to childhood eczema 3.68 (95% CI 2.45--5.54). When women with and without history of childhood eczema were analyzed separately, the hand eczema risk was doubled in nickel-positive women without history of childhood eczema. In conclusion, the risk of hand eczema in nickel-positive women may previously havebeen overestimated. Next, the validity of self-reported nickel allergy was investigated. In the established cohort; two questions regarding nickel allergy were compared with patch test results. The validity of self-reported nickel allergy was low, and the questions regarding nickel allergy overestimated the true prevalence of nickel allergy. The positive predictive values were 59% and 60%. Another method for estimating the prevalence of nickel allergy, namely self-patch testing, was validated in the last study. In total, 191 patients from three different dermatology departments participated. The validity of self-testing for nickel allergy was adequate, with sensitivity 72%and proportion of agreement 86%. / Nickelallergi är vanligt förekommande. Prevalensen i Skandinavien är 15--25% hos kvinnor och cirka 3% hos män. Sambandet mellan nickelallergi och uppkomst av handeksem har tidigare diskuterats och i vissa studier anges att 30--45% av alla individer med nickelallergi får handeksem. Det finns dock endast ett fåtal publicerade studier där personer ur normalbefolkningen har lapptestats för nickel. Handeksem ärvanligt och har ofta flera olika kombinerade orsaker. Det övergripande syftet med avhandlingen var att studera nickelallergins betydelse för uppkomst av handeksem. Detfinns ett intresse av att följa förekomsten av nickelallergi över tid, speciellt sedan det i början av 2000-talet infördes ett EU-direktiv som begränsar nickelinnehåll i klockor,smycken, metallknappar etc. Ytterligare ett syfte med avhandlingen var att utvärderaepidemiologiska metoder för att följa förekomsten av nickelallergi.Den första studien var en uppföljningsstudie av 908 flickor ur normalbefolkningen,vilka i skolåldern lapptestats med nickel. Tjugo år senare skickades en enkät till dessa kvinnor, svarsfrekvensen var hög (81%). Förekomsten av självrapporterat handeksemefter 15 års ålder var 17.6%. Det förelåg ingen signifikant skillnad i förekomst avhandeksem mellan de kvinnor som var nickelallergiska som barn jämfört med dem som inte var nickelallergiska. År 2006 utfördes ytterligare en studie, som inkluderade de kvinnor som fortfarande bodde i Örebro län. Studien omfattade en klinisk undersökning av händerna samt ett lapptest. 30% av kvinnorna var positiva för nickel.Det förelåg ingen signifikant skillnad i förekomst av handeksem mellan de som var positiva för nickel och de som var negativa. Vid separat analys av de kvinnor som angav tidigare barneksem jämfört med dem som aldrig hade haft barneksem visade det sig att risken för handeksem var dubbelt så stor hos nickelallergiker i den gruppen som aldrig hade haft barneksem. Båda studierna visade att barneksem var den största riskfaktorn för att få handeksem som vuxen, med en 3-4 gånger ökad risk. Den tredje studien var en validering av självrapporterad nickelallergi. Överensstämmelsen var låg mellan enkätfrågor gällande nickelallergi och lapptestverifierad nickelallergi. Av dem som själva bedömde sig vara nickelallergiska var endast 59% positiva enligt lapptest. För att följa förekomsten av nickelallergi i befolkningen behövs därför andra metoder. I den fjärde studien utvärderades ett självtest för nickelallergi. 191 patienter från tre olika hudkliniker i Sverige deltog i studien. Validiteten för metoden självtest var tillfredsställande, sensitiviteten var 72%och graden av överensstämmelse var 86%.
