Context-aware pervasive service composition and its implementation

Incorporating service composition and pervasive computing into managing users’ complex everyday activities calls for the Pervasive Service Composition paradigm for everyday life. In this paper, we propose the concept of Context-Aware Pervasive Service Composition (CAPSC), which aims at enabling a pervasive system to provide user service compositions that are relevant to the situation at hand. We investigate CAPSC requirements and design a CAPSC architecture by taking into account context-aware peer coordination, context-aware process service adaptation, and context-aware utility service adaptation. We present a proof of concept application prototype as well.     

Verified stability analysis of continuous-time control systems with bounded parameter uncertainties and stochastic disturbances

For nonlinear systems, feedback control strategies have to be parameterized in such a way that they guarantee asymptotic stability in a certain neighborhood of desired operating points or desired trajectories. Due to not exactly known initial conditions, parameter uncertainties, and measurement errors characterizing dynamic system models in real applications, interval techniques are taken into consideration in this paper to verify stability properties of nonlinear uncertain systems with continuous-time dynamics. These techniques aim at a computation of guaranteed regions of attraction for asymptotically stable equilibria. The practical applicability is shown for the analysis of tracking controllers for ship motions in an uncertain environment. In this application, we focus on analyzing the effects of parameter uncertainties on the domains in the state-space that can be proven to belong to the region of attraction of the desired equilibrium.     

Nanotechnology for Topical Drug Delivery to the Anterior Segment of the Eye

Topical drug delivery is one of the most challenging aspects of eye therapy. Eye drops are the most prevalent drug form, especially for widely distributed anterior segment eye diseases (cataracts, glaucoma, dry eye syndrome, inflammatory diseases, etc.), because they are convenient and easy to apply by patients. However, conventional drug formulations are usually characterized by short retention time in the tear film, insufficient contact with epithelium, fast elimination, and difficulties in overcoming ocular tissue barriers. Not more than 5% of the total drug dose administered in eye drops reaches the interior ocular tissues. To overcome the ocular drug delivery barriers and improve drug bioavailability, various conventional and novel drug delivery systems have been developed. Among these, nanosize carriers are the most attractive. The review is focused on the different drug carriers, such as synthetic and natural polymers, as well as inorganic carriers, with special attention to nanoparticles and nanomicelles. Studies in vitro and in vivo have demonstrated that new formulations could help to improve the bioavailability of the drugs, provide sustained drug release, enhance and prolong their therapeutic action. Promising results were obtained with drug-loaded nanoparticles included in in situ gel.     

Liposomal Formulation of a PLA2-Sensitive Phospholipid–Allocolchicinoid Conjugate: Stability and Activity Studies In Vitro

To assess the stability and efficiency of liposomes carrying a phospholipase A2-sensitive phospholipid-allocolchicinoid conjugate (aC-PC) in the bilayer, egg phosphatidylcholine and 1-palmitoyl-2-oleoylphosphatidylglycerol-based formulations were tested in plasma protein binding, tubulin polymerization inhibition, and cytotoxicity assays. Liposomes L-aC-PC10 containing 10 mol. % aC-PC in the bilayer bound less plasma proteins and were more stable in 50% plasma within 4 h incubation, according to calcein release and FRET-based assays. Liposomes with 25 mol. % of the prodrug (L-aC-PC25) were characterized by higher storage stability judged by their hydrodynamic radius evolution yet enhanced deposition of blood plasma opsonins on their surface according to SDS-PAGE and immunoblotting. Notably, inhibition of tubulin polymerization was found to require that the prodrug should be hydrolyzed to the parent allocolchicinoid. The L-aC-PC10 and L-aC-PC25 formulations demonstrated similar tubulin polymerization inhibition and cytotoxic activities. The L-aC-PC10 formulation should be beneficial for applications requiring liposome accumulation at tumor or inflammation sites.     

Synthesis of cyclic carbonates from epoxides: Use of reticular oxygen of Al2O3 or Al2O3-supported CeOx for the selective epoxidation of propene

Reticular oxygen of Al₂O₃ or CeO_x supported on Al₂O₃ was used for the epoxidation of propene without any double bond cleavage. In batch reaction, Al₂O₃ alone was able to convert propene into propene oxide (PO) with 100% selectivity and 2% conversion of propene with a close to 3:1 ratio with respect to the number of Al(III) reduced to elemental Al. When Ce₂O₃/Al₂O₃ or CeO₂/Al₂O₃ was used, Al remained in its +3 oxidation state, while the Ce oxide was the oxidant as demonstrated by XPS analyses. CeO_x/Al₂O₃ was more active (propene conversion yield of 4–5%) but the selectivity was lower (70%) as PO was isomerized into acetone and propionaldehyde.

Interestingly the use of reticular oxygen very much improves the selectivity with respect to the use of pure O₂. In fact, while propene was more efficiently oxidized (10%) with O₂ in presence of Al₂O₃ or CeO_x/Al₂O₃, the selectivity was as low as 40% because C1 and C2 products were formed. However, the use of reticular oxygen represents a selective two-step technique for the use of molecular oxygen as oxidant of propene. The used oxides can be re-oxidized and the whole process can be further improved towards higher yields.

