Explaining the success of the world's leading education systems: the case of Singapore

International comparative data on student performance has led McKinsey & Company, among others, to suggest that education systems will inexorably converge in their developmental trajectories with principals and schools enjoying more autonomy. This article challenges these assumptions through referencing Singapore where schools and professionals are still tightly controlled in key resources, curricula and assessment, and where other key factors contribute to its success – thereby evidencing multiple pathways to success

Re-conceptualising learning-centred (instructional) leadership: an obsolete concept in need of renovation

For more than thirty years, ‘instructional leadership’ has been at the forefront of research and practice in school effectiveness and improvement. Governments, employers, universities and professional developers, all see it as a mainstay of raising school and student performance. Wave-after-wave of educational policy reforms during this period have changed school environments, widening and deepening the (instructional) leadership roles and functions of principals and other school leaders. Terminology has changed – while Americans still use ‘instructional leadership’, others prefer ‘learning-centred’ and ‘leadership-for -learning’, disputing whether they encompass the same or different meanings. Yet curiously, the concept itself – as defined and measured by academic researchers and scholars - has changed relatively little since Hallinger and Murphy’s first seminal contribution in 1985. This paper argues the case for wholesale renovation of the concept if it is to maintain relevance going forward. The case is supported by important and powerful trends in policy and practice

A note on the solution of regular PMDs

A new resolvent decomposition of a regular polynomial matrix is derived which is a refinement of the results given by Gohberg et al (1982) and Vardulakis (1991). Based on this, a complete solution of the regular Polynomial Matrix Descriptions (PMDs) is presented that reflects precisely the zero input response and the zero state response, and takes into account the impulsive properties of the system. An algorithm for the computation of this resolvent decomposition is provided

Spectral structures of the generalized companion form and applications

In this note, we investigate the relationship between the finite and infinite frequency structure of a regular polynomial matrix and that of a particular linearization, called the generalised companion matrix. A special resolvent decomposition of the regular polynomial matrix is proposed which is based on the Weierstrass canonical form of this generalised companion matrix and the solution of a regular PMD is thus formulated from this resolvent decomposition. Both the initial conditions of the pseudo state and the input are considered

Antifungal and mucoadhesive properties of an orally administered chitosan-coated amphotericin B 1 nanostructured lipid carrier (NLC)

Surface - modified nanostructured lipid carriers (NLC) is a promising formulation to prolong the retention time of the therapeutic agent at the site of absorption. Chitosan-coated AmpB-loaded NLC (ChiAmpB NLC) were developed showing particle size of 394.4 ± 6.4 nm, encapsulation efficiency of 86.0 ± 0.3 % and a drug loading of 11.0 ± 0.1 %. ChiAmpB NLC showed biphasic release behaviour with no significant change in its physical properties upon exposure to conditions simulating the gastrointestinal tract. Compared to pure AmpB, ChiAmpB NLC observed not only a comparable antifungal behaviour but showed superior safety profiles, with two times lesser toxicity to the red blood cells and ten times safer to the HT-29 cell line. It was also successfully observed a translation of the in vitro mucoadhesion result to the ex vivo animal study in which ChiAmpB NLC results in higher percentage of retention in the small intestine compared to uncoated formulation. Together, the data strongly offered the possibility of having a non-toxic yet effective oral treatment for systemic fungal infections

Mucoadhesive chitosan-coated nanostructured lipid carriers for oral delivery of amphotericin B

