23 resultados para Fiber consumption
Resumo:
Beaver only had been found in Portugal in a Chalcolithic locality, the Vila Nova de S. Pedro castrum. It has now been identified in the Upper Paleolithic (Solutrean) from Gruta do Caldeirão, near Tomar. The species has been found recently at «Gruta do Almonda»; 4 teeth were collected in bed C, older than a Solutrean sequence (see Anexo for details). The species seems to have been rare, as it was also the case with portuguese Miocene Castoridae Enroxenomys minutus and Chalicomys jaegeri. If account is taken of the presence in the Middle Ages until Castille of words meaning beaver (relared to the popular latin Fiber/Biber), it is obvious that these animais still existed then. Such nouns were largely predominant over rhe rather erudite latin (greek deríved) words as Castor,-óris and derived ones, as it could be expected. This allowed us to recognize that veiro should be the corresponding word with Fiber affinities in archaic portuguese. It was previously supposed to mean only expensive furs then imported into Portugal. Indeed it was also a zoonym. Anywày, beaver should be scarce by XIIIth century since it is not included in the quite detailed price list imposed by the «Lei da Almotaçaria» from December 26, 1253 (see Quadro II). Toponyms in veiro and derived words (fig. 2; Quadro III) (plural, feminines, diminutives, inhabited places) give a resrrictive view of rhe Middle Age distribution. Some of them are certainly older than Portugal itself (firsr half of XIlth cenrury); others existed by the XIVth century bur were probably older. Some rare toponyms seem to be derived from the erudite latin Castor,-óris. Nothing suggests that these words were still in use as zoonyms during the Middle Ages. All toponyms are located in regions near rivers and other freshwaters ecologically suitable for beavers, so we can approximately retrace its former, Middle Age disrribution in Portugal (fig. 2; Quadro III). Most of them are locared in the Center-West and Northwest of Portugal, with a suitable c1imate (rainfall in general over 800 mílimerers per year); the only sure geographical exception is Veiros, in Alto Alentejo province, in a region with comparable precipitations and less dry climate conditions than mosr of the territories South of rhe Tagus. There are less and less of these toponyms towards rhe South and the inner part of the country, and they are enrirely lacking in all drier regions from Trás-os-Montes, Beira, Alentejo beyond Tagus' basin, and in Algarve. Nothing suggests beavers lived there, No post-medieval toponym is known, nor any reference after middle XVth century. No such locality was at, or close by to, any frontier. Hence the hypothesis of veiro (et al.} as meaning but points where expensive furs (supposedly known as veiros in general but without c1early saying from what animal they were obrained from) is to be discarded. During the Middle Ages, beaver discriburion concerned all the main river basins from Minho to Tagus ones. Quite rarefied in rhe XIIIth, the beavers may have disappeared from Portugal during the XVth century. Ecological requiremenrs restricted their former distriburion. Vulnerability to natural causes (i.e., severe drought) and to human pressure may have accounted heavily for this species' extinction. Last (1446) reference for Portugal known to us suggests the species was by then almost extinct.
Resumo:
The enzyme hydrogenase isolated from the sulphate reducing anaerobic bacterium Desulfovibrio gigas was encapsulated in reverse micelles of AOT–water–isooctane. The enzyme ability to consume molecular hydrogen was studied as a function of the micelle size (given by Wo = [H2O]/[organic solvent]). A peak of catalytic activity was obtained for Wo = 18, a micelle size theoretically fitting the heterodimeric hydrogenase molecule. At this Wo value, the recorded catalytic activity was slightly higher than in a buffer system(Kcat = 169.43 s−1 against the buffer value of 151 s−1). The optimal buffer used to encapsulate the enzyme was found to be imidazole 50 mM, pH 9.0. The molecular hydrogen production activity was also tested in this reverse micelle medium.
