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The utilization of anionic redox chemistry provides an opportunity to further improve the energy density of Li-ion batteries, particularly for Li-rich layered oxides. However, oxygen-based hosts still suffer from unfavorable structural rearrangement, including the oxygen release and transition metal (TM)-ion migration, in association with the tenuous framework rooted in the ionicity of the TM-O bonding. An intrinsic solution, by using a sulfur-based host with strong TM-S covalency, is proposed here to buffer the lattice distortion upon the highly activating sulfur redox process, and it achieves howling success in stabilizing the host frameworks. Experimental results demonstrate the prolonged preservation of the layered sulfur lattice, especially the honeycomb superlattice, during the Li+ extraction/insertion process in contrast to the large structural degeneration in Li-rich oxides. Moreover, the Li-rich sulfide cathodes exhibited a negligible overpotential of 0.08 V and a voltage drop of 0.13 mV/cycle, while maintaining a substantial reversible capacity upon cycling. These superior electrochemical performances can be unambiguously ascribed to the much shorter trajectories of sulfur in comparison to those of oxygen revealed by molecular dynamics simulations at a large scale (â¼30 nm) and a long time scale (â¼300 ps) via high-dimensional neural network potentials during the delithiation process. Our findings highlight the importance of stabilizing host frameworks and establish general guidance for designing Li-rich cathodes with durable anionic redox chemistry.
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BACKGROUND: Anthocyanins are the most important compounds for nutritional quality and economic values of blood orange. However, there are few reports on the pre-harvest treatment accelerating the accumulation of anthocyanins in postharvest blood orange fruit. Here, we performed a comparative transcriptome and metabolomics analysis to elucidate the underlying mechanism involved in seasonal drought (SD) treatment during the fruit expansion stage on anthocyanin accumulation in postharvest 'Tarocco' blood orange fruit. RESULTS: Our results showed that SD treatment slowed down the fruit enlargement and increased the sugar accumulation during the fruit development and maturation period. Obviously, under SD treatment, the accumulation of anthocyanin in blood orange fruit during postharvest storage was significantly accelerated and markedly higher than that in CK. Meanwhile, the total flavonoids and phenols content and antioxidant activity in SD treatment fruits were also sensibly increased during postharvest storage. Based on metabolome analysis, we found that substrates required for anthocyanin biosynthesis, such as amino acids and their derivatives, and phenolic acids, had significantly accumulated and were higher in SD treated mature fruits compared with that of CK. Furthermore, according to the results of the transcriptome data and weighted gene coexpression correlation network analysis (WGCNA) analysis, phenylalanine ammonia-lyase (PAL3) was considered a key structural gene. The qRT-PCR analysis verified that the PAL3 was highly expressed in SD treated postharvest stored fruits, and was significantly positively correlated with the anthocyanin content. Moreover, we found that other structural genes in the anthocyanin biosynthesis pathway were also upregulated under SD treatment, as evidenced by transcriptome data and qRT-PCR analysis. CONCLUSIONS: The findings suggest that SD treatment promotes the accumulation of substrates necessary for anthocyanin biosynthesis during the fruit ripening process, and activates the expression of anthocyanin biosynthesis pathway genes during the postharvest storage period. This is especially true for PAL3, which co-contributed to the rapid accumulation of anthocyanin. The present study provides a theoretical basis for the postharvest quality control and water-saving utilization of blood orange fruit.
