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Riparian infiltration zones are crucial for maintaining water quality by reducing the aqueous concentrations of polycyclic aromatic hydrocarbons (PAHs) through adsorption and biodegradation within the aquatic ecosystem. Dissolved organic matter (DOM) are ubiquitous in riparian infiltration zones where they extensively engage in the adsorption and biodegradation of PAHs, thereby influencing PAHs natural attenuation potential within riparian infiltration zones. Few studies have explored the natural attenuation mechanisms of PAHs influenced by DOM in riparian infiltration zones. In this study, the natural attenuation mechanisms of naphthalene (a typical PAHs component), under the influence of DOM, were explored, based on a case riverside source area. Analysis of microbial community structures, and the electron acceptor (e.g., Fe(III), DO/NO3-, SO42-)/electron donor (naphthalene and DOM) concentration changes within the riparian infiltration zone revealed a competitive inhibition relationship between DOM and naphthalene during microbial metabolism. Biodegradation experiments showed that when the concentration of DOM is higher than 4.0 mg·L-1, it inhibits the biodegradation of naphthalene. DOM competitively inhibits the biodegradation of naphthalene through the following mechanisms: (i) triggering microbial antioxidative defense mechanisms, diminishing the available resources for microbial participation in naphthalene degradation; (ii) altering microbial community structure; (iii) modulating microbial EPS composition, reducing the efficiency of microorganisms in utilizing carbon sources; and (iv) inhibiting the expression levels of downstream genes involved in naphthalene degradation. The competitive inhibition constants of DOM with concentrations of 1.0, 2.0, 4.0, 8.0, and 16.0 mg·L-1 on naphthalene biodegradation are -2.0 × 10-3, -5.0 × 10-3,1.0 × 10-3, 4.0 × 10-4, and 1.0 × 10-4, respectively. These findings enhance understanding of PAHs attenuation in riparian infiltration zone, providing a basis for assessing and managing PAHs pollution risks during riparian extraction.
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Background: Men who have sex with men (MSM) face significant risks of Chlamydia trachomatis (CT) and/or Neisseria gonorrhoeae (NG) infection. Nevertheless, only limited studies have looked into the site-specific infection and clearance of CT/NG. In order to prevent transmission, it is essential to understand the underlying factors that drive infection and spontaneous clearance. Methods: A 12-week cohort study examined the association between CT/NG infection, self-clearance, and sexual behaviors among MSM. The Willingness Service recruited participants who completed weekly questionnaires and provided urine, throat, and rectal swab samples. Results: The study involved 151 men, in which 51 (33.8%) were diagnosed with CT/NG infection during the study period. HIV (OR = 11.31), kissing (OR = 1.59), receptive oral sex (OR = 36.64), and insertive anal sex (OR = 19.73) constituted significant risk factors. 100% condom use (OR = 5.78) and antibiotic (OR = 7.53) were more likely to cause spontaneous clearance. Discussion: MSM may engage in riskier sexual behaviors due to insufficient knowledge and awareness of STI prevention, leading to increased susceptibility to NG/CT. It is crucial to concentrate on enhancing health education for MSM. Conclusion: This study found that the rectum was the most prevalent site of CT/NG and sexual behavior can influence the infection. Additionally, the appropriate use of antibiotics and consistent condom use may contribute to clear spontaneously.
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Infecções por Chlamydia , Gonorreia , Homossexualidade Masculina , Comportamento Sexual , Humanos , Masculino , Gonorreia/epidemiologia , Infecções por Chlamydia/epidemiologia , China/epidemiologia , Homossexualidade Masculina/estatística & dados numéricos , Adulto , Estudos Prospectivos , Incidência , Fatores de Risco , Comportamento Sexual/estatística & dados numéricos , Chlamydia trachomatis/isolamento & purificação , Inquéritos e Questionários , Neisseria gonorrhoeae/isolamento & purificação , Adulto Jovem , Pessoa de Meia-IdadeRESUMO
Nitrate attenuation during river bank infiltration is the key process for reducing nitrogen pollution. Temperature is considered to be an important factor affecting nitrate attenuation. However, the magnitude and mechanism of its impact have not been clear for a long time. In this study, the effects of temperature and temperature gradient on the nitrate denitrification rate were investigated via static batch and dynamic soil column simulation experiments. The results showed that temperature had a significant effect on the denitrification rate. Temperature effects were first observed in denitrifying bacteria. At low temperatures, the microorganism diversity was low, resulting in a lower denitrification rate constant. The static experimental results showed that the denitrification rate at 19 °C was approximately 2.4 times that at 10 °C. The dynamic soil column experiment established an exponential positive correlation between the nitrate denitrification decay kinetic constant and temperature. The affinity of denitrifying enzymes for nitrate in the reaction substrate was ordered as follows: decreasing temperature gradient (30 °C â 10 °C) > zero temperature gradient (10 °C) > increasing temperature gradient condition (0 °C â 10 °C). This study provides a theoretical basis for the biogeochemical processes underlying river bank infiltration, which will help aid in the development and utilization of groundwater resources.
