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Selected Abstractsp -Phenylenediamine sensitization is more prevalent in central and southern European patch test centres than in Scandinavian: results from a multicentre studyCONTACT DERMATITIS, Issue 6 2009Jacob Pontoppidan Thyssen Background:, Positive patch test reactions to p -phenylenediamine (PPD) are common. PPD is used in oxidative hair dyes and is also present in dark henna temporary ,tattoos'. Cross-sensitization to other contact allergens may occur. Because subjects sensitized to PPD are at risk of clinically severe reactions upon hair dyeing, there is a need for ,current' prevalence data on PPD sensitization. Objectives:, To compare PPD patch test results from dermatitis patients tested between 2003 and 2007 in 10 European patch test centres and to analyse the causes and determine relevance of positive PPD patch test reactions. Materials:, Patch testing was performed using PPD (1% free base in petrolatum from Trolab (Almirall Hermal GmbH, Reinbeck, Germany) or Chemotechnique (Malmö, Sweden), equivalent to 0.090 mg/cm2 in the TRUE® test from MEKOS Laboratories AS). Statistical analysis was performed using the chi-squared test. Results:, The weighted average prevalence was 4.6% among 21 515 patients. PPD sensitization occurred more often in centres located in Central and Southern Europe than in Scandinavian centres (odds ratio = 2.40; 95% confidence interval = 2.07,2.78). The overall proportion of positive patch test reactions to PPD that were registered as being of either current or ,past' relevance was high (weighted average 53.6% and 20.3%, respectively). Consumer hair dyeing was the most prominent cause of PPD sensitization (weighted average 41.8%). Furthermore, occupational hair dye exposure (10.6%) and cross-sensitization to textile dyes (12.6%) were frequently reported. Conclusions:, PPD sensitization caused by exposure to hair dyes is frequent and remains a present problem for patients visiting contact dermatitis clinics, especially in patch test centres located in Central and Southern Europe. [source] Numerical simulation of high-temperature phase change heat storage systemHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 1 2004Yu-Ming Xing Abstract In this paper, numerical results pertaining to cyclic melting and freezing of an encapsulated phase-change material (PCM) have been reported. The cyclic nature of the present problem is relevant to latent heat thermal energy storage system used to power solar Brayton engines in space. In particular, a physical and numerical model of the single-tube phase change heat storage system was developed. A high-temperature eutectic mixture of LiF-CaF2 was used as the PCM and dry air was used as the working fluid. Numerical results were compared with available experimental data. The trends were in close agreement. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(1): 32,41, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10132 [source] Study of non-Fickian diffusion problems with the potential field in the cylindrical co-ordinate systemINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 5 2003Han-Taw Chen Abstract The present study applies a hybrid numerical scheme of the Laplace transform technique and the control volume method in conjunction with the hyperbolic shape functions to investigate the effect of a potential field on the one-dimensional non-Fickian diffusion problems in the cylindrical co-ordinate system. The Laplace transform method is used to remove the time-dependent terms in the governing differential equation and the boundary conditions, and then the resulting equations are discretized by the control volume scheme. The primary difficulty in dealing with the present problem is the suppression of numerical oscillations in the vicinity of sharp discontinuities. Results show that the present numerical results do not exhibit numerical oscillations and the potential field plays an important role in the present problem. The strength of the jump discontinuity can be reduced by increasing the value of the potential gradient. The propagation speed of mass wave is independent of the potential gradient and the boundary condition. Copyright © 2003 John Wiley & Sons, Ltd. [source] Longitudinal tooth fractures: findings that contribute to complex endodontic diagnosesENDODONTIC TOPICS, Issue 1 2007ERIC M. RIVERA The purpose of this review is to describe and discuss the diagnostic and treatment challenges related to tooth fractures primarily in the vertical plane, that is, the long axis of the crown and/or root. This includes when and how to identify and determine the extent of the fracture, when a coronal restoration should be placed, when root canal treatment is needed, and when a tooth or root should be extracted based on the location and extent of the fracture. The term ,longitudinal fractures' is used because they usually represent vertical extensions of fractures over distance and time. These fractures often present problems with diagnosis and treatment, but should be considered as findings only. They are not to be considered as pulpal or periapical diagnoses, but as pathways for bacteria that may induce pulpal and/or periapical inflammation or disease. Longitudinal fractures are divided into five definitive classifications, generally from least to most severe: (1) craze lines; (2) fractured cusp; (3) cracked tooth; (4) split tooth; and (5) vertical root fracture. These differ but have frequently been confused or combined in clinical articles, creating misunderstanding and resulting in incorrect diagnosis and inappropriate treatment. These classifications have been devised to provide global definitions that researchers and clinicians can use to eliminate this confusion. This review is subdivided into these five classifications