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Soil erosion changes after China's Grain‐for‐Green Program (GGP) have attracted widespread attention. Many studies have reported positive contributions of the GGP to sediment reduction; however, GGP effects on runoff remain under debate. The objective of this study was to identify runoff and sediment changes and estimate the contribution of human activities to soil erosion decreases in the Mang River basin (MRB) in the southeastern Loess Plateau. The temporal trends of the rainfall‐runoff‐sediment series between 1960 and 2017 and the contribution of human effects to runoff and sediment changes were determined using time‐series analysis methods. The main transformations in land‐use types were from farmland to forestland in the upstream MRB and farmland to built‐up land in the downstream MRB. Rainfall remained in a relatively steady state, while runoff and sediment had descending trends, both of which began to mutate in 1990 and 1994, respectively. The average runoff (sediment load) decreased by 33 × 104 m3 (5 × 104 t yr−1), of which the human effect contributed to 79% (93%) of the decreases. During the descending period, the human effects on runoff and sediment increased with time. Sediment experienced a much larger reduction effect than runoff because of increased forestland area, which can greatly reduce soil erosion, in the MRB upstream of our study site; however, runoff was increased in the MRB downstream of our study site because urbanization led to the expansion of impervious surfaces. Our results provide new lessons for assessing the reduction effects of the GGP on soil erosion in an urbanized basin. [ABSTRACT FROM AUTHOR]

Houttuynia cordata Thunb., called Yuxingcao in Chinese, is an important medicinal plant and vegetable consumed in the southern regions of China. This review aims to summarize studies on the phyto-physiological chemistry, cytology, molecular biology, and genomics of H. cordata. Studies on the physiology and biochemistry of H. cordata have grown over the past few decades. Phenotypic and agronomic traits, tissue culture, elemental analysis, photosynthetic studies, bioactive compound identification, and antioxidant research have been reported. Molecular biological studies, such as those of molecular markers, microRNAs, DNA variations, protein variations, and transcriptomes have also advanced. Recent studies have focused on the rDNA and chloroplast genome of this plant. This review could serve as a basis to perform the genetic breeding, genomic advance, and cultivation of this valuable diversified plant resource for medicinal applications and vegetable production. [ABSTRACT FROM AUTHOR]

Changes in land use impact the landscape pattern and habitat quality (LPHQ) of ecosystems. Since 1999, the Grain‐for‐Green Program (GGP) has brought dramatic changes in land use in Western China. Although many studies have reported positive contributions of the GGP to sediment reduction, the effects of the GGP on LPHQ remain unclear. This study aimed to assess the spatiotemporal characteristics of LPHQ in the Xiaolangdi Reservoir Area in China (XRAC) before and after GGP implementation (in 1990, 2000, 2010 and 2020) using the InVEST habitat quality model. The results showed that: (1) From 1990 to 2020, the main land use changes in the XRAC were a 34.97% increase in forestland and a 37.56% decrease in farmland. The landscape pattern showed decreased fragmentation and tended toward aggregation, and forestland became the dominant land use type. (2) Habitat quality in the XRAC improved from 0.63 to 0.91 between 1990 and 2020. High‐quality habitat (0.80–1) was observed in 88.24% of the XRAC in 2020. The spatial distribution of habitat degradation decreased overall, with some localized increases; areas with high levels of habitat degradation shrank and aggregated with the concentration of human activities. (3) The spatiotemporal evolution of habitat quality was influenced by both natural factors and human activities; the short‐term improvement in habitat quality in the XRAC was significantly related to the increase in forestland area, decrease in farmland area, and increase in vegetation coverage. Our results provide evidence for assessing the ecological benefit of the GGP in the Yellow River basin. [ABSTRACT FROM AUTHOR]

Toona sinensis, a perennial and deciduous tree belonging to the Meliaceae family, has been cultivated for more than 2000 years in China. Storing the buds of T. sinensis is difficult, as it is easy for them to rot during storage, which seriously affects their edible and commodity value. Young leaves and buds of T. sinensis plants are excellent source of flavonoids, terpenoids, phenylpropanoids, and more. In addition, the bioactive components of T. sinensis possess numerous health benefits, such as antiviral, antioxidant, anti-cancer, anti-inflammatory, and hypoglycemic effects. In this review, we summarize the storage and preservation, nutritional components, specific chemical compounds, pharmacological value, function genes, and omics of T. sinensis. This review aims to provide basic knowledge for subsequent future research seeking to understand the comprehensive biology and use of T. sinensis as a favored Chinese food and pharmacological resource. [ABSTRACT FROM AUTHOR]

Ethyl carbamate (EC) is a genotoxic and carcinogenic compound that is also a by-product of fermented foods (bread, sour milk, soy cheese, etc.) and alcoholic beverages (wine, sake, distilled liquor, etc.). Studies have showed that ethyl carbamate is ingested by humans primarily through the consumption of alcoholic beverages. Many countries have thus established EC limits for alcoholic beverages. Chinese liquor (Baijiu) is a traditional and unique distilled liquor, which has a huge consumption in China due to its excellent color, flavor, and taste. Therefore, the control of EC in Chinese liquor is of great significance. This review summarized for the first time the progress in presence level, analysis method, formation mechanism, and elimination strategy of EC of Chinese liquor in recent decades. Key points: • GC-MS and HPLC are the main methods to quantify EC in Chinese liquor. • EC is formed in the fermentation, distillation, and storage stage. • EC content can be reduced from raw material, microorganism, and production process. [ABSTRACT FROM AUTHOR]

Light use efficiency (LUE) is one of the important parameters on calculating terrestrial gross primary productivity (GPP) and net primary productivity (NPP). Based on 5-year (2006-2010) carbon flux and climatic variable data of a mixed plantation in north China, the seasonal and interannual variation of LUE was investigated and the biophysical controls were examined. Our results show that LUE had a distinct seasonal course, and peaked in the vigorous growing season with a value of 0.92-1.27 g C MJ. During the period of 2006-2010, annual mean LUE ranged between 0.54 and 0.62 g C MJ, and it was linearly correlated with annual GPP. In the growing season, LUE was significantly linked with the water availability variables (including monthly mean vapor pressure deficit (VPD), precipitation, evaporative fraction (EF), and the ratio of precipitation to evapotranspiration (P/ET)) and canopy conductance ( g ). However, EF was a better estimator of LUE compared with other biophysical variables. LUE decreased with an increase of the clearness index ( CI), indicating that LUE was higher under cloudy sky conditions than that under sunny sky conditions in the mixed plantation. [ABSTRACT FROM AUTHOR]

