ESA - Artigos em Revistas Indexados à WoS/Scopus
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- Dynamics of a broadleaved (Castanea sativa) conifer (Pseudotsuga menziesii) mixed stands in Northern PortugalPublication . Luís, Jaime F. Sales; Monteiro, Maria do LoretoIn nature, forest ecosystems are composed by mixtures of species located in the understorey, intermediate and overstorey layers and a potential increase in productivity with mixed stands and plantations, compared to pure stands of the component species is widely accepted, although this has not generally been incorporated into forestry practice. In this experimental planting study, the types of mixtures tested includes three row mixtures with species changing in the planting line, two line mixtures with species changing between the planting line and two monocultures. The species growth pattern was analysed and productivity comparisons between mixed stands and pure stands of the component species were made using the relative yield RY. and relative yield total RYT. concepts. The species shows different top height growth patterns which are not influenced by the mixtures tested. Castanea satiÍa responds well to competitive pressure from Pseudotsuga menziesii which shows a higher productivity. In the row mixtures, the positive effect of interspecific competition yields to RYT values greater than 1.0. Mixture RYT values are steadily increasing with time and C. satiÍa monoculture has been the most attractive economic solution, although its importance compared with the most productive mixtures is diminishing over time. This species mixture represents a flexible silvicultural system, which will be in the future, a very important land use alternative in mountain areas.
- Nest-site selection by roseate terns breeding on aride island, SeychellesPublication . Ramos, JaimeNest-site selection by tropical Roseate Terns (Sterna dougallii) was examined on Aride Island, Seychelles. Continuous variables reflecting concealment of the nest site, shelter, vegetation cover and intraspecific nest density were measured for nest-sites and random points. Seasonal variation in the initiation of nests with overhangs and their influence on hatching success and adult intraspecific aggression towards chicks were also examined. Roseate Terns selected nest-sites closer to taller vertical objects, and with a higher percentage of rocks, logs or branches overhanging the nest than occurred at random points. Nest-sites in small colonies differed more from the available habitat than did those in the main colony. Nesting density was positively correlated with the amount of rock cover. On Aride and other colonies in the tropics Roseate Terns breed at higher densities than their temperate counter-parts and spacing between neighbors may be a main factor in the selection of nest-sites, especially for birds nesting at the peak of the breeding season. Nest-site characteristics, notably overhangs, had no influence on hatching success. However, the proportion of chicks that died from adult pecking was significantly lower in nests with overhangs. Concealment is a main factor of Roseate Tern nest-site selection throughout its breeding range, in both tropical and temperate areas, but the factors selecting for concealment seem to vary amongst colonies. On Aride concealment appeared to be advantageous in defending territories and protecting young chicks from attacks of adults. Artificial overhangs could be provided to enhance chick survival.
- Characteristics of foraging habitats and chick food provisioning by tropical Roseate TernsPublication . Ramos, JaimeI studied tropical Roseate Terns (Sterna dougallii) on Aride Island, Seychelles, between 1997-1999. Productivity in 1998 was 0.58 fledglings/breeding pair, and in 1999 no young fledged. Roseate Terns on Aride concentrated their foraging along the coastline exposed to prevailing winds, with flock size over this area being significantly correlated with amount of food offered to chicks. In 1998, Lesser Noddies (Anous tenuirostris) were present in 91% of the Roseate Tern flocks, but in 1999 occurred in only 32%. During the 1998 successful breeding season, Roseate Terns were associated with dense flocks of Lesser Noddies over predatory fish, whereas during the 1999 failure season most Roseate Tern hocks were either monospecific or mixed with Fairy Terns (Gygis alba), and without predatory fish. The mean flock size of Roseate Terns (82 vs. 6 birds) and the rate of foraging attempts (8.3 vs. 2.8 attempts min(-1)) were significantly greater in association with predatory fish. Mullidae (Parupeneus or Mulloidichthys) were the primary prey taken by Roseate Terns, and alternative sources of food were apparently scarce. The high daily variations in the amount of food brought to chicks, intermediate periods of low food delivery, and an apparent seasonal decline in the amount of food brought to the colony suggest that food is unpredictable on a daily and seasonal basis. Absence of predatory fish may explain complete breeding failures and periods of low food delivery, but the importance of other factors is unknown. Information on the ecology and movement patterns of predatory fish around Aride Island is needed to assist the conservation of the Roseate Terns.
