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In recent years, with the continuous improvement of China’s urbanization level, the transfer of agricultural population to cities has stepped up, and the number and scale of grain stored by farmers have shown a significant downward trend. However, the problem of grain postpartum loss caused by improper storage of farmers is still prominent every year. This paper mainly conducts in-depth investigation and analysis on the characteristics, loss rate and loss causes of the front-end storage links of farmers’ grain in China. The study found out that at present, the scale of grain storage of farmers in China is gradually decreasing, but the total scale is still large. The purpose of grain storage of farmers is mostly used for rations and feed grain, and a small amount is to wait for a better time to sell grain. There are regional differences in the number and scale of grain storage of farmers, which is mainly manifested in the fact that the main production area is higher than the production and marketing balance area and the main sales area. The study also found that the loss rate of grain storage in China’s farmers showed a downward trend, and there were significant differences in the loss rate of grain storage among farmers. Due to the poor storage facilities of farmers, improper storage management, weak scientific storage awareness, lack of storage technology and other reasons, the loss of rodents, mildew and pests is large, among which the loss of rodents is the most serious. Finally, the study also puts forward some countermeasures and suggestions for targeted derogation management.

Manipulating an exogenous or endogenous gene of interest at a defined level is critical for a wide variety of experiments. The Gal4/UAS system has been widely used to direct gene expression for studying complex genetic and biological problems in Drosophila melanogaster and other model organisms. Driven by a given tissue‐specific Gal4, expressing UAS‐transgene or UAS‐RNAi (RNA interference) could be used to up‐ or down‐regulate target gene expression, respectively. However, the efficiency of the Gal4/UAS system is roughly predefined by properties of transposon vector constructs and the insertion site in the transgenic stock. Here, we describe a simple way to modulate optomotor blind (omb) expression levels in its endogenous expression region of the wing disc. We co‐expressed UAS‐omb and UAS‐omb‐RNAi together under the control of dpp‐Gal4 driver which is expressed in the omb expression region of the wing pouch. The repression effect is more sensitive to temperature than that of overexpression. At low temperature, overexpression plays a dominant role but the efficiency is attenuated by UAS‐omb‐RNAi. In contrast, at high temperature RNAi predominates in gene expression regulation. By this strategy, we could manipulate omb expression levels at a moderate level. It allows us to manipulate omb expression levels in the same tissue between overexpression and repression at different stages by temperature control. [ABSTRACT FROM AUTHOR]

According to a narrow effective separation particle size of a coarse slime separator in the industrial liquid-solid fluidized bed and a low separation efficiency to difficulty washed coal,a theoretical study on the medium density affected to the separation effect of liquid-solid fluidized bed was conducted and upflow clean water flow in the liquid-solid fluidized bed was replaced with heavy medium flow.Under the two upflow conditions individually,the coarse slime separation experiments of the liquid-solid fluidized bed with different flow rate were conducted on the coarse slime with particle size of 3∼0.25 mm.The results showed when heavy medium flow was applied to the separation,the separator would effectively have an effective separated particle size scope of the coarse slime expand to 3∼0.25 mm and a deviation value possibly would be 0.05∼0.10 g/cm3. Under a high flow rate,the ash content of the clean coal could be reduced to 9.85%.When the ash contents of the clean coal was required not over 11%,the clean coal production rate would be improved by 10.21%. [ABSTRACT FROM AUTHOR]

Information on the spatial distribution of soil microbial communities on the Tibetan Pla-teau is critical for in-depth understanding the important roles of microbes in typical alpine ecosystems. In this study, 16S rDNA Illumina Miseq sequencing was used to analyze the variations in bacterial community composition and functional potentials in soils sampled from four elevations on Mount Segrila, Tibet, and the driving environmental factors. Results showed that richness and Shannon diversity index of soil bacteria significantly decreased with increasing altitude. The relative abundances of Acidobacteria, Chloroflexi, Gemmatimonadetes, and Nitrospirae significantly increased, whereas that of Proteobacteria, Actinobacteria and Bacteroidetes significantly decreased with increasing altitude. In KEGG pathway (level Ⅱ), the relative abundance of genes related to membrane transport and the metabolism of amino acids, lipids, terpenoids and polyketones was significantly lower at high elevations. In contrast, genes related to carbohydrates metabolism, signal transduction, replication and repair and enzyme family were more abundant at high altitudes. Soil bacterial community composition and predicted functions were significantly affected by vegetation types and soil properties, with soil pH being the key driver. There were significant correlations between the abundances of predicted functions and bacterial taxa, such as Acitnobacteria, Bacteroidetes, and Fibrobacteres. The dissimilarity in the composition of KEGG pathway genes along the elevational gradient (β-diversity) showed a significantly positive correlation with the dissimilarity in bacterial community structure, indicating that there was a strong relationship between microbial community composition and potential functionality.

The intensification and industrialization of agricultural production leads to more and more serious separation of crop and livestock, which causes serious contradiction between livestock excrement and environment, and major challenges for agricultural sustainable development. Here, we quantitatively investigated the spatial pattern and evolutionary trend of the sustainable development index (ESI) of the crop-livestock system using the emergy analysis and the input/output data in Shandong Province (1999-2015). The results showed that the sustainability of the crop-livestock system in Shandong Province decreased from 1999 to 2015 by 22.0%. The net emergy yield ratio (EYR), environmental load ratio (ELR), and the benefits of unit economic inputs significantly increased. The environmental pressure from the crop and livestock production increased obviously, which was closely related to the increase of industrial resources input including electricity, compound fertilizer, and agricultural machinery. There were differences in the sustainable development level of the crop-livestock system among administrative prefectures in Shandong Province. The ESI level of crop-livestock system in most regions was relatively high, while that in the coastal regions (e.g., Weihai, Yantai) and industrial region (e.g., Zibo) was relatively low. The trends of the sustainable development of crop-livestock system varied in different cities. The sustainability of central and southern Shandong was decreasing, while that of northern Shandong was increasing year by year. In 2015, the ESI of the expected crop-livestock system (100% livestock manure replaced fertilizer) could reach 8.4, which was 2.6 times of that of the current crop-livestock system (30% livestock manure replaced fertilizer).