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1.
Environ Pollut ; 334: 122139, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37419208

RESUMO

The discharge of a large amount of flotation reagents wastewater can cause significant environmental pollution. In this study, NiO/La-NaTaO3 nano-photocatalyst was prepared and applied to degrade synthetic flotation reagent ammonium dibutyl dithiophosphate wastewater. Various characterization results confirmed the successful synthesis of NiO/La-NaTaO3, and UV-vis DRS analysis revealed a band gap of 3.96 eV for 4 wt% NiO/2.5% La-NaTaO3. Under UV light, the degradation rate of 20 mg 4 wt% NiO/2.5% La-NaTaO3 photocatalyst reached its optimum within 4.5 h at pH=3, exhibiting a 1.45 times improvement compared to pure NaTaO3. Radical trapping experiments and EPR results showed that ·OH and·O2- showed major contribution to the degradation. Furthermore, photocatalytic mechanisms and toxicity evolution were investigated, demonstrating the potential application of photocatalytic methods for treating flotation reagent wastewater.


Assuntos
Organotiofosfatos , Águas Residuárias , Raios Ultravioleta
2.
Front Psychiatry ; 11: 45, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32116859

RESUMO

Large-scale screening for depression has been using norms developed based on a given population at a given time. Researchers have attempted to adjust the cutoff scores over time and for different populations, but such efforts are too few and far in between to be sensitive to temporal and regional variations. In this study, we proposed an unsupervised machine learning approach to constructing depression classifications to overcome the limitations of the traditional norm-based method. Data were collected from 8,063 Chinese middle and high school students. Using k-means clustering, we generated four levels of depressive symptoms to match the norm-based classifications. We then evaluated the validity of the classifications by comparing them with the norm-based method (and its variations) in terms of their robustness, model performance (accuracy, AUC, and sensitivity), and convergent construct validity (i.e., associations with known correlates). The results showed that our automatic classification system performed well as compared to the norm-based method.

3.
Chemosphere ; 233: 327-335, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31176895

RESUMO

An amino-functionalized magnetic metal organic framework (MOF), Fe3O4-NH2@MIL-101(Cr), was employed for laccase immobilization for the first time. The immobilized laccase was synthesized by the adsorption and covalent binding method, thus exhibited high activity recovery, large immobilization capacity and good tolerance to low pH and high temperature conditions. The excellent stability enabled the immobilized laccase to retain 89% of its initial activity after storage for 28 days. When the ambient temperature reached 85 °C, the immobilized laccase showed 49.1% residual activity even after 6 h preservation. The stability of laccase in organic solvents such as methanol was also greatly improved. Application of the immobilized laccase for 2,4-dichlorophenol removal was also investigated. The adsorption by Fe3O4-NH2@MIL-101(Cr) contributed to a quick removal in the first hour, and the removal efficiency reached 87% eventually. When the reaction was completed, the immobilized laccase could be separated from the solution by a magnet. The results introduced a novel support for laccase immobilization, and the immobilized laccase had great potential in wastewater treatment.


Assuntos
Lacase/química , Estruturas Metalorgânicas/química , Fenóis/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Clorofenóis/química , Clorofenóis/isolamento & purificação , Estabilidade Enzimática , Enzimas Imobilizadas/química , Concentração de Íons de Hidrogênio , Magnetismo , Imãs , Metanol/química , Fenóis/química , Temperatura , Águas Residuárias , Poluentes Químicos da Água/química
4.
Biomed Pharmacother ; 108: 1357-1364, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30372838

RESUMO

BACKGROUND: Cardiac injury that induced by ischemia-reperfusion (I/R) significantly threatens human life, and autophagic cell death plays a pivotal role underlying it. Morphine Postconditioning (MpostC) has been identified to protect hearts against reperfusion injury, while whether MpostC treatment ameliorated cell autophage was still unclear. METHODS: The I/R rats were induced using left anterior descending artery occlusion followed by reperfusion. The H9C2 cells were hypoxia/reoxygenation (H/R) treated to mimic I/R in vitro. Luciferase reporter assay was performed to verify the relationship between miR-128 and HSP70, while RNA immunoprecipitation (RIP) and RNA pull-down were conducted to determine the interaction between UCA1 and miR-128. RESULTS: The expression of UCA1, miR-128 and HSP70 was decreased, increased and decreased, individually, in I/R cardiac tissues, while MpostC treatments significantly reversed it and also ameliorated infarct size and cell autophage. UCA1 regulated the expression of miR-128, while miR-128 regulated HSP70. MpostC alleviated cell autophage and tissue infarct as well as reversed the expression of UCA1, while miR-128 and HSP70 that induced by I/R caused cardiac injury and H/R. CONCLUSION: The present study indicated that MpostC protected against cardiac injury that induced by I/R through regulating UCA1/miR-128/HSP70.


Assuntos
Autofagia/efeitos dos fármacos , Morfina/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , RNA Longo não Codificante/fisiologia , Animais , Células Cultivadas , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/fisiologia , Masculino , MicroRNAs/fisiologia , Ratos , Ratos Sprague-Dawley , Regulação para Cima
5.
Sex Transm Dis ; 34(8): 592-7, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17325622

RESUMO

BACKGROUND: Little is known about risk of HIV and other STDs among men who have sex with men (MSM) in China. OBJECTIVE: To survey the prevalence and risk factors of HIV and syphilis and evaluate correlation of two infections among MSM in the Chinese capital city. METHODS: A community-based sample of 526 MSM was recruited in 2005 through Internet advertising, community outreach, and peer referring. Interviewer-administered interviews were conducted to collect information on demographics and sexual and other risk behaviors, and blood samples were collected to test for syphilis and HIV infections. RESULTS: Seventeen (3.2%) participants were HIV seropositive and 59 (11.2%) syphilis seropositive. Sixty-four percent of participants were migrants who did not have Beijing residence. Forty percent had >10 lifetime male sex partners and 28.8% reported having ever had sex with women. Consistent condom use with primary male sex partners ranged from 21% to 24%, with nonprimary male sex partners from 35% to 42%, and with female partners around 33%. Illicit drug use was not common; only 2.5% reported using Ecstasy or ketamine in the past 6 months. Multivariate logistic regression analyses demonstrated that >10 lifetime male sex partners were independently associated with seropositivity of both syphilis (OR, 1.9; 95% CI, 1.1-3.4) and HIV (OR, 4.3; 95% CI, 1.4-13.6). In addition, HIV infection is significantly associated with syphilis seropositivity (OR, 3.8; 95% CI, 1.3-10.8). CONCLUSIONS: High mobility, multiple sexual partners, and high prevalence of unprotected sex behaviors and syphilis infection suggest a potential rapid spread of HIV in Chinese MSM.


Assuntos
Infecções por HIV/epidemiologia , Homossexualidade Masculina , Assunção de Riscos , Sífilis/epidemiologia , Adolescente , Adulto , China/epidemiologia , Redes Comunitárias , Estudos Transversais , Infecções por HIV/sangue , Infecções por HIV/complicações , Infecções por HIV/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Sífilis/sangue , Sífilis/complicações , Sífilis/prevenção & controle , Saúde da População Urbana
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