- Seasonal variation in reproductive measures of tropical Roseate Terns Sterna dougallii: previously undescribed breeding patterns in a seabirdPublication . Ramos, JaimeSeasonal variation in egg-laying, egg size, hatching success, hatchling mass, fledging success and chick growth of Roseate Terns Sterna dougallii breeding on Aride Island (Seychelles), Indian Ocean, were studied in 1997 and 1998. I investigated to what extent two patterns, common in a range of species, were followed by tropical Roseate Terns: (a) seasonal decrease in clutch size, egg size and breeding success and (b) an increase in breeding success with increasing egg weight. In 1997 (a poor year), the earliest nesting birds laid significantly smaller eggs, and chicks were lighter at hatching than those of peak nesting birds. The mean clutch size, of 1.04 eggs, showed no seasonal variation and no 'b'-eggs hatched. In 1998 (a good year) the earliest nesting birds laid eggs of similar size and their chicks were of similar weight to those of peak nesting birds. Mean clutch size, of 1.2 5 eggs, increased significantly through the season and about 60% of the 'b'-eggs hatched. In 1997, hatching success was 57% whereas in 1998 it was 80%. In both years, breeding success declined significantly through the season. The fact that the earliest breeding birds laid smaller eggs in a poor year and smaller clutches in a good year is in marked contrast to a range of other species, and to temperate-nesting Roseate Terns. Egg volume explained about half of the variance in hatchling mass in both years, but only 15% of the variation in linear growth rate. Hatching date was the only variable with a significant effect on fledging success. Roseate Terns on Aride seemed to sacrifice egg size and clutch size for earliness of laying. Presumably it is a strategy of older birds to lay as early as possible and may be regarded as a response of tropical Roseate Terns to breeding under relatively poor, and seasonally declining, food conditions.
- An assessment of the nutritional status of a school-aged population from Argelia, ColombiaPublication . Ortega Bonilla, Rubén Andrés; Chito-Trujillo, Diana M.Malnutrition affects most rural areas in Colombian, mainly involving the school-aged population. The aim of this study was to assess the nutritional status of students (n=1,528) attending an Agricultural College in the town of Argelia in south-western Colombia in the Cauca department. Methods The school-aged children’s weight and height were measured and their nutritional status was determined from their body mass index (BMI), according to criteria defined by the World Health Organization (WHO). Anthropometric measurements were analyzed by means of measures of central tendency, stratified by gender and age. The standard error of the difference was estimated to specify the statistical significance of some of the most important differences observed between study indicators; such significance was verified at 0.05 level. Results Prevalence regarding malnutrition and thinness in 5-10 years-old children, a trend towards obesity in adolescents and growth retardation in children and adolescents was established from analysis of the children’s weight (P/E), height for age (H/A) and BMI. Conclusions The results suggested that sports should be encouraged at an early age, as well as training school children and their families regarding healthy eating habits and thus provide scientific support for planning government healthcare agencies’ prevention and control strategies.
- Smart Agents in Industrial Cyber-Physical SystemsPublication . Leitão, Paulo; Karnouskos, Stamatis; Ribeiro, Luis; Lee, Jay; Strasser, Thomas I.; Colombo, Armando W.Future industrial systems can be realized using the cyber-physical systems (CPSs) that advocate the coexistence of cyber and physical counterparts in a network structure to perform the system's functions in a collaborative manner. Multiagent systems share common ground with CPSs and can empower them with a multitude of capabilities in their efforts to achieve complexity management, decentralization, intelligence, modularity, flexibility, robustness, adaptation, and responsiveness. This work surveys and analyzes the current state of the industrial application of agent technology in CPSs, and provides a vision on the way agents can effectively enable emerging CPS challenges.
- Características de la canal de terneros de la Denominación de Origen Protegida MirandesaPublication . Sousa, Fernando Ruivo de; Lorenzo Rodriguez, Jose Manuel; Iglesias, Antonio; Cantalapiedra, Jesús J.; Franco, DanielEl objetivo de este trabajo fue evaluar las características de la canal de la raza Mirandesa. Para llevar a cabo este estudio, un total de 20 animales de la raza Mirandesa fueron sacrificados a los 315 días. 24 horas tras el sacrificio, se determinó el peso canal y rendimiento canal, se realizaron las medidas morfométricas (longitud de la canal, longitud de la pierna, espesor de la pierna, profundidad interna del pecho y perímetro máximo de la pierna), se calcularon los siguientes índices: índice de compacidad de la canal e índice longitudinal transversal de la pierna y se realizó el despiece de los principales cortes comerciales. Los animales de la raza Mirandesa presentaron un peso vivo de 293,7 kg, un peso canal de 152 kg y un rendimiento canal de 60,5 %. En relación a las medidas morfométricas, la raza Mirandesa mostró una longitud de canal de 110 cm, una longitud de pierna de 69 cm y un perímetro de pierna de 89,8 cm. Los valores para el índice de compacidad de la canal y el índice longitudinal transversal de la pierna fueron de 1,4 y 3,7, respectivamente. Con respecto al quinto cuarto, la piel presentó los mayores porcentajes seguida de la cabeza y pies. Finalmente, la composición de las canales de la raza Mirandesa fue: 74,9 % de carne, 18,1 % de hueso y 7,0 % de grasa.
