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Selected AbstractsThe First Anionic Thia-Fries Rearrangements at Ferrocene: Ready Access to Trifluoromethylsulfonyl-Substituted Hydroxyferrocenes and an Extremely High Interannular Stereoinduction between Cyclopentadienyl LigandsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 8 2010Georg Werner Abstract Attempts originally directed towards the generation of ferrocyne (1,2-dehydroferrocene, 4) and ferrocenediyne (1,2,1,,2,-tetradehydroferrocene, 5) by triflate elimination from the respective ferrocenyl triflates led to the discovery of the first anionic thia-Fries rearrangements at a five-membered ring. These reactions take place with remarkable efficiency under very mild reaction conditions and yield the respective trifluoromethylsulfonyl-substituted ferrocenols. Most remarkably, the reaction starting from 1,1,-ferrocenediyl ditriflate (9) adopts an extremely high interannular stereoinduction in that exclusively the meso rearrangement product, meso -2,2,-bis(trifluoromethylsulfonyl)-1,1,-ferrocenediol (16), is formed, the corresponding racemic product 17 is not observed. It is shown that the second anionic thia-Fries rearrangement proceeds at a much larger rate than the first one. The stereochemistry and the high rate of this reaction are explained on the basis of electronic as well as steric considerations. The redox behavior of some of the unprecedented ferrocene derivatives has been characterized by cyclovoltammetry. [source] ChemInform Abstract: Bromination of 5-Methoxyindane: Synthesis of New Benzoindenone Derivatives and Ready Access to 7H-Benzo[c]fluoren-7-one Skeleton.CHEMINFORM, Issue 38 2008Ahmet Tutar Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Stereocontrolled Intramolecular Aziridination of Glycals: Ready Access to Aminoglycosides and Mechanistic Insights from DFT StudiesCHEMISTRY - A EUROPEAN JOURNAL, Issue 5 2008Rujee Lorpitthaya Abstract Stereocontrolled intramolecular aziridination of the glycal-derived sulfamates offers a highly efficient strategy to divergently prepare aminoglycosides. Rhodium-catalyzed nitrogen-atom transfer to CC bonds formed semistable aziridines, which were subjected to various nucleophiles (C, O, S, and N) to give cyclic sulfamate-containing aminosugar derivatives selectively. The second nucleophilic displacement of sulfonyloxy moieties of [1,2,3]-oxathiazepane-2,2- dioxides allows straightforward access to aminoglycosides with selective ,- or ,-linkages. This approach is operationally simple, complements existing methods, and is a versatile protocol for the synthesis of polyfunctionalized amino sugars. In addition, the mechanism of the rhodium-catalyzed intramolecular aziridination of glycals and its ring-opening reaction was extensively studied by using DFT calculations. [source] Teaching Evidence-based Medicine to Medical StudentsACADEMIC EMERGENCY MEDICINE, Issue 12 2004Richard B. Ismach MD Evidence-based medicine (EBM) is the rubric for an approach to learning and practicing medicine that applies skills from clinical epidemiology, library science, and information management to clinical practice. Teaching EBM effectively requires a longitudinal approach throughout medical education. This presents many opportunities for academic emergency physicians, especially in the setting of an emergency medicine clerkship. EBM is best taught at the bedside, although this depends on a skilled and interested faculty. Bedside teaching of EBM also requires ready access to modern information resources. Other venues for teaching EBM include morning report, teaching conferences, and journal clubs. Many tools can be used to aid the process, including Web-based sources such as UpToDate, textbooks, and Web-based tutorials, educational prescriptions, and critically appraised topics. [source] Student perspectives and opinions on their experience at an undergraduate outreach dental teaching centre at Cardiff: a 5-year studyEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 1 2010C. D. Lynch Abstract Aim:, Outreach teaching is now regarded as a desirable component of undergraduate dental teaching programmes in the UK. A purpose-built undergraduate dental outreach-training centre was opened in Cardiff in 2002. The aim of this paper is to report student perspectives and opinions on their experience at this unit over a 5-year period. Methods:, Final year dental students at Cardiff University were invited to report their comments on the St David's Primary Care Unit at various times during their placement there. Information was recorded for undergraduate students who commenced final year in 2003, 2004, 2005, 2006 and 2007 (n = 257). Results:, After 1 year, the most common favourable aspects reported by students included the availability