8

Avaliação da relevância do teste cutâneo de contato alérgico de leitura tardia no diagnóstico da sensibilização a Dermatophagoides pteronyssinus, Dermatophagoides farinae e Blomia tropicalis

Lima, Ingrid Pimentel Cunha Magalhães de Souza 24 August 2018 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-10-10T13:46:10Z No. of bitstreams: 1 ingridpimentelcunhamagalhaesdesouzalima.pdf: 1571962 bytes, checksum: 521511b66ed89adf27b01a59f98c7cfc (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-10-16T13:34:14Z (GMT) No. of bitstreams: 1 ingridpimentelcunhamagalhaesdesouzalima.pdf: 1571962 bytes, checksum: 521511b66ed89adf27b01a59f98c7cfc (MD5) / Made available in DSpace on 2018-10-16T13:34:14Z (GMT). No. of bitstreams: 1 ingridpimentelcunhamagalhaesdesouzalima.pdf: 1571962 bytes, checksum: 521511b66ed89adf27b01a59f98c7cfc (MD5) Previous issue date: 2018-08-24 / O objetivo do presente estudo é avaliar a positividade do teste cutâneo de contato alérgico de leitura tardia para Dermatophagoides pteronyssinus, Dermatophagoides farinae e Blomia tropicalis em pacientes com doenças respiratórias como rinite alérgica e/ou asma com ou sem dermatite atópica. A maioria dos trabalhos existentes nessa área de pesquisa se refere ao emprego desse método diagnóstico na dermatite atópica, mas, neste estudo, a amostra é composta, principalmente, de pacientes com doenças respiratórias. Blomia tropicalis é um ácaro muito incidente no Brasil e só há dois trabalhos que envolvem o emprego deste ácaro da poeira domiciliar típico de países de clima tropical. Os pacientes foram selecionados pela história clínica e foram divididos em dois grupos: I- pacientes com doenças respiratórias, como asma e/ou rinite alérgica, com dermatite atópica e II- pacientes somente com doenças respiratórias. Foi realizado teste cutâneo de leitura imediata e teste de cutâneo de contato alérgico de leitura tardia para os três ácaros no mesmo dia. O teste de contato alérgico foi retirado em 48 horas. A análise estatísitica foi realizada em porcentagens e a tabela 1 apresenta as variáveis por sexo e por grupo estudado. Setenta e quatro pacientes, com idades de 2 a 60 anos, foram incluídos neste estudo; 16 no grupo I e 58 no grupo II. Considerando o teste cutâneo de leitura imediata, o ácaro mais prevalente foi o Dermatophagoides pteronyssinus, seguido pelo Dermatophagoides farinae e Blomia tropicalis. Em relação ao teste cutâneo de contato alérgico de leitura tardia, o ácaro que induziu maior positividade foi o Dermatophagoides farinae (78,4%), seguido pelo Dermatophagoides pteronyssinus (77%) e Blomia tropicalis (52,7%). Comparando o teste cutâneo de leitura imediata com o teste cutâneo de contato alérgico de leitura tardia, 53 pacientes (71,6%) foram positivos para ambos os testes, e 30 (56,6%) foram positivos ao mesmo ácaro. Foram identificados seis pacientes (8%) que tinham história clinica positiva para alergia e só apresentavam positividade no teste cutâneo de contato alérgico de leitura tardia. Estes resultados sugerem que o teste cutâneo de contato alérgico de leitura tardia é relevante e deve ser considerado como um teste diagnóstico adicional, em pacientes com história clínica positiva para doenças respiratórias, com teste cutâneo de leitura imediata negativa. / The aim of this study is to evaluate the positivity rates of atopy patch tests for Dermatophagoides pteronyssinus, Dermatophagoides farinae and Blomia tropicalis in patients with respiratory diseases such as asthma and allergic rhinitis with or without atopic dermatitis. Most studies have been performed with atopic dermatitis patients, but in our study, most of the patients had respiratory conditions. Blomia tropicalis is a mite that is prevalent in tropical areas, such as Brazil, and only two publications include these three mites, which are present in Brazil. The patients’ clinical histories were collected, and the patients were subjected to skin prick and patch tests with the three different house dust mites on the same day. The patch tests were examined 48 hours later, and then, the patients were divided into two groups: I- patients with respiratory diseases, such as asthma and/or rhinitis, and atopic dermatitis and II-patients with only respiratory diseases. The statistical analysis results are presented as percentages, and Table 1 presents the variables by gender and groups studied. A total of 74 patients ranging in age from 2 to 60 years old were included in this study; 16 patients were included in group I and 58 were included in group II. In the skin prick tests, the most prevalent mite that evoked a reaction was Dermatophagoides pterronyssinus, followed by Dermatophagoides farinae and Blomia tropicalis. Regarding the atopy patch tests, the mite that most frequently induced a positive reaction was Dermatophagoides farinae (78.4%), followed by Dermatophagoides pteronyssinus (77%) and Blomia tropicalis (52.7%). A comparison between the skin prick and atopy patch tests revealed that 53 patients (71.6%) were positive on both tests, and 30 (56.6%) patients were positivite for the same mite. We found six patients (8%) who had a positive clinical history of allergy and only exhibited positivity on the atopy patch test. These results suggest that the mite atopy patch test is relevant and should be considered as an additional test for patients with clinical histories of allergic respiratory disease who have negative prick test results.
