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Abstract Understanding the spatiotemporal variation and drivers of ecosystem services is fundamental to optimal management and sustainable development of World Heritage (WH) sites. Although WH sites face multiple natural and anthropogenic threats, our understanding of their ecosystem services is still limited, especially for karst WH sites. In this study, we assessed habitat quality (HQ), carbon storage (CS), soil retention (SR), water conservation (WC), and the combined ecosystem service (CES) of karst and non-karst WH sites in Southwest China from 2000 to 2020 using the InVEST model. We also assessed trade-offs/synergies among ecosystem services using the spatial overlay method, and identified driving factors of variation in ecosystem services using geographical detector and structural equation models. The results showed that ecosystem services of the WH sites exhibited high spatiotemporal variation. In particular, there were higher values in the property zone than in the buffer zone, and an increasing trend in SR but a decreasing trend in HQ and CES over time. Compared to non-karst sites, karst WH sites had significantly lower values of HQ, CS, SR, and CES, but higher spatial heterogeneity in CS, WC, and CES. Weak trade-offs among ecosystem services dominated the WH sites, with the proportion of weak synergies increasing over time. Compared to non-karst sites, karst WH sites had a significantly lower proportion of strong synergies and a significantly higher proportion of weak synergies. The provision of ecosystem services was primarily influenced by natural factors (e.g., landscape division index and normalized difference vegetation index), followed by anthropogenic factors (e.g., distance from road and population density). Overall, these findings may have important implications for decision-making aimed at protecting the outstanding universal value, authenticity, and integrity of WH with different attributes.

Background: The diameter and shape of the left atrial appendage (LAA) orifices may influence occluder selection and the outcomes of left atrial appendage closure (LAAC) procedure. This study aimed to evaluate the impact of LAA orifice diameter on the safety and efficacy of LAAC using the LAmbre device. Methods: A total of 133 patients with nonvalvular atrial fibrillation (AF) who underwent LAAC with the LAmbre device between June 2018 and June 2020 were included in this study. The patients were categorized into two groups based on the maximal diameter of the LAA orifice: the large LAA group (n = 45) with a maximal orifice diameter of ≥31 mm, and the normal LAA group (n = 88) with a maximal orifice diameter of

The World Natural Heritage Sites (WNHSs), which have unique ecosystems, ecological landscapes, and biodiversity, are the common heritage of all of humanity. The evolutionary pathway of ecosystem services (ESs) in the Karst WNHS between the years 2000 and 2020 has been examined, and the trade-offs and synergies among the ESs have been quantified. This research serves as a point of reference for the rational utilization of natural resources and for the protection of the ecological environment within the Karst WNHS. This research aims to assess the following ESs in the Karst WNHS, for the period 2000–2020: water conservation (WC), soil conservation (SC), carbon sequestration (CS), and habitat quality (HQ). Additionally, the objective of this study is to examine the space–time evolution of these ESs. Spearman’s correlation coefficient and spatial auto-correlation analyses were utilized to ascertain the temporal and spatial trade-offs and synergies for each ES. The results of this study indicate the following: (1) Between the years 2000 and 2020, the inter-annual changes in HQ and CS at the Shibing and Libo-Huanjiang WNHS exhibited a relatively stable pattern, with a gradual increasing trend, and in contrast, the inter-annual changes in WC and SC exhibited greater fluctuations; (2) the distribution of ESs is closely linked to land use patterns, and woodland is the most critical land type of the ESs, contributing the most to each ES; (3) population density is negatively correlated with various ecosystem services, while GDP is positively correlated with each ecosystem service; and (4) the Karst WNHS in Southern China demonstrates a clear and significant synergistic relationship between WC and CS. This relationship is primarily characterised by a strong synergistic effect. The synergistic relationship between HQ and WC exhibited a weakening trend within both study areas. Furthermore, the SC demonstrated a spatial trade-off relation with HQ, CS, and WC.

