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Northwest China (NW China) falls within Arid Central Asia (ACA) and has a climate dominated by westerly winds, a fragile ecosystem, and a high sensitivity to climate change. Paleoenvironmental reconstructions of this region can assist in understanding the general processes contributing to environmental variation in such arid areas. This study examined a dated sedimentary core containing both peat and lacustrine deposits obtained from the shore of the Bosten Lake, NW China. The study aimed to reconstruct paleoenvironmental variations over the last 3,000 years and to explore the possible drivers of peatland development over the last millennium. An examination of grain size and δ13C was conducted to investigate lake level variation. The results showed that the lake level of the Bosten Lake declined gradually between 2,905 and 480 cal yr BP and increased thereafter, consistent with other records of the Bosten Lake. At a centennial timescale, the lake level was high under a wet climate during the Dark Age Cold Period (DACP), whereas it decreased significantly during the Medieval Warm Period (MWP). The inferred "cold and wet" and "warm and dry" patterns indicated climatic characteristics of a "westerlies-dominated climatic regime". In addition, the persistent decreasing lake level during the MWP resulted in Phragmites peatland initiation and development along the shores of the Bosten Lake. [ABSTRACT FROM AUTHOR]

Globally, lakes and reservoirs ecosystems are integral parts of ecological processes. Nevertheless, global warming is rapidly changing their function and sustainability, especially in the populated area of the northern hemisphere. Here we examined testate amoebae community and 10 environmental variables from 51 lakes and reservoirs across China and developed testate amoebae transfer functions for temperature based on both abundance- and biomass-datasets. A total of 169 testate amoebae taxa were identified. Our partial CCA analyses revealed that water temperature explained 5.15% (P = 0.006) and 5.57% (P = 0.008) of the total variance in testate amoebae abundance and biomass, respectively. The WA-PLS was the best model in abundance-based temperature transfer function (RMSEP = 2.87 °С, R2 = 0.60), whereas the MAT proved to be the best model for biomass-based temperature transfer function (RMSEP = 3.34 °С, R2 = 0.67). The application of all models should be carried out with suitable precautions. Our results suggested that freshwater testate amoebae could contribute to a better understanding of the ecological integrity and its vulnerability in inland aquatic environments. [ABSTRACT FROM AUTHOR]

Peatlands cover 3% of the earth’s land surface but contain 30% of the world’s soil carbon pool. Microbial communities constitute a crucial detrital food web for nutrient and carbon cycling in peatlands. Heterotrophic protozoans are considered top predators in the microbial food web; however, they are not yet well understood. In this study, we investigated seasonal dynamics in the community and the trophic structure of testate amoebae in four peatlands. Testate amoebae density and biomass in August were significantly higher than those in May and October. The highest density, 6.7 × 10 4 individual g −1 dry moss, was recorded in August 2014. The highest biomass, 7.7 × 10 2  μg C g −1 dry moss, was recorded in August 2013. Redundancy analyses showed that water-table depth was the most important factor, explaining over one third of the variance in fauna communities in all sampled seasons. High trophic position taxa dominated testate amoebae communities. The Shannon diversity index and community size structure index declined from August to October in 2013 and from May to October in 2014. These seasonal patterns of testate amoebae indicated the seasonal variations of the peatlands’ microbial food web and are possibly related to the seasonal carbon dynamics in Northeast Chinese peatlands. [ABSTRACT FROM AUTHOR]

Summary Objectives Zhengzhou, Kaifeng and Xinxiang, the cities in the north central region of Henan Province, suffered from many times floods from 2004 to 2009. We focused on dysentery disease consequences of floods and examined the association between floods and the morbidity of dysentery, based on a longitudinal data. Methods A generalized additive mixed model was conducted to examine the relationship between the monthly morbidity of dysentery and floods from 2004 to 2009 in the study areas. The relative risks (RRs) of the floods risk on the morbidity of dysentery were estimated in each city and the whole region. Results The RRs on dysentery were 11.47 (95% CI: 8.67–15.33), 1.35 (95% CI: 1.23–3.90) and 2.75 (95% CI: 1.36–4.85) in Kaifeng, Xinxiang and Zhengzhou, respectively. The RR on dysentery in the whole region was 1.66 (95% CI: 1.52–1.82). Conclusions Our study confirms that flooding has significantly increased the risk of dysentery in the study areas. Additionally, we observed that a sudden and severe flooding can contribute more risk to the morbidity of dysentery than a persistent and moderate flooding. Our findings have significant implications for developing strategies to prevent and reduce health impact of floods. [ABSTRACT FROM AUTHOR]

