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Terrestrial carbon dioxide (CO2) flux estimates in China using atmospheric inversion method are beset with considerable uncertainties because very few atmospheric CO2 concentration measurements are available. In order to improve these estimates, nested atmospheric CO2 inversion during 2002-2008 is performed in this study using passenger aircraft-based CO2 measurements over Eurasia from the Comprehensive Observation Network for Trace gases by Airliner (CONTRAIL) project. The inversion system includes 43 regions with a focus on China, and is based on the Bayesian synthesis approach and the TM5 transport model. The terrestrial ecosystem carbon flux modeled by the Boreal Ecosystems Productivity Simulator (BEPS) model and the ocean exchange simulated by the OPA-PISCES-T model are considered as the prior fluxes. The impacts of CONTRAIL CO2 data on inverted China terrestrial carbon fluxes are quantified, the improvement of the inverted fluxes after adding CONTRAIL CO2 data are rationed against climate factors and evaluated by comparing the simulated atmospheric CO2 concentrations with three independent surface CO2 measurements in China. Results show that with the addition of CONTRAIL CO2 data, the inverted carbon sink in China increases while those in South and Southeast Asia decrease. Meanwhile, the posterior uncertainties over these regions are all reduced (2-12%). CONTRAIL CO2 data also have a large effect on the inter-annual variation of carbon sinks in China, leading to a better correlation between the carbon sink and the annual mean climate factors. Evaluations against the CO2 measurements at three sites in China also show that the CONTRAIL CO2 measurements may have improved the inversion results. [ABSTRACT FROM AUTHOR]

Due to the heterogeneous nature of the land surface, spatial scaling is an inevitable issue in the development of land models coupled with low-resolution Earth system models (ESMs) for predicting land-atmosphere interactions and carbon-climate feedbacks. In this study, a simple spatial scaling algorithm is developed to correct errors in net primary productivity (NPP) estimates made at a coarse spatial resolution based on sub-pixel information of vegetation heterogeneity and surface topography. An ecohydrological model BEPS-TerrainLab, which considers both vegetation and topographical effects on the vertical and lateral water flows and the carbon cycle, is used to simulate NPP at 30m and 1 km resolutions for a 5700 km² watershed with an elevation range from 518m to 3767m in the Qinling Mountain, Shaanxi Province, China. Assuming that the NPP simulated at 30m resolution represents the reality and that at 1 km resolution is subject to errors due to sub-pixel heterogeneity, a spatial scaling index (SSI) is developed to correct the coarse resolution NPP values pixel by pixel. The agreement between the NPP values at these two resolutions is improved considerably from R² =0.782 to R² =0.884 after the correction. The mean bias error (MBE) in NPP modeled at the 1 km resolution is reduced from 14.8 gCm-2 yr-1 to 4.8 gCm-2 yr-1 in comparison with NPP modeled at 30m resolution, where the mean NPP is 668 gCm-2 yr-1. The range of spatial variations of NPP at 30m resolution is larger than that at 1 km resolution. Land cover fraction is the most important vegetation factor to be considered in NPP spatial scaling, and slope is the most important topographical factor for NPP spatial scaling especially in mountainous areas, because of its influence on the lateral water redistribution, affecting water table, soil moisture and plant growth. Other factors including leaf area index (LAI), elevation and aspect have small and additive effects on improving the spatial scaling between these two resolutions. [ABSTRACT FROM AUTHOR]

In this study, we establish a nested atmospheric inversion system with a focus on China using the Bayes theory. The global surface is separated into 43 regions based on the 22 TransCom large regions, with 13 small regions in China. Monthly CO2 concentrations from 130 GlobalView sites and a Hong Kong site are used in this system. The core component of this system is atmospheric transport matrix, which is created using the TM5 model with a horizontal resolution of 3°x2°. The net carbon fluxes over the 43 global land and ocean regions are inverted for the period from 2002 to 2009. The inverted global terrestrial carbon sinks mainly occur in Boreal Asia, South and Southeast Asia, eastern US and southern South America (SA). Most China areas appear to be carbon sinks, with strongest carbon sinks located in Northeast China. From 2002 to 2009, the global terrestrial carbon sink has an increasing trend, with the lowest carbon sink in 2002. The inter-annual variation (IAV) of the land sinks shows remarkable correlation with the El Niño Southern Oscillation (ENSO). However, no obvious trend is found for the terrestrial carbon sinks in China. The IAVs of carbon sinks in China show strong relationship with drought and temperature. The mean global and China terrestrial carbon sinks over the period 2002-2009 are -3.15±1.48 and -0.21±0.23 PgCyr-1, respectively. The uncertainties in the posterior carbon flux of China are still very large, mostly due to the lack of CO2 measurement data in China. [ABSTRACT FROM AUTHOR]

To understand the causes of the past water cycle variations and the influence of climate variability on the streamflow, lake storage, and flood potential, we analyze the changes in streamflow and the underlying drivers in four typical watersheds (Gaosha, Meigang, Saitang, and Xiashan) within the Poyang Lake Basin, based on the meteorological observations at 79 weather stations, and datasets of stream- flow and river level at four hydrological stations for the period of 1961-2000. The contribution of different climate factors to the change in streamflow in each watershed is estimated quantitatively using the water balance equations. Results show that in each watershed, the annual streamflow exhibits an increasing trend from 1961--2000. The increases in streamflow by 4.80m³ s-1 yr-1 and 1.29m³ s-1 yr-1 at Meigang and Gaosha, respectively, are statistically significant at the 5% level. The increase in precipitation is the biggest contributor to the streamflow increment in Meigang (3.79m³ s-1 yr-1), Gaosha (1.12m-1 s-1 yr-1), and Xiashan (1.34m-1 s-1 yr-1), while the decrease in evapotranspiration is the major factor controlling the streamflow increment in Saitang (0.19m-1 s-1 yr-1). In addition, radiation and wind contribute more than actual vapor pressure and mean temperature to the changes in evapotranspiration and streamflow for the four watersheds. For revealing the possible change of streamflow due to the future climate change, we also investigate the projected precipitation and evapotranspiration from of the Coupled Model Intercomparison Project phase 3 (CMIP3) under three greenhouse gases emission scenarios (SRESA1B, SRESA2 and SRESB1) for the period of 2061-2100. When the future changes in the soil water storage changes are assumed ignorable, the streamflow shows an uptrend with the projected increases in both precipitation and evapotranspiration (except for the SRESB1 scenario in Xiashan watershed) relative to the observed mean during 1961-2000. Furthermore, the largest increase in the streamflow is found at Meigang (+4.31 %) and Xiashan (+3.84 %) under the SRESA1B scenario, while the increases will occur at Saitang (+6.87 %) and Gaosha (+5.15%) under the SRESB1 scenario. [ABSTRACT FROM AUTHOR]

Soil and atmospheric water deficits have significant influences on CO2 and energy exchanges between the atmosphere and terrestrial ecosystems. Model parameterization significantly affects the ability of a model to simulate carbon, water, and energy fluxes. In this study, an ensemble Kalman filter (EnKF) and observations of gross primary productivity (GPP) and latent heat (LE) fluxes were used to optimize model parameters significantly affecting the calculation of these fluxes for a subtropical coniferous plantation in southeastern China. The optimized parameters include the maximum carboxylation rate (Vcmax), the slope in the modified Ball-Berry model (M) and the coefficient determining the sensitivity of stomatal conductance to atmospheric water vapor deficit (D0). Optimized Vcmax and M showed larger variations than D0. Seasonal variations of Vcmax and Mwere more pronounced than the variations between the two years. Vcmax and M were associated with soil water content (SWC). During dry periods, SWC at the 20 c depth explained 61% and 64% of variations of Vcmax and M, respectively. EnKF parameter optimization improved the simulations of GPP, LE and SH, mainly during dry periods. After parameter optimization using EnKF, the variations of GPP, LE and SH explained by the model increased by 1% to 4% at half-hourly steps and by 3% to 5% at daily time steps. Further efforts are needed to differentiate the real causes of parameter variations and improve the ability of models to describe the change of stomatal conductance with net photosynthesis rate and the sensitivity of photosynthesis capacity to soil water stress under different environmental conditions. [ABSTRACT FROM AUTHOR]

Soil and atmospheric water deficits have significant influences on CO2 and energy exchanges between the atmosphere and terrestrial ecosystems. Model parameterization significantly affects the ability of a model to simulate carbon, water, and energy fluxes. In this study, an ensemble Kalman filter (EnKF) and observations of gross primary productivity (GPP) and latent heat (LE) fluxes were used to optimize model parameters significantly affecting the calculation of these fluxes for a subtropical coniferous plantation in southeastern China. The optimized parameters include the maximum carboxylation rate (Vcmax), the Ball-Berry coefficient (m) and the coefficient determining the sensitivity of stomatal conductance to atmospheric water vapor deficit D0). Optimized Vcmax and m showed larger seasonal and interannual variations than D0. Seasonal variations of Vcmax and m are more pronounced than the interannual variations. Vcmax and m are associated with soil water content (SWC). During dry periods, SWC at the 20 cm depth can explain 61% and 64% of variations of Vcmax and m, respectively. EnKF parameter optimization improves the simulations of GPP, LE and sensible heat (SH), mainly during dry periods. After parameter optimization using EnKF, the variations of GPP, LE and SH explained by the model increased by 1% to 4% at half-hourly steps and by 3% to 5% at daily time steps. Efforts are needed to develop algorithms that can properly describe the variations of these parameters under different environmental conditions. [ABSTRACT FROM AUTHOR]

