Neutron Energy Spectrum Measurements with a Compact Liquid Scintillation Detector on EAST

A neutron detector based on EJ301 liquid scintillator has been employed at EAST to measure the neutron energy spectrum for D-D fusion plasma. The detector was carefully characterized in different quasi-monoenergetic neutron fields generated by a 4.5 MV Van de Graaff accelerator. In recent experimental campaigns, due to the low neutron yield at EAST, a new shielding device was designed and located as close as possible to the tokamak to enhance the count rate of the spectrometer. The fluence of neutrons and gamma-rays was measured with the liquid neutron spectrometer and was consistent with 3He proportional counter and NaI (Tl) gamma-ray spectrometer measurements. Plasma ion temperature values were deduced from the neutron spectrum in discharges with lower hybrid wave injection and ion cyclotron resonance heating. Scattered neutron spectra were simulated by the Monte Carlo transport Code, and they were well verified by the pulse height measurements at low energies.Comment: 19 pages,10 figures, 1 tabl

Insulation resistance degradation models of extruded power cables under thermal ageing

Insulation resistance (IR) is an essential metric indicating insulation conditions of extruded power cables. To deliver reliable IR simulation as a reference for practical cable inspection, in this paper, four IR degradation models for cross-linked polyethylene-insulated cables under thermal ageing are presented. In addition, the influences of methodologies and temperature profiles on IR simulation are evaluated. Cable cylindrical insulation is first divided into sufficiently small segments whose temperatures are simulated by jointly using a finite volume method and an artificial neural network to model the thermal ageing experiment conditions. The thermal degradation of IR is then simulated by dichotomy models that randomly sample fully degraded segments based on an overall insulation (layer) ageing condition estimation and discretization models that estimate the gradual degradation of individual segments, respectively. Furthermore, uniform and non-uniform temperature profiles are incorporated into dichotomy and discretization models, respectively, for a comparison. The IR simulation results are not only compared between different models, but also discussed around the sensitivity of IR simulation to segment sizes and degradation rates. This provides cable assessment engineers with insights into model behaviour as a reference for their selection of appropriate IR degradation models

Insulation resistance measurements of medium-voltage cross-linked polyethylene cables under thermal stresses

The insulation of medium-voltage electrical cables is usually composed of polymers such as cross-linked polyethylene (XLPE) that excel in electrical dielectric properties and thermomechanical reliability. Thermal stress is one of the key factors that degrade the insulation performance of heavily loaded cables and eventually cause irreversible cable failures. To inform XLPE insulation resistance (IR) changes which measure cable insulation conditions under thermal stresses and assist in the development of related IR models, this paper presents IR measurements of 10 kV XLPE power cables which were thermally aged at around 100 oC under an accelerated thermal ageing experiment. The yearlong IR observations exhibited two consecutive U-shape changes followed by a rough decline, which might reflect a joint effect of annealing and thermal ageing. The experiment results highlight the necessity of enhancing IR models to additionally consider the promotion of hopping conduction within insulation by the chemical components diffused from semicon layers under the annealing effects

Activation of Hepatic Stellate Cells is Inhibited by microRNA-378a-3p via Wnt10a

Background/Aims: Wnt/β-catenin pathway is involved in liver fibrosis and microRNAs (miRNAs) are considered as key regulators of the activation of hepatic stellate cells (HSCs). A recent study showed the protective role of miR-378a-3p against cardiac fibrosis. However, whether miR-378a-3p suppresses Wnt/β-catenin pathway in liver fibrosis is largely unknown. Methods: miR-378a-3p expression was detected in carbon tetrachloride-induced liver fibrosis and activated HSCs. Effects of miR-378a-3p overexpression on HSC activation and Wnt/β-catenin pathway were analyzed. Bioinformatic analysis was employed to identify the potential targets of miR-378a-3p. Serum miR-378a-3p expression was analyzed in patients with cirrhosis. Results: Reduced miR-378a-3p expression was observed in the fibrotic liver tissues and activated HSCs. Up-regulation of miR-378a-3p inhibited HSC activation including cell proliferation, α-smooth muscle actin (α-SMA) and collagen expression. Moreover, miR-378a-3p overexpression resulted in Wnt/β-catenin pathway inactivation. Luciferase reporter assays demonstrated that Wnt10a, a member of Wnt/β-catenin pathway, was confirmed to be a target of miR-378a-3p. By contrast, miR-378a-3p inhibitor contributed to HSC activation, with an increase in cell proliferation, α-SMA and collagen expression. But all these effects were blocked down by silencing of Wnt10a. Notably, sera from patients with cirrhosis contained lower levels of miR-378a-3p than sera from healthy controls. Receiver operating characteristic curve analysis suggested that serum miR-378a-3p differentiated liver cirrhosis patients from healthy controls, with an area under the curve of ROC curve of 0.916. Conclusion: miR-378a-3p suppresses HSC activation, at least in part, via targeting of Wnt10a, supporting its potential utility as a novel therapeutic target for liver fibrosis

