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Kinds versus continua: a review of psychometric approaches to uncover the structure of psychiatric constructs
- D. Borsboom, M. Rhemtulla, A. O. J. Cramer, H. L. J. van der Maas, M. Scheffer, C. V. Dolan
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- Journal:
- Psychological Medicine / Volume 46 / Issue 8 / June 2016
- Published online by Cambridge University Press:
- 21 March 2016, pp. 1567-1579
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The question of whether psychopathology constructs are discrete kinds or continuous dimensions represents an important issue in clinical psychology and psychiatry. The present paper reviews psychometric modelling approaches that can be used to investigate this question through the application of statistical models. The relation between constructs and indicator variables in models with categorical and continuous latent variables is discussed, as are techniques specifically designed to address the distinction between latent categories as opposed to continua (taxometrics). In addition, we examine latent variable models that allow latent structures to have both continuous and categorical characteristics, such as factor mixture models and grade-of-membership models. Finally, we discuss recent alternative approaches based on network analysis and dynamical systems theory, which entail that the structure of constructs may be continuous for some individuals but categorical for others. Our evaluation of the psychometric literature shows that the kinds–continua distinction is considerably more subtle than is often presupposed in research; in particular, the hypotheses of kinds and continua are not mutually exclusive or exhaustive. We discuss opportunities to go beyond current research on the issue by using dynamical systems models, intra-individual time series and experimental manipulations.
Endothelial dysfunction is associated with a greater depressive symptom score in a general elderly population: the Hoorn Study
- T. T. van Sloten, M. T. Schram, M. C. Adriaanse, J. M. Dekker, G. Nijpels, T. Teerlink, P. G. Scheffer, F. Pouwer, C. G. Schalkwijk, C. D. A. Stehouwer, R. M. A. Henry
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- Journal:
- Psychological Medicine / Volume 44 / Issue 7 / May 2014
- Published online by Cambridge University Press:
- 13 August 2013, pp. 1403-1416
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Background
Endothelial dysfunction (ED), low-grade inflammation (LGI) and oxidative stress (OxS) may be involved in the pathobiology of depression. Previous studies on the association of these processes in depression have yielded contradictory results. We therefore investigated comprehensively, in a population-based cohort study, the association between ED, LGI and OxS on the one hand and depressive symptoms on the other.
MethodWe used data from the Hoorn Study and determined biomarkers of ED [flow-mediated dilatation (FMD), von Willebrand factor, soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1, soluble thrombomodulin and soluble endothelial selectin], LGI [C-reactive protein, tumour necrosis factor-α, interleukin 6, interleukin 8, serum amyloid A, myeloperoxidase (MPO) and sICAM-1] and OxS (oxidized low density lipoprotein and MPO). Depressive symptoms were quantified by the Center for Epidemiologic Studies Depression Scale (CES-D) questionnaire (n = 493; age 68 years; 49.9% female). Regression analyses were performed with the use of biomarker Z scores. Adjustments were made for age, sex and glucose metabolism status (cohort stratification variables) and prior cardiovascular disease, hypertension, waist-to-hip ratio, cholesterol levels, education level, physical activity, dietary habits, and the use of antihypertensive and/or lipid-lowering medication and/or metformin (potential confounders).
ResultsAfter adjustment for age, sex and glucose metabolism status, one standard deviation increase in the ED Z score was associated with a 1.9 [95% confidence interval (CI) 0.7–3.1] higher CES-D score. Additional adjustments did not materially change this result. LGI and OxS were not associated with the CES-D score.
ConclusionsED, as quantified by an array of circulating biomarkers and FMD, was independently associated with depressive symptoms. This study supports the hypothesis that ED plays an important role in the pathobiology of depression.
