scholarly journals The effect of age on white light perception.

2018 ◽  
Vol 20 (2) ◽  
pp. 29-43
Author(s):  
Jacobus Gideon Van der Westhuyzen ◽  
Frederick Wilhelm Leuschner
Keyword(s):  
White Light ◽  
Test Procedure ◽  
Age Groups ◽  
Index Number ◽  
Light Sources ◽  
Colour Rendering ◽  
Effect Of Age ◽  
Psychophysical Test ◽  
Two Age Groups ◽  
The Way

The way that persons from different age groups experience “white light” is investigated. Human eye lens transmission changes spectrally with age and this may influence the way that humans from different ages experiences light. Such a difference may be important in industrial and medical environments. Two different age groups, one group younger than 40 years of age and another group older than 50 years of age were subjected to the same “white” definition task. A conventional single-booth setup was used where observers were able to adjust the intensity of four coloured LED’s. Results of the psychophysical test procedure were used to generate specifications of two light sources, as selected by the two age groups. The two age groups selected two very different light sources when tasked to achieve a “perception” of white. Results show that the older group prefers a source with a colour rendering index number of 89 and the younger group prefers a source with a colour rendering index number of 74. The sources selected by the two age groups specifies correlated colour temperature values of 5150 K for the older age group and 6592 K for the younger group.

Learned Helplessness in Physical Education: A Developmental Study of Causal Attributions and Task Persistence

1994 ◽  
Vol 13 (2) ◽  
pp. 108-122 ◽  
Author(s):  
Thomas J. Martinek ◽  
Joseph B. Griffith
Keyword(s):  
Learned Helplessness ◽  
Task Difficulty ◽  
Age Groups ◽  
Developmental Study ◽  
Age Group ◽  
Task Persistence ◽  
Behavioral Measures ◽  
Effect Of Age ◽  
Two Age Groups ◽  
And Task

The purpose of this study was to describe the effect of age on specific psychological and behavioral measures of learned-helpless and mastery-oriented students. The study consisted of two age groups, younger and older, of learned-helplessness and mastery-oriented students. Within each age group, learned-helpless and mastery-oriented students were compared in terms of attributional profiles and levels of task persistence during instruction. Students were asked to view videotapes of their performances, to describe how they thought they did on each task, and to give reasons for their performance. Responses were classified into four attributional categories: (a) ability, (b) effort, (c) task difficulty, and (d) environment or luck. Persistence was also determined by looking at the number of times students would attempt a task. Attributional profiles and task persistence associated with the leamed-helpless condition was more prevalent with the older group than with the younger group.

The effect of learner age on the interpretation of the nonverbal behaviors of teachers and other students in identifying questions in the L2 classroom

2016 ◽  
Vol 22 (1) ◽  
pp. 47-64 ◽  
Author(s):  
Nobuhiro Kamiya
Keyword(s):  
Elementary School ◽  
University Students ◽  
Age Groups ◽  
Nonverbal Behaviors ◽  
Linguistic Information ◽  
Video Clips ◽  
Short Video ◽  
The University ◽  
Effect Of Age ◽  
Two Age Groups

This study investigated how learners’ ages affect their interpretation of the nonverbal behaviors (NVBs) of teachers and other students in distinguishing between questions and statements in the second language (L2) classroom. After watching 48 short video clips without sound in which three L2 teachers asked a question or made a statement with or without gesture, 36 elementary school pupils and 30 university students judged whether they thought the teachers asked a question or made a statement along with their reasons. The findings show that, regardless of learners’ ages, L2 teacher’s gestures were found to help learners better identify questions. Furthermore, the six major types of NVBs used for judgments most frequently were identical across the two age groups regardless of the accuracy of their judgments. Nevertheless, incorrect judgments were made as often and sometimes even more often than correct judgments by applying the same assumptions. The effect of age was evidenced in that the university students were able to use a larger number of NVBs for correct judgments, and better distinguish questions and statements without linguistic information than the elementary school pupils. The data suggest that it is the learners’ (L2) classroom experience that seems to be playing the major role in yielding this difference. The study indicates that adult L2 learners are better able than children to incorporate and interpret NVBs of teachers as well as other students quantitatively and qualitatively.