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Antocianinas , Frutas , Frutas/metabolismo , Secas , Antioxidantes/metabolismo , Perfilação da Expressão GênicaRESUMO
OBJECTIVE: This study aimed to systematically analyze the efficacy and toxicity of lurbinectedin as a second-line or subsequent treatment for extensive-stage small cell lung cancer (ES-SCLC). METHODS: Candidate studies were identified in PubMed, Embase, Cochrane Library, ClinicalTrials.gov, CNKI, and Wanfang databases up to 1 May 2024. Objective remission rate (ORR), disease control rate (DCR), duration of response (DOR), progression-free survival (PFS), overall survival (OS), and adverse events (AEs) were extracted, respectively. The efficacy and toxicity of lurbinectedin in ES-SCLC were analyzed by meta-analysis. RESULTS: Six eligible prospective studies were included in this meta-analysis, including 536 patients with ES-SCLC who received second-line or subsequent treatment. In pooled analysis, the ORR of lurbinectedin was 35% (95% confidence interval [CI] 29-41), DCR was 67% (95%CI 58-76), DOR was 5.33 months (95%CI 4.51-6.16), PFS was 3.38 months (95%CI 2.59-4.17), and OS was 7.49 months (95%CI 5.11-9.87). The incidence of AEs and severe adverse events (SAEs) was 92% (95%CI 78-100) and 37% (95%CI 19-57), respectively. The most common AEs were leukopenia, neutropenia, anemia, and thrombocytopenia, with incidences of 81% (68-91), 74% (57-88), 73% (35-98) and 57% (46-68), respectively. CONCLUSION: As a promising alternative for second-line treatment for ES-SCLC, lurbinectedin has a certain level of efficacy and a favorable safety profile. The integration of lurbinectedin with other therapeutic modalities presents an emerging area warranting further investigation.
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Carbolinas , Compostos Heterocíclicos de 4 ou mais Anéis , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , Carbolinas/efeitos adversos , Carbolinas/uso terapêutico , Carbolinas/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/mortalidade , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/patologia , Carcinoma de Pequenas Células do Pulmão/mortalidade , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Compostos Heterocíclicos de 4 ou mais Anéis/efeitos adversos , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Antineoplásicos/uso terapêutico , Antineoplásicos/efeitos adversos , Resultado do Tratamento , Intervalo Livre de Progressão , Estadiamento de NeoplasiasRESUMO
To identify the phenotypic and genomic characteristics of K. pneumoniae KP43 from bloodstream infection. KP43 was resistant to ticarcillin and tetracycline and was hypervirulent in the Galleria mellonella larvae infection model, positive for string test, and possessed high-level macrophage killing resistance. The hypervirulence phenotype was associated with the chromosome integration of ICEKp1 carrying iroBCDN-iroP, rmpADC, and peg-344, and a novel plasmid pKP43_vir_amr harboring iutAiucABCD. pKP43_vir_amr was an IncFIBκ/FII virulence-resistance hybrid conjugative plasmid which also carried antibiotic resistance genes. The emergence of such a strain and the spread of the novel virulence-resistance plasmid might pose a potential threat to public health.
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Infecções por Klebsiella , Klebsiella pneumoniae , Animais , Humanos , Virulência/genética , Klebsiella pneumoniae/genética , Infecções por Klebsiella/microbiologia , Plasmídeos/genética , Antibacterianos/farmacologia , Cromossomos , beta-Lactamases/genéticaRESUMO
BACKGROUND: Older migrant workers (OMWs) in China face unique challenges rooted in their early life experiences, which increase their vulnerability to psychological and behavioral problems in adulthood. By utilizing the cumulative disadvantage model and the social-ecological systems theory, this study explored the effect of childhood family adversity on adulthood depression in the mediating roles of OMWs' social-ecological microsystem and mesosystem and further examined gender differences in these associations. METHODS: Data were collected from the China Health and Retirement Longitudinal Study (CHARLS), involving a sample of 4,309 OMWs aged 50 and above. The measures included the Center for Epidemiological Research Depression Scale, childhood family adversity, socioeconomic status, marital quality, and physical and cognitive health. RESULTS: Childhood family adversity was positively associated with adulthood depression among OMWs. Social microsystem (physical and cognitive health) and mesosystem (marital quality and socioeconomic status) factors significantly mediated this relationship. Multi-group analysis revealed that the mediating effects of marital quality and socioeconomic status were stronger for female OMWs, while the mediating effects of physical and cognitive health were stronger for male OMWs. CONCLUSIONS: The findings suggest that childhood family adversity has a lasting impact on the mental health of OMWs, and that social-ecological systems factors play an important role in this relationship. The study also highlights the need for gender-specific interventions to address the mental health needs of OMWs.