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Nitratos , Rios , Nitratos/análise , Temperatura , Desnitrificação , Compostos Orgânicos , Nitrogênio/análise , Solo/químicaRESUMO
The phase transformation from δ- to α-CsPbI3has garnered extensive research interest. However, detailed understanding of this structural transformation at atomistic scale remains elusive. Here, we reported the full atomistic molecular dynamics simulation of this important phase transformation using an enhanced sampling method, Metadynamics (MetaD). Particularly, two-stage of dynamic transformation related to [PbI3]- chains' motions was observed, namely, the intrachain rearrangement followed by interchain connection. Moreover, the dynamic motion of Cs+ cations plays an important role in facilitating the interchain connection kinetically. The insights reported in this work will provide valuable guidance for further advancing the understanding of phase transformation of CsPbI3.
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Secondary distribution of HIV self-testing (HIVST) among individual social networks was an effective approach to expanding HIV testing among men who have sex with men (MSM). However, understanding the factors associated with first-time HIV testing behaviors in the secondary distribution of HIVST programs is limited. Hence, this study aims to identify factors related to first-time testers in the secondary distribution of HIVST. Participants were recruited from five provinces in southern China through Blued, a geo-social gay networking app in China from January 2021 to December 2021. Eligible consented participants (referred to as "seeds") finished a baseline survey and then applied for up to five HIVST kits. They were encouraged to distribute HIVST kits to other MSM (referred to as "alters") and alters were encouraged to scan a QR code to return their photographed testing results. All alters were invited to finish an online survey. In total, 229 seeds reached 292 alters, among whom 126 (43.2%) were first-time testers whereas 166 (56.8%) were non-first-time testers. Importantly, our results demonstrated that the first-time HIV testers were more likely to self-report as heterosexual (aOR = 4.88, 95% CI 1.01-23.61), disclose sexual orientation and/or SSB (aOR = 1.73, 95% CI 1.01-2.96), and receive HIVST knowledge from the seeds (aOR = 3.25, 95% CI 1.02-10.34). However, those who had sex with male partners in the last three months were less likely to be first-time testers (aOR = 0.43, 95% CI 0.23-0.82). Practical implications and limitations were also discussed to improve future HIV prevention programs.
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Infecções por HIV , Minorias Sexuais e de Gênero , Feminino , Masculino , Humanos , Homossexualidade Masculina , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Amigos , Teste de HIV , China/epidemiologiaRESUMO
Chemically inert organic networks exhibiting electrical conductivity comparable to metals can advance organic electronics, catalysis, and energy storage systems. Covalent-organic frameworks (COFs) have emerged as promising materials for those applications due to their high crystallinity, porosity, and tunable functionality. However, their low conductivity has limited their practical utilization. In this study, copper-coordinated-fluorinated-phthalocyanine and 2,3,6,7-tetrahydroxy-9,10-anthraquinone-based COF (CuPc-AQ-COF) films with ultrahigh conductivity are developed. The COF films exhibit an electrical conductivity of 1.53 × 103 S m-1 and a Hall mobility of 6.02 × 102 cm2 V-1 s-1 at 298 K, reaching the level of metals. The films are constructed by linking phthalocyanines and anthraquinones through vapor-assisted synthesis. The high conductivity properties of the films are attributed to the molecular design of the CuPc-AQ-COFs and the generation of high-quality crystals via the vapor-assisted method. Density functional theory analysis reveals that an efficient donor-acceptor system between the copper-coordinated phthalocyanines and anthraquinones significantly promotes charge transfer. Overall, the CuPc-AQ-COF films set new records of COF conductivity and mobility and represent a significant step forward in the development of COFs for electronic, catalytic, and electrochemical applications.
