A hybrid simulator with novel bicone-wire grid antenna.

The simulator is an indispensable device for the study of high-altitude electromagnetic pulse (HEMP) effects. In order to improve the quality of the electric field waveforms of the HEMP simulator, we carried out simulation and experimental studies for the biconical-wire grid antenna. A new bicone-wire grid antenna HEMP simulator was designed by using skeletonized cones instead of solid cones, which can substantially improve the mobility of the simulator. The effects of different aspect ratios and different cone structures of the simulator on the waveform and distribution characteristics of the electric field were analyzed. The accuracy of the simulation results was verified by testing the bicone-wire grid antenna simulator with the new structure. The results obtained are as follows: First, the simulator can provide a HEMP environment compliant with the International Electrotechnical Commission (IEC) standard in an area of 5 × 6 × 2 m3. Second, the simulator possesses optimal waveform quality and working space among simulators with different aspect ratios. Finally, the influence of using skeletonized cones instead of solid cones on the simulator's electric field waveforms is negligible, and the mobility of the new simulator is significantly improved compared to the original simulator.

The effect of initial electrons generation approaches on nanosecond pulsed breakdown characteristics.

In this paper, the effects of initial electrons generation approaches on nanosecond pulsed breakdown characteristics are analyzed. Based on the numerical simulations with a 3D PIC-MCC model, the impacts of field-enhancement factor and initial electron concentration on nanosecond pulsed breakdown characteristics are investigated. Three types of switches are designed and subjected to testing under pulse voltages with rise times of 40, 70, and 120 ns, respectively. The results can be summarized as follows. First, the field-enhancement factor and initial electron concentration have significant influences on the development of the discharge channel. Second, the cathode-grooved self-triggered switch exhibits lower breakdown time delay jitter than the hemispherical self-breakdown switch at low pressure, while the differences in jitter between the two switches become negligible at high pressure. Third, the cathode-grooved self-triggered switch shows a lower breakdown time delay jitter compared to the pre-ionization self-triggered switch for pulse voltages with rise times of 40 and 70 ns. Conversely, this trend reverses for pulse voltage with a rise time of 120 ns. Finally, the breakdown time delay jitter for both the cathode-grooved self-triggered switch and the pre-ionization self-triggered switch has been reduced, and both switches are suitable for different operating requirements and conditions.

Lower PTEN may be associated with CD8+ T cell exhaustion in diffuse large B-cell lymphoma.

Initially discovered in chronic viral infection and then extended to tumor, 'T-cell exhaustion' is a broad term describing the response of T cells to chronic antigen stimulation. By definition, whether T-cell exhaustion occurs in diffuse large B-cell lymphoma (DLBCL) remains largely unknown because little has been described. Here, the immune-suppressing checkpoint molecules involved in T-cell exhaustion, including PD-1, PD-L1, TIM-3 and TIGIT, whose expression levels were analyzed in DLBCL, were retrieved from the GEPIA database. Compared with the normal control, CD8A, TNFA, IFNG and GZMA were markedly elevated in DLBCL, indicating that infiltrated CD8+ T cells predominate in DLBCL. Meanwhile, inhibitory immune checkpoints, such as PD-1, PD-L1, TIGIT and TIM-3 were drastically higher in DLBCL. PTEN, WNT2 and DKK3 expression were also appraised. It was revealed that PTEN was lower in DLBCL, without being statistically significant. In contrast with PTEN, DKK3 and WNT2 were shown to be pronouncedly higher in DLBCL relative to the normal control. Prognostically, only TIGIT was found to be associated with overall survival in DLBCL. Collectively, all the data we curetted from the GEPIA and TIMER 2.0 databases explicitly indicate that CD8+ T cell exhaustion took place, which may be linked with lower PTEN in DLBCL. To the best of our knowledge, this is the first bioinformatic report explicitly proposing that CD8+ T cell exhaustion occurs in DLBCL, which may be associated with lower PTEN.

The immune checkpoint expression in the tumor immune microenvironment of DLBCL: Clinicopathologic features and prognosis.

