Comparing Soil Compaction under Different Grazing Systems with a Virgin Forest Soil to Determine Optimal Stocking Rates

The understanding of how soil physical properties respond to differing grazing practices may help explain the main causes of pasture degradation. Soil compaction has been shown to be a main degradation form of soil and the knowledge of techniques to quantify and rectify this are necessary to maintain optimal yields. This research aims to measure the rupture lines of red yellow latossol under differing pasture grazing practices compared to cropping and a natural forest. With this information it is aimed to calculate the correction factor for stocking rates and traffic of tillage tools. The differing soil management practices examined was, pasture grazed by sheep, and dairy cattle, a maize crop in no tillage cover-crop system and a natural forest. To quantify the soil physical changes, the direct shear test was used, which calculated the resultant force of a load. The resultant forces of the natural forest were compared against pasture systems and crop system, and a correction factor for stocking rates was calculated. The samples of Red yellow Latossol were equilibrated in the matrix potential (ψ): -6 kPa. In the shear test, the normal stress used was the 450kPa. The correction factor (CF) indicates whether the soil has structural degradation compared to natural forest. Values less than 1 indicated soil degradation. The pastures grazed by sheep and dairy cattle had values observed to be less than 1, excessive loads at high soil moisture may be attributed to this soil structural deformation. For these systems, grazing management and stocking rates should be corrected. The correction factor gives an indication of the magnitude of management change that is required (i.e. the stocking rate decreased). The crop area was found to have no soil strength issues, using the stress test

A mixed-methods approach

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Phytochemical Composition of Extractives in the Inner Cork Layer of Cork Oaks with Low and Moderate Coraebus undatus Attack

The beetle Coraebus undatus, during its larval stage feeds, and excavates galleries on the cork-generating layer of Quercus suber L. trees, seriously affecting the cork quality with significant economic losses for the cork industry. This work compared the composition of the extracts present in the innermost cork layers (the belly) of cork planks from Q. suber trees with low and moderate C. undatus attack in one stand. The total extractives in the inner cork layer from trees with moderate and low C. undatus attacks were similar (on average 22% of the cork mass) with a high proportion of polar compounds (91% of the total extractives). The chemical composition of the inner cork lipophilic extractives was the same in trees infested and free of larvae, with triterpenes as the most abundant family accounting for 77% of all the compounds, predominantly friedeline. The hydrophilic extractives differed on the levels of phenolic compounds, with higher levels in the inner cork extracts of samples from trees with low attack (90.0 mg GAE g1 vs. 59.0 mg GAE g1 of inner cork mass) The potential toxic activity of phenolic compounds may have a role in decreasing the larval feedinginfo:eu-repo/semantics/publishedVersio

um instrumento para captar como a pandemia da COVID-19 afeta as pessoas que vivem com paralisia cerebral

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Rank concordance of polygenic indices

Polygenic indices (PGIs) are increasingly used to identify individuals at risk of developing disease and are advocated as screening tools for personalized medicine and education. Here we empirically assess rank concordance between PGIs created with different construction methods and discovery samples, focusing on cardiovascular disease and educational attainment. We find Spearman rank correlations between 0.17 and 0.93 for cardiovascular disease, and 0.40 and 0.83 for educational attainment, indicating highly unstable rankings across different PGIs for the same trait. Potential consequences for personalized medicine and gene–environment (G × E) interplay are illustrated using data from the UK Biobank. Simulations show how rank discordance mainly derives from a limited discovery sample size and reveal a tight link between the explained variance of a PGI and its ranking precision. We conclude that PGI-based ranking is highly dependent on PGI choice, such that current PGIs do not have the desired precision to be used routinely for personalized intervention.</p

Variabilidade genética em amostras de melancia, Citrullus lanatus (Thunb.) Matsum & Nakai, coletadas em seis municípios do semi-árido do nordeste brasileiro

