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Yushenfu mining area is located in an ecological fragile area in western China, the coal seam of which is the Jurassic Yan'an Formation. The Jurassic Yan'an Formation contains five minable coal seams, the top layer of which is thick, covered by shallow overburden and located under aquifers. Therefore, the mining induced water flowing fractured zone can easily extend to the aquifers of both the Quaternary Sarahu and Jurassic Zhiluo Formation. This would result in a series of negative hydrological and ecological effects, including groundwater leakage, groundwater lowering, furtherly causing surface vegetation withering and dying, surface water body reduction, spring drying out, and water flow of river being decreased substantially. To solve these environmental problems, several technologies have been carried out by Chinese scientists, one of which is water-preserved coal mining. This paper presents a review of the origin, definition and development of water-preserved coal mining, and its applications in Yushenfu mining area. The applicable conditions, research contents, research methodology, and technical foundation of water-preserved coal mining are addressed in this paper. The future research focuses regarding water-preserved coal mining in China are also discussed in this paper. Its results serve as a guide for selecting the methods to be preferred for mining in case the geological conditions, roof overburden structure and coal mining process are similar to Yushenfu mining area. [ABSTRACT FROM AUTHOR]

The Great Western Development Strategy (GWDS) is a long term national campaign aimed at boosting development of the western area of China and narrowing the economic gap between the western and the eastern parts of China. The Strategic Environmental Assessment (SEA) procedure was employed to assess the environmental challenges brought about by the western development plans. These plans include five key developmental domains (KDDs): water resource exploitation and use, land utilization, energy generation, tourism development, and ecological restoration and conservation. A combination of methods involving matrix assessment, incorporation of expert judgment and trend analysis was employed to analyze and predict the environmental impacts upon eight selected environmental indicators: water resource availability, soil erosion, soil salinization, forest destruction, land desertification, biological diversity, water quality and air quality. Based on the overall results of the assessment, countermeasures for environmental challenges that emerged were raised as key recommendations to ensure ecological security during the implementation of the GWDS. This paper is intended to introduce a consensus-based process for evaluating the complex, long term pressures on the ecological security of large areas, such as western China, that focuses on the use of combined methods applied at the strategic level. [ABSTRACT FROM AUTHOR]

In this study, we use the spatial econometric model with panel data to investigate the mechanism and effect of economic growth on public health in Western China. The research results show that the spatial agglomeration effects are significant on the public health performance in Western China. Economic growth significantly promotes local public health status during the range of our sample data, leading to reduced human mortality. Environmental pollution significantly increases human mortality not only in local province but also in neighboring provinces. As GRP per capita of a province continues to increase, the impact of environmental pollution on increasing human mortality has diminished gradually. Moreover, improving the level of technological progress and healthcare services significantly improve public health. Interestingly, as GRP per capita of a province continues to increase, the impact of technological progress and healthcare services on decreasing human mortality has gradually weakened. [ABSTRACT FROM AUTHOR]

Previous reports have described close relationships between sarcopenia and either visual impairment or depression, but there have been few analyses investigating the association between sarcopenia and the coexistence of both visual impairment and depression. Herein, we sought to explore the associations between sarcopenia and comorbid depressive symptoms and visual impairment among older females. A cross-sectional analysis of females between the ages of 50 and 95 (n = 2454) from the West China Health and Aging Trend (WCHAT) study was conducted. Patient muscle mass was assessed via a bioimpedance-based approach using an InBody 770 device, while muscle strength was estimated based on handgrip strength as quantified with a digital grip strength dynamometer. Depressive systems were evaluated with the 15-item Geriatric Depression Scale (GDS-15), and a questionnaire was employed to evaluate patient visual functionality. Associations between sarcopenia and comorbid depressive status and visual impairment were explored through logistic regression analyses. Comorbid depressive symptoms and visual impairment were observed in 6.2% of the women included in this study, while 18.9% suffered from sarcopenia. Following adjustment for covariates, relative to normal controls, study subjects with only depression (OR=1.45, 95%CI=1.04–2.02), only visual impairment (OR=1.69, 95%CI=1.27–2.26), or comorbid depression and visual impairment (OR=1.76, 95% CI=1.16–2.67) exhibited a higher risk of sarcopenia. These results suggest that comorbid depression and visual impairment are linked to the prevalence of sarcopenia in older Chinese women. As such, further efforts to screen older women for these two comorbid conditions may thus be necessary. [ABSTRACT FROM AUTHOR]

