中国古代诗词作品在分析化学酸碱滴定法教学中的应用

在分析化学课程教学中,以酸碱滴定法章节为试点,将中国古代诗词等优秀文学作品引入到酸碱滴定法概述、酸碱指示剂、酸碱滴定实验的导课、习题以及课程思政环节,旨在激发学生对分析化学课程的学习兴趣,深化对相关知识点的理解,培养学生耐心细致、严谨求实的科学态度,同时提升文化自信和人文修养。

Lymphangiogenesis contributes to exercise-induced physiological cardiac growth

Background:Promoting cardiac lymphangiogenesis exerts beneficial effects for the heart.Exercise can induce physiological cardiac growth with cardiomyocyte hypertrophy and increased proliferation markers in cardiomyocytes.However,it remains unclear whether and how lymphangiogenesis contributes to exercise-induced physiological cardiac growth.We aimed to investigate the role and mechanism of lymphangiogenesis in exercise-induced physiological cardiac growth.Methods:Adult C57 BL6/J mice were subjected to 3 weeks of swimming exercise to induce physiological cardiac growth.Oral treatment with vascular endothelial growth factor receptor 3(VEGFR3) inhibitor SAR1 3 1 675 was used to investigate whether cardiac lymphangiogenesis was required for exercise-induced physiological cardiac growth by VEGFR3 activation.Furthermore,human dermal lymphatic endothelial cell(LEC)-conditioned medium was collected to culture isolated neonatal rat cardiomyocytes to determine whether and how LECs could influence cardiomyocyte proliferation and hypertrophy.Results:Swimming exercise induced physiological cardiac growth accompanied by a remarkable increase of cardiac lymphangiogenesis as evidenced by increased density of lymphatic vessel endothelial hyaluronic acid receptor 1-positive lymphatic vessels in the heart and upregulated LYVE-1 and Podoplanin expressions levels.VEGFR3 was upregulated in the exercised heart,while VEGFR3 inhibitor SAR131675 attenuated exercise-induced physiological cardiac growth as evidenced by blunted myocardial hypertrophy and reduced proliferation marker Ki67 in cardiomyocytes,which was correlated with reduced lymphatic vessel density and downregulated LYVE-1 and Podoplanin in the heart upon exercise.Furthermore,LEC-conditioned medium promoted both hypertrophy and proliferation of cardiomyocytes and contained higher levels of insulinlike growth factor-1 and the extracellular protein Reelin,while LEC-conditioned medium from LECs treated with SAR131675 blocked these effects.Functional rescue assays further demonstrated that protein kinase B(AKT) activation,as well as reduced CCAAT enhancer-binding protein beta(C/EBPβ) and increased CBP/p300-interacting transactivators with E(glutamic acid)/D(aspartic acid)-rich-carboxylterminal domain 4(CITED4),contributed to the promotive effect of LEC-conditioned medium on cardiomyocyte hypertrophy and proliferation.Conclusion:Our findings reveal that cardiac lymphangiogenesis is required for exercise-induced physiological cardiac growth by VEGFR3 activation,and they indicate that LEC-conditioned medium promotes both physiological hypertrophy and proliferation of cardiomyocytes through AKT activation and the C/EBPβ-CITED4 axis.These results highlight the essential roles of cardiac lymphangiogenesis in exercise-induced physiological cardiac growth.

Effect of cluster needling at scalp acupoints on differential protein expression in rat brain tissue after acute focal cerebral ischemia

Objective:To explore the function of cluster needling at scalp points therapy on regulating differential protein's expression at different time points in middle cerebral artery occlusion(MCAO)model rats.Methods:Fifty-four rats were divided into three groups randomly and 18 rats in each group.The groups respectively were the model group(group M,n=18),cluster needling at scalp points group(group C,n=18),false operation group(group F,n=18).Each group was then assigned in three subgroups,including 24-h,7-day,and 14-day subgroups.Six rats in each subgroup.Acupuncture at Baihui(GV20)and 2 points beside Baihui,which was 3 e4 mm away from the midline.Longa score was used to evaluated neurological effects.Proteomics methods were used to identify differentially expression proteins with a standard of fold change greater than 1.5 and P<.05 at different times.Results:1.Nerve function scoring:The nerve function scores at 7 and 14 days decreased in group C,which showed better neural function than group M(P<.05).2.Fold change in proteins:Group M showed932 differentially expressed proteins compared with group F,and among them,414 proteins showed significant changes in expression after acupuncture.The expression levels of Cdc42 and GFAP were increased,and Mag,Shank2,and MBP levels were decreased.In the Gene Ontology analysis,the cellular component consisted of the terms cytoplasm,cytoskeleton,lysosome,and plasma membrane.The main related biological processes were cellecell signaling,protein transport,aging,and cell adhesion.Many synaptic and metabolic pathways were found by KEGG analysis.Conclusion:Cluster needling at scalp acupoints can improve the nerve function score and improve dyskinesia in MCAO model rats.Cluster needling at scalp acupoints can regulate the expression of 414 proteins,including Cdc42,GFAP,Mag,Shank2,and MBP,which are related to cerebral ischemia.The differential proteins are major concentration in cytoplasm,cytoskeleton,lysosomes,and plasma membrane,participate in cellecell signaling,protein transport,aging,and cell adhesion,and act through multiple synaptic and metabolic pathways to exert their biological functions.

