Energy cost of activity assessed by indirect calorimetry and a (CO2)-C-13 breath test

Purpose: The aim of this study was to assess the accuracy of a (CO2)-C-13 breath test for the prediction of short-duration energy expenditure. Methods: Eight healthy volunteers walked at 1.5 km.h(-1) for 60 min followed by 60-min recovery. During this time, the energy cost of physical activity was measured via respiratory calorimetry and a C-13 bicarbonate breath test. A further eight subjects were tested using the same two methods during a 60-min cycle at 0.5 kp. 30 ipm followed by a 60-min recovery. The rate of appearance of (CO2)-C-13, (RaCO2) was measured and the mean ratio, (V) over dot CO2/RaCO2 was used to calculate energy expenditure using the isotopic approach. Results: As would be expected, there was a significant difference in the energy cost of walking and cycling using both methods (P < 0.05). However. no significant differences were observed between respiratory calorimetry and the isotope method for measurement of energy expenditure while walking or cycling. Conclusions: These data suggest that the C-13 breath test is a valid method that can be used to measure the energy cost of short duration physical activity in a field setting.

A new technique for the quantification of peripheral edema with application in both unilateral and bilateral cases

Current noninvasive techniques for the routine and frequent quantification of peripheral lymphedema in patients are total limb volume measurement (by water immersion or by circumferential measurements) and bioelectrical impedance analysis (BIA). However both of these techniques require standardizing the measurement using a contralateral measurement from the unaffected limb, Hence these techniques are essentially restricted to unilateral lymphedema. This paper describes the results from a preliminary study to investigate an alternative approach to the analysis of the data from multiple frequency BIA to produce an index of lymphedema without the need for normalization to another body segment. Twenty patients receiving surgical treatment for breast cancer were monitored prior to surgery and again after diagnosis with unilateral lymphedema. The data recorded were total limb volume, by circumferential measurements; and BIA measurements of both limbs. From these measurements total limb volumes and extracellular fluid volumes were calculated and expressed as ratios of the affected limb to that of the unaffected limb. An index of the ratio of the extracellular fluid volume to the intracellular fluid volume was determined. This ECW/ICW index was calculated for both the affected and unaffected limbs at both measurement times. Results confirmed that the established techniques of total limb volume and extracellular fluid volume normalized to the unaffected contralateral limb were accurate in the detection of lymphedema (p < 10(-6)). Comparison of the ECW/ICW index from the affected limb after diagnosis with that from the pre-surgery measurement revealed a significant (p< 10(-6)) and considerable (75%) increase. The results of this pilot study suggest that by using multiple frequency bioelectrical impedance analysis, an index of the ECW/ICW ratio can be obtained and this index appears to have an equal, or better, sensitivity, than the other techniques in detecting lymphedema. More importantly, this index does not require normalization to another body segment and can be used to detect all types of peripheral edema including both unilateral and bilateral lymphedema.

Chemical, morphological, rheological and thermal properties of Solanum lycocarpum phosphorylated starches

The increasing need for starches with specific characteristics makes it important to study unconventional starches and their modifications in order to meet consumer demands. The aim of this work was to study physicochemical characteristics of native starch and phosphate starch of S. lycocarpum. Native starch was phosphated with sodium tripolyphosphate (5-11%) added with stirring. Chemical composition, morphology, density, binding ability to cold water, swelling power and solubility index, turbidity and syneresis, rheological and calorimetric properties were determined. Phosphorus was not detected in the native sample, but the phosphating process produced modified starches with phosphorus contents of 0.015, 0.092 and 0.397%, with the capacity of absorbing more water, either cold or hot. Rheological data showed the strong influence of phosphorus content on viscosity of phosphate starch, with lower pasting temperature and peak viscosity higher than those of native starch. Enthalpy was negatively correlated with the phosphorus content, requiring 9.7; 8.5; 8.1 and 6.4 kJ g-1 of energy for the transition from the amorphous to the crystalline state for the starch granules with phosphorus contents of 0; 0.015; 0.092 and 0.397%, respectively. Cluster analysis and principal component analysis showed that starches with 0.015 and 0.092% phosphorus have similar characteristics and are different from the others. Our results show that the characteristics of phosphate modified S. lycocarpum starch have optimal conditions to meet the demands of raw materials, which require greater consistency in stickiness, combined with low rates of retrogradation and syneresis.

