Encapsulation increases the in vitro bioaccessibility of probiotics in yoghurt

This study examined the encapsulation efficacy of probiotics in yoghurts, product physicochemical properties, the best timing to add encapsulated probiotics during yoghurt manufacturing (before or after fermentation) and their in vitro bioaccessibility. Three different yoghurt types were produced including plain and with encapsulated probiotics added before and after fermentation. A significant (P < 0.05) reduction in total probiotic count was observed in yoghurts containing encapsulated probiotics after 21 days of refrigerated storage. However, the total probiotic count increased during the in vitro colonic fermentation when yoghurts containing encapsulated probiotics were used, indicating increased bioaccessibility of probiotics in the colon.     

Porcine artery elastin preparation reduces serum cholesterol level in rats

The effect of porcine artery elastin on serum cholesterol level was investigated in rats fed a cholesterol-free diet. Rats were fed for 4 weeks, with a diet (ED) containing 15% casein and 5% of porcine artery elastin in comparison with a diet (CD) containing 20% casein. The total serum and non-HDL-cholesterol concentrations were lower (P < 0.001) in ED-fed group than the CD-fed group at the end of the experiment. Caecal propionate concentration and Bifidobacterium and Lactobacillus population were higher (P < 0.05) in ED-fed group than the CD-fed group. The results of this study suggest that porcine artery elastin could be considered as a functional dietary protein with hypocholesterolaemic ability. Favourable amino acid composition and lysine derived cross links may at least be partially responsible for the hypocholesterolaemic ability of ED. Moreover, the higher caecal propionic acid concentration in the ED-fed group may have suppressed the cholesterol synthesis in the liver, and reduced the serum cholesterol level.     

Multimedia and semantic technologies for future computing environments

Research progresses in multimedia computing and systems using semantic technologies have been recently and widely explored. This special issue on multimedia and semantic technologies for future computing environments provides high quality contributions addressing related theoretical and practical aspects of semantic multimedia. We have selected fourteen research papers whose topics are strongly related to the multimedia and semantic technology.     

Bio-electrospraying and aerodynamically assisted bio-jetting the model eukaryotic Dictyostelium discoideum: assessing stress and developmental competency post treatment

Bio-electrospraying (BES) and aerodynamically assisted bio-jetting (AABJ) have recently been established as important novel biospray technologies for directly manipulating living cells. To elucidate their potential in medical and clinical sciences, these bio-aerosol techniques have been subjected to increasingly rigorous investigations. In parallel to these studies, we wish to introduce these unique biotechnologies for use in the basic biological sciences, for handling a wide range of cell types and systems, thus increasing the range and the scope of these techniques for modern research. Here, the authors present the analysis of the new use of these biospray techniques for the direct handling of the simple eukaryotic biomedical model organism Dictyostelium discoideum. These cells are widely used as a model for immune cell chemotaxis and as a simple model for development. We demonstrate that AABJ of these cells did not cause cell stress, as defined by the stress-gene induction, nor affect cell development. Furthermore, although BES induced the increased expression of one stress-related gene (gapA), this was not a generalized stress response nor did it affect cell development. These data suggest that these biospray techniques can be used to directly manipulate single cells of this biomedical model without inducing a generalized stress response or perturbing later development.     

Heavy metal (Zn and Cu) complexation and molecular size distribution in wastewater treatment plant effluent

The size distributions of zinc and copper species in the effluent of a wastewater treatment plant were determined by a combination of ultrafiltration and chelating disk cartridge fractionation. The results showed that 75-87% of total Zn and 84-86% of total Cu were strongly complexed or particle-bound in the final effluents. It was also found that the major part of Cu was bound to ligands in the < 500 Da fraction while the trend for Zn was not so clear and exhibited significant seasonal variability. Labile Cu and Zn were detected not only in the smallest fraction (< 500 Da) but also in the larger fractions. It meant that the labile species in the effluent were not equivalent to free metal ions. Conditional stability constants and ligand concentrations were also determined from the measured metal concentrations by square wave anodic stripping voltammetry. Existence of two types of ligand for each metal was inferred from the experimental data. Conditional stability constant obtained for the stronger type Ligand of Zn was higher than that of Cu, although the estimated Ligand concentrations were almost similar.     

