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Since the reform and opening up, the socioeconomic status of women in rural China has risen rapidly. However, unlike men, women have not been able to earn higher wages by "working in all directions". Based on the interview data of 2064 migrant workers, this paper explores the nonlinear interaction of individual characteristics and urban geographic factors with gender differences in migrant workers' wages with the help of random forest regression models. The results show the following: (1) migrant workers' wages show obvious gender differences in different dimensions, but in general, men's wages are higher than women's wages; (2) there are also gender differences in the influencing factors of migrant workers' wages. Work experience is more important for male migrant workers' wages, age is more important for female migrant workers' wages, and there is a variable effect of each factor on migrant workers' wages. This paper is of great help in understanding the travel trajectories of migrant workers and gender differences in wages and holds reference value for guiding migrant workers in choosing jobs and places and increasing their income. [ABSTRACT FROM AUTHOR]

Coal is the primary source of energy in China's energy structure system. With the large-scale mining of mineral resources, a large amount of mine water will be produced in the process of development, construction, and production, which will pollute and damage the ecological environment of mine water. At present, China vigorously advocates coal revolution, implements low-carbon economy, and carries out clean production of energy development and utilization. Green mining, precision mining, and other strategic ideas have been applied to mine development to guide production practice. This paper does an in-depth analysis of the physical, chemical, biological, and environmental characteristics of mine water, puts forward the basic classification of mine water, and points out the characteristics of environmental hazards of mine water. Aiming at different types of mine water, such as mine wastewater, drainage water, goaf water, mine water with suspended solids, high salinity mine water, acid mine water, and mine water with special pollution, the paper puts forward the mine water treatment and resource utilization technology with different characteristics and strong pertinence. On this basis, the comprehensive treatment and development direction of mine water in the future are prospected. [ABSTRACT FROM AUTHOR]

[Display omitted] • The volcano-plutonic complex was mainly generated by the partial melting of lower crust. • Mantle delamination generated heterogeneous magma and thus a variety of deposits. • Intracontinental tectonic transformation controlled the porphyry emplacement. The Yao'an Pb–Ag–Au deposit is located far from the present-day margin of the Yangtze Craton, providing an excellent example for studying the genesis of porphyries and associated polymetallic mineralization in intracontinental transpression settings. In situ zircon U–Pb ages and Sr–Nd–Hf–O isotopic data of the Yao'an porphyries in the intracontinental zone, combined with research data published for the Machangqing and Beiya ore-bearing porphyries in the cratonic margin, were used in this paper. Four-phase felsic rocks (∼33 Ma) and later mafic rock (∼31 Ma) were recognized in the Yao'an district. Of these, the third-phase syenite porphyry had a genetic link with Pb–Ag–Au mineralization, which occurred within the second-phase volcanic rocks and Mesozoic strata. In addition, the Yao'an porphyry showed high initial 87Sr/86Sr ratios (0.7087–0.7094) and enriched Nd (ε Nd (t) = −10.53 to −12.60) isotopic composition, with a wide range of zircon Hf (ε Hf (t) = −8.39 to −13.2) and δ 18O values (6.28 ‰–9.20 ‰). These features suggest that the Yao'an porphyries were produced by partial melting of an ancient lower crust mixed with continental lithospheric-mantle-derived melt, which are differed from the magma source of the Beiya and Machangqing porphyries. Given the nature sources of the porphyries, we conclude that the spatial variation of metal associations changing from the Cu ± Au ± Mo system at the cratonic margin to the Pb–Ag–Au deposits in the intracontinental zone in the western Yangtze Craton was likely controlled by different magma sources. The delamination of an overthickened continental lithospheric mantle in an intracontinental transpression setting was a geodynamic trigger for porphyry magma generation, ascent, and emplacement. [ABSTRACT FROM AUTHOR]

Abundant organic inclusions are present in the Qinglong antimony deposit. However, the source rocks of these organic matters have not been reliably identified. Recently, a paleo-oil reservoir was found in the Qinglong antimony deposit. In view of similar components of gaseous hydrocarbon, we propose that the organic matters observed in inclusions in Qinglong antimony deposit would come from this paleo-oil reservoir. We used the Re-Os dating method to determine the age of the bitumen from this paleo-oil reservoir, and obtained an isochron age of 254.3±2.8 Ma. The age indicates that the oil-generation from source rock occurred in the early Late Permian, earlier than the Sb mineralization age (∼148±8.5 Ma) in the Qinglong antimony deposit area. After oil generation from Devonian source rock, first and secondary migration, the crude oil have probably entered into the fractures and pores of volcanic rocks and limestone and formed a paleo-oil reservoir in the western wing of Dachang anticline. As burial process deepened, the crude oil has turned into natural gas, migrates into the core of Dachang anticline and formed a paleo-gas reservoir. The hydrocarbons (including CH4) in the reservoirs can serve as reducing agent to provide the sulfur required for Sb mineralization through thermal chemical reduction of sulfates. Therefore, the formation of oil-gas in the area is a prerequisite for the Sb mineralization in the Qinglong antimony deposit. [ABSTRACT FROM AUTHOR]