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Depressão , Migrantes , Humanos , Masculino , Feminino , China/epidemiologia , Migrantes/psicologia , Migrantes/estatística & dados numéricos , Pessoa de Meia-Idade , Depressão/epidemiologia , Depressão/psicologia , Estudos Longitudinais , Fatores Sexuais , Idoso , Experiências Adversas da Infância/estatística & dados numéricos , Experiências Adversas da Infância/psicologia , Meio Social , População do Leste AsiáticoRESUMO
Radiotherapy, a common cancer treatment, leads to infertility in male cancer survivors, particularly young and middle-aged patients. Nicotinamide mononucleotide (NMN), a precursor of nicotinamide adenine dinucleotide (NAD +), plays crucial roles in energy metabolism, DNA repair, and gene expression. The purpose of this study is to investigate the protective effects and underlying mechanisms of NMN against ionizing radiation (IR)-induced testicular injury and spermatogenic dysfunction in an adult male mouse model. To assess the effects of NMN, single whole-body γ-ray irradiation is used to induce testicular injury and spermatogenic dysfunction in adult male mice. NMN is orally administered at 500â mg/kg before and after IR exposure. The structural and cellular damage to the testes caused by 5 Gy γ-ray irradiation, as well as the protective effect of NMN on testicular spermatogenic dysfunction, are evaluated. The serum hormone testosterone, LH, and FSH levels, as well as testicular NAD +, lactate, and pyruvate levels, are detected. Furthermore, the expressions of the apoptosis-related genes Bcl-2, Bax, and Caspase-3 and the rate-limiting enzymes HK2, PKM2, and LDHA, which are potentially associated with the mechanism of injury, are examined. The results demonstrate that 5â Gy γ-ray irradiation exposure causes a decrease in the serum testosterone, LH, and FSH levels in adult male mice, as well as in the testicular NAD +, lactate, and pyruvate levels, and causes damage to the testicular structure and cells. Morphometric analysis reveal a decrease in the testis mass, seminiferous tubule diameter, and height of the germinal epithelium. The sperm quantity, motility, and testicular volume are reduced in the 5â Gy group but are restored by NMN supplementation. NMN intervention downregulates the expressions of proapoptotic genes ( Bax and Caspase-3) and upregulates the expression of an antiapoptotic gene ( Bcl- 2). Sertoli cells marker genes ( WT-1, GATA-4, SOX9, and vimentin) and glycolysis rate-limiting enzyme-encoding genes ( HK2, PKM2, LDHA) are significantly upregulated. In summary, NMN has a positive regulatory effect on testicular spermatogenic dysfunction in male mice induced by ionizing radiation. This positive effect is likely achieved by promoting the proliferation of spermatogenic cells and activating glycolytic pathways. These findings suggest that NMN supplementation may be a potential protective strategy to prevent reproductive damage to male subjects from ionizing radiation.
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Under-deposit corrosion is widely present in the pipelines of oil and gas production, causing significant corrosion damage. In this paper, a novel electrochemical cathodic-polarization method was carried out to accelerate the formation of CaCO3 scale on a X65 steel surface in a simulated solution containing scaling ions. Subsequently, pre-scaled X65 steel was placed in a high temperature and pressure autoclave to conduct corrosion weight-loss experiments and in situ electrochemical measurements. The study mainly compared the corrosion inhibition behavior of four quaternary ammonium salt corrosion inhibitors, pyridinium quaternary salt (BPC), quinolinium quaternary salt (BQC), 8-hydroxyquinolinium quaternary salt (BHQ) and pyridinium (1-chloromethyl naphthalene) quaternary salt (1-CPN), in a simulated oilfield scale under corrosive conditions. The results of the weight-loss experiments demonstrated that the inhibition efficiencies of the corrosion inhibitors from high to low were as follows: 1-CPN < BHQ < BQC < BPC. The in situ electrochemical measurements showed that the immersion time and type of corrosion inhibitor had a pronounced influence on the corrosion and corrosion inhibition behavior of X65 steel with CaCO3 coating. It was also proved using both EIS and PC that 1-CPN shows the best inhibition performance in all. Lastly, the inhibition mechanism of corrosion inhibitors at under-deposit conditions was analyzed via a surface morphology observation of SEM.
