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Microcystis blooms have a marked effect on microbial taxonomical diversity in eutrophic lakes, but their influence on the composition of microbial functional genes is still unclear. In this study, the free-living microbial functional genes (FMFG) composition was investigated in the period before Microcystis blooms (March) and during Microcystis blooms (July) using a comprehensive functional gene array (GeoChip 5.0). The composition and richness of FMFG in the water column was significantly different between these two periods. The FMFG in March was enriched in the functional categories of nitrogen, sulfur, and phosphorus cycling, whereas the FMFG in July was enriched in carbon cycling, organic remediation, and metal homeostasis. Molecular ecological network analysis further demonstrated fewer functional gene interactions and reduced complexity in July than in March. Module hubs of the March network were mediated by functional genes associated with carbon, nitrogen, sulfur, and phosphorus, whereas those in July by a metal homeostasis functional gene. We also observed stronger deterministic processes in the FMFG assembly in July than in March. Collectively, this study demonstrated that Microcystis blooms induced significant changes in FMFG composition and metabolic potential, and abundance—information, which can support the understanding and management of biogeochemical cycling in eutrophic lake ecosystems. [ABSTRACT FROM AUTHOR]

BACKGROUND: Recurrence of atrial fibrillation (AF) is common in patients with persistent AF even after multiple ablation procedures. His-Purkinje conduction system pacing (HPCSP) combined with atrioventricular node ablation (AVNA) is effective in managing patients with AF and heart failure. This study aimed to determine whether HPCSP combined with AVNA can improve quality of life and alleviate symptoms in older patients with symptomatic persistent AF refractory to multiple ablation procedures, as well as evaluate the feasibility and safety of this therapy. METHODS: Older patients (≥ 65 years) with symptomatic persistent AF refractory to at least two ablation procedures were treated with combined HPCSP and AVNA. The success rates and complications were recorded. Pacing parameters, European Heart Rhythm Association (EHRA) scores, and Atrial Fibrillation Effect on Quality-of-Life (AFEQT) scores obtained perioperatively were compared with those recorded at the 6-month follow-up examination. RESULTS: Thirty-one patients were enrolled; of those, only thirty patients were eventually treated with AVNA because one patient developed a complete atrioventricular block following the withdrawal of the His bundle pacing lead. The success rates were 100% for HPCSP (22 cases with His bundle pacing, and 9 cases with left bundle branch pacing) and 93.3% (28/30) for AVNA, respectively. By the 6-month follow-up examination, EHRA scores improved significantly (3.00 ± 0.73 vs. 2.44 ± 0.63, P = 0.014) and AFEQT scores increased markedly (49.6 ± 20.6 vs. 70.9 ± 14.0, P = 0.001). No severe complications developed. CONCLUSIONS: When used in older patients with symptomatic persistent AF refractory to multiple ablation procedures, HPCSP combined with AVNA significantly alleviated symptoms and improved quality of life during short-term follow-up. This therapy was proved to be safe and effective in this patient population. [ABSTRACT FROM AUTHOR]

Winter rapeseed (Brassica rapa L.) is an important oilseed crop in northwest China. Freezing stress severely limits its production and geographical distribution, and frequent extreme freezing events caused by climate change are increasing the chances of winter freeze-injury. However, the underlying mechanism of B. rapa response to freezing stress remains elusive. Here, B. rapa genome (v3.0) was used as a reference for the comparative transcriptomic analysis of Longyou 6 and Tianyou 2 (strong and weak cold tolerance, respectively) under different freezing stress. Before and after freezing stress, 5,982 and 11,630 unique differentially expressed genes (DEGs) between two cultivars were identified, respectively. After freezing stress, the GO terms in Tianyou 2 were mainly involved in "macromolecule biosynthetic process", and those in Longyou 6 were involved in "response to stimulus" and "oxidoreductase activity". Morphological and physiological results indicated that Longyou 6 retained a higher basal freezing resistance than Tinayou 2, and that cold acclimation could strengthen the basal freezing resistance. Freezing stress could activate the MAPK signal cascades, and the phosphorylation level of Longyou 6 showed a higher increase in response to freezing treatment than Tianyou 2. Based on our findings, it was speculated that the cell membrane of B. rapa perceives external signals under freezing stress, which are then transmitted to the nucleus through the cold-activated MAPK cascades and Ca2+-related protein kinase pathway, thus leading to activation of downstream target genes to enhance the freezing resistance of B. rapa. [ABSTRACT FROM AUTHOR]

Freshwater ecosystems are recognized as one of the important natural methane (CH4) sources, but little is known about the emission hotspots and the effects of algal blooms on CH4 production in deep lakes. In this study, carried out from the littoral (S1), pelagic (S2-S4), and the deepest site (S5), water samples from different depths and sediment cores were collected along the transect of Lake Fuxian, a deep monomictic lake to investigate the spatial–temporal variations of CH4. Dissolved methane concentration observed at the oxic metalimnion was 37.5% and 19.5% higher than that those observed at the epilimnion and at the layer between 80 and 100 m depth, respectively. During the overturn period, the vertical distribution of CH4 in the water column was uniform, with an average concentration of 0.031 ± 0.007 μM in S2–S5. Statistical analysis indicated that the CH4 concentration in the water column was significantly higher in S1 than other sites along the transect during both sampling periods. Sediment CH4 concentration and methane production potential (MPP) were also significantly higher in S1 than in other sites. Along the sediment depth, the maximum MPP was observed at 6–8 cm in S1, but it moved up to the surface layer in S2–S5 in both sampling periods. In addition, stable carbon isotope analysis indicated that the surface sediments in the pelagic zone (S2–S5) mainly comprised autochthonous organic matters. In this zone, MPP had a significantly positive correlation with sediment total organic carbon (TOC) (R2 = 0.401, p < 0.01). In summary, we described the spatial and temporal distributions of CH4 in deep Lake Fuxian, littoral zones are CH4 emission hotspots that can contribute to the CH4 accumulation in the oxic metalimnion layer during the stratification period. In the pelagic zone, autochthonous organic matter was transported into the surface sediment after a massive algal bloom, representing another hotspot for CH4 production. [ABSTRACT FROM AUTHOR]

