Recent advances in spin crossover research

Thermal spin transition (spin crossover), one of the most fascinating dynamic electronic structure phenomena occurring in coordination compounds of third row transition metal ions, mostly of iron(II), iron(III) and cobalt(II) with critical ligand field strengths competing with the spin pairing energy, has attracted increasing attention by many research groups. One of the reasons is the promising potential for practical applications. In this chapter we intend to cover essential recent work, primarily accomplished within the European research network on “Thermal and Optical Switching of Molecular Spin States (TOSS)”. New spin crossover compounds and their thermal spin transition behaviour, also under applied pressure, novel effects observed by irradiation and magnetic field, will be discussed. Progress in theoretical treatments of spin crossover phenomena, particularly cooperativity, will be briefly outlined. The chapter concludes with a summary of research highlights published by the partner laboratories of the TMR network TOSS.

Molecular modelling assisted design and synthesis of cyclothialidine derivatives as DNA gyrase inhibitors

Since cyclothialidine was discovered as the most active DNA gyrase inhibitor in 1994, enormous efforts have been devoted to make it into a commercial medicine by a number of pharmaceutical companies and research groups worldwide. However, no serious breakthrough has been made up to now. An essential problem involved with cyclothialidine is that though it demonstrated the potent inhibition of DNA gyrase, it showed little activity against bacteria. This probably is attributable to its inability to penetrate bacterial cell walls and membranes. We applied the TSAR programme to generate a QSAR equation to the gram-negative organisms. In that equation, LogP is profoundly indicated as the key factor influencing the cyclothialidine activity against bacteria. However, the synthesized new analogues have failed to prove that. In the structure based drug design stage, we designed a group of open chain cyclothialidine derivatives by applying the SPROUT programme and completed the syntheses. Improved activity is found in a few analogues and a 3D pharmacophore of the DNA gyrase B is proposed to lead to synthesis of the new derivatives for development of potent antibiotics.

Ultra-long mode-locked Er-droped fibre lasers

The development of ultra-long (UL) cavity (hundreds of meters to several kilometres) mode-locked fibre lasers for the generation of high-energy light pulses with relatively low (sub-megahertz) repetition rates has emerged as a new rapidly advancing area of laser physics. The first demonstration of high pulse energy laser of this type was followed by a number of publications from many research groups on long-cavity Ytterbium and Erbium lasers featuring a variety of configurations with rather different mode-locked operations. The substantial interest to this new approach is stimulated both by non-trivial underlying physics and by the potential of high pulse energy laser sources with unique parameters for a range of applications in industry, bio-medicine, metrology and telecommunications. It is well known, that pulse generation regimes in mode-locked fibre lasers are determined by the intra-cavity balance between the effects of dispersion and non-linearity, and the processes of energy attenuation and amplification. The highest per-pulse energy has been achieved in normal-dispersion UL fibre lasers mode-locked through nonlinear polarization evolution (NPE) for self-modelocking operation. In such lasers are generated the so-called dissipative optical solitons. The uncompensated net normal dispersion in long-cavity resonatorsusually leads to very high chirp and, consequently, to a relatively long duration of generated pulses. This thesis presents the results of research Er-doped ultra-long (more than 1 km cavity length) fibre lasers mode-locked based on NPE. The self-mode-locked erbium-based 3.5-km-long all-fiber laser with the 1.7 µJ pulse energy at a wavelength of 1.55 µm was developed as a part of this research. It has resulted in direct generation of short laser pulses with an ultralow repetition rate of 35.1 kHz. The laser cavity has net normal-dispersion and has been fabricated from commercially-available telecom fibers and optical-fiber elements. Its unconventional linear-ring design with compensation for polarization instability ensures high reliability of the self-mode-locking operation, despite the use of a non polarization-maintaining fibers. The single pulse generation regime in all-fibre erbium mode-locking laser based on NPE with a record cavity length of 25 km was demonstrated. Modelocked lasers with such a long cavity have never been studied before. Our result shows a feasibility of stable mode-locked operation even for an ultra-long cavity length. A new design of fibre laser cavity – “y-configuration”, that offers a range of new functionalities for optimization and stabilization of mode-locked lasing regimes was proposed. This novel cavity configuration has been successfully implemented into a long-cavity normal-dispersion self-mode-locked Er-fibre laser. In particular, it features compensation for polarization instability, suppression of ASE, reduction of pulse duration, prevention of in-cavity wave breaking, and stabilization of the lasing wavelength. This laser along with a specially designed double-pass EDFA have allowed us to demonstrate anenvironmentally stable all-fibre laser system able to deliver sub-nanosecond high-energy pulses with low level of ASE noise.