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Soil contamination with heavy metals from industrial and mining activities poses significant environmental and public health risks, necessitating effective remediation strategies. This review examines the utilization of sulfate-reducing bacteria (SRB) for bioremediation of heavy metal-contaminated soils. Specifically, it focuses on SRB metabolic pathways for heavy metal immobilization, interactions with other microorganisms, and integration with complementary remediation techniques such as soil amendments and phytoremediation. We explore the mechanisms of SRB action, their synergistic relationships within soil ecosystems, and the effectiveness of combined remediation approaches. Our findings indicate that SRB can effectively immobilize heavy metals by converting sulfate to sulfide, forming stable metal sulfides, thereby reducing the bioavailability and toxicity of heavy metals. Nevertheless, challenges persist, including the need to optimize environmental conditions for SRB activity, address their sensitivity to acidic conditions and high heavy metal concentrations, and mitigate the risk of secondary pollution from excessive carbon sources. This study underscores the necessity for innovative and sustainable SRB-based bioremediation strategies that integrate multiple techniques to address the complex issue of heavy metal soil contamination. Such advancements are crucial for promoting green mining practices and environmental restoration.
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Biodegradação Ambiental , Metais Pesados , Microbiologia do Solo , Poluentes do Solo , Sulfatos , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Sulfatos/metabolismo , Bactérias Redutoras de Enxofre/metabolismo , Bactérias/metabolismo , Mineração , Solo/químicaRESUMO
Hypervirulent Klebsiella pneumoniae (hvKP) is increasingly reported worldwide as a major clinical and public health threat. The virulence of hvKP is attributed largely to the carriage of virulence plasmids (KpVPs). To date, two dominant types of KpVP have been identified, namely, KpVP-1 and KpVP-2. In this study, we reported two hvKP strains from bloodstream infections that carry highly identical virulence plasmids that exhibited <40% coverage compared with KpVP-1 and KpVP-2. This novel virulence plasmid was designated KpVP-3. The two hvKP have different genetic backgrounds, which belonged to ST29-K54 and ST111-K63, respectively. They were both positive for the string test, highly virulent on the Galleria mellonella infection model, and possess high-level macrophage-killing resistance in vitro. Apart from the intrinsic non-susceptibility to ampicillin, both strains were susceptible to commonly used antibiotics. The virulence plasmid carried virulence genes rmpADC, iroBCDN (iro1), and the ybt locus (ybt4) which was not present on either KpVP-1 or KpVP-2. It did not carry antimicrobial resistance genes but carried an incomplete conjugation machinery containing only the traH and traF genes. The KpVP-3 plasmid was stably maintained in both hvKP strains and could not be eliminated with SDS treatment or by serial passage on stress-free agar plates. KpVP-3 was non-self-transmissible under experimental conditions. Data mining suggested KpVP-3-type plasmids have emerged in different countries including China, Australia, and the USA. The emergence of this novel virulence plasmid might pose a potential threat to public health. Heightened efforts are required to study its dissemination mechanism.
