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Purpose: Biochar is a promising soil amendment to improve soil quality. This study was conducted to understand the effect of biochar on soil physical and hydraulic properties and rice yield in a 3-year field experiment in Hunan Province of southern China. Materials and methods: We carried out a field experiment at the red paddy soils for 3 years to study the impact of biochar with different adding rates (at 0, 10, 20, 30, and 40 t/ha) on soil physical and hydraulic properties and rice yield. The clay content, soil bulk density, soil pH, soil organic matter, soil total nitrogen, soil total phosphorus, soil aggregates, the field capacity, the wilting point, the soil available water, and the rice yield were determined to explore long-term improved effects of biochar on soil properties and rice yield. Results and discussion: The results indicated that soil bulk density decreased significantly, but total porosity increased with biochar amendment. Biochar addition also caused macro-aggregates (> 2 mm) to increase and micro-aggregates (< 0.25 mm) decrease significantly, hence improving mean weight diameter of soil aggregates. Biochar addition had positive impact on soil field capacity and soil available water but no effect on soil wilting point. Soil saturated hydraulic conductivity was increased after biochar addition. Consequently, rice yield was increased due to the improvement of soil physical and hydraulic properties. Conclusions: The results showed there were significant differences in soil properties between biochar treatments and the control treatments over the 3-year field experiment, suggesting biochar addition had long-term effect on soil physical and hydraulic properties, as well as increasing rice yield. [ABSTRACT FROM AUTHOR]

Motivated by the discovery of λ(9.4), we study the semileptonic decay correlations of the next heavy quark, and their consequences for the e e colliding beam and neutrino experiments. A detailed comparison is made with the corresponding correlations from the production and decay of charm and heavy leptons, τ. Some tests of the $${\rm B}^0 - \bar {\rm B}^0 $$ mixing ( $$B = b\bar q$$ with baQ=−1/3 heavy quark) are suggested for e e colliding beam experiments. [ABSTRACT FROM AUTHOR]

Gloves are indispensable in many occupations. Irritant skin reactions twin gloves have. however, been reported. In the present study, the effect of long-term glove occlusion on normal skin ( 6 h/ day for 14 days) was studied and, in addition, the effect of a cotton glove worn under the occlusive glove was also studied, 2 studies were performed (studies A and B) Study A: 19 Volunteers wore and occlusive glove on normal skin 6 h/day fro 14 days. They wore the glove on one hand only, while the other hand served as control, Study B: 18 volunteers wore occlusive glove on both hands on normal skin. A cotton glove was worn under the occlusive glove on either the left or the right hand. Skin barrier function was evaluated by measurement of transepidermal water loss skin hydration by electrical capacitance (Corneometer) and inflammation by erythema index (Derma-Spectrometer) The gloves used were hypoallergenic non-later gloves, Results Study A: glove occlusion on normal skin 6 h/day for 14 days had a significant negative effect on skin barrier function, as measured by TEWL. Study B: the negative effect on skin barrier function from occlusive gloves was prevented by the use of a cotton glove. Its is concluded that gloves may be a substantial factor in the pathogenesis of cumulative irritant contact dermatitis, and that recommendations as to their use are important. [ABSTRACT FROM AUTHOR]