4,377 research outputs found
Thermal inactivation of Byssochlamys nivea in pineapple nectar combined with preliminary high pressure treatments
Byssochlamys nivea is a thermal resistant filamentous fungi and potential micotoxin producer. Recent studies have verified the presence of ascospores of such microorganism in samples of pineapple nectars. Although the majority of filamentous fungi have limited heat resistance and are easily destroyed by heat, Byssochlamys nivea ascospores have shown high thermal resistance. The aim of this work was to evaluate the application of linear and Weibull models on thermal inactivation (70, 80 and 90ºC) of Byssochlamys nivea ascospores in pineapple nectar after pretreatment with high pressure (550MPa or 650MPa during 15min). Following the treatments, survival curves were built up for each processing temperature and adjusted for both models. It was observed that survival curves at 90°C after high pressure pretreatment at 550 MPa/15 min did not fit well to linear and Weibull models. For all the other treatments, the Weibull model presented a better fit. At 90ºC without pressure treatment, the Weibull model also showed a better adjustment, having a larger R2 and a smaller RMSE. Regarding the process effectiveness, a 5-log reduction (t5), as recommended for pasteurization, was only achieved for Byssochlamys nivea ascospores presented in pineapple nectar at 90ºC/10.7 min with previous high pressure treatment of 650 MPa for 15 min. Considering the high intensity and energy demanding process with possibly product damage, other preventive and alternative treatments are being investigated
The early days of pandemic (H1N1) 2009 virus infection in the central region of Portugal
BACKGROUND: The first case of pandemic (H1N1) 2009 virus infection was diagnosed in the central region of Portugal on June 16, 2009, in a woman infected in Canada.
METHODS: The aim of our study was, first to characterize the clinical and epidemiologic aspects of all the patients with clinical manifestations included in the definition of case for investigation with samples submitted to diagnosis of the pandemic (H1N1) 2009 virus infection, in the central region of Portugal; second to assess the precision of the case definition of case for investigation considered in the study according to the presence or the absence of fever at the moment of clinical observation. We reviewed the medical records of all the patients presenting with Influenza like-illness classified as case for investigation and the first cases of patients infected with the new pandemic (H1N1) 2009 virus, diagnosed in the central region of Portugal during the pandemic period between June and August, 2009, were analyzed. Real-time reverse-transcriptase polymerase-chain-reaction (RT-PCR) testing was used to confirm the pandemic (H1N1) 2009 virus infection. Data collection was performed on a standardized paper format in agreement with the General Health Directorate. Results and discussion: Pandemic (H1N1) 2009 virus infection was confirmed in 255 patients. Overall, median age was 23 years and 42.7 % were included in the category of 20 to 29 years. Confirmed infection in patients with less than 2 years or greater than 50 years was a rare event. The first cases were imported from Europe, namely France, Spain and England. On a second phase, pandemic (H1N1) 2009 virus infection was acquired in the south of Portugal (Algarve), before de diagnosis of the first domestic case. The incidence rate for pandemic (H1N1) 2009 virus infection was 10.7 per 100,000 persons and was different according to the district. It was higher in the district of Coimbra and Guarda were the main roads connecting to Europe are. The median calculated incubation period for the for pandemic (H1N1) 2009 virus infection was 2 days. The length of the clinical manifestations until the patients look for medical observation had a median time of 2 days. All the cases were of mild to moderate severity. No deaths were observed.
CONCLUSIONS: The early days of pandemic (H1N1) 2009 virus infection was mild in our region. Most affected patients were young adults, with the extreme categories ages of life being spared. Early detection and diagnosis, combined with stringent isolation and treatment procedures could have slowed the spread of the infection in our region
Acaricidal activity of palm oil on Aceria guerreronis (Acari:Eriophyidae) and a nontarget predator.
The coconut mite,Aceria guerreronisKeifer (Acari: Eriophyidae), is a severe andubiquitous pest of coconut plantations worldwide. Vegetable oils contain fatty acids that areactive against a variety of agricultural pests; however, little is known about their efficiency incontrollingA. guerreronisas well as their adverse effects on its natural enemies. Here, weassessed the chemical profile of palm oil as well as its toxicity and repellence to bothA.guerreronisandTyphlodromus ornatusDenmark and Muma (Acari: Phytoseiidae), a naturalenemy of the pest. Oleic, palmitic, and linoleic acids accounted for over 85% of palm oil fattyacid composition. Also, palm oil was approximately 4-fold more toxic to the coconut mite thanto its predator. Furthermore, the lethal concentration percentage (LC)50and LC99of palm oilindicated greater activity against the coconut mite than to its predator. Therefore, by exhibitinghigher toxicity and repellence to the coconut mite, with substantial selectivity to the predatorT.ornatus, palm oil is a promising tool to be integrated in the control ofA. guerreronisin coconutplantations
The early days of pandemic (H1N1) 2009 virus infection in the central region of Portugal
BACKGROUND: The first case of pandemic (H1N1) 2009 virus infection was diagnosed in the central region of Portugal on June 16, 2009, in a woman infected in Canada.
