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1.
郑凌玲 《化学教育》2022,43(10):100-106
深挖高职院校公选课“生活中的化学”的育人元素,精心设计教学内容,运用课堂主题辩论、趣味生活实验的设计与展示、探秘生活中的化学等理论知识传授与课内外实践相结合的教学方式,实现全过程育人,充分展现了公选课在立德树人方面的价值。  相似文献   
2.
In this paper we consider minimizers of the functionalmin{λ1(Ω)++λk(Ω)+Λ|Ω|,:ΩD open} where DRd is a bounded open set and where 0<λ1(Ω)λk(Ω) are the first k eigenvalues on Ω of an operator in divergence form with Dirichlet boundary condition and with Hölder continuous coefficients. We prove that the optimal sets Ω have finite perimeter and that their free boundary ΩD is composed of a regular part, which is locally the graph of a C1,α-regular function, and a singular part, which is empty if d<d, discrete if d=d and of Hausdorff dimension at most dd if d>d, for some d{5,6,7}.  相似文献   
3.
CRANAD-2 is a fluorogenic curcumin derivative used for near-infrared detection and imaging in vivo of amyloid aggregates, which are involved in neurodegenerative diseases. We explore the performance of CRANAD-2 in two super-resolution imaging techniques, namely stimulated emission depletion (STED) and single-molecule localization microscopy (SMLM), with markedly different fluorophore requirements. By conveniently adapting the concentration of CRANAD-2, which transiently binds to amyloid fibrils, we show that it performs well in both techniques, achieving a resolution in the range of 45–55 nm. Correlation of SMLM with atomic force microscopy (AFM) validates the resolution of fine features in the reconstructed super-resolved image. The good performance and versatility of CRANAD-2 provides a powerful tool for near-infrared nanoscopic imaging of amyloids in vitro and in vivo.  相似文献   
4.
The health monitoring has been studied to ensure integrity of design of engine structure by detection, quantification, and prediction of damages. Early detection of faults may allow the downtime of maintenance to be rescheduled, thus preventing sudden shutdown of machines. In cylinder pressure developed, vibrations and noise emissions data provide a rich source of information about condition of engines. Monitoring of vibrations and noise emissions are novel non-intrusive methodologies for which positioning of various transducers are important issue. The presented work shows applicability of these diagnosis methodologies adopted in case of diesel engines. The effects of changing various fuel injection parameters was analyzed. Scope of using non-intrusive technique has been analyzed by changing locations of microphone. Novelty of this worklies in exploring signal processing methods for various locations around the engine test set up. Various frequency ranges of contributing noise and vibration sources were identified. Time-Frequency analysis showed the onset of various cyclic. Based on the identification of various frequency bands, it is possible to device suitable filters in order to extract more information.  相似文献   
5.
摘要:目的 比对分析 2017—2019 年北京地区实验动物微生物及遗传质量监测结果,为实验动物产业发展提供参考。 方法 按照国家和地方现行实验动物检测标准,对北京地区实验动物生产单位进行抽检,并发布检测报告。按照报告数据,对此阶段小鼠、大鼠、豚鼠、地鼠、兔、犬、猴和小型猪共 8 个品种的实验动物按照品种、等级、单位等进行分类,分析质量问题,并与 2014—2016 年同期实验动物质量比对,分析变化趋势。 结果 2017—2019 年分别抽检动物 144、131 和 135 批次,检出不合格批次分别为 30、15 和 17 批。 不合格主要因素为兔、犬及猪免疫不达标(20 批) ,病原感染 20 批,未发现遗传变异。 与 2014—2016 年同期相比,未检出遗传问题相同,免疫不达标状况好转,但病原感染出现上升。 结论 通过质量分析比对,能够为实验动物产业健康发展提供数据支持。  相似文献   
6.
Far-red emitting fluorescent labels are highly desirable for spectral multiplexing and deep tissue imaging. Here, we describe the generation of frFAST (far-red Fluorescence Activating and absorption Shifting Tag), a 14-kDa monomeric protein that forms a bright far-red fluorescent assembly with (4-hydroxy-3-methoxy-phenyl)allylidene rhodanine (HPAR-3OM). As HPAR-3OM is essentially non-fluorescent in solution and in cells, frFAST can be imaged with high contrast in presence of free HPAR-3OM, which allowed the rapid and efficient imaging of frFAST fusions in live cells, zebrafish embryo/larvae, and chicken embryos. Beyond enabling the genetic encoding of far-red fluorescence, frFAST allowed the design of a far-red chemogenetic reporter of protein–protein interactions, demonstrating its great potential for the design of innovative far-red emitting biosensors.  相似文献   
7.
地表覆盖内业解译是地理国情普查的一道重要工序。地理国情地表覆盖内业解译现存图斑平面位置精度不足、分类错误多种多样等普遍问题,问题突出典型。文中针对这些问题图文并茂、清晰明了的进行了说明,并从多方面分析问题产生的原因,提出加强对技术指标和采集原则的学习和理解,加强内业与外业的结合,充分发挥解译样本的作用等建议,以有效提高内业解译的质量。  相似文献   
8.
The serine protease, DegP exhibits proteolytic and chaperone activities, essential for cellular protein quality control and normal cell development in eukaryotes. The P. falciparum DegP is essential for the parasite survival and required to combat the oscillating thermal stress conditions during the infection, protein quality checks and protein homeostasis in the extra-cytoplasmic compartments, thereby establishing it as a potential target for drug development against malaria. Previous studies have shown that diisopropyl fluorophosphate (DFP) and the peptide SPMFKGV inhibit E. coli DegP protease activity. To identify novel potential inhibitors specific to PfDegP allosteric and the catalytic binding sites, we performed a high throughput in silico screening using Malaria Box, Pathogen Box, Maybridge library, ChEMBL library and the library of FDA approved compounds. The screening helped identify five best binders that showed high affinity to PfDegP allosteric (T0873, T2823, T2801, RJC02337, CD00811) and the catalytic binding site (T0078L, T1524, T2328, BTB11534 and 552691). Further, molecular dynamics simulation analysis revealed RJC02337, BTB11534 as the best hits forming a stable complex. WaterMap and electrostatic complementarity were used to evaluate the novel bio-isosteric chemotypes of RJC02337, that led to the identification of 231 chemotypes that exhibited better binding affinity. Further analysis of the top 5 chemotypes, based on better binding affinity, revealed that the addition of electron donors like nitrogen and sulphur to the side chains of butanoate group are more favoured than the backbone of butanoate group. In a nutshell, the present study helps identify novel, potent and Plasmodium specific inhibitors, using high throughput in silico screening and bio-isosteric replacement, which may be experimentally validated.  相似文献   
9.
在高校图书馆传统功能定位下,音乐元素的融入受到了极大的限制。音乐及阅读心理治疗等新功能的设置,则将音乐元素更广、更深地融入到高校图书馆的工作中,可更好地为高校广大师生的学习生活提供服务。从高校图书馆传统功能定位下音乐元素的融入和高校图书馆新功能定位下音乐元素的融入两个方面,提出了高校图书馆不同功能定位下对音乐元素运用的思考。  相似文献   
10.
唐代试律诗诗题对有关祥瑞及灵异之类典故的大量选用,不但体现了唐代统治者借祥瑞文化维护自身统治的治国策略,也表明了尚奇之风在唐代的盛行。  相似文献   
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