The appreciation of LED-based white light sources by Dutch and Chinese people in three application areas

2018 ◽  
Vol 51 (3) ◽  
pp. 353-372 ◽  
Author(s):  
X Tang ◽  
C Teunissen
Keyword(s):  
White Light ◽  
Food Packaging ◽  
Skin Tone ◽  
Packaging Material ◽  
Light Sources ◽  
Chinese People ◽  
Fresh Food ◽  
Dutch Study ◽  
Colour Gamut ◽  
Colour Rendering

The aim of this study was to evaluate differences in appreciation for LED-based white-light sources between Dutch and Chinese people, when used for the illumination of three applications: fresh food, packaging material and skin tone. Furthermore, the contribution of the CIE special and general colour rendering indices ( Ri and Ra), a colour gamut measure ( Ga), and chroma changes for specific test-colour samples to perceived attractiveness was investigated. Thirty-four Dutch and 36 Chinese people assessed the attractiveness of the object appearance, with paired comparison experiments, for seven light sources at two CCT settings, 3000 K (Dutch and Chinese) and 4000 K (Chinese only), and a range of Ra and Ga values. It was found that for illuminating fresh food and packaging material, most Dutch and Chinese participants preferred light settings with an increased colour gamut. In contrast to colour rendering indices, the chroma change for the strong red test colour sample could be used to predict object attractiveness, but the established equations were different per application and culture. There was no clear relation between objective measures and skin tone preference for the Dutch study. Finally, Chinese participants did not like an increase in red saturation at 3000 K, but they allowed an increase at 4000 K.

scholarly journals Effect of Age and Sex on the Quality of Offal and Meat of the Wild Boar (Sus scrofa)

Animals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 660
Author(s):  
Agnieszka Ludwiczak ◽  
Joanna Składanowska-Baryza ◽  
Marek Stanisz
Keyword(s):  
Wild Boar ◽  
Crude Protein ◽  
Ph Value ◽  
Age Groups ◽  
Protein Ratio ◽  
Wild Boars ◽  
Effect Of Age ◽  
Age And Sex ◽  
Two Age Groups

The goal of the study was to examine the effect of age and sex on the quality of wild boar offal and meat. A number of 32 hunt-harvested animals was assigned to groups according to age (juveniles and sub-adults) and sex. The quality of offal (liver, kidneys, heart and tongue) and m. semimembranosus was examined. The pH value of m. semimembranosus ranged from 5.45 to 5.88. The highest pH was recorded in the kidney and the liver (6.32–6.54 and 6.12–6.31). The meat in the group of juveniles was brighter (p = 0.042), yellower (p = 0.039), showed a greater drip loss (p = 0.007), cooking loss (p = 0.039), and plasticity (p = 0.028), compared to the sub-adults. The extractable fat content in the m. semimembranosus and offal (p = 0.004), and water to crude protein ratio (p = 0.033), also differed between age groups. The results of the study show different quality attributes of offal and meat of wild boars from two age groups. The obtained quality measures suggest that the culinary and technological usefulness of offal and meat from the wild boars may differ according to the age of hunted animals.

FEEDLOT PERFORMANCE AND CARCASS COMPOSITION OF CULL COWS OF DIFFERENT AGES

1982 ◽  
Vol 62 (3) ◽  
pp. 845-854 ◽  
Author(s):  
W. C. GRAHAM ◽  
M. A. PRICE
Keyword(s):  
Compensatory Growth ◽  
Initial Level ◽  
Age Groups ◽  
Carcass Characteristics ◽  
Carcass Composition ◽  
Apparent Effect ◽  
Feedlot Performance ◽  
Cull Cows ◽  
Effect Of Age ◽  
Two Age Groups

