基于OBE理念的有机化学混合“五式”教学法的设计与实施

为解决有机化学课程教学过程中遇到的实际问题,探索因材施教的个性化培养模式,引导学生不断提升学习的主动性和解决实际问题的能力,我们基于OBE(Outcome based education)教育理念,结合中国科学技术大学有机化学课程目标和学习效果金字塔,以学生学为中心,以成果为导向,精心设计了引导式预习、精准式授课、互助式讨论、示范式点评和全程式考核的线上线下混合“五式”教学法,在实际教学运用中取得了良好成效,达到了预期目标。

Molecular Epidemiological Study of a Human Brucellosis Outbreak—Weihai City,Shandong Province,China,2022

What is already known about this topic?Brucellosis,mainly caused by Brucella melitensis(B.melitensis),is regarded as a significant zoonotic disease in China.In Weihai,located at the eastern end of the Shandong Peninsula,brucellosis has been in a low epidemic phase for the past five years.What is added by this report?This was the initial report of a brucellosis outbreak in the last five years.Strains of B.melitensis bv.3 from Weihai and other cities showed a close genetic relationship,suggesting a potential common ancestry.What are the implications for public health practice?Epidemiological investigations depend on standardized and effective molecular typing methods and analysis tools for public health laboratories to identify and trace outbreaks.Understanding the circulation patterns of livestock in free-range households in heavily affected areas is essential for controlling the spread of brucellosis.

Triazole backbone ligand in an unprecedented efficient manganese catalyst for use in transfer hydrogenation

Noble metal catalysts are generally expensive,and thus,abundant 3d metals recently received significant attention as catalysts in catalytic hydrogenation.Mn catalysts are widely applied in transfer hydrogenations,but the reported catalyst loadings remain up to three orders of magnitude higher than noble metals.Thus,catalyst consumption should be overcome before 3d metal catalytic systems may be utilized practically in industry.Here,a catalytic system based on novel,scalable triazole N5-ligands coordinated to Mn is presented for use in transfer hydrogenations.Based on pre-activation via dehydrohalogenation,an unprecedented,efficient catalytic system operating via synergistic H-bond auxiliary activation was established.The Mn catalysts are practical at metal concentrations 0.0001 mol%,generating alcohol with turnover number(TON)up to 857,200,thus approaching loadings more conventionally observed in precious-metal-based systems.Notably,using this protocol,several pharmaceuticals may be easily synthesized in one pot.

Express,on of the novel adipokine ClqTNF-related protein 4 （CTRP4） suppresses colitis and colitis- associated colorectal cancer in mice

Inflammatory bowel disease （IBD） is an important factor in the induction of colon cancer, but its mechanism is unclear. Colitis and colitis-associated colorectal cancer （CAC） models induced using both dextran sulfate sodium （DSS） and the azoxymethane/DSS protocol were established in wild-type （WT） and CTRP4 transgenic （CTRP4-tg） C57BL6/J mice. Body weight, stool consistency and the presence of blood in the stool were analyzed; tumor quantity, size and histological characteristics were analyzed during the development of CAC. The CTRP4-tg mice exhibited significantly reduced colitis and developed far fewer macroscopic tumors; these tumors were smaller in size, and a majority of the colon tumors in these mice were restricted to the superficial mucosa. Tumors of lower grades were observed in the CTRP4-tg mice. Interleukin-6 was markedly downregulated in the CTRP4-tg mice during CAC tumorigenesis. The phosphorylation of ERK, signal transducer and activator of transcription 3 and Akt in the colon and the proliferation of intestinal epithelial cells were decreased in the CTRP4-tg mice. The injection of recombinant CTRP4 protein significantly reduced the colitis symptoms of the WT mice. CTRP4 plays an important role in inflammation and inflammation-associated colon tumorigenesis, and our research may provide a novel method for the treatment of IBD and CAC.

N-doped honeycomb-like porous carbon towards high-performance supercapacitor

Biomass-derived porous carbon with developed pore structure is critical to achieving high performance electrode materials.In this work,we report a grape-based honeycomb-like porous carbon(GHPC)prepared by KOH activation and carbonization,followed by N-doping(NGHPC).The obtained NGHPC exhibits a unique honeycomb-like structure with hierarchically interconnected micro/mesopores,and high specific surface area of 1268 m^2/g.As a supercapacitor electrode,the NGPHC electrode exhibits a remarkable specific capacitance of 275 F/g at 0.5 A/g in a three-electrode cell.Moreover,the NGHPC//NGHPC symmetric supercapacitor displays a high energy density of 12.6 Wh/kg,and excellent cycling stability of approximately 95.2% capacitance retention after 5000 cycles at 5 A/g.The excellent electrochemical performance of NGHPC is ascribed to its high specific surface area,honeycomb-like structure and high-content of pyrodinic-N(36.29%).It is believed that grape-based carbon materials show great potential as advanced electrode materials for supercapacitors.

Precipitation of Ti 2 Al phases at lamellar interfaces in a high-Nb-containing TiAl alloy during thermal exposure

The thermal stability of microstructures is crucial for determining the performance of alloys in extreme environments.In the present work,the microstructural evolution and precipitation behavior in a high Nb-containing Ti45Al8Nb alloy during thermal exposure at 950°C were investigated.It was found that excessα2 phases in the as-cast microstructure were unstable and tended to decompose during thermal expo-sure.Hexagonal Ti 2 Al phases precipitated at lamellar interfaces and had a[1¯10]_(γ)[11¯20]_(α2)[11¯20]_(Ti2Al),(002)_(γ)(1¯100)_(α2)(1¯100)_(Ti2Al)crystallographic orientation relationship(OR)with the matrix.Stacking faults(SFs)generated inα2 phases during theα2→γphase transformation provided favorable nucleation sites for Ti 2 Al phases.