Solar-induced chlorophyll fluorescence (SIF) serves as a valuable proxy for photosynthesis. The TROPOspheric Monitoring Instrument (TROPOMI) aboard the Copernicus Sentinel-5P mission offers nearly global coverage with a fine spectral resolution for reliable SIF retrieval. However, the present satellite-derived SIF datasets are accessible only at coarse spatial resolutions, constraining its applications at fine scales. Here, we utilized a weighted stacking algorithm to generate a high spatial resolution SIF dataset (500 m, 8-day) in China (HCSIF) from 2000 to 2022 from the TROPOMI with a spatial resolution at a nadir of 3.5 km by 5.6-7 km. Our algorithm demonstrated high accuracy on validation datasets (R 2  = 0.87, RMSE = 0.057 mW/m 2 /nm/sr). The HCSIF dataset was evaluated against OCO-2 SIF, GOME-2 SIF tower-based measurements of SIF, and gross primary productivity (GPP) from flux towers. We expect this dataset can potentially advance the understanding of fine-scale terrestrial ecological processes, allowing for monitoring of ecosystem biodiversity and precise assessment of crop health, productivity, and stress levels in the long term., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Importance: Recurrence remains a challenge after ablation of outflow tract premature ventricular contractions (OT-PVCs). Although adding additional lesions next to the index effective ablation site is sometimes performed to reinforce the ablation, it remains uncertain whether this approach is effective., Objective: To test the hypothesis that additional ablation lesions would reduce the recurrence rate compared with single-point ablation at the index effective site for the ablation of OT-PVCs., Design, Setting, and Participants: This study was a multicenter, prospective, randomized clinical trial. Patients receiving their first catheter ablation for OT-PVCs were enrolled from 18 hospitals in China between October 2021 and February 2023. Scheduled follow-up duration was 3 months after the procedure., Intervention: After identifying the target point and eliminating the PVC by a single-point ablation, patients were randomized 1:1 into an additional ablation group or a control group., Main Outcomes and Measures: The primary end point of the study was freedom from PVC recurrence (≥80% reduction of PVC burden, which is the number of PVCs in 24 hours/total heartbeats in 24 hours × 100%) from baseline to 3 months postprocedure., Results: Of 308 patients enrolled in the study, 286 (mean [SD] age, 49.2 [14.6] years; 173 female [60.5%]) were randomized to the additional ablation or the control group. The additional ablation group had a mean (SD) of 6.3 (1.1) radiofrequency applications, whereas the control group (single-point ablation group) had a mean (SD) of 1 (0) radiofrequency application. After a median (IQR) follow-up of 3.2 (0) months, the rate of freedom from PVCs was significantly higher in the additional ablation group (139 of 142 [97.9%]) compared with the control group (115 of 139 [82.7%]; P < .001). Patients in the additional ablation group also had a more substantial reduction in PVC burden than the control group (mean [SD] reduction, 23.0% [10.5%] vs 19.0% [10.4%]; P = .002). There were no severe periprocedural complications in either group., Conclusions and Relevance: This randomized clinical trial showed a benefit of additional ablation in reducing the recurrence of OT-PVCs compared with the single-point ablation strategy, without increased complication risk. Additional ablations surrounding the index effective ablation point should be considered in OT-PVC ablation., Trial Registration: Chinese Clinical Trials Registry Identifier: ChiCTR2200055340.

Background: Ventricular tachycardia (VT) is the primary cause of sudden cardiac death in patients with hypertrophic cardiomyopathy (HCM). However, the strategy for VT treatment in HCM patients remains unclear. This study is aimed to compare the effectiveness of catheter ablation versus antiarrhythmic drug (AAD) therapy for sustained VT in patients with HCM., Methods: A total of 28 HCM patients with sustained VT at 4 different centers between December 2012 and December 2021 were enrolled. Twelve underwent catheter ablation (ablation group) and sixteen received AAD therapy (AAD group). The primary outcome was VT recurrence during follow-up., Results: Baseline characteristics were comparable between two groups. After a mean follow-up of 31.4 ± 17.5 months, the primary outcome occurred in 35.7% of the ablation group and 90.6% of the AAD group (hazard ratio [HR], 0.29 [95%CI, 0.10-0.89]; P = 0.021). No differences in hospital admission due to cardiovascular cause (25.0% vs. 71.0%; P = 0.138) and cardiovascular cause-related mortality/heart transplantation (9.1% vs. 50.6%; P = 0.551) were observed. However, there was a significant reduction in the composite endpoint of VT recurrence, hospital admission due to cardiovascular cause, cardiovascular cause-related mortality, or heart transplantation in ablation group as compared to that of AAD group (42.9% vs. 93.7%; HR, 0.34 [95% CI, 0.12-0.95]; P = 0.029)., Conclusions: In HCM patients with sustained VT, catheter ablation reduced the VT recurrence, and the composite endpoint of VT recurrence, hospital admission due to cardiovascular cause, cardiovascular cause-related mortality, or heart transplantation as compared to AAD., (© 2024. The Author(s).)

Revegetation is effective in improving soil quality in ecologically fragile areas. However, little is known about the impact of diverse phytomanagement strategies of tailings on soil quality and ecological security in erosion-prone areas. We investigated the water stability, soil aggregate nutrients, and the risk of heavy metal contamination of abandoned tailings under phytomanagement and in adjacent bare land on the Loess Plateau. The results showed that phytomanagement significantly enhanced soil aggregate stability, as demonstrated by higher contents of soil organic carbon (SOC), glomalin-related soil protein (GRSP), aromatic-C, and alkene-C in macro-aggregates. The pollution load index (PLI) and ecological risk index (RI) of soil heavy metals were lower in shrub/herbaceous mixed forests than in natural grasslands and planted forests. The risk of heavy metal contamination was higher in macro-aggregates (>0.25 mm) than in micro-aggregates (<0.25 mm) and was significantly and positively correlated with the SOC and GRSP contents of the aggregates. Our study demonstrates that soil aggregate quality is closely related to the fate of heavy metals. Diversified tailing revegetation measures can improve soil quality and ensure ecological security., 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.)

Competing Interests: The authors declare no conflicts of interest.

Disability weights are crucial for quantifying health loss associated with non-fatal outcomes and were not well assessed in different countries, especially for specific cancer. Therefore, this study aimed to identify disability weights with a focus on specific cancer in a large Chinese population. Two types of web surveys were conducted, and 254 health states, including 30 new states for specific cancer, were investigated using paired comparison methods. The years lived with disability (YLDs) of cancer were calculated as the sum of the prevalence of each sequela of cancer multiplied by its relative disability weight. In total, 44,069 participants were eligible for the disability weights study. The disability weights of 254 health states were estimated. Among those, the disability weights of 18 specific cancer types varied greatly at diagnosis and primary treatment stage, with the value ranging from 0.619 (95% uncertainty interval (UI) 0.606-0.632) for brain cancer to 0.167 (95% UI 0.158-0.176) for oropharyngeal cancer. The discrepancy in YLDs calculated by different disability weights was high, and the largest gap for all cancer combined was approximately 30.14%. When calculated using the cancer-specific disability weights, a total of 1,967,830 (95% UI 1,928,880-2,008,060) YLDs of cancer were recorded in China. The disability weights of cancer varied greatly among cancer types and populations, which had considerable influence on the estimation of the disease burden. Cancer-specific disability weights could provide a more accurate evaluation of the cancer burden., Competing Interests: Conflict of interest The authors declare that they have no conflict of interest., (Copyright © 2023. Published by Elsevier B.V.)

Largely due to population ageing, the cancer burden from older people has been rising, which imposed considerable pressure on current Chinese healthcare system. We provide comprehensive information about cancer burden of Chinese older people based on the most recent data from National Central Cancer Registry of China. The logarithmic linear regression was used to project the current cancer burden in 2022, and Joinpoint regression was used for temporal trend analysis from 2000 to 2017. We also estimated cancer statistics of older people in the US, Japan and the Republic of Korea for comparisons. It is estimated that 2.79 million cases and 1.94 million deaths occur for Chinese older people, representing 55.8% and 68.2% of cases and deaths in all population in 2022. The overall cancer incidence rate gradually increased among older women, while the mortality rates declined for both sexes. Notably, approximately 10.0% of all cases and 17.7% of all deaths are from people aged over 80 years, and cancer incidence and mortality in this age group showed upward trends for women. Lung cancer and digestive cancers are the leading cancer types for Chinese older people. Compared with other countries, China has lower incidence rates but higher mortality rates for older people. The rapidly growing burden of prostate cancer, breast cancer, colorectal cancer, and declines in esophageal cancer, stomach cancer, and liver cancer among older people indicate the cancer pattern in China is being in a transition stage to that in developed countries. Our findings imply that it should be the national health priority to meet the growing demands for cancer diagnosis, treatment and care services from the older people as the rapid population ageing in next few decades., (© 2022. Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature.)