of a suitably trained nurse for all procedures (n = 191), ready access to helpful/approachable teaching staff (n = 145), and closeness of learning experience to subsequent practice (n = 122). Many students commented on their growing confidence in their own abilities whilst in the unit. Conclusion:, Overwhelmingly, students reported their enthusiasm for training in an outreach teaching unit, preferring it to traditional dental school environments. Inherent in the comments recorded for each student was a sense of growing confidence in their abilities and development of reflective practice. Further work is needed to identify the impact of this form of dental student training on subsequent practices in Vocational Training and independent clinical careers. [source] A pilot study comparing the effectiveness of conventional training and virtual reality simulation in the skills acquisition of junior dental studentsEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 1 2003Frank Quinn The use of virtual reality (VR) in the training of operative dentistry is a recent innovation and little research has been published on its efficacy compared to conventional training methods. To evaluate possible benefits, junior undergraduate dental students were randomly assigned to one of three groups: group 1 as taught by conventional means only; group 2 as trained by conventional means combined with VR repetition and reinforcement (with access to a human instructor for operative advice); and group 3 as trained by conventional means combined with VR repetition and reinforcement, but without instructor evaluation/advice, which was only supplied via the VR-associated software. At the end of the research period, all groups executed two class 1 preparations that were evaluated blindly by ,expert' trainers, under traditional criteria (outline, retention, smoothness, depth, wall angulation and cavity margin index). Analyses of resulting scores indicated a lack of significant differences between the three groups except for scores for the category of ,outline form', for group 2, which produced significantly lower (i.e. better) scores than the conventionally trained group. A statistical comparison between scores from two ,expert' examiners indicated lack of agreement, despite identical written and visual criteria being used for evaluation by both. Both examiners, however, generally showed similar trends in evaluation. An anonymous questionnaire suggested that students recognized the benefits of VR training (e.g. ready access to assessment, error identification and how they can be corrected), but the majority felt that it would not replace conventional training methods (95%), although participants recognized the potential for development of VR systems in dentistry. The most common reasons cited for the preference of conventional training were excessive critical feedback (55%), lack of personal contact (50%) and technical hardware difficulties (20%) associated with VR-based training. [source] Stereodefined Access to 3-Deoxy Sugars Through a Tandem Baylis,Hillman and Lewis Acid Catalyzed Reaction SequenceEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 5 2010Palakodety Radha Krishna Abstract An innovative synthetic protocol is reported for the ready access to 3-deoxy sugars in both D and L forms as exclusive products (des >95,%) in high yields through a stereodefined Lewis acid catalyzed reaction sequence of the sugar-derived Baylis,Hillman adducts. [source] Photocrosslinkable Polythiophenes for Efficient, Thermally Stable, Organic PhotovoltaicsADVANCED FUNCTIONAL MATERIALS, Issue 14 2009Bumjoon J. Kim Abstract Photocrosslinkable bromine-functionalized poly(3-hexylthiophene) (P3HT-Br) copolymers designed for application in solution-processed organic photovoltaics are prepared by copolymerization of 2-bromo-3-(6-bromohexyl) thiophene and 2-bromo-3-hexylthiophene. The monomer ratio is carefully controlled to achieve a UV photocrosslinkable layer while retaining the ,,, stacking feature of the conjugated polymers. The new materials are used as electron donors in both bulk heterojunction (BHJ) and bilayer type photovoltaic devices. Unlike devices prepared from either P3HT:PCBM blend or P3HT-Br:PCBM blend without UV treatment, photocrosslinked P3HT-Br:PCBM devices are stable even when annealed for two days at the elevated temperature of 150,°C as the nanophase separated morphology of the bulk heterojunction is stabilized as confirmed by optical microscopy and grazing incidence wide angle X-ray scattering (GIWAXS). When applied to solution-processed bilayer devices, the photocrosslinkable materials show high power conversion efficiencies (,2%) and excellent thermal stability (3 days at 150,°C). Such performance, one of the highest obtained