as to incidence, pathogenesis, clinical features, etiologies, diagnosis, treatment, prognosis, and prevention. [source] THEORIZING GLOBAL BUSINESS SPACESGEOGRAFISKA ANNALER SERIES B: HUMAN GEOGRAPHY, Issue 3 2009Andrew Jones ABSTRACT. Over the last decade, geographers have paid a great deal of attention to transnational firms (TNCs) and global production networks (GPNs) in the global economy, to the emergence of a mobile transnational business class and also to the development of global or globalizing cities. All three literatures have made important contributions to understanding the spatiality of global economic activity, but each adopts a fairly discreet theoretical and empirical focus. This article aims to outline a number of theoretical dimensions for thinking about how these key strands to the globalization debate can be brought together through the concept of global business spaces. It will propose a framework for understanding the spatialities of global economic activity that seeks to capture the complex interaction of material, social, organizational and virtual spaces that form the context through which it is constituted. With reference to business travel as a key form of economic practice which plays a central role in (re)producing these spaces, it assesses how these emerging spaces of global economic activity present problems for the conceptual categories commonly used by both urban and economic geographers. In so doing, it proposes a series of ways in which a different research agenda can produce new insight into the complex forms of social practice at the centre of global economic activity. [source] Design and preparation of polyphenyl distance markers for solid-state 19F NMRISRAEL JOURNAL OF CHEMISTRY, Issue 3-4 2000Kenji Monde With 13C-labeled samples, it is possible to measure internuclear distances up to 7 Å by solid-state NMR, thus providing a powerful tool for probing ligand,receptor interactions. However, limitations in measurable distances and appreciable natural abundant 13C background signals present problems in solid-state 13C NMR. In order to overcome these disadvantages, a set of reference compounds with known F,F distances, namely, quinolinol, p -biphenyl, and p -terphenyl-bearing trifluoromethyl and trifluoromethylthio groups, have been synthesized. The preparation of these reference compounds and means for diluting these references in solid-state NMR are described. [source] Truth and validity in grounded theory , a reconsidered realist interpretation of the criteria: fit, work, relevance and modifiabilityNURSING PHILOSOPHY, Issue 3 2003Kirsten Lomborg RN BA MSN Abstract Grounded theory is a frequently used approach in nursing research. Over the years the methodology has developed in different directions with ambiguous answers to questions of truth and validity. This ambiguity influences the interpretation of the criteria for quality judgement of grounded theories: fit, work, relevance and modifiability. In particular, the criterion fit seems to be caught in a vacuum between different epistemological and ontological positions. Fit can be interpreted either from a realist or from a nonrealist position but both present problems. A realist position is problematic if it insists on an immutable empirical world and ignores the social and psychological aspects of human life. A nonrealist position can either be argued to rely on hidden realist assumptions and therefore to be inconsistent, or it can be relativistic, opening up the possibility of ,anything goes' attitudes in research and solipsistic confirmations of the world view of researchers with little or misleading practical impact. A reconsideration of the realist position is suggested, in which validity is regulated by the social constructed reality ,as it really is'. From this position fit is a matter of correspondence to facts in social reality. The criteria work, relevance and modifiability are argued to support the fitness of a theory, and to be useful in the broader evaluation of the quality of grounded theories. [source] The Wenlock Cyrtograptus species of the Builth Wells District, central WalesPALAEONTOLOGY, Issue 2 2004Mark Williams The Wenlock sequence of the Builth Wells district, central Wales is dominated by long-ranging Monograptus, Pristiograptus and Monoclimacis species. Cyrtograptus species, which underpin the graptolite biozonation, represent only about 10 per cent of recovered individuals. Ten Cyrtograptus species are present, most being zonal index species for the Builth district or other Wenlock sequences. Redescription of these Cyrtograptus species and comparison with all pertinent type material indicates that: the early Wenlock Cyrtograptus insectus, C. centrifugus and C. murchisoni are best distinguished by means of first whorl diameter, sicula length and differences of cladial development; mid Wenlock Cyrtograptus rigidus may bear a secondary cladium, but at Builth there are no stratigraphically discrete subspecies; Cyrtograptus linnarssoni is known only from its type locality; the long, gracile proximal part of the rhabdosome of C. ellesae facilitates its distinction from C. perneri, with which it has been confused, and indicates similarities to C. ramosus and C. lundgreni. Differences in the ranges of key Cyrtograptus species present problems for correlation between the lundgreni Biozone of the Builth district and the perneri-ramosus and lundgreni biozones of central Europe. The low diversity and abundance of the cyrtograptid fauna of the Builth district, compared to those of Arctic Canada and the Czech Republic, suggests relatively inhospitable conditions for graptolites. [source] Taxes, Time, and Support for SecurityPUBLIC BUDGETING AND FINANCE, Issue 2 2008AMY K. DONAHUE New technologies have been developed in response to terrorism. These