Teachers’ beliefs about assessment and accountability

One of the main aims of national assessment programmes is to improve the efficacy of education systems; realizing this aim often takes the form of implementing a variety of accountability measures. Using assessment results for accountability purposes is highly controversial, while one of its undesirable impacts is that it generates negative attitudes towards educational assessments among teachers. The aim of this study is to examine lower and upper secondary teachers’ ( N = 1552) opinions and beliefs about testing and, more specifically, about the national assessment programme in Hungary. A questionnaire was used to explore teachers’ beliefs about the effects of the assessment system on how they teach, perceived pressure from stakeholders, teachers’ acceptance of assessment programmes and the relationship between these beliefs. Results show that assessment programmes compel teachers to revise their teaching practices — some change to make meaningful gains in student learning, while others turn to practices that are not conducive to a genuine improvement in students’ knowledge, focussing instead on assessment scores. Pressure from inside the school (colleagues and school leaders) and teachers’ attitude towards assessments bring about changes in instruction, such as the reallocation of coaching and improvement in teaching. Sources of pressure outside school (local government and the media) have an indirect effect on changes in teaching because their pressure influences in-school motivators. Pressure from parents and students is felt directly by teachers, but only in limited areas. The results demonstrate that a national assessment programme has a more significant impact on teaching in lower than in upper secondary schools

Core-Shell Structured PLGA Particles Having Highly Controllable Ketoprofen Drug Release

The non-steroid anti-inflammatory drug ketoprofen (KP) as a model molecule is encapsulated in different poly(lactide-co-glycolide) (PLGA) nanostructured particles, using Tween20 (TWEEN) and Pluronic F127 (PLUR) as stabilizers to demonstrate the design of a biocompatible colloidal carrier particles with highly controllable drug release feature. Based on TEM images the formation of well-defined core-shell structure is highly favorable using nanoprecipitation method. Stabile polymer-based colloids with ~200–210 nm hydrodynamic diameter can be formed by successful optimization of the KP concentration with the right choice of stabilizer. Encapsulation efficiency (EE%) of 14–18% can be achieved. We clearly confirmed that the molecular weight of the stabilizer thus its structure greatly controls the drug release from the PLGA carrier particles. It can be determined that ~20% and ~70% retention is available with the use of PLUR and TWEEN, respectively. This measurable difference can be explained by the fact that the non-ionic PLUR polymer provides a steric stabilization of the carrier particles in the form of a loose shell, while the adsorption of the non-ionic biocompatible TWEEN surfactant results in a more compact and well-ordered shell around the PLGA particles. In addition, the release property can be further tuned by decreasing the hydrophilicity of PLGA by changing the monomer ratio in the range of ~20–60% (PLUR) and 70–90% (TWEEN)

The Effect of Concentration, Temperature, and pH on the Formation of Hyaluronic Acid–Surfactant Nanohydrogels

The assembly of colloidal hyaluronic acid (HyA, as a polysaccharide) based hydrogel particles in an aqueous medium is characterized in the present paper, with an emphasis on the particular case of nanohydrogels formed by surfactant-neutralized polysaccharide networks. The structural changes and particle formation process of polysaccharide- and cationic-surfactant-containing systems were induced by the charge neutralization ability and the hydrophobic interactions of cetyltrimethylammonium bromide (CTAB) under different conditions. Based on the rheological, light scattering, ζ-potential, turbidity, and charge titration measurements, it can be concluded that the preparation of the HyA-CTAB particles can be greatly controlled. The results indicate that more available negative charges can be detected on the polymer chain at smaller initial amounts of HyA (cHyA < 0.10 mg/mL), where a molecular solution can be formed. The change in the pH has a negligible effect on the formation process (particle aggregation appears at nCTAB/nHyA,monomer~1.0 in every case), while the temperature dependence of the critical micelle concentration (c.m.c.) of CTAB determines the complete neutralization of the forming nanohydrogels. The results of our measurements confirm that after the appearance of stable colloidal particles, a structural change and aggregation of the polymer particles take place, and finally the complete charge neutralization of the system occurs