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Monitoring genetic diversity and recent HIV infections (RHIs) is critical for understanding HIV epidemiology. Here, we report HIV-1 genetic diversity and RHIs in blood samples from 190 HIV-positive MMSCs in Zhuhai, China. MMSCs with newly reported HIV were enrolled from January 2020 to June 2022. A nested PCR was performed to amplify the HIV polymerase gene fragments at HXB2 positions 2604-3606. We constructed genetic transmission network at both 0.5% and 1.5% distance thresholds using the Tamura-Nei93 model. RHIs were identified using a recent infection testing algorithm (RITA) combining limiting antigen avidity enzyme immunoassay (LAg-EIA) assay with clinical data. The results revealed that 19.5% (37/190) were RHIs and 48.4% (92/190) were CRF07_BC. Two clusters were identified at a 0.5% distance threshold. Among them, one was infected with CRF07_BC for the long term, and the other was infected with CRF55_01B recently. We identified a total of 15 clusters at a 1.5% distance threshold. Among them, nine were infected with CRF07_BC subtype, and RHIs were found in 38.8% (19/49) distributed in eight genetic clusters. We identified a large active transmission cluster (n = 10) infected with a genetic variant, CRF79_0107. The multivariable logistic regression model showed that clusters were more likely to be RHIs (adjusted OR: 3.64, 95% CI: 1.51~9.01). The RHI algorithm can help to identify recent or ongoing transmission clusters where the prevention tools are mostly needed. Prompt public health measures are needed to contain the further spread of active transmission clusters.
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Infecções por HIV , Soropositividade para HIV , HIV-1 , Masculino , Humanos , Infecções por HIV/epidemiologia , HIV-1/genética , China/epidemiologia , Variação GenéticaRESUMO
Artificial groundwater recharge is a relatively economic and efficient method for solving shortages and uneven spatial-temporal distribution of water resources. Changes in groundwater quality during the recharge process are a key issue that must be addressed. Identifying the hydrogeochemical reactions that occur during recharge can be vital in predicting trends in groundwater quality. However, there are few studies on the evolution of groundwater quality during artificial recharge that comprehensively consider environmental, chemical, organic matter, and microbiological indicators. Based on an artificial groundwater recharge experiment in Xiong'an New Area, this study investigated the hydrogeochemical changes during groundwater recharge through a well. The results indicate that (1) as large amounts of recharge water (RW) were injected, the groundwater level initially rose rapidly, then fluctuated slowly, and finally rose again. (2) Water quality indicators, dissolved organic matter (DOM), and microbial communities were influenced by the mixture of RW and the background groundwater before recharge (BGBR), as well as by water-rock interactions, such as mineral dissolution-precipitation and redox reactions. (3) During well recharge, aerobic respiration, nitrification, denitrification, high-valence manganese (Mn) and iron (Fe) minerals reduction dissolution, and Mn2+ and Fe2+ oxidation-precipitation occurred sequentially. (4) DOM analysis showed that protein-like substances in the BGBR were the main carbon sources for aerobic respiration and denitrification, while humic-like substances carried by the RW significantly enhanced Mn and Fe minerals reduction dissolution. Therefore, RW quality significantly affects groundwater quality after artificial groundwater well recharge. Controlling indicators, such as dissolved oxygen (DO) and DOM, in the RW can effectively reduce harm to groundwater quality after recharge. This study is of theoretical and practical significance for in-depth analysis of the evolution of groundwater quality during artificial well recharge, prediction of trends in groundwater quality during and after recharge and ensuring groundwater quality safety.
