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Summary Pine wilt disease (PWD), caused by the pine wood nematode, Bursaphelenchus xylophilus, is an international quarantine forest disease that damages pine forests over extensive areas and causes massive economic losses. To provide valuable guidelines on screening pesticides against B. xylophilus and the selection of common solvents, we investigated the effects of different concentrations of emamectin benzoate, matrine and four solvents (methanol, ethanol, acetone and dimethyl sulfoxide) on the mortality and locomotor behaviour of B. xylophilus. Emamectin abamectin has nematicidal activity and mitigates locomotor activity of B. xylophilus at a low concentration. The LC50 of emamectin benzoate was 0.0354 mg l−1 at 72 h. Bursaphelenchus xylophilus mortality following exposure to matrine was low; however, nematode locomotor activity decreased by 62.5% following exposure to 500 mg l−1 matrine for 8 h. Additionally, B. xylophilus locomotor activity decreased significantly following exposure to 5 and 10% methanol, ethanol, acetone and dimethyl sulfoxide (DMSO) when compared with that of the water control. Emamectin benzoate and matrine, and high concentrations of four solvents (methanol, ethanol, acetone, and DMSO) inhibit B. xylophilus movement, which, in turn, could affect nematode infectivity. Moreover, low concentrations of non-lethal doses of emamectin benzoate should be considered for application in the control of nematodes, with matrine being an environmentally friendly and potentially nematicidal agent.

Mesenchymal stem cells (MSCs) secrete various cytokines with angiogenic and neuroprotective effects. This study aimed to assess the effects of human umbilical cord Wharton's jelly-derived MSCs (hWJ-MSCs) on diabetes-related intracavernosal pressure (ICP) impairment in rats. hWJ-MSCs were isolated from human umbilical cord Wharton's jelly and transplanted into the corpus cavernosum of streptozotocin (STZ)-induced diabetic rats by unilateral injection. The erectile function was evaluated at 4 weeks, as well as the expression levels of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), endothelial nitric oxide synthase (eNOS), and insulin-like growth factor 1 (IGF1). STZ-induced diabetic rats showed impaired ICP, which was significantly improved by hWJ-MSC treatment. VEGF, eNOS, IGF1, and bFGF expression levels were higher in hWJ-MSC injection sites than those in control ones in STZ-induced diabetic rats. These results suggest that hWJ-MSC transplantation might improve diabetic erectile dysfunction through increased production of paracrine growth factors, highlighting a novel potential therapeutic option for erectile dysfunction.

Cereal cyst nematode (Heterodera avenae) diapause is induced by high temperatures and is broken by low temperatures. In this study, metabolic responses were monitored in diapause and non-diapause H. avenae during exposure to 4°C for 10 weeks. The results showed that there was no difference in total carbohydrate content. The content of glycogen and glycerol at 0 week was relatively high but decreased with increased storage time at 4°C. The content of trehalose of the nematode at 10 weeks was significant lower than that at 5 weeks at 4°C. Protein content increased significantly after incubation for 5 and 10 weeks. Esterase and trehalase activity increased with the increasing period at 4°C and showed a significant difference between treatments for esterase activity but there was no significant difference between 5 and 10 weeks for trehalase activity. The SDS-PAGE pattern indicated that a 15.5 kDa protein was absent at 10 weeks and present at 0 and 5 weeks. Esterase isoenzyme patterns of H. avenae showed that at 10 weeks there were four bands: EST 0.21, EST 0.24, EST 0.30 and EST 0.34 (Rf values). EST 0.24 was the common band in the three treatments. Biochemical tests were conducted to correlate with hatching experiments using the same treatments. 2-DE patterns of H. avenae showed that diapause and non-diapause nematodes had 409 and 412 protein spots, respectively, and 19 protein spots were unique: 11 distinct proteins in non-diapause and eight distinct proteins in diapause. This information could be helpful in understanding the diapause mechanism of the cereal cyst nematode.

Stray light can directly influence the imaging quality and detection ability of space based detection system, and the stray light suppression of earth radiation is a key question needed to be considered by on-orbit detection system. First the basic principle and the mathematical model of stray light were analyzed here, then by using simulation analysis the requirements of stray light suppression under different imaging situations were obtained, this could be supportable for the design of space-based detection system.

To investigate the in-depth mechanism of turbulence control and drag reduction in a channel flow by using a spatially oscillating Lorentz force, the pseudo-spectral method based on standard Fourier–Chebyshev spectral method is used to solve N-S equations. The characteristics of controlled flow fields and vortex structures are described as well as the mechanism of the flow field control. The result shows that the near-wall flow structure is altered substantially and the turbulence drag decreases sharply under the action of the distributed Lorentz force with proper control parameters, the boundary-layer fluid are reciprocating periodic moving, and the vortex generation is impacted, and that only periodically well-organized streamwise vortexes are observed in the near-wall region of the turbulent channel flow.

Deep soil is a major organic carbon pool in terrestrial ecosystems. Labile carbon inputs can stimulate soil organic carbon (SOC) mineralization, causing priming effect, which in turn affects soil carbon emission. However, the mechanism of the priming effect in deep soil is still unclear. Therefore, to know how deep soil responds to labile carbon addition is essential for better understanding of deep soil carbon dynamics. In this study, we incubated three profiled soils (0-10 cm, 10-30 cm, 30-60 cm) from a subtropical forest with在陆地生态系统中,深层土壤是重要的有机碳库.外源碳输入可改变土壤有机碳(SOC)矿化速率(激发效应),进而影响土壤碳排放.然而深层土壤对外源碳输入的响应程度和方向如何还不清楚,引起激发效应的机理尚不明确.本文利用