Highlights • The grassland fire risk was assessed in remote and data lacking areas. • The grassland fire risk knowledge and experience was transferred from one region to another. • This method could conveniently be used for risk mapping and updating. • It will reduce grassland fire risk management costs. Abstract A new direction of risk assessment research in grassland fire management is data-driven prediction, in which data are collected from particular regions. Since some regions have rich datasets that can easily generate knowledge for risk prediction, and some have no data available, this study addresses how we can leverage the knowledge learned from one grassland risk assessment to assist with a current assessment task. In this paper, we first introduce the transfer learning methodology to map and update risk maps in grassland fire management, and we propose a new grassland fire risk analysis method. In this study, two major grassland areas (Xilingol and Hulunbuir) in northern China are selected as the study areas, and five representative indicators (features) are extracted from grassland fuel, fire climate, accessibility, human and social economy. Taking Xilingol as the source domain (where sufficient labelled data are available) and Hulunbuir as the target domain (which contains insufficient data but requires risk assessment/prediction), we then establish the mapping relationship between grassland fire indicators and the degrees of grassland fire risk by using a transfer learning method. Finally, the fire risk in the Hulunbuir grassland is assessed using the transfer learning method. Experiments show that the prediction accuracy reached 87.5% by using the transfer learning method, representing a significant increase over existing methods. [ABSTRACT FROM AUTHOR]

The fragile ecosystems of plateau lakes are in face of ecological risks from emerging toxic elements. Beryllium (Be) and thallium (Tl) have been considered priority control metals in recent years owing to their persistence, toxicity, and bioaccumulation. However, the toxic factors of Be and Tl are scarce and ecological risks of them in the aquatic environment were seldom investigated. Hence, this study developed a framework for calculating the potential ecological risk index (PERI) of Be and Tl in aquatic systems and used it to assess the ecological risks of Be and Tl in Lake Fuxian, a plateau lake in China. The toxicity factors of Be and Tl were calculated to be 40 and 5, respectively. In sediments of Lake Fuxian, the concentrations of Be and Tl were between 2.18 and 4.04 mg/kg and 0.72−0.94 mg/kg, respectively. The spatial distribution indicated that Be was more abundant in the eastern and southern regions, and Tl had higher concentrations near the northern and southern banks, consistent with the distribution of anthropogenic activities. The background values were calculated as 3.38 mg/kg and 0.89 mg/kg for Be and Tl, respectively. In comparison with Be, Tl was more enriched in Lake Fuxian. The increasing Tl enrichment has been attributed to anthropogenic activities (e.g., coal burning and non-ferrous metal production), especially since the 1980s. Generally, Be and Tl contamination has decreased over the past several decades, from moderate to low, since the 1980s. The ecological risk of Tl was low, whereas Be might have caused low to moderate ecological risks. In the future, the obtained toxic factors of Be and Tl in this study can be adopted in assessing the ecological risks of them in sediments. Moreover, the framework can be employed for the ecological risk assessment of other newly emerging toxic elements in the aquatic environment. [Display omitted] • The toxic factors of Be and Tl were calculated as 40 and 5, respectively. • RGBs of toxic elements can be identified using the statistical iterative 2σ method. • Tl was more enriched than Be in sediments of Lake Fuxian. • Potential ecological risks of Be and Tl were at low levels in Lake Fuxian. [ABSTRACT FROM AUTHOR]

Wastewater irrigation can elevate metal concentrations in soils and crops and increase the metal-associated health risks via vegetable ingestion in arid and semiarid northwestern China. Here, we investigated the As, Cd, Cr, Cu, Ni, Pb, and Zn concentrations in four vegetable species from Dongdagou and Xidagou farmlands in Baiyin, Gansu, China. We evaluated the effects of irrigation type (Dongdagou: industrial wastewater; Xidagou: domestic wastewater) and cultivation mode (open field and greenhouse) on the vegetable metal concentration, metal partitioning, soil-to-plant bioconcentration factor (BCF), and the health risk index. All stream waters, soils, and vegetables were found most severely polluted by As and Cd, with higher severity in the industrial-wastewater-irrigated Dongdagou than the domestic-wastewater-irrigated Xidagou. All vegetables had higher or, at least, comparable metal mass allocated in the shoot than in the root. Greenhouse cultivation could reduce metal-ingestion-associated health risks from edible vegetable biomass by decreasing the soil to plant bioaccumulation (BCF) and the metal concentration. This effect was always significant for all vegetables within Xidagou, and for carrot within Dongdagou. This mitigation effect of greenhouse cultivation could be attributed to the metal sorption by a higher level of soil organic matter and faster growth rate over metal uptake rate in greenhouses compared to open fields. Such mitigation effect was, however, insignificant for leafy vegetables within Dongdagou, when much more severely polluted water for irrigation was applied in greenhouses compared to open fields within Dongdagou. The present study highlights greenhouse cultivation as a potential mitigating approach to providing less-polluted vegetables for residents in the severely polluted area in addition to the source pollution control. [ABSTRACT FROM AUTHOR]

In recent years, Chinese service industry is developing rapidly. Compared with developed countries, service quality should be the bottleneck for Chinese service industry. On the background of three major telecommunications service providers in China, the functions of customer perceived utilities are established. With the goal of consumer’s perceived utility maximization, the classic Nash equilibrium solution and quantum equilibrium solution are obtained. Then a numerical example is studied and the changing trend of service quality and customer perceived utility is further analyzed by the influence of the entanglement operator. Finally, it is proved that quantum game solution is better than Nash equilibrium solution. [ABSTRACT FROM AUTHOR]

This study presents a methodology for risk analysis and assessment to manage grassland fire in northern China based on the Geographical Information Systems from the viewpoints of climatology, geography, disaster science, and environmental science and so on. Using natural disaster and risk assessment theory, a multi-dimensional grassland fire risk index (MGFRI) was proposed by integrating weighted comprehensive method, analytic hierarchy process, and fuzzy gamma method into natural disaster risk index. The developed MGFRI will be an easily understandable tool to manage grassland fire by comparing the risk of regions in the northern China and relative contributions of various factors, for example, hazard, exposure, vulnerability, and management ability. A scale of one to five was derived to measure the risk degree. It shows that 4.4 % of grassland falls in the category of 'very high' risk, followed by 9.6, 19.1, 60.9, and 5.9 %, respectively, in the categories 'high', 'middle', 'low', and 'very low'. The assessment results show reliability by test. The results in this study are intended to support local, provincial, and national government agencies to: (1) make resource allocation decisions; (2) make high-level planning decisions; and (3) raise public awareness of grassland fire risk, its causes, and ways to manage it. [ABSTRACT FROM AUTHOR]

Cyanobacterial blooms have become more frequent as a result of eutrophication in lakes. The accumulation and breakdown of huge cyanobacterial biomasses often cause hypoxia in lakes. However, little is known about microbial diversity in these areas. In this study, we characterized the bacterial community composition of a Microcystis-bloom-induced hypoxic area in Lake Taihu, which is a large, shallow lake, by analysing terminal restriction fragment length polymorphisms of 16 S ribosomal RNA genes and clone libraries generated from selected samples. Bacterial samples were collected at different sites within the hypoxic zone at different times during the development of hypoxia. The results showed that the composition of both free-living and particle-attached bacterial communities in the water column varied spatially and temporally and that these variations were largely related to changes in the concentrations of dissolved oxygen and ions in the water column. Sequences affiliated with Clostridium were predominantly found at the onset of hypoxia, whereas members of the LD12 cluster were detected at the posthypoxia stage; Desulfovibrio and Comamonadaceae dominated throughout the hypoxic event. We speculate that these organisms may be associated with the decomposition of Microcystis biomass and the production of volatile organic compounds; however, their specific function in Microcystis-bloom-induced hypoxia warrants further study. [ABSTRACT FROM AUTHOR]