Background: Pericardial effusion or pericardial tamponade (PE/PT) is a relatively common complication of left atrial appendage closure (LAAC). However, delayed PE/PT is rare with limited data. The aim of the study was to analyze the incidence and clinical consequences of delayed PE/PT following LAAC. Methods: Patients with nonvalvular AF who were successfully implanted with LAAC devices from October 2014 to April 2021 were consecutively screened. Subjects experiencing delayed PE/PT after LAAC were included. All treatment sessions of the subjects were recorded in detail. After discharge, the patients were followed up for clinical outcomes. Results: A total of 748 patients with successful LAAC [nitinol cage device (475 Watchman 2.5), nitinol plug device (131 ACP and 142 LAmbre)] were screened. Six patients experienced delayed PE/PT (1 Watchman, 2 ACP, 3 LAmbre). The incidence of delayed PE/PT was higher in patients with a nitinol plug device (1.8% vs. 0.2%, P = 0.027). Bloody PE only occurred in patients with a nitinol plug device (5/273, 1.8%). All the patients accepted pericardiocentesis and discontinuing antithrombotic medication, and none of the patients died or needed cardiac surgery. All patients were followed up for 810 (598, 1174) days after discharge. None of them developed constrictive pericarditis or thromboembolic or major bleeding events. Conclusion: Delayed PE/PT is rare but can occur, and the incidence of delayed bloody PE/PT for the nitinol plug device was higher than that for the nitinol cage device. The strategy of emergency pericardiocentesis combined with discontinuing antithrombotic medication may be effective for delayed bloody PE/PT.

The core ecosystem functioning (e.g. trophic transfer efficiency) is at risk of being disrupted by the growing mismatch between nutrient content of primary producers and nutrient demand of grazing consumers. Ecological stoichiometry provides a conceptual framework that explains this trophic interaction using C, N and P elemental composition across trophic levels. In light of ongoing climate change and eutrophication, previous studies have raised concerns regarding the growing stoichiometric mismatch between phytoplankton and zooplankton, given the stoichiometric plasticity of phytoplankton. However, there is currently little conclusive evidence on the stoichiometric mismatch from a dual perspective of phytoplankton and zooplankton. To address this, we conducted a mesocosm experiment to investigate the separate and combined effects of climate warming (a constant increase of +3.5 ​°C plus heat waves) and eutrophication (nutrient addition) on stoichiometric mismatch between phytoplankton and zooplankton by examining stoichiometric changes in both communities. We observed a growing trend in stoichiometric mismatches when warming or nutrient addition acted individually, which was mediated by the increase in nutrient demand (N, P elements) of zooplankton growth. However, when these stressors acted jointly, the mismatches were reversed. This could be because climate warming and eutrophication combined would lead to changes in species composition, which accordingly reshaped the stoichiometric composition at the community level. These results illustrate the need of stoichiometric mismatches for understanding the implication of global change on trophic interactions and ecosystem functioning, requiring consideration not only of cross-trophic levels but also of compositional changes within communities.

BackgroundMarshall vein ethanol infusion (MVEI) as an additional therapy to conventional catheter ablation (CA) has been proved to be efficacious in patients with persistent atrial fibrillation (PeAF). However, whether empirical MVEI could be the first-line strategy in mitral isthmus (MI) ablation has seldom been investigated. Here, we aim to compare the efficacy, safety, and long-term outcomes between provisional and empirical MVEI in PeAF patients undergoing the index MI ablation procedure.MethodsWe enrolled 133 patients with PeAF either in the provisional group (n = 38, MVEI was performed when conventional endocardial and/or epicardial ablation procedures were inadequate to achieve bidirectional MI block) or in the empirical group (n = 95, MVEI was performed empirically before MI CA).ResultsAll of the baseline characteristics were comparable. Less spontaneous or inducible atrial tachycardias (ATs) were encountered in the empirical group of patients (P

