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Particular Significance (particular + significance)
Selected AbstractsFourier Transformed Large Amplitude Square-Wave Voltammetry as an Alternative to Impedance Spectroscopy: Evaluation of Resistance, Capacitance and Electrode Kinetic Effects via an Heuristic ApproachELECTROANALYSIS, Issue 15-16 2005Abstract A detailed simulation of Fourier transformed large amplitude square-wave voltammetry is presented in the frequency domain for the process Red,Ox+e,. The simulation takes into account the influence of the electrode kinetics (Butler,Volmer model), uncompensated resistance (Ru) and double layer capacitance (Cdl). Of particular significance is the prediction that the even harmonic responses are only detected in the presence of quasi-reversibility or uncompensated resistance, and also are essentially devoid of charging current. In contrast, the DC and odd harmonic AC components exhibit much larger faradaic currents and also contain charging current. Conveniently, detailed analysis of the simulated DC and AC harmonic components reveals the presence of readily recognised patterns of behaviour with unique levels of sensitivity to electrode kinetics, Ru and Cdl, that facilitate quantitative analysis of these terms. These electrochemical parameters are generally calculated by small amplitude impedance spectroscopy and utilisation of linear analysis of equivalent circuits. Experimental studies on the one electron oxidation of ferrocene in dichloromethane (0.1,M Bu4NPF6) and the one electron reduction of [Fe(CN)6]3, in aqueous 0.5,M KCl electrolyte analysed via heuristic forms of data analysis based on recognition of patterns of behaviour, are presented as examples of a reversible process with significant uncompensated resistance and a quasi-reversible process with minimal ohmic drop, respectively. Results demonstrate the advantages of a more intuitively implemented form of data analysis than presently available with conventional forms of impedance spectroscopy. [source] Environmental and economic development issues in the Polish motorway programme: a review and an analysis of the public debateENVIRONMENTAL POLICY AND GOVERNANCE, Issue 2 2002E. J. Judge This paper examines the development of the Polish motorway programme, though the lessons apply generally throughout the central and east European (CEE) region. This has particular significance for European transport policy as three major corridors of the Polish motorway network also form crucial links of the Trans European Network (TEN). Thus, until recently, motorways have been presented on the one hand (by the Polish government and its supporters) as a boost to national and regional development, and on the other (by its detractors, principally the environmental lobby) as a threat that will suck development out of the country, while saddling it with substantial environmental costs. Environmental pressure groups have sought to refute economic development arguments using Western research, and have seen such research as influential in public debate and decision making. Based on evidence drawn from official reports and documents and a content analysis of the public debate on motorway development using the media archive of the Polish Motorways Agency, this paper suggests that these arguments have so far in fact been overshadowed by environmental considerations, and even more by financing issues. However, the future direction of policy is uncertain because of political changes after the September 2001 election. Copyright © 2002 John Wiley & Sons, Ltd and ERP Environment. [source] Coordination complexes of functionalized pyrazines with metal ions: reagents for the controlled release of flavourant molecules at elevated temperaturesFLAVOUR AND FRAGRANCE JOURNAL, Issue 2 2006Colin Baillie Abstract The potential for stabilization of volatile flavourant molecules such as functionalized pyrazines by coordination to metal ions, and the application of the resultant coordination complexes as controlled release agents at elevated temperatures were explored. New complexes containing the flavourant molecules 2,3,5-trimethylpyrazine (TMP), 2-ethyl-3-methylpyrazine (EMP) and 2-acetylpyrazine (ACP) with copper(II) and copper(I) salts were prepared and structurally characterized. Representative examples of known copper(II) and calcium(II) complexes containing pyrazine carboxylic acids were also prepared. The complexes were examined by thermal analysis techniques and demonstrated, by a combination of thermogravimetric (TGA) and pyrolysis GC,MS analyses, to act as convenient reagents for the release of the parent pyrazine at elevated temperatures. Thus, pyrolysis GC,MS revealed that the complex [Cu3Cl3(EMP)2]n cleanly releases EMP in 96.5% selectivity at 200 °C. Of particular significance is that the calcium complex [Ca(3-aminopyrazine-2-carboxylate)2·H2O], under ramped pyrolysis conditions, was shown to undergo decarboxylation prior to the release of 2-aminopyrazine (AMP), as essentially the only volatile component, in the temperature range 600,800 °C. This finding provides a precedent for the application of complexes of pyrazinecarboxylate salts with metal ions (of which an almost infinite number of combinations is potentially available) as controlled release agents of the parent pyrazine molecule at elevated temperatures, suitable for exploitation by the foodstuffs, flavour