Hidden roles of the train driver: A challenge for metro automation

In the year 2014, the Helsinki Metro is planned to be fully automated. This automation means that the metro trains will be computer-driven and monitored remotely from a stationary control room. To investigate the challenges related to this scenario, we decided to study the ways in which the current train drivers contribute to the metro system. We conducted three separate but interrelated studies, which were based on the Core-Task Analysis method. Our results suggest that there is much more to driving the metro train than meets the eye. The drivers do not only operate the train on track and its doors at stations, but they also contribute to a variety of other important, albeit more hidden, functions in the metro system. For example, the drivers anticipate, observe, interpret, and react to events in the surrounding environment. Furthermore, they are a significant interaction link between different actors of the metro system. Our conclusion is that if the identified critical roles of the drivers are not accounted for, a migration to a fully automated metro system can affect the quality of service and raise safety issues. In addition to automated metros, the results of this research can be applicable to automation implementations also in other domains.     

Development of a microfluidic design for an automatic lab-on-chip operation

Simple and easy to use are the keys for developing lab-on-chip technology. Here, a new microfluidic circuit has been designed for an automatic lab-on-chip operation (ALOCO) device. This chip used capillary forces for controlled and precise manipulation of liquids, which were loaded in sequence from different flowing directions towards the analysis area. Using the ALOCO design, a non-expert user is able to operate the chip by pipetting liquids into suitable inlet reservoirs. To test this design, microfluidic devices were fabricated using the programmable proximity aperture lithography technique. The operation of the ALOCO chip was characterized from the flow of red-, blue- and un-dyed deionized water. Experimental result indicated that red water, which filled first the analysis area, was substituted entirely with blue water. Controlled sequential flows of these water in the ALOCO device are demonstrated in this paper.     

Crosslinked PVA nanofibers reinforced with cellulose nanocrystals: Water interactions and thermomechanical properties

Acid‐catalyzed vapor phase esterification with maleic anhydride was used to improve the integrity and thermo‐mechanical properties of fiber webs based on poly(vinyl alcohol), PVA. The fibers were produced by electrospinning PVA from aqueous dispersions containing cellulose nanocrystals (CNCs). The effect of esterification and CNC loading on the structure and solvent resistance of the electrospun fibers was investigated. Chemical characterization of the fibers (FTIR, NMR) indicated the formation of ester bonds between hydroxyl groups belonging to neighboring molecules. Thermomechanical properties after chemical modification were analyzed using thermal gravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. An 80% improvement in the ultimate strength was achieved for CNC‐loaded, crosslinked PVA fiber webs measured at 90% air relative humidity. Besides the ultra‐high surface area, the composite PVA fiber webs were water resistant and presented excellent mechanical properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40334.     

Influence of SrO substitution for CaO on the properties of bioactive glass S53P4

Commercial melt-quenched bioactive glasses consist of the oxides of silicon, phosphorus, calcium and sodium. Doping of the glasses with oxides of some other elements is known to affect their capability to support hydroxyapatite formation and thus bone tissue healing but also to modify their high temperature processing parameters. In the present study, the influence of gradual substitution of SrO for CaO on the properties of the bioactive glass S53P4 was studied. Thermal analysis and hot stage microscopy were utilized to measure the thermal properties of the glasses. The in vitro bioactivity and solubility was measured by immersing the glasses in simulated body fluid for 6 h to 1 week. The formation of silica rich and hydroxyapatite layers was assessed from FTIR spectra analysis and SEM images of the glass surface. Increasing substitution of SrO for CaO decreased all characteristic temperatures and led to a slightly stronger glass network. The initial glass dissolution rate increased with SrO content. Hydroxyapatite layer was formed on all glasses but on the SrO containing glasses the layer was thinner and contained also strontium. The results suggest that substituting SrO for CaO in S53P4 glass retards the bioactivity. However, substitution greater than 10 mol% allow for precipitation of a strontium substituted hydroxyapatite layer.     

