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1.
Philos Trans A Math Phys Eng Sci ; 382(2271): 20230094, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38522461

ABSTRACT

At the Royal Society meeting in 2023, we have mainly presented our lunar orbit array concept called DSL, and also briefly introduced a concept of a lunar surface array, LARAF. As the DSL concept had been presented before, in this article, we introduce the LARAF. We propose to build an array in the far side of the Moon, with a master station which handles the data collection and processing, and 20 stations with maximum baseline of 10 km. Each station consists of 12 membrane antenna units, and the stations are connected to the master station by power line and optical fibre. The array will make interferometric observation in the 0.1-50 MHz band during the lunar night, powered by regenerated fuel cells. The whole array can be carried to the lunar surface with a heavy rocket mission, and deployed with a rover in eight months. Such an array would be an important step in the long-term development of lunar-based ultralong wavelength radio astronomy. It has a sufficiently high sensitivity to observe many radio sources in the sky, though still short of the dark age fluctuations. We discuss the possible options in the power supply, data communication, deployment etc. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades (part 2)'.

2.
Sci Total Environ ; 912: 169260, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38086481

ABSTRACT

It has been shown that exposure to nanoplastics (MNPs) through inhalation can induce pulmonary toxicity, but the toxicological mechanism of MNPs on the respiratory system remains unclear. Therefore, we explored the toxicological mechanism of exposure to polystyrene nanoplastics (PS-NPs) (0.05, 0.15, 0.2 mg/mL) on BEAS-2B cells. Results revealed that PS-NPs induce oxidative stress, increased apoptosis rate measured by flow cytometry, the key ferroptosis protein (GPX4 and FTH1) reduction, increased iron content, mitochondrial alterations, and increased malondialdehyde (MDA) level. Besides, consistent results were observed in mice exposed to PS-NPs (5 mg/kg/2d, 10 mg/kg/2d). Thus, we proved that PS-NPs induced cell death and lung damage through apoptosis and ferroptosis. In terms of mechanism, the elevation of the endoplasmic reticulum (ER) stress protein expression (IRE1α, PERK, XBP1S, and CHOP) revealed that PS-NPs induce lung damage by activating the two main ER stress pathways. Furthermore, the toxicological effects of PS-NPs observed in this study are attenuated by the ROS inhibitor N-acetylcysteine (NAC). Collectively, NPs-induced apoptosis and ferroptosis are attenuated by NAC via inhibiting the ROS-dependent ER stress in vitro and in vivo. This improves our understanding of the mechanism by which PS-NPs exposure leads to pulmonary injury and the potential protective effects of NAC.


Subject(s)
Ferroptosis , Microplastics , Mice , Animals , Reactive Oxygen Species/metabolism , Polystyrenes/toxicity , Endoplasmic Reticulum Chaperone BiP , Endoribonucleases/pharmacology , Protein Serine-Threonine Kinases , Lung/metabolism , Acetylcysteine/pharmacology , Apoptosis , Endoplasmic Reticulum Stress
3.
Environ Toxicol ; 38(9): 2219-2227, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37300869

ABSTRACT

Cadmium (Cd) is a hypertoxic heavy metal that may be exposed to environmental pollutants by humans and animals. It can lead to cognitive disfunction, and is linked to neurodegenerative diseases. Cadmium reportedly can induce endoplasmic reticulum (ER) stress, but few studies have concentrated on it in nerve cells, and the connection between ER stress and neuroinflammation. In this study, in vitro experiments on SH-SY5Y neuroblastoma cells were carried out. We aimed at exploring whether Cd attributed to the cell pyroptosis and the role of PERK in promoting this form of cell damage which can induce strong inflammatory responses. Our results demonstrated that CdCl2 treatment induced excess reactive oxygen species (ROS) production, caused significant modifications in the expression of PERK and increased TXNIP, NLRP3, IL-1ß, IL-18, and caspase1 in SH-SY5Y cells. In addition, scavenging ROS with N-acetylcysteine or inhibiting the expression of PERK by using GSK2606414, rescued the SH-SY5Y cells from cadmium-induced pyroptosis. In conclusion, the results suggest that Cd induces pyroptotic death of SH-SY5Y cells through ER stress, and this may be the potential mechanism of Cd incurring neurological diseases.


