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Identity issues have been an area of focus in language learning motivation scholarship. However, the role of national identity in language learning motivation has not received sufficient attention. In response to the timely call for reflections on nationalism and language education, this study examines how political nationalism and cultural nationalism shape Chinese learners' motivation to learn Japanese. Our analysis suggests that cultural nationalism considerably enhances Chinese learners' motivation whereas the motivational impact of political nationalism is bifurcate. Our research helps illuminate the mechanism of the rooted L2 self and national interest in language learning motivation, especially in the Chinese context.

Anthropogenic emissions affect vegetation photosynthesis and carbon flux through meteorological variations induced by aerosols and clouds. However, the insufficient consideration of meteorological conditions limits the understanding of relevant mechanisms, and further inhibits the projection of future terrestrial carbon balance. Based on multiple sets of model simulations, we characterized changes in gross primary production (GPP) due to three typical individual pollutants emissions (black carbon, organic carbon, and sulfate), quantified the relative contributions of co-varied environmental factors, and explored the regulatory roles of background meteorological conditions across China. Our results showed that the heterogeneous GPP enhancement induced by emissions was dominated by cloud cover (CC) change. During its short-term effect, air temperature (Tair), vapor pressure deficit (VPD), and radiation (both quality and quantity) played a collectively non-negligible role in GPP variation, among which the universal diffuse radiation fertilization effect was generally far less than the benefits of brighter, cooler, and wetter environmental conditions. However, the sensitivity of GPP to an individual environmental variable was also altered by background meteorological gradients, whose changing pattern differed substantially among factors, indicating that the meteorological-regulated vegetation optimal photosynthetic range was a trade-off among heat, water, and light instead of being controlled by the univariable. This study implies that a deeper understanding of concurrent environmental variables is an effective way to reduce uncertainties in assessing the terrestrial carbon cycle perturbation exerted by human-induced emissions, especially under future scenarios with ongoing climate change. [ABSTRACT FROM AUTHOR]

Objective: To assess the effectiveness of multi-model strategies on healthcare-associated infections (HAIs) caused by multi-drug resistant organisms (MDROs) in rehabilitation units. Methods: A semi-experimental study was conducted in a rehabilitation unit with 181 beds from January 2021 to December 2022 in a teaching hospital with 4300 beds in China. In 2021, many basic prevention and control measures were conducted routinely. Based on the basic measures, strengthening multi-model strategies for the prevention and control of MDROs was pursued year-round since 1 January 2022. Results: A total of 6206 patients were enrolled during the study period. The incidence density of HAIs caused by MDROs decreased from 1.22 (95% CI, 0.96~1.54) cases/1000 patient-days in the pre-intervention period to 0.70 (95% CI, 0.50~0.95) cases/1000 patient-days (p = 0.004). Similarly, the incidence of HAIs in the intervention period was 50.85% lower than that in the pre-intervention period (2.02 (95% CI, 1.50~2.72) vs. 4.11 (95% CI, 3.45–4.85) cases/100 patients, p < 0.001). The rate of MDROs isolated from the environment decreased by 30.00%, although the difference was not statistically significant (p = 0.259). Conclusion: Multi-model strategies can reduce the incidence of HAIs and HAIs caused by certain MDROs in the rehabilitation unit. [ABSTRACT FROM AUTHOR]

The transmission rate is an important indicator for characterizing a virus and estimating the risk of its outbreak in a certain area, but it is hard to measure. COVID-19, for instance, has greatly affected the world for more than 3 years since early 2020, but scholars have not yet found an effective method to obtain its timely transmission rate due to the fact that the value of COVID-19 transmission rate is not constant but dynamic, always changing over time and places. Therefore, in order to estimate the timely dynamic transmission rate of COVID-19, we performed the following: first, we utilized a rolling time series to construct a time-varying transmission rate model and, based on the model, managed to obtain the dynamic value of COVID-19 transmission rate in mainland China; second, to verify the result, we used the obtained COVID-19 transmission rate as the explanatory variable to conduct empirical research on the impact of the COVID-19 pandemic on China's stock markets. Eventually, the result revealed that the COVID-19 transmission rate had a significant negative impact on China's stock markets, which, to some extent, confirms the validity of the used measurement method in this paper. Notably, the model constructed in this paper, combined with local conditions, can not only be used to estimate the COVID-19 transmission rate in mainland China but also in other affected countries or regions and would be applicable to calculate the transmission rate of other pathogens, not limited to COVID-19, which coincidently fills the gaps in the research. Furthermore, the research based on this model might play a part in regulating anti-pandemic governmental policies and could also help investors and stakeholders to make decisions in a pandemic setting. [ABSTRACT FROM AUTHOR]

Environmental geological disasters seriously threaten human lives and property. A reasonable analysis of the susceptibility to environmental geological disasters is the basis for disaster prevention and mitigation and can promote the sustainable development of regional economy. This study analyzes the susceptibility of environmental geological disasters, such as collapses, landslides, and debris flows in Helong City, China. Through investigation and comprehensive analysis, ten environmental, geological disaster causing factors, including stratum lithology, distance from the fault, elevation, slope, aspect, rainfall, distance from the water system, NDVI, distance from the road, and profile curvature, were extracted. Combined with GIS, a vulnerability analysis database of environmental geological disasters was established, and vulnerability zoning prediction was performed by using two models of information amount and a generalized regression neural network (GRNN). Then, disaster-vulnerability factors such as population density, road density, GDP, and land use type were added. The results show that the predicted results of the two models are similar to the actual survey results.. The environmental geological disasters in the study area are mainly low and not prone to occur, and the northeast and central areas are highly prone to environmental geological disasters, which are the key prevention and control areas in the study area. The coverage rate of high-vulnerability areas with a high degree of economic development is 8.63%, and the prediction results of the GRNN model are mostly distributed in spots and strips, which is more conducive to accurate disaster prevention and mitigation and cost reduction, promotes regional sustainable development, and has guiding significance for disaster prevention and control and urban planning and construction. [ABSTRACT FROM AUTHOR]

Located in the northern South China Sea, the Pearl River Estuary (PRE) is one of the most important estuaries in China and is surrounded by several megacities. Hypoxia mainly occurs in the bottom waters of the PRE during summer and is more prominent near the Humen outlet and the subestuary outside Modaomen and Jitimen. A well-validated three-dimensional (3-D) coupled physical-biogeochemical model was used to explore the changes in dissolved oxygen (DO) dynamics and hypoxic conditions in the PRE over an intra-annual cycle and elucidate the processes controlling the generation, development, and dissipation of hypoxia. In summer, oxygen consumption due to the high-intensity sediment oxygen demand (SOD) intensified by large inputs of riverine particulate organic carbon (POC) exceeded the DO supplemented by vertical diffusion (largely inhibited by strong fresh water–induced stratification), thus leading to a significant decrease in DO in the bottom waters; in other seasons, these DO source and sink terms were nearly balanced so that the bottom DO concentrations were maintained at higher levels. Moreover, the lag analysis shows that there is an approximately 2-month lag between riverine POC and SOD. By comparison, the low-oxygen area near Humen has a controlling mechanism distinct from that of the subestuary outside Modaomen and Jitimen. Specifically, the timely and sufficient oxygen supplement brought by vertical diffusion can replenish the bottom DO consumed by SOD in this region, and the formation and development of low-oxygen conditions (DO ≤ 4 mg L−1) is mainly affected by riverine low-oxygen inflows. In summary, our study clarified that the terrestrial organic pollutant input and low-oxygen water from the upper reaches have an important impact on the DO in different areas of the PRE, especially the low-oxygen area near Humen, which is controlled by the water quality of the upper reaches. This conclusion is of great significance for regional environmental management. [ABSTRACT FROM AUTHOR]