To investigate the international development status and hot trends in the field of environmental security management in recent years, the published the environmental security management literature from 1997 to 2021, which was retrieved from Web of Science, with VOSviewer as the main and CiteSpace as the auxiliary, through the cooperation network of authors, scientific research institutions, and countries. The keywords were visualized by clustering, time zone analysis, and burst analysis. A total of 7596 articles were retrieved, forming six main clustering labels, including 28,144 authors. The research hotspots are from the fields of personal health, society, agriculture, ecological environment, energy, and sustainable development, as well as the development of internet environmental safety management, such as big data, Bayesian networks, and conceptual frameworks. Through cluster analysis, the cooperation of major research teams and scientific research institutions and the cooperation and development between countries were analyzed. The cooperation between scientific research institutions in various countries is relatively close. The United States currently occupies a dominant and authoritative position in this field. China has cooperated more closely with the United States, Britain, Australia, and India.

Source-tagged source apportionment (SA) has advantages for quantifying the contribution of various source regions and categories to PM 2.5 ; however, it is highly affected by uncertainty in the emission inventory. In this study, we used a Regional multi-Air Pollutant Assimilation System (RAPAS) to optimize daily SO 2 , NO x and primary PM 2.5 (PPM 2.5 ) emissions in the Yangtze River Delta (YRD) in December 2016 by assimilating hourly in-situ measurements. The CMAQ-ISAM model was implemented with prior and posterior emissions respectively to investigate the impacts of optimizing emissions on PM 2.5 SA in the YRD megalopolis (YRDM) and three megacities of Shanghai, Nanjing, and Hangzhou in the YRDM. The results showed that RAPAS significantly improved the simulations and reduced the emission uncertainties of the different pollutants. Compared with prior emissions, the posterior emissions in the YRD decreased by 13% and 11% for SO 2 and NO x respectively, and increased by 24% for PPM 2.5 . Compared with SA using prior emissions, the contributions from Hangzhou, northern Zhejiang, and areas outside of the YRD to the YRDM increased. The local contributions from the YRDM, Nanjing and Shanghai decreased by 1.8%, 9.7%, and 2.3%, respectively, whereas that of Hangzhou increased by 5.6%. The changes in the daily local contributions caused by optimizing emissions ranged from -18.0% to 23.6%. Generally, under stable weather conditions, the local contribution changed the most, whereas under unstable weather conditions, the contribution from upwind areas changed significantly. Overall, with optimized emissions, we found in Nanjing, Shanghai, and Hangzhou, local emissions contributed 18.2%, 39.6% and 36.8% of their PM 2.5 concentrations, respectively; long-range transport from outside the YRDM contributed 59.2%, 48.1%, and 48.2%, respectively. This study emphasizes the importance of improving emission estimations for source-tagged SA and provides more reliable SA results for the main cities in the YRD, which will contribute to pollution control in these regions., 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.)

Net primary productivity (NPP) has been widely used as the indicator of vegetation function and exhibits large spatial and temporal variations caused by numerous factors. Northwest China (NWC) is one of the driest regions in China, and water supply is the key determinant of NPP here. However, studies on the effects of water stress on NPP in NWC at the regional scale are still relatively lacking. Thus, in this study, based on a set of Moderate-Resolution Imaging Spectroradiometer (MODIS) NPP and evapotranspiration (ET) datasets, we quantified the response of NPP to water stress, which is indicated by crop water stress index (CWSI). Regional average of annual NPP in NWC showed an increasing trend during the study period, at a rate of 0.84 g C m -2 yr -1 . At the province level, the NPP increase rates increased in the order of Ningxia (7.7%), Shaanxi (6.5%), Gansu (4.5%), Qinghai (3.8%), and Xinjiang (1.7%). NPP was negatively correlated with CWSI (p<0.05) in 73% of areas, indicating the key role of water stress in constraining NPP over this arid region. The effect of water stress on NPP changes with elevation. Water stress has the strongest negative impact on NPP in areas with elevations around 2000 m. In elevations above 5000 m, NPP is not limited by water stress, mostly positively correlated with CWSI. Our findings further clarify the importance of water stress in dryland ecosystems, while highlighting that elevation gradients can significantly affect the correlation between NPP and water stress., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Dengue fever is a mosquito-borne febrile illness. Southeast Asia experienced severe dengue outbreaks in 2019, and over 1000 cases had been reported in Jiangxi, a previously known low-epidemic region in China. However, the emergence of a dengue virus epidemic in a non-epidemic region remains unclear., Methods: We enrolled 154 dengue fever patients from four hospitals in Jiangxi, from April 2019 to September 2019. Real-time PCR, NS1 antigen rapid test, and IgM, IgG tests were performed, and 14 samples were outsourced to be sequenced metagenomically., Results: Among the 154 cases, 42 were identified as imported and most of them returned from Cambodia. A total of 113 blood samples were obtained and 106 were identified as DENV-1, two as DENV-2, and five were negative through RT-PCR. All DENV-1 strains sequenced in this study were all classified to one cluster and owned a high similarity with a Cambodia strain isolated in 2019. The evolutionary relationships of amino acid were consistent with that of nucleotide genome result. The sequence-based findings of Jiangxi strains were consistent with epidemiological investigation., Conclusion: Epidemiological analysis demonstrated that the emergence of dengue cases led to autochthonous transmission in several cities in Jiangxi, a low-epidemic region before. This study emphasized future prevention and control of dengue fever in both epidemic and non-epidemic regions., 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 © 2021 Zhang, Chen, Wang, Wang, Wu, Zhou, Wang, Luo, Tu, Chen, Huang, Ju, Peng, Rao, Wang, Jiang, Ai and Zhang.)

Background and Purpose: Complete P wave disappearance (CPWD) in patients without atrial fibrillation is an uncommon clinical phenomenon. We aimed to study the relationship between CPWD and thromboembolism., Methods: Between July 2007 and December 2018, consecutive patients with CPWD on surface ECG and 24-hour Holter recording were recruited into the study from 4 centers in China. All recruited patients underwent transesophageal echocardiography or cardiac computed tomography to screen for atrial thrombus. Atrial electrical activity and scar were assessed by electrophysiological study (EPS) and 3-dimensional electroanatomic mapping. Cardiac structure and function were assessed by multimodality cardiac imaging., Results: Twenty-three consecutive patients (8 male; mean age 48.5±14.7 years) with CPWD were included. Only 3 patients demonstrated complete atrial electrical silence with atrial noncapture. Thirteen patients who had invasive atrial endocardial mapping demonstrated extensive scar. Pulse-wave mitral inflow Doppler demonstrated absent and dampened A waves in 18 and 5 patients, respectively. Pulse-wave tricuspid inflow Doppler showed absent and dampened A waves in 19 and 4 patients, respectively. Upon recruitment, 8 patients had previous stroke and 3 patients had atrial thrombus. Warfarin was prescribed to all patients. During median follow-up of 42.0 months, 2 patients developed massive ischemic stroke due to warfarin discontinuation., Conclusions: Our study suggested that CPWD reflects extensive atrial electrical silence and significantly impaired atrial mechanical function. It was strongly associated with thromboembolism and the clinical triad of CPWD-atrial paralysis-stroke was proposed. Anticoagulation should be recommended in such patients.

This study analyzed the epidemiological and clinical features of dengue fever in Zhangshu, Jiangxi Province, in 2019 and provided evidence for the diagnosis, treatment, prevention, and control of dengue fever. A total of 718 dengue fever patients in Zhangshu in 2019 were involved. ELISA and qRT-PCR were used for pathogenic detection of dengue virus. Multiple adjuvant therapies were applied, and the condition of patients after treatment was examined. Patients were between the ages of 0.75 and 92 years old, and all of them had a fever. A total of 519 cases had fatigue, and 413 cases had generalized myalgia and bone ache; 356 cases had dry mouth, 289 cases had bitter taste, and 167 cases felt dry and bitter taste; 279 cases had rash, and 93 cases had pruritus; 587 cases had decreased leukocyte, among which, 7 cases had leukocyte lower than 1 × 10 [9]/L; 380 cases had a low platelet count, and the platelet count of 29 cases was lower than 50 × 10 [9]/L; 488 cases had increased aspartic transaminase, and 460 cases had increased alanine aminotransferase; 5 cases had a severe disease. It proved that the majority of dengue fever sufferers were adults, with the main clinical features being fever and rash and the chief injured organs being the blood system, liver, heart, and gastrointestinal tract. Besides, over 40% of patients had dry and bitter taste, and 12 cases had alopecia after discharge. It indicates that the incidence of dengue fever in Zhangshu is closely related to the sudden population flow and imported cases.