Abstract: With rapid industrialization in China, both resource scarcity and resources efficiency have challenged the country''s sustainable development. Under such circumstance, circular economy should be adopted as a national development strategy. However, due to a lack of understanding current barriers on implementing circular economy, it is necessary to conduct a questionnaire based survey. The data and information used in this paper were collected by distributing questionnaires in 6 cities and interviewing 252 respondents. Our research findings indicated that while most of officials working at municipal and county levels have higher awareness and understanding on circular economy concept and its significance, nearly 16.70% of the interviewed officials had just heard of circular economy indicating that there is still a need for government officials to further improve their circular economy awareness. Government officials can receive their circular economy knowledge through awareness raising activities thus obtaining higher circular economy awareness. The main barriers on circular economy development are weakness of public awareness and lack of financial support, the prior method on pushing circular economy development is to execute compulsory regulations, which is shared by about 61.11% of all respondents; the gap between policy-making and practical action is still a serious problem. Nearly half of the respondents are not willing to pay more money for green products. [Copyright &y& Elsevier]

Abstract: The horizontal distribution of bloom-forming Microcystis in a specific lake area and the transport of Microcystis by wind-driven lake currents between Meiliang Bay and the open water of Taihu Lake were measured during continuous field observations from August 21 to 25, 2006. During the observations, the horizontal distributions of Microcystis, represented by Chlorophyll a, showed a clear concentration toward downwind lake areas. According to the lake currents and the Chl a concentrations on the boundary line between the Meiliang Bay and the open water, the transported Chl a was less than 2% of the total weight of Chl a in Meiliang Bay on August 22, 24 and 25. The results suggest that the horizontal distribution of the bloom-forming Microcystis was strongly affected by the wind conditions, and the wind-driven Microcystis accumulation was mainly determined by surface drift; the transport of Microcystis by lake currents was much less important in this large, shallow lake. [Copyright &y& Elsevier]

Currently, studies on the ecological risk assessment mainly focus on problems of single eco-environments or some specific ecological problem, whereas less attention has been focused on regional ecological disasters under comprehensive analysis of natural, economic, and social factors. This study presents a methodology for risk assessment and regionalization of ecological disasters in Jilin Province, China, supported by a geographic information system (GIS) and technology of natural disaster risk assessment from the viewpoints of climatology, geography, disaster science, and environmental science. The risk assessment model for ecological disasters of Jilin Province is structured by using the Natural Disaster Risk Index method, Weighted Comprehensive Analysis, and Analytic Hierarchy Process. The contribution rate of every factor to the ecological disaster risk is assessed, and the regionalization maps of each of four factors (hazard, exposure, vulnerability, and emergency response and recovery capability) forming ecological disasters risk and the ecological disasters risk in Jilin Province are drawn based on GIS. The results from this study provide scientific reference in decision-making for ecological disaster prevention and are potentially useful for rebuilding and resuming of the eco-environment. [ABSTRACT FROM AUTHOR]

The maximum quantum yield of photosystem II was estimated from variable chlorophyll a fluorescence in samples of phytoplankton collected from the Taihu Lake in China to determine the responses of different phytoplankters to irradiance and vertical mixing. Meteorological and environmental variables were also monitored synchronously. The maximum quantum yield of three phytoplankton groups: cyanobacteria, chlorophytes, and diatoms/dinoflagellates, showed a similar diurnal change pattern. F v/ F m decreased with a significant depth-dependent variation as irradiance increased during the morning and increased as irradiance declined in the afternoon. Furthermore, the rates of F v/ F m depression were dependent upon the photon flux density, whereas the rates of recovery of F v/ F m were dependent upon the historical photon density. Moreover, photoinhibition affected the instantaneous growth rates of phytoplankton. Although at noon cyanobacteria had a higher photoinhibition value (up to 41%) than chlorophytes (32%) and diatoms/dinoflagellates (34%) at the surface, no significant difference in diurnal growth rates among the three phytoplankton groups were observed indicating that cyanobacteria could photoacclimate better than chlorophytes and diatoms/dinoflagellates. In addition, cyanobacteria had a higher nonphotochemical quenching value than chlorophytes and diatoms/dinoflagellates at the surface at noon, which indicated that cyanobacteria were better at dissipating excess energy. The ratios of enclosed bottle samples F v/ F m to free lake samples F v/ F m showed different responses for the three phytoplankton groups to irradiance and vertical mixing when wind speed was approximately constant at about 3.0 m s−1. When wind speed was lower than 3.0 m s−1, cyanobacteria accumulated mainly at the surface and 0.3 m, because of their positive buoyancy, where diurnal growth rates of phytoplankton were relatively higher than those at 0.6 m and 0.9 m. Chlorophytes were homogenized completely by vertical mixing, while diatoms/dinoflagellates avoided active high irradiance by moving downward at noon, and then upward again when irradiance decreased. These results explain the dominance of cyanobacteria in Taihu Lake. [ABSTRACT FROM AUTHOR]

Background and Objective: Little is known about the outcome of catheter ablation of atrial fibrillation (AF) in patients with diabetes mellitus (DM). We investigated the safety and efficacy of catheter ablation of AF in patients with DM.Materials and Methods: Thirty one patients with DM from a group of 263 consecutive patients undergoing a first-time catheter ablation of AF procedure were enrolled in a prospective study. The ablation protocol (guided by CARTO system) consisted in two continuous circular lesions around ipsilateral pulmonary veins.Results: The following clinical characteristics differed between DM and no-DM patients: age (62.0 +/- 10.8 vs. 56.1 +/- 10.6 years, P = 0.004), longer AF history (9.6 +/- 9.3 vs. 6.7 +/- 6.3 years, P = 0.024), significantly larger left atrium size (41.1 +/- 7.8 vs. 38.3 +/- 5.8 mm, P = 0.021), hypertension (58.1 vs. 35.8%, P = 0.018) and structural heart disease (67.7 vs. 43.5%, P = 0.011). Despite a similar AF recurrence rate in DM and no-DM patients (32.3 vs. 22.4%, P = 0.240), the ablation procedure was complicated in 28 patients (11 hematomas, three cardiac tamponades and three strokes) and the incidence of complications was significantly higher in DM than in no-DM patients (29.0 vs. 8.2%, respectively, P = 0.002). Multivariate analysis showed that DM was an independent risk factor for complications occurrence (odd ratio 5.936, 95% confidence interval 2.059 to 17.112, P = 0.001).Conclusions: First catheter ablation of AF procedure in DM patients was equally efficacious than in no-DM patients. However, DM patients had a higher incidence of complications, mostly thrombotic or hemorrhagic. [ABSTRACT FROM AUTHOR]