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Infecções por Klebsiella , Klebsiella pneumoniae , Humanos , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidade , Plasmídeos/genética , Virulência/genética , Fatores de Virulência/genéticaRESUMO
PURPOSE: To evaluate the recurrence rate of primary hyperhidrosis (PH) after computed tomography (CT)-guided radiofrequency sympathectomy (RFS) and identify risk factors associated with recurrence. MATERIALS AND METHODS: A total of 290 patients with PH who underwent CT-guided RFS were included in this retrospective cohort study. The electronic medical record was reviewed for patients' information and procedural parameters. Follow-ups were conducted for recurrence rate, and Hyperhidrosis Disease Severity Scale was used to assess presence or absence of recurrence. Stepwise regression and the least absolute shrinkage and selection operator regression algorithms were used for feature selection. RESULTS: The recurrence rate 1 year after procedure was 17.6%. Male (hazard ratio [HR], 2.35; 95% confidence interval [CI], 1.08-5.15), low postoperative palm or foot temperature (HR, 0.77; 95% CI, 0.60-0.98), high postoperative heart rate (HR, 1.06; 95% CI, 1.02-1.10), low preoperative and postoperative hospital anxiety and depression score difference (HR, 0.59; 95% CI, 0.43-0.80), and the absence of compensatory hyperhidrosis immediately after procedure (HR, 0.46; 95% CI, 0.22-0.98) were established as independent factors affecting prognosis. A nomogram was built accordingly. The C indices of the training and testing sets were 0.773 and 0.659, respectively. CONCLUSIONS: Follow-up results showed that the recurrence rate of PH treated with CT-guided RFS was low. This study constructed and validated a nomogram to predict the recurrence of PH 1 year after CT-guided RFS, which is convenient for interventionalists to evaluate accurately the prognosis of patients postoperatively and to identify high-risk patients who need more active treatment.
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Hiperidrose , Nomogramas , Humanos , Masculino , Resultado do Tratamento , Estudos Retrospectivos , Simpatectomia/efeitos adversos , Simpatectomia/métodos , Hiperidrose/diagnóstico por imagem , Hiperidrose/cirurgia , Tomografia Computadorizada por Raios X/métodos , Complicações Pós-Operatórias/cirurgiaRESUMO
Comparing with the effect of the average climate change on vegetation phenology, the impacts of extreme climate events remain unclear, especially considering their characteristic cumulative and time-lag effects. Using solar-induced chlorophyll fluorescence (SIF) satellite records, we investigated the cumulative and time-lag effects of drought and heat events on photosynthesis, particularly for the end date of autumn photosynthesis (EOP), in subtropical vegetation in China. Our results showed a negative effect of drought on the delay of EOP, with the cumulative effect on 30.12% (maximum continuous dry days, CDD), 34.82% (dry days, DRD), and 26.14% (dry period, DSDI) of the study area and the general time-lag effect on 50.73% (maximum continuous dry days), 56.61% (dry days), and 47.55% (dry period) of the study area. The cumulative and lagged time were 1-3 months and 2-3 months, respectively. In contrast, the cumulative effect of heat on EOP was observed in 16.27% (warm nights, TN90P), 23.66% (moderate heat days, TX50P), and 19.19% (heavy heat days, TX90P) of the study area, with cumulative time of 1-3 months. The lagged time was 3-4 months, detected in 31.02% (warm nights), 45.86% (moderate heat days), and 36.52% (heavy heat days) of the study area. At the vegetation community level, drought and heat had relatively rapid impacts on EOP in the deciduous broadleaved forest, whereas evergreen forests and bushes responded to heat slowly and took a longer time. Our results revealed that drought and heat have short-term cumulative and time-lag effects on the EOP of subtropical vegetation in China, with varying effects among different vegetation types. These findings provide new insights into the effect of drought and heat on subtropical vegetation and confirm the need to consider these effects in the development of prediction models of autumn phenology for subtropical vegetation.