Heavy metal contaminates have become a significant threat to soil ecosystems due to their chronicity and universality in soil. Soil microbial metabolism plays a vital role in biogeochemical cycles and soil functions. However, the response of microbial metabolism to heavy metal contamination in soil remains elusive despite potentially offering important insight into the health and ecological consequences of soil ecosystems under such contamination. This study used extracellular enzyme stoichiometry models to identify the response of microbial metabolism to various heavy metal contaminants, while also revealing potential implications of heavy metal contaminates in soil ecosystems. Results showed that microbial metabolism was restricted by soil carbon (C) and phosphorus (P) within a heavy metal polluted area in Northwest China. Heavy metal stress significantly increased microbial C limitation while decreasing microbial P limitation. However, microbial C and P limitations both responded consistently to different heavy metals (i.e., Cd, Pb, Zn, and Cu). Heavy metals had the greatest effect on microbial C limitation (i.e., 0.720 of the total effects) compared to other soil properties, and soil with the lowest heavy metal concentration exhibited the lowest microbial C limitation, and vice versa. These results indicated that microbial metabolic limitation can robustly and sensitively reflect the degree of heavy metals pollution in soil. Additionally, increased microbial C limitation caused by heavy metal contaminants could potentially escalate C release by promoting soil C decomposition as well as increasing investments in enzyme production and the maintenance of metabolic processes. Consequently, potential C loss induced by heavy metal pollution on soil ecosystems may be extensive and significant. Generally, our results suggest the usefulness of extracellular enzyme stoichiometry as a new method from which to evaluate heavy metal soil pollution, while microbial metabolic limitation could potentially be a promising indicator., 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 © 2020 Elsevier B.V. All rights reserved.)

BACKGROUND Normothermic machine perfusion (NMP) can provide access to evaluate and resuscitate high-risk donor livers before transplantation. The purpose of this study was to determine the efficacy of NMP in preservation and assessment of extended-criteria donor (ECD) livers in China. CASE REPORT From September 2018 to March 2019, 4 liver grafts from 3 transplant center defined as ECD were subjected to NMP, and then were transplanted successfully. During perfusion, perfusion parameters such as vascular flow, glucose level, lactate clearance, and bile production/composition were recorded to assess graft viability. All recipients were followed up 6 months after transplantation. CONCLUSIONS NMP provides a potential tool for preservation and assessment of ECD livers in China.

Background: Asymptomatic cerebral emboli (ACE) are commonly seen on cerebral magnetic resonance imaging (MRI) after atrial fibrillation ablation, but the incidence in previous studies varies widely. No data exists to compare the effects of different diffusion-weighted imaging (DWI) settings on detecting ablation-related ACE. This self-control study sought to compare the incidence and characteristics of ablation-related ACE between high-resolution DWI and conventional DWI., Methods: A total of 55 consecutive patients referred for atrial fibrillation ablation between December 2017 and September 2018 were enrolled. Patients underwent high-resolution DWI 1 day before ablation and repeated high-resolution DWI and conventional DWI within 48 hours post-ablation. The incidence, number, size, and location of ACE were compared between 2 DWI settings in the same patients., Results: The high-resolution DWI revealed a higher incidence of acute ACE compared with conventional DWI (67.3% versus 41.8% of patients, P <0.001) and significantly more ACE (106 versus 45 lesions, P =0.001). For ACE seen on both scans, the size measured by high-resolution DWI was larger (5.42 versus 4.21 mm, P <0.001). No patients had any impaired neurocognitive performance during follow-up. Impaired left ventricular ejection fraction ( P =0.012) and low intraoperative activated clotting time ( P =0.009) level were associated with the occurrence of ACE in a multivariate analysis., Conclusions: High-resolution DWI revealed a higher incidence and greater details of post-ablation ACE in patients with atrial fibrillation. MRI settings significantly impact the detection of ACE and should be considered when comparing incidence rates of ACE among different studies., Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01761188.

The paddy rice fields act as an important anthropogenic source of methane (CH 4 ) to the atmosphere. The study of pattern, magnitude, and environmental controls of CH 4 emissions are still insufficient due to limited measurements and understand of underlying drivers for variations of CH 4 fluxes at different temporal scales. In this study, CH 4 fluxes from a rice-wheat rotation agroecosystem in eastern China were continuously measured using the eddy covariance technique. The diurnal and seasonal variations of CH 4 flux and potential controlling factors in 2016 were analyzed using wavelet coherence, conditional Granger causality, correlation analysis and path analysis methods. CH 4 fluxes showed distinguishable diurnal variations with single peaks during 13: 00-16: 00 local time. At the diurnal timescale, gross primary productivity (GPP) regulates CH 4 fluxes after accounting for the effects of latent heat flux (LE), air temperature (TA), and soil temperature (TS) on CH 4 fluxes. LE mirrored the diurnal pattern of CH 4 fluxes when the effects of TA and TS on CH 4 fluxes were considered. Daily CH 4 fluxes exhibited large seasonal variations, with the largest daily CH 4 flux of 1191.78 mg C-CH 4  m -2  d -1 on 29 July 2016. The daily CH 4 fluxes were continuously low in the growing season of wheat, and sharply increased from very low values in late June to peaks in late July and early August, and then gradually decreased to low values at the end of the rice growing season in late November and early December. Correlation analysis and path analysis showed that seasonal variations of soil temperature, air temperature, and GPP had strong effects on daily CH 4 fluxes during pre-panicle initiation of the rice growing season, while soil temperature and leaf area index (LAI) had very strong effects on daily CH 4 fluxes during the post-panicle initiation stage. The total of CH 4 fluxes from the rice-wheat rotation agroecosystem into the atmosphere amounted to 58.08 ± 9.87 g C m -2 in 2016, and the annual net carbon (C) budget and greenhouse gas (GHG) budget were 163.50 ± 9.87 g C m -2 and 2322.53 ± 329.00 g CO 2 eq m -2 , respectively. This study represents a comprehensive assessment of fluxes and drivers of CH 4 from a rice-wheat rotation agroecosystem at different timescales. Additionally, the consecutive data of CH 4 emission in this region will also useful for model calibration and validation., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: This study will systematically evaluate the psychological effects of advanced care (AC) on patients who received endoscopic gastric cancer resection (EGCR)., Methods: This study will search the following databases of Cochrane Library, Pubmed, EMBASE, Web of Science, WANGFANG, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure from inception to the present with no language limitation. All randomized controlled trials on assessing the psychological effects of AC for patients with EGCR will be included., Results: This study will explore the psychological effects of AC on EGCR by assessing depression, anxiety, health-related quality of life, and adverse events., Conclusion: This study will summarize recent evidence for the psychological effects of AC on EGCR., Prospero Registration Number: PROSPERO CRD42019139868.

Background and Objectives: Danhong injection is the most commonly prescribed adjuvant drug applied for the treatment of cardiovascular and cerebrovascular diseases in China. Ceftriaxone is usually prescribed along with Danhong injection to elderly patients with complications. However, the pharmacokinetic interactions between these two medications have not been investigated. The aim of this study was to investigate whether Danhong injection influences the pharmacokinetic profile of ceftriaxone in old rats when these two medications are used in combination., Methods: The animal experiment protocol was designed according to the clinical data. Ten-month-old male Sprague-Dawley (SD) rats were dosed with ceftriaxone through intravenous administration for 1 or 7 days in the presence or absence of Danhong injection. The combinations were divided into 1-day, 7-day, and 14-day combined-treatment groups in which Danhong injection was administered for 1, 7, or 14 days and ceftriaxone was given for 1, 7, or 7 days, respectively. The plasma concentration of ceftriaxone was determined by ultrahigh performance liquid chromatography coupled with triple-quadrupole mass spectrometry (UHPLC-TQ-MS) on a BEH C18 column with a mobile phase consisting of acetonitrile and 0.4% formic acid-water. The chromatographic method was validated and found to be simple, rapid, and stable., Results: Danhong injection significantly increased the plasma clearance of and decreased systemic exposure to ceftriaxone. In the 1-day combined-treatment group, the plasma clearance of ceftriaxone increased by 52.69%, and the area under the concentration-time curve (AUC) of ceftriaxone was decreased by 32.54% (P < 0.01). In the 7-day combined-treatment group, the rate of plasma clearance increased by 52.49% and the area under the concentration-time curve decreased by 31.15% (P < 0.01). For the 14-day combined-treatment group, the plasma clearance of ceftriaxone increased by 26.73%, and the area under the concentration-time curve decreased by 21.44% (P < 0.05)., Conclusions: In old male rats, systemic exposure to ceftriaxone decreased when used concomitantly with Danhong injection, which may be because Danhong injection increased the plasma clearance of ceftriaxone. Further investigations should be carried out to clarify the mechanism for the influence of Danhong injection on the pharmacokinetics of ceftriaxone.