A Marine Reservoir Correction for the Houtman-Abrolhos Archipelago, East Indian Ocean, Western Australia
- Peter Squire, Renaud Joannes-Boyau, Anja M Scheffers, Luke D Nothdurft, Quan Hua, Lindsay B Collins, Sander R Scheffers, Jian-xin Zhao
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- Journal:
- Radiocarbon / Volume 55 / Issue 1 / 2013
- Published online by Cambridge University Press:
- 19 January 2016, pp. 103-114
- Print publication:
- 2013
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High-precision analysis using accelerator mass spectrometry (AMS) was performed upon known-age Holocene and modern, pre-bomb coral samples to generate a marine reservoir age correction value (ΔR) for the Houtman-Abrolhos Archipelago (28.7°S, 113.8°E) off the Western Australian coast. The mean ΔR value calculated for the Abrolhos Islands, 54 ± 30 yr (1 σ) agrees well with regional ΔR values for Leeuwin Current source waters (N-NW Australia-Java) of 60 ± 38 yr. The Abrolhos Islands show little variation with ΔR values of the northwestern and north Australian coast, underlining the dominance of the more equilibrated western Pacific-derived waters of the Leeuwin Current over local upwelling. The Abrolhos Islands ΔR values have remained stable over the last 2896 cal yr BP, being also attributed to the Leeuwin Current and the El Niño Southern Oscillation (ENSO) signal during this period. Expected future trends will be a strengthening of the teleconnection of the Abrolhos Islands to the climatic patterns of the equatorial Pacific via enhanced ENSO and global warming activity strengthening the Leeuwin Current. The possible effect upon the trend of future ΔR values may be to maintain similar values and an increase in stability. However, warming trends of global climate change may cause increasing dissimilarity of ΔR values due to the effects of increasing heat stress upon lower-latitude coral communities.
Contributors
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- By Jane E. Adcock, Yahya Aghakhani, A. Anand, Eva Andermann, Frederick Andermann, Alexis Arzimanoglou, Sandrine Aubert, Nadia Bahi-Buisson, Carman Barba, Agatino Battaglia, Geneviève Bernard, Nadir E. Bharucha, Laurence A. Bindoff, William Bingaman, Francesca Bisulli, Thomas P. Bleck, Stewart G. Boyd, Andreas Brunklaus, Harry Bulstrode, Jorge G. Burneo, Laura Canafoglia, Laura Cantonetti, Roberto H. Caraballo, Fernando Cendes, Kevin E. Chapman, Patrick Chauvel, Richard F. M. Chin, H. T. Chong, Fahmida A. Chowdhury, Catherine J. Chu-Shore, Rolando Cimaz, Andrew J. Cole, Bernard Dan, Geoffrey Dean, Alessio De Ciantis, Fernando De Paolis, Rolando F. Del Maestro, Irissa M. Devine, Carlo Di Bonaventura, Concezio Di Rocco, Henry B. Dinsdale, Maria Alice Donati, François Dubeau, Michael Duchowny, Olivier Dulac, Monika Eisermann, Brent Elliott, Bernt A. Engelsen, Kevin Farrell, Natalio Fejerman, Rosalie E. Ferner, Silvana Franceschetti, Robert Friedlander, Antonio Gambardella, Hector H. Garcia, Serena Gasperini, Lorenzo Genitori, Gioia Gioi, Flavio Giordano, Leif Gjerstad, Daniel G. Glaze, Howard P. Goodkin, Sidney M. Gospe, Andrea Grassi, William P. Gray, Renzo Guerrini, Marie-Christine Guiot, William Harkness, Andrew G. Herzog, Linda Huh, Margaret J. Jackson, Thomas S. Jacques, Anna C. Jansen, Sigmund Jenssen, Michael R. Johnson, Dorothy Jones-Davis, Reetta Kälviäinen, Peter W. Kaplan, John F. Kerrigan, Autumn Marie Klein, Matthias Koepp, Edwin H. Kolodny, Kandan Kulandaivel, Ruben I. Kuzniecky, Ahmed Lary, Yolanda Lau, Anna-Elina Lehesjoki, Maria K. Lehtinen, Holger Lerche, Michael P. T. Lunn, Snezana Maljevic, Mark R. Manford, Carla Marini, Bindu Menon, Giulia Milioli, Eli M. Mizrahi, Manish Modi, Márcia Elisabete Morita, Manuel Murie-Fernandez, Vivek Nambiar, Lina Nashef, Vincent Navarro, Aidan Neligan, Ruth E. Nemire, Charles R. J. C. Newton, John O'Donavan, Hirokazu Oguni, Teiichi Onuma, Andre Palmini, Eleni Panagiotakaki, Pasquale Parisi, Elena Parrini, Liborio Parrino, Ignacio Pascual-Castroviejo, M. Scott Perry, Perrine Plouin, Charles E. Polkey, Suresh S. Pujar, Karthik Rajasekaran, R. Eugene Ramsey, Rahul Rathakrishnan, Roberta H. Raven, Guy M. Rémillard, David Rosenblatt, M. Elizabeth Ross, Abdulrahman Sabbagh, P. Satishchandra, Swati Sathe, Ingrid E. Scheffer, Philip A. Schwartzkroin, Rod C. Scott, Frédéric Sedel, Michelle J. Shapiro, Elliott H. Sherr, Michael Shevell, Simon D. Shorvon, Adrian M. Siegel, Gagandeep Singh, S. Sinha, Barbara Spacca, Waney Squier, Carl E. Stafstrom, Bernhard J. Steinhoff, Andrea Taddio, Gianpiero Tamburrini, C. T. Tan, Raymond Y. L. Tan, Erik Taubøll, Robert W. Teasell, Mario Giovanni Terzano, Federica Teutonico, Suzanne A. Tharin, Elizabeth A. Thiele, Pierre Thomas, Paolo Tinuper, Dorothée Kasteleijn-Nolst Trenité, Sumeet Vadera, Pierangelo Veggiotti, Jean-Pierre Vignal, J. M. Walshe, Elizabeth J. Waterhouse, David Watkins, Ruth E. Williams, Yue-Hua Zhang, Benjamin Zifkin, Sameer M. Zuberi