Caracteriza����o de ��guas do processo e optimiza����o dos consumos de ��gua nos v��rios circuitos da Petibol, S.A. ��� Embalagens de Pl��stico

A empresa Petibol, S.A. ��� Embalagens de pl��stico centra-se na produ����o de embalagens de pl��stico a partir da mat��ria-prima Poliestireno Expandido (EPS) e Polipropileno Expandido (EPP). A empresa possui uma preocupa����o ao n��vel da qualidade da ��gua e do aproveitamento energ��tico, tendo desta forma surgido a realiza����o do estudo na unidade industrial, com o objectivo de anular e/ou diminuir as poss��veis lacunas existentes na unidade industrial. Numa primeira etapa foi realizada uma caracteriza����o global �� qualidade da ��gua e �� empresa, actualizando-se os esquemas j�� existentes, contabilizando-se os custos actuais relativamente aos processos no circuito da ��gua (arrefecimento, aquecimento e pressuriza����o), e por fim, efectuou-se um levantamento in loco do circuito de ��gua, relativamente �� press��o, temperatura e caudal. Numa fase posterior, foram propostos equipamentos e processos, tendo em vista a colmata����o dos problemas identificados, realizando-se um subsequente estudo relativamente aos custos inerentes a esses novos processos. A caracteriza����o �� ��gua foi avaliada em diferentes pontos do circuito industrial, tendo-se determinado na Sala de Bombagem que o filtro de areia n��o possu��a as dimens��es mais apropriadas, existindo tamb��m um problema a n��vel mec��nico associado ao processo de contra-lavagem. Tais factos podem ser a causa da ocorr��ncia de um aumento do teor de s��lidos ap��s a passagem na camada filtrante. Relativamente ao amaciador, este deveria amaciar de forma completa a ��gua para alimenta����o �� caldeira, embora se tenha registado �� sa��da do amaciador uma dureza de 21,3 mg/L, denunciando problemas na troca i��nica. No que toca �� ��gua de alimenta����o �� caldeira, verifica-se a exist��ncia de par��metros que n��o se encontram de acordo com os crit��rios enunciados para uma ��ptima qualidade, sendo eles o pH (10,14), condutividade (363 ��S/cm), teor de ferro (1,21 mg/L) e a dureza (16 mg/L). De salientar que somente o teor de cobre, que se encontra em quantidades vestigiais, apresenta-se de acordo com os valores impostos. No que respeita �� ��gua da caldeira, esta apresenta par��metros incompat��veis com os recomendados, sendo eles a condutividade (7350 ��S/cm), teor de s��lidos dissolvidos (5248 mg/L) e alcalinidade total (780 mg/L). De referir que o valor de pH (11,8) n��o se encontra de acordo com a aplica����o do tratamento ���fosfato-pH coordenado���. Em rela����o aos par��metros com valores que se encontram dentro dos limites, estes correspondem �� dureza (0 mg/L), ao teor de fosfatos (45 mg/L) e teor de s��lica (0 mg/L). A ��gua do circuito de arrefecimento foi sujeita a uma an��lise microbiol��gica, que corroborou a presen��a de um biofilme. Um dos problemas enunciados pela empresa, prendia-se com a impossibilidade de descarga, no colector municipal, dos condensados dos compressores, visto apresentarem uma quantidade de ��leo de cerca de 43,3 mg/L, equivalente a quatro vezes o valor limite de emiss��o, de acordo com a legisla����o municipal. Por fim, o efluente de descarga industrial apresenta um valor de pH (10,3) acima do intervalo permitido por lei (6,0 ��� 9,0), sendo que a corrente que mais contribui para este acr��scimo de pH corresponde �� corrente proveniente da ��gua de purga, visto esta apresentar um valor de pH de 12,22. De maneira a contornar os par��metros enunciados, �� proposto a substitui����o do filtro de areia da Sala de Bombagem, assim como a inser����o de um conjunto de medidas de remo����o de ferro e desinfec����o, sendo a conjuga����o de arejamento, coagula����o, filtra����o e desinfec����o, por parte do hipoclorito, a proposta apresentada. Aos condensados dos compressores �� apresentado um sistema de separa����o, que possibilita a remo����o do ��leo da ��gua, e uma consequente descarga da mesma. Actualmente, n��o existe qualquer filtro de areia no circuito de arrefecimento da ��gua, sendo proposto assim esse equipamento, de forma a minorar o desenvolvimento da popula����o microbiana, bem como a permitir uma maior efici��ncia na transfer��ncia de calor na torre de arrefecimento. Relativamente �� descarga industrial, �� recomend��vel a coloca����o de um sistema de regulariza����o autom��tica de pH. A inser����o de uma v��lvula de tr��s vias permite um aproveitamento energ��tico e de ��gua, a partir da conflu��ncia da ��gua oriunda dos furos com a ��gua do tanque de ��gua fria, sendo posteriormente alimentada �� central de v��cuo. No estudo da recupera����o energ��tica, um outro equipamento avaliado correspondeu �� serpentina, no entanto, verificou-se que a poupan��a no consumo de g��s natural era de apenas 0,005%, o que n��o se mostrou uma proposta vi��vel. O or��amento de todos os equipamentos �� de 11.720,76 ���, possibilitando n��o s�� um melhor funcionamento industrial, como um menor impacto a n��vel ambiental. Os custos futuros de funcionamento aumentam em 3,36%, tendo a pressuriza����o um aumento do seu custo em 3,4% em rela����o ao custo actual, verificando-se um custo anual de 10.781,21���, em rela����o aos processos de arejamento, coagula����o e desinfec����o.

