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The matrix protein (M1) of influenza A virus plays an important role in replication, assembly, and budding. A previous study found that aspartic acid (D) at position 30 and alanine (A) at position 215 of M1 contribute to the high pathogenicity of H5N1 viruses in mice, and double mutations of D to asparagine (N) at position 30 (D30N) and A to threonine (T) at position 215 (A215T) in M1 dramatically attenuate H5N1 viruses in mice. However, the underlying mechanisms by which these M1 mutations attenuate the virulence of H5N1 viruses are unknown. Here, we found that the amino acid mutation A215T eliminates the SUMOylation of M1 by reducing its interaction with the host SUMO1 protein, significantly reducing the stability of M1, slowing the export of the M1-vRNP complex from the nucleus to the cytoplasm, and reducing viral replication in MDCK cells. We further found that the D30N mutation in M1 alters the shape of progeny viruses from filamentous to spherical virions. Our findings reveal an essential role for M1 215A SUMOylation and M1 30D-related filamentous morphology in the pathogenesis of avian influenza viruses, which could be targeted in novel antiviral drug designs. IMPORTANCE Identification of the pathogenic mechanism of highly pathogenic avian influenza viruses in mammals is helpful to develop novel anti-influenza virus strategies. Two amino acid mutations (D30N and A215T) in M1 were found to collectively attenuate H5N1 influenza viruses in mice, but the underlying mechanism remained unknown. This study found that the A215T mutation significantly decreases the SUMOylation of M1, which in turn attenuates the replication of H5N1 virus in mammalian cells. The D30N mutation in M1 was found to change the virion shape from filamentous to spherical. These findings are important for understanding the molecular mechanism of virulence of highly pathogenic avian influenza viruses in mammals.
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Virus da Influenza A Subtipo H5N1/fisiologia , Virus da Influenza A Subtipo H5N1/patogenicidade , Infecções por Orthomyxoviridae/virologia , Proteínas da Matriz Viral/metabolismo , Replicação Viral , Transporte Ativo do Núcleo Celular , Animais , Núcleo Celular/metabolismo , Cães , Virus da Influenza A Subtipo H5N1/metabolismo , Virus da Influenza A Subtipo H5N1/ultraestrutura , Células Madin Darby de Rim Canino , Camundongos , Mutação , Infecções por Orthomyxoviridae/metabolismo , Estabilidade Proteica , Ribonucleoproteínas/metabolismo , Sumoilação , Proteínas da Matriz Viral/genética , Vírion/ultraestrutura , Virulência/genética , Replicação Viral/genéticaRESUMO
Repeated red mud (RM) stockpile accidents have sounded an alarm that a healthy alumina industry requires secure RM disposal. Unfortunately, the flawed mechanical properties of RM-based alkali-activated materials (RM-AAM) with bulk RM incorporation have impeded the ideal large-volume, low-risk utilization of RM and the provision of sustainable binders for communities. By reviewing a wide range of studies, this work provides insights into establishing a mature synthesis technique for optimizing the mechanical properties of RM-AAM. Brief evaluations of the nature and the current RM-AAM synthesis systems were conducted. The following emphasis is on addressing the influence characteristics and mechanisms of the known RM-AAM synthesis factors, including RM pre-activation, precursor composition, alkali activator property, preparation process treatment, and curing regime, on the mechanical properties of RM-AAM. Further optimization suggestions on each aspect of the synthesis process and the final complete set of synthesis technology that could best enhance the mechanical properties of RM-AAM were proposed. The general limitations of current research on developing a mature RM-AAM synthesis technique were identified, along with possible solutions.
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Álcalis , Óxido de AlumínioRESUMO
The transport of excess nutrients into freshwater systems constitutes a serious risk to both water quality and aquatic health. Vegetated buffer zones (VBZs) next to waterways are increasingly used in many parts of the world to successfully intercept and eliminate pollutants and other materials in overland flow, especially in warm or temperate regions. The major processes for the retention of pollutants in VBZ are microbial degradation, infiltration, deposition, filtration, adsorption, degradation, assimilation, etc. The effectiveness of the VBZ relies on several environmental factors, including BZ width, runoff intensity, slope, soil texture, temperature, vegetation type, etc. Among the reported factors, cold weather possesses the most detrimental impact on many of the processes that VBZ are designed to carry out. The freezing temperatures result in ice formation, interrupting biological activity, infiltration and sorption, etc. In the last twenty years, burgeoning research has been carried out on the reduction of diffuse nutrient pollution losses from agricultural lands using VBZ. Nonetheless, a dearth of studies has dealt with the problems and concerns in cold climates, representing an important knowledge gap in this area. In addition, the effectiveness of VBZ in terms of nutrient removal abilities varies from -136% to 100%, a range that reveals the incertitude surrounding the role of VBZ in cold regions. Moreover, frozen soils and plants may release nutrients after undergoing several freeze-thaw cycles followed by runoff events in spring snowmelt. This review suggests that the management and design of VBZ in cold climates needs close examination, and these systems might not frequently serve as a good management approach to decrease nutrient movement.