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Secas , Temperatura Alta , Fotossíntese , Florestas , Luz Solar , Estações do Ano , China , Ecossistema , Mudança ClimáticaRESUMO
Chrysanthemum (Chrysanthemum morifolium Ramat.) is one of the largest cut flowers in the world. Phosphate transporter Pht1 family member CmPht1;2 protein (CmPT2) plays an important role in response to low-phosphate (LP) stress in chrysanthemum. Post-translational modification (PTM) can modulate the function of proteins in multiple ways. Here, we used yeast and rice systems to study the role of putative PTM in CmPT2 by determining the effect of mutation of key amino acid residues of putative glycosylation, phosphorylation, and myristoylation sites. We chose nine amino acid residues in the putative PTM sites and mutated them to alanine (A) (Cmphts). CmPT2 recovered the growth of yeast strain MB192 under LP conditions. However, G84A, G222A, T239A, Y242A, and N422A mutants could not grow normally under LP conditions. Analysis of phosphorus absorption kinetics showed that the Km of CmPT2 was 65.7 µM. Among the nine Cmphts, the expression of five with larger Km (124.4-397.5 µM) than CmPT2 was further evaluated in rice. Overexpression of CmPT2-OE increased plant height, effective panicle numbers, branch numbers, and yield compared with that of wild type 'Wuyunjing No. 7' (W7). Overexpression of Cmphts-OE led to decreased plant height and effective panicle numbers compared with that of the CmPT2-OE strain. The Pi content in roots of CmPT2-OE was higher than that of the W7 under both high (normal) phosphate (HP) and LP conditions. However, the Pi content in the leaves and roots was significantly lower in the N422A-OE strain than in the CmPT2-OE strain under both HP and LP conditions. Under LP conditions, the phosphorus starvation response (PSR) genes in CmPT2-OE were inhibited at the transcription level. The expression patterns of phosphorus-related genes in T239A, Y242A, and N422A-OE under LP conditions were different from those of CmPT2-OE. In conclusion, these five post-translational modification residues of CmPT2 play key roles in modulating the function of CmPT2. This work boosters our understanding of the function of phosphate transporters and provides genetic resources for improving the efficiency of phosphorus utilization in crop plants.
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Proteínas Fúngicas , Oryza , Proteínas de Plantas , Saccharomyces cerevisiae , Aminoácidos/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/genética , Oryza/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , Fósforo/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Processamento de Proteína Pós-Traducional , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismoRESUMO
Phototherapy has the advantages of being a highly targeted, less toxic, less invasive, and repeatable treatment, compared with conventional treatment methods such as surgery, chemotherapy, and radiotherapy. The preparation strategies are significant in order to determine the physical and chemical properties of nanoparticles. However, choosing appropriate preparation strategies to meet applications is still challenging. This review summarizes the recent progress of preparation strategies in organic nanoparticles, mainly focusing on the principles, methods, and advantages of nanopreparation strategies. In addition, typical examples of cancer phototherapeutics are introduced in detail to inform the choice of appropriate preparation strategies. The relative future trend and outlook are preliminarily proposed.
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Nanopartículas , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Nanopartículas/uso terapêutico , FototerapiaRESUMO
Chiral pesticides account for 30% of pesticides. Pesticides are inevitably leached into the groundwater by runoff. At the watershed level, the distribution characteristics of enantiomers in sediments collected from the river network of an agricultural area near the middle and lower reaches of the Yangtze River were tested, and their potential correlations with the physicochemical properties and microbial communities of the sediments were analyzed. The sediment pollution was serious at sites 8 and 9, with their pollution source possibly being agricultural or industrial sewage. Moreover, there were higher cumulative contents of pesticide residues at sites 4, 8, and 9. Specifically, Cycloxaprid was the most detected chiral pesticide in the study area, followed by Dinotefuran and Diclofop-methyl. Additionally, Ethiprole and Difenoconazole had strong enantioselectivity in the study area. Interestingly, the enantiomers of some chiral pesticides, such as Tebuconazole, had completely different distributions at different sites. Pearson correlation analysis showed that sediment catalase and microbial biomass carbon were important factors for enantioselectivity of chiral pesticides. The effect of sediment physicochemical properties on enantioselective distribution was achieved by influencing the microorganisms in the sediment. Furthermore, the enantioselective distribution of Tebuconazole was closely related to the genus Arenimonas. Overall, the enantioselective distribution of most of the chiral pesticides was positively correlated with the prokaryotic microbial community. This study provides empirical support for agricultural non-point source pollution caused by chiral pesticides, and also lays a research foundation for exploring the factors that affect the fate of chiral pesticides in the environment.