Retinal vessel analysis:flicker reproducibility, methodological standardisations and practical limitations

The Retinal Vessel Analyser (RVA) is a commercially available ophthalmoscopic instrument capable of acquiring vessel diameter fluctuations in real time and in high temporal resolution. Visual stimulation by means of flickering light is a unique exploration tool of neurovascular coupling in the human retina. Vessel reactivity as mediated by local vascular endothelial vasodilators and vasoconstrictors can be assessed non-invasively, in vivo. In brief, the work in this thesis • deals with interobserver and intraobserver reproducibility of the flicker responses in healthy volunteers • explains the superiority of individually analysed reactivity parameters over vendorgenerated output • links in static retinal measures with dynamic ones • highlights practical limitations in the use of the RVA that may undermine its clinical usefulness • provides recommendations for standardising measurements in terms of vessel location and vessel segment length and • presents three case reports of essential hypertensives in a -year follow-up. Strict standardisation of measurement procedures is a necessity when utilising the RVA system. Agreement between research groups on implemented protocols needs to be met, before it could be considered a clinically useful tool in detecting or predicting microvascular dysfunction.

Optical spectral broadening and supercontinuum generation in telecom applications

We overview the recent development in applications of spectral broadening and supercontinuum generation in the field of optical communications. Special attention is dedicated to recent results obtained in our research groups. © 2005 Elsevier Inc. All rights reserved.

