[Importance, construction, contents and application of operational schemes in dental technical laboratories].
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Laboratories, Dental↗
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Results for “Task Performance and Analysis”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
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Management engineering-a method to improve productivity.
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Communication↗
[Organigation of the working time in the public health service--methodical principles for analyses of the working time in public health and social service facilities].
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Community Health Services↗
Ergonomics.
The ergonomist seeks to reduce incidence and severity of occupational musculoskeletal disorders as well as improve productivity and work quality. Thus, ergonomics addresses both the employee and employer.
Ergonomics↗
Evidence that the slowing caused by acute hypoxia is modality dependent.
BACKGROUND: AFM (Additive Factors Method) experiments conducted with visual stimuli suggest that the slowing produced by acute hypoxia is located at the earliest preprocessing stage of information processing and that later stages are unaffected (the bottleneck hypothesis). METHODS: To determine the contribution of degraded visual functioning to slowing, we bypassed this modality and measured reaction time in an AFM paradigm to auditory (Experiment 1) and kinesthetic (Experiment 2) stimuli. In both experiments hypoxia was induced with low oxygen mixtures and arterial blood oxygen saturation (SaO2) was controlled at 65%. Task difficulty was manipulated in Experiment 1 with tones that differed in intensity and in Experiment 2 with lifted cylinders that differed in weight. RESULTS: The results for Experiment 1 showed an interaction between task difficulty and hypoxia, indicating slowing of the preprocessing stage. Slowing was not found in Experiment 2. The absence of slowing in Experiment 2 is surprising and indicates that slowing may be confined to vision and audition and may not involve later, more central, stages. We discuss the need to measure cerebral oxygenation in order to understand the sharp differences between the the bottleneck hypothesis, developed by controlling SaO2, and the more traditional behavioral model which postulates multiple cognitive deficits.
Acute Disease↗
In-vehicle workload assessment: effects of traffic situations and cellular telephone use.
PROBLEM: Assessment of drivers' on-road workload is an important traffic safety consideration. This study was conducted to examine the effects of cellular phone communication on driving performance, with particular emphasis on variations in task demand in different traffic situations. METHOD: Twelve participants were asked to drive on urban roads and motorways with or without concomitant mathematical-addition tests relayed via cellular phone. Measurements included task and driving performance, physiological responses, and compensatory behavior. RESULTS: Analysis of task performance revealed that mean response time was markedly increased (11.9%) for driving on urban roads compared to motorways. The mean driving speed only decreased 5.8% in the presence of phone tasks in comparison to normal driving without distractions. In addition, overall physiological workload increased through compensatory behavior in response to the phone tasks. CONCLUSIONS: Driving with phone use in different traffic environments induced measurable variations in driver workload. IMPACT ON INDUSTRY: When faced with heavy traffic, a greater safety margin is typically adopted, with more lowered driving speed and restricted phone use, and it can be assumed that there is a general trade-off between tasks to preserve driving safety.
Adult↗
Mental and physical effort affect vigilance differently.
Both physical and mental effort are thought to affect vigilance. Mental effort is known for its vigilance declining effects, but the effects of physical effort are less clear. This study investigated whether these two forms of effort affect the EEG and subjective alertness differently. Participants performed a physical task and were subsequently presented with a mental task, or vice versa. Mental effort decreased subjective alertness and increased theta power in the EEG. Both results suggest a vigilance decline. Physical effort, however, increased subjective alertness and alpha and beta1 power in the EEG. These findings point towards an increase in vigilance. Beta2 power was reduced after physical effort, which may reflect a decrease in active cognitive processing. No transfer effects were found between the effort conditions, suggesting that the effects of mental and physical effort are distinct. It is concluded that mental effort decreases vigilance, whereas physical effort increases vigilance without improving subsequent task performance.
Adult↗
No evidence of association between Catechol-O-Methyltransferase (COMT) Val158Met genotype and performance on neuropsychological tasks in children with ADHD: a case-control study.
BACKGROUND: Several studies have suggested an association between the functional Val158Met polymorphism in the Catechol-O-Methyltransferase (COMT) gene and neurocognitive performance. Two studies showed that subjects with the low activity Met allele performed better on the Wisconsin Card Sorting Test (WCST) and another study found an effect on processing speed and attention. METHODS: We set out to examine the association between the Val158Met polymorphism and performance on neurocognitive tasks including those tapping working memory, attention and speed, impulsiveness and response inhibition in a sample of 124 children with ADHD. Task performance for each genotypic group was compared using analysis of variance. RESULTS: There was no evidence of association with performance on any of the neurocognitive tasks. CONCLUSIONS: We conclude that Val158Met COMT genotype is not associated with neurocognitive performance in our sample.