Subject(s)
Neuroblastoma , Pyroptosis , Animals , Humans , Cadmium/toxicity , Cadmium/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Reactive Oxygen Species/metabolism , Cell Line, Tumor , Endoplasmic Reticulum Stress , Carrier Proteins
4.
BMC Neurol ; 22(1): 326, 2022 Aug 31.
Article in English | MEDLINE | ID: mdl-36045323

ABSTRACT

BACKGROUND: To determine the association between dynamic neutrophil-to-lymphocyte ratio (NLR) during hospitalization and mortality 1 month after ischemia reperfusion in patients undergoing endovascular treatment (EVT) with successful revascularization for acute large vessel occlusion stroke. METHODS: This retrospective study included patients who had undergone successful EVT. Information was collected regarding patients' clinical characteristics, imaging data, and mortality at 1 month. Univariate and multivariate logistic regression models were applied to assess the association between NLR and mortality. We used a generalized additive model and a generalized additive mixed model to compare trends in NLR over time between survivors and nonsurvivors. RESULTS: A total of 237 patients were included. During the 1-month follow-up, 42 of these patients (17.7%) died. The multivariate analysis demonstrated that NLR obtained within 12 to 24 hours (odds ratio [OR] = 1.18; 95% confidence interval [CI]: 1.04, 1.33; P = 0.008), 24 to 48 hours (OR = 1.16; 95% CI: 1.01, 1.35; P = 0.044), and 48 to 72 hours (OR = 1.23; 95% CI: 1.03, 1.47; P = 0.021) after EVT were independently associated with mortality at 1 month. In addition, there was a trend for NLR to decrease gradually over time for both survivors and nonsurvivors; however, NLR in survivors decreased by an average of 0.29 daily than in nonsurvivors. CONCLUSIONS: Increased NLR in the early period after EVT was associated with an increased risk of mortality, and a continued trend toward higher NLR over time was also linked with a higher mortality risk.


Subject(s)
Brain Ischemia , Ischemic Stroke , Stroke , Brain Ischemia/complications , Humans , Lymphocytes , Neutrophils , Retrospective Studies , Stroke/complications , Treatment Outcome
5.
Materials (Basel) ; 14(1)2020 Dec 31.
Article in English | MEDLINE | ID: mdl-33396193

ABSTRACT

Having higher capacity to undertake pressures and larger compensation ability compared with the U-shape bellows, toroidal or Ω-shape bellows are being more and more widely used in engineering. The wave-shape and wall thickness reduction of bellows are the most important parameters for measuring the hydroforming quality of the bellows. In order to provide references for actual manufacturing, it is valuable to study the factors influencing the hydroforming process and quality of the bellows. In this paper, finite element simulations of the hydroforming process of a monolayer and single-wave toroidal bellows and a two-layer and four-wave toroidal bellows were carried out. Stress and strain distributions before and after unloading were analyzed and the wave height and wall thickness reduction were examined. The numerical results were verified by the actual hydroforming measurements. In addition, ranges of the significant structural or operating factors for producing better bellows were studied and a formula to compute the wall thickness reduction was fitted based on the sufficient numerical results of the hydroforming simulations.