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Poluentes do Solo , Poluentes Químicos da Água , Clima Frio , Agricultura , Poluentes do Solo/análise , Fósforo , Poluentes Químicos da Água/análise , Solo , Nutrientes , Nitrogênio/análiseRESUMO
Base flow (BF) is harder to predict than other hydrological signatures. The lack of hydrologically relevant information or adequately broad spectrum of typically selected catchment attributes (particularly landscape and topography) hinders the explanatory power. Our goals were to identify the most influential controls on base flow spatially and temporally and to elucidate the response relationships. Base flow in 19 semi-arid sub-watersheds was separated by digital filtering. One hundred and fourteen sub-watershed attributes were related to base flow using random forest regression. The main results were as follows: (1) Annual BF significantly declined since 1999 due to decreased precipitation, increased air temperature, afforestation, urban expansion, and increasing water consumption. Annual base flow index (BFI), varying between 0.319 and 0.695, showed less noticeable temporal trends. (2) Precipitation (P) and underlying carbonate rocks primarily controlled the spatial variation of annual BF and total flow (TF), with the impacts being positive. Landscape was less influential. After the abrupt runoff decline, landscape composition rather than configuration exerted greater impacts on spatial BF and TF, and the importance of forest increased, whereas landscape configuration was decisive for BFI during the whole observation period. The absence of significant links between landscape configuration and water quantity may result from a scale issue. Concave profile curvatures were found to be topographic variables more important than slopes. The impact of soil was the least. This study would benefit the selection of catchment attributes and spatial extents to quantify these attributes in building BF predicting models in future studies.
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Monitoramento Ambiental , Solo , HidrologiaRESUMO
[This corrects the article DOI: 10.1371/journal.ppat.1004508.].
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Elevated particles and phosphorus washed from road-deposited sediment (RDS) are noteworthy causes of eutrophication in urban water bodies. Identifying how urban elements (e.g., dwellings, roads) spatially influence RDS and the associated phosphorus can help pinpoint the primary management areas for RDS pollution and therefore effectively mitigate this problem. This study investigated spatial influence of urban elements on RDS build-up load and phosphorus load in Hanyang district of Wuhan city in central China. Bayesian Networks (BNs), combined with geographical detector (Geodetector) and correlation analysis, were applied to quantify spatial association between kernel density of urban elements, RDS build-up load and phosphorus load in RDS. Results showed that (1) areas with higher density of factories related elements usually had elevated level of RDS build-up load, aluminum-bound phosphorus (Al-P), occluded phosphorus (Oc-P), organophosphorus (Or-P). Higher load of RDS associated iron-bound phosphorus (Fe-P) and apatite phosphorus (Ca-P) usually occurred where dwellings, catering, and entertainment related elements were concentrated. (2) Urban elements mainly showed positive correlation with RDS build-up load, Fe-P, Ca-P, De-P (detrital apatite phosphorus), while they chiefly showed negative correlation with Ex-P (exchangeable phosphorus), Al-P, Oc-P, and Or-P. Bus stations, dwellings, and factories related elements had relatively strong determinant power over spatial stratified heterogeneity of RDS and RDS-associated phosphorus. (3) Geodetector and correlation analysis could boost factors filtering and construction of network structures in the process of developing BNs models. The developed BNs resulted in sound prediction of <150 µm RDS build-up load and phosphorus load, given that the prediction accuracy of models ranged from 0.532 to 0.657. These findings demonstrate that urban elements are useful spatial predictors of RDS pollution, and coupling Geodetector and BNs is promising in RDS pollution prediction and supporting urban nonpoint source pollution management.