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Background/purpose: Alveolar bone fenestration and dehiscence is common in untreated patients and potentially harmful. This study was to evaluate the effect of augmented corticotomy (AC) on the prevention and treatment of alveolar bone defects in skeletal class III high-angle patients during presurgical orthodontic treatment (POT). Materials and methods: Fifty patients with skeletal Class III high-angle malocclusion were enrolled, of whom 25 patients (G1) underwent traditional POT and 25 patients (G2) received AC during POT. The alveolar bone fenestration and dehiscence around the upper and lower anterior teeth were measured by CBCT. The incidence and transition of fenestration and dehiscence in the two groups were compared by the chisquare and MannâWhitney rank-sum tests. Results: Before treatment (T0), the incidence of fenestration and dehiscence around the anterior teeth of all patients was 39.24% and 24.10%, respectively. After POT (T1), the incidence of fenestration in G1 and G2 was 49.83% and 25.86%, respectively, and the incidence of dehiscence in G1 and G2 was 58.08% and 32.07%, respectively. For teeth without fenestration and dehiscence at T0, more anterior teeth in G1 exhibited fenestration and dehiscence at T1 than in G2. For teeth with fenestration and dehiscence at T0, most transitions in G1 were maintained or worsened, but "cure" cases were observed in G2. After POT, the cure rates of fenestration and dehiscence in G2 were 80.95% and 91.07%, respectively. Conclusion: During the POT of skeletal Class III high-angle patients, augmented corticotomy can significantly treat and prevent alveolar bone fenestration and dehiscence around anterior teeth.
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The axon initial segment (AIS) is a highly specialized neuronal compartment that regulates the generation of action potentials and maintenance of neuronal polarity. Live imaging of the AIS is challenging due to the limited number of suitable labeling methods. To overcome this limitation, we established a novel approach for live labeling of the AIS using unnatural amino acids (UAAs) and click chemistry. The small size of UAAs and the possibility of introducing them virtually anywhere into target proteins make this method particularly suitable for labeling of complex and spatially restricted proteins. Using this approach, we labeled two large AIS components, the 186â kDa isoform of neurofascin (NF186; encoded by Nfasc) and the 260â kDa voltage-gated Na+ channel (NaV1.6, encoded by Scn8a) in primary neurons and performed conventional and super-resolution microscopy. We also studied the localization of epilepsy-causing NaV1.6 variants with a loss-of-function effect. Finally, to improve the efficiency of UAA incorporation, we developed adeno-associated viral (AAV) vectors for click labeling in neurons, an achievement that could be transferred to more complex systems such as organotypic slice cultures, organoids, and animal models.
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Segmento Inicial do Axônio , Química Click , Animais , Potenciais de Ação/fisiologia , Aminoácidos/metabolismo , Segmento Inicial do Axônio/metabolismo , Neurônios , Camundongos , RatosRESUMO
HIV self-testing (HIVST) is an effective method to expand HIV testing coverage worldwide. We analyze the results of HIVST and sexual behaviors of first-time testers among Men who have sex with men (MSM) who participated in a secondary distribution of HIVST kits. A total of 589 participants were recruited, including 173 first-time testers and 416 non-first-time testers. The first-time testers were mainly of Han ethnicity (aOR 1.88, 95% CI 1.10, 3.24), more likely to be HIV positive (aOR 7.18, 95% CI 2.37, 21.72), and had higher income (aOR 2.01, 95% CI 1.10, 3.69). Both groups were less likely to have anal sex with male partners (χ2: 146.24, P < 0.01), (χ2: 582.72, P < 0.01) or have sex with female partners (χ2: 19.01, P < 0.01), (χ2: 35.74, P < 0.01) after HIVST. We should expand HIVST among MSM and other key populations to identify first-time testers.
