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Brief Historical Review (brief + historical_review)
Selected AbstractsExpanding field of purinergic signalingDRUG DEVELOPMENT RESEARCH, Issue 1-2 2001Geoffrey Burnstock Abstract This article attempts to paint a broad picture of the extraordinary explosive recent developments in the purinergic signaling field. After a brief historical review and update of purinoceptor subtypes, the focus is on the physiological roles of purines and pyrimidines. These are considered both in terms of short-term signaling in neurotransmission, secretion, and vasodilatation and in long-term (trophic) signaling in development, regeneration, proliferation, and cell death. Examples of trophic signaling include cartilage development in limb buds, glial cell proliferation, development of skeletal muscle, changes in receptor expression in smooth-muscle phenotypes, maturation of testicular spermatids, and bone remodeling. Plasticity of purinoceptor expression in pathological conditions is described, including the increase in the purinergic component of parasympathetic nervous control of the human bladder in interstitial cystitis and outflow obstruction and in sympathetic cotransmitter control of blood vessels in hypertensive rats, the appearance of P2X7 receptors in the glomeruli of the kidney from diabetic and transgenic hypertensive animal models, and up-regulation of P2X1 and P2Y2 receptor mRNA in hearts of rats with congestive heart failure. The role of P2X3 receptors in nociception is considered, and a new hypothesis about purinergic mechanosensory transduction in the gut is explored. A personal view of some of the areas ripe for future development concludes this article, including a discussion of different strategies that could lead to the development of purinergic therapeutic agents. Drug Dev. Res. 52:1,10, 2001. © 2001 Wiley-Liss, Inc. [source] The Development of the Observational MethodGEOMECHANICS AND TUNNELLING, Issue 5 2008Wulf Schubert o.Univ.-Prof. A continuous observation during construction always has been an important element of geotechnical engineering for minimizing risks. The reasons are the uncertainties in the geological and geotechnical models, as well as the limited capability to sufficiently accurately describe the complex ground behaviour. In the early days design of geotechnical structures thus was mainly based on experience. As usual, experience was used to develop mathematical solutions to the problem. To account for the inherent scatter of parameters and uncertainties in the models, the assumptions made during design had and have to be verified or falsified during construction by observations. For safe and economical construction, the design has to be adjusted during construction to the actual conditions. The term "observational method" was first formally introduced by Peck and Terzaghi. The original ideas behind the method have not always been understood or followed. After a brief historical review of the observational method the current status of the method is critically reviewed, and further developments discussed. Die Beobachtungsmethode einst und jetzt Die Schwierigkeit, den Baugrund ausreichend zu erkunden und dessen Interaktion mit dem Bauwerk zutreffend mathematisch zu modellieren, erfordert die laufende Beobachtung während des Baus, um die Baumaßnahmen an die tatsächlichen Verhältnisse anzupassen und das Risiko vermindern zu können. Mit vermehrter Erfahrung wurden auch Analysemodelle entwickelt. Zur Berücksichtigung der unvermeidlichen Streuung der Baugrundeigenschaften und der Unsicherheiten in den Modellen wurden und werden während des Baus Beobachtungen durchgeführt. Die Bezeichnung "Beobachtungsmethode" wurde formal von Peck und Terzaghi eingeführt. Die damals formulierten Grundsätze wurden nicht immer verstanden und befolgt. Im Beitrag wird nach einem kurzen historischen Rückblick über Entstehung und Entwicklung der Methode der derzeitige Stand kritisch beleuchtet, und weitere Entwicklungen werden diskutiert. [source] Making subjective judgments in quantitative studies: The importance of using effect sizes and confidence intervalsHUMAN RESOURCE DEVELOPMENT QUARTERLY, Issue 2 2006Jamie L. Callahan At least twenty-three journals in the social sciences purportedly require authors to report effect sizes and, to a much lesser extent, confidence intervals; yet these requirements are rarely clear in the information for contributors. This article reviews some of the literature criticizing the exclusive use of null hypothesis significance testing (NHST) and briefly highlights the state of NHST reporting in social science journals, including Human Resource Development Quarterly. Included are an overview of effect sizes and confidence intervals,their definitions, a brief historical review, and an argument regarding their importance. The article concludes with recommendations for changing the culture of quantitative research within human resource development (HRD) to more systematically reporting effect sizes and confidence intervals as supplements to NHST findings. [source] Current Concerns in Validity TheoryJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 4 2001Michael T. Kane We are at the end of the first century of work on models of educational and psychological measurement and into a new millennium. This certainly seems like an appropriate time for looking backward and looking forward in assessment. Furthermore, a new edition of the Standards for Educational and Psychological Testing (AERA, APA, & NCME, 1999) has been published, and the previous editions of the Standards have served as benchmarks in the development of measurement theory. This backward glance will be just that, a glance. After a brief historical review focusing mainly on construct validity, the current state of validity theory will be summarized, with an emphasis on the role of arguments in validation. Then how an argument-based approach might be applied will be examined in regards to two issues in validity theory: the distinction between performance-based and theory-based interpretations, and the role of consequences in