Study of the prevalence and clinical features of food allergies in adults and adolescents from Beira Interior

Background: Food allergy is an important health problem in western-style countries, and its prevalence has increased in the last three decades. Studies of the prevalence of food allergy in the general population in Portugal are scarce. Thus, the objectives of the present thesis were: a) to design and validate a food allergy study questionnaire for Portuguese adults, b) to determine the prevalence, and clinical characteristics of food allergy in a population of adolescents and adults in Beira Interior, and c) to determine the prevalence, and clinical characteristics of food allergy in the elderly population worldwide by conducting a systematic review of the bibliography and a subsequent meta-analysis of the data. Methods: A 17-item questionnaire was developed and applied by phone to a group of food allergy patients and a group of healthy individuals, with subsequent reassessment (re-test). Face and content validity, intelligibility, construct validity, and test-retest reliability (temporal stability) were analysed. This tool, once validated, was applied in two population-based individuals samples (3,168 adolescents; mean age: 14.3±1.1; 51.7% female; 1.436 adults; mean age of 47 years, median age: 45 years, 50.6% female), registered at participating Healthcare cross-sectional studies performed in various healthcare centres and secondary schools from central Portugal. All randomly selected individuals (1702 adolescents; mean age: 14.9±2.1 years; median age: 14 years; 61.9% female; 840 adults; (mean age: 48 years, median age: 46 years, 51.3% female) replied to the food allergy questionnaire by phone (adults) or in a written form (adolescents). Those who reported an adverse food reaction were invited to come to the hospital, where clinical history was taken, skin prick (SPT) and prick-prick skin (SPPT) tests were performed and food allergen-specific IgE levels (sIgE) were determined. An open oral challenge was performed in selected cases. Cases of positive clinical history of immediate (up to 2 hours after ingestion) reaction in association with positive food sIgE levels and/or skin prick tests were classified as IgE-associated probable food allergy. Cases of positive clinical history of delayed (more than 2 hours after ingestion) and negative food sIgE levels independently of positive SPT or SPPT results were classified as non-IgE associated probable food allergy. A systematic review and meta-analysis on the prevalence and risk factors for food allergy in elderly individuals were conducted. A searched of international electronic databases including MEDLINE, EMBASE, Cochrane Library, CINAHL, AMED and ISI Web of Science, as well as clinical trials databases for published, unpublished and on-going studies from 1980 to 2019. There were no restrictions on the language or geography of publication. The Critical Appraisal Skills Programme (CASP) quality assessment tool was used to appraise the methodological quality of the included studies. A descriptive summary with data tables was elaborated, and when clinically relevant and statistically adequate, a meta-analysis using random-effects modelling was carried out, given the expected clinical, methodological and statistical heterogeneity of the selected studies. The PRISMA checklist guided the reporting of the systematic review. Results: Face and content validity of the questionnaire allowed item reduction from 30 to 17 items with adequate content validity index > 0.78. Construct validity was confirmed in a group of 66 confirmed food allergic patients. Test-Retest Reliability (general temporal stability) of the test had a Spearman correlation coefficient value of 0.845 for the retest. Cohen's Kappa values for the relevant questions were greater than 0.890 for almost all items. No differences were found when sex, age and volunteers’ recruitment origin were analysed. An inverse relationship was found between reliability and retest time interval. The prevalence of probable food allergy in our sample was 1.41% in adolescents and 1% in adults, with fresh fruits and shellfish in adolescents and shellfish and fish in adults as the most frequently implicated foods. IgE-mediated probable food allergy occurred in 1.23% of adolescent and in 0.71% of adult cases, and fresh fruits and shellfish in adolescents and shellfish and peanut in adults were the foodstuffs mainly involved. Cutaneous symptoms were most frequently reported and prevalence values and food types were discrepant between self-reported and probable food allergies in both populations. The prevalence of food allergy in the elderly was 6.46% for self-report, slightly lower than that of SR + food-specific IgE levels (6.95%) and SR + SPT (1.30%). In addition, it was lower than that in non-elderly adults, but higher than in children assessed by self-report outcomes. Finally, it was lower when compared with the other age groups when self-report symptoms were combined with in vitro or in vivo outcome assessment. No results were obtained regarding time and geographical trends, predominant foods, risk and prognostic factors, and clinical manifestations of food allergy in the elderly. There was great heterogeneity both in the systematic review and the meta-analysis, which was lowest for shellfish (I2=0.000%) and highest for fruits (I2=98.205%). Conclusions: Due to the quick and easy implementation, confirmation of face, content and construct validity as well as high temporal reproducibility, the screening questionnaire was a useful study tool for an initial approach to detection of food allergies in adults. The prevalence of probable food allergies in Portuguese adolescents and adults was low, mostly related to fresh fruits, shellfish, nuts and peanut in the former, and to shellfish, fish, peanut and nuts in the latter. Most cases frequently involved cutaneous symptoms. The systematic review allowed us to draw up-to-date