Effects of Low-stress Weaning on Calf Growth Performance and Carcass Characteristics

The objective of this study was to compare the influence of two low-stress weaning methods with conventional weaning on post-weaning performance and carcass characteristics of beef steers

The Structure of Hydrogenase-2 from <i>Escherichia coli</i>:Implications for H₂ -Driven Proton Pumping

Under anaerobic conditions Escherichia coli is able to metabolize molecular hydrogen via the action of several [NiFe]-hydrogenase enzymes. Hydrogenase-2, which is typically present in cells at low levels during anaerobic respiration, is a periplasmic-facing membrane-bound complex that functions as a proton pump to convert energy from H2 oxidation into a proton gradient; consequently, its structure is of great interest. Empirically, the complex consists of a tightly-bound core catalytic module, comprising large (HybC) and small (HybO) subunits, which is attached to an Fe-S protein (HybA) and an integral membrane protein, HybB. To date, efforts to gain a more detailed picture have been thwarted by low native expression levels of hydrogenase-2 and the labile interaction between HybOC and HybA/HybB subunits. In this paper we describe a new over-expression system that has facilitated determination of high-resolution crystal structures of HybOC and, hence, a prediction of the quaternary structure of the HybOCAB complex

Revolutions from above: worker training as trasformismo in South Korea

While making very substantial changes to the population's working conditions, government strategies to foster economic development in South Korea have historically attempted to keep worker involvement, in terms of influence on the process, to a bare minimum. Applying the Gramscian concept of passive revolution, this article analyses governance mechanisms and production relations over a history of authoritarianism and up to the contemporary period of democratic reform. Trasformismo, which is a strategy of limited concessions, has been provided via vocational training for workers. Despite this attempt at inclusion, it is concluded that workers have not enjoyed full participation in negotiation for their welfare at any time in Korean history

Sparing effects of selenium and ascorbic acid on vitamin C and E in guinea pig tissues

BACKGROUND: Selenium (Se), vitamin C and vitamin E function as antioxidants within the body. In this study, we investigated the effects of reduced dietary Se and L-ascorbic acid (AA) on vitamin C and α-tocopherol (AT) status in guinea pig tissues. METHODS: Male Hartley guinea pigs were orally dosed with a marginal amount of AA and fed a diet deficient (Se-D/MC), marginal (Se-M/MC) or normal (Se-N/MC) in Se. An additional diet group (Se-N/NC) was fed normal Se and dosed with a normal amount of AA. Guinea pigs were killed after 5 or 12 weeks on the experimental diets at 24 and 48 hours post AA dosing. RESULTS: Liver Se-dependent glutathione peroxidase activity was decreased (P < 0.05) in guinea pigs fed Se or AA restricted diets. Plasma total glutathione concentrations were unaffected (P > 0.05) by reduction in dietary Se or AA. All tissues examined showed a decrease (P < 0.05) in AA content in Se-N/MC compared to Se-N/NC guinea pigs. Kidney, testis, muscle and spleen showed a decreasing trend (P < 0.05) in AA content with decreasing Se in the diet. Dehydroascorbic acid concentrations were decreased (P < 0.05) in several tissues with reduction in dietary Se (heart and spleen) or AA (liver, heart, kidney, muscle and spleen). At week 12, combined dietary restriction of Se and AA decreased AT concentrations in most tissues. In addition, restriction of Se (liver, heart and spleen) and AA (liver, kidney and spleen) separately also reduced AT in tissues. CONCLUSION: Together, these data demonstrate sparing effects of Se and AA on vitamin C and AT in guinea pig tissues

Development Discourse and Practice: Alternatives and New Directions from Postcolonial Perspectives

Development and aid programs, such as those aimed at promoting economic growth and prosperity in ‘Third World’ nations and transition economies, often arise out of Western and neo-liberal policy ideologies and practices. These programs may, in some cases, provide useful guidelines for restructuring institutional structures and governance mechanisms in nations that have long struggled with poverty, economic instability, health crises, and social and political turmoil. However, a growing number of critical voices are raising concerns over the guiding assumptions and inclusiveness of these policies and programs in their aims to promote economic development and social well-being in non-Western nations. We join these critical perspectives by way of postcolonial frameworks to highlight some of the problematic assumptions and oversights of development programs, while offering new alternatives and directions. By doing so, we contribute to organizational theorizing in a global context, as postcolonial insights provide much needed engagement with international aid policies and programs, as well as development organizations and institutions. To accomplish this, we offer a historical perspective on development, present a critique of the policies and practices guiding many aid programs, and conclude with suggestions emanating from postcoloniality

Dissolved organic carbon transformations and microbial community response to variations in recharge waters in a shallow carbonate aquifer

© 2016, The Author(s). In carbonate aquifers, dissolved organic carbon from the surface drives heterotrophic metabolism, generating CO2 in the subsurface. Although this has been a proposed mechanism for enhanced dissolution at the water table, respiration rates and their controlling factors have not been widely evaluated. This study investigates the composition and concentration of dissolved organic carbon (DOC) reaching the water table from different recharge pathways on a subtropical carbonate island using a combination of DOC concentration measurements, fluorescence and absorption characterisation. In addition, direct measurements of the microbial response to the differing water types were made. Interactions of rainfall with the vegetation, via throughfall and stemflow, increase the concentration of DOC. The highest DOC concentrations are associated with stemflow, overland recharge and dissolution hole waters which interact with bark lignin and exhibit strong terrestrial-derived characteristics. The groundwater samples exhibit the lowest concentrations of DOC and are comprised of refractory humic-like organic matter. The heterotrophic response seems to be controlled by the concentration of DOC in the sample. The terrestrially sourced humic-like matter in the stemflow and dissolution hole samples was highly labile, thus increasing the amount of biologically produced CO2 to drive dissolution. Based on the calculated respiration rates, microbial activity could enhance carbonate dissolution, increasing porosity generation by a maximum of 1%kyr−1 at the top of the freshwater lens