Ground-cover systems in non-irrigated olive orchards

Currently, in NE Portugal, we are advising farmers to adopt ground-cover systems in olive orchards instead of tillage. Most of soils are on steep slopes and have very low organic matter content (Arrobas and Rodrigues, 2002). This consequently creates huge problems for soil conservation. However, we need strong arguments to convince the farmers. Tillage in a very old and ingrained practice; it is easy, pleasant and in some ways it works. Alternative management systems, such as the use of herbicides or cover crops, need a high degree of technical expertise. Ground-cover systems affect crop growth and yields by influencing weed competition, water use efficiency, nutrient uptake, soil fertility and soil conservation. In order to evaluate the multiple aspects of soil management systems in olive groves two field experiments have been conducted since October 2001 in NE Portugal. In this abstract olive yields and the increase in trunk circumference are presented

Testing the interaction of dark energy to dark matter through the analysis of virial relaxation of clusters Abell Clusters A586 and A1689 using realistic density profiles

Interaction between dark energy and dark matter is probed through deviation from the virial equilibrium for two relaxed clusters: A586 and A1689. The evaluation of the virial equilibrium is performed using realistic density profiles. The virial ratios found for the more realistic density profiles are consistent with the absence of interaction.Comment: 16pp 1 fig; accepted by GeR

Estudo anatômico da veia renal esquerda de cadáveres humanos brasileiros

O estudo das variações anatômicas da veia renal esquerda (VRE) é matéria de importância na realização das anastomoses para o tratamento cirúrgico da hipertensão portal, estudos radiológicos e para as nefrectomias de doadores de transplante renal. Trata-se de um estudo observacional transversal e retrospectivo, cujo objetivo foi identificar e avaliar as variações anatômicas da VRE em cadáveres. Um total de 34 cadáveres foi analisado (24 do sexo masculino, 10 do sexo feminino) sob os seguintes aspectos: número de tributárias renais, número de veias renais acessórias, posição em relação à aorta abdominal (Ao) e à artéria renal esquerda (ARE) e comprimento da VRE. A VRE era única em 91,1% (n=31) dos casos e dupla em 8,9% (n=3). Observou-se um caso de VRE circum-aórtica. Dos 34 casos estudados, 55,8% (n=19) apresentavam duas tributárias, que se uniam para formar a VRE principal, 14,7% (n=5) apresentavam três tributárias e, em 29,4% (n=10), elas eram ausentes ( quando a VRE originase diretamente do rim, sem que fossem visualizadas, no hilo, tributárias renais, que contribuíssem para a sua formação). A veia renoazigolombar esteve presente em 26,4%, n=9 (23,5%:única; 2,9%: dupla). A veia testicular / ovárica era única em 85,2% (n=29) e dupla em 8,8% (n=3).Em dois casos, não pôde ser estudada. Quanto à posição em relação à Ao e à ARE, a VRE encontrava-se predominantemente na topografia anterior, com variações percentuais de 44,5% a 96,5%, dependendo se a ARE era única, dupla ou tripla. O comprimento médio foi de 5,4cm, variando de 2,2cm a 8,0cm. Conclui-se, no presente estudo, que as tributárias renais foram mais freqüentes em número de duas; a veia renoazigolombar esteve presente em freqüência inferior à da literatura; a veia testicular / ovárica foi mais freqüente na forma única; a posição mais freqüente em relação à Ao e à ARE foi a anterior e o comprimento médio da VRE concordou com apenas duas das publicações onde tal parâmetro foi avaliado.The study of the anatomical variations of the left renal vein (LRV) is an important subject to the accomplishment of the anastomosis to the surgical treatment of the portal hypertension, to the radiological studies and to the nephrectomies of the renal transplantation donors. This is a retrospective; transversal and observational study whose objective was to identify and study the anatomical variations of the LRV in cadavers. We have analyzed 34 cadavers (24 male; 10 female) under the following aspects: number of the tributaries renaIs, number of the accessories renals, position in relation to the abdominal aorta (Ao) and in relation to the left renal artery (LRA) and length of the LRV. The LRV was single in 91,1% of the cases and double in 8,9% (n=3). It was observed one case of circumaortic LRV. Among the 34 studied cases, 55,8% (n=19) showed two tributaries which joined to form a principal LRV, 14,7 % (n=5) showed three tributaries and in 29,4% (n=10) they were absent (to mean when the LRV is originated directly from left kidney without be seen tributaries, on the hile, that contribute to its formation). The renolumbar vein was present in 26,4% (n (23,5% single; 2,9% double.). The testicular / ovarian vein was single in 85,2% (n=29) and double in 8,8% (n3). In two cases it could not be studied. In relation to the position of the Ao and to the LRA, the LRV is basically found in the anterior topography with percent variations of 44,5% to 96,5%, depending if the LRA was single, double, or triple. The average length was of 5,4 cm varying from 2,2 cm to 8,0 cm. In this study we came to the conclusion that the renal tributaries were more frequently two; the renolumbar vein was present in a frequency inferior to the one in the literature; the testicular/ovarian was more frequent in the single form; the more frequent position in relation to the Ao and to the LRA was the anterior and average length of the LRV was in accordance only with two of the publications in which this parameter was analyzed