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1.
J Transl Med ; 22(1): 128, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308276

RESUMO

BACKGROUND: DNMT3L is a crucial DNA methylation regulatory factor, yet its function and mechanism in hepatocellular carcinoma (HCC) remain poorly understood. Bioinformatics-based big data analysis has increasingly gained significance in cancer research. Therefore, this study aims to elucidate the role of DNMT3L in HCC by integrating big data analysis with experimental validation. METHODS: Dozens of HCC datasets were collected to analyze the expression of DNMT3L and its relationship with prognostic indicators, and were used for molecular regulatory relationship evaluation. The effects of DNMT3L on the malignant phenotypes of hepatoma cells were confirmed in vitro and in vivo. The regulatory mechanisms of DNMT3L were explored through MSP, western blot, and dual-luciferase assays. RESULTS: DNMT3L was found to be downregulated in HCC tissues and associated with better prognosis. Overexpression of DNMT3L inhibits cell proliferation and metastasis. Additionally, CDO1 was identified as a target gene of DNMT3L and also exhibits anti-cancer effects. DNMT3L upregulates CDO1 expression by competitively inhibiting DNMT3A-mediated methylation of CDO1 promoter. CONCLUSIONS: Our study revealed the role and epi-transcriptomic regulatory mechanism of DNMT3L in HCC, and underscored the essential role and applicability of big data analysis in elucidating complex biological processes.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Big Data , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA/genética , Neoplasias Hepáticas/genética , Regiões Promotoras Genéticas/genética
2.
Ann Surg ; 277(6): 912-919, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36177847

RESUMO

OBJECTIVE: To estimate the global and regional prevalence and cases of abdominal aortic aneurysms (AAAs) in 2019 and to evaluate major associated factors. BACKGROUND: Understanding the global prevalence of AAA is essential for optimizing health services and reducing mortality from reputed AAA. METHODS: PubMed, MEDLINE, and Embase were searched for articles published until October 11, 2021. Population-based studies that reported AAA prevalence in the general population, defined AAA as an aortic diameter of 30 mm or greater with ultrasonography or computed tomography. A multilevel mixed-effects meta-regression approach was used to establish the relation between age and AAA prevalence for high-demographic sociodemographic index and low-and middle-sociodemographic index countries. Odds ratios of AAA associated factors were pooled using a random-effects method. RESULTS: We retained 54 articles across 19 countries. The global prevalence of AAA among persons aged 30 to 79 years was 0.92% (95% CI, 0.65-1.30), translating to a total of 35.12 million (95% CI, 24.94-49.80) AAA cases in 2019. Smoking, male sex, family history of AAA, advanced age, hypertension, hypercholesterolemia, obesity, cardiovascular disease, cerebrovascular disease, claudication, peripheral artery disease, pulmonary disease, and renal disease were associated with AAA. In 2019, the Western Pacific region had the highest AAA prevalence at 1.31% (95% CI, 0.94-1.85), whereas the African region had the lowest prevalence at 0.33% (95% CI, 0.23-0.48). CONCLUSIONS: A substantial proportion of people are affected by AAA. There is a need to optimize epidemiological studies to promptly respond to at-risk and identified cases to improve outcomes.


Assuntos
Aneurisma da Aorta Abdominal , Hipertensão , Pneumopatias , Humanos , Masculino , Fatores de Risco , Prevalência , Fumar , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/epidemiologia , Ultrassonografia
3.
J Clin Nurs ; 32(15-16): 5219-5229, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36448208

