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1.
Sci Rep ; 14(1): 14785, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926535

RESUMO

Direct laser acceleration (DLA) of electrons in plasmas of near-critical density (NCD) is a very advancing platform for high-energy PW-class lasers of moderate relativistic intensity supporting Inertial Confinement Fusion research. Experiments conducted at the PHELIX sub-PW Nd:glass laser demonstrated application-promising characteristics of DLA-based radiation and particle sources, such as ultra-high number, high directionality and high conversion efficiency. In this context, the bright synchrotron-like (betatron) radiation of DLA electrons, which arises from the interaction of a sub-ps PHELIX laser pulse with an intensity of 1019 W/cm2 with pre-ionized low-density polymer foam, was studied. The experimental results show that the betatron radiation produced by DLA electrons in NCD plasma is well directed with a half-angle of 100-200 mrad, yielding (3.4 ± 0.4)·1010 photons/keV/sr at 10 keV photon energy. The experimental photon fluence and the brilliance agree well with the particle-in-cell simulations. These results pave the way for innovative applications of the DLA regime using low-density pre-ionized foams in high energy density research.

2.
J Hum Nutr Diet ; 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38944880

RESUMO

BACKGROUND: Adequate nutritional knowledge and healthy dietary behaviours are essential for promoting rational nutrition for children. However, lack of nutritional knowledge and unhealthy dietary behaviours are common among Chinese children. Therefore, we developed a school-based nutrition education (NE) program to assess its impacts on nutritional knowledge and dietary behaviours in pupils. METHODS: In this trial, one school was assigned as an intervention group (n = 199) and the other two schools were designated as a control group (n = 140). Children in the intervention group received the NE program in addition to their regular health curriculum, whereas the control group continued with their usual health curriculum without any NE program materials. RESULTS: Concerning nutritional knowledge, the mean difference (follow-up minus baseline) of average knowledge scores in the intervention group was significantly higher than that in the control group (1.99 ± 3.22 vs. 0.66 ± 3.60, p = 0.001). However, subgroup analysis revealed that this difference disappeared among boys and students with malnutrition status. Regarding dietary behaviours, the NE program significantly increased the proportion of children exhibiting high frequencies of meat and nuts consumption in the intervention group, along with diverse food choice at breakfast. Additionally, it markedly reduced the proportion of children exhibiting high frequencies of sugar-sweetened beverages and fast food consumption. Structural equation modelling analyses indicated a significant direct effect of NE intervention on nutritional knowledge and an indirect effect on dietary behaviours. CONCLUSIONS: The NE program effectively enhanced nutritional knowledge scores and further improved dietary behaviours among Chinese primary school students. Future NE programs should pay more attention to boys and children with malnutrition.

3.
J Clin Psychopharmacol ; 44(3): 297-301, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38506608

RESUMO

PURPOSE: This systematic review aimed to investigate the clinical manifestations and characteristics of venlafaxine-associated rhabdomyolysis. METHODS: A systematic search was conducted in PubMed, Elsevier, Science Direct, Embase, Springer Link, Wiley Online Library, CNKI, and Wanfang databases from the date of database inception to January 2023. Previously reported cases of venlafaxine-associated rhabdomyolysis were identified, and relevant data from these cases were collected for descriptive statistical analysis. Cases that met the inclusion criteria were evaluated to determine the correlation between adverse reactions and venlafaxine. RESULTS: A total of 12 patients with venlafaxine-associated rhabdomyolysis were included. None of these patients had a history of muscle pain or discomfort. Of the 12 patients, 5 patients received venlafaxine at doses of ≤225 mg/d, whereas the remaining 7 patients received doses exceeding 225 mg/d. The main clinical symptoms included myalgia, muscle weakness, and renal injury. All 12 patients discontinued venlafaxine and received symptomatic care. CONCLUSIONS: Venlafaxine, used either as a monotherapy or in combination with other drugs, may be associated with rhabdomyolysis. Creatine kinase levels may normalize or significantly decrease after discontinuation of venlafaxine and symptomatic treatment.