PO is quantitatively converted into propene carbonate by reaction with CO₂ in presence of Nb₂O₅.     

Effects of Oleic Acid and Phospholipids on the Formation of Lecithin Organogel and Microemulsion

The formation of organogels and microemulsions of lecithin in the presence of a biocompatible cosurfactant, oleic acid, was studied. Low content of oleic acid ([oleic acid]/[lecithin] < 0.1) in the lecithin–oleic acid–dodecane–water system leads to an expansion of the region of existence and to a decrease in the viscosity of lecithin organogels. At high contents of oleic acid ([oleic acid]/[lecithin] > 0.6), low‐viscosity microemulsion exists in the system. Phosphatidylethanolamine, lysophosphatidylcholine, and other phospholipids that are present as impurities in the commercial samples of soybean lecithin can act as cosurfactants. For the first time, the formation of lecithin organogels in the systems containing commercial samples of soybean lecithin with phosphatidylcholine concentrations of 69.3 wt% (Lipoid S75) and 52.9 wt% (Lipoid S45) and saturated aliphatic hydrocarbons is demonstrated. The gelation is observed at T =25 °C in octane, decane, dodecane, and hexadecane for Lipoid S75 and in dodecane and hexadecane for Lipoid S45. A decrease in the degree of purification of lecithin leads to an expansion of the regions of existence of the organogels and to a reduction of their viscosity.     

Effect of strain level on stress relaxation and recovery behaviors of isotactic biaxially oriented polypropylene films

The long‐term recovery process and the changes in the uniaxial tensile properties and in the structure of isotactic biaxially oriented polypropylene (i‐boPP) films after pre‐extended at strain levels ranging from 1% up to 130% at room conditions were examined by using tensile testing, Fourier transform infrared spectroscopy/attenuated total reflectance, atomic force microscopy, and X‐ray diffraction methods. It is significantly observed that the pre‐extended i‐boPP films at strain levels from 1% to 6% recovered completely back to their initial lengths and tensile properties. However, the i‐boPP films showed a very slow recovery process and obtained very high remaining deformations changing with time which indicates irreversible structural processes after they were extended at higher strain levels. In order to predict the remaining deformation or length and the characteristics of the recovery process at any time, the linear equation of strain with respect to log time was proposed. The reasons for the changes in the tensile properties, the morphology, and the structure of the pre‐extended i‐boPP films were examined in detail. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42948.     

Neuroprotective Properties of Quinone Reductase 2 Inhibitor M-11, a 2-Mercaptobenzimidazole Derivative

The ability of NQO2 to increase the production of free radicals under enhanced generation of quinone derivatives of catecholamines is considered to be a component of neurodegenerative disease pathogenesis. The present study aimed to investigate the neuroprotective mechanisms of original NQO2 inhibitor M-11 (2-[2-(3-oxomorpholin-4-il)-ethylthio]-5-ethoxybenzimidazole hydrochloride) in a cellular damage model using NQO2 endogenous substrate adrenochrome (125 µM) and co-substrate BNAH (100 µM). The effects of M-11 (10–100 µM) on the reactive oxygen species (ROS) generation, apoptosis and lesion of nuclear DNA were evaluated using flow cytometry and single-cell gel electrophoresis assay (comet assay). Results were compared with S29434, the reference inhibitor of NQO2. It was found that treatment of HT-22 cells with M-11 results in a decline of ROS production triggered by incubation of cells with NQO2 substrate and co-substrate. Pre-incubation of HT-22 cells with compounds M-11 or S29434 results in a decrease of DNA damage and late apoptotic cell percentage reduction. The obtained results provide a rationale for further development of the M-11 compound as a potential neuroprotective agent.     

Modeling and management of profiles and competencies in VBEs

Virtual organization Breeding Environments (VBEs) are long-term clusters/associations of autonomous and geographically dispersed organizations in the market and society. The VBE aims to prepare its member organizations and enhance their readiness for potential involvement in opportunity-based Virtual Organizations (VOs). Organizing/management of profiles is a key activity in VBEs. The need for management of profiles is even larger in medium-size and large-size VBEs (e.g. with more then 50 members), where typically the member organizations do not have the chance of getting to know all others directly. Furthermore, uniform structuring/modeling of the mostly textual content of profiles enables their processing by the software that supports variety of VBE functionality. An important element of the profiles in VBEs is the competency. There is no consensus on the definition of competency and the existing literature associate it with a range of tangible characteristics such as resources and products, as well as intangible characteristics such as knowledge and motivation. This paper introduces and details a unified/generic model for VBE profiles and VBE competencies. It further addresses the design of an adaptable, replicable and sustainable Profile and Competency Management System (PCMS), which is being developed supported by the ontology for profiles and competencies. An approach and mechanism for semi-automated derivation/discovery of elements for organization’s profile and competency from on-line text corpora is also introduced.