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Sample records for age karnofsky performance

  1. Correlation between Karnofsky Performance Status Scale and Short-Form Health Survey in patients on maintenance hemodialysis.

    PubMed Central

    Arogundade, Fatiu A.; Zayed, Bahaa; Daba, Maryam; Barsoum, Rashad S.

    2004-01-01

    BACKGROUND: Assessment of quality of life is vital inmonitoring response to various treatment measures. Various instruments, which include both generic and disease-specific instruments, are used in the assessment of health-related quality of life (HRQOL). In this study, we compare two commonly used generic instruments. OBJECTIVES: The objective of this study was to compare two generic instruments, the Karnofsky Performance Status Scale and the SF-36 Health Survey in hemodialysis (HD) patients. The study also aims to find out the association (if any) between HRQOL scores using these two scales and various clinical and biochemical parameters. MATERIALS AND METHODS: Sixty-two maintenance HD patients were recruited after informed consents were obtained. Detailed sociodemographic data was obtained. They were assessed during their regular HD sessions. Serum chemistry (which included serum urea, creatinine, Na+, K+, HCO3-, Ca2+, Po4(2-)), albumin, globulin, total protein and hemoglobin (g/dl) were assessed in all the patients. Adequacy of HD was assessed using second-generation Daugirdais formula. HRQOL was assessed using the Karnofsky and SSF-36 instruments and the scores collated and compared. Data was analyzed using SPSS version 10. RESULTS: Fifty-five patients completed the study (27 males and 28 females, mean age 40.76 +/- 11.05 years and age range of 20-65 years). There was a significant positive correlation between Karnofsky scores and all eight SF-36 domains, but only physical functioning, social functioning and role limitation due to emotional problems maintained the significance on multiple regression analysis. The serum creatinine and hemoglobin postively correlated with physical function, bodily pain, social functioning and Karnofsky scores. Age of the patients correlated negatively with two SF-36 dimensions (physical functioning and role limitation due to physical fitness) and Karnofsky scores. CONCLUSION: This study revealed a good correlation between

  2. Moving beyond Karnofsky and ECOG Performance Status Assessments with New Technologies

    PubMed Central

    Kelly, Ciara M.; Shahrokni, Armin

    2016-01-01

    Progress in cancer research is coupled with increased treatment complexity reliant upon accurate patient selection. Oncologists rely upon measurement instruments of functional performance such as the Karnofsky or Eastern Cooperative Oncology Group Performance Status scales that were developed over fifty years ago to determine a patient's suitability for systemic treatment. These standard assessment tools have been shown to correlate with response to chemotherapy, chemotherapy tolerability, survival, and quality of life of cancer patients. However, these scales are subjective, subject to bias and high interobserver variability. Despite these limitations important clinical decisions are based on PS including eligibility for clinical trials, the “optimal” therapeutic approach in routine practice, and the allocation of healthcare resources. This paper reviews the past, present, and potential future of functional performance status assessment in an oncology setting. The potential ability of electronic activity monitoring systems to provide an objective, accurate measurement of patient functional performance is explored. Electronic activity monitoring devices have the potential to offer positive health-related opportunities to patients; however their introduction to the healthcare setting is not without difficulty. The potential role of this technology in healthcare and the challenges that these new innovations pose to the healthcare industry are also examined. PMID:27066075

  3. Outcome After Radiosurgery for Brain Metastases in Patients With Low Karnofsky Performance Scale (KPS) Scores

    SciTech Connect

    Chernov, Mikhail F. |. E-mail: m_chernov@yahoo.com; Nakaya, Kotaro; Izawa, Masahiro; Usuba, Yuki; Kato, Koichi; Hori, Tomokatsu; Hayashi, Motohiro |; Muragaki, Yoshihiro |; Iseki, Hiroshi ||; Takakura, Kintomo ||

    2007-04-01

    Purpose: The objective of this retrospective study was evaluation of the outcome after stereotactic radiosurgery (SRS) in patients with intracranial metastases and poor performance status. Methods and Materials: Forty consecutive patients with metastatic brain tumors and Karnofsky performance scale (KPS) scores {<=}50 (mean, 43 {+-} 8; median, 40) treated with SRS were analyzed. Poor performance status was caused by presence of intracranial metastases in 28 cases (70%) and resulted from uncontrolled extracerebral disease in 12 (30%). Results: Survival after SRS varied from 3 days to 11.5 months (mean, 3.8 {+-} 2.9 months; median, 3.3 months). Survival probability constituted 0.50 {+-} 0.07 at 3 months and 0.20 {+-} 0.05 at 6 months posttreatment. Cause of low KPS score (p = 0.0173) and presence of distant metastases beside the brain (p = 0.0308) showed statistically significant associations with overall survival in multivariate Cox proportional hazards regression analysis. Median survival was 6.0 months if low KPS score was caused by cerebral disease and distant metastases in regions beyond the brain were absent, 3.3 months if low KPS score was caused by cerebral disease and distant metastases in regions beyond the brain were present, and 1.0 month if poor performance status resulted from extracerebral disease. Conclusions: Identification of the cause of low KPS score (cerebral vs. extracerebral) in patients with metastatic brain tumor(s) may be important for prediction of the outcome after radiosurgical treatment. If poor patient performance status without surgical indications is caused by intracranial tumor(s), SRS may be a reasonable treatment option.

  4. Karnofsky Performance Status and Lactate Dehydrogenase Predict the Benefit of Palliative Whole-Brain Irradiation in Patients With Advanced Intra- and Extracranial Metastases From Malignant Melanoma

    SciTech Connect

    Partl, Richard; Richtig, Erika; Avian, Alexander; Berghold, Andrea; Kapp, Karin S.

    2013-03-01

    Purpose: To determine prognostic factors that allow the selection of melanoma patients with advanced intra- and extracerebral metastatic disease for palliative whole-brain radiation therapy (WBRT) or best supportive care. Methods and Materials: This was a retrospective study of 87 patients who underwent palliative WBRT between 1988 and 2009 for progressive or multiple cerebral metastases at presentation. Uni- and multivariate analysis took into account the following patient- and tumor-associated factors: gender and age, Karnofsky performance status (KPS), neurologic symptoms, serum lactate dehydrogenase (LDH) level, number of intracranial metastases, previous resection or stereotactic radiosurgery of brain metastases, number of extracranial metastasis sites, and local recurrences as well as regional lymph node metastases at the time of WBRT. Results: In univariate analysis, KPS, LDH, number of intracranial metastases, and neurologic symptoms had a significant influence on overall survival. In multivariate survival analysis, KPS and LDH remained as significant prognostic factors, with hazard ratios of 3.3 (95% confidence interval [CI] 1.6-6.5) and 2.8 (95% CI 1.6-4.9), respectively. Patients with KPS ≥70 and LDH ≤240 U/L had a median survival of 191 days; patients with KPS ≥70 and LDH >240 U/L, 96 days; patients with KPS <70 and LDH ≤240 U/L, 47 days; and patients with KPS <70 and LDH >240 U/L, only 34 days. Conclusions: Karnofsky performance status and serum LDH values indicate whether patients with advanced intra- and extracranial tumor manifestations are candidates for palliative WBRT or best supportive care.

  5. Clinical studies of photodynamic therapy for malignant brain tumors: Karnofsky score and neurological score in patients with recurrent gloms treated with Photofrin PDT

    NASA Astrophysics Data System (ADS)

    Muller, Paul J.; Wilson, Brian C.; Lilge, Lothar D.; Yang, Victor X.; Varma, Abhay; Bogaards, Arjen; Hetzel, Fred W.; Chen, Qun; Fullagar, Tim; Fenstermaker, Robert; Selker, Robert; Abrams, Judith

    2002-06-01

    In our previous phase II studies we treated 112 patients with malignant brain tumors with 2-mg/kg Photofrin i.v. and intra-operative cavitary PDT. We concluded that PDT was safe in patients with newly diagnosed or recurrent supratentorial malignant gliomas. Pathology, performance grade and light dose were significantly related to survival time. In selected patients when an adequate light dose was used survival time improved. The surgical mortality rate was less than 3%. [spie 2000] We have initiated two randomized prospective trials - the first, to determine if the addition of PDT to standard therapy [surgery, radiation and/or chemotherapy] prolongs the survival of patients with newly diagnosed malignant astrocytic tumors; and the second, to determine whether high light dose PDT [120 J/cm2] is superior to low light dose PDT [40 J/cm2] in patients with recurrent malignant astrocytic tumors. To date, 158 patients have been recruited - 72 to the newly diagnosed malignant glioma study and 86 to the recurrent glioma study. In the recurrent glioma study we compared the pre-operative KS and elements of the neurological examination [speech function, visual fields, cognitive function, sensory examination and gait] to the post-operative examinations at hospital discharge. The means were compared by paired student-t test. The KS in 86 of 88 patients with recurrent gliomas were assessable. The mean [s.d.] preoperative and post-operative KS were 82+/- 14 and 79+/- 17, respectively [p=0.003]. The mean decline in KS, although statistically significant, was small and of no clinical importance. The median Karnofsky score changed from 90 to 80. The KS improved in 8 patients; their post-operative average length of stay (alos) was =9.7 days. There was no change in 47 [alos=8.3], a decline of 10 points in 24 [aloc=13.4] and declined by more than 10 points in 7 [alos=23.3]. Three of these 7 patients who had a decline of >10 points improved in follow-up but did not reach their

  6. Age-related changes in triathlon performances.

    PubMed

    Lepers, R; Sultana, F; Bernard, T; Hausswirth, C; Brisswalter, J

    2010-04-01

    The aim of this study was two-fold: i) to analyse age-related declines in swimming, cycling, and running performances for Olympic and Ironman triathlons, and ii) to compare age-related changes in these three disciplines between the Olympic and Ironman triathlons. Swimming, cycling, running and total time performances of the top 10 males between 20 and 70 years of age (in 5 years intervals) were analysed for two consecutive world championships (2006 and 2007) for Olympic and Ironman distances. There was a lesser age-related decline in cycling performance (p<0.01) compared with running and swimming after 55 years of age for Olympic distance and after 50 years of age for Ironman distance. With advancing age, the performance decline was less pronounced (p<0.01) for Olympic than for Ironman triathlon in cycling (>55 years) and running (>50 years), respectively. In contrast, an age-related decline in swimming performance seemed independent of triathlon distance. The age-related decline in triathlon performance is specific to the discipline, with cycling showing less declines in performance with age than swimming and running. The magnitude of the declines in cycling and running performance at Ironman distance is greater than at Olympic distance, suggesting that task duration exerts an important influence on the magnitude of the age-associated changes in triathlon performance.

  7. The Effects of Aging on Motor Performance.

    ERIC Educational Resources Information Center

    Kleinman, Matthew

    A review of research on the effects of aging on motor performance provided evidence that age-induced changes within the central nervous system, particularly in the functioning of the non-dominant cortical hemisphere, result in diminished fluid abilities. The loss was most clearly manifested behaviorally as a decreased capacity to perform…

  8. Unimanual Performance across the Age Span

    ERIC Educational Resources Information Center

    Bryden, P.J.; Roy, E.A.

    2005-01-01

    The purpose of the current investigation was to examine the age-related changes in the performance of the two hands on the Annett pegboard (Annett, 1970). The current study was part of a large-scale study investigating the development of unimanual and bimanual performance. Three hundred and two right-handed individuals participated in the present…

  9. Designing Performance Interventions for the Information Age

    ERIC Educational Resources Information Center

    Schatz, Steven; Schwen, Thomas M.

    2006-01-01

    Dynamic Online Performance Support Systems (DOPSS) are a new class of intervention that can meet the needs of a quickly changing work force in an information age environment. These systems are customized for the target population, with unique meta tags, unique function sets, and dynamic growth for and by users in use. These unique tag sets allow…

  10. Effects of age and gender on physical performance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our purpose was to assess the effects of age and gender on physical performance using one-hour swimming performance and participation in 2,173 man and 2,098 women, aged 19 – 91 years from a long distance (one-hour) national competition. Decline in performance with aging was found to be quadratic rat...

  11. A rise in peak performance age in female athletes.

    PubMed

    Elmenshawy, Ahmed R; Machin, Daniel R; Tanaka, Hirofumi

    2015-06-01

    It was reported in 1980s that ages at which peak performance was observed had remained remarkably stable in the past century, although absolute levels of athletic performance increased dramatically for the same time span. The emergence of older (masters) athletes in the past few decades has changed the demographics and age-spectrum of Olympic athletes. The primary aim of the present study was to determine whether the ages at which peak performance was observed had increased in the recent decades. The data spanning 114 years from the first Olympics (1898) to the most recent Olympics (2014) were collected using the publically available data. In the present study, ages at which Olympic medals (gold, silver, and bronze) were won were used as the indicators of peak performance age. Track and field, swimming, rowing, and ice skating events were analyzed. In men, peak performance age did not change significantly in most of the sporting events (except in 100 m sprint running). In contrast, peak performance ages in women have increased significantly since 1980s and consistently in all the athletic events examined. Interestingly, as women's peak performance age increased, they became similar to men's peak ages in many events. In the last 20-30 years, ages at which peak athletic performance is observed have increased in women but not in men.

  12. Relative Age Affects Marathon Performance in Male and Female Athletes

    PubMed Central

    Connick, Mark J.; Beckman, Emma M.; Tweedy, Sean M.

    2015-01-01

    Marathon runners are ranked in 5-year age groups. However the extent to which 5-year groupings facilitates equitable competition has not been evaluated. The aim of this study was to evaluate the effect of relative age in male and female marathon running. Marathon finishing times for the top ten male (aged 20-69 years) and female athletes (aged 20-64 years) were obtained from the 2013 New York and Chicago marathons. Intra-class and inter-class validity were evaluated by comparing performances within (intra-class) and between (inter-class) the 5-year age groups. Results showed intra-class effects in all male age groups over 50 years, in all female age groups over 40 years, and in male and female 20-24 age groups (p < 0.05). Inter-class differences existed between the 20-24 and 25-29 age groups in both males and females, between all male age groups over 50 years, and between all female age groups over 40 years (p < 0.05). This study provided the first evaluation of the effects of relative age in male and female marathon running. The results provide preliminary but compelling evidence that the relatively older male athletes in age groups over 50 years and the relatively older females in age groups over 40 years are competitively disadvantaged compared to the younger athletes in these age groups. Key points Results showed a curvilinear relationship between age and marathon running performance with the negative effect of age becoming more pronounced in older runners. Relative age effects were found in all age groups over age 50 years in males and over age 40 years in females indicating that the relatively older runners were competitively disadvantaged compared to the relatively younger runners in these age groups. Relative age affected the 20-24 age classification which is consistent with the hypothesis that marathon performance improves until peak performance occurs in the 25-29 age classification. PMID:26336355

  13. Relative Age Affects Marathon Performance in Male and Female Athletes.

    PubMed

    Connick, Mark J; Beckman, Emma M; Tweedy, Sean M

    2015-09-01

    Marathon runners are ranked in 5-year age groups. However the extent to which 5-year groupings facilitates equitable competition has not been evaluated. The aim of this study was to evaluate the effect of relative age in male and female marathon running. Marathon finishing times for the top ten male (aged 20-69 years) and female athletes (aged 20-64 years) were obtained from the 2013 New York and Chicago marathons. Intra-class and inter-class validity were evaluated by comparing performances within (intra-class) and between (inter-class) the 5-year age groups. Results showed intra-class effects in all male age groups over 50 years, in all female age groups over 40 years, and in male and female 20-24 age groups (p < 0.05). Inter-class differences existed between the 20-24 and 25-29 age groups in both males and females, between all male age groups over 50 years, and between all female age groups over 40 years (p < 0.05). This study provided the first evaluation of the effects of relative age in male and female marathon running. The results provide preliminary but compelling evidence that the relatively older male athletes in age groups over 50 years and the relatively older females in age groups over 40 years are competitively disadvantaged compared to the younger athletes in these age groups. Key pointsResults showed a curvilinear relationship between age and marathon running performance with the negative effect of age becoming more pronounced in older runners.Relative age effects were found in all age groups over age 50 years in males and over age 40 years in females indicating that the relatively older runners were competitively disadvantaged compared to the relatively younger runners in these age groups.Relative age affected the 20-24 age classification which is consistent with the hypothesis that marathon performance improves until peak performance occurs in the 25-29 age classification.

  14. Effects of Antihistamine, Age, And Gender on Task Performance

    DTIC Science & Technology

    1999-07-01

    This investigation was designed to study the effects of the antihistamine, chlorpheniramine maleate, as well as the influence of age and gender...singly and in combination with chlorpheniramine maleate, on selected types of performance tasks. It was hypothesized that chiorpheniramine maleate would... chlorpheniramine maleate on any dependent measure for any performance task. However, several interactions of age and gender with chlorpheniramine maleate

  15. Trends in Triathlon Performance: Effects of Sex and Age.

    PubMed

    Lepers, Romuald; Knechtle, Beat; Stapley, Paul J

    2013-09-01

    The influences of sex and age upon endurance performance have previously been documented for both running and swimming. A number of recent studies have investigated how sex and age influence triathlon performance, a sport that combines three disciplines (swimming, cycling and running), with competitions commonly lasting between 2 (short distance: 1.5-km swim, 40-km cycle and 10-km run) and 8 h (Ironman distance: 3.8-km swim,180-km cycle and 42-km run) for elite triathletes. Age and sex influences upon performance have also been investigated for ultra-triathlons, with distances corresponding to several Ironman distances and lasting several days, and for off-road triathlons combining swimming, mountain biking and trail running. Triathlon represents an intriguing alternative model for analysing the effects of age and sex upon endurance and ultra-endurance ([6 h) performance because sex differences and age-related declines in performance can be analysed in the same individuals across the three separate disciplines. The relative participation of both females and masters athletes (age[40 years) in triathlon has increased consistently over the past 25 years. Sex differences in triathlon performance are also known to differ between the modes of locomotion adopted (swimming, cycling or running) for both elite and non-elite triathletes. Generally, time differences between sexes in swimming have been shown to be smaller on average than during cycling and running. Both physiological and morphological factors contribute to explaining these findings. Performance density (i.e. the time difference between the winner and tenth-placed competitor) has progressively improved (time differences have decreased) for international races over the past two decades for both males and females, with performance density now very similar for both sexes. For age-group triathletes, sex differences in total triathlon performance time increases with age. However,the possible difference in age

  16. Formulation of the Age-Education Index: Measuring Age and Education Effects in Neuropsychological Performance

    ERIC Educational Resources Information Center

    Lam, Max; Eng, Goi Khia; Rapisarda, Attilio; Subramaniam, Mythily; Kraus, Michael; Keefe, Richard S. E.; Collinson, Simon Lowes

    2013-01-01

    The complex interplay of education, age, and cognitive performance on various neuropsychological tests is examined in the current study. New education indices were formulated and further investigated to reveal how age and education variances work together to account for performance on neuropsychological tests. Participants were 830…

  17. Peak athletic performance and ageing: evidence from baseball.

    PubMed

    Bradbury, John Charles

    2009-04-01

    Baseball players exhibit a pattern of improvement and decline in performance; however, differing lengths of careers and changes in rules and characteristics of the game complicate assessments of age-related effects on performance. This study attempts to isolate the impact of age on several player skills while controlling for relevant outside factors using longitudinal data from 86 seasons of Major League Baseball. The results indicate that players age in different skills in accord with studies of ageing in other athletic contests. For overall performance, multiple-regression estimates indicate that hitters and pitchers peak around the age of 29 - later than previous estimates. Athletic skills such as hitting and running peak earlier than skills that rely heavily on experience and knowledge, such as issuing and drawing walks.

  18. Changes in Track and Field Performance with Chronological Aging.

    ERIC Educational Resources Information Center

    Fung, Lena; Ha, Amy

    1994-01-01

    Examined official records of VIII World Veterans Championships to identify running, jumping, and throwing events whose performance was most affected by age. Found that 400-meter run and long jump were most affected by advancing age among both male and female master athletes whereas, in areas of throws, event most affected was javelin for men and…

  19. Age and practice effects on inter-manual performance asymmetry.

    PubMed

    Francis, Karen L; MacRae, Priscilla G; Spirduso, Waneen W; Eakin, Tim

    2014-01-01

    Manual dexterity declines with increasing age, however, the way in which inter-manual asymmetry responds to aging is unclear. Our purpose was to determine the effect of age and practice on inter-manual performance asymmetry in an isometric force pinch line tracing task that varied in difficulty within segments. Thirty right-handed participants, five males and five females in each of three age groups, young (Y20), young-old (O70), and old-old (O80), practiced an isometric force pinch task for 10 trials with each hand on each of five consecutive days. Inter-manual performance asymmetry of the right and left hands was analyzed with a repeated measures analysis of variance (ANOVA) of asymmetry with age groups, practice, task difficulty, and hand as factors. The within-individual magnitude of asymmetry was also analyzed with a repeated measures ANOVA of manual asymmetry calculated as an asymmetry index (AI). Post hoc pair-wise comparisons were performed when significance was found. We observed no inter-manual performance asymmetry on this isometric tracing task among any of the age groups, either in the hand performance differences or in the magnitude of the AI. Age and practice interacted in terms of manual performance: the Y20 and O70 group improved accuracy and task time across the 5 days of practice but the O80 group did not. However, practice did not differentially affect the AI for accuracy or task time for any group. Accuracy of performance of the two hands was differentially affected by practice. All age groups exhibited poorer performance and larger AIs on the most difficult segments of the task (3 and 6) and this did not change with practice.

  20. Age, psychological skills, and golf performance: a prospective investigation.

    PubMed

    Hayslip, Bert; Petrie, Trent A

    2014-03-01

    This study explored the influence of age in understanding mental skills utilization in the context of performance at a major national golf competition. Participants, who ranged in age and in skill level, included 1150 male and 170 female amateur golfers competing in the Dupont World Amateur Golf Championship in Myrtle Beach, South Carolina. Measures targeted general mental skills used in competitions, golf-specific skills, and competitive trait anxiety. Hierarchical linear regression was utilized to explore the potential moderating role that chronological age may play in influencing the impact of psychological skills and anxiety on competitive tournament performance across the adult life span. Findings suggested no significant age-moderating effects and instead pointed to the importance of developing golf-specific psychological skills to enhance or maintain performance, irrespective of age. Although automaticity (performance feels "automatic") predicted performance for all golfers, commitment to the game and confidence in one's putting did so only for the men. These findings reinforce the age-irrelevant role of such skills in fostering the experience of peak performance in a competitive sport context and underscore the importance of interventions targeting older players to help maintain or facilitate the use of psychological skills in helping them manage their games.

  1. Age-related changes in ultra-triathlon performances

    PubMed Central

    2012-01-01

    Background The age-related decline in performance has been investigated in swimmers, runners and triathletes. No study has investigated the age-related performance decline in ultra-triathletes. The purpose of this study was to analyse the age-related declines in swimming, cycling, running and overall race time for both Triple Iron ultra-triathlon (11.4-km swimming, 540-km cycling and 126.6-km running) and Deca Iron ultra-triathlon (38-km swimming, 1,800-km cycling and 420-km running). Methods The age and performances of 423 male Triple Iron ultra-triathletes and 119 male Deca Iron ultra-triathletes were analysed from 1992 to 2010 using regression analyses and ANOVA. Results The mean age of the finishers was significantly higher for Deca Iron ultra-triathletes (41.3 ± 3.1 years) compared to a Triple Iron ultra-triathletes (38.5 ± 3.3 years) (P < 0.05). For both ultra-distances, the fastest overall race times were achieved between the ages of 25 and 44 years. Deca Iron ultra-triathletes achieved the same level of performance in swimming and cycling between 25 and 54 years of age. Conclusions The magnitudes of age-related declines in performance in the three disciplines of ultra-triathlon differ slightly between Triple and Deca Iron ultra-triathlon. Although the ages of Triple Iron ultra-triathletes were on average younger compared to Deca Iron ultra-triathletes, the fastest race times were achieved between 25 and 44 years for both distances. Further studies should investigate the motivation and training of ultra-triathletes to gain better insights in ultra-triathlon performance. PMID:23849327

  2. Age and gender interactions in short distance triathlon performance.

    PubMed

    Etter, Franziska; Knechtle, Beat; Bukowski, Arkadiusz; Rüst, Christoph Alexander; Rosemann, Thomas; Lepers, Romuald

    2013-01-01

    This study investigated the participation and performance trends as well as the age and gender interaction at the Olympic distance 'Zürich Triathlon' (1.5 km swim, 40 km cycle and 10 km run) from 2000 to 2010 in 7,939 total finishers (1,666 females and 6,273 males). Female triathletes aged from 40 to 54 years significantly (P < 0.05) increased their participation while the participation of younger females and males remained stable. Males of 50-54 years of age and females of 45-49 years of age improved their total race time. For elite top five overall triathletes, mean gender differences in swimming, cycling, running and overall race time were 15.2 ± 4.6%, 13.4 ± 2.3%, 17.1 ± 2.5%, and 14.8 ± 1.8%, respectively. For both elite and age group athletes, the gender difference in cycling time was significantly (P <0.001) lower than for swimming and running. The gender difference in overall Olympic distance triathlon performance increased after the age of 35 years, which appeared earlier compared to long distance triathlon as suggested by previous studies. Future investigations should compare gender difference in performance for different endurance events across age to confirm a possible effect of exercise duration on gender difference with advancing age.

  3. Age-Dependent Face Detection and Face Categorization Performance

    PubMed Central

    Carbon, Claus-Christian; Grüter, Martina; Grüter, Thomas

    2013-01-01

    Empirical studies on the development of face processing skills with age show inconsistent patterns concerning qualitative vs. quantitative changes over time or the age range for peak cognitive performance. In the present study, we tested the proficiency in face detection and face categorization with a large sample of participants (N = 312; age range: 2-88 yrs). As test objects, we used so-called Mooney faces, two-tone (black and white) images of faces lacking critical information of a local, featural and relational nature, reflecting difficult real world face processing conditions. We found that performance in the assessment of gender and age from Mooney faces increases up to about age 15, and decreases from 65 years on. The implications of these findings are discussed in the light of classic and recent findings from face development literature. PMID:24116236

  4. The effect of age on cognitive performance of frontal patients

    PubMed Central

    Cipolotti, Lisa; Healy, Colm; Chan, Edgar; MacPherson, Sarah E.; White, Mark; Woollett, Katherine; Turner, Martha; Robinson, Gail; Spanò, Barbara; Bozzali, Marco; Shallice, Tim

    2015-01-01

    Age is known to affect prefrontal brain structure and executive functioning in healthy older adults, patients with neurodegenerative conditions and TBI. Yet, no studies appear to have systematically investigated the effect of age on cognitive performance in patients with focal lesions. We investigated the effect of age on the cognitive performance of a large sample of tumour and stroke patients with focal unilateral, frontal (n=68), or non-frontal lesions (n=45) and healthy controls (n=52). We retrospectively reviewed their cross sectional cognitive and imaging data. In our frontal patients, age significantly predicted the magnitude of their impairment on two executive tests (Raven's Advanced Progressive Matrices, RAPM and the Stroop test) but not on nominal (Graded Naming Test, GNT) or perceptual (Incomplete Letters) task. In our non-frontal patients, age did not predict the magnitude of their impairment on the RAPM and GNT. Furthermore, the exacerbated executive impairment observed in our frontal patients manifested itself from middle age. We found that only age consistently predicted the exacerbated executive impairment. Lesions to specific frontal areas, or an increase in global brain atrophy or white matter abnormalities were not associated with this impairment. Our results are in line with the notion that the frontal cortex plays a critical role in aging to counteract cognitive and neuronal decline. We suggest that the combined effect of aging and frontal lesions impairs the frontal cortical systems by causing its computational power to fall below the threshold needed to complete executive tasks successfully. PMID:26102190

  5. Diet-induced ketosis improves cognitive performance in aged rats.

    PubMed

    Xu, Kui; Sun, Xiaoyan; Eroku, Bernadette O; Tsipis, Constantinos P; Puchowicz, Michelle A; LaManna, Joseph C

    2010-01-01

    Aging is associated with increased susceptibility to hypoxic/ischemic insult and declines in behavioral function which may be due to attenuated adaptive/defense responses. We investigated if diet-induced ketosis would improve behavioral performance in the aged rats. Fischer 344 rats (3- and 22-month-old) were fed standard (STD) or ketogenic (KG) diet for 3 weeks and then exposed to hypobaric hypoxia. Cognitive function was measured using the T-maze and object recognition tests. Motor function was measured using the inclined-screen test. Results showed that KG diet significantly increased blood ketone levels in both young and old rats. In the aged rats, the KG diet improved cognitive performance under normoxic and hypoxic conditions; while motor performance remained unchanged. Capillary density and HIF-1alpha levels were elevated in the aged ketotic group independent of hypoxic challenge. These data suggest that diet-induced ketosis may be beneficial in the treatment of neurodegenerative conditions.

  6. Motor Performance is Impaired Following Vestibular Stimulation in Ageing Mice

    PubMed Central

    Tung, Victoria W. K.; Burton, Thomas J.; Quail, Stephanie L.; Mathews, Miranda A.; Camp, Aaron J.

    2016-01-01

    Balance and maintaining postural equilibrium are important during stationary and dynamic movements to prevent falls, particularly in older adults. While our sense of balance is influenced by vestibular, proprioceptive, and visual information, this study focuses primarily on the vestibular component and its age-related effects on balance. C57Bl/6J mice of ages 1, 5–6, 8–9 and 27–28 months were tested using a combination of standard (such as grip strength and rotarod) and newly-developed behavioral tests (including balance beam and walking trajectory tests with a vestibular stimulus). In the current study, we confirm a decline in fore-limb grip strength and gross motor coordination as age increases. We also show that a vestibular stimulus of low frequency (2–3 Hz) and duration can lead to age-dependent changes in balance beam performance, which was evident by increases in latency to begin walking on the beam as well as the number of times hind-feet slip (FS) from the beam. Furthermore, aged mice (27–28 months) that received continuous access to a running wheel for 4 weeks did not improve when retested. Mice of ages 1, 10, 13 and 27–28 months were also tested for changes in walking trajectory as a result of the vestibular stimulus. While no linear relationship was observed between the changes in trajectory and age, 1-month-old mice were considerably less affected than mice of ages 10, 13 and 27–28 months. Conclusion: this study confirms there are age-related declines in grip strength and gross motor coordination. We also demonstrate age-dependent changes to finer motor abilities as a result of a low frequency and duration vestibular stimulus. These changes showed that while the ability to perform the balance beam task remained intact across all ages tested, behavioral changes in task performance were observed. PMID:26869921

  7. Aging Behavior and Performance Projections for a Polysulfide Elastomer

    SciTech Connect

    Celina, Mathias C.; Giron, Nicholas Henry; Quintana, Adam

    2015-05-01

    The accelerated aging behavior and aging state of a 30 year old field retrieved polysulfide elastomer was examined. The material is used as an environmental thread sealant for a stainless steel bolt in a steel threaded insert in an aluminum assembly. It is a two component curable polysulfide elastomer that is commercially available in a similar formulation as was applied 30 years ago. The primary goal of this study was to establish if aging over 30 years under moderate aging conditions (mostly ambient temperature and humidity) resulted in significant property changes, or if accelerated aging could identify developing aging pathways which would prevent the extended use of this material. The aging behavior of this material was examined in three ways: A traditional accelerated thermo-oxidative aging study between 95 to 140°C which focused on physical and chemical properties changes, an evaluation of the underlying oxidation rates between RT and 125°C, and an assessment of the aging state of a small 30 year old sample. All three data sets were used to establish aging characteristics, their time evolution, and to extrapolate the observed behavior to predict performance limits at RT. The accelerated aging study revealed a relatively high average activation energy of ~130 kJ/mol which gives overconfident performance predictions. Oxidation rates showed a decreasing behavior with aging time and a lower E a of ~84 kJ/mol from time - temperature superposition , but also predicted sufficient additional performance at RT. Consistent with these projections for extended RT performance, only small changes were observed for the 30 year old material. Extrapolations using this partially aged material also predict ongoing use as a viable option. Unexpected RT degradation could only develop into a concern should the oxidation rate not trend lower over time as was observed at elevated temperature. Considering all data acquired in this limited aging study , there are no immediately

  8. Age and diagnostic performance of Alzheimer disease CSF biomarkers

    PubMed Central

    Rosén, E.; Hansson, O.; Andreasen, N.; Parnetti, L.; Jonsson, M.; Herukka, S.-K.; van der Flier, W.M.; Blankenstein, M.A.; Ewers, M.; Rich, K.; Kaiser, E.; Verbeek, M.M.; Olde Rikkert, M.; Tsolaki, M.; Mulugeta, E.; Aarsland, D.; Visser, P.J.; Schröder, J.; Marcusson, J.; de Leon, M.; Hampel, H.; Scheltens, P.; Wallin, A.; Eriksdotter-Jönhagen, M.; Minthon, L.; Winblad, B.; Blennow, K.; Zetterberg, H.

    2012-01-01

    Objectives: Core CSF changes in Alzheimer disease (AD) are decreased amyloid β1–42, increased total tau, and increased phospho-tau, probably indicating amyloid plaque accumulation, axonal degeneration, and tangle pathology, respectively. These biomarkers identify AD already at the predementia stage, but their diagnostic performance might be affected by age-dependent increase of AD-type brain pathology in cognitively unaffected elderly. Methods: We investigated effects of age on the diagnostic performance of CSF biomarkers in a uniquely large multicenter study population, including a cross-sectional cohort of 529 patients with AD dementia (median age 71, range 43–89 years) and 304 controls (67, 44–91 years), and a longitudinal cohort of 750 subjects without dementia with mild cognitive impairment (69, 43–89 years) followed for at least 2 years, or until dementia diagnosis. Results: The specificities for subjects without AD and the areas under the receiver operating characteristics curves decreased with age. However, the positive predictive value for a combination of biomarkers remained stable, while the negative predictive value decreased only slightly in old subjects, as an effect of the high AD prevalence in older ages. Conclusion: Although the diagnostic accuracies for AD decreased with age, the predictive values for a combination of biomarkers remained essentially stable. The findings highlight biomarker variability across ages, but support the use of CSF biomarkers for AD even in older populations. PMID:22302554

  9. Fetal Habituation Performance: Gestational Age and Sex Effects

    ERIC Educational Resources Information Center

    McCorry, Noleen K.; Hepper, Peter G.

    2007-01-01

    Habituation is the decrement in response to repeated stimulation. Fetal habituation performance may reflect the functioning of the central nervous system (CNS) prenatally. However, basic characteristics of the prenatal habituation phenomena remain unclear, such as the relationship with gestational age (GA) and fetal sex. The current study…

  10. Formulation of the age-education index: measuring age and education effects in neuropsychological performance.

    PubMed

    Lam, Max; Eng, Goi Khia; Rapisarda, Attilio; Subramaniam, Mythily; Kraus, Michael; Keefe, Richard S E; Collinson, Simon Lowes

    2013-03-01

    The complex interplay of education, age, and cognitive performance on various neuropsychological tests is examined in the current study. New education indices were formulated and further investigated to reveal how age and education variances work together to account for performance on neuropsychological tests. Participants were 830 English-speaking ethnic Chinese. Neuropsychological measures such as Verbal Memory, Digit Sequencing, Token Motor Task, Semantic Fluency, Symbol Coding, Tower of London, Judgment of Line Orientation, and Matrix Reasoning of the Wechsler Adult Intelligence Scale were administered. Education was measured by total years of education and adjusted years of education, as well as ratios of both measures with age. Age and education were associated with neuropsychological performance. Adjusted years of education was associated with fluency and higher cognitive processes, while the ratio between adjusted years of education and age was associated with tasks implicating working memory. Changes in education modalities implicated tasks requiring language abilities. Education and age represent key neurodevelopmental milestones. In light of our findings, special consideration should to be given when neuropsychological assessments are carried out in cross-cultural contexts and in societies where educational systems and pedagogy tend to be complex.

  11. Age differences in simulated driving performance: compensatory processes.

    PubMed

    Andrews, E C; Westerman, S J

    2012-03-01

    In the context of driving, the reported experiment examines compensatory processes for age-related declines in cognitive ability. Younger (26-40 years) and older (60+ years) participants (n=22 each group) performed a car following task in a driving simulator. Several performance measures were recorded, including assessments of anticipation of unfolding traffic events. Participants also completed a range of measures of cognitive ability - including both fluid and crystallised abilities. Three examples of age-related compensation are reported: (i) older drivers adopted longer headways than younger drivers. Data were consistent with this being compensation for an age-related deficit in complex reaction time; (ii) older drivers with relatively higher cognitive ability anticipated traffic events more frequently, whereas the reverse pattern was found for younger drivers; and, (iii) older drivers with greater crystallised ability were less reliant on spatial ability to maintain lane position. Consistent with theories of 'cognitive reserve', interactions between crystallised ability and age for self-report workload suggested that compensation for age-related cognitive ability deficits required investment of additional effort. Results are considered in the context of the prospects of further assessment of older drivers.

  12. Moon Age and Regolith Explorer (MARE) Mission Design and Performance

    NASA Technical Reports Server (NTRS)

    Condon, Gerald L.; Lee, David E.; Carson, John M., III

    2017-01-01

    On December 11, 1972, Apollo 17 marked the last controlled U.S. lunar landing and was followed by an absence of methodical in-situ investigation of the lunar surface. The Moon Age and Regolith Explorer (MARE) proposal provides scientific measurement of the age and composition of a relatively young portion of the lunar surface near Aristarchus Plateau and the first post-Apollo U.S. soft lunar landing. It includes the first demonstration of a crew survivability-enhancing autonomous hazard detection and avoidance system. This report focuses on the mission design and performance associated with the MARE robotic lunar landing subject to mission and trajectory constraints.

  13. Age and task parameters in continuous performance tests for preschoolers.

    PubMed

    Hagelthorn, Kathleen M; Hiemenz, Jennifer R; Pillion, Joseph P; Mahone, E Mark

    2003-06-01

    66 children (M=56.2 mo., SD=10.9), recruited from preschool and daycare centers, were administered two continuous performance tests, one auditory and one visual. Both tests utilized a format with one target and one nontarget. Interstimulus interval was fixed at 1350 msec. for the visual test and 5000 msec. for the auditory test. The visual test produced greater rates of omission and commission errors than the auditory test. Age was significantly related to mean reaction time and response variability for both tests; however, the visual test produced an unexpected pattern of increasing response time across age groups. On both tests omission rates improved significantly with age, while commission rates were consistent across ages 3-6 years. When considering continuous performance test paradigms for preschoolers, 3-yr.-olds may need at least a 4000-msec. interstimulus interval to make a choice for the stimulus cue. Hits following an interstimulus interval shorter than 1400 msec. may reflect younger preschoolers' response to a previous stimulus.

  14. Hair cortisol and cognitive performance in working age adults.

    PubMed

    McLennan, Skye N; Ihle, Andreas; Steudte-Schmiedgen, Susann; Kirschbaum, Clemens; Kliegel, Matthias

    2016-05-01

    It has been hypothesized that prolonged exposure to high cortisol levels results in cognitive impairment. However, previous research into the relationship between cortisol and cognition has produced mixed results, most likely due to difficulties achieving valid estimates of long-term cortisol exposure based on salivary or plasma cortisol assessments at a single time point. Furthermore, there has been little research on the cognitive effects of long-term cortisol exposure in working-age adults. In the present study, hair samples were collected from 246 nurses (89.8% female) aged from 21 to 62 (M=42.0, SD=11.2). Hair cortisol concentrations (HCC) in the proximal 3-cm hair segment were analyzed providing an estimate of integrated cortisol secretion over the 3 month-period prior to hair sampling. Cognition was measured using a battery of 15 neuropsychological tests, measuring core dimensions of memory, inductive reasoning, processing speed, crystalized intelligence and major aspects of executive functioning. HCC was not significantly related to any of the cognitive abilities measured, either before or after controlling for potential moderators such as age, sex, education, health, well-being, work ability and burnout. Tests for nonlinear relationships also yielded non-significant results. Thus, despite the study being well powered, long term cortisol exposure did not appear to be related to cognitive performance in this sample of working-age adults, suggesting that long term cortisol exposure may be less relevant to cognition in younger and middle-aged adults than was previously thought.

  15. The Relative Age Effect and Its Influence on Academic Performance

    PubMed Central

    Navarro, Juan-José; García-Rubio, Javier; Olivares, Pedro R.

    2015-01-01

    Introduction and Purpose The policy of school organisation for grouping students in the same academic year is based on date of birth. The differences in the experiences and maturation of older students involve a relatively better performance in academic settings, which is known as the relative age effect (RAE). This effect is more important the younger the student is. The goal of this study is to identify the connections of influence that RAE, socioeconomic status (SES), and type of institution have on academic performance in a school population of eighth graders. Methods The study is based on a population-based, representative sample of 15,234 8th graders (50.4% female; average age = 13.61 years) in the 2011 National System of Quality Assessment in Education Survey (SIMCE) from Chile. The SIMCE for global academic performance consists of 4 tests: reading, mathematics, social studies, and science. All tests consist of multiple-choice and closed questions. In addition, in order to have the information of general academic performance, an extra variable expressing the average score of each student was created. Also, the SIMCE includes additional variables for the evaluation process such as SES or type of school. Students were assigned to one of five age groups in terms of date of birth (G1, G2, G3, G4, and G5), in which students belonging to G1 are the oldest and students belonging to G5 are the youngest. Results The results achieved in the structural equation modelling indicate a good global fit. Individual relationships show significant effects of the three variables observed on academic performance, although SES received the highest values. The influence of RAE took place both in the full sample and sub-samples composed according to the SES and academic performance, showing higher values for students with lower scores. Although the influence of RAE decreases when SES is controlled, its effect is still significant and contributes to additionally explain the

  16. Moon Age and Regolith Explorer (MARE) Mission Design and Performance

    NASA Technical Reports Server (NTRS)

    Condon, Gerald L.; Lee, David E.

    2016-01-01

    The moon’s surface last saw a controlled landing from a U.S. spacecraft on December 11, 1972 with Apollo 17. Since that time, there has been an absence of methodical in-situ investigation of the lunar surface. In addition to the scientific value of measuring the age and composition of a relatively young portion of the lunar surface near Aristarchus Plateau, the Moon Age and Regolith Explorer (MARE) proposal provides the first U.S. soft lunar landing since the Apollo Program and the first ever robotic soft lunar landing employing an autonomous hazard detection and avoidance system, a system that promises to enhance crew safety and survivability during a manned lunar (or other) landing. This report focuses on the mission design and performance associated with the MARE robotic lunar landing subject to mission and trajectory constraints.

  17. An evaluation of sex-age-kill (SAK) model performance

    USGS Publications Warehouse

    Millspaugh, Joshua J.; Skalski, John R.; Townsend, Richard L.; Diefenbach, Duane R.; Boyce, Mark S.; Hansen, Lonnie P.; Kammermeyer, Kent

    2009-01-01

    The sex-age-kill (SAK) model is widely used to estimate abundance of harvested large mammals, including white-tailed deer (Odocoileus virginianus). Despite a long history of use, few formal evaluations of SAK performance exist. We investigated how violations of the stable age distribution and stationary population assumption, changes to male or female harvest, stochastic effects (i.e., random fluctuations in recruitment and survival), and sampling efforts influenced SAK estimation. When the simulated population had a stable age distribution and λ > 1, the SAK model underestimated abundance. Conversely, when λ < 1, the SAK overestimated abundance. When changes to male harvest were introduced, SAK estimates were opposite the true population trend. In contrast, SAK estimates were robust to changes in female harvest rates. Stochastic effects caused SAK estimates to fluctuate about their equilibrium abundance, but the effect dampened as the size of the surveyed population increased. When we considered both stochastic effects and sampling error at a deer management unit scale the resultant abundance estimates were within ±121.9% of the true population level 95% of the time. These combined results demonstrate extreme sensitivity to model violations and scale of analysis. Without changes to model formulation, the SAK model will be biased when λ ≠ 1. Furthermore, any factor that alters the male harvest rate, such as changes to regulations or changes in hunter attitudes, will bias population estimates. Sex-age-kill estimates may be precise at large spatial scales, such as the state level, but less so at the individual management unit level. Alternative models, such as statistical age-at-harvest models, which require similar data types, might allow for more robust, broad-scale demographic assessments.

  18. AGING PERFORMANCE OF MODEL 9975 PACKAGE FLUOROELASTOMER O-RINGS

    SciTech Connect

    Hoffman, E.; Daugherty, W.; Skidmore, E.; Dunn, K.; Fisher, D.

    2011-05-31

    The influence of temperature and radiation on Viton{reg_sign} GLT and GLT-S fluoroelastomer O-rings is an ongoing research focus at the Savannah River National Laboratory. The O-rings are credited for leaktight containment in the Model 9975 shipping package used for transportation of plutonium-bearing materials. At the Savannah River Site, the Model 9975 packages are being used for interim storage. Primary research efforts have focused on surveillance of O-rings from actual packages, leak testing of seals at bounding aging conditions and the effect of aging temperature on compression stress relaxation behavior, with the goal of service life prediction for long-term storage conditions. Recently, an additional effort to evaluate the effect of aging temperature on the oxidation of the materials has begun. Degradation in the mechanical properties of elastomers is directly related to the oxidation of the polymer. Sensitive measurements of the oxidation rate can be performed in a more timely manner than waiting for a measurable change in mechanical properties, especially at service temperatures. Measuring the oxidation rate therefore provides a means to validate the assumption that the degradation mechanisms(s) do not change from the elevated temperatures used for accelerated aging and the lower service temperatures. Monitoring the amount of oxygen uptake by the material over time at various temperatures can provide increased confidence in lifetime predictions. Preliminary oxygen consumption analysis of a Viton GLT-based fluoroelastomer compound (Parker V0835-75) using an Oxzilla II differential oxygen analyzer in the temperature range of 40-120 C was performed. Early data suggests oxygen consumption rates may level off within the first 100,000 hours (10-12 years) at 40 C and that sharp changes in the degradation mechanism (stress-relaxation) are not expected over the temperature range examined. This is consistent with the known long-term heat aging resistance of

  19. Performance of bolted closure joint elastomers under cask aging conditions

    SciTech Connect

    Verst, C.; Sindelar, R.; Skidmore, E.; Daugherty, W.

    2015-07-23

    The bolted closure joint of a bare spent fuel cask is susceptible to age-related degradation and potential loss of confinement function under long-term storage conditions. Elastomeric seals, a component of the joint typically used to facilitate leak testing of the primary seal that includes the metallic seal and bolting, is susceptible to degradation over time by several mechanisms, principally via thermo-oxidation, stress-relaxation, and radiolytic degradation under time and temperature condition. Irradiation and thermal exposure testing and evaluation of an ethylene-propylene diene monomer (EPDM) elastomeric seal material similar to that used in the CASTOR® V/21 cask for a matrix of temperature and radiation exposure conditions relevant to the cask extended storage conditions, and development of semiempirical predictive models for loss of sealing force is in progress. A special insert was developed to allow Compressive Stress Relaxation (CSR) measurements before and after the irradiation and/or thermal exposure without unloading the elastomer. A condition of the loss of sealing force for the onset of leakage was suggested. The experimentation and modeling being performed could enable acquisition of extensive coupled aging data as well as an estimation of the timeframe when loss of sealing function under aging (temperature/radiation) conditions may occur.

  20. Preliminary Transportation, Aging and Disposal Canister System Performance Specification

    SciTech Connect

    C.A Kouts

    2006-11-22

    This document provides specifications for selected system components of the Transportation, Aging and Disposal (TAD) canister-based system. A list of system specified components and ancillary components are included in Section 1.2. The TAD canister, in conjunction with specialized overpacks will accomplish a number of functions in the management and disposal of spent nuclear fuel. Some of these functions will be accomplished at purchaser sites where commercial spent nuclear fuel (CSNF) is stored, and some will be performed within the Office of Civilian Radioactive Waste Management (OCRWM) transportation and disposal system. This document contains only those requirements unique to applications within Department of Energy's (DOE's) system. DOE recognizes that TAD canisters may have to perform similar functions at purchaser sites. Requirements to meet reactor functions, such as on-site dry storage, handling, and loading for transportation, are expected to be similar to commercially available canister-based systems. This document is intended to be referenced in the license application for the Monitored Geologic Repository (MGR). As such, the requirements cited herein are needed for TAD system use in OCRWM's disposal system. This document contains specifications for the TAD canister, transportation overpack and aging overpack. The remaining components and equipment that are unique to the OCRWM system or for similar purchaser applications will be supplied by others.

  1. Resolution of mitochondrial oxidant stress improves aged-cardiovascular performance

    PubMed Central

    Owada, Takashi; Yamauchi, Hiroyuki; Miura, Shunsuke; Machii, Hirofumi; Takeishi, Yasuchika

    2017-01-01

    Background Senescence is a major factor that increases oxidative stress in mitochondria, which contributes toward the pathogenesis of heart disease. However, the effect of antioxidant therapy on cardiac mitochondria in aged-cardiac performance remains elusive. Objectives We postulated that the mitochondrial targeting of superoxide scavenging would have benefits in the aged heart. Methods and results Generation of superoxide in the mitochondria and nicotinamide adenine dinucleotide phosphate oxidase activity increased in the heart of old mice compared with that in young mice. In old mice treated with a mitochondria-targeted antioxidant MitoTEMPO (180 µg/kg/day, 28 days) co-infusion using a subcutaneously implanted minipump, levels of superoxide in the mitochondria and nicotinamide adenine dinucleotide phosphate oxidase activity as well as hydrogen peroxide decreased markedly in cardiomyocytes. Treatment with MitoTEMPO in old mice improved the systolic and diastolic function assessed by echocardiography. Endothelium-dependent vasodilation in isolated coronary arteries and endothelial nitric-oxide synthase phosphorylation were impaired in old mice compared with that in young mice and were improved by MitoTEMPO treatment. Mitochondria from the old mice myocardium showed lower rates of complex I-dependent and II-dependent respiration compared with that from young mice. Supplementation of MitoTEMPO in old mice improved the respiration rates and efficiency of ATP generation in mitochondria to a level similar to that of young mice. Conclusion Resolution of oxidative stress in mitochondria by MitoTEMPO in old mice restored cardiac function and the capacity of coronary vasodilation to the same magnitude observed in young mice. An antioxidant strategy targeting mitochondria could have a therapeutic benefit in heart disease with senescence. PMID:27740971

  2. Relationships between Personnel Tests, Age, and Job Performance.

    ERIC Educational Resources Information Center

    Arthur, Winfred, Jr.; Fuentes, Rick

    The age decrement model has traditionally been a fairly popular model of the human life span. This model has the basic premise that with increasing age there is a corresponding decrease in a wide range of abilities. Not all research has agreed with the unqualified age decrement model. This study examined the relationship between an…

  3. Language Performance and Reading Ability at 8 Years of Age.

    ERIC Educational Resources Information Center

    Morice, Rodney; Slaghuis, Walter

    1985-01-01

    Reports results from a detailed syntactic analysis of spoken language samples collected from poor and good readers at eight years of age. Results showed an undeniably strong association between reduced language comprehension and reading impairment at age eight, an association that appeared to strengthen by age nine. (SED)

  4. Age-related decline in olympic triathlon performance: effect of locomotion mode.

    PubMed

    Bernard, Thierry; Sultana, Frédéric; Lepers, Romuald; Hausswirth, Christophe; Brisswalter, Jeanick

    2010-01-01

    This study describes the decline in performance with age during Olympic triathlon Age Groups World Championships among the different locomotion modes. Mean performance of top 10 performers were analyzed for each group of age using the exponential model proposed by Baker, Tang, and Turner (2003, Experimental Aging Research, 29, 47-65). Comparison in performance decline was done between locomotion modes. Decline in performance in triathlon as a function of age follows an exponential model. A significant interaction effect between age and locomotion mode was observed on performance values. In swimming, a significant decrease was observed close to 5% per year after 45 years. Decline in performance was less pronounced in cycling until 60 years. Analysis of the effect of age in the different locomotion modes of a triathlon could provide information for maintaining quality of life with aging.

  5. Changes in Memory Prediction Accuracy: Age and Performance Effects

    ERIC Educational Resources Information Center

    Pearman, Ann; Trujillo, Amanda

    2013-01-01

    Memory performance predictions are subjective estimates of possible memory task performance. The purpose of this study was to examine possible factors related to changes in word list performance predictions made by younger and older adults. Factors included memory self-efficacy, actual performance, and perceptions of performance. The current study…

  6. Prenatal Marijuana Exposure and Intelligence Test Performance at Age 6

    ERIC Educational Resources Information Center

    Goldschmidt, Lidush; Richardson, Gale A.; Willford, Jennifer; Day, Nancy L.

    2008-01-01

    A study was conducted on lower income population women who were moderate users of marijuana to examine the effects of prenatal marijuana exposure on children's intellectual development at the age of six. Results concluded that the Cognitive deficits noticed at the age of six were specific to verbal and quantitative reasoning and short-term memory.

