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Global surface temperature is predicted to increase by at least 1.5°C by the end of this century. However, the response of soil microbial communities to global warming is still poorly understood, especially in high-elevation grasslands. We therefore conducted an experiment on three types of alpine grasslands on the Qinghai-Tibet Plateau to study the effect of experimental warming on abundance and composition of soil microbial communities at 0-10 and 10-20 cm depths. Plots were passively warmed for 3 years using open-top chambers and compared to adjacent control plots at ambient temperature. Soil microbial communities were assessed using phospholipid fatty acid (PLFA) analysis. We found that 3 years of experimental warming consistently and significantly increased microbial biomass at the 0-10 cm soil depth of alpine swamp meadow (ASM) and alpine steppe (AS) grasslands, and at both the 0-10 and 10-20 cm soil depths of alpine meadow (AM) grasslands, due primarily to the changes in soil temperature, moisture, and plant coverage. Soil microbial community composition was also significantly affected by warming at the 0-10 cm soil depth of ASM and AM and at the 10-20 cm soil depth of AM. Warming significantly decreased the ratio of fungi to bacteria and thus induced a community shift towards bacteria at the 0-10 cm soil depth of ASM and AM. While the ratio of arbuscular mycorrhizal fungi to saprotrophic fungi (AMF/SF) was significantly decreased by warming at the 0-10 cm soil depth of ASM, it was increased at the 0-10 cm soil depth of AM. These results indicate that warming had a strong influence on soil microbial communities in the studied high-elevation grasslands and that the effect was dependent on grassland type.

Background and purposeEarly and accurate diagnosis of stroke by emergency medical service (EMS) paramedics is critical for reducing pre-hospital delays. The Los Angeles pre-hospital stroke screen (LAPSS) has been widely used as a validated screening tool for early identifying stroke patients by EMS paramedics. However, validation of LAPSS has never been performed in Chinese stroke population. This study is aimed to verify the LAPSS for early identifying stroke patients in a Chinese urban EMS.Methods76 paramedics of five urban first aid stations attached to Beijing 120 EMS were involved. The paramedics were trained by professionals to quickly screen patients based on LAPSS. Potential "target stroke" individuals who met the base LAPSS screen criteria were identified. Sensitivity and specificity analyses of the LAPSS were calculated.ResultsFrom June 10, 2009 to June 10, 2010, paramedics transported a total of 50,220 patients. 1550 patients who met the baseline screen criteria were identified as the potential "target stroke" population. 1130 patients had the completed LAPSS information datasheet and 997 patients were clinically diagnosed with stroke. The average time of completing the LAPSS was 4.3±3.0 minutes (median, 5 minutes). The sensitivity and specificity of the LAPSS in this study was 78.44% and 90.22%, respectively. After adjusting for age factor by excluding patients of >45 years old, the sensitivity was significantly increased to 82.95% with specificity unchanged.ConclusionThe paramedics of Beijing 120 EMS could efficiently use LAPSS as a screening tool for early identifying stroke patients. While the sensitivity of LAPSS in Chinese urban patient population was lower than those reported in previous LAPSS validation studies, the specificity was consistent with these studies. After excluded the item of "Age>45 years", the sensitivity was improved.

AIMS: To prospectively explore the association between non-high-density lipoprotein cholesterol (non-HDLC) and the risks of stroke and its subtypes. METHODS: A total of 95,916 participants (18-98 years old; 76,354 men and 19,562 women) from a Chinese urban community who were free of myocardial infarction and stroke at baseline time point (2006-2007) were eligible and enrolled in the study. The serum non-HDLC levels of participants were determined by subtracting the high-density lipoprotein cholesterol (HDLC) from total serum cholesterol. The primary outcome was the first occurrence of stroke, which was diagnosed according to the World Health Organization criteria and classified into three subtypes: ischemic stroke, intracerebral hemorrhage, or subarachnoid hemorrhage. The Cox proportional hazards models were used to estimate risk of stroke and its subtypes. RESULTS: During the four-year follow-up, we identified 1614 stroke events (1,156 ischemic, 416 intracerebral hemorrhagic and 42 subarachnoid hemorrhagic). Statistical analyses showed that hazard ratios (HR) (95% Confidence Interval: CI) of serum Non-HDLC level for total and subtypes of stroke were: 1.08 (1.03-1.12) (total), 1.10 (1.05-1.16) (ischemic), 1.03 (0.96-1.10) (intracerebral hemorrhage) and 0.83 (0.66-1.05) (subarachnoid hemorrhage). HR for non-HDLC refers to the increase per each 20 mg/dl. For total and ischemic stroke, the risks were significantly higher in the fourth and fifth quintiles of non-HDLC concentrations compared to the first quintile after adjusting the confounding factors (total stroke: 4(th) quintile HR=1.33 (1.12-1.59); 5(th) quintile HR = 1.36 (1.15-1.62); ischemic stroke: 4(th) quintile HR =1.34 (1.09-1.66); 5(th) quintile HR = 1.53 (1.24-1.88)). CONCLUSIONS: Our data suggest that serum non-HDLC level is an independent risk factor for total and ischemic stroke, and that higher serum non-HDLC concentrations are associated with increased risks for total stroke and ischemic stroke, but not for intracerebral and subarachnoid hemorrhage.