Stocking of filter-feeding fish is a common tool used in Chinese reservoirs to increase fish production because of low natural recruitment. Whether such stocking has important negative effects on zooplankton with cascading effects on phytoplankton is debated. We compared the zooplankton communities in fourteen reservoirs with different nutrient concentrations and fish densities. Both chlorophyll a (Chla) and fish catch were positively related with total phosphorus (TP), whereas zooplankton biomass did not show a similar relationship with TP. Zooplankton seemed to be influenced by fish as high fish catches coincided with a low proportion of calanoids of the total copepod biomass, a high proportion of rotifers of the total zooplankton biomass, a low zooplankton:phytoplankton biomass ratio, and the absence of Daphnia irrespective of TP concentration. Both zooplankton biomass and most of the zooplankton:phytoplankton biomass ratios were among the lowest reported in the literature for the nutrient range studied. Furthermore, the Chla:TP ratio was higher than what is typically observed in temperate lakes. We conclude that top-down control of zooplankton is of key importance in reservoirs in South China where frequent stocking of filter-feeding fish seems to contribute to poor water quality in the form of higher algal biomass and reduced clarity. [ABSTRACT FROM AUTHOR]

The sequence stratigraphy and geochronology of the terrestrial dinosaur-bearing strata, i.e., the Qiupa Formation, were poorly studied in the Luanchuan-Tantou Basin in western Henan, China. This study shows that these strata represent a complete succession from the Late Cretaceous to the early Paleogene, including the K/T boundary, in this area. Here we report a detailed study of the K/T boundary, especially its stratigraphic sequence, sedimentary characteristics, integrity, continuity, and geological implications. [ABSTRACT FROM AUTHOR]

• The four mutant loci in the ASB-3 gene were identified by Tetra-primer ARMS-PCR method. • Four mutant loci in the ASB-3 gene were found to be significantly associated with some body traits in Qinchuan cattle, Jinnan cattle and Xianan cattle. • Validation of ASB-3 as a candidate genetic marker for molecular breeding of China cattle. ASB-3 is one of the 18 members of ASB gene family. As a special negative regulation factor of TNF-R2, ASB-3 inhibits the signal transduction of JNK-TNF-R2 and JNK-STAT signaling pathway by TNF-R2 protein. In this study, the genetic polymorphisms of ASB-3 were detected in total of 637 from Qinchuan, Jinnan and Xianan cattle using the sequence of mixed DNA pool, Tetra-primer ARMS-PCR and PCR-RFLP methods. Four mutation sites were detected including the g.C41255T, g.G74754A, and g.T75438C were synonymous mutation, whereas the g.C115213T was missense mutation (Pro > Ser). The associated analysis of four polymorphic loci of ASB-3 gene respectively with growth traits in the three cattle breeds. The result showed that SNP1 site was significantly related with Qinchuan cattle height and TT was the dominant genotype; SNP2 had a significant relationship with body length of Xianan cattle and cross department height of Qinchuan cattle, AA was the dominant genotype; SNP3 was significantly related to cross height of Xianan cattle, TT was the dominant genotype; SNP4 site was significantly correlated with body height of Xianan cattle and cross height of Jinnan cattle. Genotype combinations were only significantly correlated with the hucklebone width in the adult Qinchuan cattle. The combination genotype CTAGCTCC was outperformed other combination genotypes of Qinchuan cattle. The results showed that ASB-3 could be an important candidate gene and the four SNPs in ASB-3 can be used for molecular marker-assisted selection of four beef cattle breeds. [ABSTRACT FROM AUTHOR]

Contents of copper and zinc in feed, manure, meat of livestock and poultry, and soil applied with manure in Liaoning, China were determined by atomic absorption spectrometry. The average contents of copper in chicken and pork were exceed the maximum limit values provides by Chinese standard GB15199-94. The application of pig and chicken manure has led to a certainty extend pollution of copper and zinc in soil, which becomes severity in the release of heavy metals in plantation., (Copyright © 2011 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.)