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1.
Environ Sci Technol ; 58(29): 13056-13064, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38900493

RESUMEN

Rubber-derived chemicals (RDCs) originating from tire and road wear particles are transported into road stormwater runoff, potentially threatening organisms in receiving watersheds. However, there is a lack of knowledge on time variation of novel RDCs in runoff, limiting initial rainwater treatment and subsequent rainwater resource utilization. In this study, we investigated the levels and time-concentration profiles of 35 target RDCs in road stormwater runoff from eight functional areas in the Greater Bay Area, South China. The results showed that the total concentrations of RDCs were the highest on the expressway compared with other seven functional areas. N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), 6PPD-quinone, benzothiazole, and 1,3-diphenylguanidine were the top four highlighted RDCs (ND-228840 ng/L). Seasonal and spatial differences revealed higher RDC concentrations in the dry season as well as in less-developed regions. A lag effect of reaching RDC peak concentrations in road stormwater runoff was revealed, with a lag time of 10-90 min on expressways. Small-intensity rainfall triggers greater contamination of rubber-derived chemicals in road stormwater runoff. Environmental risk assessment indicated that 35% of the RDCs posed a high risk, especially PPD-quinones (risk quotient up to 2663). Our findings contribute to a better understanding of managing road stormwater runoff for RDC pollution.


Asunto(s)
Lluvia , Goma , Ciudades , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , China
2.
J Environ Manage ; 348: 119312, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37857214

RESUMEN

Metal oxides play a promising role in the transformation of polyphenols and amino acids involved in naturally occurring humification. The objective of this study was to explore the synergistic interactions between Fe2O3 and O2 in the formation of humic substances under a controlled O2 atmosphere (0%, 21% and 40% O2 levels). The results indicate that an O2 level of 21% with Fe2O3 was optimal for humic acid (HA) production. Hydroxyl radicals (∙OH) formed and promoted the formation of HA in the presence of O2, and O2 improved the enhancing capacity of Fe2O3 by oxidizing Fe(II) to Fe(III). Moreover, the combination of these processes resulted in a synergistic improvement in humification. The evolution of functional groups in HA suggested that O2 promoted the formation of oxygen-containing groups such as lipids, and Fe2O3 was conducive to the formation of dark-coloured polymers during the darkening process of humification. Furthermore, the O2 level of 40% inhibited the formation of HA by reducing the transformation from Fe(III) to Fe(II). The XRD results showed few changes in the composition of Fe2O3 before and after humification, which indicated that Fe2O3 was a catalyst and an oxidant. The heterospectral UV-Vis/FTIR results suggested that ∙OH attacked phenolic rings to form the aromatic ring skeleton of HA and benefit the ring-opening copolymerization of humic precursors. In addition, structural equation modelling demonstrated that dissolved Fe was the key parameter affecting the HA yield. These findings provide new insights into the synergism of O2-mediated ∙OH production associated with metal oxide-facilitated humification.


Asunto(s)
Sustancias Húmicas , Oxígeno , Sustancias Húmicas/análisis , Especies Reactivas de Oxígeno , Radical Hidroxilo , Compuestos Férricos/química , Fenoles , Óxidos , Compuestos Ferrosos
3.
Bioresour Technol ; 393: 130120, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38029803

RESUMEN

Phenol-rich wine grape pomace (WGP) improves the conversion of pig manure (PM) into humic acid (HA) during composting. However, the impact of using combinations of Fe2O3 and biochar known to promote compost maturation remains uncertain. This research explored the individual and combined influence of biochar and Fe2O3 during the co-composting of PM and WGP. The findings revealed that Fe2O3 boosts microbial network symbiosis (3233 links), augments the HA yield to 3.38 by promoting polysaccharide C-O stretching, and improves the germination index to 124.82 %. Limited microbial interactions, increased by biochar, resulted in a lower HA yield (2.50). However, the combination weakened the stretching of aromatics and quinones, which contribute to the formation of HA, resulting in reduced the humification to 2.73. In addition, Bacillus and Actinomadura were identified as pivotal factors affecting HA content. This study highlights Fe2O3 and biochar's roles in phenol-rich compost humification, but combined use reduces efficacy.


Asunto(s)
Carbón Orgánico , Compostaje , Vitis , Animales , Porcinos , Suelo , Estiércol , Sustancias Húmicas/análisis , Fenoles , Interacciones Microbianas , Fenol
4.
Medicine (Baltimore) ; 103(4): e36886, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38277566