  7. Age 60 Study, Part 4: Experimental Evaluation of Pilot Performance

    DTIC Science & Technology

    1994-10-01

    and aging. Computerized cognitive test batteries, COGSREEN and WOMBAT , were selected as the domain-independent measures. Flitescript and whole task...were assessed. COGSCREEN total composite scores were significantly correlated with evaluator ratings on emergency/abnormal maneuvers. Neither WOMBAT ...B-3 WOMBAT Questionnaire .......................................... B-4 Sim ulator Post-flight Questionnaire

  8. Age-Related Differences in complex Monitoring Performance

    DTIC Science & Technology

    1981-04-01

    of- a low density oF active eccrine sweat glands in this age group and not necessarily an indication of lower autonomic arousal. If this is the case...and T. E. Bowman: Comparisons of Sweat Gland Counts, Electrodermal Activity, and liabitua- tion Behavior in Young and Old Groups of Subjects

  9. Improving Age Appropriate Social Skills To Enhance Academic Performance.

    ERIC Educational Resources Information Center

    Cheek, Lisa; Logan, Karen; Sprecher, Sharon; Streitmatter, Barbara

    This action research project examined the impact of a program for improving age-inappropriate behaviors that interfere with personal and academic progress. A total of 69 students from 3 elementary classrooms and 2 speech therapy groups were involved in the research. The targeted population consisted of fourth and sixth graders; students with…

  10. Verbosity and Projective Test Performance in the Aged.

    ERIC Educational Resources Information Center

    Hayslip, Bert, Jr.

    1981-01-01

    Investigated the extent to which response length influences Holtzman Inkblot Technique (HIT) scores in (N=102) elderly. Results suggest that response length has a pervasive effect on HIT scores and bears out the productivity of effects found in previous research with younger age cohorts. (JAC)

  11. Aging and Concurrent Task Performance: Cognitive Demand and Motor Control

    ERIC Educational Resources Information Center

    Albinet, Cedric; Tomporowski, Phillip D.; Beasman, Kathryn

    2006-01-01

    A motor task that requires fine control of upper limb movements and a cognitive task that requires executive processing--first performing them separately and then concurrently--was performed by 18 young and 18 older adults. The motor task required participants to tap alternatively on two targets, the sizes of which varied systematically. The…

  12. A Decade Comparison of Preterm Motor Performance at Age 4

    PubMed Central

    Sullivan, Mary C.; Hawes, Katheleen

    2012-01-01

    This was a prospective longitudinal study of two cohorts comprised of one full term and three premature infant groups born 10 years apart. Birth cohort, perinatal morbidity, and birth weight effects were investigated at age 4. Cohort 1 (1985–1989) had longer gestation, higher birth weight, and better Apgar scores than Cohort 2 (1996–1999), which had more intraventricular hemorrhage and bronchopulmonary dysplasia. Cohort and perinatal morbidity group, but not birth weight, predicted motor scores. Preterm Cohort 2 children had better oral motor, fine motor, and total motor scores, but lower visual motor integration scores than Cohort 1. Motor problems continue to affect preterm children at age 4, in particular those who experience perinatal morbidity, despite a decade of neonatal intensive care advancements. PMID:18022834

  13. Age-Related Changes in Performance and Recovery Kinetics in Masters Athletes: A Narrative Review.

    PubMed

    Borges, Nattai; Reaburn, Peter; Driller, Matthew; Argus, Christos

    2016-01-01

    Despite increasing participation rates in masters sport and extensive research examining age-related changes in performance, little is known about the effect of age on recovery kinetics in masters athletes. This narrative review focuses on the relationship between aging and sport participation, and the effect on both performance and recovery following an exercise bout. Current research suggests the effect of age on performance and recovery may be smaller than originally suggested and that increasing sedentary lifestyles appear to play a larger role in any observed decrements in performance and recovery in masters athletes. Currently, it appears that performance decrements are inevitable with age. However, performance capacities can be maintained through systematic physical training. Moreover, the limited current research suggests there may be an age effect on recovery kinetics following an exercise bout, although further research is required to understand the acute and chronic recovery processes in the masters athlete.

  14. Spatial-Sequential Working Memory in Younger and Older Adults: Age Predicts Backward Recall Performance within Both Age Groups.

    PubMed

    Brown, Louise A

    2016-01-01

    Working memory is vulnerable to age-related decline, but there is debate regarding the age-sensitivity of different forms of spatial-sequential working memory task, depending on their passive or active nature. The functional architecture of spatial working memory was therefore explored in younger (18-40 years) and older (64-85 years) adults, using passive and active recall tasks. Spatial working memory was assessed using a modified version of the Spatial Span subtest of the Wechsler Memory Scale - Third Edition (WMS-III; Wechsler, 1998). Across both age groups, the effects of interference (control, visual, or spatial), and recall type (forward and backward), were investigated. There was a clear effect of age group, with younger adults demonstrating a larger spatial working memory capacity than the older adults overall. There was also a specific effect of interference, with the spatial interference task (spatial tapping) reliably reducing performance relative to both the control and visual interference (dynamic visual noise) conditions in both age groups and both recall types. This suggests that younger and older adults have similar dependence upon active spatial rehearsal, and that both forward and backward recall require this processing capacity. Linear regression analyses were then carried out within each age group, to assess the predictors of performance in each recall format (forward and backward). Specifically the backward recall task was significantly predicted by age, within both the younger and older adult groups. This finding supports previous literature showing lifespan linear declines in spatial-sequential working memory, and in working memory tasks from other domains, but contrasts with previous evidence that backward spatial span is no more sensitive to aging than forward span. The study suggests that backward spatial span is indeed more processing-intensive than forward span, even when both tasks include a retention period, and that age predicts

  15. Spatial-Sequential Working Memory in Younger and Older Adults: Age Predicts Backward Recall Performance within Both Age Groups

    PubMed Central

    Brown, Louise A.

    2016-01-01

    Working memory is vulnerable to age-related decline, but there is debate regarding the age-sensitivity of different forms of spatial-sequential working memory task, depending on their passive or active nature. The functional architecture of spatial working memory was therefore explored in younger (18–40 years) and older (64–85 years) adults, using passive and active recall tasks. Spatial working memory was assessed using a modified version of the Spatial Span subtest of the Wechsler Memory Scale – Third Edition (WMS-III; Wechsler, 1998). Across both age groups, the effects of interference (control, visual, or spatial), and recall type (forward and backward), were investigated. There was a clear effect of age group, with younger adults demonstrating a larger spatial working memory capacity than the older adults overall. There was also a specific effect of interference, with the spatial interference task (spatial tapping) reliably reducing performance relative to both the control and visual interference (dynamic visual noise) conditions in both age groups and both recall types. This suggests that younger and older adults have similar dependence upon active spatial rehearsal, and that both forward and backward recall require this processing capacity. Linear regression analyses were then carried out within each age group, to assess the predictors of performance in each recall format (forward and backward). Specifically the backward recall task was significantly predicted by age, within both the younger and older adult groups. This finding supports previous literature showing lifespan linear declines in spatial-sequential working memory, and in working memory tasks from other domains, but contrasts with previous evidence that backward spatial span is no more sensitive to aging than forward span. The study suggests that backward spatial span is indeed more processing-intensive than forward span, even when both tasks include a retention period, and that age predicts

  16. Age-aware solder performance models : level 2 milestone completion.

    SciTech Connect

    Neilsen, Michael K.; Vianco, Paul Thomas; Neidigk, Matthew Aaron; Holm, Elizabeth Ann

    2010-09-01

    Legislated requirements and industry standards are replacing eutectic lead-tin (Pb-Sn) solders with lead-free (Pb-free) solders in future component designs and in replacements and retrofits. Since Pb-free solders have not yet seen service for long periods, their long-term behavior is poorly characterized. Because understanding the reliability of Pb-free solders is critical to supporting the next generation of circuit board designs, it is imperative that we develop, validate and exercise a solder lifetime model that can capture the thermomechanical response of Pb-free solder joints in stockpile components. To this end, an ASC Level 2 milestone was identified for fiscal year 2010: Milestone 3605: Utilize experimentally validated constitutive model for lead-free solder to simulate aging and reliability of solder joints in stockpile components. This report documents the completion of this milestone, including evidence that the milestone completion criteria were met and a summary of the milestone Program Review.

  17. Age 60 Study, Part 2: Airline Pilot Age and Performance - A Review of the Scientific Literature

    DTIC Science & Technology

    1994-10-01

    accomplish the research objectives of Tasks 4 and 5 of the Age 60 Project, two preliminary steps must be taken. Step 1 is to develop a high -level...investigate an information processing model of pilot decision making that takes into account pilot experience and stress. They found that low and high ...the third of a year (grouping months 1, 4 , 7 and 10; months 2, 5, 8, and 11; and months 3, 6, 9, and 12) before computing accident rates. Then three

  18. Tall Poppies: Bullying Behaviors Faced by Australian High-Performance School-Age Athletes

    ERIC Educational Resources Information Center

    O'Neill, Maureen; Calder, Angela; Allen, Bill

    2014-01-01

    Little is known about Australian high-performance school-age athletes' experiences as victims of the tall poppy syndrome. Tall poppies are successful individuals bullied by those who are less successful in order to "normalize them." Nineteen current or previous national or international high-performance school-age athletes were…

  19. Effects of Age and Visual-Motor Skills on Preschool Children's Computer-Game Performance.

    ERIC Educational Resources Information Center

    Strein, William

    1987-01-01

    The relationship of both age and visual-motor skills to performance on an arcade-like video game was studied with 16 preschool children. While age was positively related to performance, no significant relationship was found for the visual-motor skills variable. (Author/CB)

  20. Trait compensation and sex-specific aging of performance in male and female professional basketball players.

    PubMed

    Lailvaux, Simon P; Wilson, Robbie; Kasumovic, Michael M

    2014-05-01

    Phenotypic traits are often influenced by dynamic resource allocation trade-offs which, when occurring over the course of individual lifespan, may manifest as trait aging. Although aging is studied for a variety of traits that are closely tied to reproduction or reproductive effort, the aging of multiple traits related to fitness in other ways are less well understood. We took advantage of almost 30 years of data on human whole-organism performance in the National Basketball Association (USA) to examine trends of aging in performance traits associated with scoring. Given that patterns of aging differ between sexes in other animal species, we also analyzed a smaller dataset on players in the Women's National Basketball Association to test for potential sex differences in the aging of comparable traits. We tested the hypothesis that age-related changes in a specific aspect of overall performance can be compensated for by elevated expression of another, related aspect. Our analyses suggest that the aging of performance traits used in basketball is generally characterized by senescence in males, whereas age-related changes in basketball performance are less evident in females. Our data also indicate a different rate of senescence of different performance traits associated with scoring over a male's lifetime.

  1. Longitudinal psychomotor speed performance in human immunodeficiency virus-seropositive individuals: impact of age and serostatus.

    PubMed

    Sacktor, Ned; Skolasky, Richard L; Cox, Christopher; Selnes, Ola; Becker, James T; Cohen, Bruce; Martin, Eileen; Miller, Eric N

    2010-10-01

    Older human immunodeficiency virus-seropositive (HIV+) individuals (greater than age 50 years) are twice as likely to develop HIV dementia compared to younger HIV+ individuals. The objective of this study was to examine the impact of both age and serostatus on longitudinal changes in psychomotor speed/executive functioning performance among HIV+ and HIV− individuals. Four hundred and seventy-seven HIV+ and 799 HIV− individuals from the Multicenter AIDS Cohort Study (MACS) were subdivided into three age groups: (1) <40 years, (2) 40-50 years, and (3) >50 years. Psychomotor speed/executive functioning test performance was measured by the Symbol Digit Modalities Test (SDMT) and the Trail Making (TM) Test Parts A and B. Changes in performance were compared among the three age groups for both HIV+ and HIV− individuals. Among HIV+ individuals, on the TM Test Part B the younger group demonstrated improvement in performance over time (P = .007). The older and middle age groups demonstrated decline in performance over time (P = .041 and .030). The older group had a significantly different trajectory relative to the younger group (P = .046). Among the HIV− individuals, there was no effect of age on longitudinal performance. In conclusion, older HIV+ individuals show greater decline over time than younger HIV+ individuals on the TM Test Part B. Our results suggest that both HIV serostatus and age together may impact longitudinal performance on this test. Mild neurocognitive changes over time among older HIV+ individuals are likely to reflect age associated pathophysiological mechanisms including cerebrovascular risk factors.

  2. Performance trends in age group breaststroke swimmers in the FINA World Championships 1986-2014.

    PubMed

    Knechtle, Beat; Nikolaidis, Pantelis Theodoros; Rosemann, Thomas; Rüst, Christoph Alexander

    2016-10-31

    Performance trends in breaststroke swimmers competing at world class level in pool competitions are well investigated for elite swimmers, but not for age group swimmers. This study investigated trends in participation, performance and sex difference in performance in a total of 35,143 (16,160 women and 18,983 men) age group breaststroke swimmers aged 25-29 to 95-99 years competing in the Fédération Internationale de Natation (FINA) World Masters Championships between 1986 and 2014. Trends in participation were analysed using linear regression analyses and trends in performance were investigated using mixed-effects regression analyses with sex, distance and calendar year as fixed variables. Women and men improved performance in all age groups. For age groups 25-29 to 85-89 years, men were faster than women. For age groups 90-94 to 95-99 years, men were not faster than women. Sex and distance showed a significant interaction for all distances in age groups 25-29 to 80-84 years. In 50 m, women reduced the gap to men in age groups 40-44 to 70-74 years and in 100 m and 200 m, women reduced the gap in age groups 50-54 to 60-64 years. In summary, (i) women and men improved performance in all race distances and in all age groups, (ii) men were faster than women from 25 to 89 years, but not from 90 to 99 years, and (iii), women reduced the gap to men between ~40 and ~75 years, but not in younger (<40 years) or older (>75 years) age groups. Based on these findings for a time period of nearly 30 years, we may assume a further increase in participation and a further improvement in performance in the near future in age group breaststroke swimmers competing at world class level.

  3. Motor Skill Performance of School-Age Children with Visual Impairments

    ERIC Educational Resources Information Center

    Houwen, S.; Visscher, C.; Lemmink, K. A. P. M.; Hartman, E.

    2008-01-01

    The aim of this study was to examine the performance of children with visual impairments (VI) aged 7 to 10 years on different types of motor skills. Furthermore, the association between the degree of the VI and motor performance was examined. The motor performance of 48 children with VI (32 males, 16 females; mean age 8y 10mo [SD 1y 1mo]) was…

  4. Distinct Aging Effects on Functional Networks in Good and Poor Cognitive Performers

    PubMed Central

    Lee, Annie; Tan, Mingzhen; Qiu, Anqi

    2016-01-01

    Brain network hubs are susceptible to normal aging processes and disruptions of their functional connectivity are detrimental to decline in cognitive functions in older adults. However, it remains unclear how the functional connectivity of network hubs cope with cognitive heterogeneity in an aging population. This study utilized cognitive and resting-state functional magnetic resonance imaging data, cluster analysis, and graph network analysis to examine age-related alterations in the network hubs’ functional connectivity of good and poor cognitive performers. Our results revealed that poor cognitive performers showed age-dependent disruptions in the functional connectivity of the right insula and posterior cingulate cortex (PCC), while good cognitive performers showed age-related disruptions in the functional connectivity of the left insula and PCC. Additionally, the left PCC had age-related declines in the functional connectivity with the left medial prefrontal cortex (mPFC) and anterior cingulate cortex (ACC). Most interestingly, good cognitive performers showed age-related declines in the functional connectivity of the left insula and PCC with their right homotopic structures. These results may provide insights of neuronal correlates for understanding individual differences in aging. In particular, our study suggests prominent protection roles of the left insula and PCC and bilateral ACC in good performers. PMID:27667972

  5. The aging of elite male athletes: age-related changes in performance and skeletal muscle structure and function

    PubMed Central

    Faulkner, John A.; Davis, Carol S.; Mendias, Christopher L.; Brooks, Susan V.

    2009-01-01

    Objective The paper addresses the degree to which the attainment of the status as an elite athlete in different sports ameliorates the known age-related losses in skeletal muscle structure and function. Design The retrospective design, based on comparisons of published data on former elite and masters athletes and data on control subjects, assessed the degree to which the attainment of ‘elite and masters athlete status’ ameliorated the known age-related changes in skeletal muscle structure and function. Setting Institutional. Participants Elite male athletes. Interventions Participation in selected individual and team sports. Main Outcome Measurements Strength, power, VO2 max and performance. Results For elite athletes in all sports, as for the general population, age-related muscle atrophy begins at about 50 years of age. Despite the loss of muscle mass, elite athletes who maintain an active life style age gracefully with few health problems. Conversely, those who lapse into inactivity regress toward general population norms for fitness, weight control, and health problems. Elite athletes in the dual and team sports have careers that rarely extend into the thirties. Conclusions Life long physical activity does not appear to have any impact on the loss in fiber number. The loss of fibers can be buffered to some degree by hypertrophy of fibers that remain. Surprisingly, the performance of elite athletes in all sports appears to be impaired before the onset of the fiber loss. Even with major losses in physical capacity and muscle mass, the performance of elite and masters athletes is remarkable. PMID:19001883

  6. Relative improvements in endurance performance with age: evidence from 25 years of Hawaii Ironman racing.

    PubMed

    Lepers, Romuald; Rüst, Christoph A; Stapley, Paul J; Knechtle, Beat

    2013-06-01

    Despite of the growth of ultra-endurance sports events (of duration >6 h) over the previous few decades, the age-related declines in ultra-endurance performance have drawn little attention. The aim of the study was to analyse the changes in participation and performance trends of older (>40 years of age) triathletes between 1986 and 2010 at the Hawaii Ironman triathlon consisting of 3.8 km swimming, 180 km cycling and 42 km running. Swimming, cycling, running and total times of the best male and female triathletes between 18 and 69 years of age who competed in the Hawaii Ironman triathlon were analysed. The relative participation of master triathletes increased during the 1986-2010 period, while the participation of triathletes younger than 40 years of age decreased. Linear regression showed that males older than 44 years and females older than 40 years significantly improved their performances in the three disciplines and in the total time taken to complete the race. Gender differences in total time performance significantly decreased in the same time period for all age groups between the 40-44 and 55-59 years ones. The reasons for these relative improvements of Ironman athlete performances in older age groups remain, however, unknown. Further studies investigating training regimes, competition experience or sociodemographic factors are needed to gain better insights into the phenomenon of increasing participation and improvement of ultra-endurance performance with advancing age.

  7. Development of Self-Consciousness: At What Age Does Audience Pressure Disrupt Performance?

    ERIC Educational Resources Information Center

    Tice, Dianne M.; And Others

    1985-01-01

    Hypothesized that audience pressure would prove most detrimental to the skilled performance of adolescents (due to vulnerability to self-awareness) but not of children. Performances of skilled players of video games with and without audience indicated a curvilinear relationship between age and performance change which confirmed the hypothesis.…

  8. The age of peak performance in Ironman triathlon: a cross-sectional and longitudinal data analysis

    PubMed Central

    2013-01-01

    Background The aims of the present study were, firstly, to investigate in a cross-sectional analysis the age of peak Ironman performance within one calendar year in all qualifiers for Ironman Hawaii and Ironman Hawaii; secondly, to determine in a longitudinal analysis on a qualifier for Ironman Hawaii whether the age of peak Ironman performance and Ironman performance itself change across years; and thirdly, to determine the gender difference in performance. Methods In a cross-sectional analysis, the age of the top ten finishers for all qualifier races for Ironman Hawaii and Ironman Hawaii was determined in 2010. For a longitudinal analysis, the age and the performance of the annual top ten female and male finishers in a qualifier for Ironman Hawaii was determined in Ironman Switzerland between 1995 and 2010. Results In 19 of the 20 analyzed triathlons held in 2010, there was no difference in the age of peak Ironman performance between women and men (p > 0.05). The only difference in the age of peak Ironman performance between genders was in ‘Ironman Canada’ where men were older than women (p = 0.023). For all 20 races, the age of peak Ironman performance was 32.2 ± 1.5 years for men and 33.0 ± 1.6 years for women (p > 0.05). In Ironman Switzerland, there was no difference in the age of peak Ironman performance between genders for top ten women and men from 1995 to 2010 (F = 0.06, p = 0.8). The mean age of top ten women and men was 31.4 ± 1.7 and 31.5 ± 1.7 years (Cohen's d = 0.06), respectively. The gender difference in performance in the three disciplines and for overall race time decreased significantly across years. Men and women improved overall race times by approximately 1.2 and 4.2 min/year, respectively. Conclusions Women and men peak at a similar age of 32–33 years in an Ironman triathlon with no gender difference. In a qualifier for Ironman Hawaii, the age of peak Ironman performance remained unchanged across years. In contrast, gender

  9. The Impact of Simulated Aging on Nursing Staff Self Reports of Job Satisfaction and Performance.

    ERIC Educational Resources Information Center

    Robinson, James D.; Nussbaum, Jon F.

    A study examined the impact of a simulated aging experience on nursing staff perceptions of job satisfaction and job performance. It was hypothesized that nurses and nurse aides who participated in the simulated aging experience would be more satisfied with their jobs and would receive fewer complaints from residents than those who did not…

  10. Relationship of Age and Education to Halstead Test Performance in Different Patient Populations

    ERIC Educational Resources Information Center

    Prigatano, George P.; Parsons, Oscar A.

    1976-01-01

    The effects of age and education on Halstead test performance were examined in this cross-validation of the Vega and Parsons study. Differences between correlation in psychiatric patients and medical-surgical control subjects are discussed, as is the importance of age, and differences in reference groups when making clinical inferences about brain…

  11. Writing and Drawing Performance of School Age Children: Is There Any Relationship?

    ERIC Educational Resources Information Center

    Bonoti, Fotini; Vlachos, Filippos; Metallidou, Panagiota

    2005-01-01

    The aim of our study was to investigate possible relationships between writing and drawing performance of school-aged children, in order to compare the two skills at the within-individual level. The sample consisted of 182 right- and left-handed children, aged 8 to 12 years. Children were examined by the Greek adaptation of the Luria-Nebraska…

  12. How Do Groups Work? Age Differences in Performance and the Social Outcomes of Peer Collaboration

    ERIC Educational Resources Information Center

    Leman, Patrick J.

    2015-01-01

    Do children derive different benefits from group collaboration at different ages? In the present study, 183 children from two age groups (8.8 and 13.4 years) took part in a class quiz as members of a group, or individually. In some groups, cohesiveness was made salient by awarding prizes to the top performing groups. In other groups, prizes were…

  13. Preschool Experience in 10 Countries: Cognitive and Language Performance at Age 7

    ERIC Educational Resources Information Center

    Montie, Jeanne E.; Xiang, Zongping; Schweinhart, Lawrence J.

    2006-01-01

    The IEA Preprimary Project is a longitudinal, cross-national study of preprimary care and education designed to identify how process and structural characteristics of the settings children attended at age 4 are related to their age-7 cognitive and language performance. Investigators collaborated to develop common instruments to measure family…

  14. [Predictive value of Ages & Stages Questionnaires for cognitive performance at early years of schooling].

    PubMed

    Schonhaut B, Luisa; Pérez R, Marcela; Castilla F, Ana María; Castro M, Sonia; Salinas A, Patricia; Armijo R, Iván

    2017-02-01

    The Ages and Stages questionnaires (ASQ) has been recently validated in our country for developmental screening. The objective of this study is evaluate the validity of ASQ to predict low cognitive performance in the early years of schooling.

  15. Aging performance for masters records in athletics, swimming, rowing, cycling, triathlon, and weightlifting.

    PubMed

    Baker, A Barry; Tang, Yong Q

    2010-10-01

    Record performances for Masters sporting events for swimming, cycling, triathlon, rowing, and weightlifting were analyzed and then compared with the authors' previously published results for Masters running, walking, and jumping sports events. Records were normalized using the 30s age records as a baseline, and studied through the various age ranges to the 90s. A curvilinear mathematical model [y = 1 - exp((T - T(0))/τ)] was again used for the major comparisons, along with slope changes using a linear model [y = α(T -T'0)] across the age groupings. All sports declined with increasing age, with rowing showing the least deterioration. Performances in running, swimming, and walking were reasonably well maintained, followed by greater decline with age for cycling, triathlon, and jumping events. Weightlifting showed the fastest and greatest decline with increasing age. The relative performances for women, when compared with men's performances for these Masters events, was approximately 80% to 85%, with jumping at 73% and weightlifting at 52%. These relative performances compared with World Record comparisons of approximately 90% (with weightlifting at approximately 75%). All these results show no greater decline with age for endurance events over the sprint events, though there was a greater decline for the strength events of weightlifting and jumping. There may be real physiological differences for these strength events, or there may be other explanations such as training or competitive considerations or smaller numbers participating.

  16. Dissociating Effects of Global SWS Disruption and Healthy Aging on Waking Performance and Daytime Sleepiness

    PubMed Central

    Groeger, John A.; Stanley, Neil; Deacon, Stephen; Dijk, Derk-Jan

    2014-01-01

    Study Objective: To contrast the effects of slow wave sleep (SWS) disruption and age on daytime functioning. Design: Daytime functioning was contrasted in three age cohorts, across two parallel 4-night randomized groups (baseline, two nights of SWS disruption or control, recovery sleep). Setting: Sleep research laboratory. Participants: 44 healthy young (20-30 y), 35 middle-aged (40-55 y), and 31 older (66-83 y) men and women. Interventions: Acoustic stimulation contingent on appearance of slow waves. Measurements and Results: Cognitive performance was assessed before sleep latency tests at five daily time-points. SWS disruption resulted in less positive affect, slower or impaired information processing and sustained attention, less precise motor control, and erroneous implementation, rather than inhibition, of well-practiced actions. These performance impairments had far smaller effect sizes than the increase in daytime sleepiness and differed from baseline to the same extent for each age group. At baseline, younger participants performed better than older participants across many cognitive domains, with largest effects on executive function, response time, sustained attention, and motor control. At baseline, the young were sleepier than other age groups. Conclusions: SWS has been considered a potential mediator of age-related decline in performance, although the effects of SWS disruption on daytime functioning have not been quantified across different cognitive domains nor directly compared to age-related changes in performance. The data imply that two nights of SWS disruption primarily leads to an increase in sleepiness with minor effects on other aspects of daytime functioning, which are different from the substantial effects of age. Citation: Groeger JA, Stanley N, Deacon S, Dijk DJ. Dissociating effects of global sws disruption and healthy aging on waking performance and daytime sleepiness. SLEEP 2014;37(6):1127-1142. PMID:24882908

  17. The effect of plant aging on equipment qualification and human performance issues related to license renewal

    SciTech Connect

    Gunther, W.E.; Higgins, J.C. ); Aggarwal, S.K. )

    1991-01-01

    The aging of nuclear power plants is one of the most important issues facing the nuclear industry worldwide. Aging encompasses as forms of degradation to nuclear power plant components, systems, and structures that result from exposure to environmental conditions or from operational stresses. Both the degradation from aging and actions taken to address the aging, such as increased maintenance and testing, can significantly impact human performance in the plant. Research into the causes and effects of aging as obtained through the assessment of operating experience and testing have raised questions regarding the adequacy of existing industry standards for addressing the concerns raised by this research. This paper discusses these issues, with particular emphasis in the area of equipment qualification and human performance.

  18. The effect of plant aging on equipment qualification and human performance issues related to license renewal

    SciTech Connect

    Gunther, W.E.; Higgins, J.C.; Aggarwal, S.K.

    1991-12-31

    The aging of nuclear power plants is one of the most important issues facing the nuclear industry worldwide. Aging encompasses as forms of degradation to nuclear power plant components, systems, and structures that result from exposure to environmental conditions or from operational stresses. Both the degradation from aging and actions taken to address the aging, such as increased maintenance and testing, can significantly impact human performance in the plant. Research into the causes and effects of aging as obtained through the assessment of operating experience and testing have raised questions regarding the adequacy of existing industry standards for addressing the concerns raised by this research. This paper discusses these issues, with particular emphasis in the area of equipment qualification and human performance.

  19. Do negative views of aging influence memory and auditory performance through self-perceived abilities?

    PubMed

    Chasteen, Alison L; Pichora-Fuller, M Kathleen; Dupuis, Kate; Smith, Sherri; Singh, Gurjit

    2015-12-01

    Memory and hearing are critical domains that interact during older adults' daily communication and social encounters. To develop a more comprehensive picture of how aging influences performance in these domains, the roles of social variables such as views of aging and self-perceived abilities need greater examination. The present study investigates the linkages between views of aging, self-perceived abilities, and performance within and across the domains of memory and hearing, connections that have never been examined together within the same sample of older adults. For both domains, 301 older adults completed measures of their views of aging, their self-perceived abilities and behavioral tests. Using structural equation modeling, we tested a hypothesized model in which older adults' negative views of aging predicted their performance in the domains of memory and hearing through negatively affecting their self-perceived abilities in those domains. Although this model achieved adequate fit, an alternative model in which hearing performance predicted self-perceived hearing also was supported. Both models indicate that hearing influences memory with respect to both behavioral and self-perception measures and that negative views of aging influence self-perceptions in both domains. These results highlight the importance of views of aging and self-perceptions of abilities within and across these domains.

  20. Visuospatial working memory in very preterm and term born children--impact of age and performance.

    PubMed

    Mürner-Lavanchy, I; Ritter, B C; Spencer-Smith, M M; Perrig, W J; Schroth, G; Steinlin, M; Everts, R

    2014-07-01

    Working memory is crucial for meeting the challenges of daily life and performing academic tasks, such as reading or arithmetic. Very preterm born children are at risk of low working memory capacity. The aim of this study was to examine the visuospatial working memory network of school-aged preterm children and to determine the effect of age and performance on the neural working memory network. Working memory was assessed in 41 very preterm born children and 36 term born controls (aged 7-12 years) using functional magnetic resonance imaging (fMRI) and neuropsychological assessment. While preterm children and controls showed equal working memory performance, preterm children showed less involvement of the right middle frontal gyrus, but higher fMRI activation in superior frontal regions than controls. The younger and low-performing preterm children presented an atypical working memory network whereas the older high-performing preterm children recruited a working memory network similar to the controls. Results suggest that younger and low-performing preterm children show signs of less neural efficiency in frontal brain areas. With increasing age and performance, compensational mechanisms seem to occur, so that in preterm children, the typical visuospatial working memory network is established by the age of 12 years.

  1. Intraindividual Variability in Basic Reaction Time Predicts Middle-Aged and Older Pilots’ Flight Simulator Performance

    PubMed Central

    2013-01-01

    Objectives. Intraindividual variability (IIV) is negatively associated with cognitive test performance and is positively associated with age and some neurological disorders. We aimed to extend these findings to a real-world task, flight simulator performance. We hypothesized that IIV predicts poorer initial flight performance and increased rate of decline in performance among middle-aged and older pilots. Method. Two-hundred and thirty-six pilots (40–69 years) completed annual assessments comprising a cognitive battery and two 75-min simulated flights in a flight simulator. Basic and complex IIV composite variables were created from measures of basic reaction time and shifting and divided attention tasks. Flight simulator performance was characterized by an overall summary score and scores on communication, emergencies, approach, and traffic avoidance components. Results. Although basic IIV did not predict rate of decline in flight performance, it had a negative association with initial performance for most flight measures. After taking into account processing speed, basic IIV explained an additional 8%–12% of the negative age effect on initial flight performance. Discussion. IIV plays an important role in real-world tasks and is another aspect of cognition that underlies age-related differences in cognitive performance. PMID:23052365

  2. Cortical grey matter content is associated with both age and bimanual performance, but is not observed to mediate age-related behavioural decline.

    PubMed

    van Ruitenbeek, Peter; Serbruyns, Leen; Solesio-Jofre, Elena; Meesen, Raf; Cuypers, Koen; Swinnen, Stephan P

    2017-01-01

    Declines in both cortical grey matter and bimanual coordination performance are evident in healthy ageing. However, the relationship between ageing, bimanual performance, and grey matter loss remains unclear, particularly across the whole adult lifespan. Therefore, participants (N = 93, range 20-80 years) performed a complex Bimanual Tracking Task, and structural brain images were obtained using magnetic resonance imaging. Analyses revealed that age correlated negatively with task performance. Voxel-based morphometry analysis revealed that age was associated with grey matter declines in task-relevant cortical areas and that grey matter in these areas was negatively associated with task performance. However, no evidence for a mediating effect of grey matter in age-related bimanual performance decline was observed. We propose a new hypothesis that functional compensation may account for the observed absence of mediation, which is in line with the observed pattern of increased inter-individual variance in performance with age.

  3. Physical performance characteristics of high-level female soccer players 12-21 years of age.

    PubMed

    Vescovi, J D; Rupf, R; Brown, T D; Marques, M C

    2011-10-01

    Performance assessment has become an invaluable component of monitoring player development and within talent identification programs in soccer, yet limited performance data are available for female soccer players across a wide age range. The aim of this study was to describe the physical performance characteristics of female soccer players ranging in age from 12 to 21 years. High-level female soccer players (n=414) were evaluated on linear sprinting (36.6 m with 9.1 m splits), countermovement jump (CMJ), and two agility tests. Separate one-way ANOVAs were used to compare performance characteristics between (1) each year of chronological age and (2) three age groups: 12-13 years, n=78, 14-17 years, n=223, and 18-21 years, n=113. Mean linear sprint speed over 9.1 m was similar across all chronological ages, however sprint speed over the final 9.1 m, CMJ height and agility scores improved until approximately 15-16 years. Outcomes from the group data indicated better performance on all tests for the 14-17-year-old group compared with the 12-13-year-old group. Additionally, sprint speed on the second and fourth 9.1 m splits and 36.6 m sprint speed as well as performance on the Illinois agility test was better in the 18-21-year-old group compared with the 14-17-year-old group. The findings from this study indicate that marked improvements of high intensity short duration work occur up until 15-16 years. Smaller gains in performance were observed beyond 16 years of age as evidenced by better performance on 36.6 m sprint speed, several sprint splits and the Illinois agility test in the college aged players (i.e., 18-21-year-old group).

  4. Age-related changes in conventional road versus off-road triathlon performance.

    PubMed

    Lepers, Romuald; Stapley, Paul J

    2011-08-01

    The aims of this study were: (i) to analyze age-related declines in swimming, cycling, and running performances for road-based and off-road triathlons, and (ii) to compare age-related changes in these three disciplines between road-based and off-road triathlons. Swimming, cycling, running and total time performances of the top five males between 20 and 70 years of age (in 5-year intervals) were analyzed for short distance road-based (1.5 km swim, 40 km cycle, and 10 km run) and off-road (1.5 km swim, 30 km mountain bike, and 11 km trail run) triathlons at the 2009 World Championships. Independently of age, there was a lesser age-related decline in cycling performance (P < 0.01) compared to running and swimming for road-based triathlon. In contrast, age-related decline did not differ between the three locomotion modes for off-road triathlon. With advancing age, the performance decline was less pronounced (P < 0.01) for road-based than for off-road triathlon in swimming (≥65 years), cycling (≥50 years), running (≥60 years), and total event (≥55 years) times, respectively. These results suggest that the rate of the decline in performance for off-road triathlon is greater than for road-based triathlon, indicating that the type of discipline (road vs. mountain bike cycling and road vs. trail running) exerts an important influence on the magnitude of the age-associated changes in triathlon performance.

  5. Macro- and micro-structural white matter differences correlate with cognitive performance in healthy aging.

    PubMed

    Marques, Paulo César Gonçalves; Soares, José Miguel Montenegro; Magalhães, Ricardo José da Silva; Santos, Nadine Correia; Sousa, Nuno Jorge Carvalho

    2016-03-01

    Studies have shown that white matter (WM) volumetric reductions and overall degradation occur with aging. Nonetheless little is known about the WM alterations that may underlie different cognitive status in older individuals. The main goal of the present work was to identify and characterize possible macro and microstructural WM alterations that could distinguish between older healthy individuals with contrasting cognitive profiles (i.e., "poor" vs "good" cognitive performers). Structural and diffusion magnetic resonance imaging was performed in order to quantify local WM volumes, white matter signal abnormalities (WMSA) volume (a measure of lesion burden) and diffusion tensor imaging scalar maps known to probe WM microstructure. A battery of neurocognitive/psychological tests was administered to assess the cognitive performance. Poor performers showed a higher slope for the positive association between WMSA volume and age compared to good performers. Even when controlling for WMSA volume, poor performers also evidenced lower fractional anisotropy, as well as positive associations with age with higher slopes of regression parameters in radial and axial diffusivity. Altogether results suggest that cognitive performance is related to differences in WM, with poor cognitive performers displaying signs of faster aging in WM.

  6. Effects of Attentional Focus and Age on Suprapostural Task Performance and Postural Control

    ERIC Educational Resources Information Center

    McNevin, Nancy; Weir, Patricia; Quinn, Tiffany

    2013-01-01

    Purpose: Suprapostural task performance (manual tracking) and postural control (sway and frequency) were examined as a function of attentional focus, age, and tracking difficulty. Given the performance benefits often found under external focus conditions, it was hypothesized that external focus instructions would promote superior tracking and…

  7. Analysis of performance and age of the fastest 100-mile ultra-marathoners worldwide

    PubMed Central

    Rüst, Christoph Alexander; Knechtle, Beat; Rosemann, Thomas; Lepers, Romuald

    2013-01-01

    OBJECTIVES: The performance and age of peak ultra-endurance performance have been investigated in single races and single race series but not using worldwide participation data. The purpose of this study was to examine the changes in running performance and the age of peak running performance of the best 100-mile ultra-marathoners worldwide. METHOD: The race times and ages of the annual ten fastest women and men were analyzed among a total of 35,956 finishes (6,862 for women and 29,094 for men) competing between 1998 and 2011 in 100-mile ultra-marathons. RESULTS: The annual top ten performances improved by 13.7% from 1,132±61.8 min in 1998 to 977.6±77.1 min in 2011 for women and by 14.5% from 959.2±36.4 min in 1998 to 820.6±25.7 min in 2011 for men. The mean ages of the annual top ten fastest runners were 39.2±6.2 years for women and 37.2±6.1 years for men. The age of peak running performance was not different between women and men (p>0.05) and showed no changes across the years. CONCLUSION: These findings indicated that the fastest female and male 100-mile ultra-marathoners improved their race time by ∼14% across the 1998–2011 period at an age when they had to be classified as master athletes. Future studies should analyze longer running distances (>200 km) to investigate whether the age of peak performance increases with increased distance in ultra-marathon running. PMID:23778421

  8. Personality Traits, Facets and Cognitive Performance: Age Differences in Their Relations

    PubMed Central

    Graham, Eileen K.; Lachman, Margie E.

    2014-01-01

    Personality traits and cognitive performance are related, but little work has examined how these associations vary by personality facet or age. 154 adults aged 22 to 84 completed the Brief Test of Adult Cognition by Telephone (BTACT) and the NEO Five Factor Personality Inventory. Hierarchical multiple regression analyses showed negative emotional aspects of personality (neuroticism, depression) were associated with lower reasoning, and social aspects of personality (assertiveness) were associated with faster reaction time, yet lower reasoning. The association between neuroticism and performance was found primarily among younger adults. In older adulthood, better performance was associated with positive emotional aspects of personality. We discuss how personality may have different associations with performance across age and the implications for possible interventions. PMID:24821992

  9. Professional expertise does not eliminate age differences in imagery-based memory performance during adulthood.

    PubMed

    Lindenberger, U; Kliegl, R; Baltes, P B

    1992-12-01

    Using a testing-the-limits paradigm, the authors investigated the modulation (attenuation) of negative adult age differences in imagery-based memory performance as a function of professional expertise. Six older graphic designers, 6 normal older adults, 6 younger graphic design students, and 6 normal younger students participated in a 19-session program with a cued-recall variant of the Method of Loci. Older graphic designers attained higher levels of mnemonic performance than normal older adults but were not able to reach younger adults' level of performance; a perfect separation of age groups was achieved. Spatial visualization was a good predictor of mnemonic performance. Results suggest that negative adult age differences in imagery-based memory are attenuated but not eliminated by the advantages associated with criterion-relevant ability (talent) and experience.

  10. Effect of Age Group on Technical-Tactical Performance Profile of the Serve in Men's Volleyball.

    PubMed

    García-de-Alcaraz, Antonio; Ortega, Enrique; Palao, José M

    2016-10-01

    The aim of this study was to analyze the technical-tactical performance profile of the serve for various age groups and categories of competition in men's volleyball. The sample comprised 13,262 serves performed by 986 players in 299 sets observed in various categories of competition (U-14, U-16, U-19, national senior, and international senior). An observational design was used. The variables studied were category of competition, type of execution, and serve performance. The results showed that for higher age groups (senior categories), there were significantly fewer jump serves and poorer serve performance, regardless of players' maturity and training development. The use of the jump serves increased the serve risk while attempting to hinder the organization of the opponent attack. This paper discusses the serve evolution and the implications on the training process at the different age groups in men's volleyball.

  11. Personality Traits, Facets and Cognitive Performance: Age Differences in Their Relations.

    PubMed

    Graham, Eileen K; Lachman, Margie E

    2014-03-01

    Personality traits and cognitive performance are related, but little work has examined how these associations vary by personality facet or age. 154 adults aged 22 to 84 completed the Brief Test of Adult Cognition by Telephone (BTACT) and the NEO Five Factor Personality Inventory. Hierarchical multiple regression analyses showed negative emotional aspects of personality (neuroticism, depression) were associated with lower reasoning, and social aspects of personality (assertiveness) were associated with faster reaction time, yet lower reasoning. The association between neuroticism and performance was found primarily among younger adults. In older adulthood, better performance was associated with positive emotional aspects of personality. We discuss how personality may have different associations with performance across age and the implications for possible interventions.

  12. Supervisor-subordinate age dissimilarity and performance ratings: the buffering effects of supervisory relationship and practice.

    PubMed

    Van der Heijden, Beatrice I J M; Scholarios, Dora; Van der Schoot, Esther; Jedrzejowicz, Piotr; Bozionelos, Nikos; Epitropaki, Olga; Knauth, Peter; Marzec, Izabela; Mikkelsen, Aslaug; Van der Heijde, Claudia

    2010-01-01

    Using 394 pairs of employees and their immediate supervisors working in the Information and Communication Technology (ICT) sector in three northern European countries, this study examined the effect of workplace moderators on the link between relational demography and supervisor ratings of performance. Directional age differences between superior and subordinate (i.e., status incongruence caused when the supervisor is older or younger than his/her subordinate) and non-directional age differences were used as predictors of supervisor ratings of occupational expertise. The quality of the supervisor-subordinate relationship and the existence of positive age-related supervisory practices were examined as moderators of this relationship. The results provide no support for a relationship between directional age differences and age-related stereotyping by supervisors in ratings of performance, neither for the effects of age-related supervisory practices. However, high quality supervisor-subordinate relationships did moderate the effects of age dissimilarity on supervisory ratings. The implications of these findings for performance appraisal methodologies and recommendations for further research are discussed.

  13. Cognitive performance and age-related changes in the hippocampal proteome

    PubMed Central

    Freeman, Willard M.; VanGuilder, Heather D.; Bennett, Colleen; Sonntag, William E.

    2008-01-01

    Declining cognitive performance is associated with increasing age, even in the absence of overt pathological processes. We and others have reported that declining cognitive performance is associated with age-related changes in brain glucose utilization, long-term potentiation and paired-pulse facilitation, protein expression, neurotransmitter levels, and trophic factors. However, it is unclear whether these changes are causes or symptoms of the underlying alterations in dendritic and synaptic morphology that occur with age. In this study, we examined the hippocampal proteome for age- and cognition-associated changes in behaviorally stratified young and old rats, using 2-DIGE and MS/MS-MS. Comparison of old cognitively intact with old cognitively impaired animals revealed additional changes that would not have been detected otherwise. Interestingly, not all age-related changes in protein expression were associated with cognitive decline, and distinct differences in protein expression were found when comparing old cognitively intact with old cognitively impaired rats. A large number of protein changes with age were related to the glycolysis/gluconeogenesis pathway. In total, the proteomic changes suggest that age-related alterations act synergistically with other perturbations to result in cognitive decline. This study also demonstrates the importance of examining behaviorally-defined animals in proteomic studies, as comparison of young to old animals regardless of behavioral performance would have failed to detect many cognitive impairment-specific protein expression changes evident when behavioral stratification data was used. PMID:19135133

  14. Cross-age effect in recognition performance and memory monitoring for faces.

    PubMed

    Bryce, Margaret S; Dodson, Chad S

    2013-03-01

    The cross-age effect refers to the finding of better memory for own- than other-age faces. We examined 3 issues about this effect: (1) Does it extend to the ability to monitor the likely accuracy of memory judgments for young and old faces? (2) Does it apply to source information that is associated with young and old faces? And (3) what is a likely mechanism underlying the cross-age effect? In Experiment 1, young and older adults viewed young and old faces appearing in different contexts. Young adults exhibited a cross-age effect in their recognition of faces and in their memory-monitoring performance for these faces. Older adults, by contrast, showed no age-of-face effects. Experiment 2 examined whether young adults' cross-age effect depends on or is independent of encoding a mixture of young and old faces. Young adults encoded either a mixture of young and old faces, a set of all young faces, or a set of all old faces. In the mixed-list condition we replicated our finding of young adults' superior memory for own-age faces; in the pure-list conditions, however, there were absolutely no differences in performance between young and old faces. The fact that the pure-list design abolishes the cross-age effect supports social-cognitive theories of this phenomenon.

  15. Lifespan Changes in the Countermanding Performance of Young and Middle Aged Adult Rats

    PubMed Central

    Beuk, Jonathan; Beninger, Richard J.; Paré, Martin

    2016-01-01

    Inhibitory control can be investigated with the countermanding task, which requires subjects to make a response to a go signal and cancel that response when a stop signal is presented occasionally. Adult humans performing the countermanding task typically exhibit impaired response time (RT), stop signal response time (SSRT) and response accuracy as they get older, but little change in post-error slowing. Rodent models of the countermanding paradigm have been developed recently, yet none have directly examined age-related changes in performance throughout the lifespan. Male Wistar rats (N = 16) were trained to respond to a visual stimulus (go signal) by pressing a lever directly below an illuminated light for food reward, but to countermand the lever press subsequent to a tone (stop signal) that was presented occasionally (25% of trials) at a variable delay. Subjects were tested in 1 h sessions at approximately 7 and 12 months of age with intermittent training in between. Rats demonstrated longer go trial RT, a higher proportion of go trial errors and performed less total trials at 12, compared to 7 months of age. Consistent SSRT and post-error slowing were observed for rats at both ages. These results suggest that the countermanding performance of rats does vary throughout the lifespan, in a manner similar to humans, suggesting that rodents may provide a suitable model for behavioral impairment related to normal aging. These findings also highlight the importance of indicating the age at which rodents are tested in countermanding investigations. PMID:27555818

  16. Finisher and performance trends in female and male mountain ultramarathoners by age group

    PubMed Central

    Rüst, Christoph Alexander; Knechtle, Beat; Eichenberger, Evelyn; Rosemann, Thomas; Lepers, Romuald

    2013-01-01

    Background This study examined changes according to age group in the number of finishers and running times for athletes in female and male mountain ultramarathoners competing in the 78 km Swiss Alpine Marathon, the largest mountain ultramarathon in Europe and held in high alpine terrain. Methods The association between age and performance was investigated using analysis of variance and both single and multilevel regression analyses. Results Between 1998 and 2011, a total of 1,781 women and 12,198 men finished the Swiss Alpine Marathon. The number of female finishers increased (r2 = 0.64, P = 0.001), whereas the number of male finishers (r2 = 0.18, P = 0.15) showed no change. The annual top ten men became older and slower, whereas the annual top ten women became older but not slower. Regarding the number of finishers in the age groups, the number of female finishers decreased in the age group 18–24 years, whereas the number of finishers increased in the age groups 30–34, 40–44, 45–49, 50–54, 55–59, 60–64, and 70–74 years. In the age groups 25–29 and 35–39 years, the number of finishers showed no changes across the years. In the age group 70–74 years, the increase in number of finishers was linear. For all other age groups, the increase was exponential. For men, the number of finishers decreased in the age groups 18–24, 25–29, 30–34, and 35–39 years. In the age groups 40–44, 45–49, 50–54, 55–59, 60–64, 70–74, and 75–79 years, the number of finishers increased. In the age group 40–44 years, the increase was linear. For all other age groups, the increase was exponential. Female finishers in the age group 40–44 years became faster over time. For men, finishers in the age groups 18–24, 25–29, 30–34, 40–44, and 45–49 years became slower. Conclusion The number of women older than 30 years and men older than 40 years increased in the Swiss Alpine Marathon. Performance improved in women aged 40–44 years but

  17. The role of spatial abilities and age in performance in an auditory computer navigation task.

    PubMed

    Pak, Richard; Czaja, Sara J; Sharit, Joseph; Rogers, Wendy A; Fisk, Arthur D

    2006-01-01

    Age-related differences in spatial ability have been suggested as a mediator of age-related differences in computer-based task performance. However, the vast majority of tasks studied have primarily used a visual display (e.g., graphical user interfaces). In the current study, the relationship between spatial ability and performance in a non-visual computer-based navigation task was examined in a sample of 196 participants ranging in age from 18 to 91. Participants called into a simulated interactive voice response system and carried out a variety of transactions. They also completed measures of attention, working memory, and spatial abilities. The results showed that age-related differences in spatial ability predicted a significant amount of variance in performance in the non-visual computer task, even after controlling for other abilities. Understanding the abilities that influence performance with technology may provide insight into the source of age-related performance differences in the successful use of technology.

  18. The role of spatial abilities and age in performance in an auditory computer navigation task

    PubMed Central

    Pak, Richard; Czaja, Sara J.; Sharit, Joseph; Rogers, Wendy A.; Fisk, Arthur D.

    2008-01-01

    Age-related differences in spatial ability have been suggested as a mediator of age-related differences in computer-based task performance. However, the vast majority of tasks studied have primarily used a visual display (e.g., graphical user interfaces). In the current study, the relationship between spatial ability and performance in a non-visual computer-based navigation task was examined in a sample of 196 participants ranging in age from 18 to 91. Participants called into a simulated interactive voice response system and carried out a variety of transactions. They also completed measures of attention, working memory, and spatial abilities. The results showed that age-related differences in spatial ability predicted a significant amount of variance in performance in the non-visual computer task, even after controlling for other abilities. Understanding the abilities that influence performance with technology may provide insight into the source of age-related performance differences in the successful use of technology. PMID:18997876

  19. Review of performance, medical, and operational data on pilot aging issues

    NASA Technical Reports Server (NTRS)

    Stoklosa, J. H.

    1992-01-01

    An extensive review of the literature and studies relating to performance, medical, operational, and legal data regarding pilot aging issues was performed in order to determine what evidence there is, if any, to support mandatory pilot retirement. Popular misconceptions about aging, including the failure to distinguish between the normal aging process and disease processes that occur more frequently in older individuals, continue to contribute to much of the misunderstanding and controversy that surround this issue. Results: Review of medical data related to the pilot aging issue indicate that recent improvement in medical diagnostics and treatment technology have made it possible to identify to a high degree individuals who are at risk for developing sudden incapacitating illness and for treating those with disqualifying medical conditions. Performance studies revealed that after controlling for the presence of disease states, older pilots are able to perform as well as younger pilots on many performance tasks. Review of accident data showed that older, healthy pilots do not have higher accident rates than younger pilots, and indeeed, evidence suggests that older pilots have an advantage in the cockpit due to higher experience levels. The Man-Machine-Mission-Environment interface of factors can be managed through structured, supervised, and enhanced operations, maintenance, flight reviews, and safety procedures in order to ensure safe and productive operations by reducing the margin of error and by increasing the margin of safety. Conclusions: There is no evidence indicating any specific age as an arbitrary cut-off point for pilots to perform their fight duties. A combination of regular medical screening, performance evaluation, enhanced operational maintenance, and safety procedures can most effectively ensure a safe pilot population than can a mandatory retirement policy based on arbitrary age restrictions.

  20. The impact of green roof ageing on substrate characteristics and hydrological performance

    NASA Astrophysics Data System (ADS)

    De-Ville, Simon; Menon, Manoj; Jia, Xiaodong; Reed, George; Stovin, Virginia

    2017-04-01

    Green roofs contribute to stormwater management through the retention of rainfall and the detention of runoff. However, there is very limited knowledge concerning the evolution of green roof hydrological performance with system age. This study presents a non-invasive technique which allows for repeatable determination of key substrate characteristics over time, and evaluates the impact of observed substrate changes on hydrological performance. The physical properties of 12 green roof substrate cores have been evaluated using non-invasive X-ray microtomography (XMT) imaging. The cores comprised three replicates of two contrasting substrate types at two different ages: unused virgin samples; and 5-year-old samples from existing green roof test beds. Whilst significant structural differences (density, pore and particle sizes, tortuosity) between virgin and aged samples of a crushed brick substrate were observed, these differences did not significantly affect hydrological characteristics (maximum water holding capacity and saturated hydraulic conductivity). A contrasting substrate based upon a light expanded clay aggregate experienced increases in the number of fine particles and pores over time, which led to increases in maximum water holding capacity of 7%. In both substrates, the saturated hydraulic conductivity estimated from the XMT images was lower in aged compared with virgin samples. Comparisons between physically-derived and XMT-derived substrate hydrological properties showed that similar values and trends in the data were identified, confirming the suitability of the non-invasive XMT technique for monitoring changes in engineered substrates over time. The observed effects of ageing on hydrological performance were modelled as two distinct hydrological processes, retention and detention. Retention performance was determined via a moisture-flux model using physically-derived values of virgin and aged maximum water holding capacity. Increased water holding

  1. Interaction between age of irradiation and age of testing in the disruption of operant performance using a ground-based model for exposure to cosmic rays.

