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The surrounding rock of roadways in underground coal mines will lose its stability or even collapse under gas explosions, especially roadways surrounded by coals. The dynamic mechanical properties of coals were tested in order to investigate the dynamic response of coals under gas explosions. The static mechanical properties of coals were also tested as comparison. It is found that the dynamic stress-strain curves showed no obvious pore compaction stage comparing with uniaxial loading. The dynamic compression strength and the elastic modulus are obviously larger than those obtained in the static mechanical properties test, and the dynamic strain shows an obvious hysteresis phenomenon. The ultimate strain and absorbed energy increased linearly with increase of the strain rate. With the increase of dynamic loading, the fragment size of coal cores decreased obviously. The results could provide a reference for the antiexplosion design of the coal roadway.

The yield and quality of the medicinal plant Achyranthes bidentata can be increased when it is replanted into a field cultivated previously with the same crop, however, fundamental aspects of its biology (so-called “replanting benefit”) still remain to be elucidated. miRNAs are sRNA molecules involved in the post-transcriptional regulation of gene expression in plant biological processes. Here, 267 conserved and 36 novel miRNAs were identified in A. bidentata roots. We compared the miRNA content of the roots (R1) from first-year planting with that of the roots (R2) of second-year replanting, and screened 21 differentially expressed (DE) miRNAs. Based on in silico functional analysis, integrated miRNA-mRNA datasets allowed the identification of 10 miRNA-target family modules, which might participate in the benefit. The expression profiles of the miRNA-target modules were potentially correlated with the presence of the replanting benefit. The indication was that the miRNA-responsive continuous monoculture could reprogram miRNA-mRNA expression patterns, which possibly promote the root growth and development, enhance its transport activity and strengthen its tolerance to various stresses, thereby improving A. bidentata productivity as observed in the replanting benefit. Our study provides basic data for further research on the molecular mechanisms of the benefit in A. bidentata.

A straightforward synthesis of isoindolinones has been developed via a [3 + 3] benzannulation of 4-arylmethylene-2,3-dioxopyrrolidines and 1,3-bissulfonylpropenes (or 4-sulfonylcrotonates). A series of functionalized isoindolinones were obtained in excellent yields. The reaction could be carried out under mild conditions without transition metal catalyst. The finding provides a practical approach for the preparation of isoindolinone derivatives with potential biological activities.

A series of chiral polysulfonate cyclohexyldiamine-Ni(II) catalysts were prepared via sulfur (VI) fluoride exchange click-reactions. The catalysts exhibited good catalytic activity and enantioselectivity in the Michael addition of malonates to nitroalkenes. The excellent recyclability of the catalysts was demonstrated via the reuse of the privileged catalyst 7a for ten times. The results provide a new strategy for the immobilization of chiral homogeneous catalysts.

Selenium (Se), a nutritionally essential trace element, is associated with health and disease. Selenoprotein T (SelT) was identified as a redoxin protein with a selenocystein, localizing in the endoplasmic reticulum. The myosin light chain kinase (MLCK) and myosin light chain (MLC) play key roles in the contraction process of smooth muscle. The present study was to detect the effect and mechanism of SelT on the contraction process of gastric smooth muscle. The WT rats were fed with different Se concentration diets, and Se and Ca(2+) concentrations were detected in the gastric smooth muscle. Western blot and qPCR were performed to determine SelT, CaM, MLCK, and MLC expressions. MLCK activity was measured by identifying the rates of [γ-32P]ATP incorporated into the MLC. The results showed Se and Ca(2+) concentrations were enhanced with Se intake in gastric smooth muscle tissues. With increasing Se, SelT, CaM, MLCK and MLC expressions increased, and MLCK and MLC activation improved in gastric smooth muscle tissue. The SelT RNA interference experiments showed that Ca(2+) release, MLCK activation, and MLC phosphorylation were regulated by SelT. Se affected the gastric smooth muscle constriction by regulating Ca(2+) release, MLCK activation, and MLC phosphorylation through SelT. Se plays a major role in regulating the contraction processes of gastric smooth muscle with the SelT.