Adolescent↗
Effects of anxiety on attentional allocation and task performance: an information processing analysis.
An information processing signal detection methodology was employed to examine attentional allocation and its correlates in both normal comparison (NC) and generalized anxiety disorder (GAD) participants. In particular, the impact of neutral distractor and negative feedback cues on performance of an attention vigilance task was investigated. Individuals with GAD (N = 15) evidenced impaired performance on an attention vigilance task relative to NC participants (N = 15) when neutral distractor cues were presented. Contrary to prediction, no group differences in performance were detected under conditions in which participants were presented negative feedback cues they were told were relevant to their performance. Instead, GAD participants exhibited improvement during the experimental task such that their performance was equivalent to NC participants. Across trials, the clinically anxious group endorsed significantly higher levels of worry and negative affectivity; however, they failed to respond with concomitant physical arousal (e.g. increased muscle tension). These data are discussed within the context of Eysenck and Calvo's (1992, Cognition and Emotion, 6, 409-434) processing efficiency theory. Additionally, the results of this investigation provide support for Barlow's (1988, Anxiety and its disorders: The nature and treatment of anxiety and panic) conceptualization of anxiety as requiring the interaction of cognitive schema and physiological arousal.
Adolescent↗
More practice does not necessarily enhance transfer of learning: evidence and interpretations.
The purpose of this study was to investigate what was learned and transferred of a criterion task using a transfer task and a self-paced procedure. Based on the results of two previous studies, five durations of practice were specifically selected to examine what can be transferred to a new task after different amounts of practice (40, 75, 100, 125, and 150 acquisition trials) on a criterion task. The criterion task required subjects to practice finding an 8-in. line with no fixed starting and ending points from left to right. The transfer task was different from the criterion task in two dimensions, distance (10-in. line) and direction (right to left). 50 volunteers were randomly assigned into 5 groups. Appropriate 5 x 2 (groups by blocks of practice) analyses of variance and a priori contrasts were conducted for all dependent variables (absolute error, variable error, movement time, KR-delay, post-KR interval, intertrial interval, interstimulus interval, and KR-delay by post-KR interval ratio) to examine the effects of terminal acquisition of the criterion task on the initial performance of the transfer task. Analysis indicated that, during practice, participants developed a functional interaction between performance characteristics and chronological profile of KR-delivery of the criterion task that was transferable to the transfer task. Also, practice beyond a certain point was detrimental to the ability to transfer what was learned.
Adult↗
Effects of work task cues and play task cues on information processing, judgment, and motivation.
How task cues affect cognition, attitudes, and behavior was explored in this laboratory study with 82 master of business administration students. Linguistic analysis of responses to the same puzzle task, cued as either work or play, revealed that task cues influenced how information was perceived and was used to form judgments and to shape behavioral responses. Ss performing work tasks attended more to information about the quantity of their performance and made more streamlined, goal-directed responses. Ss performing play tasks attended more to information about the quality of their performance; made more elaborated, image-laden responses; and were more intrinsically motivated. Links among task cues, cognitive processes, and performance were explicated through path analysis. Task cues affected performance outcomes indirectly by instantiating associated cognitive orientations: a means orientation in play and an ends orientation in work.
Adult↗
Revisiting inhibitory control across the life span: insights from the ex-Gaussian distribution.
Changes in inhibitory control occur across the life span and have been associated with alterations in prefrontal function. In this study, ex-Gaussian analysis was used to reexamine data from an inhibitory control task. Participants (ages 6 to 82 years) composed three groups: children, young adults, and older adults. In fitting the ex-Gaussian distribution to reaction time data, estimates of three parameters were obtained: mu (mu), reflecting average performance; sigma (sigma), reflecting variability in performance; and tau (tau), reflecting extremes in performance. Older adults differed from young adults in terms of mu, sigma, and tau. For children, mu and tau values were comparable to those of young adults; sigma, however, was different. Thus, inhibitory changes in older adults were due to slower, more variable, and more extreme responding. Inhibitory changes in children were due only to more variable responding. These findings suggest that different mechanisms underlie age-related changes in inhibitory control during different epochs of the life span. This study demonstrates that the ex-Gaussian approach provides a finer level of analysis than data analytic approaches typically used in neuropsychological research.
Adolescent↗
Assessing task "burden" of daily activities requiring upper body function among women following breast cancer treatment.
