Analysis on the Cause and Forecast Deviation of an Extreme Rainstorm in Changsha Urban Area

Using NCEP reanalysis data,high-altitude and ground observation data,numerical model data,satellite and radar data,formation cause and forecast deviation of an extreme rainstorm process in Changsha urban area at night on June 9,2020 were analyzed.The results showed that(1)the extreme rainstorm process developed near the surface convergence line,with strong localization,short duration and large hourly rainfall intensity.(2)Under the high temperature and high humidity environment,the low-level cold advection and the hot low-pressure system interacted,and the potential con-vective unstable energy was released,and a strong convective weather was formed.(3)The convergence of water vapor in the lower layer and the strong upward movement provided sufficient water vapor for the rainstorm.The low-centroid thunderstorm was the main reason for the extreme rainstorm.(4)The forecast deviation of the numerical model to the low-level shear line and the mesoscale convergence line was an important reason for the forecast deviation of the heavy rainfall area.

Effects of Environmental Factors on Corrosion Behavior of E690 Steel in Simulated Marine Environment

The effects of hydrostatic pressure, dissolved oxygen, temperature and flow velocity, and their interaction on the corrosion rates of E690 high-strength steel (HSS) in simulated marine environments were studied using response surface methodology. The results show that the flow velocity exerts the most significant influence on the corrosion rate of E690 HSS. Consequently, the corrosion behavior of E690 HSS under varying flow velocities were analyzed profoundly from initial pitting corrosion to long-term corrosion properties. The results indicate that the flow state facilitates the mass transfer and enhances the adsorption tendency of Cl− by enhancing the electrochemical activity of the steel surface. These factors accelerate the electrochemical reactions, resulting in increased pitting density, depth and the long-term corrosion rates in dynamic seawater environments.

Structure-based design of pan-coronavirus inhibitors targeting host cathepsin L and calpain-1

Respiratory disease caused by coronavirus infection remains a global health crisis.Although several SARS-CoV-2-specific vaccines and direct-acting antivirals are available,their effcacy on emerging coronaviruses in the future,including SARS-CoV-2 variants,might be compromised.Host-targeting antivirals provide preventive and therapeutic strategies to overcome resistance and manage future outbreak of emerging coronaviruses.Cathepsin L(CTSL)and calpain-1(CAPN1)are host cysteine proteases which play crucial roles in coronaviral entrance into cells and infection-related immune response.Here,two peptidomimetic a-ketoamide compounds,14a and 14b,were identified as potent dual target inhibitors against CTSL and CAPN1.The X-ray crystal structures of human CTSL and CAPN1 in complex with 14a and 14b revealed the covalent binding of a-ketoamide groups of 14a and 14b to C25 of CTSL and C115 of CAPN1.Both showed potent and broad-spectrum anticoronaviral activities in vitro,and it is worth noting that they exhibited low nanomolar potency against SARS-CoV-2 and its variants of concern(VOCs)with ECso values ranging from 0.80 to 161.7 nM in various cells.Preliminary mechanistic exploration indicated that they exhibited anticoronaviral activity through blocking viral entrance.Moreover,14a and 14b exhibited good oral pharmacokinetic properties in mice,rats and dogs,and favorable safety in mice.In addition,both 14a and 14b treatments demonstrated potent antiviral potency against SARS-CoV-2 XBB 1.16 variant infection in a K18-hACE2 transgenic mouse model.And 14b also showed effective antiviral activity against HCoV-OC43 infection in a mouse model with a final survival rate of 60%.Further evaluation showed that 14a and 14b exhibited excellent antiinflammatory effects in Raw 264.7 mouse macrophages and in mice with acute pneumonia.Taken together,these results suggested that 14a and 14b are promising drug candidates,providing novel insight into developing pan-coronavirus inhibitors with antiviral and anti-inflammatory properties.

OPPORTUNITIES AND APPROACHES FOR MANIPULATING SOIL-PLANT MICROBIOMES FOR EFFECTIVE CROP NITROGEN USE IN AGROECOSYSTEMS

Soil microbiomes drive the biogeochemical cycling of nitrogen and regulate soil N supply and loss,thus,pivotal nitrogen use efficiency(NUE).Meanwhile,there is an increasing awareness that plant associated microbiomes and soil food web interactions is vital for modulating crop productivity and N uptake.The rapid advances in modern omics-based techniques and biotechnologies make it possible to manipulate soil-plant microbiomes for improving NUE and reducing N environmental impacts.This paper summarizes current progress in research on regulating soil microbial N cycle processes for NUE improvement,plant-microbe interactions benefiting plant N uptake,and the importance of soil microbiomes in promoting soil health and crop productivity.We also proposes a potential holistic(rhizosphere-root-phyllosphere)microbe-based approach to improve NUE and reduce dependence on mineral N fertilizer in agroecosystems,toward nature-based solution for nutrient management in intensive cropping systems.

Response of bacterial communities to short-term pyrene exposure in red soil

分核，代表性的多不的芳香的烃(哼) 主要从石块燃料的不完全的燃烧生产的化合物，对生态系统健康危险。然而，长期的暴露研究没在土壤微生物上检测分核的任何重要效果。在这研究，短期的缩影实验被进行在土壤上识别分核的立即的效果细菌的社区。freshlycollected 太古的红土壤在 0， 10， 100， 200，和 500 mg