present problems for local officials: implementing technologies will be expensive, and no technologies exist that can be used to gauge demand. We apply contingent valuation methodologies to determine support for additional taxes to pay for new terrorism-related technologies and services. We present findings from a national survey about people's attitudes toward terrorism prevention and response. We find that respondents generally support new services and technologies and local tax increases to pay for them. We also find that respondents are willing to pay more if programs have everyday uses that would enhance public safety, but are less supportive as inconveniences increase. [source] Lessons learned from the clinical reappraisal study of the Composite International Diagnostic Interview with LatinosINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 2 2009Margarita Alegria Abstract Given recent adaptations of the World Health Organization's World Mental Health Composite International Diagnostic Interview (WMH-CIDI), new methodological studies are needed to evaluate the concordance of CIDI diagnoses with clinical diagnostic interviews. This paper summarizes lessons learned from a clinical reappraisal study done with US Latinos. We compare CIDI diagnoses with independent clinical diagnosis using the World Mental Health Structured Clinical Interview for DSM-IV (WMH-SCID 2000). Three sub-samples stratified by diagnostic status (CIDI positive, CIDI negative, or CIDI sub-threshold for a disorder) based on nine disorders were randomly selected for a telephone re-interview using the SCID. We calculated sensitivity, specificity, and weight-adjusted Cohen's kappa. Weighted 12 month prevalence estimates of the SCID are slightly higher than those of the CIDI for generalized anxiety disorder, alcohol abuse/dependence, and drug abuse/dependence. For Latinos, CIDI-SCID concordance at the aggregate disorder level is comparable, albeit lower, to other published reports. The CIDI does very well identifying negative cases and classifying disorders at the aggregate level. Good concordance was also found for major depressive episode and panic disorder. Yet, our data suggests that the CIDI presents problems for assessing post-traumatic stress disorder (PTSD) and generalized anxiety disorder (GAD). Recommendations on how to improve future versions of the CIDI for Latinos are offered. Copyright © 2009 John Wiley & Sons, Ltd. [source] A review of the terms agglomerate and aggregate with a recommendation for nomenclature used in powder and particle characterizationJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 10 2002Gary Nichols Abstract The terms "agglomerate" and "aggregate" are widely used by powder technologists to describe assemblages of particles that are found in dry powders and powders in liquid suspensions. Each term has a specific meaning but, unfortunately, they are frequently interchanged at will and this has resulted in universal confusion. This confusion is perpetuated by conflicting definitions in national and international standards and this presents problems when describing powder properties or communicating results in reports and research papers. This paper reviews the current status of the definitions, with particular emphasis on their use in the pharmaceutical industry. It is proposed that just one term, agglomerate, should be used to describe an assemblage of particles in a powder and that the term aggregate should be confined to pre-nucleation structures. © 2002 Wiley-Liss Inc. and the American Pharmaceutical Association J Pharm Sci 91:2103,2109, 2002 [source] Assessment of functional vision and its rehabilitationACTA OPHTHALMOLOGICA, Issue 2 2010August Colenbrander Abstract. This article, based on a report prepared for the International Council of Ophthalmology (ICO) and the International Society for Low Vision Research and Rehabilitation (ISLRR), explores the assessment of various aspects of visual functioning as needed to document the outcomes of vision rehabilitation. Documenting patient abilities and functional vision (how the person functions) is distinct from the measurement of visual functions (how the eye functions) and also from the assessment of quality of life. All three areas are important, but their assessment should not be mixed. Observation of task performance offers the most objective measure of functional vision, but it is time-consuming and not feasible for many tasks. Where possible, timing and error rates provide an easy score. Patient response questionnaires provide an alternative. They may save time and can cover a wider area, but the responses are subjective and proper scoring presents problems. Simple Likert scoring still predominates but Rasch analysis, needed to provide better result scales, is gaining ground. Selection of questions is another problem. If the range of difficulties does not match the range of patient abilities, and if the difficulties are not distributed evenly, the results are not optimal. This may be an argument to use different outcome questions for different conditions. Generic questionnaires are appropriate for the assessment of generic quality of life, but not for specific rehabilitation outcomes. Different questionnaires are also needed for screening, intake and outcomes. Intake questions must be relevant to actual needs to allow prioritization of rehabilitation goals; the activity inventory presents a prototype. Outcome questions should be targeted at predefined rehabilitation goals. The Appendix cites some promising examples. The Low Vision Intervention Trial (LOVIT) is an example of a properly designed randomized control study, and has demonstrated the remarkable effectiveness of vision rehabilitation. It is hoped that further similar studies will follow. [source] | ||||||||||||||||