estimates of the prevalence of adverse food reactions in elderly individuals, worldwide. However, most of the studies were not focused on the population over 60 years of age, which resulted in an evident lack of information and biases that might affect exposure and outcomes. This fact conditioned the knowledge of the clinical characteristics, implicated foods, evolution and diagnosis of food allergy in these individuals, as well as the development of possible preventative measures focused specifically on the elderly population.Introdução: As reacções adversas alimentares, entre as quais está incluída a alergia alimentar, são um importante problema de saúde pública no Mundo Ocidental, tendo-se registado um aumento da sua prevalência durante os últimos trinta anos. Embora estas reacções não tenham a magnitude de outras doenças alérgicas, é certo que têm uma importante repercussão na qualidade de vida dos doentes, condicionando-lhes certas restrições alimentares, assim como situações de stress emocional e dificuldade para a sua integração social. Apesar de existirem vários estudos de base populacional em diferentes regiões do mundo, existem muitos poucos estudos sobre a prevalência populacional de alergia alimentar em Portugal: apenas um estudo em crianças entre os 3 e os 11 anos e outro um inquérito telefónico em uma pequena amostra de adultos. Outras lacunas são de salientar. Em primeiro lugar, é importante realçar que não existe um questionário específico em idioma português para o rastreio deste tipo de patologias. Em segundo lugar, o notável aumento da população idosa, com mais de 60 anos de idade (de acordo com a definição da OMS) a nível mundial, não tem sido acompanhado por estudos focados na alergia alimentar, sendo estes muitos escassos. Quando existem, os dados sobre idosos estão frequentemente englobados dentro dos estudos realizados em adultos, sem diferenciação, o que dificulta o adequado conhecimento do impacto desta patologia nos idosos. Assim, os objectivos da presente tese são: a) Desenhar e validar um questionário específico para o rastreio de alergia alimentar em adultos, b) determinar a prevalência e as características clínicas da alergia alimentar em uma população de adolescentes e adultos residentes na Beira Interior e c) determinar a prevalência e características clínicas da alergia alimentar na população de idosos a escala mundial, através da realização de uma revisão bibliográfica sistemática e uma posterior meta-análise dos dados. Métodos: Para a validação do questionário, foi realizado um estudo multicêntrico transversal em uma amostra randomizada simples de 126 adultos entre 18 e 82 anos (66 deles com diagnóstico prévio confirmado de alergia alimentar por prova de provocação oral e 60 voluntários saudáveis), residentes na região da Beira Interior – Centro de Portugal. A esta amostra foi aplicado telefonicamente um questionário, em idioma português, de 17 questões para o rastreio de alergia alimentar em duas fases (teste e reteste). Foram analisadas a validade aparente (ou facial) e de conteúdo, a inteligibilidade, a validade conceptual e a fiabilidade teste-reteste (estabilidade temporal) desta ferramenta. O questionário foi aplicado após a sua validação a duas amostras populacionais de indivíduos residentes na Beira Interior (3168 adolescentes: média de idade de 14,3±1,1 anos; 51,7% deles raparigas e 1436 adultos: média de idade de 47 anos, mediana de 45 anos, 50,6% mulheres), registados nas escolas secundárias e nos Centros de Saúde participantes. O questionário foi respondido por 1702 adolescentes (média de idade de 14,9±2,1 anos; mediana de 14 anos; 61,9% raparigas) e 840 adultos (média de idade de 48 anos; mediana de 46 anos, 51,3% mulheres), por via telefónica (adultos), ou por escrito (adolescentes). Os indivíduos que reportaram a existência de uma reacção adversa alimentar foram referenciados para uma unidade hospitalar, onde foi realizada uma história clínica específica, testes cutâneos (por picada - SPT e por dupla picada, com alimentos in natura - SPPT) e determinação de IgE específica para alergénios alimentares (sIgE). Nos casos onde existia dúvida diagnóstica foi realizada uma prova de provocação oral aberta com alimento. Os casos com história clínica positiva de uma reacção imediata (até 2 horas após a ingestão do alimento) em associação com resultados positivos de IgE específica para alergénios alimentares e/ou testes cutâneos, foram considerados como alergia alimentar provável, mediada por IgE. Os casos em que existiu uma história clínica positiva de uma reacção retardada (mais de 2 horas após a ingestão do alimento) e resultados negativos de IgE específica para alergénios alimentares, independentemente do resultado dos testes cutâneos, foram considerados como alergia alimentar provável não mediada por IgE. Para abordar o objectivo de análise da prevalência e factores de risco para alergias alimentares em idosos, foi realizada uma revisão sistemática e uma meta-análise acerca da prevalência e características clínicas da alergia alimentar em indivíduos com mais de 60 anos de idade, a nível mundial, em várias bases de dados electrónicas (MEDLINE, EMBASE, Cochrane Library, CINAHL, AMED e ISI Web of Science), assim como diversas bases de dados de ensaios clínicos publicados, não publicados e em fase de desenvolvimento desde 1980 até 2019. A pesquisa bibliográfica não teve restrição idiomática nem geográfica. Foi utilizado o programa Critical Appraisal Skills Programme (CASP) como ferramenta para a avaliação da qualidade metodológica dos estudos incluídos. Os dados obtidos foram mostrados de maneira sumária em forma de tabelas. Foi realizada uma meta-análise utilizando um modelo de efeitos aleatórios com os dados clinica e metodologicamente adequados desde o ponto de vista estatístico. A lista de verificação PRISMA dirigiu o processo da revisão sistemática. Resultados: A análise da validade aparente e de conteúdo do questionário, conduziram à redução de 30 para 17 