6.
Wei Sheng Yan Jiu ; 45(6): 957-962, 2016 Nov.
Article in Chinese | MEDLINE | ID: mdl-29903080

ABSTRACT

OBJECTIVE: To establish a method for determination of 16 polycyclic aromatic hydrocarbons( PAHs) in edible oils by gas chromatography-mass spectrometry( GC/MS) combined with molecularly imprinted solid phase extraction( MISPE-GC/MS). METHODS: Oil samples were diluted with n-hexane, purified by SPE cartridges based on molecularly imprinted polymer. The cartridges were washed by n-hexane to remove impurities, then eluted with dichloromethane. After being concentrated to a volume of 200µL, the analytes were separated by capillary column( 30 m×0. 25 mm×0. 25 µm) and analyzed by GC/MS with selected ion monitoring( SIM) mode. Isotope internal standard method was adopted for quantification. RESULTS: The 16 kinds of PAHs showed good linearity in the range of 2-20 µg/L( r > 0. 998). The detection limits ranged from 0. 1 to0. 6 µg/kg. The recoveries of spiked samples at the level of 2 µg/kg and 10 µg/kg were in the range of 75. 5%-125. 2%( n = 6), the relative standard deviations( RSD) were all less than 15%. CONCLUSION: The proposed method is selective, fast, and presentsexcellent purification effect as well as high sensitivity, which makes it capable for rapid determination of 16 PAHs in edible oils with satisfactory accuracy.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Oils/chemistry , Polycyclic Aromatic Hydrocarbons/analysis , Solid Phase Extraction/methods , Humans , Limit of Detection
7.
Article in English | MEDLINE | ID: mdl-25871070

ABSTRACT

We investigate the completely packed O(n) loop model on the square lattice, and its generalization to an Eulerian graph model, which follows by including cubic vertices which connect the four incoming loop segments. This model includes crossing bonds as well. Our study was inspired by existing exact solutions of the so-called coloring model due to Schultz and Perk [Phys. Rev. Lett. 46, 629 (1981)], which is shown to be equivalent with our generalized loop model. We explore the physical properties and the phase diagram of this model by means of transfer-matrix calculations and finite-size scaling. The exact results, which include seven one-dimensional branches in the parameter space of our generalized loop model, are compared to our numerical results. The results for the phase behavior also extend to parts of the parameter space beyond the exactly solved subspaces. One of the exactly solved branches describes the case of nonintersecting loops and was already known to correspond with the ordering transition of the Potts model. Another exactly solved branch, describing a model with nonintersecting loops and cubic vertices, corresponds with a first-order, Ising-like phase transition for n>2. For 12 this branch is the locus of a first-order phase boundary between a phase with a hard-square, lattice-gas-like ordering and a phase dominated by cubic vertices. A mean-field argument explains the first-order nature of this transition.

8.
J Chromatogr Sci ; 53(2): 210-8, 2015 Feb.
Article in English | MEDLINE | ID: mdl-24850700

ABSTRACT

A novel and effective dispersive micro-solid-phase extraction (d-µ-SPE) using ethanediamine-functionalized magnetic Fe3O4 polymer (EDA-MP) as an efficient adsorbent in wine sample was developed. Based on this, a simple and time-saving analytical method for the simultaneous determination of seven synthetic colorants (i.e., tartrazine, amaranth, carmine, sunset yellow, allura red, brilliant blue and erythrosine) in wine by reversed-phase high-performance liquid chromatography with an ultraviolet detector was established. The experimental parameters, including the chromatographic retention behavior of studied synthetic colorants, the effect of the usage amount of cross-linking monomer, the effect of the usage amount of EDA-MP on the recovery and the recyclability of the adsorbents, were studied in detail. The results showed that the EDA-MP could be reused efficiently at least six times. Under optimized conditions, the recoveries for all analytes were in the range of 88.6-105.2%, with the intraday relative standard deviations (RSDs) ranging from 2.1 to 8.2% and the interday RSDs ranging from 3.4 to 8.7%, and all the analytes had good linearities in the tested ranges with correlation coefficients (r(2)) >0.9995. The limits of quantification for seven synthetic colorants were between 0.12 and 0.45 mg L(-1). The developed method was successfully applied to wine samples, and it was confirmed that the EDA-MP particles were highly effective d-µ-SPE materials.


Subject(s)
Chromatography, Reverse-Phase/methods , Food Coloring Agents/analysis , Solid Phase Microextraction/methods , Wine/analysis , Adsorption , Ethylenediamines/chemistry , Ferrosoferric Oxide/chemistry , Limit of Detection , Linear Models , Reproducibility of Results
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