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Água Subterrânea , Resíduos de Praguicidas , Praguicidas , Resíduos de Praguicidas/análise , Praguicidas/análise , Rios , EstereoisomerismoRESUMO
The use of infrared spectroscopy to augment decision-making in histopathology is a promising direction for the diagnosis of many disease types. Hyperspectral images of healthy and diseased tissue, generated by infrared spectroscopy, are used to build chemometric models that can provide objective metrics of disease state. It is important to build robust and stable models to provide confidence to the end user. The data used to develop such models can have a variety of characteristics which can pose problems to many model-building approaches. Here we have compared the performance of two machine learning algorithms - AdaBoost and Random Forests - on a variety of non-uniform data sets. Using samples of breast cancer tissue, we devised a range of training data capable of describing the problem space. Models were constructed from these training sets and their characteristics compared. In terms of separating infrared spectra of cancerous epithelium tissue from normal-associated tissue on the tissue microarray, both AdaBoost and Random Forests algorithms were shown to give excellent classification performance (over 95% accuracy) in this study. AdaBoost models were more robust when datasets with large imbalance were provided. The outcomes of this work are a measure of classification accuracy as a function of training data available, and a clear recommendation for choice of machine learning approach.
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Algoritmos , Aprendizado de MáquinaRESUMO
In this work, we employed waste activated sludge (WAS) as carbon source to prepare ultrahigh specific surface area (SSA) biopolymers-based carbons (BBCs) through alkali (KOH) treatment coupled to pyrolysis strategy. Before the pyrolysis process, the involvement of KOH made a great recovery of soluble biopolymers from WAS, resulting in highly-efficient catalytic pyrolysis. The Brunner-Emmett-Teller and pore volume of BBCs prepared at 800°C (BBC800) reached the maximum at 2633.89 m2·g-1 and 2.919 m3·g-1, respectively. X-ray photoelectron spectroscopy suggested that aromatic carbon in the form of C=C was the dominant fraction of C element in BBCs. The N element in BBCs were composed of pyrrolic nitrogen and pyridinic nitrogen at 700°C, while a new graphitic nitrogen appeared over 800°C. As a refractory pollutant of wastewater treatment plants, tetracycline (TC) was selected to evaluate adsorption performance of BBCs. The adsorption behavior of BBCs towards TC was conformed to the pseudo-second-order kinetic and the Langmuir models, signifying that chemisorption of monolayers was dominant in TC adsorption. The adsorption capacity of BBC800 reached the maximum at 877.19 mg·g-1 for 90 min at 298 K. Thermodynamic analysis indicated that the adsorption process was endothermic and spontaneous. Hydrogen bonding and π-π stacking interaction were mainly responsible for TC adsorption, and interfacial diffusion was the main rate-control step in adsorption process. The presence of soluble microbial products (SMPs) enhanced TC removal. This work provided a novel strategy to prepare bio-carbon with ultrahigh SSA using WAS for highly-efficient removal of organic pollutants.
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Esgotos , Poluentes Químicos da Água , Adsorção , Álcalis , Biopolímeros , Carbono , Carvão Vegetal , Cinética , Pirólise , Poluentes Químicos da Água/análiseRESUMO
The separation of rural families in China has resulted in a large number of "left-behind" children, who are frequently subjected to sexual abuse. Failing and insufficient tutelage owing to the migration of parents into cities and the distinctive rural living environment (e.g. drab and enclosed habitats) are the major causes of the high incidence of sexual abuse against left-behind children. We have applied the concept of "ritualized law" (lihua de fa) to delineate the powerless position of the state legal system vis-á-vis the sexual assaults committed against left-behind children in rural China. Pervasive and ingrained traditional customs and rituals, and the intermediary relationships between familiar people, have restricted the reach of the judicial system in rural areas. Moreover, deeply rooted traditional beliefs and the primacy of interpersonal (and inter-familiar) harmony over legal and formal institutions have weakened the legal system and, in many cases, allowed sexual offenders to avoid prosecution.