RESUMO

AIMS AND OBJECTIVES: To explore the acceptances and associated influences of organ donation in mainland China. BACKGROUND: The shortage of organ donors has limited the development of organ transplantation in China. It is important to recognise the target population who has high intention to donate their organs may change the status. DESIGN: We conducted a cross-sectional, multi-stage sampling study collected demographic data and individuals' willingness to accept organ donation. METHODS: A stepwise linear regression analysis was adopted to evaluate the factors related to the attitudes toward organ donation. RESULTS: We collected 11,031 valid samples for the survey. The willingness to donate organs among Chinese residents averaged 56.93 points. To be specific, males (ß = -.03), religious believers (ß = -.01) and parents with a different number of children (all: ß = -.04) are less willing to donate their organs. Respondents who live in an urban area (ß = .03), have higher education level (High school or junior college ß = .04, Bachelor degree or above ß = .09), feel anxious (mild, moderate ß = .02), feel pressured (moderate, severe ß = .08), have higher scores of the Short-Form Health Literacy Instrument (HLS-SF12) (ß = .31), The Self-Management Scale (SHMS) (ß = .16), EuroQol Five Dimensions Questionnaire (EQ-5D) (ß = .04) and EuroQol Visual Analogue Scale (EQ-VAS) (ß = .24), are more positive to donate. CONCLUSIONS: This study firstly discusses the public acceptance of organ donation through a nationwide sample around China. In this study, we discovered that Chinese residents' acceptance level of organ donation and that gender, house, anxiety, pressure, social support and health literacy were the main influencing factors on residents' attitudes. RELEVANCE TO CLINICAL PRACTICE: To figure out the Chinese public acceptance and its influencing factors of organ donation can help nurse transplant coordinators to recognise the target population and the obstacles of organ donation. PATIENT OR PUBLIC CONTRIBUTION: At the phase of collecting data, participants were recruited to fill the questionnaires.


Assuntos
Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Masculino , Criança , Humanos , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários , China
4.
J Proteome Res ; 21(11): 2635-2646, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36264770

RESUMO

Cerebral infarction (CI) remains a major cause of high mortality and long-term disability worldwide. The exploration of biomarkers and pathogenesis is crucial for the early diagnosis of CI. Although the understanding of metabolic perturbations underlying CI has increased in recent years, the relationship between altered metabolites and disease pathogenesis has only been partially elucidated and requires further investigation. In this study, we performed an integrated metabolomics and lipidomics analysis on 59 healthy subjects and 47 CI patients. Ultimately, 49 metabolite and 68 lipid biomarkers were identified and enriched in 24 disturbed pathways. The metabolic network revealed a significant interaction between altered lipids and other metabolites. Using receiver operating characteristic curve (ROC) analysis, a panel of three polar metabolites and seven lipids was optimized in the training set, which included taurine, oleoylcarnitine, creatinine, PE(22:6/P-18:0), Cer 34:2, GlcCer(d18:0/18:0), DG 44:0, LysoPC(16:0), 22:6-OH/LysoPC, and TAG58:7-FA22:4. Subsequently, a support vector machine (SVM) model was constructed and validated, which showed excellent predictive ability in the validation set. Thereby, the integrated metabolomics and lipidomics approach could contribute to a comprehensive understanding of the metabolic dyshomeostasis associated with the pathogenesis of underlying CI. The present research may promote a deeper understanding and early diagnosis of CI in the clinic. All raw data were deposited in PRIDE (PXD036199).


Assuntos
Lipidômica , Metabolômica , Humanos , Redes e Vias Metabólicas , Biomarcadores/metabolismo , Diagnóstico Precoce , Infarto Cerebral/diagnóstico
5.
Environ Sci Technol ; 56(12): 7564-7577, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35579536

RESUMO

Carbonaceous emissions from wildfires are a dynamic mixture of gases and particles that have important impacts on air quality and climate. Emissions that feed atmospheric models are estimated using burned area and fire radiative power (FRP) methods that rely on satellite products. These approaches show wide variability and have large uncertainties, and their accuracy is challenging to evaluate due to limited aircraft and ground measurements. Here, we present a novel method to estimate fire plume-integrated total carbon and speciated emission rates using a unique combination of lidar remote sensing aerosol extinction profiles and in situ measured carbon constituents. We show strong agreement between these aircraft-derived emission rates of total carbon and a detailed burned area-based inventory that distributes carbon emissions in time using Geostationary Operational Environmental Satellite FRP observations (Fuel2Fire inventory, slope = 1.33 ± 0.04, r2 = 0.93, and RMSE = 0.27). Other more commonly used inventories strongly correlate with aircraft-derived emissions but have wide-ranging over- and under-predictions. A strong correlation is found between carbon monoxide emissions estimated in situ with those derived from the TROPOspheric Monitoring Instrument (TROPOMI) for five wildfires with coincident sampling windows (slope = 0.99 ± 0.18; bias = 28.5%). Smoke emission coefficients (g MJ-1) enable direct estimations of primary gas and aerosol emissions from satellite FRP observations, and we derive these values for many compounds emitted by temperate forest fuels, including several previously unreported species.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Incêndios Florestais , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Gases , Tecnologia de Sensoriamento Remoto
6.
Geophys Res Lett ; 49(18): e2022GL099175, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36591326