Background/Purpose: Anticoagulant therapy is suggested within 45 days after Watchman device implantation for stroke prevention in patients with atrial fibrillation (AF). A previous study demonstrated that non-vitamin K antagonist oral anticoagulants (NOACs) were a feasible peri- and postprocedural alternative to warfarin. The present study aimed to compare the safety and efficacy of using different anticoagulants (low-dose NOACs vs. warfarin) within 45 days after Watchman device implantation in a Chinese population. Methods: Patients with successful Watchman device implantation from October 2014 to June 2020 were included. All patients received anticoagulants within 45 days after the procedure, and those patients were divided into three groups according to the type of postprocedural anticoagulants. Transesophageal echocardiography follow-up was performed 45 days post procedure to assess residual flow and the occurrence of device-related thrombus (DRT). Results: A total of 368 patients were enrolled in the study. The study population was divided into three groups: the warfarin group (n = 77), the dabigatran group (n = 165) and the rivaroxaban group (n = 126). Periprocedural major bleeding was higher in the warfarin group (2.6% vs. 0% vs. 0%, P = 0.043), while minor bleeding was comparable among the groups (3.9% vs. 1.2% vs. 0.8%, P = 0.230). No periprocedural transient ischemic attack/stroke occurred. At follow-up, the incidence of DRT was higher in the warfarin group than in the other groups (4.2% vs. 0.6% vs. 0.8%; P = 0.116), but the difference was not statistically significant. The rates of thromboembolic and bleeding events were similar in the three groups. Conclusion: The safety and efficacy of low-dose dabigatran and rivaroxaban were comparable to those of warfarin within 45 days after Watchman device implantation in a Chinese population.

Abstract Atrial fibrosis occurs frequently with structural heart disease and is considered as a major cause of arrhythmia. Microarray-based profiling predicted the differential expression of SPP1 in atrial fibrosis. Herein, we aimed to analyze the role of shRNA-mediated SPP1 knockdown in the progression of atrial fibrosis as well as the downstream mechanism. In vivo model in mice and in vitro HL-1 cell model of atrial fibrosis were developed by the angiotensin II (Ang II) method, where SPP1 expression was validated by RT-qPCR. Gain- and loss-of-function experiments were performed in Ang II-induced mice and HL-1 cells to evaluate the effect of the SPP1/TGF-β/SREBP2/PCSK9 axis on cell viability, apoptosis, collagen production and mitochondrial DNA (mtDNA) damage in atrial fibrosis. Expression of SPP1, TGF-β, SREBP2 and PCSK9 was increased in Ang II-induced mice and HL-1 cells. Silencing of SPP1 inhibited the occurrence of atrial fibrosis, as reflected by attenuated cell viability and collagen production as well as increased cell apoptosis. Conversely, upregulated SPP1 enhanced atrial fibrosis, which was related to upregulation of TGF-β. In addition, TGF-β elevated the expression of SREBP2, which promoted mtDNA damage and the consequent atrial fibrosis by augmenting the expression of PCSK9. This study uncovers previously unrecognized pro-fibrotic activities of SPP1 in atrial fibrosis, which is achieved through activation of the TGF-β/SREBP2/PCSK9 signaling pathway and promotion of mtDNA damage.

Bacteria in lake water bodies and sediments play crucial roles in various biogeochemical processes. In this study, we conducted a comprehensive analysis of bacterioplankton and sedimentary bacteria community composition and assembly processes across multiple seasons in 18 outdoor mesocosms exposed to three temperature scenarios. Our findings reveal that warming and seasonal changes play a vital role in shaping microbial diversity, species interactions, and community assembly disparities in water and sediment ecosystems. We observed that the bacterioplankton networks were more fragile, potentially making them susceptible to disturbances, whereas sedimentary bacteria exhibited increased stability. Constant warming and heatwaves had contrasting effects: heatwaves increased stability in both planktonic and sedimentary bacteria communities, but planktonic bacterial networks became more fragile under constant warming. Regarding bacterial assembly, stochastic processes primarily influenced the composition of planktonic and sedimentary bacteria. Constant warming intensified the stochasticity of bacterioplankton year-round, while heatwaves caused a slight shift from stochastic to deterministic in spring and autumn. In contrast, sedimentary bacteria assembly is mainly dominated by drift and remained unaffected by warming. Our study enhances our understanding of how bacterioplankton and sedimentary bacteria communities respond to global warming across multiple seasons, shedding light on the complex dynamics of microbial ecosystems in lakes.