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Fósforo , Poluentes Químicos da Água , Apatitas/análise , Teorema de Bayes , China , Monitoramento Ambiental , Sedimentos Geológicos/análise , Fósforo/análise , Poluentes Químicos da Água/químicaRESUMO
Rubber dams are widely used in urban rivers for landscape construction and flood control. However, the increased water residence time by dams usually causes phytoplankton accumulation. Developing a greater understanding of the phytoplankton dynamics and the effecting factors is essential for the eutrophication control of dammed rivers. Here, we investigated the variations in biomass and structure of phytoplankton communities along an urban landscape river with 30 rubber dams, and the main controlling factors during a 2-yr field monitoring. The biomass of phytoplankton significantly increased from 12.7 µg/L-Chl a and 1.14 × 107 ind./L-cells at the natural river part above dams to 65.2 µg/L-Chl a and 1.16 × 108 ind./L-cells at the 30th dam on average. There were different dominant taxa of phytoplankton between river sections with and without dams in different seasons. As Bacillariophyta dominated at the natural river part above dams throughout the year, accounting for 64.6% on average, and dominated at the 13th and 30th dams during the cold seasons (69.6% on average). But during the warm seasons, Cyanophyta and Chlorophyta increased obviously in the dammed river sections and became dominant taxa at the 30th dam, accounting for 55.9% and 34.7% respectively. The α-diversity of phytoplankton decreased along the series of dams. While the ß-diversity between river sections with and without dams increased because of species replacement. Redundancy analysis revealed that nutrients, flow velocity and temperature were the main factors influencing the spatial-temporal variation in phytoplankton community structure in this river. High-frequency monitoring data further indicated that phosphorus and discharge explained most of the variations in phytoplankton biomass within the 13th dam impoundment. It suggested that management strategies should focus on reducing the phosphorus input concentration under 0.164 mg/L and increase the discharge higher than 0.64 m3/s during warm seasons, to prevent phytoplankton bloom and further eutrophication problems in this dammed river.
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BACKGROUND: It has been reported that high expression levels of miR-197 can predict coronary artery disease (CAD). Our bioinformatics analysis showed that miR-197 may bind to long non-coding RNA (lncRNA) TONSL-AS1. This study aimed to investigate the role of TONSL-AS1 in CAD. METHODS: This study included 60 CAD patients and 60 healthy controls. Coronary angiography was performed to diagnose CAD. The interaction between TONSL-AS1 and miR-197 was predicted by IntaRNA2.0. Western-blot analysis was performed to illustrate the effect of MTONSL-AS1, miR-197 and BCL2 on human primary coronary artery endothelial cells (HCAECs). Cell migration assay was performed to explore the roles of MTONSL-AS1, miR-197 and BCL2 in regulating cell migration. Cell apoptosis assay was performed to investigate the role of MTONSL-AS1, miR-197 and BCL2 in regulating the apoptosis of HCAECs. RESULT: Significant differences in high-density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), and gensini score were observed in patients with CAD. In addition, TONSL-AS1 was downregulated in CAD. Follow-up study revealed that low expression levels of TONSL-AS1 and high expression levels of miR-197 predicted poor survival of CAD patients. Overexpression experiments showed that TONSL-AS1 and miR-197 had no significant effect on the expression of each other. We speculated that MAFG-AS1 may sponge miR-145. Moreover, overexpression of TONSL-AS1 increased, while overexpression of miR-197 decreased the expression levels of BCL2. Furthermore, overexpression of TONSL-AS1 attenuated the effects of overexpression of miR-197 on migration and apoptosis of HCAECs. CONCLUSIONS: Therefore, the expression of TONSL-AS1 predicted the survival of CAD patients and it sponged miR-197 to inhibit the apoptosis of HCAECs.