itens com um índice de consistência interna superior a 0,78. A validade conceptual foi assegurada num grupo de 66 pacientes com alergia alimentar confirmada. A fiabilidade teste-reteste (estabilidade temporal geral) do teste apresentou um coeficiente de correlação de Spearman do 0,845 para o reteste. Os valores associados ao teste Kappa de Cohen para as questões relevantes foram superiores a 0,890 para quase todos os itens. Não foram encontradas diferenças em função do sexo, idade nem procedência dos voluntários. Contudo, detetou-se uma relação inversa entre a fiabilidade e o intervalo temporal do reteste. A prevalência de alergia alimentar autorreportada na nossa amostra populacional foi de 11% em adolescentes e de 6% em adultos, sendo os frutos frescos, mariscos e leite os alimentos mais frequentemente implicados nas reacções apresentadas pelos adolescentes, e os mariscos, frutas frescos e peixe nos adultos. Após a finalização do estudo alergológico, a prevalência de alergia alimentar provável na nossa amostra populacional baixou para 1,41% nos adolescentes e para 1,0% nos adultos. Os alimentos mais frequentemente implicados foram os frutos frescos, marisco e frutos secos nos adolescentes, e os mariscos, peixe e amendoim/frutos secos nos adultos. Foi identificado um mecanismo mediado pela IgE em 1,23% dos adolescentes e em 0,71% dos adultos, sendo os frutos frescos e mariscos nos adolescentes, e marisco e amendoim nos adultos, os alimentos mais frequentemente envolvidos nestes casos. A sintomatologia mais frequentemente apresentada foi a cutânea. Foi encontrada uma discrepância em ambas as populações, em termos dos valores da prevalência e tipo de alimentos implicados encontrados durante fase do autorreporte e os obtidos após a finalização do estudo alergológico completo, sendo os valores de prevalência sempre superiores quando baseados no autorreporte. A prevalência de alergia alimentar autorreportada na população idosa foi de 6,46%, discretamente menor do que quando associada à determinação dos níveis de IgE específica para alergénios alimentares (6,95%), mas superior à observada quando baseada em testes cutâneos (1,30%). Os valores encontrados nos estudos efectuados por autorreporte foram inferiores aos dos adultos não-idosos, mas superiores aos das crianças. Finalmente, a população idosa apresentou, nos estudos que combinaram o autorreporte com outros métodos de diagnóstico in vitro ou in vivo, valores da prevalência de alergia alimentar menores do que nos observados nos outros grupos etários. Não foram identificadas associações entre os tipos de alimentos implicados, sintomatologia relacionada, temporalidade de aparecimento dos sintomas, distribuição geográfica, factores de risco ou de prognóstico na população idosa com alergia alimentar. Foi observada uma grande heterogeneidade entre os estudos considerados, quer na revisão sistemática, quer na meta-análise. Esta heterogeneidade foi menor nos artigos que estudaram a alergia ao marisco (I2=0,000%) e maior naqueles que estudaram a alergia aos frutos frescos (I2=98,205%). Conclusões: Como resultado da sua simples e rápida aplicabilidade, confirmação da sua validade aparente, conceptual e de conteúdo, assim como da sua elevada estabilidade temporal, o questionário desenhado demonstrou ser uma eficaz ferramenta numa primeira abordagem para o rastreio e identificação da alergia alimentar em adultos e que pode ser aplicado, com as devidas adaptações relacionadas com a dieta e costumes locais, em outros países de língua oficial portuguesa. A prevalência da alergia alimentar provável na nossa amostra de adolescentes e adultos portugueses foi baixa, principalmente relacionada com a ingestão de frutos frescos, mariscos, frutos secos e amendoim nos primeiros e com mariscos, peixe e frutos secos nos segundos. Estes resultados confirmam que os alimentos implicados são similares aos referidos em outros estudos realizados com similar metodologia em outros países da área Mediterrânica, com similar cultura e alimentação. O nosso estudo confirmou a relação inversa entre os valores de prevalência de alergia alimentar e o grau de exigência do diagnóstico alergológico. Por outro lado, foi dos escassos trabalhos a nível mundial que descreveram as características clínicas da alergia alimentar numa determinada população geral, sendo o primeiro destas características em Portugal. A realização da revisão sistemática permitiu realizar uma estimativa actualizada da prevalência das reacções adversas alimentares na população idosa a nível mundial. A maior parte dos estudos existentes sobre esta temática não estão focados na população maior de 60 anos de idade, resultando numa evidente falta de informação que enviesa os nossos resultados. Esta situação condiciona o correto conhecimento das características clínicas, alimentos implicados, evolução e diagnóstico da alergia alimentar nesta faixa etária. Em termos futuros, para uma determinação mais exacta da prevalência real da alergia alimentar na população portuguesa nas suas várias faixas etárias (adolescentes, adultos e idosos), será fundamental implementar efectuar um estudo multicéntrico mais alargado, que envolva unidades de saúde de todo o País. Mais ainda, será fundamental conseguir-se efectuar o estudo de forma completa, recorrendo, sempre que adequado, a provocações orais duplamente cegas, Esta abordagem, com detecção de números mais alargados de doentes com alergias alimentares, poderá também permitir avaliar a eventual existencia de fenótipos clínicos diferentes de alergias alimentares nos três grupos etários. Mais ainda, implicará a realização do primeiro estudo mundial sobre alergias alimentares em idosos. Por outro lado, a estabilidade de eventuais fenótipos de alergias alimentares poderá será avaliada num estudo longitudinal. Assim, através destas e outras abordagens, poderemos comprender melhor o impacto atual da alergia alimentar e propor uma estratégia diagnóstica, terapêutica e preventiva, se possível, nesta área