    PubMed

    Rabin, Bernard M; Joseph, James A; Shukitt-Hale, Barbara; Carrihill-Knoll, Kirsty L

    2012-02-01

    Previous research has shown a progressive deterioration in cognitive performance in rats exposed to (56)Fe particles as a function of age. The present experiment was designed to evaluate the effects of age of irradiation independently of the age of testing. Male Fischer-344 rats, 2, 7, 12, and 16 months of age, were exposed to 25-200 cGy of (56)Fe particles (1,000 MeV/n). Following irradiation, the rats were trained to make an operant response on an ascending fixed-ratio reinforcement schedule. When performance was evaluated as a function of both age of irradiation and testing, the results showed a significant effect of age on the dose needed to produce a performance decrement, such that older rats exposed to lower doses of (56)Fe particles showed a performance decrement compared to younger rats. When performance was evaluated as a function of age of irradiation with the age of testing held constant, the results indicated that age of irradiation was a significant factor influencing operant responding, such that older rats tested at similar ages and exposed to similar doses of (56)Fe particles showed similar performance decrements. The results are interpreted as indicating that the performance decrement is not a function of age per se, but instead is dependent upon an interaction between the age of irradiation, the age of testing, and exposure to HZE particles. The nature of these effects and how age of irradiation affects cognitive performance after an interval of 15 to 16 months remains to be established.

  2. Growth curve analyses of the relationship between early maternal age and children's mathematics and reading performance.

    PubMed

    Torres, D Diego

    2015-03-01

    Regarding the methods used to examine the early maternal age-child academic outcomes relationship, the extant literature has tended to examine change using statistical analyses that fail to appreciate that individuals vary in their rates of growth. Of the one study I have been able to find that employs a true growth model to estimate this relationship, the authors only controlled for characteristics of the maternal household after family formation; confounding background factors of mothers that might select them into early childbearing, a possible source of bias, were ignored. The authors' findings nonetheless suggested an inverse relationship between early maternal age, i.e., a first birth between the ages of 13 and 17, and Canadian adolescents' mean math performance at age 10. Early maternal age was not related to the linear slope of age. To elucidate whether the early maternal age-child academic outcomes association, treated in a growth context, is consistent with this finding, the present study built on it using US data and explored children's mathematics and reading trajectories from age 5 on. Its unique contribution is that it further explicitly controlled for maternal background factors and employed a three-level growth model with repeated measures of children nested within their mothers. Though the strength of the relationship varied between mean initial academic performance and mean academic growth, results confirmed that early maternal age was negatively related to children's mathematics and reading achievement, net of post-teen first birth child-specific and maternal household factors. Once maternal background factors were included, there was no statistically significant relationship between early maternal age and either children's mean initial mathematics and reading scores or their mean mathematics and reading growth.

  3. Changes in brain network efficiency and working memory performance in aging.

    PubMed

    Stanley, Matthew L; Simpson, Sean L; Dagenbach, Dale; Lyday, Robert G; Burdette, Jonathan H; Laurienti, Paul J

    2015-01-01

    Working memory is a complex psychological construct referring to the temporary storage and active processing of information. We used functional connectivity brain network metrics quantifying local and global efficiency of information transfer for predicting individual variability in working memory performance on an n-back task in both young (n = 14) and older (n = 15) adults. Individual differences in both local and global efficiency during the working memory task were significant predictors of working memory performance in addition to age (and an interaction between age and global efficiency). Decreases in local efficiency during the working memory task were associated with better working memory performance in both age cohorts. In contrast, increases in global efficiency were associated with much better working performance for young participants; however, increases in global efficiency were associated with a slight decrease in working memory performance for older participants. Individual differences in local and global efficiency during resting-state sessions were not significant predictors of working memory performance. Significant group whole-brain functional network decreases in local efficiency also were observed during the working memory task compared to rest, whereas no significant differences were observed in network global efficiency. These results are discussed in relation to recently developed models of age-related differences in working memory.

  4. Age-dependent effects of carotid endarterectomy or stenting on cognitive performance.

    PubMed

    Wasser, Katrin; Hildebrandt, Helmut; Gröschel, Sonja; Stojanovic, Tomislav; Schmidt, Holger; Gröschel, Klaus; Pilgram-Pastor, Sara M; Knauth, Michael; Kastrup, Andreas

    2012-11-01

    Although evidence is accumulating that age modifies the risk of carotid angioplasty and stenting (CAS) versus endarterectomy (CEA) for patients with significant carotid stenosis, the impact of age on cognition after either CEA or CAS remains unclear. In this study, we analyzed the effects of age on cognitive performance after either CEA or CAS using a comprehensive neuropsychological test battery with parallel test forms and a control group to exclude a learning effect. The neuropsychological outcomes after revascularization were determined in 19 CAS and 27 CEA patients with severe carotid stenosis. The patients were subdivided according to their median age (<68 years and ≥68 years); 27 healthy subjects served as a control group. In all patients clinical examinations, MRI scans and a neuropsychological test battery that assessed four major cognitive domains were performed immediately before, within 72 h, and 3 months after CEA or CAS. While patients <68 years of age showed no significant cognitive alteration after either CEA or CAS, a significant cognitive decline was observed in patients ≥68 years in both treatment groups (p = 0.001). Notably, this cognitive deterioration persisted in patients after CEA, whereas it was only transient in patients treated with CAS. These results demonstrate an age-dependent effect of CEA and CAS on cognitive functions. In contrast to the recently observed increased clinical complication rates in older subjects after CAS compared with CEA, CEA appears to be associated with a greater, persistent decline in cognitive performance than CAS in this subgroup of patients.

  5. Implications of Advancing Paternal Age: Does It Affect Offspring School Performance?

    PubMed Central

    Svensson, Anna C.; Abel, Kathryn; Dalman, Christina; Magnusson, Cecilia

    2011-01-01

    Average paternal age is increasing in many high income countries, but the implications of this demographic shift for child health and welfare are poorly understood. There is equivocal evidence that children of older fathers are at increased risk of neurodevelopmental disorders and reduced IQ. We therefore report here on the relationship between paternal age and a composite indicator of scholastic achievement during adolescence, i.e. compulsory school leaving grades, among recent birth cohorts in Stockholm County where delayed paternity is notably common. We performed a record-linkage study comprising all individuals in Stockholm County who finished 9 years of compulsory school from 2000 through 2007 (n = 155,875). Data on school leaving grades and parental characteristics were retrieved from administrative and health service registers and analyzed using multiple linear regression. Advancing paternal age at birth was not associated with a decrease in school leaving grades in adolescent offspring. After adjustment for year of graduation, maternal age and parental education, country of birth and parental mental health service use, offspring of fathers aged 50 years or older had on average 0.3 (95% CI −3.8, 4.4) points higher grades than those of fathers aged 30–34 years. In conclusion, advancing paternal age is not associated with poorer school performance in adolescence. Adverse effects of delayed paternity on offspring cognitive function, if any, may be counterbalanced by other potential advantages for children born to older fathers. PMID:21957460

  6. Motor skill performance of school-age children with visual impairments.

    PubMed

    Houwen, S; Visscher, C; Lemmink, K A P M; Hartman, E

    2008-02-01

    The aim of this study was to examine the performance of children with visual impairments (VI) aged 7 to 10 years on different types of motor skills. Furthermore, the association between the degree of the VI and motor performance was examined. The motor performance of 48 children with VI (32 males, 16 females; mean age 8y 10mo [SD 1y 1mo]) was assessed using the Movement Assessment Battery for Children (MABC). Their performance was compared with 48 children without VI (33 males, 15 females; mean age 8y 9mo [SD 1y 1mo]). Children with VI showed the poorest performance compared with peers without VI on unimanual speed, eye-hand coordination, catching, static balance, and dynamic balance while moving slowly. There was no significant difference between children with moderate and severe VI, except for bimanual coordination in 7- to 8-year-olds and eye-hand coordination in both the 7- to 8-year-olds and 9- to 10-year-olds, favouring the children with moderate VI. The poor performance compared with children without VI is related to vision, but the degree of the VI does not appear to relate to motor performance, except when associated with bimanual and eye-hand coordination. For children with VI, it seems very important to adjust the environmental context and task to enhance motor performance.

  7. Association of pulsatile and mean cerebral blood flow velocity with age and neuropsychological performance.

    PubMed

    Pase, Matthew P; Grima, Natalie A; Stough, Con; Scholey, Andrew; Pipingas, Andrew

    2014-05-10

    Low cerebral blood flow velocity is associated with cognitive decline. However, the association between pulsatile brain blood flow velocity and cognition has not been investigated. High pulsatile hemodynamic stress in the brain may impair cognitive function through damage to small cerebral vessels. The current objective was to examine the cross-sectional association of pulsatile and mean cerebral blood flow velocity with age and neuropsychological performance. We also examined whether cerebral blood flow velocity was associated with aortic pulse pressure, a measure of arterial ageing and aortic stiffness. Cerebral blood flow velocity was measured in the middle cerebral artery using Transcranial Doppler Ultrasonography (TDU) while neuropsychological performance was measured using a computerized cognitive test battery. Aortic pulse pressure was non-invasively derived from applanation tonometry of the radial artery. The sample comprised 160 healthy adults aged 50-70 years. Results indicated that increasing age correlated with lower mean (r=-0.23, p<0.01) and higher pulsatile (r=0.27, p<0.01) brain blood flow velocity. In multivariate adjusted models, both peripheral (β=0.28, p<0.05) and aortic (β=0.24, p<0.05) pulse pressure were associated with higher pulsatile flow velocity through the middle cerebral artery. In adjusted models, neither mean nor pulsatile cerebral blood flow velocity was associated with performance on any cognitive task. In conclusion, arterial ageing was associated with increased pulsatile hemodynamic stress in the brain. However, this was not associated with impaired neuropsychological performance.

  8. Aging's effects on marathon performance insights from the New York City race.

    PubMed

    Santos-Lozano, Alejandro; Angulo, Ana M; Collado, Pilar S; Sanchis-Gomar, Fabian; Pareja-Galeano, Helios; Fiuza-Luces, Carmen; Lucia, Alejandro; Garatachea, Nuria

    2015-10-01

    Most studies on aging and marathon have analyzed elite marathoners, yet the latter only represent a very small fraction of all marathon participants. In addition, analysis of variance or unpaired Student t tests are frequently used to compare mean performance times across age groups. In this report the authors propose an alternative methodology to determine the impact of aging on marathon performance in both nonelite and elite marathoners participating in the New York City Marathon. In all, 471,453 data points corresponding to 370,741 different runners over 13 race editions (1999-2011) were retrieved. Results showed that the effect of aging on marathon performance was overall comparable in both sexes, the effect of aging differed between the fastest and slowest runners in both sexes, and the magnitude of the sex differences was higher in the slowest runners than in the fastest ones. Current data suggest that the biological differences between sexes allow men to have better marathon performance across most of the human life span.

  9. Performance of the Breast Cancer Risk Assessment Tool Among Women Aged 75 Years and Older

    PubMed Central

    Li, Vicky W.; Eliassen, A. Heather; Davis, Roger B.; LaCroix, Andrea Z.; McCarthy, Ellen P.; Rosner, Bernard A.; Chlebowski, Rowan T.; Rohan, Thomas E.; Hankinson, Susan E.; Marcantonio, Edward R.; Ngo, Long H.

    2016-01-01

    Background: The Breast Cancer Risk Assessment Tool (BCRAT, “Gail model”) is commonly used for breast cancer prediction; however, it has not been validated for women age 75 years and older. Methods: We used Nurses’ Health Study (NHS) data beginning in 2004 and Women’s Health Initiative (WHI) data beginning in 2005 to compare BCRAT’s performance among women age 75 years and older with that in women age 55 to 74 years in predicting five-year breast cancer incidence. BCRAT risk factors include: age, race/ethnicity, age at menarche, age at first birth, family history, history of benign breast biopsy, and atypia. We examined BCRAT’s calibration by age by comparing expected/observed (E/O) ratios of breast cancer incidence. We examined discrimination by computing c-statistics for the model by age. All statistical tests were two-sided. Results: Seventy-three thousand seventy-two NHS and 97 081 WHI women participated. NHS participants were more likely to be non-Hispanic white (96.2% vs 84.7% in WHI, P < .001) and were less likely to develop breast cancer (1.8% vs 2.0%, P = .02). E/O ratios by age in NHS were 1.16 (95% confidence interval [CI] = 1.09 to 1.23, age 57–74 years) and 1.31 (95% CI = 1.18 to 1.45, age ≥ 75 years, P = .02), and in WHI 1.03 (95% CI = 0.97 to 1.09, age 55–74 years) and 1.10 (95% CI = 1.00 to 1.21, age ≥ 75 years, P = .21). E/O ratio 95% confidence intervals crossed one among women age 75 years and older when samples were limited to women who underwent mammography and were without significant illness. C-statistics ranged between 0.56 and 0.58 in both cohorts regardless of age. Conclusions: BCRAT accurately predicted breast cancer for women age 75 years and older who underwent mammography and were without significant illness but had modest discrimination. Models that consider individual competing risks of non–breast cancer death may improve breast cancer risk prediction for older women. PMID:26625899

  10. Age-related changes in 100-km ultra-marathon running performance.

    PubMed

    Knechtle, Beat; Rüst, Christoph Alexander; Rosemann, Thomas; Lepers, Romuald

    2012-08-01

    The aims of this study were (1) to investigate the participation and performance trends at the '100 km Lauf Biel' in Switzerland from 1998 to 2010, and (2) to compare the age-related changes in 100-km running performance between males and females. For both sexes, the percent of finishers significantly (P < 0.01) decreased for the 18-29 and the 30-39-year age groups, while it significantly (P < 0.01) increased for the 40-49 and the 50-59-year age groups over the studied period. From 1998 to 2010, the mean age of the top ten finishers increased by 0.4 years per annum for both females (P = 0.02) and males (P = 0.003). The running time for the top ten finishers remained stable for females, while it significantly (P = 0.001) increased by 2.4 min per annum for males. There was a significant (P < 0.001) age effect on running times for both sexes. The best 100-km running times was observed for the age comprised between 30 and 49 years for males, and between 30 and 54 years for females, respectively. The age-related decline in running performance was similar until 60-64 years between males and females, but was greater for females compared to males after 65 years. Future studies should investigate the lifespan from 65 to 75 years to better understand the performance difference between male and female master ultra-marathoners.

  11. Aging affects spatial reconstruction more than spatial pattern separation performance even after extended practice.

    PubMed

    Clark, Rachel; Tahan, Asli C; Watson, Patrick D; Severson, Joan; Cohen, Neal J; Voss, Michelle

    2017-03-21

    Although the hippocampus experiences age-related anatomical and functional deterioration, the effects of aging vary across hippocampal-dependent cognitive processes. In particular, whether or not the hippocampus is known to be required for a spatial memory process is not an accurate predictor on its own of whether aging will affect performance. Therefore, the primary objective of this study was to compare the effects of healthy aging on a test of spatial pattern separation and a test of spatial relational processing, which are two aspects of spatial memory that uniquely emphasize the use of multiple hippocampal-dependent processes. Spatial pattern separation supports spatial memory by preserving unique representations for distinct locations. Spatial relational processing forms relational representations of objects to locations or between objects and other objects in space. To test our primary objective, 30 young (18-30 years; 21F) and 30 older participants (60-80 years; 21F) all completed a spatial pattern separation task and a task designed to require spatial relational processing through spatial reconstruction. To ensure aging effects were not due to inadequate time to develop optimal strategies or become comfortable with the testing devices, a subset of participants had extended practice across three sessions on each task. Results showed that older adults performed more poorly than young on the spatial reconstruction task that emphasized the use of spatial relational processing, and that age effects persisted even after controlling for pattern separation performance. Further, older adults performed more poorly on spatial reconstruction than young adults even after three testing sessions each separated by 7-10 days, suggesting effects of aging are resistant to extended practice and likely reflect genuine decline in hippocampal memory abilities.

  12. Martial Art Training and Cognitive Performance in Middle-Aged Adults

    PubMed Central

    Douris, Peter; Douris, Christopher; Balder, Nicole; LaCasse, Michael; Rand, Amir; Tarapore, Freya; Zhuchkan, Aleskey; Handrakis, John

    2015-01-01

    Cognitive performance includes the processes of attention, memory, processing speed, and executive functioning, which typically declines with aging. Previous research has demonstrated that aerobic and resistance exercise improves cognitive performance immediately following exercise. However, there is limited research examining the effect that a cognitively complex exercise such as martial art training has on these cognitive processes. Our study compared the acute effects of 2 types of martial art training to aerobic exercise on cognitive performance in middle-aged adults. We utilized a repeated measures design with the order of the 3 exercise conditions randomly assigned and counterbalanced. Ten recreational middle-aged martial artists (mean age = 53.5 ± 8.6 years) participated in 3 treatment conditions: a typical martial art class, an atypical martial art class, and a one-hour walk at a self-selected speed. Cognitive performance was assessed by the Stroop Color and Word test. While all 3 exercise conditions improved attention and processing speed, only the 2 martial art conditions improved the highest order of cognitive performance, executive function. The effect of the 2 martial art conditions on executive function was not different. The improvement in executive function may be due to the increased cortical demand required by the more complex, coordinated motor tasks of martial art exercise compared to the more repetitive actions of walking. PMID:26672872

  13. Martial Art Training and Cognitive Performance in Middle-Aged Adults.

    PubMed

    Douris, Peter; Douris, Christopher; Balder, Nicole; LaCasse, Michael; Rand, Amir; Tarapore, Freya; Zhuchkan, Aleskey; Handrakis, John

    2015-09-29

    Cognitive performance includes the processes of attention, memory, processing speed, and executive functioning, which typically declines with aging. Previous research has demonstrated that aerobic and resistance exercise improves cognitive performance immediately following exercise. However, there is limited research examining the effect that a cognitively complex exercise such as martial art training has on these cognitive processes. Our study compared the acute effects of 2 types of martial art training to aerobic exercise on cognitive performance in middle-aged adults. We utilized a repeated measures design with the order of the 3 exercise conditions randomly assigned and counterbalanced. Ten recreational middle-aged martial artists (mean age = 53.5 ± 8.6 years) participated in 3 treatment conditions: a typical martial art class, an atypical martial art class, and a one-hour walk at a self-selected speed. Cognitive performance was assessed by the Stroop Color and Word test. While all 3 exercise conditions improved attention and processing speed, only the 2 martial art conditions improved the highest order of cognitive performance, executive function. The effect of the 2 martial art conditions on executive function was not different. The improvement in executive function may be due to the increased cortical demand required by the more complex, coordinated motor tasks of martial art exercise compared to the more repetitive actions of walking.

  14. Aging

    PubMed Central

    Park, Dong Choon

    2013-01-01

    Aging is initiated based on genetic and environmental factors that operate from the time of birth of organisms. Aging induces physiological phenomena such as reduction of cell counts, deterioration of tissue proteins, tissue atrophy, a decrease of the metabolic rate, reduction of body fluids, and calcium metabolism abnormalities, with final progression onto pathological aging. Despite the efforts from many researchers, the progression and the mechanisms of aging are not clearly understood yet. Therefore, the authors would like to introduce several theories which have gained attentions among the published theories up to date; genetic program theory, wear-and-tear theory, telomere theory, endocrine theory, DNA damage hypothesis, error catastrophe theory, the rate of living theory, mitochondrial theory, and free radical theory. Although there have been many studies that have tried to prevent aging and prolong life, here we introduce a couple of theories which have been proven more or less; food, exercise, and diet restriction. PMID:24653904

  15. Interaction between age of irradiation and age of testing in the disruption of operant performance using a ground-based model for exposure to cosmic rays

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Exposure to HZE particles produces deficits in cognitive performance. While previous research has shown a progressive deterioration in cognitive performance in radiated rats as a function of age, the present experiment was designed to evaluate the effects of age of irradiation independently of the ...

  16. Effect of Preexercise Creatine Ingestion on Muscle Performance in Healthy Aging Males.

    PubMed

    Baker, Taylor P; Candow, Darren G; Farthing, Jonathan P

    2016-06-01

    Preexercise creatine supplementation may have a beneficial effect on aging muscle performance. Using a double-blind, repeated measures, crossover design, healthy males (N = 9, 54.8 ± 4.3 years; 92.9 ± 11.5 kg; 179.2 ± 11.1 cm) were randomized to consume creatine (20 g) and placebo (20 g corn starch maltodextrin), on 2 separate occasions (7 days apart), 3 hours before performing leg press and chest press repetitions to muscle fatigue (3 sets at 70% 1-repetition maximum; 1 minute rest between sets). There was a set main effect (p ≤ 0.05) for the leg press and chest press with the number of repetitions performed decreasing similarly for creatine and placebo. These results suggest that a bolus ingestion of creatine consumed 3 hours before resistance exercise has no effect on upper or lower-body muscle performance in healthy aging males.

  17. The age of the best ultramarathon performance - the case of the "Comrades Marathon".

    PubMed

    Knechtle, Beat; Nikolaidis, Pantelis Theodoros

    2017-01-01

    The aim of the present study was to determine the age of the fastest running speed in 202,370 runners (34,090 women and 168,280 men) competing in the "Comrades Marathon" between 1994 and 2015 using non-linear regression analysis (second order polynomial function). When all runners were considered in 1-year age intervals, the fastest running speed (9.61 ± 1.65 km/h) was achieved at the age of 29.89 years in men, whereas women achieved it at the age of 35.96 years 8.60 ± 1.10 km/h. When the fastest runners were considered in 1-year intervals, the fastest running speed (16.65 km/h) was achieved in men at the age of 36.38 years. For the fastest women, the age of the fastest running speed (13.89 km/h) was 32.75 years. To summarize, for all runners, men achieved the best ultramarathon performance ~6 years earlier than women. When the fastest runners were considered, however, men achieved the best performance ~4 years later than women.

  18. Resting-state slow wave power, healthy aging and cognitive performance.

    PubMed

    Vlahou, Eleni L; Thurm, Franka; Kolassa, Iris-Tatjana; Schlee, Winfried

    2014-05-29

    Cognitive functions and spontaneous neural activity show significant changes over the life-span, but the interrelations between age, cognition and resting-state brain oscillations are not well understood. Here, we assessed performance on the Trail Making Test and resting-state magnetoencephalographic (MEG) recordings from 53 healthy adults (18-89 years old) to investigate associations between age-dependent changes in spontaneous oscillatory activity and cognitive performance. Results show that healthy aging is accompanied by a marked and linear decrease of resting-state activity in the slow frequency range (0.5-6.5 Hz). The effects of slow wave power on cognitive performance were expressed as interactions with age: For older (>54 years), but not younger participants, enhanced delta and theta power in temporal and central regions was positively associated with perceptual speed and executive functioning. Consistent with previous work, these findings substantiate further the important role of slow wave oscillations in neurocognitive function during healthy aging.

  19. Sex difference in race performance and age of peak performance in the Ironman Triathlon World Championship from 1983 to 2012

    PubMed Central

    2012-01-01

    Background The fastest Ironman race times in ‘Ironman Hawaii’ were achieved in very recent years. This study investigated the change in sex difference in both race performance and the age of peak performance across years in the top ten athletes for split disciplines and overall race time in the ‘Ironman Hawaii’ between 1983 and 2012. Methods Changes in split times, overall race times, and age of athletes across years for the top ten overall and the fastest swimmers, cyclists, and runners were investigated using regression analyses and analyses of variance. Results Between 1983 and 2012, the overall top ten men and women finishers improved their swimming (only men), cycling, running, and overall race times. The sex difference in overall race time decreased significantly (p = 0.01) from 15.2% to 11.3% across time. For the split disciplines, the sex difference remained unchanged (p > 0.05) for swimming (12.5 ± 3.7%) and cycling (12.5 ± 2.7%) but decreased for running from 13.5 ± 8.1% to 7.3 ± 2.9% (p = 0.03). The time performance of the top ten swimmers remained stable (p > 0.05), while those of the top ten cyclists and top ten runners improved (p < 0.01). The sex difference in performance remained unchanged (p > 0.05) in swimming (8.0 ± 2.4%), cycling (12.7 ± 1.8%), and running (15.2 ± 3.0%). Between 1983 and 2012, the age of the overall top ten finishers and the fastest swimmers, cyclists, and runners increased across years for both women and men (p < 0.01). Conclusions To summarize, for the overall top ten finishers, the sex difference decreased across years for overall race time and running, but not for swimming and cycling. For the top ten per discipline, the sex difference in performance remained unchanged. The athletes improved their performances across years although the age of peak performance increased. PMID:23849215

  20. The relative age effect and the influence on performance in youth alpine ski racing.

    PubMed

    Müller, Lisa; Hildebrandt, Carolin; Raschner, Christian

    2015-03-01

    The relative age effect (RAE), which refers to an over representation of athletes born early in a selection year, recently was proven to be present in alpine skiing. However, it was not made apparent whether the RAE exists as early as at the youngest level of youth ski racing at national level, nor whether the relative age influences racing performance. As a consequence, the purpose of the present study was twofold: first, to examine the extent of the RAE and second, to assess the influence the relative age has on the overall performance at the youngest levels of youth ski racing. The study included the investigation of 1,438 participants of the Austrian Kids Cup and 1,004 participants of the Teenager Cup at the provincial level, as well as 250 finalists of the Kids Cup and 150 finalists of the Teenager Cup at the national level. Chi²-tests revealed a highly significant RAE already at the youngest level of youth ski racing (Kids Cup) at both the provincial and national levels. There are not again favorably selected the relatively older athletes from the first into the second level of youth ski racing (Teenager Cup). Among the athletes of the Kids Cup, the relative age quarter distribution differed highly significantly from the distribution of the total sample with an over representation of relatively older athletes by comparison taking the top three positions. The data revealed that relative age had a highly significant influence on performance. This study demonstrated that the RAE poses a problem as early as the youngest level of youth ski racing, thereby indicating that many young talented kids are discriminated against, diminishing any chance they might have of becoming elite athletes despite their talents and efforts. The RAE influences not only the participation rate in alpine skiing, but also the performances. As a result, changes in the talent development system are imperative. Key pointsThe relative age influences not only the participation in youth ski

  1. [Determination of writing age of blue ballpoint pen inks by high performance liquid chromatography].

    PubMed

    Shi, Xiao-Fan; Li, Xin-Qian; Xu, Ying-Jian; Wang, Jing-Han; Wang, Yan-Ji

    2006-09-01

    As it is a frequently encountered problem in the laboratory of forensic science nowadays to distinguish whether the questioned documents, such as deeds, contracts, and receipts, written in ballpoint pen inks are true or not, and identify the writing age of them, it is very essential to establish a simple, sensitive and accurate method to examine the similarities and differences of the ballpoint pen inks and identify the writing age. The present paper introduces a technique that allows identifying the kind and the writing age of the blue ballpoint pen inks. The technique is based on using a high performance liquid chromatographic method for distinguishing the similarities and differences in dyes of blue ballpoint pen inks and determining changes in dyes of blue ballpoint pen inks developed with age, and these changes can be evaluated by the ratio of peak areas.

  2. Effects of reaction time variability and age on brain activity during Stroop task performance.

    PubMed

    Tam, Angela; Luedke, Angela C; Walsh, Jeremy J; Fernandez-Ruiz, Juan; Garcia, Angeles

    2015-09-01

    Variability in reaction time during task performance may reflect fluctuations in attention and cause reduced performance in goal-directed tasks, yet it is unclear whether the mechanisms behind this phenomenon change with age. Using fMRI, we tested young and cognitively healthy older adults with the Stroop task to determine whether aging affects the neural mechanisms underlying intra-individual reaction time variability. We found significant between-group differences in BOLD activity modulated by reaction time. In older adults, longer reaction times were associated with greater activity in frontoparietal attentional areas, while in younger adults longer reaction times were associated with greater activity in default mode network areas. Our results suggest that the neural correlates of reaction time variability change with healthy aging, reinforcing the concept of functional plasticity to maintain high cognitive function throughout the lifespan.

  3. [The association between paid or voluntary employment and neuropsychological test performance at an older age].

    PubMed

    Weghorst, Ronan B W M; Scherder, Erik J A; Oosterman, Joukje M

    2017-04-01

    Studies have convincingly shown that both physical and mental activity are positively associated with cognitive task performance in aging. Little is known, however, about whether still being employed or doing volunteer work, which obviously engages physical and/or mental activity, is similarly associated with cognitive ability at an older age. The current study explored this relationship in 28 volunteers aged sixty years and older. Participants completed a neuropsychological test battery, and data regarding the number of working hours (paid and voluntary) per week were collected. A total of 28 participants were included, 13 of whom worked three or more hours per week. As a group, these active participants achieved better episodic memory, sustained attention and psychomotor speed results. This study shows that older people who are still working demonstrate better neuropsychological task performance. An important question for future research concerns the causality of this relationship.

  4. Effects of psychiatric history on cognitive performance in old-age depression

    PubMed Central

    Pantzar, Alexandra; Atti, Anna Rita; Bäckman, Lars; Laukka, Erika J.

    2015-01-01

    Cognitive deficits in old-age depression vary as a function of multiple factors; one rarely examined factor is long-term psychiatric history. We investigated effects of psychiatric history on cognitive performance in old-age depression and in remitted persons. In the population-based Swedish National Study on Aging and Care in Kungsholmen study, older persons (≥60 years) without dementia were tested with a cognitive battery and matched to the Swedish National Inpatient Register (starting 1969). Participants were grouped according to current depression status and psychiatric history and compared to healthy controls (n = 96). Group differences were observed for processing speed, attention, executive functions, and verbal fluency. Persons with depression and psychiatric inpatient history (n = 20) and late-onset depression (n = 49) performed at the lowest levels, whereas cognitive performance in persons with self-reported recurrent unipolar depression (n = 52) was intermediate. Remitted persons with inpatient history of unipolar depression (n = 38) exhibited no cognitive deficits. Heart disease burden, physical inactivity, and cumulative inpatient days modulated the observed group differences in cognitive performance. Among currently depressed persons, those with inpatient history, and late onset performed at the lowest levels. Importantly, remitted persons showed no cognitive deficits, possibly reflecting the extended time since the last admission (m = 15.6 years). Thus, the present data suggest that cognitive deficits in unipolar depression may be more state- than trait-related. Information on profiles of cognitive performance, psychiatric history, and health behaviors may be useful in tailoring individualized treatment. PMID:26175699

  5. Cerebral White Matter Integrity Mediates Adult Age Differences in Cognitive Performance

    PubMed Central

    Madden, David J.; Spaniol, Julia; Costello, Matthew C.; Bucur, Barbara; White, Leonard E.; Cabeza, Roberto; Davis, Simon W.; Dennis, Nancy A.; Provenzale, James M.; Huettel, Scott A.

    2009-01-01

    Previous research has established that age-related decline occurs in measures of cerebral white matter integrity, but the role of this decline in age-related cognitive changes is not clear. To conclude that white matter integrity has a mediating (causal) contribution, it is necessary to demonstrate that statistical control of the white matter-cognition relation reduces the magnitude of age-cognition relation. In this research, we tested the mediating role of white matter integrity, in the context of a task switching paradigm involving word categorization. Participants were 20 healthy, community-dwelling older adults (60–85 years), and 20 younger adults (18–27 years). From diffusion tensor imaging (DTI) tractography, we obtained fractional anisotropy (FA) as an index of white matter integrity in the genu and splenium of the corpus callosum and the superior longitudinal fasciculus (SLF). Mean FA values exhibited age-related decline consistent with a decrease in white matter integrity. From a model of reaction time distributions, we obtained independent estimates of the decisional and nondecisional (perceptual-motor) components of task performance. Age-related decline was evident in both components. Critically, age differences in task performance were mediated by FA in two regions: the central portion of the genu, and splenium-parietal fibers in the right hemisphere. This relation held only for the decisional component and was not evident in the nondecisional component. This result is the first demonstration that the integrity of specific white matter tracts is a mediator of age-related changes in cognitive performance. PMID:18564054

  6. Experience-Based Mitigation of Age-Related Performance Declines: Evidence From Air Traffic Control

    PubMed Central

    Nunes, Ashley; Kramer, Arthur F.

    2010-01-01

    Previous research has found age-related deficits in a variety of cognitive processes. However, some studies have demonstrated age-related sparing on tasks where individuals have substantial experience, often attained over many decades. Here, the authors examined whether decades of experience in a fast-paced demanding profession, air traffic control (ATC), would enable older controllers to perform at high levels of proficiency. The authors also investigated whether older controllers would show diminished age-related decrements on domain-relevant cognitive abilities. Both young and old controllers and noncontrollers performed a battery of cognitive and ATC tasks. Results indicate that although high levels of experience can reduce the magnitude of age-related decline on the component processes that underlie complex task performance, this sparing is limited in scope. More important, however, the authors observed experience-based sparing on simulated ATC tasks, with the sparing being most evident on the more complex air traffic control tasks. These results suggest that given substantial experience, older adults may be quite capable of performing at high levels of proficiency on fast-paced demanding real-world tasks. The implications of these findings for global skilled labor shortages are discussed. PMID:19309213

  7. Age-Related Visual Changes and Their Impications for the Motor Skill Performance of Older Adults.

    ERIC Educational Resources Information Center

    Haywood, Kathleen M.; Trick, Linda R.

    Physical changes in and conditions of the eye associated with the normal aging process are discussed with reference to their impact on performance in physical and recreational activities. Descriptions are given of characteristic changes in visual acuity in the areas of: (1) presbyopia (inability to clearly focus near images); (2) sensitivity to…

  8. Age-Related Differences in Reaction Time Task Performance in Young Children

    ERIC Educational Resources Information Center

    Kiselev, Sergey; Espy, Kimberlay Andrews; Sheffield, Tiffany

    2009-01-01

    Performance of reaction time (RT) tasks was investigated in young children and adults to test the hypothesis that age-related differences in processing speed supersede a "global" mechanism and are a function of specific differences in task demands and processing requirements. The sample consisted of 54 4-year-olds, 53 5-year-olds, 59…

  9. Supervisor-Subordinate Age Dissimilarity and Performance Ratings: The Buffering Effects of Supervisory Relationship and Practice

    ERIC Educational Resources Information Center

    Van der Heijden, Beatrice I. J. M.; Scholarios, Dora; Van der Schoot, Esther; Jedrzejowicz, Piotr; Bozionelos, Nikos; Epitropaki, Olga; Knauth, Peter; Marzec, Izabela; Mikkelsen, Aslaug; Van der Heijde, Claudia

    2010-01-01

    Using 394 pairs of employees and their immediate supervisors working in the Information and Communication Technology (ICT) sector in three northern European countries, this study examined the effect of workplace moderators on the link between relational demography and supervisor ratings of performance. Directional age differences between superior…

  10. The Effects of Age at Arrival and Enclave Schools on the Academic Performance of Immigrant Children

    ERIC Educational Resources Information Center

    Cortes, Kalena E.

    2006-01-01

    This paper analyzes the relationship between age at arrival and immigrant-receiving high schools (i.e., enclave schools) on the academic performance of first- and second-generation immigrant children using data from the Children of Immigrants Longitudinal Study (CILS). The CILS survey was conducted in two major immigrant-receiving cities in the…

  11. Cognitive Functioning and Driving Simulator Performance in Middle-aged and Older Adults with HIV

    PubMed Central

    Vance, David E.; Fazeli, Pariya L.; Ball, David A.; Slater, Larry Z.; Ross, Lesley A.

    2014-01-01

    Nearly half of people living with HIV experience cognitive deficits that may impact instrumental activities of daily living. As the number of people aging with HIV increases, concerns mount that disease-related cognitive deficits may be compounded by age-related deficits, which may further compromise everyday functions such as driving. In this cross-sectional pilot study, during a 2.5-hour visit, 26 middle-aged and older adults (40+ years) were administered demographic, health, psychosocial, and driving habits questionnaires; cognitive assessments; and driving simulator tests. Although CD4+T lymphocyte count and viral load were unrelated to driving performance, older age was related to poorer driving. Furthermore, poorer visual speed of processing performance (i.e., Useful Field of View) was related to poorer driving performance (e.g., average gross reaction time). Mixed findings were observed between driving performance and cognitive function on self-reported driving habits of participants. Implications for these findings on nursing practice and research are posited. PMID:24513104

  12. The Mediating Effect of Age on the Relationship between Hyperactivity and Neuropsychological Test Performance.

    ERIC Educational Resources Information Center

    Massman, Paul J.; Nussbaum, Nancy L.

    The relationship between hyperactivity and neuropsychological test performance at different age levels was investigated with 90 children 6-8 years old and 92 children 9-12 years old. Subjects were administered a battery of neuropsychological tests, and a parent completed the Child Behavior Checklist (CBC). Young children demonstrated no…

  13. Interindividual Differences in Learning Performance: The Effects of Age, Intelligence, and Strategic Task Approach

    ERIC Educational Resources Information Center

    Kliegel, Matthias; Altgassen, Mareike

    2006-01-01

    The present study investigated fluid and crystallized intelligence as well as strategic task approaches as potential sources of age-related differences in adult learning performance. Therefore, 45 young and 45 old adults were asked to learn pictured objects. Overall, young participants outperformed old participants in this learning test. However,…

  14. Effects of Age of English Exposure, Current Input/Output, and Grade on Bilingual Language Performance

    ERIC Educational Resources Information Center

    Bedore, Lisa M.; Pena, Elizabeth D.; Griffin, Zenzi M.; Hixon, J. Gregory

    2016-01-01

    This study evaluates the effects of Age of Exposure to English (AoEE) and Current Input/Output on language performance in a cross-sectional sample of Spanish-English bilingual children. First- (N = 586) and third-graders (N = 298) who spanned a wide range of bilingual language experience participated. Parents and teachers provided information…

  15. Age, Gender, and Training in Children's Performance of Piaget's Horizontality Task.

    ERIC Educational Resources Information Center

    Parameswaran, Gowri

    2003-01-01

    Presents a study in which children (n=600), ages five to nine, completed Jean Piaget's horizontality task using a square water bottle. Finds a significant sex difference in the pretest performance of the horizontality task beginning with eight year olds. Includes references. (CMK)

  16. Relationship between the relative age effect and anthropometry, maturity and performance in young soccer players.

    PubMed

    Gil, Susana Maria; Badiola, Aduna; Bidaurrazaga-Letona, Iraia; Zabala-Lili, Jon; Gravina, Leyre; Santos-Concejero, Jordan; Lekue, Jose Antonio; Granados, Cristina

    2014-01-01

    The presence of the relative age effect (RAE) has been widely reported; however, its underlying causes have not yet been determined. With this in mind, the present study examined if anthropometry and performance were different amongst older and younger soccer players born in the same year. Eighty-eight young soccer players participated in the study (age 9.75 ± 0.30). Anthropometric measurements, physical tests (sprint, agility, endurance test, jump and hand dynamometry) and the estimation of the maturity status were carried out. Most players (65.9%) were born in the first half of the year. Older players were taller (P < 0.05), had longer legs (P < 0.01) and a larger fat-free mass (P < 0.05). Maturity offset was smaller in the older boys (P < 0.05); however, age at peak height velocity was similar. Older boys performed better in velocity and agility (P < 0.05) and particularly in the overall score of performance (P < 0.01). Stepwise regression analysis revealed that chronological age was the most important variable in the agility test and the overall score, after the skinfolds (negative effect). We report differences in anthropometry and physical performance amongst older and younger pre-pubertal soccer players. These differences may underlie the RAE.

  17. Does Relative Age Influence Motor Test Performance of Fourth Grade Pupils?

    ERIC Educational Resources Information Center

    Wattie, Nick; Tietjens, Maike; Schorer, Jörg; Ghanbari, Marie-Christine; Strauss, Bernd; Seidel, Ilka; Baker, Joseph

    2014-01-01

    The aim of the current study was to explore relative age's influence on physical and motor tests among fourth grade children (9 to 10 years) from Germany. Data from 1218 children (49% female) who had performed the German Motor Ability Test (Bös et al., 2009) were analysed. The test battery, which was comprised of physical and motor tests, included…

  18. The Effects of Person versus Performance Praise on Children's Motivation: Gender and Age as Moderating Factors

    ERIC Educational Resources Information Center

    Corpus, Jennifer Henderlong; Lepper, Mark R.

    2007-01-01

    Two studies were conducted to determine how gender and age moderate the long-term and post-failure motivational consequences of person versus performance praise. In Study 1, fourth- and fifth-grade students (n = 93) engaged in a puzzle task while receiving either no praise, person praise, product praise, or process praise. Following a subsequent…

  19. Functional performance of school children diagnosed with developmental delay up to two years of age

    PubMed Central

    Dornelas, Lílian de Fátima; Magalhães, Lívia de Castro

    2016-01-01

    Abstract Objective: To compare the functional performance of students diagnosed with developmental delay (DD) up to two years of age with peers exhibiting typical development. Methods: Cross-sectional study with functional performance assessment of children diagnosed with DD up to two years of age compared to those with typical development at seven to eight years of age. Each group consisted of 45 children, selected by non-random sampling, evaluated for motor skills, quality of home environment, school participation and performance. ANOVA and the Binomial test for two proportions were used to assess differences between groups. Results: The group with DD had lower motor skills when compared to the typical group. While 66.7% of children in the typical group showed adequate school participation, receiving aid in cognitive and behavioral tasks similar to that offered to other children at the same level, only 22.2% of children with DD showed the same performance. Although 53.3% of the children with DD achieved an academic performance expected for the school level, there were limitations in some activities. Only two indicators of family environment, diversity and activities with parents at home, showed statistically significant difference between the groups, with advantage being shown for the typical group. Conclusions: Children with DD have persistent difficulties at school age, with motor deficit, restrictions in school activity performance and low participation in the school context, as well as significantly lower functional performance when compared to children without DD. A systematic monitoring of this population is recommended to identify needs and minimize future problems. PMID:26553573

  20. Analysis of postural control and muscular performance in young and elderly women in different age groups

    PubMed Central

    Gomes, Matheus M.; Reis, Júlia G.; Carvalho, Regiane L.; Tanaka, Erika H.; Hyppolito, Miguel A.; Abreu, Daniela C. C.

    2015-01-01

    BACKGROUND: muscle strength and power are two factors affecting balance. The impact of muscle strength and power on postural control has not been fully explored among different age strata over sixty. OBJECTIVES: the aim of the present study was to assess the muscle strength and power of elderly women in different age groups and determine their correlation with postural control. METHOD: eighty women were divided into four groups: the young 18-30 age group (n=20); the 60-64 age group (n=20); the 65-69 age group (n=20); and the 70-74 age group (n=20). The participants underwent maximum strength (one repetition maximum or 1-RM) and muscle power tests to assess the knee extensor and flexor muscles at 40%, 70%, and 90% 1-RM intensity. The time required by participants to recover their balance after disturbing their base of support was also assessed. RESULTS: the elderly women in the 60-64, 65-69, and 70-74 age groups exhibited similar muscle strength, power, and postural control (p>0.05); however, these values were lower than those of the young group (p<0.05) as expected. There was a correlation between muscle strength and power and the postural control performance (p<0.05). CONCLUSION: despite the age difference, elderly women aged 60 to 74 years exhibited similar abilities to generate strength and power with their lower limbs, and this ability could be one factor that explains the similar postural control shown by these women. PMID:25651132

  1. Effectiveness and safety of outpatient pleurodesis in patients with recurrent malignant pleural effusion and low performance status

    PubMed Central

    Terra, Ricardo Mingarini; Teixeira, Lisete Ribeiro; Bibas, Benoit Jacques; Pego‐Fernandes, Paulo Manuel; Vargas, Francisco Suso; Jatene, Fabio Biscegli

    2011-01-01

    OBJECTIVES: To evaluate the effectiveness and safety of pleurodesis carried out entirely on an outpatient basis in patients with recurrent malignant pleural effusions and Karnofsky Performance Status scores ≤70. METHODS: This study was a prospective trial comprising patients with symptomatic recurrent malignant pleural effusion and Karnofsky Performance Status scores ≤70 but >30. All selected patients underwent pleural catheter placement (14 Fr) in an outpatient facility. When chest radiography revealed post‐drainage lung expansion of >90%, pleurodesis (3 g of talc) was performed. Catheters were maintained until the daily output was <100 mL/day. The patients were evaluated in the first month and every three months thereafter for fluid recurrence, the need for additional procedures, and complications. RESULTS: During the study period (January 2005 to July 2007), 64 patients (24 men, 40 women), with an average age of 61.4 years, underwent elective chest tube drainage. Primary sites of the underlying malignancy were breast (27), lung (22), and others (15). Sixty‐six pleural catheters were placed (bilaterally in 2 patients), and 52 talc pleurodesis procedures were performed. Fourteen patients had a trapped lung and were excluded from the trial. No complications were observed during catheter placement or pleurodesis. Post‐pleurodesis complications included catheter obstruction (4 patients) and empyema (1). The average drainage time was 9.9 days. The recurrence rate observed in patients that were alive 30 days after pleurodesis was 13.9% (5/36 patients). Six patients required additional procedures after the pleurodesis. The average survival time was 101 days. CONCLUSION: In this study, talc pleurodesis was safely performed in an outpatient setting with good efficacy and a reasonable complication rate, thereby avoiding hospital admission. PMID:21484035

  2. INTERACTIONS BETWEEN AGE AND MODERATE ALCOHOL EFFECTS ON SIMULATED DRIVING PERFORMANCE

    PubMed Central

    Sklar, Alfredo L.; Boissoneault, Jeff; Fillmore, Mark T.; Nixon, Sara Jo

    2013-01-01

    Rationale There is a substantial body of literature documenting the deleterious effects of both alcohol consumption and age on driving performance. There is, however, limited work examining the interaction of age and acute alcohol consumption. Objectives The current study was conducted to determine if moderate alcohol doses differentially affect the driving performance of older and younger adults. Methods Healthy older (55 – 70) and younger (25 – 35) adults were tested during a baseline session and again following consumption of one of three beverages (0.0% (placebo), 0.04% or 0.065% target breath alcohol concentration). Measures of driving precision and average speed were recorded. Results Older adults performed more poorly on precision driving measures and drove more slowly than younger adults at baseline. After controlling for baseline performance, interactions between alcohol and age were observed following beverage consumption on two measures of driving precision with older adults exhibiting greater impairment as a result of alcohol consumption. Conclusions These data provide evidence that older adults may be more susceptible to the effects of alcohol on certain measures of driving performance. An investigation of mechanisms accounting for alcohol’s effects on driving in older and younger adults is required. Further evaluation using more complex driving environments is needed to assess the real-world implication of this interaction. PMID:24030469

  3. Characterization and restoration of performance of {open_quotes}aged{close_quotes} radioiodine removing activated carbons

    SciTech Connect

    Freeman, W.P.

    1997-08-01

    The degradation of radioiodine removal performance for impregnated activated carbons because of ageing is well established. However, the causes for this degradation remain unclear. One theory is that this reduction in performance from the ageing process results from an oxidation of the surface of the carbon. Radioiodine removing activated carbons that failed radioiodine removal tests showed an oxidized surface that had become hydrophilic compared with new carbons. We attempted to restore the performance of these {open_quotes}failed{close_quotes} carbons with a combination of thermal and chemical treatment. The results of these investigations are presented and discussed with the view of extending the life of radioiodine removing activated carbons. 4 refs., 2 tabs.

  4. EFFECT OF ENGINE-BASED THERMAL AGING ON SURFACE MORPHOLOGY AND PERFORMANCE OF LEAN NOX TRAPS

    SciTech Connect

    Toops, Todd J; Bunting, Bruce G; Nguyen, Ke; Gopinath, Ajit

    2007-01-01

    A small single-cylinder diesel engine is used to thermally age model (Pt + Rh/Ba/{gamma}-Al{sub 2}O{sub 3}) lean NOx traps (LNTs) under lean/rich cycling at target temperatures of 600 C, 700 C, and 800 C. During an aging cycle, fuel is injected into the exhaust to achieve reproducible exotherms under lean and rich conditions with the average temperature approximating the target temperature. Aging is performed until the cycle-average NOx conversion measured at 400 C is approximately constant. Engine-based NOx conversion decreased by 42% after 60 cycles at 600 C, 36% after 76 cycles at 700 C and 57% after 46 cycles at 800 C. The catalyst samples were removed and characterized by XRD and using a microreactor that allowed controlled measurements of surface area, precious metal size, NOx storage, and reaction rates. Three aging mechanisms responsible for the deactivation of LNTs have been identified: (i) loss of dispersion of the precious metals, (ii) phase transitions in the washcoat materials, and (iii) loss of surface area of the storage component and support. These three mechanisms are accelerated when the aging temperature exceeds 850 C--the {gamma} to {delta} transition temperature of Al{sub 2}O{sub 3}. Normalization of rates of NO reacted at 400 C to total surface area demonstrates the biggest impact on performance stems from surface area losses rather than from precious metal sintering.

  5. Age-dependent and coordinated shift in performance between implicit and explicit skill learning

    PubMed Central

    Nemeth, Dezso; Janacsek, Karolina; Fiser, József

    2013-01-01

    It has been reported recently that while general sequence learning across ages conforms to the typical inverted-U shape pattern, with best performance in early adulthood, surprisingly, the basic ability of picking up in an implicit manner triplets that occur with high vs. low probability in the sequence is best before 12 years of age and it significantly weakens afterwards. Based on these findings, it has been hypothesized that the cognitively controlled processes coming online at around 12 are useful for more targeted explicit learning at the cost of becoming relatively less sensitive to raw probabilities of events. To test this hypothesis, we collected data in a sequence learning task using probabilistic sequences in five age groups from 11 to 39 years of age (N = 288), replicating the original implicit learning paradigm in an explicit task setting where subjects were guided to find repeating sequences. We found that in contrast to the implicit results, performance with the high- vs. low-probability triplets was at the same level in all age groups when subjects sought patterns in the sequence explicitly. Importantly, measurements of explicit knowledge about the identity of the sequences revealed a significant increase in ability to explicitly access the true sequences exactly around the age where the earlier study found the significant drop in ability to learn implicitly raw probabilities. These findings support the conjecture that the gradually increasing involvement of more complex internal models optimizes our skill learning abilities by compensating for the performance loss due to down-weighting the raw probabilities of the sensory input, while expanding our ability to acquire more sophisticated skills. PMID:24155717

  6. Effects of age and experience on reproductive performance of wood ducks

    SciTech Connect

    Hepp, G.R. ); Kennamer, R.A. )

    1993-10-01

    Data from a long-term study of Wood Ducks breeding in South Carolina were used to test whether reproductive performance was age specific and to evaluate several hypotheses proposed for age-specific variation. We used known-aged females from 1 through 5 yr of age. Yearling females initiated nests 11-19 d later than older females; heavier females, independent of age, nested earlier than lighter females. One-way analyses of covariance using female body mass and nesting date as covariates indicated that clutch size, mean egg mass, number of ducklings per nest, and the percentage of eggs hatching (hatching success) were independent of female age. Probability of nests producing at least one duckling (nest success) also was not related to female egg. We separately tested effects of breeding experience and female age class (yearling vs. adult) on reproductive performance. In the context of this study, females were considered as experienced if they previously were captured using nest boxes and inexperienced if there was no record of nest box use. Adult females with previous breeding experience initiated nests an average of 26 d earlier than adults without previous experience; body mass of experienced adults was greater than that of inexperienced adults. Adult females designated as [open quotes]inexperienced[close quotes] may have nested previously in natural cavities and were simply changing to nest boxes. Nest-site fidelity is known to affect nesting date, so we also compared nesting dates of inexperienced adults with a subset of of experienced females that changed nest sites.

  7. Influence of schooling and age on cognitive performance in healthy older adults.

    PubMed

    Bento-Torres, N V O; Bento-Torres, J; Tomás, A M; Costa, V O; Corrêa, P G R; Costa, C N M; Jardim, N Y V; Picanço-Diniz, C W

    2017-03-23

    Few studies have examined the influence of a low level of schooling on age-related cognitive decline in countries with wide social and economic inequalities by using the Cambridge Automated Neuropsychological Test Battery (CANTAB). The aim of the present study was to assess the influence of schooling on age-related cognitive decline using unbiased cognitive tests. CANTAB allows cognitive assessment across cultures and education levels with reduced interference of the examiner during data acquisition. Using two-way ANOVA, we assessed the influences of age and education on test scores of old adults (61-84 years of age). CANTAB tests included: Visual Sustained Attention, Reaction Time, Spatial Working Memory, Learning and Episodic Memory. All subjects had a minimum visual acuity of 20/30 (Snellen Test), no previous or current history of traumatic brain/head trauma, stroke, language impairment, chronic alcoholism, neurological diseases, memory problems or depressive symptoms, and normal scores on the Mini Mental State Examination (MMSE). Subjects were grouped according to education level (1 to 7 and ≥8 years of schooling) and age (60-69 and ≥70 years). Low schooling level was associated with significantly lower performance on visual sustained attention, learning and episodic memory, reaction time, and spatial working memory. Although reaction time was influenced by age, no significant results on post hoc analysis were detected. Our findings showed a significantly worse cognitive performance in volunteers with lower levels of schooling and suggested that formal education in early life must be included in the preventive public health agenda. In addition, we suggest that CANTAB may be useful to detect subtle cognitive changes in healthy aging.