RESUMO

Aerosol mass extinction efficiency (MEE) is a key aerosol property used to connect aerosol optical properties with aerosol mass concentrations. Using measurements of smoke obtained during the Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) campaign we find that mid-visible smoke MEE can change by a factor of 2-3 between fresh smoke (<2 hr old) and one-day-old smoke. While increases in aerosol size partially explain this trend, changes in the real part of the aerosol refractive index (real(n)) are necessary to provide closure assuming Mie theory. Real(n) estimates derived from multiple days of FIREX-AQ measurements increase with age (from 1.40 - 1.45 to 1.5-1.54 from fresh to one-day-old) and are found to be positively correlated with organic aerosol oxidation state and aerosol size, and negatively correlated with smoke volatility. Future laboratory, field, and modeling studies should focus on better understanding and parameterizing these relationships to fully represent smoke aging.

7.
J Clin Nurs ; 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253950

RESUMO

AIMS AND OBJECTIVES: This review aims to synthesize the available evidence of what patients experience when infected with COVID-19, both in hospital and post-discharge settings. DESIGN: This review was conducted using the Joanna Briggs Institute (JBI) methodology for qualitative systematic reviews and evidence synthesis. Reporting of results was presented according to the Enhancing Transparency in Reporting the Synthesis of Qualitative Research (ENTREQ) checklist. BACKGROUND: Coronavirus disease 2019 (COVID-19) continues to be a public health crisis worldwide. Many patients diagnosed with COVID-19 have varied levels of persisting mental disorders. Previous studies have reported the degree, prevalence and outcome of psychological problems. Minimal research explored the experience of patients with long COVID. The real-life experience of patients with COVID-19 from diagnosis to post-discharge can deepen the understanding of nurses, physicians and policymakers. METHODS: All studies describing the experience of patients were included. Two authors independently appraised the methodological quality of the included studies using the JBI Critical Appraisal Checklist for Qualitative Research 2020. RESULTS: This systematic review aggregated patients' experience of being diagnosed with COVID-19 in both hospitalized and post-discharge settings. Finally, 17 studies met inclusion criteria and quality appraisal guidelines. The selected studies in the meta-synthesis resulted in 12 categories, and further were concluded as five synthesized findings: physical symptoms caused by the virus, positive and negative emotional responses to the virus, positive coping strategies as facilitators of epidemic prevention and control, negative coping strategies as obstacles of epidemic prevention and control, and unmet needs for medical resource. CONCLUSIONS: The psychological burden of patients diagnosed with COVID-19 is heavy and persistent. Social support is essential in the control and prevention of the epidemic. Nurses and other staff should pay more attention to the mental health of the infected patients both in and after hospitalization. RELEVANCE TO CLINICAL PRACTICE: Nurses should care about the persistent mental trauma of COVID-19 survivors and provide appropriate psychological interventions to mitigate the negative psychological consequences of them. Besides, nurses, as healthcare professionals who may have the most touch with patients, should evaluate the level of social support and deploy it for them. It is also needed for nurses to listen to patient's needs and treat them with carefulness and adequate patience in order to decrease the unmet needs of patients.

