“Out with the old and in with the new” - A retrospective review of paediatric craniocervical junction fixation: indications, techniques and outcomes

Background: The paediatric craniocervical junction has anatomical, physiological and biomechanical properties that make this region unique to that of the adult spine, vulnerable to injury, and contribute to the complexity of management. Traditionally, on-lay fusion with external Halo immobilisation has been used. Instrumented fusion offers intra-operative reduction and immediate stability. Methods: A retrospective review of a single surgeon’s prospectively maintained database was conducted for all cases of paediatric patients that had undergone a fusion involving the occipito-atlanto-axial region. Case notes were reviewed and a radiological analysis was done. Results: Sixteen patients were managed with on-lay fusion and external immobilisation and twentyseven patients were managed with internal fixation using screw-rod constructs. The fusion rates were 80% and 90.5% respectively. Allograft bone grafting was found to be a significant risk factor for non-union. Conclusion: The screws can be safely and predictably placed as confirmed on radiological follow-up with a high fusion rate and an acceptable complication rate. Uninstrumented onlay fusion with Halo immobilization remains an acceptable alternative. Allograft in the form of bone croutons or demineralised bone matrix is a significant risk factor for non-union and posterior iliac crest graft should be used preferentially

The Effects of Isometric Contractions on Breathing and Pulse Rates in the Performance of a Modified Harvard Step Test

The degree of fitness as ascertained by performance of a modified Harvard Step Test did not increase over controls for isometrically trained individuals. However, improvement over a prior training period was apparent. The breathing rate is probably a satisfactory index of measurement for the Harvard Step Test but needs further elucidation

Variable Neighbourhood Search: A Case Study for a Highly-Constrained Workforce Scheduling Problem

This paper describes a Variable Neighbourhood Search (VNS) combined with simulated annealing to tackle a highly constrained workforce scheduling problem at British Telecommunications plc (BT). A refined greedy algorithm is firstly designed to create an initial solution which meets all hard constraints and satisfies some of the soft constraints. The VNS is then used to swap out less promising combinations, continually moving towards a more optimal solution until meeting finishing requirements. The results are promising when compared to the stand- alone greedy algorithm. We believe there is scope for this to be extended in several ways, i.e. into a more complex variation of VNS to further improve results, to be applied to further data sets and workforce scheduling problem scenarios, and to have input parameters to the algorithm selectively optimized to discover what kind of improvements in efficiency and fitness are possible. There is also scope for this to be used in similar combinatorial optimization problems

A Hybrid Metaheuristic Approach to a Real World Employee Scheduling Problem

Employee scheduling problems are of critical importance to large businesses. These problems are hard to solve due to large numbers of conflicting constraints. While many approaches address a subset of these constraints, there is no single approach for simultaneously addressing all of them. We hybridise 'Evolutionary Ruin & Stochastic Recreate' and 'Variable Neighbourhood Search' metaheuristics to solve a real world instance of the employee scheduling problem to near optimality. We compare this with Simulated Annealing, exploring the algorithm configuration space using the irace software package to ensure fair comparison. The hybrid algorithm generates schedules that reduce unmet demand by over 28% compared to the baseline. All data used, where possible, is either directly from the real world engineer scheduling operation of around 25,000 employees , or synthesised from a related distribution where data is unavailable

Society for Research on Nicotine and Tobacco

The proceedings of the inaugural scientific meeting of the Society for Research on Nicotine and Tobacco (SRNT) are summarized. The primary objective of the meeting was to foster the exchange of information on the effects of nicotine and tobacco use, as well as factors which influence their use, drawing from biological, behavioral and social sciences. Much of this research can be viewed as a tale of two drugs nicotine as a key to an important public health problem, and nicotine as a classical tool of physiological and pharmacological research. A historical overview of research on both drugs is provided first. Public policy alternatives for reducing the prevalence of tobacco use have been derived in part from basic and clinical research results and are briefly outlined. Evidence for genetic determinants on nicotine use and effects is presented using data from twin studies and from molecular genetic research with humans and animals. Consistent with this research, there is evidence of individual differences in pharmacokinetics and effects of nicotine, which could account for differences in smoking behavior and nicotine dependence. Finally, recent developments in the therapeutic uses of nicotine and novel nicotinic agonists with schizophrenia, Alzheimer's disease, Parkinson's disease, Tourette's syndrome and ulcerative colitis are presented. Overall, the research presented at the meeting demonstrated the vast diversity of areas of study involving nicotine and tobacco, as well as the rich opportunities for cross-communication among researchers from different disciplines.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72963/1/j.1360-0443.1996.91112915.x.pd

