Laboratory evidence of Weibel magnetogenesis driven by temperature gradient using three-dimensional synchronous proton radiography.

The origin of the cosmic magnetic field remains an unsolved mystery, relying not only on specific dynamo processes but also on the seed field to be amplified. Recently, the diffuse radio emission and Faraday rotation observations reveal that there has been a microgauss-level magnetic field in intracluster medium in the early universe, which places strong constraints on the strength of the initial field and implies the underlying kinetic effects; the commonly believed Biermann battery can only provide extremely weak seed of 10-21 G. Here, we present evidence for the spontaneous Weibel-type magnetogenesis in laser-produced weakly collisional plasma with the three-dimensional synchronous proton radiography, where the distribution anisotropy directly arises from the temperature gradient, even without the commonly considered interpenetrating plasmas or shear flows. This field can achieve sufficient strength and is sensitive to Coulomb collision. Our results demonstrate the importance of kinetics in magnetogenesis in weakly collisional astrophysical scenarios.

Symptom burden survey and symptom clusters in patients with cervical cancer: a cross-sectional survey.

PURPOSE: The purpose of this study is to determine the incidence and severity of symptoms of patients with cervical cancer within 6 months after radiotherapy and chemotherapy, form a symptom burden report, evaluate the distribution characteristics of symptoms, identify symptom clusters, and provide a basis for clinical doctors and nurses to improve the symptom management of patients with cervical cancer after radiotherapy and chemotherapy. METHODS: The patients with cervical cancer within 6 months after radiotherapy and chemotherapy were recruited to investigate their symptom burden. Exploratory factor analysis was used to identify symptom clusters. RESULTS: A total of 250 patients participated in the study. The study found that the most common symptom among the 40 symptoms was fatigue, and the most serious symptom was nocturia. Based on the occurrence rate and severity of symptoms, nine symptom clusters were identified, including psycho-emotion-related symptom cluster, pain-disturbed sleep-related symptom cluster, menopausal symptom cluster, tinnitus-dizziness-related symptom cluster, urinary-related symptom cluster, dry mouth-bitter taste-related symptom cluster, intestinal-related symptom cluster, memory loss-numbness-related symptom cluster, and emaciation-related symptom cluster. The three most serious symptom clusters are pain-disturbed sleep-related symptom cluster, urinary-related symptom cluster, and memory loss-numbness-related symptom cluster. CONCLUSION: The symptoms of patients with cervical cancer within 6 months after radiotherapy and chemotherapy are complex, and nine symptom clusters can be identified according to the incidence and severity of symptoms. We can find the potential biological mechanism of each symptom cluster through the discussion of previous mechanism research and clinical research. The number of symptom clusters and the number of symptoms within the symptom cluster are closely related to the symptom evaluation scale selected for the study. Therefore, the symptom cluster study urgently needs a targeted symptom evaluation scale that can comprehensively reflect the patient's condition.

Toward 3D imaging of femtosecond laser filament in air by a CCD within a single exposure.

We experimentally demonstrated the 3D propagation of laser filament in air by an Fabry-Pérot (F-P) cavity assisted imaging within a single exposure. The F-P cavity was composed of two parallel mirrors with certain reflectivity and transmission at filament laser, so that the beam was reflected and refracted multiple times between the two mirrors. The cross-sectional intensity patterns at different longitudinal positions along filament within a single exposure of CCD (Charge-coupled Device) were recorded. When keeping the incident angle of the F-P cavity as a constant and reducing its spacing distance, a better longitudinally resolved evolution of cross-sectional filament intensity patterns was obtained. The intensity evolution along laser filament by the F-P cavity assisted imaging method was consistent with the filament fluorescence measurement from the side. As an application, the transition of laser propagation from linear to nonlinear was unveiled by the F-P cavity assisted 3D imaging.

Manufacture of TiO2 nanoparticles with high preparation efficiency and photocatalytic performance by controlling the parameters of pulsed laser ablation in liquid.

This study proposes a method to improve the production efficiency and photocatalytic performance of TiO2 nanoparticles using the pulsed laser ablation in liquid (PLAL) method to optimise preparation parameters. In this study, the variation of particle size, morphology, preparation, and catalytic efficiency due to the increase in the number of pulses is studied. The mechanism of particle morphology change is analysed using thermodynamic simulation. The density functional theory (DFT) is used to calculate and characterise the reason why the special structure formed by particle breaking improves the photocatalytic performance. In addition, the influence of the law of solution height on particle breakage is summarised to obtain an optimised preparation parameter. The proposed method provides a reference for the selection of parameters in actual production.

Revealing the Mechanism of Astragali Radix against Cancer-Related Fatigue by Network Pharmacology and Molecular Docking.