Background & aims: The immune checkpoint recently provides a new strategy for the immunotherapy of malignant tumors. However, the role in the immune microenvironment of DLBCL is not completely clear. Methods: We detected the expression of PD-1, LAG-3, TIM-3, and TIGIT on TILs and on tumor cells among 174 DLBCL patients by IHC. Results: In TILs, the positive rates of PD-1, LAG-3, TIM-3 and TIGIT were 79.3%, 78.8%, 62.7% and 69.5%, respectively.TIM-3 and TIGIT were expressed in 44.8% and 45.4% of tumor cells. The expression of TIM-3 in TILs was significantly correlated with the Ann-Arbor stage (P=0.039). There was a positive correlation Between PD-1 and LAG-3 or TIM-3 and TIGIT.In addition, LAG-3 expression in TILs was associated with inferior prognosis.Multivariate analysis showed that PS score and R-CHOP therapy were independent risk factors for OS and PFS in patients with DLBCL (P=0.000). Conclusions: The expression level of TIM-3 is closely related to the Ann-Arbor stage, which may be expected to be a new index to evaluate the invasiveness of DLBCL. PD-1 was correlated with the expression of LAG-3, and the high expression of LAG-3 and LAG-3/PD-1 predicted the poor prognosis of DLBCL. Therefore, LAG-3 may become a new target of immunotherapy, or be used in combination with PD-1 inhibitors to improve the drug resistance of current patients with DLBCL.

Compact pulse generator with sub-nanosecond rise time based on inductance of order of several nH.

Pulse generators with a sub-nanosecond rise time are typically used to calibrate measurement probes in electromagnetic pulses. However, the technological dilemma between high voltage and low inductance has not been adequately addressed in this context. In this paper, the authors investigate the effects of the circuit and structural parameters on the generator. To reduce the rise time of the output voltage of the generator to a few hundred picoseconds, the inductance of its structure and the spark gap needs to be strictly controlled. We use SF6 at 1 MPa as an insulating gas for the spark gap to reduce the inductance of the capacitor and the switch to the order of several nH. The results of theoretical calculations and simulations were used to design and test two generators that used a coaxial ceramic capacitor and three plate ceramic capacitors, respectively. The experimental results showed that a double-exponential pulse voltage with a sub-nanosecond rise time could be obtained in a 50 Ω transmission line in both generators. The generator with the coaxial ceramic capacitor had better characteristics than the one that used three plate ceramic capacitors with a rise time of 630-860 ps when the peak output voltage was in the range of 5-30 kV.

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Shrubs are the major components of vegetation in arid and semi-arid areas, and play a pivotal role in maintaining ecosystem stability and function. The nurse effects of shrubs can help with the regeneration of native target plant species by alleviating the adverse influences that limit their growth and reproduction in degraded habitats. We summarized the main research results and application of shrub nurse effects in the last 20 years. We discussed several facilitation mechanisms of nurse shrubs, including microhabitat amelioration, fertile island formation, defense and resistance against herbivores, introduction of beneficial microorganism and propagule propagation or preservation, as well as changes in the patterns of interspecific competitive networks. Key factors affecting nurse effects were analyzed, including abiotic environments, biological disturbances, plant life history as well as growth and reproductive strategies. Prospects for future research were also considered from the aspects of improving theore-tical mechanisms of nurse effects by shrubs and building models involved in multiple plant species interaction affec-ted by multifactors.

Simulation of primary current distribution in Tesla-type pulse generators.

In a Tesla-type pulse generator, self-inductance of the primary coil is a crucial parameter to determine the final oscillating condition. However, the accurate value of this inductance might be changed due to the uneven primary current distribution caused by practical configuration of the primary side. Consequently, in order to precisely design the transformer, it is helpful to evaluate the primary inductance based on electromagnetic simulation instead of conventional approximate calculation. In this paper, a simulation model based on the finite integration technique is established to solve the uneven primary current problem. A primary coil with multiple contacting points is designed, and hexahedral mesh generation of the coil is also discussed. Hence, a series of verification tests using different primary structures are performed to support the results of simulation. Both results of the simulation model and the verification test presented that the variation of the primary inductance will affect the performance of the generator, and the number of contacting points is the main cause to determine the maximum current density of the coil.

