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1.
Environ Sci Technol ; 54(20): 12979-12988, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32966052

RESUMO

A new technique involving large-volume (10 m3) samples of seawater was used to determine the abundance of microplastics (MPs) in the water column in the West Pacific Ocean and the East Indian Ocean. Compared to the conventional sampling methods based on smaller volumes of water, the new data yielded abundance values for the deep-water column that were at least 1-2 orders of magnitude lower. The data suggested that limited bulk volumes currently used for surface sampling are insufficient to obtain accurate estimates of MP abundance in deep water. Size distribution data indicated that the lateral movement of MPs into the water column contributed to their movement from the surface to the bottom. This study provides a reliable dataset for the water column to enable a better understanding of the transport and fate of plastic contamination in the deep-ocean ecosystem.


Assuntos
Microplásticos , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Oceano Índico , Oceano Pacífico , Plásticos , Poluentes Químicos da Água/análise
2.
ACS Omega ; 8(48): 46091-46100, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38075745

RESUMO

Recently, colloidal gas aphron (CGA) drilling fluids have successfully solved the problem of drilling low-pressure depleted oil and gas reservoirs. However, with the increase in the drilling depth and the development of geothermal resources, high-temperature stable CGA drilling fluids need to be developed urgently. This research reports a highly stable nano-SiO2-based CGA system with a temperature resistance of 200 °C. Waring-Blender tests show that 1.5-3% nano-SiO2 greatly improves the high-temperature stability of the CGA system, and the half-life of foam aged at 120-200 °C can reach 6-12 h. Also, the nano-SiO2-based CGA system aged at 200 °C can maintain an independent and stable morphology during the observation period (60 min), and there is no obvious drainage and merger in the system. The stabilizing mechanism of nano-SiO2 has been revealed, which can be summarized as the comprehensive effect of adsorption, viscosity increase, and cross-linking. In other words, the addition of nano-SiO2 enhanced steric hindrance and liquid film strength by reducing the surface tension, increasing fluid viscosity, and forming a network-like structure.

3.
Foods ; 12(17)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37685220

RESUMO

Three-dimensional printing is one of the most precise manufacturing technologies with a wide variety of applications. Three-dimensional food printing offers potential benefits for food production in terms of modifying texture, personalized nutrition, and adaptation to specific consumers' needs, among others. It could enable innovative and complex foods to be presented attractively, create uniquely textured foods tailored to patients with dysphagia, and support sustainability by reducing waste, utilizing by-products, and incorporating eco-friendly ingredients. Notable applications to date include, but are not limited to, printing novel shapes and complex geometries from candy, chocolate, or pasta, and bio-printed meats. The main challenges of 3D printing include nutritional quality and manufacturing issues. Currently, little research has explored the impact of 3D food printing on nutrient density, bioaccessibility/bioavailability, and the impact of matrix integrity loss on diet quality. The technology also faces challenges such as consumer acceptability, food safety and regulatory concerns. Possible adverse health effects due to overconsumption or the ultra-processed nature of 3D printed foods are major potential pitfalls. This review describes the state-of-the-art of 3D food printing technology from a nutritional perspective, highlighting potential applications and current limitations of this technology, and discusses the potential nutritional risks and benefits of 3D food printing.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36673924

RESUMO

It is important to investigate how to achieve carbon unlocking in the transport sector, especially in transport infrastructure, in order to contribute to the achievement of carbon neutrality targets and the 2030 Sustainable Development Goals. This study aims to investigate the necessary and sufficient conditions to achieve carbon unlocking in transport infrastructure. To achieve this, a combination of partial least squares structural equation modeling (PLS-SEM) and necessary condition analysis (NCA) methods have been used to examine whether there are unidentified necessity factors beyond the currently recognized 'technology-in-institution' (TIC) lock-in. This study also explores how the carbon unlocking of transport infrastructure can be achieved through the unlocking of relevant factors. The study includes 366 points from a subjective questionnaire from the government, transport infrastructure researchers, and relevant businesspeople. We found that, at the adequacy level, achieving institutional and technological unlocking is sufficient and economic factors have little impact on transport infrastructure (0.06), and that institutional and technical factors have a large impact on carbon unlocking (0.453, 0.280); however, from the necessary point of view, carbon unlocking at the economic level is necessary to achieve the goal of a medium to high level of carbon unlocking. To achieve carbon unlocking at this level (over 50%), a combination of technological, institutional, and economic factors is required. To achieve full carbon unlocking, the technology, system, and economy need to be at least 0.533, 0.791, and 0.63 unlocked. Therefore, we can conclude that by using the joint analysis of PLS-SEM and NCA, we have achieved an extension of the traditional TIC and identified sufficient and necessary conditions to achieve a medium to high degree of carbon unlocking.