• iWUE of the young stand was higher than that of the old stand. • Trees at the more precipitation site had the stronger resistance to drought. • SPEI had a significant effect on iWUE at the young stand. As one of the main afforestation species, Pinus tabulaeformis is an important carbon sink in China. We developed tree-ring chronologies of Pinus tabulaeformis at five plantation sites (Lingkong Mountain (LKM), Fujia (FJ), Heishui (HS), Caijiachuan (CJC) and Jiufeng (JF)), and measured the δ13C values of tree rings using the stable carbon isotope method to calculate intrinsic water use efficiency (iWUE). The responses of net primary productivity (NPP) and iWUE to climatic variables were explored. The annual variation in both NPP and iWUE had increasing trends, with lower iWUE increasing rate at LKM site in comparison with those at other 4 sites. iWUE of the young stand was higher than that of the old stand. Annual patterns of the δ13C values showed significant decreasing trends in LKM and CJC but a rising trend in HS. The growth of Pinus tabulaeformis was more sensitive to temperatures, and temperatures exerted positive effects on NPP and iWUE. At the old stands, both NPP and iWUE had closer relationships with temperatures. On the annual scale, precipitation had little effect on NPP and iWUE. Annual mean standardized precipitation evaporation index had a significant influence on iWUE at the young stand. Resistance was positively correlated with recovery, resilience and iWUE, but negatively correlated with NPP. Pinus tabulaeformis at CJC site had the stronger resistance to drought events in comparison with that at LKM and FJ sites. This study provides insight into the responses of Pinus tabulaeformis productivity and water use to climate change, and helps evaluate carbon sink and water-carbon trade-off of plantations. [ABSTRACT FROM AUTHOR]

Aim Sarcopenia and sarcopenic obesity are significant associative factors for functional impairment related to aging. The main aim of the present study was to investigate the prevalence of sarcopenia and sarcopenic obesity, and their associations with functional status among men aged 80 years and older in Beijing. Methods A total of 75 young healthy volunteers, and 101 older men aged 80 years and older participated in the present study. Demographic characteristics, anthropometry, skeletal muscle mass measured by dual X-ray absorptiometry ( DXA), 6-m gait speed and handgrip strength were collected. Relative appendicular skeletal muscle index ( RASM) and percentage skeletal muscle index ( SMI) were obtained. Results Overall, the prevalence of sarcopenia was 45.7% by using RASM. By the weight-adjusted skeletal muscle index definition ( SMI), the prevalence of sarcopenia was 53.2%. The prevalence of sarcopenic obesity was lower by using RASM than SMI (4.9% vs 11.5%, P < 0.05). When we compared the sarcopenia prevalence (%) in obese participants, it was also remarkably lower by using RASM (40.0%) than SMI (95.0%). By using either RASM or SMI, gait speed was of no significant difference among the pure sarcopenia group, pure obese group and sarcopenic obesity group (0.76 ± 0.27 vs 0.82 ± 0.37 vs 0.82 ± 0.27 m/s, P > 0.05, by RASM; 0.75 ± 0.25 vs 0.92 ± 0.27 vs 0.82 ± 0.35 m/s, P > 0.05 by SMI), respectively. Multiple linear regression analyses showed that thigh skeletal muscle mass was positively correlated with gait speed independently (β = 0.221, P = 0.011), and total body fat (β = −0.216, P = 0.002) and age (β = −0.524, P = 0.000) were negatively correlated with gait speed independently. Conclusions The prevalence of sarcopenia is high either based on RASM or SMI among Chinese men aged 80 years and older. Functional limitations were significantly associated with older age, skeletal muscle mass and total body fat. Geriatr Gerontol Int 2014; 14 (Suppl. 1): 29-35. [ABSTRACT FROM AUTHOR]

Highlights: [•] Calculating and validating Q. variabilis transpiration δ T under NSS conditions. [•] δ ET of ecosystem obtained by Keeling curve showed an n-shaped variation in sunny day. [•] Transpiration also accounted for majority of ET under NSS conditions in the hilly area. [•] Vapor concentration was the key factor in partitioning evapotranspiration with isotope method. [•] Foreign vapor caused more uncertainties in the isotopic ET partitioning. [ABSTRACT FROM AUTHOR]

Abstract: In recent decades, forest area in China increased rapidly by afforestation and reforestation, especially in its temperate parts. However, lack of information on carbon exchange in temperate plantations in China reduced the accuracy of estimation on regional carbon budget. In this study, CO2 flux was measured using the eddy covariance method over a broadleaf dominant mixed plantation in the lithoid hilly area of the North China. The results showed that annual maximum photosynthetic capacity (A max) varied from 0.81 to 1.22 mg CO2 m−2 s−1 and annual initial light use efficiency (α) from 0.014 to 0.026. Net CO2 uptake was depressed when vapor pressure deficit (VPD) was more than 2.5 kPa. Annual temperature sensitivity coefficient (Q 10) for ecosystem respiration, ranged from 1.84 to 2.35, was negatively correlated with base ecosystem respiration (R 0) (P < 0.05). Annual R 0 decreased but Q 10 increased evidently when winter drought occurred. From 2006 to 2010, annual net ecosystem carbon exchange (NEE), Gross primary productivity (GPP) and ecosystem respiration (R ec) were −355 ± 34, 1196 ± 21 and 841 ± 43 g C m−2 yr−1, respectively. The warm-temperate mixed plantation in the lithoid hilly area of the North China was a strong carbon sink of the atmosphere, which was usually weaken when spring drought happened. [Copyright &y& Elsevier]

Negative air ion (NAI) plays a vital role in promoting the psychological and physiological functions of the human body and is an essential indicator for measuring the air cleanliness of a given area. In this paper, we presented and compared the results of two methods for identifying the main environmental factors affecting changes of NAI in a warm-temperate region of China. NAI concentration was estimated based on measured data during the main growing season in a warm-temperate forest and was used as the dependent variable in the traditional multiple linear regression and random forest models. Air pollutants and certain weather, radiation, and soil factors were selected as predictors based on their potential influence on NAI. Two methods were applied for the analysis, and the latter was a non-parametric alternative based on an ensemble of classification and regression trees. We compared the precision of the two models, and the variables of each method on the basis of their levels of importance; Independent samples was used in model validation, then we discussed the important environmental factors affecting changes of NAI concentration for both linear and nonlinear perspectives, along with the potential implications of environmental factors on NAI. The random forest model showed a higher accuracy comparison with the multiple linear regression model. Furthermore, the analysis also indicated its better performance by using independent test data for 10-fold cross-validation of the random forest model, and showing that this method has potential for broad-scale application in the assessment of environmental-factor influence on NAI. Certain selected variables that were common to both models (particulate matter 2.5, soil moisture, and relative humidity) appeared to influence NAI to a relatively large extent, demonstrating the decidedly influential role of these parameters on NAI concentration. • Two models are tested to optimize application in NAI–environmental factor influence. • Particulate matter, soil moisture, and relative humidity strongly influence NAI. • Random forest has high predictive ability and better model performance. [ABSTRACT FROM AUTHOR]