The excessive mold found in Three Squirrels' nuts and the clenbuterol abuse of Shuanghui are two infamous food safety incidents in China. We adopted push-pull-mooring theory to conduct a model and examined the factors influencing consumer short-term or long-term brand-switching or category-switching behaviors following the two food safety incidents. We employed multinomial logistic regression and structural equation modeling as tools to analyze 1027 valid questionnaires. The results, for the first time, revealed that perceived risk, alternative selectivity, alternative attractiveness, controllability attribution, and habits were key push, pull and mooring factors influencing Chinese consumers' brand and category switching from food brands under food safety crisis, and most importantly, that their influential paths differed greatly under the two food safety incidents, suggesting a different influential mechanism across two product categories (i.e., utilitarian food and hedonic food). These findings throw light on the predictors and mechanisms that affect consumer brand and category switching from food brands under food safety crisis and help associated food businesses develop more targeted and powerful crisis management and public relations strategies. [ABSTRACT FROM AUTHOR]

Wetland environmental pollution has become a global problem involving the ecological environment and human health. This study measured the concentration of seven potentially toxic elements (PTEs Hg, Cd, Zn, Cu, Cr, Pb, and As) in the soil upstream of the Xinli Lake wetland in China. Based on the fuzzy theory, the sources, spatial distribution, ecological risks, and health risks of pollutants are studied. The result shows that the concentrations of the seven potentially toxic elements are close to or exceed the background value, and their spatial distribution showed irregular changes. The soil upstream of the wetland has not been seriously polluted, and Cd, which has higher bioavailability, is the priority element for ecological risk. Pollutants do not harm human health; children face higher health risks; Pb and As have the highest carcinogenic and non-carcinogenic risks, respectively. Zn, Cu, Cr, Pb, and As in the study area are derived from agricultural activities, while Hg and Cd are mainly affected by soil-forming parent materials. Attention should be paid to controlling the intensity of agricultural activities to avoid excessive input and accumulation of pollutants that would harm the ecological environment and human health. [ABSTRACT FROM AUTHOR]

Freeze–thaw circulation under different moisture contents is the main influencing factor of the soil strength characteristics at a dumping site. The fine-grained sand materials of an internal dumping site in the Yuanbaoshan open-pit mine of China were selected as the research object; the changes of soil strength and deformation characteristics of 5 types of freeze–thaw (F–T) cycles were studied under 8 types of moisture contents. The stress–strain curve of soil sample shows strain hardening after different F–T cycles. The shear strength of the soil material decreases unevenly with increasing number of F–T cycles, and the greatest decrease in the shear strength occurs after the first F–T cycle. Under the condition of the same F–T cycles, the cohesion and internal friction angle (shear strength parameters) of the soil material decrease nonlinearly with increasing moisture content and decay in the form of a power function. For the same moisture content, the effect of F–T cycling on the internal friction angle of the soil is small, but the cohesion of the soil decreases as the number of F–T cycles increases, eventually stabilising. A quadratic polynomial equation can accurately describe the quantitative relationship between the cohesion and number of F–T cycles, at the same time, the unified regression equations of cohesion, moisture content and F–T cycle are established. The research results provide an important idea for the design of dumps and slope stability analysis, especially for the first year after dumping. [ABSTRACT FROM AUTHOR]

Increasing forest soil organic carbon (SOC) storage is important for reducing carbon dioxide (CO2) emissions from terrestrial ecosystems and mitigating global climate change. Although the effects of altitude, temperature and rainfall on organic carbon have been studied extensively, it is difficult to increase SOC storage by changing these factors in actual forest management. This study determined the SOC, soil physical and chemical properties, nutrient elements, heavy metal elements, soil minerals and microbial biomass in the 0–140‐cm soil layer of the monsoon broad‐leaved forest in the acid red soil region of southwestern China by stratification. We tried to identify the soil factors affecting the SOC storage of the forest in the acid red soil region and determine the weights of the factors affecting the SOC, with the aim of improving the SOC retention capacity in forest management by changing the main soil factors affecting SOC storage. The results showed that the soil factors affecting the forest SOC storage in this area are total nitrogen (N, 22.7%) > soil water content (19.9%) > active iron (including poorly crystalline iron, Feo, 15.5%) > pH (9.5%) > phosphorus (P, 9.4%) > aluminium (Al, 8.9%) > silicon (Si, 7.1%) > sulphur (S, 6.8%). Of these factors, N, the water content, Feo, and P are practical factors for forest management, whereas the pH, Al, Si and S are not. SOC was significantly positively correlated with the soil N concentration, water content, active iron content and P concentration (p <.05). In acidic red soil areas, with active iron as the highlight, N, soil water content, phosphorus and active iron jointly regulate the forest SOC storage capacity. Consequently, in actual forest management, any measures to promote soil N and water content and to activate inactive iron can enhance the storage of SOC, as appropriate input of N and P fertiliser and irrigation in dry years and the dry season. Highlights: The soil environmental factors affecting SOC storage in forest soil are quantifiedActivation of inactive iron helps SOC storage in forest soilIrrigation and N and P input are effective for helping SOC storage in forest soilN, WC, P and Feo jointly regulate SOC in tropical acid red soil forest [ABSTRACT FROM AUTHOR]

Trace intensity is defined as mean total trace length of discontinuities per unit area, which is an important geometric parameter to describe fracture networks. The probability of each trace appearing in the sampling surface is different since discontinuity orientation has a scatter and is probabilistically distributed, so this factor should be taken into account in trace intensity estimation. This paper presents an approach to estimate the two-dimensional trace intensity by considering unequal appearing probability for discontinuities sampled by rectangular windows. The estimation method requires the number of discontinuities intersecting the window, the appearing probability of discontinuities with both ends observed, one end observed, and both ends censored, and the mean trace length of discontinuities intersecting the window. The new estimator is validated by using discontinuity data from an outcrop in Wenchuan area in China. Similarly, circular windows are used along with Mauldon's equation to calculate trace intensity using discontinuity trace data of the same outcrop as a contrast. Results indicate that the proposed new method based on rectangular windows shows close accuracy and less variability than that of the method based on circular windows due to the influence of finite sample size and the variability of location of the window and has advantage in application to sampling surfaces longer in one direction than in the other such as tunnel cross sections and curved sampling surfaces such as outcrops that show some curvature. [ABSTRACT FROM AUTHOR]

Blechnum orientale L. is a traditional, medicinal fern found in China. To assess the characteristics of heavy metals and As accumulation, the fronds, roots, and the rooting soils of this fern were sampled from urban, suburban, and rural woodlands across Guangdong Province in southern China. The concentrations of As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn in both the fern and its rooting soils were separately detected by ICP-MS. Contamination levels of woodland rooting soils were also assessed using both a single pollution index and the Nemerow pollution index. Both the metal concentrations and the pollution index showed that soils from urban, suburban, and even rural woodlands were adversely contaminated by As, Cd, Hg, and Pb. Based on transfer factor, B. orientale had good translocation of As, Hg, and Mn, but poor translocation of Cd, Cr, Ni, Cu, Ni, Pb, and Zn from the roots to the fronds. This result suggests that this fern could be an excluder to latter metals. Despite the significantly higher levels of metals in the roots as compared with the fronds, the low bioaccumulation factor suggests that this fern has a weak capacity for metal accumulation. [ABSTRACT FROM AUTHOR]

