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nZVI has attracted much attention in the remediation of contaminated soil and groundwater, but the application is limited due to its aggregation, poor stability, and weak migration performance. The biological CaCO3 was used as the carrier material to support nZVI and solved the nZVI agglomeration, which had the advantages of biological carbon fixation and green environmental protection. Meanwhile, the distribution of nZVI was characterised by SEM-EDS and TEM carefully. Subsequently, the dispersion stability of bare nZVI and CaCO3@nZVI composite was studied by the settlement experiment and Zeta potential. Sand column and elution experiments were conducted to study the migration performance of different materials in porous media, and the adhesion coefficient and maximum migration distances of different materials in sand columns were explored. SEM-EDS and TEM results showed that nZVI could be uniformly distributed on the surface of biological CaCO3. Compared with bare nZVI, CaCO3@nZVI composite suspension had better stability and higher absolute value of Zeta potential. The migration performance of nZVI was poor, while CaCO3@nZVI composite could penetrate the sand column and have good migration performance. What's more, the elution rates of bare nZVI and CaCO3@nZVI composite in quartz sand columns were 5.8% and 51.6%, and the maximum migration distances were 0.193 and 0.885 m, respectively. In summary, this paper studies the stability and migration performance of bare nZVI and CaCO3@nZVI composite, providing the experimental and theoretical support for the application of CaCO3@nZVI composite, which is conducive to promoting the development of green remediation functional materials.
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1,2,3-Trichloropropane (TCP) is an emerging groundwater pollutant, but there is a lack of reported studies on the abiotic natural attenuation of TCP by iron minerals. Furthermore, perturbation by O2 is common in the shallow subsurface by both natural and artificial processes. In this study, natural magnetite was selected as the reactive iron mineral to investigate its role in the degradation of TCP under O2 perturbation. The results indicated that the mineral structural Fe(II) on magnetite reacted with dissolved oxygen to generate O2-· and HO·. Both O2-· and HO· contributed to TCP degradation, with O2-· playing a more important role. After 56 days of reaction, 66.7% of TCP was completely dechlorinated. This study revealed that higher magnetite concentrations, smaller magnetite particle sizes, and lower initial TCP concentrations favored TCP degradation. The presence of <10 mg/L natural organic matter (NOM) did not affect TCP degradation. These findings significantly advance our understanding of the abiotic natural attenuation mechanisms facilitated by iron minerals under O2 perturbation, providing crucial insights for the study of natural attenuation.
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Óxido Ferrosoférrico , Oxígeno , Propano , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/química , Oxígeno/química , Óxido Ferrosoférrico/química , Propano/química , Propano/análogos & derivados , Agua Subterránea/química , Hierro/química , Biodegradación AmbientalRESUMEN
BACKGROUND: Restriction of food intake is a central pathological feature of anorexia nervosa (AN). Maladaptive eating behavior and, specifically, limited intake of calorie-dense foods are resistant to change and contribute to poor long-term outcomes. This study is a preliminary examination of whether change in food choices during inpatient treatment is related to longer-term clinical course. METHODS: Individuals with AN completed a computerized Food Choice Task at the beginning and end of inpatient treatment to determine changes in high-fat and self-controlled food choices. Linear regression and longitudinal analyses tested whether change in task behavior predicted short-term outcome (body mass index [BMI] at discharge) and longer-term outcome (BMI and eating disorder psychopathology). RESULTS: Among 88 patients with AN, BMI improved significantly with hospital treatment (p < 0.001), but Food Choice Task outcomes did not change significantly. Change in high-fat and self-controlled choices was not associated with BMI at discharge (r = 0.13, p = 0.22 and r = 0.10, p = 0.39, respectively). An increase in the proportion of high-fat foods selected (ß = 0.91, p = 0.02) and a decrease in the use of self-control (ß = -1.50, p = 0.001) predicted less decline in BMI over 3 years after discharge. CONCLUSIONS: Short-term treatment is associated with improvement in BMI but with no significant change, on average, in choices made in a task known to predict actual eating. However, the degree to which individuals increased high-fat choices during treatment and decreased the use of self-control over food choice were associated with reduced weight loss over the following 3 years, underscoring the need to focus on changing eating behavior in treatment of AN.
