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• Soil PLFAs increased with altitude in the sedge dominated peatlands but decreased with altitude in the shrub/ Sphagnum dominated peatland. • Soil microbes were co-limited by C and P with the limitations greater in the sedge dominated peatlands than in the shrub/ Sphagnum dominated peatlands. • The P limitation was greater at the high altitudes than that at the low altitudes. • Soil PLFAs and community was regulated by soil physical properties and nutrients, respectively. • The C and P limitation was regulated by soil physical properties and nutrient ratios, respectively. Soil microbes regulate the storage of carbon (C) in peatlands, which is facilitated by nutrients. To date, few researchers have examined the spatial distribution of soil microbial biomass, microbial community structure, and their metabolic nutrient limitations in mountain peatlands at different altitudes. This study aimed to improve the knowledge of how and why soil microbial biomass and their metabolic nutrient limitations varied with altitude. We investigated the phospholipid fatty acids (PLFAs) and enzymatic stoichiometry in surface (0–20 cm) and subsurface (20–50 cm) soil from peatlands with different types of vegetation in the Changbai Mountains. Overall, the soil microbial PLFAs were higher in the sedge-dominated peatlands than in the shrub/ Sphagnum- dominated peatlands. The soil microbial PLFAs in the sedge-dominated peatlands were elevated at high altitudes but decreased with altitude in the shrub/ Sphagnum- dominated peatlands. The soil fungal/bacterial ratios (F/B) in the surface soil increased with altitude in the sedge-dominated peatlands but not in the shrub/ Sphagnum- dominated peatlands. The Gram-positive/Gram-negative bacteria ratios (G+/G−) in the surface soil decreased with altitude in the sedge-dominated and shrub/ Sphagnum- dominated peatlands. The soil F/B ratios were higher, but the G+/G− ratios were lower in the shrub/ Sphagnum- dominated peatlands than in the sedge-dominated peatlands. The soil pH and nutrient ratios explained most of the differences in soil bacterial and fungal PLFAs, respectively. However, the total nutrients of soil were the primary regulators of soil F/B and G+/G−. The soil microbial activities suffered from C- and phosphorus (P)- limitations in the mountain peatlands. The limitations were worse in the shrub/ Sphagnum- dominated peatlands than in the sedge-dominated peatlands. The P limitations were greater at high altitude than at low altitude in both types of peatlands. The C and P limitations on soil microbial metabolism were primarily controlled by soil physical properties and nutrient ratios, respectively. [ABSTRACT FROM AUTHOR]

• Peatland degradation caused a significant loss of testate amoeba (TA) biodiversity. • Unexpectedly, this loss was accompanied by an increase in TA biosilicification. • TA biodiversity was not coupled to protozoic biogeochemical silicon (Si) cycling. • New insights into microbial biogeochemical Si cycling on a continental scale. Anthropogenic peatland degradation is a global threat. As peatlands store large amounts of carbon (C) their potential for mitigation of climate change has been emphasized recently. Global C cycling is linked to silicon (Si) fluxes from the continents into the oceans. These fluxes in turn are driven by biosilicification, the incorporation of inorganic Si into living organisms, in terrestrial ecosystems. Biosilicification by testate amoeba (TA) communities and its potential for Si cycling has been highlighted since the beginning of the 21st century. However, the effects of peatland degradation on TA biodiversity and corresponding protozoic biosilicification on a continental scale remained unresolved so far. We show that TA biodiversity in Asian peatlands is strongly affected by the grade of human impact. This biodiversity decline was accompanied by an unexpected increase in protozoic biosilicification. Our findings provide new insights into the interactions between the biodiversity of soil microorganisms and biogeochemical Si cycling. [ABSTRACT FROM AUTHOR]

