Research Progress of Agricultural Genetically Modified Crop Safety Evaluation

The commercial cultivation of genetically modified(GM)crops has eased the global food crisis and brought considerable economic and social benefits to countries.Because of the potential safety problems,it is necessary to make clear the molecular genetic characteristics,edible safety,planting,processing,and other aspects of the safety evaluation of GM crops.The safety problems existing in the cultivation of GM crops,safety evaluation and detection of GM crops were introduced in this paper,which provided the basis for safety evaluation and effective supervision of GM crops and their products.Commercial cultivation and reasonable supervision based on safety evaluation have far-reaching significance for ensuring consumer safety,enhancing the credibility of the national political system and enhancing citizens'confidence in the safety of GM crop products for consumption.

Neglected Aspects of SARS-CoV-2 Aerosol Transmission in Bathrooms of Multistory and High-Rise Buildings—Beijing Municipality,China,October 2022

Summary What is already known about this topic?There is a toilet flush-soil stack-floor drain pathway of aerosol transmission in multistory and high-rise buildings,but the influencing factors are not completely clear.What is added by this report?The poor airtightness of the connecting parts of the floor drain,as well as pressure fluctuations in the sewage pipe during toilet flushing caused by blockage of the soil stack vent,may lead to the cross-floor transmission of viral aerosols through the soil stack and floor drains.

Green hydrogen production by intermediate-temperature protonic solid oxide electrolysis cells:Advances,challenges,and perspectives

Protonic solid oxide electrolysis cells(P-SOECs)operating at intermediate temperatures,which have low costs,low environmental impact,and high theoretical electrolysis efficiency,are considered promising next-generation energy conversion devices for green hydrogen production.However,the developments and applications of P-SOECs are restricted by numerous material-and interface-related issues,including carrier mismatch between the anode and electrolyte,current leakage in the electrolyte,poor interfacial contact,and chemical stability.Over the past few decades,considerable attempts have been made to address these issues by improving the properties of P-SOECs.This review comprehensively explores the recent advances in the mechanisms governing steam electrolysis in P-SOECs,optimization strategies,specially designed components,electrochemical performance,and durability.In particular,given that the lack of suitable anode materials has significantly impeded P-SOEC development,the relationships between the transferred carriers and the cell performance,reaction models,and surface decoration approaches are meticulously probed.Finally,the challenges hindering P-SOEC development are discussed and recommendations for future research directions,including theoretical calculations and simulations,structural modification approaches,and large-scale single-cell fabrication,are proposed to stimulate research on P-SOECs and thereby realize efficient electricity-to-hydrogen conversion.

O-glycosyltransferases from Homo sapiens contributes to the biosynthesis of Glycyrrhetic Acid 3-O-mono-β-D-glucuronide and Glycyrrhizin in Saccharomyces cerevisiae

Glycyrrhizin(GL)and Glycyrrhetic Acid 3-O-mono-β-D-glucuronide(GAMG)are the typical triterpenoid glycosides found in the root of licorice,a popular medicinal plant that exhibits diverse physiological effects and pharmacological manifestations.However,only few reports are available on the glycosylation enzymes involved in the biosynthesis of these valuable compounds with low conversion yield so far.In mammals,glycosyltransferases are involved in the phase II metabolism and may provide new solutions for us to engineer microbial strains to produce high valued compounds due to the substrate promiscuity of these glycosyltransferases.In this study,we mined the genomic databases of mammals and evaluated 22 candidate genes of O-glycosyltransferases by analyzing their catalytic potential for O-glycosylation of the native substrate,glycyrrhetinic acid(GA)for its glycodiversification.Out of 22 selected glycosyltransferases,only UGT1A1 exhibited high catalytic performance for biosynthesis of the key licorice compounds GL and GAMG.Molecular docking results proposed that the enzymatic activity of UGT1A1 was likely owing to the stable hydrogen bonding interactions and favorite conformations between the amino acid residues around substrate channels(P82~R85)and substrates.Furthermore,the complete biosynthesis pathway of GL was reconstructed in Saccharomyces cerevisiae for the first time,resulting in the production of 5.98±0.47 mg/L and 2.31±0.21 mg/L of GL and GAMG,respectively.

Filtration efficiency of face masks against aerosolized surrogate SARS-CoV-2 at different social distances

The coronavirus disease 2019(COVID-19)pandemic is an unpreedented global event.It has become clear that COVID-19 is transmitted by virus-containing droplets(>5μm)and aerosols(<5μm),and that all human exhalatory activities(e.g.,breathing,speaking,singing,shouting,coughing,and sneezing)result in the emission of suspended droplets/aerosols of various sizes.As an example,COVID-19 patients exhale millions of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)RNA copies into the air per hour[1].SARS-CoV-2-laden aerosols play a profound role in disease transmission,as they can linger and remain viable in the air for a long duration(~16 h)[2]and travel a long distance(~4.8 m)due to their smaller size[3].

SARS-CoV-2 Aerosol Transmission Through Vertical Sanitary Drains in High-Rise Buildings--Shenzhen,Guangdong Province,China,March 2022

Summary What is already known about this topic?Aerosol transmission of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)via sanitary pipelines in high-rise buildings is possible,however,there is a lack of experimental evidence.