Wetlands are recognized as one of the most important natural environments for humans. At the same time, heavy metal pollution has an important impact on wetlands. China's Raoyanghe Wetland is one of the most important natural wild species gene banks in China. Eight heavy metal elements (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) in surface layer and deep layer soils were analyzed using statistical-, pollution index-, and Nemerow index-based methods, the Hakanson potential ecological risk index method, and principal component and cluster analyses. The results showed that the maximum concentrations of heavy metals exceeded the background values in the core area and buffer zone of the wetland, but the heavy metal content of the soils was generally low and did not exceed 30%. With the exception of Hg, heavy metal concentrations showed strong spatial differentiation. The differences between the surface layer and deep layer soils of the core area were smaller than in the buffer zone. With the exception of Cd, a clear vertical zonation in the buffer zone soils was observed, showing greater evidence of external influences in this zone than the core. With the exception of partial surface soils, which indicated a safe level of pollution in the core area, all other soils were classified as having a ‘mild’ level of pollution. Thus, the wetland is moderately polluted, with both the core area and the buffer zone presenting a low level of potential ecological risk. According to the results of the present study, heavy metal contaminants in the wetland soils were found to be derived mainly from the natural sources. [ABSTRACT FROM AUTHOR]

Abstract: This paper simulates the effects of China's growing government debt in a computable equilibrium model of overlapping generations. Our model assumes that the government increases debt to finance its spending in the short run, and then increases taxes or cuts spending to keep the debt–GDP ratio constant. The spending‐driven government debt increases public capital and output in the short run, but decreases private investment, total capital stock, output, and net exports in the long run, and makes the future generations worse off. Among various means of debt control, a decrease in government spending seems to be the least harmful to private investment, capital stock, and output while an increase in capital taxation is most detrimental. [ABSTRACT FROM AUTHOR]

This paper develops a dynamic equilibrium model of overlapping generations to study the effect of an introduction of a retail sales tax (RST) in China. Total government tax revenue is fixed, consumption-type value-added tax (VAT) is reduced in response to the introduction of RST, and an output tax exists. An introduction of RST accompanied by a decrease in VAT increases capital accumulation and welfare in the steady state. In the transition period, an introduction of RST accompanied by a decrease in VAT increases capital accumulation but decreases the current generation's welfare. Simulations based on the data from China show that introducing an 8 percent RST increases capital accumulation by 0.43 percent in the steady state. [ABSTRACT FROM AUTHOR]

This paper projects China's national savings through 2040 based on China's national account data, demographic data, and data on rural and urban life-cycle income and consumption. Our baseline projections show that China's national saving in 2040 will be 16 times the current national saving. The annual growth rate of wealth will decline from 16.3 percent in 2012 to 9.5 percent in 2040. Lowering the growth rate of wealth accumulation to the current rate of return to wealth increases consumption through 2040; lowering the growth rate of wealth further may increase consumption more in the short run, but less in the long run. [ABSTRACT FROM AUTHOR]

China's population aging problem is more severe than other countries because of the one-child policy adopted in the early 1980s, and the current social security system is not sustainable. A two-sector overlapping generations model is developed to analyze China's social security reforms. It is shown that if the government does nothing to reform the system, maintaining the current replacement and contribution rates, social security debt will be explosive. Various reforms are considered, including adjusting the replacement rate while keeping the contribution rate constant, increasing the contribution rate while maintaining the current replacement rate, increasing the retirement age with the contribution rate being unchanged, increasing the retirement age with the replacement rate being unchanged, and switching to a fully-funded system by using government assets to pay the implicit social security debt. The effects of these reforms on capital accumulation, the output, and the welfare for each generation are simulated and compared. [ABSTRACT FROM AUTHOR]

Highlights: [•] Simulate impact of conservation tillage and optimal fertilization on nutrient loss. [•] Conservation tillage achieves effective nutrient loss reduction. [•] No-tillage combined with straw mulch is more efficient than using no-tillage solely. [•] Optimal fertilization greatly reduces nutrient loss with small impact on crop yield. [Copyright &y& Elsevier]

Tea plantations are rapidly expanding in China and other countries in the tropical and subtropical zones, driven by relatively high private economic benefit. However, the impact of tea plantations on the regional environment, including ecosystem services and disservices are unclear. In this study, we developed an assessment framework for determining the private economic benefits and environmental externalities (the algebraic sum of the regulating services and disservices) of tea plantations in China. Our results showed that tea plantations provided private economic benefits of 5,652 yuan ha year (7.6 yuan = 1 USD in 2007) for tea farmers, plus positive environmental externalities of 6,054 yuan ha year for the society. The environmental externalities were calculated as the sum of the value of four regulating services, including carbon sequestration (392 yuan ha year); soil retention (72 yuan ha year); soil fertility protection (3,189 yuan ha year) and water conservation (2,685 yuan ha year), and three disservices, including CO emission (−39 yuan ha year), NO emission (−137 yuan ha year) and nonpoint source pollution (−108 yuan ha year). Before the private optimal level, the positive environmental externalities can be maintained by private economic benefits; if a social optimal level is required, subsidies from government are necessary. [ABSTRACT FROM AUTHOR]

Abstract: A coupled physical and sediment transport model was used to study the mass flux budgets of water and suspended sediments in the Pearl River Delta (PRD). The coupled model incorporates the Pearl River network, the Pearl River Estuary (PRE) and adjacent coastal waters in one overall modeling system. The results indicate that the river network and the PRE both have pronounced temporal and spatial variability in water and sediment fluxes, in hydrodynamic features and in sediment depositional patterns. In the river network, the riverine fluxes of water and suspended sediments are dominated by the West River, and those that are exported to the PRE (defined as the estuarine fluxes) are primarily contributed by Modaomen. The river outlets are highly responsive to the main tributaries in terms of water and sediment fluxes, revealing a close coupling between the upstream and the downstream boundaries. Most of the annual riverine and estuarine fluxes occur in the wet season, approximately 74% of the water flux and riverine and estuarine fluxes of suspended sediments of 94% and 87%, respectively. Although the water and sediment transport is dominated by river discharge, the tides are also an important factor, especially in regulating the structures of seasonal deposits in the river network (deposition in the wet season and erosion in the dry season). In the PRE, various types of physical forcing, including river discharge, monsoon winds, tides, coastal currents and the gravitational circulation associated with a density gradient, operate in concert to control the water and sediment transport in the estuary. Most of the oceanic fluxes of water and suspended sediments entering the South China Sea take place in the dry season and are primarily conveyed by strong western coastal currents. The PRE is a sedimentary system characterized by intricate depositional structures in space and time. Several depositional patterns and the associated driving mechanisms were identified. A fan-shaped deposition zone, the most intense deposition belt in the PRE, was found in the outer Modaomen Bay, where hypoxia has been reported. This work provides a basis for subsequent water quality applications in the PRD, including studies of hypoxia, eutrophication and maximum turbidity. [Copyright &y& Elsevier]

