Modelação numérica de uma caldeira doméstica a pellets

A biomassa é uma das fontes de energia renovável com maior potencial em Portugal, sendo a capacidade de produção de pellets de biomassa atualmente instalada superior a 1 milhão de toneladas/ano. Contudo, a maioria desta produção destina-se à exportação ou à utilização em centrais térmicas a biomassa, cujo crescimento tem sido significativo nos últimos anos, prevendo-se que a capacidade instalada em 2020 seja de aproximadamente 250 MW. O mercado português de caldeiras a pellets é bastante diversificado. O estudo que realizamos permitiu concluir que cerca de 90% das caldeiras existentes no mercado português têm potências inferiores a 60 kW, possuindo na sua maioria grelha fixa (81%), com sistema de ignição eléctrica (92%) e alimentação superior do biocombustível sólido (94%). O objetivo do presente trabalho foi o desenvolvimento de um modelo para simulação de uma caldeira a pellets de biomassa, que para além de permitir otimizar o projeto e operação deste tipo de equipamento, permitisse avaliar as inovações tecnológicas nesta área. Para tal recorreu-se o BiomassGasificationFoam, um código recentemente publicado, e escrito para utilização com o OpenFOAM, uma ferramenta computacional de acesso livre, que permite a simulação dos processos de pirólise, gasificação e combustão de biomassa. Este código, que foi inicialmente desenvolvido para descrever o processo de gasificação na análise termogravimétrica de biomassa, foi por nós adaptado para considerar as reações de combustão em fase gasosa dos gases libertados durante a pirólise da biomassa (recorrendo para tal ao solver reactingFoam), e ter a possibilidade de realizar a ignição da biomassa, o que foi conseguido através de uma adaptação do código de ignição do XiFoam. O esquema de ignição da biomassa não se revelou adequado, pois verificou-se que a combustão parava sempre que a ignição era inativada, independentemente do tempo que ela estivesse ativa. Como alternativa, usaram-se outros dois esquemas para a combustão da biomassa: uma corrente de ar quente, e uma resistência de aquecimento. Ambos os esquemas funcionaram, mas nunca foi possível fazer com que a combustão fosse autossustentável. A análise dos resultados obtidos permitiu concluir que a extensão das reações de pirólise e de gasificação, que são ambas endotérmicas, é muito pequena, pelo que a quantidade de gases libertados é igualmente muito pequena, não sendo suficiente para libertar a energia necessária à combustão completa da biomassa de uma maneira sustentável. Para tentar ultrapassar esta dificuldade foram testadas várias alternativas, , que incluíram o uso de diferentes composições de biomassa, diferentes cinéticas, calores de reação, parâmetros de transferência de calor, velocidades do ar de alimentação, esquemas de resolução numérica do sistema de equações diferenciais, e diferentes parâmetros dos esquemas de resolução utilizados. Todas estas tentativas se revelaram infrutíferas. Este estudo permitiu concluir que o solver BiomassGasificationFoam, que foi desenvolvido para descrever o processo de gasificação de biomassa em meio inerte, e em que a biomassa é aquecida através de calor fornecido pelas paredes do reator, aparentemente não é adequado à descrição do processo de combustão da biomassa, em que a combustão deve ser autossustentável, e em que as reações de combustão em fase gasosa são importantes. Assim, é necessário um estudo mais aprofundado que permita adaptar este código à simulação do processo de combustão de sólidos porosos em leito fixo.

Salivary gland proteins of the human malaria vector, Anopheles dirus B (Diptera: Culicidae)

Salivary gland proteins of the human malaria vector, Anopheles dirus B were determined and analyzed. The amount of salivary gland proteins in mosquitoes aged between 3 - 10 days was approximately 1.08 ± 0.04 µg/female and 0.1 ± 0.05 µg/male. The salivary glands of both sexes displayed the same morphological organization as that of other anopheline mosquitoes. In females, apyrase accumulated in the distal regions, whereas alpha-glucosidase was found in the proximal region of the lateral lobes. This differential distribution of the analyzed enzymes reflects specialization of different regions for sugar and blood feeding. SDS-PAGE analysis revealed that at least seven major proteins were found in the female salivary glands, of which each morphological region contained different major proteins. Similar electrophoretic protein profiles were detected comparing unfed and blood-fed mosquitoes, suggesting that there is no specific protein induced by blood. Two-dimensional polyacrylamide gel analysis showed the most abundant salivary gland protein, with a molecular mass of approximately 35 kilodaltons and an isoelectric point of approximately 4.0. These results provide basic information that would lead to further study on the role of salivary proteins of An. dirus B in disease transmission and hematophagy.

