Locally biholomorphic mappings of multiconnected domains

Sufficient conditions were found in [1, 2] for a domain in the complex plane to admit a finitely valent locally biholomorphic mapping of the whole plane. In this article we find the relevant necessary and sufficient conditions. Also, we answer the question that was posed by Aksent’ev and Ul’yanov in connection with the problem under consideration. The answer yields a lower bound for the valency while generalizing a result of [3] to polydisks.     

On Meromorphic Starlike Multivalent Functions

In this paper we introduce and study some new subclasses of meromorphic starlike multivalentfunctions.Inclusion relations are established,Integral transforms of functions in these classes are alsoconsidered.In particular,our results include or improve several results due to Mogra et al.[2],Mogra[3],Goel and Sohe[4]and Bajpai[5].     

Subordination properties for meromorphic multivalent functions associated with the multiplier transformation

The purpose of the present paper is to obtain some sandwich-type theorems, which are combined by subordination and superordination preserving properties associated with a certain family of multiplier transformations for meromorphic multivalent functions in the punctured open unit disk.     

Processes of DNA condensation induced by multivalent cations： Approximate annealing experiments and molecular dynamics simulations

The condensation of DNA induced by spermine is studied by atomic force microscopy （AFM） and molecular dynamics （MD） simulation in this paper. In our experiments, an equivalent amount of multivalent cations is added to the DNA solutions in different numbers of steps, and we find that the process of DNA condensation strongly depends on the speed of adding cations. That is, the slower the spermine cations are added, the slower the DNA aggregates. The MD and steered molecular dynamics （SMD） simulation results agree well with the experimental results, and the simulation data also show that the more steps of adding multivalent cations there are, the more compact the condensed DNA structure will be. This investigation can help us to control DNA condensation and understand the complicated structures of DNA--cation complexes.     

Untapped Opportunities of Resin-to-Resin Transfer Reactions (RRTR) for the Convergent Assembly of Multivalent Peptide Conjugates

Handling of the individual fragments remains a bottleneck in the convergent assembly of peptides. Overlooked since the emergence of ligation chemistries during the past two decades, so-called resin-to-resin transfer reactions (RRTR) are here described as a strategic shortcut in this context. Condensation of the involved moieties at an acceptor resin is facilitated by shuttling peptide segments directly from a donor resin in a one-pot fashion. The straightforward synthesis of a sterically constrained 13-mer peptidosteroid model illustrates the utility of this approach, presenting the first successful application of the RRTR methodology in the field of multivalent design and bioconjugation. Relying on established procedures to generate, monitor and isolate intermediates and products, the solid-phase nature of the entire strategy allows for the fast construction of polypeptide adducts and libraries thereof. As such, a rejuvenated use and new opportunities for RRTR are reported.     

STXM-NEXAFS研究铁(III)离子诱发柠檬酸在高岭石表面的固定机制

热带地区土壤有机碳的稳定性受有机碳与高岭石、三价铁离子[Fe（Ⅲ）]交互作用的强烈影响.低分子量有机酸（LMWOAs）是土壤有机碳中最易被微生物降解的组分,研究LMWOAs在高岭石-Fe（Ⅲ）-LMWOAs三相系统中的固定机制对于理解热带地区土壤有机碳循环具有重要意义;然而LMWOAs在该三相系统中固定机制仍不清楚,并缺乏分子水平上的直接证据.本研究以柠檬酸（CA）为LMWOAs的典型代表,通过采集Fe/CA初始物质的量比2.0条件下获取的吸附样品,利用同步辐射X射线扫描透射显微术（STXM）在亚微米尺度上表征C,Fe和Si的分布特征,发现C-Fe分布的相关性与C-Si分布相当;并在高C,Fe微区中利用C的K边和Fe的L₃边X射线近边吸收精细结构谱（NEXAFS）在分子水平上揭示了Fe在不同富集微区分别以水铁矿和高岭石-Fe（Ⅲ）-CA三元配合体形式存在,从而表明水铁矿诱发的吸附/共沉淀以及以Fe（Ⅲ）为架桥形成高岭石-Fe（Ⅲ）-CA三元配合作用是CA固定的重要机制.本研究成果对于理解热带地区土壤中CA稳定性和低分子量有机酸的碳固定和循环机制提供了重要科学依据.     

Supramolecular Mobility in Polyrotaxanes Exploits Biomedical Functions

The mobility of cyclodextrins (CDs) threaded onto a linear polymeric chain and the dethreading of the CDs from the chain are the most fascinating features seen in polyrotaxanes. These structural characteristics are very promising to their possible applications in biomedical use. Enhancing multivalent interaction between ligand-receptor systems by using ligand-polyrotaxane conjugates is one of the excellent properties related to the CD mobility. Gene delivery using cytocleavable polyrotaxanes is more practical but highly crucial in drug delivery. Such a supramolecular approach using CD-containing polyrotaxanes is extensively expected to exploit a new paradigm of advanced biomaterials for future medicines.     

致病菌与糖的特异性识别及其分析应用研究

致病菌往往通过凝集素-糖特异性识别来实现对宿主细胞的粘附,进而感染宿主组织,引起病变。因此,研究致病菌与糖的特异性识别有利于进一步了解感染性疾病的致病机制,为致病菌的特异性检测和感染性疾病的治疗提供新的策略。该文总结了致病菌-糖特异性识别的相关机制机理;介绍了目前主要的研究方法和技术,特别评述了荧光光谱、表面等离子体共振、电化学阻抗谱及石英晶体微天平等技术在该研究中的应用现状,并对这4种技术与微流控芯片平台的结合进行了探讨;针对致病菌检测特异性差、耐药性严重等难题,重点综述了致病菌-糖的特异性识别在细菌分离、富集、检测、鉴别、生物膜抑制及抗菌糖类药物筛选方面的应用。最后对致病菌-糖特异性识别基础和应用研究进行了展望。     

糖簇分子和糖树状分子及其生物学活性

糖簇分子和糖树状分子是近年来发展起来的一类新型糖缀合物,其目的是模拟天然存在的“多元效应”。本文主要综述了目前已知糖簇分子和糖树状分子所具有的生物活性及其潜在的应用领域。     

Recent Progress in the Synthesis of the Monocarba-closo-dodecaborate(−) Anions

This Concept article focuses on the rapid growth in studies of the chemistry of the monocarba-closo-dodecaborate(−) anion (C1 carborane anion). As one of the most stable anions known, the C1 carborane anion has been useful for exploring the chemistry of highly reactive cations. On the other hand, development of novel functional molecules utilizing the unique properties of C1 carborane anion (e.g., σ-aromaticity, rigid spherical skeleton) has progressed more slowly. The main reason for this is the relatively undeveloped state of synthetic chemistry in this area. Recent advances in the synthetic chemistry of C1 carborane anion are highlighted in this Concept article, focusing on cross-coupling reactions at the carbon vertex, direct conversion of B−H bonds, and the synthesis of multivalent weakly coordinating anions. These progressions move this species beyond its well-established role of highly stable “counter” monocharged anion.