Tandem reaction of propargylic alcohol, sulfonamide, and N-iodosuccinimide: synthesis of N-(2-iodoinden-1-yl)arenesulfonamide

An efficient and straightforward strategy for the synthesis of N-(2-haloinden-1-yl)arenesulfonamides from propargylic alcohols and sulfonamides is described. Allenesulfonamide is postulated to be the key intermediate for this tandem transformation.     

Construction of a hyperbranched supramolecular polymer as a bifunctional antioxidative enzyme model

A HBSP has been designed as a novel bifunctional enzyme model with SOD and GPx activity by host/guest‐directed self‐assembly of MnTPyP‐M‐Ad and 6‐Te‐diCD. The structure of the host/guest complex was elucidated by ¹H NMR spectra, and the HBSP was characterized by SEM, DLS and measurement of catalytic properties. In the bifunctional enzyme model, the Mn(III) porphyrins act as efficient SOD active sites and the tellurol moieties endow GPx activity. The SOD‐like activity (IC₅₀) of this new supramolecular catalyst was found to be 1.05 × 10^?7 M, which corresponds to 2.82% of the activity of the native SOD enzyme. Besides this, the hyperbranched supramolecular polymer also shows a higher GPx activity (ν₀ = 21.7 × 10^?6 M · min^?1) than other supramolecular enzyme models.

     

Layer-by-layer assembled multilayer films of methoxypoly(ethylene glycol)-block-poly(α,l-glutamic acid) and chitosan with reduced cell adhesion

A methoxypoly(ethylene glycol)-block-poly(α,L-glutamic acid) (mPEGGA) diblock copolymer is synthesized. Using QCM measurements, it is shown that (CS/mPEGGA)(n) film construction takes place over two build-up stages (exponential-to-linear). UV-vis spectra reveal the regular increase of the multilayer film growth at different molecular weights of mPEGGA. Contact angle and surface morphology investigation prove that the hydrophilicity of CS/mPEGGA multilayer film-modified substrate becomes better and the surface becomes rough. Significantly reduced cell adhesion is observed on the CS/mPEGGA multilayer film coated surface.     

Highly specific capture and direct MALDI-MS analysis of phosphorylated peptides using novel multifunctional chitosan-GMA-IDA-Fe (III) nanosphere

In this study, we describe a method for highly specific enrichment of phosphopeptides with multifunctional chitosan–glycidyl methacrylate (GMA)–iminodiacetic acid (IDA)–Fe (III) nanospheres for direct analysis by matrix-assisted laser desorption–ionization mass spectrometry (MALDI-MS). This is the first time that chitosan has been used to create nanospheres support material for selective enrichment of phosphopeptides by modification with GMA, derivatization with IDA, and loading with Fe (III) ions. Chitosan-GMA-IDA-Fe (III) nanospheres with a diameter of 20 to 100 nm have multifunctional chemical moieties which confer unique properties, good dispersibility in highly acidic binding buffers, as well as good biocompatibility and chemical stability which improves their specific interaction with phosphopeptides using various types of acid binding buffers. The process of enrichment is very simple, quick, efficient, and specific. Its high specificity and efficiency for purification of phosphopeptides is reflected in the very low and substoichiometric amounts of phosphopeptides which can be detected, in quantities as low as 1:3,000 M ratios. Compared with other state-of the-art technologies such as the use of conventional Fe³⁺-IMAC and TiO₂, these chitosan nanosphere techniques show superior specificity and sensitivity. Moreover, the resultant chitosan-GMA-IDA-Fe³⁺ nanosphere-absorbed phosphopeptides can be either directly analyzed by MALDI-TOF MS analysis or eluted and further analyzed by nano-LC-MS/MS.     

Peakon, loop and solitary travelling wave solutions for the general modified CH-DP equation

Travelling wave solutions for the general modified CH-DP equation u_t − u_xxt + αu²u_x − βu_xu_xx = uu_xxx are developed. By using the dynamical system method, a peakon and a dark soliton are found to coexist for the same wave speed. Exact explicit blow-up solutions are given. By using numerical simulation, a loop solution for a special case is discussed.     

Analytic Hardy spaces on the quantum torus

Analytic Hardy and BMO spaces on the quantum torus are introduced. Some basic properties of these spaces are presented. In particular, the associated H 1-BMO duality theorem is proved. Finally, we discuss some possible extensions of the obtained results.     

关于分数次Marcinkiewicz积分在Hardy空间上的有界性

本文研究了核函数粗糙的分数次Marcinkiewicz积分μΩ,α在Hardy空间上的有界性.利用Hardy空间的原子分解定理,获得了算子μΩ,α的H1,Ln-nα型和(Hp,Lq)型的有界性结果.     

Optimum selection of the dental implant diameter and length in the posterior mandible with poor bone quality – A 3D finite element analysis

This study aimed to evaluate continuous and simultaneous variations of dental implant diameter and length, and to identify their relatively optimal ranges in the posterior mandible under biomechanical consideration. A 3D finite element model of a posterior mandibular segment with dental implant was created. Implant diameter ranged from 3.0 to 5.0 mm, and implant length ranged from 6.0 to 16.0 mm. The results showed that under axial load, the maximum Von Mises stresses in cortical and cancellous bones decreased by 76.53% and 72.93% respectively, with the increasing of implant diameter and length; and under buccolingual load, by 83.97% and 84.93%, respectively. Under both loads, the maximum displacements of implant-abutment complex decreased by 58.09% and 75.53%, respectively. The results indicate that in the posterior mandible, implant diameter plays more significant roles than length in reducing cortical bone stress and enhancing implant stability under both loads. Meanwhile, implant length is more effective than diameter in reducing cancellous bone stress under both loads. Moreover, biomechanically, implant diameter exceeding 4.0 mm and implant length exceeding 12.0 mm is a relatively optimal combination for a screwed implant in the posterior mandible with poor bone quality.     

A hybrid model for selection of an outsourcing provider

Outsourcing is a good strategy for firms that need to reduce operating costs and improve competitiveness and it is important that firms scientifically select appropriate outsourcing providers. Some efforts have been made to find systematic ways to deal with outsourcing problems, but these efforts incorrectly assumed that the criteria used in the decision process are independent, which is not true in the real world. In this study, we propose a new hybrid multiple criteria decision-making (MCDM) model, which addresses the dependent relationships between the various criteria. The relations-structure among the criteria is built with the aid of the decision-making trial and evaluation laboratory (DEMATEL) method. Decision-makers tend to hold diverse opinions about their preferences due to incomplete information and knowledge, or inherent conflict between various departments. We further used the fuzzy preference programming and the analytic network process (ANP) to form a model for the selection of partners for outsourcing providers. The proposed model can help practitioners improve their decision making process, especially when criteria are numerous and inter-related. The method is demonstrated using data from a Taiwanese airline.