and fragrance industries. Copyright © 2006 John Wiley & Sons, Ltd. [source] Professional socialization: The key to survival as a newly qualified nurseINTERNATIONAL JOURNAL OF NURSING PRACTICE, Issue 2 2007Higher DiplomaArticle first published online: 29 MAR 200, MSc (Nursing), Mary Mooney RGN The impact and prevalence of professional socialization in nursing has been written about extensively. Despite the many positive developments that have taken place in nursing within the past decade, the role of professional socialization remains heavily weighted and is of particular significance to those nurses who are newly qualified. The account given by newly registered nurses in this study demonstrates that their ability and willingness to become professionally socialized determines their ease of survival at clinical level. Twelve newly qualified Irish nurses, from two separate cohorts, were interviewed to ascertain their perceptions of becoming newly qualified nurses. A grounded theory approach was used and data were analysed using thematic analysis. A category that emerged was linked very strongly with professional socialization. The respondents did not refer to professional socialization per se, but through the coding process this emerged as the linchpin of the discussion. [source] Resonances and pseudoresonances in a potential with attractive coulomb tail: A study using analytic-continuation techniquesINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 2 2003Imke B. Müller Abstract The performance of the complex absorbing potential (CAP) and the complex scaling (CS) methods in the detection and calculation of complex Siegert energies is studied using a 1-D long-range attractive model potential. This potential is constructed to mimic molecular properties, in particular an attractive Coulombic term, to allow one to draw conclusions on molecular ab initio studies. Analyzing the spectrum of the model potential, one compact bound state embedded in the manifold of Rydberg states is found that shows artificial resonance characteristics when applying the CAP and the CS methods. This pseudoresonance problem is less pronounced in the calculation using the CS method than in that using the CAP method. Despite this deficiency, the CAP method is shown to possess advantages over CS when dealing with physical resonances under conditions that simulate the application of standard basis sets in ab initio calculations. The accuracy of the Siegert energy is shown to be maintained when applying a subspace projection technique to the CAP method. This technique reduces the computational demand significantly and leads to an important improvement of the CAP method, which should be of particular significance in molecular applications. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003 [source] Integration, Participation, Identity: Immigrant Associations in the Province of MilanINTERNATIONAL MIGRATION, Issue 2 2010Marco Caselli The paper presents some results from a multi-year research project on immigrant associations in the province of Milan, Italy. The analysis yields numerous issues for reflection and recurrent features of particular significance. The first is the fact that for all the associations surveyed, their main goal and the essential reason for their existence was the desire to integrate their community of membership into the host society. However, such integration did not consist in a desire to be assimilated into Italian society. Quite the opposite: the majority of the associations studied were wholly committed to maintaining -- and sometimes rediscovering -- the identity and culture of their reference community. The second main feature is that immigrant associations are crucial nodes in a dense network of relations involving numerous actors of very different kinds: the immigrants themselves, other immigrant associations, third-sector organizations, and the local authorities. The third and final important issue concerns the representativeness of immigrant associations: whether, that is, they can be considered the legitimate representatives of the community of membership. [source] Beyond polarities of knowledge: the pragmatics of faithNURSING PHILOSOPHY, Issue 1 2002Gweneth A. Hartrick RN Abstract The dissociation between the domains of knowledge continues to perpetuate the fragmentation of people's health and healing experiences. Of particular significance are the polarities that have been created between the objective, subjective and spiritual dimensions of knowledge and human experience. This paper offers a consideration of how faith might serve as a pragmatic avenue towards assuaging the polarities between knowledges and enhancing nurses' ability to attend to the complex and mulitdimensional nature of health and healing processes. [source] Lateral compaction effects in braided structuresPOLYMER COMPOSITES, Issue 2 2003Robert A. Dasilva This paper addresses the phenomenology of strand interaction in biaxial non-embedded braided textile structures under uniaxial tension. The specific interest in the development of new braided textile structures is a result of the shortcomings of current rope, belt, and cable performance under large strain controlled conditions. However, this work also holds particular significance in the area of textile composite preforms. In composites forming, the lateral strand compaction mechanism, which drives braid behavior