This study describes the properties of an amphotericin B-containing mucoadhesive nanostructured lipid carrier (NLC), with the intent to maximize uptake within the gastrointestinal tract. We have reported previously that lipid nanoparticles can significantly improve the oral bioavailability of amphotericin B (AmpB). On the other hand, the aggregation state of AmpB within the NLC has been ascribed to some of the side effects resulting from IV administration. In the undissolved state, AmpB (UAmpB) exhibited the safer monomeric conformation in contrast to AmpB in the dissolved state (DAmpB), which was aggregated. Chitosan-coated NLC (ChiAmpB NLC) presented a slightly slower AmpB release profile as compared to the uncoated formulation, achieving 26.1 % release in 5 hours. Furthermore, the ChiAmpB NLC formulation appeared to prevent the expulsion of AmpB upon exposure to simulated gastrointestinal pH media, whereby up to 63.9 % of AmpB was retained in the NLC compared to 56.1 % in the uncoated formulation. The ChiAmpB NLC demonstrated mucoadhesive properties in pH 5.8 and 6.8. Thus, the ChiAmpB NLC formulation is well-primed for pharmacokinetic studies to investigate whether delayed gastrointestinal transit may be exploited to improve the systemic bioavailability of AmpB, whilst simultaneously addressing the side-effect concerns of AmpB

Realizations of behavior for generalized chain-scattering representations

This paper introduces a notion of realization of behavior which is shown to be a generalization of the classical concept of a realization of transfer function. By using this approach, the input-output structures of the generalized chain-scattering representations (GCSRs) and the dual generalized chain-scattering representations (DGCSRs) are investigated in a behavioral theory context. Subsequently the corresponding autoregressivemoving- average (ARMA) representations are proposed and are proved to be realizations of behavior for any GCSR. Realization of behavior is particularly suitable for situations in which the coefficients are symbolic rather than numerical due to the fact that no numerical computation is involved in this approach

Reviews

Europe In the Round CD‐ROM, Guildford, Vocational Technologies, 1994

How school leadership practices relate to student outcomes: Insights from a three-level meta-analysis

The present study aims to generate broad insights from the large corpus of literature on the associations between a comprehensive range of school leadership practices and student outcomes in different school contexts. Three-level meta-analysis of 493 independent effects from 108 studies published since 2000 showed that the mean effect size was small at r  = 0.14. Effect sizes for leadership practices ranged from r’s  = 0.10 to .26. Results underscored the importance of different types of leadership practices related to instructional management, enhancing teacher capacity, and engaging external stakeholders to improve student outcomes. School leadership practices were significantly associated with students’ academic achievement (in different subjects except science) and learning attitudes/processes but not attainment. Moderator analyses showed that school leadership effects were significant in studies using a school-level analysis but not in those using a lower-level of analysis. Additionally, school leadership effects were significant at different grade levels (G1–G6, G7–G12) and in research reported in different study types (articles, dissertations) and in different years (2000–2009, 2010–2018)

Pharmacokinetics and tissue distribution of an orally administered mucoadhesive chitosan-coated amphotericin B-Loaded nanostructured lipid carrier (NLC) in rats

© 2019 Informa UK Limited, trading as Taylor & Francis Group. Oral delivery of amphotericin B (AmpB) is desirable because it provides a more patient-friendly mode of administration compared to the current delivery approach akin with the marketed AmpB formulations. The goal of the study was to investigate the pharmacokinetics and tissue distribution of orally administered chitosan-coated AmpB-loaded nanostructured lipid carriers (ChiAmpB NLC) administered to Sprague Dawley rats at a dose of 15 mg/kg. Orally administered ChiAmpB NLC resulted in a two-fold increase in the area under the curve (AUC0-∞) compared to the uncoated AmpB NLC and marketed Amphotret®. This enhanced bioavailability of AmpB suggests prolonged transit and retention of ChiAmpB NLC within the small intestine through mucoadhesion and subsequent absorption by the lymphatic pathway. The results show that mean absorption and residence times (MAT & MRT) were significantly higher from ChiAmpB NLC compared to the other two formulations, attesting to the mucoadhesive effect. The ChiAmpB NLC presented a lower nephrotic accumulation with preferential deposition in liver and spleen. Thus, the limitations of current marketed IV formulations of AmpB are potentially addressed with the ChiAmpB NLC in addition to utilizing this approach for targeting internal organs in visceral leishmaniasis