for a bilayer device fabricated by solution processing, is achieved as crosslinking does not disturb the ,,, stacking of the polymer as confirmed by GIWAXS measurements. These novel photocrosslinkable materials provide ready access to efficient bilayer devices thus enabling the fundamental study of photophysical characteristics, charge generation, and transport across a well-defined interface. [source] Endorsement advertising in aboriginal tourism: an experiment in TaiwanINTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 6 2005Janet Chang Abstract Aboriginal cultures have become important tourism attractions worldwide. Cultural villages provide ready access to selected aspects of these cultures in a staged format. They package and promote culture to tourists. Advertising is one component of the promotional mix. Using brochures as the advertising media, the objective of this research is to ascertain the types of advertising endorsers and advertising appeals that are most likely to be successful in attracting visitors to such cultural villages. Adopting an experimental approach, a two-factor experimental design is manipulated. The causal effect is obtained by using MANOVA and Scheffe tests. The findings are twofold: (1) the advertising effectiveness of using an aboriginal employee is better than using other types of endorsers; (2) an emotional advertising appeal elicits a better response than a rational advertising appeal. Copyright © 2005 John Wiley & Sons, Ltd. [source] Synthesis of acyclic nucleoside phosphonates as antiviral compoundsJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2000Frank Wormstädt Reaction of 6-chloropyrimidines with diethyl [(2-aminoethoxy)methyl]phosphonate allows for a ready access to acyclic nucleoside phosphonates. A series of 5-substituted pyrimidines bearing a phosphonate side chain at position 6 were synthesized and tested against herpes simplex viruses (HSV-1 and HSV-2) and human immunodeficiency virus (HIV-1). Some compounds showed weak antiviral activity against HSV-1. [source] Antibiotic prescribing rates for acute otitis media in a paediatric emergency departmentJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 4 2006Kai Steinmann Objective: To audit antibiotic prescribing rates for acute otitis media (AOM) at a tertiary paediatric emergency department (ED). Methods: All children who presented to the ED in 2002 (during defined 4-week periods in spring, summer, autumn and winter) and were given a diagnosis of AOM were eligible for analysis. Data were extracted retrospectively, providing information on demographics and antibiotic therapy. Results: A total of 306 patients with AOM were available for analysis. Forty-three children (14%) were <1 year, 69 (23%) 1,2 years, and 194 (63%) > 2 years of age. Sixty-eight patients (22%) were receiving antibiotics prior to presentation to the ED, and antibiotics were prescribed for 206 (67%). Antibiotic prescribing was independent of patient age. Conclusions: Despite ready access to clinical guidelines that recommend an expectant approach for children with AOM who are older than 1 or 2 years of age, antibiotic prescribing rates were high in the ED. [source] headspace: National Youth Mental Health Foundation: Making headway with rural young people and their mental healthAUSTRALIAN JOURNAL OF RURAL HEALTH, Issue 2 2007Craig A. Hodges Abstract Mental health is the number one health issue affecting young people in Australia today, yet only one in four of these young people receive professional help. Approximately 14% of 12- to 17-year-olds and 27% of 18- to 25-year-olds experience mental health problems each year. However, many do not have ready access to treatment or are reluctant to seek that help. These issues might be exacerbated in the rural and remote regions of Australia where sociocultural barriers such as stigma, lack of anonymity and logistic difficulties including cost and availability of transport can hinder young people accessing mental health services. headspace: the National Youth Mental Health Foundation has been funded to address these issues. headspace will provide funding for the establishment of communities of youth services across Australia, provide national and local community awareness campaigns and plans, establish a centre of excellence that will identify and disseminate evidence-based practice in addressing youth mental health issues, and translate findings into education and training programs that are targeted at service providers to work with youth mental health. The communities of youth services will build the capacity of local communities to identify early, and provide effective responses to, young people aged 12,25 years with mental health and related substance use disorders. Specific approaches in