Assuntos
Rabdomiólise , Cloridrato de Venlafaxina , Rabdomiólise/induzido quimicamente , Cloridrato de Venlafaxina/efeitos adversos , Cloridrato de Venlafaxina/administração & dosagem , Humanos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Creatina Quinase/sangue , Mialgia/induzido quimicamente
4.
Phys Rev Lett ; 130(9): 095101, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36930918

RESUMO

We report on charge state measurements of laser-accelerated carbon ions in the energy range of several MeV penetrating a dense partially ionized plasma. The plasma was generated by irradiation of a foam target with laser-induced hohlraum radiation in the soft x-ray regime. We use the tricellulose acetate (C_{9}H_{16}O_{8}) foam of 2 mg/cm^{3} density and 1 mm interaction length as target material. This kind of plasma is advantageous for high-precision measurements, due to good uniformity and long lifetime compared to the ion pulse length and the interaction duration. We diagnose the plasma parameters to be T_{e}=17 eV and n_{e}=4×10^{20} cm^{-3}. We observe the average charge states passing through the plasma to be higher than those predicted by the commonly used semiempirical formula. Through solving the rate equations, we attribute the enhancement to the target density effects, which will increase the ionization rates on one hand and reduce the electron capture rates on the other hand. The underlying physics is actually the balancing of the lifetime of excited states versus the collisional frequency. In previous measurement with partially ionized plasma from gas discharge and z pinch to laser direct irradiation, no target density effects were ever demonstrated. For the first time, we are able to experimentally prove that target density effects start to play a significant role in plasma near the critical density of Nd-glass laser radiation. The finding is important for heavy ion beam driven high-energy-density physics and fast ignitions. The method provides a new approach to precisely address the beam-plasma interaction issues with high-intensity short-pulse lasers in dense plasma regimes.

5.
Front Public Health ; 10: 986954, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091568

RESUMO

Objective: Undoubtedly, the relationship between serum uric acid (SUA) and obesity is less data for Chinese patients with obesity. This study aimed to examine the prevalence of hyperuricemia (HUA) and the association between SUA and patients with obesity. Methods: All participants were categorized as overweight, obesity I, obesity II, and obesity III. In addition, based on SUA concentration, the participants were stratified into four quartiles. The authors used descriptive analysis, independent t-test, ANOVA, correlation analysis, and multiple linear regression models to verify the SUA level and obesity among Chinese adults. Results: Overall, the estimated prevalence of HUA was 69.8%. In the BMI categories, the prevalence of HUA was 5.1% in overweight, 15.2% in obesity I, 16.9% in obesity II, and 32.5% in obesity III. Correlation analysis shows that SUA is strongly correlated with BMI, waist circumference (WC), and hip circumference (HC). Multiple linear regression analysis shows that high density-lipoprotein cholesterol (HDL-C) is a protective predictor of serum uric acid levels in patients with obesity. Compared with the overweight, obesity I, obesity II, and obesity III were more likely to have higher levels in the SUA levels. Conclusion: We mainly showed that the serum uric acid levels in Chinese patients with severe obesity declined slightly as age increased.


Assuntos
Hiperuricemia , Obesidade Mórbida , Adulto , China/epidemiologia , Humanos , Hiperuricemia/epidemiologia , Obesidade/epidemiologia , Sobrepeso , Prevalência , Estudos Retrospectivos , Ácido Úrico
6.
Nat Commun ; 11(1): 5157, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33057005

RESUMO

Intense particle beams generated from the interaction of ultrahigh intensity lasers with sample foils provide options in radiography, high-yield neutron sources, high-energy-density-matter generation, and ion fast ignition. An accurate understanding of beam transportation behavior in dense matter is crucial for all these applications. Here we report the experimental evidence on one order of magnitude enhancement of intense laser-accelerated proton beam stopping in dense ionized matter, in comparison with the current-widely used models describing individual ion stopping in matter. Supported by particle-in-cell (PIC) simulations, we attribute the enhancement to the strong decelerating electric field approaching 1 GV/m that can be created by the beam-driven return current. This collective effect plays the dominant role in the stopping of laser-accelerated intense proton beams in dense ionized matter. This finding is essential for the optimum design of ion driven fast ignition and inertial confinement fusion.

7.
Sci Rep ; 7(1): 6482, 2017 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-28743901

RESUMO

Secondary electron emission yield from the surface of SiC ceramics induced by Xe17+ ions has been measured as a function of target temperature and incident energy. In the temperature range of 463-659 K, the total yield gradually decreases with increasing target temperature. The decrease is about 57% for 3.2 MeV Xe17+ impact, and about 62% for 4.0 MeV Xe17+ impact, which is much larger than the decrease observed previously for ion impact at low charged states. The yield dependence on the temperature is discussed in terms of work function, because both kinetic electron emission and potential electron emission are influenced by work function. In addition, our experimental data show that the total electron yield gradually increases with the kinetic energy of projectile, when the target is at a constant temperature higher than room temperature. This result can be explained by electronic stopping power which plays an important role in kinetic electron emission.

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