Objective To study the relationship of remote sensing normalized differential vegetation index (NDVI) to Anopheles density and malaria incidence rate. Methods Data of monthly average climate, environment, Anopheles density and malaria incidence rate, and remote sensing NDVI were collected from 27 townships of 10 counties in southeastern Yunnan Province from 1984 to 1993. The relationship of remote sensing ecological proxy index, NDVI, to Anopheles density and malaria incidence rate was studied by principal component analysis, factor analysis and grey correlation analysis. Results The correlation matrix showed that NDVI highly correlated with Anopheles density in 4 townships of Mengla, Jinghong, and Yuanjiang counties, but in other 23 townships the relationship was not clear. Principal component and factor analyses showed that remote sensing NDVI was the representative index of the first principal component and the first common factor of Anopheles density evaluation. Grey correlation analysis showed that in rainy season NDVI had a high grey correlation with Anopheles density and malaria incidence rate. The grey correlation analysis showed that in rainy season the grey degree of NDVI correlated with Anopheles. Minimus density was 0.730, and 0.713 with Anopheles sinensis density, and 0.800 with malarial incidence rate. Conclusion Remote sensing NDVI can serve as a sensitive evaluation index of Anopheles density and malaria incidence rate. [ABSTRACT FROM AUTHOR]

Plateau lakes in China are faced with heavy metal contamination. The present study investigated the concentrations, sources, and ecological risks of 11 heavy metals in sediments of Lake Fuxian over the last 100 years. The concentrations of V (124–244 mg/kg), Cr (69.3–127 mg/kg), Cu (59.4–105 mg/kg), Ni (36.0–66.3 mg/kg), and Co (15.4–25.5 mg/kg) significantly decreased in the last 100 years while Cd, Sb, Pb, and Zn had contrary trends. In the last 100 years, correlations between the heavy metals changed in reverse due to the combined influences of lithogenic and anthropogenic sources. In the last 40 years, the lithogenic sources mainly contributed to the concentrations of As, Hg, V, Cr, Co, Ni, and Cu, with the rates of 55 %− 85 %. Moreover, Cd, Sb, Pb, and Zn were mainly affected by anthropogenic sources (e.g., mining activities and human settlement change), with the contribution rates of 53 %− 80 %. The change of stable Pb isotope in the sediment cores indicated that galena mining was the main source of Pb. With increasing anthropogenic activities, there was a possibility of 90 % that a moderate ecological risk might appear in the last 40 years. Among the heavy metals, Cd should attract attention because it contributed 96 % to the combined ecological risk. [Display omitted] • Correlations between heavy metals changed in reverse among three different periods. • Anthropogenic sources obviously accelerated the accumulation of Cd, Pb, Sb, and Zn. • Smelting and mining of galena was the main source of Pb in the lake sediments. • A moderate ecological risk of metals might happen, with the possibility of 90 %. • Cd was the most sensitive heavy metal in evaluating the combined ecological risk. [ABSTRACT FROM AUTHOR]

Lake Fuxian, the largest deep freshwater lake in China, has been suffering from increasing ecological and environmental issues along with the rapid urbanization and industrialization in the past 40 years. To better understand the historical pollution of persistent organic pollutants (POPs) in Lake Fuxian, comprehensive analyses of 209 polychlorinated biphenyl (PCB) congeners and 20 organochlorine pesticides (OCPs) were conducted in two intact sediment cores (Core V1 and Core V2). The total mass concentrations of PCBs ranged from 7.60 to 31.47 ng/g (dry weight basis) and 5.55 to 28.90 ng/g during the period of 1908-2019 in Core V1 and 1924-2019 in Core V2, respectively. PCBs exhibited a consecutive increasing trend from 1940s to 2019 in Core V1. The temporal trend of PCBs in Core V2 basically matched to the history of PCB usage and prohibition in China (increasing from 1940s to mid-1960s, a remarkable drop in mid-1970s, and then increasing until 2019). Moreover, low-chlorinated PCBs were dominant among PCB homologues. Mono-CBs, di-CBs, tri-CBs and tetra-CBs accounted for 86.71 %-98.57 % in sediment segments. The PCB sources included unintentional emission and atmospheric deposition, as well as biological transformation. The total mass concentrations of OCPs ranged from 0.74 to 3.82 ng/g in Core V1 and 0.35 to 2.23 ng/g in Core V2, respectively. Similar trend was observed in the two sediment cores with peaks in the early 1990s. The predominant OCPs were γ-hexachlorohexane (γ-HCHs), dieldrin and p,p'-DDD. The ecological risks posed by PCBs and p-p'-DDD in Lake Fuxian were relatively low. In contrast, dieldrin might pose a potential threat to exposed organisms and apparently adverse ecological effects were caused by γ-HCH. This study will provide important baseline information on historical POPs contamination of Lake Fuxian., Competing Interests: Declaration of competing interest The authors, Xuexin Han, Lei Xu, Aixin Deng, Peng Xing and Yan Xu declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the review of the manuscript entitled “Centurial deposition records of polychlorinated biphenyls and organochlorine pesticides in sediment cores from a plateau deep-water lake of China: Significance of anthropogenic impacts, transformation signals and ecological risks revealed by full congener analysis”., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Autophagy plays a pivotal role in the progression and management of colorectal cancer (CRC). Recently, numerous articles focusing on the role of autophagy in CRC have emerged. The present study was conducted to provide a comprehensive analysis of the current state and changing trends in the relationship of autophagy and CRC over the past 20 years., Methods: The Web of Science Core Collection (WOSCC) was utilized to extracted all publications with respect to autophagy and CRC during 2002-2021. The contributions of various countries/regions, institutions and journals in this field were analyzed, moreover, research hotspots and promising future trends predicted through keywords were identified by the online platform of bibliometrics, CiteSpace and VOSviewer., Results: A total of 2418 related publications from 2002 to 2021 were identified and collected. China occupied first place with respect to the number of publications, followed by the USA and South Korea. Shanghai Jiao Tong University published the most papers in this field. Most publications were published in Oncotarget. Additionally, analysis of the keywords identified 4 clusters with various research focuses: "mechanism-related research", "clinical-related research", "tumorigenesis research" and "chemotherapy-related research". The three latest hot keywords in this field were epithelial-mesenchymal transition (EMT), promote and invasion., Conclusions: The number of publications and research interest on autophagy and CRC are increasing annually, and the USA had prominent academic positions in the field. Shanghai Jiao Tong University represents a high level of research and the latest progress in this field can be tracked at Oncotarget. Throughout the research history of autophagy and CRC in the past 20 years, previous studies have mainly concentrated on apoptosis and drug resistance in tumor cells, while EMT in regulating tumorigenesis and development of clinical drugs that inhibit tumor invasion through autophagy may be novel hotspots in the future., Competing Interests: The authors declare no conflict of interest., (© 2022 The Author(s). Published by IMR Press.)