GOALS OF WORK: To determine which individual or groups of "upper-body" daily tasks are considered most burdensome to women following breast cancer treatment, and to assess whether certain patient or treatment characteristics influence task burden. PATIENTS AND METHODS: A convenience sample of breast cancer survivors (n =619) completed a self-administered questionnaire regarding 48 daily tasks requiring upper-body function. Women were asked to rate how frequent and physically demanding each task was using a five-point Likert scale, and the product of task frequency and physical demand determined overall task burden. Tasks were ranked to identify the most burdensome individual tasks, while a factor analysis was performed to define independent constructs (groupings) among the tasks. Multiple linear regression models were fitted to consider the independent influences on task groups of various participant characteristics. MAIN RESULTS: Factor analysis identified seven distinct task groups and the individual tasks considered most burdensome fell in five of these groups, specifically whole body, flexibility, carrying/upper-body strength, hand and weighted flexion tasks. Having lymphoedema or poor fitness was associated with upper-body disability involving all seven task groups, whereas other patient and treatment characteristics were related only to certain types of activities. CONCLUSIONS: Breast cancer survivors report difficulty with a range of upper-body tasks, particularly if they also have lymphoedema or poor fitness. Using all or some of the tasks within the reported constructs in a questionnaire format, or the functional requirements of the most burdensome tasks to develop more objective and quantitative measures, would provide a solid base for the measurement of upper-body function in women with breast cancer.
Activities of Daily Living↗
Dynamic wrist motion analysis using six degree of freedom sensors.
Dynamic motion analysis of the wrist in the past has been a tedious and often impossible task to undertake. However, such motion analysis is now practical with the use of the McDonnell Douglas 3Space Digitizer and Macintosh microcomputer. The feasibility of using this system with multiple electromagnetic sensors for upper extremity kinematics analysis has been previously described by our laboratory. This work has now been extended to the dynamic analysis of wrist motion during performance of a work task by placing one sensor on the hand and the other on the distal forearm. The 3Space Digitizer source creates a low-frequency magnetic field. Sensors placed within the field have a specific position and orientation with respect to a coordinate system defined by the source. The x, y, z coordinates and theta, phi, psi orientation angles of the sensors on the subject's extremity are measured during task performance at a rate of approximately 19 readings per second. Analysis of this data provides a "motion signature" of the task under study. After the task completion the data obtained from the digitizer (orientation of the hand and forearm with respect to the digitizer's source) is stored on a computer disk and then reduced using mathematical transformations to obtain instantaneous radial/ulnar deviation (RUD), flexion/extension (FE), and supination/pronation (SP). The transformed data is displayed graphically as RUD vs. time, or FE vs. time and SP vs. time for each given task. A frequency analysis for each task performed is obtained with the use of the Macintosh microcomputer and a Fast Fourier Transform.(ABSTRACT TRUNCATED AT 250 WORDS)
Humans↗
[Multivariate discriminant analysis for assessing mental workload during duel task operation].
In order to investigate the efficiency of multivariate discriminant analysis in the assessment of mental workload during dual task operations, various psychophysiological indices and performance were recorded. The dual task consisted of the primary visual tracking task and the secondary Oddball task. The results indicated that tracking error, latency of P3 and IBI of HR correlated well with the mental workload and the multivariate discriminant analysis succeeded in classifying the levels of mental workload with higher conformation rate than those using the single index. It suggests that multivariate discriminant analysis is meaningful in the assessment of mental workload under dual task situations.
Aerospace Medicine↗
Studies of helicopter pilot performance. II. The analysis of task dimensions.
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Aviation↗
Predicting age-related dual-task effects with individual differences on neuropsychological tests.
This study examined the relation of dual-task performance to individual differences on neuropsychological tests. Neuropsychological test scores from 16 young and 16 older participants were simultaneously submitted to a factor analysis that yielded 2 factors (Attention/Executive and Memory) that differed by age and 2 (Motor Speed and Cognitive Status) that did not. Regression analyses revealed that these factors were significant predictors of performance on a delayed visual recognition task, but the relationship varied as a function of task condition. The Memory and Motor Speed factors were the strongest predictors of single-task performance, but the Attention/Executive factor was the most important predictor of dual-task performance. The authors conclude that compromised central executive may underlie age-related decline in dual-task performance.
Adult↗
Combined and interacting effects of hand and head movement delays on discrete manual performance in a virtual environment.
Transmission delays occur when a virtual environment responds to the hand and head movements of an operator. The effects of hand and head-related delays on discrete manual performance was investigated experimentally and compared. Imposed hand and head-related pure delays equal to or greater than 110 ms and 220 ms, respectively, significantly increased hand Movement Time (MT). The effect of hand-related delays was greater than that of head-related delays of the same magnitude. A regression model describing the combined effects of both delays on MT is reported (R(2) = 0.95). Analyses of the interactions among delays, target width, and distances have shown the need to adopt the traditional classification of delays into (1) control delay, and (2) display delay. The use of this taxonomy and the regression analyses to describe and explain the effects of individual and combined effects of delays on discrete target-reaching task performance in virtual environments are discussed.
Ergonomics↗