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Doença da Artéria Coronariana/metabolismo , Vasos Coronários/metabolismo , Células Endoteliais/metabolismo , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Adulto , Idoso , Apoptose , Estudos de Casos e Controles , Movimento Celular , Células Cultivadas , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Células Endoteliais/patologia , Feminino , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Longo não Codificante/genéticaRESUMO
H9N2 avian influenza viruses sporadically infect humans worldwide. These viruses have also contributed internal genes to H5N1, H5N6, H7N9, and H10N8 viruses, which have been isolated from humans with infections and are a substantial public health threat. To investigate the potential pathogenic mechanism of the H9N2 virus, we performed serial lung-to-lung passage of an avirulent H9N2 avian influenza virus (A/Chicken/Shandong/416/2016 [SD/416]) in mice to increase the pathogenicity of this virus. We generated a mouse-adapted (MA) virus that exhibited increased viral titers in the lungs, caused severe lung damage in mice, and induced body weight loss in mice; however, the avirulent parental virus did not cause any clinical symptoms in infected mice. Global gene expression analysis was performed and indicated that the transcriptional responses of these viruses were distinct. The lungs of mice infected with the MA virus exhibited the downregulation of genes related to innate immunity and ubiquitin-mediated proteolysis, which was not seen in infections with the avirulent parental virus. These data indicated that the MA virus might evade immune surveillance and changed its replication capacity to increase the viral replication level and pathogenicity. Our study demonstrates that host factors play an important role in the adaptive evolution of influenza virus in new hosts.
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Adaptação Fisiológica/genética , Imunidade Inata/genética , Vírus da Influenza A Subtipo H9N2/patogenicidade , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/virologia , Proteólise , Ubiquitina/metabolismo , Animais , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/metabolismo , Inoculações Seriadas , Ubiquitina/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Replicação ViralRESUMO
Watermilfoil (Myriophyllum) is one of the world's most troublesome invasive aquatic weeds. Although current management practices may inhibit its expansion, it also impacts not only the quality of water but habitat deterioration. Therefore, the need for developing highly efficient and low-cost biotechnologies with resource recovery into the agriculture field as a complementary management strategy cannot be overstated. Here, we reviewe the scientific/grey literature to offer readers a precise and panoramic view of the invasive watermilfoil ecology, regional problems, impacts, ecosystem services, and management. In this regard, an in-depth review aimed to assess the potential for reducing non-point source inorganic and organic pollutants using invasive watermilfoil, with the sustainable approaches, while offering other services and mitigating ecological trade-offs is presented. Global distributions, growth, and current progress on the management and utilization of invasive watermilfoil biomass are summarized to develop the aim, which is to convey challenges during the implementation of large-scale weed use. In short, pollutant assimilation in plant and bacterial communities linked to this weed considerably contribute to the reduction and degradation of pollutants from both natural and artificial systems. Although several considerations in recycling and reusing biomass need to be considered, the potential reuse of the harvested material for livestock feed, compost and direct use in farming systems offer an additional strategy to achieve sustainable ecosystem restoration. Further research and development may focus on a more detailed economic modeling approach that integrates the costs (worker's wage, harvesting, transportation, and energy consumption), legal and regulatory barriers, health risks and ecosystem service benefits (biodiversity improvement, and pollutant removal) to holistically evaluate the economic, environmental, and societal value of reusing and recycling this waste material.
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Ecossistema , Poluentes Ambientais , Agricultura , Biodiversidade , BiomassaRESUMO
It is widely acknowledged that dams affect sediment transport and water quality. To support water management of reservoirs, it is useful to explore how the fractions of phosphorus (P) in sediments were changed after the dam was built. The aim of this study was to assess the spatial and temporal trends of the P fractions in sediments from the Miyun Reservoir, a pivotal drinking water supply for Beijing City, the capital of China. Nine surface sediment samples, together with a sediment core, were collected. The concentrations of total P (TP) and their fractions were then determined by using a sequential extraction method. The results showed that the reservoir was classified into three areas spatially based on the TP concentrations, i.e., high (Baihe area), medium (transitional area), and low (Chaohe area) concentrations. The concentrations of iron-bound P (BD-P) and metal oxide-bound P (NaOH-P) were higher in the Baihe and Chaohe regions than those in the transitional area and tended to increase with water depth. Dam construction can lead to the concentrations of P increased in sediments and further increase the potential of internal P loadings. This study revealed the effect of dam construction on sedimentary P accumulation. The results will be helpful in better understanding the mobility and bioavailability of P in the aquatic ecosystem, which aim to achieve a more highly targeted environmental management for this important region.