Submerged macrophytes are vital components in shallow aquatic ecosystems, but their abundances have declined globally. Shading by periphyton and phytoplankton/turbidity plays a major role in this decline, and the competing aquatic primary producers are subject to the complex influence of multiple stressors such as increasing temperatures, nutrient loading and herbicides. Their joint impact has rarely been tested and is difficult to predict due to potentially opposing effects on the different primary producers, their interactions and their grazers. Here, we used 48 mesocosms (2500 L) to simulate shallow lakes dominated by two typical submerged macrophytes, bottom-dwelling Vallisneria denseserrulata and canopy-forming Hydrilla verticillata, and associated food web components. We applied a combination of nutrient loading, continuous warming, heat waves and glyphosate-based herbicides to test how these stressors interactively impact the growth of submerged macrophytes, phytoplankton and periphyton as competing primary producers. Warming or heat waves alone did not affect phytoplankton and periphyton abundance, but negatively influenced the biomass of V. denseserrulata. Nutrient loading alone increased phytoplankton biomass and water turbidity and thus negatively affected submerged macrophyte biomass, particularly for V. denseserrulata, by shading. Glyphosate alone did not affect biomass of each primary producer under ambient temperatures. However, heat waves facilitated phytoplankton growth under combined nutrient loading and glyphosate treatments more than continuous warming. As a consequence, H. verticillata biomass was lowest under these conditions indicating the potential of multiple stressors for macrophyte decline. Our study demonstrated that multiple stressors interactively alter the biomass of primary producers and their interactions and can eventually lead to a loss of macrophyte communities and shift to phytoplankton dominance. These results show the risks in shallow lakes and ponds in agricultural landscapes and underline the need for multiple stressor studies as a base for their future management.

Abstract Submerged macrophytes play a key role in maintaining a clear‐water phase and promoting biodiversity in shallow aquatic ecosystems. Since their abundance has declined globally due to anthropogenic activities, it is important to include them in aquatic ecosystem restoration programs. Macrophytes establishment in early spring is crucial for the subsequent growth of other warm‐adapted macrophytes. However, factors affecting this early establishment of submerged macrophytes have not been fully explored yet. Here, we conducted an outdoor experiment from winter to early spring using the submerged macrophytes Potamogeton crispus and Vallisneria spinulosa to study the effects of shading, nutrient loading, snail herbivory (Radix swinhoei), and their interactions on the early growth and stoichiometric characteristics of macrophytes. The results show that the effects strongly depend on macrophyte species. Biomass and number of shoots of P. crispus decreased, and internode length increased during low light conditions, but were not affected by nutrient loading. P. crispus shoot biomass and number showed hump‐shaped responses to increased snail biomass under full light. In contrast, the biomass of the plant linearly decreased with snail biomass under low light. This indicates an interaction of light with snail herbivory. Since snails prefer grazing on periphyton over macrophytes, a low density of snails promoted growth of P. crispus by removing periphyton competition, while herbivory on the macrophyte increased during a high density of snails. The growth of V. spinulosa was not affected by any of the factors, probably because of growth limitation by low temperature. Our study demonstrates that the interaction of light with snail herbivory may affect establishment and growth of submerged macrophytes in early spring. Macrophyte restoration projects may thus benefit from lowering water levels to increase light availability and making smart use of cold‐adapted herbivores to reduce light competition with periphyton.

The weight–length relationship (WLR) of fish is a crucial tool in fish biology research and has received extensive attention. However, fish growth is influenced by many factors, and the WLR also changes accordingly. Our aim was to investigate how fish body shape is affected by various factors by analyzing the existing parameters of the relationship between fish body length and weight. We analyzed 198,354 fish specimens belonging to 402 species of 82 families in China and investigated the change of fish body shape in the function of their ecology. Herbivorous fish tended to be shorter and fatter than carnivorous fish, and omnivorous fish fall somewhere in between. This difference could be due to variations in feeding habits and the availability of food sources. Additionally, fish living in lentic waters tended to have a shorter and fatter body shape compared to those living in lotic waters. This could be attributed to differences in swimming behavior in these environments. Furthermore, our results showed that the b value decreased as altitude increased, and fish tended to be thinner and longer due to lower oxygen and temperature levels in high-altitude waters. Overall, our study provides valuable insights into the WLR of fish and the impact of multiple factors on fish body shape.