METHODS: The aim of our study was, first to characterize the clinical and epidemiologic aspects of all the patients with clinical manifestations included in the definition of case for investigation with samples submitted to diagnosis of the pandemic (H1N1) 2009 virus infection, in the central region of Portugal; second to assess the precision of the case definition of case for investigation considered in the study according to the presence or the absence of fever at the moment of clinical observation. We reviewed the medical records of all the patients presenting with Influenza like-illness classified as case for investigation and the first cases of patients infected with the new pandemic (H1N1) 2009 virus, diagnosed in the central region of Portugal during the pandemic period between June and August, 2009, were analyzed. Real-time reverse-transcriptase polymerase-chain-reaction (RT-PCR) testing was used to confirm the pandemic (H1N1) 2009 virus infection. Data collection was performed on a standardized paper format in agreement with the General Health Directorate. Results and discussion: Pandemic (H1N1) 2009 virus infection was confirmed in 255 patients. Overall, median age was 23 years and 42.7 % were included in the category of 20 to 29 years. Confirmed infection in patients with less than 2 years or greater than 50 years was a rare event. The first cases were imported from Europe, namely France, Spain and England. On a second phase, pandemic (H1N1) 2009 virus infection was acquired in the south of Portugal (Algarve), before de diagnosis of the first domestic case. The incidence rate for pandemic (H1N1) 2009 virus infection was 10.7 per 100,000 persons and was different according to the district. It was higher in the district of Coimbra and Guarda were the main roads connecting to Europe are. The median calculated incubation period for the for pandemic (H1N1) 2009 virus infection was 2 days. The length of the clinical manifestations until the patients look for medical observation had a median time of 2 days. All the cases were of mild to moderate severity. No deaths were observed.
CONCLUSIONS: The early days of pandemic (H1N1) 2009 virus infection was mild in our region. Most affected patients were young adults, with the extreme categories ages of life being spared. Early detection and diagnosis, combined with stringent isolation and treatment procedures could have slowed the spread of the infection in our region
Flexible and structural coloured composite films from cellulose nanocrystals/hydroxypropyl cellulose lyotropic suspensions
FEDER funds through the COMPETE 2020 Program, National Funds through FCT -Portuguese Foundation for Science and Technology and POR Lisboa2020, PTDC/CTM-BIO/6178/2014, M-ERA-NET2/0007/2016 (CellColor) and PTDC/CTM-REF/30529/2017 (NanoCell2SEC).Lyotropic colloidal aqueous suspensions of cellulose nanocrystals (CNCs) can, after solvent evaporation, retain their chiral nematic arrangement. As water is removed the pitch value of the suspension decreases and structural colour-generating films, which are mechanically brittle in nature, can be obtained. Increasing their flexibility while keeping the chiral nematic structure and biocompatible nature is a challenging task. However, if achievable, this will promote their use in new and interesting applications. In this study, we report on the addition of different amounts of hydroxypropyl cellulose (HPC) to CNCs suspension within the coexistence of the isotropic-anisotropic phases and infer the influence of this cellulosic derivative on the properties of the obtained solid films. It was possible to add 50 wt.% of HPC to a CNCs aqueous suspension (to obtain a 50/50 solids ratio) without disrupting the LC phase of CNCs and maintaining a left-handed helical structure in the obtained films. When 30 wt.% of HPC was added to the suspension of CNCs, a strong colouration in the film was still observed. This colour shifts to the near-infrared region as the HPC content in the colloidal suspension increases to 40 wt.% or 50 wt.% The all-cellulosic composite films present an increase in the maximum strain as the concentration of HPC increases, as shown by the bending experiments and an improvement in their thermal properties.publishersversionpublishe
Análise de repetições em dados biológicos
The decoding of the genomes has created new challenges on the scientific community linked to the area of computation and information technologies. Daily, new data is added to numerous databases with billions of records, coming from more advanced equipment, helping in decoding the genomes. Determine how important and relevant are these data in order to find value-added information and obviously turn them into knowledge,is the main challenge for the bioinformatics research community. The analysis of genomes and proteomes of several organisms allow us to observe the behaviour at the evolution of species. In this study, our focus goes to a particular aspect of this analysis: the repetition of some codons and their amino acids inside several orthologous genes in eukaryotic organisms. Belonging to different stages of evolution, the main objective focuses on achieving results on the evolution of these repetitions over millions of years. We now know that these repetitions in humans are the source of several neurodegenerative diseases among others. This analysis will verify the conservation or repression, of these repetitions throughout the process of speciation as well at the level of relationship that may exist between these repetitions and those diseases. For this study we have developed an algorithm for A descodificação dos genomas veio criar novos desafios na comunidade científica ligada à área da computação e da informática. Diariamente são alimentadas inúmeras bases de dados com biliões de registos provenientes de equipamentos cada vez mais evoluídos, que auxiliam na descodificação dos genomas. Determinar o quão importante e relevante são esses dados, de forma a retirar valor acrescentado – informação, e obviamente transformá-los em conhecimento, é o grande desafio actual para a comunidade de investigadores de bioinformática. A análise de genomas, bem como dos proteomas dos vários organismos permitem-nos observar o comportamento ao nível da evolução das espécies. Neste estudo focamos a atenção num aspecto particular dessa análise: as repetições de determinados codões e dos respectivos aminoácidos nos vários organismos eucariotas, especificamente em genes ortólogos. Pertencente a várias fases da evolução das espécies, o objectivo principal centra-se na obtenção de resultados quanto à evolução dessas repetições ao longo de milhões de anos. Sabemos hoje que essas repetições no ser humano são a causa de diversas doenças neuro-degenerativas, entre outras, pelo que esta análise permitirá verificar o estado de conservação ou repressão, dessas repetições ao longo do processo de especiação, bem como ao nível do relacionamento que poderá existir entre essas repetições e as doenças nos seres superiormente evoluídos. Para este estudo foi desenvolvido um algoritmo de detecção de padrões de repetição, que possibilita uma análise detalhada da localização de uma determinada sequência, bem como das sequências que melhor se ajustam ao padrão de repetição inicial.Centro de Estudos em Educação, Tecnologias e Saúd
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