• Nitrogen fixation by leguminous Robinia pseudoacacia was not obvious. • Soil organic carbons stocks in the 16- and 49-year-old plantations were similar. • Soil organic carbon was negatively correlated with soil pH. • Robinia pseudoacacia plantations showed soil acidification across entire profiles. Over the past several decades, a vegetation restoration project has been conducted in the southeastern Loess Plateau of China by converting cropland into forest plantations to combat soil erosion. However, the effects of land use change on soil fertility are poorly documented. Here, we assessed soil chemical properties in areas of the southeastern Loess Plateau following afforestation of cropland with Robinia pseudoacacia plantations that had been established for 16 years and 49 years, a 49-year-old naturally restored forest, and adjacent cropland. We found that the effect of afforestation on soil organic carbon and total nitrogen mainly occurred at shallow depths. Soil organic carbon and total nitrogen concentrations in the topsoil of both 49-year-old forests were significantly higher than those in cropland. However, the highest total phosphorus concentrations were observed in the topsoil of cropland due to the application of fertilizer. The nitrogen-fixing effect of leguminous Robinia pseudoacacia was not obvious through comparisons of soil total nitrogen within 49-year-old naturally restored and planted forests. Our results indicate that both natural restoration and planting can increase soil organic carbon stocks, but that the increase after 16 years is slight. In this experiment, we found that soil organic carbon concentrations were negatively correlated with soil pH for all four land use patterns, and that the strength of the correlation increased with time since restoration. In contrast to cropland and naturally restored forest, plantations of both ages showed soil acidification across their entire profiles. This may be due to the root exudate and rhizosphere environment created by R. pseudoacacia. These results provide important insights about the impacts of ecological restoration on soil chemical properties in the Loess Plateau and elsewhere. [ABSTRACT FROM AUTHOR]

Both exotic and native plant invasions can have profound impacts on ecosystems. While many studies have examined the effects of exotic plant invasions on soil properties, relatively few have tested the effects of native plant invasions on soil microbial communities. Furthermore, we know little about the effects of native plant invasions on microbial communities in litter. In subtropical forests in southern China, we sampled litter at three decomposition stages and top soil in three forest sands representing three stages of the invasion (not invaded, moderately and heavily invaded) by the Moso bamboo (Phyllostachys edulis (Carriere) J. Houzeau), a native species in China. We measured chemical properties (concentrations of C, N, P, Mg, Al, K, Ca, Mn, Cu, and Zn, and concentrations of cellulose and lignin) and microbial communities in litter and/or soil. The bamboo invasion, in general, decreased the element concentrations in litter and soil and also decreased total microbial abundance and diversity. Considering bacteria and fungi separately, the bamboo invasion decreased fungal diversity in litter and soil, but had little impact on bacterial diversity, suggesting that fungi are more sensitive and vulnerable to the bamboo invasion than bacteria. We conclude that native Moso bamboo invasions into subtropical forests may lead to a complex biogeochemical process in the litter–soil system, which may threaten local forest ecosystems by affecting microbial communities and, thus, litter decomposition and nutrient cycling. [ABSTRACT FROM AUTHOR]

• WUE increased by 4.45–21.49% under cloudy conditions compared with clear conditions. • DF interacted with VPD, PAR and g c to regulate WUE at evergreen coniferous forests. • The regulation of DF on WUE was less in the dry year than that in normal year. Ecosystem water use efficiency (WUE) is an indicator characterizing carbon-water coupling of the terrestrial ecosystems. The increasing diffuse radiation enhances carbon assimilation. However, the impact of diffuse radiation interacting with biophysical factors on WUE is still not well-understood. Based on carbon and water vapor fluxes measured by the eddy covariance systems during 2019–2020, we explored the effects of biophysical factors on WUE under different sky conditions at 6 plantation ecosystems (2 deciduous broad-leaved and 4 coniferous plantations) in eastern China. WUE on cloudy days was 4.5–21.5% higher than that on clear days at 6 sites, which was attributed to the increase in ecosystem carbon gain and reduction in water loss. Diffuse fraction (DF) exerted significantly positive direct effects on WUE at JZ, MQ, JY and SHB sites (p < 0.05), with the path coefficients of 0.30–0.58. However, it had positive indirect effects on WUE at HS 1 and HS 2 sites by altering photosynthetically active radiation (PAR), vapor pressure deficit (VPD) and canopy conductance (g c). WUE was primarily regulated by VPD and g c , and the path coefficients of the direct effect were -0.34−-0.73 and -0.33−-0.73, respectively. The indirect effect of VPD on WUE through stomatal behavior was remarkable. Compared with the normal year, the regulation of DF on WUE was less in the dry year. For subtropical evergreen coniferous and warm-temperate deciduous broad-leaved plantations, WUE of the dry year was higher than that of the normal year. Warm-temperate deciduous broad-leaved plantations avoided drought by reducing g c to remain conservative water-use strategy, whereas the subtropical evergreen coniferous plantation kept high g c to obtain lower WUE in the dry year. These findings will contribute to understand the influence of diffuse radiation on the coupling between carbon and water vapor fluxes. [ABSTRACT FROM AUTHOR]

Highlights: [•] The seasonal and interannual variations of ecosystem WUE were analyzed. [•] The impacts of climate variables on WUE were discussed. [•] Cloudiness can improve photosynthesis and enhance WUE. [•] The major driver of interannual variability in WUE was soil water content in May. [Copyright &y& Elsevier]

To mitigate severe environmental problems, the Chinese government introduced many ecological projects in degraded regions in the past 20 years. At the same time, ecological projects occupied cultivated croplands and thus, the income of local residents was significantly affected. From the perspective of both economic and ecological benefits, converting the current land use system into agroforestry systems is suggested in this study. Through a scientific design, an agroforestry system will be capable of supplying considerable output to residents in the land conversion region. In addition, the government should create an appropriate subsidy system, stable market environment, and free agricultural training services to help farmers. Amidst the increasing population and limiting cropland expansion globally, agroforestry is an answer to problems related to achieving the aims of sustainable development in China and other developing countries. [ABSTRACT FROM AUTHOR]

Both sensible and latent heat fluxes are important components in the land surface energy budget, and accurately estimating them on kilometer-scale are important for understanding and modeling local hydro meteorological process. Scintillometry could provide kilometer-scale averaged turbulent heat fluxes, and has been used as ground-based remote sensing for estimating surface energy and water budget. This research compared heat fluxes obtained using an optical-microwave scintillometer (OMS) and an eddy covariance system (EC) over a typical temperate deciduous forest in hilly area, northern China. The observation period mainly represents growing season, from April to October 2018. We estimated the sensible and latent heat fluxes using both the two-wavelength method and the bichromatic correlation method, and the EC measurements were used as a benchmark. The results show the sensible heat fluxes from OMS showed 2% higher than EC, whilst the latent heat fluxes from OMS showed around 10% higher than EC. Changes in hydrological conditions or footprints have no significant effects on the measured turbulent fluxes from OMS. We also founded that there are slightly differences between fluxes derived by the two-wavelength method and the bichromatic correlation method due to assumed r Tq value. Based on these results, we conclude that OMS can be a reliable approach to measure kilometer-scale surface turbulent heat fluxes over the hilly area, and its ability to estimate kilometer-area sensible and latent heat fluxes looks promising. • This is a unique dataset of the two-wavelength method in calculated latent and sensible heat fluxes, which are lacking in the literature. • The microwave scintillometer (RPG-MWSC-160, Radiometer Physics GmbH, Germany) is a new commercialized microwave scintillometer device, and there is rare literature on its performance over a typical temperate deciduous forest in hilly area. • The result can provides much needed information about the performance of the OMS system and, more generally, two-wavelength scintillometry. [ABSTRACT FROM AUTHOR]