Grassland, as an important part of land cover, plays an important role in the global carbon cycle and carbon balance. Net ecosystem productivity (NEP) is a key indicator of the carbon cycle process and an important factor in assessing ecosystem security and maintaining ecosystem balance. In this paper, Boreal Ecosystem Productivity Simulator (BEPS) combining meteorological data, leaf area index, and land cover type data were used to simulate the grassland NEP of China from 1979 to 2008. This model was also used to analyze the responses to changes in climate factors, interannual variation in carbon conversion efficiency, drought stress coefficient, and water use efficiency of grassland in China. Results showed that from 1979 to 2008, the mean annual grassland NEP was 13.6 g C/m 2 with weak carbon sinks. The grassland NEP distribution increased from northwest to southeast across China. Regions with NEP of > 0 (C sink) accounted for 73.1% of the total grassland area of China. The total C sequestration reached 26.6 Tg yearly, and grassland NEP was positive from 1979 to 2008. The annual changing characteristics were analyzed. Grassland NEP was positive with carbon sink from June to September, which was negative with carbon source in the remaining months. The carbon conversion efficiency and water use efficiency of the grassland increased significantly within 30 years. NEP showed positive correlation with precipitation (accounting for 74.2% of the total grassland area was positively correlated) but weakly positive correlation with temperature (50.2% of the case). Furthermore, significant positive correlation was found between grassland NEP and precipitation, especially in northeastern and central Inner Mongolia, northern Tianshan of Xinjiang, southwestern Tibet, and southern Qinghai Lake.

Objective: To understand the current situation of soil-transmitted nematode infections and influencing factors of pupils in rural areas of Yi Ethnicity in Butuo County, Sichuan Province, so as to provide the evidence for the prevention and control of soil-transmitted nematode infections., Methods: In 2016, the pupils of 2 villages in Butuo County were selected by the multi-stage random sampling method, and the relevant information was obtained by questionnaires, including social demographic information, diet and hygiene habits and acknowledge of parasitic disease prevention. The soil-transmitted nematode infections were examined by Kato-Katz technique. The results were statistically analyzed by the single factor analysis and multivariate logistic regression methods., Results: A total of 160 pupils were investigated in this survey. The soil-transmitted nematodes included Ascaris lumbricoides , Trichuris trichiura and hookworm. The overall infection rate was 89.38%, and the multi-infection rate was 54.55%. The infection rates of A. lumbricoides and T. trichiura were higher. The infection densities were mild (75.68%) or moderate (22.97%). The logistic regression analysis showed that the protective factor of soil-transmitted nematode infections was the knowledge about correct diet and health habits notified by teachers ( OR = 0.67), but the risk factor was drinking unboiled water ( OR = 19.26)., Conclusions: The infection rate of nematodes is still high in the pupils in rural areas of Yi Ethnicity in Butuo County, Sichuan Province. Therefore, we should strengthen the prevention and control of soil-transmitted nematode infections, especially A. lumbricoides and T. trichiura infections, and mostly develop the teachers'function in health education.

Background: Paediatric liver allografts sometimes are allocated to adult recipients when there are no suitable paediatric recipients on the waiting list. However, debate exits regarding the reported outcomes of liver transplants using such small grafts., Methods: Records from adult patients undergoing liver transplantation between February 2010 and January 2016 who received whole grafts from paediatric (≤ 13 years) donors or ideal deceased adult (18-35 years) donors were reviewed. Patient and graft survival, post-transplant liver function, and complications between the two groups were compared., Results: The baseline characteristics were comparable, except that the paediatric donor allografts had smaller size. The 3-month, 1-year, and 3-year rates of patient survival were 91.3%, 85.2%, and 85.2% in the paediatric donor group and 93.4%, 88.9%, and 85.0% in the adult donor group (P = 0.947), respectively. One patient receiving a paediatric allograft developed small-for-size liver syndrome post-transplantation. There was no difference in primary non-function, early allograft dysfunction, biliary complications, vascular complications, or infection between the two groups., Conclusion: Our study indicates that using paediatric donor livers in well-selected adult recipients is a safe procedure, considering there was no suitable paediatric recipient. However, the risk of portal hyperperfusion should be considered in clinical cases such as size-mismatched transplants., (Copyright © 2018. Published by Elsevier Masson SAS.)

Hantavirus is the causative agent of hemorrhagic fever with renal syndrome (HFRS). Heilongjiang Province is experiencing an epidemic of HFRS, the main causative agent is a variant of hantavirus called Seoul virus (SEOV). In this study, the entire genome of one SEOV, the DN2 strain, was sequenced and analyzed. The alignment analysis of the sequences indicated that the DN2 strain shares the highest homology with the SEOV-LYO852 strain. The nucleotide identity is 97.6% for the S segment, 97.7% for the M segment, and 98.0% for the L segment. The corresponding amino acid sequence homologies are 99.1%, 98.9% and 99.8%. The phylogenetic analysis of the segments suggests that the DN2 strain has a high genetic relationship with SEOV strains and no genetic recombination occurs.

Although selenium, which is a necessary trace element for the human body, has been considered to be beneficial to the cardiovascular system and helpful to lower blood pressure, more and more evidence shows that high amounts of selenium are a risk factor for hypertension. A random multistage sampling which included the cluster method was performed; a total of 9076 urban and rural residents between 18 and 80 years old in the Shandong province of China were investigated by questionnaire, physical examination, and laboratory tests. The prevalence of hypertension was 42.1% in males and 35.3% in females. The mean (standard deviation) selenium concentration was 124.68 (36.32) μg/l in males and 119.54 (31.88) μg/l in females. After adjusting for potential confounders, logistic regression analysis showed that the highest selenium levels were associated with a risk of hypertension (OR = 1.192; 95% CI 1.009-1.407) in females, while there was no significant difference in males (OR = 1.043; 95% CI 0.864-1.259). Our findings suggest that high selenium levels in females are more likely to increase the risk of hypertension compared to similar levels in males. More attention should be paid to the metabolic mechanisms and physiological effects of selenium in females.

Background: As the key component of glutathione peroxidase with unique antioxidant properties, selenium has been considered to play an important part on lipid metabolism. However, the associations of serum selenium concentrations with lipid concentrations and dyslipidemia are still controversial., Methods: We analyzed cross-sectional data including serum selenium levels, lipid concentrations and other related indexes of 8198 rural Chinese. Serum selenium was measured by inductively coupled plasma mass spectrometry, and total cholesterol (TC), triglyceride (TG), high density lipoprotein-cholesterol (HDL-c) and low density lipoprotein-cholesterol (LDL-c) of serum were measured with kits., Results: Overall, mean serum selenium was 120 μg/l. Multivariate liner regression revealed that selenium concentrations were positively correlated with TC (P < 0.001), HDL-c (P < 0.001), TG (P < 0.001) and LDL-c (P < 0.001). Compared with the lowest quintile of serum selenium, participants in quintile 3, 4 and 5 had higher risks of High-TC dyslipidemia (P ≤ 0.02) and High-LDLC dyslipidemia (P < 0.02) after adjusting for covariates. In the stratified analyses, we found that the selenium-dyslipidemia associations were significantly stronger in post-menopausal women (OR: 2.72; 95% CI: 1.97, 4.17) and diabetics (OR: 9.40; 95% CI: 3.02, 29.26)., Conclusion: Elevated serum selenium levels were correlated with the increased concentrations of TC, LDL-c, HDL-c and TG, and increased the risk of High-TC and High-LDLC dyslipidemia among rural Chinese. However, the real associations between serum selenium and lipid profile should be verified in specifically designed randomized trials in future., (Copyright © 2017 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

We previously reported that serum N 1 -methylnicotinamide (me-NAM), an indicator of nicotinamide N-methyltransferase (NNMT) activity, was associated with obesity, diabetes, and coronary artery disease in Chinese patients. However, whether NNMT might play a role in the development of heart failure remains to be elucidated. In this study, the associations between levels of serum me-NAM and left ventricular structure and function were investigated in Chinese patients. Serum me-NAM was measured by liquid chromatography-mass spectrometry in 265 subjects. M-mode, 2-dimensional and Doppler echocardiography were performed with the GE Vivid E9 system to assess left ventricular structure and function. Of note, the participants in the top tertile of me-NAM had the lowest left ventricular ejection fraction (LVEF), preload recruitable stroke work (PRSW), and highest prevalence of left ventricular systolic dysfunction (LVSD). Serum me-NAM was negatively correlated with LVEF and PRSW before and after adjusted for potential confounding variables (P ≤ 0.02). In multiple logistic regression analyses, the subjects in the top tertile of me-NAM had highest risks for LVSD (OR 6.80; 95% CI 1.26-36.72; P = 0.026), which was also observed in continuous analyses (OR 9.48; 95% CI 1.41-63.48; P = 0.02). In conclusion, serum me-NAM is negatively associated with LVEF and PRSW and accordingly positively associated with the prevalence of LVSD in Chinese patients.

