Tamping the movement of the laser absorption cutoff position using gold foam hohlraum

In indirect-driven laser fusion experiments,the movement of the laser absorption layer will distort the radiation uniformity on the capsule.The gold foam has advantages in symmetry control and lowering wall plasma blowoff when used in an inertial confinement fusion(ICF)hohlraum.This work investigates the motion of the laser absorption cutoff position using lowdensity foam gold walls.It is found that the motion of the laser absorption cutoff position can be significantly mitigated through optimal initial low density,tailored to a specific laser shape.For a short square laser pulse,the laser absorption cutoff position remains almost stationary at an initial density of approximately 0.6 g cm^(-3).For a long-shaped laser pulse,the minimal motion of the laser absorption cutoff position is observed at an initial density of about 0.1 g cm^(-3).This approach allows for the adjustment of the symmetry of the hohlraum radiation source.The insights gained from this study serve as a crucial reference for optimizing the hohlraum wall density.

Measurement of 2p-3d absorption in a hot molybdenum plasma

We present measurements of the 2p-3d transition opacity of a hot molybdenum-scandium sample with nearly half-vacant molybdenum M-shell configurations.A plastic-tamped molybdenum-scandium foil sample is radiatively heated to high temperature in a compact D-shaped gold Hohlraum driven by∼30 kJ laser energy at the SG-100 kJ laser facility.X rays transmitted through the molybdenum and scandium plasmas are diffracted by crystals and finally recorded by image plates.The electron temperatures in the sample in particular spatial and temporal zones are determined by the K-shell absorption of the scandium plasma.A combination of the IRAD3D view factor code and the MULTI hydrodynamic code is used to simulate the spatial distribution and temporal behavior of the sample temperature and density.The inferred temperature in the molybdenum plasma reaches a average of 138±11 eV.A detailed configuration-accounting calculation of the n=2–3 transition absorption of the molybdenum plasma is compared with experimental measurements and quite good agreement is found.The present measurements provide an opportunity to test opacity models for complicated M-shell configurations.

Self-consistent and precise measurement of time-dependent radiative albedo of gold based on specially symmetrical triple-cavity Hohlraum

A self-consistent and precise method to determine the time-dependent radiative albedo,i.e.,the ratio of the reemission flux to the incident flux,for an indirect-drive inertial confinement fusion Hohlraum wall material is proposed.A specially designed symmetrical triple-cavity gold Hohlraum is used to create approximately constant and near-equilibrium uniform radiation with a peak temperature of 160 eV.The incident flux at the secondary cavity waist is obtained from flux balance analysis and from the shock velocity of a standard sample.The results agree well owing to the symmetrical radiation in the secondary cavity.A self-consistent and precise time-dependent radiative albedo is deduced from the reliable reemission flux and the incident flux,and the result from the shock velocity is found to have a smaller uncertainty than that from the multi-angle flux balance analysis,and also to agree well with the result of a simulation using the HYADES opacity.

Time-resolved K-shell x-ray spectra of nanosecond laser-produced titanium tracer in gold plasmas

A study of a nanosecond laser irradiation on the titanium-layer-buried gold planar target is presented. The timeresolved x-ray emission spectra of titanium tracer are measured by a streaked crystal spectrometer. By comparing the simulated spectra obtained by using the FLYCHK code with the measured titanium spectra, the temporal plasma states, i.e.,the electron temperatures and densities, are deduced. To evaluate the feasibility of using the method for the characterization of Au plasma states, the deduced plasma states from the measured titanium spectra are compared with the Multi-1D hydrodynamic simulations of laser-produced Au plasmas. By comparing the measured and simulated results, an overall agreement for the electron temperatures is found, whereas there are deviations in the electron densities. The experiment–theory discrepancy may suggest that the plasma state could not be well reproduced by the Multi-1D hydrodynamic simulation, in which the radial gradient is not taken into account. Further investigations on the spectral characterization and hydrodynamic simulations of the plasma states are needed. All the measured and FLYCHK simulated spectra are given in this paper as datasets. The datasets are openly available at http://www.doi.org/10.57760/sciencedb.j00113.00032.