Diffuse solar radiation plays important role in carbon exchange between forest ecosystems and the atmosphere. Based on a 2-year (2016–2017) dataset of global and diffuse solar radiation, the annual mean diffuse fraction (the proportion of diffuse solar radiation to global solar radiation, DF) was approximately 0.45 over the plantation canopy. A proposed model (BRL-1), including six predictors (half-hourly clearness index CI, solar elevation angle, apparent solar time, daily CI, a persistence of global solar radiation and relative humidity), was developed using the ground-based measurements data of 2016. The DF values estimated by the proposed model were in good agreement with the measured ones. The values of the coefficient of determination (R2), the root mean squared error (RMSE), the mean bias error (MBE) and the t stat for the proposed model were 0.82, 0.12, 0.002 and 1.16, respectively, lower than the results derived from other models. Therefore, the performance of the proposed model estimating half-hourly DF was better than the other models. Moreover, half-hourly diffuse solar radiation in cloudy skies estimated by the proposed model was more consistent with the measured one than that under clear skies. This study aims at helping us understand the change of diffuse solar radiation with clouds. Relationship between clearness index (CI) and solar elevation angle (β). Scatter plots of diffuse fraction (DF) and CI, half-hourly measured diffuse solar radiation and estimated values. Image 10927 • Diffuse fraction was correlated with relative humidity and clearness index. • The performance of the proposed model was better than other eight models. • Estimated diffuse radiation was consistent with measured values in cloudy skies. [ABSTRACT FROM AUTHOR]

The Three-North Shelter Forest (TNSF) is an important ecological barrier in northern China. However, in the last decade, poplar tree degradation has occurred in ∼80% of TNSF stands in Zhangbei County (Hebei Province), with about one-third of trees either dead or dying. Using isotopic techniques, we investigated the corrected δ 13 C value of tree-ring ( δ 13 C cor ) and intrinsic water-use efficiency (iWUE) differences between non-dieback and dieback trees of the same age to understand the cause of poplar dieback death associated with the TNSF. We found that the diameter of poplar trees within the same age group decreased as degradation progressed. From 1997, inter-group differences of δ 13 C cor and iWUE occurred but were not statistically significant. The differences became significant from 2002. Comparisons suggest that the continuous occurrence of positive ΔiWUE (iWUE dieback −iWUE non-dieback ) may be the threshold for subsequent divergence of the two groups. Stepwise regression revealed that the impact of groundwater depth on iWUE was stronger than that of other environmental factors (e.g., temperature and evapotranspiration) and was the leading cause of poplar degradation. IsoSource model analyses indicated that non-dieback trees took water mainly from soil 30–80 cm below the ground surface, and that dieback trees did it mainly from 0–30 cm below the surface. Non-dieback trees used more water from the 80–150 cm soil layer and groundwater than did dieback trees. Groundwater depth, which increased in the experimental area and so aggravated local droughts, was strongly related to cumulative water consumption but not to evapotranspiration (ET 0 ), indicating that increasing groundwater depth was primarily caused by the change in land use. Therefore, poplar dieback in the TNSF in Zhangbei County was attributed to groundwater overuse associated with changed land use, which enhanced the duration and intensity of water stress on the trees. [ABSTRACT FROM AUTHOR]

• Divide 192 months into 4 groups by PCA and CA based on 4 meteorological factors. • Any individual meteorological factor is far from adequate to determine C fluxes. • Effective accumulated temperature plays a vital role in regulating C fluxes. • Precipitation is the limiting factor in the transitional phase of growing period. • Short-term seasonal drought has significant negative impacts on C fluxes. Influences of meteorological factors on the carbon fluxes of a forest ecosystem can vary with time scales. While many studies were made on daily to annual variations of measured carbon flux of forest ecosystems, few were conducted on the variations of observed carbon fluxes over longer (decadal or more) time scale. This study quantified the influences of meteorological variables on the measured carbon fluxes in a Quercus variabilis plantation from 2006 to 2021 using principal component analysis (PCA) and cluster analysis (CA). PCA was used to identify the most important meteorological variables. They are monthly mean daily maximum global radiation (Rg), monthly effective accumulated temperature (Tac), monthly mean daily maximum vapor pressure deficit (VPD), and monthly precipitation (PP). CA was used to group 192 observed months into four groups based on those four meteorological variables and their effects on the observed carbon fluxes. Structural equation modeling (SEM) was then used to quantify the relative importance and direct or indirect effects of those four meteorological factors on carbon fluxes at the interannual timescale in each of the four groups. The results showed that air temperature had dominant influence on net ecosystem productivity (NEP) and ecosystem respiration (Re) with its relative importance measured by standardized coefficients (SC) of 0.59 and 0.97, respectively. PP directly impacted gross primary production (GPP) with an SC of 0.40 and indirectly influenced NEP and Re. The importance of a given meteorological factor on carbon fluxes and the dominant meteorological factors varied among the four groups. Tac mainly influenced Re with a SC of 0.79 in Group 1 (the nongrowing season). The direct effects of PP on NEP and GPP and indirect effects on Re were most prominent in Group 2 (the transition stage between the nongrowing season and the growing season). Tac and PP had greater influences than other two variables in Group 3 (the transitional stage of early growth and vigorous growth and the transitional stage of steady growth and dormant period). NEP increased with Tac, while excessive rainy weather accompanied by a decrease in temperature and radiation reduced Re and GPP in Group 4 (the wet season). The short-term seasonal droughts with warm air temperatures but little precipitation (mainly in June) led to significant reductions in both GPP and NEP of the Quercus variabilis plantation ecosystem in the warm-temperate continental monsoon climate zone. Our results can be used to guide managing forest plantations in temperate region in China to maximize their carbon sequestration. [ABSTRACT FROM AUTHOR]