There is little information on the association between baseline non-structural protein (NS) 5b resistance-associated variants (RAVs) and treatment failure in hepatitis C patients. This study examined the frequencies of natural hepatitis C virus (HCV) NS5B resistance-associated variants (RAVs) in an Asian cohort. Samples from Asian HCV patients enrolled between October 2009 and September 2014 were analyzed for NS5B RAVs within the region from amino acid 230 to 371. Serum samples were tested by PCR genotyping, with sequence alignment performed using the neighbor-joining method. NS5B was detected by Sanger sequencing followed by Geno2pheno analysis. NS5B RAVs were detected in 80.52% (1199/1489) of patients; 68.4% (1019/1489) and 79.7% (1186/1489) were associated with resistance to sofosbuvir (SOF) and dasabuvir (DSV), respectively. These RAVs were present in 95% (1004/1058) of genotype 1b patients. When genotypes 1b and 2a were compared, SOF-associated RAVs were detected at a higher frequency in genotype 1b (94.8% [1004/1058] vs. 2.9% [9/309]; χ 2 = 1054.433, P < 0.001), C316H/N was more common in genotype 1b (94.7% [1002/1058] vs. 0% [0/309]; χ 2 = 1096.014, P < 0.001), M289F/L/I/W/V had a higher frequency in genotype 2a (0.7% [7/309] vs. 2.3% [7/1058]; χ 2 = 4.589, P = 0.032), DSV-associated RAVs were most often found in genotype 1b (95.0% [1005/1058] vs. 40.1% 124/309]; χ 2 = 500.577, P < 0.001), and frequency of C316Y/H/N/W was higher in genotype 1b (94.7% [1002/1058] vs. 0% [0/309]; χ 2 = 1096.014, P < 0.001). In conclusion, baseline SOF and DSV RAVs are common in Asian HCV patients and predominantly occur in genotype 1b.

Background: Diarrheagenic Escherichia coli (DEC) is a major cause of bacterial gastroenteritis in children. Also, antibiotic resistance among DEC is becoming a critical area of concern in clinical settings., Methods: This study was conducted in 4 hospitals in Shanghai from June 2012 to October 2013. DEC isolates from stool samples of patients with diarrhea were examined to determine their antimicrobial susceptibilities and presence of virulence genes, in order to identify high risk clones., Results: A total of 735 (10.2%) DEC isolates were identified from 7204 stool samples from patients with diarrhea, including 374 enteropathogenic E. coli, 318 enterotoxigenic E. coli, 36 Shigella/enteroinvasive E. coli and 7 Shiga toxin-producing E. coli (STEC). Among the 735 DEC isolates, 299 (40.7%) were isolated from children less than 5 years old. High resistance rates were observed to streptomycin (90.7%), ampicillin (63.4%), nalidixic acid (61.1%), sulfisoxazole (49.1%), tetracycline (41.2%), trimethoprim (35.6%), trimethoprim-sulfamethoxazole (35.4%), followed by amoxicillin-clavulanic acid (27.2%), cefotaxime (24.5%), cefepime (23.5%), gentamicin (16.7%), ceftazidime (12.4%), chloramphenicol (10.6%), ciprofloxacin (7.2%) and ofloxacin (3.4%). All the isolates were susceptible to imipenem. In addition, potential virulence genes were screened by polymerase chain reaction. A total of 15 enterotoxigenic E. coli belonging to the same clone were identified to be associated with nosocomial neonatal diarrhea and resistant to greater than 10 antimicrobials., Conclusion: Our findings suggest that active surveillance programs combining both phenotypic and genetic data would help identify disease outbreaks and strengthen antibiotic management.

Background: Fascicular ventricular tachycardia (FVT) is a common form of sustained idiopathic left ventricular tachycardia with an Asian preponderance. This study aimed to prospectively investigate long-term clinical outcomes of patients undergoing ablation of FVT and identify predictors of arrhythmia recurrence., Methods and Results: Consecutive patients undergoing FVT ablation at a single tertiary center were enrolled. Activation mapping was performed to identify the earliest presystolic Purkinje potential during FVT that was targeted by radiofrequency ablation. Follow-up with clinic visits, ECG, and Holter monitoring was performed at least every 6 months. A total of 120 consecutive patients (mean age, 29.3±12.7 years; 82% men; all patients with normal ejection fraction) were enrolled. FVT involved left posterior fascicle and left anterior fascicle in 118 and 2 subjects, respectively. VT was noninducible in 3 patients, and ablation was acutely successful in 117 patients. With a median follow-up of 55.7 months, VT of a similar ECG morphology recurred in 17 patients, and repeat procedure confirmed FVT recurrence involving the same fascicle. Shorter VT cycle length was the only significant predictor of FVT recurrence (P=0.03). Six other patients developed new-onset upper septal FVT that was successfully ablated., Conclusions: Ablation of FVT guided by activation mapping is associated with a single procedural success rate without the use of antiarrhythmic drugs of 80.3%. Arrhythmia recurrences after an initially successful ablation were caused by recurrent FVT involving the same fascicle in two thirds of patients or new onset of upper septal FVT in the remainder., (© 2015 The Authors.)

Water use efficiency (WUE) measures the trade-off between carbon gain and water loss of terrestrial ecosystems, and better understanding its dynamics and controlling factors is essential for predicting ecosystem responses to climate change. We assessed the magnitude, spatial patterns, and trends of WUE of China's terrestrial ecosystems and its responses to drought using a process-based ecosystem model. During the period from 2000 to 2011, the national average annual WUE (net primary productivity (NPP)/evapotranspiration (ET)) of China was 0.79 g C kg(-1) H2O. Annual WUE decreased in the southern regions because of the decrease in NPP and the increase in ET and increased in most northern regions mainly because of the increase in NPP. Droughts usually increased annual WUE in Northeast China and central Inner Mongolia but decreased annual WUE in central China. "Turning-points" were observed for southern China where moderate and extreme droughts reduced annual WUE and severe drought slightly increased annual WUE. The cumulative lagged effect of drought on monthly WUE varied by region. Our findings have implications for ecosystem management and climate policy making. WUE is expected to continue to change under future climate change particularly as drought is projected to increase in both frequency and severity.

Context: Nicotinamide N-methyltransferase (NNMT) is a novel histone methylation modulator that regulates energy metabolism, and NNMT knockdown prevents diet-induced obesity in mice. However, whether NNMT plays a role in human obesity and type 2 diabetes (T2DM) remains to be elucidated., Objective: NNMT catalyzes methylation of nicotinamide to generate N(1)-methylnicotinamide (me-NAM). We aimed to investigate the associations of serum me-NAM with obesity and T2DM in Chinese., Design, Setting, and Participants: The study subjects (n = 1160) were recruited from Dali, a city of Yunnan Province, in southwest China. Anthropometric phenotypes, fasting glucose, and serum lipids were measured. Serum me-NAM was measured by liquid chromatography-mass spectrometry., Results: Serum me-NAM was positively correlated with body mass index and waist circumference and negatively with high-density lipoprotein (P ≤ .03). The correlations remained highly significant in the multivariate adjusted correlation analyses. In men (n = 691), positive correlations between me-NAM and fasting glucose, low-density lipoprotein, liver function, and serum creatinine levels were also observed in both simple and multivariate adjusted correlation analyses. In multiple logistic regression analyses, elevated serum me-NAM was associated with higher risks for overweight/obesity (odds ratios, 2.36 and 5.78; 95% confidence intervals, 1.10-5.08 and 1.78-18.76 for men and women, respectively; P ≤ .03) and diabetes (odds ratios, 1.56 and 1.86; 95% confidence intervals, 1.10-2.22 and 1.05-3.31 for men and women, respectively; P ≤ .03)., Conclusions: This first large-scale population study shows that me-NAM, as an indicator of NNMT activity, is strongly associated with obesity and diabetes, supporting NNMT as a potential target for treating obesity and diabetes in humans.