Abstract: V and N co-doped diamond-like carbon (DLC–VN) composite films were deposited on cemented carbide substrates by pulsed bias arc ion plating. The effects of V and N contents on the structures and properties of the films were investigated by X-ray photoelectron spectroscopy (XPS), Raman spectra, grazing incident X-ray diffraction (GIXRD), transmission electron microscopy (TEM) and nano-indentation, respectively. The as-deposited films consist of a DLC–VN nanocomposite, where VN nanograins are embedded in an amorphous carbon matrix. The V and N contents have significant influences on the relative proportion of VN with respect to DLC. A proper concentration of VN nanocrystals in DLC induces even the formation of nano-diamond. The DLC–VN films have higher hardnesses than pure DLC films, which could be attributed to the nanocomposite structure. [Copyright &y& Elsevier]

Peatlands are one of the most significant carbon reservoirs in the terrestrial ecosystem. Understanding past peatland carbon accumulation processes and their responses to varying external and internal forcing factors would help reveal the general development patterns of peatland ecosystems and provide useful insights into projecting the fate of carbon reservoirs into the future. In this paper, the basal ages of 17 peat cores were used to explore the lateral expansion processes of the Laolike peatland, northeast China. Two cores were selected to calculate carbon accumulation rates (CAR) and reconstruct moisture/precipitation records based on δ13C and grain size analyses. The basal ages show that the peatland was initiated at 12.1 cal kyr BP, then laterally expanded with its fastest rate occurring during the early Holocene, and reached its largest area around 6 cal kyr BP. The time-weighted mean CAR in the Laolike peatland ranged from 31.1 to 52.9 g C/m2/yr (with an average of 42 g C/m2/yr) during the Holocene. The peatland experienced a high CAR of 52.5 g C/m2/yr from 11.7 to 5 cal kyr BP, followed by a low CAR of 35.1 g C/m2/yr after 5 cal kyr BP. Both lateral expansion and vertical accretion are consistent with the summer insolation, climate seasonality, and the strength of the East Asia summer monsoon (EASM) over multi-millennium timescales, where the CAR correlated well with δ13C and grain size, implying moisture/precipitation might be the primary factors controlling carbon accumulation over millennium timescales. Local conditions, such as topography and hydrology, also played an important role in the process of peatland initiation and lateral expansion, as well as the discrepant CAR within the peatland. This study reveals the roles of climate and local conditions in peatland initiation, expansion, and CAR during the Holocene. In addition, we provide a window for a better understanding of the driving factors of peatland development in the temperate zones of the Northern Hemisphere. • Climate conditions are the primary control on the lateral expansion and vertical accretion of Laolike peatland over multi-millennium timescales. • Moisture/precipitation affects carbon accumulation of Laolike peatland over millennium timescales. • Local conditions play an important role in the lateral expansion and the internal differences of carbon accumulation rate. [ABSTRACT FROM AUTHOR]

Testate amoebae (TA) are a common and diverse group of protists and are especially abundant in peatlands. The structure of peatland TA communities is well correlated to surface moisture and water table depth (WTD). For that reason, TA are widely used as proxy indicators in ecological and palaeoecological studies. Peatlands are abundant across Asia, but the diversity and ecology of the TA that inhabit these systems are poorly documented. It is therefore unclear whether TA can be used as palaeohydrological indicators in the manner in which they commonly are in Europe and North-America. There is particular uncertainty as to the efficacy of this approach in the lower latitudes. We compiled existing and new data on testate amoebae from 1124 Sphagnum -dominated samples from 42 individual peatlands covering broad latitudinal (25°–66° N) and longitudinal (68°–129° E) ranges. Using a consensus taxonomic framework, we built a checklist of TA and developed TA-based hydrological transfer functions for Asian peatlands. The results showed that three models, weighted averaging (WA), weighted average partial least squares (WA-PLS), and maximum likelihood (ML), predicted similar WTD values for full samples, while the modern analogue technique (MAT) produced the strongest (R2 boot = 0.58) relationship between observed and estimated water-table depths (WTDs). Removing outlier samples improved the R2 values of observed vs. estimated WTDs, with ML then demonstrating the strongest predictive power (R2 boot = 0.68, RMSEP boot = 8.98 cm). The predictive capability of the developed WTD transfer function is comparable to equivalent models for Europe and North America and thus can be used for palaeohydrological reconstructions for boreal to subtropical peatlands in Asia. • A testate amoebae taxonomic checklist was compiled from Asian peatlands. • We developed continental scale testate amoeba-based hydrological transfer functions. • The water-table depth transfer functions can be used for paleohydrological reconstructions. [ABSTRACT FROM AUTHOR]