  8. Working memory training and transfer in older adults: effects of age, baseline performance, and training gains.

    PubMed

    Zinke, Katharina; Zeintl, Melanie; Rose, Nathan S; Putzmann, Julia; Pydde, Andrea; Kliegel, Matthias

    2014-01-01

    Recent studies suggest that working memory training may benefit older adults; however, findings regarding training and transfer effects are mixed. The current study aimed to investigate the effects of a process-based training intervention in a diverse sample of older adults and explored possible moderators of training and transfer effects. For that purpose, 80 older adults (65-95 years) were assigned either to a training group that worked on visuospatial, verbal, and executive working memory tasks for 9 sessions over 3 weeks or to a control group. Performance on trained and transfer tasks was assessed in all participants before and after the training period, as well as at a 9-month follow-up. Analyses revealed significant training effects in all 3 training tasks in trained participants relative to controls, as well as near transfer to a verbal working memory task and far transfer to a fluid intelligence task. Encouragingly, all training effects and the transfer effect to verbal working memory were stable at the 9-month follow-up session. Further analyses revealed that training gains were predicted by baseline performance in training tasks and (to a lesser degree) by age. Gains in transfer tasks were predicted by age and by the amount of improvement in the trained tasks. These findings suggest that cognitive plasticity is preserved over a large range of old age and that even a rather short training regime can lead to (partly specific) training and transfer effects. However, baseline performance, age, and training gains moderate the amount of plasticity.

  9. Age effects on transfer index performance and executive control in baboons (Papio papio).

    PubMed

    Bonté, Elodie; Kemp, Caralyn; Fagot, Joël

    2014-01-01

    Reversal performance in the transfer index (TI) task is known to improve from prosimians to apes, suggesting that this task is a marker of cognitive evolution within the primate taxa (Rumbaugh, 1970). However, the cognitive processes recruited by this task remain unclear. In the present study, 19 socially-housed baboons (Papio papio) from 1.6 to 14.3 years of age were tested on a computerized version of the TI task, using an automated self-testing procedure. Age was a significant factor in the level of success, with the younger baboons outperforming the adults. The younger baboons learned the pre-reversal discrimination faster and improved their post-reversal performance more rapidly than adult baboons. As 17 of these baboons had already been tested in previous studies on inhibitory control and cognitive flexibility tasks, comparison across tasks provide indicators of the underlying cognitive processes. Age variations in performance were similar between the TI task and in an adaptation of the Wisconsin Card Sorting Task (WCST) measuring cognitive flexibility (Bonté et al., 2011). This contrasts previous results from a task requiring motor inhibitory control (Fagot et al., 2011). Therefore, these findings suggest that cognitive flexibility was a central component of the cognitive system that evolved within non-human primates. They also implicate a decline in executive control with age that begins during early adulthood in this baboon species.

  10. Mitochondrial DNA integrity changes with age but does not correlate with learning performance in honey bees.

    PubMed

    Hystad, E M; Amdam, G V; Eide, L

    2014-01-01

    The honey bee is a well-established model organism to study aging, learning and memory. Here, we used young and old forager honey bees to investigate whether age-related learning capacity correlates with mitochondrial function. The bees were selected for age and learning performance and mitochondrial function was evaluated by measuring mtDNA integrity, mtDNA copy number and mitochondrial gene expression. Quite unexpectedly, mtDNA from young bees showed more damage than mtDNA from older bees, but neither mtDNA integrity, nor mtDNA copy number nor mitochondrial gene expression correlated with learning performance. Although not statistically significant (p=0.07) the level of L-rRNA increased with age in good learners whereas it decreased in poor learners. Our results show that learning performance in honey bee does not correlate with absolute mitochondrial parameters like mtDNA damage, copy number or expression of mitochondrial genes, but may be associated with the ability to regulate mitochondrial activity.

  11. Aging Enhances Indirect Flight Muscle Fiber Performance yet Decreases Flight Ability in Drosophila

    SciTech Connect

    Miller, Mark S.; Lekkas, Panagiotis; Braddock, Joan M.; Farman, Gerrie P.; Ballif, Bryan A.; Irving, Thomas C.; Maughan, David W.; Vigoreaux, Jim O.

    2008-10-02

    We investigated the effects of aging on Drosophila melanogaster indirect flight muscle from the whole organism to the actomyosin cross-bridge. Median-aged (49-day-old) flies were flight impaired, had normal myofilament number and packing, barely longer sarcomeres, and slight mitochondrial deterioration compared with young (3-day-old) flies. Old (56-day-old) flies were unable to beat their wings, had deteriorated ultrastructure with severe mitochondrial damage, and their skinned fibers failed to activate with calcium. Small-amplitude sinusoidal length perturbation analysis showed median-aged indirect flight muscle fibers developed greater than twice the isometric force and power output of young fibers, yet cross-bridge kinetics were similar. Large increases in elastic and viscous moduli amplitude under active, passive, and rigor conditions suggest that median-aged fibers become stiffer longitudinally. Small-angle x-ray diffraction indicates that myosin heads move increasingly toward the thin filament with age, accounting for the increased transverse stiffness via cross-bridge formation. We propose that the observed protein composition changes in the connecting filaments, which anchor the thick filaments to the Z-disk, produce compensatory increases in longitudinal stiffness, isometric tension, power and actomyosin interaction in aging indirect flight muscle. We also speculate that a lack of MgATP due to damaged mitochondria accounts for the decreased flight performance.

  12. Impact of vocational interests, previous academic experience, gender and age on Situational Judgement Test performance.

    PubMed

    Schripsema, Nienke R; van Trigt, Anke M; Borleffs, Jan C C; Cohen-Schotanus, Janke

    2017-05-01

    Situational Judgement Tests (SJTs) are increasingly implemented in medical school admissions. In this paper, we investigate the effects of vocational interests, previous academic experience, gender and age on SJT performance. The SJT was part of the selection process for the Bachelor's degree programme in Medicine at University of Groningen, the Netherlands. All applicants for the academic year 2015-2016 were included and had to choose between learning communities Global Health (n = 126), Sustainable Care (n = 149), Intramural Care (n = 225), or Molecular Medicine (n = 116). This choice was used as a proxy for vocational interest. In addition, all graduate-entry applicants for academic year 2015-2016 (n = 213) were included to examine the effect of previous academic experience on performance. We used MANCOVA analyses with Bonferroni post hoc multiple comparisons tests for applicant performance on a six-scenario SJT. The MANCOVA analyses showed that for all scenarios, the independent variables were significantly related to performance (Pillai's Trace: 0.02-0.47, p < .01). Vocational interest was related to performance on three scenarios (p < .01). Graduate-entry applicants outperformed all other groups on three scenarios (p < .01) and at least one other group on the other three scenarios (p < .01). Female applicants outperformed male applicants on three scenarios (p < .01) and age was positively related to performance on two scenarios (p < .05). A good fit between applicants' vocational interests and SJT scenario was related to better performance, as was previous academic experience. Gender and age were related to performance on SJT scenarios in different settings. Especially the first effect might be helpful in selecting appropriate candidates for areas of health care in which more professionals are needed.

  13. Accuracy of emergency physician performed bedside ultrasound in determining gestational age in first trimester pregnancy

    PubMed Central

    2012-01-01

    Background Patient reported menstrual history, physician clinical evaluation, and ultrasonography are used to determine gestational age in the pregnant female. Previous studies have shown that pregnancy dating by last menstrual period (LMP) and physical examination findings can be inaccurate. An ultrasound performed in the radiology department is considered the standard for determining an accurate gestational age. The aim of this study is to determine the accuracy of emergency physician performed bedside ultrasound as an estimation of gestational age (EDUGA) as compared to the radiology department standard. Methods A prospective convenience sample of ED patients presenting in the first trimester of pregnancy (based upon self-reported LMP) regardless of their presenting complaint were enrolled. EDUGA was compared to gestational age estimated by ultrasound performed in the department of radiology (RGA) as the gold standard. Pearson’s product moment correlation coefficient was used to determine the correlation between EDUGA compared to RGA. Results Sixty-eight pregnant patients presumed to be in the 1st trimester of pregnancy based upon self-reported LMP consented to enrollment. When excluding the cases with no fetal pole, the median discrepancy of EDUGA versus RGA was 2 days (interquartile range (IQR) 1 to 3.25). The correlation coefficient of EDUGA with RGA was 0.978. When including the six cases without a fetal pole in the data analysis, the median discrepancy of EDUGA compared with RGA was 3 days (IQR 1 to 4). The correlation coefficient of EDUGA with RGA was 0.945. Conclusion Based on our comparison of EDUGA to RGA in patients presenting to the ED in the first trimester of pregnancy, we conclude that emergency physicians are capable of accurately performing this measurement. Emergency physicians should consider using ultrasound to estimate gestational age as it may be useful for the future care of that pregnant patient. PMID:23216683

  14. Performance of an age series of Alnus-cardamom plantations in the Sikkim Himalaya: nutrient dynamics.

    PubMed

    Sharma, G; Sharma, R; Sharma, E; Singh, K K

    2002-03-01

    Nutrient cycling, nutrient use efficiency and nitrogen fixation in an age series of Alnus-cardamom plantations were studied in the eastern Himalaya. The impact of stand age (5, 10, 15, 20, 30 and 40 years) on the nutrient dynamics of mixtures of N2-fixing (Alnus nepalensis) and non-N2-fixing (large cardamom) plants was assessed. Foliar nutrient concentrations of Alnus decreased with advancing age groups of plantations and showed an inverse relationship with stand age. Annual N fixation increased from the 5-year-old stand (52 kg ha(-1)), peaking in the 15-year-old stand (155 kg ha(-1)) and then decreased with increasing plantation age. Nitrogen and phosphorus uptake was lowest in the 40-year-old stand, and highest in the 15- and 5-year-old stand, respectively. Nutrient storage in understorey cardamom was very high: up to 31 % N and 59 % P of the stand total in the 15-year-old stand. Nutrient use efficiency was higher (with faster turnover times) in younger stands and decreased (with slower turnover times) in older plantations. Nitrogen retranslocation showed a strong positive relationship with stand age, while that of P was inversely related to stand age. Nutrient standing stock, uptake and return were also highest in the 15-year-old stand. Nitrogen and P cycling in Alnus-cardamom plantations was functionally balanced. Nutrient cycling and dynamics indicated that Alnus-cardamom plantations performed sustainably up to 15-20 years. The management practice should be altered to incorporate replantation after this age.

  15. Mechanisms underlying age- and performance-related differences in working memory.

    PubMed

    Daffner, Kirk R; Chong, Hyemi; Sun, Xue; Tarbi, Elise C; Riis, Jenna L; McGinnis, Scott M; Holcomb, Phillip J

    2011-06-01

    This study took advantage of the subsecond temporal resolution of ERPs to investigate mechanisms underlying age- and performance-related differences in working memory. Young and old subjects participated in a verbal n-back task with three levels of difficulty. Each group was divided into high and low performers based on accuracy under the 2-back condition. Both old subjects and low-performing young subjects exhibited impairments in preliminary mismatch/match detection operations (indexed by the anterior N2 component). This may have undermined the quality of information available for the subsequent decision-making process (indexed by the P3 component), necessitating the appropriation of more resources. Additional anterior and right hemisphere activity was recruited by old subjects. Neural efficiency and the capacity to allocate more resources to decision-making differed between high and low performers in both age groups. Under low demand conditions, high performers executed the task utilizing fewer resources than low performers (indexed by the P3 amplitude). As task requirements increased, high-performing young and old subjects were able to appropriate additional resources to decision-making, whereas their low-performing counterparts allocated fewer resources. Higher task demands increased utilization of processing capacity for operations other than decision-making (e.g., sustained attention) that depend upon a shared pool of limited resources. As demands increased, all groups allocated additional resources to the process of sustaining attention (indexed by the posterior slow wave). Demands appeared to have exceeded capacity in low performers, leading to a reduction of resources available to the decision-making process, which likely contributed to a decline in performance.

  16. Academic performance and intelligence scores of primary school-aged children with sickle cell anemia.

    PubMed

    Ezenwosu, Osita; Emodi, Ifeoma; Ikefuna, Anthony; Chukwu, Barth

    2013-11-01

    Children with sickle cell anemia (SCA) are faced with complications which may interfere with their educational activities including academic performance. Reports on their academic performance are mainly from developed countries and the results have been inconsistent. This study aimed to determine the academic performance of primary school-aged children with SCA in Nigeria and compare findings with a group of controls. Ninety children with SCA aged 5-11 years were consecutively recruited at the SCA clinic of UNTH Enugu and their age- and sex-matched normal classmates were enrolled as controls. Academic performance of the children with SCA was studied using the overall scores achieved in the three term examinations in the preceding academic year (2009/2010), while their intelligence quotient (IQ) was determined using the Draw-A-Person Test. The findings were compared with that of 90 controls. The mean overall academic score of the children with SCA of 62.71 ± 19.43% was similar to 67.47 ± 16.42% in the controls (P = .077). However, a significantly higher number of children with SCA (32.2% vs. 16.7% of the controls; P = .015) scored below 50%, thus, had poor performance. The mean IQ of the subjects (91.41 ±16.61%) was similar to that of the controls (95.56 ±17.31%, P = .103). However, more SCA patients had lower IQ scores than controls though not statistically significant (P = 0.083). The overall academic performance of children with SCA, therefore, compares favorably with that of controls although there is a higher prevalence of poor performance among them.

  17. Aging and work: how do SOC strategies contribute to job performance across adulthood?

    PubMed

    Yeung, Dannii Y; Fung, Helene H

    2009-12-01

    The authors examined the impacts of selection, optimization, and compensation (SOC) strategies-elective selection, loss-based selection, optimization, and compensation-on job performance across adulthood. A cross-sectional survey (Study 1, N=355) and a 5-day experience sampling study (Study 2, N=87) were conducted to assess Chinese insurance sales workers' global and momentary employment of SOC strategies at work and compare the effectiveness of these strategies in predicting their job performance. Study 1 revealed that the use of compensation predicted higher performance maintenance among older workers, whereas the use of elective selection contributed positively to sales productivity for both age groups, with stronger association for younger workers. Study 2 demonstrated that the positive impact of SOC strategies on global and momentary measures of job performance differed across tasks with various difficulty levels. When the task was perceived as highly difficult, older workers' greater use of elective selection predicted higher self-rated task performance; however, the positive association was weaker among younger workers. Older workers' greater use of the 4 SOC strategies was positively associated with sales increases when the task was not difficult or moderately difficult, yet the relationship was negative when the task was highly difficult. A reverse pattern was observed among younger workers. This article contributes to the understanding of working adults' psychological adaptation to the process of aging and reveals the moderating role of task difficulty on the association between SOC strategies and performance outcomes.

  18. Evaluation of Thermal Oxidative Aging Effect on the Rheological Performance of Modified Asphalt Binders

    NASA Astrophysics Data System (ADS)

    Zhu, Cheng

    Modified asphalt binder, which is combined by base binder and additive modifier, has been implemented in pavement industry for more than 30 years. Recently, the oxidative aging mechanism of asphalt binder has been studied for several decades, and appreciable finding results of asphalt binder aging mechanism were achieved from the chemistry and rheological performance aspects. However, most of these studies were conducted with neat binders, the research of aging mechanism of modified asphalt binder was limited. Nowadays, it is still highly necessary to clarify how the asphalt binder aging happens with the modified asphalt binder, what is the effect of the different modifiers (additives) on the binder aging process, how the rheological performance changes under the thermal oxidative aging conditions and so on. The objective of this study was to investigate the effect of isothermal oxidative aging conditions on the rheological performance change of the modified and controlled asphalt binders. There were totally 14 different sorts of asphalt binders had been aged in the PAV pans in the air-force drafted ovens at 50°C, 60°C and 85°C for 0.5 day to 240 days. The Fourier-Transform Infrared Spectroscopy (FT-IR) and Dynamic Shear Rheometer (DSR) were used to perform the experiments. The analysis of rheological indices (Low shear viscosity-LSV, Crossover modulus-G*c, Glover-Rowe Parameter-G-R, DSR function-DSR Fn) as a function of carbonyl area (CA) was conducted. With the SBS modification, both of the hardening susceptibility of the rheological index-LSV and G-R decreases compared with the corresponding base binder. The TR increased the hardening susceptibility of all the rheological indexes. While for the G*c, SBS increases the slope of the most modified asphalt binders except A and B_TR_X series binders. The multiple linear regression statistical analysis results indicate that the oxidative aging conditions play an important role on the CA, and rheological performance

  19. Age-related declines in car following performance under simulated fog conditions

    PubMed Central

    Ni, Rui; Kang, Julie J.; Andersen, George J.

    2010-01-01

    The present study examined age-related differences in car following performance when contrast of the driving scene was reduced by simulated fog. Older (mean age of 72.6) and younger (mean age of 21.1) drivers were presented with a car following scenario in a simulator in which a lead vehicle (LV) varied speed according to a sum of three sine wave functions. Drivers were shown an initial following distance of 18m and were asked to maintain headway distance by controlling speed to match changes in LV speed. Five simulated fog conditions were examined ranging from a no fog condition (contrast of 0.55) to a high fog condition (contrast of 0.03). Average LV speed varied across trials (40, 60, or 80 km/h). The results indicated age-related declines in car following performance for both headway distance and RMS (root mean square) error in matching speed. The greatest decline occurred at moderate speeds under the highest fog density condition, with older drivers maintaining a headway distance that was 21% closer than younger drivers. At higher speeds older drivers maintained a greater headway distance than younger drivers. These results suggest that older drivers may be at greater risk for a collision under high fog density and moderate speeds. PMID:20380908

  20. Anthropometric, Physical, and Age Differences by the Player Position and the Performance Level in Volleyball

    PubMed Central

    Palao, José M.; Manzanares, Policarpo; Valadés, David

    2014-01-01

    The purpose of this paper was to study the ranges in height, weight, age, spike reach, and block reach of volleyball players in relation to the player position and the level of their respective teams in peak performance. The analysed sample included 1454 male and 1452 female players who participated in the volleyball competitions of the Olympic Games and World Championships in the 2000–2012 period. A descriptive, correlational, and longitudinal design was used. The variables studied were: the player position, body height, weight, body mass index, spike reach, block reach, age, and team level. The results show differences between body height, spike and block reaches, and the age of the players by their position. These differences are related to the needs of the different positions with regard to the actions they execute. Middle-blockers, outside-hitters, and opposites have the characteristics that are most suitable for blocking and spiking, and the setters and liberos appear to have characteristics conducive to setting and receiving as well as digging, respectively. The differences found in the studied variables with regard to the playing position are related to players’ needs regarding the actions they perform. Player’s age was a variable that differentiated first teams at this level of competition for males, and physical capacities (body height, weight, spike reach, and block reach) were variables that differentiated first teams at this level of competition for females. PMID:25713683

  1. Age-related declines in car following performance under simulated fog conditions.

    PubMed

    Ni, Rui; Kang, Julie J; Andersen, George J

    2010-05-01

    The present study examined age-related differences in car following performance when contrast of the driving scene was reduced by simulated fog. Older (mean age of 72.6) and younger (mean age of 21.1) drivers were presented with a car following scenario in a simulator in which a lead vehicle (LV) varied speed according to a sum of three sine wave functions. Drivers were shown an initial following distance of 18 m and were asked to maintain headway distance by controlling speed to match changes in LV speed. Five simulated fog conditions were examined ranging from a no fog condition (contrast of 0.55) to a high fog condition (contrast of 0.03). Average LV speed varied across trials (40, 60, or 80 km/h). The results indicated age-related declines in car following performance for both headway distance and RMS (root mean square) error in matching speed. The greatest decline occurred at moderate speeds under the highest fog density condition, with older drivers maintaining a headway distance that was 21% closer than younger drivers. At higher speeds older drivers maintained a greater headway distance than younger drivers. These results suggest that older drivers may be at greater risk for a collision under high fog density and moderate speeds.

  2. The electrical performance of polymeric insulating materials under accelerated aging in a fog chamber

    SciTech Connect

    Gorur, R.S.; Cherney, E.A.; Hackam, R. ); Orbeck, T. )

    1988-07-01

    A comparative study of the ac (60 Hz) surface aging in a fog chamber is reported on cylindrical rod samples of high temperature vulcanized (HTV) silicone rubber and ethylene propylene diene monomer (EPDM) rubber containing various amounts of alumina trihydrate (ATH) and/or silica fillers. In low conductivity (250 ..mu..S/cm) fog, silicone rubber performed better than EPDM samples whereas in high conductivity (1000 ..mu..S/cm) fog, the order of performance was reversed. The mechanisms by which fillers impart tracking and erosion resistance to materials is discussed as influenced by the experimental conditions of the accelerated aging tests. Surface studies by ESCA (Electron Spectroscopy for Chemical Analysis) demonstrate that the hydrophobicity of silicone rubber, despite the accumulation of surface contamination, can be attributed to migration of low molecular weight polymer chains and/or mobile fluids, such as silicone oil.

  3. Neural changes associated with semantic processing in healthy aging despite intact behavioral performance.

    PubMed

    Lacombe, Jacinthe; Jolicoeur, Pierre; Grimault, Stephan; Pineault, Jessica; Joubert, Sven

    2015-10-01

    Semantic memory recruits an extensive neural network including the left inferior prefrontal cortex (IPC) and the left temporoparietal region, which are involved in semantic control processes, as well as the anterior temporal lobe region (ATL) which is considered to be involved in processing semantic information at a central level. However, little is known about the underlying neuronal integrity of the semantic network in normal aging. Young and older healthy adults carried out a semantic judgment task while their cortical activity was recorded using magnetoencephalography (MEG). Despite equivalent behavioral performance, young adults activated the left IPC to a greater extent than older adults, while the latter group recruited the temporoparietal region bilaterally and the left ATL to a greater extent than younger adults. Results indicate that significant neuronal changes occur in normal aging, mainly in regions underlying semantic control processes, despite an apparent stability in performance at the behavioral level.

  4. Social-Economic Status and Cognitive Performance among Chinese Aged 50 Years and Older

    PubMed Central

    Wu, Fan; Guo, Yanfei; Zheng, Yang; Ma, Wenjun; Kowal, Paul; Chatterji, Somnath; Wang, Ling

    2016-01-01

    Background Numerous population-based studies have suggested that socio-economic status (SES) is associated with cognitive performance, but few nationally representative epidemiological studies on cognitive performance with a large sample of older adults are available in China. And many studies explore the factors associated with cognitive performance, mainly focusing on individual level and more rarely on multiple levels that include the individual and community. Methods This study uses SAGE-China Wave 1 data which consisted of 13,157 adults aged 50 years and older to explore socioeconomic inequalities in the cognitive performance from a multilevel perspective (individual and community levels). The overall cognition score was based on the seven separate components of the cognition tests, including the four verbal recall trials, the verbal fluency test, the forward digit span test and the backward digit span test. Factor analysis was applied to evaluate and generate a single overall score. A two-level hierarchical linear model was used to evaluate the association between SES at these two levels and the overall cognition score adjusted for age, sex and marital status. Results At individual level, years of education was significantly associated with overall cognition score for both urban and rural dwellers. At the community level, a positive association was obtained between median household income and median years of education and overall cognition score among urban participants. Conclusion A significant association between SES at both individual-level and community-level (only for urban area) and cognitive performance were found in this study of a national sample of 13,157 Chinese aged 50 years and older, even after adjusting for demographic characteristics. Identifying community-based SES variables that are associated with cognitive performance in the older population provides further evidence for the need to address community characteristics associated with

  5. Basketball Performance Is Related to Maturity and Relative Age in Elite Adolescent Players.

    PubMed

    Torres-Unda, Jon; Zarrazquin, Idoia; Gravina, Leyre; Zubero, Jaime; Seco, Jesús; Gil, Susana M; Gil, Javier; Irazusta, Jon

    2016-05-01

    During a national championship, the anthropometric, physiological, and maturation characteristics of 13- to 14-year-old players of elite basketball teams and their association with sport performance were analyzed. Body parameters (weight, height, skinfold thicknesses, and lengths) were measured and physiological capacities assessed by sprint (20 m) and jump tests (i.e., countermovement jump with arm swing). Chronological age (CA) and maturity offset (years from age at peak height velocity; YAPHV) were calculated, and then predicted age at peak height velocity, as the difference between CA and YAPHV. Game performance was assessed with point averages and the performance index rating (PIR). The birth-date distribution of players was biased, those born early in the selection year outnumbering those born later. Anthropometric analysis indicated that players who performed better had longer body lengths. Physiological testing showed that semi-finalists had better sprint performance than quarter-finalists and those players with greater jump capacity scored more points. Early maturation and advanced maturity status were also associated with better PIR and scored points per game. Multiple blockwise regression analysis showed that, among the factors analyzed, YAPHV was the best predictor of basketball performance. In conclusion, around puberty, physical and physiological parameters associated with maturity and CA are important in determining the success of elite basketball players. Consequently, boys who are born in the second half of the year and/or late maturing tend to be marginalized or totally excluded, and not given the chance to play under equal conditions; their careers may then be held back by the relative disadvantage associated with inexperience.

  6. Performance testing of aged hydrogen getters against criteria for interim safe storage of plutonium bearing materials.

    SciTech Connect

    Shepodd, Timothy J.; Nissen, April; Buffleben, George M.

    2006-01-01

    Hydrogen getters were tested for use in storage of plutonium-bearing materials in accordance with DOE's Criteria for Interim Safe Storage of Plutonium Bearing Materials. The hydrogen getter HITOP was aged for 3 months at 70 C and tested under both recombination and hydrogenation conditions at 20 and 70 C; partially saturated and irradiated aged getter samples were also tested. The recombination reaction was found to be very fast and well above the required rate of 45 std. cc H2h. The gettering reaction, which is planned as the backup reaction in this deployment, is slower and may not meet the requirements alone. Pressure drop measurements and {sup 1}H NMR analyses support these conclusions. Although the experimental conditions do not exactly replicate the deployment conditions, the results of our conservative experiments are clear: the aged getter shows sufficient reactivity to maintain hydrogen concentrations below the flammability limit, between the minimum and maximum deployment temperatures, for three months. The flammability risk is further reduced by the removal of oxygen through the recombination reaction. Neither radiation exposure nor thermal aging sufficiently degrades the getter to be a concern. Future testing to evaluate performance for longer aging periods is in progress.

  7. Variability in Wechsler Adult Intelligence Scale-IV subtest performance across age.

    PubMed

    Wisdom, Nick M; Mignogna, Joseph; Collins, Robert L

    2012-06-01

    Normal Wechsler Adult Intelligence Scale (WAIS)-IV performance relative to average normative scores alone can be an oversimplification as this fails to recognize disparate subtest heterogeneity that occurs with increasing age. The purpose of the present study is to characterize the patterns of raw score change and associated variability on WAIS-IV subtests across age groupings. Raw WAIS-IV subtest means and standard deviations for each age group were tabulated from the WAIS-IV normative manual along with the coefficient of variation (CV), a measure of score dispersion calculated by dividing the standard deviation by the mean and multiplying by 100. The CV further informs the magnitude of variability represented by each standard deviation. Raw mean scores predictably decreased across age groups. Increased variability was noted in Perceptual Reasoning and Processing Speed Index subtests, as Block Design, Matrix Reasoning, Picture Completion, Symbol Search, and Coding had CV percentage increases ranging from 56% to 98%. In contrast, Working Memory and Verbal Comprehension subtests were more homogeneous with Digit Span, Comprehension, Information, and Similarities percentage of the mean increases ranging from 32% to 43%. Little change in the CV was noted on Cancellation, Arithmetic, Letter/Number Sequencing, Figure Weights, Visual Puzzles, and Vocabulary subtests (<14%). A thorough understanding of age-related subtest variability will help to identify test limitations as well as further our understanding of cognitive domains which remain relatively steady versus those which steadily decline.

  8. Impact of sex and age on the performance of FINDRISC: the HUNT Study in Norway

    PubMed Central

    Midthjell, Kristian; Holmen, Jostein; Tuomilehto, Jaakko; Carlsen, Sven M; Shaw, Jonathan; Åsvold, Bjørn O

    2016-01-01

    Objective The Finnish Diabetes Risk Score (FINDRISC) is recommended as a screening tool for diabetes risk. However, there is a lack of well-powered studies examining the performance of FINDRISC by sex and age. We aim to estimate, by sex and age, the prevalence of elevated FINDRISC and positive predictive value (PPV) of FINDRISC for identifying impaired glucose metabolism (IGM) in a general Norwegian population. Research design and methods We estimated the prevalence of elevated FINDRISC (≥15) among 47 694 adults in the third survey of the Nord-Trøndelag Health Study (HUNT3, 2006–08). Among 2559 participants who participated in oral glucose tolerance testing, we estimated the PPV of elevated FINDRISC for identifying unknown prevalent diabetes and other forms of IGM. Results The prevalence of elevated FINDRISC was 12.1% in women, 9.6% in men, and increased from 1.5% at age 20–39 to 25.1% at age 70–79 years. The PPVs of elevated FINDRISC were 9.8% for diabetes, 16.9% for impaired glucose tolerance, 8.2% for impaired fasting glucose, and 34.9% for any form of IGM. The PPV for IGM was lower in women (31.2%) than in men (40.4%), and increased from 19.1% at age 20–39 to 55.5% at age ≥80 years. Conclusions FINDRISC identified more women than men as high-risk individuals for diabetes. FINDRISC had a high PPV for detecting prevalent IGM, and the PPV was higher in men than in women and in the older individuals. Our data indicate that the impact of sex and age on diabetes risk is not fully captured by FINDRISC, and that refinements to it might improve diabetes prediction. PMID:27403326

  9. Energy balance, metabolism, hydration, and performance during strenuous hill walking: the effect of age.

    PubMed

    Ainslie, P N; Campbell, I T; Frayn, K N; Humphreys, S M; MacLaren, D P M; Reilly, T; Westerterp, K R

    2002-08-01

    We aimed to examine the effect of age on energy balance, metabolism, hydration, and performance during 10 days of strenuous hill walking. Seventeen male subjects were divided into two groups according to their age. The nine subjects in group 1 constituted the younger group (age 24 +/- 3 yr), whereas eight older subjects were in group 2 (age 56 +/- 3 yr). Both groups completed 10 consecutive days of high-intensity hill walking. Mean (range) daily walking distances and ascent were 21 km (10-35 km) and 1,160 m (800-2,540 m), respectively. Energy intake was calculated from weighed food intake, and energy expenditure was measured by the doubly labeled water method. Blood and urine were sampled on alternative days to determine any changes in metabolism and hydration during the 10 days. Subjects also completed a battery of tests that included muscular strength (handgrip), jump performance, cognitive processing time, and flexibility. The younger group remained hydrated, whereas the older group became progressively dehydrated, indicated by a near twofold increase in urine osmolality concentration on day 11. This increased urine osmolality in the older group was highly correlated with impairment in vertical-jump performance (r = -0.86; P < 0.05) and decreased cognitive processing time (r = 0.79; P < 0.05). Despite energy expenditure of approximately 21 MJ/day, body mass was well maintained in both groups. Both groups displayed a marked increase in fat mobilization, reflected in significantly lowered prewalk insulin concentrations and elevated postwalk glycerol and nonesterified fatty acid concentrations. Despite the dehydration and impaired performance in the older group, blood glucose concentrations were well maintained in both groups, probably mediated via the increased mobilization of fat.

  10. Static stretching does not impair performance in active middle-aged adults.

    PubMed

    Handrakis, John P; Southard, Veronica N; Abreu, Jairo M; Aloisa, Mariella; Doyen, Mellissa R; Echevarria, Licet M; Hwang, Hyun; Samuels, Christine; Venegas, Steven A; Douris, Peter C

    2010-03-01

    Recent investigations with young, healthy adult subjects suggest that static stretching before activity decreases performance and should, therefore, be avoided. The purpose of this study was to assess the effects of an acute static stretching protocol on balance and jump/hop performance in active middle-aged adults. Ten subjects (6 men and 4 women aged 40-60 yr) from a martial arts school volunteered to take part in this research study. This was a repeated measures design. Subjects who stretched for 10 minutes using a 30-second hold during 1 session sat quietly for 10 minutes during the alternate session. Sessions were randomly assigned. The following dependent variables were compared: Dynamic Stability Index (DSI) for single-leg dynamic balance (smaller DSI = improved balance); distances for broad jump, single hop, triple hop, and crossover hop; elapsed time for a 6-m timed hop. Group means for balance were significantly different between the stretch and no-stretch conditions (3.5 +/- 0.7 vs. 4.3 +/- 1.4 DSI, respectively; p < 0.05). No significant differences were found between the group means of the stretch and no-stretch conditions for the dependent measures of broad jump, single hop, triple hop, crossover hop, and 6-m timed hop performance. Ten minutes of acute static stretching enhances dynamic balance and does not affect jump/hop performance in active middle-aged adults. Static stretching should be included before competition and before exercise in fitness programs of active middle-aged adults.

  11. Age-related differences in performance and stimulus processing in dual task situation.

    PubMed

    Hahn, Melanie; Wild-Wall, Nele; Falkenstein, Michael

    2011-09-26

    Competition for limited processing resources is most critical in dual-tasks which incorporate cognitive and motor demands. Performance is usually diminished with increasing age in such tasks. This decline is relevant for activities in real life like driving. In the present study we aim to examine if there are age-related differences in stimulus processing in a dual-task and if these differences have an impact on performance of a driving-like tracking task. Young and older participants performed a dual-task consisting of a tracking task and a visual attention task. Alongside, the EEG was recorded for calculating the P300 (P3) of the event-related potential as a reflection of controlled stimulus processing. In the visual attention task older vs. young participants showed more misses and false alarms. For young participants the P3 shows an expected pattern of higher amplitudes for relevant compared to irrelevant stimuli. This was not found for the older participants. A general age-related decline in tracking performance was relatively more pronounced if a secondary motor response was required in the visual attention task and also after irrelevant stimuli. The results suggest that older compared to young participants had greater difficulties to differentiate between relevant and irrelevant stimuli in a dual-task situation as they probably apply comparable attentional resources to all stimuli. This may also explain the higher error rates. These results have important implications for the understanding of age-related stimulus processing in dual and multi task situations in real life as for instance driving.

  12. Altered left ventricular performance in aging physically active mice with an ankle sprain injury.

    PubMed

    Turner, Michael J; Guderian, Sophie; Wikstrom, Erik A; Huot, Joshua R; Peck, Bailey D; Arthur, Susan T; Marino, Joseph S; Hubbard-Turner, Tricia

    2016-02-01

    We assessed the impact of differing physical activity levels throughout the lifespan, using a musculoskeletal injury model, on the age-related changes in left ventricular (LV) parameters in active mice. Forty male mice (CBA/J) were randomly placed into one of three running wheel groups (transected CFL group, transected ATFL/CFL group, SHAM group) or a SHAM Sedentary group (SHAMSED). Before surgery and every 6 weeks after surgery, LV parameters were measured under 2.5 % isoflurane inhalation. Group effects for daily distance run was significantly greater for the SHAM and lesser for the ATLF/CFL mice (p = 0.013) with distance run decreasing with age for all mice (p < 0.0001). Beginning at 6 months of age, interaction (group × age) was noted with LV posterior wall thickness-to-radius ratios (h/r) where h/r increased with age in the ATFL/CFL and SHAMSED mice while the SHAM and CFL mice exhibited decreased h/r with age (p = 0.0002). Passive filling velocity (E wave) was significantly greater in the SHAM mice and lowest for the ATFL/CFL and SHAMSED mice (p < 0.0001) beginning at 9 months of age. Active filling velocity (A wave) was not different between groups (p = 0.10). Passive-to-active filling velocity ratio (E/A ratio) was different between groups (p < 0.0001), with higher ratios for the SHAM mice and lower ratios for the ATFL/CFL and SHAMSED mice in response to physical activity beginning at 9 months of age. Passive-to-active filling velocity ratio decreased with age (p < 0.0001). Regular physical activity throughout the lifespan improved LV structure, passive filling velocity, and E/A ratio by 6 to 9 months of age and attenuated any negative alterations throughout the second half of life. The diastolic filling differences were found to be significantly related to the amount of activity performed by 9 months and at the end of the lifespan.

  13. Gait Velocity Is an Indicator of Cognitive Performance in Healthy Middle-Aged Adults

    PubMed Central

    Jabourian, Artin; Lancrenon, Sylvie; Delva, Catherine; Perreve-Genet, Alain; Lablanchy, Jean-Pierre; Jabourian, Maritza

    2014-01-01

    Psychomotor retardation, especially motor and cognitive slowing down, has been described many times in the elderly but to our knowledge, has never been examined in healthy middle-aged adults. The present study explores whether walking time may provide an early signal of cognitive performance, using 266 healthy adults ([18–65] years old, mean age: 45.7±12.9 years) who were also subdivided in 2 groups: under or over 50. Walking time (50 meters) and cognitive performances (mini-mental state examination, Benton Visual Retention Test and Rey Complex Figure) were assessed; total psychometric score was the sum of individual test scores. Analyses were controlled for age, gender, education level, height and weight. The mean psychometric scores were within the normal range. A substantial proportion of subjects exhibited low performance in some aspects of visuospatial memory, particularly in the older subset. In the total population, walking time was negatively correlated with all cognitive tests, particularly to total psychometric score (R = −0.817, p<0.0001); the unique contribution of walking time on all cognitive scores was very high (delta R-squared = 0.496). In the older subset, performances on walk and cognition were lower than in the younger subset. Total psychometric score showed the strongest correlation with walking time in the older subset (R = −0.867; p<0.001). In all subsets, walking time was the main explanatory variable of the total psychometric score (delta R-squared: ≤ 49 = 0.361; ≥50 = 0.613). These findings indicate that i) a significant proportion of adults without cognitive complaints exhibit low cognitive performance including visuospatial memory and longer walking time, ii) cognitive functioning is strongly correlated to walking time in healthy middle-aged adults, iii) gait velocity (GV) could be an indicator of cognitive performance in some important cognitive domains. These results warrant further investigation because

  14. Preserved Discrimination Performance and Neural Processing during Crossmodal Attention in Aging

    PubMed Central

    Mishra, Jyoti; Gazzaley, Adam

    2013-01-01

    In a recent study in younger adults (19-29 year olds) we showed evidence that distributed audiovisual attention resulted in improved discrimination performance for audiovisual stimuli compared to focused visual attention. Here, we extend our findings to healthy older adults (60-90 year olds), showing that performance benefits of distributed audiovisual attention in this population match those of younger adults. Specifically, improved performance was revealed in faster response times for semantically congruent audiovisual stimuli during distributed relative to focused visual attention, without any differences in accuracy. For semantically incongruent stimuli, discrimination accuracy was significantly improved during distributed relative to focused attention. Furthermore, event-related neural processing showed intact crossmodal integration in higher performing older adults similar to younger adults. Thus, there was insufficient evidence to support an age-related deficit in crossmodal attention. PMID:24278464

  15. ERP correlates of item recognition memory: effects of age and performance.

    PubMed

    Wolk, David A; Sen, N Mandu; Chong, Hyemi; Riis, Jenna L; McGinnis, Scott M; Holcomb, Phillip J; Daffner, Kirk R

    2009-01-23

    Decline in episodic memory is a common feature of healthy aging. Event-related potential (ERP) studies in young adults have consistently reported several modulations thought to index memory retrieval processes, but relatively limited work has explored the impact of aging on them. Further, work with functional imaging has demonstrated differential neural recruitment in elderly subjects depending on their level of cognitive performance which may reflect compensatory or, alternatively, inefficient processing. In the present study we examined the effect of aging and level of performance on both early (FN400, LPC) and later [late frontal effect (LFE)] ERP indices of recognition memory. We found that the FN400 and LPC were absent or attenuated in the older group relative to young adults, but that the LFE was actually increased, analogous to findings in the functional imaging literature. Additionally, the latter effect was most prominent in the poorer performing older participants. These findings suggest that weak memory retrieval supported by earlier ERP modulations, may lead to an enhanced LFE in the service of additional retrieval attempts.

  16. Effects of Resveratrol Supplementation and Exercise Training on Exercise Performance in Middle-Aged Mice.

    PubMed

    Kan, Nai-Wen; Ho, Chin-Shan; Chiu, Yen-Shuo; Huang, Wen-Ching; Chen, Pei-Yu; Tung, Yu-Tang; Huang, Chi-Chang

    2016-05-18

    Resveratrol (RES) has antioxidative, anti-inflammatory, anticancer, antidiabetic, antiasthmatic, antalgic, and anti-fatigue activities. Exercise training (ET) improves frailty resulting from aging. This study evaluated the effects of a combination of RES supplementation and ET on the exercise performance of aged mice. C57BL/6J mice (16 months old) were randomly divided into four groups: an older control group (OC group), supplementation with RES group (RES group), ET group (ET group), and a combination of ET and RES supplementation group (ET+RES group). Other 10-week-old mice were used as a young control group (Y-Ctrl group). In this study, exercise performance was evaluated using forelimb grip strength and exhaustive swimming time, as well as levels of plasma lactate, ammonia, glucose, and creatine kinase after an acute swimming exercise. Our results showed that the forelimb grip strength of mice in the ET+RES group was significantly higher than those in the OC, RES, and ET groups (by 1.3-, 1.2-, and 1.1-fold, respectively, p < 0.05), and exhibited no difference with the Y-Ctrl group. The endurance swimming test showed that swimming times of the ET and ET+RES groups were significantly longer than those of the OC and RES groups. Moreover, plasma lactate and ammonia levels of the ET + RES group after acute swimming exercise were significantly lower compared to the OC group (p < 0.05). Thus, it was suggested that by combining RES supplementation with ET for 4 weeks, the muscle strength and endurance performance of aged mice were significantly improved compared to the single intervention with either RES or ET alone. This combination might help shorten the extent of deterioration accompanying the aging process.

  17. Effects of age at first-pairing on the reproductive performance of Mongolian gerbils (Meriones unguiculatus).

    PubMed

    Kai, O; Sakemi, K; Suzuki, Y; Sonoda, Y; Imai, K

    1995-10-01

    Effects of age at first-pairing on the reproductive performance of the gerbil were studied throughout the reproductive life. Six groups of 7-30 female gerbils were paired monogamously with males at different ages. Out of 101 pairs in 6 groups, 79 (78.2%) produced 1 or more litters. The mean litter size at birth and mean weaning rate of 846 litters were 4.4 (totally 3,733 pups) and 67.4% (2,517 pups), respectively. Reproduction was compared in the 6 age groups. The littering rate (No. of females with litters/No. of female paired) was significantly lower in two groups in which mature females were paired with age-matched males (Group 4) or the oldest females with younger, sexually mature males (Group 6). The interval from pairing to the first litter was shortest in two groups in which mature females were paired with one month older, sexually mature males (Groups 3 and 5). Although the oldest pairs (Group 6) produced about 7 litters, the pairs from the other 5 groups produced about 10 or more litters throughout their reproductive life. The weaning rate was significantly higher in Group 6 (the oldest pairs) than in the younger groups. The effects of parity on reproduction were estimated from the data for the 61 pairs which produced more than 8 litters in the 6 groups. The number of pups at birth and the weaning rate were decreased in last 20-30% of the total parity in all 6 groups, although the age at the last litter in all groups was significantly different. The data suggest that any decline in reproduction may be due to not age but parity in the Mongolian gerbil.

  18. White matter integrity supports BOLD signal variability and cognitive performance in the aging human brain.

    PubMed

    Burzynska, Agnieszka Z; Wong, Chelsea N; Voss, Michelle W; Cooke, Gillian E; McAuley, Edward; Kramer, Arthur F

    2015-01-01

    Decline in cognitive performance in old age is linked to both suboptimal neural processing in grey matter (GM) and reduced integrity of white matter (WM), but the whole-brain structure-function-cognition associations remain poorly understood. Here we apply a novel measure of GM processing-moment-to-moment variability in the blood oxygenation level-dependent signal (SDBOLD)-to study the associations between GM function during resting state, performance on four main cognitive domains (i.e., fluid intelligence, perceptual speed, episodic memory, vocabulary), and WM microstructural integrity in 91 healthy older adults (aged 60-80 years). We modeled the relations between whole-GM SDBOLD with cognitive performance using multivariate partial least squares analysis. We found that greater SDBOLD was associated with better fluid abilities and memory. Most of regions showing behaviorally relevant SDBOLD (e.g., precuneus and insula) were localized to inter- or intra-network "hubs" that connect and integrate segregated functional domains in the brain. Our results suggest that optimal dynamic range of neural processing in hub regions may support cognitive operations that specifically rely on the most flexible neural processing and complex cross-talk between different brain networks. Finally, we demonstrated that older adults with greater WM integrity in all major WM tracts had also greater SDBOLD and better performance on tests of memory and fluid abilities. We conclude that SDBOLD is a promising functional neural correlate of individual differences in cognition in healthy older adults and is supported by overall WM integrity.

  19. Whole-Body Vibration Training and Its Application to Age-Related Performance Decrements: An Exploratory Analysis.

    PubMed

    Hawkey, Adam; Griffiths, Katie; Babraj, John; Cobley, James N

    2016-02-01

    Middle age is associated with a pronounced decline in power and flexibility. Whilst whole-body vibration training (WBVT) improves performance in a range of populations, whether WBVT can improve muscle power and flexibility in a middle-aged population is not known. The present study aimed to determine the influence of 5 weeks progressive WBVT in middle-aged (45-55 years) and younger (20-30 years) recreationally active females. Participants in each age group were randomly allocated to an intervention (WBVT) or control group. The WBVT groups trained for 5 weeks on a vibration platform, while the control groups performed identical exercises, with no vibration. Prior to, and after, the 5-week study vertical countermovement jump (VCMJ) and range of motion (ROM) performance were measured. WBVT significantly (p = 0.001) improved VCMJ performance when compared to the control groups. This improvement was significantly (p = 0.001) greater in the middle-aged compared with the younger WBVT group. WBVT significantly (p = 0.001) improved ROM irrespective of age. Taken together, these results suggest that WBVT can off-set age related performance decrements, which has therapeutic implications for musculoskeletal aging. Therefore, WBVT could be undertaken to minimise age-related performance deterioration in middle-aged female populations.

  20. Preservation of Cognitive Performance with Age during Exertional Heat Stress under Low and High Air Velocity

    PubMed Central

    Wright Beatty, Heather E.; Keillor, Jocelyn M.; Hardcastle, Stephen G.; Boulay, Pierre; Kenny, Glen P.

    2015-01-01

    Older adults may be at greater risk for occupational injuries given their reduced capacity to dissipate heat, leading to greater thermal strain and potentially cognitive decrements. Purpose. To examine the effects of age and increased air velocity, during exercise in humid heat, on information processing and attention. Methods. Nine young (24 ± 1 years) and 9 older (59 ± 1 years) males cycled 4 × 15 min (separated by 15 min rest) at a fixed rate of heat production (400 W) in humid heat (35°C, 60% relative humidity) under 0.5 (low) and 3.0 (high) m·s−1 air velocity wearing coveralls. At rest, immediately following exercise (end exercise), and after the final recovery, participants performed an abbreviated paced auditory serial addition task (PASAT, 2 sec pace). Results. PASAT numbers of correct responses at end exercise were similar for young (low = 49 ± 3; high = 51 ± 3) and older (low = 46 ± 5; high = 47 ± 4) males and across air velocity conditions, and when scored relative to age norms. Psychological sweating, or an increased sweat rate with the administration of the PASAT, was observed in both age groups in the high condition. Conclusion. No significant decrements in attention and speeded information processing were observed, with age or altered air velocity, following intermittent exercise in humid heat. PMID:25874223

  1. Summary Report of Cable Aging and Performance Data for Fiscal Year 2014.

    SciTech Connect

    Celina, Mathias Christopher; Celina, Mathias Christopher; Redline, Erica Marie; Redline, Erica Marie; Bernstein, Robert; Bernstein, Robert; Quintana, Adam; Quintana, Adam; Giron, Nicholas Henry; Giron, Nicholas Henry; White II, Gregory Von; White II, Gregory Von

    2014-09-01

    As part of the Light Water Reactor Sustainability Program, science - based engineering approaches were employed to address cable degradation behavior under a range of exposure environments. Experiments were conducted with the goal to provide best guidance for aged material states, remaining life and expected performance under specific conditions for a range of cable materials. Generic engineering tests , which focus on rapid accelerated aging and tensile elongation , were combined with complementar y methods from polymer degradation science. Sandia's approach, building on previous years' efforts, enabled the generation of some of the necessary data supporting the development of improved lifetime predictions models, which incorporate known material b ehaviors and feedback from field - returned 'aged' cable materials. Oxidation rate measurements have provided access to material behavior under low dose rate thermal conditions, where slow degradation is not apparent in mechanical property changes. Such da ta have shown aging kinetics consistent with established radiati on - thermal degradation models. ACKNOWLEDGEMENTS We gratefully acknowledge ongoing technical support at the LICA facility and extensive sample handling provided by Maryla Wasiolek and Don Hans on. Sam Durbin and Patrick Mattie are recognized for valuable guidance throughout the year and assistance in the preparation of the final report. Doug Brunson is appreciated for sample analysis, compilation and plotting of experimental data.

  2. Concurrent language and motor performance in bilinguals: a test of the age of acquisition hypothesis.

    PubMed

    Furtado, J C; Webster, W G

    1991-12-01

    The objective of the present study was to test the hypothesis that the age at which a second language is acquired influences the pattern of cerebral lateralization associated with that language. Subjects who differed in terms of the age at which they had acquired their second language (English or French) were tested on a concurrent task paradigm involving motor and language performance. Hemispheric processing was inferred from the pattern of lateralized and generalized interference between the tasks. No support was found for the age-of-acquisition hypothesis. Instead, the data indicated a language-specific effect. Regardless of age of acquisition and of whether the first language was English or French, bilingual subjects showed lateralized interference effects consistent with left-hemisphere processing when reading in English and translating from French into English, but no lateralized interference when reading in French and translating from English into French. Whether this effect reflects characteristics of the two languages or the influence of social factors in subject-experimenter interaction is considered.

  3. The age-related performance decline in Ironman triathlon starts earlier in swimming than in cycling and running.

    PubMed

    Käch, Ilja; Rüst, Christoph A; Nikolaidis, Pantelis T; Rosemann, Thomas; Knechtle, Beat

    2017-02-21

    In Ironman triathlon, the number of overall male and female finishers increased in the last 30 years, while an improvement in performance has been reported. Studies concluding these numbers only analysed the top ten athletes per age group instead of all finishers, therefore a selection bias might have occurred. The aim of the present study was to investigate participation, performance and the age-related performance decline of all pro and age group triathletes ranked in all Ironman triathlons held worldwide between 2002 and 2015. Split and overall race times of 329,066 (80%) male and 81,815 (20%) female athletes competing in 253 different Ironman triathlon races were analysed. The number of finishers increased in all age groups with exception of women in age group 75-79 years. In pro athletes, performance improved in all disciplines. In age group athletes, performance improved in younger age groups for running (18-24 to 40-44 years) and older age groups for swimming (50-54 to 65-69 years) and cycling (35-39 to 55-59 years), while it impaired in younger age groups for swimming (18-24 to 45-49 years) and cycling (18-24 to 30-34), and older age groups in running (45-49 to 70-74 years). The age-related performance decline started in women in age group 25-29 years in swimming and in age group 30-34 years in cycling, running and overall race time, whereas it started in men in age group 25-29 years in swimming and in age group 35-39 years in cycling, running and overall race time. For athletes and coaches, performance improved in younger age groups for running and older age groups for swimming and cycling and the age-related decline in performance started earlier in swimming than in cycling and running. In summary, women should start competing in Ironman triathlon before the age of 30 years and men before the age of 35 years to achieve their personal best Ironman race time.

  4. Dynamic Functional Reorganizations and Relationship with Working Memory Performance in Healthy Aging

    PubMed Central

    Sala-Llonch, Roser; Arenaza-Urquijo, Eider M.; Valls-Pedret, Cinta; Vidal-Piñeiro, Dídac; Bargalló, Nuria; Junqué, Carme; Bartrés-Faz, David

    2012-01-01

    In recent years, several theories have been proposed in attempts to identify the neural mechanisms underlying successful cognitive aging. Old subjects show increased neural activity during the performance of tasks, mainly in prefrontal areas, which is interpreted as a compensatory mechanism linked to functional brain efficiency. Moreover, resting-state studies have concluded that elders show disconnection or disruption of large-scale functional networks. We used functional MRI during resting-state and a verbal n-back task with different levels of memory load in a cohort of young and old healthy adults to identify patterns of networks associated with working memory and brain default mode. We found that the disruption of resting-state networks in the elderly coexists with task-related overactivations of certain brain areas and with reorganizations within these functional networks. Moreover, elders who were able to activate additional areas and to recruit a more bilateral frontal pattern within the task-related network achieved successful performance on the task. We concluded that the balanced and plastic reorganization of brain networks underlies successful cognitive aging. This observation allows the integration of several theories that have been proposed to date regarding the aging brain. PMID:22701409

  5. The relationship of scoring treatment and age in perceptual-integrative performance.

    PubMed

    Klodin, V M

    1976-07-01

    The present study was designed to reexamine the hypothesis that timed perceptual-integrative performance tests are negatively biased measures of the abilities of the elderly. Unlike an earlier study by Doppelt and Wallace (1955) which did not support this hypothesis, the current study consisted of a college-age group in addition to the elderly group, and also included an additional scoring treatment. Each subject was tested with the WAIS Block Design and Object Assembly. Tests were scored in three ways: (1) Standard scoring (WAIS Manual); (2) "regular" scoring (timed, omitting bonus points); (3) "Irregular" scoring (untimed, omitting bonus points). For both tests, Age, Scoring, and the Age by Scoring ineraction were significant. Post hoc analyses for significant effects suggest that the elderly are helped most by additional solution time, whereas younger adults derive greater benefits from the bonus points for quick performance. The results also suggest that subjects must be of sufficiently high ability to effectively use increased or unlimited solution time.