Novos artigos e sistemas no processamento do couro

A necessidade de diminuir os consumos de energia, n��o s�� por quest��es financeiras mas tamb��m por quest��es ambientais, faz com que sejam feitos esfor��os no sentido da implementa����o de energias renov��veis bem como da melhoria e expans��o das solu����es t��cnicas j�� conhecidas. Uma das maiores fontes de energia renov��vel, sen��o mesmo a maior, �� a energia solar que, no futuro, ter�� uma contribui����o muito significativa, quer na satisfa����o dos consumos energ��ticos, quer na racionaliza����o da sua utiliza����o, isto ��, na melhoria da efici��ncia do consumo. O presente trabalho focou-se na procura de um sistema solar t��rmico para o pr��-aquecimento da ��gua quente a ser utilizada numa f��brica de curtumes, a empresa Curtumes Aveneda, Lda. Em simult��neo, desenvolveram-se e optimizaram-se processos de produtos espec��ficos que o mercado exige actualmente, visando uma economia de recursos (mat��rias-primas, ��gua e energia), objectivando sempre a sua viabilidade econ��mica. No que respeita �� procura do sistema solar t��rmico, inicialmente foram realizados levantamentos relativos ao consumo de ��gua, quente e fria, na respectiva empresa. Esta avalia����o focou-se em todos os sectores consumidores intensivos de ��gua, tais como a ribeira, curtume e a tinturaria, excluindo o sector de acabamento uma vez que o consumo aqui �� insignificante relativamente aos sectores citados anteriormente. Com base no levantamento efectuado foi dimensionado um sistema solar t��rmico para o pr�� aquecimento da ��gua quente que conduz a uma economia anual de 107.808,3 kWh de energia t��rmica, representativa de 29% do consumo anual de energia t��rmica de aquecimento de ��gua. Foi efectuada an��lise econ��mica deste investimento que mostrou um ��ndice de rentabilidade superior �� unidade e um tempo de retorno do investimento de 9 anos. Desenvolveu-se com sucesso um produto de couro a partir de wet-blue, designado por crispado, produto normalmente produzido a partir da pele em tripa e muito dif��cil de obter a partir de wet-blue. Este produto caracteriza-se pela sua forma granular irregular e firme da pele. O processo desenvolvido foi ainda optimizado no sentido da redu����o do consumo de ��gua e de energia. Tendo em conta a necessidade da empresa tamb��m se tentou melhorar as caracter��sticas do couro wet-white, muito solicitado actualmente, com resultados positivos no que respeita �� temperatura de contrac����o do couro e ��s propriedades f��sico-mec��nicas mas sem se atingir o principal objectivo que seria tornar a cor mais clara e mais pura. Foram desta forma dados contributos importantes para a empresa que, assim, dimensionou um sistema mais econ��mico para o aquecimento de ��gua que vai adoptar e ficou com um processo dispon��vel para produzir um produto at�� ent��o n��o conseguido.