Copper ion/gallic acid MOFs-laden adhesive pomelo peel sponge effectively treats biofilm-infected skin wounds and improves healing quality

Bacterial infection and scar formation remain primary challenges in wound healing.To address these issues,we developed a decellularized pomelo peel(DPP)functionalized with an adhesive PVA-TSPBA hydrogel and antibacterial gallic acid/copper MOFs.The hybrid wound dressing demonstrates favorable biocompatibility.It does not impede the proliferation of fibroblasts or immune cells and can stimulate fibroblast migration,endothelial angiogenesis,and M2 macrophage polarization.Additionally,the dressing can scavenge reactive oxygen species(ROS)and provide antioxidant effects.Furthermore,DPP+MOF@Gel effectively inhibits the viability of S.aureus and E.coli in vitro and in vivo.The histological observations revealed enhanced granulation tissue formation,re-epithelialization,and angiogenesis in the DPP+MOF@Gel group compared to other groups.The local immune response also shifted from a pro-inflammatory to a pro-regenerative status with DPP+MOF@Gel treatment.The skin incision stitching experiment further exhibits DPP+MOF@Gel could reduce scar formation during wound healing.Taken together,the hybrid DPP+MOF@Gel holds great promise for treating bacteria-infected skin wounds and inhibiting scar formation during wound healing.

Influence of surface acidity and chemical valence on low temperature activity over Pt-HSiW/CeO_(2) for catalytic combustion of chlorobenzene

Pt-HSiW/CeO_(2) catalysts were prepared for chlorobenzene(CB) catalytic combustion by hydrothermal method at different calcination temperatures,and the effects of the surface acidity and chemical valence on the catalytic activity were investigated.The results show that the catalyst calcined at 450℃(Cat-B)exhibits the outstanding catalytic performance,and the Cat-B catalyst possesses 90% conversion of CB at148℃.The excellent catalytic activity of Cat-B is attributed to more Ce^(3+)/(Ce^(3+)+Ce^(4+)),Pt~0/(Pt^(0)+Pt^(2+)),O_(ads)/(O_(latt)+O_(ads)) and Lewis acid sites.The degradation mechanism is proposed based on the analysis of the intermediates with the following reaction pathway:chlorobenzene→phenates/benzoquinone→acetate→maleate→CO_(2)+H_(2)O.

Orthogonally woven 3D nanofiber scaffolds promote rapid soft tissue regeneration by enhancing bidirectional cell migration

Repairing large-area soft tissue defects caused by traumas is a major surgical challenge.Developing multifunctional scaffolds with suitable scalability and favorable cellular response is crucial for soft tissue regeneration.In this study,we developed an orthogonally woven three-dimensional(3D)nanofiber scaffold combining electrospinning,weaving,and modified gas-foaming technology.The developed orthogonally woven 3D nanofiber scaffold had a modular design and controlled fiber alignment.In vitro,the orthogonally woven 3D nanofiber scaffold exhibited adjustable mechanical properties,good cell compatibility,and easy drug loading.In vivo,for one thing,the implantation of an orthogonally woven 3D nanofiber scaffold in a full abdominal wall defect model demonstrated that extensive granulation tissue formation with enough mechanical strength could promote recovery of abdominal wall defects while reducing intestinal adhesion.Another result of diabetic wound repair experiments suggested that orthogonally woven 3D nanofiber scaffolds had a higher wound healing ratio,granulation tissue formation,collagen deposition,and re-epithelialization.Taken together,this novel orthogonally woven 3D nanofiber scaffold may provide a promising and effective approach for optimal soft tissue regeneration.

Catalytic oxidation of toluene by manganese oxides:Effect of K^(+)doping on oxygen vacancy

Alkali metal potassium was beneficial to the electronic regulation and structural stability of transition metal oxides.Herein,K ions were introduced into manganese oxides by different methods to improve the degradation efficiency of toluene.The results of activity experiments indicated that KMnO_(4)-HT(HT:Hydrothermal method)exhibited outstanding low-temperature catalytic activity,and 90%conversion of toluene can be achieved at 243℃,which was 41℃and 43℃lower than that of KNO_(3)-HT and Mn-HT,respectively.The largest specific surface area was observed on KMnO_(4)-HT,facilitating the adsorption of toluene.The formation of cryptomelane structure over KMnO_(4)-HT could contribute to higher content of Mn^(3+)and lattice oxygen(Olatt),excellent low-temperature reducibility,and high oxygen mobility,which could increase the catalytic performance.Furthermore,two distinct degradation pathways were inferred.PathwayⅠ(KMnO_(4)-HT):toluene→benzyl→benzoic acid→carbonate→CO_(2)and H2O;PathwayⅡ(Mn-HT):toluene→benzyl alcohol→benzoic acid→phenol→maleic anhydride→CO_(2)and H2O.Fewer intermediates were detected on KMnO_(4)-HT,indicating its stronger oxidation capacity of toluene,which was originated from the doping of K^(+)and the interaction between K-O-Mn.More intermediates were observed on Mn-HT,which can be attributed to the weaker oxidation ability of pure Mn.The results indicated that the doping of K^(+)can improve the catalytic oxidation capacity of toluene,resulting in promoted degradation of intermediates during the oxidation of toluene.