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Água Potável/química , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Fósforo/análise , Poluentes Químicos da Água/análise , Pequim , China , Ecossistema , Eutrofização , Ferro/análise , Qualidade da Água , Abastecimento de ÁguaRESUMO
Small dams are widely constructed in urban rivers as landscape engineering practice, which increasingly cause eutrophication problems. Phosphorus retention in dammed rivers is a critical factor driving eutrophication, but it is little known in urban landscape river systems controlled by small dams. In this study, we investigated the retention of different phosphorus species along an urban landscape river with 30 rubber dams. We found that 42.5% (7.69 metric tons/yr) of the total phosphorus (TP) was trapped within dams, of which total particulate phosphorus (TPP) retention load accounted for 81.5%. From first river segment BBF-4# to the segments further downstream, the TP retention rate sharply decreased from 47.6% to -8.3%-9.2%, and phosphorus was mainly retained in the uppermost segment of the dammed river. The retention rate of dissolved reactive phosphorus (86.3%) was higher than that of TPP (40.3%) because of biological uptake. Further, with a retention rate of -11.3%, the dammed river was a net source of dissolved organic phosphorus. Different hydrological regimes, due to seasonal events and dam management, greatly influenced phosphorus retention within the dammed river, resulting in higher retention loads in the rainy season than in the dry season, and very low retention loads in the snowmelt season, with 1.48, 0.55 and 0.06â¯t/month, respectively. Our findings imply that management practices should focus on reducing the phosphorus export from the upper watershed and improving the hydrodynamic conditions of the dammed urban landscape river with regard to eutrophication.
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Fósforo/análise , Rios/química , Eutrofização , Diques de Borracha , Estações do Ano , Poluentes Químicos da Água/análiseRESUMO
H9N2 subtype influenza viruses have been detected in different species of wild birds and domestic poultry in many countries for several decades. Because these viruses are of low pathogenicity in poultry, their eradication is not a priority for animal disease control in many countries, which has allowed them to continue to evolve and spread. Here, we characterized the genetic variation, receptor-binding specificity, replication capability, and transmission in mammals of a series of H9N2 influenza viruses that were detected in live poultry markets in southern China between 2009 and 2013. Thirty-five viruses represented 17 genotypes on the basis of genomic diversity, and one specific "internal-gene-combination" predominated among the H9N2 viruses. This gene combination was also present in the H7N9 and H10N8 viruses that have infected humans in China. All of the 35 viruses preferentially bound to the human-like receptor, although two also retained the ability to bind to the avian-like receptor. Six of nine viruses tested were transmissible in ferrets by respiratory droplet; two were highly transmissible. Some H9N2 viruses readily acquired the 627K or 701N mutation in their PB2 gene upon infection of ferrets, further enhancing their virulence and transmission in mammals. Our study indicates that the widespread dissemination of H9N2 viruses poses a threat to human health not only because of the potential of these viruses to cause an influenza pandemic, but also because they can function as "vehicles" to deliver different subtypes of influenza viruses from avian species to humans.
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Variação Genética , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária , Influenza Humana , Animais , Sequência de Bases , Galinhas , China , Cães , Furões , Humanos , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Vírus da Influenza A Subtipo H9N2/patogenicidade , Influenza Aviária/genética , Influenza Aviária/transmissão , Influenza Humana/genética , Influenza Humana/transmissão , Células Madin Darby de Rim Canino , Dados de Sequência Molecular , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologiaRESUMO
Human infection by H7N9 influenza virus was first identified in China in March 2013. As of 12 August 2013, a total of 135 documented cases with 44 fatalities had been reported. Genetic and laboratory analyses of the novel H7N9 viruses isolated from patients indicate that these viruses possess several polymerase gene mutations previously associated with human adaptation and potential pandemic capabilities. However, the function of these mutations in the emergence and pathogenicity of the viruses is not well known. In this study, we demonstrate that the PB2 E627K mutation, which occurs in over 70â% of the H7N9 patient isolates, promotes the replication of H7N9 virus by enhancing PB2 polymerase activity and enhances virulence in mice. Our results show the PB2 E627K mutation has played an important role in this H7N9 influenza outbreak and in the pathogenicity of the H7N9 virus.
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Subtipo H7N9 do Vírus da Influenza A/enzimologia , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Proteínas Mutantes/metabolismo , Mutação de Sentido Incorreto , RNA Polimerase Dependente de RNA/metabolismo , Proteínas Virais/metabolismo , Replicação Viral , Animais , Peso Corporal , Linhagem Celular , Modelos Animais de Doenças , Feminino , Humanos , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , RNA Viral/genética , Análise de Sequência de DNA , Carga Viral , VirulênciaRESUMO
Identification of nonpoint source (NPS) pollution is a great challenge in the North China Plain, which has modified rivers and insufficient data. In this study, a simple and reasonable method was developed to estimate the total nitrogen (TN) load in rural areas of the North China Plain. The method was found to work well and produce results consistent with monitoring data when considering various TN sources and transfer mechanisms. The annual TN loads from rural living, livestock and the farmlands were 121.9 × 10(3), 45.6 × 10(3) and 78.5 × 10(3) kg/yr, respectively. The TN load in the region along the river contributed much more to the NPS pollution than that in areas far from the river, with average TN loads of approximately 3394 and 602 kg km(-2) yr(-1), respectively. Overall, the results indicate that this method is suitable for NPS load estimates in severely disturbed watersheds with insufficient data.