Effects of ZrO_2 on the Performance of CuO-ZnO-Al_2O_3/HZSM-5 Catalyst for Dimethyl Ether Synthesis from CO_2 Hydrogenation

A series of composite catalysts were prepared by the wet mixing method, and the mass ratio of CuO-ZnO-Al2O3-ZrO2 component to HZSM-5 zeolite （molar ratio of SiO2 to Al2O3 being 25） was 2：1. The CuO-ZnO-Al2O3-ZrO2 （CuO/ZnO/Al2O3=3/6/1 by weight） component was prepared by a modified ＇two-step＇ co-precipitation method. The effects of ZrO2 on the performance of CuO-ZnO-Al2O3/HZSMo5 catalyst for dimethyl ether synthesis from CO2 hydrogenation were investigated. It was found that ZrO2 improved the properties of CuO-ZnO-Al2O3/HZSM-5 as a structural promoter.

Recent diagnostic developments at the 100 kJ-level laser facility in China

A 100 kJ-level laser facility has been designed to study inertial confinement fusion physics in China.This facility incorporates various diagnostic techniques,including optical,x-ray imaging,x-ray spectrum,and fusion product diagnostics,as well as general diagnostics assistance systems and central control and data acquisition systems.This paper describes recent developments in diagnostics at the facility.

Experimental and simulation studies of thermal transport based on plasma flow motion in laser-ablated dense regions of Au and CH

A practical experimental method is proposed to investigate thermal transport by characterizing the motion of plasma flows through a x-ray spectroscopic technique using tracers.By simultaneously measuring multiple parameters,namely,the mass-ablation rate,the temporal evolution of plasma flow velocities and trajectories and the temperature,it is possible to observe a variety of physical processes,such as shock wave compression,heating by thermal waves,and plasma thermal expansion,and to determine their relative importance in different phases during the irradiation of CH and Au targets.From a comparison with hydrodynamic simulations,we find significant differences in the motion of the plasma flows between CH and Au,which can be attributed to different sensitivities to the thermal transport process.There are also differences in the ablation and electron temperature histories of the two materials.These results confirm that velocities and trajectories of plasma motion can provide useful evidence in the investigation of thermal conduction,and the approach presented here deserves more attention in the context of inertial confinement fusion and high-energy-density physics.

Neddylation is required for herpes simplex virus type I （HSV- 1）-induced early phase interferon-beta production

Type I interferons such as interferon-beta （IFN-β） play essential roles in the host innate immune response to herpes simplex virus type I （HSV-1） infection. The transcription of type I interferon genes is controlled by nuclear factor-κB （NF-κB） and interferon regulatory factor （IRF） family members including IRF3. NF-κB activation depends on the phosphorylation of inhibitor of κB （IκB）, which triggers its ubiqitination and degradation. It has been reported that neddylation inhibition by a pharmacological agent MLN4924 potently suppresses lipopolysaccharide （LPS）-induced proinflammatory cytokine production with the accumulation of phosphorylated IκBa. However, the role of neddylation in type I interferon expression remains unknown. Here, we report that neddylation inhibition with MLN4924 or upon UBA3 deficiency led to accumulation of phosphorylated IκBa, impaired IκBa degradation, and impaired NF-κB nuclear translocation in the early phase of HSV-1 infection even though phosphorylation and nuclear translocation of IRF3 were not affected. The blockade of NF-κB nuclear translocation by neddylation inhibition becomes less efficient at the later time points of HSV-1 infection. Consequently, HSV- 1-induced early phase IFN-β production significantly decreased upon MLN4924 treatment and UBA3 deficiency. NF-κB inhibitor JSH-23 mimicked the effects of neddylation inhibition in the early phase of HSV-1 infection. Moreover, the effects of neddylation inhibition on HSV-1-induced early phase IFN-c production diminished in the presence of NF-κB inhibitor JSH-23. Thus, neddylation contributes to HSV-l-induced early phase IFN-β production through, at least partially, promoting NF-κB activation.

