603 research outputs found
Influence of damaging and wilting red clover on lipid metabolism during ensiling and in vitro rumen incubation
This paper describes the relationship between protein-bound phenols in red clover, induced by different degrees of damaging before wilting and varying wilting duration, and in silo lipid metabolism. The ultimate effect of these changes on rumen biohydrogenation is the second focus of this paper For this experiment, red clover, damaged to different degrees (not damaged (ND), crushing or frozen/thawing (FT)) before wilting (4 or 24 h) was ensiled. Different degrees of damaging and wilting duration lead to differences in polyphenol oxidase (PPO) activity, measured as increase in protein-bound phenols. Treatment effects on fatty acid (FA) content and composition, lipid fractions (free FAs, membrane lipids (ML) and neutral fraction) and lipolysis were further studied in the silage. In FT, red clover lipolysis was markedly lower in the first days after ensiling, but this largely disappeared after 60 days of ensiling, regardless of wilting duration. This suggests an inhibition of plant lipases in FT silages. After 60 days of ensiling no differences in lipid fractions could be found between any of the treatments and differences in lipolysis were caused by reduced FA proportions in ML of wilted FT red clover Fresh, wilted (24 h) after damaging (ND or FT) and ensiled (4 or 60 days; wilted 24 h; ND or FT) red clover were also incubated in rumen fluid to study the biohydrogenation of C18:3n-3 and C18:2n-6 in vitro. Silages (both 60 days and to a lower degree 4 days) showed a lower biohydrogenation compared with fresh and wilted forages, regardless of damaging. This suggests that lipids in ensiled red clover were more protected, but this protection was not enhanced by a higher amount of protein-bound phenols in wilted FT compared with ND red clover The reduction of rumen microbial biohydrogenation with duration of red clover ensiling seems in contrast to what is expected, namely a higher biohydrogenation when a higher amount of FFA is present. This merits further investigation in relation to strategies to activate PPO toward the embedding of lipids in phenol protein complexes
Effect of tillage practices on the soil carbon dioxide flux during fall and spring seasons in a Mediterranean Vertisol
In this study, we assessed the effect of conventional tillage (CT), reduced (RT) and no tillage (NT) practices on the soil CO2 flux of a Mediterranean Vertisol in semi-arid Morocco. The measurements focused on the short term (0 to 96 h) soil CO2 fluxes measured directly after tillage during the fall and spring period. Soil temperature, moisture and soil strength were measured congruently to study their effect on the soil CO2 flux magnitude. Immediately after fall tillage, the CT showed the highest CO2 flux (4.9 g m-2 h-1); RT exhibited an intermediate value (2.1 g m-2 h-1) whereas the lowest flux (0.7 g m-2 h-1) was reported under NT. After spring tillage, similar but smaller impacts of the tillage practices on soil CO2 flux were reported with fluxes ranging from 1.8 g CO2 m-2 h-1 (CT) to less than 0.1 g CO2 m-2 h-1 (NT). Soil strength was significantly correlated with soil CO2 emission; whereas surface soil temperature and moisture were low correlated to the soil CO2 flux. The intensity of rainfall events before fall and spring tillage practices could explain the seasonal CO2 flux trends. The findings promote conservation tillage and more specifically no tillage practices to reduce CO2 losses within these Mediterranean agroecosystems. (Résumé d'auteur
Promoting Safe Mobility Among Elders by Increasing Awareness of Vehicle Modifications (EXECUTIVE SUMMARY)
This research project looks at one strategy to address the safety of older drivers, vehicular modifications. Specifically, a video demonstrating low-tech, low-cost features that may alleviate some driving challenges was produced to determine whether viewing the video would increase awareness of and motivation to use those features. Prochaska and DiClemente’s Transtheoretical Model of intentional behavioral change provides the theoretical framework for this study. This model posits five stages of change, a continuum over which the individual becomes more receptive to taking action
Changes in the chemical and mineralogical properties of Mt. Talang volcanic ash in West Sumatra during the initail weathering phase.