For vertical contact-separation-mode triboelectric nanogenerator (TENG), the hydrophobic surface is often used to improve the electrical output under high humidity condition. However, for sliding-mode TENG, the triboelectric effect is accompanied with the friction and wear of material, and whether the hydrophobic surface is beneficial to the durability as well as the stability of electrical output has been really ambiguous. In the paper, the pillar arrays with different pitches are fabricated through lithography, deep reactive ion etching and replication techniques to get the hydrophobic surface with different static contact angle. Based on the test platform with humidity control system, the effects of pillar pitch and normal force on the coefficient of friction, mass loss, and open-circuit voltage are investigated experimentally at different relative humidity condition. The results show that the effect of humidity on electrical output for sliding-mode TENG is different from that for vertical contact-separation-mode TENG. For a certain patterned surface of sliding-mode TENG, the coefficient of friction, short-circuit current and open-circuit voltage increase with the increasing relative humidity at first and diminish afterwards. The maximum values of them are achieved at 50% relative humidity. The mass loss diminishes with the increment of relative humidity. For surfaces with different pillar pitch, the coefficient of friction and open-circuit voltage decrease with the increasing pillar pitch, while the mass loss increases. Moreover, the decrease in pillar pitch, in which the contact angle of surface is increased, can improve the durability as well as the stability of output of sliding-mode TENG. In addition, although the greater normal force can enhance the stability of open-circuit voltage for sliding-mode TENG under humidity condition, the contact angle of surface will be reduced more obviously in the process of wear, speeding up the failure of hydrophobic surface. This study reveals the effect of hydrophobic surface on the durability as well as the stability of output for sliding-mode TENG and provides reference for texture design at different humidity conditions. Image 1 • The effect of humidity on output of sliding-mode TENG is different from that of vertical contact-separation-mode TENG. • The decrease in pillar pitch can improve the durability as well as the stability of output of sliding-mode TENG. • The greater normal force can enhance the stability of output, but it will worsen the durability of hydrophobic surface. [ABSTRACT FROM AUTHOR]

Although observational studies have shown an association between sex hormone-binding globulin (SHBG), testosterone (T) and cardiovascular diseases (CVD), controversy remains. In this study, we aim to explore the causal effects of SHBG and T on Coronary heart disease (CHD). We used univariable, network and multivariable mendelian randomization (MR) analysis to investigate the causal effect of SHBG and T on CHD. We performed inverse variance weighted (IVW) MR as the primary analysis, with the robustness of this approach further tested by other methods in sensitivity analysis. The SHBG and T were collected from the UK Biobank data, about 180,000 men aged 40 to 69 years. CHD was collected from CARDIoGRAMplusC4D 1000 Genomes-based GWAS, which was a meta-analysis including 48 studies and involving 60,801 CHD cases and 123,504 controls. Using univariable MR-IVW, the results suggested that a one standard deviation (SD) increase in SHBG, the risk of CHD decreased by approximately 14% (OR (95% CI): 0.86(0.76,0.97)), and that a SD increase in total testosterone (TT), the risk also decreased, approximately 8% (OR (95% CI): 0.92(0.85,0.99)). Multivariable MR showed that both SHBG and TT had no direct causal effect with CHD (a SD increase in SHBG: OR (95% CI):0.75(0.57,1.00), P = 0.053; a SD increase in TT: OR (95% CI): 1.05(0.90,1.22), P = 0.53). In the network MR analysis, the results suggested that TT might act as mediator in the causal pathway from SHBG to CHD and account for 93% of the total effect of SHBG on CHD, and that SHBG might be a mediator in the causal pathway from TT to CHD and account for 67% of the total effect of TT on CHD. Genetically predicted SHBG and TT were negatively correlated with CHD in both univariable and network MR, which may provide a causal explanation behind the observed conclusion. In addition, TT and SHBG had a bidirectional causal effect. Further work is required to disentangle the downstream effects of SHBG/TT on CHD and the molecular pathways involved, as the simultaneous regulation of SHBG and TT may make it a viable strategy for the prevention or treatment of CHD. • Multivariable MR showed that both SHBG and TT had no direct causal effect with CHD (a SD increase in SHBG: OR (95%CI):0.75(0.57,1.00), P = 0.053; a SD increase in TT: OR (95%CI): 1.05(0.90,1.22), P = 0.53). • In the network MR analysis, the results suggested that TT might act as mediator in the causal pathway from SHBG to CHD and account for 93% of the total effect of SHBG on CHD, and that SHBG might be a mediator in the causal pathway from TT to CHD and account for 67% of the total effect of TT on CHD. [ABSTRACT FROM AUTHOR]