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Infecções por HIV , Minorias Sexuais e de Gênero , Masculino , Humanos , Feminino , Homossexualidade Masculina , Autoteste , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Inquéritos e Questionários , Teste de HIV , China/epidemiologiaRESUMO
Ammonium (NH4+) enrichment of riverbank filtration (RBF) systems is gaining popularity. However, most previous research has concentrated on NO3- removal efficiencies, while the mechanisms of NH4+ enrichment remain unknown. A nitrogen biogeochemical process model was developed for the quantitative analysis of NH4+ enrichment in the Kaladian well field in northwest Songyuan City, NE China. Data from laboratory experiments and in-situ monitoring were used to determine initial values and calibrate the thermodynamic/kinetic parameters representing nitrogen (N) biogeochemical reactions. (1) The NO3- from river was subjected to denitrification (DNF) and dissimilatory nitrate reduction to ammonium (DNRA) within 10-14 m of the shore, whereas the NH4+ in groundwater was caused by DNRA, organic nitrogen mineralization (MIN), and mixing with laterally recharged high NH4+ groundwater. (2) DNF and DNRA were regulated by hydrodynamic processes, with the ranges of these processes being more significant in the wet season due to a higher hydraulic gradient. MIN occurred widely throughout the water flow path, with temperature primarily controlling the rates of the three reactions. (3) DNRA activity was relatively higher in the wet season when the water temperature was higher within 10-14 m of the shore. In the wet season, DNRA contributed 25%-30% to NO3- reduction, which was higher than in the dry season (5%-10%). DNRA contributed at least 40% and 15% to NH4+ enrichment in the wet and dry seasons, respectively. (4). Organic N in media gradually released NH4+ into groundwater via MIN and desorption across the entire flow path, with contributions to NH4+ enrichment reaching 75% and 85%, respectively, in the wet and dry seasons.
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Compostos de Amônio , Nitrogênio , Desnitrificação , Nitratos/análise , Óxidos de Nitrogênio , Compostos Orgânicos , ÁguaRESUMO
BACKGROUND AND PURPOSE: Variants in SCN8A, the NaV 1.6 channel's coding gene, are characterized by a variety of symptoms, including intractable epileptic seizures, psychomotor delay, progressive cognitive decline, autistic features, ataxia or dystonia. Standard anticonvulsant treatment has a limited impact on the course of disease. EXPERIMENTAL APPROACH: We investigated the therapeutic potential of eslicarbazepine (S-licarbazepine; S-lic), an enhancer of slow inactivation of voltage gated sodium channels, on two variants with biophysical and neuronal gain-of-function (G1475R and M1760I) and one variant with biophysical gain-of-function but neuronal loss-of-function (A1622D) in neuroblastoma cells and in murine primary hippocampal neuron cultures. These three variants cover the broad spectrum of NaV 1.6-associated disease and are linked to representative phenotypes of mild to moderate epilepsy (G1475R), developmental and epileptic encephalopathy (M1760I) and intellectual disability without epilepsy (A1622D). KEY RESULTS: Similar to known effects on NaV 1.6 wildtype channels, S-lic predominantly enhances slow inactivation on all tested variants, irrespective of their particular biophysical mechanisms. Beyond that, S-lic exhibits variant-specific effects including a partial reversal of pathologically slowed fast inactivation dynamics (A1622D and M1760I) and a trend to reduce enhanced persistent Na+ current by A1622D variant channels. Furthermore, our data in primary transfected neurons reveal that not only variant-associated hyperexcitability (M1760I and G1475R) but also hypoexcitability (A1622D) can be modulated by S-lic. CONCLUSIONS AND IMPLICATIONS: S-lic has not only substance-specific effects but also variant-specific effects. Personalized treatment regimens optimized to achieve such variant-specific pharmacological modulation may help to reduce adverse side effects and improve the overall therapeutic outcome of SCN8A-related disease.
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Dibenzazepinas , Epilepsia , Camundongos , Animais , Mutação , Epilepsia/tratamento farmacológico , Epilepsia/genética , Dibenzazepinas/uso terapêutico , Canal de Sódio Disparado por Voltagem NAV1.6/genéticaRESUMO
BACKGROUND: Variants in SCN8A are associated with a spectrum of epilepsies and neurodevelopmental disorders. Ataxia as a predominant symptom of SCN8A variation has not been well studied. We set out to investigate disease mechanisms and genotype-phenotype correlations of SCN8A-related ataxia. METHODS: We collected genetic and electro-clinical data of ten individuals from nine unrelated families carrying novel SCN8A variants associated with chronic progressive or episodic ataxia. Electrophysiological characterizations of these variants were performed in ND7/23 cells and cultured neurons. FINDINGS: Variants associated with chronic progressive ataxia either decreased Na+ current densities and shifted activation curves towards more depolarized potentials (p.Asn995Asp, p.Lys1498Glu and p.Trp1266Cys) or resulted in a premature stop codon (p.Trp937Ter). Three variants (p.Arg847Gln and biallelic p.Arg191Trp/p.Asp1525Tyr) were associated with episodic ataxia causing loss-of-function by decreasing Na+ current densities or a hyperpolarizing shift of the inactivation curve. Two additional episodic ataxia-associated variants caused mixed gain- and loss-of function effects in ND7/23 cells and were further examined in primary murine hippocampal neuronal cultures. Neuronal firing in excitatory neurons was increased by p.Arg1629His, but decreased by p.Glu1201Lys. Neuronal firing in inhibitory neurons was decreased for both variants. No functional effect was observed for p.Arg1913Trp. In four individuals, treatment with sodium channel blockers exacerbated symptoms. INTERPRETATION: We identified episodic or chronic ataxia as predominant phenotypes caused by variants in SCN8A. Genotype-phenotype correlations revealed a more pronounced loss-of-function effect for variants causing chronic ataxia. Sodium channel blockers should be avoided under these conditions. FUNDING: BMBF, DFG, the Italian Ministry of Health, University of Tuebingen.
