Inclusive education in Bulgaria and Bosnia and Herzegovina: policy and practice

This paper examines developments in inclusive education in Bulgaria (BG) and Bosnia and Herzegovina (B&H) in the context of actual and desired accession to the European Union respectively. It seeks to provide insights into the national special education traditions in these countries and aims to establish how these have influenced current developments in inclusive education together with and alongside powerful external change agents. This research focuses on policy makers' perspectives on changes associated with inclusion. There are significant similarities in the way inclusive education reforms are being perceived and implemented in both countries, and analysis suggests there is a strong need for regional co-operation with shifts in both policy and practice

PEGylation affects the self-assembling behaviour of amphiphilic octapeptides

Surfactant-like peptides are a class of amphiphilic macromolecules, which are able to self-assemble in water forming different supramolecular structures. Among them, octapeptides composed of six hydrophobic and two hydrophilic residues have attracted interest since they have a length similar to those of natural phospholipids. Supramolecular structures of different amphiphilic octapeptides have been widely reported, but no study has been performed aimed at investigating the effect of PEGylation on their self-assembling behaviour. The aim of the present work was to synthesize and characterise the self-assembling behaviour of PEGylated alanine- or valine based amphiphilic octapeptides (mPEG1.9kDa-DDAAAAAA and mPEG1.9kDa-DDVVVVVV) in comparison to the non-PEGylated ones (DDAAAAAA and DDVVVVVV). The self-aggregation process in ultrapure water was investigated by fluorescence spectroscopy, small angle neutron scattering (SANS), dynamic light scattering (DLS), while the secondary structure was assessed by circular dichroism. PEGylation markedly affects the self-assembling behaviour of these amphiphilic octapeptides in terms of both critical aggregation concentration (CAC) and shape of the formed supramolecular aggregates. Indeed, PEGylation increases CAC and prevents the self-aggregation into fibrillary supramolecular aggregates (as observed for non-PEGylated peptides), by promoting the formation of micelle-like structures (as demonstrated for valine-based octapeptide). On the other side, the secondary structure of peptides seems not to be affected by PEGylation. Overall, these results suggest that self-assembling behaviour of amphiphilic octapeptides can be modified by PEGylation, with a great potential impact for the future applications of these nanomaterials

Developing a self-healing supramolecular nucleoside hydrogel

Low molecular weight gelator hydrogels provide a viable alternative to traditional polymer based drug delivery platforms, owing to their tunable stability and in most cases inherent biocompatibility. Here we report the first self-healing nucleoside hydrogel using N4-octanoyl-2′-deoxycytidine (0.5% w/v) for drug delivery. The hydrogel's cross-linked nanofibrillar structure, was characterised using oscillatory rheology and confirmed using SEM and TEM imaging. The potential of this gel for drug delivery was explored in vitro using fluorescently labelled tracers. Cell viability assays were conducted using pancreatic cell lines which tolerated the gels well; whilst no adverse effects on the viability or proliferation of cells were observed for fibroblast cell lines

Self-assembly of bioactive peptides, peptide conjugates, and peptide-mimetic materials

Molecular self-assembly is a multi-disciplinary field of research, with potential chemical and biological applications. One of the main driving forces of self-assembly is molecular amphiphilicity, which can drive formation of complex and stable nanostructures. Self-assembling peptide and peptide conjugates have attracted great attention due to their biocompatibility, biodegradability and biofunctionality. Understanding assembly enables the better design of peptide amphiphiles which may form useful and functional nanostructures. This review covers self-assembly of amphiphilic peptides and peptide mimetic materials, as well as their potential applications

Peptide conjugate hydrogelators

Molecular gelators are currently receiving a great deal of attention. These are small molecules which, under the appropriate conditions, assemble in solution to, in the majority of cases, give long fibrillar structures which entangle to form a three-dimensional network. This immobilises the solvent, resulting in a gel. Such gelators have potential application in a number of important areas from drug delivery to tissue engineering. Recently, the use of peptide-conjugates has become prevalent with oligopeptides (from as short as two amino acids in length) conjugated to a polymer, alkyl chain or aromatic group such as naphthalene or fluorenylmethoxycarbonyl (Fmoc) being shown to be effective molecular gelators. The field of gelation is extremely large; here we focus our attention on the use of these peptide-conjugates as molecular hydrogelators

PEG−peptide conjugates

The remarkable diversity of the self-assembly behavior of PEG−peptides is reviewed, including self-assemblies formed by PEG−peptides with β-sheet and α-helical (coiled-coil) peptide sequences. The modes of self-assembly in solution and in the solid state are discussed. Additionally, applications in bionanotechnology and synthetic materials science are summarized

Confined wrinkling of thin elastic rods, sheets and cones

Thin-walled structures, such as plates and shells, become more vulnerable to in-plane compressive effects as their thickness is reduced, where they may buckle out-of-plane at lower than operational loads. Here, a novel approach allows the thin structures to buckle, but within a prescribed confinement to ensure higher-mode buckling and hence a reasonable post-buckling capacity. The main aim is to understand and predict this confined buckling behaviour of some simple thin-walled structural forms: a rod, rectangular sheet, trapezium, rectangle with a central hole, cone and conical frustum. Rods and planar sheets are initially buckled into their first mode by applying a small axial displacement. Confinement is achieved by placing the buckled sheet between two parallel rigid plates, which are gradually moved towards each other until the sheet buckles further. Cones and frusta are confined immediately without initial buckling. Physical experiments and finite element analyses are used to investigate and observe the confined buckling response, as well as to verify the analytical models derived to predict the behaviour. Here it is shown that, as they are confined, the sheets progressively buckle into higher modes, forming more and more sinusoidal waves or wrinkles. Rods and rectangular sheets form straight wrinkles with constant wavelengths. Less regular shapes, such as trapezia and rectangles with a hole, form curved wrinkles with a variable wavelength, which is inversely proportional to the square root of the geometric strain. For all initially planar sheets, wrinkle directions align approximately perpendicularly to free edges. On the other hand, cones form hoop wrinkles with an almost constant wavelength, while frusta form a combination of inner radial and outer hoop wrinkles, with the transition between the two moving closer to the outer edge for larger inner holes. Radial wrinkles at the inner edge have a constant wavelength, which is proportional to the confinement gap between the rigid plates. All structures considered exhibit a variable stiffness, with the load capacity on average increasing exponentially with confinement. The results extend the limited literature on confined buckling and wrinkling, and are part of the first known study to include irregularly shaped confined wrinkled sheets. Direct applications could utilise the variable stiffness of the confined rods and sheets, by setting the confinement gap to achieve a certain stiffness or load carrying capacity.EPSRC (CDT grant, ref: EP/L016095/1) Emmanuel College Scholarship The Cambridge Philosophical Society Research Studentshi

Iridescent coatings from block copolymers : adhesion and fabrication

EThOS - Electronic Theses Online ServiceGBUnited Kingdo