Abstract: This paper analyzes the size and structure of China''s government debt. In addition to explicit government debt, we consider three types of government contingent liabilities: local government debt, university debt, and state banks’ nonperforming loans. The size of each types of debt is estimated and the reasons for the emergence of each type of debt are analyzed. International comparisons are made and it is found that China''s government debt is larger than many other developing countries. To insure fiscal sustainability and to leave rooms for future expansionary fiscal policies, the government should reduce contingent liabilities. [Copyright &y& Elsevier]

Abstract: Quantifying carbon (C) storage is an essential task when assessing the particular C budget of a specific ecosystem. Tea is an important cash crop, and tea plantations commandeer large amounts of arable land throughout the world. In China, 1.3 million hectares dedicated to tea plantation cultivation have been established throughout the last five decades, resulting in a current total of 1.6 million hectares countrywide. For this study, C density and C pools related to biomass as well as the soil and the litter layer were estimated based upon 563 biomass and 255 soil samples procured from both field survey data and data obtained from literature. Subsequent estimations reveal that the total amount of C stored within biomass, the litter layer, and the soil of tea plantations in China is 83.3Tg C (1Tg=1012 g C), 8.0Tg C and 225.0Tg C, respectively, and the average C density of biomass, the litter layer, and the soil is 50.90Mg, 4.91Mg, and 137.5Mg C ha−1, respectively. Despite varying climatic conditions and tea plant types specific to the three separate zones, no significant differences were found in biomass C densities. This suggests that the similar managerial (e.g., pruning) practices applied in their maintenance may in fact be the primary factor that shapes tea plantation C storage. Although tea plantations store less C than do resident mature forests, the considerable C storage of tea plantations makes them a factor of critical importance in regional C accounting that cannot be ignored in future research and policymaking initiatives. [Copyright &y& Elsevier]

Using a large-scale enclosed sea area in northern Hangzhou Bay as a case study, the trophic interactions, energy flows, and ecosystem properties of a coastal artificial ecosystem were analyzed by ecotrophic modeling using Ecopath with Ecosim software (EwE, 5.1 version). The model consists of 13 functional groups: piscivorous fish, benthic-feeding fish, zooplanktivorous fish, herbivorous fish, crabs, shrimp, mollusca, infauna, carnivorous zooplankton, herbivorous zooplankton, macrophytes, phytoplankton, and detritus. Input information for the model was gathered from published and unpublished reports and from our own estimates during the period 2006-2007. Results show that the food web in the enclosed sea area was dominated by a detritus pathway. The trophic levels of the groups varied from 1.00 for primary producers and detritus to 3.90 for piscivorous fish in the coastal artificial system. Using network analysis, the system network was mapped into a linear food chain, and five discrete trophic levels were found with a mean transfer efficiency of 9.8% from detritus and 9.4% from primary producer within the ecosystem. The geometric mean of the trophic transfer efficiencies was 9.6%. Detritus contributed 57% of the total energy flux, and the other 43% came from primary producers. The ecosystem maturity indices-total primary production/total respiration, Finn's cycling index, and ascendancy-were 2.56, 25.0%, and 31.0%, respectively, showing that the coastal artificial system is at developmental stage according to Odum's theory of ecosystem development. Generally, this is the first trophic model of a large-scale artificial sea enclosure in China and provides some useful insights into the structure and functioning of the system. [ABSTRACT FROM AUTHOR]

Abstract: Hypoxia in the Pearl River Estuary (PRE) during summer is one of the problems caused by increasing anthropogenic pollutant inputs due to population increase and economic development in recent years. The mechanism for hypoxia in the PRE has to be understood firstly before any management policy can be established. A three-dimensional water quality model was therefore developed to study the dissolved oxygen (DO) budget of the PRE in summer and to identify the roles that various physical and biochemical processes played in DO dynamics. Results show that above the pycnocline, horizontal transport of DO is mainly balanced by reaeration, and photosynthesis appears to play a more important role in the shelf area than inside the PRE due to reduced turbidity. Below the pycnocline, horizontal transport of DO is balanced by biochemical processes. Regarding the DO depletion processes in the PRE above the pycnocline, DOC oxidation is the largest consumer of DO, while nitrification and phytoplankton respiration rank second and third, respectively. Below the pycnocline, SOD dominates DO depletion processes, following by DOC oxidation, nitrification and phytoplankton respiration. The dominant role of SOD in DO depletion processes of the PRE is caused by the shallow topography and high deposition rate of POC. Vertical DO transport in the PRE shows remarkably spatial variability due to complicated hydrology and topography in the PRE. The vertical DO fluxes are dominated by advective fluxes as a result of intense tidal forcing and gravitational circulation in deep channels, while diffusive fluxes dominate in the vertical fluxes within the shoal area as a result of increasing DO vertical gradient due to hypoxia. [Copyright &y& Elsevier]

Abstract: Over recent years, accelerated anthropogenic nutrient discharges have exerted great pressure on the water quality management in the Pearl River Delta (PRD), China. There is a concern about the eutrophication processes and hypoxia in this region. A better understanding of the origins and transport of nutrients is required before accurate prediction of impacts of nutrients on eutrophication and hypoxia in the PRD can be anticipated. Therefore a coupled physical–biological model is developed to simulate the fluxes and transformations of nutrients in the PRD. The coupled model combines a one-dimensional model for the river network (called the RNPRD) and a three-dimensional model for the Pearl River Estuary (PRE), which are both physical–biological models. The model is calibrated and validated to different sets of field data. The model results of water surface elevation, discharges, salinity, suspended sediment and water quality variables are in reasonable agreement with the observational data, suggesting that the model is robust enough to capture the physical and biogeochemical dynamics in the PRD. Also, the fluxes and transformations of carbonaceous biochemical oxygen demand (CBOD), ammonia nitrogen (NH3), nitrate plus nitrite nitrogen (NO23) and inorganic phosphorus (IP) in July 1999 (wet season) are explored and discussed. Results show that the RNPRD act as a source for NO23, but a sink for CBOD, NH3 and IP that consumes 50%, 37% and 11% of their external loads, respectively. The riverine fluxes of nutrients exported from the RNPRD to the PRE are generally controlled by high river discharge and significantly contributed by upstream inputs. The riverine fluxes are the largest inputs of nutrients to the PRE. The PRE also behaves as a source for NO23, but a sink for CBOD, NH3 and IP that consumes 90%, 80% and 16% of their external loads, respectively. The estuarine fluxes of nutrients exported from the PRE to the South China Sea are significantly contributed by the external and internal sources of nutrients in the PRE. In the RNPRD, the transformations of CBOD, NH3 (also NO23) and IP are dominated by carbonaceous oxidation, nitrification and deposition, respectively. Regarding the PRE, carbonaceous oxidation, nitrification and phytoplankton uptake are identified as the dominant processes with respect to CBOD, NH3 (also NO23) and IP. Unlike the RNPRD, the phytoplankton dynamics and internal sources of nutrients play an important role in the nutrient budgets in the PRE. Also, seasonal variations of the nutrient budgets in the PRD are discussed. Model results indicate that the dry season and wet season have a similar feature in terms of transformations of nutrients, but show significant seasonal variations in terms of nutrient fluxes. At the same time, the PRE is compared to the Changjiang and Mississippi Rivers with regard to differences in nutrient inputs between these similar river-dominated systems. [Copyright &y& Elsevier]

