有机化学课程人物思政元素教学融入方法探索——以邮票上的“吉森学派”为例

化学人物的教学融入是有机化学课程思政教学过程中的重要组成部分和必不可少的环节。化学主题邮票作为一类特色的教学资源和载体,蕴含着丰富的思政育人内容。本文针对农学类有机化学课程开展了以“吉森学派”化学人物主题邮票为主线之一的大学化学教学实践。对化学主题邮票应用于教学的简要历史、可行性和意义加以分析,并对化学人物主题邮票这一特色载体融入教学的方法、效果和反思进行总结,旨在为此类教学开展提供参考。

Scaly-sided Merganser(Mergus squamatus)equalizes foraging costs with depth by switching foraging tactics

Throughout evolutionary history,animals are finely tuned to adjust their behaviors corresponding to environmental variations.Behavioral flexibility represents an important component of a species'adaptive capacity in the face of rapid anthropogenetic environmental change,and knowledge of animal behaviors is increasingly recognized in conservation biology.In aquatic ecosystem,variation of water depth is a key factor affecting the availability of food;thus,the foraging behaviors of many waterbirds,especially piscivores.In this study,we compared the foraging behaviors of the Scaly-sided Merganser(Mergus squamatus),an endangered migratory diving duck endemic to East Asia,in habitats with different water depths(Shallow waters:0–40 cm;Deep waters:40–300 cm),using video camera records obtained from the known wintering sites during three winters from 2018 to 2020.Further,the energy expenditure of foraging behavior profile and energy intake based on fish sizes were calculated to study the foraging energetics.In total,200 effective video footages that contained 1086 min with 17,995 behaviors and 163 events of catching fish were recorded.Results showed that:1)time length for fishing(including eye-submerging,head-dipping,diving and food handling)of M.squamatus in shallow waters was significantly more than in deep waters;2)M.squamatuss spent significantly more time for preparing(including vigilance,preening and swimming)in deep waters than in shallow waters;3)the mean catch rate was 0.28 fish/min in shallow waters,which is significantly higher than the value of 0.13 fish/min in deep waters;4)despite the distinct foraging behavior profiles and energy intakes,M.squamatus showed similar energetics in shallow and deep waters.We concluded that M.squamatus is a good example of behavioral flexibility that aligns with expectations of optimal foraging theory,in that it behaves in accordance to resource availability in different environments,resulting in high foraging efficiency.

Antibacterial activity evaluation of a novel K3-specific phage against Acinetobacter baumannii and evidence for receptor-binding domain transfer across morphologies

Acinetobacter baumannii(A.baumannii)poses a serious public health challenge due to its notorious antimicrobial resistance,particularly carbapenem-resistant A.baumannii(CRAB).In this study,we isolated a virulent phage,named P1068,from medical wastewater capable of lysing CRAB,primarily targeting the K3 capsule type.Basic characterization showed that P1068 infected the A.baumannii ZWAb014 with an optimal MOI of 1,experienced a latent period of 10 min and maintained stability over a temperature range of 4–37C and pH range of 3–10.Phylogenetic and average nucleotide identity analyses indicate that P1068 can be classified as a novel species within the genus Obolenskvirus of the Caudoviricetes class as per the most recent virus classification released by the International Committee on Taxonomy of Viruses(ICTV).Additionally,according to classical morphological classification,P1068 is identified as a T4-like phage(Myoviridae).Interestingly,we found that the tail fiber protein(TFP)of P1068 shares 74%coverage and 88.99%identity with the TFP of a T7-like phage(Podoviridae),AbKT21phiIII(NC_048142.1).This finding suggests that the TFP gene of phages may undergo horizontal transfer across different genera and morphologies.In vitro antimicrobial assays showed that P1068 exhibited antimicrobial activity against A.baumannii in both biofilm and planktonic states.In mouse models of intraperitoneal infection,P1068 phage protected mice from A.baumannii infection and significantly reduced bacterial loads in various tissues such as the brain,blood,lung,spleen,and liver compared to controls.In conclusion,this study demonstrates that phage P1068 might be a potential candidate for the treatment of carbapenem-resistant and biofilmforming A.baumannii infections,and expands the understanding of horizontal transfer of phage TFP genes.

基于自监督的端到端图数据异常检测方法

异常检测旨在发掘数据中异于寻常的模式,它在金融欺诈以及网络入侵检测等领域有着广泛的应用前景.本文主要研究了如何在结构复杂的图数据中进行异常检测,这涉及到挖掘异常的图结构信息以及节点属性信息.现有大部分工作通常采用一个两步的框架,即先对结构复杂的图数据进行表征学习生成图表征向量,然后再将该向量用于下游异常检测任务.由于分开训练的图表征学习任务与下游异常检测任务存在一定的语义鸿沟,这导致现有方法无法有效地挖掘出图中潜在的异常模式.因此,我们提出了一种基于自监督的端到端图数据异常检测框架SGAD,它可以有效地捕获图数据的语义信息并用于异常检测.具体来说, SGAD对无标签图数据进行了一系列变换用于构建自监督辅助任务,然后该自监督任务的输出结果可以直接用于异常检测.我们在多个公开数据集上进行了大量实验,实验结果表明本文提出的SGAD与现有方法相比获得了显著的效果提升.

A Simple Synthesis of Tetraamino-[60]Fullerene Epoxides as Potential Antitumor Drug Candidates

Amphiphilic aminated fullerenes have a broad margin of safety and significant antitumor effects.Herein,we develop a simple and versatile synthesis strategy for tetraamino-[60]fullerene epoxide(C_(60)(NR^(1)R^(2))_(4)O)using C_(60)Cl_(6)as a precursor,which notably reduces the reaction time to less than 1 h while retaining a high yield of over 80%with both cyclic and linear secondary amine substrates even at the gram level.The molecular structure of C_(60)(NR^(1)R^(2))_(4)O is first validated by single-crystal diffraction,and a two-step reaction mechanism comprising nucleophilic substitution of Cl and the oxidative elimination of Cl_(2)is proposed based on experimental verification and density functional theory simulation.A set of water-soluble aminated C_(60)(NR^(1)R^(2))_(4)O was prepared in large quantities,and in vitro antitumor evaluation unveiled the critical role that terminal primary amino moieties of C_(60)(NR^(1)R^(2))_(4)O play in their antineoplastic effects.This work provides an effective synthesis method for aminated C_(60)(NR^(1)R^(2))_(4)O,facilitating the development of fullerene-derived tumor-targeted drugs.