- Edited by Simon D. Shorvon, Frederick Andermann, Renzo Guerrini
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- Book:
- The Causes of Epilepsy
- Published online:
- 05 March 2012
- Print publication:
- 14 April 2011, pp ix-xvi
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3 - Trait Theories of Motivation
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- By D. Scheffer, Studied Psychology, University of Osnabrück, Germany, H. Heckhausen, Director, Max Planck Institute for Psychological Research in Munich
- Edited by Jutta Heckhausen, University of California, Irvine, Heinz Heckhausen, Max-Planck-Institut für Psychologische Forschung, Munich
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- Book:
- Motivation and Action
- Published online:
- 08 August 2009
- Print publication:
- 18 February 2008, pp 42-68
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Summary
From the Nomothetic to the Idiographic
Motivation emerges from the interaction of situational stimuli and dispositional characteristics. This chapter deals with the latter.
Dispositional factors of motivation are assumed to explain why some people show certain patterns of motivated behavior across situations, whereas others do not. Apart from specific situational stimuli, motivation is thus attributed to stable traits that are rooted in the individual personality, and that distinguish between people across situations and, to a certain extent, over time.
Individual dispositions to show certain patterns of motivation across situations have been given various labels in psychological research, reflecting very different notions of which and how many such dispositions there are, how they develop, and how they influence motivation. Accordingly, theories of motivation differ in terms of the relative importance they attribute to dispositional and environmental influences. Whereas the five-factor model focuses on endogenous dispositions and assumes the environment to play only a minor role, systems theory approaches emphasize the complex interactions between external stimuli and internal dispositions.
In this chapter we start with a simple model and gradually work our way toward a much more complex perspective on the role of dispositional factors in motivation. This does not mean to imply that one model is inherently preferable to another: all scientific theories of motivation aim to explain and predict in the most parsimonious and yet generally valid way possible why different people experience very different levels of tension and energy in similar situations, and why their behavior is directed toward such different goals.
Atracurium induced vasodilatation is not mediated by histamine in the isolated femoral artery of the rabbit
- D. M. de Jong, N. Hoogerwerf, G. J. Scheffer, J. J. de Lange, H. H. Ros, P. Sipkema
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- Journal:
- European Journal of Anaesthesiology / Volume 13 / Issue 4 / April 1996
- Published online by Cambridge University Press:
- 04 August 2006, pp. 333-339
- Print publication:
- April 1996
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Atracurium causes a decrease in systemic vascular resistance (SVR) and mean arterial blood pressure (MAP) which has been ascribed to histamine release. However, histamine receptor blockade does not prevent these decreases completely. The hypotensive side effects of atracurium may not only be caused by histamine. In this study we examined the vasoactive effects of atracurium with and without histamine receptor blockade in an isolated femoral artery preparation of the rabbit. We also investigated whether vasodilatation caused by atracurium depends on the presence of endothelial cells. Tyrode perfused, rabbit femoral arteries were constricted with noradrenaline (NA) to ±70% of their passive diameter. Endothelial function was checked with acetylcholine (ACh). The vessels were divided into two groups. In both groups the responses to histamine (1.0−10−6m) and atracurium (3.2−10−5m) were determined. In group one (n = 5), the histamine and atracurium responses were repeated during histamine receptor blockade. In group two (n = 5), the diameter responses to histamine and atracurium before and after endothelium removal were compared. Also, some vessel segments (n = 5) were histologically prepared and examined for mast cells. The vasodilatory responses to atracurium both with and without histamine receptor blockade were the same. Removal of endothelium caused an increase in the histamine response, while the dilating response to atracurium remained constant. We conclude that in the isolated femoral artery of the rabbit, atracurium induces vasodilatation that is not mediated by histamine release and cannot be prevented with histamine receptor blockade. The mechanism of atracurium induced dilation is independent of the endothelium and is located in the smooth muscle cell.