Optimization of Architectural Thermal Envelope Parameters in Modern Single-Family House Typologies in Southeastern Spain to Improve Energy Efficiency in a Dry Mediterranean Climate

The increasing regulatory requirements for energy efficiency in Europe imply a significant increase in insulation and solar control of buildings, especially in hot and semi-arid climates with high annual insolation such as the Spanish Mediterranean southeast. The consequences in architectural design to optimize compliance with the new technical and regulatory requirements of nearly zero-energy buildings are high. This paper analyzes the energy performance of a modern single-family house on the Spanish Mediterranean coast. The objective is to determine which design parameters most influence the energy improvement of this case study in order to establish design strategies that can be generalized to other new construction or energy retrofit projects, taking into account the specific characteristics of the warm and semi-arid Mediterranean climate. The scientific novelty of the work is to demonstrate that the design criteria of most modern single-family houses built or rehabilitated in the Spanish Mediterranean in the last decade comply with the energy efficiency requirements of Directive 2010/31/EU but are not specifically adapted and optimized for the special characteristics of the dry Mediterranean climate. This is the case of the house studied in this paper. The methodology used consisted of a systematized study of the main construction and geometric parameters that most influence the thermal calculation of this project: the thermal insulation thickness, thermal transmittance of the glazing, solar control of the glazing, total solar energy transmittance of the glazing with the movable shading device activated, size of glazing and the size of façade overhangs. The results obtained show that the use of mobile solar protection devices in summer, such as awnings or blinds, reduces the cooling need in summer up to 44% and the overall annual energy need (Cooling + Heating) up to 20%. This implementation is more efficient than increasing the thermal insulation of facades and glazing, reducing the size of windows or increasing overhangs. The most optimal solution is the simultaneous modification of several parameters. This reduces both heating need in winter and cooling need in summer, achieving an overall reduction in an annual need of 48%. This multiple solution improves the annual energy performance of the house much more than any solution consisting of modifying a single individual parameter. The results determine trends, explanations and deductions that can be extrapolated to other projects