A comparison of the effect of medium- vs. long-chain triglycerides on the <Emphasis Type="Italic">in vitro</Emphasis> solubilization of cholesterol and/or phytosterol into mixed micelles

Despite clinical evidence of the cholesterol-lowering effects of phytosterols, the exact mechanisms involved are still unclear. Displacement of cholesterol by phytosterols from mixed micelles, which is due to their greater hydrophobicity, is one of the hypotheses for the lumenal effects contributing to the reduction of intestinal cholesterol absorption. In this study a dynamic in vitro lipolysis method was used to examine the solubilization behavior of cholesterol and/or phytosterols during lipolysis to probe the efficacy of cholesterol displacement from mixed micelles by phytosterols. The effects of lipid chain length on sterol solubilization were studied by using microcrystalline suspensions containing 17% phytosterol or cholesterol, formulated in long-chain TG (LCT) and medium-chain TG (MCT). When digesting cholesterol suspended in LCT, the entire cholesterol dose was incorporated into the micellar phase. For the cholesterol formulation suspended in MCT, 50.3% of the initial dose was recovered in the micelles. Under the respective conditions, we observed lower solubilization of phytosterols than of cholesterol (roughly fourfold). Only 25% of the initial phytosterol dose was solubilized from suspensions formulated with LCT, and 13% was solubilized from MCT formulations. Co-administration of phytosterol and cholesterol suspensions showed a significant reduction of cholesterol solubilization, particularly when dosed in MCT, with ≈25% of the cholesterol dose solubilized. Insignificant amounts of cholesterol were displaced by phytosterols when cholesterol was presolubilized in the mixed micelles. The results show that, compared with LCT, mixed micelles containing MCT lipolysis products have a reduced solubilizing capacity for cholesterol, which adds to the effectiveness of the phytosterols in displacing cholesterol. This suggests potential benefits of using medium chain length lipids in cholesterol-lowering phytosterol products.     

Structural Modifications on Chalcone Framework for Developing New Class of Cholinesterase Inhibitors

Due to the multifaceted pharmacological activities of chalcones, these scaffolds have been considered one of the most privileged frameworks in the drug discovery process. Structurally, chalcones are α, β-unsaturated carbonyl functionalities with two aryl or heteroaryl units. Amongst the numerous pharmacological activities explored for chalcone derivatives, the development of novel chalcone analogs for the treatment of Alzheimer’s disease (AD) is among the research topics of most interest. Chalcones possess numerous advantages, such as smaller molecular size, opportunities for further structural modification thereby altering the physicochemical properties, cost-effectiveness, and convenient synthetic methodology. The present review highlights the recent evidence of chalcones as a privileged structure in AD drug development processes. Different classes of chalcone-derived analogs are summarized for the easy understanding of the previously reported analogs as well as the importance of certain functionalities in exhibiting cholinesterase inhibition. In this way, this review will shed light on the medicinal chemistry fraternity for the design and development of novel promising chalcone candidates for the treatment of AD.     

In sweet harmony or in bitter discord? How cultural values and stakeholder requirements shape and users read an urban computing technology

AI & SOCIETY - Culture is, in many ways, implicated in and shapes technology design and use. Inspired by Stuart Hall’s conception of encoding/decoding, we maintain that technological...     

Synthesis and characterization of conducting poly (1-aminonaphthalene), poly (2-aminonaphthalene) and poly (aniline-co-1-aminonaphthalene)

Poly (1&2)-aminonaphthalene and poly (aniline-co-1-aminonaphthalene) have been synthesized in high yields by chemical oxidative polymerization method. The polymers are soluble in polar solvents such as DMSO, NMP etc. In PNA-2 as head-to-tail coupling cannot occur, the electrical conductivity is lower than PNA-1. The copolymer exhibits distinct morphology, higher viscosity, characteristic exciton peak, appreciable thermal stability and electrical conductivity compared to PNA-1.     

Sensitive determination of nitrite in food samples using voltammetric techniques

A [5,10,15,20-tetrakis (4-methoxyphenyl) porphyrinato] manganese (III)chloride (TMOPPMn(III)Cl)-modified gold electrode sensor was developed for the determination of nitrite in food samples. The developed sensor showed an excellent catalytic activity and stability for nitrite oxidation. Under optimized conditions, nitrite concentration as low as 2.9 × 10⁻⁹ M can be determined in various food samples using the developed sensor. Effect of common interfering ions have been investigated in simulated mixtures containing high levels of interfering ions and the sensor was found to be tolerant against these ions. The determination of nitrite in food samples such as chicken ham, sausage and pickled vegetables with the proposed sensor was in good agreement with those obtained by standard spectrophotometric method.     

Effect of soaking time on phase composition and topography and surface microstructure in vitrocrystalline whiteware glazes

The effect of soaking period on the phase composition and topography of raw glazes was discussed. The work had two goals: (i) to establish the potential of manufacturing glazes with a desired surface structure from un-fritted formulations in a fast single cycle for tiles and (ii) to clarify the effects of shortening the firing time on the phase composition and surface roughness of traditionally fired products such as sanitaryware. The results can be applied to adjust the glaze composition for given firing cycles in order to improve the chemical resistance and to achieve the desired microstructure through controlled surface composition.