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Soil erosion is a major ecological problem in Danjiangkou reservoir area. Therefore, understanding the soil erosion mechanism of Danjiangkou reservoir area and conserving the water environment of the reservoir area is critical. Based on the revised universal soil loss equation(RUSLE) and the terrain characteristics of mountainous and broken terrain in Danjiangkou City, five factors, including rainfall erosivity, soil erodibility, topographic relief, vegetation coverage, and gully density were selected to develop a soil erosion sensitivity evaluation system. With the help of ArcGIS 10.2 platform, the soil erosion sensitivity of Danjiangkou City from 2012 to 2017 was comprehensively evaluated and the spatial distribution characteristics of soil erosion sensitivity in the study area under different underlying surface elements were analyzed. The results showed that the soil erosion sensitivity of Danjiangkou City was generally high in the northern and southern regions and low in the central region. Soil erosion sensitivity was characterized majorly as marginal and moderate sensitivity. Highly sensitive and extremely sensitive areas accounted for 13.53% of the total study area; during the five years, the moderately sensitive, marginally sensitive, and insensitive areas in Danjiangkou City showed an increasing trend, while the highly sensitive and extremely sensitive areas showed a downward trend; sparse woodland and unused land were highly sensitive land use types in the study area. The potential risk index of soil erosion in the study area increased initially and decreased later with the increase in slope. The research findings can serve as a reference for studying the soil erosion mechanism and developing strategies for the conservation of soil, water, and the overall ecosystem in Danjiangkou City.

The potential of 32 frequently studied ornamental and/or energy grasses and two cadmium/zinc hyperaccumulators for phytoextraction and phytostabilization was compared by their growth in a historically contaminated soil over a three-month pot experiment. Shoot and root biomasses varied by factors of 14.2 and 62.7, respectively. Mainly due to their large biomass, Napier grass (Pennisetum purpureum ‘Purple’) and variegated giant reed (Arundo donax var. versicolor) accumulated cadmium and zinc contents in shoots up to 109.3% and 55.4% higher, respectively, than those in the cadmium/zinc hyperaccumulators, despite their lower metal concentrations. Pennisetum purpureum ‘Purple’ accumulated the most zinc and the third highest cadmium in roots. Bioconcentration factors of cadmium in roots were greater than 1 for 19 grasses. The present study demonstrated that many of these grasses may be suitable for phytostabilization of soil cadmium. Arundo donax var. versicolor exhibited the most potential for phytoextraction of soil zinc, whereas Pennisetum purpureum ‘Purple’ was best for phytoextraction and phytostabilization of cadmium and phytostabilization of zinc. Ornamental/energy grasses may have greater potentials for soil remediation than hyperaccumulators, especially given their utility and eco-economic benefits. The considerable variation in their performance emphases the value of screening to select the most effective candidates.

Airway remodeling represents the healing and alteration in the airway that occur as a consequence of chronic inflammation. Extracellular matrix synthesis regulated by transforming growth factor (TGF-β1) and vascular remodeling regulated by epidermal growth factor (EGF) are important factors for the airway remodeling. This study aimed to probe the effect of catalpol, a major component of Radix Rehmanniae Preparata (Shudihuang), on airway remodeling and expression of TGF-β1 and EGF in asthmatic mice. A mice model of asthma was induced by ovalbumin (OVA) treatment. BALB/c mice were randomly divided into blank control group, asthma model group, dexamethasone (DEX) group (positive control), high, medium and low dose of catalpol intervention group. Changes in lung histology were observed using hematoxylin and eosin staining. The levels of TGF-β1 and EGF in mouse sera and bronchoalveolar lavage fluid (BALF) were examined by ELISA. The EGF mRNA and protein levels in mice tissues were determined. The results indicated that catalpol improved general conditions and reduced the damage of lung tissues in asthmatic mice. Moreover, results of ELISA revealed that catalpol significantly reduced the OVA-induced levels of TGF-β1 and EGF in sera and in bronchoalveolar lavage fluid (BALF). Additionally, results indicated that catalpol decreased the OVA-induced EGF mRNA and protein expression in lung tissues in asthmatic mice. Catalpol at a high dose was more efficient in decreasing the level of TGF-β1 in mice sera and BALF comparing the DEX group. Current study has demonstrated that catalpol might effectively prevent airway remodeling in asthma via inhibiting TGF-β1 and EGF.

Myasthenia gravis (MG) is an autoimmune neuromuscular junction disorder which is characterized by fluctuating muscle fatigue. However, the association of MG with nemaline myopathy is rarely reported. Here we report a case of MG coexisting with adult-onset nemaline myopathy. A 55-year-old man endured fluctuating muscle weakness with positive acetylcholine receptor and titin antibodies. After the patient was administrated cholinergic drugs and immunosuppression, the muscle weakness of the patient had mildly been alleviated. Electromyography showed a progressive decrement in the amplitude of muscle action potential at low frequency. Muscle biopsy showed numerous nemalines in the muscle fibers. This is the first reported case of nemalines present in the muscle fibers of adult patient with MG. The pathogenesis of nemaline may be related to titin antibody in adult-onset nemaline myopathy with MG.

Using multi temporal satellite images of remote sensing,wetland information was extracted by decision tree classification method combined with field surveying and four Lake Dongting's wetland type distribution maps were drawn out.This paper mainly analyzes the dynamic characteristics of wetland vegetation,driving factors and their influence on the wetland ecosystem in this region.Results show that vegetation community distribution and proportion changed obviously.In the past 17 a,forest area increased by 367.88 km2 at a rate of 1127.51%.The forest area extended to main part of beaches and became the main vegetation type of Lake Dongting.Reed area decreased by 44.09 km2,while sedge land area increased by 2.99 km2,with change rate of-5.80% and 0.40%,respectively.This change resulted from both natural environment evolution and human activities.The destruction of natural wetland vegetation,especially planted reed and poplar,destroyed the structure and function of Lake Dongting wetland ecosystem.In order to protect the Lake Dongting wetland effectively,we must rationally exploit bottomland resource,protect natural wetland vegetation and make good management on shoal forestation.

Finite-element analysis method is used to make numerical analysis of fins with an excessive width and the unfavorable consequences are directly displayed in this paper. Compensation measures are proposed to increase the fin thickness or the thickness of fin root. Besides, the results of numerical analysis and compensation effect of the measures are provided for further discussion.