Selenium (Se) is an essential micronutrient affecting various aspects of health. The balance of the Se concentration has an important protective and promoter effect on physiological function in inducing muscular disorders in smooth muscle. Selenoprotein N (SelN) is closely related to Ca2+ release. The present study aimed to determine the effects and mechanism of action of dietary Se on uterine smooth muscle contraction via SelN using a mouse model. Quantitative polymerase chain reaction (qPCR) analysis was performed to detect mRNA levels. Western blotting was performed to detect protein levels. The results of the immunohistochemical analysis showed that Se had an effect on the uterine smooth muscle. The Se-supplement increased the release of Ca2+, Ca2+-calmodulin (CaM) expression, myosin light chain kinase (MLCK) expression, and myosin light chain (MLC) phosphorylation but did not affect ROCK and RhoA in uterine smooth muscle. Furthermore, the lack of Se showed an opposite impact. The effects of Se regulation were closely related to SelN. The interference of mouse SelN was performed on the uterine smooth muscle cell. Additionally, the results displayed the regulation of Se on the release of Ca2+, CaM expression, MLCK expression, and MLC phosphorylation were significant inhibited, and there was no effect on ROCK and RhoA. In conclusion, Se played an important role in regulating the process of contraction in uterine smooth muscle with SelN.

Evaluation of recent land degradation affecting Basra Province, Iraq, resulted in the identification of five prominent environmental degradation processes: desertification, secondary salinization, urbanization, vegetation degradation, and loss of wetlands. This analysis was carried out using ‘3S’ technologies [remote sensing, geographic information system (GIS), and global position system], with the layers extracted and manipulated from available topographic, climatic, and soil maps, as well as satellite image (thematic mapping in 1990 and enhanced thematic mapping in 2003) and field survey data analyses. Rates of conversion were calculated and distribution patterns were mapped with the aid of a GIS. The results revealed that land use changes have affected the wider environment and accelerated land degradation, with severe damage located in southwestern Basra Province representing 28.1 % of the total area. Areas of high to moderate degradation characterize the rest of the south, representing 52.7 % of the total area; while the north of the study region is characterized by very low and low degradation levels accounting for 8.5 and 10.7 %, respectively. Iraq faces serious environmental degradation problems that must be addressed immediately; failure to do so will greatly compound the cost and complexity of later remedial efforts, with environmental degradation beginning even now to pose a major threat to human well-being, especially among the poor.

This study presents an integrated study of expansion process of salinized land in Basrah Province, a typical salt-affected area in southern parts of Iraq, by using geo-information techniques. Satellite images (Landsat TM 1990) and thematic maps (ETM 2003) were used to provide comprehensive views of surface conditions such as vegetation cover and salinization detection. With ERDAS software, the normalized differential salinity index (NDSI) and salinity index (SI) were computed and then evaluated for soil degradation by salinization. ARC/INFO software was used along with field observation data (global positioning system) for analysis. During the past 13 years, the salinized land in study area increased by 6 579.1 km2 and in 2003 covered 34.5% of the total area; in the meantime, vegetation cover has decreased by 4 595.9 km2 and in 2003 covers only 24.1% of the study area. Environmental changes show that, between 1990 and 2003, 37.5% of vegetation cover and 45.9% of marshlands were transformed into salty meadow and wet salty crust, respectively. In addition, there was 16.6% of sand lands converted into dry puffy salty crust. Results using spatial analysis methods showed that 7 894.9 km2 (41.4%) of land had no risk of environment degradation by soil salinity, 4 595.9 km2 (24.1%) had slight risk, 4 042.8 km2 (21.2%) had moderate risk, and 2 536.3 km2 (13.3%) of the total land area was at a high risk of environment degradation by soil salinity. In conclusion, the study area was exposed to a high risk of soil salinity.