under tension, may be applied to woven fabrics for predicting wrinkling during forming processes. Additionally, manufacturing models produced in this study may be used to predict shape and size limitations of braided composite preforms. In this paper, a generalized model is developed for these structures with the intent of characterizing and predicting mechanical behavior. The methodology consists of a modular framework, which includes the prediction of manufacturing parameters. Lateral strand compaction tests were performed to generate constitutive material curves for use in analytical geometric models. Model predictions correlate well with data generated from braid uniaxial tension tests. Results suggest that lateral strand strain drives braid tensile behavior. [source] Practitioner Review: Bridging the gap between research and clinical practice in pediatric obesityTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 2 2007Elissa Jelalian Background:, Pediatric obesity is a significant public health concern, with rising prevalence rates in both developed and developing countries. This is of particular significance given that overweight children and adolescents are at increased risk for multiple medical comorbidities, as well as psychosocial and behavioral difficulties. The current review highlights findings from the empirical pediatric obesity treatment literature, with particular attention to diet, physical activity, and behavior interventions. Evaluation and treatment considerations relevant to working with overweight children and adolescents with psychiatric comorbidities are reviewed. Methods:, Review of the relevant treatment literature, with a focus on randomized clinical trials, was conducted. Recommendations regarding treatment of children and adolescents with psychiatric comorbidities are based on relevant prospective studies of the relationship between weight status and psychological variables and studies with adult populations. Results:, Well-established pediatric weight control interventions have been conducted in research settings. These studies provide a starting point, but are limited by homogeneous samples that may exclude participants with psychiatric comorbidities. Practitioners treating obese children and adolescents with psychiatric disorders are encouraged to assess individual, familial, and contextual variables specific to weight (e.g., motivation and existing support to change current eating and physical activity patterns, extent of weight-related conflict within family, impact of weight on current functioning) in order to prioritize treatment objectives. Conclusions:, The review concludes with a discussion of current empirical and practical challenges, including explicitly targeting obese children and adolescents with psychiatric concerns and determining appropriateness of pursuing weight control interventions in this population. [source] Trance and Shamanic Cure on the South American Continent: Psychopharmacological and Neurobiological InterpretationsANTHROPOLOGY OF CONSCIOUSNESS, Issue 1 2010FRANCOIS BLANC ABSTRACT This article examines the neurobiological basis of the healing power attributed to shamanic practices in the Andes and Brazil in light of the pharmacology of neurotransmitters and the new technological explorations of brain functioning. The psychotropic plants used in shamanic psychiatric cures interfere selectively with the intrinsic neuromediators of the brain. Mainly they may alter: (1) the neuroendocrine functioning through the adrenergic system by controlling stressful conditions, (2) the dopaminergic system in incentive learning and emotions incorporation, (3) the serotoninergic system in modulating behaviors, and mood, and (4) basic functions implied in anxiety or depression. PET scans and functional magnetic resonance imaging studies of hypnotic trance and altered states of consciousness may provide a useful model for the neurophysiological phenomena of shamanic drum-and-dance trance. The reorganization of cortical areas and the direct interconnections between the prefrontal cortex and the dopaminergic reward centers in the limbic system are of particular significance for human social judgment and symbolic processing. Those centers,including the hypothalamus and the amygdala (associated with psychosomatic equilibrium, memory, and emotion) are enhanced. This arousal may be amplified in order to induce a cathartic crisis,the shamanic trance. It is suggested that through this holistic approach the shaman empirically interferes in neurobiological dysfunctions. [source] P2X7 receptors in rat parotid acinar cells: formation of large poresAUTONOMIC & AUTACOID PHARMACOLOGY, Issue 4 2001Simon J. Gibbons 1 Permeabilization of cells mediated by P2X7 receptors occurs to varied degrees in native and heterologous expression systems. Previous studies on P2X7 receptors in parotid acinar cells suggested that ATP does not permeabilize these cells. 2 Modification of the assay conditions showed that ATP permeabilizes freshly dissociated rat parotid acinar cells to the fluorescent dye YOPRO-1. 3 The pharmacological and physiological properties of this effect indicate that permeabilization is mediated by the P2X7 receptor. Adenosine 5,-triphosphate (ATP) and 3,- O -(4-benzoyl)benzoyl adenosine 5,-triphosphate (BzBzATP) were effective agonists with EC50 values of 49.3 and 0.6 ,M, respectively. 