In view of future changes in climate, it is important to better understand how differ-

In natural environments, kinetics of As(V) sequestration/release is usually coupled with dynamic Fe mineral transformation, which is further influenced by the presence of natural organic matter (NOM). Previous work mainly focused on the interactions between As(V) and Fe minerals. However, there is a lack of both mechanistic and quantitative understanding on the coupled kinetic processes in the As(V)-Fe mineral-NOM system. In this study, we investigated the effect of humic acids (HA) on the coupled kinetics of ferrihydrite transformation into hematite/goethite and sequestration of As(V) on Fe minerals. Time-resolved As(V) and HA interactions with Fe minerals during the kinetic processes were studied using aberration-corrected scanning transmission electron microscopy, chemical extractions, stirred-flow kinetic experiments, and X-ray absorption spectroscopy. Based on the experimental results, we developed a mechanistic kinetics model for As(V) fate during Fe mineral transformation. Our results demonstrated that the rates of As(V) speciation changes within Fe minerals were coupled with ferrihydrite transformation rates, and the overall reactions were slowed down by the presence of HA that sorbed on Fe minerals. Our kinetics model is able to account for variations of Fe mineral compositions, solution chemistry, and As(V) speciation, which has significant environmental implications for predicting As(V) behavior in the environment.

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We developed a unifying model for the kinetics of heavy metal dissociation from natural organic matter (NOM) in this study. The kinetics model, integrated with the equilibrium model WHAM 7, specifically considered metal ion reactions with various NOM sites formed by the carboxylic and phenolic sites. The association and dissociation rate coefficients for metal reactions with various NOM sites were constrained by WHAM predicted equilibrium distribution coefficients at specific reaction conditions. We developed the relationship for the dissociation rate coefficients among different binding sites for each metal, which was internally constrained by the metal binding constants. The model had only one fitting parameter, the dissociation rate coefficient for the metal complexes formed with two weak carboxylic sites, and all other parameters were derived from WHAM 7. The kinetic data for metal dissociation from NOM were collected from the literature, and the model was able to reproduce most of relevant data analyzed. The bidentate complexes appeared to be the predominated species controlling metal dissociation under most environmental conditions. The model can help to predict the reactivity and bioavailability of heavy metals under the impact of multiple competing ligands including NOM.

The 5L index score is more discriminative than the 3L index score in T2DM patients and therefore is preferable for use in this population.

Winter snow is an important driver of tree growth in regions where growing‐season precipitation is limited. However, observational evidence of this influence at larger spatial scales and across diverse bioclimatic regions is lacking. Here, we investigated the interannual effects of winter (here defined as previous October to current February) snow depth on tree growth across temperate China over the period of 1961–2015, using a regional network of tree ring records, in situ daily snow depth observations, and gridded climate data. We report uneven effects of winter snow depth on subsequent growing‐season tree growth across temperate China. There shows little effect on tree growth in drier regions that we attribute mainly to limited snow accumulation during winter. By contrast, winter snow exerts important positive influence on tree growth in stands with high winter snow accumulation (e.g., in parts of cold arid regions). The magnitude of this effect depends on the proportion of winter snow to pre‐growing‐season (previous October to current April) precipitation. We further observed that tree growth in drier regions tends to be increasingly limited by warmer growing‐season temperature and early growing‐season water availability. No compensatory effect of winter snow on the intensifying drought limitation of tree growth was observed across temperate China. Our findings point toward an increase in drought vulnerability of temperate forests in a warming climate.

Study Objectives: To determine the associations of self-reported sleep quality and duration with health-related quality of life (HRQOL) in older Chinese. Methods: We analyzed community-based cross-sectional data of 5,539 individuals aged 60 years and older in the Weitang Geriatric Disease Study. Information of sleep quality and duration were self-reported through participants' responses to predefined questions; HRQOL data were collected by using the European Quality of Life-5 Dimensions (EQ-5D). We estimated the associations of sleep quality and duration with the EQ-5D index and visual analog scale (VAS) scores using linear regression models. The associations between sleep quality and duration and EQ-5D-detected health problems were modeled using logistic regression. Results: In multiple linear models adjusting sociodemographic factors, health conditions, and lifestyle habits, both EQ-5D index and VAS scores declined with deterioration of sleep quality. The coefficients for poor and intermediate sleep quality were −0.053 (95% confidence interval [CI]:−0.065, −0.042) and −0.022 (95% CI: −0.030, −0.013), respectively, in relation to EQ-5D index score. They were −5.2 (95% CI: −6.7, −2.4) and − 3.8 (95% CI: −4.9, −2.7) in modeling the EQ-5D VAS score. HRQOL declined as sleep duration decreased below 7.01 hours or exceeded 8.01 hours, though most of the associations did not reach statistical significance. In multiple logistic models, poor sleep quality was associated with problems of mobility, pain/discomfort, and anxiety/ depression; short sleep duration was associated with mobility problems. Conclusions: Poor sleep quality and extreme sleep durations appeared to be negatively associated with HRQOL in older Chinese adults. Keywords: China, EQ-5D, health-related quality of life, older adults, sleep duration, sleep quality Citation: Pan CW, Cong X, Zhou HJ, Li J, Sun HP, Xu Y, Wang P. Self-reported sleep quality, duration, and health-related quality of life in older Chinese: evidence from a rural town in Suzhou, China.

Interannual air temperature variability has changed over some regions in Northern Hemisphere (NH), accompanying with climate warming. However, whether and to what extent it regulates the interannual sensitivity of vegetation growth to temperature variability (i.e., interannual temperature sensitivity)—one central issue in understanding and predicting the responses of vegetation growth to changing climate—still remains poorly quantified and understood. Here we quantify the relationships between the interannual temperature sensitivity of mean growing‐season (April–October) normalized difference vegetation index (NDVI) and ecosystem model simulations of gross primary productivity (GPP), and variability in mean growing‐season temperature for forest, shrub, and grass over NH. We find that higher interannual variability in mean growing‐season temperature leads to consistent decrease in interannual temperature sensitivity of mean growing‐season NDVI among all vegetation types but not in model simulations of GPP. Drier condition associates with ~130 ± 150% further decrease in interannual temperature sensitivity of mean growing‐season NDVI by temperature variability in forest and shrub. These results illustrate that varying temperature variability can significantly regulate the interannual temperature sensitivity of vegetation growth over NH, interacted with drought variability and nonlinear responses of photosynthesis to temperature. Our findings call for an improved characterization of the nonlinear effects of temperature variability on vegetation growth within global ecosystem models.