Validation of the plasma-wall self-organization model for density limit in ECRH-assisted start-up of Ohmic discharges on J-TEXT

A recently developed plasma-wall self-organization (PWSO) model predicts a significantly enhanced density limit, which may be attainable in tokamaks with ECRH-assisted ohmic startup and sufficiently high initial neutral density. Experiments have been conducted on J-TEXT to validate such a density limit scenario based on this model. Experimental results demonstrate that increasing the pre-filled gas pressure or ECRH power during the startup phase can effectively enhance plasma purity and raise the density limit at the flat-top. Despite the dominant carbon fraction in the wall material, some discharges approach the edge of the density-free regime of the 1D model of PWSO.Comment: 17 pages, 8 figure

Critical roles of edge turbulent transport in the formation of high-field-side high-density front and density limit disruption in J-TEXT tokamak

This article presents an in-depth study of the sequence of events leading to density limit disruption in J-TEXT tokamak plasmas, with an emphasis on boudary turbulent transport and the high-field-side high-density (HFSHD) front. These phenomena were extensively investigated by using Langmuir probe and Polarimeter-interferometer diagnostics

Immunogenicity and safety of an inactivated enterovirus 71 vaccine coadministered with trivalent split-virion inactivated influenza vaccine: A phase 4, multicenter, randomized, controlled trial in China

BackgroundFew data exist on the immunogenicity and safety of an inactivated enterovirus 71 vaccine (EV71 vaccine) coadministered with trivalent split-virion inactivated influenza vaccine (IIV3) in infants.MethodsThis trial was a phase 4, randomized, controlled trial. Infants aged 6-11 months were eligible, with no history of hand, foot and mouth disease (HFMD) and no history of EV71 vaccine or any influenza vaccine. Eligible infants were randomly assigned to EV71+IIV3 group, EV71 group or IIV3 group. Blood samples were collected on day 0 and 56.ResultsBetween September 2019 and June 2020, 1151 infants met eligibility criteria and 1134 infants were enrolled. 1045 infants were included in the per-protocol population, including 347 in the EV71+IIV3 group, 343 in the EV71 group, and 355 in the IIV3 group. The seroconversion rate (98.56% vs 98.54%; seroconversion rates difference of 0.02% [95% CI: 0.70-0.98]) and GMT (419.05 vs 503.72; GMT ratio of 0.83 [95% CI 0.70 - 0.98]) of EV71 neutralizing antibodies in the EV71+IIV3 group was not inferior to those in the EV71 group. The non-inferiority results for influenza virus antibodies (A/H1N1, A/H3N2 and B) showed that the seroconversion rates and GMTs of the EV71+IIV3 group were non-inferiority to those of the IIV3 group. Systemic and local adverse event rates were similar between groups. None of serious adverse events (SAEs) were related to vaccination.ConclusionsCoadministration of the EV71 vaccine with IIV3 was safe and did not interfere with immunogenicity. These findings support a viable immunization strategy for infants with the EV71 vaccine coadministered with IIV3 in China. This trial is registered with ClinicalTrials.gov, number NCT04091880

The \u3cem\u3eChlamydomonas\u3c/em\u3e Genome Reveals the Evolution of Key Animal and Plant Functions

Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It is a model system for studying chloroplast-based photosynthesis, as well as the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited from the common ancestor of plants and animals, but lost in land plants. We sequenced the ∼120-megabase nuclear genome of Chlamydomonas and performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated with the function and biogenesis of chloroplasts or eukaryotic flagella. Analyses of the Chlamydomonas genome advance our understanding of the ancestral eukaryotic cell, reveal previously unknown genes associated with photosynthetic and flagellar functions, and establish links between ciliopathy and the composition and function of flagella

Novel Tunable Green-Red Luminescence in Mn2+ Doped Ca9Tb(PO4)7 Phosphors Based on the Mn2+ Regulation and Energy Transfer

β-Ca3(PO4)2 type phosphors Ca9Tb(PO4)7:Mn2+ were fabricated by high temperature solid state reaction. Under 377 nm light excitation, the Ca9Tb(PO4)7 host displays the green emission attributable to the characteristic emission of Tb3+ ions peaking at 488, 542, 586, and 620 nm, respectively. The red broadband emission is observed when Ca9Tb(PO4)7 is doped with Mn2+ ions. The emission is attributed to the energy transfer from Tb3+ to Mn2+ ions; this facilitates the realization of the tunable green–red emission. The energy transfer mechanism from Tb3+ to Mn2+ is defined as quadrupole–quadrupole interaction. Furthermore, the thermal stability of Ca9Tb(PO4)7:Mn2+ samples has been studied, and it can maintain half the emission intensity exceeding 424 K. This demonstrates their potential applications in white light LEDs (w-LEDs)