文理兼收医学类专业大学化学课程教学创新与实践

大学化学是医学类专业本科生必修的公共基础课,对夯实专业基础、培养科学思维、提高综合素质具有非常重要的作用。文理兼收专业大学化学教学面临学生基础差异大、自主学习能力偏弱、课程内容较庞杂、与专业结合不强等挑战。秉承以生为本教学理念,课程创新教学设计与实践:引入分类分班教学、精炼内容、巧用案例;发展读书会、导图展、作业谈等课堂微活动;创设双师、科学评价增强课程专业特色和课堂张力。上述举措有利于提高课程的科学性、专业性和趣味性,对高质量准新医科人才的培养具有积极意义。

Effects of silver nanoparticles with different dosing regimens and exposure media on artificial ecosystem

Due to the wide use of silver nanoparticles(AgNPs) in various fields, it is crucial to explore the potential negative impacts on the aquatic environment of AgNPs entering into the environment in different ways. In this study, comparative experiments were conducted to investigate the toxicological impacts of polyvinylpyrrolidone-coated silver nanoparticles(PVP-AgNPs) with two kinds of dosing regimens, continuous and one-time pulsed dosing, in different exposure media(deionized water and XiangJiang River water). There were a number of quite different experimental results(including 100% mortality of zebrafish,decline in the activity of enzymes, and lowest number and length of adventitious roots) in the one-time pulsed dosing regimen at high PVP-AgNP concentration exposure(HOE)compared to the three other treatments. Meanwhile, we determined that the concentration of leached silver ions from PVP-AgNPs was too low to play a role in zebrafish death. Those results showed that HOE led to a range of dramatic ecosystem impacts which were more destructive than those of other treatments. Moreover, compared with the continuous dosing regimen, despite the fact that higher toxicity was observed for HOE, there was little difference in the removal of total silver from the aquatic environment for the different dosing regimens. No obvious differences in ecological impacts were observed between different water columns under low concentration exposure. Overall, this work highlighted the fact that the toxicity of Ag NPs was impacted by different dosing regimens in different exposure media, which may be helpful for assessments of ecological impacts on aquatic environments.

Activity and hydrothermal stability of CeO_2–ZrO_2–WO_3 for the selective catalytic reduction of NO_x with NH_3

A series of CeO2–ZrO2–WO3（CZW）catalysts prepared by a hydrothermal synthesis method showed excellent catalytic activity for selective catalytic reduction（SCR）of NO with NH3 over a wide temperature of 150–550℃.The effect of hydrothermal treatment of CZW catalysts on SCR activity was investigated in the presence of 10% H2O.The fresh catalyst showed above 90% NOx conversion at 201–459℃,which is applicable to diesel exhaust NOx purification（200–440℃）.The SCR activity results indicated that hydrothermal aging decreased the SCR activity of CZW at low temperatures（below 300℃）,while the activity was notably enhanced at high temperature（above 450℃）.The aged CZW catalyst（hydrothermal aging at 700℃ for 8 hr）showed almost 80% NOx conversion at 229–550℃,while the V2O5–WO3/TiO2 catalyst presented above 80% NOx conversion at 308–370℃.The effect of structural changes,acidity,and redox properties of CZW on the SCR activity was investigated.The results indicated that the excellent hydrothermal stability of CZW was mainly due to the CeO2–ZrO2 solid solution,amorphous WO3 phase and optimal acidity.In addition,the formation of WO3 clusters increased in size as the hydrothermal aging temperature increased,resulting in the collapse of structure,which could further affect the acidity and redox properties.

民间年画的当代传承与发展——以朱仙镇木版年画与高密扑灰年画为例

一、朱仙镇木版年画与高密扑灰年画发展现状比较(一)朱仙镇木版年画发展现状近几年,河南朱仙镇木版年画在国家政府、专家学者们的大力支持下,取得了一些实质性的进展。比如木版年画一条街的形成;年画展览馆的成立;年画学术论文、书籍的发表与出版等等,收效明显。并且在一些现代设计产品中,将朱仙镇木版年画作为传统文化元素融入其中,实现了传统手工艺品的现代化转型,尝试让民间传统文化融入现代人的生活。这些成效都加大了朱仙镇年画的宣传力度和传播效应,让它受到越来越多的关注与认可。