- Social work as a bureaucratic professional labour: an empirical analysis in non-profit organizatíons in northern PortugalPublication . Caria, Telmo; Pereira, Fernando A.In the last decade and a half, a new perspective on sociological analysis of professional groups hás gradually emerged: professionalism and professionalization are no longer analysed as opposed to bureaucracies. In a previous article, we developed an analytical model in which we theorized a hybrid concept ofBureaucratic Professional Work (BPW), based on a theoretical hypothesis of association between various organizational forms (divisional bureaucracies, professional bureaucracies, neo-bureaucracies and post-bureaucracies) and different types ofprofessional work m social work. Structured interviews were conducted with 63 social work professionals who work in 35 non-profit organizations of social services in northem Portugal. We questioned how these professionals perceive their own work in relation to the levei of contrai and centralization of decisions, the routine of procedures and the predictability ofresults. We also study how social constraints, the tasks performed and work in multidisciplinary teams vary according to the type of BPW. This allows us to detail the modalities of the BPW and set out exploratory hypotheses for other more extensive quantitative studies as well as complementary studies of a qualitative nature.
- A feasibility cachaca type recognition using computer vision and pattern recognitionPublication . Rodrigues, Bruno Urbano; Soares, Anderson da Silva; Costa, Ronaldo Martins da; Van Baalen, J.; Salvini, Rogério Lopes; Silva, Flávio Alves da; Caliari, Márcio; Cardoso, Karla Cristina Rodrigues; Ribeiro, Tânia Isabel Monteiro; Delbem, A.C.B.; Federson, F.M.; Coelho, C.J.; Laureano, G.T.; Lima, T.W.Brazilian rum (also known as cachaça) is the third most commonly consumed distilled alcoholic drink in the world, with approximately 2.5 billion liters produced each year. It is a traditional drink with refined features and a delicate aroma that is produced mainly in Brazil but consumed in many countries. It can be aged in various types of wood for 1-3 years, which adds aroma and a distinctive flavor with different characteristics that affect the price. A research challenge is to develop a cheap automatic recognition system that inspects the finished product for the wood type and the aging time of its production. Some classical methods use chemical analysis, but this approach requires relatively expensive laboratory equipment. By contrast, the system proposed in this paper captures image signals from samples and uses an intelligent classification technique to recognize the wood type and the aging time. The classification system uses an ensemble of classifiers obtained from different wavelet decompositions. Each classifier is obtained with different wavelet transform settings. We compared the proposed approach with classical methods based on chemical features. We analyzed 105 samples that had been aged for 3 years and we showed that the proposed solution could automatically recognize wood types and the aging time with an accuracy up to 100.00% and 85.71% respectively, and our method is also cheaper.
- Application of bioelectrical impedance analysis in prediction of light kid carcass and muscle chemical compositionPublication . Silva, Severiano; Afonso, João; Monteiro, António; Morais, Reis; Cabo, Ângelo D.; Batista, Ana Cristina Beviláqua; Guedes, Cristina M.; Teixeira, AlfredoCarcass data were collected from 24 kids (average live weight of 12.5±5.5 kg; range 4.5 to 22.4 kg) of Jarmelista Portuguese native breed, to evaluate bioelectrical impedance analysis (BIA) as a technique for prediction of light kid carcass and muscle chemical composition. Resistance (Rs, Ω) and reactance (Xc, Ω), were measured in the cold carcasses with a single frequency bioelectrical impedance analyzer and, together with impedance (Z, Ω), two electrical volume measurements (VolA and VolB, cm2/Ω), carcass cold weight (CCW), carcass compactness and several carcass linear measurements were fitted as independent variables to predict carcass composition by stepwise regression analysis. The amount of variation explained by VolA and VolB only reached a significant level (P<0.01 and P<0.05, respectively) for muscle weight, moisture, protein and fat-free soft tissue content, even so with low accuracy, with VolA providing the best results (0.326⩽R 2⩽0.366). Quite differently, individual BIA parameters (Rs, Xc and Z) explained a very large amount of variation in dissectible carcass fat weight (0.814⩽R 2⩽0.862; P<0.01). These individual BIA parameters also explained a large amount of variation in subcutaneous and intermuscular fat weights (respectively 0.749⩽R 2⩽0.793 and 0.718⩽R 2⩽0.760; P<0.01), and in muscle chemical fat weight (0.663⩽R 2⩽0.684; P<0.01). Still significant but much lower was the variation in muscle, moisture, protein and fat-free soft tissue weights (0.344⩽R 2⩽0.393; P<0.01) explained by BIA parameters. Still, the best models for estimation of muscle, moisture, protein and fat-free soft tissue weights included Rs in addition to CCW, and accounted for 97.1% to 99.8% (P<0.01) of the variation observed, with CCW by itself accounting for 97.0% to 99.6% (P<0.01) of that variation. Resistance was the only independent variable selected for the best model predicting subcutaneous fat weight. It was also selected for the best models predicting carcass fat weight (combined with carcass length, CL; R 2=0.943; P<0.01) and intermuscular fat weight (combined with CCW; R 2=0.945; P<0.01). The best model predicting muscle chemical fat weight combined CCW and Z, explaining 85.6% (P<0.01) of the variation observed. These results indicate BIA as a useful tool for prediction of light kids' carcass composition.