• Hillslope topography is essential for local hydrology and peatland formation. • Microtopographic patterning enhances the positive water balance of the peatland. • Feedback between plant growth and pool development reinforces the stability of the peatland. Some sloping peatlands in northern regions often develop surface microtopographic patterns to maintain their water balance and ecosystem functioning. However, we do not know whether and how spatial patterning would influence the water balance and peat formation of permafrost-affected peatlands in relatively dry regions. Here we used data from the field observations and Unmanned Aerial Vehicle (UAV) survey of a slope peatland at an elevation of around 4800 m in the hinterland of the Qinghai-Tibetan Plateau (QTP) to document and understand the topographic controls of water balance and vegetation growth. Our terrain analysis result shows that the peatland—located on the middle section of a hillslope—has a gentle slope of 5.6° ± 2.5°, while the non-peatland upper section has a steep slope of 12° ± 4.5°. The great upstream catchment area and the presence of shallow impermeable permafrost likely create a saturated condition for peat formation. Our UAV results show obvious spatial patterning of abundant pools and ridges across this peatland, and pool sizes and ridge abundance increase with increasing slopes, suggesting that slope-controlled water flow gradient is the main driver of ridge formation and that ridges is to slow down the runoff. UAV-derived greenness values show a positive relationship with the total pool extent locally (R2 = 0.60) and decrease with increasing distance from the individual pools, suggesting sensitive responses of vegetation growth to surface moisture. Thus, enhanced vegetation growth and likely resultant great peat accumulation immediately around pools potentially further differentiate surface microtopography, strengthening the pool stability. We conclude that the local slope gradient, surface patterning (pools and ridges) and permafrost interact together to regulate water flow and maintain water balance, which in turn regulate the vegetation growth, peat accumulation and peatland stability. Our study implies that the delicate water balance maintained partly by microtopography is sensitive to climate change—especially potential extreme hydroclimate events—and natural and human-induced disturbances that may modify the surface patterning and weaken the peatland's stability, affecting the carbon sequestration ability of this type of peatlands. [ABSTRACT FROM AUTHOR]

A novel polyaniline (PANI)/Eu3+ nanofiber sensing film was prepared in the presence of Eu(NO 3) 3 which serves as structure-directed agent. The morphological, component, crystallinity and electrochemical properties were carried out by using Scanning Electron Microscope (SEM), Energy-Dispersive X-ray (EDX), Fourier Transform Infrared spectroscopy (FT-IR), X-Ray Diffraction (XRD) and Brunauer-Emmett-Teller (BET) techniques. The results indicated the nanofiber-like network with porous structure appeared in the PANI embedded by Eu3+ ions, thereby leading to large specific surface area. Furthermore, the PANI/Eu3+ nanofibers were grown onto the inner wall of capillary glass to form the tube sensor. By the sensing measurements, this tube sensor enabled the detection of low-volume (0.3 mL) NH 3 for response 435% at concentration of 0.25 ppm with a short response time (5 s) and recovery time (5 s), and the performances of reproducibility and selectivity were also excellent. The above results demonstrated the potential application of PANI/Eu3+ tube sensor for low-volume NH 3 gas. Image 1 • A PANI/Eu3+ tube sensor was designed for the trace NH 3 detection. • Eu3+ ions dopant as structure-directed agent promoted the formation of nanofiber-like network and porous structure. • The film was grown onto the inner wall of silica glass capillary tube (length 7.5 cm, inner diameter 1 mm). • The low-volume (0.3 mL) NH 3 can be detected with rapid response (435%, 0.25 ppm) with response/recovery time (5 s/5 s). [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]

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]