The identification and quantification of pharmaceutical and personal care products (PPCPs) in aquatic ecosystems is critical to further studies and elucidation of their fate as well as the potential threats to aquatic ecology and human health. This study used mass balances to analyse the sources, transformation, and transport of PPCPs in rivers based on the population and consumption habits of residents, the removal level of sewage treatment, the persistence and partitioning mechanisms of PPCPs, hydrological conditions, and other natural factors. Our results suggested that in an urbanized river of Guangzhou City, China, the daily consumption of PPCPs was the main reason for the variety of species and concentrations of PPCPs. Through the determination of PPCPs in the river water samples and a central composite design (CCD) methodology, the dominant elimination mechanisms of caffeine and carbamazepine from river water were photolysis and biodegradation, but that of triclosan was sorption rather than biodegradation. The mass data of 3 PPCPs were estimated and corroborated using the measured data to evaluate the accuracy of the mass balance. Finally, caffeine, carbamazepine and triclosan discharged from the Shijing River into the Pearl River accounted for 97.81%, 99.52%, and 28.00%, respectively, of the total mass of these three compounds in the surface water of Shijing River. The results suggest that photolysis are the main process of natural attenuation for selected PPCPs in surface waters of river systems, and the transfer processes of PPCPs is mainly attributed to riverine advection. In addition, the low concentration of dissolved oxygen inhibited the degradation of PPCPs in the surface water of Shijing River. Image 1 • 13 of 15 Target PPCPs were detected in the surface water of the Shijing River. • A mass balance of caffeine, carbamazepine and triclosan was addressed. • The source of PPCPs in urban rivers depends on the consumption of residents and the improvement of sewage treatment system. • The fate of these PPCPs was mainly dependent on advection and photolysis. The occurrence and fate of PPCPs by combining field observations, laboratory experiments and a mass balance analysis was investigated in an urbanized river. [ABSTRACT FROM AUTHOR]

Rural China faces a shortage of safe drinking water. There are significant challenges associated with small centralized water supply systems and decentralized water supply systems. Many rural residents use point-of-use water treatment systems to ensure the safety of their drinking water. The actual water purification effect and applicability of these water treatment systems in small centralized and decentralized water supply systems need to be determined urgently. In this study, the water quality index (WQI) method was applied for the first time in rural areas to evaluate the effectiveness of point-of-use water treatment systems. A total of 67 reverse osmosis water treatment systems were tested. The rate of compliance with drinking water standards of the decentralized water supply was low (37%). Compared with untreated water, the use of a reverse osmosis water treatment system improved the rate of compliance with drinking water standards, but this effect was not satisfactory (8%). Among the factors potentially affecting the purified water quality of point-of-use water treatment systems (e.g., service time of the water treatment system, service time of the filter element, and type of water source), the service time of the filter element had the most significant influence on the water quality. If the filter element had not been replaced for a long period, the removal effect of the water treatment system on the total hardness, sulfide, copper, and ammonia nitrogen was significantly affected, reducing the quality of the purified water. To ensure the safety of drinking water, it is recommended to replace the filter element of a reverse osmosis water treatment system at least once a year. [ABSTRACT FROM AUTHOR]

[Display omitted] • Twelve new aniline derivatives and three new natural products were isolated from the volva of P. rubrovolvatus. • The relative and absolute configurations were confirmed by NOESY correlations and comparison between experimental and calculated ECD spectra. • Compounds 4, 9 and 10 exhibited good anti-inflammatory activity against LPS-induced NO production in RAW264.7 macrophages. Phallus rubrovolvatus is an important commercially cultivated mushroom species in China. However, the volva of P. rubrovolvatus usually discarded as a by-product due to the unpleasant flavor and difficulty in processing. In this study, we investigated the chemical constituents and bioactivities of the volva of P. rubrovolvatus. As a result, fifteen rare aniline derivatives, including twelve new compounds (1 – 11 , 14) and three new natural products (12 , 13 , 15) were isolated from the volva. Their structures were determined using 1D and 2D NMR data and HR-ESI-MS data, while the relative and absolute configurations were confirmed by NOESY correlations and comparison between experimental and calculated ECD spectra. In addition, compounds 1 – 15 were tested for anti-inflammatory activity against lipopolysaccharide (LPS)-induced NO production in RAW264.7 macrophages. Compounds 4 , 9 and 10 exhibited anti-inflammatory activity with IC 50 values ranging from 12.5 to 15.6 μM. [ABSTRACT FROM AUTHOR]

• Moisture, N & Fe ox are the most critical soil environmental factors for SOC storage. • N, S and P input can activate crystalline Fe in soil to further promote SOC storage. • Magnetic fertilizer application is vital to improve SOC storage in tea plantations. Increasing soil organic carbon (SOC) reserves in agricultural land is important for mitigating global climate change. The soil environmental factors that affect SOC storage in agricultural cultivation are relatively easy to manage, but the effects of these factors on SOC have not been studied systematically, especially the relative weight of each factor is still unclear. In this study, more than 30 soil environmental factors including SOC, soil physical and chemical properties, mineral types, and microorganisms present in the 0–140 cm soil layer were determined hierarchically within tea plantations. The main and secondary factors affecting SOC storage were then analyzed quantitatively using a structural equation model. The most important factors affecting SOC storage in tea plantations included water content (18.9 %), total nitrogen (N, 18.8 %), oxalate-extractable iron (active iron, poorly crystalline iron, Fe ox , 16.3 %), sulfur (S, 13.1 %), total phosphorus (P, 8.6 %), calcium (6.1 %), oxidation reduction potential (5.4 %), clay (4.5 %), bromine (4.3 %), and manganese (4.0 %). Variations in soil temperature and pH on this small scale were small and thus these factors had negligible effects on SOC storage in this study. Organic fertilizer application increased C, N, S, and P concentrations, which can contribute to SOC storage. Appropriate irrigation can also improve SOC storage. We identified a set of Fe -N- S-P coupling mechanisms that promoted SOC storage. Soils with high Fe, N, and S concentrations, high water content, and high oxidation reduction potential relate to an increased Fe ox concentration, which is important for enhancing SOC stability. Therefore, the application of magnetic (iron oxide) fertilizer to increase Fe ox in soil promotes SOC storage. [ABSTRACT FROM AUTHOR]

