Classification, characterisation and strategies for improvement of cattle and sheep pasture systems in marginal areas of Southern Chile

Pasture-based livestock systems in farms with medium or low size are especially important in less favored areas and are valuable for society. For these systems to survive, it is necessary to obtain an acceptable level of productivity and ensure commercialization of the products. This study was carried out in the district of Rio Ibáñez, General Carrera Province, in the XI (Aysén) Region of Chile. The sample consisted of 28 small-scale livestock farmers with dual-purpose cattle production; 16 of them also produced sheep for meat. The empirical data produced 55 variables which were subjected to multivariate analysis; three main components were obtained which explain 72.1 % of the variance. By cluster analysis it was obtained four groups with characteristics which varied by farm size, age and personal situation of farmers, farm management and farm profitability. The principal problems found are low productivity in the herds and the poor marketing channels of animals produced. In two groups, due to the low size and poor management, the profitability of the farms is very low and this may compromise their future. To improve production systems, the training and advice of farmers should be strengthened, investment should be supported, especially for young people, and the farmer partnership should be promoted. There is also a need to diversify the families' sources of income (sale of other farm products or handicrafts and touristic activities).Ministerio de Economía de Chile Innova-CORFO Project 11 NTEC 1279

Classification, characterisation and strategies for improvement of cattle and sheep pasture systems in marginal areas of Southern Chile

Pasture-based livestock systems in farms with medium or low size are especially important in less favored areas and are valuable for society. For these systems to survive, it is necessary to obtain an acceptable level of productivity and ensure commercialization of the products. This study was carried out in the district of Rio Ibáñez, General Carrera Province, in the XI (Aysén) Region of Chile. The sample consisted of 28 small-scale livestock farmers with dual-purpose cattle production; 16 of them also produced sheep for meat. The empirical data produced 55 variables which were subjected to multivariate analysis; three main components were obtained which explain 72.1 % of the variance. By cluster analysis it was obtained four groups with characteristics which varied by farm size, age and personal situation of farmers, farm management and farm profitability. The principal problems found are low productivity in the herds and the poor marketing channels of animals produced. In two groups, due to the low size and poor management, the profitability of the farms is very low and this may compromise their future. To improve production systems, the training and advice of farmers should be strengthened, investment should be supported, especially for young people, and the farmer partnership should be promoted. There is also a need to diversify the families' sources of income (sale of other farm products or handicrafts and touristic activities).Ministerio de Economía de Chile Innova-CORFO Project 11 NTEC 1279

Estuarine hydrodynamic patterns and hydrokinetic energy production: The Douro estuary case study

Influenced by both marine and river flows, estuaries can present a high potential for hydrokinetic energy exploitation. In this study, the hydrokinetic energy production in the Douro estuary was evaluated through hydrodynamic numerical modelling. The model analysed the tide and river flow, reproduced the combined effects of these two factors on the main current velocity patterns, and identified the estuarine locations with the highest potential for energy exploitation. Given the river?s high variability caused by the precipitation patterns in the hydrographic basin area and the river?s torrential regime, several discharge scenarios were explored, combining spring and neap tides, and high and low river flows. The results revealed that the region with the highest potential is located in the upper part of the estuary, where the highest-velocity currents were achieved for mid-ebb tide conditions and strong river flows. It was also found that tides reinforce the hydrokinetic energy production during ebb tide, although they are not strong enough to produce high values of hydrokinetic energy, being the river flow the main forcing. This work demonstrates the relevance of choosing parametrized magnitudes that are not dependent on a specific equipment, as well as the importance of a proper characterization of the estuarine hydrodynamic patterns needed to optimize the hydrokinetic energy exploitation. ? 2021 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Um esquema de elementos finitos para ondas dispersivas unidireccionais