4 Permeabilization was best observed in low divalent cation concentrations and at physiological temperatures. Previous studies failed to detect permeabilization because of the sensitivity of this effect to temperature and divalent cations. 5 An important consideration in understanding the effect of divalent cations is that the fluorescence of YOPRO-1/nucleic acid complexes is directly quenched by addition of divalent cations. This must be considered if quantitative study of the interaction of divalent cations with P2X7 receptors is carried out using fluorescent DNA-binding dyes. 6 In summary, our data show that P2X7 receptors in parotid acinar cells can form large pores in the plasma membrane. This property likely contributes to signalling and may be cytotoxic and have particular significance in damaged or inflamed salivary glands. [source] New perspectives on Cooksonia from the Lower Devonian of the Welsh BorderlandBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2002K. S. HABGOOD New collections of coalified mesofossils of Cooksonia have been made from a Lochkovian (Lower Devonian) locality in Shropshire, England. They allow detailed description of sporangial anatomy in Cooksonia pertoni ssp. apiculispora with inferences for spore dispersal involving disintegration of the distal sporangial wall and maintenance of a rigid rim. Trilete spores, Aneurospora sp. and Streelispora newportensis have been recovered from the same sporangium. A new subspecies Cooksonia pertoni subsp reticulispora contains miospores with laevigate proximal surface bearing a simple triradiate apertural fold, equatorial crassitude and a coarse reticulum of muri on a slightly thickened distal wall. Spores are tentatively assigned to Synorisporites sp.. Cooksonia banksiisp. nov. is based on terminal sporangia in which the spore-containing area is enclosed within the expanded apex of the subtending axis. The cavity is lined by a smooth resilient acellular layer. Well-defined cells are apparent only in the pronounced sporangial rim. Spores are assigned to Ambitisporites avitus, a taxon of particular significance, because it is recorded in the Upper Ordovician and Lower Silurian assemblages which contain the earliest trilete monads. However, it is concluded that spores of such simple morphology may have been produced by a variety of taxa and that ultrastructural studies are necessary to confirm this possibility. These new specimens thus allow further insights into the disparity (via anatomy and in situ spores) of very simple plants and, in providing information on cell construction and arrangement, allow for functional interpretations, particularly relating to spore dispersal. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society, 2002, 139, 339,359. [source] Clinical Pharmacology: Principles and practice of drug therapy in medical educationBRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 1 2002Brian Whiting Educational reform has taken place in many Medical Schools. A traditional passive approach has been replaced by a more active, student-centred approach, founded on Problem-Based Learning. This has not been without risk because many well-structured courses have been abandoned, and this is of particular significance to the principles and practice of drug therapy. Here we outline an approach which could be incorporated into a medical curriculum and suggest some guidelines and a list of questions that should be asked in clinical situations involving drug therapy. [source] 2432: Histological characteristics of the posterior lid marginACTA OPHTHALMOLOGICA, Issue 2010N KNOP Purpose The structure of the lid margin is insufficiently understood and defined although it is of obvious importance for ocular surface integrity. In particular the histological structure of the tissues of the normal lid margin and their zonal differentiation is partly unclear. Methods The structure and function of the different zones at the posterior lid margin are explained with a focus on dry eye disease, based on the available literature on the lid margin together with own findings on the histology of normal and pathological tissues from the human lid margin. Results The Meibomian glands (MG) that are of particular significance for the integrity of the ocular surface open still within the cornified epidermis. Their obstructive dysfunction (MGD) is a main cause for dry eye disease. The orifice is followed by the mucocutaneous junction (MCJ) that extends from the abrupt termination of the epidermis to the crest of the inner lid border. The physiological vital stainable line of Marx represents its surface and can be used as a diagnostic tool for the location and functionality of the MG orifices and lacrimal puncta. The marginal conjunctiva starts at the crest of the inner lid border and forms a thickened epithelial cushion. This is the point in closest apposition to the globe, represents the zone that wipes the bulbar surface and distributes the thin pre-ocular tear film. It is hence termed as the lid wiper and pathological alterations that result in a vital staining are a sensitive early indicator of dry eye disease. Conclusion The margin of the eyelid is an important but yet underestimated structure for the maintenance of the pre-ocular tear film and of utmost importance for the preservation of ocular surface integrity and for development of dry eye disease. Support DFG KN317/11 [source] | |||||||||||||||||||||||||