电子转移反应理论及其进展

电子转移反应是近年来自然科学中十分活跃的研究领域,是化学研究的前沿课题之一。本文讨论(1)Marcus理论大意:(2)Marcus理论对倒置区域的预测;(3)电子转移理论的进展。     

如何确定我国国际储备的适度规模

国际储备的适度规模问题一直是国际金融学界探讨的焦点。近年来，我国国际储备的数量增长非常迅速，这引起了对我国应持有的合理国际储备规模的激烈讨论。通过阐述我国国际储备的增长过程及原因，指出大量持有国际储备的利弊：持有国际储备既能获得一定的收益，又会产生一定的成本，因此，一国的国际储备并非多多益善。最后，得出确定适度的国际储备规模的方法——成本一收益综合分析法。     

Investigation of the Vibration Behavior of Fluidelastic Instability in Closely Packed Square Tube Arrays

Flow-induced vibrations in heat exchanger tubes have led to numerous accidents and economic losses in the past. Fluidelastic instability is the most critical flow-induced vibration mechanism in heat exchangers. Both experimental and computational studies conducted to determine fluidelastic instability were presented in this paper. In the experiment, a water channel was built, and a closely packed normal square tube array with a pitch-to-diameter ratio of 1.28 was tested, and significant fluidelastic instability was observed. A numerical model adopting large-eddy simulation and moving mesh was established using ANSYS CFX, and results showed good agreement with the experimental findings. The vibration behaviors of fluidelastic instability were discussed, and results showed that the dominant vibration direction of the tubes changed from streamwise to transverse beyond a critical velocity. A 180° phase lag between adjacent tubes was observed in both the experiment and simulations. Normal and rotated square array cases with pitch-to-diameter ratios of 1.28 and 1.5 were also simulated. The results of this study provide better insights into the vibration characteristics of a square tube array and will help improve the fundamental research and safety design of heat exchangers.     

《看虹录》:生命的另一种形式

沈从文的短篇小说《看虹录》是运用费洛伊德心理分析方法进行心理小说创作实验的典范之作。在对小说的研究中,笔者发现,它叙述了一个弗洛伊德式的“白立梦”,通过本我、自我、超我三个层次的“我”的心灵展示,肯定了超越于社会道德法则之上的生命的另一种形式－自然神性。4年代初,在以抗战宣传为主要特征的时代文学氛围中,沈从文坚持现代主义探索,坚守艺术的独立价值,给后人留下了宝贵的艺术经验和精神启迪。     

Hyperbaric oxygen therapy improves the effect of keloid surgery and radiotherapy by reducing the recurrence rate

Objective

Keloids are exuberant cutaneous scars that form due to abnormal growth of fibrous tissue following an injury. The primary aim of this study was to assess the efficacy and mechanism of hyperbaric oxygen therapy (HBOT) to reduce the keloid recurrence rate after surgical excision and radiotherapy.

Methods

(1) A total of 240 patients were randomly divided into two groups. Patients in the HBOT group (O group) received HBOT after surgical excision and radiotherapy. Patients in the other group were treated with only surgical excision and radiotherapy (K group). (2) Scar tissue from recurrent patients was collected after a second operation. Hematoxylin and eosin (H&E) staining was used to observe keloid morphology. Certain inflammatory factors (interleukin-6 (IL-6), hypoxia-inducible factor-1α (HIF-1α), tumor necrosis factor-α (TNF-α), nuclear factor κB (NF-κB), and vascular endothelial growth factor (VEGF)) were measured using immunohistochemical staining.

Results

(1) The recurrence rate of the O group (5.97%) was significantly lower than that of the K group (14.15%), P<0.05. Moreover, patients in the O group reported greater satisfaction than those in the K group (P<0.05). (2) Compared with the recurrent scar tissue of the K group, the expression levels of the inflammatory factors were lower in the recurrent scar tissue of the O group.

Conclusions

Adjunctive HBOT effectively reduces the keloid recurrence rate after surgical excision and radiotherapy by improving the oxygen level of the tissue and alleviating the inflammatory process.

     

激励机制在高校管理中的运用

激励机制是高校多出人才、快出人才的重要手段和措施，高校必须采用相应的激励措施，用激励手段激活人才战略的全局。     

三种防治因子对南方根结线虫胚胎发育及二龄幼虫作用的比较

本文详细研究了粗皮侧耳 (Pleurotusostreatus)发酵液对南方根结线虫 (Meloidogyneincognita)卵及二龄幼虫的作用 ,证明粗皮侧耳发酵液确能产生杀线虫毒素 ,该毒素对卵与二龄幼虫均有明显触杀作用 ,在相同条件下 ,二龄幼虫比卵对毒素更敏感。在粗皮侧耳发酵液 10倍浓缩液作用下 ,对卵的相对防效达 18.4～ 35 .2 % ,室温处理二龄幼虫 2 4h死亡率高达 79.4 1± 1.74 %。     

课程视角:贫困农村地区初中学生辍学原因分析——一所农村初级中学的个案研究

农村初中学生辍学率居高不下,一直是"普九"顺利推进的瓶颈,这在贫困农村地区显得尤为突出.以往的相关研究,大多将原因归结为经济贫困.     

Improvement in the Orthogonal Protein Degradation in Escherichia coli by Truncated mf-ssrA Tag

SsrA peptide tag from Mycoplasma florum has been developed as a versatile biotechnology tool to control orthogonal degradation of tagged proteins in Escherichia coli. Here, using the systematic deletion mutants of mf-ssrA tag, we demonstrated that the residues in two separate regions have different functions in mf-Lon-mediated specific orthogonal target protein degradation in E. coli. The deletion of multiple residues, up to six amino acids, did not fatally abolish its specific degradation activity, instead of being able to improve the stability of the tagged protein in the presence of endogenous proteases before mf-Lon expression in E. coli. Except for previously identified essential residues, the region adjacent to the C-terminal of the mf-ssrA tag was involved in mf-Lon and endogenous protease-mediated degradation. Moreover, the deletion of specific residues made the mf-ssrA tag more effective and compact. The mf-ssrA tag can be implemented in synthetic biology and bioengineering for development of synthetic circuits.     

投资者关系管理研究

在成熟的资本市场上，投资关系管理已经成为一种潮流，在我国却只是刚刚起步。针对这种现实，在对投资关系管理的产生与发展作一简要历史回顾的基础上，分析加强投资关系管理的现实意义，进而剖析我国投资关系管理的发展现状及其落后原因，提出加强我国投资关系管理的若干建议与措施，就显得十分必要。