Apresenta-se um Método de Elementos Finitos (MEF) com uma formulação de Petrov-Galerkin para a resolução numérica da equação Regularized Long Wave (RLW). O esquema proposto recorre à discretização por elementos finitos no espaço e no tempo. Introduz-se uma correcção da dispersão numérica bem como um mecanismo dissipativo altamente selectivo, através de termos adicionais upwind nas funções de peso. A integração no tempo recorre a um esquema do tipo predictor-corrector com três passos correctores. A formulação permite uma precisão de quarta ordem na forma linear, sendo condicionalmente estável. Ilustra-se a apresentação com três experiências numéricas, cujos resultados são comparados com casos similares presentes na literatura: propagação de uma onda solitária; colisão de duas ondas solitárias; propagação e break-up de um impulso de Maxwell. Conclui-se que o esquema possui boas propriedades conservativas e elevada precisão

Conjugated linoleic acid content in milk of Chilean Black Friesian cows under pasture conditions and supplemented with canola seed (Brassica napus) concentrate

At present, there is limited and contradictory information about the effects of the use of canola (Brassica napus) seed as supplement on the contents of conjugated linoleic acid (CLA) in milk of grazing cows. The objective of this study was to evaluate the effect of a dietary supplement with canola seed on the production and composition of milk, and CLA concentration in Chilean Black Friesian cows under pasture conditions. Three experiments were done. Experiment 1: control group was fed 5 kg d–1 of commercial concentrate without canola (0-TC1) and treatment group that was fed 3.75 kg of commercial concentrate plus 1.16 kg of whole canola seed (1.16-TC1). Experiment 2: Control group was fed 8 kg d–1 commercial concentrate without canola (0-TC2) and treatment group that was fed 6.2 kg of commercial concentrate plus 1.2 kg of ground canola seed (1.2-TC2). Experiment 3: control group was fed 6 kg d–1 commercial concentrate without canola (0-TC3) and treatment group was fed 6 kg of commercial concentrate with 20% of whole canola seed (1.2 kg d–1, 1.2-TC3). The duration of each experiment was 60 days. No differences in milk production and quality were observed among the experimental groups in every assay. The CLA isomers trans-10, cis-12 and cis-10, cis-12 were higher than those normally found in the scientific literature. There was no effect of the inclusion of canola seed on total CLA content or the content of cis-9, trans-11, trans-10, cis-12 and cis-10, cis-12 isomers

Analysis of DDM into Gamma Radiation

We are interested in the purpose of a dipolar fermionic particle as a viable candidate of Dark Matter (DDM). Then, we study the annihilation of dark matter into photons, considering it as a neutral particle with non-vanishing magnetic (M) and electric (D) dipolar moments. The total annihilation cross section σ(χ → γ) is computed by starting from a general form of coupling χγ in a framework beyond to Standard Model (BSM). We found that candidates with O(mχ )∽102GeV, D≈10−16 e cm are required in order to satisfy the current cosmic relic density

Assessment of a Sand Spit Morphodynamics Under Extreme Flood Events

&lt;p&gt;Spits are landforms that present a complex morphology, which depends on currents, waves, sediment transport, tidal range and anthropic-induced changes. Their position and shape is subject to extreme events like flood river discharges and storms. They can also respond to processes that take place at larger time scales, as plate tectonics, sea level rise or even climatological patterns with teleconnections all over the world, as the well know North Atlantic Oscillation (NAO) or El Ni&amp;#241;o-Southern Oscillation (ENSO). This is the case of the Douro river mouth sand spit located on the northern coast of Portugal. This naturally dynamic sand spit, which has moved landwards over the past decades, has caused frequent nuisance to navigation, affecting width and depth of the navigation channel. Therefore, a breakwater was constructed in an attempt to stabilise the sand spit and the estuary inlet.&lt;/p&gt;&lt;p&gt;Validated hydrodynamic numerical models (openTELEMAC-MASCARET and Delft3D) of the Douro river estuary have demonstrated ability to accurately describe the estuarine hydrodynamic patterns and water elevation under extreme flood conditions. Model results showed that for higher river flow discharges the sand spit is partially inundated.&lt;/p&gt;&lt;p&gt;In this work a morphodynamic model (Delft3D) of the estuary was implemented to assess both the morphodynamics of the sand spit under extreme events, including the effect of sea level rise due to climate change, and the variation of extreme water levels along the estuary due to spit erosional processes that can occur during flood events.&lt;/p&gt;&lt;p&gt;Preliminary results show that the sand spit will be locally eroded for the higher river flood discharges, forming a two-secondary-channels system, with one channel located near the breakwater&amp;#8217;s southern extremity and the other, narrower, near the south bank. Associated with these two channels, two depositional bars will be formed in front of the channels at the coastal platform. However, the inner immersed sand spit will be suffering a sedimentation process for all of the simulated scenarios. This way, neither the river mouth discharge conditions nor the water levels inside the estuary will suffer significant changes according to the simulated scenarios.&lt;/p&gt;&lt;p&gt;These results will be complemented with further analyses considering the sediment size influence, tidal level, storm surge, sea level rise and river flood discharges.&lt;/p&gt;&lt;p&gt;Acknowledgements: To the Strategic Funding UIDB/04423/2020 and UIDP/04423/2020 (FCT and ERDF) and to the project EsCo-Ensembles (PTDC/ECI-EGC/30877/2017, NORTE 2020, Portugal 2020, ERDF and FCT). The authors also want to acknowledge the data provided by EDP and IH.&lt;/p&gt;</jats:p

