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1.
Phys Rev E ; 109(3-2): 035205, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38632769

RESUMEN

The double-cone ignition (DCI) scheme has been proposed as one of the alternative approaches to inertial confinement fusion, based on direct-drive and fast-ignition, in order to reduce the requirement for the driver energy. To evaluate the conical implosion energetics from the laser beams to the plasma flows, a series of experiments have been systematically conducted. The results indicate that 89%-96% of the laser energy was absorbed by the target, with moderate stimulated Raman scatterings. Here 2%-6% of the laser energy was coupled into the plasma jets ejected from the cone tips, which was mainly restricted by the mass reductions during the implosions inside the cones. The supersonic dense jets with a Mach number of 4 were obtained, which is favorable for forming a high-density, nondegenerated plasma core after the head-on collisions. These findings show encouraging results in terms of energy transport of the conical implosions in the DCI scheme.

2.
Diabetes Metab Res Rev ; 38(1): e3477, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34041844

RESUMEN

AIMS: Glycated albumin (GA) is a biomarker for short-term (2-3 weeks) glycaemic control. However, the predictive utility of GA for diabetes and prediabetes is largely uncharacterised. We aimed to investigate the relationships of baseline serum GA levels with incident diabetes and prediabetes. METHODS: This was a longitudinal cohort study involving 516 subjects without diabetes or prediabetes at baseline. Blood glucose levels were observed during follow-up. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using COX proportional hazard models. Receiver operating characteristic curves and areas under the curves (AUCs) were used to evaluate the discriminating abilities of glycaemic biomarkers and prediction models. RESULTS: During a 9-year follow-up, 51 individuals (9.88%) developed diabetes and 92 (17.83%) prediabetes. Unadjusted HRs (95% CI) for both diabetes and prediabetes increased proportionally with increasing GA levels in a dose-response manner. Multivariable-adjusted HRs (95% CI) for diabetes were significantly elevated from 1.0 (reference) to 5.58 (1.86-16.74). However, the trend was no longer significant for prediabetes after multivariable adjustment. AUCs for GA, fasting blood glucose (FBG) and 2-h postprandial blood glucose (2h-PBG) for predicting diabetes were 0.698, 0.655 and 0.725, respectively. The AUCs for GA had no significant differences compared with those for FBG (p = 0.376) and 2h-PBG (p = 0.552). Replacing FBG or 2h-PBG or both with GA in diabetes prediction models made no significant changes to the AUCs of the models. CONCLUSIONS: GA is of good prognostic utility in predicting diabetes. However, GA may not be a useful biomarker for predicting prediabetes.


Asunto(s)
Diabetes Mellitus Tipo 2 , Estado Prediabético , Biomarcadores , Glucemia , Estudios de Cohortes , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiología , Hemoglobina Glucada/análisis , Productos Finales de Glicación Avanzada , Humanos , Estudios Longitudinales , Estado Prediabético/diagnóstico , Estado Prediabético/epidemiología , Estudios Retrospectivos , Albúmina Sérica , Albúmina Sérica Glicada
3.
Anal Chem ; 92(13): 9048-9056, 2020 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-32412744

RESUMEN

Developing miniaturized and rapid protein analytical platforms is urgently needed for on-site protein analysis, which is important for disease diagnosis and monitoring. Liquid marbles (LMs), a kind of particle-coated droplets, as ideal microreactors have been used in various fields. However, their application as analytical platforms is limited due to the difficulty of pretreating complex samples in simple LMs. Herein, inspired by the microfluidic chip, we propose a strategy through fabricating fluid channels using deformable LM, termed liquid plasticine (LP), to achieve sample pretreatment function. Through combining isoelectric focusing (IEF) with an LP channel, an LP-IEF platform with simultaneous protein separation and concentration functions is realized. The pretreatment capability of the LP-IEF system for proteins in physiological samples is proven using standard proteins and human serum with the results of a clear separation, 10-fold concentration, and a resolution of 0.03 pH. Through cutting the LP after IEF to LMs and transiting isolated LMs containing target proteins for further downstream colorimetric and mass spectrometry measurements, the quantitative analysis of clinical microalbuminuria and identification of α-1-microglobulin/bikunin precursor in clinical diabetic urine samples are achieved. This work proposes a strategy to develop LMs/LPs as a multifunctional integrated analytical platform and the miniaturized LP-IEF device as a rapid protein analytical platform.


Asunto(s)
Focalización Isoeléctrica/métodos , alfa-Macroglobulinas/orina , Colorimetría , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patología , Diseño de Equipo , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica/instrumentación , Espectrometría de Masas , Compuestos Orgánicos/química , Dióxido de Silicio/química
4.
Sci Rep ; 8(1): 463, 2018 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-29323147

RESUMEN

When comets interacting with solar wind, straight and narrow plasma tails will be often formed. The most remarkable phenomenon of the plasma tails is the disconnection event, in which a plasma tail is uprooted from the comet's head and moves away from the comet. In this paper, the interaction process between a comet and solar wind is simulated by using a laser-driven plasma cloud to hit a cylinder obstacle. A disconnected plasma tail is observed behind the obstacle by optical shadowgraphy and interferometry. Our particle-in-cell simulations show that the difference in thermal velocity between ions and electrons induces an electrostatic field behind the obstacle. This field can lead to the convergence of ions to the central region, resulting in a disconnected plasma tail. This electrostatic-field-induced model may be a possible explanation for the disconnection events of cometary tails.

5.
Sci Rep ; 7: 42915, 2017 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-28266497

RESUMEN

A pair of collisionless shocks that propagate in the opposite directions are firstly observed in the interactions of laser-produced counter-streaming flows. The flows are generated by irradiating a pair of opposing copper foils with eight laser beams at the Shenguang-II (SG-II) laser facility. The experimental results indicate that the excited shocks are collisionless and electrostatic, in good agreement with the theoretical model of electrostatic shock. The particle-in-cell (PIC) simulations verify that a strong electrostatic field growing from the interaction region contributes to the shocks formation. The evolution is driven by the thermal pressure gradient between the upstream and the downstream. Theoretical analysis indicates that the strength of the shocks is enhanced with the decreasing density ratio during both flows interpenetration. The positive feedback can offset the shock decay process. This is probable the main reason why the electrostatic shocks can keep stable for a longer time in our experiment.

6.
Phys Rev Lett ; 108(21): 215001, 2012 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-23003270

RESUMEN

Reconnection of the self-generated magnetic fields in laser-plasma interaction was first investigated experimentally by Nilson et al. [Phys. Rev. Lett. 97, 255001 (2006)] by shining two laser pulses a distance apart on a solid target layer. An elongated current sheet (CS) was observed in the plasma between the two laser spots. In order to more closely model magnetotail reconnection, here two side-by-side thin target layers, instead of a single one, are used. It is found that at one end of the elongated CS a fanlike electron outflow region including three well-collimated electron jets appears. The (>1 MeV) tail of the jet energy distribution exhibits a power-law scaling. The enhanced electron acceleration is attributed to the intense inductive electric field in the narrow electron dominated reconnection region, as well as additional acceleration as they are trapped inside the rapidly moving plasmoid formed in and ejected from the CS. The ejection also induces a secondary CS.

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