Development of elastic and plastic properties of polyoxymethylene during bending fatigue

The development of the plastic and viscoelastic properties and the corresponding failure limits of the acetal homopolymer polyoxymethylene were studied in unidirectional cyclic fatigue. Samples with molecular weights (MWs) ranging from 90 to 142 kg/kmol were tested in displacement‐controlled conditions, resulting in maximum stress amplitudes between 30 and 59 MPa and strain amplitudes between 35.8 and 92.6 με. The zero‐hour material properties and the cycle‐dependent property development were predominantly dictated by deformations in the crystalline regions and showed a negligible dependence on MW. However, the final failure limits were found to be primarily dependent on the length of the amorphous tie chains that connect the crystallites. As such, fatigue life analysis showed a strong dependence on MW. Results are interpreted in light of the primary mechanical failure mechanisms and the corresponding molecular deformations. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40762.     

Characterization of Starch from Maize Endosperm Mutants

Some maize endosperm mutants have branched-chain starch components with long exterior chains which make the blue-value procedure for estimating amylose content questionable. Gel filtration was used to estimate starch composition of normal, high-amylose, waxy and other maize endosperm mutants. Loosely-branched polymers appeared responsible for the apparent amylose content. In some mutants high and intermediate loosely branched polysaccharides were found in addition to amylose. The sweet corn background of some endosperm genotypes influenced the types of polymers produced compared to the dent backgrounds used by previous researchers.     

Comparison of two low-hazard organic solvents as individual and cosolvents for the fabrication of polysulfone membranes

Petroleum-derived solvents commonly used in membrane fabrication are often hazardous and toxic, so the investigation of safer alternatives is important. In this study, two low-hazard solvents, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (Rhodiasolv® PolarClean) and gamma-valerolactone (GVL), were investigated as sole solvents and as cosolvents to cast polysulfone membranes via nonsolvent induced phase inversion. Normalized viscosity was introduced as an indicator of dope solution homogeneity and was used to compare the required time of mixing to achieve full dissolution of the polymer in the different solvents/solvent mixtures. All dope solutions made with low-hazard solvents were found to be more viscous than those made with traditional solvents, which meant additional mixing time was needed, and that fabricated membranes were morphologically different. With respect to operation, membranes cast from dope solutions containing equal amounts of PolarClean and GVL displayed the most similar flux curves and solute rejection to those made using the traditional solvent tested.     

Synthesis and Anticancer Properties of Oxazepines Related to Azaisoerianin and IsoCoQuines

In this article, we report the synthesis and biological properties of a series of novel oxazepines related to isoCA-4 having significant antitumor properties. Among them, three oxazepin-9-ol derivatives display a nanomolar or a sub-nanomolar cytotoxicity level against five human cancer cell lines (HCT116, U87, A549, MCF7, and K562). It was demonstrated that the lead compound in this series inhibits tubulin assembly with an IC₅₀ value of 1 μM and totally arrests the cellular cycle in the G2/M phase at the low concentration of 5 nM in HCT116 and K562 cells. Molecular modeling studies perfectly corroborates these promising results.     

适应与抵制：越南为应对气候变化采取的措施

首先,以当前应对气候变化的措施发展的批判性立场为切入点,提出一种对于世界范围的景观越来越适用、近乎通用的“工具箱”假设。它提出了一种逻辑上的反思并开拓了具有在相似内容中反复提炼出来的一系列地理与社会文化原则的设计方案。它否认空间的普遍性意义和逐渐增长的对于效能评估标准的依赖,反而强调文化适用性与地理特殊性的影响力。为证明这些假设,以近年来作者和他人协同越南合作伙伴设计的越南当地项目为重点。最终,针对气候变化制定六大主题。这些主题将细致分析周围景观的场域特定和自然逻辑作为基础,而这一逻辑又与其生态基础以及社会和文化密不可分。提出的一系列策略有助于缩小经济与生态、文化与自然、城市主义与景观之间的分歧,同时适应气候变化带来的新挑战,并抵制同质化的应对措施。     

On the joint effects of stimulus quality, regularity, and lexicality when reading aloud: New challenges.

A number of computational models have been developed over the last 2 decades that are remarkably successful at explaining the process of translating print into sound. Nevertheless, 2 of the most successful computational accounts on the table fail to simulate the results from factorial experiments reported in this article in which university students read aloud letter strings that varied in terms of spelling–sound regularity and lexicality (regular words vs. exception words vs. nonwords) and stimulus quality (bright vs. dim). Skilled readers yielded additive effects of regularity and stimulus quality and additive effects of lexicality and stimulus quality on both RT and errors when nonwords were mixed with words. When only words appeared in the list, there was an interaction in which exception words were less affected by low stimulus quality than regular words were; no existing account anticipates or explains these results. We advance a hypothesis that assumes a novel module that accommodates these data and provide an existence proof in the form of a simulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Situvis: A sensor data analysis and abstraction tool for pervasive computing systems

Pervasive systems are large-scale systems consisting of many sensors capturing numerous types of information. As this data is highly voluminous and dimensional, data analysis tasks can be extremely cumbersome and time-consuming. Enabling computers to recognise real-world situations is an even more difficult problem, involving not only data analysis, but also consistency checking. Here we present Situvis, an interactive visualisation tool for representing sensor data and creating higher-level abstractions from the data. This paper builds on previous work, Clear et al. (2009) [8] through evolved tool functionality and an evaluation of Situvis. A user-trial consisting of 10 participants shows that Situvis can be used to complete the key tasks in the development process of situation specifications in over 50% less time than an improvised alternative toolset.     

Video game training to improve selective visual attention in older adults

The current study investigated the effect of video game training on older adult’s useful field of view performance (the UFOV® test). Fifty-eight older adult participants were randomized to receive practice with the target action game (Medal of Honor), a placebo control arcade game (Tetris), a clinically validated UFOV training program, or into a no contact control group. Examining pretest–posttest change in selective visual attention, the UFOV improved significantly more than the game groups; all three intervention groups improved significantly more than no-contact controls. There was a lack of difference between the two game conditions, differing from findings with younger adults. Discussion considers whether games posing less challenge might still be effective interventions for elders, and whether optimal training dosages should be higher.     

Corrosion under mixed flowing gas conditions of various connector coatings

This paper presents an investigation on the corrosion performance of Ni/Au, NiP/Au, Ni/NiP/Au and Ni/NiPd/Au electrical connector coating systems. The coating systems were exposed to 10 days Class III mixed flowing gas and were subsequently examined by X‐ray diffraction, focused ion beam microscopy, scanning electron microscopy and energy dispersive spectroscopy to evaluate the performance of each coating system. The Ni/Au coating system showed the worst performance followed by NiP/Au and Ni/NiP/Au. The Ni/NiPd/Au coated connector materials exhibited the least surface corrosion and this was attributed to a number of factors including a thicker coating system, more compact gold layer with fewer defects and a reduction in the electrochemical potential difference between layers reducing the local cell effect.