  6. Physical Performance of Brazilian Rugby Players From Different Age Categories and Competitive Levels.

    PubMed

    Kobal, Ronaldo; Nakamura, Fábio Y; Moraes, José E; Coelho, Maurício; Kitamura, Katia; Cal Abad, Cesar C; Pereira, Lucas A; Loturco, Irineu

    2016-09-01

    Kobal, R, Nakamura, FY, Moraes, JE, Coelho, M, Kitamura, K, Cal Abad, CC, Pereira, LA, and Loturco, I. Physical performance of Brazilian rugby players from different age categories and competitive levels. J Strength Cond Res 30(9): 2433-2439, 2016-The aim of this study was to compare the anthropometric characteristics and physical capacities (vertical jumping, speed, agility, and endurance abilities) among different age categories of Brazilian rugby players from the same high-level club and to compare their respective data with those obtained from the national team players. Eighty-eight men Brazilian rugby players from 4 different age categories were divided into 4 different groups (i.e., under-15 [U-15], under-17 [U-17], under-19 [U-19], and professional senior team [PRO]) and a group composed of players from the Brazilian national team (NAT). Anthropometric measures (i.e., height and body mass), squat jump (SJ) and countermovement jump (CMJ) tests , 2 agility tests (change of direction [COD] and proagility), 40-m sprinting, and the Yo-Yo endurance test (level 1) were compared among the groups using an analysis of covariance (multivariable multivariate analysis of covariance) with the body mass as a covariate. The NAT group demonstrated significantly greater performances in all variables compared with the U-15, U-17, U-19, and PRO groups (p ≤ 0.05). Moreover, the PRO group demonstrated better performances in vertical jumping assessments (i.e., SJs and CMJs) and agility tests (i.e., COD and proagility) than the younger categories (p ≤ 0.05). Finally, except for the U-15 group, no significant differences were found between the young age-categories in sprint and endurance capacities. These findings show that, throughout the maturation process, rugby players improve their muscle power and agility abilities without presenting significant increases in endurance and sprinting capacities. Importantly, this does not hold true for players from the NAT group, who

  7. Prediction of endurance running performance for middle-aged and older runners.

    PubMed

    Takeshima, N; Tanaka, K

    1995-03-01

    The purpose of this study was to develop regression equations that would sufficiently predict the endurance running performance (ERP) of middle-aged and older runners (n = 55, 43-79 years). Among many independent variables which were selected as possible predictors of the ERP, oxygen uptake corresponding to the lactate threshold (VO2@LT), or age was found to be the single best predictor. Some variables representing training habits correlated significantly but only moderately with the ERP. Linear multiple regression equations developed in this study were: V5km = 4.203 + 0.054X1 - 0.028X2 (r = 0.87) V5km = 4.436 + 0.045X1 - 0.033X2 + 0.005X3 (r = 0.89) V10km = 4.252 + 0.042X1 - 0.026X2 (r = 0.79) V10km = 4.371 + 0.037X1 - 0.031X2 + 0.005X3 (r = 0.82) VM = 3.207 + 0.048X1 - 0.022X2 (r = 0.91) VM = 3.707 + 0.038X1 - 0.031X2 + 0.005X3 (r = 0.93) where V5km, V10km and VM are the mean running velocity at 5 km, 10 km and marathon races, respectively, and X1 = VO2@LT (ml kg-1 min-1), X2 = age (year), and X3 = average running duration per workout (min). We suggest that the ERP of middle-aged and older runners can be predicted from a linear combination of VO2@LT and age or a combination of these variables plus average running duration per workout.

  8. Chronic nicotine improves working and reference memory performance and reduces hippocampal NGF in aged female rats.

    PubMed

    French, Kristen L; Granholm, Ann-Charlotte E; Moore, Alfred B; Nelson, Matthew E; Bimonte-Nelson, Heather A

    2006-05-15

    The cholinergic system is involved in cognition and several forms of dementia, including Alzheimer's disease, and nicotine administration has been shown to improve cognitive performance in both humans and rodents. While experiments with humans have shown that nicotine improves the ability to handle an increasing working memory load, little work has been done in animal models evaluating nicotine effects on performance as working memory load increases. In this report, we demonstrate that in aged rats nicotine improved the ability to handle an increasing working memory load as well as enhanced performance on the reference memory component of the water radial arm maze task. The dose required to exert these effects (0.3mg/kg/day) was much lower than doses shown to be effective in young rats and appears to be a lower maintenance dose than is seen in light to moderate smokers. In addition, our study reports a nicotine-induced reduction in nerve growth factor (NGF) protein levels in the hippocampus of the aged rat. The effects of nicotine on hippocampal NGF levels are discussed as a potential mechanism of nicotine-induced improvements in working and reference memory.

  9. Performance of the CogState computerized battery in the Mayo Clinic Study on Aging

    PubMed Central

    Mielke, Michelle M.; Machulda, Mary M.; Hagen, Clinton E.; Edwards, Kelly K.; Roberts, Rosebud O.; Pankratz, V. Shane; Knopman, David S.; Jack, Clifford R.; Petersen, Ronald C.

    2015-01-01

    Background The feasibility and validity of brief computerized cognitive batteries at the population-level are unknown. Methods Non-demented participants (n = 1660, age 50–97) in the Mayo Clinic Study on Aging completed the computerized CogState battery and standard neuropsychological battery. The correlation between tests was examined and comparisons between CogState performance on the personal computer (PC) and iPad (n = 331), and in the Clinic vs. at home (n = 194), were assessed. Results We obtained valid data on >97% of participants on each test. Correlations between the CogState and neuropsychological tests ranged from −0.462 to 0.531. While absolute differences between the PC and iPad were small and participants preferred the iPad, performance on the PC was faster. Participants performed faster on Detection, One Card Learning, and One Back at home compared to the Clinic. Conclusions The computerized CogState battery, especially the iPad, was feasible, acceptable, and valid in the population. PMID:25858683

  10. Micronutrient supplementation improves physical performance measures in Asian Indian school-age children.

    PubMed

    Vaz, Mario; Pauline, Maria; Unni, Uma S; Parikh, Panam; Thomas, Tinku; Bharathi, A V; Avadhany, Sandhya; Muthayya, Sumithra; Mehra, Ruchika; Kurpad, Anura V

    2011-11-01

    Micronutrients are important in physical work capacity and therefore performance. The impact of a multi-micronutrient-fortified nutritional beverage on physical performance measures among clinically healthy school-age children was assessed in a double-blind (for test and placebo groups), placebo-controlled, randomized trial in children aged between 7 and 10.5 y (n = 300). The participants with height- and weight-for-age Z-scores between 0 and ≥ -3 were randomized to 1 of 3 study arms: fortified choco-malt beverage powder (F), matched energy equivalent unfortified placebo (U), and untreated control (C). Participants in the F and C groups were given 40 g fortified (19 key vitamins and minerals) and unfortified choco-malt beverage, respectively, daily for 120 d. Primary efficacy outcomes included endurance and aerobic capacity using a 20-m shuttle test and step test. Other physical performance measures included speed (40-m sprint), visual reaction time, maximal hand grip, and forearm static endurance. Micronutrient status included thiamin, riboflavin, folate, niacin, iron, pyridoxal phosphate, and vitamins B-12 and C. All measurements were made at baseline and the end of the intervention. There was a within-subject increase in aerobic capacity and whole body endurance (P < 0.05) accompanied by a significant improvement in the status of iron thiamin, riboflavin, pyridoxal phosphate, folate, and vitamins C and B-12 in the F group compared to the within-subject changes in the other 2 groups (P < 0.05). The study suggests that multiple micronutrient supplementation in similar populations may be beneficial in improving micronutrient status and enhancing aerobic capacity and endurance in children.

  11. Childhood conditions and current physical performance among non-institutionalized individuals aged 50+ in Israel

    PubMed Central

    2017-01-01

    Adverse socioeconomic conditions in childhood have been previously linked with high risk of various health conditions. However, the association with future physical function has been less studied. Hand grip strength and chair-rising time are objective measures of physical capability indicating current and future health outcomes. The aim of this study was to test the hypothesis that perceived socio-economic status in childhood is related to current measures of physical function, among Israeli participants of the Survey of Health, Ageing and Retirement in Europe project. The study included 2300 participants aged 50 years or older (mean age 68 ± 10; 56 % women). Generalized linear regression models were used to examine the associations of childhood wealth and number of books in residence with grip strength and time to complete five rises from a chair. Logistic regression models were used to assess the relationships between the early life conditions and the ability to perform the physical tests. Adjustment was made for current income or household wealth, and for demographic, anthropometric, health, and life-style measures. Being wealthy and having a large number of books at home in childhood was associated with a stronger hand grip and a better chair-rise test performance. These associations were more robust in women compared to men, and persisted after adjustment for potential covariates. In addition, childhood wealth and number of books were associated with lower risk of being unable to perform the tests. Thus, early-life programming may contribute to physical function indicators in mid- and late-life. PMID:28190995

  12. Microstructural characterization of the chemomechanical behavior of asphalt in terms of aging and fatigue performance properties

    NASA Astrophysics Data System (ADS)

    Allen, Robert Grover

    The study of asphalt chemo-mechanics requires a basic understanding of the physical properties and chemical composition of asphalt and how these properties are linked to changes in performance induced by chemical modifications. This work uniquely implements the framework of chemo-mechanics by investigating two types of chemical modification processes, natural (oxidative aging) and synthetic (chemical doping) as they relate not only to macro-scale properties of asphalt binder but also to the asphalt microstructure and nanorheology. Furthermore, this study demonstrates the application of atomic force microscopy (AFM) imaging and the extraction of nano-scale engineering properties, i.e. elastic modulus, relaxation modulus, and surface energy, as a method to predict performance related to the fatigue characteristics of asphalt binders by modeling intrinsic material flaws present amongst phase interfaces. It was revealed that oxidative aging induces substantial microstructural changes in asphalt, including variations in phase structure, phase properties, and phase distribution. It has also been shown that certain asphalt chemical parameters have a consistent and measureable effect on the asphalt microstructure that is observed with AFM. In fact, particular phases that emerged via chemical doping revealed a surprising correlation between oxidative aging and the saturates chemical parameter of asphalt in terms of how they explicitly impact durability and performance of asphalt. By implementing a crack initiation model---which requires measureable microstructural characteristics as an input parameter---it was found that microstructural flaws (depending on the extremity) can have a more profound impact on asphalt performance than the properties of the material located between the flaws. It was also discovered by comparing the findings to performance data in the Strategic Highway Research Program's (SHRP's) Materials Reference Library (MRL), that the crack initiation model

  13. Age differences in cognitive performance: A study of cultural differences in Historical Context.

    PubMed

    Ojeda, Natalia; Aretouli, Eleni; Peña, Javier; Schretlen, David J

    2016-03-01

    Ethnicity and cultural experience can affect neuropsychological performance, but they are rarely assessed in historical context. Attention measures are considered strongly biologically determined and therefore potentially culture-fair. In this study, we assessed the cross-cultural equivalence of Spanish and English versions of the Trail Making Test (TMT; Reitan, 1958, Perceptual and Motor Skills, 8, 271-276) and the Brief Test of Attention (BTA; Schretlen et al., 1996, The Clinical Neuropsychologist, 10, 80-89) in two large samples of Americans (N = 203) and Spaniards (N = 213), divided into younger and older subgroups. The older Spaniards lived under Franco's political regime (1936-1975), whereas the Americans never experienced such repression. Overall, TMT performance was culture-sensitive, whereas BTA performance was not. However, when both groups were stratified by age, cultural differences in TMT performance were restricted to older participants, suggesting that historical experience across generations might have contributed to the observed differences in cognitive performance. Even such basic cognitive processes as attention, working memory, and resource sharing might be shaped to some degree by historical experiences that contribute to cultural differences.

  14. Tracking 10-year competitive winning performance of judo athletes across age groups.

    PubMed

    Julio, Ursula F; Takito, Monica Y; Mazzei, Leandro; Miarka, Bianca; Sterkowicz, Stanislaw; Franchini, Emerson

    2011-08-01

    Little information is available concerning early specialization and competitive success in judo across the early training years. Thus, the present objective was to verify the stability of individual competitive performance of a state-level championship for judo athletes who had been previously successful. For this, 406 athletes from six age groups (9 to 20+ years old) of each sex were followed for 10 years. Using recorded data from the São Paulo State Judo Federation beginning in 1999, the scores and standings for these judo players were analyzed. The proportion of medal winners during this period was not constant, differing from the grand mean in all groups of both 204 males and 202 females. At the end of this period, only 7% of the male and 5% of the female athletes had maintained their competitive levels. Successful competitive performance in early judo competition was not associated with success later in adulthood.

  15. Intellectual performance after presymptomatic cranial radiotherapy for leukaemia: effects of age and sex.

    PubMed Central

    Christie, D; Leiper, A D; Chessells, J M; Vargha-Khadem, F

    1995-01-01

    Cognitive outcome, as measured by verbal and performance IQs, was compared in 35 girls and 47 boys who were in first remission for acute lymphoblastic leukaemia. All children had received presymptomatic cranial radiotherapy and intrathecal methotrexate. The mean age at diagnosis was 4.2 years and the mean elapsed time from initial diagnosis to intellectual assessment was 7.1 years. Results showed that children irradiated before the age of 4 years were impaired in certain aspects of non-verbal ability, as well as in measures of short term memory and attention, calculated by factor scores derived from selected subtests of the IQ test. Subtests requiring verbal and non-verbal reasoning showed the greatest impairment after early diagnosis and treatment. In addition girls were selectively impaired in verbal IQ and other aspects of verbal ability, with the degree of impairment exacerbated by early treatment. No relationship was found between degree of impairment and either time since treatment or number of methotrexate injections. It is concluded that early age at irradiation increases the risk of impaired intellectual outcome, particularly in girls. PMID:7574857

  16. Paternal but not maternal age influences early-life performance of offspring in a long-lived seabird

    PubMed Central

    Fay, Rémi; Barbraud, Christophe; Delord, Karine; Weimerskirch, Henri

    2016-01-01

    Variability in demographic traits between individuals within populations has profound implications for both evolutionary processes and population dynamics. Parental effects as a source of non-genetic inheritance are important processes to consider to understand the causes of individual variation. In iteroparous species, parental age is known to influence strongly reproductive success and offspring quality, but consequences on an offspring fitness component after independence are much less studied. Based on 37 years longitudinal monitoring of a long-lived seabird, the wandering albatross, we investigate delayed effects of parental age on offspring fitness components. We provide evidence that parental age influences offspring performance beyond the age of independence. By distinguishing maternal and paternal age effects, we demonstrate that paternal age, but not maternal age, impacts negatively post-fledging offspring performance. PMID:27053738

  17. The effects of texting on driving performance in a driving simulator: the influence of driver age.

    PubMed

    Rumschlag, Gordon; Palumbo, Theresa; Martin, Amber; Head, Doreen; George, Rajiv; Commissaris, Randall L

    2015-01-01

    Distracted driving is a significant contributor to motor vehicle accidents and fatalities, and texting is a particularly significant form of driver distraction that continues to be on the rise. The present study examined the influence of driver age (18-59 years old) and other factors on the disruptive effects of texting on simulated driving behavior. While 'driving' the simulator, subjects were engaged in a series of brief text conversations with a member of the research team. The primary dependent variable was the occurrence of Lane Excursions (defined as any time the center of the vehicle moved outside the directed driving lane, e.g., into the lane for oncoming traffic or onto the shoulder of the road), measured as (1) the percent of subjects that exhibited Lane Excursions, (2) the number of Lane Excursions occurring and (3) the percent of the texting time in Lane Excursions. Multiple Regression analyses were used to assess the influence of several factors on driving performance while texting, including text task duration, texting skill level (subject-reported), texting history (#texts/week), driver gender and driver age. Lane Excursions were not observed in the absence of texting, but 66% of subjects overall exhibited Lane Excursions while texting. Multiple Regression analysis for all subjects (N=50) revealed that text task duration was significantly correlated with the number of Lane Excursions, and texting skill level and driver age were significantly correlated with the percent of subjects exhibiting Lane Excursions. Driver gender was not significantly correlated with Lane Excursions during texting. Multiple Regression analysis of only highly skilled texters (N=27) revealed that driver age was significantly correlated with the number of Lane Excursions, the percent of subjects exhibiting Lane Excursions and the percent of texting time in Lane Excursions. In contrast, Multiple Regression analysis of those drivers who self-identified as not highly skilled

  18. White Matter Integrity Supports BOLD Signal Variability and Cognitive Performance in the Aging Human Brain

    PubMed Central

    Burzynska, Agnieszka Z.; Wong, Chelsea N.; Voss, Michelle W.; Cooke, Gillian E.; McAuley, Edward; Kramer, Arthur F.

    2015-01-01

    Decline in cognitive performance in old age is linked to both suboptimal neural processing in grey matter (GM) and reduced integrity of white matter (WM), but the whole-brain structure-function-cognition associations remain poorly understood. Here we apply a novel measure of GM processing–moment-to-moment variability in the blood oxygenation level-dependent signal (SDBOLD)—to study the associations between GM function during resting state, performance on four main cognitive domains (i.e., fluid intelligence, perceptual speed, episodic memory, vocabulary), and WM microstructural integrity in 91 healthy older adults (aged 60-80 years). We modeled the relations between whole-GM SDBOLD with cognitive performance using multivariate partial least squares analysis. We found that greater SDBOLD was associated with better fluid abilities and memory. Most of regions showing behaviorally relevant SDBOLD (e.g., precuneus and insula) were localized to inter- or intra-network “hubs” that connect and integrate segregated functional domains in the brain. Our results suggest that optimal dynamic range of neural processing in hub regions may support cognitive operations that specifically rely on the most flexible neural processing and complex cross-talk between different brain networks. Finally, we demonstrated that older adults with greater WM integrity in all major WM tracts had also greater SDBOLD and better performance on tests of memory and fluid abilities. We conclude that SDBOLD is a promising functional neural correlate of individual differences in cognition in healthy older adults and is supported by overall WM integrity. PMID:25853882

  19. Gross and fine motor performance in healthy Swedish children aged fifteen and eighteen months.

    PubMed

    Lundberg, A

    1979-02-01

    Gross and fine motor performance have been assessed in thirtynine 15-month-old and thirtynine 18-month-old children selected through systematic sampling from a population of healthy newborns. The performance was estimated with corresponding subscales of Denver Developmental Screening Test and Motor age test. In addition fine motor performance was assessed by the "Drawing test" for which the expected performance at 15 and 18 months is given. Of the 78 children, 83% had crawled on hand and knees, 9% crept on their tummy and 8% shuffled on their bottom before walking. Median age for walking was 11.8 months, the 97th percentile 16.0 months. Of the 15-month-old children, 90% walked with ability to stop and start, and 90% of the 18-month-old were in addition able to walk backwards, run stiffly, climb up and down a standard staircase and seat themselves in an armchair of suitable size. Of the 15-month-old, 90% were able to build a tower of two cubes or more, and 90% of the 18-month-old were able to build a tower of three cubes or more (size 1 1/2 inch). Almost 90% of the 15-month-old and all of the 18-month-old had the cognitive ability to coordinate a crayon and paper. In drawing attempts of the 15 month-old, the weak unstable combination with a top-tong/tong grasp and 1/2 pronated forearm was the dominating hand-grasp fore-arm position. In the 18 month-old a more mature grasp and forearm combination, mainly palmar grasp with or without stablizing index finger + overpronated forearm, was found.

  20. Trill performance components vary with age, season, and motivation in the banded wren

    PubMed Central

    Vehrencamp, S. L.; Yantachka, J.; Hall, M. L.; de Kort, S. R.

    2012-01-01

    Acoustic displays with difficult-to-execute sounds are often subject to strong sexual selection, because performance levels are related to the sender’s condition or genetic quality. Performance may also vary with age, breeding stage, and motivation related to social context. We focused on within-male variation in four components of trill performance in banded wren (Thryophilus pleurostictus) songs: note consistency, frequency bandwidth, note rate and vocal deviation. The latter is a composite measure reflecting deviation from the performance limit on simultaneously maximizing both frequency bandwidth and note rate. We compared the changes in these song parameters at three time scales: over the course of years, across the breeding season, and at different times of the day with contrasting agonistic contexts. Vocal deviation decreased and note consistency increased over years, suggesting that experience may improve individual proficiency at singing trills. Consistency also increased across the season, confirming that practice is important for this parameter. Although there was no significant seasonal change in vocal deviation, one of its components, note rate, increased during the season. Neither vocal deviation nor consistency varied with agonistic context. However, note rate increased during playback experiments simulating territorial intrusions compared to dawn chorus singing. The magnitude of a male’s increase in note rate was positively correlated with his aggressive behavior during the playback experiment. Thus consistency, bandwidth, and vocal deviation indicate age, whereas trill rate flexibly indicates the singer’s aggressive motivation. We also found evidence of a within-male trade-off between vocal deviation and consistency. PMID:23543812

  1. Age-related differences in stepping performance during step cycle-related removal of vision.

    PubMed

    Chapman, G J; Hollands, M A

    2006-10-01

    The aim of the present study was to investigate whether there are age-related changes in the ability of individuals to use vision to plan (feedforward control) and guide (on-line control) foot placement during locomotion. This aim was achieved by constraining the availability of vision and comparing the effects on the stepping performances of older and young adults during a precision stepping task. We experimentally controlled the availability of visual information such that: (1) vision was only available during each stance phase of the targeting limb, (2) vision was only available during each swing phase of the targeting limb or (3) vision was always available. Our visual manipulations had relatively little effect on younger adults' stepping performance as demonstrated by their missing the target on less than 10% of occasions. However, there were clear visual condition-related differences in older adults' stepping performance. When vision was only available during the stance phase of the targeting limb, older adults demonstrated significantly larger foot placement error and associated task failure rate (23%) than trials in which vision was always available (10%). There was an even greater increase in older adults' foot placement error and task failure rate (42%) during trials in which vision was only available in the swing phase than the other visual conditions. These findings suggest that older adults need vision at particular times during the step cycle, to effectively pre-plan future stepping movements. We discuss the evidence that these age-related changes in performance reflect decline in visual and visuomotor CNS pathways.

  2. Cognitive Performance in Women Aged 50 Years and Older With and Without Fibromyalgia

    PubMed Central

    2014-01-01

    Objectives. Persons with fibromyalgia (FM) report having cognitive dysfunction. Neuropsychological performance was compared across a variety of domains in 43 women with FM (M age = 63 years) and in 44 women without FM (M age = 65 years). Method. Measures included explicit memory (Consortium to Establish a Registry for Alzheimer’s Disease [CERAD] immediate/delayed recall, delayed recognition), aspects of executive function including interference/inhibition (Stroop Color/Word test), working memory (Digit Span Forward/Backward), set-shifting/complex sequencing (Trails B), monitoring (verbal fluency: naming animals), processing speed (Trails A, Digit Symbol Substitution Coding), and problem solving (Everyday Problems Test). Results. Women with FM performed more poorly than controls on executive function (Stroop Color/Word) and one processing speed measure (Digit Symbol Substitution Coding). Discussion. Results partly support altered cognitive function in FM. Mixed findings across cognitive domains among individuals with or without FM is consistent with the literature and suggest that factors beyond those typically controlled for (e.g., heterogeneity in FM) may be influencing findings. Future research is warranted. PMID:23275498

  3. Performance of repair welds on aged Cr-Mo piping girth welds

    SciTech Connect

    Viswanathan, R.; Gandy, D.W.

    1999-10-01

    This article documents the results of an industry survey of weld repair practices and describes the results of experimental evaluations performed on service-aged 2{1/4}Cr-1 Mo steel piping using SMAW with both conventional postweld heat treatments and temper bead repair techniques. The overall results of this program provide substantial evidence that service-aged piping systems can be successfully weld repaired with and without postweld heat treatments and that life extension by several decades is achievable under the right design and repair conditions. Weld repairs performed on degraded exservice welds resulted in restoration or improvement of tensile and creep properties. Microhardness test results within the heat-affected zone of each weldment indicated that the temper bead weld repairs produced only slightly higher peak hardness values than those measured for the fully postweld heat treated repairs. Finally, in terms of toughness, temper bead weld repairs consistently produced higher impact properties than those measured for the postweld heat treated weldments. Gas tungsten arc weld repairs with postweld heat treatment resulted in the best combination of tensile strength, uniform microhardness distribution across the weld, Charpy toughness, and creep rupture life.

  4. Performance of repair welds on aged Cr-Mo piping girth welds

    NASA Astrophysics Data System (ADS)

    Viswanathan, R.; Gandy, D. W.

    1999-10-01

    This article documents the results of an industry survey of weld repair practices and describes the results of experimental evaluations performed on service-aged 21/4 Cr-1Mo steel piping using SMAW with both conventional postweld heat treatments and temper bead repair techniques. The overall results of this program provide substantial evidence that service-aged piping systems can be successfully weld repaired with and without postweld heat treatments and that life extension by several decades is achievable under the right design and repair conditions. Weld repairs performed on degraded exservice welds resulted in restoration or improvement of tensile and creep properties. Microhardness test results within the heat-affected zone of each weldment indicated that the temper bead weld repairs produced only slightly higher peak hardness values than those measured for the fully postweld heat treated repairs. Finally, in terms of toughness, temper bead weld repairs consistently produced higher impact properties than those measured for the postweld heat treated weldments. Gas tungsten arc weld repairs with postweld heat treatment resulted in the best combination of tensile strength, uniform microhardness distribution across the weld, Charpy toughness, and creep rupture life.

  5. Effects of protein and carbohydrate meals on mood and performance: interactions with sex and age.

    PubMed

    Spring, B; Maller, O; Wurtman, J; Digman, L; Cozolino, L

    Normal adult subjects (n = 184) consumed a high-protein or high-carbohydrate meal. Two hours later their mood and performance were tested. The effects of meal composition on mood were different for men and women, and for older and younger subjects. Females, but not males, reported greater sleepiness after a carbohydrate as opposed to a protein meal. Male subjects, but not females, reported greater calmness after a carbohydrate as opposed to a protein meal. Older subjects responded differently to meals depending upon the time of day when these were consumed. When meals were eaten for breakfast (but not for lunch) individuals 40 yr of age or older felt more tense and less calm after a protein than after a carbohydrate meal. Although older subjects reported subjective discomfort after a morning protein meal, they displayed objective performance impairments after a carbohydrate lunch. Subjects 40 yr of age or older were impaired on a test of sustained selective attention (dichotic shadowing) after consuming a high-carbohydrate lunch. The shadowing impairment after carbohydrate consumption was as pronounced without distraction as with distraction and resulted mostly from increased omission errors. Our findings suggest negative effects on concentration when older subjects consume a high-carbohydrate, low-protein lunch. These negative effects of carbohydrate consumption appear to arise predominantly from lapses of attention rather than from intrusion of distractors.

  6. The assessment of subjective visual vertical: comparison of two psychophysical paradigms and age-related performance.

    PubMed

    Baccini, Marco; Paci, Matteo; Del Colletto, Mattia; Ravenni, Michele; Baldassi, Stefano

    2014-01-01

    Perception of the subjective visual vertical (SVV) is usually assessed by asking to subjects, in complete darkness, to adjust the position of a luminous rod that is variably tilted (i.e., by the method of adjustment [ADJ]). Conversely, the two-alternative forced choice (2AFC) method requires subjects to categorize, as tilted either clockwise (CW) or counterclockwise (CCW), stimuli that are presented on a computer screen and are variably tilted from vertical. In this study, we aimed to compare the results of these two methods and investigate age-related effects on the SVV. SVV was assessed in 102 healthy individuals, 50 women and 52 men, with a mean age of 45.7 (range 20-91), using both ADJ (ten trials, initial 1°, 2°, 4°, 8°, or 12° bar tilts both CW and CCW) and 2AFC (120 stimuli with a 1°-32° variable tilt). Also, 50 of the subjects performed the ADJ test twice, with different bar lengths. We estimated bias and threshold for the two methods, and found that neither measure differed across the methods. Age was a significant predictor of threshold (2AFC, R (2) = .141; ADJ, R (2) = .190; p < .001), implying lower sensitivity with increasing age. Moreover, the ADJ method showed a significant increase of bias when the initial tilt was farthest from vertical, whereas the rod length was irrelevant. SVV measures obtained with the ADJ and 2AFC methods were comparable, but the latter measures were more resistant to artifacts that might affect the measurement. The lower sensitivity found in older persons may have an influence on their ability to interact with the environment and may contribute to impairment of postural control.

  7. Voluntary Exercise Impairs Initial Delayed Spatial Alternation Performance in Estradiol Treated Ovariectomized Middle-Aged Rats

    PubMed Central

    Neese, Steven L.; Korol, Donna L.; Schantz, Susan L.

    2013-01-01

    Estrogens differentially modulate behavior in the adult female rodent. Voluntary exercise can also impact behavior, often reversing age associated decrements in memory processes. Our research group has published a series of papers reporting a deficit in the acquisition of an operant working memory task, delayed spatial alternation (DSA), following 17β-estradiol treatment to middle-aged ovariectomized (OVX) rats. The current study examined if voluntary exercise could attenuate the 17β-estradiol induced deficits on DSA performance. OVX 12-month old Long- Evans rats were implanted with a Silastic capsule containing 17β-estradiol (10% in cholesterol: low physiological range) or with a blank capsule. A subset of the 17β-estradiol and OVX untreated rats were given free access to a running wheel in their home cage. All rats were tested for 40 sessions on the DSA task. Surprisingly, we found running wheel access to impair initial acquisition of the DSA task in 17β-estradiol treated rats, an effect not seen in OVX untreated rats given running wheel access. This deficit was driven by an increase in perseverative responding on a lever no longer associated with reinforcement. We also report for the first time a 17β-estradiol induced impairment on the DSA task following a long intertrial delay (18-sec), an effect revealed following more extended testing than in our previous studies (15 additional sessions). Overall, running wheel access increased initial error rate on the DSA task in 17β-estradiol treated middle-aged OVX rats, and failed to prevent the 17β-estradiol induced deficits in performance of the operant DSA task in later testing sessions. PMID:24013039

  8. Sex-specific age associations of ankle proprioception test performance in older adults: results from the Baltimore Longitudinal Study of Aging

    PubMed Central

    Ko, Seung-Uk; Simonsick, Eleanor; Deshpande, Nandini; Ferrucci, Luigi

    2015-01-01

    Objectives: this study was aimed to test the hypothesis that ankle proprioception assessed by custom-designed proprioception testing equipment changes with ageing in men and women. Methods: ankle proprioception was assessed in 289 participants (131 women) of the Baltimore Longitudinal Study of Aging (BLSA); the participants aged 51–95 years and were blinded during testing. Results: the average minimum perceived ankle rotation was 1.11° (SE = 0.07) in women and 1.00° (SE = 0.06) in men, and it increased with ageing in both sexes (P < 0.001, for both). Ankle tracking performance, which is the ability to closely follow with the left ankle, a rotational movement induced on the right ankle by a torque motor, declines with ageing in both men and women (P = 0.018 and P = 0.011, respectively). Conclusions: a simple, standardised method for assessing ankle proprioception was introduced in this study using a customized test instrument, software and test protocol. Age-associated reduction in ankle proprioception was confirmed from two subtests of threshold and tracking separately for women and men. Findings in this study prompt future studies to determine whether these age-associated differences in the threshold for passive motion detection and movement tracking are evident in longitudinal study and how these specific deficits in ankle proprioception are related to age-associated chronic conditions such as knee or hip osteoarthritis and type II diabetes and affect daily activities such as gait. PMID:25637144

  9. Does lifelong training temper age-related decline in sport performance? Interpreting differences between cross-sectional and longitudinal data.

    PubMed

    Young, Bradley W; Weir, Patricia L; Starkes, Janet L; Medic, Nikola

    2008-01-01

    In the face of remarkable aging trends in North American society, organized sport/physical activity is an important vehicle for promoting physical health, and a domain in which long-term participation might mitigate pessimistic trends for age decline. This investigation examined patterns of age-related decline in performance for 45 Masters runners who rigorously trained continuously for at least a decade. Longitudinal data for age and performance were collected for 200 m, 1500 m, and 10 km events retrospectively across participants' careers. Cross-sectional (CS) data representing normal patterns of aging were derived from online archives. Longitudinal data reflected within-participant training effects whereas CS data did not. Second-order regression analyses were performed separately for each data type and quadratic beta coefficients, indicative of accelerated age decline, were compared for CS and longitudinal samples on a within-event basis. Results showed evidence of accelerated decline with advancing age for both samples, although rates for longitudinal samples were moderated for the 200 m and 1500 m events. Findings for the long-distance event were anomalous. Results provide evidence for moderated age-decline in physical performance measures for individuals who sustain engagement in organized sport for lengthy periods. Discussion focuses on methodological considerations for advancing future research that contrasts CS and longitudinal samples, and the importance of encouraging sport involvement opportunities to aging individuals.

  10. The Effects of Aging, Malingering, and Traumatic Brain Injury on Computerized Trail-Making Test Performance.

    PubMed

    Woods, David L; Wyma, John M; Herron, Timothy J; Yund, E William

    2015-01-01

    The trail making test (TMT) is widely used to assess speed of processing and executive function. However, normative data sets gathered at different sites show significant inconsistencies. Here, we describe a computerized version of the TMT (C-TMT) that increases the precision and replicability of the TMT by permitting a segment-by-segment analysis of performance and separate analyses of dwell-time, move-time, and error time. Experiment 1 examined 165 subjects of various ages and found that completion times on both the C-TMT-A (where subjects connect successively numbered circles) and the C-TMT-B (where subjects connect circles containing alternating letters and numbers) were strongly influenced by age. Experiment 2 examined 50 subjects who underwent three test sessions. The results of the first test session were well fit by the normative data gathered in Experiment 1. Sessions 2 and 3 demonstrated significant learning effects, particularly on the C-TMT-B, and showed good test-retest reliability. Experiment 3 examined performance in subjects instructed to feign symptoms of traumatic brain injury: 44% of subjects produced abnormal completion times on the C-TMT-A, and 18% on the C-TMT-B. Malingering subjects could be distinguished from abnormally slow controls based on (1) disproportionate increases in dwell-time on the C-TMT-A, and (2) greater deficits on the C-TMT-A than on the C-TMT-B. Experiment 4 examined the performance of 28 patients with traumatic brain injury: C-TMT-B completion times were slowed, and TBI patients showed reduced movement velocities on both tests. The C-TMT improves the reliability and sensitivity of the trail making test of processing speed and executive function.

  11. The Effects of Aging, Malingering, and Traumatic Brain Injury on Computerized Trail-Making Test Performance

    PubMed Central

    Woods, David L.; Wyma, John M.; Herron, Timothy J.; Yund, E. William

    2015-01-01

    The trail making test (TMT) is widely used to assess speed of processing and executive function. However, normative data sets gathered at different sites show significant inconsistencies. Here, we describe a computerized version of the TMT (C-TMT) that increases the precision and replicability of the TMT by permitting a segment-by-segment analysis of performance and separate analyses of dwell-time, move-time, and error time. Experiment 1 examined 165 subjects of various ages and found that completion times on both the C-TMT-A (where subjects connect successively numbered circles) and the C-TMT-B (where subjects connect circles containing alternating letters and numbers) were strongly influenced by age. Experiment 2 examined 50 subjects who underwent three test sessions. The results of the first test session were well fit by the normative data gathered in Experiment 1. Sessions 2 and 3 demonstrated significant learning effects, particularly on the C-TMT-B, and showed good test-retest reliability. Experiment 3 examined performance in subjects instructed to feign symptoms of traumatic brain injury: 44% of subjects produced abnormal completion times on the C-TMT-A, and 18% on the C-TMT-B. Malingering subjects could be distinguished from abnormally slow controls based on (1) disproportionate increases in dwell-time on the C-TMT-A, and (2) greater deficits on the C-TMT-A than on the C-TMT-B. Experiment 4 examined the performance of 28 patients with traumatic brain injury: C-TMT-B completion times were slowed, and TBI patients showed reduced movement velocities on both tests. The C-TMT improves the reliability and sensitivity of the trail making test of processing speed and executive function. PMID:26060999

  12. Temporal stability and moderating effects of age and sex on CNTRaCS task performance.

    PubMed

    Strauss, Milton E; McLouth, Christopher J; Barch, Deanna M; Carter, Cameron S; Gold, James M; Luck, Steven J; MacDonald, Angus W; Ragland, J Daniel; Ranganath, Charan; Keane, Brian P; Silverstein, Steven M

    2014-07-01

    Research in schizophrenia has increasingly focused on incorporating measures from cognitive neuroscience, but little is known about their psychometric characteristics. Here, we extend prior research by reporting on temporal stability, as well as age and sex effects, for cognitive neuroscience paradigms optimized as part of the Cognitive Neuroscience Test Reliability and Clinical applications for Schizophrenia consortium. Ninety-nine outpatients with schizophrenia and 131 healthy controls performed 5 tasks assessing 4 constructs at 3 sessions. The constructs were (1) Goal maintenance (Dot Probe Expectancy [DPX] and AX continuous performance tasks [AX-CPT]); (2) Episodic memory (Relational and Item-Specific Encoding and Retrieval task [RiSE]); (3) Visual integration (Jittered Orientation Visual Integration task [JOVI]); and (4) Perceptual gain control (Contrast-Contrast Effect Task [CCE]). Patients performed worse than controls on all but the CCE, and the magnitude of these group differences was stable across sessions, with no sex differences observed. Improvements over sessions were seen for the AX-CPT, the DPX, and the JOVI though practice effects for the AX-CPT and the DPX were primarily present in older participants. For the AX-CPT and the JOVI, practice effects were larger for T1 to T2 than for T2 to T3. Age was associated with poor associative recognition on the RiSE and accuracy on the JOVI. Test-rest reliability ranged from poor for the JOVI threshold score to adequate to good for the DPX, AX-CPT, and JOVI accuracy measures, with RiSE and CCE measures in the moderate range. These results suggest that group differences in DPX, AX-CPT, RiSE, and JOVI are robust and consistent across repeated testing.

  13. Cognitive Decline and Reorganization of Functional Connectivity in Healthy Aging: The Pivotal Role of the Salience Network in the Prediction of Age and Cognitive Performances

    PubMed Central

    La Corte, Valentina; Sperduti, Marco; Malherbe, Caroline; Vialatte, François; Lion, Stéphanie; Gallarda, Thierry; Oppenheim, Catherine; Piolino, Pascale

    2016-01-01

    Normal aging is related to a decline in specific cognitive processes, in particular in executive functions and memory. In recent years a growing number of studies have focused on changes in brain functional connectivity related to cognitive aging. A common finding is the decreased connectivity within multiple resting state networks, including the default mode network (DMN) and the salience network. In this study, we measured resting state activity using fMRI and explored whether cognitive decline is related to altered functional connectivity. To this end we used a machine learning approach to classify young and old participants from functional connectivity data. The originality of the approach consists in the prediction of the performance and age of the subjects based on functional connectivity by using a machine learning approach. Our findings showed that the connectivity profile between specific networks predicts both the age of the subjects and their cognitive abilities. In particular, we report that the connectivity profiles between the salience and visual networks, and the salience and the anterior part of the DMN, were the features that best predicted the age. Moreover, independently of the age of the subject, connectivity between the salience network and various specific networks (i.e., visual, frontal) predicted episodic memory skills either based on a standard assessment or on an autobiographical memory task, and short-term memory binding. Finally, the connectivity between the salience and the frontal networks predicted inhibition and updating performance, but this link was no longer significant after removing the effect of age. Our findings confirm the crucial role of episodic memory and executive functions in cognitive aging and suggest a pivotal role of the salience network in neural reorganization in aging. PMID:27616991

  14. Cognitive Decline and Reorganization of Functional Connectivity in Healthy Aging: The Pivotal Role of the Salience Network in the Prediction of Age and Cognitive Performances.

    PubMed

    La Corte, Valentina; Sperduti, Marco; Malherbe, Caroline; Vialatte, François; Lion, Stéphanie; Gallarda, Thierry; Oppenheim, Catherine; Piolino, Pascale

    2016-01-01

    Normal aging is related to a decline in specific cognitive processes, in particular in executive functions and memory. In recent years a growing number of studies have focused on changes in brain functional connectivity related to cognitive aging. A common finding is the decreased connectivity within multiple resting state networks, including the default mode network (DMN) and the salience network. In this study, we measured resting state activity using fMRI and explored whether cognitive decline is related to altered functional connectivity. To this end we used a machine learning approach to classify young and old participants from functional connectivity data. The originality of the approach consists in the prediction of the performance and age of the subjects based on functional connectivity by using a machine learning approach. Our findings showed that the connectivity profile between specific networks predicts both the age of the subjects and their cognitive abilities. In particular, we report that the connectivity profiles between the salience and visual networks, and the salience and the anterior part of the DMN, were the features that best predicted the age. Moreover, independently of the age of the subject, connectivity between the salience network and various specific networks (i.e., visual, frontal) predicted episodic memory skills either based on a standard assessment or on an autobiographical memory task, and short-term memory binding. Finally, the connectivity between the salience and the frontal networks predicted inhibition and updating performance, but this link was no longer significant after removing the effect of age. Our findings confirm the crucial role of episodic memory and executive functions in cognitive aging and suggest a pivotal role of the salience network in neural reorganization in aging.

  15. An experimental test for age-related improvements in reproductive performance in a frog that cares for its young

    NASA Astrophysics Data System (ADS)

    Dugas, Matthew B.; Moore, Michael P.; Wamelink, Caitlin N.; Richards-Zawacki, Corinne L.; Martin, Ryan A.

    2015-10-01

    Reproductive performance often increases with age in long-lived iteroparous organisms, a pattern that can result from within-individual increases in effort and/or competence. In free-living populations, it is typically difficult to distinguish these mechanisms or to isolate particular features of reproduction-influencing outcomes. In captive Oophaga pumilio, a frog in which mothers provide extended offspring provisioning via trophic eggs, we experimentally manipulated the age at which females started breeding and then monitored them across repeated reproductive events. This experiment allowed us to decouple age and experience and isolate maternal care as the proximate source of any differences in performance. Younger first-time mothers produced larger broods than older first-time mothers, but did not rear more offspring to independence. Across repeated reproductive events, maternal age was unassociated with any metric of performance. At later reproductive events, however, mothers produced fewer metamorphs, and a lower proportion of individuals in their broods reached independence. These patterns suggest that performance does not improve with age or breeding experience in this frog, and that eventual declines in performance are driven by reproductive activity, not age per se. Broadly, age-specific patterns of reproductive performance may depend on the proximate mechanism by which parents influence offspring fitness and how sensitive these are to effort and competence.

  16. Narrative Performance of Gifted African American School-Aged Children From Low-Income Backgrounds

    PubMed Central

    2015-01-01

    Purpose This study investigated classroom differences in the narrative performance of school-age African American English (AAE)-speaking children in gifted and general education classrooms. Method Forty-three children, Grades 2–5, each generated fictional narratives in response to the book Frog, Where Are You? (Mayer, 1969). Differences in performance on traditional narrative measures (total number of communication units [C-units], number of different words, and mean length of utterance in words) and on AAE production (dialect density measure) between children in gifted and general education classrooms were examined. Results There were no classroom-based differences in total number of C-units, number of different words, and mean length of utterance in words. Children in gifted education classrooms produced narratives with lower dialect density than did children in general educated classrooms. Direct logistic regression assessed whether narrative dialect density measure scores offered additional information about giftedness beyond scores on the Peabody Picture Vocabulary Test–Fourth Edition (Dunn & Dunn, 2007), a standard measure of language ability. Results indicated that a model with only Peabody Picture Vocabulary Test–Fourth Edition scores best discriminated children in the 2 classrooms. Conclusion African American children across gifted and general education classrooms produce fictional narratives of similar length, lexical diversity, and syntax complexity. However, African American children in gifted education classrooms may produce lower rates of AAE and perform better on standard measures of vocabulary than those in general education classrooms. PMID:25409770

  17. Naturalistic Action Performance Distinguishes Amnestic Mild Cognitive Impairment from Healthy Aging.

    PubMed

    Gold, David A; Park, Norman W; Murphy, Kelly J; Troyer, Angela K

    2015-07-01

    Individuals with amnestic mild cognitive impairment (aMCI) show minor decrements in their instrumental activities of daily living (IADL). Sensitive measures of IADL performance are needed to capture the mild difficulties observed in aMCI groups. Routine naturalistic actions (NAs) are familiar IADL-type activities that require individuals to enact everyday tasks such as preparing coffee. In the current study we examined the extent to which NAs could be used to help facilitate differential diagnosis of aMCI relative to composite measures of episodic memory, semantic knowledge, and executive function. Healthy older adults (n=24) and individuals with aMCI (n=24) enacted two highly familiar NAs and completed tests of episodic memory, semantic knowledge, and executive function. Binary logistic regression was used to predict group membership (aMCI vs. control participants). The regression analyses indicated that NA performance could reliably predict group membership, over and above measures of cognitive functioning. These findings indicated that NA performance can be used to help facilitate differential diagnosis of healthy aging and aMCI and used as an outcome measure in intervention studies.

  18. A unique combination of micronutrients rejuvenates cognitive performance in aged mice.

    PubMed

    Perez, Sam D; Du, Kristy; Rendeiro, Catarina; Wang, Lin; Wu, Qian; Rubakhin, Stanislav S; Vazhappilly, Rema; Baxter, Jeffrey H; Sweedler, Jonathan V; Rhodes, Justin S

    2017-03-01

    It is widely believed that diet can influence the onset and severity of cognitive aging, but the optimal combination of micronutrients and molecular and cellular mechanisms remain elusive. The purpose of this study was to compare the effects of eight distinct diets, consisting of various concentrations of selected micronutrients, on learning and memory as well as markers of neuronal plasticity, and metabolic and neuro-immune status of the aged hippocampus. Eighteen-month-old male and female C57BL/6J mice were fed the diets for 16 weeks, followed by learning and memory trials on the active avoidance task. Number of immature neurons were measured by immunohistochemical detection of doublecortin (DCX(+)) in the granule layer of the dentate gyrus. Amount of mitochondrial DNA (mtDNA) and gene expression of molecular markers of mitochondrial biogenesis (Ppargc1α, Sirt1, Tfam), and neuroinflammation (IL-10, Alox15, Ptgs2, IL-1β, IL-6 and Tnf) were assessed by quantitative real time polymerase chain reaction (qRT-PCR) of hippocampal samples. Tissue levels of selected micronutrients and a number of metabolites were measured by liquid chromatography-mass spectrometry. The diet supplemented with RRR d-alpha tocopheryl acetate, citicholine, 5-methyltetrahydrofolic acid, quercetin and the n-3 fatty acid phosphatidylserine-docosahexaenoic acid, improved performance on the active avoidance learning and memory task compared to all the other less-complex diets. This diet also increased IL-10 expression and attenuated the age-related change in mtDNA content in the hippocampus without affecting metabolite levels. Results suggest cognitive benefits of wholesome diets are partially mediated through combined antioxidant and anti-inflammatory activities of optimized mixtures of micronutrients.

  19. Somatic, Endurance Performance and Heart Rate Variability Profiles of Professional Soccer Players Grouped According to Age

    PubMed Central

    Botek, Michal; McKune, Andrew J.; Klimešová, Iva

    2016-01-01

    Abstract This cross-sectional study compared somatic, endurance performance determinants and heart rate variability (HRV) profiles of professional soccer players divided into different age groups: GI (17–19.9 years; n = 23), GII (20–24.9 years; n = 45), GIII (25–29.9 years; n = 30), and GIV (30–39 years; n = 26). Players underwent somatic and HRV assessment and maximal exercise testing. HRV was analyzed by spectral analysis of HRV, and high (HF) and low (LF) frequency power was transformed by a natural logarithm (Ln). Players in GIV (83 ± 7 kg) were heavier (p < 0.05) compared to both GI (73 ± 6 kg), and GII (78 ± 6 kg). Significantly lower maximal oxygen uptake (VO2max, ml•kg-1•min-1) was observed for GIV (56.6 ± 3.8) compared to GI (59.6 ± 3.9), GII (59.4 ± 4.2) and GIV (59.7 ± 4.1). All agegroups, except for GII, demonstrated comparable relative maximal power output (Pmax). For supine HRV, significantly lower Ln HF (ms2) was identified in both GIII (7.1 ± 0.8) and GIV (6.9 ± 1.0) compared to GI (7.9 ± 0.6) and GII (7.7 ± 0.9). In conclusion, soccer players aged >25 years showed negligible differences in Pmax unlike the age group differences demonstrated in VO2max. A shift towards relative sympathetic dominance, particularly due to reduced vagal activity, was apparent after approximately 8 years of competing at the professional level. PMID:28031758

  20. Age-related changes in cardiovascular performance in mitral regurgitation: analysis of 61 patients.

    PubMed

    Clancy, K F; Iskandrian, A S; Hakki, A H; Nestico, P; DePace, N L

    1985-03-01

    This study examines the cardiovascular performance in relation to age in 61 patients with moderate or severe chronic mitral regurgitation (MR). Coronary artery disease (CAD) (50% or more diameter narrowing of one or more major coronary arteries) was present in 20 patients (33%). Patients less than 60 years (n = 33) had lower pulmonary artery pressure, systolic arterial pressure, left ventricular (LV) end-diastolic pressure, and pulmonary artery wedge pressure than the patients greater than or equal to 60 years (n = 28) (p less than 0.05). In the 41 patients without associated CAD, the LV end-diastolic pressure and systemic arterial pressure were higher in patients greater than or equal to 60 years (n = 14) than patients less than 60 years (n = 27) (p less than 0.05). The LV end-diastolic pressure showed an age-related increase in the presence or absence of CAD. Thus, older patients with MR have higher LV end-diastolic pressure, probably because of an increase in myocardial stiffness.

  1. Influence of sludge age on the performance of MFC treating winery wastewater.

    PubMed

    Penteado, Eduardo D; Fernandez-Marchante, Carmen Maria; Zaiat, Marcelo; Cañizares, Pablo; Gonzalez, Ernesto Rafael; Rodrigo, Manuel Andrés

    2016-05-01

    The objective of this paper was to determine the influence of sludge age on microbial fuel cell (MFC) performance for generating electricity and removing organic matter from winery wastewater. Six Solid Retention Times (SRT) were used: 1.2, 1.4, 1.8, 2.3, 3.5 and 7.0 d. Results demonstrate that the electricity generation increases by decreasing the SRT, selecting electrogenic microorganisms, once the specific organic loading rate (SOLR) increased and the competition for substrate was reduced. Decreasing the SRT, coulombic efficiency can be increased from 3.4% to almost 42.2% and maximum power density from 58 to 890 mW m(-2). However the SRT did not influence on organic matter removal in biological treatment, because only a small part of COD was removed oscillating around 600 mg L(-1) d(-1)and it was very similar at all SRT studied.

  2. Spatial learning and psychomotor performance of C57BL/6 mice: age sensitivity and reliability of individual differences.