Background/Purpose: Left atrial appendage closure (LAAC) is conventionally guided by fluoroscopy and transesophageal echocardiography. We introduce an LAAC technique without fluoroscopy exposure using intracardiac echocardiography (ICE) and electroanatomic mapping system (EAMS) under local anesthesia. Methods: Seven non-valvular atrial fibrillation patients who underwent LAAC with the LAmbre devices under the ICE and EAMS guidance were compared to 7 patients following the conventional approach by propensity score matching. ICE probe was advanced into the left atrium (LA) to guide sizing and device implantation following the orthogonal tri-axial technique (Axis-X: from left pulmonary veins [PVs] to LAA; Axis-Y: from right PV ostium to LAA; Axis-Z: from lower LA to LAA). Results: The mean diameters of ostia and landing zone were 21.4 ± 3.9 mm and 20.4 ± 4.2 mm, respectively. LAmbre devices with a mean umbrella diameter of 23.7 ± 4.2 mm and cover disc diameter of 29.4 ± 3.6 mm were successfully implanted and acute complete LAA sealing without peri-device leak (PDL) were achieved in all cases. Neither fluoroscopy exposure nor contrast consumption was recorded. No procedure related complications were documented. The mean procedural time and PDLs at follow-ups were comparable to those in the conventional group. No stroke or thromboembolic events were documented. Conclusion: The fluoroscopy exposure could be minimized, even to zero, in the ICEguided LAAC procedures feasibly and safely using LAmbre devices. The orthogonal triaxial technique is considered efficacious and safe for the procedures.

Freshwater gastropods play key roles in shallow aquatic ecosystems, with a central position in the periphyton–gastropod–fish trophic pathway, as they feed on periphyton and are preyed on by animals of higher trophic levels. Thus, it is of great interest to explore how climate change impacts the gastropod community and the trophic cascading effects on periphyton. Here, we constructed a simplified, shallow lake food web in 24 large mesocosm tanks to simulate warming (+4.5 °C) on the population responses of two common snails (Bellamya aeruginosa and Radix swinhoei) in two different systems (without/with common carp Cyprinus carpio) over 200 days. We found that warming lowered the biomass and density of R. swinhoei by 16.8% and 41.6%, respectively, and accelerated the average time of density peak of R. swinhoei by 21.5 days in the common carp-absent system. The density of B. aeruginosa in the warming with common carp group was lowered by 79.8% more than in the warming group without common carp. The averaged biomass and density of R. swinhoei in the fish-present system significantly lowered by 64.4% and 92.5%, respectively, compared to the fish-absent system. Cascading effects were also observed, as the snail communities declined under warming, that is, the grazing pressure on periphyton was less, resulting in its higher biomass. In conclusion, in the fish-absent system, warming decreased the biomass and density of the R. swinhoei, and in both snail populations, the biomass and density were much higher than those in the fish-present system. Due to the different phenology of snail species and species-specific predation, future stronger predation in a continuous warming condition might undermine the diversity of the gastropods, thereby changing food web structures in shallow freshwater ecosystems.