Changes at the BCLA

As we welcome 2014 we say goodbye to 2013 and I must start with an apology to authors who have submitted papers to CLAE and seen a delay in either the review process or the hard copy publication of their proofed article. The delays were caused by a major hike in the number of submissions to the journal in 2012 that increased further in 2013. In the 12 months leading to the end of October 2011 we had 94 new paper submissions, and for the same period to the end of 2012 the journal had 116 new papers. In 2012 we were awarded an impact factor for the first time and following that the next 12 month period to the end of October 2013 saw a massive increase in submissions with 171 new manuscripts being submitted. This is nearly twice as many papers as 2 years ago and 3 times as many as when I took over as Editor-in-Chief. In addition to this the UK academics will know that 2014 is a REF year (Research Excellence Framework) where universities are judged on their research and one of the major components of this measure remains to be published papers so there is a push to publishing before the REF deadline for counting. The rejection rate at CLAE has gone up too and currently is around 50% (more than double the rejection rate when I took over as Editor-in-Chief). At CLAE the number of pages that we publish each year has remained the same since 2007. When compiling issue 1 for 2014 I chose the papers to be included from the papers that were proofed and ready to go and there were around 200 proofed pages ready, which is enough to fill 3½ issues! At present Elsevier and the BCLA are preparing to increase the number the pages published per issue so that we can clear some of this backlog and remain up to date with the papers published in CLAE. I should add that on line publishing of papers is still available and there may have been review delays but there are no publishing online so authors can still get an epub on line final version of their paper with a DOI (digital object identifier) number enabling the paper to be cited. There are two awards that were made in 2013 that I would like to make special mention of. One was for my good friend Jan Bergmanson, who was awarded an honorary life fellowship of the College of Optometrists. Jan has served on the editorial board of CLAE for many years and in 2013 also celebrated 30 years of his annual ‘Texan Corneal and contact lens meeting’. The other award I wish to mention is Judith Morris, who was the BCLA Gold Medal Award winner in 2013. Judith has had many roles in her career and worked at Moorfields Eye Hospital, the Institute of Optometry and currently at City University. She has been the Europe Middle East and Africa President of IACLE (International Association of Contact Lens Educators) for many years and I think I am correct in saying that Judith is the only person who was President of both the BCLA (1983) and a few years later she was the President College of Optometrists (1989). Judith was also instrumental in introducing Vivien Freeman to the BCLA as they had been friends and Judith suggested that Vivien apply for an administrative job at the BCLA. Fast forward 29 years and in December 2013 Vivien stepped down as Secretary General of the BCLA. I would like to offer my own personal thanks to Vivien for her support of CLAE and of me over the years. The BCLA will not be the same and I wish you well in your future plans. But 2014 brings in a new position to the BCLA – Cheryl Donnelly has been given the new role of Chief Executive Officer. Cheryl was President of the BCLA in 2000 and has previously served on council. I look forward to working with Cheryl and envisage a bright future for the BCLA and CLAE. In this issue we have some great papers including some from authors who have not published with CLAE before. There is a nice paper on contact lens compliance in Nepal which brings home some familiar messages from an emerging market. A paper on how corneal curvature is affected by the use of hydrogel lenses is useful when advising patients how long they should leave their contact lenses out for to avoid seeing changes in refraction or curvature. This is useful information when refracting these patients or pre-laser surgery. There is a useful paper offering tips on fitting bitoric gas permeable lenses post corneal graft and a paper detailing surgery to implant piggyback multifocal intraocular lenses. One fact that I noted from the selection of papers in the current issue is where they were from. In this issue none of the corresponding authors are from the United Kingdom. There are two papers each from the United States, Spain and Iran, and one each from the Netherlands, Ireland, Republic of Korea, Australia and Hong Kong. This is an obvious reflection of the widening interest in CLAE and the BCLA and indicates the new research groups emerging in the field.

Mode-locked semiconductor disk lasers

This paper will review the recent advances in the field of ultrashort pulse generation from optically pumped vertical-external-cavity surface-emitting lasers (OP-VECSELs). In this review, we will summarize the most significant results presented over the last 15 years, before highlighting recent breakthroughs related to mode-locked VECSELs by different research groups. Different mode-locking techniques for OP-VECSELs are described in detail. Previously, saturable absorbers, such as semiconductor saturable absorber mirrors—external, or internal as in mode-locked integrated external-cavity surface emitting lasers (MIXSEL)—, and recently, novel-material-based carbon-nanotube and graphene saturable absorbers have been employed. A new mode-locking method was presented and discussed in recent years. This method is referred to as self-mode-locking or saturable-absorber-free operation of mode-locked VECSELs. In this context, we particularly focus on achievements regarding self-mode-locking, which is considered a promising technique for the realization of high-power, compact, robust and cost-efficient ultrashort pulse lasers. To date, the presented mode-locking techniques have led to great enhancement in average powers, peak powers, and repetition rates that can be achieved with passively mode-locked VECSELs.

Finding natural groups in data:an application to strategic group research

The best way of finding “natural groups” in management research remains subject to debate and within the literature there is no accepted consensus. The principle motivation behind this study is to explore the effect of choices of method upon strategic group research, an area that has suffered enduring criticism, as we believe that these method choices are still not fully exploited. Our study is novel in the use of a variety of more robust clustering and validation techniques, rarely used in management research, some borrowed from the natural sciences, which may provide a useful and more robust base for this type of research. Our results confirm that methods do exist to address the concerns over strategic group research and adoption of our chosen methods will improve the quality of management research.

Impact of the length of relationships upon the use of research institutes by SMEs

Recent studies of US industrial modernisation programmes argue that difficulties of establishing long-term relationships with users prevent them from facilitating development of innovation capabilities. The paper supports this argument through a survey of Japanese research institutes the US programmes were modelled on. In view of information asymmetries in their use, it tests the hypothesis that small and medium-sized firms start using the research institutes with ‘low information gap’ services and gradually move on to ‘high information gap’ services that often require more absorptive capacity. This is demonstrated both under one-to-one relationships and between groups of firms and a research institute.