8.
J Nurs Manag ; 30(8): 3958-3971, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36194367

RESUMO

AIM: The aim of this work is to critically appraise and synthesize the qualitative studies on the experiences, perspectives, and consequences of pregnant women experiencing motherhood during the COVID-19 pandemic. BACKGROUND: The COVID-19 pandemic has posed a threat to the health of pregnant women. Such a pandemic disrupted their routine care, as well as normal daily life. However, little is known about their coping strategies to the changes brought by COVID-19. EVALUATION: A qualitative systematic review was conducted according to the Enhancing Transparency in Reporting the Synthesis of Qualitative Research (ENTREQ) checklist. A meta-aggregative approach rooted in pragmatism and Husserlian transcendental phenomenology was used to synthesize the findings. Dependability and credibility of both study findings and synthesized findings were appraised by Joanna Briggs Institute (JBI) ConQual process. KEY ISSUES: Key issues include (a) pregnant women experienced changes in routine care, (b) pregnant women used a range of strategies to cope with the consequence of the pandemic, (c) pregnant women struggled to embrace motherhood, and (d) pregnant women received different levels of social support. CONCLUSION: Facing challenges caused by the pandemic, pregnant women used a variety of strategies to cope with and adapt to the changes, but sometimes the adaption is limited. Emotional, instrumental, and informational support should be provided to them in an accessible way. IMPLICATIONS FOR NURSING MANAGEMENT: As an essential part of policymakers, nursing managers should consider the balance between restriction and the accessibility of maternity care. It is also crucial for them to consider how to provide necessary support in an accessible way.


Assuntos
COVID-19 , Serviços de Saúde Materna , Feminino , Gravidez , Humanos , COVID-19/epidemiologia , Pandemias , Período Pós-Parto , Pesquisa Qualitativa
9.
Pharmacol Res ; 170: 105516, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33636350

RESUMO

Amid the globalization of traditional Chinese medicine (TCM), the English translation of related texts is in full swing. Several representative international organizations in fields regarding standardization and healthcare, one after another, have published a series of international standards for TCM nomenclature. With these efforts, the internationalization of TCM has been dramatically advanced. When selecting parallel texts for reference, translators need to be aware of key factors influencing the English translation of TCM terms in international standards, including the distinctive characteristics of this discipline and relevant influences of international standard makers. In this way, proper standards and reasonable English expression can be chosen for specific terms, thus stimulating the effective use of TCM nomenclature with consensus.


Assuntos
Medicina Tradicional Chinesa/normas , Terminologia como Assunto , Tradução , Vocabulário Controlado , Consenso , Humanos , Cooperação Internacional
10.
Ecotoxicol Environ Saf ; 220: 112404, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34111660

RESUMO

Cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg) and arsenic (As) are potent toxicants to human health via dietary intake. It is imperative to establish accurate soil thresholds based on soil-plant transfer models and food safety standards for safe agricultural production. This study takes rice genotypes and soil properties into account to derive soil thresholds for five heavy metal(loid)s using the bioconcentration factors (BCF) and species sensitivity distribution (SSD) based on the food safety standard. The BCF generated from two paddy soils was calculated to investigate the sensitivity of heavy metal accumulation in nine rice cultivars in a greenhouse pot experiment. Then, empirical soil-plant transfer models were developed from a middle-sensitivity rice cultivar (Denong 2000, one selected from nine rice) grown in nineteen paddy soils with various soil properties under a proper exogenously metal(loid)s concentration gradient. After normalization, hazardous concentrations from the fifth percentile (HC5) were calculated from the SSD curves, and the derived soil thresholds were obtained from HC5 prediction models that based on the combination of pH and organic carbon (OC) or cation exchange capacity (CEC). The soil Cd threshold derived based on pH and organic carbon (pH < 7.5, OC ≥ 20 g kg-1) was 1.3-fold of those only considering pH, whereas the Pb threshold (pH > 6, CEC ≥ 20 cmolc kg-1) was 3.1 times lower than the current threshold. The derived thresholds for five elements were validated to be reliable through literature data and field experiments. The results suggested that deriving soil heavy metal(loid)s threshold using SSD method and local food safety standards is feasible and also applicable to other crops as well as other regions with potential health risks of toxic elements contamination in agricultural production.


Assuntos
Metais Pesados/normas , Oryza/crescimento & desenvolvimento , Poluentes do Solo/normas , Solo/normas , Arsênio/análise , Arsênio/normas , Cádmio/análise , Cádmio/normas , Cromo/análise , Cromo/normas , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/normas , Inocuidade dos Alimentos , Humanos , Chumbo/análise , Chumbo/normas , Mercúrio/análise , Mercúrio/normas , Metais Pesados/análise , Oryza/química , Oryza/genética , Solo/química , Poluentes do Solo/análise
11.
J Sci Food Agric ; 101(9): 3843-3853, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33336495