Modelando las decisiones de un experto a través del aprendizaje basado en decisiones: aplicaciones de la teoría, a la práctica y a la tecnología

In higher education, faculty are generally hired for their expertise in the field. They have received extensive training in the discipline but have received limited training in teaching. Thus, they struggle in two ways to teach and develop expertise in novices: First, they are often blind to how their own intuitive expertise functions, and second, they lack a pedagogical strategy to teach their intuitive expert decision-making to students. In this paper, we synthesize the literature on these difficulties for experts. We then discuss how DBL uses cognitive task analysis to help experts make their knowledge explicit and how DBL may be an appropriate pedagogical solution for many university professors. Finally, we provide case studies of DBL in action and discuss how educational technology can support the theory and practice of Decision-based Learning.En la educación universitaria, se contrata a los profesores generalmente por su habilidad de hacer investigaciones. La mayoría de los profesores han recibido una amplia formación en su especialización, pero no han recibido la capacitación adecuada para compartir su conocimiento con sus alumnos. Por lo tanto, se les hace difícil en dos maneras de enseñar y ayudar a sus alumnos a desarrollar una habilidad experta. En primer lugar, a menudo no saben cómo funciona su propio conocimiento intuitivo y, en segundo lugar, carecen de una estrategia pedagógica para enseñar a los alumnos su proceso de tomar decisiones como expertos. En este artículo, sintetizamos la literatura sobre estas dificultades para expertos. Luego, explicamos cómo el Aprendizaje Basado en Decisiones (ABD) usa el análisis de tareas cognitivas para ayudar a los expertos a que hagan explícito su conocimiento. Además, explicamos cómo ABD puede ser una solución pedagógica apropiada para muchos profesores universitarios. Para concluir, hemos proporcionado estudios de caso donde nosotros y otros hemos usado ABD y explicamos cómo la tecnología educativa puede apoyar la teoría y la práctica del aprendizaje basado en decisiones

Ether in the developing world: rethinking an abandoned agent.

BACKGROUND: The first true demonstration of ether as an inhalation anesthetic was on October 16, 1846 by William T.G. Morton, a Boston dentist. Ether has been replaced completely by newer inhalation agents and open drop delivery systems have been exchanged for complicated vaporizers and monitoring systems. Anesthesia in the developing world, however, where lack of financial stability has halted the development of the field, still closely resembles primitive anesthetics. DISCUSSION: In areas where resources are scarce, patients are often not given supplemental intraoperative analgesia. While halothane provides little analgesia, ether provides excellent intra-operative pain control that can extend for several hours into the postoperative period. An important barrier to the widespread use of ether is availability. With decreasing demand, production of the inexpensive inhalation agent has fallen. Ether is inexpensive to manufacture, and encouraging increased production at a local level would help developing nations to cut costs and become more self-sufficient

Shift Scheduling and Employee Rostering: An Evolutionary Ruin & Stochastic Recreate Solution

For decades, since the inception of the field, scheduling problems have been solved with a variety of techniques. Many proven algorithms to these problems exist; however, there is no single method to solve all the vast variety of problems that exist across many sub-fields with differing datasets. In this paper we explore the use of an Evolutionary Ruin & Stochastic Recreate algorithm, with a Simulated Annealing control mechanism, to a real-world employee scheduling problem and its ability to solve this problem to near optimality. The combinatorial possibilities of parameterisation are very large-the Taguchi design of experiments method is used to examine a subset of those possibilities within a limited runtime budget. Evolutionary Ruin and Stochastic Recreate has not previously been applied to the specific scheduling domain of employee scheduling and rostering: we investigate the effectiveness of the algorithm with different parameter values and discuss the insight it provides into the runtime effect of the mechanisms of Evolutionary Ruin & Stochastic Recreate