The generation of organic matter (OM) occurs synchronously with phytoplankton growth. Characterization of the generated particulate and dissolved OM during algal blooms in eutrophic lakes is crucial for better understanding the carbon cycle but remains limited. We speculate that sediments play a critical role in the biogeochemical transformation of OM derived from algal blooms in shallow lakes. In this study, changes in OM quantity and quality and the concentrations of biogenic elements (nutrients and metals) during algal blooms, were studied in situ in a shallow eutrophic lake (Lake Chaohu, China). Two enclosure treatments in the presence and absence of sediments were compared, and the cause-effect relationships among sediment, nutrients, metals, phytoplankton, particulate OM (POM), and dissolved OM (DOM) were revealed by a partial least square-path model (PLS-PM). The results showed that the changes in nutrients and metals concentrations over time were consistent with that of chlorophyll a (Chl a), and at the end of the treatment, the concentrations of Chl a, nutrients, and metals in Treatment S (with sediments) were approximately 3-5 times of those in Treatment N (without sediments). The high concentration of Chl a in Treatment S resulted in a high quantity of POM, which showed low molecular weight, low humification, and was enriched in protein-like components (∼ 70%). For DOM, the quantity increased after the decrease in POM, and DOM quality showed a significantly higher abundance of humic-like components and a higher molecular weight than POM did. The PLS-PM results showed that the significant positive effects of sediment on nutrients, metals, phytoplankton, POM, and DOM were 0.28, 0.37, 0.28, 0.25, and 0.25, respectively, suggesting that sediment had an important role in the biogeochemical cycles of these substances. The significant negative relationship between POM and DOM (-0.62) and the distinct difference in POM and DOM quality implied the efficient transformation of the freshly generated OM to those with a higher molecular weight, higher humification, and potentially refractory. Our results depicted the quick biogeochemical transformation of nutrients, metals, and the potential formation of refractory organic carbon in water column, as driven by the couple of the algae pump with the microbial carbon pump., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Introduction and Hypothesis: The aim of this study was to compare the frequency of metabolic syndrome (MetS) in patients with and without interstitial cystitis/bladder pain syndrome (IC/BPS)., Methods: This case-control study evaluated the indicators of MetS in 287 females with IC/BPS and in 287 females without IC/BPS in West China Hospital between January 2010 and January 2020. Then, the number of voids per day, frequency of night urination, O'Leary-Sant Interstitial Cystitis Symptom/Problem Index, and visual analog scale were examined in the two groups., Results: Based on both the National Cholesterol Education Program Adult Treatment Panel III recommendations and the International Diabetes Federation criteria, the distribution of MetS was statistically higher in patients with IC/BPS than in the control group, with 34.8% vs 17.8% (P < 0.0001) and 34.2% vs 20.9% (P = 0.0005), respectively. Regarding symptom scores, the IC/BPS group demonstrated significantly higher scores than the control group in all aspects (P < 0.0001). More patients with anxiety (P < 0.0001), insomnia (P < 0.0001), hypertension (P = 0.0001), and diabetes mellitus (P = 0.017) were observed in the IC/BPS group. Moreover, the findings indicated that patients with IC/BPS had a higher BMI (P = 0.0001) and larger waist circumference (P = 0.0001). Blood tests presented a significantly higher level of fasting glycemia, serum cystatin-C, and triglycerides in patients with IC/BPS. Furthermore, higher ORs for the occurrence of MetS among cases were observed, although this was not statistically significant., Conclusions: MetS frequency was relatively high in patients with IC/BPS. Further research is needed to understand the common pathophysiologic mechanism of IC/BPS and MetS.

To date, little is known about the diazotrophs in freshwater ecosystems. In this study, we examined the diversity, abundance, and distribution of the diazotrophic community in the deep oligotrophic Lake Fuxian using high-throughput sequencing and quantitative polymerase chain reaction of nifH genes. Our results showed that the diazotrophs in Lake Fuxian were diverse and were distributed among Proteobacteria, Planctomycetes, Cyanobacteria, Verrucomicrobia, Bacteroidetes, Chloroflexi, and other unclassified environmental sequences. For the first time, it is found that Bacteroidetes and Planctomycetes harbor diazotrophs in freshwater ecosystems. The diazotrophic community compositions were significantly different between the littoral and pelagic zones in the surface layer, and they also changed dramatically along the vertical profile. High diazotrophic abundance and diversity were mostly observed in the surface littoral zone, and overall, a significant relationship between nifH gene richness and abundance was observed. The water turbidity, nitrite, and phosphorus were the most important factors explaining the spatial changes in diversity and abundances of this important functional group. The two most dominant operational taxonomic units belonging to Betaroproteobacteria and Planctomycetes demonstrated opposite distribution patterns in abundance that were driven by non-overlapping environmental factors. This study is by far the first to uncover the high diversity and intra-lake heterogeneity of diazotrophs in a freshwater lake and illuminate the controlling factors. It provides the probability of the co-occurrence of N 2 fixation and N-loss in particles.

The growth and reproduction of shelterbelt plants in arid regions is mainly limited by water availability, which can be alleviated by drip irrigation. We measured water use efficiency (WUE), leaf gas exchange and carbon isotope composition of Tamarix ramosissima in shelterbelt and natural communities in south fringe of Takelamakan Desert to investigate water use efficiency and photosynthetic properties of T. ramosissima differed in water sources. Compared to natural community, T. ramosissima in the drip irrigation community had low water potential due to irrigation and soil salinity. For natural community, T. ramosissima had lower predawn and midday water potential than other plants, indicating that T. ramosissima suffered serious water stress. The net photosynthe-tic rate (P n ), stomatal conductance (g s ), intercellular carbon dioxide concentration (C i ) and maximum photosynthesis rate (P n max ) of T. ramosissima in the drip irrigation community were significantly lower than that in the natural community, indicating the photosynthesis of T. ramosissima in the drip irrigation community was weaker. Compared to the natural community, T. ramosissima in the drip irrigation community had higher long-term water use efficiency, which was related to salt stress caused by irrigation. We concluded that the current irrigation model could meet the water needs of shelterbelt plants. However, the technical defects and soil salt accumulation might affect long-term stability of the shelterbelt community.