RESUMO

BACKGROUND: Rice-crayfish coculture (RC) uses 10% of the paddy field area for crayfish ditches, with rice cultivated in the remaining area, providing staple carbohydrates alongside fish rich in protein and essential oils. These systems rely on complex interactions, involving nutrient cycling, fish feeding, soil physicochemical modification, and insect-pest predation, and have important socio-economic effects. Past studies have considered only one or a few of these aspects pertinent to food system sustainability, and there remains a need for an integrated assessment of RC systems. In this mini-review, we collate data from two field experiments and three field surveys published across eight papers to synthesize the overall sustainability of RC systems in Jianghan Plain in China. RESULTS: In deep groundwater fields, the RC rice yield was 30-55% lower than for typical rice-rapeseed (RR) rotations, while CH4 emission and pesticide use were 41-96% and 50% lower, respectively. In shallow groundwater fields, RC rice yield was similar to typical rice monoculture (RM) cultivation, while CH4 emission and pesticide use were 28-41% and 17% lower for RC cultivation. Field survey data indicated that RC can improve soil nutrient and organic matter content significantly compared with RM cultivation, and also increase the diversity of fauna and flora in the paddy field whilst reducing the incidence of chilo suppressalis (a major rice pest). Feed inputs to RC systems increased crayfish yield by 31-71% and reduced the fraction of N inputs lost to the environment from 71% to 41%. CONCLUSION: We conclude that RC systems with feed inputs in areas with shallow groundwater can deliver improved food security, sustainability, and resilience through ecological intensification. © 2020 Society of Chemical Industry.


Assuntos
Astacoidea/crescimento & desenvolvimento , Oryza/crescimento & desenvolvimento , Animais , China , Técnicas de Cocultura , Produção Agrícola
12.
Ecotoxicol Environ Saf ; 170: 210-217, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30529915

RESUMO

The soil cadmium (Cd) availability and uptake by Tagetes patula grown in two soil types contaminated with Cd and amended with N fertilizer and wheat straw were studied in a pot-culture experiment. The results indicated that N fertilizer treatment (N) and N fertilizer plus straw treatment (NS) promoted T. patula growth, while straw treatment (S) decreased T. patula biomass relative to the control. NS and S treatments increased Cd mobility in the soil and facilitated its uptake by T. patula in Acidic Ferralsols (AF) and Calcaric Cambisols (CC), but the promotion effect was much greater in CC than in AF. The Cd concentrations in the Tagetes shoots in the S and NS treatments were 40% and 27% greater, respectively, than those in the control treatment for AF, and 111% and 80% greater, respectively, for CC. Decreases in soil pH and increases in dissoluble organic carbon concentration after adding N fertilizer and straw were associated with an increase in soil Cd availability and in Cd uptake by T. patula. The results indicate that the NS treatment can alter the soil microenvironment, increasing Cd bioavailability and thus facilitating Cd uptake by T. patula. This work highlights that the combined application of N fertilizer with straw may be a useful way to increase the phytoextraction efficiency of Cd-contaminated soil by the Cd-hyperaccumulator T. patula.


Assuntos
Cádmio/isolamento & purificação , Fertilizantes/análise , Nitrogênio/análise , Tagetes/metabolismo , Triticum , Concentração de Íons de Hidrogênio , Raízes de Plantas/metabolismo , Caules de Planta , Solo/química , Poluentes do Solo/isolamento & purificação
13.
Ecotoxicol Environ Saf ; 148: 418-425, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29101886

RESUMO

The interactions between plants and nanomaterials (NMs) can shed light on the environmental consequences of nanotechnology. We used the major crop plant rice (Oryza sativa L.) to investigate the uptake of gold nanoparticles (GNPs) coated with either negatively or positively charged ligands, over a 5-day period, in the absence or presence of one of two amino acids, aspartic acid (Asp) or lysine (Lys), acting as components of rice root exudates. The presence of Asp or Lys influenced the uptake and distribution of GNPs in rice, which depended on the electrical interaction between the coated GNPs and each amino acid. When the electrical charge of the amino acid was the same as that of the surface ligand coated onto the GNPs, the GNPs could disperse well in nutrient solution, resulting in increased uptake of GNPs into rice tissue. The opposite was true where the charge on the surface ligand was different from that on the amino acid, resulting in agglomeration and reduced Au uptake into rice tissue. The behavior of GNPs in the hydroponic nutrient solution was monitored in terms of agglomeration, particle size distribution, and surface charge in the presence and absence of Asp or Lys, which depended strongly on the electrostatic interaction. Results from this study indicated that the species of root exudates must be taken into account in assessing the bioavailability of nanomaterials to plants.