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Ataxia , Neurônios , Humanos , Animais , Camundongos , Ataxia/diagnóstico , Ataxia/genética , Códon sem Sentido , Bloqueadores dos Canais de Sódio , Canal de Sódio Disparado por Voltagem NAV1.6/genéticaRESUMO
Background: To assess whether HIV self-testing (HIVST) has a better performance in identifying HIV-infected cases than the facility-based HIV testing (HIVFBT) approach. Methods: A cross-sectional study was conducted among men who have sex with men (MSM) by using an online questionnaire (including information on sociodemographic, sexual biography, and HIV testing history) and blood samples (for limiting antigen avidity enzyme immunoassay, gene subtype testing, and taking confirmed HIV test). MSM who were firstly identified as HIV positive through HIVST and HIVFBT were compared. Chi-square or Fisher's exact test was used to explore any association between both groups and their subgroups. Results: In total, 124 MSM HIV cases were identified from 2017 to 2021 in Zhuhai, China, including 60 identified through HIVST and 64 through HIVFBT. Participants in the HIVST group were younger (≤30 years, 76.7% vs. 46.9%), were better educated (>high school, 61.7% vs. 39.1%), and had higher viral load (≥1,000 copies/ml, 71.7% vs. 50.0%) than MSM cases identified through HIVFBT. The proportion of early HIV infection in the HIVST group was higher than in the HIVFBT group, identified using four recent infection testing algorithms (RITAs) (RITA 1, 46.7% vs. 25.0%; RITA 2, 43.3% vs. 20.3%; RITA 3, 30.0% vs. 14.1%; RITA 4, 26.7% vs. 10.9%; all p < 0.05). Conclusions: The study showed that HIVST has better HIV early detection among MSM and that recent HIV infection cases mainly occur in younger and better-educated MSM. Compared with HIVFBT, HIVST is more accessible to the most at-risk population on time and tends to identify the case early. Further implementation studies are needed to fill the knowledge gap on this medical service model among MSM and other target populations.
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Infecções por HIV , Minorias Sexuais e de Gênero , Estudos Transversais , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Teste de HIV , Homossexualidade Masculina , Humanos , Masculino , Autocuidado , AutotesteRESUMO
Riverbank filtration (RBF) is a well-established technique worldwide, and is critical for the maintenance of groundwater quality and production of clean drinking water. Evaluation of the decay of exogenous nitrate (NO3-) in river water and the enrichment of ammonium (NH4+) in groundwater during RBF is important; these two processes are mainly influenced by denitrification (DNF) and dissimilatory nitrate reduction to ammonium (DNRA) controlled by the groundwater carbon load. In this study, the effects of carbon load (organic carbon [OC]: NO3-) on the competing nitrate reduction (DNRA and DNF) were assessed during RBF using field monitoring and a laboratory batch experiment. Results show the groundwater OC: NO3- ratio did not directly affect the reaction rate of DNRA and DNF, however, it could control the competitive partitioning between the two. In the near-shore zone, the groundwater OC: NO3- ratio shows significant seasonal variations along the filtration path owing to the changing conditions of redox, OC-rich, and NO3--limited. A greater proportion of NO3- would be available for DNRA in the wet season with higher OC: NO3- ratio (> 10), resulting in a significantly NH4+-N enrichment rate (from 1.43 × 10-3 to 9.54 × 10-4 mmol L-1 d-1) in the near-shore zone where the zone of Mn (IV) oxide reduction. However, the activity of DNRA was suppressed with lower OC: NO3- ratio (< 10) in the dry season, resulting in a stable NH4+-N enrichment rate (from 3.12 × 10-4 to 1.30 × 10-4 mmol L-1 d-1). Benefiting from seasonal variation of OC-rich and NO3--limited conditions, DNRA bacteria outcompeted denitrifiers, which eventually led to seasonal differences in NO3- reduction in the near-shore zone. Overall, under the effect of DNRA induced by continuous high carbon load in RBF systems, nitrogen input is not permanently removed but rather retained in groundwater during RBF.