    PubMed

    de Fiebre, Nancyellen C; Sumien, Nathalie; Forster, Michael J; de Fiebre, Christopher M

    2006-09-01

    Two tests often used in aging research, the elevated path test and the Morris water maze test, were examined for their application to the study of brain aging in a large sample of C57BL/6JNia mice. Specifically, these studies assessed: (1) sensitivity to age and the degree of interrelatedness among different behavioral measures derived from these tests, (2) the effect of age on variation in the measurements, and (3) the reliability of individual differences in performance on the tests. Both tests detected age-related deficits in group performance that occurred independently of each other. However, analysis of data obtained on the Morris water maze test revealed three relatively independent components of cognitive performance. Performance in initial acquisition of spatial learning in the Morris maze was not highly correlated with performance during reversal learning (when mice were required to learn a new spatial location), whereas performance in both of those phases was independent of spatial performance assessed during a single probe trial administered at the end of acquisition training. Moreover, impaired performance during initial acquisition could be detected at an earlier age than impairments in reversal learning. There were modest but significant age-related increases in the variance of both elevated path test scores and in several measures of learning in the Morris maze test. Analysis of test scores of mice across repeated testing sessions confirmed reliability of the measurements obtained for cognitive and psychomotor function. Power calculations confirmed that there are sufficiently large age-related differences in elevated path test performance, relative to within age variability, to render this test useful for studies into the ability of an intervention to prevent or reverse age-related deficits in psychomotor performance. Power calculations indicated a need for larger sample sizes for detection of intervention effects on cognitive components of the

  3. Elevated manganese and cognitive performance in school-aged children and their mothers

    SciTech Connect

    Menezes-Filho, Jose A.; Novaes, Cristiane de O.; Moreira, Josino C.; Sarcinelli, Paula N.; Mergler, Donna

    2011-01-15

    Background: Growing evidence suggests that excess manganese (Mn) in children is associated with neurobehavioral impairments. In Brazil, elevated hair Mn concentrations were reported in children living near a ferro-manganese alloy plant. Objectives: We investigated these children's and caregivers' cognitive function in relation to bioindicators of Mn exposure. Methods: In this cross-sectional study, the WISC-III was administered to 83 children aged between 6 and 12 years; the Raven Progressive Matrix was administered to the primary caregivers (94% mothers), who likewise responded to a questionnaire on socio demographics and birth history. Mn in hair (MnH) and blood (MnB) and blood lead (PbB) were measured by graphite furnace atomic absorption spectrometry (GFAAS). Results: Children's mean MnB and MnH were 8.2 {mu}g/L (2.7-23.4) and 5.83 {mu}g/g (0.1-86.68), respectively. Mean maternal MnH was 3.50 {mu}g/g (0.10-77.45) and correlated to children's MnH (rho=0.294, p=0.010). Children's MnH was negatively related to Full-Scale Intelligence Quotient (IQ) and Verbal IQ; {beta} coefficients for MnH were -5.78 (95% CI -10.71 to -0.21) and -6.72 (-11.81 to -0.63), adjusted for maternal education and nutritional status. Maternal MnH was negatively associated with performance on the Raven's ({beta}=-2.69, 95% CI -5.43 to 0.05), adjusted for education years, family income and age. Conclusions: These findings confirm that high MnH in children is associated with poorer cognitive performance, especially in the verbal domain. Primary caregiver's IQ is likewise associated to Mn exposure, suggesting that, in this situation, children's cognition may be affected directly and indirectly by Mn exposure.

  4. Iron Level and Myelin Content in the Ventral Striatum Predict Memory Performance in the Aging Brain

    PubMed Central

    Weiskopf, Nikolaus

    2016-01-01

    Age-related memory impairments have been associated with structural changes in the dopaminergic system, but the underlying mechanisms remain unclear. Recent work indicates that iron accumulation might be of particular relevance. As iron accumulates, a degeneration of myelin sheaths has been observed in the elderly, but the relationship between both and their impact on memory performance in healthy elderly humans remain important open questions. To address this issue, we combined an established behavioral paradigm to test memory performance [verbal learning memory test (VLMT)] with state of the art quantitative magnetic resonance imaging techniques allowing us to quantify the degree of myelination and iron accumulation via markers of tissue microstructure in a group of young (18–32 years) and healthy elderly humans (55–79 years). As expected, we observed a decrease in gray matter volume and myelin, and an increase of iron in the elderly relative to the young subjects within widespread brain regions, including the basal ganglia. Furthermore, higher levels of iron within the ventral striatum were accompanied by a negative correlation between myelin and iron specific for the elderly participants. Importantly, both markers of iron and myelin (and their ratio) predicted the performance of the elderly in the VLMT. This suggests that ventral striatum iron accumulation is linked to demyelination and impairments in declarative memory. Together, our data provide novel insights into underlying microstructural mechanisms of memory decline in the elderly. SIGNIFICANCE STATEMENT Memory decline in healthy elderly is a common phenomenon, but the underlying neural mechanisms remain unclear. We used a novel approach that allowed us to combine behavior and whole-brain measures of iron, myelin, and gray matter in the participant's individual subspace to analyze structure–structure and structure–behavior interactions. We were able to show, that age-related high levels of iron

  5. Storage and Aging Effects on Spherical Resorcinol-Formaldehyde Resin Ion Exchange Performance

    SciTech Connect

    Fiskum, Sandra K.; Arm, Stuart T.; Edwards, Matthew K.; Steele, Marilyn J.; Thomas, Kathie K.

    2007-09-10

    Bechtel National, Inc. (BNI) is evaluating the alternate Cs ion exchanger, spherical resorcinol-formaldehyde (RF), for use in the River Protection Project-Waste Treatment Plant (RPP-WTP).( ) Previous test activities with spherical RF indicate that it has adequate capacity, selectivity, and kinetics to perform in the plant according to the flowsheet needs. It appears to have better elution and hydraulic properties than the existing alternatives: ground-gel RF and SuperLig® 644 (SL 644).( ) To date, the spherical RF performance testing has been conducted on freshly manufactured resin (within ~2 months of manufacture). The ion exchange resins will be manufactured and shipped to the WTP up to 1 year before being used in the plant. Changes in the resin properties during storage could reduce the capacity of the resin to remove Cs from low-activity waste solutions. Active sites on organic SL-644 resin have been shown to degrade during storage (Arm et al. 2004). Additional testing was needed to study the effects of storage conditions and aging on spherical RF ion exchange performance. Variables that could have a significant impact on ion exchange resins during storage include storage temperature, medium, and time. Battelle—Pacific Northwest Division (PNWD) was contracted to test the effects of various storage conditions on spherical RF resin. Data obtained from the testing will be used by the WTP operations to provide direction for suitable storage conditions and manage the spherical RF resin stock. Storage test conditions included wet and dry resin configurations under nitrogen at three temperatures. Work was initially conducted under contract number 24590-101-TSA-W000-00004 satisfying the needs defined in Appendix C of the Research and Technology Plan( ) TSS A-219 to evaluate the impact of storage conditions on RF resin performance. In February 2007, the contract mechanism was switched to Pacific Northwest National Laboratory (PNNL) Operating Contract DE-AC05-76RL

  6. College Students' Perceptions of Job Demands, Recommended Retirement Ages, and Age of Optimal Performance in Selected Occupations

    ERIC Educational Resources Information Center

    Panek, Paul E.; Staats, Sara; Hiles, Amanda

    2006-01-01

    Two studies were conducted. In study one 100 participants rated 60 occupations on the amount of cognitive/intellectual, physical, sensory-perceptual, and perceptual-motor demands they perceived as required for successful performance in that particular occupation. Results of a cluster analysis determined four clusters of occupations on the basis of…

  7. Neuropsychological Performance in Polyconsumer Men Under Treatment. Influence of Age of Onset of Substance Use

    PubMed Central

    Capella, Maria del Mar; Benaiges, Irina; Adan, Ana

    2015-01-01

    Neurocognition is a key factor in the development and maintenance of Substance Use Disorders (SUD). However, there are still several aspects that need to be studied in this area. In this study, we elucidate the influence of age of onset of substance use (OSU) on the clinical course and neuropsychological performance of substance use disorder (SUD) patients, as well as to explore the influence of years of education, duration of drug use and premorbid intelligence quotient (IQ) on the cognitive results obtained. An exhaustive neuropsychological battery was used to assess different cognitive domains in 80 male polyconsumers, 41 with earlier OSU (16 years or before: OSU ≤ 16) and 39 with later OSU (17 years or later: OSU ≥ 17). The patients were under treatment with at least 4 months of abstinence confirmed by urinalysis. The OSU ≤ 16 group presented a worse clinical state, as well as a lower premorbid IQ and worse performance in processing speed, visual perception and planning skills. The duration of drug use may account for the differences in planning and processing speed. In this work we discuss the premorbid or acquired nature of the cognitive deficits found. PMID:26155725

  8. Functional handwriting performance in school-age children with fetal alcohol spectrum disorders.

    PubMed

    Duval-White, Cherie J; Jirikowic, Tracy; Rios, Dianne; Deitz, Jean; Olson, Heather Carmichael

    2013-01-01

    Handwriting is a critical skill for school success. Children with fetal alcohol spectrum disorders (FASD) often present with fine motor and visual-motor impairments that can affect handwriting performance, yet handwriting skills have not been systematically investigated in this clinical group. This study aimed to comprehensively describe handwriting skills in 20 school-age children with FASD. Children were tested with the Process Assessment of the Learner, 2nd Edition (PAL-II), and the Visuomotor Precision subtest of NEPSY, a developmental neuropsychological assessment. Participants performed below average on PAL-II measures of handwriting legibility and speed and on NEPSY visual-motor precision tasks. In contrast, PAL-II measures of sensorimotor skills were broadly within the average range. Results provide evidence of functional handwriting challenges for children with FASD and suggest diminished visual-motor skills and increased difficulty as task complexity increases. Future research is needed to further describe the prevalence and nature of handwriting challenges in this population.

  9. Effects of combined strength and endurance training on treadmill load carrying walking performance in aging men.

    PubMed

    Holviala, Jarkko; Häkkinen, Arja; Karavirta, Laura; Nyman, Kai; Izquierdo, Mikel; Gorostiaga, Esteban M; Avela, Janne; Korhonen, Janne; Knuutila, Veli-Pekka; Kraemer, William J; Häkkinen, Keijo

    2010-06-01

    The present study examined the effects of twice weekly total body strength training (ST), endurance cycling (ET), and combined ST and ET (2+2 times a week) (SET) training on the load carrying walking test performance on the treadmill (TM) and changes in neuromuscular and endurance performance during a 21-week training period in aging men. Forty healthy men (54.8+/-8.0 years) were divided into 3 training groups (ET n=9, ST n=11, SET n=11) and a control group (C, n=9). Peak oxygen uptake (VO2peak), heart rate, and blood lactate concentration were measured before and after a 21-week training program using a graded TM and maximal incremental bicycle ergometer (BE) tests. Isometric forces, vertical jump, and electromyographic activity of leg extensor and/or forearm flexor (F) muscles were measured before and after training and the TM tests. Increases of 20-21% in strength and of 7-12% in cycling BE VO2peak occurred in the training groups, whereas the changes of C remained minor. VO2peak was associated, both before and after training, with TM exercise time in all groups (from r=0.65, p=0.030 to r=0.93, p<0.001). Only SET showed a significant training-induced increase (p=0.011) in exercise time of the TM walking with no significant increase in TM VO2peak. The present data suggest that in older men ET and SET induced specific increases in BE VO2peak and ST and SET in strength. However, only SET increased walking exercise time indicating improved load carrying walking performance because of large individual differences in the magnitude of the development of either strength or endurance capacities.

  10. Influence of age and sex on line bisection: a study of normal performance with implications for visuospatial neglect.

    PubMed

    Varnava, Alice; Halligan, Peter W

    2007-11-01

    Line bisection is an established clinical task used to diagnose visuospatial neglect. To date, few studies have considered the extent to which age and sex as background variables contribute to bisection performance. Both variables affect the neural substrates underlying cognitive processes and hence the behavioural performance of bisection. The purpose of this study was to examine the effects of age and sex on normal bisection performance, using three different line lengths to elucidate the influence of these potential contributing factors. Seventy men and 70 women, divided equally into seven age-cohorts between 14 and 80 years, bisected lines. Results indicated clear age- and sex-related differences both in the magnitude and direction of bisection deviations across the three line lengths. Differences are discussed in terms of neural changes across the adult lifespan including hemispheric differences and hormonally mediated changes.

  11. "Life Stage-Specific" Variations in Performance in Response to Age Stereotypes

    ERIC Educational Resources Information Center

    Hehman, Jessica A.; Bugental, Daphne Blunt

    2013-01-01

    In a test of life stage-specific responses to age-based stigma, older (n = 54, ages 62-92) and younger (n = 81, ages 17-22) adults were told that a task (Weschler Adult Intelligence Scale-III block design) required either (a) speed/contemporary knowledge (YA; "youth advantage") or (b) life experience/wisdom (OA; "age…

  12. Elevated manganese and cognitive performance in school-aged children and their mothers

    PubMed Central

    Menezes-Filho, José A.; Novaes, Cristiane de O.; Moreira, Josino C.; Sarcinelli, Paula N.; Mergler, Donna

    2010-01-01

    Background Growing evidence suggests that excess manganese (Mn) in children is associated with neurobehavioral impairments. In Brazil, elevated hair Mn concentrations were reported in children living near a ferro-manganese alloy plant. Objectives We investigated these children’s and caregivers’ cognitive function in relation to bioindicators of Mn exposure. Methods In this cross-sectional study, the WISC-III was administered to 83 children aged between 6 and 12 years; the Raven Progressive Matrix was administered to the primary caregivers (94% mothers), who likewise responded to a questionnaire on socio demographics and birth history. Mn in hair (MnH) and blood (MnB) and blood lead (PbB) were measured by graphite furnace atomic absorption spectrometry (GFAAS). Results Children’s mean MnB and MnH were 8.2 µg/L (2.7 – 23.4) and 5.83 µg/g (0.1 −86.68), respectively. Mean maternal MnH was 3.50 µg/g (0.10 – 77.45) and correlated to children’s MnH (rho=0.294, p=0.010). Children’s MnH was negatively related to Full-Scale Intelligence Quotient (IQ) and Verbal IQ; β coefficients for MnH were −5.78 (95% CI −10.71 to −0.21) and −6.72 (−11.81 to −0.63), adjusted for maternal education and nutritional status. Maternal MnH was negatively associated with performance on the Raven’s (β = −2.69, 95% CI −5.43 to 0.05), adjusted for education years, family income and age. Conclusions These findings confirm that high MnH in children is associated with poorer cognitive performance, especially in the verbal domain. Primary caregiver’s IQ is likewise associated to Mn exposure, suggesting that, in this situation, children’s cognition may be affected directly and indirectly by Mn exposure. PMID:20943219

  13. How Strong and Weak Readers Perform on the Developmental Eye Movement Test (DEM): Norms for Latvian School-Aged Children

    ERIC Educational Resources Information Center

    Serdjukova, Jelena; Ekimane, Lasma; Valeinis, Janis; Skilters, Jurgis; Krumina, Gunta

    2017-01-01

    The aim of our study was to determine DEM test performance norms for school-aged children in Latvia, assess how DEM test results correlate with children's reading rates, compare test performance between strong and weak readers. A modified DEM test and a newly developed reading test were administered to 1487 children during a screening survey. Our…

  14. Load-related brain activation predicts spatial working memory performance in youth aged 9-12 and is associated with executive function at earlier ages.

    PubMed

    Huang, Anna S; Klein, Daniel N; Leung, Hoi-Chung

    2016-02-01

    Spatial working memory is a central cognitive process that matures through adolescence in conjunction with major changes in brain function and anatomy. Here we focused on late childhood and early adolescence to more closely examine the neural correlates of performance variability during this important transition period. Using a modified spatial 1-back task with two memory load conditions in an fMRI study, we examined the relationship between load-dependent neural responses and task performance in a sample of 39 youth aged 9-12 years. Our data revealed that between-subject differences in task performance was predicted by load-dependent deactivation in default network regions, including the ventral anterior cingulate cortex (vACC) and posterior cingulate cortex (PCC). Although load-dependent increases in activation in prefrontal and posterior parietal regions were only weakly correlated with performance, increased prefrontal-parietal coupling was associated with better performance. Furthermore, behavioral measures of executive function from as early as age 3 predicted current load-dependent deactivation in vACC and PCC. These findings suggest that both task positive and task negative brain activation during spatial working memory contributed to successful task performance in late childhood/early adolescence. This may serve as a good model for studying executive control deficits in developmental disorders.

  15. The Use of Bayesian Latent Class Cluster Models to Classify Patterns of Cognitive Performance in Healthy Ageing

    PubMed Central

    Cunha, Pedro; Palha, Joana Almeida; Sousa, Nuno

    2013-01-01

    The main focus of this study is to illustrate the applicability of latent class analysis in the assessment of cognitive performance profiles during ageing. Principal component analysis (PCA) was used to detect main cognitive dimensions (based on the neurocognitive test variables) and Bayesian latent class analysis (LCA) models (without constraints) were used to explore patterns of cognitive performance among community-dwelling older individuals. Gender, age and number of school years were explored as variables. Three cognitive dimensions were identified: general cognition (MMSE), memory (MEM) and executive (EXEC) function. Based on these, three latent classes of cognitive performance profiles (LC1 to LC3) were identified among the older adults. These classes corresponded to stronger to weaker performance patterns (LC1>LC2>LC3) across all dimensions; each latent class denoted the same hierarchy in the proportion of males, age and number of school years. Bayesian LCA provided a powerful tool to explore cognitive typologies among healthy cognitive agers. PMID:23977183

  16. Beta-hydroxy-beta-methylbutyrate (HMB) ameliorates age-related deficits in water maze performance, especially in male rats.

    PubMed

    Kougias, Daniel G; Hankosky, Emily R; Gulley, Joshua M; Juraska, Janice M

    2017-03-01

    Beta-hydroxy-beta-methylbutyrate (HMB) is commonly supplemented to maintain muscle in elderly and clinical populations and has potential as a nootropic. Previously, we have shown that in both male and female rats, long-term HMB supplementation prevents age-related dendritic shrinkage within the medial prefrontal cortex (mPFC) and improves cognitive flexibility and working memory performance that are both age- and sex-specific. In this study, we further explore the cognitive effects by assessing visuospatial learning and memory with the Morris water maze. Female rats were ovariectomized at 11months of age to model human menopause. At 12months of age, male and female rats received relatively short- or long-term (1- or 7-month) dietary HMB (450mg/kg/dose) supplementation twice a day prior to testing. Spatial reference learning and memory was assessed across four days in the water maze with four trials daily and a probe trial on the last day. Consistent with previous work, there were age-related deficits in water maze performance in both sexes. However, these deficits were ameliorated in HMB-treated males during training and in both sexes during probe trial performance. Thus, HMB supplementation prevented the age-related decrement in water maze performance, especially in male rats.

  17. Aging model for solid lubricants used in weapon stronglinks: tribological performance and hardware review

    SciTech Connect

    Dugger, M.T.; Peebles, D.E.; Sorroche, E.H.; Varga, K.S.; Bryan, R.M.

    1997-09-01

    The solid lubricant used most extensively in strong links throughout the enduring stockpile contains MoS{sub 2}, which is known to react with oxygen and water vapor resulting in a change in the material`s friction and wear behavior. The authors have examined the frictional behavior of this lubricant as a function of oxidation, in support of efforts to quantify the impact of changes in the material on the dynamic behavior of the MC2969 strong link. Their results show that the friction response of oxidized lubricant is strongly influenced by the amount of burnishing performed on the lubricant after deposition. Low levels of burnish leave a thick film, of which only the near surface degrades during oxidation. Rapid wear of the oxidized material leaves a surface whose properties are the same as non-oxidized material. Higher levels of burnish leave a thinner film of lubricant such that the entire film may be oxidized. The friction coefficient on this surface reaches a steady state value greater than that of non oxidized material. In addition to these fundamental differences in steady state behavior, they have shown that the initial friction coefficient on oxidized surfaces is related to the amount of sulfide converted to sulfate, regardless of the oxidation conditions used. Measurements on parts returned from the stockpile show that the friction behavior of aged hardware is consistent with the behavior observed on controlled substrates containing thin lubricant films.

  18. Effect of aging on EPR cable electrical performance during LOCA simulations. [Ethylene propylene rubber

    SciTech Connect

    Bustard, L.D.

    1984-01-01

    When exposed to a LOCA environment, some ethylene propylene rubber (EPR) cable materials experience substantial moisture absorption and dimensional changes. These phenomena may contribute to mechanical damage of the cable insulation resulting in electrical degradation. Recent experiments illustrate that the extent of moisture absorption and dimensional changes during an accident simulation are dependent on the EPR product, the accelerated age, and the aging technique employed to achieve that age. Results for several commercial EPR materials are summarized.

  19. Outside of the laboratory: Associations of working-memory performance with psychological and physiological arousal vary with age.

    PubMed

    Riediger, Michaela; Wrzus, Cornelia; Klipker, Kathrin; Müller, Viktor; Schmiedek, Florian; Wagner, Gert G

    2014-03-01

    We investigated age differences in associations among self-reported experiences of tense and energetic arousal, physiological activation indicated by heart rate, and working-memory performance in everyday life. The sample comprised 92 participants aged 14-83 years. Data were collected for 24 hr while participants pursued their normal daily routines. Participants wore an ambulatory biomonitoring system that recorded their cardiac and physical activity. Using mobile phones as assessment devices, they also provided an average of 7 assessments of their momentary experiences of tense arousal (feeling nervous) and energetic arousal (feeling wide-awake) and completed 2 trials of a well-practiced working-memory task. Experiences of higher energetic arousal were associated with higher heart rate in participants younger than 50 years of age but not in participants older than that, and energetic arousal was unrelated to within-person fluctuations in working-memory performance. Experiences of tense arousal were associated with higher heart rate independent of participants' age. Tense arousal and physiological activation were accompanied by momentary impairments in working-memory performance in middle-aged and older adults but not in younger individuals. Results suggest that psychological arousal experiences are associated with lower working-memory performance in middle-aged and older adults when they are accompanied by increased physiological activation and that the same is true for physiological activation deriving from other influences. Hence, age differences in cognitive performance may be exaggerated when the assessment situation itself elicits tense arousal or occurs in situations with higher physiological arousal arising from affective experiences, physical activity, or circadian rhythms.

  20. Age differences in short-term memory binding are related to working memory performance across the lifespan.

    PubMed

    Fandakova, Yana; Sander, Myriam C; Werkle-Bergner, Markus; Shing, Yee Lee

    2014-03-01

    Memory performance increases during childhood and adolescence, and decreases in old age. Among younger adults, better ability to bind items to the context in which they were experienced is associated with higher working memory performance (Oberauer, 2005). Here, we examined the extent to which age differences in binding contribute to life span age differences in short-term memory (STM). Younger children (N = 85; 10 to 12 years), teenagers (N = 41; 13 to 15 years), younger adults (N = 84; 20 to 25 years), and older adults (N = 86; 70 to 75 years) worked on global and local short-term recognition tasks that are assumed to measure item and item-context memory, respectively. Structural equation models showed that item-context bindings are functioning less well in children and older adults compared with younger adults and teenagers. This result suggests protracted development of the ability to form and recollect detailed short-term memories, and decline of this ability in aging. Across all age groups, better item-context binding was associated with higher working memory performance, indicating that developmental differences in binding mechanisms are closely related to working memory development in childhood and old age.

  1. Increase in participation but decrease in performance in age group mountain marathoners in the 'Jungfrau Marathon': a Swiss phenomenon?

    PubMed

    Knechtle, Beat; Rosemann, Thomas; Zingg, Matthias A; Rüst, Christoph A

    2015-01-01

    Participation and performance trends for age group marathoners have been investigated for large city marathons such as the 'New York City Marathon' but not for mountain marathons. This study investigated participation and trends in performance and sex difference in the mountain marathon 'Jungfrau Marathon' held in Switzerland from 2000 to 2014 using single and mixed effects regression analyses. Results were compared to a city marathon (Lausanne Marathon) also held in Switzerland during the same period. Sex difference was calculated using the equation ([race time in women] - [race time in men]/[race time in men] × 100). Changes in sex differences across calendar years and were investigated using linear regression models. In 'Jungfrau Marathon', participation in all female and male age groups increased with exception of women in age groups 18-24 and men in age groups 30-34, 40-44 and 60-64 years where participation remained unchanged. In 'Lausanne Marathon', participation increased in women in age groups 30-34 to 40-44 years. In men, participation increased in age groups 25-29 to 44-44 years and 50-54 years. In 'Jungfrau Marathon' runners became slower across years in age groups 18-24 to 70-74 years. In 'Lausanne Marathon', runners became slower across years in age groups 18-24 and 30-34 to 65-69 years, but not for 25-29, 70-74 and 75-79 years. In 'Jungfrau Marathon', sex difference increased in age groups 25-29 (from 4 to 10 %) and 60-64 years (from 3 to 8 %) but decreased in age group 40-44 years (from 12 to 6 %). In 'Lausanne Marathon', the sex difference showed no changes. In summary, participation increased in most female and male age groups but performance decreased in most age groups for both the mountain marathon 'Jungfrau Marathon' and the city marathon 'Lausanne Marathon'. The sex differences were lower in the 'Jungfrau Marathon' (~6-7 %) compared to the 'Lausanne Marathon' where the sex difference was ~10-12 % from age groups 18-24 to 55

  2. Age differences in behavioral and neural correlates of proactive interference: Disentangling the role of overall working memory performance.

    PubMed

    Loosli, Sandra V; Rahm, Benjamin; Unterrainer, Josef M; Mader, Irina; Weiller, Cornelius; Kaller, Christoph P

    2016-02-15

    Reliable performance in working memory (WM) critically depends on the ability to resist proactive interference (PI) from previously relevant WM contents. Both WM performance and PI susceptibility are subject to cognitive decline at older adult age. However, the behavioral and neural processes underlying these co-evolving developmental changes and their potential interdependencies are not yet understood. Here, we investigated PI using a recent-probes WM paradigm and functional MRI in a cross-sectional sample of younger (n=18, 10 female, 23.4 ± 2.7 years) and older adults (n=18, 10 female, 70.2 ± 2.7 years). As expected, older adults showed lower WM performance and higher PI susceptibility than younger adults. Resolution of PI activated a mainly bilateral frontal network across all participants. Significant interactions with age indicated reduced neural activation in older adults for PI resolution. A second analysis in a selection of younger and older adults (n=12 each) with matched WM performance also revealed significant differences in PI between both age groups and - on a descriptive level - again a hypo-activation of the older adults' PI network. But the differential effect of age on the neural PI effects did not reach significance in this smaller sample most likely to the reduced statistical power. However, given the highly similar patterns in both the overall and the WM-matched samples, we propose that the hypo-activation of the PI network in the older adults may not be attributable to age-related differences in overall WM performance, hence suggesting that higher PI susceptibility in older adult age does not directly depend on their lower WM performance.

  3. Improving tribological performance of gray cast iron by laser peening in dynamic strain aging temperature regime

    NASA Astrophysics Data System (ADS)

    Feng, Xu; Zhou, Jianzhong; Mei, Yufen; Huang, Shu; Sheng, Jie; Zhu, Weili

    2015-09-01

    A high and stable brake disc friction coefficient is needed for automobile safety, while the coefficient degrades due to elevated temperature during the braking process. There is no better solution except changes in material composition and shape design optimization. In the dynamic strain aging(DSA) temperature regime of gray cast iron, micro-dimples with different dimple depth over diameter and surface area density are fabricated on the material surface by laser peening(LP) which is an LST method. Friction behavior and wear mechanism are investigated to evaluate the effects of surface texturing on the tribological performance of specimens under dry conditions. Through LP impacts assisted by DSA, the friction coefficients of the LPed specimens increase noticeably both at room temperature and elevated temperature in comparison to untreated specimens. Moreover, the coefficient of specimen with dimple depth over diameter of 0.03 and surface area density of 30% is up to 0.351 at room temperature, which dramatically rises up to 1.33 times that of untextured specimen and the value is still up to 0.3305 at 400°C with an increasing ratio of 35% compared to that of untreated specimen. The surface of textured specimen shows better wear resistance compared to untreated specimen. Wear mechanism includes adhesive wear, abrasive wear and oxidation wear. It is demonstrated that LP assisted by DSA can substantially improve wear resistance, raise the friction coefficient as well as its stability of gray cast iron under elevated temperatures. Heat fade and premature wear can be effectively relieved by this surface modification method.

  4. Age Differences in Perseveration: Cognitive and Neuroanatomical Mediators of Performance on the Wisconsin Card Sorting Test

    ERIC Educational Resources Information Center

    Head, Denise; Kennedy, Kristen M.; Rodrigue, Karen M.; Raz, Naftali

    2009-01-01

    Aging effects on the Wisconsin Card Sorting Test (WCST) are fairly well established but the mechanisms of the decline are not clearly understood. In this study, we examined the cognitive and neural mechanisms mediating age-related increases in perseveration on the WCST. MRI-based volumetry and measures of selected executive functions in…

  5. Contrasting Effects of Starting Age and Input on the Oral Performance of Foreign Language Learners

    ERIC Educational Resources Information Center

    Muñoz, Carmen

    2014-01-01

    The present study focuses on the influence of starting age and input on foreign language learning. In relation to starting age, the study investigates whether early starters in instructional settings achieve the same kind of long-term advantage as learners in naturalistic settings and it complements previous research by using data from oral…

  6. Experience-Based Mitigation of Age-Related Performance Declines: Evidence from Air Traffic Control

    ERIC Educational Resources Information Center

    Nunes, Ashley; Kramer, Arthur F.

    2009-01-01

    Previous research has found age-related deficits in a variety of cognitive processes. However, some studies have demonstrated age-related sparing on tasks where individuals have substantial experience, often attained over many decades. Here, the authors examined whether decades of experience in a fast-paced demanding profession, air traffic…

  7. Aging and Cognitive Performance: Challenges and Implications for Physicians Practicing in the 21st Century

    ERIC Educational Resources Information Center

    Durning, Steven J.; Artino, Anthony R.; Holmboe, Eric; Beckman, Thomas J.; van der Vleuten, Cees; Schuwirth, Lambert

    2010-01-01

    The demands of physician practice are growing. Some specialties face critical shortages and a significant percentage of physicians are aging. To improve health care it is paramount to understand and address challenges, including cognitive issues, facing aging physicians. In this article, we outline several issues related to cognitive performance…

  8. Effects of 8-Week Training on Aerobic Capacity and Swimming Performance of Boys Aged 12 Years

    ERIC Educational Resources Information Center

    Zarzeczny, Ryszard; Kuberski, Mariusz; Deska, Agnieszka; Zarzeczna, Dorota; Rydz, Katarzyna; Lewandowska, Anna; Balchanowski, Tomasz; Bosiacki, Janusz

    2011-01-01

    Study aim: To assess the effects of 8-week endurance training in swimming on work capacity of boys aged 12 years. Material and methods: The following groups of schoolboys aged 12 years were studied: untrained control (UC; n = 14) and those training swimming for two years. The latter ones were subjected to 8-week training in classical style (CS; n…

  9. Cerebral White Matter Integrity Mediates Adult Age Differences in Cognitive Performance

    ERIC Educational Resources Information Center

    Madden, David J.; Spaniol, Julia; Costello, Matthew C.; Bucur, Barbara; White, Leonard E.; Cabeza, Roberto; Davis, Simon W.; Dennis, Nancy A.; Provenzale, James M.; Huettel, Scott A.

    2009-01-01

    Previous research has established that age-related decline occurs in measures of cerebral white matter integrity, but the role of this decline in age-related cognitive changes is not clear. To conclude that white matter integrity has a mediating (causal) contribution, it is necessary to demonstrate that statistical control of the white…

  10. The influence of maternal age and mating frequency on egg size and offspring performance in Callosobruchus maculatus (Coleoptera: Bruchidae).

    PubMed

    Fox, Charles W

    1993-10-01

    Maternal age influences offspring quality of many species of insects. This observed maternal age influence on offspring performance may be mediated through maternal age effects on egg size, which in turn may be directly influenced by the female's nutritional state. Thus, behaviors that influence a female's nutritional status will indirectly influence egg size, and possibly offspring life histories. Because males provide nutrients to females in their ejaculate, female mating frequency is one behavior which may influence her nutritional status, and thus the size of her eggs and the performance of her offspring. In this paper, I first quantify the influences of maternal age on egg size and offspring performance of the bruchid beetle, Callosobruchus maculatus. I then examine whether nutrients transferred during copulation reduce the magnitude of maternal age effects on egg size and larval performance when mothers are nutrient-stressed. Egg size and egg hatchability decreased, and development time increased, with increasing maternal age. Multiple mating and adult feeding by females both resulted in increased egg size. This increase in egg size of females mated multiply did not translate into reduced development time or increased body size and egg hatchability, but did correlate with improved survivorship of offspring produced by old mothers. Thus, it appears that because the influence of mating frequency on egg size is small relative to the influence of maternal age, the influence of nutrients derived from multiple mating on offspring life history is almost undetectable (detected only as a small influence on survivorship). For C. maculatus, female multiple mating has been demonstrated to increase adult female survivorship (Fox 1993a), egg production (Credland and Wright 1989; Fox 1993a), egg size, and larval survivorship, but, contrary to the suggestion of Wasserman and Asami (1985), multiple mating had no detectable influence on offspring development time or body size.

  11. Longitudinal study of performance on the Ruff Figural Fluency Test in persons aged 35 years or older.

    PubMed

    van Eersel, Marlise E A; Joosten, Hanneke; Koerts, Janneke; Gansevoort, Ron T; Slaets, Joris P J; Izaks, Gerbrand J

    2015-01-01

    The Ruff Figural Fluency Test (RFFT) is a cognitive test to measure executive function. Longitudinal studies have shown that repeated testing improves performance on the RFFT. Such a practice effect may hinder the interpretation of test results in a clinical setting. Therefore, we investigated the longitudinal performance on the RFFT in persons aged 35-82 years. Performance on the RFFT was measured three times over an average follow-up period of six years in 2,515 participants of the Prevention of REnal and Vascular ENd-stage Disease (PREVEND) study in Groningen, the Netherlands: 53% men; mean age (SD), 53 (10) years. The effect of consecutive measurements on performance on the RFFT was investigated with linear multilevel regression models that also included age, gender, educational level and the interaction term consecutive measurement number x age as independent variables. It was found that the mean (SD) number of unique designs on the RFFT increased from 73 (26) at the first measurement to 79 (27) at the second measurement and to 83 (26) at the third measurement (p<0.001). However, the increase per consecutive measurement number was negatively associated with age and decreased with 0.23 per one-year increment of age (p<0.001). The increase per consecutive measurement number was not dependent on educational level. Similar results were found for the median (IQR) number of perseverative errors which showed a small but statistically significant increase with repeating testing: 7 (3-13) at the first measurement, 7 (4-14) at the second measurement and 8 (4-15) at the third measurement (p trend = 0.002). In conclusion, the performance on the RFFT improved by repeating the test over an average follow-up period of three to six years. This practice effect was the largest in young adults and not dependent on educational level.

  12. Synergistic Effects of HIV Infection and Older Age on Daily Functioning

    PubMed Central

    Morgan, Erin E.; Iudicello, Jennifer E.; Weber, Erica; Duarte, Nichole A.; Riggs, P. Katie; Delano-Wood, Lisa; Ellis, Ronald; Grant, Igor; Woods, Steven Paul

    2012-01-01

    Objective To determine whether HIV infection and aging act synergistically to disrupt everyday functioning. Design Cross-sectional, factorial study of everyday functioning in the context of HIV serostatus and age (≤ 40 years vs ≥ 50 years). Methods 103 HIV+ and 87 HIV− participants were administered several measures of everyday functioning, including self-report indices of health-related quality of life (HRQoL) and instrumental and basic activities of daily living (IADLs and BADLs), and objective measures of functioning including employment and Karnofsky Performance Scale (KPS) ratings. Results Significant interaction effects of HIV and aging were observed for IADL and BADL declines, as well as KPS ratings (ps<.05), independent of potentially confounding factors. Follow-up contrasts revealed significantly worse functioning in the older HIV+ group for all functional outcome measures relative to the other study groups (ps<.05). A significant interaction effect was also observed on the emotional functioning HRQoL subscale, and additive effects of both age and HIV were observed for the physical functioning and general health perceptions HRQoL subscales (ps<.05). Significant predictors of poorer functioning in the older HIV+ group included current major depressive disorder for all outcomes, and comorbid medical conditions, lower estimated premorbid functioning, neurocognitive impairment, and nadir CD4 count for selected outcomes. Conclusion Findings suggest that older age may exacerbate the adverse effects of HIV on daily functioning, which highlights the importance of evaluating and monitoring the functional status of older HIV-infected adults. Early detection of functional difficulties could facilitate delivery of compensatory strategies (e.g., cognitive remediation) or assistive services. PMID:22878422

  13. Sensory processing, school performance, and adaptive behavior of young school-age children with fetal alcohol spectrum disorders.

    PubMed

    Jirikowic, Tracy; Olson, Heather Carmichael; Kartin, Deborah

    2008-05-01

    This study described sensory processing behaviors and sensory-motor abilities in children with fetal alcohol spectrum disorders (FASD) and explored their relationship to home and school function. A clinic-referred sample of 25 children with FASD, ages 5 to 8 years, was compared with 26 children with typical development, balanced for age, gender, and race/ethnicity, on standardized tests examining sensory processing, sensory-motor performance, school performance, and adaptive behavior. Children with FASD scored significantly more poorly on sensory processing, sensory-motor, adaptive, and academic achievement measures, and demonstrated more problem behaviors at home and school. Correlations were significant between measures of sensory processing and sensory-motor performance, adaptive behavior, and some aspects of academic performance. Sensory processing and related foundational sensory-motor impairments should be considered when determining the developmental needs of children with FASD. These impairments may co-occur with and contribute, at least in part, to decreased adaptive and school function.

  14. Performance of Older Persons in a Simulated Shopping Task Is Influenced by Priming with Age Stereotypes

    PubMed Central

    Akpinar, Selçuk

    2016-01-01

    Previous research suggests that older persons show cognitive deficits in standardized laboratory tests, but not in more natural tests such as the Multiple Errands Task (MET). The absence of deficits in the latter tests has been attributed to the compensation of deficits by strategies based on life-long experience. To scrutinize this view, we primed older participants with positive or negative stereotypes about old age before administering MET. We found that compared to unprimed controls, priming with positive age stereotypes reduced the number of errors without changing response times, while priming with negative stereotypes changed neither errors not response times. We interpret our findings as evidence that positive age priming improved participants’ cognitive functions while leaving intact their experience-based compensation, and that negative age priming degraded participants’ cognitive functions which, however, was balanced by an even stronger experience-based compensation. PMID:27649296

  15. Influence of Age on Alertness and Performance During 3-Day Cross North-Atlantic Operations

    DTIC Science & Technology

    2000-08-01

    Morrow DG , Yesavage JA , Leirer VO , Tinklenberg J. (1993) The influence of aging and practice on piloting tasks. Exp Aging Res, 19:53-70. 10...Taylor JL, Yesavage JA , Morrow DG , Dolhert N, Brooks, JO, Poon LW. (1994) The effects of information load and speech rate on younger and older...aircraft pilots’ ability to execute simulated air-traffic controller instructions. J Gerontology: Psychological Sciences, 49:191-200. 11. Yesavage JA

  16. Severity of spatial learning impairment in aging: Development of a learning index for performance in the Morris water maze.

    PubMed

    Gallagher, Michela; Burwell, Rebecca; Burchinal, Margaret

    2015-08-01

    The Morris water maze task was originally designed to assess the rat's ability to learn to navigate to a specific location in a relatively large spatial environment. This article describes new measures that provide information about the spatial distribution of the rat's search during both training and probe trial performance. The basic new measure optimizes the use of computer tracking to identify the rat's position with respect to the target location. This proximity measure was found to be highly sensitive to age-related impairment in an assessment of young and aged male Long-Evans rats. Also described is the development of a learning index that provides a continuous, graded measure of the severity of age-related impairment in the task. An index of this type should be useful in correlational analyses with other neurobiological or behavioral measures for the study of individual differences in functional/biological decline in aging.

  17. [A comparative study of the perceptual and motor performance at school age of preterm and full term children].

    PubMed

    Magalhães, Lívia de Castro; Catarina, Patrícia Wendling; Barbosa, Vanêssa Maziero; Mancini, Marisa Cota; Paixão, Maria Lúcia

    2003-06-01

    The objective of this study was to compare the perceptualmotor performance in school age children who were born preterm and full term. Two groups of children, ages 5 to 7, participated in this study. Group I had 35 children, from low-income families, born up to the 34 week of gestation and/or weight bellow 1500 g. Group II had 35 full-term children, matched by age, gender and socioeconomic status to the children in Group I. Children were tested on the Bender gestalt, the motor accuracy test and on balance and postural responses measures. The preterm group obtained significantly lower scores in the majority of the tests. These besides reinforcing the importance of the follow-up of preterm children up to school age, also indicate the need to stimulate the fine motor and postural control Devment, even among preterm children who do not show evidence of neurological impairment.

  18. Acute Physiological and Thermoregulatory Responses to Extended Interval Training in Endurance Runners: Influence of Athletic Performance and Age

    PubMed Central

    García-Pinillos, Felipe; Soto-Hermoso, Víctor Manuel; Latorre-Román, Pedro Ángel

    2015-01-01

    This study aimed to describe the acute impact of extended interval training (EIT) on physiological and thermoregulatory levels, as well as to determine the influence of athletic performance and age effect on the aforementioned response in endurance runners. Thirty-one experienced recreational male endurance runners voluntarily participated in this study. Subjects performed EIT on an outdoor running track, which consisted of 12 runs of 400 m. The rate of perceived exertion, physiological response through the peak and recovery heart rate, blood lactate, and thermoregulatory response through tympanic temperature, were controlled. A repeated measures analysis revealed significant differences throughout EIT in examined variables. Cluster analysis grouped according to the average performance in 400 m runs led to distinguish between athletes with a higher and lower sports level. Cluster analysis was also performed according to age, obtaining an older group and a younger group. The one-way analysis of variance between groups revealed no significant differences (p≥0.05) in the response to EIT. The results provide a detailed description of physiological and thermoregulatory responses to EIT in experienced endurance runners. This allows a better understanding of the impact of a common training stimulus on the physiological level inducing greater accuracy in the training prescription. Moreover, despite the differences in athletic performance or age, the acute physiological and thermoregulatory responses in endurance runners were similar, as long as EIT was performed at similar relative intensity. PMID:26839621

  19. Comparison of Physical Fitness Performance between Elementary-Aged Students with and without Attention Deficit Hyperactivity Disorder

    ERIC Educational Resources Information Center

    Colombo-Dougovito, Andrew M.

    2013-01-01

    The purpose of this investigation was to analyze the possible differences of the physical fitness performance of elementary-aged students with and without attention deficit hyperactivity disorder (ADHD). Little research has been produced in the area of youth with ADHD and motor development; this research paper further investigates the effects of…

  20. The Effects of Visual Stimuli on the Spoken Narrative Performance of School-Age African American Children

    ERIC Educational Resources Information Center

    Mills, Monique T.

    2015-01-01

    Purpose: This study investigated the fictional narrative performance of school-age African American children across 3 elicitation contexts that differed in the type of visual stimulus presented. Method: A total of 54 children in Grades 2 through 5 produced narratives across 3 different visual conditions: no visual, picture sequence, and single…

  1. Evaluating Elementary-Aged Students' Abilities to Generalize and Maintain Fluency Gains of a Performance Feedback Writing Intervention

    ERIC Educational Resources Information Center

    Hier, Bridget O.; Eckert, Tanya L.

    2014-01-01

    National estimates of students' writing abilities in the United States indicate that in 2002, 72% of elementary-aged students were unable to write with grade-level proficiency (Persky, Daane, & Jin, 2003). Although performance feedback is one type of intervention that improves students' writing skills, no study to date has examined…

  2. Age, Sex, and Body Composition as Predictors of Children's Performance on Basic Motor Abilities and Health-Related Fitness Items.

    ERIC Educational Resources Information Center

    Pissanos, Becky W.; And Others

    1983-01-01

    Step-wise linear regressions were used to relate children's age, sex, and body composition to performance on basic motor abilities including balance, speed, agility, power, coordination, and reaction time, and to health-related fitness items including flexibility, muscle strength and endurance and cardiovascular functions. Eighty subjects were in…

  3. Age and gender difference in non-drafting ultra-endurance cycling performance - the ‘Swiss Cycling Marathon’

    PubMed Central

    2013-01-01

    Background In recent years, there was an increased interest in investigating the gender difference in performance and the age of peak performance in ultra-endurance performances such as ultra-triathlon, ultra-running, and ultra-swimming, but not in ultra-cycling. The aim of the present study was to analyze the gender difference in ultra-cycling performance and the age of peak ultra-cycling performance in the 720-km ‘Swiss Cycling Marathon’, the largest European qualifier for the ‘Race Across America’. Methods Changes in the cycling speed and age of 985 finishers including 38 women and 947 men competing in the Swiss Cycling Marathon from 2001 to 2012 covering a distance of 720 km with a change of altitude of 4,993 m were analyzed using linear regression. Results The gender difference in performance was 13.6% for the fastest cyclists ever, 13.9% ± 0.5% for the three fastest cyclists ever and 19.1% ± 3.7% for the ten fastest cyclists ever. The gender difference in performance for the annual top three women and men decreased from 35.0% ± 9.5% in 2001 to 20.4% ± 7.7% in 2012 (r2 = 0.72, p = 0.01). The annual top three women improved cycling speed from 20.3 ± 3.1 km h−1 in 2003 to 24.8 ± 2.4 km h−1 in 2012 (r2 = 0.79, p < 0.01). The cycling speed of the annual top three men remained unchanged at 30.2 ± 0.6 km h−1 (p > 0.05). The age of peak performance for the ten fastest finishers ever was 35.9 ± 9.6 years for men and 38.7 ± 7.8 years for women, respectively (p = 0.47). Conclusions The gender difference in ultra-cycling performance decreased over the 2001 to 2012 period in the 720-km Swiss Cycling Marathon for the annual top three cyclists and reached approximately 14%. Both women and men achieved peak performance at the age of approximately 36 to 39 years. Women might close the gender gap in ultra-endurance cycling in longer cycling distances. Future studies need to investigate the gender difference in performance in the Race Across America, the

  4. The yo-yo intermittent recovery test in junior basketball players according to performance level and age group.

    PubMed

    Vernillo, Gianluca; Silvestri, Adriano; La Torre, Antonio

    2012-09-01

    The aim of this study was to evaluate the Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IR1) ability to discriminate between elite, subelite junior basketball players, and a group of nonathletic healthy male athletes at 3 different age groups (U-14 to U-17). In a cross-sectional design, 119 age-matched participants spread over 3 groups, elite (n = 46), subelite (n = 42) junior basketball players, and nonathletic healthy male athletes (n = 31), were evaluated over a 5-week period. The participants undertook 2 familiarization trials of the Yo-Yo test performance and 3 test sessions on an indoor basketball court. When controlling for the effect of the participants' body mass, the results showed that elite athletes had a significantly higher Yo-Yo performance compared with the subelite athletes (1,271 ± 385 vs. 861 ± 428 m; p < 0.0017; effect size [ES] 1.0 ± 0.35) and the nonathletic group (1,271 ± 385 vs. 738 ± 345 m; p < 0.0017; ES 1.45 ± 0.38). No statistical differences (p > 0.0017; ES from 0.02 to 0.39) were noted between participants' performance levels across age groups. Typical between-performance levels and -age groups differences in the Yo-Yo IR1 were observed. However, when controlling for the effect of the participants' body mass, this study demonstrates that the Yo-Yo test is accurate only to discriminate elite junior basketball players but cannot be used to differentiate the basketball-specific aerobic performance for age.

  5. Yo-Yo Intermittent Recovery Test Performance in Subelite Gaelic Football Players From Under Thirteen to Senior Age Groups.

    PubMed

    Roe, Mark; Malone, Shane

    2016-11-01

    Roe, M and Malone, S. Yo-Yo intermittent recovery test performance in subelite Gaelic football players from under thirteen to senior age groups. J Strength Cond Res 30 (11): 3187-3193, 2016-Gaelic football is indigenous to Ireland and has similar locomotion profiles to soccer and Australian Football. Given the increasing attention on long-term player development, investigations on age-related variation in Yo-Yo intermittent recovery test level 1 (Yo-YoIR1) performance may provide useful information in talent identification, program design, and player monitoring. Therefore, the aim of this study was to evaluate Yo-YoIR1 performance across Gaelic football age groups. Male participants (n = 355) were recruited from division one, Gaelic football teams. Participants were allocated to one of the 7 groups according to respective age groups from under 13 (U13), under 14, under 15 (U15), under 16 (U16), minor, under 21 (U21), to senior age groups. Total Yo-YoIR1 distance (m) increased progressively from U13 (885 ± 347 m) to U16 (1,595 ± 380 m) equating to a rate of change of 180.2%. In comparison to U13, total distance at minor (1,206 ± 327 m) increased by 136.4%. Subsequent increases were observed in U21 (1,585 ± 445 m) and senior players (2,365 ± 489). Minimum (800-880 m) and maximum (2,240-2,280 m) total distances were comparable for U15, U16, and U21 players. Differences in total distance (m) for all age groups were statistically significant when compared to U13 players (p < 0.002). In comparison to U13 players, the magnitude of differences between age groups for total distance was deemed to be large (effect size > 0.8). Similar trends were observed for maximum velocity and estimated V[Combining Dot Above]O2max. The evolution of Yo-YoIR1 performance in Gaelic football players from adolescents to adulthood highlights how maturation may influence sport-related running ability. Changes in Yo-YoIR1 performance should be closely monitored to optimize interventions for

  6. Self-reported chronic pain is associated with physical performance in older people leaving aged care rehabilitation

    PubMed Central

    Pereira, Leani Souza Máximo; Sherrington, Catherine; Ferreira, Manuela L; Tiedemann, Anne; Ferreira, Paulo H; Blyth, Fiona M; Close, Jacqueline CT; Taylor, Morag; Lord, Stephen R

    2014-01-01

    Background/objectives The impact of pain on the physical performance of patients in aged care rehabilitation is not known. The study sought to assess 1) the prevalence of pain in older people being discharged from inpatient rehabilitation; 2) the association between self-reported pain and physical performance in people being discharged from inpatient rehabilitation; and 3) the association between self-reported pain and physical performance in this population, after adjusting for potential confounding factors. Methods This was an observational cross-sectional study of 420 older people at two inpatient aged care rehabilitation units. Physical performance was assessed using the Lower Limb Summary Performance Score. Pain was assessed with questions about the extent to which participants were troubled by pain, the duration of symptoms, and the impact of chronic pain on everyday activity. Depression and the number of comorbidities were assessed by questionnaire and medical file audit. Cognition was assessed with the Mini-Mental State Examination. Results Thirty percent of participants reported chronic pain (pain lasting more than 3 months), and 17% reported that this pain interfered with daily activities to a moderate or greater extent. Chronic pain (P=0.013) and chronic pain affecting daily activities (P<0.001) were associated with a poorer Lower Limb Summary Performance Score. The relationship between chronic pain affecting daily activities and Lower Limb Summary Performance Score remained significant (P=0.001) after adjusting for depression, age, comorbidities, and Mini-Mental State Examination score. This model explained 10% of the variability in physical performance. Conclusion One-third of participants reported chronic pain, and close to one-fifth reported that this pain interfered with daily activities. Chronic pain was associated with impaired physical performance, and this relationship persisted after adjusting for likely confounding factors. PMID:24523583

  7. Age differences in cognitive performance in later life: relationships to self-reported health and activity life style.

    PubMed

    Hultsch, D F; Hammer, M; Small, B J

    1993-01-01

    The predictive relationships among individual differences in self-reported physical health and activity life style and performance on an array of information processing and intellectual ability measures were examined. A sample of 484 men and women aged 55 to 86 years completed a battery of cognitive tasks measuring verbal processing time, working memory, vocabulary, verbal fluency, world knowledge, word recall, and text recall. Hierarchical regression was used to predict performance on these tasks from measures of self-reported physical health, alcohol and tobacco use, and level of participation in everyday activities. The results indicated: (a) individual differences in self-reported health and activity predicted performance on multiple cognitive measures; (b) self-reported health was more predictive of processing resource variables than knowledge-based abilities; (c) interaction effects indicated that participation in cognitively demanding activities was more highly related to performance on some measures for older adults than for middle-aged adults; and (d) age-related differences in performance on multiple measures were attenuated by partialing individual differences in self-reported health and activity.

  8. A healthy Nordic diet and physical performance in old age: findings from the longitudinal Helsinki Birth Cohort Study.

    PubMed

    Perälä, Mia-Maria; von Bonsdorff, Mikaela; Männistö, Satu; Salonen, Minna K; Simonen, Mika; Kanerva, Noora; Pohjolainen, Pertti; Kajantie, Eero; Rantanen, Taina; Eriksson, Johan G

    2016-03-14

    Epidemiological studies have shown that a number of nutrients are associated with better physical performance. However, little is still known about the role of the whole diet, particularly a healthy Nordic diet, in relation to physical performance. Therefore, we examined whether a healthy Nordic diet was associated with measures of physical performance 10 years later. We studied 1072 participants from the Helsinki Birth Cohort Study. Participants' diet was assessed using a validated 128-item FFQ at the mean age of 61 years, and a priori-defined Nordic diet score (NDS) was calculated. The score included Nordic fruits and berries, vegetables, cereals, PUFA:SFA and trans-fatty acids ratio, low-fat milk, fish, red and processed meat, total fat and alcohol. At the mean age of 71 years, participants' physical performance was measured using the Senior Fitness Test (SFT), and an overall SFT score was calculated. Women in the highest fourth of the NDS had on average 5 points higher SFT score compared with those in the lowest fourth (P for trend 0·005). No such association was observed in men. Women with the highest score had 17% better result in the 6-min walk test, 16% better arm curl and 20% better chair stand results compared with those with the lowest score (all P values<0·01). In conclusion, a healthy Nordic diet was associated with better overall physical performance among women and might help decrease the risk of disability in old age.

  9. The STEP model: Characterizing simultaneous time effects on practice for flight simulator performance among middle-aged and older pilots.