Purpose: The aim of this study was to evaluate the cost-effectiveness of radiofrequency catheter ablation (RFCA) compared with cryoballoon (CB) ablation in the treatment of patients with paroxysmal atrial fibrillation (PAF) from the payer's perspective in China., Methods: We constructed a cohort model, combining a 12-month decision-tree model with a lifetime Markov state-transition model, in a hypothetical cohort of patients with drug-refractory PAF managed with either RFCA or CB ablation, to compare the cost-effectiveness of the 2 procedures. Data related to clinical outcomes and costs in this model were obtained from a retrospective 12-month follow-up study in patients in China and from related literature. The incremental cost-effectiveness ratio (ICER) over a 10-year time period was calculated and compared against the willingness-to-pay (WTP) threshold. We used a 1-way sensitivity analysis and a probabilistic sensitivity analysis (PSA) to access the structural uncertainty and the parameter uncertainty, respectively., Findings: Over a 10-year time horizon, the total costs per patient of RFCA and CB ablation were ¥98,164.04 (US $15,339.57; €13,058.94) and ¥107,542.37 ($16,805.07; €14,306.55), respectively, and quality-adjusted life-years (QALYs) gained were 5.47 and 5.43, respectively. The ICER ratio was -¥224,365.01 (-$35,060.32; -€29,847.68) per QALY, indicating that RFCA is associated with greater QALYs and lower costs than CB ablation. The 1-way sensitivity analysis demonstrated that the model results were most sensitive to the odds ratio of the atrial fibrillation recurrence within 12 months in the RFCA group versus the CB ablation group, the cost of RFCA, and the perioperative stroke risk with RFCA. According to the results of the PSA, RFCA was associated with a high probability of being cost-effective (99.48%) compared with CB ablation at a WTP threshold of ¥161,940 ($25,305.50; €21,543.17) per QALY., Implications: Our analysis indicates that RFCA is cost-saving compared with CB ablation in the treatment of patients with PAF in China, based on better QALYs and lower costs over a 10-year time horizon, from the payer's perspective., (Copyright © 2018. Published by Elsevier Inc.)

Background and Purpose: Ischemic stroke (IS) is the main cause of mortality and disability among the old people in China and is a multifactorial disease influenced by many factors including genetic factors like the allele for CYP 2J2. It has been demonstrated that CYP2J2 polymorphisms alter the transcriptional activity. However, studies on the association between CYP2J2-50G/T polymorphism and IS have reported conflicting results. Thus, our study aimed to examine the association between 4 variants in the CYP2J2 gene and the risk of IS and its subtypes, in the Chinese population., Materials and Methods: In this study, genotyping was performed by using polymerase chain reaction (PCR) sequencing for 202 IS patients and 206 age- and sex-matched controls. Odds ratios (ORs) and confidence interval (CI) were estimated by multivariate logistic regression and PCR results were confirmed by DNA sequencing. A meta-analysis was conducted to evaluate the association of CYP2J2-50G>T polymorphism with the risk of IS in Chinese population by calculating pooled OR., Results: We found this polymorphism was significantly associated with IS (17.82% vs. 10.68%, P = 0.039). Multiple logistic regression analysis revealed that GT genotype was associated with a significantly high risk of IS (OR = 2.32, 95% CI: 1.21-4.45, P = 0. 011) after adjustment for other confounding factors such as hypertension, diabetes, heart disease, smoking habit, family history, triglyceride and low-density lipoprotein levels. We also found a significant association of GT genotype with small artery occlusion (SAA) (P < 0.05; OR = 2.22; 95% CI: 1.043-4.72). Meta-analysis results also showed that the GT genotype carriers had a negative effect on the risk of IS in Chinese population with overall OR of 1.40 (95% CI: 1.06-1.84)., Conclusion: The findings of the present study suggested that polymorphism in -50G/T position of CYP2J2 gene might be a risk factor for IS in Chinese population. Further large prospective studies were required to confirm these findings.

Bacterial strain THMBR28(T) was isolated from decomposing algal scum that was collected during an algal bloom in Taihu lake, China. Cells of strain THMBR28(T) were Gram-staining-positive, facultatively anaerobic and rod-shaped. Growth was observed at 20-45 °C (optimum, 30 °C), at pH 5.0-9.5 (optimum, pH 6.5-7.5), and in the presence of 0-1.0% (w/v) NaCl (optimum, 0.5%). Strain THMBR28(T) contained MK-7 as the major menaquinone and iso-C15 : 0 as the major cellular fatty acid. The polar lipid profile contained phosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine and six unidentified polar lipids. The diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. The DNA G+C content was 57.6 mol% (Tm). Phylogenetic analysis of 16S rRNA gene sequences showed that strain THMBR28(T) belonged to the genus Tumebacillus, most closely related to Tumebacillus ginsengisoli DSM 18389(T) (95.0%) and Tumebacillus permanentifrigoris Eur1 9.5(T) (93.4%). Based on phylogenetic and phenotypic characterization, it is concluded that strain THMBR28(T) represents a novel species of the genus Tumebacillus, for which the name Tumebacillus algifaecis sp. nov. is proposed, with THMBR28(T) ( = CGMCC 1.10949(T) = NBRC 108765(T)) as the type strain.

Aims: Transient ST-T elevation (STE) is a rare complication that occurs during transseptal catheterization. This study aims to delineate the incidence and characteristics of transient STE during transseptal catheterization for atrial fibrillation (AF) ablation., Methods and Results: Consecutive patients who underwent fluoroscopy-guided transseptal catheterization for circumferential pulmonary vein radiofrequency ablation in Beijing An Zhen Hospital from January 2006 to January 2013 were enrolled in this study. Out of 2965 patients with a total of 3452 transseptal catheterization procedures, 13 patients (0.38%, mean age 57 ± 8, 6 female, 12 paroxysmal AF, mean left atrial diameter 35.4 ± 3.8 mm) had STE. ST-T elevation occurred after transseptal puncture in 10 patients and after pulmonary vein venography in three patients. Systolic blood pressure (129 ± 10 vs. 104 ± 20 mmHg, P < 0.001), diastolic blood pressure (78 ± 6 vs. 64 ± 11 mmHg, P < 0.001), and heart rate (83 ± 19 bpm vs. 64 ± 23 b.p.m., P = 0.022) significantly decreased when STE occurred. Eleven patients complained of chest pain, one patient complained of dizziness, and one patient had no symptoms. Patients recovered in about 4.6 min (2-10 min) with dopamine or fast saline drip. Catheter ablation of AF was completed in all the 13 patients without sequelae or other complications. Four of the 13 patients (30.8%) had recurrence of AF after a mean follow-up of 21.7 months., Conclusion: ST-T elevation is a rare complication associated with transseptal catheterization without sequelae. Catheter ablation of AF could be safely completed in these patients., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)

