Dynamic selection of a video content adaptation strategy from a Pareto front

This article is available open access through the publisher’s website through the link below. Copyright @ 2008 The Authors.Genetic Algorithms may be used together with Pareto Optimality in the process of selection of a suitable video content adaptation strategy, the former to return best or fittest solutions that have evolved over many generations and the latter to evaluate and rank each generation's solutions against a set of objectives without the need to assign weights to each one. The outcome of this is a Pareto front of optimal strategies, all of which would satisfy the objectives. The distribution of optimal strategies on a Pareto front, however, suggests that there may be a ‘best-fit’ optimal strategy. This article refines the process of selection of an optimal strategy by taking into account this distribution alongside user preferences, video content characteristics and usage history. In order to make the refined process dynamic, it pursues its implementation using Self-Organising Neural Networks

The right to health equity and how this could be applied to improve women’s access to health care services

According to the Constitution of World Health Organization (1946) “the enjoyment of the highest attainable standard of health is one of the fundamental rights of every human being without distinction of race, religion, political belief, economic or social condition“. To advance health equity there is a need to influence states by material inducement, persuasion and socialization. Health inequities have been slowly recognized by some national courts and human rights tribunals, as violations of human rights. The paper will examine the right of non-discrimination to health care of socially disadvantaged persons, such as women, with an emphasis on the decision by the Committee on the Elimination of Discrimination Against Women (CEDAW) in the Alyne v. Brazil (2003). Particularly, how Alyne’s preventable death came to be seen as a legal wrong and stresses the continuing challenges of ensuring that all these types of wrongs are justiciable in national and constitutional courts. Also, it will be examined, how these courts have applied civil and political rights and economic, social and cultural rights to promote health. The paper will explore the importance of health equity in achieving the Sustainable Development Goals (2030), especially Goal 3 on health and Goal 5 on women’s and girls’ equality. It is essential to analyze how the rights of equality and non-discrimination could be further applied, in order to improve women’s access to health care services and to promote their health. The core elements are to understand heath inequity, the clinical issues and how bioethical principles could be applied to remedy disparities in the context of health care

Novel preparation of controlled porosity particle/fibre loaded scaffolds using a hybrid micro-fluidic and electrohydrodynamic technique.

The purpose of this research was to produce multi-dimensional scaffolds containing biocompatible particles and fibres. To achieve this, two techniques were combined and used: T-Junction microfluidics and electrohydrodynamic (EHD) processing. The former was used to form layers of monodispersed bovine serum albumin (BSA) bubbles, which upon drying formed porous scaffolds. By altering the T-Junction processing parameters, bubbles with different diameters were produced and hence the scaffold porosity could be controlled. EHD processing was used to spray or spin poly(lactic-co-glycolic) (PLGA), polymethysilsesquioxane (PMSQ) and collagen particles/fibres onto the scaffolds during their production and after drying. As a result, multifunctional BSA scaffolds with controlled porosity containing PLGA, PMSQ and collagen particles/fibres were obtained. Product morphology was studied by optical and scanning electron microscopy. These products have potential applications in many advanced biomedical, pharmaceutical and cosmetic fields e.g. bone regeneration, drug delivery, cosmetic cream lathers, facial scrubbing creams etc

The effect of needle tip displacement in co-axial electrohydrodynamic processing

Co-axial electrospraying and electrospinning are versatile electrohydrodynamic (EHD) techniques that can be used to encapsulate a variety of materials in the form of polymeric particles and fibres via a one step process. The successful production of uniform encapsulated products in co-axial EHD (CEHD) processing depends on multiple parameters including solution concentration, applied voltage and needle capillary diameter. Although many studies have been conducted to investigate the effects of these parameters, there has been very limited research on how the axial displacement between the two needle tips affects the final products formed. Hence the purpose of this study was to adjust the positioning of the inner needle such that its tip extends beyond, is level with or resides inside that of the outer needle and to thus determine the most effective arrangement for controlling product size, uniformity and/or yield. Core–shell particles were prepared using two polymers, poly(lactic-co-glycolic)acid (PLGA) as the shell and polymethylsilsesquioxane (PMSQ) as the core and core–shell fibres using PMSQ as the shell and a volatile liquid, perfluorohexane (PFH) as the core. The products formed were analyzed by optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). After analysis, it was concluded that the most effective arrangement for generating both particles and fibres with the optimal combination of size, uniformity and yield was to have the inner needle 2 mm inside the outer needle. This allows for formation of a stable cone–jet and successful encapsulation of the inner liquid within the outer liquid, before the outer stable cone–jet forms. The corresponding collected product diameter and percentage of products in which material was successfully encapsulated were found to be 0.6 ± 0.1 μm and 85 ± 3% respectively for particles and 9 ± 1 μm and 92 ± 2% for fibres

Biomaterials for hollow organ tissue engineering

Tissue engineering is a rapidly advancing field that is likely to transform how medicine is practised in the near future. For hollow organs such as those found in the cardiovascular and respiratory systems or gastrointestinal tract, tissue engineering can provide replacement of the entire organ or provide restoration of function to specific regions. Larger tissue-engineered constructs often require biomaterial-based scaffold structures to provide support and structure for new tissue growth. Consideration must be given to the choice of material and manufacturing process to ensure the de novo tissue closely matches the mechanical and physiological properties of the native tissue. This review will discuss some of the approaches taken to date for fabricating hollow organ scaffolds and the selection of appropriate biomaterials