Exploring Energy Retrofitting Strategies and Their Effect on Comfort in a Vernacular Building in a Dry Mediterranean Climate

This research explores the energy behaviour of a traditional house on the Mediterranean coast of south-eastern Spain. The objective of the work is to determine the optimal passive strategies for rehabilitating a traditional house, improving its energy savings and comfort, considering the characteristics of the warm semi-arid Mediterranean climate. The main novelty of this article is that it demonstrates that the limits imposed by current regulations, based on globalised climate strategy approaches, undermine the energy efficiency capacity that passive solutions in vernacular architecture already employed. The methodology used consists of a systematised multi-objective study of various energy rehabilitation strategies. Four strategies were studied: raising the thermal insulation of enclosures, improving thermal insulation and solar control glazing with movable shading devices, increasing the size of windows and introducing the use of natural ventilation enhanced by ceiling fans. The results show that simultaneous improvement of these parameters reduces cooling and heating requirements by up to 87%, reducing the energy consumption of air conditioning systems. Indoor temperatures are also maintained within the comfort limits set by regulations for 91% of hours per year without the need for air conditioning systems. This results in a passive energy-efficient and comfortable house almost all year round. This work offers an alternative solution to the comfort standards of current Spanish regulations and demonstrates the need to adapt Fanger’s analytical method for comfort estimation. The research concludes that the comfort criteria of current energy regulations should be modified to better adapt the design criteria to the dry Mediterranean climate.This research received an external grant from the Colegio Territorial de Arquitectos de Alicante (CTAA)

