Características físicas dos ovos da perdiz vermelha (Alectoris rufa) criada em cativeiro

The objective of the present study was to evaluate the effects of female age (1, 2 and 3-year-old) and month of laying (March, April and May) on the physical characteristics of the red-legged partridge eggs reared in captivity. O objetivo do presente estudo foi avaliar os efeitos da idade das fêmeas (um, dois e três anos) e do mês de postura (março, abril e maio) sobre as características físicas dos ovos da perdiz vermelha (Alectoris rufa) criada em cativeiro. O peso (W), o comprimento máximo (L) e a largura máxima (B) de 2878 ovos foram determinados diretamente, enquanto o índice de forma (B/L), o volume (V) e a superfície (S) foram calculados com base nos parâmetros determinados diretamente. A análise mostrou diferenças significativas (P0,05). Observaram-se diferenças significativas (P<0,01) na largura máxima e no índice de forma do ovo entre as diferentes classes de idades, com valores mais elevados nas fêmeas mais velhas e no período de postura mais tardio. O volume dos ovos estimados por meio de V1 = 0,51LB2 e V2=0,913W foi afetado significativamente (P<0,01) pela idade e pelo mês de postura, bem como as áreas, S1=4.835W0,662, S2=4,951V10,666 e S3=4,951V20,666, as quais apresentaram os mesmos efeitos. Palavras-chave: perdiz vermelha, Alectoris rufa, características dos ovo

Assessing foraging strategies of herbivores in Mediterranean oak woodlands: a review of key issues and selected methodologies.

Montados are agro-silvo-pastoral ecosystems, typical of the Southwest Iberian Peninsula, of high socio-economic and conservation importance,where grazing is a dominant activity. Montados are characterized by na open tree canopy of Quercus sp. and a diverse undercover of shrubs and grasslands that constitute the plant food resources for grazing animals. Plant food resources of Montados are highly variable, both spatially and seasonally, in quantity and quality. Reliable and easy to use methods to monitor grazing are necessary to allow proper understanding of foraging strategies of grazing animals and to set sustainable grazing management. We describe the main characteristics of the plant food resources available for grazing animals, striking its variability, and revise the potential of using N-alkanes and saliva

CVD diamond coated silicon nitride self-mated systems : tribological behaviour under high loads

Friction and wear behaviour of self-mated chemical vapour deposited (CVD) diamond films coating silicon nitride ceramics (Si3N4) were investigated in ambient atmosphere. The tribological tests were conducted in a reciprocal motion ball-on-flat type tribometer under applied normal loads up to 80 N (~10 GPa). Several characterisation techniques - including scanning electron microscopy (SEM), atomic force microscopy (AFM) and micro-Raman studies - were used in order to assess the quality, stress state and wear resistance of the coatings. In addition, a novel method is presented to estimate the wear coefficient of the diamond coated flat specimens from AFM and optical microscopy (OM) observations of the wear tracks

Progress in Identifying High Nature Value Montados: Impacts of Grazing on Hardwood Rangeland Biodiversity

Due to their complex structure and traditional low-intensity management, Portuguese oak woodland rangelands known as montados are often considered high nature value (HNV) farming systems, and as such, they may be deemed eligible for subsidies and incentives by governmental and nongovernmental agencies. Too little is known about how the HNV concept might be applied to conserve complex silvopastoral systems. These systems, due to their structural and functional complexity at multiple scales, tend to support high levels of biodiversity. Montados are in sharp decline as a result of the rapid specialization of land management that, through simplification, undermines multifunctionality. Understanding how changes in management influence these systems and their biodiversity is needed for prioritizing conservation efforts and for ensuring they remain HNV systems. On the basis of a field survey in 58 plots distributed among 29 paddocks on 17 farms, we conducted an integrated analysis of the relationship between grazing intensity and biodiversity in montados of similar biophysical and structural characteristics. Data on management were obtained through interviews, and biodiversity data (vegetation, macrofungi, birds, herpetofauna) were obtained through specific field protocols. Additional spatial data, such as soil characteristics, slope, land cover, and linear landscape elements, were also analyzed. The results show no overall biodiversity variation as a result of different management practices. However, different groups of species react differently to specific management practices, and within a pasture, grazing impacts are heterogenous. In low grazing intensity plots, macrofungi species richness was found to be higher, while bird species richness was lower. Using tree regeneration as proxy for montado sustainability, results show less tree regeneration in areas with higher forage quality and more intense grazing. Pathways for future progress are proposed, including creating areas within a paddock that attract grazing away from where regeneration is desired

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02