IDENTIFICATION OF SANDFLIES (Diptera: Psychodidae: Phlebotominae) BLOOD MEALS IN AN ENDEMIC LEISHMANIASIS AREA IN BRAZIL

SUMMARY The aim of this study was to identify blood meals of female sandflies captured in the municipality of Governador Valadares, an endemic area of visceral and cutaneous leishmaniasis, in the State of Minas Gerais, Brazil. From May 2011 to January 2012, captures were performed using HP light traps in four districts. There were 2,614 specimens (2,090 males and 524 females) captured; 97 engorged females were identified belonging to the species Lutzomyia longipalpis (82.1%) and Lutzomyia cortelezzii (17.9%). Considering simple and mixed feeding, the enzyme-linked immunosorbent assay revealed a predominance of chicken blood (43.6%) in Lutzomyia longipalpis, showing the important role that chickens exert around the residential areas of Governador Valadares. This finding increases the chances of sandflies contact with other vertebrates and consequently the risk of leishmaniasis transmission.

Comparative biology of the two sister species of Triatominae (Hemiptera: Reduviidae)

INTRODUCTION: Triatoma pseudomaculata and T. wygodzinskyi (Hemiptera: Reduviidae: Triatominae) are two Brazilian vectors of Chagas disease. The first is an arboricolous species in sylvatic environment and considered a vector of T. cruzi in peridomestic structures; the second, a rupicolous species in the wild environment of no epidemiological importance. In order to test the assumption that sister species share biological traits, comparative studies of their development cycle and blood ingestion were conducted. METHODS: Eggs laid by five field females of each species were randomly selected. The nymphs were observed daily and fed on mice weekly. The time required to pass through the different stages to adulthood was recorded in days. The triatomines were weighed individually before and after feeding. The mortality rate according to each nymphal stage was calculated. RESULTS AND CONCLUSIONS: Analysis of the results shows that they display only minor biological differences even though they exhibit a distinct ecology. This suggests that the biological traits are important criteria to determine the relationship between species.

Transport of Pirarucu Arapaima gigas juveniles in plastic bag

This study examined the stress response of pirarucu juveniles in a closed system transport. Pirarucu (Arapaima gigas) is a native Amazonian fish species from the Osteoglossidae family and an obligated air breather. A short duration transport trial (6h) was undertaken comparing closed polyethylene bags filled with atmospheric air (Air group) and bags filled with pure oxygen (Oxi group). Dissolved oxygen was the only water parameter that presented a difference between fish groups, and was saturated in the oxi group as expected. There was no mortality in either group after transport. Fish feeding was observed 36 h after transport for all fish, and normal feeding consumption was observed at 72 h. In both groups physiological responses were similar. Cortisol did not show any significant alteration during the sampled period. Unlike most fish species, cortisol values were unaltered in both groups during sampling, while glucose presented a significant change up to 12 h after transport. The results showed that pirarucu transport in plastic bags could be made with either atmospheric air or pure oxygen, since physiological response to stress, water quality and feeding behavior after 36 h were similar in both groups.

Cooking process evaluation on mercury content in fish

This study evaluated different cooking processes (roasted, cooked and fried) on total mercury (Hg) content in fish species most consumed by Manaus residents and surrounding communities, Amazon region. The results obtained for total Hg in natura and after the three types of preparation (roasted, cooked and fried) for 12 fish species showed a significant Hg concentration variation. In the present study the cooked and frying processes resulted in higher Hg losses for Pacu, Pescada, Jaraqui, Curimatã, Surubin and Aruanã fish species, most of them presenting detritivorous and carnivorous feeding habits. The higher Hg losses in the roasting process occurred for Sardinha, Aracu, Tucunaré, Pirapitinga, Branquinha and Tambaqui fish species, most of them being omnivorous and herbivorous fish species. Some micronutrients (Ca, Fe, K, Na, Se and Zn) in fish species in natura were also determined in order to perform a nutritional evaluation regarding these micronutrients.

Logificação da Psicologia o itinerário intelectual de Edmundo Curvelo sobre a Mente, a Lógica e a Filosofia

Tese de Doutoramento em Filosofia - Especialidade de Filosofia da Mente

The Brugada syndrome. Outcome of one case

The Brugada syndrome is a rare condition, and due to its mutating manner of presentation it may be difficult to diagnose. We report one case and discuss the diagnostic aspects and the clinical outcome of one patient with characteristic findings of this syndrome. These findings are especially defined by J-ST elevation in the right leads of serial electrocardiographic records, wide oscillations of J points and ST segments during 24-hour Holter monitoring, and nocturnal sudden death. We stress the importance of the Holter monitor findings for diagnostic complementation. Through this method it is possible to establish a correlation between vigil activities and sleep and the variability of the degree of impairment in ventricular repolarization.

Вариации повторяемости среднечасовых концентраций приземного озона (КПО) в Тбилиси

განხილულია ქ. თბილისში 1980-2003, 1980-1991 და 1992-2003 წლებში მოკ-ის საშუალოსაათობრივი მნიშვნელობების განმეორადობის ცვალებადობის საკითხი წელიწადისთვის, ცივ და თბილ ნახევარწლისთვის. განხილულია აგრეთვე ადამიანის ჯანმრთელობაზე და აგრეთვე მცენარეებზე ნეგატიურად მოქმედ მოკ-ის განმეორადობის დინამიკა მოკ-ის ისეთ მნიშვნელობებისთვის, რომელიც მოქმედ ზღვრულ დასაშვებზე მაღალია.