Controladores lingu��sticos Fuzzy

Trabalho Final de Mestrado para obten����o do grau de Mestre em Engenharia Mec��nica

Sistema de Torre de Refrigera����o

Mestrado em Engenharia Qu��mica - Ramo Optimiza����o Energ��tica na Ind��stria Qu��mica

The Farol Deposit (Dep��sito do Farol) ��� a Pleistocene beach deposit from Cape Mondego (Figueira da Foz, West Central Portugal)*

Among the Pleistocene and Holocene units recorded near the marine cliffs of Cape Mondego (Figueira da Foz, West Central Portugal) stands out the Farol Deposit (Dep��sito do Farol), at an altitude of ��95 m above present sea level. It is a marine terrace with three exposures of interstratified conglomerates and sands, overlapped by calclititic-fanglomerates. This sedimentary setting indicates that deposition took place in a seashore environment influenced by the proximity of a marine palaeocliff. The deposit has an interesting subfossil fauna with abraded and fragmented shells of Nucella lapillus (LINN��, 1758), Patella vulgata (LINN��, 1758) and Littorina littorea (LINN��, 1758), suggesting the existence of an environment with colder surface seawater, when compared with the present day Portuguese seashore. These specimens belonged to marine communities adapted to live in intertidal rocky platforms, which have been exposed to the cyclic action of waves and tidal flows, on the swash and surf zones. The Farol Deposit can be related to an Early/Middle Pleistocene ���cold-water��� episode, earlier to the Isotopic Stages 7 and 11. This episode occurred before the deposition of the units Quiaios Sands (Areias de Quiaios) and Cantanhede Sands (Areias de Cantanhede) (Sicilian?), but later than the Arazede Sands (Areias de Arazede) and Marinha das Ondas Sands (Areias de Marinha das Ondas) (Early Pleistocene).

Origem An��mala da Art��ria Coron��ria Esquerda a Partir da Art��ria Pulmonar

OBJECTIVE: To assess the frequency and severity of the anomalous origin of the left coronary artery (ALCA) from the pulmonary artery (PA). DESIGN OF THE STUDY: Prospective study of case series between March 1991 and December 1994. SETTING: Referral-based Paediatric Cardiology Department of a Tertiary Care Center. PATIENTS AND METHODS: Five consecutive patients (pts) with anomalous origin of the LCA from the PA; there were three infants aged 4 months and two children one 8 year and one 9 year old. There were three girls and two boys. All pts had clinical and 2D-echo and Doppler investigation prior to cardiac catheterization (CC). Indication for CC was based in the association of symptoms and signs of myocarditis or dilated cardiomyopathy of acute or subacute onset and electrocardiographic (ECG) signs of ischemia in infants. In older patients (pts) diagnosis was suspected mainly from ECG. During CC in all pts, aortograms and when necessary selective coronary angiograms were performed. Surgical correction was performed in all children. In two pts stress exercise ECG and stress Thallium studies before and after surgery were performed. RESULTS: two pts had "adult" an three had "infantile" type of ALCA from the PA. CC was performed and diagnosis was confirmed at surgery in all cases. In one child, correct diagnosis was made by ECO prior to CC and in one case LCA to PA fistula was suspected on Colour-Doppler study. No complications were attributed to CC. Several types of surgery were performed: reimplantation of the ALCA from the PA to the aorta (three pts); tunnel connection of the aorta to the ALCA via the PA (one pt) and left internal mammary to LCA anastomosis (one pt). Two infants died intraoperatively due to extensive myocardial infarction and poor left ventricular function. All the three survivors are asymptomatic after a mean follow up of 34 months. Two oldest pts are currently in New York Heart Association functional class I with normal ECG and improved myocardial perfusion on Thallium scan despite almost total occlusion of LCA at the site of implantation in the aorta as diagnosed on coronary angiogram. CONCLUSIONS: ALCA from PA is associated with major morbidity and mortality. Diagnosis should be suspected in pts with unexplained myocardial ischemia on ECG and even more if it is associated to clinical signs of dilated cardiomyopathy or myocarditis. Careful assessment on ECO and pulsed Doppler and colour flow mapping should make the diagnosis in most cases. Although surgery can be performed based only on ECO diagnosis, we strongly advise for angiography in all cases as in our experience there are false negative diagnosis by ECO. Preoperative Thallium studies can be useful for the selection of the type of surgery as pts with very little viable myocardium will not survive the establishment of a direct systemic to coronary blood flow and may be candidates for heart transplantation.