Assuntos
Carbono , Desenvolvimento Sustentável , Análise dos Mínimos Quadrados , Análise de Classes Latentes , Tecnologia
5.
ACS Omega ; 7(43): 38380-38388, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36340081

RESUMO

Drilling fluid lubricants guarantee safe and fast drilling. When drilling high-temperature or NaCl/CaCl2-containing formations, there is an urgent need to develop environmentally friendly lubricants that are resistant to high temperature and ionic contamination. In this study, a deep eutectic solvent (DES) ChCl-PEG lubricant for a water-based drilling fluid was designed and prepared. ChCl-PEG is a kind of biodegradable material with high thermal stability formed by hydrogen bonding between choline chloride (ChCl) and polyethylene glycol (PEG). Within 240 °C, ChCl-PEG significantly improved the lubricating properties of drilling fluids and mud cakes. The lubrication coefficient (K) was controlled within 0.2, and the reduction rate of the adhesion coefficient (Δf) was higher than 40%. The salt and calcium resistances of ChCl-PEG at high temperature (150 °C) are as high as 36% NaCl and 20% CaCl2. Under these conditions, ChCl-PEG maintains a low value of K: 0.097-0.157 (5-36% NaCl) and 0.145-0.162 (5-20% CaCl2), respectively. Also, it maintains higher values of Δf, which can reach up to 51.6% and 80%. The lubricating mechanism of ChCl-PEG can be summarized as the adsorption of ChCl and the formation of a large number of hydrated molecules.

6.
PLoS One ; 17(9): e0274002, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36099271

RESUMO

The impact of collusion during the bidding processes of Chinese government investment projects is a major concern in academic and policy circles, as collusion breeds corruption and destroys the credibility of governments. Furthermore, it negatively impacts successful project completion, leading to cost overruns and the illegitimate enrichment of colluding agents, regardless of the intended social benefits. Using data from 166 selected regional policy implementations as the research sample, this paper uses the fuzzy set qualitative comparative analysis method to conduct a group analysis of typical cases. The purpose of this study is to identify and better understand the cooperative regional policy implementation environments in China and to identify effective methods to improve the governance quality of collusion controls in construction investment project bidding processes. Five key control paths are identified, covering 94% of the cases. It is also found that in lower social collusion situations, reasonable market competition regulations can directly reduce collusive behavior. The research results will help the government to formulate more adaptive control policies and promote high-quality development of government investment projects.


Assuntos
Governo , Investimentos em Saúde , China
7.
Comput Intell Neurosci ; 2022: 2897672, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35875775

RESUMO

To effectively diagnose and monitor the vertical collusion in construction project bidding, this paper developed a comprehensive evaluation model with deep neural network and transfer learning. By this model, the collusion characteristics of bidders, tenderers, and bid evaluation experts were mined from limited data set hidden and collusion tendency was evaluated. Firstly, 18 evaluation indicators were established from literature review, court file summarization, typical case analysis, and expert consultation. Then, a comprehensive evaluation model was developed with the deep neural network and transfer learning. Finally, the model was trained and tested with the collected data set. The test results showed that the developed model achieved 87.3% identification accuracy in collusion tendency evaluation of different subjects.