Background/Purpose: Experience in procedures combining left atrial appendage (LAA) closure (LAAC) and catheter ablation (CA) was scarce in Chinese nonvalvular atrial fibrillation (AF) patients with high risks for stroke and bleeding. We aimed to investigate the efficacy and safety of the combination therapy with LAAC and AF CA in a single procedure based on the multicenter data and medium-term follow-up results. Methods: A total of 122 AF patients with a mean CHA2DS2-VASc score of 4.3 ± 1.4 and HAS-BLED score of 3.3 ± 1.0 were enrolled. The Watchman (n = 83) devices were implanted either before or after AF ablations in the same procedure, while the Amplatzer Cardiac Plug (ACP, n = 39) devices were implanted immediately after CA. AF recurrence and transesophageal echocardiography results were evaluated. Results: All devices were successfully implanted and acute complete LAA occlusions were achieved in 115 (94.3%) of patients. Neither acute nor chronic peri-device leaks greater than 5 mm were detected. Oral anticoagulation was held in all patients but two with asymptomatic device-related thrombi, which were resolved after prolonged anticoagulation. AF-free success rate without antiarrhythmic drugs was 76.2% after a mean follow-up of 11.5 ± 6.8 months. No serious complications were observed during the follow-up. Conclusion: The combination therapy with LAAC and AF ablation in a single procedure was efficacious and safe in the Chinese symptomatic AF population with high risk for stroke and bleeding. Keywords: Atrial fibrillation, Catheter ablation, Left atrial appendage closure, Oral anticoagulation

Background: This research explores the relationship between the unipolar electrogram (UP-EGM) and lesion size index (LSI) in different regions of continuous circular lesions (CCLs) and to assess the safety and efficacy of UP-EGM-guided versus LSI-guided radiofrequency catheter ablation (RFCA) in patients with paroxysmal atrial fibrillation (PAF). Methods: A total of 120 patients with drug-refractory PAF who underwent index RFCA were scheduled to be consecutively included from March 2020 to April 2021. All the patients were randomly divided 1:1 into two groups: the UP-EGM group and the LSI group. The first-pass PVI rate, acute PVI rate, and the sinus rhythm maintenance rate were compared. Results: A total of 120 patients with PAF were included in the study: the UP-EGM group (n = 60) and the LSI group (n = 60). All the LSI values in the UP-EGM group were less than those in the corresponding regions in the LSI group (all p < 0.001). There were no significant differences in the first-pass PVI rate and acute PVI rate between the two groups. After a mean follow-up period of 11.31 ± 1.70 months, the sinus rhythm maintenance rate in the UP-EGM group was comparable to that in the LSI group (90% vs. 91.7%, p = 0.752). Conclusion: UP-EGM-guided and LSI-guided RFCA are both effective and safe in patients with PAF. However, UP-EGM may be more suitable than LSI for guiding individual RFCA.

Increased decomposition rates in shallow lakes with global warming might increase the release of atmospheric greenhouse gases, thereby producing positive feedback for global warming. However, how climate warming affects litter decomposition is still unclear in lake ecosystems. Here, we tested the effects of constant and variable warming on the bacterial metabolic potential of typically submerged macrophyte (Potamogeton crispus L.) litters during decomposition in 18 mesocosms (2500 L each). The results showed that warming reduced main chemoheterotrophic metabolic potential but promoted methylotrophy metabolism, which means that further warming may alter methane-cycling microbial metabolism. The nitrate reduction function was inhibited under warming treatments, and nitrogen fixation capability significantly increased under variable warming in summer. The changes in dissolved oxygen (DO), pH, conductivity and ammonium nitrogen driven by warming are the main environmental factors affecting the bacteria’s metabolic potential. The effects of warming and environmental factors on fermentation, nitrate reduction and ammonification capabilities in stem and leaf litter were different, and the bacterial potential in the stem litter were more strongly responsive to environmental factors. These findings suggest that warming may considerably alter bacterial metabolic potential in macrophyte litter, contributing to long-term positive feedback between the C and N cycle and climate.

