Search results for " Statistical"
showing 10 items of 1649 documents
Kinematics of obstacle clearance in the rat
2010
Although the rat has become the favourite animal model in preclinical research on locomotion, studies designed to assess the strategy used by rats to avoid obstacle are lacking. Using an optoelectronic 3D motion analysis system, we therefore, compared the step pattern, timing and length variables of locomotor cycles, trajectories and joint angles of limbs when rats step between and over obstacles (3 cm-high) fixed on a treadmill belt (25 cm/s). Motion in all four limbs of adult animals with an initial age of 11 weeks was serially recorded for a period of 10 weeks. The results showed that obstacle clearance is associated with the reorganization of the basic step pattern resulting in increase…
Sperm kinematic subpopulations of the American crocodile (Crocodylus acutus)
2021
There has been very limited use of computer assisted semen analysis (CASA) to evaluate reptile sperm. The aim of this study was to examine sperm kinematic variables in American crocodile (Crocodylus acutus) semen samples and to assess whether sperm subpopulations could be characterized. Eight ejaculates (two ejaculates/male) from four sexually mature captive crocodiles were obtained. An ISAS®v1 CASA-Mot system, with an image acquisition rate of 50 Hz, and ISAS®D4C20 counting chambers were used for sperm analyses. The percentages of motile and progressively motile spermatozoa did not differ among animals (P > 0.05) but there was a significant animal effect with regards to kinematic variables…
Fluency and rule breaking behaviour in the frontal cortex
2020
Design (DF) and phonemic fluency tests (FAS; D-KEFS, 2001) are commonly used to investigate voluntary generation. Despite this, several important issues remain poorly investigated. In a sizeable sample of patients with focal left or right frontal lesion we established that voluntary generation performance cannot be accounted for by fluid intelligence. For DF we found patients performed significantly worse than healthy controls (HC) only on the switch condition. However, no significant difference between left and right frontal patients was found. In contrast, left frontal patients were significantly impaired when compared with HC and right frontal patients on FAS. These lateralization findin…
Psychometric Properties of Spanish Version Student Utrecht Work Engagement Scale (UWES–S–9) in High-school Students
2019
AbstractThe Utrecht Work Engagement Scale (UWES) is a self-report instrument widely used, both in the original and its abbreviated version of nine items, to assess the work -UWES, UWES–9– and academic engagement -UWES-S, UWES–S–9–. The present study examines factor structure of the UWES–S–9 using confirmatory factor analysis (CFA), its convergent validity and invariance across sex and age groups in a sample of 626 Spanish high school students. The results support an unidimensional conceptualization of engagement (S-Bχ2/df = 5.29; CFI = .96; NNFI = .94; RMSEA = .083; IFI = .96; AIC = 82.21; BIC = 267.38), revealed an essentially invariant structure of the UWES–S–9 across the sex, ΔS-Bχ2(Δ6) …
Continuity From Prelinguistic Communication to Later Language Ability: A Follow-Up Study From Infancy to Early School Age.
2016
Purpose This longitudinal study examined the development of prelinguistic skills and the continuity of communication and language from the prelinguistic stage to school age. Method Prelinguistic communication of 427 Finnish children was followed repeatedly from 6 to 18 months of age ( n = 203–322 at ages 6, 9, 12, 15, and 18 months), and its associations with language ability at ages 2;0 ( n = 104), 3;0 ( n = 112), 4;7 ( n = 253), 5;3 ( n = 102), and 7;9 ( n = 236) were examined using latent growth curve modeling. Results Prelinguistic development across several skills emerged as a rather stable intraindividual characteristic during the first 2 years of life. Continuity from prelinguistic …
The SF-8 Spanish Version for Health-Related Quality of Life Assessment: Psychometric Study with IRT and CFA Models.
2018
AbstractThe aim of current research is to analyze the psychometric properties of the Spanish version of the SF–8, overcoming previous shortcomings. A double line of analyses was used: competitivestructural equations modelsto establish factorial validity, andItem Response theoryto analyze item psychometric characteristics and information. 593 people aged 60 years or older, attending long life learning programs at the University were surveyed. Their age ranged from 60 to 92 years old. 67.6% were women. The survey included scales on personality dimensions, attitudes, perceptions, and behaviors related to aging. Competitive confirmatory models pointed out two-factors (physical and mental health…
A Two-Phase Model of Resource Allocation in Visual Working Memory
2017
Two broad theories of visual working memory (VWM) storage have emerged from current research, a discrete slot-based theory and a continuous resource theory. However, neither the discrete slot-based theory or continuous resource theory clearly stipulates how the mental commodity for VWM (discrete slot or continuous resource) is allocated. Allocation may be based on the number of items via stimulus-driven factors, or it may be based on task demands via voluntary control. Previous studies have obtained conflicting results regarding the automaticity versus controllability of such allocation. In the current study, we propose a two-phase allocation model, in which the mental commodity could be al…
Strength training in old age: adaptation of antagonist muscles at the ankle joint.
2005
The purpose of this study was to determine whether strength training could reduce the deficit in plantarflexion (PF) maximal voluntary contraction (MVC) torque observed in previous studies in older subjects relative to young adults. Accordingly, the effects of a 6-month strength training program on the muscle and neural properties of the major muscle groups around the ankle were examined. PF and dorsiflexion (DF) isometric MVC torques were measured and surface electromyographic activity of the triceps surae and tibialis anterior muscles was recorded. The strength training program was very effective in improving strength in PF (+24.5%), and it thus reduced the DF-to-PF MVC torque ratio; in a…
''Motor Resonance Mechanisms Are Preserved In Alzheimer's Disease Patients''
2012
Bisio, A. | Casteran, M. | Ballay, Y. | Manckoundia, P. | Mourey, F. | Pozzo, T.; International audience; ''This study aimed to better characterize the sensorimotor mechanisms underlying motor resonance, namely the relationship between motion perception and movement production in patients suffering from Alzheimer's disease (AD). This work first gives a kinematic description of AD patients' upper limb movements, then it presents a simple paradigm in which a dot with different velocities is moved in front of the participant who is instructed to point to its final position when it stopped. AD patients' actions, as well as healthy elderly participants, were similarly influenced by the dot veloc…
Hospital readmission rates: signal of failure or success?
2013
AbstractHospital readmission rates are increasingly used as signals of hospital performance and a basis for hospital reimbursement. However, their interpretation may be complicated by differential patient survival rates. If patient characteristics are not perfectly observable and hospitals differ in their mortality rates, then hospitals with low mortality rates are likely to have a larger share of un-observably sicker patients at risk of a readmission. Their performance on readmissions will then be underestimated. We examine hospitals’ performance relaxing the assumption of independence between mortality and readmissions implicitly adopted in many empirical applications. We use data from th…