Objectives: Sarcopenia is a condition associated with progressive loss of skeletal muscle mass and function resulting in substantial negative health outcomes and disability in older adults. It is thus important that sarcopenia-related risk factors be explored. The present study was based upon the Asian Working Group on Sarcopenia 2019 (AWGS2019) criteria to assess whether vitamin D levels are a risk factor associated with sarcopenia in various ethnic groups in western China. Design: Cross-sectional study. Setting: Communities in Yunnan, Guizhou, Sichuan, and Xinjiang provinces. Participants: We included 4236 individuals that were 50 years of age or older from the West China Health and Aging Trend (WCHAT) study. Measurements: An InBody 770 instrument was used for bioimpedance-based analyses of muscle mass, while a digital grip strength dynamometer was used for handgrip strength-based measurements of muscle strength. Physical performance was assessed based upon gait speed over 4 m. Other secondary variables were additionally analyzed as potentially relevant risk factors. Results: Sarcopenia affected an estimated 22.45% of studied individuals who were 50 years of age or older, with respective prevalence rates in the < 60, 60–64, 65–79, and ≥80 age groups of 11.78%, 19.44%, 32.65%, and 67.97%. Rates in males and females were 26.66% and 20.05%, respectively. In males, a significant difference in vitamin D levels was detected when comparing individuals with and without sarcopenia, although no such relationship was detected in females. Following adjustment for confounding variables, binary logistic regression analyses revealed that inadequate vitamin D was able to independently predict sarcopenia risk only in males (OR=1.875,95%CI: 1.109–3.169, P=0.019). Conclusions: Among middle-aged and older adults of multiple ethnicities in western China, we found that inadequate vitamin D was an independent predictor of sarcopenia risk specifically in males. [ABSTRACT FROM AUTHOR]

In cold regions, recurrent freeze–thaw action and loading conditions are important factors affecting the long-term durability of natural rocks in engineering systems. This study explores the effects of freeze-thaw action and strain rate on the mechanical behavior of the sandstone retrieved from Urumqi areas of western China. In addition, a decay function model was built for predicting the mechanical degradation and durability of the tested rock based on the P-wave velocity results. The results suggest that the mechanical properties of samples under either static or dynamic loading decrease with the increase in freeze-thaw action. However, the enhancement influence of the strain rate on dynamic compression strength and deformation modulus under freeze-thaw action still exists and increases with the increasing strain rate. Moreover, under the same dynamic loading, increasing in freeze-thaw action can aggravate the fragmentation degree of the tested sample. The proposed decay model is in good agreement with the data measured in the tests, and the model can accurately describe the influences of freeze-thaw action and strain rate on deterioration responses of the rock. Thus, this decay model can be used to obtain better predictions of the long-term durability of tested rocks under the effect of freeze–thaw action and strain rate. [ABSTRACT FROM AUTHOR]

Objective: To study risk factors for tuberculosis (TB) patients with diabetes mellitus (DM) living in Western China and analyze the baseline characteristics and clinical data of those patients for developing an effective screening strategy. Methods: We enrolled 3548 TB patients who were admitted to our hospital from 2014 to 2018. The baseline characteristics and clinical data of TB patients with and without DM were compared. Besides, risk factors were presented, and their effects on TB patients with and without DM were analyzed. Results: The prevalence of DM among TB patients was 7.7%, which increased with elevation of the patients' age, and 63.1% of TB patients with DM had hemoglobin A1c (HbA1c) ≥ 7.0%. The prevalence of DM in the Han patients with TB was the highest (8.8%), which was roughly three times higher than that in the Tibetan patients with TB (3.0%). In the multivariate logistic regression analysis, elevated values of the patients' age (odds ratio (OR), 1.047 (1.033–1.062, p < 0.01), blood pressure (OR, 1.735 (1.101–2.734), p = 0.04), proportion of cavity in pulmonary TB (PTB) (OR, 2.167 (1.272–3.656), p = 0.004), fasting blood glucose (OR, 2.248 (1.997–2.555), p < 0.001), erythrocyte sedimentation rate (ESR) (OR, 1.007 (1.001–1.012), p = 0.027), and proportion of patients with PTB (OR, 2.426 (1.425–4.104), p < 0.001) were significantly associated with increased prevalence of DM in TB patients. For evaluation of the model, the receiver operating characteristic (ROC) curve was plotted, in which the area under the curve (AUC) value of 0.924 was obtained for an optimal cutoff value of 0.052. The re-sampling method was utilized to verify the regression model, and the mean squared error (MSE) was 0.00026. Conclusions: The prevalence of DM in TB patients is high and is associated with severe clinical symptoms. Therefore, early screening of DM for TB patients is highly recommended. [ABSTRACT FROM AUTHOR]