Two experiments were conducted to study the effect of age on the feedlot performance and carcass characteristics of cull range cows. In the first experiment, 87 cull cows of three breed-types (Hereford, Beef Composite and Dairy Composite) and three age groups (young, intermediate and mature) were fed a grain diet for 0, 8 or 16 wk. Rate of gain was higher (P < 0.01) in the first than in the second 8 wk (1.80 vs. 1.13 kg−1∙head−1∙day−1). This was accompanied by an increase (P < 0.01) in feed:gain ratio (6.9 vs. 12.8). There were no significant differences among breeds or age groups in feedlot performance or carcass characteristics. Carcass weight increased with age (P < 0.01) and length (P < 0.01). When adjusted to a common carcass length, mature cows had smaller rib eye areas than the other cows. In the second experiment, 37 cull range cows of predominantly Angus breeding, and representing two age groups (young and mature) were used. Twenty-nine of these cows were fed a grain diet ad libitum for 8 wk before slaughter. Young cows gained 1.61 kg∙head−1∙day−1 compared with 1.29 kg∙head−1∙day−1 for the mature cows. The initial level of body fat had no apparent effect on subsequent feedlot performance. The 9th- 10th- 11th rib joints of the younger cows contained less bone (P < 0.01), and had higher muscle:bone ratios (P < 0.01) than those from the mature cows. Key words: Cull cows, feedlot performance, compensatory growth, carcass composition

scholarly journals EFFECT OF AGE ON SOME ASPECTS OF SULFATE METABOLISM IN THE RAT

1954 ◽  
Vol 99 (3) ◽  
pp. 283-298 ◽  
Author(s):  
Dominic D. Dziewiatkowski
Keyword(s):  
Serum Proteins ◽  
Age Groups ◽  
Intraperitoneal Dose ◽  
Sulfate Metabolism ◽  
Old Rats ◽  
Specific Activities ◽  
The Difference ◽  
Effect Of Age ◽  
Two Age Groups

S35-labelled sodium sulfate was administered to rats 10, 30, and 300 days old in an intraperitoneal dose of 0.3 µc. per gm. of body weight. Representative animals of each age were sacrificed 12, 24, 48, and 96 hours after injection. The concentration of sulfur-35 in the pooled sera of the 10-day-old rats was found to be strikingly higher than the level in the sera of the 30-day-old and the 300-day-old rats, while the levels of sulfur-35 in the sera of rats in the latter two age groups were similar. The difference was not explained by the differences in binding of sulfate by serum proteins. Although no binding could be detected when sulfate was added to serum in vitro, a substantial fraction, up to 80 per cent by the 96th hour, was observed to be bound after injection into the living rat. The 10-day-old rats differed from the older ones in having lower levels of serum proteins and lesser amounts of bound sulfate. The non-dialyzable sulfur-35 was associated to the largest extent with the albumin component in the sera. The age of the rats found expression in the specific activities of the sulfate-sulfur of mucopolysaccharides isolated from the skeletons, pelts, and viscera. The highest specific activities were observed in the mucopolysaccharides isolated from the tissues of the youngest rats; the lowest in those from the oldest rats. Though the maximum concentration was rapidly attained in the mucopolysaccharides from the various tissues in each of the age groups, the subsequent decreases in concentration were slow. Radiochemical analyses for sulfur-35 in ends and shafts of femurs and radioautographs of humeri supported the assumption that the labelled sulfate had been incorporated into the chondroitin sulfate of growing cartilage.

Effect of Age, Sex, and Race Distance on Front Crawl Stroke Parameters in Subelite Adolescent Swimmers During Competition

2015 ◽  
Vol 27 (3) ◽  
pp. 334-344 ◽  
Author(s):  
Shilo Dormehl ◽  
Conor Osborough
Keyword(s):  
Significant Interaction ◽  
Age Groups ◽  
Stroke Index ◽  
Front Crawl ◽  
Stroke Length ◽  
Video Footage ◽  
Pacing Strategies ◽  
Older Adolescents ◽  
Effect Of Age ◽  
Two Age Groups

The aims of this study were to determine the effect of age, sex and race distance on velocity (v), stroke rate (SR), stroke length (SL) and stroke index (SI) of subelite adolescent swimmers in competition, and to investigate their pacing strategies during the 100-m and 200-m events. Video footage of 112 adolescent swimmers (56 female; 56 male), competing in the 100-m and 200-m freestyle events, in two age groups (12–14; 15–18 years) was recorded and subsequently analyzed. A MANOVA showed that all stroke parameters significantly differed between sexes and between race distances. The older adolescents had a higher v, a longer SL and a greater SI (p < .01) than the younger adolescents. There were significant interaction effects between age and sex for v, SL and SI. Most adolescents had a SL that was within 7% of that reported for 1992 Olympians, but had up to 16% lower SRs. Separate Friedman’s ANOVAs showed that SL differed between successive race quarters for both age groups, both sexes and both race distances. It is likely that physical immaturity, inexperience in competition pacing and within-race fatigue strongly influence the performances of subelite adolescent front crawl swimmers.