RESUMEN

INTRODUCTION: Hepatic artery-portal vein malformation is rarely encountered in clinical practice. Here, we reported a case of liver cirrhosis combined with hepatic artery-portal vein malformation with refractory ascites as the main symptom. And it was successfully treated by us. The present case demonstrates the role of hepatic artery-portal vein malformation in cirrhotic ascites and the importance of early diagnosis and interventional treatment. This article may provides some experience for the treatment of such patients. PATIENT CONCERNS: The patient was a 72-year-old woman with a 40-year history of Hepatitis B virus surface antigen positivity who sought medical advice with a chief complaint of abdominal distension for 1 week. DIAGNOSES: Enhanced abdominal computed tomography imaging of this patient revealed liver cirrhosis, splenomegaly, esophageal and gastric varices, massive ascites, and a low-density area in the S4 segment of the liver with an ambiguous boundary. Widening of the left branch of the portal vein was evident, and the portal vein was highlighted in the arterial phase and the venous phase. Digital subtraction angiography revealed substantial thickening of the left hepatic artery, and the administered contrast agent drained through the malformed vascular mass to the thickened left portal vein. Liver cirrhosis combined with hepatic artery-portal vein malformation were diagnosed. And we considered that the artery-portal vein malformation in this patient might be caused by cirrhosis. INTERVENTIONS: The patient was applied diuretics, entecavir and transcatheter embolization. OUTCOMES: The patient ascites did not resolve significantly when treated with diuretics alone. After the transcatheter embolization, the patient ascites relieved remarkably. CONCLUSION: The patient underwent transcatheter embolization for hepatic artery-portal vein malformation, after which her ascites resolved with good short-term curative efficacy. So, the patients who suffered from liver cirrhosis combined with hepatic artery-portal vein malformation and refractory ascites, should be active on transcatheter embolization.


Asunto(s)
Arteria Hepática , Vena Porta , Humanos , Femenino , Anciano , Vena Porta/diagnóstico por imagen , Vena Porta/patología , Arteria Hepática/diagnóstico por imagen , Ascitis/etiología , Ascitis/terapia , Ascitis/diagnóstico , Cirrosis Hepática/complicaciones , Cirrosis Hepática/patología , Diuréticos
5.
Phys Rev E ; 107(5-2): 055211, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37328975

RESUMEN

Equilibrium molecular dynamics simulations are performed to study two-dimensional (2D) dusty plasma liquids. Based on the stochastic thermal motion of simulated particles, the longitudinal and transverse phonon spectra are calculated, and used to determine the corresponding dispersion relations. From there, the longitudinal and transverse sound speeds of 2D dusty plasma liquids are obtained. It is discovered that, for wavenumbers beyond the hydrodynamic regime, the longitudinal sound speed of a 2D dusty plasma liquid exceeds its adiabatic value, i.e., the so-called fast sound. This phenomenon appears at roughly the same length scale of the cutoff wavenumber for transverse waves, confirming its relation to the emergent solidity of liquids in the nonhydrodynamic regime. Using the thermodynamic and transport coefficients extracted from the previous studies, and relying on the Frenkel theory, the ratio of the longitudinal to the adiabatic sound speeds is derived analytically, providing the optimal conditions for fast sound, which are in quantitative agreement with the current simulation results.


Asunto(s)
Polvo , Sonido , Simulación de Dinámica Molecular , Termodinámica , Movimiento (Física)
6.
Micromachines (Basel) ; 13(12)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36557373

RESUMEN

The memristor-based neural network configuration is a promising approach to realizing artificial neural networks (ANNs) at the hardware level. The memristors can effectively simulate the strength of synaptic connections between neurons in neural networks due to their diverse significant characteristics such as nonvolatility, nanoscale dimensions, and variable conductance. This work presents a new synaptic circuit based on memristors and Complementary Metal Oxide Semiconductor(CMOS), which can realize the adjustment of positive, negative, and zero synaptic weights using only one control signal. The relationship between synaptic weights and the duration of control signals is also explained in detail. Accordingly, Widrow-Hoff algorithm-based memristive neural network (MNN) circuits are proposed to solve the recognition of three types of character pictures. The functionality of the proposed configurations is verified using SPICE simulation.

7.
Folia Neuropathol ; 60(1): 92-104, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35359149

RESUMEN

Traumatic brain injury (TBI) is a severe condition that leads to brain damage and affects brain function. Importantly, TBI incurs public health costs due to its high mortality, and effective treatment for TBI is still lacking. Docosahexaenoic acid (DHA) has a neuroprotective effect that can reduce oxidative, apoptosis, and inflammatory processes. Administration of DHA after TBI attenuates oxidative stress and protein accumulation and is regarded as a potential therapeutic. Iduna is a regulator of parthanatos, and upregulation of Iduna reduces cellular damage and mitochondrial dysfunction. Thus, we speculated that overexpression of Iduna might promote DHA therapy in the treatment of TBI. Here, we found that after combination overexpression of Iduna and DHA in a mouse model of TBI, the expression of inflammatory factors was reduced, while the secretion of neuroprotective factors was increased. In addition, we found that these effects might be mediated by the Wnt/MDM2 pathway, and Iduna might be a therapeutic target for TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Fármacos Neuroprotectores , Animales , Apoptosis , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Modelos Animales de Enfermedad , Ácidos Docosahexaenoicos/farmacología , Ratones , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico
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