Synthesis and antioxidant properties of fullero-steroidal covalent conjugates

Four new fullero-steroids were synthesized starting from γ-aminobutyric acid (GABA)-incorporated fulleropyrrolidine and corresponding sterols. The synthesis, characterization, preliminary study on in vitro antioxidant activity as well as the steady state photophysical properties are presented. All synthesized compounds showed antioxidant activity 2-3-fold higher than the parent fullerene. The most active compound appeared to be as potent as standard antioxidant BHT (2,6-di-tert-butyl-4-methylphenol). Also, all of them fluoresce 6-8-fold stronger than C₆₀, thus representing potential irradiation assisted pro-oxidants. With significantly increased lipophilicity, it could be expected that attached steroidal subunit enables better penetration of C₆₀ to living cell membranes, thus facilitating its antioxidant activity. Based on all obtained results, newly synthesized covalent fullero-steroidal conjugates represent good candidates for potential antioxidants as well as pro-oxidants.     

Endometriosis of the bladder muscular layer as a cause of acute abdomen

OBJECTIVES: A case of acute abdomen arising from endometriosis of the bladder is described. The rarity of this condition prompted us to report on the present case and the problems encountered in making the differential diagnosis. METHODS/RESULTS: A patient with endometriosis of the muscle layer of the bladder mimicking acute gynecological abdomen is described. CONCLUSIONS: Endometriosis of the bladder is extremely rare and usually presents as urinary problems and rarely as acute abdomen.     

AO4BPEL: An Aspect-oriented Extension to BPEL

Process-oriented composition languages such as BPEL allow Web Services to be composed into more sophisticated services using a workflow process. However, such languages exhibit some limitations with respect to modularity and flexibility. They do not provide means for a well-modularized specification of crosscutting concerns such as logging, persistence, auditing, and security. They also do not support the dynamic adaptation of composition at runtime. In this paper, we advocate an aspect-oriented approach to Web Service composition and present the design and implementation of AO4BPEL, an aspect-oriented extension to BPEL. We illustrate through examples how AO4BPEL makes the composition specification more modular and the composition itself more flexible and adaptable.     

How do development actors do “ICT for development”? A strategy‐as‐practice perspective on emerging practices in Ghanaian agriculture

This paper examines how development actors within the Ghanaian agricultural sector enact information and communication technology (ICT) in their day‐to‐day outreach practices with smallholder farmers. We draw on an in‐depth qualitative case study, informed by the theoretical perspective of “strategy‐as‐practice” to answer the research question: “what ICT‐mediated strategic practices are used by development actors in the Ghanaian agriculture sector?” The research findings reveal that (1) the activities of development actors are meshed within a network of interdependencies; (2) the enacted strategic practices reflect the trade‐off between novelty of content and novelty of the technologies used to deliver it; and lastly, (3) the praxis of development actors for doing ICT for development consists of hybrid strategies, combining bottom‐up approaches consistent with farmers' indigenous smallholder logic, with top‐down imperatives framing agriculture “as a business” and nurturing value‐chain integration. Consequently, our research points to the impact of ICT initiatives as step‐wise and attained over the long term, rather than disruptive and attained in the immediate term.     

Terahertz reflectivities of metal-coated mirrors

Terahertz (THz) reflectivities of a variety of metal-coated mirrors were measured. Gold, silver, and aluminum coatings were tested and compared. It was found that all types of optical metal-coated mirrors perform equally well as THz reflectors.     

An X-ray micro-fluorescence study to investigate the distribution of Al, Si, P and Ca ions in the surrounding soft tissue after implantation of a calcium phosphate-mullite ceramic composite in a rabbit animal model

Synthetic calcium phosphates, despite their bioactivity, are brittle. Calcium phosphate- mullite composites have been suggested as potential dental and bone replacement materials which exhibit increased toughness. Aluminium, present in mullite, has however been linked to bone demineralisation and neurotoxicity: it is therefore important to characterise the materials fully in order to understand their in vivo behaviour. The present work reports the compositional mapping of the interfacial region of a calcium phosphate--20 wt% mullite biocomposite/soft tissue interface, obtained from the samples implanted into the long bones of healthy rabbits according to standard protocols (ISO-10993) for up to 12 weeks. X-ray micro-fluorescence was used to map simultaneously the distribution of Al, P, Si and Ca across the ceramic-soft tissue interface. A well defined and sharp interface region was present between the ceramic and the surrounding soft tissue for each time period examined. The concentration of Al in the surrounding tissue was found to fall by two orders of magnitude, to the background level, within ~35 μm of the implanted ceramic.     

How well are color components of samples of the Natural Color System estimated?

The aim of this study was to determine how accurately color-normal subjects that have received basic information about, but do not have practical experience with, the Natural Color System (NCS) can estimate the Heringian components of a representative selection of samples. Twenty-five color-normal subjects, taking part in two trials with at least a 24 h gap between assessments, selected four samples representing individual unique hues (uHs) from a set of 40 highly chromatic NCS samples on a rotatable tray. The samples selected for assessment of components were displayed to the subjects who estimated the hue components of 16 high-chroma samples, hue and white/black components of 16 tonal color samples, and three achromatic samples with different blackness values. Variability in selection of samples representing uHs as well as the relationship between the subjects' estimates of unique hue components and the defined values of the system was obtained. It was found that hues alone are easier to correctly estimate than hues together with white and black and that the components of colors of higher chroma are easier to estimate accurately than those of lower chroma. It was also found that, for R and G, the mean uH choices of subjects differed very little from the NCS's R and G, whereas selections for yellow and blue deviated, the former by 1.22 hue steps (slightly greener than G90Y), and the latter by 1.36 hue steps (represented approximately by R85B). This may impact the accuracy of color models that employ NCS unique hues.     

Multifactorial analysis of acetaldehyde kinetics during alcoholic fermentation by Saccharomyces cerevisiae

Acetaldehyde is the terminal electron acceptor in the alcoholic fermentation by Saccharomyces cerevisiae. Quantitatively the most important carbonyl by-product, it has relevance for ethanol production yields as well as product stabilization and toxicology. The aim of this study was to investigate the effect of various enological parameters on acetaldehyde kinetics during alcoholic fermentations. Two commercial yeast strains were tested in two grape musts and the pH, temperature, SO₂ and nutrient addition were varied. All incubations had uniform kinetics where acetaldehyde reached an initial peak value followed by partial reutilization. Peak acetaldehyde concentrations and residual concentrations after 15 days of fermentations ranged from 62 to 119 mg l^− 1 and 22 to 49 mg l^− 1, respectively. A positive linear relationship was found between peak and final acetaldehyde levels in Gewürztraminer, but not Sauvignon Blanc fermentations, where sluggish fermentations were observed. Several factors had a significant effect on peak and/or final acetaldehyde levels. SO₂ addition, grape cultivar and fermentation nutrition were important regulators of peak acetaldehyde production, while final acetaldehyde concentrations were correlated with SO₂ addition, grape cultivar and temperature. The results allowed to estimate the acetaldehyde increase caused by SO₂ addition to 366 ??g of acetaldehyde per mg of SO₂ added to the must. The course of the final fermentation phase was shown to determine acetaldehyde residues. Comparison of acetaldehyde and hexose kinetics revealed a possible relationship between the time of occurrence of peak acetaldehyde concentrations and the divergence of glucose and fructose degradation rates.