Assuntos
Aprendizado Profundo , Humanos , Aprendizagem , Redes Neurais de Computação
8.
ACS Omega ; 6(37): 23788-23801, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34568659

RESUMO

Xanthan gum (XG) was widely used as an oilfield chemical treatment agent because of its environmental protection and diverse functions. With the increased drilling depth and formation complexity, the shortcomings such as poor solubility and low resistance to temperature were gradually exposed. In this study, a modified XG derivative XG-g-AAA was synthesized by grafting XG with acrylic acid (AA), acrylamide (AM), and 2-acrylamido-2-methylpropane sulfonic acid (AMPS). The chemical structure of XG-g-AAA was determined by Fourier transform infrared spectroscopy and nuclear magnetic resonance (1H NMR). Then, the solubility, high-temperature rheology and filtration properties, resistance to Na+/Ca2+, and compatibility were investigated. Results show that (1) both in aqueous and salt solutions, XG-g-AAA can completely be dissolved within 15 min. The significant improvement of the solubility of XG-g-AAA makes it more suitable for field use. (2) XG-g-AAA is less sensitive to high temperatures, and the viscosity decay decreased by 23.3 and 21.3% than XG at 150 and 180 °C, respectively. XG-g-AAA-based drilling fluid is a high-quality drilling fluid with significant shear thinning behavior, and the power-law model is the optimal model to describe its high-temperature rheology. Within 150 °C, 1.5% XG-g-AAA can maintain a reasonable value of the flow behavior index (n) (0.55-0.69), filtration volume (<11.6 mL), and sufficient gel strength (GS). At 150-200 °C, 3% XG-g-AAA is recommended. The value of n was in the range of 0.45-0.62, and the fluid loss was within 10 mL. However, 3% XG-g-AAA cannot provide enough GS at 200 °C; thus, a shear strength-improving agent is recommended to be added. (3) XG-g-AAA showed excellent contamination tolerance and compatibility. It could resist 2 wt % CaCl2 and 35 wt % NaCl at room temperature and 0.75% CaCl2 and 5% NaCl after 150 °C aging. (4) XG-g-AAA showed compatibility with sulfonated drilling fluids and could replace commercial fluid loss agents in the formula. Furthermore, the high-temperature fluid loss control mechanism was discussed by analyzing the effects of XG-g-AAA on the bentonite layer spacing, particle size distribution, stability of the colloidal system, and mud cakes.

9.
Stem Cell Res Ther ; 12(1): 462, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34407865

RESUMO

BACKGROUND: The dual inhibitors of receptor interacting protein kinase-1 and -3 (RIP1 and RIP3) play an important role in cell death processes and inflammatory responses. White matter injury (WMI), a leading cause of neurodevelopmental disabilities in preterm infants, which is characterized by extensive myelination disturbances and demyelination. Neuroinflammation, leads to the loss and differentiation-inhibition of oligodendrocyte precursor cells (OPCs), represents a major barrier to myelin repair. Whether the novel RIP1/RIP3 dual inhibitor ZJU-37 can promote transplanted OPCs derived from human neural stem cells (hOPCs) survival, differentiation and myelination remains unclear. In this study, we investigated the effect of ZJU-37 on myelination and neurobehavioral function in a neonatal rat WMI model induced by hypoxia and ischemia. METHODS: In vivo, P3 rat pups were subjected to right common carotid artery ligation and hypoxia, and then treated with ZJU-37 or/and hOPCs, then OPCs apoptosis, myelination, glial cell and NLRP3 inflammasome activation together with cognitive outcome were evaluated at 12 weeks after transplantation. In vitro, the effect of ZJU-37 on NLRP3 inflammasome activation in astrocytes induced by oxygen-glucose deprivation (OGD) were examined by western blot and immunofluorescence. The effect of ZJU-37 on OPCs apoptosis induced by the conditioned medium from OGD-injured astrocytes (OGD-astrocyte-CM) was analyzed by flow cytometry and immunofluorescence. RESULTS: ZJU-37 combined with hOPCs more effectively decreased OPC apoptosis, promoted myelination in the corpus callosum and improved behavioral function compared to ZJU-37 or hOPCs treatment. In addition, the activation of glial cells and NLRP3 inflammasome was reduced by ZJU-37 or/and hOPCs treatment in the neonatal rat WMI model. In vitro, it was also confirmed that ZJU-37 can suppress NLRP3 inflammasome activation in astrocytes induced by OGD. Not only that, the OGD-astrocyte-CM treated with ZJU-37 obviously attenuated OPC apoptosis and dysdifferentiation caused by the OGD-astrocyte-CM. CONCLUSIONS: The novel RIP1/RIP3 dual inhibitor ZJU-37 may promote OPC survival, differentiation and myelination by inhibiting NLRP3 inflammasome activation in a neonatal rat model of WMI with hOPC graft.