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Anorexia Nerviosa , Trastornos de Alimentación y de la Ingestión de Alimentos , Humanos , Anorexia Nerviosa/terapia , Anorexia Nerviosa/diagnóstico , Índice de Masa Corporal , Preferencias Alimentarias , Hospitalización , Resultado del TratamientoRESUMEN
COVID-19 pandemic has caused unprecedented negative impacts on our society, including further exposing inequity and disparity in public health. To study the impact of socioeconomic factors on COVID transmission, we first propose a spatial-temporal model to examine the socioeconomic heterogeneity and spatial correlation of COVID-19 transmission at the community level. Second, to assess the individual risk of severe COVID-19 outcomes after a positive diagnosis, we propose a dynamic, varying-coefficient model that integrates individual-level risk factors from electronic health records (EHRs) with community-level risk factors. The underlying neighborhood prevalence of infections (both symptomatic and pre-symptomatic) predicted from the previous spatial-temporal model is included in the individual risk assessment so as to better capture the background risk of virus exposure for each individual. We design a weighting scheme to mitigate multiple selection biases inherited in EHRs of COVID patients. We analyze COVID transmission data in New York City (NYC, the epicenter of the first surge in the United States) and EHRs from NYC hospitals, where time-varying effects of community risk factors and significant interactions between individual- and community-level risk factors are detected. By examining the socioeconomic disparity of infection risks and interaction among the risk factors, our methods can assist public health decision-making and facilitate better clinical management of COVID patients.
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Four polysaccharides, PTP-1, PTP-2, PTP-3 and PTP-4, were obtained from the water extraction of the stems of P. tricuspidata by anion exchange chromatography and gel filtration. The antioxidant activities of four PTPs were investigated, exhibiting different antioxidant activities, in which PTP-4 performed noticeable, with strong superoxide radical activity (comparable to BHT), high DPPH radical activity (78.53% at 1250⯵g/mL), moderate hydroxyl radical scavenging activity and reducing power activity. Furthermore, the chemical structure of PTP-4 was measured by FT-IR, GC, 1H and 13C NMR spectra, indicating its mainly composition of the arabinose, xylose, galactose, glucuronic acid, and mannose. Thus, the stems of P. tricuspidata could be used as a potential source for natural antioxidant.
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Antioxidantes/farmacología , Extractos Vegetales/farmacología , Tallos de la Planta/química , Polisacáridos/farmacología , Vitaceae/química , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Espectroscopía de Resonancia Magnética , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
In the present investigation, we carried a phytochemical study of an ethanol-soluble extract from the root barks of Aspidistra typica Baill., a traditional food and herb medicine, leading to the isolation of four different kinds of compounds, including one benzene substituted coumarin, two organic phosphonic compounds, and one xanthone. The novel benzene substituted coumarin typicacoumarin A (1) was a new type of coumarin, and the two new organic phosphonic compounds, typicalphosphine A (2) and typicalphosphine B (3) were isolated for the first time, and their structures were elucidated by spectral techniques, viz.1D, 2D NMR spectra and HR-ESI-MS. The xanthone compound typicaxanthone A (4) was discovered from nature for the first time. The two new organic phosphonic chlorides (2, 3) showed stronger antibacterial activities, which were comparable to berberine hydrochloride. And typicaxanthone A (4) showed much stronger antibacterial activity against Escherichia coli ATCC-25922 bacterial strain, while typicacoumarin A (1) showed moderate antibacterial activities, weaker than berberine hydrochloride.
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Antibacterianos/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Liliaceae/química , Antibacterianos/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Raíces de Plantas/química , Espectrometría de Masa por Ionización de ElectrosprayRESUMEN
A phytochemical study of the root barks of Aconitum sinchiangense W. T. Wang, a traditional Chinese herb medicine, led to the isolation of 15 diterpenoid alkaloids, including one new C19-diterpenoid alkaloid, sinchiangensine A (1), whose structure was determined by spectral methods including 2D NMR. Additionally, sinchiangensine A and its known analogue 3 were first reported as potential antitumor and antibacterial diterpenoid alkaloids, which showed significant antitumor activities against tumour cells (HL-60, A-549, SMCC-7721, MCF-7 and SW480), with IC50 comparable to cisplatin, and significant antibacterial activities against Staphylococcus aureus ATCC-25923 with MIC value of 0.147 and 0.144 µmol/mL, respectively.