An online experiment on the influence of online user comments on attitudes toward a minority group

In recent years, there is interest in examining the effects of user comments on online content consumers’ attitudes and perceptions. Building on theoretical foundations from social psychology and using an online experimental design, we investigated whether exposure to online comments attached to news content affects attitudes toward refugees. We recruited students from a public university in the Mediterranean region and, after administering a printed pretest on their attitudes toward refugees, we assigned them into three groups: one that read a series of positive comments about refugees (positive experimental group), one that read a series of negative comments about refugees (negative experimental group) and one that did not read comments (control group). The comments and a neutral reference news video were communicated to the participants via email during a five-day period after the pretest. After the implementation of the experimental stimuli, we administered a modified version of the pretest as a posttest. We found that exposure to positive comments reduced prejudice and that the intensity of prior prejudice was positively associated with the magnitude of prejudice reduction. Exposure to negative comments did not affect prejudice. A repeat posttest, administered one week after the posttest, showed stability of the observed attitude change

Sustained antimicrobial activity and reduced toxicity of oxidative biocides through biodegradable microparticles

The spread of antibiotic-resistant pathogens requires new treatments. Small molecule precursor compounds that produce oxidative biocides with well-established antimicrobial properties could provide a range of new therapeutic products to combat resistant infections. The aim of this study was to investigate a novel biomaterials-based approach for the manufacture, targeted delivery and controlled release of a peroxygen donor (sodium percarbonate) combined with an acetyl donor (tetraacetylethylenediamine) to deliver local antimicrobial activity via a dynamic equilibrium mixture of hydrogen peroxide and peracetic acid. Entrapment of the pre-cursor compounds into hierarchically structured degradable microparticles was achieved using an innovative dry manufacturing process involving thermally induced phase separation (TIPS) that circumvented compound decomposition associated with conventional microparticle manufacture. The microparticles provided controlled release of hydrogen peroxide and peracetic acid that led to rapid and sustained killing of multiple drug-resistant organisms (methicillin-resistant Staphylococcus aureus and carbapenem-resistant Escherichia coli) without associated cytotoxicity in vitro nor intracutaneous reactivity in vivo. The results from this study demonstrate for the first time that microparticles loaded with acetyl and peroxygen donors retain their antimicrobial activity whilst eliciting no host toxicity. In doing so, it overcomes the detrimental effects that have prevented oxidative biocides from being used as alternatives to conventional antibiotics

Nanosecond-pulsed DBD plasma treatment on human leukaemia Jurkat cells and monoblastic U937 cells in vitro

Plasma therapy offers an exciting and novel way of cancer treatment. Specifically, it is shown that Jurkat death rates are closely governed by the plasma treatment time. However, apart from time, alterations to different parameters of treatment process may yield better results. Here, Dielectric barrier discharge (DBD) reactors excited by a nanosecond-pulse energy source are used to investigate cell viability for longer exposure times as well as the effects of polarity of reactor on treatment. Plasma discharge regimes are discussed and assessed using imaging and thermal imaging methods. We found that by changing the polarity of reactor i.e. changing the direction of plasma discharge, the plasma discharge regime changes influencing directly the effectiveness of treatment. Our results showed that ns-DBD− reactor could induce both apoptosis and necrosis of human Jurkat and U937 cells, and this cytotoxic effect of plasma was not completely antagonized by N-acetyl cysteine. It indicates that plasma could induce ROS-independent cell death. Gene expression analyses revealed that p53, BAD, BID and caspase 9 may play vital roles in plasma caused cell death. In addition, our findings demonstrate how different parameters can influence the effectiveness of our reactors. Our assay reveals the custom ability nature of plasma reactors for hematologic cancer therapy and our findings can be used for further development of such reactors using multi-objective optimisation techniques

Poly(3-hydroxyoctanoate), a promising new material for cardiac tissue engineering

Cardiac tissue engineering (CTE) is currently a prime focus of research due to an enormous clinical need. In this work, a novel functional material, Poly(3-hydroxyoctanoate), P(3HO), a medium chain length polyhydroxyalkanoate (PHA), produced using bacterial fermentation, was studied as a new potential material for CTE. Engineered constructs with improved mechanical properties, crucial for supporting the organ during new tissue regeneration, and enhanced surface topography, to allow efficient cell adhesion and proliferation, were fabricated. Our results showed that the mechanical properties of the final patches were close to that of cardiac muscle. Biocompatibility of the P(3HO) neat patches, assessed using Neonatal ventricular rat myocytes (NVRM), showed that the polymer was as good as collagen in terms of cell viability, proliferation and adhesion. Enhanced cell adhesion and proliferation properties were observed when porous and fibrous structures were incorporated to the patches. Also, no deleterious effect was observed on the adults cardiomyocytes' contraction when cardiomyocytes were seeded on the P(3HO) patches. Hence, P(3HO) based multifunctional cardiac patches are promising constructs for efficient CTE. This work will provide a positive impact on the development of P(3HO) and other PHAs as a novel new family of biodegradable functional materials with huge potential in a range of different biomedical applications, particularly CTE, leading to further interest and exploitation of these materials