    PubMed

    Kennedy, Quinn; Taylor, Joy; Noda, Art; Yesavage, Jerome; Lazzeroni, Laura C

    2015-09-01

    Understanding the possible effects of the number of practice sessions (practice) and time between practice sessions (interval) among middle-aged and older adults in real-world tasks has important implications for skill maintenance. Prior training and cognitive ability may impact practice and interval effects on real-world tasks. In this study, we took advantage of existing practice data from 5 simulated flights among 263 middle-aged and older pilots with varying levels of flight expertise (defined by U.S. Federal Aviation Administration proficiency ratings). We developed a new Simultaneous Time Effects on Practice (STEP) model: (a) to model the simultaneous effects of practice and interval on performance of the 5 flights, and (b) to examine the effects of selected covariates (i.e., age, flight expertise, and 3 composite measures of cognitive ability). The STEP model demonstrated consistent positive practice effects, negative interval effects, and predicted covariate effects. Age negatively moderated the beneficial effects of practice. Additionally, cognitive processing speed and intraindividual variability (IIV) in processing speed moderated the benefits of practice and/or the negative influence of interval for particular flight performance measures. Expertise did not interact with practice or interval. Results indicated that practice and interval effects occur in simulated flight tasks. However, processing speed and IIV may influence these effects, even among high-functioning adults. Results have implications for the design and assessment of training interventions targeted at middle-aged and older adults for complex real-world tasks.

  10. The STEP model: Characterizing simultaneous time effects on practice for flight simulator performance among middle-aged and older pilots

    PubMed Central

    Kennedy, Quinn; Taylor, Joy; Noda, Art; Yesavage, Jerome; Lazzeroni, Laura C.

    2015-01-01

    Understanding the possible effects of the number of practice sessions (practice) and time between practice sessions (interval) among middle-aged and older adults in real world tasks has important implications for skill maintenance. Prior training and cognitive ability may impact practice and interval effects on real world tasks. In this study, we took advantage of existing practice data from five simulated flights among 263 middle-aged and older pilots with varying levels of flight expertise (defined by FAA proficiency ratings). We developed a new STEP (Simultaneous Time Effects on Practice) model to: (1) model the simultaneous effects of practice and interval on performance of the five flights, and (2) examine the effects of selected covariates (age, flight expertise, and three composite measures of cognitive ability). The STEP model demonstrated consistent positive practice effects, negative interval effects, and predicted covariate effects. Age negatively moderated the beneficial effects of practice. Additionally, cognitive processing speed and intra-individual variability (IIV) in processing speed moderated the benefits of practice and/or the negative influence of interval for particular flight performance measures. Expertise did not interact with either practice or interval. Results indicate that practice and interval effects occur in simulated flight tasks. However, processing speed and IIV may influence these effects, even among high functioning adults. Results have implications for the design and assessment of training interventions targeted at middle-aged and older adults for complex real world tasks. PMID:26280383

  11. Effects of the nicotinic agonist varenicline on the performance of tasks of cognition in aged and middle-aged rhesus and pigtail monkeys

    PubMed Central

    Terry, Alvin V.; Plagenhoef, Marc; Callahan, Patrick M.

    2015-01-01

    Rationale Due to the rising costs of drug development especially in the field of neuropsychiatry there is increasing interest in efforts to identify new clinical uses for existing approved drugs (i.e., drug repurposing). Objectives The purpose of this work was to evaluate in animals the smoking cessation agent, varenicline, a partial agonist at α4β2 and full agonist at α7 nicotinic acetylcholine receptors, for its potential as a repurposed drug for disorders of cognition. Methods Oral doses of varenicline ranging from 0.01 to 0.3 mg/kg were evaluated in aged and middle aged monkeys for effects on: working/short term memory in a delayed match to sample (DMTS) task, distractibility in a distractor version of the DMTS (DMTS-D), and cognitive flexibility in a ketamine-impaired reversal learning task. Results In dose-effect studies in the DMTS and DMTS-D tasks, varenicline was not associated with statistically significant effects on performance. However, individualized “optimal doses” were effective when repeated on a separate occasion (i.e., improving DMTS accuracy at long delays and DMTS-D accuracy at short delays by approximately 13.6 and 19.6 percentage points above baseline, respectively). In reversal learning studies, ketamine impaired accuracy and increased perseverative responding, effects that were attenuated by all three doses of varenicline that were evaluated. Conclusions While the effects of varenicline across the different behavioral tasks were modest, these data suggest that varenicline may have potential as a repurposed drug for disorders of cognition associated with aging (e.g., Alzheimer’s disease), as well as those not necessarily associated with advanced age (e.g., schizophrenia). PMID:26612616

  12. Age-related individual variability in memory performance is associated with amygdala-hippocampal circuit function and emotional pattern separation.

    PubMed

    Leal, Stephanie L; Noche, Jessica A; Murray, Elizabeth A; Yassa, Michael A

    2017-01-01

    While aging is generally associated with episodic memory decline, not all older adults exhibit memory loss. Furthermore, emotional memories are not subject to the same extent of forgetting and appear preserved in aging. We conducted high-resolution fMRI during a task involving pattern separation of emotional information in older adults with and without age-related memory impairment (characterized by performance on a word-list learning task: low performers: LP vs. high performers: HP). We found signals consistent with emotional pattern separation in hippocampal dentate (DG)/CA3 in HP but not in LP individuals, suggesting a deficit in emotional pattern separation. During false recognition, we found increased DG/CA3 activity in LP individuals, suggesting that hyperactivity may be associated with overgeneralization. We additionally observed a selective deficit in basolateral amygdala-lateral entorhinal cortex-DG/CA3 functional connectivity in LP individuals during pattern separation of negative information. During negative false recognition, LP individuals showed increased medial temporal lobe functional connectivity, consistent with overgeneralization. Overall, these results suggest a novel mechanistic account of individual differences in emotional memory alterations exhibited in aging.

  13. Performance of repair welds on service-aged 2-1/4Cr-1Mo girth weldments

    SciTech Connect

    Viswanathan, R.; Gandy, D.; Findlan, S.

    1997-11-01

    This paper discusses the results of evaluations performed on service-aged piping using both conventional postweld heat treatments and temperbead repair techniques. The two repair weldments were accomplished on two 2-1/4Cr-1Mo pipe girth weldments which were removed from a utility hot reheat piping system in the fall of 1992 after 161,000 h of operation at 1,000 F (538 C). Each repair was performed around one-half of the diameter of a pipe girth weldment, while the remaining half of the girth weldment was left in the service-aged condition. Post-repair metallurgical and mechanical test results indicated that both weld repairs produced improved remaining lives when compared to the service-aged girth weldments. Since the two ex-service weldments that were utilized in weld repairs exhibited different stress rupture strengths to start with, the performance of temper bead and postweld heat-treated (PWHT) repair could not be compared directly. It was clear, however, that life extension periods exceeding 30 yr could be achieved by temperbead repairs, with improved toughness and with no loss of stress rupture ductility, tensile strength, or yield strength. The temperbead repair improved the toughness of the service-aged weldment, while the postweld heat-treated repair lowered the HAZ toughness.

  14. Differences in age of peak marathon performance between mountain and city marathon running - The ‘Jungfrau Marathon’ in Switzerland.

    PubMed

    Knechtle, Beat; Nikolaidis, Pantelis Theodoros; Zingg, Matthias Alexander; Rosemann, Thomas; Rüst, Christoph Alexander

    2017-02-28

    The age of the best marathon performance has been well investigated for flat city marathon running, but not for mountain marathon running. The aim of this study was to determine the age of the best mountain marathon performance and to compare to results of a flat city marathon. Race times and ages of finishers of a mountain marathon with 1,830 m of altitude change (Jungfrau Marathon, Switzerland) and two flat city marathons (Lausanne Marathon and Zurich Marathon, Switzerland) were analysed using linear, non-linear and mixed-effects regression analyses. Race times were slower in the mountain compared to the city marathon. In both the mountain marathon and the city marathons, women and men improved performance and men were faster than women when the fastest per year and all per year were considered. When the fastest runners in 1-year age intervals were considered in the mountain marathon, the fastest man (3:01 h:min) was ~35.6 years and the fastest women (3:28 h:min) ~34.5 years old. When all finishers were considered in 1-year age intervals, the fastest men (4:59 h:min) were ~29.1 years old and the fastest women (5:16 h:min) were ~25.6 years old. In the city marathons in 1-year age intervals, the fastest man (2:10 h:min) was ~23.7 years old and the fastest woman (2:36 h:min) ~32.2 years old. When all finishers were considered in 1-year age intervals, the fastest men (3:41 h:min) were ~35.0 years old and the fastest women (4:00 h:min) ~33.8 years old. In summary, the age of the fastest women and men was higher in the mountain marathon compared to the city marathons when the fastest runners were considered. However, when all finishers were considered the age of the fastest women and men was lower in the mountain marathon compared to the city marathons.

  15. Effect of postmortem aging on marination performance of broiler breast pectoralis major categorized by color lightness

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective was to evaluate the effect of postmortem aging on marinade uptake and retention by early-deboned chicken breast fillets with different color lightness. Effects of marination on product yield and muscle shear force were also determined. Early deboned (2 h postmortem) broiler butterflies...

  16. Discrimination Performance in Aging Is Vulnerable to Interference and Dissociable from Spatial Memory

    ERIC Educational Resources Information Center

    Johnson, Sarah A.; Sacks, Patricia K.; Turner, Sean M.; Gaynor, Leslie S.; Ormerod, Brandi K.; Maurer, Andrew P.; Bizon, Jennifer L.; Burke, Sara N.

    2016-01-01

    Hippocampal-dependent episodic memory and stimulus discrimination abilities are both compromised in the elderly. The reduced capacity to discriminate between similar stimuli likely contributes to multiple aspects of age-related cognitive impairment; however, the association of these behaviors within individuals has never been examined in an animal…

  17. Individual Differences in Spatial Pattern Separation Performance Associated with Healthy Aging in Humans

    ERIC Educational Resources Information Center

    Stark, Shauna M.; Yassa, Michael A.; Stark, Craig E. L.

    2010-01-01

    Rodent studies have suggested that "pattern separation," the ability to distinguish among similar experiences, is diminished in a subset of aged rats. We extended these findings to the human using a task designed to assess spatial pattern separation behavior (determining at time of test whether pairs of pictures shown during the study were in the…

  18. Influence of amyloid and APOE on cognitive performance in a late middle-aged cohort

    PubMed Central

    Mielke, Michelle M.; Machulda, Mary M.; Hagen, Clinton E.; Christianson, Teresa J.; Roberts, Rosebud O.; Knopman, David S.; Vemuri, Prashanthi; Lowe, Val J.; Kremers, Walter K.; Jack, Clifford R.; Petersen, Ronald C.

    2015-01-01

    INTRODUCTION Few studies have examined the effects of amyloid and APOE genotype on cognition among middle-aged individuals. METHODS We included 464 cognitively normal, test-naïve, participants with PiB-PET amyloid imaging, mean age of 62.7 (range 51–71 years), enrolled in the Mayo Clinic Study of Aging. Participants completed multiple cognitive assessments, including a standard neuropsychological battery and the CogState computerized battery, over 30 months of follow-up. Linear mixed models were used to examine the effects of amyloid and APOE genotype on baseline cognition and cognitive decline. RESULTS Elevated amyloid was not associated with tests of episodic memory, but did predict declines on tests of executive function. APOE genotype was not associated with cognition. Among APOE ε4 non-carriers, higher amyloid was predictive of decline on tests of executive function and on one episodic memory test. DISCUSSION Elevated amyloidosis and APOE genotype does not appear to exert a dramatic influence on cognition in middle-age. PMID:26602629

  19. Handwriting performance in preterm children compared with term peers at age 6 to 7 years.

    PubMed

    Feder, Katya P; Majnemer, Annette; Bourbonnais, Daniel; Platt, Robert; Blayney, Marc; Synnes, Anne

    2005-03-01

    Preterm infants are at high risk for developmental impairments at school age. However, the impact of these impairments on important life skills, such as handwriting, is unknown. Forty-eight first-grade children (27 males, 21 females; mean age 6y 7mo, SD 3.9mo; range 6y 1mo to 7y 3mo) born preterm (birthweight < 1250g; gestational age < 34wks), without major physical or cognitive disabilities, were matched to 69 healthy, term control children (32 males, 37 females; mean age 6y 10mo, SD 3.6mo; range 6y 3mo to 7y 4mo) by sex and school class. All children were assessed using the Evaluation Tool of Children's Handwriting-Manuscript and several sensorimotor measures. Preterm children demonstrated significantly lower legibility and slower speed scores (p < 0.01) compared with control children for most of the handwriting tasks. Factors associated with legibility were visual perception and eye-hand coordination (r < 0.50; p < 0.05) and sex (r < 0.12; p = 0.01). In-hand manipulation and finger identification (r < 0.43; p < 0.01) were significantly correlated with slow handwriting speeds. Behaviour difficulties associated with hyperactivity and poor attention (Connors Abbreviated Symptoms Questionnaire) had a confounding influence on both legibility and speed. These findings may help guide early identification efforts and medical/therapeutic interventions for preterm children.

  20. A Twin Study of Spatial and Non-Spatial Delayed Response Performance in Middle Age

    ERIC Educational Resources Information Center

    Kremen, William S.; Mai, Tuan; Panizzon, Matthew S.; Franz, Carol E.; Blankfeld, Howard M.; Xian, Hong; Eisen, Seth A.; Tsuang, Ming T.; Lyons, Michael J.

    2011-01-01

    Delayed alternation and object alternation are classic spatial and non-spatial delayed response tasks. We tested 632 middle-aged male veteran twins on variants of these tasks in order to compare test difficulty, measure their inter-correlation, test order effects, and estimate heritabilities (proportion of observed variance due to genetic…

  1. Age and Function Differences in Shared Task Performance: Walking and Talking

    ERIC Educational Resources Information Center

    Williams, Kathleen; Hinton, Virginia A.; Bories, Tamara; Kovacs, Christopher R.

    2006-01-01

    Less is known about the effects of normal aging on speech output than other motor actions, because studies of communication integrity have focused on voice production and linguistic parameters rather than speech production characteristics. Studies investigating speech production in older adults have reported increased syllable duration (Slawinski,…

  2. Effects of aging on cerebral oxygenation during working-memory performance: a functional near-infrared spectroscopy study.

    PubMed

    Vermeij, Anouk; van Beek, Arenda H E A; Olde Rikkert, Marcel G M; Claassen, Jurgen A H R; Kessels, Roy P C

    2012-01-01

    Working memory is sensitive to aging-related decline. Evidence exists that aging is accompanied by a reorganization of the working-memory circuitry, but the underlying neurocognitive mechanisms are unclear. In this study, we examined aging-related changes in prefrontal activation during working-memory performance using functional Near-Infrared Spectroscopy (fNIRS), a noninvasive neuroimaging technique. Seventeen healthy young (21-32 years) and 17 healthy older adults (64-81 years) performed a verbal working-memory task (n-back). Oxygenated and deoxygenated hemoglobin concentration changes were registered by two fNIRS channels located over the left and right prefrontal cortex. Increased working-memory load resulted in worse performance compared to the control condition in older adults, but not in young participants. In both young and older adults, prefrontal activation increased with rising working-memory load. Young adults showed slight right-hemispheric dominance at low levels of working-memory load, while no hemispheric differences were apparent in older adults. Analysis of the time-activation curve during the high working-memory load condition revealed a continuous increase of the hemodynamic response in the young. In contrast to that, a quadratic pattern of activation was found in the older participants. Based on these results it could be hypothesized that young adults were better able to keep the prefrontal cortex recruited over a prolonged period of time. To conclude, already at low levels of working-memory load do older adults recruit both hemispheres, possibly in an attempt to compensate for the observed aging-related decline in performance. Also, our study shows that aging effects on the time course of the hemodynamic response must be taken into account in the interpretation of the results of neuroimaging studies that rely on blood oxygen levels, such as fMRI.

  3. Effect of feeding program during rearing and age at first insemination on performances during subsequent reproduction in young rabbit does.

    PubMed

    Rommers, Jorine M; Meijerhof, Ron; Noordhuizen, Jos P T M; Kemp, Bas

    2004-01-01

    An experiment was performed to study the effect of the feeding program and age at first mating on body growth, feed intake, reproductive performance, and culling of rabbit does over three parities, using 155 does of a strain of New Zealand white rabbits. Three treatments were applied. Ad libitum feeding until first insemination at 14.5 wk (AL-14.5) or 17.5 wk of age (AL-17.5), and restrictive feeding from five wk of age until first insemination at 17.5 wk of age (R-17.5). At first insemination, the BW of AL-14.5 and R-17.5 was similar (3 907 vs. 3 791 +/- 46 g, respectively), whereas AL-17.5 does were heavier (4 390 +/- 46 g, P < 0.001). During reproduction, performance of AL-17.5 was not improved compared to AL-14.5 and R-17.5 does. Al-17.5 does showed a lower feed intake during the first gestation (-25%) and first parity (-10%) than R- 17.5, resulting in weight loss (-6%) during the first gestation and decreased litter weights (-19%) and litter growth (-14%) in the first parity. Extended first mating by three wk (17.5 vs. 14.5 wk) but similar BW at first mating did not affect feed intake and BW development during the first three parities. However, the number of live born kits and weight at first kindling, and litter growth in the first parity were improved in R-17.5 (+23%, +18%, and +14%, respectively). Reproductive performance can be improved by restricted feeding during rearing and extended first insemination to 17.5 wk of age. However, the culling rate was not affected by the rearing strategy.

  4. Influence of physical fitness, age, experience, and weekly training load on match performance in elite Australian football.

    PubMed

    Gastin, Paul B; Fahrner, Brendan; Meyer, Denny; Robinson, Dean; Cook, Jill L

    2013-05-01

    Season long competition schedules in football create unique challenges for coaches in balancing the requirements of recovery, developing and maintaining physical fitness, and adjusting the training load before each match. The aim of this study was to investigate the influence of player characteristics (physical fitness, age, and playing experience) and weekly in-season training load on elite match performance across an Australian football season. Twenty-five players (age: 24.1 ± 3.0 years; height: 188.3 ± 7.3 cm; weight: 90.4 ± 8.3 kg) from one elite team participated in this study. Before the season, player's age, experience, height, and weight along with measures of aerobic (6-minute run) and anaerobic (6 × 40 m repeated sprints) physical fitness were recorded. Individual player training load during the season was measured using global positioning system technology for the main training session of the week. Player match performance was calculated weekly from 33 individual playing statistics. Multilevel modeling was used to investigate the relationship between weekly training load and match performance and to explore the influence of player characteristics on this relationship. Playing experience (p < 0.01) and aerobic fitness (p < 0.05) displayed positive relationships with performance, whereas player age (p < 0.01) showed a negative relationship. Most players coped well with weekly variations in training load; however, the relationship was moderated by the results of the preseason repeated sprint test (p < 0.05). The adverse effect on playing performance in selected players after a more intense training session suggests that recovery from the session may be delayed in players who exhibit a better anaerobic fitness profile.

  5. Allogeneic Stem Cell Transplantation for Patients Age ≥ 70 Years with Myelodysplastic Syndrome: A Retrospective Study of the MDS Subcommittee of the Chronic Malignancies Working Party of the EBMT.

    PubMed

    Heidenreich, Silke; Ziagkos, Dimitris; de Wreede, Liesbeth C; van Biezen, Anja; Finke, Jürgen; Platzbecker, Uwe; Niederwieser, Dietger; Einsele, Hermann; Bethge, Wolfgang; Schleuning, Michael; Beelen, Dietrich W; Tischer, Johanna; Nagler, Arnon; Glass, Bertram; Maertens, Johan; Yáñez, Lucrecia; Beguin, Yves; Sill, Heinz; Scheid, Christof; Stelljes, Matthias; Ganser, Arnold; Zachée, Pierre; Selleslag, Dominik; de Witte, Theo; Robin, Marie; Kröger, Nicolaus

    2017-01-01

    In this retrospective analysis we evaluated the outcome of 313 patients aged ≥ 70 years in the registry of the European Group for Blood and Marrow Transplantation with myelodysplastic syndrome (MDS; n = 221) and secondary acute myeloid leukemia (n = 92) who underwent allogeneic hematopoietic stem cell transplantation (HSCT) from related (n = 79) or unrelated (n = 234) donors. Median age at HSCT was 72 years (range, 70 to 78). Conditioning regimen was nonmyeloablative (n = 54), reduced intensity (n = 207), or standard intensity (n = 52). Allogeneic HSCT for MDS patients ≥ 70 years was increasingly performed over time. Although during 2000 to 2004 only 16 patients received HSCT, during 2011 to 2013 the number of transplantations increased to 181. The cumulative incidence of nonrelapse mortality at 1 year and relapse at 3 years was 32% and 28%, respectively, with a 3-year overall survival rate of 34%. Good performance, determined by Karnofsky performance status, and recipients' seronegativity for cytomegalovirus was associated with 3-year estimated overall survival rates of 43% (P = .01) and 46% (P = .002), respectively. Conditioning intensity did not impact survival. After careful patient selection, allogeneic HSCT can be offered to patients older than 70 years with MDS.

  6. Job Performance of Transition-Age Youth with Emotional and Behavioral Disorders.

    ERIC Educational Resources Information Center

    Carter, Erik W.; Wehby, Joseph H.

    2003-01-01

    A study examined the job performance of 47 adolescents with emotional and behavioral disorders. Significant discrepancies were found between supervisors' ratings of the importance of work behaviors and their ratings of adolescents' performance of the same behaviors. Adolescents' self-evaluations were significantly more favorable than the ratings…

  7. Changes in Motor Strategies across Age Performing a Longswing on the High Bar

    ERIC Educational Resources Information Center

    Busquets, Albert; Marina, Michel; Angulo-Barroso, Rosa

    2013-01-01

    Purpose: Improvements in motor performance and coordination may be impacted by the interaction of practice and organismic constraints. It has been proposed that these aspects of motor learning are achieved at a different time rate: first, during placement of the events (performance), and second, segmental spatiotemporal relationships…

  8. Aging and Intraindividual Variability in Performance: Analyses of Response Time Distributions

    ERIC Educational Resources Information Center

    Myerson, Joel; Robertson, Shannon; Hale, Sandra

    2007-01-01

    It has been suggested that older adults are more variable in their performance because they are more prone to lapses of either attention or intention. In the present experiment, 9 young and 9 older adults each performed nearly 2,000 trials of a same-different judgment task. As expected, older adults were slower and more variable than young adults.…

  9. Effects of Music Loudness on Task Performance and Self-Report of College-Aged Students.

    ERIC Educational Resources Information Center

    Wolfe, David E.

    1983-01-01

    The effects of the loudness of background music on task performance of college students was studied. Results indicated that the experimental conditions had no significant effect on task performance; the majority of students did recognize the music; and students in the 80-90 B group perceived the music as most distracting. (Author/IS)

  10. Performance and Age of the Fastest Female and Male 100-KM Ultramarathoners Worldwide From 1960 to 2012.

    PubMed

    Cejka, Nadine; Knechtle, Beat; Rüst, Christoph A; Rosemann, Thomas; Lepers, Romuald

    2015-05-01

    The purpose of this cross-sectional study was to investigate the change in 100-km running performance and in the age of peak performance for 100-km ultramarathoners. Age and running speed of the annual fastest women and men in all 100-km ultramarathons held worldwide between 1960 and 2012 were analyzed in 148,017 finishes with 18,998 women and 129,019 men using single, multivariate, and nonlinear regressions. Running speed of the annual fastest men increased from 8.67 to 15.65 km.h(-1) and from 8.06 to 13.22 km.h(-1) for the annual fastest women. For the annual 10 fastest men, running speed increased from 10.23 ± 1.22 to 15.05 ± 0.29 km.h(-1) (p < 0.0001) and for the annual 10 fastest women from 7.18 ± 1.54 to 13.03 ± 0.18 km.h(-1) (p < 0.0001). The sex difference decreased from 56.1 to 16.3% for the annual fastest finishers (p < 0.0001) and from 46.7 ± 8.7% to 14.0 ± 1.2% for the annual 10 fastest finishers (p < 0.0001). The age of the annual fastest men increased from 29 to 40 years (p = 0.025). For the annual fastest women, the age remained unchanged at 35.0 ± 9.7 years (p = 0.469). For the annual 10 fastest women and men, the age remained unchanged at 34.9 ± 3.2 (p = 0.902) and 34.5 ± 2.5 years (p = 0.064), respectively. To summarize, 100-km ultramarathoners became faster, the sex difference in performance decreased but the age of the fastest finishers remained unchanged at ∼ 35 years. For athletes and coaches to plan a career as 100-km ultramarathoner, the age of the fastest female and male 100-km ultramarathoners remained unchanged at ∼ 35 years between 1960 and 2012 although the runners improved their performance over time.

  11. Performance of an age series of alnus-cardamom plantations in the Sikkim Himalaya: productivity, energetics and efficiencies.

    PubMed

    Sharma, G; Sharma, E; Sharma, R; Singh, K K

    2002-03-01

    Biomass, net primary productivity, energetics and energy efficiencies were estimated in an age series of Alnus-cardamom plantations in the eastern Himalaya. The impact of stand age (5, 10, 15, 20, 30 and 40 years) on the performance of mixtures of N2-fixing (Alnus nepalensis) and non-N2-fixing (large cardamom) plants was studied. Large cardamom (Amomum subulatum) is the most important perennial cash crop in the region and is cultivated predominantly under Alnus trees. Net primary productivity was lowest (7 t ha(-1) per year) in the 40-year-old stand and was more than three times higher (22 t ha(-1) per year) in the 15-year-old stand. Agronomic yield of large cardamom peaked between 15 and 20 years of age. Cardamom productivity doubled from the 5- to the 15-year-old stand, and then decreased with plantation age to reach a minimum in the 40-year-old stand. Performance of cardamom in association of N2-fixing Alnus remained beneficial until 20 years of age. Annual net energy fixation was highest (444 x 10(6) kJ ha(-1) per year) in the 15-year-old stand, being 1.4 times that of the 5-year-old stand and 2.9-times that of the 40-year-old stand. Inverse relationships of production efficiency, energy conversion efficiency and energy utilized in N2-fixation against stand age, and a positive relationship between production efficiency and energy conversion efficiency suggest that the younger plantations are more productive. The Alnus-cardamom plantation system will be sustainable by adopting a rotational cycle of 15 to 20 years.

  12. Performance and age of African and non-African runners in World Marathon Majors races 2000-2014.

    PubMed

    Knechtle, Beat; Aschmann, André; Onywera, Vincent; Nikolaidis, Pantelis T; Rosemann, Thomas; Rüst, Christoph Alexander

    2017-05-01

    The age for the fastest marathoners is well investigated, but not the age and nationality of the fastest. We investigated the age of peak marathon performance for the annual top 100 women and men competing in four races of the "World Marathon Majors" (Boston, Berlin, Chicago and New York) and the "Stockholm Marathon" between 2000 and 2014 using mixed-effects regression analyses and one-way ANOVA. Race times of Ethiopian men decreased to 2:14 h:min, but remained unchanged for Kenyan (2:14 h:min), Moroccan (2:15 h:min) and South African (2:18 h:min) men. Race times in Ethiopian (2:34 h:min), Kenyan (2:29 h:min) and South African (2:49 h:min) women showed no changes. Age increased in Ethiopian and South African men to 29.0 ± 5.0 and 32.0 ± 1.0 years, respectively. Age for Kenyan (29.9 ± 2.0 years) and Moroccan (34.9 ± 3.9 years) men remained unchanged. Age remained unchanged for Ethiopian (26.5 ± 2.0 years), Kenyan (30.0 ± 0.8 years) and South African (36.3 ± 7.0 years) women. In summary, Ethiopian men improved marathon race times, but not Ethiopian women. Age increased in Ethiopian men, but not in Ethiopian women. For practical applications, female and male marathoners from Ethiopia were the youngest and the fastest.

  13. Aging and analytical performances evolution of a gas chromatographic system at Mars

    NASA Astrophysics Data System (ADS)

    Bonnet, J.-Y.; Szopa, C.; Millan, M.; Coscia, D.; Cabane, M.; Belmahdi, I.; Buch, A.; Dequaire, T.; Coll, P.; Teinturier, S.; Mahaffy, P.

    2015-10-01

    Health data from the gas chromatography (GC) module onboard the SAM instrument [1] will be presented to assess the analytical performances evolution of a GC device in Martian environment through 3 years.

  14. Performance studies under high irradiation and ageing properties of resistive bulk Micromegas chambers at the new CERN Gamma Irradiation Facility

    NASA Astrophysics Data System (ADS)

    Sidiropoulou, O.; Gonzalez, B. Alvarez; Bianco, M.; Farina, E. M.; Iengo, P.; Longo, L.; Pfeiffer, D.; Wotschack, J.

    2017-02-01

    Resistive bulk Micromegas chambers, produced at CERN, have been installed at the new CERN Gamma Irradiation Facility (GIF++) in order to study the effects of ageing and to evaluate the detector behaviour under high irradiation. The chambers have an active area of 10×10 cm2, strip pitch of 400 μm and an amplification gap of 128 μm. We present the detector performance as a function of the background rate of up to 20 MHz/cm2.

  15. Physical Activity, Sleep, and Nutrition Do Not Predict Cognitive Performance in Young and Middle-Aged Adults

    PubMed Central

    Gijselaers, Hieronymus J. M.; Elena, Barberà; Kirschner, Paul A.; de Groot, Renate H. M.

    2016-01-01

    Biological lifestyle factors (BLFs) such as physical activity, sleep, and nutrition play a role in cognitive functioning. Research concerning the relation between BLFs and cognitive performance is scarce however, especially in young and middle-aged adults. Research has not yet focused on a multidisciplinary approach with respect to this relation in the abovementioned population, where lifestyle habits are more stable. The aim of this study was to examine the contribution of these BLFs to cognitive performance. Path analysis was conducted in an observational study in which 1131 adults were analyzed using a cross-validation approach. Participants provided information on physical activity, sedentary behavior, chronotype, sleep duration, sleep quality, and the consumption of breakfast, fish, and caffeine via a survey. Their cognitive performance was measured using objective digital cognitive tests. Exploration yielded a predictive cohesive model that fitted the data properly, χ2/df = 0.8, CFI = 1.00, RMSEA < 0.001, SRMR = 0.016. Validation of the developed model indicated that the model fitted the data satisfactorily, χ2/df = 2.75, CFI = 0.95, RMSEA < 0.056, SRMR = 0.035. None of the variables within the BLFs were predictive for any of the cognitive performance measures, except for sedentary behavior. Although sedentary behavior was positively predictive for processing speed its contribution was small and unclear. The results indicate that the variables within the BLFs do not predict cognitive performance in young and middle-aged adults. PMID:27199867

  16. Variability and reduced performance of preschool- and early school-aged children on psychoacoustic tasks: What are the relevant factors?

    NASA Astrophysics Data System (ADS)

    Allen, Prudence

    2003-04-01

    Young children typically perform more poorly on psychoacoustic tasks than do adults, with large individual differences. When performance is averaged across children within age groups, the data suggest a gradual change in performance with increasing age. However, an examination of individual data suggests that the performance matures more rapidly, although at different times for different children. The mechanisms of development responsible for these changes are likely very complex, involving both sensory and cognitive processes. This paper will discuss some previously suggested mechanisms including attention and cue weighting, as well as possibilities suggested from more recent studies in which learning effects were examined. In one task, a simple frequency discrimination was required, while in another the listener was required to extract regularities in complex sequences of sounds that varied from trial to trial. Results suggested that the ability to select and consistently employ an effective listening strategy was especially important in the performance of the more complex task, while simple stimulus exposure and motivation contributed to the simpler task. These factors are important for understanding the perceptual development and for the subsequent application of psychoacoustic findings to clinical populations. [Work supported by the NSERC and the Canadian Language and Literacy Research Network.

  17. Color temperature’s impact on task performance and brainwaves of school-age children

    PubMed Central

    Park, YunHee

    2015-01-01

    [Purpose] This study investigated color temperature’s impact on task performance. It presents a scientific analysis of brainwave and task performance time changes, and the results of a self-report type survey. [Subjects] Twenty-four elementary school fifth-grade boys and girls with no visual problems participated in the experiment. [Methods] Physiological reaction times of task performance were measured in a laboratory that could fix and maintain color temperature. Brainwave changes and the task performance times were measured, and a self-report questionnaire was conducted in order to measure of emotional reactions. [Results] Regarding the brainwave changes associated with color temperature, alpha waves were emitted in the O2 area when puzzle tasks were illuminated by orange light and low and high beta waves were emitted in the F3 area under white light. Five items (Brilliant, Soft, Lively, Relaxed, Open) were reported predominantly in responses to orange light in the self-report questionnaire. [Conclusion] The results of this study show that relaxation and stability are not assured when the color temperature is low, and that concentration and cognitive activity are not necessarily easier when the color temperature is high. The color temperature change when performing tasks promoted emotional factors more than brainwave, a biological change. PMID:26644662

  18. The effect of accelerated ageing on performance properties of addition type silicone biomaterials.

    PubMed

    Stathi, K; Tarantili, P A; Polyzois, G

    2010-05-01

    The UV-protection provided to addition type silicone elastomers by various colorants, such as conventional dry earth pigments, as well as the so called "functional or reactive" pigments, was investigated. Moreover, the effect of a UV light absorber and a silica filler was also explored. Under the experimental parameters of this work, the exposure of silicone to UV radiation resulted in some changes of the IR absorbance, thermal decomposition after 400 degrees C, T(g) and tensile properties, whereas the storage modulus of samples was not affected. The obtained spectroscopic data, as well as the results of TGA and storage modulus, were interpreted by assuming that chain scission takes place during aging, whereas the improvement of tensile strength allows the hypothesis of a post-curing process, initiated by UV radiation. Therefore, the increase of T(g) could partly be due to the above reason and, furthermore, to the contribution of a rearrangement of chain fragments within the free volume of the elastomeric material. Regarding the evaluation of various coloring agents used in this work, the obtained results show that dry pigments are more sensitive to accelerated ageing conditions in comparison with functional liquid pigments. Moreover, the hydrophobic character of silicone matrix is enhanced, with the addition of this type pigments because of the vinyl functional silanes groups present in their chemical structure. Finally, it should be noted that the incorporation of silica nanofiller did not seem to prevent the silicone elastomer from degradation upon UV irradiation, but showed a significant reinforcing effect.

  19. AC and lightning performance of fiberglass crossarms aged in 115 kV transmission line

    SciTech Connect

    Grzybowski, S. . Dept. of Electrical and Computer Engineering); Jenkins, E.B. . Generation and Transmission Group)

    1993-10-01

    This paper presents the results of an investigation of the electrical performance of 115 kV transmission line fiberglass cross-arm used by Mississippi Power and Light Company. A transmission line fiberglass crossarm removed from service and companion cross-arms outdoors but not in service were examined. The evaluation of electrical performance was based on flashover voltage value at AC voltage and standard lightning impulses as well as under dry and wet conditions. The tests were performed in the Mississippi State University High Voltage Laboratory. The obtained flashover voltages show no large differences in electrical strength of fiberglass crossarms removed from service and those stored outdoors. The Added CFO voltage by fiberglass crossarm to the porcelain suspension insulators is presented versus the length of the fiberglass crossarm for dry and wet conditions.

  20. Different age-dependent performance in Drosophila wild-type Canton-S and the white mutant w1118 flies.

    PubMed

    Qiu, Shuang; Xiao, Chengfeng; Meldrum Robertson, R

    2017-04-01

    Aging has significant effects on the locomotor performance of insects including Drosophila. Using a protocol for the high-throughput analysis of fly locomotion in a circular arena, we examined age-dependent behavioral characteristics in adult flies. There are widely used wild-type and genetically engineered background lines including the Canton-S strain and the w1118 strain, which has a null mutation of the white gene. Under standard rearing conditions, we found similar survival and median lifespans in Canton-S (50days) and w1118 (54days) strains, however, w1118 flies maintained stable body mass for up to 43days, whereas Canton-S flies gained body mass at young age, followed by a gradual decline. We also tested the behavioral performance of young and old flies. Compared with young w1118 flies (5-10days), old w1118 flies (40-45days) had an increased boundary preference during locomotion in small circular arenas, and increased speed of locomotor recovery from anoxia. Old Canton-S files, however, exhibited unchanged boundary preference and reduced recovery speed from anoxia relative to young flies. In addition, old w1118 flies showed decreased path length per minute and reduced 0.2s path increment compared with young flies, whereas old Canton-S flies displayed the same path length per minute and the same 0.2s path increment compared with young flies. We conclude that age-dependent behavioral and physiological changes differ between Canton-S and w1118 flies. These results illustrate that phenotypic differences between strains can change qualitatively, as well as quantitatively, as the animals age.

  1. Predicting plasticity: acute context-dependent changes to vocal performance predict long-term age-dependent changes

    PubMed Central

    James, Logan S.

    2015-01-01

    Understanding the factors that predict and guide variation in behavioral change can lend insight into mechanisms of motor plasticity and individual differences in behavior. The performance of adult birdsong changes with age in a manner that is similar to rapid context-dependent changes to song. To reveal mechanisms of vocal plasticity, we analyzed the degree to which variation in the direction and magnitude of age-dependent changes to Bengalese finch song could be predicted by variation in context-dependent changes. Using a repeated-measures design, we found that variation in age-dependent changes to the timing, sequencing, and structure of vocal elements (“syllables”) was significantly predicted by variation in context-dependent changes. In particular, the degree to which the duration of intersyllable gaps, syllable sequencing at branch points, and fundamental frequency of syllables within spontaneous [undirected (UD)] songs changed over time was correlated with the degree to which these features changed from UD song to female-directed (FD) song in young-adult finches (FDyoung). As such, the structure of some temporal features of UD songs converged over time onto the structure of FDyoung songs. This convergence suggested that the FDyoung song could serve as a stable target for vocal motor plasticity. Consequently, we analyzed the stability of FD song and found that the temporal structure of FD song changed significantly over time in a manner similar to UD song. Because FD song is considered a state of heightened performance, these data suggest that age-dependent changes could reflect practice-related improvements in vocal motor performance. PMID:26311186

  2. Ewe lambs with higher breeding values for growth achieve higher reproductive performance when mated at age 8 months.

    PubMed

    Nieto, C A Rosales; Ferguson, M B; Macleay, C A; Briegel, J R; Wood, D A; Martin, G B; Thompson, A N

    2013-09-15

    We studied the relationships among growth, body composition and reproductive performance in ewe lambs with known phenotypic values for depth of eye muscle (EMD) and fat (FAT) and Australian Sheep Breeding Values for post-weaning live weight (PWT) and depth of eye muscle (PEMD) and fat (PFAT). To detect estrus, vasectomized rams were placed with 190 Merino ewe lambs when on average they were 157 days old. The vasectomized rams were replaced with entire rams when the ewe lambs were, on average, 226 days old. Lambs were weighed every week and blood was sampled on four occasions for assay of ghrelin, leptin and ß-hydroxybutyrate. Almost 90% of the lambs attained puberty during the experiment, at an average live weight of 41.4 kg and average age of 197 days. Ewe lambs with higher values for EMD (P < 0.001), FAT (P < 0.01), PWT (P < 0.001), PEMD (P < 0.05) and PFAT (P < 0.05) were more likely to achieve puberty by 251 days of age. Thirty-six percent of the lambs conceived and, at the estimated date of conception, the average live weight was 46.9 ± 0.6 kg and average age was 273 days. Fertility, fecundity and reproductive rate were positively related to PWT (P < 0.05) and thus live weight at the start of mating (P < 0.001). Reproductive performance was not correlated with blood concentrations of ghrelin, leptin or ß-hydroxybutyrate. Many ewe lambs attained puberty, as detected by vasectomized rams, but then failed to become pregnant after mating with entire rams. Nevertheless, we can conclude that in ewe lambs mated at 8 months of age, higher breeding values for growth, muscle and fat are positively correlated with reproductive performance, although the effects of breeding values and responses to live weight are highly variable.

  3. Effects of age on the disruption of cognitive performance by exposure to space radiation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Exposure to low doses of heavy particles and protons can cause deficits in cognitive performance when measured within a short time (1-4 months) following irradiation. The long-term effects of such exposures and their relationship to the short-term effects remain to be established. The present exp...

  4. A Psychobiological Perspective on Working Memory Performance at 8 Months of Age

    ERIC Educational Resources Information Center

    Bell, Martha Ann

    2012-01-01

    Fifty 8-month-old infants participated in a study of the interrelations among cognition, temperament, and electrophysiology. Better performance on a working memory task (assessed using a looking version of the A-not-B task) was associated with increases in frontal-parietal EEG coherence from baseline to task, as well as elevated levels of…

  5. The ac and dc performance of polymeric insulating materials under accelerated aging in a fog chamber

    SciTech Connect

    Gorur, R.S. ); Cherney, E.A. ); Hackam, R. )

    1988-10-01

    The paper presents the results of the dc performance of polymeric insulating materials in a fog chamber. The materials evaluated in fog produced from low (250 ..mu..S/cm) and high (1000 ..mu..S/cm) conductivity water include cylindrical rod samples of high temperature vulcanized (HTV) silicone rubber and ethylene propylene diene monomer (EPDM) rubber containing various amounts of either alumina trihydrate (ATH) or silica fillers, or both. Comparison is made of material performance obtained with ac which was reported in an earlier study. In both low and high conductivity fog, the time to failure with ac and +dc was very similar, but a reduction by a factor of about four was observed in the time to failure with -dc. For both ac and dc, silicone rubber performed better than EPDM samples in low conductivity fog, while the order of performance was reversed in high conductivity fog. A theoretical model to determine the effect of dry band discharges on material is presented. Good agreement of the predicted behavior of materials with the experimental findings is shown.

  6. Motor Performance of Primary Age Handicapped and Nonhandicapped Children in the Mainstream: A Comparison.

    ERIC Educational Resources Information Center

    Sherrill, Claudine; Kelly, Luke

    A comparative study was made of mentally retarded and nonhandicapped children in the first through third grades on motor performance as measured by running (50-yard dash), jumping (standing broad jump), and throwing (softball throw for distance). The subjects had received all of their physical education instruction in a mainstream setting since…

  7. Age Differences in the Relationship between Visual Movement Imagery and Performance on Kinesthetic Acuity Tests.

    ERIC Educational Resources Information Center

    Livesey, David J.

    2002-01-01

    Investigated the relationship between Vividness of Movement Imagery Questionnaire scores and kinesthetic acuity--the sense of body position and movement--among 10- and 14-year-olds. Found that in the older group, those with high levels of visual movement imagery performed better on measures of kinesthetic acuity; no such effect was found for…

  8. Epilepsy in the School Aged Child: Cognitive-Behavioral Characteristics and Effects on Academic Performance.

    ERIC Educational Resources Information Center

    Black, Kathryn C.; Hynd, George W.

    1995-01-01

    Children with epilepsy frequently display cognitive sequelae that are overlooked or misunderstood by educational personnel, yet may adversely impact academic performance. Reviews common cognitive-behavioral characteristics of children with epilepsy, typical effects of anticonvulsant medications, and various periictal phenomena and their relative…

  9. The Presentation of Self in the Age of Social Media: Distinguishing Performances and Exhibitions Online

    ERIC Educational Resources Information Center

    Hogan, Bernie

    2010-01-01

    Presentation of self (via Goffman) is becoming increasingly popular as a means for explaining differences in meaning and activity of online participation. This article argues that self-presentation can be split into performances, which take place in synchronous "situations," and artifacts, which take place in asynchronous "exhibitions." Goffman's…

  10. A Comparative Study of Children's Concentration Performance on Picture Books: Age, Gender, and Media Forms

    ERIC Educational Resources Information Center

    Ma, Min-Yuan; Wei, Chun-Chun

    2016-01-01

    The reading development of children depends on various sensory stimuli, which help them construct reading contexts and facilitate active learning and exploration. This study uses sensory stimuli provided by picture books using various forms of media to improve children's concentration performance. We employ picture books using four forms of media:…

  11. Relation of Knowledge and Performance in Boys' Tennis: Age and Expertise.

    ERIC Educational Resources Information Center

    McPherson, Sue L.; Thomas, Jerry R.

    1989-01-01

    Examined 10- to 13-year-old boys' development of knowledge structure and sport performance in tennis by comparing skills and knowledge of experts and novices. Experts focused on higher concepts and exhibited greater decision-making ability because of their more highly developed knowledge structure. (SAK)

  12. Flexibly Global? Performing Culture and Identity in an Age of Uncertainty

    ERIC Educational Resources Information Center

    Giardina, Michael D.

    2009-01-01

    Presented as a symbolic interactive messy performance text, Michael Giardina sutures himself into and through the landscape of global social relations, including his own interpretive interactions of disconnection and reconnection with place, home, and nation. In so doing, and in these collages of lived textuality, he examines the complex,…

  13. Mental Rotation Performance in Primary School Age Children: Are There Gender Differences in Chronometric Tests?

    ERIC Educational Resources Information Center

    Jansen, P.; Schmelter, A.; Quaiser-Pohl, C.; Neuburger, S.; Heil, M.

    2013-01-01

    In contrast to the well documented male advantage in psychometric mental rotation tests, gender differences in chronometric experimental designs are still under dispute. Therefore, a systematic investigation of gender differences in mental rotation performance in primary-school children is presented in this paper. A chronometric mental rotation…

  14. Age, genotype and sex effects on growth performance of local chickens kept under improved management in Ghana.

    PubMed

    Osei-Amponsah, Richard; Kayang, Boniface B; Naazie, Augustine

    2012-01-01

    Characterisation of animal genetic resources has been recognised globally as an important step towards their sustainable use. Body weight data of local chickens (213 forest and 160 savannah chickens) and 183 French free-ranging SASSO T44 chickens kept under improved management were collected from hatch to 40 weeks of age and analysed to determine the effects of age, genotype and sex on their growth performance. At all ages, SASSO T44 chickens had significantly (P<0.05) higher weights (2.6-3.2 kg at 28 weeks) than the local chickens (1.2-1.7 kg at 28 weeks). The rate of growth at the earlier ages in the local genotypes (5.57-7.80 g/day) was lower than the range of 13.81-15.42 in SASSO T44 chickens. Except at hatch, savannah chickens were significantly heavier (P<0.05) than the forest chickens at all ages. Male chickens had significantly (P<0.05) superior growth rates than females across all genotypes except from the 20th to the 28th week. Growth trends in both sexes depicted linear increase in body weights; however, the rate of increase in body weights was higher in males as compared to females, thus showing clear sexual dimorphism. There were no significant (P>0.05) differences in the growth rates of SASSO T44 chickens and local genotypes at the later ages (20-28 weeks). Local chickens from the savannah zone had better growth rate than forest chickens. The significant effect of ecozone on the growth potential of local chickens is an indication that their productive potential could be improved through interventions in the environment such as provision of feed and some veterinary care.

  15. Evaluating elementary-aged students' abilities to generalize and maintain fluency gains of a performance feedback writing intervention.

    PubMed

    Hier, Bridget O; Eckert, Tanya L

    2014-12-01

    National estimates of students' writing abilities in the United States indicate that in 2002, 72% of elementary-aged students were unable to write with grade-level proficiency (Persky, Daane, & Jin, 2003). Although performance feedback is one type of intervention that improves students' writing skills, no study to date has examined the generalization and maintenance of writing fluency improvements developed through these interventions. The primary goal of this study was to determine whether elementary-aged students assigned to a performance feedback intervention condition demonstrated evidence of greater immediate treatment effects, generalization, and maintenance than students assigned to a practice-only condition. Results revealed that in comparison with the practice-only condition (n = 52), students assigned to the performance feedback condition (n = 51) demonstrated significantly greater immediate and generalized writing fluency improvements. However, evidence of maintenance of intervention effects was limited. These findings suggest that, in isolation, performance feedback may produce short-term desired effects on students' writing fluency growth, but that explicit programming of generality may be required to produce long-term achievement gains.

  16. The age-gender-status profile of high performing athletes in the UK taking nutritional supplements: Lessons for the future

    PubMed Central

    Petroczi, Andrea; Naughton, Declan P

    2008-01-01

    Background Owing to the mechanics of anti-doping regulation via the World Anti-Doping Agency's Prohibited List, nutritional supplement use received little attention in comparison to the prevalence of doping. The aims of this study were to investigate supplement use, identify groups of athletes with high levels of supplement use and the prevalence of concomitant use of supplements. Methods Survey data from 847 high-performing athletes in the UK were analysed using descriptive statistics. The survey, conducted by UK Sport, consisted of questions regarding knowledge of the prohibited substances, testing procedure, nutritional supplement use and perceptions of the doping problem. The proportion of supplement users and the relative use of each supplement were compared by age, gender and professional status. Results Among 874 high-performing athletes in the UK sample, 58.8% of them reported the use of at least one nutritional supplement. Among supplement users, 82.6% used more than one and 11.5% reported use of more than five nutritional supplements. Of the 9 supplements listed, multivitamins (72.6%) and vitamin C (70.7%) were used most, followed by creatine (36.1%), whey protein (31.7%), echinacea (30.9%), iron (29.9%) and caffeine (23.7%). Less than 11% reported the use of magnesium or ginseng. Creatine use was typically associated with males regardless of status and across all ages, whereas iron was characteristically used by females. A 'typical' supplement user is male, between 24 and 29 years of age, involved in professional sport and using a combination of supplements. Male professional players between age 30 and 34 years, and female non-professional athletes between 24 and 29 years of age also represented a considerable proportion of supplement users. Athletes older than 40 years of age were practically non-users. Concomitant use of supplements is characteristic of male users more than females. Conclusion As supplement use has been previously shown to increase the

  17. Age-related differences in the performance, diffusion, and maintenance of stone handling, a behavioral tradition in Japanese macaques.

    PubMed

    Leca, Jean-Baptiste; Gunst, Noëlle; Huffman, Michael A

    2007-12-01

    Identifying the sources of behavioral diversity in non-human primates is vital to understanding the evolution of human behavior. Stone handling (SH, hereafter) is a form of object play consisting of the manipulation of stones by performing various behavioral patterns. This behavior is socially transmitted from generation to generation in Japanese macaques (Macaca fuscata), as a behavioral tradition. SH behavior in particular may reflect on the origin and evolution of stone-tool material culture. The objective of this study was to assess how group size, age structure, and age- and sex-related differences may account for the substantial intra- and inter-troop variations in SH reported in ten troops of Japanese macaques. Our results supported the hypothesis that patterns of variation in SH across troops reflected variability in group size and composition in age classes. We found that troop size was correlated with the proportion of troop members exhibiting SH simultaneously. The effect of troop size on the synchronized performance of SH may reveal the contagious nature of play. Our results suggest that the age structure of the group may affect the diffusion of SH. As predicted by the surplus energy hypothesis, a major functional hypothesis about play, intra-group variation in SH reflected more age- than sex-related differences. SH mainly occurred and was more frequent in younger than in older individuals, whereas no significant sex differences were found. SH episodes were shorter, more vigorous, and SH patterns were more diverse and less complex in immature than in mature individuals. The present findings reveal that age-related factors and group size may constrain the performance, diffusion, and maintenance of SH within a troop. Contrary to most other socially transmitted stone-tool using behaviors in non-human primates and early hominids, there is no optimal SH pattern. Provided some form of social learning, the non-adaptive nature of SH may allow particular SH

  18. Modification of dichotic listening (DL) performance by musico-linguistic abilities and age.

    PubMed

    Milovanov, Riia; Tervaniemi, Mari; Takio, Fiia; Hämäläinen, Heikki

    2007-07-02

    To increase our understanding of the phonemic processing skills of musical and non-musical subjects, the Dichotic Listening task was performed in children and adults with varying degrees of musical aptitude. The roles of maturation and musical training were also investigated. The results showed superior left ear monitoring skills among the adults who practised music regularly. This may indicate altered hemispheric functioning. Other musically talented subjects did not have the ability to control left ear functioning in an equal manner, for instance, the performance of musical children and their non-musical controls in the forced-left / left ear condition did not differ. Thus, regular music practice may have a modulatory effect on the brain's linguistic organization and therefore, the beneficial effects of music on other cognitive skills should not be underestimated.

  19. Performances and failure of field-aged PV modules operating in Saharan region of Algeria

    NASA Astrophysics Data System (ADS)

    Sadok, M.; Benyoucef, B.; Othmani, M.; Mehdaoui, A.

    2016-07-01

    This article deals with behaviour of PV modules, of different technologies and manufacturers, exposed for long periods in Saharan region of Algeria. These modules are exposed in Adrar in the south-western part of Algeria. The study uses experimental I-V curves of PV modules for determining their performances. The datasheet information of modules will be useful in determination of degradation rates of the modules. Three types of modules have been tested: Photowatt (PWX 500), UDTS-50 and Isofoton (I-75 and I-100 serials). Results showed that Isofoton I-100 modules present the highest degradation rate while the lowest degradation rate was reached with I-75 serial. However, these rates tallies with other studies. The visual inspection of the modules has revealed various kinds of failures and defects responsible of performances drop (EVA browning, delamination, burn marks,…).