Development of a screening questionnaire for the study of food allergy in adults

Background & aims: As far as we know, no screening questionnaire has been developed and validated for identification of adverse food reactions in Portuguese-speaking adults, as an initial approach towards the investigation of cases of possible food allergy. Thus, the objective of this study was to develop and validate a screening questionnaire of food allergy in adult Portuguesespeaking patients. Methods: This was a multicentre, cross-sectional study using a simple random sample of 186 adults between 18 and 82 years old from various parts of the centre of Portugal. Intelligibility of the questionnaire was first assessed in 24 patients with confirmed IgE- or non-IgE-mediated food allergy, and in 24 volunteers without food allergies. The 17-item questionnaire was subsequently applied by phone to 78 food allergic patients (66 IgE-mediated and 12 non-IgE mediated) and to 60 non-food allergic volunteers, with subsequent reassessment (re-test). Face and content validity, intelligibility, construct validity, and test-retest reliability (temporal stability) were analysed. Results: Face and content validity allowed item reduction from 30 to 17 items with adequate content validity index >0.78. Construct validity was confirmed in the 66 confirmed IgE-mediated food allergic patients, 12 non-IgE-mediated food allergic patients, and 60 non-allergic patients. Test-Retest Reliability (general temporal stability) of the test had a Spearman correlation coefficient value of 0.845 for the retest. Cohen's Kappa values for the relevant questions were greater than 0.890 for almost all items. No differences were found when sex, age, and volunteers' recruitment origin were analysed. An inverse relationship was found between reliability and retest time interval. Conclusions: Due to the quick and easy implementation, confirmation of face, content and construct validity as well as high temporal reproducibility, this screening questionnaire may be a useful study tool for an initial approach to detection of food allergies in adults.info:eu-repo/semantics/publishedVersio

Permeable frontiers in the open sea: The case of Swordfish in the Atlantic Ocean

There is a vivid debate about the border location between North and South Atlantic swordfish stocks. Climate oscillations, East Atlantic (EA) and North Atlantic Oscillation (NAO), have a major impact on the Northern Hemisphere climate and weather conditions. The initial hypothesis of present study was that if it is considering the southern frontier, each stock will be differentially affected by both climatic oscillations, which would imply the existence of a strong border. However, a similar effect on both sides of the border would result in a permeable barrier. The results suggest that the combined effects of EA and NAO affect both the North and the South Atlantic swordfish stocks in similar ways, and consequently, the location of the border may reside farther north than the current management boundary at 5°N.Postprint0,60

Implementation of an intraoperative electron radiotherapy in vivo dosimetry program

Background: Intraoperative electron radiotherapy (IOERT) is a highly selective radiotherapy technique which aims to treat restricted anatomic volumes during oncological surgery and is now the subject of intense re-evaluation. In vivo dosimetry has been recommended for IOERT and has been identified as a risk-reduction intervention in the context of an IOERT risk analysis. Despite reports of fruitful experiences, information about in vivo dosimetry in intraoperative radiotherapy is somewhat scarce. Therefore, the aim of this paper is to report our experience in developing a program of in vivo dosimetry for IOERT, from both multidisciplinary and practical approaches, in a consistent patient series. We also report several current weaknesses. Methods: Reinforced TN-502RDM-H mobile metal oxide semico nductor field effect tran sistors (MOSFETs) and Gafchromic MD-55-2 films were used as a redundant in vivo treatment verification system with an Elekta Precise fixed linear accelerator for calibrations and tre atments. In vivo dosimetry was performed in 45 patients in cases involving primary tumors or relapses. The m ost frequent primary tumors were breast (37 %) and colorectal (29 %), and local recurrences among relapses was 83 %. We made 50 attempts to measure with MOSFETs and 48 attempts to measure with films in th e treatment zones. The surgical team placed both detectors with supervision from the radiation oncologist and following their instructions. Results: The program was considered an overall success by the different professionals involved. The absorbed doses measured with MOSFETs and films were 93.8 ± 6.7 % and 97.9 ± 9.0 % (mean ± SD ) respectively using a scale in which 90 % is the prescribed dose and 100 % is the maximum absorbed dose delivered by the beam. However, in 10 % of cases we experienced dosimetric problems due to detector misalignment, a situation which might be avoided with additional checks. The useful MOSFET lifetime length and the film sterilization procedure should also be controlled. Conclusions: It is feasible to establish an in vivo dosimetry program for a wide set of locations treated with IOERT using a multidisciplinary approach according to the skills of the professionals present and the detectors used; oncological surgeons ’ commitment is key to success in this context. Films are more unstable and show higher uncertainty than MOSFETs but are cheaper and are useful and convenient if real-time treatment monitoring is not necessary.This work was supported by grants IPT-300000-2010-3 and PI11/01659 from the Spanish Government and ERDF funds

