Search results for " experimental"
showing 10 items of 3530 documents
Chemomechanical preparation by hand instrumentation and by Mtwo engine-driven rotary files, an ex vivo study
2011
Objective: To compare the disinfecting efficacy of the sodium hypochlorite irrigation by root canal preparation with stainless steel hand files, taper 0.02 and nickel-titanium Mtwo files with taper 0.04-0.06. Study Design: 40 extracted human teeth were sterilized, and then inoculated with Enterococcus faecalis (ATCC 29212). After 6 day incubation time the root canals were prepared by hand with K-files (n=20) and by engine-driven Mtwo files (VDW, Munich, Germany) (n=20). Irrigation was carried out with 2.5% NaOCl in both cases. Samples were taken and determined in colony forming units (CFU) from the root canals before and after the preparation with instruments #25 and #35. Results: Significa…
Psychobiosocial Experiences in Sport : Development and Initial Validation of a Semantic Differential Scale
2021
Abstract Objectives To develop and validate the Psychobiosocial Experience Semantic Differential scale in sport (PESD-Sport), a new measure to assess discrete emotions and performance-related experiences in sport as conceptualized within the individual zones of optimal functioning (IZOF; Hanin, 2000, 2007, 2010) framework. Method In Study 1, we developed a preliminary 53-item version of the scale using a semantic differential format in the construction of the items pertaining to 12 psychobiosocial modalities. We chose this format to attain a clear representation of psychobiosocial states between opposites along perceived performance functionality (i.e., functional, dysfunctional). The preli…
Modeling of the viscoelastic behavior of paving bitumen using fractional derivatives
2009
The paving grade bitumen used in the production of asphalt mixtures for road construction is significantly able to affect the in-service performances of flexible road pavements. It has been proved that, when subjected to loading conditions comparable with most pavement operating conditions, bituminous binders behave as linear visco-elastic materials. The aim of this paper is to propose a model based on fractional differential equations which is able to describe the behavior of bituminous binders in the linear viscoelastic range. Shear creep testing and creep recovery testing were carried out over a range of temperatures and by applying a stress level which makes it possible to maintain the …
The spanish body image state scale: factor structure, reliability and validity in a colombian population
2019
ObjectiveBody image is a construct highly dependent on culture and ethnicity. Furthermore, recent studies reveal that body image is not only a trait, but also a momentary state subject to change in diverse situational contexts. However, cultural influences on momentary body image have not been sufficiently investigated. To assess the influence of Latin American culture on momentary body image and to enable its comparison to Western countries, the Spanish translation of an existing state body image scale such as the Body Image States Scale (BISS) is needed. In addition, the factor structure, reliability and general validity of the Spanish BISS (S-BISS) should be evaluated prior to its applic…
Extremely Low Frequency Magnetic Fields Do Not Affect LTP-Like Plasticity in Healthy Humans.
2020
Introduction: Several studies explored, in vitro, the biological effects of extremely low-frequency magnetic fields (ELF-MFs) and reported the induction of functional changes in neuronal activity. In particular, ELF-MFs can influence synaptic plasticity both in-vitro and in animal models. Indeed, some studies reported an increase in long-term potentiation (LTP) whereas others suggested its reduction. However, no specific study has investigated such effect in humans. Aims: To evaluate whether ELF-MFs affect the propensity of the human cortex to undergo LTP-like plasticity. Methods: We designed a randomized, single-blind, sham-controlled, cross-over study on 10 healthy subjects. Cortical plas…
Don't throw away your printed books: A meta-analysis on the effects of reading media on reading comprehension
2018
Abstract With the increasing dominance of digital reading over paper reading, gaining understanding of the effects of the medium on reading comprehension has become critical. However, results from research comparing learning outcomes across printed and digital media are mixed, making conclusions difficult to reach. In the current meta-analysis, we examined research in recent years (2000–2017), comparing the reading of comparable texts on paper and on digital devices. We included studies with between-participants (n = 38) and within-participants designs (n = 16) involving 171,055 participants. Both designs yielded the same advantage of paper over digital reading (Hedge's g = −0.21; dc = −0.2…
Positive Technologies for Improving Health and Well-Being
2017
In the last 20 years there have been two important developments of great importance to the field of psychological treatments. On the one hand, this meant the movement of positive psychology, and on the other, the introduction of information and communication technologies (ICT) to improve the daily clinical practice. In this paper a new field of study that attempts to strengthen ties and build bridges between them is introduced: Positive Technologies. This perspective seeks to promote the use of technology to foster personal growth and the development of human virtues and strengths, thus contributing to social and cultural development. In this chapter, we present four positive technologies: …
23. Resting state functional magnetic resonance imaging analysis of the brain of pathological gamblers
2018
Purpose Gambling disorder has been recently reclassified under the category “substance-related and addictive disorders”. Recent studies performed through functional MRI (fMRI) have shown that the perseverance of some behaviors can alter brain activation [1] , [2] . In this work we aim at investigating functional connectivity changes in pathological gamblers (PGs) in comparison to healthy controls (HCs) by means of resting state functional Magnetic Resonance Imaging (rs-fMRI). Methods and materials Thirteen HCs and fourteen PGs were recruited (all right handed males; drugs free; mean age 36 ± 10 yrs). All acquisitions were performed through a 1,5 T MRI scanner using a 8-channels phased-array…
2020
To successfully learn using open Internet resources, students must be able to critically search, evaluate and select online information, and verify sources. Defined as critical online reasoning (COR), this construct is operationalized on two levels in our study: (1) the student level using the newly developed Critical Online Reasoning Assessment (CORA), and (2) the online information processing level using event log data, including gaze durations and fixations. The written responses of 32 students for one CORA task were scored by three independent raters. The resulting score was operationalized as “task performance,” whereas the gaze fixations and durations were defined as indicators of “pr…