• Trunk-growth NEP EC and tree biomass growth are strongly correlated over 13 years. • EWδ13C and LWδ13C of different diameter classes trees are analyzed. • EW-PLWδ13C tracks the relationship between tree biomass growth and NEP EC. • Colder early growing season significantly enhances the correlation of EW-PLWδ13C. Eddy covariance (EC) and biometric (based on tree diameter and tree ring measurements) methods are used extensively to estimate annual variability in forest productivity. Many previous studies obtained inconsistent findings between net ecosystem productivity (NEP) based on EC (NEP EC) and tree biomass growth based on biometric methods, partly because of delayed responses in trees due to temporary non-structural carbohydrate (NSC) storage. Direct measurement of the amount of NSCs stored in trees is challenging; however, using carbon (C) isotope ratios in different tree components is considered an indirect and effective alternative approach for assessing NSC dynamics. We measured stable C isotope ratios in earlywood (EW) and latewood (LW) of rings of 70 trees (categorized as 4–10, 10–20, and > 20 cm diameter at breast height [DBH]) to test relationships between trunk-growth NEP EC time series and annual tree biomass growth (based on tree ring width) in a young mixed forest in northern China over 13 years. Our results revealed a strong correlation (r = 0.691) between trunk-growth NEP EC (March–August in a calendar year) and tree biomass growth. The change in correlation between current-year EW δ13C and LW δ13C of the previous year observed in trees with 10–20 cm DBH, which accounted for 51.8% of the total tree biomass growth, was consistent with the synchronicity of trunk-growth NEP EC and tree biomass growth. Colder early growing seasons, which significantly increase the reliance of early-season structural growth on stored labile C accumulated in the previous year, may lead to postponed tree biomass growth responses related to NEP EC. In conclusion, this approach, investigating C isotope analysis in EW and LW, helps elucidate the relationships between tree biomass growth and stand-level C fluxes in forest sites. [ABSTRACT FROM AUTHOR]

• NIRv and SIF were more effective at estimating phenological information than NDVI and EVI. • SOS and EOS played important roles in determining seasonal variabilities of GPP. • The variation of annual GPP could be captured by GSL GPP × GPP max , GSL NIRv × NIRv max , and GSL SIF × SIF max effectively. Phenology plays an important role in affecting carbon sequestration in terrestrial ecosystems in the context of climate change. Remote sensing techniques have been widely used to investigate land surface phenology and the effects of phenology on ecosystem production at regional and global scales. Recently, the near-infrared reflectance of vegetation (NIRv) and solar-induced chlorophyll fluorescence (SIF) have been shown to be more promising metrics of gross primary production (GPP) than the normalized difference vegetation index (NDVI) and the enhanced vegetation index (EVI). However, there is a lack of comparison in the performance of these techniques for deriving phenological metrics. In this study, we explored the consistency in phenological metrics derived from both remote sensing approaches (NDVI, EVI, NIRv, and SIF) and flux tower GPP at six plantations (two broadleaf forests (BF) and four coniferous forests (CF)) in eastern China over the period 2006–2020. The vegetation indices (NDVI, EVI, NIRv) were derived from MODIS data, and SIF was based on the global, OCO-2 based SIF product (GOSIF). We further evaluated the effects of spring and autumn phenology on GPP. The results showed that the flux tower GPP was effectively tracked by NDVI, EVI, NIRv, and SIF (P < 0.001). Meanwhile, the phenological metrics derived from EVI, NIRv, and SIF, including the start of growing season (SOS), the end of growing season (EOS), and the length of growing season (GSL), had significant relationships with those derived from GPP at the six plantations (P < 0.05). NIRv and SIF were more effective at estimating phenological information than NDVI and EVI. In addition, the root mean squared deviation (RMSD) values between the GPP- and NIRv-retrieved phenological dates were less than those derived from NDVI, EVI, and SIF at the BF sites. However, the differences among RMSD values of NDVI, EVI, NIRv, and SIF were not significant at the CF sites. The linear regression analysis showed that the advance of SOS GPP (i.e., SOS derived from GPP) significantly increased GPP (R2=0.29, P < 0.05) over the period from March to April, and the delay of EOS GPP (i.e., EOS derived from GPP) remarkably enhanced GPP (R2=0.61, P < 0.001) over the period from September to October at the BF sites. The relationship of EOS GPP with GPP (R2=0.90, P < 0.05) over the period September-October was strong at the CF sites. In addition, the variations of annual GPP could be captured by GSL GPP × GPP max , GSL NIRv × NIRv max , and GSL SIF × SIF max effectively across the BF and CF sites. These findings can help us understand the potential ability of NIRv and SIF in estimating phenological metrics and in revealing the effects of vegetation phenology on the carbon cycle. [ABSTRACT FROM AUTHOR]

The impact of extreme weather events on carbon fluxes and water-use efficiency (WUE) in revegetated areas under water-limited conditions is poorly understood. We analyzed changes in carbon fluxes and WUE over three years of eddy-covariance measurements in a Pinus tabuliformis plantation in Northeast China to investigate carbon fluxes and WUE responses to drought events at different time scales. Mean annual net ecosystem exchange (NEE), gross primary production (GPP), and ecosystem respiration (Re) were -368.48, 1042.42, and 673.94 g C m -2 , respectively. Drought events increased NEE, as GPP was more sensitive to water stress than Re at different growing stages. Mean annual WUE was 2.46 g C kg -1 H 2 O, and plant phenology played a key role in WUE responses to drought. Water stress had negative and positive effects on daily WUE at the early and late growing stages, respectively, and daily WUE was generally insensitive to drought at the mid growing stage. A lagged effect existed in the carbon fluxes and WUE dynamics after drought events at various time scales. Water stress at the early growing stage was more important than that at other growing stages on annual carbon sequestration and WUE, as it dominated canopy growth in the current year. The annual mean normalized difference vegetation index controlled interannual variations in carbon fluxes and WUE in the plantation. Our findings contribute to the prediction of possible changes in carbon and water fluxes under climate warming in the afforested areas of Northeast China., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)

In recent years, PM 2.5 pollution has become a most important source of air pollution. Prolonged exposure to high PM 2.5 concentrations can give rise to severe health issues. Negative air ion (NAI) is an important indicator for measuring air quality, which is collectively known as the 'air vitamin'. However, the intricate and fluctuating meteorological conditions and vegetation types result in numerous uncertainties in the correlation between PM 2.5 and NAI. In this study, we collected data on NAI, PM 2.5 , and meteorological elements through positioning observation during the period of June to September in 2019 and 2020 under the condition of relatively constant leaf area in Quercus variabilis forest, a typical forest in warm temperate zones. We investigated the spatiotemporal variation of PM 2.5 and NAI under consistent meteorological conditions, established the correlation between PM 2.5 and NAI, and explicated the impact mechanism of PM 2.5 on NAI in natural conditions. The results showed that NAI decreased exponentially with the increases in natural PM 2.5 , with a significant negative correlation ( y =1148.79 x -0.123 ). The decrease rates of NAI in PM 2.5 concentrations of 0-20, 20-40, 40-80, 80-100 and 100-120 μg·m -3 were 40.1%, 36.2%, 9.4%, 2.4%, 5.1% and 6.8%, respectively. Results of the sensitivity analysis showed that the PM 2.5 concentration range of 0-40 μg·m -3 was the sensitive range that affected NAI. Our findings could provide a scientific basis for better understanding the response mechanisms of NAI to environmental factors.