BACKGROUND: Cancer-related fatigue (CRF) is an increasingly appreciated complication in cancer patients, which severely impairs their quality of life for a long time. Astragali Radix (AR) is a safe and effective treatment to improve CRF, but the related mechanistic studies are still limited. OBJECTIVE: To systematically analyze the mechanism of AR against CRF by network pharmacology. METHODS: TCMSP was searched to obtain the active compounds and targets of AR. The active compound-target (AC-T) network was established and exhibited by related visualization software. The GeneCards database was searched to acquire CRF targets, and the intersection targets with AR targets were used to make the Venny diagram. The protein-protein interaction (PPI) network of intersection targets was established, and further, the therapeutic core targets were selected by topological parameters. The selected core targets were uploaded to Metascape for GO and KEGG analysis. Finally, AutoDock Vina and PyMOL were employed for molecular docking validation. RESULTS: 16 active compounds of AR were obtained, such as quercetin, kaempferol, 7-O-methylisomucronulatol, formononetin, and isorhamnetin. 57 core targets were screened, such as AKT1, TP53, VEGFA, IL-6, and CASP3. KEGG analysis manifested that the core targets acted on various pathways, including 137 pathways such as TNF, IL-17, and the AGE-RAGE signaling pathway. Molecular docking demonstrated that active compounds docked well with the core targets. CONCLUSION: The mechanism of AR in treating CRF involves multiple targets and multiple pathways. The present study laid a theoretical foundation for the subsequent research and clinical application of AR and its extracts against CRF.

An angular-resolved multi-channel Thomson parabola spectrometer for laser-driven ion measurement.

A multi-channel Thomson parabola spectrometer was designed and employed to diagnose ion beams driven by intense laser pulses. Angular-resolved energy spectra for different ion species can be measured in a single shot. It contains parallel dipole magnets and wedged electrodes to fit ion dispersion of different charge-to-mass ratios. The diameter and separation of the entrance pinhole channels were designed properly to provide sufficient resolution and avoid overlapping of dispersed ion beams. To obtain a precise energy spectral resolving, three-dimensional distributions of the electric and magnetic fields were simulated. Experimental measurement of energy-dependent angular distributions of target normal sheath accelerated protons and deuterons was demonstrated. This novel compact design provides a comprehensive characterization for ion beams.

Multi-petawatt laser facility fully based on optical parametric chirped-pulse amplification.

We report on a multi-petawatt 3-cascaded all-optical parametric chirped-pulse amplification laser facility. The experimental results demonstrate that the maximum energy after the final amplifier and after the compressor is 168.7 J and 91.1 J, respectively. The pulse width (FWHM) is 18.6 fs in full width at half maximum after optimization of pulse compression. Therefore, 4.9 PW peak power has been achieved for the laser facility. To the best of our knowledge, this is the highest peak power reported so far for an all-optical parametric chirped-pulse amplification facility, and a compressed pulse shorter than 20 fs is achieved in a PW-class laser facility for the first time.

Design and optimization of the seed pulse generation scheme for precise beam synchronization in the Xingguang-III laser.

Xingguang-III is a large hybrid optical parametric amplification/chirped pulse amplification laser that outputs synchronized femtosecond, picosecond, and nanosecond beams with three different wavelengths, i.e., 800, 1053, and 527 nm, respectively. We present here an in-house front-end system design that generates the 1053 nm seed laser for the ps/ns beam directly from the 800 nm femtosecond laser, which enables the three beams to have intrinsic synchronization. The results show that a seed laser of 140 µJ energy and 1053 nm central wavelength with 34 nm spectral width (FWHM) is generated and the shot-to-shot timing jitter (peak-to-valley) between the fs and the ps beam is less than 1.32 ps.

High dispersive mirrors for erbium-doped fiber chirped pulse amplification system.

We report on the development of near-infrared high dispersive mirrors (HDM) with a group delay dispersion (GDD) of -2000 fs2. A HDM pair based on one optimized result at two reference wavelengths (1550 nm and 1560 nm) can reduce the total oscillation of the GDD effectively in the wavelength range of 1530-1575 nm. This HDM pair is designed and fabricated in a single coating run by means of the nonuniformity in film deposition. For the first time, near-infrared HDMs with two different reference wavelengths have been successfully applied in an erbium-doped fiber chirped pulse amplification system for the compression of 4.73 ps laser pulses to 380 fs.

Coherent combination of femtosecond pulses via non-collinear cross-correlation and far-field distribution.

We propose and demonstrate a method for active parallel coherent combinations of ultra-short laser pulses. The relative synchronization error, piston, and tilt between combined beams are controlled based on the non-collinear cross-correlation and the far-field distribution. In a proof-of-principle experiment, two 29.8 fs pulses are coherently combined with the combining efficiency as high as 99%. This study opens up a way to further scale the peak intensity and provides support for the next-generation ultra-intense laser systems.

Chirped-pulse amplification system based on chirp reversal and near-field spatial reversal with common tiled grating pair as stretcher and compressor.

Chirped-pulse amplification system based on chirp reversal in optical parametric chirped-pulse amplification is proposed and experimentally demonstrated. The operation of this system can be described as negative stretching-temporal chirp reversal-energy amplification-negative compression, in which the pulse is stretched and compressed with the same gratings. Stand-alone stretcher adopting lenses or concave mirrors with large aperture can be omitted. Simulations showed that this work mode can also increase the cut-off band-pass of the whole system and increase the output energy by 15-17%. In addition, the stability of a tiled-grating compressor can be improved with this work mode.