As we know, the garment varied between exaggeration and nature shape, as the supporting part of the tops, which also changed from emphasis to nature. Opening out qualitative and quantitative study on exaggerative shoulder shape was the hot point in the research field of garment construction, which had strong realistic significance. So depending on the warped shoulder shape, this paper selected the warped amount, which was the important effecting factors to the upturned shoulder shape, as research object. Through making up series of sample garments and subjective evaluation system, this article analyzed the effecting of the varying upturned amount to the warped shoulder shape, and got the best data of the upturned amount, which could offer some theoretical supporting to optimize the upturned shoulder shape

Air-jet pump as the pneumatic source of a vehicle-mounted vacuum toilet provides the vacuum to pump the fecal sewage out of toilet bowl via the compressed air passing through the pump under certain pressure. In this study, Computational Fluid Dynamics (CFD) technique is employed to investigate the effects of three important air-jet pump geometry parameters: the primary Nozzle Exit Position (NXP), the constant-area section length (L1) and the diffuser diverging angle (θ), on its performance. A CFD model is firstly established according to 1D analytical method, and then used to create 135 different air-jet pump geometries and tested under different operating conditions. The significance of this study is that these findings can be used to guide the adjustment of NXP, L1 and θ to obtain the best air-jet pump performance when the operating conditions are different.

Objective The human socio-economic development depends on the planet's natural capital. Humans have had a considerable impact on the earth, such as resources depression and environment deterioration. The objective of this study was to assess the impact of socio-economic development on the ecological environment of Wuhan, Hubei Province, China, during the general planning period 2006-2020. Methods Support vector machine (SVM) model was constructed to simulate the process of eco-economic system of Wuhan. Socio-economic factors of urban total ecological footprint (TEF) were selected by partial least squares (PLS) and leave-one-out cross validation (LOOCV). Historical data of socio-economic factors as inputs, and corresponding historical data of TEF as target outputs, were presented to identify and validate the SVM model. When predicted input data after 2005 were presented to trained model as generalization sets, TEFs of 2005, 2006, …, till 2020 were simulated as output in succession. Results Up to 2020, the district would have suffered an accumulative TEF of 28.374 million gha, which was over 1.5 times that of 2004 and nearly 3 times that of 1988. The per capita EF would be up to 3.019 gha in 2020. Conclusions The simulation indicated that although the increase rate of GDP would be restricted in a lower level during the general planning period, urban ecological environment burden could not respond to the socio-economic circumstances promptly. SVM provides tools for dynamic assessment of regional eco-environment. However, there still exist limitations and disadvantages in the model. We believe that the next logical step in deriving better dynamic models of ecosystem is to integrate SVM and other algorithms or technologies.

This study analyzes land use changes due to human development in the Mkomazi Valley, Tanzania, and its impacts on nature using the SD–Modeling (System Dynamic modeling) technique. Ultimately this method relates environment and economy of society with regard to a seasonal rainfall–based agriculture practice and their harmonization with irrigation agriculture for development sustainability. VENSIM PLE (VENTANA SIMULATION ENVIRONMENT, PERSONAL LEARNING EDITION 2002) software, which simplified the assessment, was used to build a SD–model that accommodated changes in Population, Deforestation, Gross Domestic Product (GDP), and Basin Storage. Model results indicate groundwater behavior, deforestation, public opinion and decreased health of the farmers all relate to changes in land use (i.e., introduction of a rice development project) with its associated environment degradation, deforestation, and poverty due to deforestation. Moreover, these changes might be the cause of animal flight from the Mkomazi...

A compatible relationship between “man” and “land” is the essence of regional sustainable development. In this article VENSIM PLE is used to set up a system dynamics (SD) model of the regional man–land system of Xiangfan, Hubei Province, China. The model is used to simulate dynamic behaviors of society and economy in the face of environmental catastrophe, in order to explore dynamic response among subsystems in man–land systems, and to research mechanisms of regional sustainable development. The model is also used to forecast impacts from the south-to-north water transfer project in China on the environment, society, and economy within a time span of 50 years. The model is further used to verify the effects of suggested regulatory policies. The simulation results show counterintuitive outcomes. The most serious impact on Xiangfan caused by the water transfer project would be on economic growth, not on environment quality. However, if a series of regulatory policies were carried out in advance of ...

Rapid urbanization has posed a considerable impact on the earth such as environment deterioration and resources degradation. Effectively predicting and evaluating the development trend of urban coordinated degree are key issues for urban sustainable development. In the paper, Important impact factors of coordinated development degree are obtained from grey relational analysis (GRA), and a Radial Basis Function Neural Network (RBFNN) model was built to simulate the trends of coordinated development of Wuhan city during 2006~2015. Results showed that three indexes, such as comprehensive utilization ratio of solid waste, unit GDP energy consumption and Gini coefficients, are the most important impact factors; Wuhan urban development would show a good coordination situation during studied period, but the coordinated development degree values predicted for 2010 (0.6824) and 2015 (0.7653) indicated that the city should be in the situation of primary coordination (2010) and intermediate coordination (2015). In the end, a series of countermeasures to improve the situation of development were further proposed.