rural, regional and remote areas will be developed as well as specific programs to involve young Indigenous people. [source] Continuing professional development for veterinariansAUSTRALIAN VETERINARY JOURNAL, Issue 4 2005IW CAPLE Continuing professional development for veterinarians is expected to commence in the year after graduation and continue until retirement. The World Organisation for Animal Health standard for veterinary services is based on principles of an ethical, organisational and technical nature, and a mix of regulation, self-regulation and quality assurance approaches are used. Few jurisdictions have made a minimum requirement of continuing professional development, measured in hours or units, mandatory in 2004, however, there is an increasing expectation of veterinarians to keep a personal record of their continuing professional development activities. Such records might assist in defending complaints about professional misconduct, and provide a basis for planning and monitoring personal professional growth. Continuing professional development can be obtained by a variety of means through structured and unstructured learning activities. The rapid advances in communication technologies and ready access to available electronic databases at the beginning of the 21st century is rapidly changing the way students learn in veterinary schools and how they will acquire continuing professional development during their careers. Universities, governments, professional associations and special interest groups all have roles to play in the delivery of continuing professional development to the veterinary profession and to ensure a structure is in place to monitor improvements in the delivery of quality veterinary services. [source] The Galton,Darwin,Wedgwood Pedigree of H. H. LaughlinBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2010TIM M. BERRA fls A pedigree of the Galton,Darwin,Wedgwood families that was exhibited as a poster at the Third International Congress of Eugenics in 1932 at the American Museum of Natural History has been located in the archives of Truman State University in Kirksville, Missouri. This pedigree was prepared by Harry Hamilton Laughlin, Director of the Eugenics Record Office of the Carnegie Institute. The pedigree shows consanguineous marriages within the three families. A special collection of rare Darwin family photographs assembled by Leonard Darwin has also been found in the Truman State University archives. These photographs were exhibited as a poster alongside the pedigree at the 1932 Eugenics Congress. The poster of the Galton,Darwin,Wedgwood pedigree is published here, together with a tabular version providing ready access to the information contained in the pedigree. Also included are the Darwin family photographs and a biographical sketch of Laughlin. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101, 228,241. [source] The molecular genetics of the genodermatoses: progress to date and future directionsBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2003A.D. Irvine Summary The Human Genome Mapping Project and allied rapid advances in genetic technology over the past decade have facilitated accurate association of allelic variations in several genes with specific skin phenotypes. Currently the genetic bases of the majority of the more common genodermatoses have been elucidated. In scientific terms this work has been extraordinarily successful and has yielded many new biological insights. These advances, although exciting, have yet to be translated into direct benefit for patients with these diseases. Genetic counselling has been greatly aided by gene identification, by the better understanding of genotype,phenotype correlation and by the disclosure of unexpected genetic mechanisms in some families. Knowledge of the molecular basis of these disorders has also been vital in enabling DNA-based prenatal diagnosis in several conditions and DNA-based preimplantation diagnosis has been used in a selected few. While this successful period of gene mapping is now nearing completion, progress towards the next goal, that of developing therapeutic strategies based on the knowledge of these underlying genetic mechanisms, has proven frustratingly slow. Despite the ready access to the skin compared with solid internal organs, the challenges of cutaneous gene therapy are legion and many technical issues need to be surmounted to enable gene replacement or modification of gene expression to have a useful role in these disorders. In this article we make a comprehensive review of progress to date in gene identification, genotype,phenotype correlation, prenatal diagnosis and cutaneous gene therapy, and we examine future directions for research in this field. [source] | |||||||||||||