The Short-Term Efficacy and Safety of Brentuximab Vedotin Plus Cyclophosphamide, Epirubicin and Prednisone in Untreated PTCL: A Real-World, Retrospective Study.

INTRODUCTION: Brentuximab vedotin (BV) showed high overall remission rates in refractory/relapsed classical Hodgkin's lymphoma (HL) and systemic anaplastic large cell lymphoma (sALCL). Although the efficacy of BV has been reported in clinical trials, its efficacy as a frontline therapy in real world for patients with CD30 positive subtypes of non-Hodgkin's lymphoma (NHL) such as peripheral T-cell lymphoma with T-follicular helper cell (TFH) phenotype (PTCL, TFH), anaplastic large-cell lymphoma (ALCL) and angioimmunoblastic T-cell lymphoma (AITL) in China has not been well documented. METHODS: Analysis of a real-world, observational, retrospective case series in patients suffering from AITL, sALCL and peripheral T-cell lymphoma with T-follicular helper phenotype (PTCL-TFH) and other types of PTCL treated with BV in frontline treatment was conducted. The patients were given treatment from May 2020 till June 28, 2021. All patients were pathologically diagnosed to have PTCL before treatment and expressed CD30. Patients received BV (1.8 mg/kg) combined with CEP (cyclophosphamide, epirubicin, prednisone acetate every 3 weeks). The primary endpoint was objective response rates (ORR), and secondary endpoints were duration of response and incidence of adverse events (AEs). Exploratory endpoints such as progression-free survival (PFS) are discussed even though after such a short period. RESULTS: Nineteen patients completed ≥ 1 cycles of BV-CEP treatment (16 cases completed ≥ 4 cycles, 3 cases only completed 1 cycle). Among them, the ORR reached 89.5% [CR 52.7%; partial response (PR) 36.8%]. In the ALCL group, CR reached 100% with the median duration of response of up to 8 months, while in the AITL group, the ORR was 75% and 2 patients had disease progression after treatment with BV + CEP. We also observed that BV-CEP may extend the PFS compared to traditional chemotherapy such as the CHOEP regimen (BV-CEP: not evaluable, CHOEP: 6.5 months), although the median follow-up was only 6.7 months. Adverse events (AEs), including incidence and severity of febrile neutropenia (26% patients in the BV-CEP group and 30% in the CHOEP group), were similar between groups. There was no incidence of AEs leading to treatment withdrawal or death under BV-CEP treatment. CONCLUSION: BV is a promising treatment in patients with ALCL, AITL and PTCL-TFH in frontline treatment settings.

Generation and manipulation of ultrahigh order plasmon resonances in visible and near-infrared region.

Optical properties of periodic nanorings with built-in V-shaped nanowedges (NRBV) are investigated theoretically. Tunable ultrahigh order Fano resonances are achieved and they are found to be sensitive to geometric parameters and surrounding dielectric environment of the planar nanostructure. High order Fano resonances can be suppressed or enhanced by adjusting the opening angle of the nanowedge, the size of the nanoring and the aspect ratio of the nanowedge. Moreover, manipulating the offset of the built-in nanowedge, or filling dielectrics asymmetrically can revive suppressed Fano resonances when the V-shaped nanowedge develops into a straight nanorod. Meanwhile, stronger plasmon resonances emerge alternately in the two parts of this planar nanostructure. This periodic plasmonic nanostructure produces ultrahigh order plasmon resonances and stronger electric field enhancement, which have great potential applications in multi-wavelength surface enhanced spectroscopy and biochemical sensing.

A 800 kV compact peaking capacitor for nanosecond generator.