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Nitrogênio , Rios , Poluição da Água , Agricultura , China , Humanos , População Rural , IncertezaRESUMO
Nutrient discharge during storm events is a critical pathway for nutrient export in semi-arid catchments. We investigated nutrient dynamics during three summer storms characterized by different rainfall magnitude in 2012 in a semi-arid catchment of northern China. The results showed that, in response to storm events, nutrient dynamics displayed big variation in temporal trends of nutrient concentration and in nutrient concentration-flow discharge relationships. Nutrient concentrations had broader fluctuations during an extreme storm than during lesser storms, whereas the concentration ranges of the a moderate storm were no broader than those of a smaller one. The different concentration fluctuations were caused by storm magnitude and intensity coupled with the antecedent rainfall amount and cumulative nutrients. Correlation coefficients between nutrient concentrations and flow discharge varied from positive to negative for the three different events. There were no consistent hysteresis effects for the three different events, and no hysteresis effects were observed for any of the variables during the moderate storm (E2). Our findings provide useful information for better understanding nutrient loss mechanisms during storm events in semi-arid areas of a monsoon climate region.
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Nitrogênio/química , Fósforo/química , Chuva , Rios/química , Movimentos da Água , China , Fatores de Tempo , Eliminação de Resíduos Líquidos , Qualidade da ÁguaRESUMO
Migratory wild birds can carry various pathogens, such as influenza A virus, which can spread to globally and cause disease outbreaks and epidemics. Continuous epidemiological surveillance of migratory wild birds is of great significance for the early warning, prevention, and control of epidemics. To investigate the pathogen infection status of migratory wild birds in eastern China, fecal samples were collected from wetlands to conduct pathogen surveillance. The results showed that duck orthoreovirus (DRV) and goose parvovirus (GPV) nucleic acid were detected positive in the fecal samples collected from wild ducks, egrets, and swan. Phylogenetic analysis of the amplified viral genes reveals that the isolates were closely related to the prevalent strains in the regions involved in East Asian-Australasian (EAA) migratory flyway. Phylogenetic analysis of the amplified viral genes confirmed that they were closely related to circulating strains in the regions involved in the EAA migration pathway. The findings of this study have expanded the host range of the orthoreovirus and parvovirus, and revealed possible virus transmission between wild migratory birds and poultry.
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Animais Selvagens , Doenças das Aves , Orthoreovirus Aviário , Infecções por Parvoviridae , Parvovirus , Filogenia , Infecções por Reoviridae , Animais , Infecções por Reoviridae/veterinária , Infecções por Reoviridae/epidemiologia , Infecções por Reoviridae/virologia , Orthoreovirus Aviário/isolamento & purificação , Orthoreovirus Aviário/genética , Infecções por Parvoviridae/veterinária , Infecções por Parvoviridae/virologia , Infecções por Parvoviridae/epidemiologia , China/epidemiologia , Doenças das Aves/virologia , Doenças das Aves/epidemiologia , Animais Selvagens/virologia , Parvovirus/genética , Parvovirus/isolamento & purificação , Fezes/virologia , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/virologia , Patos/virologia , Anseriformes/virologia , Monitoramento Epidemiológico/veterináriaRESUMO
COVID-19 can lead to adverse outcomes in patients with pre-existing diseases. Azvudine has been approved for treating COVID-19 in China, but the real-world data is limited. It is aimed to investigate the efficacy of Azvudine in patients with COVID-19 and pre-existing cardiovascular diseases. Patients with confirmed COVID-19 and pre-existing cardiovascular diseases are retrospectively enrolled. The primary outcome is all-cause death during hospitalization. Overall, 351 patients are included, with a median age of 74 years, and 44% are female. 212 (60.6%) patients are severe cases. Azvudine is used in 106 (30.2%) patients and not in 245 (69.8%). 72 patients died during hospitalization. After multivariate adjustment, patients who received Azvudine a lower risk of all-cause death (hazard ratio: 0.431; 95% confidence interval: 0.252-0.738; p = 0.002) than controls. Azvudine therapy is also associated with lower risks of shock and acute kidney injury. For sensitivity analysis in the propensity score-matched cohort (n = 90 for each group), there is also a significant difference in all-cause death between the two groups (hazard ratio: 0.189; 95% confidence interval: 0.071-0.498; p < 0.001). This study indicated that Azvudine therapy is associated with better outcomes in COVID-19 patients with pre-existing cardiovascular diseases.