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Abuso Sexual na Infância/etnologia , Separação da Família , População Rural , Adolescente , Criança , Abuso Sexual na Infância/legislação & jurisprudência , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Masculino , Pesquisa Qualitativa , MigrantesRESUMO
The ceria-based catalyst incorporated with Cr and a trace amount of Rh (Cr0.19Rh0.06CeOz) was prepared and the reversible redox performances and oxidation catalysis of CO and alcohol derivatives with O2 at low temperatures (<373 K) were investigated. In situ X-ray absorption fine structure (XAFS), ambient-pressure X-ray photoelectron spectroscopy (AP-XPS), high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM)-EDS/EELS and temperature-programmed reduction/oxidation (TPR/TPO) revealed the structures and redox mechanisms of three metals in Cr0.19Rh0.06CeOz: dispersed Rh3+δ species (<1 nm) and Cr6-γO3-x nanoparticles (â¼1 nm) supported on CeO2 in Cr0.19Rh0.06CeOz were transformed to Rh nanoclusters, Cr(OH)3 species and CeO2-x with two Ce3+-oxide layers at the surface in a concerted activation manner of the three metal species with H2.
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Heavy metal contamination of soil has become a serious global issue because of their persistence in the environment and the non-biodegradable nature leading to their accumulation to toxic levels. In order to achieve early warning and prevent soil quality from deteriorating, it is necessary to select suitable indices to diagnose heavy metal pollution. Microbiological indices for monitoring soil pollution by heavy metals are gaining attention. However, the related researches are scattered, and critical review is imperative. This review is mainly to provide readers with an in-depth understanding of the merits and limitations of microbiological indices for heavy metals contaminated and remediated soils. Microbiological indicators include microbial abundance, community diversity and structure, functional activity. The changes of different microbiological indices and the mechanism of microbial response to heavy metal stress in soils are comprehensively summarized. Furthermore, research gaps and future directions of the microbial ecotoxicological diagnosis of soil contamination by heavy metals are also proposed and discussed.
Assuntos
Metais Pesados , Poluentes do Solo , Monitoramento Ambiental , Poluição Ambiental , SoloRESUMO
Seeking utilization of allied health services (AHS) has significant implications for psychological distress self-management. However, utilization of AHS by Chinese female migrant workers (FMWs) has not received enough attention. This study, therefore, aims to explore what contributes to FMWs' proactiveness in utilizing AHS. A cross-sectional study was conducted to collect data in terms of socio-demographic characteristics, work-related characteristics and AHS accessibility. A logistic regression model was adopted to examine association of these predictors with proactiveness in seeking AHS. 992 FMWs with psychological distress were interviewed with stratified multiple-stage sampling. The results indicated that Basic Public Health Services (BPHS) is a salient predictor affecting proactiveness in seeking AHS. BPHS includes psychological counseling (Odds Ratio (OR) =2.401, 95% Confidence Interval (CI) =1.284-4.490, p = 0.006), psychotherapy (OR = 2.063, 95% CI = 1.438-2.960, p = 0.000) and health knowledge lectures (OR = 1.613, 95% CI = 1.115-2.333, p = 0.011). Moreover, sampled participants under 25 and those who received education for more than 9 years are more likely to seek AHS compared with other groups. In addition, proactiveness in seeking AHS is clearly associated with working hours per day. The probability is only 31.1% for those working more than 12 h per day to seek AHS actively compared with those working below 8 h (95% CI = 0.119-0.812, p = 0.017). There are no differences between those with 8-12 working hours and those working less than 8 h (OR = 1.100, 95% CI = 0.798-1.518, p = 0.560). The present findings suggest that policies be made to improve the coverage of BPHS and to provide specified AHS to meet the increasing demand of different social groups.