A Compact Aperture-Sharing Sub-6 GHz/Millimeter-Wave Dual-Band Antenna

In this article, a microwave (MW)/millimeter wave (MMW) aperture-sharing antenna is proposed. The antenna is constructed using two orthogonal columns of grounded vias from a 3.5 GHz slot-loaded half-mode substrate-integrated waveguide (HMSIW) antenna. These vias are reused to create two sets of 1 × 4 MMW substrate-integrated dielectric resonator antenna (SIDRA) arrays. With this proposed partial structure reuse strategy, the MW antenna and MMW arrays can be integrated in a shared-aperture manner, improving space utilization and enabling dual-polarized beam steering capability in the MMW band, which is highly desirable for multiple-input multipleoutput (MIMO) applications. The integrated antenna prototype was manufactured and measured for verification. The 3.5 GHz antenna has a relative bandwidth of 3.4% (3.44–3.56 GHz) with a peak antenna gain of 5.34 dBi, and the 28 GHz antenna arrays cover the frequency range of 26.5–29.8 GHz (11.8%) and attain a measured peak antenna gain of 11.0 dBi. Specifically, the 28 GHz antenna arrays can realize dual-polarization and ±45° beam steering capability. The dual-band antenna has a very compact structure, and it is applicable for 5G mobile communication terminals

Aerobic Oxidation of Benzyl Alcohol over Activated Carbon Supported Manganese and Vanadium Catalysts: Effect of Surface Oxygen-Containing Groups

In this contribution, the selective oxidation of benzyl alcohol using molecular oxygen over supported manganese and vanadium catalysts was investigated. The catalytic activities were significantly improved after pre-oxidizing the activated carbon support materials. Characterizations of nitrogen physisorption, X-ray diffraction, transmission electron microscopy, and X-ray absorption were involved to examine the physicochemical properties of as-prepared catalysts. By ruling out the effects of specific surface area, active site dispersion, valence and local coordination of Mn and V active species, the improved catalytic activity was attributed to the specific variety and increased density of oxygen-containing groups on activated carbon support surfaces, which was further confirmed by cyclic voltammetry measurements and Fourier transform infrared spectroscopy

Spatial pattern of soil erodibility factor (K) as affected by ecological restoration in a typical degraded watershed of central China

Long-term ecological restoration of degraded habitats can alter their near-land surface characteristics and thus affect soil erodibility factor (K). In this study, we used geostatistics coupled with structural equation modeling (SEM) to investigate the spatial patterns of K and quantify its relationship to potential impact factors (spatial location, topography, plant, and soil characteristics) in a restored watershed in the Danjiangkou Reservoir region of central China. Results showed that the K values in this watershed ranged from 0.026 Mg h Mj(-1) mm(-1) to 0.057 Mg h Mj(-1) mm(-1) land generally increased with soil depth. Across the watershed, the K values in the surface soil (0-10 cm) were the highest in the mid-stream region, followed by the downstream and upstream regions. No obvious pattern in the relationship between K and the slope was found in either the 0-10 cm Of 10-30 cm soil layer. Among the four land-use types, the K values followed the rank of shrubland > terrace and slope farmland > woodland. SEM results indicated that the variation in Kin this restored watershed was closely related to soil texture and soil organic matter (SOM) content. The external environmental variables (spatial location, topography, and plant) significantly influenced indirectly soil erodibility through their effects on the intrinsic soil characteristics (particularly the SOM) at both depths (R-2 of 0.67 and 0.33, respectively). Although soil texture was shown to be an important direct-effect factor (with path coefficients of 0.72 and 0.90, respectively), its external interpretation was the weakest among all the direct-effect factors (R-2 of 0.12 and 0.02, respectively). These results showed that afforestation, increasing soil organic fertility, and reducing tillage should be promoted in the future. (C) 2020 Elsevier B.V. All rights reserved

Effects of Heat Addition on Wave Drag Reduction of a Spiked Blunt Body

Drag reduction technology plays a significant role in extending the flight range for a high-speed vehicle. A wave drag reduction strategy via heat addition to a blunt body with a spike was proposed and numerically validated. The heat addition is simulated with continuous heating in a confined area upstream of the blunt body. The effects of heat addition on drag reduction in three flow conditions (M=3.98,5,6) were compared, and the influence of power density qh (q1=2.0×108 W/m3, q2=5.0×108 W/m3, and q3=1.0×109 W/m3) of heating was evaluated. Results show that the heat addition has a positive way to reduce the drag of the body with a spike alone, and more satisfactory drag reduction effectiveness can be achieved at a higher Mach number. The drag reduction coefficient increases with qh in the same flow condition, with a maximum of 38.9% (M=6) as q3=1.0×109 W/m3. The wave drag reduction principle was discussed by a transient calculation, which indicates that the separation region has entrainment of the heated air and expanded with its sonic line away from the blunt cone, which results in an alleviation of the pressure load caused by shock/shock interaction