Universidade Federal de Viçosa

About: Universidade Federal de Viçosa is a education organization based out in Viçosa, Brazil. It is known for research contribution in the topics: Population & Dry matter. The organization has 16012 authors who have published 26711 publications receiving 353416 citations.

Enzymatic hydrolysis of lignocellulosic biomass: converting food waste in valuable products

Abstract: Second generation ethanol production has great potential to be a sustainable reality, especially in Brazil due to the large quantity of sugarcane bagasse encountered as industrial waste Moreover, this process does not require that food crops are converted into biofuels Biomass hydrolysis continues to be a bottleneck of the overall process due to the high costs of enzyme production Therefore, efforts have been taken to make the process more cost-effective with regards to the discover of more effective enzymes New sources of enzymes are continuously encountered and several strategies of enzyme prospection and production have been studied The fermentation step is also an area of interest for biochemical alteration since pentoses are not effectively fermented to ethanol via traditional methods

Sublethal exposure, insecticide resistance, and community stress

Abstract: Insecticides are an invaluable pest management tool and anthropogenic stressors of widespread environmental occurrence that are subject to biased perceptions based on the targeted application, market value of use, and regulatory requirements As a result, short-term and simplistic efforts focusing on lethal effects toward individual species and populations prevail Holistic and comprehensive studies exploring rather common sublethal insecticide exposures are rare, particularly considering their potential role in structuring populations and communities in diverse environmental settings and potentially interfering in a range of ecological interactions Studies on insecticide resistance, for example, do not go beyond population-based studies, disregarding temporal and spatial effects in the associated community, and rarely considering the whole of sublethal exposure Some of these knowledge gaps are here recognized and explored

Deforestation and climate feedbacks threaten the ecological integrity of south–southeastern Amazonia

Abstract: A mosaic of protected areas, including indigenous lands, sustainable-use production forests and reserves and strictly protected forests is the cornerstone of conservation in the Amazon, with almost 50 per cent of the region now protected. However, recent research indicates that isolation from direct deforestation or degradation may not be sufficient to maintain the ecological integrity of Amazon forests over the next several decades. Large-scale changes in fire and drought regimes occurring as a result of deforestation and greenhouse gas increases may result in forest degradation, regardless of protected status. How severe or widespread these feedbacks will be is uncertain, but the arc of deforestation in south–southeastern Amazonia appears to be particularly vulnerable owing to high current deforestation rates and ecological sensitivity to climate change. Maintaining forest ecosystem integrity may require significant strengthening of forest conservation on private property, which can in part be accomplished by leveraging existing policy mechanisms.

Energy expenditure: components and evaluation methods.

Abstract: Introduction: The determination of energy expenditure, considering the physical activity level and health status, is very important to adjust the individuals’ nutritional supply. Energy expenditure can be determined by using indirect calorimetry, bioelectrical impedance, doubly labeled water, predictive equations, among others. All these methods have been used in clinical and research areas. However, considering the inconsistence in several research results, there is no consensus yet about the applicability of many of these methods. Objectives: The aim of this review is to describe the components of energy expenditure and the methods for its determination and estimation, summarizing their main advantages and limitations. Results and discussion: Indirect calorimetry and doubly labeled water are considered more accurate methods, but expensive. On the other hand, even though other methods present limitations, they are convenient and less expensive, and can be used with some caution. (Nutr Hosp. 2011;26:430-440) DOI:10.3305/nh.2011.26.3.5181

Charge-Transfer Mechanism in Graphene-Enhanced Raman Scattering

Abstract: In the chemical enhancement mechanism for Raman scattering, the two types of charge-transfer models, the excited-state and the ground-state charge-transfer mechanisms, present the different depende...