Background: Hepatitis C virus (HCV) genotype and subtype are related to disease progression and response to antiviral therapy. Current HCV genotype and subtype distribution data, especially for genotypes 3 and 6, are limited in China. Our purpose was to investigate the current HCV genotype and subtype distributions in chronic hepatitis C patients in China., Methods: Chronic hepatitis C patients (n = 1012) were enrolled, and demographic information and possible transmission risk factors were collected. Serum samples were subjected to reverse-transcription polymerase chain reaction, followed by direct DNA sequencing and phylogenetic analysis of the NS5B and core/E1 regions to determine HCV genotypes/subtypes. The geographical distributions of HCV genotypes/subtypes were analyzed. Demographic information and transmission risk factors were compared between different HCV genotypes/subtypes., Results: Four genotypes and seven subtypes of HCV were detected in 970 patients. Subtypes 1b, 2a, 3a, 6a, 3b, 6n, and 1a were detected at frequencies of 71.96%, 19.90%, 3.20%, 2.16%, 1.96%, 0.41%, and 0.41%, respectively. Genotypes 3 and 6 showed an increasingly wide geographic distribution over time. Patients with subtypes 1b and 2a were older than those with 3a, 3b, 6a, and 6n subtypes (p < 0.05 in all subtypes). More genotype 1 and 2 patients underwent blood transfusion than those with genotype 3 (all p < 0.05). More genotype 3 and 6 patients had a history of intravenous drug use than those with genotypes 1 and 2 (all p < 0.05)., Conclusions: Though subtypes 1b and 2a are still the most prevalent HCV subtypes in China, genotype 3 and 6 HCV infections have already spread nationwide from southern and western China.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a cardiomyopathy that primarily involves the right ventricle. Mutations in desmosomal genes have been associated with ARVC. But its prevalence and spectrum are much less defined in the Chinese population, especially Han Chinese, a majority ethnic group in China; also the genotype-phenotype correlation regarding left ventricular involvement is still poorly understood. The aim of this study was to elucidate the genotype in Han Chinese patients with ARVC and the phenotype regarding cardiac left ventricle involvement in mutation carriers of ARVC. 48 Han Chinese patients were recruited into the present study based on the Original International Task Force Criteria of ARVC. Clinical data were reassessed according to the modified criteria published in 2010. A total of 36 subjects were diagnosed with ARVC; 12 patients were diagnosed with suspected ARVC. Five desmosomal genes (PKP2, DSG2, DSP, DSC2 and JUP) were sequenced directly from genomic DNA. Among the 36 patients, 21 mutations, 12 of which novel, were discovered in 19 individuals (19 of 36, 53%). The distribution of the mutations was 25% in PKP2, 14% in DSP, 11% in DSG2, 6% in JUP, and 3% in DSC2. Multiple mutations were identified in 2 subjects (2 of 36, 6%); both had digenic heterozygosity. Eight mutations, of which six were novel, were located in highly conserved regions. Seven mutations introduced a stop codon prematurely, which would result in premature termination of the protein synthesis. Two-dimensional echocardiography showed that LDVd and LDVs parameters were significantly larger in nonsense mutation carriers than in carriers of other mutations. In this comprehensive desmosome genetic analysis, 21 mutations were identified in five desmosomal genes in a group of 48 local Han Chinese subjects with ARVC, 12 of which were novel. PKP2 mutations were the most common variants. Left ventricular involvement could be a sign that the patient is a carrier of a nonsense cardiac desmosomal gene mutation., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

A total of 123 enterotoxigenic Escherichia coli (ETEC) isolates from diarrheal patients from June to December 2012 in Shanghai, China, were examined to determine their genetic relatedness using multilocus sequence typing and pulsed-field gel electrophoresis (PFGE) and for the presence of virulence genes and antimicrobial susceptibility. Twenty-nine sequence types (STs) and 63 PFGE patterns were identified, and results from the 2 subtyping methods correlated well. The 12 isolates of PFGE cluster B all belonged to ST-2332 and were associated with nosocomial neonatal diarrhea. Isolates of a cluster usually had the same set of virulence factors, whereas isolates of different PFGE clusters carried diverse combinations of virulence determinants. Isolates belonging to ST-2332 and ST-182 (n=9) were resistant to at least 6 antimicrobials. Our findings highlighted the need of active surveillance programs for infectious diseases collecting data at both epidemiological and genetic levels that can detect high-risk lineages of pathogens in order to rapidly identify disease outbreaks., (Copyright © 2015 Elsevier Inc. All rights reserved.)

A new moisture adjusted vegetation index (MAVI) is proposed using the red, near infrared, and shortwave infrared (SWIR) reflectance in band-ratio form in this paper. The effectiveness of MAVI in retrieving leaf area index (LAI) is investigated using Landsat-5 data and field LAI measurements in two forest and two grassland areas. The ability of MAVI to retrieve forest LAI under different background conditions is further evaluated using canopy reflectance of Jack Pine and Black Spruce forests simulated by the 4-Scale model. Compared with several commonly used two-band vegetation index, such as normalized difference vegetation index, soil adjusted vegetation index, modified soil adjusted vegetation index, optimized soil adjusted vegetation index, MAVI is a better predictor of LAI, on average, which can explain 70% of variations of LAI in the four study areas. Similar to other SWIR-related three-band vegetation index, such as modified normalized difference vegetation index (MNDVI) and reduced simple ratio (RSR), MAVI is able to reduce the background reflectance effects on forest canopy LAI retrieval. MAVI is more suitable for retrieving LAI than RSR and MNDVI, because it avoids the difficulty in properly determining the maximum and minimum SWIR values required in RSR and MNDVI, which improves the robustness of MAVI in retrieving LAI of different land cover types. Moreover, MAVI is expressed as ratios between different spectral bands, greatly reducing the noise caused by topographical variations, which makes it more suitable for applications in mountainous area.

Affected by natural and anthropogenic disturbances such as forest fires, insect-induced mortality and harvesting, forest stand age plays an important role in determining the distribution of carbon pools and fluxes in a variety of forest ecosystems. An improved understanding of the relationship between net primary productivity (NPP) and stand age (i.e., age-related increase and decline in forest productivity) is essential for the simulation and prediction of the global carbon cycle at annual, decadal, centurial, or even longer temporal scales. In this paper, we developed functions describing the relationship between national mean NPP and stand age using stand age information derived from forest inventory data and NPP simulated by the BEPS (Boreal Ecosystem Productivity Simulator) model in 2001. Due to differences in ecobiophysical characteristics of different forest types, NPP-age equations were developed for five typical forest ecosystems in China (deciduous needleleaf forest (DNF), evergreen needleleaf forest in tropic and subtropical zones (ENF-S), deciduous broadleaf forest (DBF), evergreen broadleaf forest (EBF), and mixed broadleaf forest (MBF)). For DNF, ENF-S, EBF, and MBF, changes in NPP with age were well fitted with a common non-linear function, with R(2) values equal to 0.90, 0.75, 0.66, and 0.67, respectively. In contrast, a second order polynomial was best suitable for simulating the change of NPP for DBF, with an R(2) value of 0.79. The timing and magnitude of the maximum NPP varied with forest types. DNF, EBF, and MBF reached the peak NPP at the age of 54, 40, and 32 years, respectively, while the NPP of ENF-S maximizes at the age of 13 years. The highest NPP of DBF appeared at 122 years. NPP was generally lower in older stands with the exception of DBF, and this particular finding runs counter to the paradigm of age-related decline in forest growth. Evaluation based on measurements of NPP and stand age at the plot-level demonstrates the reliability and applicability of the fitted NPP-age relationships. These relationships were used to replace the normalized NPP-age relationship used in the original InTEC (Integrated Terrestrial Ecosystem Carbon) model, to improve the accuracy of estimated carbon balance for China's forest ecosystems. With the revised NPP-age relationship, the InTEC model simulated a larger carbon source from 1950-1980 and a larger carbon sink from 1985-2001 for China's forests than the original InTEC model did because of the modification to the age-related carbon dynamics in forests. This finding confirms the importance of considering the dynamics of NPP related to forest age in estimating regional and global terrestrial carbon budgets., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Background: Atrial tachycardia (AT) is commonly encountered after atrial fibrillation (AF) ablation. But no study exclusively on noncavotricuspid isthmus-dependent right AT (NCTI-RAT) post-AF ablation has been reported. The present study aims to describe its prevalence, electrophysiological mechanisms, and ablation strategy and to further discuss its relationship with AF., Methods: From July 2006 to November 2009, 350 consecutive patients underwent catheter ablation for paroxysmal AF. A total of seven patients (2.0%) developed NCTI-RAT after left atrium ablation for AF. In these highly selected patients (two male, mean age 54 ± 11 years, mean left atrium diameter of 34 ± 7 cm), all had circumferential pulmonary vein isolation in their initial procedures and three of them had additional complex fractionated electrograms ablation in the left atrium and the coronary sinus., Results: Totally, nine NCTI-RATs were mapped and successfully ablated in the right atrium with a mean cycle length of 273 ± 64 ms in seven patients. Five ATs in three patients were electrophysiologically proved to be macroreentry and the remaining four were focal activation. All the ATs were successfully abolished by catheter ablation. After a mean follow-up of 29 ± 15 months post-AT ablation, all patients were free of AT and AF off antiarrhythmic drugs., Conclusions:  NCTI-RAT is relatively less common post-AF ablation. Totally, 2.0% of paroxysmal AF patients were revealed to have NCTI-RAT., (©2010, The Authors. Journal compilation ©2010 Wiley Periodicals, Inc.)