Images of pharmacy as a career: a survey among groups of year 12 students at school

To explore the images and perceptions of pharmacy with potential applicants to undergraduate pharmacy education. There is currently considerable interest in the UK in studying aspects of the pharmacy profession because of the changing pharmacy agenda and the need to understand the workforce and its motivations. Aim: To explore the images and perceptions of pharmacy with potential applicants to undergraduate pharmacy education. Design: Four interactive focus groups involving 40 volunteer year 12 students (age 17). The focus group theme plan was designed after a review of relevant literature. A novel approach was employed using photographic images of pharmacists and doctors in varied settings. Subjects and setting: The research was carried out in six schools in the West Midlands, UK. Results: The students presented a rather negative image of pharmacy as a boring occupation in a laboratory or the back of a shop. Most had little idea of what pharmacists actually do. Unlike nursing, they were unaware of positive role models in the media. The small number who did have a realistic idea of pharmacy based it on their previous work experience in pharmacy. Conclusions: The focus group technique is useful for exploring hitherto untapped perceptions of the profession. Undertaking research with year 12 students provided some useful insights into the ways in which pharmacy as a profession is perceived. Although no claims to generalisability are made here, the results were fed into the design of quantitative surveys. The somewhat negative image presented suggests that the profession has more work to do in marketing itself to young people as a potential career choice.

Strategic groups, competitive groups and performance within the U.K. pharmaceutical industry:Improving our understanding of the competitive process

Strategic group research originated in the 1970s and a number of notable studies centered on the U.S. pharmaceutical industry. Results were, however, conflicting. This paper explores the nature of strategic groups in the U.K. pharmaceutical industry. The study confirms the presence of between six and eight strategic groups across the period studied, 1998-2002. The study also demonstrates a statistically significant relationship between these strategic groups and performance using three performance measures. The paper then compares strategic groups with competitive groups and concludes that the distinction is important and may explain the contradictory findings in earlier strategic group research. Copyright © 2007 John Wiley & Sons, Ltd.

Programmatic efficiency comparisons between unequally sized groups of DMUs in DEA

Data envelopment analysis (DEA) is a popular non-parametric technique for determining the efficiency of a homogeneous set of decision-making units (DMUs). In many practical cases, there is some doubt if the all the DMUs form a single group with a common efficiency distribution. The Mann-Whitney rank statistic has been used in DEA both to test if two groups of DMUs come from a common efficiency distribution and also to test if the two groups have a common frontier, each of which are likely to have important but different policy implications for the management of the groups. In this paper it is demonstrated that where the Mann-Whitney rank statistic is used for the second of these it is likely to overestimate programmatic inefficiency, particularly of the smaller group. A new non-parametric statistic is proposed for the case of comparing the efficient frontiers of two groups, which overcomes the problems we identify in the use of the Mann-Whitney rank statistic for this purpose. © 2005 Operational Research Society Ltd. All rights reserved.

The Team Climate Inventory (TCI): a psychometric test on a Taiwanese sample of work groups

Understanding the feasibility of applying the Team Climate Inventory (TCI) in non-Western cultures is essential for researchers attempting to understand the influence of culture on workers' perceived climate. This study describes the application of the TCI in such a setting using data from 203 administrators employed in a Taiwanese medical center. Reliability and factor analyses were performed to establish the feasibility and psychometric properties of the TCI Taiwan version. Reliabilities of both the four- and five-factor solutions exceeded .80. Factor analyses indicated a satisfactory four-factor structure, despite some variations in comparison with the U.K. version. The TCI Taiwan version is feasible and has acceptable psychometric properties. Further research is warranted regarding the degree to which disparities result from cultural differences and the specific nature of organizational systems in Chinese communities.