Novel transcription factors regulating the expression of the rice gene OsDREB1B

Dissertation presented to obtain the Ph.D degree in Biology

Human ceruloplasmin and neurotransmitters: complex stabilization and crystallization

Dissertation to obtain a Master Degree in Molecular Genetics and Biomedicine at Faculty of Sciences and Technology,Universidade Nova de Lisboa

Moisture-induced degradation of interfacial bond in FRP-strengthened masonry

Externally bonded strengthening of masonry structures using Fiber Reinforced Polymers (FRPs) has been accepted as a promising technique. Although the effectiveness of FRPs in improving the performance of masonry components has been extensively investigated, their long-term performance and durability remain poorly addressed. This paper, tackling one of the aspects related to durability of these systems, presents an experimental investigation on the effect of long-term (one year) water immersion on the performance of GFRP-strengthened bricks. The tests include materials' mechanical tests, as well as pull-off and single-lap shear bond tests, to investigate the changes in material properties and bond behavior with immersion time, respectively. The effect of mechanical surface treatment on the durability of the strengthened system as well as the reversibility of the degradation upon partial drying are also investigated. The experimental results are presented and critically discussed.

Jute/polypropylene composites: Effect of enzymatic modification on thermo-mechanical and dynamic mechanical properties

In this study, a high-performance composite was prepared from jute fabrics and polypropylene (PP). In order to improve the compatibility of the polar fibers and the non-polar matrix, alkyl gallates with different hydrophobic groups were enzymatically grafted onto jute fabric by laccase to increase the surface hydrophobicity of the fiber. The grafting products were characterized by FTIR. The results of contact angle and wetting time showed that the hydrophobicity of the jute fabrics was improved after the surface modification. The effect of the enzymatic graft modification on the properties of the jute/PP composites was evaluated. Results showed that after the modification, tensile and dynamic mechanical properties of composites improved, and water absorption and thickness swelling clearly decreased. However, tensile properties drastically decreased after a long period of water immersion. The thermal behavior of the composites was evaluated by TGA/DTG. The fiber-matrix morphology in the modified jute/PP composites was confirmed by SEM analysis of the tensile fractured specimens.

Prognostic value of technetium-99m-labeled single-photon emission computerized tomography in the follow-up of patients after their first myocardial revascularization surgery

OBJECTIVE: To assess the prognostic value of Technetium-99m-labeled single-photon emission computerized tomography (SPECT) in the follow-up of patients who had undergone their first myocardial revascularization. METHODS: We carried out a retrospective study of 280 revascularized patients undergoing myocardial scintigraphy under stress (exercise or pharmacological stress with dipyridamole) and at rest according to a 2-day protocol. A set of clinical, stress electrocardiographic and scintigraphic variables was assessed. Cardiac events were classified as "major" (death, infarction, unstable angina) and "any" (major event or coronary angioplasty or new myocardial revascularization surgery). RESULTS: Thirty-six major events occurred as follows: 3 deaths, 11 infarctions, and 22 unstable anginas. In regard to any event, 22 angioplasties and 7 new surgeries occurred in addition to major events, resulting a total of 65 events. The sensitivity of scintigraphy in prognosticating a major event or any event was, respectively, 55% and 58%, showing a negative predictive value of 90% and 83%, respectively. Diabetes mellitus, inconclusive stress electrocardiography, and a scintigraphic visualization of left ventricular enlargement were significant variables for the occurrence of a major event. On multivariate analysis, abnormal myocardial scintigraphy was a predictor of any event. CONCLUSION: Myocardial perfusion tomography with Technetium-99m may be used to identify high-risk patients after their first myocardial revascularization surgery.

Corticosterone shifts reproductive behaviour towards self-maintenance in the barn owl and is linked to melanin-based coloration in females.

Trade-offs between the benefits of current reproduction and the costs to future reproduction and survival are widely recognized. However, such trade-offs might only be detected when resources become limited to the point where investment in one activity jeopardizes investment in others. The resolution of the trade-off between reproduction and self-maintenance is mediated by hormones such as glucocorticoids which direct behaviour and physiology towards self-maintenance under stressful situations. We investigated this trade-off in male and female barn owls in relation to the degree of heritable melanin-based coloration, a trait that reflects the ability to cope with various sources of stress in nestlings. We increased circulating corticosterone in breeding adults by implanting a corticosterone-releasing-pellet, using birds implanted with a placebo-pellet as controls. In males, elevated corticosterone reduced the activity (i.e. reduced home-range size and distance covered within the home-range) independently of coloration, while we could not detect any effect on hunting efficiency. The effect of experimentally elevated corticosterone on female behaviour was correlated with their melanin-based coloration. Corticosterone (cort-) induced an increase in brooding behaviour in small-spotted females, while this hormone had no detectable effect in large-spotted females. Cort-females with small eumelanic spots showed the normal body-mass loss during the early nestling period, while large spotted cort-females did not lose body mass. This indicates that corticosterone induced a shift towards self-maintenance in males independently on their plumage, whereas in females this shift was observed only in large-spotted females.