Изменчивость среднедневных и часовых значений концентрации приземного озона в Тбилиси в 1980-2003 гг.

მოყვანილია 1980-1991 და 1992-2003 წლებში ქ. თბილისში მიწისპირა ოზონის კონცენტრაციის საშუალო დღიური და საათობრივი მნიშვნელობების სტატისტიკური მახასიათებლები და კვლევის შედეგები დღის 11-დან 19 საათამდე გაზომილი წლის და წელიწადის თბილი და ცივი პერიოდების მონაცემების მიხედვით

Laboratory indicators for monitoring HIV disease

Immunological monitoring of disease progression following HIV infection and seroconversion illness, latency and AIDS, not only helps in the basic investigation of the natural history of the viral infection in man, but also can assist in prognosis and treatment of AIDS-defining illnesses. However, outside clinical trials, these tests should be selected and used in clinical practice only if they are validated as relevant and effective. The absolute CD4+ T-helper lymphocyte count, measured by flow cytometry, has emerged as the best available investigation, but needs care in sampling due to diurnal and circadian rhythms, effects of age, pregnancy, therapy, intercurrent infections and technique. Sampling should provide a baseline and trends - monthly intervals initially, then quarterly in uncomplicated cases. Thresholds may be given for counts (e.g. 200/µl) below which prophylaxis against pneumocystis pneumonia should be administered, and repeating persistently low counts (e.g. below 50/µl) is seldom helpful in practice. Serum levels of beta-2 microglobulin, neopterin and immunoglobulins rarely add information. Physicians and laboratories should have testing guidelines based on clinical audit of best practice, based in turn on scientific understanding of the immunological processes involved.

European Society of Hypertension practice guidelines for ambulatory blood pressure monitoring.

Given the increasing use of ambulatory blood pressure monitoring (ABPM) in both clinical practice and hypertension research, a group of scientists, participating in the European Society of Hypertension Working Group on blood pressure monitoring and cardiovascular variability, in year 2013 published a comprehensive position paper dealing with all aspects of the technique, based on the available scientific evidence for ABPM. The present work represents an updated schematic summary of the most important aspects related to the use of ABPM in daily practice, and is aimed at providing recommendations for proper use of this technique in a clinical setting by both specialists and practicing physicians. The present article details the requirements and the methodological issues to be addressed for using ABPM in clinical practice, The clinical indications for ABPM suggested by the available studies, among which white-coat phenomena, masked hypertension, and nocturnal hypertension, are outlined in detail, and the place of home measurement of blood pressure in relation to ABPM is discussed. The role of ABPM in pharmacological, epidemiological, and clinical research is also briefly mentioned. Finally, the implementation of ABPM in practice is considered in relation to the situation of different countries with regard to the reimbursement and the availability of ABPM in primary care practices, hospital clinics, and pharmacies.

Getting a good start: healthy eating from one to five

This booklet outlines advice on many key nutritional issues for children aged one to five. It includes information on how to provide a healthy, balanced diet for this age group, guidance on suitable snacks and drinks, feeding a vegetarian child, vitamin supplements and iron, making the most of mealtimes and how to deal with fussy eaters.

Tetania secundaria a raquitismo carencial.

Hypocalcemia is an uncommon illness in children. In developed countries the incidence of rickets has decreased significantly, although last years this pathology is increasing at the expense of immigration. Its etiology is due to different factors such as low sun exposure, inadequate clothing and bad feeding and excessive contributions in phytates, exclusive breastfeeding and genetic factors. We report a case of a teenager 13 year old from Pakistan, who consulted for myoclonus, paresthesias, hand midwife and asymmetry walking. The laboratory emphasizes hypocalcemia deficit of 25 (OH) D and increased parathyroid hormone. Administration of calcium and vitamin D along with changes in his diet normalized clinical and laboratory parameters. Due to increased migration, the lack of sun exposure and inadequate supply this disease which was almost forgotten will appear another time.

The behaviour of mosquitoes in relation to humans under holed bednets: the evidence from experimental huts

The physical integrity of bednets is a concern of national malaria control programs, as it is a key factor in determining the rate of replacement of bednets. It is largely assumed that increased numbers of holes will result in a loss of protection of sleepers from potentially infective bites. Experimental hut studies are valuable in understanding mosquito behaviour indoors, particularly as it relates to blood feeding and mortality. This review summarises findings from experimental hut studies, focusing on two issues: (i) the effect of different numbers or sizes of holes in bednets and (ii) feeding behaviour and mortality with holed nets as compared with unholed nets. As might be expected, increasing numbers and area of holes resulted in increased blood feeding by mosquitoes on sleepers. However, the presence of holes did not generally have a large effect on the mortality of mosquitoes. Successfully entering a holed mosquito net does not necessarily mean that mosquitoes spend less time in contact with the net, which could explain the lack in differences in mortality. Further behavioural studies are necessary to understand mosquito behaviour around nets and the importance of holed nets on malaria transmission.