Resumo:
IEEE Electron Device Letters, VOL. 29, NO. 9,
Resumo:
Beaver only had been found in Portugal in a Chalcolithic locality, the Vila Nova de S. Pedro castrum. It has now been idenrified in the Upper Paleolithic (Solurrean) from Gruta do Caldeirão, near Tomar. The species has been found recently at «Gruta do Almonda»; 4 teeth were collected in bed C, older than a Solutrean sequence (see Anexo for details). The species seems to have been rare, as it was also the case with portuguese miocene Castoridae Enroxenomys minutus and Chalicomys jaegeri. If account is taken of the presence in the Middle Ages until Castille of words meaning beaver (related to the popular latin Fiber/Biber), it is obvious that these animals still existed then. Such nouns were largely predominant over the rather erudite larin (greek derived) words as Castor, -óris and derived ones, as it could be expected. This allowed us to recognize that veiro should be the corresponding word with Fiber affinities in archaic portuguese. It was previously supposed to mean only expensive furs then imported into Portugal. Indeed it was also a zoonym. Anyway, beaver should be scarce by XIIIth century since it is not included in the quite detailed price list imposed by the «Lei da Almotaçaria» from December 26, 1253 (see Quadro II). Toponyms in veiro and derived words (fig. 2; Quadro III) (plural, feminines, diminutives, inhabited places) give a restrictive view of the Middle Age distribution. Some of them are certainly older than Portugal itself (first half of XIIth century); others existed by the XIVth century but were probably older. Some rare toponyms seem to be derived from rhe erudite latin Castor, -óris. Nothing suggests that these words were still in use as zoonyms during the Middle Ages. All toponyms are located in regions near rivers and other freshwaters ecologically suitable for beavers, so wecan approximately retrace irs former, Middle Age distribution in Portugal (fig. 2; Quadro III). Most of them are located in the Center-West and Northwest of Portugal, with a suitable c1imate (rainfall in general over 800 milimeters per year); the only sure geographical exception is Veiros, in Alto Alentejo province, in a region with comparable precipitations and less dry climare conditions than most of the territories South of the Tagus. There are less and less of these toponyms towards the South and the inner part of the country, and they are enrirely lacking in ali drier regions from Trás-os-Montes, Beira, Alentejo beyond Tagus' basin, and in Algarve. Nothing suggests beavers lived there, No pose-medieval toponym is known, nor any reference after middle XVth century. No such locality was at, or close by to, any frontier. Hence the hypothesis of veiro (e: al.) as meaning but points where expensive furs(supposedly known as veiros in general but without clearly saying from what animal they were obtained from) is to be discarded. During the Middle Ages, beaver distribution concerned all the main river basins from Minho to Tagus ones. Quice racefied in the XIIIth, the beavers may have disappeared from Portugal during the XVth century. Ecological requirements restricted their former distribution. Vulnerability to natural causes (i.e., severe drought) and to human pressure may have accounted heavily for this species extinction. Last (1446) reference for Portugal known to us suggests the species was by then almost extinct.
Resumo:
Background: Little is known about the risk of progression to hazardous alcohol use in people currently drinking at safe limits. We aimed to develop a prediction model (predictAL) for the development of hazardous drinking in safe drinkers. Methods: A prospective cohort study of adult general practice attendees in six European countries and Chile followed up over 6 months. We recruited 10,045 attendees between April 2003 to February 2005. 6193 European and 2462 Chilean attendees recorded AUDIT scores below 8 in men and 5 in women at recruitment and were used in modelling risk. 38 risk factors were measured to construct a risk model for the development of hazardous drinking using stepwise logistic regression. The model was corrected for over fitting and tested in an external population. The main outcome was hazardous drinking defined by an AUDIT score >= 8 in men and >= 5 in women. Results: 69.0% of attendees were recruited, of whom 89.5% participated again after six months. The risk factors in the final predictAL model were sex, age, country, baseline AUDIT score, panic syndrome and lifetime alcohol problem. The predictAL model's average c-index across all six European countries was 0.839 (95% CI 0.805, 0.873). The Hedge's g effect size for the difference in log odds of predicted probability between safe drinkers in Europe who subsequently developed hazardous alcohol use and those who did not was 1.38 (95% CI 1.25, 1.51). External validation of the algorithm in Chilean safe drinkers resulted in a c-index of 0.781 (95% CI 0.717, 0.846) and Hedge's g of 0.68 (95% CI 0.57, 0.78). Conclusions: The predictAL risk model for development of hazardous consumption in safe drinkers compares favourably with risk algorithms for disorders in other medical settings and can be a useful first step in prevention of alcohol misuse.