Prevalence and risk factors for food allergy in older people: protocol for a systematic review

Studies suggest that the prevalence of food allergy may be increasing worldwide. Results regarding the prevalence and features of adverse food reactions older people have, however, scarcely been analysed in the literature. Thus, the objective of the present systematic review will be to describe the prevalence of food allergy in older individuals, its risk factors, clinical features, as well as the most frequently and commonly involved foods.info:eu-repo/semantics/publishedVersio

Prevalence and clinical features of adverse food reactions in Portuguese adolescents

Background & aims: The objective of the present study was to determine, for the first time, the prevalence and clinical features of food allergy in Portuguese adolescents. Methods: Cross-sectional study performed in various secondary schools in central Portugal. Randomly selected adolescents replied to a validated food allergy questionnaire. Those who reported an adverse food reaction were seen at participating hospitals, where clinical history was taken, skin prick (SPT) and prick-prick skin (SPPT) tests were performed, and food allergen-specific IgE levels (sIgE) were determined. An open oral challenge was performed in selected cases. Cases of positive clinical history of immediate (up to 2 h after ingestion) reaction in association with positive food sIgE levels and/or SPT were classified as IgE-associated probable food allergy and as confirmed IgE-mediated food allergy if food challenges were positive. Cases of positive clinical history of delayed (more than 2 h after ingestion) and negative food sIgE levels independently of positive SPT or SPPT results, were classified as non-IgE associated probable food allergy. Results: The prevalence of probable food allergy in Portuguese adolescents was 1.41% (95% CI: 0.90–2.03%), with fresh fruits, shellfish, nuts, and peanut as the most frequently implicated foods. IgE-mediated probable food allergy occurred in 1.23% (95% CI: 0.67–1.72%) of cases, with fresh fruits, shellfish, and nuts mainly involved. Cutaneous symptoms were most frequently reported. Conclusions: The prevalence of probable food allergies in Portuguese adolescents is low, is mostly related to fresh fruits, shellfish, nuts, and peanut, and most frequently involves cutaneous symptoms.info:eu-repo/semantics/publishedVersio

Sensor-Based Model Driven Control Strategy for Precision Irrigation

Improving the efficiency of the agricultural irrigation systems substantially contributes to sustainable water management. This improvement can be achieved through an automated irrigation system that includes a real-time control strategy based on the water, soil, and crop relationship. This paper presents a model driven control strategy applied to an irrigation system, in order to make an efficient use of water for large crop fields, that is, applying the correct amount of water in the correct place at the right moment. The proposed model uses a predictive algorithm that senses soil moisture and weather variables, to determine optimal amount of water required by the crop. This proposed approach is evaluated against a traditional irrigation system based on the empirical definition of time periods and against a basic soil moisture control system. Results indicate that the use of a model predictive control in an irrigation system achieves a higher efficiency and significantly reduce the water consumption

La Historia de Vida como técnica de recolección de datos cualitativos para estudios en Ciencias Sociales

The life story as a qualitative data collection technique and its contributions to social sciences is approached, through an analysis in order to determine its particular role in social sciences studies. This techinique provide a better comprehension of a person´s story based on experiences in and out of its context, by conceptualizing a vision that for an adequate study that implies direct interaction with persons. The life story is considered as a reliable technique for data collection, leading to remarkable results that deliver a relevant impact to social sciences studies.  Se aproxima a la historia de vida como técnica de recolección de datos cualitativa y sus aportaciones a las ciencias sociales, mediante un análisis para determinar su papel particular en estudios en ciencias sociales. Esta técnica brinda una mejor comprensión de la historia de una persona, basada en experiencias dentro y fuera de su contexto, conceptualizando una visión para un adecuado estudio que implica una interacción directa con personas. Se considera a la historia de la vida como una técnica confiable para recolectar datos que conduzcan a resultados notables que brinden un impacto relevante para los estudios en ciencias sociales