Plantations have great potential for carbon sequestration and play a vital role in the water cycle. However, it is challenging to accurately estimate the carbon and water fluxes of plantations, and the impact of biophysical drivers on the coupling of carbon and water fluxes is not well understood. Thus, we modified the phenology module of the Biome-BGC model and optimized the parameters with the aim of simulating the gross primary productivity (GPP), evapotranspiration (ET) and water use efficiency (WUE) of a warm-temperate plantation in northern China from 2009 to 2020. Photosynthetically active radiation (PAR) showed significant positive correlations on GPP and WUE during the first stage of the growing season (S1: from early April to late July). Active accumulated temperature (T aa ) mainly controlled the changes in GPP and ET during the second stage (S2: between the end of July and early November). Throughout the growing season, soil water content dominated daily GPP and WUE, whereas T aa regulated ET. The optimized Biome-BGC model performed better than the original model in simulating GPP and ET. Compared with the values simulated by the original model, root mean square error decreased by 7.89 % and 15.97 % for the simulated GPP and ET, respectively, while the determination coefficient increased from 0.77 to 0.81 for simulated GPP and from 0.51 to 0.62 for simulated ET. The results of this study demonstrated that the optimized model more accurately assessed carbon sequestration and water consumption in plantations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Taking the coniferous and broad-leaved mixed forest of Tianmu Mountain National Nature Reserve in Zhejiang Province as research object, we divided the tree species into three pairs, including evergreen and deci-duous species, broad-leaved and coniferous species, dominant and non-dominant species, to compare the difference of the individual tree carbon stock of each pair and analyze the diameter distribution pattern and tree height distribution pattern of carbon stocks. The relationship between spatial structure and individual tree carbon stock was analyzed by using spatial structure indicators including V&#95;Hegyi competition index, complete mingling and aggregation index, to reveal the relationship between the structure of coniferous and broad-leaved forests and carbon stocks, and provide a theoretical basis for management of forest carbon sequestration. The results showed that the average individual carbon stock for evergreen and deciduous species, broad-leaved and coniferous species, dominant and non-dominant species were 57.7 and 87.4 kg, 54.6 and 74.7 kg, 67.4 and 48.1 kg, respectively. The individual tree carbon stock of evergreen species was significantly lower than that of deciduous species, the individual tree carbon stock of broad-leaved species was significantly lower than that of coniferous species, and the individual tree carbon stock of dominant tree species was significantly higher than that of non-dominant tree species. The diameter distribution and height distribution of carbon stock of each species group obeyed normal distribution. The V&#95;Hegyi competition index was significantly negatively correlated with individual tree carbon stock, and it was consistent with the power function distribution. Both complete mingling and aggregation index were linearly and positively correlated with individual tree carbon stock. The direction of influence of different spatial structures on the individual tree carbon stock was consistent. The structure of coniferous and broad-leaved mixed forest had a significant impact on individual tree carbon stock. In the management of forest carbon sequestration and sink enhancement, it is necessary to regulate the unreasonable forest structure and promote its succession to the climax community in order to improve forest carbon stock.

Leaf phenology is one of the most reliable indicators of global warming in temperate regions because it is highly sensitive to temperatures. Temperature sensitivity (S T ) is defined as the values of changed days of leaf flushing date (LUD) per degree increase in temperatures. Climate warming substantially advanced LUD in the temperate region, but its effect on S T of LUD is still not clear. We used spring phenological records of 12 woody plants in eastern China in the years of 1983-2014 to explore temporal and spatial changes of LUD and S T . Furthermore, we compared the difference of S T and preseason temperatures in two periods (1983-1997 and 2000-2014), and explored the main factors regulating S T . The results showed that the average LUD significantly advanced (-2.7 days per decade). The mean LUD over the period 1983-2014 was in day of the year (DOY) 87 ± 7 across sites and species for the early leaf flushing species (EFS), and mean DOY 102 ± 5 for the late leaf flushing species (LFS). LUD was earlier in low latitude than that in high latitude. S T of Armeniaca vulgaris was the most sensitive to temperature across all sites (-3.66 d °C -1 ), while Firmiana simplex was the most insensitive (-2.37 d °C -1 ). LUD of EFS was more sensitive to temperature warming than that of LFS. At the same site, LUD of EFS would advance more obviously than that of LFS under global warming. For all species, S T decreased significantly with shorter preseason length and warmer temperatures at the preseason end. Our results had demonstrated a strong relationship between S T and the preseason length (mean temperature at the preseason end)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Southern Taihang Mountain area is an important part of the key ecological regions along the Yellow River in China. Understanding the climate change trend in this area is of significance for the maintenance of ecological security and the planning and decision-making of major ecological projects in the Yellow River Basin. Taking Jiyuan City in southern Taihang Mountain area as the research area, we analyzed the climate change trend in Jiyuan based on the meteorological data from 1980 to 2019. The results showed that climate in Jiyuan tended to be warmer and wetter during the study period. The change rates of temperature and precipitation were 0.48 ℃·(10 a) -1 and 14.21 mm·(10 a) -1 , respectively. The rise of temperature in spring and summer was higher than that in autumn and winter. Climate was warmer and drier in spring, while warmer and wetter in the other three seasons. Potential evapotranspiration and aridity index showed increasing and decreasing trends, with the average value of 748 mm and 1.36, respectively. The first and last days ≥10 ℃ were about 3 days in advance and 1 day in delay every 10 years. The change rate of effective accumulated temperature ≥10 ℃, duration days ≥10 ℃ and high temperature days were 116.57 ℃·(10 a) -1 , 4 d·(10 a) -1 , and 5 d·(10 a) -1 , respectively. The 1990s was the driest decade in Jiyuan during the study period, with strongest increases of temperature. Half of the years showed the characteristics of semi-arid climate in that decade. From 2010 to 2019, the trend of climate warming and wetting in Jiyuan had accelerated significantly, which was the warmest and wettest decade. In recent 10 years, duration days ≥10 ℃ and the effective accumulated temperature increased by about 28 days and 389.36 ℃, respectively. The frequency and intensity of high temperature weather also increased significantly in this decade.