Resumo:
A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics
Resumo:
A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
Resumo:
A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
Resumo:
A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
Resumo:
A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
Resumo:
A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
Resumo:
Dissertation for obtaining the Master degree in Membrane Engineering
Resumo:
Deep-eutectic solvents (DES) are considered novel renewable and biodegradable solvents, with a cheap and easy synthesis, without waste production. Later it was discovered a new subclass of DES that even can be biocompatible, since their synthesis uses primary metabolites such as amino acids, organic acids and sugars, from organisms. This subclass was named natural deep-eutectic solvents (NADES). Due to their properties it was tried to study the interaction between these solvents and biopolymers, in order to produce functionalized fibers for biomedical applications. In this way, fibers were produced by using the electrospinning technique. However, it was first necessary to study some physical properties of NADES, as well as the influence of water in their properties. It has been concluded that the water has a high influence on NADES properties, which can be seen on the results obtained from the rheology and viscosity studies. The fluid dynamics had changed, as well as the viscosity. Afterwards, it was tested the viability of using a starch blend. First it was tested the dissolution of these biopolymers into NADES, in order to study the viability of their application in electrospinning. However the results obtained were not satisfactory, since the starch polymers studied did not presented any dissolution in any NADES, or even in organic solvents. In this way it was changed the approach, and it was used other biocompatible polymers. Poly(ethylene oxide), poly(vinyl alcohol) and gelatin were the others biopolymers tested for the electrospinning, with NADES. All polymers show good results, since it was possible to obtain fibers. However for gelatin it was used only eutectic mixtures, containing active pharmaceutical ingredients (API’s), instead of NADES. For this case it was used mandelic acid (antimicrobial properties), choline chloride, ibuprofen (anti-inflammatory properties) and menthol (analgesic properties). The polymers and the produced fibers were characterized by scanning electron microscope (SEM), Transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR). With the help of these techniques it was possible to conclude that it was possible to encapsulate NADES within the fibers. Rheology it was also study for poly(ethylene oxide) and poly(vinyl alcohol), in a way to understand the influence of polymer concentration, on the electrospinning technique. For the gelatin, among the characterization techniques, it was also performed cytotoxicity and drug release studies. The gelatin membranes did not show any toxicity for the cells, since their viability was maintained. Regarding the controlled release profile experiment no conclusion could be drawn from the experiments, due to the rapid and complete dissolution of the gelatin in the buffer solution. However it was possible to quantify the mixture of choline chloride with mandelic acid, allowing thus to complete, and confirm, the information already obtained for the others characterization technique.
Resumo:
Nowadays, reducing energy consumption is one of the highest priorities and biggest challenges faced worldwide and in particular in the industrial sector. Given the increasing trend of consumption and the current economical crisis, identifying cost reductions on the most energy-intensive sectors has become one of the main concerns among companies and researchers. Particularly in industrial environments, energy consumption is affected by several factors, namely production factors(e.g. equipments), human (e.g. operators experience), environmental (e.g. temperature), among others, which influence the way of how energy is used across the plant. Therefore, several approaches for identifying consumption causes have been suggested and discussed. However, the existing methods only provide guidelines for energy consumption and have shown difficulties in explaining certain energy consumption patterns due to the lack of structure to incorporate context influence, hence are not able to track down the causes of consumption to a process level, where optimization measures can actually take place. This dissertation proposes a new approach to tackle this issue, by on-line estimation of context-based energy consumption models, which are able to map operating context to consumption patterns. Context identification is performed by regression tree algorithms. Energy consumption estimation is achieved by means of a multi-model architecture using multiple RLS algorithms, locally estimated for each operating context. Lastly, the proposed approach is applied to a real cement plant grinding circuit. Experimental results prove the viability of the overall system, regarding both automatic context identification and energy consumption estimation.