A survey was carried out in the Yellow Sea and the East China Sea from March 17 to April 06 of 2011. Dissolved CH4 in various depths were measured and sea-to-air fluxes were estimated. Methane concentrations in surface and bottom waters ranged between 2.39-29.67 nmol x L(-1) and 2.63-30.63 nmol x L(-1), respectively. Methane concentrations in bottom waters were slightly higher than those in surface waters, suggesting the existence of methane source in bottom waters or sediments. The horizontal distribution of dissolved CH4 showed a decrease from the river mouth to the open sea, and was influenced by the freshwater discharge and the Kuroshio intrusion. Surface methane saturations ranged from 93%-1 038%. Sea to air CH4 fluxes were (2.85 +/- 5.11) micromol x (m2 x d)(-1) (5.18 +/- 9.99) micromol x (m2 x d)(-1) respectively, calculated using the Liss and Merlivat (LM86), the Wanninkhof (W92) relationships and in situ wind speeds, and estimated emission rates of methane from the East China Sea and the Yellow Sea range from 7.05 x 10(-2) - 12.0 x 10(-2) Tg x a(-1) and 1.17 x 10(-2) - 2.20 x 10(-2) Tg x a(-1), respectively. The Yellow Sea and East China Sea are the net sources of atmospheric methane in the spring.

Macrophytes play an important role in structuring aquatic ecosystems. In this study, we explored whether macrophyte species are involved in determining the bacterioplankton community composition (BCC) in shallow freshwater lakes. The BCC in field areas dominated by different macrophyte species in Taihu Lake, a large, shallow freshwater lake, was investigated over a 1-year period. Subsequently, microcosm experiments were conducted to determine if single species of different types of macrophytes in an isolated environment would alter the BCC. Denaturing gradient gel electrophoresis (DGGE), followed by cloning and sequence analysis of selected samples, was employed to analyze the BCC. The DGGE results of the field investigations indicated that the BCC changed significantly from season to season and that the presence of different macrophyte species resulted in lower BCC similarities in the summer and fall. LIBSHUFF analysis of selected clone libraries from the summer demonstrated different BCCs in the water column surrounding different macrophytes. Relative to the field observations, the microcosm studies indicated that the BCC differed more pronouncedly when associated with different species of macrophytes, which was also supported by LIBSHUFF analysis of the selected clone libraries. Overall, this study suggested that macrophyte species might be an important factor in determining the composition of bacterial communities in this shallow freshwater lake and that the species-specific influence of macrophytes on BCC is variable with the season and distance.

The Legionella spp. are ubiquitous in aquatic environment and could cause certain risks on human health. In order to investigate the distribution and diversity of Legionella spp. in Lake Taihu during winter time, water samples were collected from 32 sites of the whole lake in February 2010. The presence of Legionella spp. was screened by nested-PCR and their phylogenetic diversity was determined by denaturing gradient gel electrophorese (DGGE) and sequencing analysis of excised DGGE bands. The Legionella spp. was detected from 21 out of 32 sites in particle-associated bacterial samples and 11 out of 32 sites in free-living bacterial samples, which accounted for 65.63% and 34.38% of each type of bacteria, respectively. In total, 40 and 36 unique bands were identified among those particle-associated and free-living bacterial DGGE profiles, respectively. Community characteristic indices of different euthrophic areas showed that the diversity of Legionella spp. in mild eutrophic areas was higher than that in the moderate eutrophic areas. In total, thirty-four DGGE bands were excised and sequenced, which could be classified into 12 OTUs by 97% similarity. Among all the sequences, three showed a high similarity with two pathogenic Legionella species Legionella feeleii and Legionella longbeachae. This revealed potential healthy risks to the people lived around the Lake Taihu.

Mesocosm experiments were carried out to examine the potential impacts of Microcystis blooms on microbial eukaryotic community composition (MECC). Four treatment additions of differing Microcystis spp. biomass were performed in enclosures, as indicated by chlorophyll a concentrations from 15 to 3217 μg L(-1) in the water column. Dialysis bags were used in enclosures to measure MECC dynamics without influence from predation and irradiance. Samples were taken on days 0, 1 and 4 for MECC analysis, based on changes in the chemical parameters during simultaneous monitoring. The MECC were determined by terminal restriction fragment length polymorphism (T-RFLP), followed by cloning and sequencing of 18S rRNA genes of selected samples. T-RFLP and clone library analysis revealed that MECC in enclosures and dialysis bags shifted strongly during Microcystis spp. decomposition. Members belonging to fungi became the dominant organisms in enclosures with a high biomass of Microcystis spp. Canonical correspondence analysis indicated that temporal changes in MECC were mostly related to changes in the pH and concentrations of dissolved oxygen and dissolved organic carbon, which were induced by the addition of Microcystis spp. The experiment suggests that accumulation of Microcystis biomass can strongly impact MECC, and there might be a saprophytic association between fungi and the decomposition of Microcystis biomass., (© 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.)

Based on the expression of estrogen receptor (ER), progesterone receptor (PR) and HER2/neu (HER2), breast cancer is classified into several subtypes: luminal A (ER+ and/or PR+, HER2-), luminal B (ER+ and/or PR+, HER2+), HER2-overexpressing (ER-, PR-, and HER2+) and triple-negative (ER-, PR-, and HER2-). The aim of this case-control study is to determine reproductive factors associated with breast cancer subtypes in Chinese women. A total of 1,417 patients diagnosed with breast cancer in the First Affiliated Hospital, China Medical University, Shenyang, China between 2001 and 2009 and 1,587 matched controls without a prior breast cancer were enrolled. Personal interviews were conducted to obtain information on reproductive characteristics and clinical history. Relationships between the factors and the subtypes of breast cancer were examined using logistic regression to compute odds ratios (OR) and 95% confidence intervals (CI). Notably, luminal A (50.0%) was the most prevalent subtype relative to luminal B (15.10%), HER2-overexpressing (10.87%) and triple-negative (23.08%). Menarche at an early age was associated with a reduced risk of luminal A (OR, 2.35; 95% CI, 1.45-3.81). Breastfeeding protected parous women from any subtype of breast cancer. Postmenopause and spontaneous abortion were inversely associated with the risk of luminal tumors. By contrast, multiparity, family history of breast cancer and induced abortion increased the risk of breast cancer. Collectively, our findings suggest that reproductive factors such as age at menarche, parity, breastfeeding, menopausal status and abortion history have different effects on the subtypes of breast cancer in Chinese women.