The zircon and apatite fission track analyses show four age groups of 59–144 Ma, 114–100 Ma, 72 Ma and 52–32 Ma, reflecting four tectonic thermal events in the Chakabeishan area since the Middle–Late Jurassic. The zircon fission track ages are distributed in 159–72 Ma, revealing the mineralization age in the Chakabeishan area. The thermal history simulation results indicate that the Chakabeishan area has experienced three uplift stages: the first stage of 120–60 Ma, corresponding to a rapid cooling and uplift, is a record of the collision and continuous convergence of the Lhasa block and the Qiangtang block; the second stage of 60–18 Ma is relatively steady uplift; the third stage of 18–0 Ma presents a rapid uplift process related to continuous collision between the Indian and Eurasian Plates. [Display omitted] • Four tectonic episodes of 159–144, 114–100, 72 and 52–32 Ma were revealed. • Three uplift stages of 120–60, 60–18 and 18–0 Ma with uplift amount of 3.27 km. • Each uplift stage is a response to collision events between different plates. • Metallogenic periods (three periods) and ages (Late Jurassic–Cretaceous) were confirmed. The Chakabeishan area is located in the northern margin of the Qaidam Basin, Northwest China, and is an important lithium mining area. However, there is a relatively lower research degree and lack of data constraints of tectonic uplift and exhumation. Using fission track technology, new apatite and zircon fission track results have been reported for the first time in order to reveal the tectonic processes and uplift histories of this area. A total of 11 sample results were obtained, these ages could be divided into four groups, namely, 159–144 Ma, 114–100 Ma, 72 Ma and 52–32 Ma, revealing four periods of tectonic activities. Thermal history modelling provided three episodes of uplift at 120–60 Ma, 60–18 Ma and 18–0 Ma. In the first stage, the Southern Qilian Mountains was reactivated and subducted southward due to collision of the Lhasa and the Qiangtang blocks, resulting in rapid uplift in this area. The second stage is tectonic quiescence period corresponding to a relatively steady uplift. The third stage showing rapid uplift caused by the collision between the Indian and Eurasian Plates. The average uplift rate and total uplift amount of the three stages calculated according to the geological thermal histories are 0.039 km/Myr and 3.27 km, respectively. Using the age–closure temperature method, the exhumation rate has been calculated as 0.034–0.148 km/Myr from zircon closure–temperature of 250 °C to apatite closure–temperature of 100 °C and 0.049–0.076 km/Myr form the apatite closure–temperature of 100 °C to 15 °C of surface temperature. The exhumation rate is fastest from the Late Cretaceous to Eocene and has then changed a little since the Eocene, with the average exhumation rate of about 0.059 km/Myr. Synthesizing the zircon ages and geological characteristics, this area is characterized by multi–stages mineralization, and the metallogenic age is mainly in the Late Jurassic–Cretaceous. [ABSTRACT FROM AUTHOR]

A trophic model of an intertidal mangrove-based polyculture system in Pearl River Delta, China, was constructed using the Ecopath with Ecosim software. This polyculture system was chosen since it is the first integrated multi-trophic aquaculture (IMTA) system that was constructed on the basis of mangrove planting in China. The energy flows, ecosystem property, and carrying capacity of tilapia in the polyculture system were analyzed and evaluated. The results show the trophic level of 1.00 for primary producers and detritus to 2.85 for grass carp. The geometric mean of the trophic transfer efficiencies was 7.0%, with 7.2% from detritus and 6.8% from primary producers within the system. The ecosystem property indices show that this polyculture system has a high value of total primary production/total respiration (TPP/TR) and total primary production/total biomass (TPP/TB), together with low Finn's cycled index (FCI), Finn's mean path length (FML), and connectance index (CI), indicating that this system is at a development stage according to Odum's theory. The principal fish cultured in the system is tilapia, and mixed trophic impacts (MTI) show that tilapia has a marked impact on most compartments in this system, and the carrying capacity was found to be a tilapia culture biomass of 5.8tha−1 in the system. [Copyright &y& Elsevier]

Objectives: Many studies have confirmed that antibacterial agents can disrupt the human gut microbiota. In China, Tanreqing injection (TRQ) is a drug with antibacterial activity that is widely used in the treatment of respiratory infections. However, its specific influence on gut microbiota remains unclear. This study aimed to investigate the effect of TRQ on the gut microbiota of healthy volunteers., Methods: Twelve healthy adults received 20 ml of TRQ intravenously daily for 7 consecutive days. At six timepoints (Pre, on D1, D3, D5, D7 and follow-up visit) fecal samples were collected and analyzed using 16S rRNA gene sequencing., Results: Eleven people were included in the analysis finally. TRQ did not significantly alter gut microbiota diversity or richness (Shannon and Simpson and Chao1 index) in healthy people during the intervention. Gut microbial structure was stable (weighted and unweighted Unifrac). Using a machine learning method based on PLS-DA analysis, the separation trend on D7 at the genus level was found, returning to baseline two days after discontinuation. The abundance of major genus fluctuated on D7 compared with that prior to treatment, including an increase of unclassified&#95;f&#95;Enterobacteriaceae (13.0611%), a decrease of Bifidobacterium and Escherichia-Shigella (6.887%, 10.487%). Functional prediction analysis did not reveal any significant difference., Conclusions: Our study showed short-term use of TRQ at conventional doses may not cause perturbations to the gut microbiota in healthy adults. This finding provides some useful information for the safe use of TRQ in the treatment of respiratory infections., Clinical Trial Registration: https://www.medicalresearch.org.cn/, identifier MR-31-24-014367., 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 © 2024 Li, Zhang, Liu, Zhou, Liu, Yuan and He.)

Objectives: This study aimed to develop and validate a predictive nomogram for diagnosing radicular grooves (RG) in maxillary lateral incisors (MLIs), integrating demographic information, anatomical measurements, and Cone Beam Computed Tomography (CBCT) data to diagnose the RG in MLIs based on the clinical observation before resorting to the CBCT scan., Materials and Methods: A retrospective cohort of orthodontic patients from the School and Hospital of Stomatology, Wuhan University, was analyzed, including demographic characteristics, photographic anatomical assessments, and CBCT diagnoses. The cohort was divided into development and validation groups. Univariate and multivariate logistic regression analyses identified significant predictors of RG, which informed the development of a nomogram. This nomogram's performance was validated using receiver operating characteristic analysis., Results: The study included 381 patients (64.3% female) and evaluated 760 MLIs, with RG present in 26.25% of MLIs. The nomogram incorporated four significant anatomical predictors of RG presence, demonstrating substantial predictive efficacy with an area under the curve of 0.75 in the development cohort and 0.71 in the validation cohort., Conclusions: A nomogram for the diagnosis of RG in MLIs was successfully developed. This tool offers a practical checklist of anatomical predictors to improve the diagnostic process in clinical practice., Clinical Relevance: The developed nomogram provides a novel, evidence-based tool to enhance the detection and treatment planning of MLIs with RG in diagnostic and therapeutic strategies., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The influence of overlying hydrodynamics on the exchange behaviour and fluxes of heavy metals at the sediment-water interface (SWI) is poorly understood. In the study, metals exchange behaviour and exchange rate at the SWI under resuspended and undisturbed scenario were investigated The results showed that dissolved Cr, Cu, Zn, and Pb concentrations increased rapidly to attain maximum values between 0.3 and 0.5 N·m -2 after the sediment resuspended. Following the quick release, metals concentrations gradually decreased and remained at relatively low levels, especially for Cu and Zn. Meanwhile, Cu, Zn, and Pb had higher potential remobilization potential in the undisturbed case. Calculating with the hydrodynamics in the Modaomen, the metals efflux under the resuspension scenario could reach 0.55 to 4130.83 mg·m -2 ·yr -1 , which were 1-3 orders of magnitudes higher than the undisturbed case. Whether or not resuspension events occurred, estuarine sediments were source of heavy metals, especially in the weakly mixed zone., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Shiziyang Bay, located in the upstream of the Pearl River Estuary, has frequently suffered from hypoxia since 2000, which has persisted in recent years despite effective controls on anthropogenic pollutant loads. To explore the underlying causes, changes in dissolved oxygen (DO), nutrients, chemical oxygen demand (COD), and chlorophyll a (Chl a) along the bay in response to altered pollutant inputs were investigated using observations collected in summers of 2015-2019 and historical data during 2000-2008. In addition, DO sources and sinks were calculated based on data from August 2020 and laboratory incubations for water column respiration (WCR) and sediment oxygen uptake, and were compared with their equivalents in August 2008 to elucidate changes in primary processes controlling hypoxia. The results showed that ammonia has decreased significantly with pollutant control, while other parameters responded in different trends, especially for Chl a (with a substantial increase over time). The intensified eutrophication contributed to high COD levels, leading to a strong WCR (as dominant oxygen depletion) close to that in the 2000s and thereby maintaining low-oxygen conditions despite reduced effluent discharges. The shifted primary oxygen-consuming substances from allochthonous inputs to in-situ phytoplankton production were also evidenced by significant correlation between oxygen consumption rate and Chl a in recent data. Simultaneously, the enhanced algal blooms could also modulate oxygen supply, resulting in higher photosynthetic oxygen production and lower air-sea reaeration compared with the past. Furthermore, the impact of major environmental changes on exacerbated eutrophication was explored and it was speculated that notable declined sediment loads would be important by improving light conditions to promote phytoplankton proliferation in the bay. Collectively, substantial control on eutrophication as well as tracking DO source-to-sink processes is of great importance to mitigate hypoxia in Shiziyang bay., 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.)