Future estuarine circulation patterns characterization based on a hydrodynamic models ensemble

&lt;p&gt;Estuarine regions are strategically important from an environmental, economic, and social point of view. To reduce vulnerability and increase resilience, it is crucial to know their dynamics that usually are poorly understood. Numerical models have proven to be an appropriate tool to improve this knowledge and simulate scenarios for future conditions. However, as the modelling results may be inaccurate, the application of the ensembles technique can be very useful in reducing possible uncertainties. In the EsCo-Ensembles project, this technique is proposed to improve hydrodynamic predictions for two Portuguese estuaries: Douro and Minho.&lt;/p&gt;&lt;p&gt;Two already validated numerical models (openTELEMAC-MASCARET and Delft3D), which have demonstrated their ability to accurately describe estuarine hydrodynamic patterns and water elevation for river flow in normal and extreme conditions, were applied. Several scenarios for climate change effects were defined including river flood peak flows for the 100 and 1000 year return periods and sea level extreme values for RCPs 4.5 and 8.5 in 2100.&lt;/p&gt;&lt;p&gt;The results demonstrated a clear difference between the hydrodynamic behaviour of the two estuaries. Model outcomes for the Minho estuary, which is dominated by the tide and therefore by oceanographic conditions, show a pronounced effect of rising sea levels on estuarine hydrodynamics. Whereas, for the Douro estuary, which is heavily dominated by the river flow, the effect of the sea level rise is hardly noticeable during flood events.&lt;/p&gt;&lt;p&gt;These and further results of this ongoing project are expected to (i) provide a complete hydrodynamic characterization of the two estuaries; (ii) evaluate future trends; (iii) estimate the flood risks associated with extreme events and (iv) demonstrate that the combined use of different models reduces their uncertainty and increases the confidence and consistency of the forecasts.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Acknowledgements: &lt;/strong&gt;To the Strategic Funding UIDB/04423/2020 and UIDP/04423/2020 (FCT and ERDF) and to the project EsCo-Ensembles (PTDC/ECI-EGC/30877/2017, NORTE 2020, Portugal 2020, ERDF and FCT). The authors also want to acknowledge the data provided by EDP, IH and Confederaci&amp;#243;n Hidrogr&amp;#225;fica Mi&amp;#241;o-Sil.&lt;/p&gt;</jats:p

First Lattice Calculation of the Electromagnetic Operator Amplitude <pi0|Q+|K0>

We present the first lattice calculation of the matrix element of the electromagnetic operator , where Q+ = (Q_d e/16 pi^2)* (\bar s_L sigma{mu,nu} F{mu,nu} d_R + \bar s_R sigma{mu,nu} F{mu,nu} d_L). This matrix element plays an important role, since it contributes to enhance the CP violating part of the K_L -> pi0 e+ e- amplitude in supersymmetric extensions of the Standard Model.Comment: 12 pages, 3 figure