Based on the ideology of macro environmental economics, a function of environmental pressure represented by pollutant emission was built, and the relative importance of the driving factors in the dynamic changes of the relationships between economic growth and environmental pressure in Gansu Province in 1990 - 2005 was analyzed by using structural decomposition analysis (SDA) model combining with 'refined Laspeyres' method. In the study period, the environmental pressure in the Province was mainly caused by the emission of waste gases and solids in the process of economic growth, and showed a rapid increasing trend at the late stage of the period. Population factor had less impact on the increase of this environmental pressure, while economic growth factor had obvious impact on it. Technological progress did mitigate, but could not offset the impact of economic growth factor, and the impacts of economic growth and technological factors on the environmental pressure differed with the kinds of pollutants.

Objective: To investigate the molecular mechanism of carbapenem resistance in the clinical isolates of Acinetobacter baumannii from Xi'an and their profile of carbapenemase production., Methods: A total of 146 Acinetobacter baumannii strains were isolated from 6 general hospitals in Xi'an. Antimicrobial susceptibility test was performed for all the strains, followed by detection of imipenem resistance using E-test for metallo-beta-lactamase (MBL) and NaCl inhibition test for OXA type carbapenemase. Bla(OXA-23)and bla(OXA-58) were amplified by PCR, and the positive products were sequenced., Results: From the collected strains, 15 non-repetitive imipenem-resistant Acinetobacter baumannii strains were identified, among which 14 yielded negative results in E-test for MBL production. All the resistant strains showed increased sensitivity to imipenem after NaCl inhibition, suggesting the presence of carbapenemase production. Eleven of the strains harbored OXA -23 type gene and 1 harbored OXA -58 type gene. The concordance rate of the results by NaCl inhibition test and PCR was 85.7%., Conclusions: Production of OXA-type carbapenemase is the most important reason for carbapenem resistance in Acinetobacter baumannii in Xi'an. The OXA-58 type gene is a novel carbapenemase genotype in China. NaCl inhibition test is a convenient and cost-effective method for detecting carbapenemase in Acinetobacter baumannii.

Aims: The aim of this study was to identify the impact of obstructive sleep apnoea (OSA) on recurrence after catheter ablation of paroxysmal atrial fibrillation (AF)., Methods and Results: One hundred and seventy-eight consecutive patients with paroxysmal AF who underwent index circumferential pulmonary vein (PV) isolation were prospectively enrolled. The patients were divided into high risk (HR group) and low risk (LR group) for OSA group with Berlin questionnaire. Of the 178 patients, 104 (58.4%) were in the HR group and 74 (41.6%) were in the LR group. After a mean follow-up of 344 +/- 137 (91-572) days, 44 patients (24.7%) experienced recurrence, and the recurrence rate did not differ between the HR (25.0%) and LR groups (24.3%, P = 0.855). Cox analysis revealed that PV isolation was the only independent predictor of recurrence (hazard ratio 5.11, 95% confidence interval 1.42-18.47, P = 0.013). There was no significant difference in the incidence of complications between the HR and LR groups (2.9 vs. 1.9%, P = 0.729)., Conclusion: The recurrence rate and incidence of complications did not differ in patients with different risk profiles for OSA. The presence of OSA should not lower the decision threshold to choose an ablative procedure in paroxysmal AF.

To investigate the effects of aquatic plants on ammonia-oxidizing bacteria (AOB) at their root zones, four species of aquatic plants were selected, Phragmites communis, Typha angustifolia L., Potamogeton crispus L., and Limnanthemun nymphoides, which were widely used in ecological restorations. AOB in the samples were enumerated by most-probable-number (MPN) method. Nested polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) procedures were performed with ammonia oxidizer-selective primers. Main DGGE bands were excised from the gel and sequenced for phylogenetic affiliation. Results indicate that AOB densities are always higher at the root zones of emergent plants (Phragmites communis 2.8 x 10(5) cells/g and Typha angustifolia L.4.3 x 10(5) cells/g) than those of submerged and floating-leaved plant (Potamogeton crispus L. 9.3 x 10(4) cells/g and Limnanthemun nymphoides 7.7 x 10(4) cells/g). At the root zones, the oxidation-reduction potential is above zero and NH4+ concentration is lower than it in the bare surface sediment. Fourteen major bands were recovered from the DGGE gel, re-amplified and sequenced. Although the identified bands have their respective similar sequences in GenBank, most of them are related to Nitrosomonas-like. This type of bacteria would play an important role of nitrogen cycle in lake sediment after ecological restoration.

The methods of DGGE and cloning/sequencing were used to study the diversity and community structures of small planktons (0.8 - 20 microm) in different areas of Lake Taihu. DGGE indicated that there were markly various fingerprints in different areas and the diversities were higher in areas with low trophic status than those with relatively high trophic status. There were 23, 24 DGGE bands in East Taihu and Gonghu Bay, respectively (Shannon index were 3.135 and 3.178) and 18 bands in both Meiliang Bay and Wuli Bay (Both shannon index were 2.890). The result of cloning/sequencing indicated that there was a high diversity of small planktons in Lake Taihu and most of them phototrophic flagellate, heterotrophic flagellate, ciliate and fungi. There were various community structures in the three different clone libraries. In Meilang Bay, 28.6% OTUs(operational taxonomic unit)belonged to heterotrophic flagellate, followed by Cryptophyta (22.9%) and Chrysophyta (14.3%). In Central Lake, 25.7% OTUs belonged to Chrysophyta, followed by heterotrophic flagellate (20.0%) and Cryptophyta (14.3 %). In East Taihu, ciliates were the dominant group and only a few heterotrophic flagellates (40.9%) were detected. In addition, fungi were relatively abundant (12.2%) in this area.

Objective: To study the relationship of remote sensing normalized differential vegetation index (NDVI) to Anopheles density and malaria incidence rate., Methods: Data of monthly average climate, environment, Anopheles density and malaria incidence rate, and remote sensing NDVI were collected from 27 townships of 10 counties in southeastern Yunnan Province from 1984 to 1993. The relationship of remote sensing ecological proxy index, NDVI, to Anopheles density and malaria incidence rate was studied by principal component analysis, factor analysis and grey correlation analysis., Results: The correlation matrix showed that NDVI highly correlated with Anopheles density in 4 townships of Mengla, Jinghong, and Yuanjiang counties, but in other 23 townships the relationship was not clear. Principal component and factor analyses showed that remote sensing NDVI was the representative index of the first principal component and the first common factor of Anopheles density evaluation. Grey correlation analysis showed that in rainy season NDVI had a high grey correlation with Anopheles density and malaria incidence rate. The grey correlation analysis showed that in rainy season the grey degree of NDVI correlated with Anopheles. Minimus density was 0.730, and 0.713 with Anopheles sinensis density, and 0.800 with malarial incidence rate., Conclusion: Remote sensing NDVI can serve as a sensitive evaluation index of Anopheles density and malaria incidence rate.