Background: A diversity of microorganisms is associated with human health and exists in a state of dynamic equilibrium. This diversity has direct implications for the assessment of susceptibility to infectious diseases, especially human papillomavirus (HPV) infection., Methods: Here, we investigated the relationships between HPV infection and vaginal, cervical, and gut microbiota composition and assessed the levels of genital immune mediators. We selected a multiethnic area in Yunnan Province, China, to collect samples from healthy women of childbearing age. A total of 82 healthy women of childbearing age were included in this study. Vaginal, cervical, and rectal swabs were collected to analyze the microbial community, and cytokines were analyzed in some samples., Findings: Different proportions and types of HPV infection were detected in cervical (44%), vaginal (18%), and rectal (18%) swabs. HPV detected in cervical swabs was generally a high-risk type, while low-risk HPV types were primarily detected in vaginal and rectal swabs. There were some differences in this proportion as well as in the microbial community composition among different ethnic groups. Rectal samples exhibited the highest diversity index, while vaginal samples displayed the lowest diversity index. Lactobacillus dominated most of the vaginal samples, was decreased in HPV-positive samples, and differed among different ethnic groups. However, the sequence proportion of Lactobacillus in the cervix exhibited the opposite trend in those affected by HPV infection. The dynamic balance between the potential pathogens Gardnerella and Lactobacillus determines the health of the female genital system., Interpretation: This study constitutes the first step toward personalized medicine for women's reproductive health, wherein differences between the genital microbiomes of individuals would be considered in risk assessment and for subsequent disease diagnosis and treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Liu, Xiao, Fang, Dong, Ye, He, Wang, Li, Zhao, Yuan, Zhao, He, Zhang, Yang, Wu and Li.)

Pinus sylvestris var. mongolica is one of the important tree species for afforestation in Three-North Regions of China. Investigating net ecosystem exchange (NEE) and its influencing factors is of significance in understanding carbon balance of P. sylvestris var. mongolica plantation . We used the eddy covariance system and its supporting instruments to measure NEE and environmental factors of P. sylvestris var. mongolica plantation in the western Liaoning Province in 2020. The results showed that, at the half-hour scale, plantation emitted carbon during nighttime and sequestrated carbon over daytime. Carbon sequestration was inhibited by drought stress in the afternoon from May to August. At the daily scale, seasonal dynamics of nighttime NEE were mainly controlled by soil temperature and moisture, while that of daytime NEE were mainly controlled by soil moisture and vapor pressure deficit due to drought stress. When soil was dry, precipitation promoted nighttime and daytime NEE and improved photosynthetic and respiration parameters. At the month scale, there was significant negative linear relationship of daytime NEE with ecosystem apparent quantum yield and ecosystem maximum photosynthetic capacity. When air temperature was lower than 5 ℃, ecosystem respiration rate at 10 ℃ and temperature sensitivity of ecosystem respiration increased linearly with decreasing air temperature. The cumulative NEE of P. sylvestris var. mongolica plantation was -145.17 g C·m -2 , indicating a weak carbon sink in 2020.

To explore the effects of diameter class on the climate-growth relationship of trees, the width chronologies of ringwood, earlywood, and latewood of Quercus variabilis were established in the low altitude area of the south aspect of the Taihang Mountains. We estimated the sensitivity of radial growth of two diameter classes of Q . variabilis plantation to climate. The effects of drought events on Q . variabilis plantation was quantified by superimposed time analysis. Under climate change, we aimed to provide reference data for sustainable management of Q . variabilis . Our results showed that the mean sensitivity of ringwood and latewood of large diameter classes were higher than small diameter classes. The mean sensitivities of earlywood of small diameter classes were higher than large diameter classes. The latewood was the most sensitive component of tree-ring. The responses of the standard chronological indices of two diameter classes to climate factors were similar. The growth of ringwood and latewood of small diameter classes were more sensitive to the climatic factors from June to August. The earlywood was more sensitive to the climatic factors before the growing season (from January to February). Furthermore, the earlywood of large diameter classes was more sensitive to the climatic factors of the last year, with a stronger hysteresis effect. It suggested that Q . variabilis was sensitive to drought. The radial growth of Q . variabilis of ringwood and latewood in drought year was significantly lower than that of last year. The reduction of Q . variabilis with large diameters was higher than that of small diameters, but with higher growth recovery degree after drought.

Background: Although the introduction of dapoxetine has ushered in a new era in the treatment of premature ejaculation, many patients with lifelong premature ejaculation (LPE) exhibit an unimproved clinical global impression even after treatment with dapoxetine., Aim: To investigate independent predictors of the improvement of Clinical Global Impression (iCGI) in patients with LPE treated with dapoxetine and develop a nomogram to predict a patient's likelihood of achieving iCGI., Methods: Data of 243 patients with LPE diagnosed at Xijing Hospital (Xi'an, China) and Northwest Women's and Children's Hospital (Xi'an, China) from January 2019 to May 2020 were analyzed. Independent predictors of iCGI were identified, and a nomogram was developed using R software based on a multivariate logistic regression model. The predictive accuracy of the nomogram was measured using the area under the receiver operating characteristic curve. The nomogram was calibrated by comparing predictions with observations., Main Outcome Measures: The primary outcome was the patient-rated Clinical Global Impression of Change scale score after a 4-week course of dapoxetine treatment, which was collected via an online questionnaire. A Clinical Global Impression of Change score of ≥1 was defined as iCGI in this study., Results: Patients with LPE with at least a bachelor's degree, a self-reported intravaginal ejaculation latency time of >1 minute, and an International Index of Erectile Function question 5 score of ≥3 were independent factors associated with achieving iCGI, whereas a Premature Ejaculation Diagnostic Tool question 1 score of ≥2 was an independent factor negatively associated with achieving iCGI. The predictive accuracy of the nomogram, which was developed by integrating all variables with independent predictive significance, was 0.710 (95% confidence interval: 0.702-0.718). In addition, the calibration plot demonstrated excellent agreement between predictions and observations., Clinical Implications: If the predictive performance of our nomogram is further proven in multiple external validations, it can be used to select suitable patients for dapoxetine treatment, thereby reducing the number of patients discontinuing treatment., Strengths & Limitations: This study developed the first nomogram for predicting the likelihood of achieving iCGI in patients with LPE treated with dapoxetine. However, our nomogram was not externally validated using independent cohorts from other institutions., Conclusion: This study identified several independent predictors of iCGI in patients with LPE treated with dapoxetine. An effective nomogram was developed to predict their likelihood of achieving iCGI. External validations using data of Western patients with LPE are required to test the broader applicability of this Chinese patient-based tool. Hou G, Gao M, Zhang L, et al. An Internally Validated Nomogram for Predicting the Likelihood of Improvement of Clinical Global Impression in Patients With Lifelong Premature Ejaculation Treated With Dapoxetine. J Sex Med 2020;17:2341-2350., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

CYP27A1, CYP2R1 and CYP27B1 hydroxylases are involved in the synthesis of 1, 25-hydroxyvitamin D 3 , which plays a role in the immune regulation and pathogenesis of hepatitis C virus (HCV) infection. The aim of the present study was to investigate the relationships between polymorphisms in vitamin D pathway genes and HCV infection outcomes in a Chinese population. Nine single-nucleotide polymorphisms (SNPs) of CYP27A1, CYP2R1 and CYP27B1 were genotyped in a high-risk Chinese population. The distributions of these SNPs were compared among groups with different outcomes of HCV infection, including 863 cases of persistent HCV infection, 524 cases of spontaneous clearance, and 1079 uninfected controls. The results showed that the CYP2R1 rs12794714-G, rs10741657-A, rs1562902-C, and rs10766197-G alleles were significantly associated with increased susceptibility to HCV infection (all P FDR  < 0.05, in additive/dominant models), and the combined effect of the four unfavorable alleles was related to an elevated risk of HCV infection in a locus-dosage manner (P trend  = 0.008). Moreover, haplotype analysis suggested that, compared with the most frequent haplotype (A rs12794714 G rs10741657 T rs1562902 A rs10766197) , the haplotype containing four unfavorable alleles, GACG, was associated with a higher risk of HCV infection. The results of our study suggest that genetic variants in CYP2R1 may be biomarkers for predicting the susceptibility to HCV infection in the Chinese population.