cAMP Modulates Macrophage Development by Suppressing M-CSF-Induced MAPKs Activation

M-CSF is a key cytokine in macrophage development by inducing MAPKs activation, and cAMP can inhibit MAPKs activation induced by inflammatory stimuli. To explore the effects of cAMP on M-CSF-induced MAPKs activation and on macrophage development, the model of bone marrow-derived murine macrophages （BMMs） was used. The effects of cAMP on M-CSF-induced MAPKs activation were analyzed by Western blotting assay, and the effects of cAMP on CD14 and F4/80 expression during macrophage development were examined by FACS analysis. Macrophage morphology showed the successful establishment of the model of macrophage development. Western blotting assay revealed that M-CSF activated ERK, JNK and p38 in both mature and immature macrophages, and cAMP inhibited M-CSF-induced ERK, JNK and p38 activation in a time-dependent manner. FACS analysis revealed that macrophage development was impaired with cAMP pretreatment. In conclusion, cAMP modulates macrophage development by suppressing M-CSF-induced MAPKs activation. Cellular ＆ Molecular Immunology.

SHP limits TLR signaling, an inducible transcriptional corepressor

Toll-like receptor(TLR)signaling stimulated by diverse microbial components plays a pivotal role in innate immunity by eliciting a powerful proinflammatory response that is essential for pathogen elimination.However,uncontrolled inflammation can result in tissue damage.Thus,TLR signaling has to be tightly controlled to maintain immune balance in the organism.The paradigm for modulating TLR signaling seems to center on the canonical nuclear factor-kB(NF-kB)pathway,most likely because of the central role of NF-kB in the production of various proinflammatory cytokines.1 In a recent issue of Nature Immunology,Yuk et al.have reported the identification of a novel endogenous NF-kB inhibitor in TLR signaling—small heterodimer partner(SHP)2 Interestingly,SHP functions in a self-regulating system:TLR signaling induces the expression of SHP in macrophages through Ca21-dependent activation of AMP-activated protein kinase(AMPK),which has anti-inflammatory effects3 SHP in turn decreases the expression of proinflammatory cytokines such as tumor necrosis factor-a(TNF-a)by physically binding to two key components of the canonical NF-kB pathway,namely,RelA/p65 and TNF receptorassociated factor 6(TRAF6)This work demonstrates an essential role for SHP in the negative control of TLR signaling and provides a novel underlying molecular mechanism.

The Characteristic of an Anti-Human DR5 Antibody A6

The efficacy of many cancer treatments is due to their ability to induce apoptosis. DR5 can activate apoptosis pathway after binding with its natural ligand, tumour necrosis factor-related apoptosis-inducing ligand （TRAIL/ Apo2L）. Both TRAIL and agonistic anti-DR5 monoclonal antibody are currently being explored for cancer therapy. The mechanisms of cytotoxicity of our previously prepared monoclonal antibody A6 against DR5 were investigated here. A6 could cause viability loss of Jurkat cells in both time- and dose-dependent manner which could be attributed to the activation of apoptosis pathway. Caspases 3, 8 and 9 were activated in Jurkat cells and the caspase specific inhibitors, such as broad caspases inhibitor Z-VAD-FMK, caspase 8 specific inhibitor Z-IETDFMK and caspase 9 specific inhibitor Z-LEHD-FMK could recover the viability loss caused by A6. The function and molecular mechanism of TRAIL-mediated apoptosis were also investigated and compared with those of A6. Although A6 and TRAIL recognize a different epitope, they could induce a similar reaction in Jurkat cells.

Roles of neddylation against viral infections

The ubiquitin-dependent proteasome pathway can be hijacked by certain viruses to maintain viral genome amplification.A key class of ubiquitin-E3s involved in this pathway is Cullin-RING ligases(CRLs),which are activated by an additional ubiquitin-like protein NEDD8.1 The process by which the ubiquitin-like protein NEDD8 is conjugated to its target proteins is officially named‘neddylation’.Consequently,neddylation inhibition,through the use of the pharmacological inhibitor MLN4924,might prevent viral genome amplification.