Eruptions from Talang volcano on 12 April 2005 distributed volcanic ash over portions of the Solok District of West Sumatra, Indonesia. Unleached and leached pristine volcanic ash were collected immediately after the eruption, and the third sample was collected after 2 years. The mineralogy and chemical properties of pristine volcanic ash and volcanic ash deposits that were weathered for 2 years from the 2005 eruption of Mt. Talang, Sumatra, were studied to characterize the volcanic ash, identify the primary minerals present, and determine its chemical properties. Results showed that the volcanic ash contained 30% noncrystalline minerals (or volcanic glass); the remaining ash is composed of crystalline minerals such as labradorite, hypersthene, augite, hornblende, olivine, opaque ferromagnetic minerals, and rock fragments. Notable differences in pH values were observed as the pH tended to become more acidic from the unleached, leached, and weathered volcanic ash, but the ash did not give much response to the sodium fluoride (NaF) test. Total sulfur gradually decreased from 3.28% in unleached ash to 1.93% after 2 years. Available phosphorus (P) in the unleached volcanic ash was 68 mg kg−1, and this value was decreased by 15 % after 2 years of being exposed to the atmosphere, while phosphate retention ranged between 52.8% and 66.8%. Cation exchange capacity (CEC) was low with the value of 10 cmolc kg−1 although base saturation was high, exceeding 75%. The low acid oxalate–extractable silicon (Si), aluminum (Al), and iron (Fe) values of 0.07%, 0.25% and 1.17%, respectively, show the scarcity of secondary amorphous compounds in the ash. Total elemental analysis indicated that no differences were found in total silica oxide (SiO2) content of all samples, with a value about 56%, and this volcanic ash can be classified as basaltic andesite. We observed that removal of chemical elements by leaching was large for calcium oxide (CaO), magnesium oxide (MgO), and sodium oxide (Na2O) as the values decreased in time. Solid-state 29Si and 27Al magic angle spinning (MAS) nuclear magnetic resonance (NMR) studies indicated that Al occurred in both tetrahedral and octahedral forms. Silicon was not present in the tetrahedral layer. An intense peak at −92 ppm was indicative of the presence of aluminosilicates
Evidence for a Complex Mosaic Genome Pattern in a Full-length Hepatitis C Virus Sequence
The genome of the hepatitis C virus (HCV) exhibits a high genetic variability. This remarkable heterogeneity is mainly attributed to the gradual accumulation of mutational changes, whereas the contribution of recombination events to the evolution of HCV remains controversial so far. While performing phylogenetic analyses including a large number of sequences deposited in the GenBank, we encountered a full-length HCV sequence (AY651061) that showed evidence for inter-subtype recombination and was, therefore, subjected to a detailed analysis of its molecular structure. The obtained results indicated that AY651061 does not represent a “simple” HCV 1c isolate, but a complex 1a/1c mosaic genome, showing five putative breakpoints in the core to NS3 regions. To our knowledge, this is the first report on a mosaic HCV full-length sequence with multiple breakpoints. The molecular structure of AY651061 is reminiscent of complex homologous recombinant variants occurring among other members of the flaviviridae family, e.g. GB virus C, dengue virus, and Japanese encephalitis virus. Our finding of a mosaic HCV sequence may have important implications for many fields of current HCV research which merit careful consideration
Community-Based Conservation: An Emerging Land Use at the Livestock-Wildlife Interface in Northern Kenya
In East Africa, an estimated 70% of wildlife populations are dispersed outside protected areas on community land. The way of life of the pastoralists, essentially support the thriving of wildlife. However, pastoralism is slowly transiting to more sedentary forms of livestock production. The region‘s wildlife populations future now largely depends on the conservation of habitats and migratory corridors on private and communally owned lands with competing land uses. Community wildlife conservancies are one of the approaches of decentralizing wildlife management and curbing biodiversity and habitat loss at the livestock-wildlife interface environments. Further, conservancies present an avenue for restoration of degraded grazing lands and improving pastoral livelihoods. This paper reviews the community-based conservation unfolding in northern Kenya using the case of Naibung’a Wildlife Conservancy in Laikipia County. Conservancies through land zoning and range rehabilitation have contributed to improved security of wildlife, people and their livestock. Conservancies’ success depends on continued investment in vegetation recovery, grazing management, livestock marketing and benefit sharing. The perceived threats facing conservancies are pasture scarcity, cattle rustling and human-wildlife conflicts. Conservation objectives and human livelihoods in Africa are closely interlinked and lessons learnt in Naibung’a Wildlife Conservancy could particularly be useful to other similar initiatives in Africa
Tillage system affects soil organic carbon storage and quality in Central Morocco
Stabilizing or improving soil organic carbon content is essential for sustainable crop production under changing climate conditions. Therefore, soil organic carbon research is gaining momentum in the Mediterranean basin. Our objective is to quantify effects of no tillage (NT) and conventional tillage (CT) on soil organic carbon stock (SOCs) in three soil types (Vertisol, Cambisol, and Luvisol) within Central Morocco. Chemical analyses were used to determine how tillage affected various humic substances. Our results showed that, after 5 years, surface horizon (0–30 cm) SOC stocks varied between tillage systems and with soil type. The SOCs was significantly higher in NT compared to CT (10% more in Vertisol and 8% more in Cambisol), but no significant difference was observed in the Luvisol. Average SOCs within the 0–30 cm depth was 29.35 and 27.36 Mg ha−1 under NT and CT, respectively. The highest SOCs (31.89 Mg ha−1) was found in Vertisols under NT. A comparison of humic substances showed that humic acids and humin were significantly higher under NT compared to CT, but fulvic acid concentrations were significantly lower. These studies confirm that NT does have beneficial effects on SOCs and quality in these soils
SARS-CoV2 (COVID-19) infection: is fetal surgery in times of national disasters reasonable?
Even though the global COVID‐19 pandemic may affect how medical care is delivered in general, most countries try to maintain steady access for women to routine pregnancy care, including fetal anomaly screening. This means that, also during this pandemic, fetal anomalies will be detected, and that discussions regarding invasive genetic testing and possibly fetal therapy will need to take place. For patients, concerns about Severe Acute Respiratory Syndrome‐Corona Virus 2 will add to the anxiety caused by the diagnosis of a serious fetal anomaly. Yet, also for fetal medicine teams the situation gets more complex as they must weigh up the risks and benefits to the fetus as well as the mother, while managing a changing evidence base and logistic challenges in their healthcare system
Global Warming and Epidemic Trends of an Emerging Viral Disease in Western-Europe: The Nephropathia Epidemica Case
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