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[en] THE HYBRID BOUNDARY ELEMENT METHOD FOR GRADIENT ELASTICITY PROBLEMS / [pt] O MÉTODO HÍBRIDO DE ELEMENTOS DE CONTORNO PARA PROBLEMAS DE ELASTICIDADE GRADIENTE

DANIEL HUAMAN MOSQUEIRA 28 January 2015 (has links)
[pt] Atualmente está bem difundido o uso de novas modelagens matemáticas para o estudo do comportamento de micro e nano sistemas mecânicos e eléctricos. O problema de escala é notável quando o tamanho das moléculas, partículas, grãos ou cristais de um sólido é relativamente considerável em relação ao comprimento do microdispositivo. Nesses casos a teoria clássica dos meios contínuos não descreve apropriadamente a solicitação estrutural e é necessária uma abordagem mais geral através de teorias generalizadas não-clássicas que contém a elasticidade clássica como um caso particular delas, onde os parâmetros constitutivos que representam às partículas são desprezíveis. Quando os efeitos microestruturais são importantes, o comportamento não responde como um material homogêneo se não como um material homogêneo. Cem anos atrás os irmãos Cosserat desenvolveram uma teoria de grãos rígidos imersos dentro de um macromeio elástico; posteriormente Toupin, Mindlin e outros pesquisadores na década de 60 formularam a chamada teoria gradiente de deformações, que recentemente é um objeto de muitas investigações analíticas e experimentais. Na década de oitenta, Aifantis e colaboradores conseguiram desenvolver uma teoria de gradiente de deformações simplificada, baseada em só uma constante elástica adicional não-clássica representativa da energia de deformação volumétrica para caracterizar satisfatoriamente os padrões dos fenômenos não-clássicos. Beskos e colaboradores estenderam o campo de aplicações da proposta inicial de Aifantis e fizeram as primeira implementações de elementos de contorno 2D e 3D para análises de elasticidade gradiente estática, no domínio da frequência e a mecânica da fratura. Desde o tempo de Toupin e Mindlin, procura-se estabelecer uma base variacional da teoria e uma formulação consistente das condições de contorno cinemáticas e de equilíbrio, o que parece ter tido êxito com os recentes trabalhos de Amanatidou e Aravas. Esta tese apresenta a formulação do método híbrido de elementos de contorno e finitos na elasticidade gradiente desenvolvida por Dumont e Huamán decompondo o potencial de Hellinger-Reissner em dois princípios de trabalhos virtuais: o primeiro em deslocamentos virtuais e o segundo em forças virtuais. Com esta finalidade é considerado além dos parâmetros clássicos, o trabalho realizado pelas tensões, deformações, forças e deslocamentos não-clássicos. É apresentado o desenvoltimento das soluções fundamentais singulares e polinomiais atráves das equações diferenciais de sexta ordem obtidas da equação de equilíbrio em termos de deslocamento na elasticidade gradiente. É apresentada também a aplicaçõ do método híbrido de contorno para problemas de tensão axial unidimensional e flexão bidimensional de vigas. Finalmente mostra-se a aplicação numérica do método em elementos finitos, é verificado o patch test de elementos finitos de diferentes ordem e mostra-se também análises de convergência. / [en] The use of new mathematical modeling in the study of micro and Nano electro mechanical systems is currently becoming widespread. The scaling problem is apparent when the length of molecules, particles or grains immersed in the material is relatively important compared with the whole micro device dimension. Under this approach the classical theories of mechanics cannot describe suitably the structural requirement and it is necessary a more general outlook through non classical generalized theories which enclose the classical elasticity as a particular case where the non-classical constitutive parameters are negligible. When the microstructural effects are important, the material does not respond as a homogeneous but as a non-homogeneous one. A hundred years ago Cosserat brothers formulated a new theory of rigid grains which were embedded in an elastic macro medium; later Toupin, Mindlin along others researchers in 1960s developed a gradient strain theory which has been recently the source of many analystics and experimental investigations. In 1980s Ainfantis et al could develop a simplified strain gradient theory with just one additional non classical elastic constant which represents the volumetric elastic strain energy and characterized successfully the whole non classical pattern phenomenon. Beskos et al extended the treatment proposed initially by Aifantis and developed the first numerical applications for 2D and 3D boundary element methods and solved static as dynamic and crack problems. Since the times of Toupin and Mindlin it is looking for to establish a variational theory with a consistent cinematic and equilibrium boundary conditions, which seemed to have had success in the recent works of Amanatiodou and Aravas. This work presents the formulation of the hybrid boundary and finite element methods under the strain gradient scope which were developed by Dumont and Huamán through the versatile decomposition of the Hellinger-Reissner potential in two work principles: the displacements virtual work and the forces virtual work; both principles contain the virtual work performed by the non-classical magnitudes. Following, it is presented the complete development of singular and polynominal fundamental solutions abtained through the sixth order strain gradient differential equilibrium equations in terms of displacements. Next it is shown an application of the method to unidimensional truss element and bidimensional beam. Finally, it is presented a numerical application to strain gradient finite element, it is checked the patch tests to different elements orders and it is also shown a series of convergence analysis.

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