Variations of surface air temperature (SAT) are key in affecting the hydrological cycle, ecosystems and agriculture in western China in summer. This study assesses the seasonal forecast skill and reliability of SAT in western China, using the GloSea5 operational forecast system from the UK Met Office. Useful predictions are demonstrated, with considerable skill over most regions of western China. The temporal correlation coefficients of SAT between model predictions and observations are larger than 0.6, in both northwestern China and the Tibetan Plateau. There are two important sources of skill for these predictions in western China: interannual variation of SST in the western Pacific and the SST trend in the tropical Pacific. The tropical SST change in the recent two decades, with a warming in the western Pacific and cooling in the eastern Pacific, which is reproduced well by the forecast system, provides a large contribution to the skill of SAT in northwestern China. Additionally, the interannual variation of SST in the western Pacific gives rise to the reliable prediction of SAT around the Tibetan Plateau. It modulates convection around the Maritime Continent and further modulates the variation of SAT on the Tibetan Plateau via the surrounding circulation. This process is evident irrespective of detrending both in observations and the model predictions, and acts as a source of skill in predictions for the Tibetan Plateau. The predictability and reliability demonstrated in this study is potentially useful for climate services providing early warning of extreme climate events and could imply useful economic benefits. [ABSTRACT FROM AUTHOR]

Four Zr-in-rutile thermometry calibrations are applied to eclogites from Western China. Here, we show that if rutile grows in equilibrium with Qtz and Zrn, and is isolated inside garnet, it preserves its Zr composition and does not undergo compositional change due to cation exchange with the host garnet. It thus preserves the composition for the P– T conditions of its formation and the growth zoning of the host garnet. For the HP/UHP metamorphic temperature, the Tomkins et al. (J Metamorph Geol 25:703–713, ) calibration yields temperatures that agree well with previous studies, whereas the other three calibrations (Zack et al. in Contrib Mineral Petrol 148:471–488, ; Watson et al. in Contrib Mineral Petrol 151:413–433, ; Ferry and Watson in Contrib Mineral Petrol in 154:429–437, ), which do not include a pressure correction, give systematically lower temperatures. Zr contents of rutile inclusions within garnet show systematic decrease from garnet core to rim. The rutile inclusions in garnet rims contain the lowest Zr content, similar to that in the matrix. Analyses confirm that the pressure plays a significant role in modifying the primary temperature dependence of the Zr content of rutile. Rutiles trapped in garnets are unable to re-equilibrate easily during retrogression, but those in the matrix can do so, providing retrograde P– T path information. [ABSTRACT FROM AUTHOR]

The dry-wet variability in western China and its spatiotemporal structure during the last 4–5 centuries was examined using 24 climate proxies from sediments, ice cores, historical documents, and tree rings. Spatial patterns and temporal evolutions of dryness and wetness were not only extracted from the proxy data using rotated empirical orthogonal function (REOF) analysis for the last 4 centuries, but also for instrumental data in the last 40 years. The leading five REOF modes indicate that 5 dry-wet variation centers exist in western China. Moreover, long-term variability in dryness and wetness is seen on long (centennial) to short (inter-decadal) timescales. An out-of-phase relationship for the inter-decadal variation was observed between the Hetao-upper Yangtze River region and north Xinjiang, indicating influences on dry-wet variations of the East Asian summer monsoon and the westerly winds over the two regions, respectively. A particularly long dry spell was found in the central Tibetan Plateau in the 19th century. A predominance of wet decades in the last 4 centuries was found in the arid and Hetao regions. Three regional dry-wet series with annual resolution in north Xinjiang, the upper Yellow River valley, and the Hetao area were constructed for analyses of the last 500 years. Dry-wet oscillations with periodicities of 16, 50, and 150 years in north Xinjiang, 50 years in the upper Yellow River valley, and 70–80 years in the Hetao region were identified by wavelet analysis. In general, these periods correspond to large-scale oscillations found in the climate system, are mainly related to ocean-atmosphere interaction. [ABSTRACT FROM AUTHOR]