Assuntos
Lesões Encefálicas , Substância Branca , Animais , Astrócitos , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Bainha de Mielina , Oligodendroglia , Ratos
10.
J Pediatr Endocrinol Metab ; 33(4): 487-493, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32069235

RESUMO

Background Elevated serum uric acid concentrations have been associated with metabolic syndrome. However, only limited information is available on the prevalence of hyperuricaemia in adolescents. Therefore, the aim of our cross-sectional study was to study the prevalence of hyperuricaemia and dietary patterns in adolescents aged 13-16 years living in Yangzhou, China. Methods Adolescents were asked to complete a 20-item food frequency questionnaire (FFQ) and provide an overnight fasting finger-prick sample. Principal component analysis (PCA) with varimax rotation was used to derive the dietary patterns that might be associated with high uric acid concentrations. Results A total of 1070 adolescents were recruited. Of these, 53.6% (n = 574) were females, and 58.5% (n = 625) were within the normal body mass index (BMI) range. The males had a significantly higher serving size and frequency in their weekly food consumption, including meat, poultry, Chinese cereal staple foods and Western-style fast foods, than the females (all p < 0.02). The overall mean serum uric acid concentration and prevalence of hyperuricaemia were 368.6 ± 114.5 µmol/L and 37.9%, respectively. The prevalence of hyperuricaemia was 4.633 times greater among the participants who were overweight and obese than among those who were underweight. On the other hand, the prevalence of hyperuricaemia was 0.694 times lower among the participants who had normal weight than those who were underweight. Conclusions The prevalence of hyperuricaemia was relatively high in Chinese adolescents. The prevention of hyperuricaemia measures should be strengthened in adolescents to effectively control for obesity and gout, which tend to persist into adulthood.


Assuntos
Dieta/efeitos adversos , Hiperuricemia/epidemiologia , Síndrome Metabólica/fisiopatologia , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Ácido Úrico/sangue , Adolescente , Criança , China/epidemiologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Hiperuricemia/sangue , Hiperuricemia/etiologia , Masculino , Prevalência , Prognóstico , Fatores de Risco
11.
Exp Ther Med ; 5(2): 499-502, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23403492

RESUMO

The present study aimed to assess the value of endoscopic jejunostomy for post-biliary intestinal anastomosis biliary complications. The clinical data of the endoscopic therapies by jejunal approach for post-biliary intestinal anastomosis biliary complications in 13 patients (16 surgeries in total) were retrospectively analyzed. The surgical success rate was 100% (16/16). Nasobiliary tube detention was performed for 2 patients, plastic stent placement for 5 and biliary metal stent placement for 4. The remaining two patients did not retain any drainage tube or bracket after surgery. The incidence rate of intraoperative anastomotic stenostomia was 76.9% (10/13). A noticeable postoperative decrease in bilirubin levels was observed in 10 patients. The level of gallstone-free patients was 75% (3/4). There were 10 cases in which cholangitis remission or no attack was identified. Post-operative incisional infection occurred in 3 patients, hepatophyma in 1 and an intestinal fistula in 1. Endoscopic therapy by jejunal approach for post-biliary intestinal anastomosis biliary complications has the virtue of being safe, effective and minimally invasive. It has extensive potential applications in clinical practice.

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