Assuntos
Ácido Aspártico/química , Ouro/metabolismo , Lisina/química , Nanopartículas Metálicas , Oryza/metabolismo , Transporte Biológico , Ligantes , Nanopartículas Metálicas/química , Tamanho da Partícula , Raízes de Plantas/metabolismo
14.
Ecotoxicol Environ Saf ; 147: 708-714, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28938141

RESUMO

Combinations of remediation technologies are needed to solve the problem of soil contamination in paddy rice, due to multiple potential toxic elements (PTEs). Two potential mitigation methods, water management and in-situ remediation by soil amendment, have been widely used in treatment of PTE-polluted paddy soil. However, the interactive relationship between soil amendment and water management, and its influence on the accumulation of PTEs in rice are poorly understood. Greenhouse pot experiments were conducted to examine the effects of phosphate amendment on Cd and Pb availability in soil and their influence on Cd and Pb uptake into rice, on Fe and P availability in soil, and on the alteration of Fe amount and compartment on root surface among different water management strategies. Results indicated that Cd and Pb content in the shoot and grain were significantly affected by the different water management strategies in nonamended soils, and followed the order: wetting irrigation > conventional irrigation > continuous flooding. The application of phosphate amendment significantly decreased the variations of Cd and Pb absorption in shoot and grain of rice among different water treatments. The reasons may be attributed to the enhancement of P availability and the decrease of Fe availability in soil, and the decreased variations of Fe2+/Fe3+ content in root coating after the application of phosphate amendment. These results suggested that the simultaneous use of phosphate amendment and continuous flooding to immobilize Cd and Pb, especially in acid paddy soils, should be avoided.


Assuntos
Irrigação Agrícola/métodos , Cádmio/análise , Recuperação e Remediação Ambiental/métodos , Chumbo/análise , Oryza/química , Poluentes do Solo/análise , Solo/química , Ácidos , China , Grão Comestível/química , Poluição Ambiental/prevenção & controle , Concentração de Íons de Hidrogênio , Modelos Teóricos , Oryza/crescimento & desenvolvimento , Raízes de Plantas/química
16.
J Environ Sci (China) ; 52: 141-150, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28254032

RESUMO

Hydroxyapatite (HAP) has been widely used to immobilize many cationic metals in water and soils. The specific reason why an increase in the surface area of HAP enhances cadmium (Cd) uptake, but has no effect on lead (Pb) uptake, is not clear. The aim of this study was to determine the factors causing the differences in sorption behavior between Cd and Pb by evaluating HAPs with different surface areas. We synthesized HAPs with two different surface areas, which were characterized by X-ray diffraction, N2 adsorption, and scanning electron microscopy, and then evaluated them as sorbents for Cd and Pb removal by testing in single and binary systems. The sorption capacity of large surface area HAP (1.85mmol/g) for Cd in the single-metal system was higher than that of small surface area HAP (0.64mmol/g), but there were no differences between single- and binary-metal solutions containing Pb. After the Cd experiments, the HAP retained a stable structure and intact morphology, which promotes the accessibility of reactive sites for Cd. However, a newly formed precipitate covered the surface and blocked the channels in the presence of Pb, which reduced the number of potential adsorption sites on HAP for Cd and Pb. Remediation experiments using Cd- and Pb-contaminated soil produced similar results to the solution tests. These results indicate that alterations of the structure and morphology during the reaction is an important factor influencing metal sorption to HAP.


Assuntos
Cádmio/química , Durapatita/química , Chumbo/química , Modelos Químicos , Poluentes do Solo/química , Adsorção , Solo/química
17.
Phys Chem Chem Phys ; 17(2): 888-95, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25407885

RESUMO

Si-doped hexagonal boron nitride nanosheets (Si-BNNS) and nanotubes (Si-BNNT) have been investigated by first-principle methods. The strong interaction between the silicon atom and the hexagonal boron nitride nanosheet or nanotube with a boron vacancy indicates that such nanocomposites should be very stable. The significant charge transfer from the Si-BNNS substrate to the O2 molecule, which could occupy the antibonding 2π* orbitals of O2, results in the activation of the adsorbed O2. The catalytic activity of the Si-BNNS for CO oxidation is explored and the calculated barrier (0.29 eV) of the reaction CO + O2→ CO2 + O is much lower than those on the traditional noble metals. This opens a new avenue to fabricate low cost and high activity boron nitride-based metal-free catalysts.