validation. [source] Physical activity in cancer survivors: a field in motionPSYCHO-ONCOLOGY, Issue 4 2009Kerry S. Courneya Abstract Physical activity (PA) is an important health behavior in almost any population but it may be particularly helpful for cancer survivors. Objective: To introduce this special issue on PA in cancer survivors and to provide a summary of its important contributions to the field. Methods: A brief historical review of PA research in cancer survivors followed by a narrative review of the articles published in this special issue. Results: This special issue contains 13 original articles reporting 15 studies on PA in cancer survivors. Just over half of the studies focus on breast cancer survivors, whereas the remainder focus on understudied cancer survivor groups such as lung, ovarian, colorectal, prostate, hematologic, and pediatric. Moreover, a majority of the studies focus on the survivorship phase of the cancer continuum. Perhaps the most distinctive feature of this special issue is the number of studies focusing on the determinants of PA. Taken together, the 13 articles make significant contributions in four areas: (1) randomized controlled trials of PA interventions with supportive care endpoints, (2) observational studies on the determinants of PA, (3) observational studies on the ,determinants of PA determinants', and (4) studies on methodological and feasibility issues related to conducting PA trials. Conclusions: PA research is making an important contribution to the health and well-being of cancer survivors across the entire cancer control continuum. This special issue builds on this momentum and provides the single largest collective contribution of knowledge to date in the field of PA in cancer survivors. Copyright © 2009 John Wiley & Sons, Ltd. [source] Gene,environment interplay and psychopathology: multiple varieties but real effectsTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 3-4 2006Michael Rutter Gene,environment interplay is a general term that covers several divergent concepts with different meanings and different implications. In this review, we evaluate research evidence on four varieties of gene,environment interplay. First, we consider epigenetic mechanisms by which environmental influences alter the effects of genes. Second, we focus on variations in heritability according to environmental circumstances. Third, we discuss what is known about gene,environment correlations. Finally, we assess concepts and findings on the interaction between specific identified genes and specific measured environmental risks. In order to provide an understanding of what may be involved in gene,environment interplay, we begin our presentation with a brief historical review of prevailing views about the role of genetic and environmental factors in the causation of mental disorders, and we provide a simplified account of some of the key features of how genes ,work'. [source] Combination theory and equilibrium evaporationTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 574 2001M. R. Raupach Abstract This paper is an analysis of equilibrium evaporation and its role in the energy balance of a terrestrial surface, as described by combination theory. Three themes are covered: first, a brief historical review identifies multiple definitions of the concept of equilibrium evaporation. Second, these are formalized by developing the basic principles of combination theory with minimum approximation. Several measures are utilized to do this: linearization is avoided, radiative and storage coupling are incorporated systematically, and actual and linearized saturation deficits are distinguished. The formalism is used to analyse several algebraically defined states and limits for the surface energy balance. Third, the thermodynamic foundation of equilibrium evaporation is analysed by studying surface-atmosphere feedbacks in arbitrary closed and open evaporating systems. It is shown that under steady energy supply any closed evaporating system evolves towards a quasi-steady state in which the Bowen ratio takes the equilibrium value 1/,v, where ,v is the ratio of the latent- and sensible-heat contents of saturated air with temperature, evaluated at the volume-averaged temperature in the closed system. This applies whether the system is well-mixed or imperfectly mixed, and whatever the internal distribution of surface fluxes and surface and aerodynamic resistances. In contrast, open systems cannot reach such an equilibrium. This evolutionary definition of equilibrium evaporation differs from an alternative algebraic definition, the fully decoupled limit. The differences between the two definitions are identified, and the evolutionary definition is shown to be more fundamental. Thus, the correct temperature for evaluating , in determining equilibrium evaporation is the volume-averaged temperature in a closed region, which in the case of a convective boundary layer is well approximated by the mixed-layer temperature. [source] A retrospective view on research in neuroscience in NorwayACTA NEUROLOGICA SCANDINAVICA, Issue 2008L. Gjerstad This brief historical review on neuroscience in Norway shows a comparatively high research activity with many important results. The Norwegian zoologist Fridtjof Nansen, who later became a famous Arctic explorer, was the first to formulate the neuron doctrine. ,The Oslo School of Neuroanatomy' contributed enormously to the understanding of the detailed anatomy and chemistry of the central nervous system. Norwegian neurophysiologists made important findings from studies of hippocampus including the inhibitory basket cell, the LTP phenomenon and the ,hippocampal-slice-technique'. In clinical neuroscience the description of Refsum's disease and studies of myasthenia gravis and multiple sclerosis have been of particular importance. Two of 13 centres of excellence in Norway selected in 2003 were from neuroscience, and The Norwegian Research Council has its own programme for neuroscience. The Norwegian Neurological Association arranges annual meetings to promote interest in neurological research. [source] |