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Compostos de Amônio , Nitratos , Carbono , Desnitrificação , Nitrogênio , Óxidos de Nitrogênio , Compostos Orgânicos , OxirreduçãoRESUMO
Groundwater (GW) and surface water (SW) are important components of water resources and play key roles in social and economic development and regional ecological security. There are currently several stresses placing immense pressure on the GW resources of the Baiyangdian Lake Basin (BLB) in China, including climate change. A series of ecological and environmental challenges have manifested in the plain area of the BLB due to long-term over-exploitation of GW, including regional declines in GW level, aquifer drainage, land subsidence, and soil secondary salinization. Climate change may aggravate environmental challenges by altering GW recharge rates and availability of GW. This study applied the fully processed and physically-based numerical models, MODFLOW and the Soil & Water Assessment Tool (SWAT) in a semi-coupled modeling framework. The aim of the study was to quantitatively analyze changes to shallow GW levels and reserves in the plain area of BLB over the next 15 years (2021-2035) under climate change and different artificial recharge schemes. The results indicated that GW storage and levels are rising under the different GW recharge schemes. The maximum variation in the GW level was 20-30 m under a rainfall assurance rate of 50% and water level in the depression cone increased 14.20-14.98 m. This study can act as a theoretical basis for the development of a more sustainable GW management scheme in the plain area of the BLB and for the management and protection of aquifers in other areas with serious GW overdraft.
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Mudança Climática , Água Subterrânea , Monitoramento Ambiental/métodos , Lagos , Solo , ÁguaRESUMO
Objectives: It is unclear if a high level of alcohol consumption is a risk factor for liver fibrosis for people living with HIV (PLWH). This study systematically summarizes the risk relationship between different alcohol consumption and the incidence of liver fibrosis among PLWH. Methods: We identified potential studies by searching the PubMed, Embase, Web of Science Library, and CNKI databases up to September 26th, 2021. Observation studies in PLWH that evaluated the relationship between alcohol consumption and the risk of liver fibrosis and estimated the effect of alcohol with pooled odds ratios (pooled ORs) and 95% confidence intervals (CIs) were included. Results: There were total 15 studies included in data analysis. Three studies were set up as cohort studies and the other twelve were cross-sectional studies. Our study was based on 22,676 individuals and 2,729 liver fibrosis cases from 15 studies. Alcohol abuse is a significant risk factor of liver fibrosis (pooled OR = 2.25, 95% CI: 1.59-3.17, p < 0.05) among PLWH. Daily alcohol consumption > 50 g can elevate the risk of liver fibrosis (pooled OR = 3.10, 95% CI: 2.02-4.73, p < 0.05) among PLWH. However, high-risk alcohol consumption determined by AUDIT-C (AUDIT-C ≥ 4) had little or no effect on subsequent liver fibrosis risk. Further, alcohol consumption > 50 g is also a risk factor to liver fibrosis in PLWH co-infected with HCV (pooled OR = 2.48, 95% CI: 1.62-3.80, p < 0.05) and in HIV mono-infected (pooled OR = 1.85, 95% CI: 1.00-3.43, p < 0.05). Conclusion: Alcohol consumption is associated with an increased risk of liver fibrosis in PLWH. HCV co-infection with alcohol abuse could possibly induce a higher risk of liver fibrosis than HIV mono-infected patients. Systematic Review Registration: PROSPERO, identifier (CRD42021272604).
