Multilevel approaches applied to the capacitated clustering problem

This paper presents two multilevel refinement algorithms for the capacitated clustering problem. Multilevel refinement is a collaborative technique capable of significantly aiding the solution process for optimisation problems. The central methodologies of the technique are filtering solutions from the search space and reducing the level of problem detail to be considered at each level of the solution process. The first multilevel algorithm uses a simple tabu search while the other executes a standard local search procedure. Both algorithms demonstrate that the multilevel technique is capable of aiding the solution process for this combinatorial optimisation problem.

Back to the bad old days?

Reviews the Court of Appeal decision in James v Thomas that a cohabitee had not acquired an equitable interest in a property registered in her former partner's sole name through a constructive trust, based on express or inferred common intention, or by proprietary estoppel. Highlights the inconsistent approach of the courts to cohabitee disputes. Outlines the Law Commission's proposals in its 2007 report, Cohabitation: The Financial Consequences of Relationship Breakdown, notes the factors to be taken into account by the courts, and speculates on the case's outcome if the proposals were applied. [From Legal Journals Index]

The use of fluorescence microscopy to define polymer localisation to the late endocytic compartments in cells that are targets for drug delivery

Macromolecular therapeutics and nano-sized drug delivery systems often require localisation to specific intracellular compartments. In particular, efficient endosomal escape, retrograde trafficking, or late endocytic/lysosomal activation are often prerequisites for pharmacological activity. The aim of this study was to define a fluorescence microscopy technique able to confirm the localisation of water-soluble polymeric carriers to late endocytic intracellular compartments. Three polymeric carriers of different molecular weight and character were studied: dextrin (Mw~50,000 g/mol), a N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer (Mw approximately 35,000 g/mol) and polyethylene glycol (PEG) (Mw 5000 g/mol). They were labelled with Oregon Green (OG) (0.3-3 wt.%; <3% free OG in respect of total). A panel of relevant target cells were used: THP-1, ARPE-19, and MCF-7 cells, and primary bovine chondrocytes (currently being used to evaluate novel polymer therapeutics) as well as NRK and Vero cells as reference controls. Specific intracellular compartments were marked using either endocytosed physiological standards, Marine Blue (MB) or Texas-red (TxR)-Wheat germ agglutinin (WGA), TxR-Bovine Serum Albumin (BSA), TxR-dextran, ricin holotoxin, C6-7-nitro-2,1,3-benzoxadiazol-4-yl (NBD)-labelled ceramide and TxR-shiga toxin B chain, or post-fixation immuno-staining for early endosomal antigen 1 (EEA1), lysosomal-associated membrane proteins (LAMP-1, Lgp-120 or CD63) or the Golgi marker GM130. Co-localisation with polymer-OG conjugates confirmed transfer to discreet, late endocytic (including lysosomal) compartments in all cells types. The technique described here is a particularly powerful tool as it circumvents fixation artefacts ensuring the retention of water-soluble polymers within the vesicles they occupy.

Experts on e-learning: insights gained from listening to the student voice!

The Student Experience of e-Learning Laboratory (SEEL) project at the University of Greenwich was designed to explore and then implement a number of approaches to investigate learners’ experiences of using technology to support their learning. In this paper members of the SEEL team present initial findings from a University-wide survey of nearly a 1000 students. A selection of 90 ‘cameos’, drawn from the survey data, offer further insights into personal perceptions of e-learning and illustrate the diversity of students experiences. The cameos provide a more coherent picture of individual student experience based on the totality of each person’s responses to the questionnaire. Finally, extracts from follow-up case studies, based on interviews with a small number of students, allow us to ‘hear’ the student voice more clearly. Issues arising from an analysis of the data include student preferences for communication and social networking tools, views on the ‘smartness’ of their tutors’ uses of technology and perceptions of the value of e-learning. A primary finding and the focus of this paper, is that students effectively arrive at their own individualised selection, configuration and use of technologies and software that meets their perceived needs. This ‘personalisation’ does not imply that such configurations are the most efficient, nor does it automatically suggest that effective learning is occurring. SEEL reminds us that learners are individuals, who approach learning both with and without technology in their own distinctive ways. Hearing, understanding and responding to the student voice is fundamental in maximising learning effectiveness. Institutions should consider actively developing the capacity of academic staff to advise students on the usefulness of particular online tools and resources in support of learning and consider the potential benefits of building on what students already use in their everyday lives. Given the widespread perception that students tend to be ‘digital natives’ and academic staff ‘digital immigrants’ (Prensky, 2001), this could represent a considerable cultural challenge.

To the editor of BJLD

[Letter to the editor of BJLD]

Drug calculations part 2: alternative strategies to the formula

Drug calculations are an essential skill for nurses. The clinical skill of performing a drug calculation has come under recent scrutiny,resulting in the development of essential skills clusters inwhich pre-registration nurses must be competent before qualifying (Nursing and Midwifery Council 2007). The focuson drug calculation skills places renewed emphasis on how these skills are taught in higher education institutions and how they are learned by students theoretically and in clinical practice.

The illusions of competition in the water sector: a response to the OFWAT/Cave consultations on introducing competition in the water sector in England and Wales

The paper provides a critical review of the role of liberalisation and competition in the water sector, based on empirical evidence from the UK and internationally. The paper is submitted as evidence to the official reviews of competition in water sector in England and Wales.

Condition assessment of a 63-year old reinforced concrete structure exposed to the North Sea

This paper describes the condition of a reinforced concrete balustrade consisting of some 1000 individual beam elements all exposed similarly to the hostile marine environment of the North Sea at Arbroath, Scotland since 1943. A comparison is made of the condition of the original construction with the condition of repairs carried out in 1968 and in 1993. It is shown that the 1943 construction shows very little corrosion-induced cracking and little rust staining even though it does not appear to be of high construction quality. Only a very low percentage of the balustrade beams have been replaced. In contrast the beam installed in 1968 and later in 1993 show very considerable and large concrete cracks directly attributable to the corrosion of the longitudinal reinforcement, even though the concrete is of a higher quality and density. A detailed condition survey and statistics of crack sizes are presented in the paper. It is found that the higher corrosion resistance of the 1943 concrete is generally consistent with the concrete electrical resistivity measurements but the degree of corrosion of the reinforcing bars is inconsistent with chloride penetration measurements. The results are compared with the very few observations available in the literature for ageing concrete structures in marine environments. The results cast doubt on the conventional wisdom that chloride content at the reinforcement correlates well with reinforcement corrosion.