In late-developing regions, new technologies and previous experiences are applied to reduce the impact of economic development on environmental pollution in the early stages. After economic development has reached a certain level, the application of new environmental remediation technologies and methods can accelerate environmental restoration. Therefore, we hypothesized that the relationship between economic development and environmental pollution would exhibit an inverted V in late-developing regions. We examined water quality changes in 353 monitoring sections of 76 urban rivers in Kunming, southwestern China, over the last 33 years to assess the impact of economic development on river water quality. The results indicate that the relationship between the comprehensive pollution index of urban rivers and the economy shows an inverted V, supporting our hypothesis. The inverted V could be divided into four areas: an environmental self-purification area (<2170 USD); an economic development environmental destruction area (2170-5240 USD); an economic development feedback environment area (5240-11,255 USD); and an economic development promotion environment area (>11,255 USD). On the time axis of economic development, the relationship between economic development and environmental pollution is closer to an inverted U in relatively early developing regions, but the experience with and application of new technologies causes the relationship to change from an inverted U to an inverted V in relatively late-developing regions., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2022. Published by Elsevier B.V.)

Objective: New subtyping classification systems of Parkinson's disease (PD) have been proposed for phenotyping patients into three different subtypes: mild motor-predominant (PD-MMP), intermediate (PD-IM) and diffuse malignant (PD-DM). The quality of life (QoL) underlying the novel PD clinical subtypes is unknown. This study aimed explore the feasibility of the classification in Chinese PD patients and to investigate the potential heterogeneous determinants of QoL among the three subtypes., Methods: 298 PD patients were enrolled, including 129 PD-MMP patients, 121 PD-IM patients and 48 PD-DM patients. All patients completed the QoL assessment, clinical evaluations and neuropsychological tests. Univariate linear analysis and multiple stepwise regression analysis were performed to identify determinants of QoL., Results: Compared to PD-MMP patients, PD-IM and PD-DM patients had more impaired QoL. The Geriatric Depression Rating Scale (GDS) score, Non-Motor Symptoms Questionnaire (NMSQ) score, Unified Parkinson's Disease Rating Scale part III (UPDRS-III) score and Epworth Sleepiness Score (ESS) were independent contributors to QoL in PD-MMP patients. The GDS score, ESS and sniffin' sticks screening 12 test score were independent contributors to QoL in PD-IM patients. The GDS score and Mini Mental State Examination score were independent contributors to QoL in PD-DM patients., Interpretation: The new novel subtyping classification is feasible for Chinese PD patients. Although depression was the most crucial determinant for QoL in PD-MMP, PD-IM and PD-DM patients, the other contributors of QoL in the three subtypes were heterogeneous. These findings may prompt clinicians to target specific factors for improving QoL depending on PD subtypes., (© 2021 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)

Many estuaries have undergone severe saltwater intrusion in addition to simultaneously experiencing serious heavy metal pollution. To explore the effect of water density stratification associated with saltwater intrusion on the behaviour of heavy metals (Cr, Co, Ni, Cu, Zn, As, Pb, and Cd) in water and sediments, a field survey was conducted in a typical estuary (Modaomen). The content, distribution, and mobility of heavy metals were investigated, as well as the influence of environmental factors on their future. The results showed that Modaomen estuary was characterised by a notable variation in salinity along the estuary, presenting total freshwater upstream, high salinity stratification water in the mouth, and saltwater offshore. Dissolved metals presented a prominent gradient vertically, with 1.2-2.1 times higher in bottom water than in surface water and the highest contents in the highly-stratified bottom water. Elevated salinity and restricted mixing induced by water stratification were likely the causes of this outcome. The distribution of heavy metals in sediments was greatly governed by grain size, Fe/Mn (hydr)oxides, total organic carbon, salinity, and dissolved oxygen. Comprehensive evaluation, combined with total contents and chemical fractions of heavy metals, indicated that internal release from sediments contributed a considerable part to the higher levels of heavy metals in bottom water, particularly for Zn and Pb, which was fully consistent with their status in water body, and elevated salinity and lack of oxygen were likely the primary driving factors. During the phase-partition processes between bottom water and sediments, partitioning coefficients were markedly lower in the highly stratified zone, implying that saltwater intrusion facilitated the mobility and repartitioning processes of metals. Because of increased levels and toxicity of heavy metals in water and extended residence time during saltwater intrusion, the potential damage to the estuarine ecosystem should receive more attention., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Although eutrophication and biological invasion have caused serious harm to aquatic ecosystems, exotic and even invasive plants have been used extensively in phytoremediation water systems in China. To identify native aquatic plants with excellent water restoration potential, two representative native floating aquatic plants from Guangdong Province, namely Ludwigia adscendens (PL) and Trapa natans (PT), were selected, with Eichhornia crassipes as a control, to study their growth status, adaptability, and nutrient removal potentials in swine manure wastewater. The results demonstrated that the two native plants offered greater advantages than E. crassipes in water restoration. Within 60 days, PL and PT exhibited excellent growth statuses, and their net biomass growth rates were 539.8% and 385.9%, respectively, but the E. crassipes decayed and died with an increasing HRT (hydraulic retention time). The PL and PT could adjust the pH of the wastewater, improve the dissolved oxygen and oxidation-reduction potential, and reduce the electrical conductivity value. The removal rates of NH 4 + -N, NO 3 - -N, NO 2 - -N, total nitrogen, total phosphorus, chemical oxygen demand (COD), and Chl- a in the PL group reached 98.67%, 64.83%, 26.35%, 79.30%, 95.90%, 69.62%, and 92.23%, respectively; those in the PT group reached 99.47%, 95.83%, 85.17%, 83.73%, 88.72%, 75.06%, and 91.55%, respectively. The absorption contribution rates of total nitrogen (TN) and total phosphorus (TP) in the PL group were 40.6% and 43.5%, respectively, while those in the PT group were 36.9% and 34.5%, respectively. The results indicated that L. adscendens and T. natans are both promising aquatic plants for application to the restoration of swine manure wastewater in subtropical areas.