Objective: To compare the pharmacokinetic (PK) profiles and bioequivalence of the extended-release (ER) and immediate-release (IR) formulations of dexibuprofen (DI) in healthy Chinese volunteers after single dose and multiple doses., Materials: Zefen® (IR capsule, containing 150 mg DI, Suzhou No.4 Pharmaceutical Factory, Jiangsu, China) and ER capsule (containing 225 mg DI, Tianjin Zhongtian Pharmaceutical Co. Ltd., Tianjin, China)., Methods: This was an open, randomized, two-period crossover study. Eligible subjects were healthy male Chinese volunteers. 22 subjects were randomly assigned to receive a single 450 mg dose of the test or reference formulation on the first day. During the next 6 days, the test group received a multiple-dose of ER DI capsule (450 mg, b.i.d.) and the reference group took a multiple-dose of IR DI capsule (300 mg, t.i.d.), respectively. Multiple blood samples were collected, and plasma concentrations of DI were analyzed using high performance liquid chromatography (HPLC) system. After a 9-day washout period, the subjects were administered the alternate formulation. Bioequivalence was concluded if the 90% confidence interval (CI) for the ratio between test and reference was within accepted limits. Adverse events (AEs) were monitored and documented throughout the confinement in the clinic and washout phases of each study period., Results: 21 subjects completed the single dose administration and 20 subjects were evaluable for the multiple doses PK parameters. Single-dose Mean AUC0-t and AUC0-inf for ER formulation were 116.14 ± 21.54 mg·h/l and 117.60 ± 22.27 mg·h/l, and for IR formulation, were 107.25 ± 23.48 mg·h/l and 108.18 ± 23.93 mg·h/l, with the 90% CI within the limits accepted for bioequivalence. Mean Cmax for ER and IR formulations were 22.30 ± 5.17 mg/l and 30.26 ± 13.54 mg/l, respectively. And median tmax for ER and IR formulations were 4.5 h and 2.0 h. The retard quotient (delta R) for ER product was 1.9 ± 0.93, which indicated an intermediate extended release effect. Multiple-dose Mean AUC0-24 for ER formulation was 217.93 ± 41.07 mg·h/l and for IR formulation was 199.33 ± 37.32 mg·h/l. Other PK parameters of ER and IR formulations were as follows: median tmax were 4.8 h and 2.0 h, Css-max were 20.21 ± 2.69 mg/l and 19.71 ± 3.46 mg/l, Css-min were 2.47 ± 0.99 mg/l and 2.48 ± 0.99 mg/l, Cav were 9.08 ± 1.71 mg/l and 8.31 ± 1.56 mg/l, respectively., Conclusions: This study found that in these subjects, the absorption rates of the two DI formulations were not bioequivalent, but at steady state, the daily exposure provided by less frequent DI ER dosing was not significantly different from the same daily dose with DI IR capsules, administered more frequently.

Background: The incidence and clinical implication of dissociated pulmonary vein (PV) electrical activities after circumferential antrum PV ablation for paroxysmal atrial fibrillation (AF) remains unclear., Methods and Results: A total of 196 patients with symptomatic paroxysmal AF who underwent circumferential antrum PV ablation were prospectively studied. Dissociated PV electrical activities were observed in 101 patients (Group 1), but absent in the remaining 95 patients (Group 2). There were no significant differences in the baseline clinical characteristics between them, except that Group 2 had a higher prevalence of hypertension (30 vs. 44%, P = 0.04). After 21.8 ± 7.9 months of follow-up, 148 had no recurrence of AF after the initial procedure. AF recurrence rate was significantly higher in Group 2 than in Group 1 (P = 0.023). Relapse of PV conduction was the major cause of AF recurrence in both groups (16/16 vs. 19/23, P = 0.08), and the overall procedural success rate after the redo ablation procedure was similar in the 2 groups (90 vs. 86%, P = 0.44). However, the total number of patients with non-PV foci was significantly higher in Group 2 than in Group 1 (12/95 vs. 2/101, P < 0.01)., Conclusions: Dissociated PV electrical activities might identify a subgroup of patients with relatively higher initial procedural success with circumferential PV antrum ablation.

Purpose: This study evaluated the performance of the model for end-stage liver disease (MELD) in predicting post-transplant survival in a cohort of Chinese patients, and compared its predictive ability with that of the Child-Pugh score., Methods: The study enrolled 117 adult Chinese patients undergoing liver transplantation for benign end-stage liver diseases from January 1998 to January 2007 to evaluate the baseline characteristics and outcomes., Results: In a median follow-up duration of 90 weeks (range 0.2-373 weeks), 30 patients died. The 3-month and 1-year mortality rates of recipients in group 1 (MELD score <28) were 1.1% and 5.6%, in group 2 (MELD score 28-38) 18.8% and 50.0%, and in group 3 (MELD score >38) 91.7% and 91.7%, respectively. A statistical difference was observed in the mortality rates between the three groups (P < 0.001). At 3 months, the area under the receiver operating characteristic curve of the MELD (0.950) was significantly higher than that of the Child-Pugh score (0.810; P < 0.05)., Conclusions: Both the MELD and Child-Pugh score are valid models to predict the short-term or medium-term outcome of Chinese recipients undergoing liver transplantation for benign end-stage liver diseases. The MELD is superior to the Child-Pugh score in predicting the 3-month mortality post-transplantation.

We analyzed the shape and distribution of epsilon waves by 3 various methods of electrocardiographic recording in patients with arrhythmogenic right ventricular cardiomyopathy.Thirty-two patients who met recognized diagnostic criteria for arrhythmogenic right ventricular cardiomyopathy were included in this study (24 men and 8 women; mean age, 42.3 ± 12.9 yr). Epsilon waves were detected by standard 12-lead electrocardiography (S-ECG), right-sided precordial lead electrocardiography (R-ECG), and Fontaine bipolar precordial lead electrocardiography (F-ECG). We found 3 types of epsilon waves: wiggle waves, small spike waves, and smooth potential waves that formed an atypical prolonged R' wave. The most common configuration was small spiked waves. In some circumstances, epsilon waves were evident in some leads (especially in leads V(1) through V(3)), but notches were recorded in the other leads during the corresponding phase. These waves could be detected only by S-ECG in 1 patient, R-ECG in 3 patients, and F-ECG in 5 patients; the rates of epsilon-wave detection by these 3 methods were 38% (12/32), 38% (12/32), and 50% (16/32), respectively. However, the detection rate using combined methods was significantly higher than that by S-ECG alone (SF-ECG 56% vs S-ECG 38%, P = 0.0312; and SRF-ECG 66% vs S-ECG 38%, P = 0.0039). In addition, the rate of widespread T-wave inversion (exceeding V(3)) was significantly higher in patients with epsilon waves than in those without (48% vs 9%, P = 0.029), as was ventricular tachycardia (95% vs 64%, P = 0.019).These 3 electrocardiographic recording methods should be used in combination to improve the detection rate of epsilon waves.

Aboveground biomass (AGB) of forests is an important component of the global carbon cycle. In this study, Landsat ETM(+) images and field forest inventory data were used to estimate AGB of forests in Liping County, Guizhou Province, China. Three different vegetation indices, including simple ratio (SR), reduced simple ratio (RSR), and normalized difference vegetation index (NDVI), were calculated from atmospherically corrected ETM(+) reflectance images. A leaf area index (LAI) map was produced from the RSR map using a regression model based on measured LAI and RSR. The LAI map was then used to develop an initial AGB map, from which forest stand age was deduced. Vegetation indices, LAI, and forest stand age were together used to develop AGB estimation models for different forest types through a stepwise regression analysis. Significant predictors of AGB changed with forest types. LAI and NDVI were significant predictors of AGB for Chinese fir (R(2)=0.93). The model using LAI and stand age as predictors explained 94% of the AGB variance for coniferous forests. Stand age captured 79% of the AGB variance for broadleaved forests (R(2)=0.792). AGB of mixed forests was predicted well by LAI and SR (R(2)=0.931). Without differentiating among forest types, the model with SR and LAI as predictors was able to explain 90% of AGB variances of all forests. In Liping County, AGB shows a strong gradient that increases from northeast to southwest. About 64% of the forests have AGB in the range from 90 to 180 t ha(-1).

Local topography significantly affects spatial variations of climatic variables and soil water movement in complex terrain. Therefore, the distribution and productivity of ecosystems are closely linked to topography. Using a coupled terrestrial carbon and hydrological model (BEPS-TerrainLab model), the topographic effects on the net primary productivity (NPP) are analyzed through four modelling experiments for a 5700 km(2) area in Baohe River basin, Shaanxi Province, northwest of China. The model was able to capture 81% of the variability in NPP estimated from tree rings, with a mean relative error of 3.1%. The average NPP in 2003 for the study area was 741 gCm(-2)yr(-1) from a model run including topographic effects on the distributions of climate variables and lateral flow of ground water. Topography has considerable effect on NPP, which peaks near 1350 m above the sea level. An elevation increase of 100 m above this level reduces the average annual NPP by about 25 gCm(-2). The terrain aspect gives rise to a NPP change of 5% for forests located below 1900 m as a result of its influence on incident solar radiation. For the whole study area, a simulation totally excluding topographic effects on the distributions of climatic variables and ground water movement overestimated the average NPP by 5%.

This research attempts to model the complexity of planting trees to increase China's CO(2) sequestration potential by using a GIS-based integrated assessment (IA) approach. We use the IA model to assess the impact of China's Grain for Green reforestation and afforestation program on farmer and state incomes as well as CO(2) sequestration in Liping County, Guizhou Province. The IA model consists of five sub-models for carbon sequestration, crop income, timber income, Grain for Green, and carbon credits. It also includes a complementary qualitative module for assessing program impacts by gender and ethnicity. Using four scenarios with various assumptions about types of trees planted, crop incomes by township, CO(2) credit prices, state subsidies, methods for estimating carbon sequestered, and harvesting of trees, we find great variation in the impact of the Grain for Green program on incomes and on carbon sequestered over a 48 year period at both the county and township levels.