A Review of Research on Warm-Sector Heavy Rainfall in China

Warm-sector heavy rainfall (WSHR) events in China have been investigated for many years. Studies have investigated the synoptic weather conditions during WSHR formation, the categories and general features, the triggering mechanism, and structural features of mesoscale convective systems during these rainfall events. The main results of WSHR studies in recent years are summarized in this paper. However, WSHR caused by micro- to mesoscale systems often occurs abruptly and locally, making both numerical model predictions and objective forecasts difficult. Further research is needed in three areas:(1) The mechanisms controlling WSHR events need to be understood to clarify the specific effects of various factors and indicate the influences of these factors under different synoptic background circulations. This would enable an understanding of the mechanisms of formation, maintenance, and organization of the convections in WSHR events.(2) In addition to South China, WSHR events also occur during the concentrated summer precipitation in the Yangtze River-Huaihe River Valley and North China. A high spatial and temporal resolution dataset should be used to analyze the distribution and environmental conditions, and to further compare the differences and similarities of the triggering and maintenance mechanisms of WSHR events in different regions.(3) More studies of the mechanisms are required, as well as improvements to the model initial conditions and physical processes based on multi-source observations, especially the description of the triggering process and the microphysical parameterization. This will improve the numerical prediction of WSHR events.

Mesoporous SiO_(2) Sphere-Based Electrochemical Impedance Immunosensor for Ultrasensitive Detection of Bovine Interferon-γ

Interferon-γis a kind of protein with a wide range of biological activities,which can regulate the immune function of the body,and can be used as an important marker to detect and treat bovine tuberculosis diseases.Here,a picogram-level bovine interferon-γ(BoIFN-γ)electrochemical impedance immunosensor was constructed for the first time using mesoporous silica nanospheres(MS Ns)to immobilize specific monoclonal BoIFN-y antibodies.The MS Ns and BoIFN-γimmuno sensors were characterized using scanning electron microscopy,transmission electron microscope,nitrogen adsorption experiment,X-ray photoelectron spectra,and contact angle measurements.MSNs possess a substantial specific surface area and significant hydrophilicity,and can immobilize many antibody molecules,thereby improving detection sensitivity.The immunosensor has a linear detection range from 0.001 to 10.0 ng/mL with an exceptionally low detection limit of 0.62 pg/mL.Compared to the traditional BoIFN-γanalysis method,BoIFN-γimmunosensor presents superiorities in sensitivity,wide linear range as well as short processing time.More importantly,the BoIFN-γsensor exhibits high selectivity,reliable repeatability as well as stability,providing a promising application prospect for the early diagnosis of Mycobacterium bovis infection.

SAMD4 family members suppress human hepatitis B virus by directly binding to the Smaug recognition region of viral RNA

HBV infection initiates hepatitis B and promotes liver cirrhosis and hepatocellular carcinoma.IFN-α is commonly used in hepatitis B therapy,but how it inhibits HBV is not fully understood.We screened 285 human interferon-stimulated genes(ISGs)for anti-HBV activity using a cell-based assay,which revealed several anti-HBV ISGs.Among these ISGs,SAMD4A was the strongest suppressor of HBV replication.We found the binding site of SAMD4A in HBV RNA,which was a previously unidentified Smaug recognition region(SRE)sequence conserved in HBV variants.SAMD4A binds to the SRE site in viral RNA to trigger its degradation.The SAM domain in SAMD4A is critical for RNA binding and the C-terminal domain of SAMD4A is required for SAMD4A anti-HBV function.Human SAMD4B is a homolog of human SAMD4A but is not an ISG,and the murine genome encodes SAMD4.All these SAMD4 proteins suppressed HBV replication when overexpressed in vitro and in vivo.We also showed that knocking out the Samd4 gene in hepatocytes led to a higher level of HBV replication in mice and AAV-delivered SAMD4A expression reduced the virus titer in HBVproducing transgenic mice.In addition,a database analysis revealed a negative correlation between the levels of SAMD4A/B and HBV in patients.Our data suggest that SAMD4A is an important anti-HBV ISG for use in IFN therapy of hepatitis B and that the levels of SAMD4A/B expression are related to HBV sensitivity in humans.