Phytoremediation is a potentially suitable technology for taking up large amounts of N and P during plant growth and the removal of plant material, thereby avoiding eutrophication. We compared the capacity of nine different aquatic plant species for removing total P (TP), total N (TN), and NH 4 -N from raw domestic sewage wastewater collected from a living area located in Guangzhou city, China, and different concentrations of artificial wastewater. The experiments were performed in two stages, namely screening and modification. In the screening stage, four plant species were identified from the nine grown in raw domestic sewage water for 36 days. In the modification stage, the TN and TP removal ability of different plant combinations were determined in artificial wastewater at different N/P concentrations. After having been grown in monocultures for 46 days, + -N from raw domestic sewage wastewater collected from a living area located in Guangzhou city, China, and different concentrations of artificial wastewater. The experiments were performed in two stages, namely screening and modification. In the screening stage, four plant species were identified from the nine grown in raw domestic sewage water for 36 days. In the modification stage, the TN and TP removal ability of different plant combinations were determined in artificial wastewater at different N/P concentrations. After having been grown in monocultures for 46 days, I pomoea aquatica (90.6% and 8.8%) and Salvinia natans (67.3% and 14.2%) obtained the highest TP removal efficiency in lightly and highly polluted wastewater, respectively. The combination of S. natans and Eleocharis plantagineiformis effectively removed TP and TN from lightly polluted water, suggesting that this combination is suitable for phytoremediation of eutrophic wastewater., Competing Interests: The authors declare no conflict of interest.

Background: School physical activity (PA) policy, physical education curriculum, teacher training, knowledge of physical fitness, and parental support are among the key issues underlying the declining trend of physical fitness in children and adolescents. The Chinese CHAMPS was a multi-faceted intervention program to maximize the opportunities for moderate and vigorous physical activity (MVPA), and increase physical fitness in middle school students. The purpose of the study was to test whether the levels of modification in school physical education policy and curriculum incrementally influenced the changes in cardiorespiratory fitness and other physical fitness outcomes., Methods: This 8-month study was a clustered randomized controlled trial using a 2 × 2 factorial design. The participants were 680 7th grade students (mean age = 12.66 years) enrolled in 12 middle schools that were randomly assigned to one of four treatment conditions: school physical education intervention (SPE), afterschool program intervention (ASP), SPE+ASP, and control. Targeted behaviors of the Chinese CHAMPS were the student's sedentary behavior and MVPA. The study outcomes were assessed by a test battery of physical fitness at the baseline and posttest. Sedentary behavior and MVPA were measured in randomly selected students using observations and accelerometry., Results: The terms contrasting the pooled effect of SPE, ASP, and SPE+ASP vs. Control, the pooled effect of SPE and SPE+ASP vs. ASP only, and the effect of SPE+ASP vs. ASP on CRF and other physical fitness outcomes were all significant after adjusting for covariates, supporting the study hypothesis. Process evaluation demonstrated high fidelity of the intervention in the targeted students' behaviors., Conclusions: Chinese CHAMPS demonstrated the impact of varying the amount of MVPA and vigorous physical activity (VPA) on the physical fitness in middle school students in support of the need to increase the opportunity for PA in schools and to introduce high-intensity exercises in school-based PA programs. Modification of school policy, quality of physical education curriculum, and teacher training were important moderators of the improvement in physical fitness. (Trial registration: ChiCTR-IOR-14005388, the Childhood Health; Activity and Motor Performance Study.)., Competing Interests: The authors declare that they have no competing interests.

The aim of this study is to investigate the distribution, ecological risk and quantitative source apportionment of seven heavy metals in surface sediments along a partially mixed estuary (Modaomen, China). The study area was divided into three regions based on salt-freshwater mixing: a tidal river channel, weakly mixed zone and strongly mixed zone. The concentrations of Cu, Zn, Pb, Cd, Cr and Ni were significantly higher in the weakly mixed zone, while a higher Co content was found in the tidal river channel. From enrichment factor (EF) analyses, Cd was moderate to extreme severely enriched at most stations, and other heavy metals were minor enrichments. Adverse effects on aquatic biota may occur occasionally for all seven heavy metals based on the sediment quality guidelines (SQGs). The correlations between Al and heavy metals suggested that metals in sediments were mainly attributed to anthropogenic sources. Then Positive matrix factorization (PMF) and Geostatistic method were used to quantify the heavy metal sources and determine impacted regions. A mixed source from the inner Lingding Bay and West River contributed approximately 50% of the Cu, Zn, Pb, Cr and Ni. The electroplating industry accounted for about 57% of the Cd content, and the major contaminated area was concentrated at the confluence of the West River and its tributaries. The alloy industry contributed approximately 65% of the Co, most of which was near an industrial park., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

We examined the occurrence and fate of pharmaceuticals and personal care products in surface water by combining laboratory experiments with numerical simulations. The degradation processes of two typical PPCPs (triclosan and carbamazepine) collected from the Shahe Stream were studied. Hydrolysis, biodegradation, and photolysis were the three major routes of triclosan (TCS) and carbamazepine (CBZ) degradation. A central composite design method was used to investigate the effects of related natural parameters (including pH, dissolved oxygen, salinity, temperature, light intensity, and humic acid) on the TCS and CBZ degradation processes in the laboratory. Our results showed that the main degradation pathway of CBZ and TCS was direct photolysis during the daytime and that the maximal biodegradation rates of CBZ and TCS occurred at 22 °C when the optimum temperature function was used. Based on our experimental results, the observed degradation of CBZ and TCS followed pseudo-first-order kinetics, and the degradation kinetic equations under the influence of multiple natural parameters were established with estimated average degradation rate constants of 1.2452E-7 s -1 and 3.1260E-5 s -1 for CBZ and TCS, respectively. The degradation rate constants were incorporated into a one-dimensional, simply integrated hydrodynamic and water quality model. The proposed numerical model was applied to depict the transportation and transformation of CBZ and TCS in surface water and was validated by observational data from the Shahe Stream. The results showed that our model reproduced the observed patterns of CBZ and TCS concentrations reasonably, with slight overestimations compared to the observed data; the relative errors between the simulated and the observed concentrations were 5.85%-6.82% for CBZ and -156.85%--7.18% for TCS. According to our simulation, the spatial distribution of TCS in surface water was determined by biochemical degradation processes that were most affected by temperature under natural conditions; in contrast, the distribution of CBZ was largely controlled by diffusion., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background and Purpose- Oxidized low-density lipoprotein (oxLDL) level is thought to be associated with recurrent stroke. We aimed to investigate the association between oxLDL to high-density lipoprotein (HDL) ratio and recurrent stroke in patients with minor stroke or transient ischemic attack. Methods- The study included 3019 patients with minor ischemic stroke or high-risk transient ischemic attack from the CHANCE trial (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events). Baseline oxLDL and HDL levels were measured. The primary outcome was any stroke within 90 days. The secondary outcomes included any stroke within 1 year and ischemic stroke and combined vascular events within 90 days and 1 year. The association between oxLDL/HDL and recurrent stroke was analyzed by using Cox proportional hazards. Results- Patients in the highest oxLDL/HDL quartile had a higher risk of recurrent stroke within 90 days (hazards ratio, 1.50; 95% CI, 1.08-2.08) compared with the lowest quartile after adjusting relevant confounding factors ( P=0.02). Similar results were found for secondary outcomes ( P<0.05 for all). There were no significant interaction between oxLDL/HDL and use of statins agents. Conclusions- Higher serum oxLDL/HDL level in minor stroke or transient ischemic attack was associated with increased risk of recurrent stroke in 90 days and 1 year. OxLDL/HDL may act as a powerful indicator of recurrent stroke in patients with minor stroke or transient ischemic attack. Clinical Trial Registration- URL: http://www.clinicaltrials.gov . Unique identifier: NCT00979589.