Electrohydrodynamic Atomization of a Concentrated Nano-Suspension

A suspension containing 20-nm-size inorganic particles was subjected to electrohydrodynamic atomization (EHDA) in the stable cone-jet mode. The droplet sizes generated were measured using laser diffraction. These results are compared to the stable cone-jet mode of atomization of a suspension containing 500-nm particles in the same liquid medium. Significant differences in the droplet size distributions were observed. The nano-suspension showed a tri-modal distribution while the micro-suspension was near-monodisperse.     

Silver nanocolloids disrupt medaka embryogenesis through vital gene expressions

Silver nanomaterials are the major components of healthcare products largely because of their antimicrobial effects. However, their unintended toxicity to biological organisms and its mechanism are not well understood. Using medaka fish embryo model, the toxic effects and corresponding mechanisms of silver nanocolloids (SNC, particle size 3.8 ± 1.0-diameter nm) were investigated. SNC caused morphological changes in embryos including cardiovascular malformations, ischemia, underdeveloped central nervous system and eyes, and kyphosis at exposures of 0.5 mg/L. Interestingly, SNC were observed inside the eggs at a level of 786.1 ± 32.5 pg/mg egg weight, and TEM analysis showed that SNC adhered to the surface and inside of the chorion. Meanwhile, medaka oligo DNA microarray and qRT-PCR were used for gene expression analysis in the embryos exposed to 0.05 mg/L SNC for 48 h. As a result, expressions of six of the oxidative stress-, embryogenesis- and morphogenesis-related genes, ctsL, tpm1, rbp, mt, atp2a1, and hox6b6, were affected by the SNC exposure, and these genes' involvement in those malformations was implied. Thus, SNC could potentially cause malformations in the cardiovascular and central nervous systems in developing medaka embryo through SNC-induced differential expression of the genes related to oxidative stress, embryonic cellular proliferation, and morphological development.     

Thermal comfort temperature range for factory workers in warm humid tropical climates

The ability to operate factory buildings as free running will be very useful in the context of saving energy needed for providing adequate thermal comfort for workers in warm humid tropical climatic conditions. The upper limits of thermally comfortable temperatures were established with comfort surveys carried out in three factory buildings without much ventilation. The surveys were then repeated to determine the effects of ventilation as well. The comfort surveys indicated that workers acclimatized to warm humid climatic condition could tolerate up to 30 °C without much ventilation when engaged in light factory work. This comfort temperature limit can be increased up to 34 °C when indoor air velocities are maintained as high as 0.6 m s⁻¹. It is also shown that these studies validate the earlier predictions of adaptive models for warm humid climates. The ability of workers to tolerate elevated temperatures could be used to highlight some concepts that can be considered in the planning of large-scale industrial parks, so that factories could be operated with minimum energy allocated for providing thermal comfort.     

Ethics of resource allocation in developing countries: the case of Sri Lanka

The issues of prioritization of health care services and allocation of resources have recently received increasing attention and discussion. Several reports have been published by governments in different countries and the issues are discussed in many recent books and papers. In this paper the focus is on the problems faced by a developing country when allocation of health care resources is considered. We consider these issues under three headings and exemplify the situation in a developing country by taking Sri Lanka as an example. Firstly the evidence to formulate an ethical basis for the existing health care system in Sri Lanka is discussed, in particular the problem of defining a minimum quality of health care for the population. Secondly, we consider the issues which arise when we want to formulate the ethical basis for health sector reform. In particular, we examine current World Bank proposals. We shall argue that there are a number of important conceptual and ethical issues that have not been properly addressed in the various policy documents. Finally, we introduce our own alternative ethical framework for policy reform.