18.
Sci Total Environ ; 915: 170161, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38232847

RESUMO

China faces a dual challenge of improving air quality and reducing greenhouse gas (GHG) emissions. Stringent clean air actions gradually narrow the end-of-pipe (EOP) pollution control potential. Meanwhile, pursuing carbon peaking will reduce air pollution and health risks. However, the impact on air quality and health gains in individual Chinese provinces has not been assessed with a specific focus on local policies. Here, typical shared socio-economic pathways (SSPs) and local policies (i.e., business as usual, BAU; end-of-pipe controls, EOP; co-control mitigation, CCM) are combined to set three scenarios (i.e., BAU-SSP3, EOP-SSP4, CCM-SSP1). Under these three scenarios, we couple the Low Emissions Analysis Platform (LEAP) model, an air quality model and health risk assessment methodology to evaluate the characteristics of carbon peaking in Fujian Province. PM2.5 air quality and impacts on public health are assessed, using the metric of the deaths attributable to PM2.5 pollution (DAPP). The results show that energy-related CO2 emissions will only peak before 2030 in the CCM-SSP1 scenario. In this context, air pollutant emission pathways reveal that mitigation is limited under the EOP-SSP4 scenario, necessitating further mitigation under the CCM-SSP1 scenario. The annual average PM2.5 level is projected to be 16.5 µg·m-3 in 2035 with a corresponding decrease in DAPP of 297 (95 % confidence intervals: 217-308) compared with that of 2020. Despite the significant improvements in PM2.5 air quality and health gains under the CCM-SSP1 scenario, reaching the 5 µg·m-3 target of the World Health Organization (WHO) remains difficult. Furthermore, population aging will require stronger PM2.5 mitigation to enhance health gains. This study provides a valuable reference for other developing regions to co-control air pollution and GHGs.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Material Particulado/análise , Carbono/análise , Poluição do Ar/análise , Poluentes Atmosféricos/análise , China
19.
J Health Psychol ; : 13591053241246620, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38660775

RESUMO

COVID-19 has posed unprecedented challenges to the mental health of college students worldwide. We examined the trends in students' stress levels during and after China's first wave of COVID-19 outbreaks by analyzing their demographics, behavior, mental health status, career confidence, and Chinese Perceived Stress Scale (CPSS) scores. Our findings indicate an increase in students' stress levels since the COVID-19 onset, with more students experiencing higher stress levels after the first outbreak than during it (OR = 2.03, 95% CI 1.79, 2.30). Several factors were identified as being associated with higher CPSS scores, including higher class levels, residence in rural or town areas, low family income, and lack of familiarity with COVID-19, among others. Our study highlighted the urgency of developing and implementing effective strategies to cope with students' stress during and after a global pandemic.

20.
Carbohydr Polym ; 334: 122015, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553215

RESUMO

Developing large-scale hydrogels with high tensile strength and robust mechanical properties is an intricate challenge of great industrial significance. In this study, we demonstrate an efficient method for producing nanocomposite hydrogels with extraordinary mechanical properties. Our approach involves a two-step process: an initial stage of pre-cross-linking boron nitride (BN)-enriched pre-gel sodium alginate, followed by cross-linking with metal ions. In stark contrast to conventional sodium alginate hydrogels (SA), our newly formulated 'BS hydrogel' exhibited an impressive tensile strength exceeding 41 MPa and improved thermal resistance. Moreover, the reconstituted BS hydrogel exhibited tensile strengths ranging from 47 to 96 MPa and elastic moduli ranging from 199 to 1184 MPa, depending on the cross-linking metal ions. These findings indicate the multifaceted potential of the BS hydrogel, which is poised to revolutionize many applications and represents a significant step forward in hydrogel technology for industrial applications.

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