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Tratamento Farmacológico da COVID-19 , COVID-19 , Doenças Cardiovasculares , Humanos , Feminino , Masculino , Idoso , Doenças Cardiovasculares/tratamento farmacológico , Estudos Retrospectivos , COVID-19/complicações , COVID-19/mortalidade , Pessoa de Meia-Idade , China/epidemiologia , Antivirais/uso terapêutico , SARS-CoV-2/efeitos dos fármacos , Resultado do Tratamento , Idoso de 80 Anos ou mais , Hospitalização/estatística & dados numéricosRESUMO
The analysis of river pollution and assessment of spatial and temporal variation in hydrochemistry are essential to river water pollution control in the context of rapid economic growth and growing pollution threats in China. In this study, we focused on hydrochemical characteristics of the Luanhe River Basin (China) and evaluation of 12 hydrochemical variables obtained from 32 monitoring stations during 2001-2010. In each study year, the streams were monitored in the three hydrological periods (April, August, and October) to observe differences in the impacts of agricultural activity and rainfall pattern. Multivariate statistical methods were applied to the data set, and the river water hydrochemical characteristics were assessed using the water quality identification index (WQIIM). The results showed that parameters had variable contribution to water quality status in different months except for ammonia nitrogen (NH4-N) and total nitrogen (TN), which were the most important parameters in contributing to water quality variations for all three periods. Results of WQIIM revealed that 18 sites were classified as 'meeting standard' while the other 14 sites were classified as 'not meeting standard', with most of the seriously polluted sites located in urban area, mainly due to discharge of wastewater from domestic and industrial sources. Sites with low pollution level were located primarily in smaller tributaries, whereas sites of medium and high pollution levels were in the main river channel and the larger tributaries. Our findings provide valuable information and guidance for water pollution control and water resource management in the Luanhe River Basin.
Assuntos
Rios/química , Estações do Ano , Poluição da Água/análise , Qualidade da Água , China , Abastecimento de ÁguaRESUMO
Solidification/stabilization (S/S) is the prevalent remediation technology for the treatment of heavy metal contaminated soils (HMCS). However, under the stress of complex surrounding environments, S/S effectiveness tends to deteriorate and freezing-thawing is one of the most influential natural forcings. The different proportions of cement, lime, and fly ash were used as the compound curing agents to treat solidified/stabilized HMCS with varying levels of lead contamination. The resulting samples were subjected to up to 180 freeze-thaw cycles (F-T) (1 day per cycle). Unconfined compressive strength (UCS) tests and semi-dynamic leaching tests were performed after F-T to explore the strength evolution of compound solidified/stabilized lead-contaminated soils (Pb-CSCS) and the chemical stability of the lead within. The results show that the F-T duration changes the strength deterioration mechanism of Pb-CSCS under F-T. There has been a shift in the main influencing factor from the promoted curing agent hydration by short-term F-T to the structural damage of the specimen induced by prolonged F-T. The variations in leachate pH, lead leachability, and diffusion ability with progressing F-T revealed a degradation effect of the changes in the physical states of water and crack propagation brought by F-T. These unfavorable changes in soil structure and chemistry reduce the acid resistance of Pb-CSCS. Notably, fly ash and cement facilitate the strength maintenance of Pb-CSCS under long-term F-T conditions. Curing formulations that included both cement and fly ash significantly increased the UCS of treated soils by up to 80.5% (3 F-T) under short-term F-T. In contrast, the curing formulation without fly ash lost 51.8% of its strength after 180 F-T conditions. For lead stabilization, cement and especially lime are favored. The results showed a 25% increase in the total proportion of lime and cement in the curing agent formulation, leading to a 41.4% reduction of lead leaching risk.