Vitamin D binding protein (VDBP) plays an important role in the immune modulation and pathogenesis of hepatitis C viral (HCV) infection by influencing serum vitamin D levels. The present study aims to evaluate the association of VDBP genetic polymorphisms with susceptibility to and chronicity of HCV infection in a high-risk Chinese population. Seven genetic variants in the VDBP gene were genotyped in a case-control study of 886 patients with HCV persistent infection, 539 subjects with spontaneous clearance, and 1081 uninfected controls. Logistic regression analysis was used to assess the effects of these variants on HCV infection outcomes. The results showed that two variants rs7041-G and rs3733359-T alleles were significantly associated with increased susceptibility of HCV infection, and the combined effect of the two unfavorable alleles was related to an elevated risk of HCV infection in a locus-dosage manner (P trend  = 8.16 × 10 -4 ). Interaction analysis manifested that rs7041-GT/GG and rs3733359-CT/TT jointly increased risk of HCV infection. Moreover, haplotype analysis suggested that compared with the most frequent TC haplotype, the haplotype carrying GT indicated a risk effect of HCV infection [odds ratio (OR) = 1.464]. However, no significant associations were observed for the other five variants. These findings implied that VDBP rs7041-G and rs3733359-T variants may contribute to increased susceptibility to HCV infection in a high-risk Chinese population., (Copyright © 2018 Elsevier B.V. All rights reserved.)

By using Circumference Dendrometer 2 (DC2), this paper studied the diurnal variation of trunk diameter in Quercus variabilis plantation at the south aspect of Taihang Mountains. During seasonal drought, the diurnal variation of Q. variabilis trunk diameter was quite evident. The time of the diameter shrinkage followed the start-up time of sap flow, but the appearance of the minimum trunk diameter lagged behind the maximum sap flow flux about 3-4 h. The maximum daily shrinkage (MDS) value of the trunk diameter presented a trend low-high-low, being significantly correlated with the diurnal differences of cumulative sap flow flux and leaf water potential and having a significant quadratic relationship with soil moisture content. The MDS value was affected by the variations of meteorological factors, being significantly correlated with the diurnal variations of air temperature, vapor pressure deficit, and relative humidity, but less correlated with the diurnal variation of solar radiation. After successive precipitation, soil moisture content was no longer the limiting factor of the diurnal variation of Q. variabilis trunk diameter. The MDS value had less correlations with the diurnal differences of cumulative sap flow flux, leaf water potential, soil moisture content, and other meteorological factors. Stepwise regression analysis indicated that the soil moisture content and air temperature in seasonal drought and rain seasons were the key factors affecting the diurnal variation of Q. variabilis trunk diameter.

Based on the canopy temperature and micrometeorological data of Quercus variabilis in its main growth season (from May to August) in hilly areas of North China in 2011, this paper analyzed the variations of canopy temperature (T(c)) in Q. variabilis plantation and their relations with micrometeorological factors in typically clear days and cloudy days. From 9:00 to 17:00 in clear days, the boundary layer of canopy was unstable, and the mean T(c) was 3.55 degrees C higher than the mean air temperature (T(a)). In cloudy days, the variations of T(c) were gentler than those in clear days. The T(c) was significantly correlated with T(a), net solar radiation (R(n)), relative humidity, and wind speed, with a multiple correlation coefficient being 0. 825. The T(a) and R(n) were the dominant meteorological factors controlling T(c), and their affecting degree on T(c) was associated with weather condition.

Transpiration is a major component of vegetation evapotranspiration, and a core in the study of plant water physiological ecology. Its measurement methods attracted extensive attention, among which, thermal dissipation is considered as an optimal method for measuring tree transpiration. Numerous studies showed that thermal dissipation method was relatively accurate in measuring individual tree transpiration and stand-scale water consumption. However, there exist potential errors between the true value and the measurements during measurement process. In this paper, the potential errors of thermal dissipation method in measuring sap flux density and of the temperature difference determination from single tree to stand-scale were reviewed, and the research prospects on the potential errors of thermal dissipation method in China were discussed. The corresponding solutions were also proposed.

Objective: To explore the cognitive psychological process of healthy children and children with cognitive disorder., Methods: Single Chinese character semantic priming and arithmetic tasks were delivered to 20 8-year-old healthy children, and 20 11-year-old healthy children, and 30 children with attention deficit hyperactivity disorder, 23 children with epilepsy, and 22 age-matched normal children as controls. Electroencephalography was used. Event-related potential was distilled by BESA software., Results: (1) During the Chinese character semantic priming, the amplitudes of N2 toward the non-related words and pseudo-words in the 8-year-old group were 12.1 microV and 11.7 microV respectively, both significantly larger than those of the 11-year-old group (3.7 microV and 4.8 microV, respectively, both P<0.05). The amplitudes of N2 and P2 toward the non-related words and pseudo-words among the children with attention deficit hyperactivity disorder were both significantly lower than those in the healthy children (both P<0.05). (2) During the arithmetic task, the latency values of P2 and P3 of addition, subtraction, and multiplication in the 8-year-old group of healthy children were all significantly longer than those of the 11-year-old group of healthy children (all P<0.05). The P3 latency of the children with epilepsy was significantly longer than that of the healthy children (P<0.05)., Conclusion: Chinese character and arithmetic cognitive waves are steady. ERP can be used to estimate the healthy children's personality index. Quantitative indicators are helpful in diagnosis and treatment of cognitive and learning disorders.

Objective: To investigate the correlation between the symptoms and serum levels of androgen in healthy Chinese men aged over 40 years, and to work out a new symptomatic inventory for screening late onset hypogonadism (LOH) in Chinese men., Methods: An 18-item questionnaire was designed and 637 respondents were collected from Beijing, Shanghai, Xi'an and Chongqing. Serum total testosterone, calculated free testosterone, testosterone secretion index and free testosterone index were measured. An analysis of the correlation between symptoms and androgens was performed., Results: The twelve-item symptoms were significantly correlated to 2 or more of the 4 androgens mentioned above, marking up a new symptomatic inventory for screening LOH, with a 70% sensitivity and 46% specificity., Conclusion: The new symptomatic inventory is acceptable for the screening purpose. The relatively low specificity may be related to the individual response to the decline of serum androgens and age-related changes of other hormones, such as GH-IGF-1 axis, DHEA, thyroid hormones, melatonin and leptin.