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Alcoolismo , Infecções por HIV , Hepatite C , Consumo de Bebidas Alcoólicas/efeitos adversos , Alcoolismo/complicações , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Hepatite C/complicações , Hepatite C/epidemiologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/etiologiaRESUMO
Western Jilin Province is one of the world's three major saline-alkali land distribution areas, and is also an important area of global climate change and carbon cycle research. Rhizosphere soil microorganisms and enzymes are the most active components in soil, which are closely related to soil carbon cycle and can reflect soil organic carbon (SOC) dynamics sensitively. Soil inorganic carbon (SIC) is the main existing form of soil carbon pool in arid saline-alkali land, and its quantity distribution affects the pattern of soil carbon accumulation and storage. Previous studies mostly focus on SOC, and pay little attention to SIC. Illumina Miseq high-throughput sequencing technology was used to reveal the changes of community structure in three maize fields (M1, M2 and M3) and three rice fields (R1, R2 and R3), which were affected by different levels of salinization during soil development. It is a new research topic of soil carbon cycle in saline-alkali soil region to investigate the effects of soil microorganisms and soil enzymes on the transformation of SOC and SIC in the rhizosphere. The results showed that the root-soil-microorganism interaction was changed by saline-alkali stress. The activities of catalase, invertase, amylase and ß-glucosidase decreased with increasing salinity. At the phylum level, most bacterial abundance decreases with increasing salinity. However, the relative abundance of Proteobacteria and Firmicutes in maize field and Firmicutes, Proteobacteria and Nitrospirae in rice field increased sharply under saline-alkali stress. The results of redundancy analysis showed that the differences of rhizosphere soil between the three maize and three rice fields were mainly affected by ESP, pH and soil salt content. In saline-alkali soil region, ß-glucosidase activity and amylase were significantly positively correlated with SOC content in maize fields, while catalase and ß-glucosidase were significantly positively correlated with SOC content in rice fields. Actinobacteria, Bacteroidetes and Verrucomicrobia had significant positive effects on SOC content of maize and rice fields. Proteobacteria, Gemmatimonadetes and Nitrospirae were positively correlated with SIC content. These enzymes and microorganisms are beneficial to soil carbon sequestration in saline-alkali soils.
Assuntos
Álcalis/análise , Carbono/análise , Bactérias Gram-Negativas/enzimologia , Bactérias Gram-Negativas/genética , Bactérias Gram-Positivas/enzimologia , Bactérias Gram-Positivas/genética , Rizosfera , Salinidade , Microbiologia do Solo , Solo/química , Produtos Agrícolas/enzimologia , Produtos Agrícolas/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Concentração de Íons de Hidrogênio , Oryza/enzimologia , Oryza/microbiologia , Zea mays/enzimologia , Zea mays/microbiologiaRESUMO
Background: Solidarity, such as community connectedness and social cohesion, may be useful in improving HIV testing uptake among men who have sex with men (MSM). This study aimed to evaluate the impact of solidarity on HIV testing before the coronavirus disease 2019 (COVID-19) and HIV testing willingness during COVID-19 among MSM in China. Materials and Methods: An online survey was conducted to collect sociodemographic, sexual behavioral, and solidarity items' information from the participants. We first used factor analysis to reveal the principal component of the solidarity items and then used logistic regression to study the impact of solidarity on HIV testing, by adjusting the possible confounding factors, such as age and education. Results: Social cohesion and community connectedness were revealed by the factor analysis. MSM with high community connectedness were more willing to undergo HIV testing before the epidemic adjusted by age [odds ratio (OR): 1.07, 95% CI: 1.01-1.13]. The community connectedness was also related to the willingness of HIV testing during the epidemic, with adjustments of 1.09 (95% CI: 1.03-1.15). People who did not test for HIV before the COVID-19 epidemic were more willing to have the HIV test during the epidemic, which was correlated with the community connectedness, and the OR value was 1.14 (95%: 1.03-1.25). Conclusion: A high level of community connectedness helped to increase the HIV testing rate before COVID-19 and the willingness of HIV testing during the epidemic among MSM. Strategies can strengthen the role of the community in the management and service of MSM.