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Vegetation plays an important role in soil erosion control, but few studies have been performed to quantify the effects of vegetation stems on hydraulics of overland flow. Laboratory flume experiments were conducted to investigate the potential effects of vegetation stems on Reynolds number, Froude number, flow velocity and hydraulic resistance of silt-laden overland flow. Cylinders with diameter D of 2·0, 3·2 and 4·0 × 10−2 m were glued onto the flume bed to simulate the vegetation stems, and a bare slope was used as control. The flow discharge varied from 0·5 to 1·5 × 10−3 m3 s−1 and slope gradient was 9°. Results showed that Reynolds number on vegetated slope was significantly higher than that on bare slope because of the effect of vegetation stems on effective flow width. All the flows were supercritical flow, but Froude number decreased as D increased, implying a decrease in runoff ability to carry sediment. The mean flow velocity also decreased with D, while the velocity profile became steeper, and no significant differences were found in surface flow velocities among longitudinal sections on all slopes. Darcy-Weisbach friction coefficient increased with D, implying that the energy consumption of overland flow on hydraulic resistance increased. Reynolds number was not a unique predictor of hydraulic roughness on vegetated slopes. The total resistance on vegetated slopes was partitioned into grain resistance and vegetation resistance, and vegetation resistance accounted for almost 80% of the total resistance and was the dominant roughness element. Further studies are needed to extend and apply the insights obtained under controlled conditions to actual overland flow conditions. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Highlights: [•] A class of simple chiral diamines (4) were designed and synthesized. [•] The copper(II) complexes were efficient catalysts in the asymmetric Henry reaction. [•] Our results show that 4g-Cu(OAc)2 could be readily recovered and reused. [•] The procedure could be used to obtain large amount of β-nitroalcohol. [•] A possible catalytic transition state was suggested for the asymmetric Henry reaction. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of nanosized cadmium sulfide (nano-CdS) on the male reproductive system in mice., Methods: Thirty-six specific pathogen?free male ICR mice were equally and randomly divided into three groups: two experimental groups and a control group. The two experimental groups were exposed to 100 mg/kg and 50 mg/kg nano-CdS once daily by gavage, respectively, while the control group was exposed to the same volume of physiological saline once daily by gavage. After 45 days, levels of cadmium accumulation and serum testosterone in the testis were determined, the epididymal sperm count, the rate of sperm abnormality, and histopathological changes in testis tissue were observed under a microscope, and the level of CYP11A1 mRNA was determined by qRT-PCR., Results: Compared with the control group, the two experimental groups had a significantly increased level of cadmium accumulation in the testis (P < 0.05), and the 100 mg/kg nano-CdS group had a significantly decreased epididymal sperm count (P < 0.05) and a significantly increased rate of sperm abnormality (P < 0.05), but the 50 mg/kg nano-CdS group did not. The 100 mg/kg nano-CdS group showed different histopathological changes in testis tissue, but the 50 mg/kg nano-CdS group did not. The two experimental groups had significantly reduced levels of testosterone and CYP11A1 mRNA compared with the control group., Conclusion: Nano-CdS given through the digestive tract may have an effect on the male reproductive system in mice by affecting the key enzyme genes in the androgen synthesis pathway to reduce the levels of reproductive hormones.

Objective: To evaluate the impact of nasal obstruction on OSAHS., Method: One hundred and twenty cases of OSAHS with or without nasal obstruction were analyzed by Hypno PTT(PTT)and Mallampati score (MS); Acoustic rhinometry was measured in all 120 cases., Result: A significant correlation was found between the MS and the AHI measured during the sleep (r = 0.266, P < 0.01). The relative risk of OSAHS with a MS of III or IV in the whole group was 1.96, and 2.46 in cases with nasal obstruction., Conclusion: A high MS represents a predisposing factor for OSAHS, especially in which associated with nasal obstruction.

Objective: To obtain more information on the distribution of F-actin in the guinea pig cochlea, to observe the effects of conditioning noise exposure on the expression of F-actin and to study this "toughening" phenomenon mechanisms., Method: An octave band noise centered at 1 kHz at 95 dB SPL for 8 hours a day was used as conditioning noise. Animals were killed at different time points after different conditioning noise exposure. The organs of Corti were labelled by FITC-phalloidin and examined using laser scanning confocal microscopy following cochlear preparation., Result: High intensity labeling of F-actin was seen in both inner and outer hair cells, specifically in stereocilia, cuticular plates. In the circumferential rings around the apical periphery of each cell, the head plates of the pillar cells, the lowest portion of OHC bodies, which represented the Deiters cup and in the phalangeal processes of Deiters cell, the strong labelling of F-actin was also seen. F-actin was found in the out pillar cells' body. F-actin labelling of OHCs in differently conditioning exposed animals was different., Conclusion: (1) Conditioning exposure can change the expression of F-actin in guinea pig cochlea. (2) In the organ of Corti of guinea pig, F-actin distributes not only in the portions previously reported, but also in the out pillar cell' s body. (3) A reduced expression of F-actin in out hair cell after conditioning exposure may be connected to the "toughening" phenomenon.