Objectives To explore the longitudinal effect of metabolic syndrome (MetS) and its components on the development of non-alcoholic fatty liver disease (NAFLD) and to evaluate the significance of MetS and its components as early markers of NAFLD risk in a northern urban Han Chinese population. Materials and methods A total of 15,791 cohort members without NAFLD at baseline were included in the current study between 2005 and 2011. The baseline characteristics of the cohort were compared by MetS status at baseline and NAFLD status after follow-up. Cox proportional hazards models were used to estimate the unadjusted or adjusted hazard ratios (HRs) for development of NAFLD among individuals with MetS compared with individuals without MetS at baseline. Results During 51,652 person-years of follow-up, 3913 (24.78%) new cases of NAFLD occurred between 2005 and 2011. In the unadjusted model, the HR (95% confidence interval [CI]) for NAFLD was 2.51 (2.30, 2.73). After adjusting for gender, age, diet, smoking status, and regular exercise, the HR was 1.94 (1.78, 2.13). Gender differences were observed, with adjusted HRs (95% CIs) of 1.89 (1.71, 2.09) and 1.72 (1.43, 2.07) among males and females, respectively. Compared with individuals without MetS components, the HRs were 1.92 (1.76, 2.09), 2.64 (2.40, 2.90) and 3.51 (3.15, 3.91) for individuals with one, two, or three or more MetS components, respectively. Moreover, participants with obesity or hyperlipidemia had a higher risk of NAFLD than patients with hypertension or hyperglycemia, with HRs of 2.03 (1.83, 2.25) for obesity, 1.94 (1.72, 2.19) for hyperlipidemia, and 3.01 (2.68, 3.37) for these factors in combination. Conclusion The present study indicates that MetS and its components independently predict the risk of NAFLD in a northern urban Han Chinese population and suggests that people with MetS or its component should initiate lifestyle changes to prevent the development of NAFLD. [ABSTRACT FROM AUTHOR]

Objectives: To explore the relationship between non-alcoholic fatty liver disease (NAFLD) and the metabolic syndrome (MetS), and evaluate the value of NAFLD as a marker for predicting the risk of MetS in a large scale prospective cohort from northern urban Han Chinese population. Materials and Methods: A total of 17,920 MetS-free at baseline cohort members was included in the current study between 2005 and 2011. The baseline characteristics of the cohort were compared by NAFLD status at baseline, MetS status after follow-up. Cox proportional hazards models were used to estimate the unadjusted or adjusted hazard ratios (HRs) for NAFLD at baseline predicting the risk of MetS. Results: 2,183 (12.18%) new cases of MetS occurred between 2005 and 2011. In unadjusted model, HRs (95% CIs) for NAFLD predicting MetS was 3.65 (3.35, 3.97). After adjusting the confounding factors of age, gender, the metabolic factors, smoke and exercise, the HRs (95% CIs) was 1.70 (1.55, 1.87). Gender difference was observed, adjusted HRs (95% CIs) of NAFLD for predicting MetS were 2.06(1.72, 2.46) and 1.55(1.39, 1.72) in female and male population, respectively. Moreover, 163 participants developed MetS among participants without any MetS component at baseline, and its adjusted HRs was still significant, 1.87 (1.12, 3.13). Conclusion: The present study indicates that NAFLD is an independent risk factor for predicting the risk of MetS in northern urban Han Chinese population, and the people with NAFLD should initiate weight and dietary control to prevent the occurrence of MetS. [ABSTRACT FROM AUTHOR]

Xinxiang, a city in Henan Province, suffered from frequent floods due to persistent and heavy precipitation from 2004 to 2010. In the same period, dysentery was a common public health problem in Xinxiang, with the proportion of reported cases being the third highest among all the notified infectious diseases. We focused on dysentery disease consequences of different degrees of floods and examined the association between floods and the morbidity of dysentery on the basis of longitudinal data during the study period. A time-series Poisson regression model was conducted to examine the relationship between 10 times different degrees of floods and the monthly morbidity of dysentery from 2004 to 2010 in Xinxiang. Relative risks (RRs) of moderate and severe floods on the morbidity of dysentery were calculated in this paper. In addition, we estimated the attributable contributions of moderate and severe floods to the morbidity of dysentery. A total of 7591 cases of dysentery were notified in Xinxiang during the study period. The effect of floods on dysentery was shown with a 0-month lag. Regression analysis showed that the risk of moderate and severe floods on the morbidity of dysentery was 1.55 (95% CI: 1.42–1.670) and 1.74 (95% CI: 1.56–1.94), respectively. The attributable risk proportions (ARPs) of moderate and severe floods to the morbidity of dysentery were 35.53 and 42.48%, respectively. This study confirms that floods have significantly increased the risk of dysentery in the study area. In addition, severe floods have a higher proportional contribution to the morbidity of dysentery than moderate floods. Public health action should be taken to avoid and control a potential risk of dysentery epidemics after floods. [ABSTRACT FROM AUTHOR]