Data_Sheet_1_Anticoagulant for treatment and prophylaxis of venous thromboembolism patients with renal dysfunction: A systematic review and network meta-analysis.docx

ObjectiveThe aim of this study was to compare the efficacy and safety for particular regimen and dosage in venous thromboembolism (VTE) patients with renal insufficiency.MethodsEnglish language searches of PubMed, Embase, and Web of Science (inception to May 2021). RCTs evaluating anticoagulants for VTE treatment at acute phase, extension phase, and VTE prophylaxis in patients with renal insufficiency and reporting efficacy (death, recurrence, or occurrence of VTE) and safety (bleeding) outcomes were selected. The methodological quality of each study included was assessed at the outcome level using the risk-of-bias assessment tool developed by the Cochrane Bias Methods Group.ResultsTwenty-one trials that involved 76,574 participants and 8,972 (11.7%) patients with renal insufficiency were enrolled, including 10 trials on VTE treatment in acute phase (3–12 months), four trials on VTE treatment in extension phase (6–36 months), and seven trials for VTE prophylaxis. For acute VTE treatment, compared with dabigatran etexilate, apixaban (RR 5.90, 95%CI 1.00–34.60) and rivaroxaban (RR 6.18, 95%CI 1.17–32.75) were significantly associated with increased risk of death or recurrence. For extension treatment of VTE, aspirin had the highest probability of the most effective and safest treatment, followed by apixaban. For VTE prophylaxis, compared with enoxaparin, desirudin was associated with lower risk of VTE occurrence (RR 0.56, 95% CI 0.34–0.91), but had higher risk of bleeding than dabigatran etexilate.ConclusionThe network meta-analysis informs the optimal choice of anticoagulants and their particular dosage for treatment and prophylaxis of VTE patients comorbid renal insufficiency.Systematic review registrationwww.crd.york.ac.uk/prospero/, identifier: CRD42021254086.</p

Neutron measurements from beam-target reactions at the ELISE neutral beam test facility

Measurements of 2.5 MeV neutron emission from beam-target reactions performed at the ELISE neutral beam test facility are presented in this paper. The measurements are used to study the penetration of a deuterium beam in a copper dump, based on the observation of the time evolution of the neutron counting rate from beam-target reactions with a liquid scintillation detector. A calculation based on a local mixing model of deuterium deposition in the target up to a concentration of 20% at saturation is used to evaluate the expected neutron yield for comparison with data. The results are of relevance to understand neutron emission associated to beam penetration in a solid target, with applications to diagnostic systems for the SPIDER and MITICA Neutral Beam Injection prototypes. (C) 2014 AIP Publishing LLC.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000345646000118&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Instruments &amp; InstrumentationPhysics, AppliedSCI(E)[email protected]

Neutron measurements from beam-target reactions at the ELISE neutral beam test facility

Measurements of 2.5 MeV neutron emission from beam-target reactions performed at the ELISE neutral beam test facility are presented in this paper. The measurements are used to study the penetration of a deuterium beam in a copper dump, based on the observation of the time evolution of the neutron counting rate from beam-target reactions with a liquid scintillation detector. A calculation based on a local mixing model of deuterium deposition in the target up to a concentration of 20% at saturation is used to evaluate the expected neutron yield for comparison with data. The results are of relevance to understand neutron emission associated to beam penetration in a solid target, with applications to diagnostic systems for the SPIDER and MITICA Neutral Beam Injection prototypes. (C) 2014 AIP Publishing LLC.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000345646000118&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Instruments &amp; InstrumentationPhysics, AppliedSCI(E)[email protected]

Morphology Defects Guided Pore Initiation during the Formation of Porous Anodic Alumina

Aluminum (Al) anodization leads to formation of porous structures with a broad spectrum of applications. Naturally or intentionally created defects on Al surfaces can greatly affect pore initiation. However, there is still a lack of systematic understanding on the defect dependent morphology evolution. In this paper, anodization processes on unpolished, polished, and nanoimprinted Al substrates are investigated under high voltages up to 600 V in various acid solutions. A porous structure is obtained on the unpolished and nanoimprinted Al foils with rough surface texture, whereas a compact film can be rationally obtained on the polished Al foil with a highly smooth surface. The observation of surface roughness dependent oxide film morphology evolution could be originated from the high voltages, which increases the threshold requirement of defect size or density for the pore initiation. Electrostatics simulation results indicate that inhomogeneous electric field and its corresponding localized high current induced by the surface roughness facilitate the initiation of nanopores. In addition, the porous films are utilized as templates to produce polydimethylsiloxane nanocone and submicrowire arrays. The nanoarrays with different aspect ratios present tunable wettability with the contact angles ranging from 144.6 degrees to 56.7 degrees, which hold promising potentials in microfluidic devices and self-cleaning coatings