The main methods to collect feces of livestock and poultry were briefly described. A new method using vacuum pipeline networks to collect feces of livestock and poultry was introduced. An example was also provided to amplify its technical scheme. The main methods of treatment and resource recovery of feces of livestock and poultry were reviewed. A new process of resource recovery of feces of livestock and poultry by using vacuum pipeline networks collection system, fast composting technology and micro-power underground sewage treatment system were introduced.

Vacuum Separate Collection and Transportation System of excreta, perishable domestic waste and domestic wastewater (VSCATS) is very useful in saving water, protecting the environment as well in utilize water more efficiently. Using this system, only 1 liter of water is needed in flushing the bedpan each time, so that freshwater can be saved. After bio-chemical treatment, the domestic waster reclaimed can be reused and the excreta and the perishable domestic waste can be used as organic fertilizer, so that a waste recycle and reuse ecological system is formed. This paper gives a brief introduction to the technological processes, working principles, the relevant technologies and the designing parameters.

Ecosystem health is the prerequisite for ecosystem service function. Assessment reflecting the trends of urban ecosystem health can improve 'information for decision making' on sustainability. Because urban areas are an advanced man-made complex ecosystem consisted of nature, society and economy, the key of urban ecosystem health assessment is to set suitable model for resolving the uncertainty of urban ecosystem. The paper establishes an assessment model of urban ecosystem health based set pair analysis (SPA) theory. The model can quantitatively calculate the health level of urban ecosystem through n-member connection number, so it can effectively deal with uncertain problems in urban ecosystem assessment. As an example, the urban ecosystem health states of Wuhan are thereafter evaluated using the model. The results show that: (1) the urban ecosystem health states of Wuhan are improving slowly; (2) among five assessing criteria, structure of Wuhan ecosystem is relatively reasonable, vigor and resilience can be regarded as the major disadvantages of the ecosystem; and (3) the model is suitable for urban ecosystem health assessment.

Ecosystem health is the prerequisite for ecosystem service function. To assure socio-economic sustainable development, how to effectively evaluate the trends of urban ecosystem health is a key issue for ecological planning. The paper established an evaluation model of urban ecosystem health based on the approaches of entropy weight and fuzzy logic mathematics, which avoided the uncertainty in estimating the standard of urban ecosystem health subjectively. Wuhan urban ecosystem was selected as an example for application and its health conditions from 1993 to 2004 was assessed. The results showed that: (1) The relative health status of Wuhan urban ecosystem health increased from 1993 to 2004. The most healthy year was 2003, and the least healthy year was 1994. (2) Based on the maximum membership degree principle, the maximum membership degree in human health group was 0.7627 (2003), in ecosystem service function group was 1.000 (2004), in social group was 1.000 (2001), in economic group was 0.9561 (2004), in environmental group was 0.7526 (1998).

To recognize and assess the impact of the South-to-north Water Transfer Project (SNWTP) on the ecological environment of Xiangfan, Hubei Province, situated in the water-out area, and develop sound scientific countermeasures.A three-layer BP network was built to simulate topology and process of the eco-economy system of Xiangfan. Historical data of ecological environmental factors and socio-economic factors as inputs, and corresponding historical data of ecosystem service value (ESV) and GDP as target outputs, were presented to train and test the network. When predicted input data after 2001 were presented to trained network as generalization sets, ESVs and GDPs of 2002, 2003, 2004... till 2050 were simulated as output in succession.Up to 2050, the area would have suffered an accumulative total ESV loss of RMB104.9 billion, which accounted for 37.36% of the present ESV. The coinstantaneous GDP would change asynchronously with ESV, it would go through an up-to-down process and finally lose RMB89.3 billion, which accounted for 18.71% of 2001.The simulation indicates that ESV loss means damage to the capability of socio-economic sustainable development, and suggests that artificial neural networks (ANNs) provide a feasible and effective method and have an important potential in ESV modeling.