IntroductionMultiple algorithms based on 12-lead ECG measurements have been proposed to identify the right ventricular outflow tract (RVOT) and left ventricular outflow tract (LVOT) locations from which ventricular tachycardia (VT) and frequent premature ventricular complex (PVC) originate. However, a clinical-grade machine learning algorithm that automatically analyzes characteristics of 12-lead ECGs and predicts RVOT or LVOT origins of VT and PVC is not currently available. The effective ablation sites of RVOT and LVOT, confirmed by a successful ablation procedure, provide evidence to create RVOT and LVOT labels for the machine learning model.MethodsWe randomly sampled training, validation, and testing data sets from 420 patients who underwent successful catheter ablation (CA) to treat VT or PVC, containing 340 (81%), 38 (9%), and 42 (10%) patients, respectively. We iteratively trained a machine learning algorithm supplied with 1,600,800 features extracted via our proprietary algorithm from 12-lead ECGs of the patients in the training cohort. The area under the curve (AUC) of the receiver operating characteristic curve was calculated from the internal validation data set to choose an optimal discretization cutoff threshold.ResultsThe proposed approach attained the following performance: accuracy (ACC) of 97.62 (87.44–99.99), weighted F1-score of 98.46 (90–100), AUC of 98.99 (96.89–100), sensitivity (SE) of 96.97 (82.54–99.89), and specificity (SP) of 100 (62.97–100).ConclusionsThe proposed multistage diagnostic scheme attained clinical-grade precision of prediction for LVOT and RVOT locations of VT origin with fewer applicability restrictions than prior studies.

Extreme climatic events, such as heat wave and large temperature fluctuations, are predicted to increase in frequency and intensity during the next hundred years, which may rapidly alter the composition and function of lake bacterial communities. Here, we conducted a year-long experiment to explore the effect of warming on bacterial metabolic function of lake water and sediment. Predictions of the metabolic capabilities of these communities were performed with FAPROTAX using 16S rRNA sequencing data. The results indicated that the increase in temperature changed the structure of bacterial metabolic functional groups in water and sediment. During periods of low temperature, the carbon degradation pathway decreased, and the synthesis pathway increased, under the stimulation of warming, especially under the conditions temperature fluctuation. We also observed that nitrogen fixation ability was especially important in the warming treatments during the summer season. However, an elevated temperature significantly led to reduced nitrogen fixation abilities in winter. Compared with the water column, the most predominant functional groups of nitrogen cycle in sediment were nitrite oxidation and nitrification. Variable warming significantly promoted nitrite oxidation and nitrification function in winter, and constant warming was significantly inhibited in spring, with control in sediments. Co-occurrence network results showed that warming, especially variable warming, made microbial co-occurrence networks larger, more connected and less modular, and eventually functional groups in the water column and sediment cooperated to resist warming. We concluded that warming changed bacterial functional potentials important to the biogeochemical cycling in the experimental mesocosms in winter and spring with low temperature. The effect of different bacteria metabolism functions in water column and sediment may change the carbon and nitrogen fluxes in aquatic ecosystems. In conclusion, the coupling response between different bacterial metabolic functions in water and sediment may improve the ability to mitigate climate change.

Let G(u,v) be a λ-order homogeneous function. In this paper, by discussing optimal matching parameters of the half discrete Hilbert type multiple integral inequality with quasihomogeneous kernel K(n,||x||ρ,m) = G(nλ1,||x||λ2ρ,m), several equivalent conditions of the optimal matching parameters are obtained, and a basic theoretical problem of the half discrete Hilbert type inequality is solved. Finally, their applications to operator boundedness and operator norm are discussed. [ABSTRACT FROM AUTHOR]

Catechol-O-methyltransferase (COMT) gene variation is known to be associated with the risk of acute coronary events. The purpose of the present study was to investigate the contribution of COMT promoter methylation towards the risk of coronary heart disease (CHD). COMT methylation was evaluated in 48 CHD cases and 48 well-matched non-CHD controls using bisulfite pyrosequencing technology. The results demonstrated that CHD cases had a significantly lower level of methylation at COMT CpG3 sites compared with the controls (33.77±5.71 vs. 36.42±5.00%; P=0.018). Further analysis, according to gender, showed that CpG3 methylation was associated with CHD in males (P=0.038) but not in females (P=0.253), suggesting that there is a gender disparity in the association between COMT methylation and CHD. In conclusion, it was determined that COMT CpG3 hypomethylation is associated with an increased risk of CHD in males. [ABSTRACT FROM AUTHOR]