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This study combined theoretical analysis, numerical simulation via FLAC3D software, innovative design, and field measurements for establishing the mechanical model of the stressed coal rock and deriving the deformation and failure characteristics of the roadway in a steep coal seam. The No. 49# steep-seam working face of the Xintie Coal Mine, China, was used as a case study with asymmetrical force characteristics of the mining roadway. The roof and the right side of the roadway under study were identified as the main deformation and failure zones in the roadway of the steep working face. Next, a rigid/flexible support method that fully enclosed two sides and the roof was designed and substantiated. It comprised three pre-stressed resin anchor cables combined with anchor rods, iron net, and steel bands for the roadway roof support; besides, three anchor rods were combined with iron net and steel bands for supporting the right side of the roadway. A novel self-mobile forepoling hydraulic support group with side and roof support functions was developed. A grouting reinforcement was applied to the crushed coal rock in the geologic anomaly zone to enhance the overall performance. Finally, the measured displacements of the roof and the floor were found to exceed those of the roadway sides. The whole advancing process of the steep-seam working face was conditionally split into three segments, namely, Segment I with no mining effect (at a distance over 50 m from the working face), Segment II with a mining effect (at 20 ~ 50 m from the working face), and Segment III with a strong mining effect (20 m in front of the working face). The displacement at the deepest point on the roof was the maximal, followed by that in the range of 0 ~ 1.5 m, which made it possible to reduce the number of anchors on the left side of the roadway required by the conventional symmetric support mode. The performed field measurements proved that the proposed asymmetric support mode ensured the mining safety requirements of the working face under normal mining operations, being more cost-effective and efficient than the conventional symmetric one. [ABSTRACT FROM AUTHOR]

The mechanisms underlying the retention of inorganicNin acidic forest soils in southern China are not well understood. Here, we simultaneously quantified the gross N transformation rates of various subtropical acidic forest soils located in southern China (southern soil) and those of temperate forest soils located in northern China (northern soil). We found that acidic southern soils had significantly higher gross rates ofN mineralization and significantly higher turnover rates but a much greater capacity for retaining inorganicN than northern soils. The rates of autotrophic nitrification and NH3 volatilization in acidic southern soils were significantly lower due to low soil pH. Meanwhile, the relatively higher rates of NO3 - immobilization into organic N in southern soils can counteract the effects of leaching, runoff, and denitrification. Taken together, these processes are responsible for the N enrichment of the humid subtropical forest soils in southern China. [ABSTRACT FROM AUTHOR]

The 18 biochemical parameters of serum were measured to analyze the pathogenic risks of the Yangtze River Source of Drinking Water in Nanjing area (YZR-SDW-NJ) on mouse Mus musculus for protection of human health in this research. The male mice Mus musculus were sampled and fed with YZR-SDW-NJ for 90 days then the eighteen serum biochemical levels were measured with Automatic Biochemical Analysis/RerLi 600. And the parameter data were treated by One-Way ANOVA statistic approach. The results showed that five parameter levels for the sample group mice were different from those for the control group significantly (0.01 < P or 0.05 < P). Four 4 of the 5 altered parameter levels were decreased including glutamate pyruvate transaminase 38% lower, glutamine-oxaloacetic transaminase 24% lower, triglyceride 76% lower and cystatin C 73% lower, only creatinine level was 26% higher than that in the control group. The data suggest that YZR-SDW-NJ had toxicity on the mouse and the organic pollutants in YZR-SDW-NJ might lead to liver, kidney, cardiovascular and metabolic pathogenic risks on the human beings. The results might be cited as evidence to control pollutants in the source water for the protection of NJ people's health. [ABSTRACT FROM AUTHOR]

Stripe rust, caused by Puccinia striiformis f. sp. tritici (PST), is one of the most important diseases of common wheat ( Triticum aestivum L.). China has the largest stripe rust epidemic areas in the world and yield losses can be large. Aegilops tauschii Coss, the D-genome progenitor of common wheat, includes two subspecies, tauschii and strangulata (Eig) Tzvel. The ssp. strangulata accession AS2388 is highly resistant to the prevailing physiological races of PST in China, and possesses a single dominant gene for stripe rust resistance. In order to tag this gene, AS2388 was crossed with the highly susceptible ssp. tauschii accession AS87. The parents, F plants, and F families were tested at adult plant stage in field trials with six currently prevailing races. Simple sequence repeat (SSR) primers were used to identify molecular markers linked to the resistance gene. SSR markers Xwmc285 and Xwmc617 were linked to the resistance gene on chromosome arm 4DS flanking it at 1.7 and 34.6 cM, respectively. Based on the chromosomal location, this gene temporarily designated as YrAS2388 is probably novel. The resistance in Ae. tauschii AS2388 was partially expressed in two newly developed synthetic hexaploid backgrounds. [ABSTRACT FROM AUTHOR]

The article discusses a study on a ribonucleic acid (RNA)-splicing mutation in TRAPPC2 gene identified in a large Chinese family with X-linked spondyloepiphyseal dysplasia tarda (SEDT). The proband of the family is a 38-year-old man who has been experiencing chronic pain at joints that bear weight. Family members were subjected to blood analysis in which genomic deoxyribonucleic acid (DNA) was extracted and total RNA was isolated. It concludes that clear quantitative genotype-phenotype correlation for the mutation of TRAPPC2 gene is yet to be determined.