Studying the locomotive behavior of animals has the potential to inspire the design of the mechanism and gait patterns of robots ('bio-inspired robots'). The kinematics characteristics of a spider ( Ornithoctonus huwena), including movement of the legs, movement of the center of mass (COM) and joint-rotation angle, were obtained from the observation of locomotion behaviors recorded by a three-dimensional locomotion observation system. Our results showed that one set of the stance phase consists of four legs, which were leg-1 and leg-3 on one side and leg-2 and leg-4 on the other side. Additionally, two sets of the stance phase comprised eight legs alternately supporting and driving the motion of the spider's body. The spider primarily increased its movement velocity by increasing stride frequency. In comparison to other insects, the spider, O. huwena, has superior movement stability. The velocity and height of COM periodically fluctuated during movement, reaching a maximum during alternation of leg phase, and falling to a minimum in the steady stance phase. The small change in deflection angle of the hind-leg was effective in driving locomotion, whereas each joint-rotation angle of the fore-leg changed irregularly during locomotion. This research will help in the design of bio-inspired robots, including the selection of gait planning and its control. [ABSTRACT FROM AUTHOR]

Abstract: Pulsed bias arc ion plating was used to form Cr-nitride films on stainless steel as bipolar plate of proton exchange membrane fuel cell. Surface micrograph, film thickness, film composition, corrosion resistance, interfacial conductivity and contact angle with water of the sample obtained at the optimal flow rate of N2 were investigated. The atomic ratio of Cr to N was close to 2:1 and the CrN phase with crystal planes of (111), (200), (220) and (311) was found in the film. Potentiodynamic and potentiostatic tests showed that the corrosion resistance of the bipolar plate sample was greatly enhanced. The contact resistance between the bipolar plate sample and Toray carbon paper was about two orders of magnitude lower than that of 316L stainless steel. The contact angle of the sample with water was 95°, which is beneficial for water management in fuel cells. [Copyright &y& Elsevier]

• A perovskite-based NH 3 /amine sensor via the "turn-on" fluorescence process. • The sensor is built by depositing the MAPbBr 3 on the mp-TiO 2 layer. • Excellent NH 3 response (72% at 5 ppm, and 988% at 100 ppm, respectively). • Favorable reversibility, high gas selectivity, humidity insensitivity, and regeneration. • NH 3 -induced trap passivation and electron transfer blocking. Recently, lead halide perovskites have attracted great interest in toxic gas detection, but as gas sensor, it is still a challenge to achieve their high-performance. Here, we propose a novel "turn-on" fluorescence NH 3 /amine vapor sensor by depositing the CH 3 NH 3 PbBr 3 (MAPbBr 3) on the mesoporous TiO 2 (mp-TiO 2) layer. The fluorescence intensity of the sensor increases rapidly within seconds upon exposure to NH 3 gas (72 % at 5 ppm and 988 % at 100 ppm, respectively) with excellent reversibility, high gas selectivity, humidity insensitivity, and regeneration. Moreover, the sensor can be further used for detecting various amine vapors, including methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, and decylamine. We presumed the "turn-on" fluorescence sensing mechanism is that the trace NH 3 or amine molecules could decrease the surface trap defects and facilitate the formation of passivation layer. It will impede the electron-injection into mp-TiO 2 , which induces the radiative electron-hole recombination and fluorescence enhancement. This research demonstrates that it is feasible to design a "turn-on" fluorescence gas sensor based on the mp-TiO 2 -based perovskite. [ABSTRACT FROM AUTHOR]