An extremely compact high voltage peaking capacitor is developed. The capacitor has a pancake structure with a diameter of 315 mm, a thickness of 59 mm, and a mass of 6.1 kg. The novel structural design endows the capacitor with a better mechanical stability and reliability under hundreds of kilovolts pulse voltage and an inner gas pressure of more than 1.5 MPa. The theoretical value of the capacitor self-inductance is near to 17 nH. Proved by series of electrical experiments, the capacitor can endure a high-voltage pulse with a rise time of about 20 ns, a half-width duration of around 25 ns, and an amplitude of up to 800 kV in a single shot model. When the capacitor was used in an electromagnetic pulse simulator as a peaking capacitor, the rise time of the voltage pulse can be reduced from 20 ns to less than 3 ns. The practical value of the capacitor's inductance deduced from the experimental date is no more than 25 nH.

Self-assembly of amido-ended hyperbranched polyester films with a highly ordered dendritic structure.

Self-assemblies fabricated from dendrimers and amphiphilic polymers have demonstrated remarkable performances and a wide range of applications. Direct self-assembly of hyperbranched polymers into highly ordered macrostructures with heat-resistance remains a big challenge due to the weak amphiphilicity of the polymers. Here, we report the self-assembly of amphiphilic amido-ended hyperbranched polyester (HTDA-2) into millimeter-size dendritic films using combined hydrogen bond interaction and solvent induction. The self-assembly process and mechanism have been studied. Hydrogen bond interaction between amido-ended groups assists the aggregation of inner and outer chains of the HTDA-2, resulting in phase separation and micelle formation. Some micelles attach to and grow on the glass substrate like seedlings. Other micelles move to the seedlings and connect with their branches via solvent induction and hydrogen bond interaction, leading to the fabrication of highly ordered crystalline dendritic films that show high heat-resistance. HTDA-2 can further self-assemble into sheet crystals on the dendritic films.

Facile fabrication and upconversion luminescence enhancement of LaF3:Yb3+/Ln3+@SiO2 (Ln = Er, Tm) nanostructures decorated with Ag nanoparticles.

A novel hybrid nanostructure, that is a Ag nanoparticle decorated LaF(3):Yb(3+)/Ln(3+)@SiO(2) nanosphere (Ln=Er, Tm), was constructed by a facile strategy, and characterized by XRD, TEM, FTIR, XPS and UV-vis-NIR absorption. Obvious spectral broadening and red-shift on the surface plasmon resonance were obtained by adjusting the size and configuration of Ag nanoparticles. Effective upconversion luminescence enhancements for Er(3+) and Tm(3+) containing samples were obtained. It is suggested that the luminescence enhancement results from both the excitation and emission processes, and the configuration of the studied hybrid nanostructure is an efficient system to enhance the luminescence emission of rare earth doped nanomaterials. It is believed that the enhancement from the hybrid nanostructure will find great potential in the development of photovoltaic solar cells.

Chronic alcohol consumption induces cardiac remodeling in mice from Th1 or Th2 background.

AIMS: The effects of T helper (Th) cells on alcoholic cardiomyopathy have not been extensively investigated. Strain of mice with Th1 or Th2 immunological background were utilized in this study in order to explore the role of Th1/Th2 in chronic alcohol-induced cardiac fibrosis. METHODS AND RESULTS: C57BL/6 WT or Balb/c mice were treated with alcohol for 90 days. Then cardiac structure and function were analyzed via echocardiography. Spleen CD4+CD25+Foxp3+ Tregs were determined by flow cytometry. The hearts were stained using haematoxylin and eosin (HE) and Masson's trichome. Myocardial ultrastructure was observed by electron microscopy. Expression of T-bet, GATA-3, IL-4 and IFN-gamma were determined by real-time RT-PCR. The heart was dilated significantly in the C57BL/6 WT+alcohol group and Balb/c+alcohol group compared with the controls. CD4+CD25+Foxp3+ Tregs were not statistically different. Masson's trichome staining revealed that fibrosis was more pronounced in the alcohol treated groups than the controls. Fibrosis was more evident in the Balb/c+alcohol group compared to the C57BL/6 WT+alcohol group. Alcohol consumption caused a decrease in the Th1 polarization and an increase in the Th2 response. CONCLUSIONS: Chronic alcohol consumption induced a Th2 response within the Th1/Th2 balance. Th2 response is one of the underlying mechanism involved in alcohol-induced cardiac fibrosis.