scholarly journals Influence of Peak Wavelengths on Properties of Mixed-LED White-Light Sources

2010 ◽  
Vol 2010 ◽  
pp. 1-8 ◽  
Author(s):  
Snjezana Soltic ◽  
Andrew N. Chalmers
Keyword(s):  
Light Source ◽  
White Light ◽  
Light Sources ◽  
Peak Wavelength ◽  
White Light Source ◽  
Luminous Efficacy ◽  
Colour Temperature ◽  
Colour Rendering

The purpose of this investigation is to quantify the influence of the peak wavelength shifts in commercially available LEDs on the characteristics of the mixed-LED white-light sources. For this purpose, a tetrachromatic spectrum was optimized and then subjected to deviations in the peak wavelengths. A total of 882 combinations of peak wavelength values were evaluated, and the results are reported in terms of correlated colour temperature, colour-rendering properties, and radiant luminous efficacy. The results show that there can be significant changes in the characteristics of the source under these conditions. Such changes are highly likely to present problems when dealing with applications where an effective and accurate white-light source is important.

Effects of Age, Sex, and Disorder on Voice Range Profile Characteristics of 230 Children

2003 ◽  
Vol 112 (6) ◽  
pp. 540-548 ◽  
Author(s):  
Floris L. Wuyts ◽  
Louis Heylen ◽  
Raoul Rooman ◽  
Fons Mertens ◽  
Paul H. Van de Heyning ◽  
...  
Keyword(s):  
Age Groups ◽  
Morphological Characteristics ◽  
Vocal Performance ◽  
Healthy Children ◽  
Range Profile ◽  
Profile Characteristics ◽  
Voice Range ◽  
The Voice ◽  
Effect Of Age ◽  
Two Age Groups

In this study, the effect of age, sex, and disorder on the vocal performance of 230 children 6 to 11 years of age was investigated by means of the voice range profile (VRP). Ninety-four control children and 136 children with disorders were studied. The VRPs were quantitatively described by frequency and intensity characteristics, as well as by morphological characteristics. Significant differences between healthy children and children with disorders were found. Age has a different effect in girls than in boys regarding vocal performance. Most of the characteristics for the healthy girls change gradually over the period from 6 to 11 years. For the healthy boys, however, Two age groups can be identified: one below and one above 8 years of age. It is hypothesized that the androgen dehydroepiandrosterone (DHEA) and its sulfate may play a role in this phenomenon.

The Effect of Age on Decision Making According to the Iowa Gambling Task

2012 ◽  
Vol 15 (2) ◽  
pp. 480-486 ◽  
Author(s):  
Janaína Castro Núñez Carvalho ◽  
Caroline de Oliveira Cardoso ◽  
Daniela Shneider-Bakos ◽  
Christian Haag Kristensen ◽  
Rochele Paz Fonseca
Keyword(s):  
Decision Making ◽  
Iowa Gambling Task ◽  
Age Groups ◽  
Elderly Adults ◽  
Gambling Task ◽  
Decision Making Processes ◽  
Brain Changes ◽  
The One ◽  
Effect Of Age ◽  
Two Age Groups

Aging has been associated with several brain changes that often affect the cognitive functioning of adults, but changes in executive functions, particularly in the field of decision making, have not been fully investigated. The Iowa Gambling Task (IGT) is a widely used tool to evaluate decision making, but little is known about the effect of age on its results. This study used the IGT and compared healthy young (n= 40) and elderly (n = 40) adults to evaluate their decision making processes. There were significant differences in the learning curve of the two age groups, but no difference in overall IGT performance. The results for the first IGT block were different from those of the rest of the task, and the group of elderly adults had a better performance in this block. Elderly adults also showed a preference for deck A, the one that resulted in greater losses. Findings confirmed the results of other studies, which reported that the IGT block score is the variable with the greatest sensitivity to age in this instrument.

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