Forty-two watermelon seed samples were collected from six counties in the dry areas of the Northeast Brazil, particularly the states of Pernambuco, Bahia and Piauí, between 1985 and 1987. The samples were either from the farmer’s stock or from fruits of volunteer watermelon plants grown in the Experiment Stations of EMBRAPA in Petrolina, Pernambuco. Some accesses were evaluated for powdery mildiew and papaya ring spot virus-watermelon strain (PRSV-w) in 1987, 1988 and 1989. In 1987, in a field experiment, some seed samples were evaluated for fruit and plant characters (prolificacy, yield per plant, fruit shape and weight, flesh and seed color). Despite the limited area covered and few analysis performed, it was detected genetic variability for prolificacy, yield per plant, fruit shape and weight, flesh and seed color, resistance to powdery mildew and to PRSV-w. The promising accessions found can be used in crosses and selection programs in order to obtain adapted cultivars for the  irrigated conditions of Northeast Brazil.Foram coletadas 42 amostras de acessos de melancia provenientes de algumas comunidades de seis municípios do semi-árido nordestino, envolvendo os estados de Pernambuco, Bahia e Piauí, entre os anos de 1985 e 1987. Foram coletadas sementes do estoque de plantio de pequenos produtores e dos frutos de plantas voluntárias encontradas nas Estações Experimentais da EMBRAPA, em Petrolina, Pernambuco. Amostras de sementes de alguns acessos foram avaliadas nos anos de 1987, 1988 e1989 quanto à resistência ao oídio e ao vírus WMV-1, hoje PRSV-w. Em 1987, em parcelas únicas, avaliaram-se alguns acessos quanto à prolificidade, tamanho e formato do fruto, produtividade por planta, cor da polpa e da semente. Apesar da abrangência limitada da área de coleta e da análise de poucos caracteres, foi detectada variabilidade genética para prolificidade, produção por planta, peso e formato do fruto, cor da polpa e da semente. Os acessos promissores poderão ser utilizados em programas de cruzamento e seleção, com vistas à obtenção de cultivares de melancia adaptadas às condições irrigadas do nordeste brasileiro

Effect of variable levels of dietary cholesterol and plant sterols on the growth performance and bone metabolism in gilthead seabream (Sparus aurata) juveniles

Cholesterol is found in all animal tissues and is an important component of biological cell membranes with functions such as precursor to bile acids, hormones and vitamins. Fish meal and fish oil are cholesterol-rich ingredients. Replacement of these marine-derived ingredients by plant proteins and vegetable oils tends to reduce dietary cholesterol levels

Effect of Headgroup on DNA−Cationic Surfactant Interactions

The interaction behavior of DNA with different types of hydroxylated cationic surfactants has been studied. Attention was directed to how the introduction of hydroxyl substituents at the headgroup of the cationic surfactants affects the compaction of DNA. The DNA−cationic surfactant interaction was investigated at different charge ratios by several methods like UV melting, ethidium bromide exclusion, and gel electrophoresis. Studies show that there is a discrete transition in the DNA chain from extended coils (free chain) to a compact form and that this transition does not depend substantially on the architecture of the headgroup. However, the accessibility of DNA to ethidium bromide is preserved to a significantly larger extent for the more hydrophilic surfactants. This was discussed in terms of surfactant packing. Observations are interpreted to reflect that the surfactants with more substituents have a larger headgroup and therefore form smaller micellar aggregates; these higher curvature aggregates lead to a less efficient, “patch-like” coverage of DNA. The more hydrophilic surfactants also presented a significantly lower cytotoxicity, which is important for biotechnological applications

Synergistic activity of cold pressed seed oils from Indian neem (Azadirachta indica), karanja (Pongamia glabra) and aloe vera gel (Aloe barbadensis) in a cosmeceutical moisturizer

The increased interest and knowledge on the beneficial activity of plants and their compounds in human health have contributed to the development of several drugs, widely used in clinical practice worldwideinfo:eu-repo/semantics/publishedVersio