Maintenance of stemness is tightly linked to cell cycle regulation through protein phosphorylation by cyclin-dependent kinases (CDKs). However, how this process is reversed during differentiation is unknown. We report here that exit from stemness and differentiation of pluripotent cells along the neural lineage are controlled by CDC14, a CDK-counteracting phosphatase whose function in mammals remains obscure.
View Article and Find Full Text PDFLeachate generation from open stockpiles of recycled woodchip materials is potentially harmful to aquatic ecosystems. There is growing interest in using numerical models to simulate leachate generation from outdoor piles, but this requires information about the hydraulic properties of the materials. The objectives of this study were to simulate leachate from woodchip piles with the numerical model HYDRUS-3D and to optimize subsets of parameters for single (SPM) and dual (DPM) pore flow models with the Bayesian Markov Chain Monte Carlo algorithm DREAM.
View Article and Find Full Text PDFSoil macroporosity affects field-scale water-cycle processes, such as infiltration, nutrient transport and runoff, that are important for the development of successful global strategies that address challenges of food security, water scarcity, human health and loss of biodiversity. Macropores-large pores that freely drain water under the influence of gravity-often represent less than 1 per cent of the soil volume, but can contribute more than 70 per cent of the total soil water infiltration, which greatly magnifies their influence on the regional and global water cycle. Although climate influences the development of macropores through soil-forming processes, the extent and rate of such development and its effect on the water cycle are currently unknown.
View Article and Find Full Text PDFVariations in soil properties with depth strongly influence the degradation and persistence of herbicides, underlining the importance of studying these processes in soil horizons with distinctively different properties. The persistence of the herbicides acetochlor, atrazine, and S-metolachlor was measured in samples of the A, B, and C horizons of 2 Typic Argiudolls from Argentina under no-till management. The soils studied differed in soil organic carbon (OC) content, pH, particle size distribution, and structure.
View Article and Find Full Text PDFSoil pore structure has a strong influence on water retention, and is itself influenced by plant and microbial dynamics such as root proliferation and microbial exudation. Although increased nitrogen (N) availability and elevated atmospheric CO concentrations (eCO ) often have interacting effects on root and microbial dynamics, it is unclear whether these biotic effects can translate into altered soil pore structure and water retention. This study was based on a long-term experiment (7 yr at the time of sampling) in which a C pasture grass (Paspalum notatum) was grown on a sandy loam soil while provided factorial additions of N and CO .
View Article and Find Full Text PDFLarge-scale open storage of wood mulch is common practice at wood recycling facilities. During rain and snow melt, leachate with soluble compounds and suspended particles is released from mulch stockpiles. The objective of this study was to determine the quality of leachate/runoff from wood recycling facilities to evaluate its potential to contaminate receiving waterbodies.
View Article and Find Full Text PDFUnderstanding herbicide sorption within soil profiles is the first step to predicting their behavior and leaching potential. Laboratory studies were conducted to determine the influence of surface and subsurface soil properties on acetochlor, atrazine, and S-metolachlor sorption. Soil samples were taken from horizons A, B, and C of two loamy soils of the humid pampas of Argentina under no-till management; horizon A was divided into two layers, A(0) (0-5 cm) and A(1) (5 cm to the full thickness of an A horizon).
View Article and Find Full Text PDFIntroduction: In the postmenopausal period, an average of 25% of women will present symptomatic ovarian failure requiring hormonal replacement therapy. Estrogen can relieve vasomotor symptoms. Hormonal replacement therapy is generally not recommended for breast cancer patients due to the potential risk of tumor recurrence.
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