On the basis of NCEP/NCAR version I daily reanalysis data from 1971 to 2000 and by the methods of inverse calculation, correlation analysis and comparative analysis, the influences of atmospheric heat source (AHS) over the Tibetan Plateau on the large-scale AHS and the general circulation in summer are studied in this paper. The results show that AHS over the plateau in summer may trigger a heat source wavetrain propagating northeastward along the coast from the East Asian continent and West Pacific to Bering Strait-Arctic or even North Amend. In addition, if AHS over the eastern plateau is intense, South Asian High moves to southeast and West Pacific subtropical high moves to southwest; on the contrary, if AHS over the eastern plateau is weak, South Asian High moves to northwest and West Pacific subtropical high moves to northeast. Therefore, South Asian High and West Pacific sub tropical high move in the horizontally-opposite directions in terms of interannual variation, for which AHS over the e stern plateau seems to be thermodynamically responsible. [ABSTRACT FROM AUTHOR]

Large scale heterogeneous distribution of biodiversity has become a hot topic for ecologists and conservationists. A threat status assessment combined with geographic distribution patterns of threatened plants in China has been conducted at a national scale in this study based upon a distribution database that refers to both specimen records and published references. Currently, 302 threatened plant species are cataloged in the "National Protected Key Wild Plants" in China belonging to 92 families and 194 genera. Results of the assessment according to the Categories and Criteria system of The World Conservation Union (IUCN) Red List indicate that three species have been assessed as Extinct in Wild (EW) while a further 79, 99 and 112 species have been assessed as Critically Endangered (CR), Endangered (EN), and Vulnerable (VU), respectively. Distribution patterns of threatened plants were analyzed with GIS to identify areas of high species diversity. It was found that threatened plant species occur unevenly within counties and are concentrated in the following eight hotspots: the central and southern Hengduanshan mountain area; the southeast regions of Yunnan as well as Xishuangbanna and southwestern Guangxi; the southern Hainan island; the border mountainous regions of Guizhou, Hunan and Guangxi provinces; the mountainous regions of southwestern Hubei and northern Hunan; southwestern Zhejiang and western Fujian; central Sichuan and southern Gansu; and the western mountains of Guangdong. Moreover, the 12 counties with the greatest number of threatened plant species represent cumulatively more than 50% of the total listed species and, therefore, are the regions in China that should be prioritized for conservation efforts. By overlapping the map of threatened plant species with the distribution of national nature reserves, a gap was identified in protected areas. This research will ultimately provide insights for prioritizing biodiversity conservation as well as processing the mechanisms of distribution patterns. [ABSTRACT FROM AUTHOR]

Endemic fluorosis was investigated and studied in the west region of the Songnen plain, Northeast China in 2001–2002. The results showed that the fluorine distribution in aquatic environment was that the fluorine concentrations in the lake water and unconfined ground water were higher than that in the river water and confined ground water. The lake water (Alkali lake) is connected with unconfined ground water. In unconfined ground water, from the east and southeast areas to the west and the northwest areas of the plain, fluorine concentration fluctuated with high and low alternatively. The fluorine in the water comes from the weathering of rocks and minerals in the mountains and hills around the Songnen Plain. The main influence factors of the fluorine distribution in aquatic environment are discussed. Unconfined ground water containing high fluorine is used as drinking water. In this region, the fluorine concentration in drinking water is evidently correlated to the morbidity of dental and skeletal fluorosis. High fluorine concentration in drinking water has endangered human health. [ABSTRACT FROM AUTHOR]

This paper presents the detection of sea surface temperature (SST) and salinity in the Gulf of Bohai Sea of China using thermal infrared (TIR) data of Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS). Both AVHRR and MODIS imageries are evaluated as main data sources for monitoring SST as a measure of upwelling's dynamic. The relationship between SST and salinity in the area is also discussed during 1997-2000 derived from AVHRR data and then examined using MODIS data of 2000. The obtained results indicated that both AVHRR and MODIS are useful to detect SST and salinity in the study area. [ABSTRACT FROM AUTHOR]