  20. The Evaluation of Reading Performance with Minnesota Low Vision Reading Charts in Patients with Age-related Macular Degeneration

    PubMed Central

    Altinbay, Deniz; Adibelli, Fatih Mehmet; Taskin, Ibrahim; Tekin, Adil

    2016-01-01

    PURPOSE: To evaluate the reading performance using the Minnesota low vision reading (MNREAD) charts, of patients with age-related macular degeneration (AMD) who use low vision aid (LVA) devices. MATERIALS AND METHODS: This prospective study enrolled 27 patients with AMD. Distance visual acuity (VA) was evaluated with a distance chart designed for patients with low vision. Near vision and reading performance were evaluated with the Turkish version of the MNREAD charts. Unaided vision and vision with LVA devices and high spherical add near glasses was measured. P <0.05 was considered statistically significant. RESULTS: The mean unaided near VA was 1.05 ± 0.27 log of the minimum angle of resolution (LogMAR). The mean VA with the LVA devices was 0.71 ± 0.41 LogMAR. Reading acuity ranged between 1.15 and 0.21 LogMAR, critical print size was between − 1.2 and 0.2 LogMAR. Maximum reading speeds were between 0 and 103 words/min. The cases are divided into groups in terms of reading speed according to age, gender, diagnosis, and education. Reading speed was negatively correlated to increasing age. CONCLUSION: MNREAD reading charts can be used to evaluate reading performance in patients with AMD with low vision. The outcomes of the present study indicate that optical correction is adequate for near VA requirements in this patient population. However, optical correction was inadequate for improving reading performance. Appropriate rehabilitation programs can be used to increase reading speed. PMID:27994393

  1. Visual performance in patients with neovascular age-related macular degeneration undergoing treatment with intravitreal ranibizumab.

    PubMed

    Sabour-Pickett, Sarah; Loughman, James; Nolan, John M; Stack, Jim; Pesudovs, Konrad; Meagher, Katherine A; Beatty, Stephen

    2013-01-01

    Purpose. To assess visual function and its response to serial intravitreal ranibizumab (Lucentis, Genentech) in patients with neovascular age-related macular degeneration (nv-AMD). Methods. Forty-seven eyes of 47 patients with nv-AMD, and corrected distance visual acuity (CDVA) logMAR 0.7 or better, undergoing intravitreal injections of ranibizumab, were enrolled into this prospective study. Visual function was assessed using a range of psychophysical tests, while mean foveal thickness (MFT) was determined by optical coherence tomography (OCT). Results. Group mean (±sd) MFT reduced significantly from baseline (233 (±59)) to exit (205 (±40)) (P = 0.001). CDVA exhibited no change between baseline and exit visits (P = 0.48 and P = 0.31, resp.). Measures of visual function that did exhibit statistically significant improvements (P < 0.05 for all) included reading acuity, reading speed, mesopic and photopic contrast sensitivity (CS), mesopic and photopic glare disability (GD), and retinotopic ocular sensitivity (ROS) at all eccentricities. Conclusion. Eyes with nv-AMD undergoing intravitreal ranibizumab injections exhibit improvements in many parameters of visual function. Outcome measures other than CDVA, such as CS, GD, and ROS, should not only be considered in the design of studies investigating nv-AMD, but also in treatment and retreatment strategies for patients with the condition.

  2. Visual Performance in Patients with Neovascular Age-Related Macular Degeneration Undergoing Treatment with Intravitreal Ranibizumab

    PubMed Central

    Loughman, James; Nolan, John M.; Stack, Jim; Pesudovs, Konrad; Meagher, Katherine A.; Beatty, Stephen

    2013-01-01

    Purpose. To assess visual function and its response to serial intravitreal ranibizumab (Lucentis, Genentech) in patients with neovascular age-related macular degeneration (nv-AMD). Methods. Forty-seven eyes of 47 patients with nv-AMD, and corrected distance visual acuity (CDVA) logMAR 0.7 or better, undergoing intravitreal injections of ranibizumab, were enrolled into this prospective study. Visual function was assessed using a range of psychophysical tests, while mean foveal thickness (MFT) was determined by optical coherence tomography (OCT). Results. Group mean (±sd) MFT reduced significantly from baseline (233 (±59)) to exit (205 (±40)) (P = 0.001). CDVA exhibited no change between baseline and exit visits (P = 0.48 and P = 0.31, resp.). Measures of visual function that did exhibit statistically significant improvements (P < 0.05 for all) included reading acuity, reading speed, mesopic and photopic contrast sensitivity (CS), mesopic and photopic glare disability (GD), and retinotopic ocular sensitivity (ROS) at all eccentricities. Conclusion. Eyes with nv-AMD undergoing intravitreal ranibizumab injections exhibit improvements in many parameters of visual function. Outcome measures other than CDVA, such as CS, GD, and ROS, should not only be considered in the design of studies investigating nv-AMD, but also in treatment and retreatment strategies for patients with the condition. PMID:23533703

  3. The effect of trehalose on the fermentation performance of aged cells of Saccharomyces cerevisiae.

    PubMed

    Trevisol, Eduardo T V; Panek, Anita D; Mannarino, Sergio Cantu; Eleutherio, Elis C A

    2011-04-01

    The fermentation process offers a wide variety of stressors for yeast, such as temperature, aging, and ethanol. To evaluate a possible beneficial effect of trehalose on ethanol production, we used mutant strains of Saccharomyces cerevisiae possessing different deficiencies in the metabolism of this disaccharide: in synthesis, tps1; in transport, agt1; and in degradation, ath1 and nth1. According to our results, the tps1 mutant, the only strain tested unable to synthesize trehalose, showed the lowest fermentation yield, indicating that this sugar is important to improve ethanol production. At the end of the first fermentation cycle, only the strains deficient in transport and degradation maintained a significant level of the initial trehalose. The agt1, ath1, and nth1 strains showed the highest survival rates and the highest proportions of non-petites. Accumulation of petites during fermentation has been correlated to low ethanol production. When recycled back for a subsequent fermentation, those mutant strains produced the highest ethanol yields, suggesting that trehalose is required for improving fermentative capacity and longevity of yeasts, as well as their ability to withstand stressful industrial conditions. Finally, according to our results, the mechanism by which trehalose improves ethanol production seems to involve mainly protection against protein oxidation.

  4. Adrafinil disrupts performance on a delayed nonmatching-to-position task in aged beagle dogs.

    PubMed

    Siwak, Christina T; Tapp, P Dwight; Milgram, Norton W

    2003-08-01

    Previous studies in humans and dogs have reported beneficial effects of adrafinil on specific cognitive functions. The effects in dogs are limited to a single study examining discrimination learning. We wanted to further explore the cognitive effects of adrafinil in dogs. The purpose of the present study was to determine the effect of oral administration of adrafinil on visuospatial function in dogs. Eighteen aged beagle dogs were tested on a delayed nonmatching-to-position (DNMP) task 2 h following one of three possible treatments; 20 mg/kg of adrafinil, 10 mg/kg of adrafinil or a placebo control. All dogs were tested under each treatment for eight test sessions. A 2-day washout period was given between treatments and the order of treatments was varied. Treatment with 20 mg/kg of adrafinil produced a significant impairment in working memory as indicated by an increase in the number of errors over the 8-day test period. The disturbance of memory functions from adrafinil could be a result of increased noradrenergic transmission in the prefrontal cortex.

  5. Analysis of participation and performance in athletes by age group in ultramarathons of more than 200 km in length

    PubMed Central

    Zingg, Matthias A; Knechtle, Beat; Rüst, Christoph A; Rosemann, Thomas; Lepers, Romuald

    2013-01-01

    Background Participation and performance trends for athletes by age group have been investigated for marathoners and ultramarathoners competing in races up to 161 km, but not for longer distances of more than 200 km. Methods Participation and performance trends in athletes by age group in the Badwater (217 km) and Spartathlon (246 km) races were compared from 2000 to 2012. Results The number of female and male finishers increased in both races across years (P < 0.05). The age of the annual five fastest men decreased in Badwater from 42.4 ± 4.2 years to 39.8 ± 5.7 years (r2 = 0.33, P = 0.04). For women, the age remained unchanged at 42.3 ± 3.8 years in Badwater (P > 0.05). In Spartathlon, the age of the annual five fastest finishers was unchanged at 39.7 ± 2.4 years for men and 44.6 ± 3.2 years for women (P > 0.05). In Badwater, running speed increased in men from 7.9 ± 0.7 km/hour to 8.7 ± 0.6 km/hour (r2 = 0.51, P < 0.01) and in women from 5.4 ± 1.1 km/hour to 6.6 ± 0.5 km/hour (r2 = 0.61, P < 0.01). In Spartathlon, running speed remained unchanged at 10.8 ± 0.7 km/hour in men and 8.7 ± 0.5 km/hour in women (P > 0.05). In Badwater, the number of men in age groups 30–34 years (r2 = 0.37, P = 0.03) and 40–44 years (r2 = 0.75, P < 0.01) increased. In Spartathlon, the number of men increased in the age group 40–44 years (r2 = 0.33, P = 0.04). Men in age groups 30–34 (r2 = 0.64, P < 0.01), 35–39 (r2 = 0.33, P = 0.04), 40–44 (r2 = 0.34, P = 0.04), and 55–59 years (r2 = 0.40, P = 0.02) improved running speed in Badwater. In Spartathlon, no change in running speed was observed. Conclusion The fastest finishers in ultramarathons more than 200 km in distance were 40–45 years old and have to be classified as “master runners” by definition. In contrast to reports of marathoners and ultramarathoners competing in races of 161 km in distance, the increase in participation and the improvement in performance by age group were less pronounced in

  6. The effect of body condition, live weight, breed, age, calf performance, and calving date on reproductive performance of spring-calving beef cows.

    PubMed

    Osoro, K; Wright, I A

    1992-06-01

    Data from 321 spring-calving cows (mean calving date March 27) were used to assess the effects of body condition, live weight, cow age (from 4 to 13 yr), and breed (237 Hereford x Friesians and 84 Blue-Greys) and time of calving on the proportion of cows that became pregnant, the number of days from the start of mating to pregnancy, and calving interval. Mating started at turn-out to pasture in mid-May and lasted 9 to 10 wk. Body condition at calving and breed were the most significant animal factors affecting reproductive performance. Cows calving in higher body condition had shorter (P less than .001) calving intervals (11.2 d per unit of body condition at calving). Blue-Grey cows became pregnant in a higher proportion (90%) and calving interval was shorter (364 d) than in Hereford x Friesians (83%; 374 d). Body condition at the start of mating was less important and body condition at the end of mating had no effect. Live weight at calving and changes in live weight from calving to the start of mating and during the mating period had no significant effect. The proportion of cows becoming pregnant decreased significantly with age in Hereford x Friesian cows older than 7 yr. The variance in calving interval accounted for by calving date, body condition at calving, breed, and age was 42%.

  7. Mitoxantrone, teniposide, chlorambucil and prednisone (MVLP) for relapsed non-Hodgkin's lymphoma. The impact of advanced age and performance status.

    PubMed

    Haak, H L; Gerrits, W B; Wijermans, P W; Kerkhofs, H

    1993-04-01

    Fifty-seven patients with relapsed non-Hodgkin's lymphoma (NHL) of low, intermediate and high-grade malignancy were treated with mitoxantrone, teniposide (Vm26), chlorambucil (Leukeran) and prednisone (MVLP). The median age was 71 years; none of the patients was excluded due to poor performance status (PS). Out of 44 patients with PS (according to WHO) < or = 2, 38 responded with a median progression free survival (PFS) of 21.5 months. Of 13 patients with PS > 2, 6 responded with a median PFS of 8.2 months. Haematopoietic toxicity was related to PS rather than to dose intensity or bone marrow involvement. Three patients died within a short time due to toxicity; another two died later as a result of cardiac failure probably due to accumulated toxicity of adriamycin and mitoxantrone. MVLP chemotherapy is effective and feasible and has only moderate toxicity in patients with relapsed NHL and PS < or = 2, despite advanced age.

  8. Thermal Performance of Aged and Weathered Spray-On Foam Insulation (SOFI) Materials Under Cryogenic Vacuum Conditions (Cryostat-4)

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The NASA Cryogenics Test Laboratory at Kennedy Space Center conducted long-term testing of SOFI materials under actual-use cryogenic conditions with Cryostat-4. The materials included in the testing were NCFI 24-124 (acreage foam), BX-265 (close-out foam, including intertank flange and bipod areas), and a potential alternate material, NCFI 27-68, (acreage foam with the flame retardant removed). Specimens of these materials were placed at two locations: a site that simulated aging (the Vehicle Assembly Building [VAB]) and a site that simulated weathering (the Atmospheric Exposure Test Site [beach site]). After aging/weathering intervals of 3, 6, and 12 months, the samples were retrieved and tested for their thermal performance under cryogenic vacuum conditions with test apparatus Cryostat-4.

  9. What is the age for the fastest ultra-marathon performance in time-limited races from 6 h to 10 days?

    PubMed

    Knechtle, Beat; Valeri, Fabio; Zingg, Matthias Alexander; Rosemann, Thomas; Rüst, Christoph Alexander

    2014-01-01

    Recent findings suggested that the age of peak ultra-marathon performance seemed to increase with increasing race distance. The present study investigated the age of peak ultra-marathon performance for runners competing in time-limited ultra-marathons held from 6 to 240 h (i.e. 10 days) during 1975-2013. Age and running performance in 20,238 (21%) female and 76,888 (79%) male finishes (6,863 women and 24,725 men, 22 and 78%, respectively) were analysed using mixed-effects regression analyses. The annual number of finishes increased for both women and men in all races. About one half of the finishers completed at least one race and the other half completed more than one race. Most of the finishes were achieved in the fourth decade of life. The age of the best ultra-marathon performance increased with increasing race duration, also when only one or at least five successful finishes were considered. The lowest age of peak ultra-marathon performance was in 6 h (33.7 years, 95% CI 32.5-34.9 years) and the highest in 48 h (46.8 years, 95% CI 46.1-47.5). With increasing number of finishes, the athletes improved performance. Across years, performance decreased, the age of peak performance increased, and the age of peak ultra-marathon performance increased with increasing number of finishes. In summary, the age of peak ultra-marathon performance increased and performance decreased in time-limited ultra-marathons. The age of peak ultra-marathon performance increased with increasing race duration and with increasing number of finishes. These athletes improved race performance with increasing number of finishes.

  10. Performance and Aging Studies of BaBar Resistive Plate Chambers

    SciTech Connect

    Band, H.R.; Hollar, J.; Tan, P.; Anulli, F.; Baldini, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Patteri, P.; Piccolo, M.; Zallo, A.; Cheng, C.H.; Lange, D.J.; Wright, D.M.; Messner, R.; Wisniewski, W.J.; Pappagallo, M.; Andreotti, M.; Bettoni, D.; Calabrese, R.; Cibinetto, G.; /Wisconsin U., Madison /Frascati /LLNL, Livermore /SLAC /Bari U. /INFN, Bari /Ferrara U. /INFN, Ferrara /Genoa U. /INFN, Genoa /Naples U. /INFN, Naples /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Rome U. /INFN, Rome /Oregon U. /UC, Riverside

    2006-10-13

    The BaBar detector is currently operating nearly 200 Resistive Plate Chambers (RPCs), constructed as part of an upgrade of the forward endcap muon detector in 2002. Although the average RPC efficiency remains high, numerous changes in the RPC performance (increased currents and rates) have been observed. A few of the highest rate RPCs have suffered efficiency losses of more than 15%. Several types of efficiency loss have been observed. Tests with humidified gas have shown that some of the lost efficiency is recoverable. However, efficiency losses in the highest rate regions have not yet improved with humid gases.

  11. Age-related hearing loss and ear morphology affect vertical but not horizontal sound-localization performance.

    PubMed

    Otte, Rik J; Agterberg, Martijn J H; Van Wanrooij, Marc M; Snik, Ad F M; Van Opstal, A John

    2013-04-01

    Several studies have attributed deterioration of sound localization in the horizontal (azimuth) and vertical (elevation) planes to an age-related decline in binaural processing and high-frequency hearing loss (HFHL). The latter might underlie decreased elevation performance of older adults. However, as the pinnae keep growing throughout life, we hypothesized that larger ears might enable older adults to localize sounds in elevation on the basis of lower frequencies, thus (partially) compensating their HFHL. In addition, it is not clear whether sound localization has already matured at a very young age, when the body is still growing, and the binaural and monaural sound-localization cues change accordingly. The present study investigated sound-localization performance of children (7-11 years), young adults (20-34 years), and older adults (63-80 years) under open-loop conditions in the two-dimensional frontal hemifield. We studied the effect of age-related hearing loss and ear size on localization responses to brief broadband sound bursts with different bandwidths. We found similar localization abilities in azimuth for all listeners, including the older adults with HFHL. Sound localization in elevation for the children and young adult listeners with smaller ears improved when stimuli contained frequencies above 7 kHz. Subjects with larger ears could also judge the elevation of sound sources restricted to lower frequency content. Despite increasing ear size, sound localization in elevation deteriorated in older adults with HFHL. We conclude that the binaural localization cues are successfully used well into later stages of life, but that pinna growth cannot compensate the more profound HFHL with age.

  12. The effect of high-speed strength training on physical performance in young soccer players of different ages.

    PubMed

    Rodriguez-Rosell, David; Franco-Márquez, Felipe; Mora-Custodio, Ricardo; González-Badillo, Juan José

    2016-10-28

    The aim of the present study was to compare the effectiveness of low-load, low-volume weight training combined with plyometrics on strength, sprint and jump performance in soccer players of different ages. Eighty-six soccer players from the same academy were categorized into 3 groups by age (under 13 year, U13, n = 30; under 15, U15, n = 28; under 17, U17, n = 28) and then randomly assigned into two subgroups: a strength training group (STG) and a control group (CG). The strength training program was performed twice a week for 6 weeks and consisted of full squats (load: 45-60% 1RM; volume: 3 set of 8-4 repetitions), jumps and straight line sprint exercises. After training intervention, the STGs showed significant improvements in maximal strength (7.5-54.5%; p < 0.001), jump height (5.7-12.5%; p < 0.01 - 0.001) and sprint time (-3.7 to -1.2%; p < 0.05 - 0.001), whereas no significant gains were found for any variable in the CGs. Comparison between experimental groups resulted in a greater magnitude of change for U13 compared to U15 (ES: 0.10-0.53) and U17 (ES: 0.14-1.41) soccer players in most variables, whereas U15 showed higher improvements in jump and strength parameters than U17 (ES: 0.25-0.90) soccer players. Thus, although our results indicates that a combined weight training and plyometrics program may be effective in eliciting gains in strength, jump and sprint in soccer players of different ages, the training program used appears to be generally less effective as the age of the soccer players increased. Therefore, it appears that training characteristics (mainly volume, intensity and type of exercise) should be modified in relation to maturity status and initial strength level.

  13. Novel inflammatory markers associated with cognitive performance: Singapore Longitudinal Ageing Studies.

    PubMed

    Gao, Qi; Camous, Xavier; Lu, Yan-Xia; Lim, May-Li; Larbi, Anis; Ng, Tze-Pin

    2016-03-01

    We identified and validated several novel inflammatory markers of cognitive performance in community-living older persons. An exploratory study (n = 83) correlated 177 inflammatory markers assayed by Luminex with the Mini-Mental State Examination (MMSE) and identified 8 inflammatory markers for enzyme-linked immunosorbent assay (ELISA) and correlations with MMSE, Montreal Cognitive Assessment (MoCA), and cognitive impairment in the validation study (n = 139). The validation study replicated the significant associations of soluble interleukin-2 receptor alpha chain (sIL-2Rα; p = 0.050), soluble tumor necrosis factor receptor 2 (sTNFR2; p = 0.002) and soluble glycoprotein 130 (sgp130; p = 0.026) with MMSE, and sIL-2Rα (p = 0.019) and sgp130 (p < 0.001) with MoCA. Significant trends of associations of tertiles of sgp130, sIL-2Rα, and sTNFR2 were found with cognitive impairment. Highly elevated estimates of association of high versus low tertiles were obtained for sgp130 (odds ratio [OR] = 4.24, 95% confidence interval [CI] 0.96-18.8), sIL-2Rα (OR = 3.94, 95% CI 0.83-18.7), and sTNFR2 (OR = 7.58, 95% CI 1.19-48.1). sgp130, sTNFR2, and sIL-2Rα are promising inflammatory markers of low cognitive performance for further investigation.

  14. Hunting behaviour and breeding performance of northern goshawks Accipiter gentilis, in relation to resource availability, sex, age and morphology

    NASA Astrophysics Data System (ADS)

    Penteriani, Vincenzo; Rutz, Christian; Kenward, Robert

    2013-10-01

    Animal territories that differ in the availability of food resources will require (all other things being equal) different levels of effort for successful reproduction. As a consequence, breeding performance may become most strongly dependent on factors that affect individual foraging where resources are poor. We investigated potential links between foraging behaviour, reproductive performance and morphology in a goshawk Accipiter gentilis population, which experienced markedly different resource levels in two different parts of the study area (rabbit-rich vs. rabbit-poor areas). Our analyses revealed (1) that rabbit abundance positively affected male reproductive output; (2) that age, size and rabbit abundance (during winter) positively affected different components of female reproductive output; (3) that foraging movements were inversely affected by rabbit abundance for both sexes (for females, this may mainly have reflected poor provisioning by males in the rabbit-poor area); (4) that younger breeders (both in males and females) tended to move over larger distances than older individuals (which may have reflected both a lack of hunting experience and mate searching); and (5) that male body size (wing length) showed some covariation with resource conditions (suggesting possible adaptations to hunting agile avian prey in the rabbit-poor area). Although we are unable to establish firm causal relationships with our observational data set, our results provide an example of how territory quality (here, food abundance) and individual features (here, age and morphology) may combine to shape a predator's foraging behaviour and, ultimately, its breeding performance.

  15. Effects of age and spa treatment on match running performance over two consecutive games in highly trained young soccer players.

    PubMed

    Buchheit, Martin; Horobeanu, Cosmin; Mendez-Villanueva, Alberto; Simpson, Ben M; Bourdon, Pitre C

    2011-03-01

    The aim of this study was to examine the effect of age and spa treatment (i.e. combined sauna, cold water immersion, and jacuzzi) on match running performance over two consecutive matches in highly trained young soccer players. Fifteen pre- (age 12.8 ± 0.6 years) and 13 post- (15.9 ± 1 y) peak height velocity (PHV) players played two matches (Matches 1 and 2) within 48 h against the same opposition, with no specific between-match recovery intervention (control). Five post-PHV players also completed another set of two consecutive matches, with spa treatment implemented after the first match. Match running performance was assessed using a global positioning system with very-high-intensity running (> 16.1-19.0 km · h(-1)), sprinting distance (>19 km · h(-1)), and peak match speed determined. Match 2 very-high-intensity running was "possibly" impaired in post-PHV players (-9 ± 33%; ± 90% confidence limits), whereas it was "very likely" improved for the pre-PHV players (+27 ± 22%). The spa treatment had a beneficial impact on Match 2 running performance, with a "likely" rating for sprinting distance (+30 ± 67%) and "almost certain" for peak match speed (+6.4 ± 3%). The results suggest that spa treatment is an effective recovery intervention for post-PHV players, while its value in pre-PHV players is questionable.

  16. Skeletal muscle myofilament adaptations to aging, disease, and disuse and their effects on whole muscle performance in older adult humans

    PubMed Central

    Miller, Mark S.; Callahan, Damien M.; Toth, Michael J.

    2014-01-01

    Skeletal muscle contractile function declines with aging, disease, and disuse. In vivo muscle contractile function depends on a variety of factors, but force, contractile velocity and power generating capacity ultimately derive from the summed contribution of single muscle fibers. The contractile performance of these fibers are, in turn, dependent upon the isoform and function of myofilament proteins they express, with myosin protein expression and its mechanical and kinetic characteristics playing a predominant role. Alterations in myofilament protein biology, therefore, may contribute to the development of functional limitations and disability in these conditions. Recent studies suggest that these conditions are associated with altered single fiber performance due to decreased expression of myofilament proteins and/or changes in myosin-actin cross-bridge interactions. Furthermore, cellular and myofilament-level adaptations are related to diminished whole muscle and whole body performance. Notably, the effect of these various conditions on myofilament and single fiber function tends to be larger in older women compared to older men, which may partially contribute to their higher rates of disability. To maintain functionality and provide the most appropriate and effective countermeasures to aging, disease, and disuse in both sexes, a more thorough understanding is needed of the contribution of myofilament adaptations to functional disability in older men and women and their contribution to tissue level function and mobility impairment. PMID:25309456

  17. Effects of maternal dietary EPA and DHA supplementation and breeder age on embryonic and post-hatch performance of broiler offspring: age and n-3 pufa affect embryonic and post-hatch performance.

    PubMed

    Koppenol, A; Delezie, E; Wang, Y; Franssens, L; Willems, E; Ampe, B; Buyse, J; Everaert, N

    2015-04-01

    Breeder age and nutrition are amongst the most important factors affecting progeny growth and development. The present experiment was carried out to evaluate the effects of n-3 fatty acid (FA), with special emphasis on the ratio of eicosapentaenoic (EPA, 20:5 n-3) and docosahexaenoic (DHA, 22:6 n-3) acid, provided to the diet of ageing broiler breeder hens at different ratios, on the incubation parameters and the performance of the offspring. Four hundred and eighty Ross-308 broiler breeder hens were fed one of four different diets (120/treatment), with an equal fat content. The control diet was a basal diet, rich in n-6 FAs (CON). Blends of fish oil were used to enrich the three other diets in n-3 FA and to obtain different EPA/DHA ratios of 1/1 (EPA=DHA), 1/2 (DHA) or 2/1 (EPA). Every 5 weeks, incubation parameters were assessed. Every 15 weeks, offspring was reared until slaughter age on a standard diet. Breeder age affected almost all incubation and post-hatch parameters, whereas n-3 FA treatment only lowered egg weight (p < 0.0001) and consequently hatched chick weight (p < 0.0001). Supplementation of EPA resulted in a higher proportional liver weight (p = 0.0219) at hatch, a lower body weight up to 28 days post-hatch (p = 0.0418), a lower daily weight gain (p = 0.0498) and a higher feed conversion ratio (p = 0.0395) during the starter period (p = 0.0498), resulting in a higher overall offspring feed conversion ratio (p = 0.0317) compared to the control diet. DHA supplementation, on the other hand, resulted in a lower residual yolk weight (p = 0.0220) and a higher overall offspring mortality (p = 0.0125). In conclusion, supplementation of n-3 FA could not counter the adverse effect of breeder flock age, but did not harm incubation or improve post-hatch performance, either. EPA and DHA affected offspring development differently during early post-hatch life.

  18. Forage and sugar in dairy calves' starter diet and their interaction on performance, weaning age and rumen fermentation.

    PubMed

    Beiranvand, H; Ghorbani, G R; Khorvash, M; Kazemi-Bonchenari, M

    2014-06-01

    The effects of sugar and forage inclusion in calves' starter and their interaction on animal performance and rumen fermentation parameters were investigated. Twenty-eight neonatal Holstein male calves 3 days of age with average body weights of 42 ± 4 kg were allocated to four different treatments. All calves were fed a similar basal diet consisting of milk and concentrate. The experimental treatments were: (i) basal diet with no supplementation (Control, hereafter designated by C), (ii) basal diet plus 5% granular sugar cane (Sugar, designated by S), (iii) basal diet plus 5% forage (Forage, designated by F) and (iv) basal diet plus 5% forage with 5% granular sugar cane (F × S). Supplement ingredients were used on a dry matter (DM) basis. Rumen fluid parameters were measured twice on days 35 and 70 of the study period. The calves were weaned when they could consume 1 kg of starter for three consecutive days. The results show that starter intake was not affected by treatment; however, the lowest ADG was observed with calves in the sugar treatment. Weaning age was affected by treatments, and forage showed to reduce milk consumption period down to its shortest. Forage-sugar interaction was found to have no effects on animal performance. The structural body indices as well as the health status of the calves were similar in different treatments. Rumen pH did not differ among the treatment groups. Among the rumen parameters, total VFA concentration and molar proportions of butyrate and propionate did not exhibit any significant differences among the treatments. However, ruminal acetate concentration decreased in calves that fed sugar cane during the early weeks of the study period. Comparison of forage and sugar included in the starter diets revealed that forage reduced weaning age, while sugar cane had a negative effect on calves' performance.

  19. Implicit motor sequence learning in schizophrenia and in old age: reduced performance only in the third session.

    PubMed

    Cornelis, Claudia; De Picker, Livia J; De Boer, Peter; Dumont, Glenn; Coppens, Violette; Morsel, Anne; Janssens, Luc; Timmers, Maarten; Sabbe, Bernard G C; Morrens, Manuel; Hulstijn, Wouter

    2016-12-01

    Although there still is conflicting evidence whether schizophrenia is a neurodegenerative disease, cognitive changes in schizophrenia resemble those observed during normal aging. In contrast to extensively demonstrated deficits in explicit learning, it remains unclear whether implicit sequence learning is impaired in schizophrenia and normal aging. Implicit sequence learning was investigated using a computerized drawing task, the 'implicit pattern learning task (IPLT)' in 30 stable patients with schizophrenia, 30 age-matched controls and 30 elderly subjects on two consecutive days and after 1 week (sessions 1, 2 and 3). Fixed sequence trials were intermixed with random trials, and sequence learning was assessed by subtraction of the response time in fixed sequence trials from random trials. Separate analyses of response times and movement accuracy (i.e., directional errors) were performed. Explicit sequence knowledge was assessed using three different awareness tasks. All groups learned equally during sessions 1 and 2. In session 3, control subjects showed significantly larger learning scores than patients with schizophrenia (p = .012) and elderly subjects (p = .021). This group difference is mainly expressed in movement time and directional errors. Patients with schizophrenia demonstrated less subjective sequence awareness, and both patients with schizophrenia and elderly subjects had less explicit sequence recall. Explicit recall was positively correlated with task performance in all groups. After a short 24 h interval, all subjects showed similar improvements in implicit sequence learning. However, no benefit of prior task exposure 1 week later was observed in patients with schizophrenia and elderly subjects compared to controls. As patients with schizophrenia and elderly both display less explicit sequence recall, the control group superiority after 1 week could be explained by an explicit learning component. The few patients with schizophrenia and

  20. Modeling population health: reflections on the performativity of epidemiological techniques in the age of genomics.

    PubMed

    Bauer, Susanne

    2013-12-01

    Risk reasoning has become the common-sense mode of knowledge production in the health sciences. Risk assessment techniques of modern epidemiology also co-shape the ways genomic data are translated into population health. Risk computations (e.g., in preventive medicine, clinical decision-support software, or web-based self-tests), loop results from epidemiological studies back into everyday life. Drawing from observations at various European research sites, I analyze how epidemiological techniques mediate and enact the linkages between genomics and public health. This article examines the epidemiological apparatus as a generative machine that is socially performative. The study design and its reshuffling of data and categories in risk modeling recombine old and new categories from census to genomics and realign genes/environment and nature/culture in novel and hybrid ways. In the Euro-American assemblage of risk reasoning and related profiling techniques, the individual and the population are no longer separate but intimately entangled.

  1. Single and repeated exposures to the volatile anesthetic isoflurane do not impair operant performance in aged rats.

    PubMed

    Walters, Jennifer L; Chelonis, John J; Fogle, Charles M; Orser, Beverley A; Paule, Merle G

    2016-09-01

    Postoperative Cognitive Dysfunction (POCD) is a complication that can occur in the elderly after anesthesia and surgery and is characterized by impairments in information processing, memory, and executive function. Currently, it is unclear whether POCD is due to the effects of surgery, anesthesia, or perhaps some interaction between these or other perioperative variables. Studies in rodents suggest that the development of POCD may be related directly to anesthesia-induced neuroactivity. Volatile anesthetics have been shown to increase cellular inflammation and apoptosis within the hippocampus of aged rodents, while producing corresponding impairments in hippocampal-dependent brain functions. However, it is unclear whether volatile anesthetics can affect additional aspects of cognition that do not primarily depend upon the hippocampus. The purpose of this study was to use established operant tests to examine the effects of isoflurane on aspects of behavioral inhibition, learning, and motivation in aged rats. Twenty-one adult Sprague-Dawley rats (11 male, 10 female) were trained to perform fixed consecutive number (FCN), incremental repeated acquisition (IRA), and progressive ratio (PR) tasks for a minimum of 15 months prior to receiving anesthesia. At 23 months of age, rats were exposed to 1.3% isoflurane or medical grade air for 2h. Initial results revealed that a 2h exposure to isoflurane had no effect on IRA, FCN, or PR performance. Thus, rats received 3 additional exposures to 1.3% isoflurane or medical grade air: 2, 4 and 6h exposures with 2 weeks elapsing before exposure two, 3 weeks elapsing between exposures two and three, and 2 weeks elapsing between exposures three and four. These additional exposures had no observable effects on performance of any operant task. These results suggest that single and repeated exposures to isoflurane do not impair the performance of aged rats in tasks designed to measure behavioral inhibition, learning, and motivation. This

  2. Prepartum supplement level and age at weaning: I. Effects on pre- and postpartum beef cow performance and calf performance through weaning.

    PubMed

    Shoup, L M; Kloth, A C; Wilson, T B; González-Peña, D; Ireland, F A; Rodriguez-Zas, S; Felix, T L; Shike, D W

    2015-10-01

    Objectives were to determine the interaction of prepartum supplement level and age at weaning on cow BW, BCS, milk production, reproduction, and calf performance up to weaning in a fall-calving system over 2 yr. Mature, multiparous, Angus × Simmental cows (yr 1: 326 cows, 9 pastures, BW = 632 ± 67 kg, and BCS = 5.7 ± 0.58; yr 2: 383 cows, 9 pastures, BW = 606 ± 70 kg, and BCS = 5.8 ± 0.74) were used in a split-plot design that included 3 supplement levels-no supplement (NS), low supplement (LS; 2.16 kg∙cow∙d), or high supplement (HS; 8.61 kg∙cow∙d)-and 2 ages at weaning-78 ± 11 d of age (early weaned; EW) or 186 ± 11 d of age (normal weaned; NW). Cows grazed endophyte-infected tall fescue/red clover pastures and were bunk fed supplement (70% dried distillers' grains with solubles and 30% soybean hulls) 103 ± 11 d prepartum to 2 ± 11 d postpartum. Cow BW was greater ( < 0.01) for cows fed HS at precalving (49 ± 11 d prepartum), postcalving (26 ± 11 d postpartum), and postbreeding (81 d after AI) compared with cows fed NS and LS. Prepartum supplementation did not affect ( ≥ 0.62) calf birth BW, percent of calves dead at birth, or percent of cows calving unassisted. Prepartum supplementation tended ( = 0.10) to improve AI conception. Early weaning increased ( ≤ 0.05) AI conception and postbreeding cow BW and BCS compared with cows with NW calves. Neither prepartum supplementation nor age at weaning affected ( ≥ 0.28) overall pregnancy rate. At time of early weaning, BW was increased ( = 0.05) for steers from cows fed LS compared with steers from cows fed NS. Steer BW at time of normal weaning and ADG between early and normal weaning was greater ( < 0.01) for EW steers compared with NW steers. A year × age at weaning interaction occurred ( < 0.01) for ultrasound marbling score at time of normal weaning. In yr 1, marbling was decreased ( = 0.04) for EW steers compared with NW steers; however, in yr 2, marbling was increased ( < 0.01) for EW

  3. Telomere Length and CCL11 Levels are Associated With Gray Matter Volume and Episodic Memory Performance in Schizophrenia: Evidence of Pathological Accelerated Aging.

    PubMed

    Czepielewski, Leticia Sanguinetti; Massuda, Raffael; Panizzutti, Bruna; Grun, Lucas Kich; Barbé-Tuana, Florencia María; Teixeira, Antonio Lucio; Barch, Deanna M; Gama, Clarissa S

    2017-02-22

    Schizophrenia (SZ) is associated with increased somatic morbidity and mortality, in addition to cognitive impairments similar to those seen in normal aging, which may suggest that pathological accelerated aging occurs in SZ. Therefore, we aim to evaluate the relationships of age, telomere length (TL), and CCL11 (aging and inflammatory biomarkers, respectively), gray matter (GM) volume and episodic memory performance in individuals with SZ compared to healthy controls (HC). One hundred twelve participants (48 SZ and 64 HC) underwent clinical and memory assessments, structural MRI, and had their peripheral blood drawn for biomarkers analysis. Comparisons of group means and correlations were performed. Participants with SZ had decreased TL and GM volume, increased CCL11, and worse memory performance compared to HC. In SZ, shorter TL was related to increased CCL11, and both biomarkers were related to reduced GM volume, all of which were related to worse memory performance. Older age was only associated with reduced GM, but longer duration of illness was related with all the aforementioned variables. Younger age of disease onset was associated with increased CCL11 levels and worse memory performance. In HC, there were no significant correlations except between memory and GM. Our results are consistent with the hypothesis of accelerated aging in SZ. These results may indicate that it is not age itself, but the impact of the disease associated with a pathological accelerated aging that leads to impaired outcomes in SZ.

  4. Chronic estradiol replacement to aged female rats reduces anxiety-like and depression-like behavior and enhances cognitive performance.

    PubMed

    Walf, Alicia A; Paris, Jason J; Frye, Cheryl A

    2009-07-01

    Decline in the ovarian steroid, estradiol (E(2)), with the menopause transition may influence cognitive and affective processing of older women and there is evidence that hormone replacement therapies (HRTs) with E(2)-mimetics may provide benefit in some, but not all, women. The parameters that play a role in determining whether the response to HRTs is positive are of interest. It may be that the likelihood for positive responses is related to the timing of E(2)-replacement following E(2) decline. As such, in the present study an animal model was utilized to investigate this. We investigated the effects of long- versus short-term E(2)-replacement by examining cognitive (object placement task), anxiety (open field, mirror maze, light-dark transition task), and depression (forced swim task) behavior of female rats that were ovariectomized (OVX) at middle-age (14 months) or older (19 months) and implanted with E(2)-filled implants at the time of surgery or after a delay of 5 months, or OVX at 14 months of age and never replaced with E(2). Rats were tested at 20 months of age. The hypothesis that was tested was that rats would have reduced anxiety and depression behavior and improved cognitive performance with E(2)-replacement at ovarian cessation, compared to a delay in E(2)-replacement. Performance in the object placement task was improved in rats that were OVX and then received continuous E(2)-replacement, compared to those that were OVX and continuously administered placebo vehicle. In the open field and forced swim task, there was an increase in anti-anxiety and anti-depression behavior, respectively, among rats that were OVX and then received continuous E(2)-replacement, compared to OVX rats administered vehicle or those that experienced a delay in E(2)-replacement. In the mirror maze and light-dark transition task, E(2)-replacement at OVX, or after a delay, reduced anxiety-like behavior. Thus, E(2)-replacement reduced anxiety and depression behavior and improved

  5. Diagnosing dementia and normal aging: clinical relevance of brain ratios and cognitive performance in a Brazilian sample.

    PubMed

    Chaves, M L; Ilha, D; Maia, A L; Motta, E; Lehmen, R; Oliveira, L M

    1999-09-01

    The main objective of the present study was to evaluate the diagnostic value (clinical application) of brain measures and cognitive function. Alzheimer and multi-infarct patients (N = 30) and normal subjects over the age of 50 (N = 40) were submitted to a medical, neurological and cognitive investigation. The cognitive tests applied were Mini-Mental, word span, digit span, logical memory, spatial recognition span, Boston naming test, praxis, and calculation tests. The brain ratios calculated were the ventricle-brain, bifrontal, bicaudate, third ventricle, and suprasellar cistern measures. These data were obtained from a brain computer tomography scan, and the cutoff values from receiver operating characteristic curves. We analyzed the diagnostic parameters provided by these ratios and compared them to those obtained by cognitive evaluation. The sensitivity and specificity of cognitive tests were higher than brain measures, although dementia patients presented higher ratios, showing poorer cognitive performances than normal individuals. Normal controls over the age of 70 presented higher measures than younger groups, but similar cognitive performance. We found diffuse losses of tissue from the central nervous system related to distribution of cerebrospinal fluid in dementia patients. The likelihood of case identification by functional impairment was higher than when changes of the structure of the central nervous system were used. Cognitive evaluation still seems to be the best method to screen individuals from the community, especially for developing countries, where the cost of brain imaging precludes its use for screening and initial assessment of dementia.

  6. The Effect of an 8-Week Tai Chi Exercise Program on Physical Functional Performance in Middle-Aged Women.

    PubMed

    Zacharia, Susan; Taylor, E Laurette; Hofford, Craig W; Brittain, Danielle R; Branscum, Paul W

    2015-08-01

    The purpose of this study was to determine the effectiveness of an 8-week Tai Chi Chih exercise program on physical functional performance (PFP) among women aged 45 to 65 years. A quasi-experimental design with a nonequivalent comparison group was used. Forty-one healthy inactive women were assigned to either an intervention group (n = 19) or a comparison group (n = 19). A 60-min Tai Chi Chih exercise class was conducted twice a week for 8 weeks. PFP was measured at baseline and postintervention using the Continuous Scale Physical Functional Performance-10 (CS-PFP 10). Between-group differences were analyzed using one-way analysis of covariance (ANCOVA). After participating in the 8-week program, intervention group participants showed greater improvement in the CS-PFP measures (p < .05, η(2) > .06). However, the comparison group had little changes. The findings from this study suggest that participation in an 8-week Tai Chi Chih exercise program can improve PFP in healthy, community-dwelling middle-aged women.

  7. Special education services and school performance in a regional cohort of low-birthweight infants at age nine.

    PubMed

    Pinto-Martin, Jennifer; Whitaker, Agnes; Feldman, Judith; Cnaan, Avital; Zhao, Huaqing; Bloch, Joan Rosen; Rosen-Bloch, Joan; McCulloch, Dawn; Paneth, Nigel

    2004-03-01

    Previous research has shown that low birthweight is a predictor of several adverse educational outcomes, including special educational placement, by middle school age. Most low-birthweight follow-up studies that have extended to school age have focused on very small infants-- < 1500 or < 1000 g; less is known of the school age outcomes for infants with only moderately low birthweight (1500-2000 g). This study examines the prevalence of special educational placement and the relationship of such placement to grade retention, verbal and performance scores on tests of general intelligence, reading and maths achievement scores and classroom hyperactivity among low-birthweight children. In a regional birth cohort of 1105 infants born between 1984 and 1987 and weighing 500-2000 g, 868 children were available for follow-up at age nine. Information on special education placement as well as grade retention, intelligence, academic achievement and classroom behaviour was available on 645 (74% completion rate). Nearly a third of the cohort was classified as needing special education. Special education placement followed a birthweight gradient, occurring among 29.3% of children with birthweights 1500-2000 g, among 32.5% in children 1000-1500 g and 49.4% in children < 1000 g. Among children in special education, a similar birthweight gradient was found for maths achievement and hyperactivity, but not for reading achievement or IQ scores. Among children not in special education, only maths achievement showed such a decline with birthweight. A substantial proportion of low-birthweight children, including those of moderate low birthweight, receive special education services, although the need is greatest among those with the lowest birthweights. Maths achievement declined with birthweight regardless of educational placement. The medical and social risk factors that accompany low birthweight and may account for these findings, require further study.

  8. Depth-dependent variations in Achilles tendon deformations with age are associated with reduced plantarflexor performance during walking.

    PubMed

    Franz, Jason R; Thelen, Darryl G

    2015-08-01

    The anatomical arrangement of the Achilles tendon (AT), with distinct fascicle bundles arising from the gastrocnemius and soleus muscles, may facilitate relatively independent behavior of the triceps surae muscles. A reduced capacity for sliding between adjacent tendon fascicles with age may couple gastrocnemius and soleus muscle behavior, thereby potentially contributing to diminished plantarflexor performance commonly observed in old adults. Nine healthy young (mean age, 23.9 yr) and eight healthy old (69.9 yr) adults walked at three speeds (0.75, 1.00, and 1.25 m/s) on a force-sensing treadmill. We coupled dynamic ultrasound imaging of the free AT with motion capture and inverse dynamic analyses to compute, in part: 1) depth-dependent variations in AT tissue displacements and elongations and 2) net ankle joint kinetics during push-off. The difference in displacements between superficial and deep AT regions, and in their corresponding elongations, did not differ between old and young adults at the slower two walking speeds (P > 0.61). However, old adults walked with 41% smaller depth-dependent variations in free AT displacements and elongations at 1.25 m/s (P = 0.02). These more uniform tendon deformations in old adults most strongly correlated with reduced peak ankle moment (R(2) = 0.40), but also significantly correlated with reduced peak power generation (R(2) = 0.15) and positive ankle work during push-off (R(2) = 0.19) (P > 0.01). Our findings: 1) demonstrate a potential role for nonuniform AT deformations in governing gastrocnemius and soleus muscle-tendon function and 2) allude to altered tendon behavior that may contribute to the age-related reduction in plantarflexor performance during walking.

  9. Associations between strain, herd size, age at first calving, culling reason and lifetime performance characteristics in Holstein-Friesian cows.

    PubMed

    Adamczyk, K; Makulska, J; Jagusiak, W; Węglarz, A

    2017-02-01

    Cow longevity and lifetime performance traits are good indicators of breeding effectiveness and animal welfare. They are also interrelated with the economics of dairy herd. Unfortunately, a high milk yield is often associated with deteriorated cow health and fertility and, consequently, with an increased culling rate. This situation, observed also in the Polish population of Holstein-Friesian cattle, inspired us to undertake a study on the associations between some factors and lifetime performance characteristics. The data set consisted of the records on 135 496 cows, including 131 526 of the Black and White strain (BW), and 3970 of the Red and White strain (RW) covered by performance recording and culled in 2012. It was found that cows of the BW strain and those from the largest herds (>100 cows) reached higher lifetime and mean daily energy-corrected milk (ECM) yields than cows of the RW strain and those from smaller herds culled at a similar age. Cows youngest at first calving (<2.0 years) were characterised by the highest lifetime ECM yield. It indicates that heifers can be bred even when they are younger than 15 to 16 months with no significant negative effect on their later performance. Infertility and reproduction problems (39.6%) and udder diseases (15.5%) constituted the most frequent reasons for cow culling. Cow longevity and lifetime productivity were considerably affected by the interactions between the studied factors.

  10. Supramaximal intermittent running performance in relation to age and locomotor profile in highly-trained young soccer players.

    PubMed

    Buchheit, Martin; Mendez-Villanueva, Alberto

    2013-01-01

    The aim of the study was to examine supramaximal intermittent running performance in highly-trained young soccer players, with regard to age and locomotor profile. Twenty-seven Under 14, 19 U16 and 16 U18 highly-trained soccer players performed an incremental intermittent running test (30-15 Intermittent Fitness Test) to assess supramaximal intermittent running performance (VIFT), an incremental running test to estimate maximal aerobic speed (VVam-Eval) and a 40-m sprint to estimate maximal sprinting speed (MSS). U16 and U18 presented very likely greater VIFT (19.2 ± 0.9, 19.7 ± 1.0 vs. 17.4 ± 0.9 km · h(-1)) and VVam-Eval (16.2 ± 0.9, 16.7 ± 1.0 vs. 14.6 ± 0.9 km · h(-1)) than U14, while there was no clear difference between U16 and U18. MSS (25.1 ± 1.6, 29.3 ± 1.6 and 31.0 ± 1.1 km · h(-1) for U14, U16 and U18) was very likely different between all groups. When data were pooled together, VIFT was very largely correlated with VVam-Eval and MSS (overall r =0.89, partial r = 0.74 and 0.29, respectively). Within-age group correlations showed that the older the players, the greater the magnitude of the correlations between VIFT and VVam-Eval (r = 0.67, 0.73 and 0.87). In conclusion, the major predictors of VIFT were, in order of importance, VVam-Eval and MSS; however, the older the players, the greater the correlations with VVam-Eval.

  11. Performance and agreement of risk stratification instruments for postoperative delirium in persons aged 50 years or older.

    PubMed

    Jansen, Carolien J; Absalom, Anthony R; de Bock, Geertruida H; van Leeuwen, Barbara L; Izaks, Gerbrand J

    2014-01-01

    Several risk stratification instruments for postoperative delirium in older people have been developed because early interventions may prevent delirium. We investigated the performance and agreement of nine commonly used risk stratification instruments in an independent validation cohort of consecutive elective and emergency surgical patients aged ≥50 years with ≥1 risk factor for postoperative delirium. Data was collected prospectively. Delirium was diagnosed according to DSM-IV-TR criteria. The observed incidence of postoperative delirium was calculated per risk score per risk stratification instrument. In addition, the risk stratification instruments were compared in terms of area under the receiver operating characteristic (ROC) curve (AUC), and positive and negative predictive value. Finally, the positive agreement between the risk stratification instruments was calculated. When data required for an exact implementation of the original risk stratification instruments was not available, we used alternative data that was comparable. The study population included 292 patients: 60% men; mean age (SD), 66 (8) years; 90% elective surgery. The incidence of postoperative delirium was 9%. The maximum observed incidence per risk score was 50% (95%CI, 15-85%); for eight risk stratification instruments, the maximum observed incidence per risk score was ≤25%. The AUC (95%CI) for the risk stratification instruments varied between 0.50 (0.36-0.64) and 0.66 (0.48-0.83). No AUC was statistically significant from 0.50 (p≥0.11). Positive predictive values of the risk stratification instruments varied between 0-25%, negative predictive values between 89-95%. Positive agreement varied between 0-66%. No risk stratification instrument showed clearly superior performance. In conclusion, in this independent validation cohort, the performance and agreement of commonly used risk stratification instruments for postoperative delirium was poor. Although some caution is needed

  12. Performance trends in master freestyle swimmers aged 25-89 years at the FINA World Championships from 1986 to 2014.

    PubMed

    Knechtle, Beat; Nikolaidis, Pantelis T; König, Stefan; Rosemann, Thomas; Rüst, Christoph A

    2016-02-01

    Performance trends in elite freestyle swimmers are well known, but not for master freestyle swimmers. We investigated trends in participation, performance, and sex difference in performance of 65,584 freestyle master swimmers from 25-29 to 85-89 years competing in FINA World Masters Championships between 1986 and 2014. The men-to-women ratio was calculated for each age group, and the trend across age groups was analyzed using single linear regression analysis. Trends in performance changes were investigated using a mixed-effects regression model with sex, distance, and calendar year as fixed variables. Participation increased in women and men in older age groups (i.e., 40 years and older). Women and men improved race times across years in all age groups and distances. For age groups 25-29 to 75-79 years, women were slower than men, but not for age groups 80-84 to 85-89 years. In 50, 100, and 200 m, women reduced the sex difference from 1986 to 2014 in age groups 30-34 to 75-79 years. In 400 m, women reduced the gap to men across time in age groups 40-44, 45-49, and 55-59 years. In 800 m, sex difference became reduced across time in age groups 55-59 and 70-74 years. In summary, participation increased from 1986 to 2014 in women and men in older age groups, women and men improved across time performance in all distances, and women were not slower compared to men in age groups 80-84 to 85-89 years. We expect a continuous trend in increasing participation and improved performance in master freestyle swimmers.

  13. Effect of castration and slaughter age on performance, carcass, and meat quality traits of Holstein calves fed a high-concentrate diet.

    PubMed

    Marti, S; Realini, C E; Bach, A; Pérez-Juan, M; Devant, M

    2013-03-01

    The aim of this study was to evaluate the effect of castration and slaughter age on performance and meat quality of Holstein bulls fed a high-concentrate diet. A total of 132 animals (116 ± 3.7 kg of BW and 97 ± 2.4 d of age) were randomly allocated in 6 pens using a 3 × 3 factorial arrangement of treatments. Three castration ages [bulls, animals castrated at 3 mo (CAS3), and animals castrated at 8 mo of age (CAS8)] and 3 slaughter ages (10, 12, and 14 mo of age) were evaluated. Feed intake was recorded daily using a computerized concentrate feeder, and BW was recorded every 14 d. The 9th to 11th rib section was removed at 24 h postmortem and dissected into lean, fat, and bone, and meat quality was evaluated on the LM. Castration, at 3 or 8 mo of age, reduced (P < 0.001) ADG and muscle pH and impaired (P < 0.01) feed efficiency. As slaughter age increased, concentrate consumption increased linearly (P < 0.001) and feed efficiency was reduced linearly (P < 0.001). Slaughter age also affected (P < 0.001) meat pH. Significant interactions between castration and slaughter ages were also observed in carcass conformation (P < 0.05), fatness (P < 0.001), percentage of subcutaneous fat (P < 0.01), carcass dressing percentage (P < 0.05), and intramuscular fat (P < 0.05) and tended to be significant in intermuscular fat (P = 0.09). In Holstein animals, castration age affects performance and meat pH regardless of slaughter age, and slaughter age affects performance and meat pH independently of castration. However, in Holstein animals, castration affects several characteristics related to fat deposition differently depending on slaughter age, such as carcass fat cover and intramuscular, intermuscular, and subcutaneous fat.

  14. Performance of an HRP-2 rapid diagnostic test in Nigerian children less than 5 years of age.

    PubMed

    Ajumobi, Olufemi; Sabitu, Kabir; Nguku, Patrick; Kwaga, Jacob; Ntadom, Godwin; Gitta, Sheba; Elizeus, Rutebemberwa; Oyibo, Wellington; Nsubuga, Peter; Maire, Mark; Poggensee, Gabriele

    2015-04-01

    The diagnostic performance of histidine-rich protein 2 (HRP-2)-based malaria rapid diagnostic test (RDT) was evaluated in a mesoendemic area for malaria, Kaduna, Nigeria. We compared RDT results with expert microscopy results of blood samples from 295 febrile children under 5 years. Overall, 11.9% (35/295) tested positive with RDT compared with 10.5% (31/295) by microscopy: sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 100%, 98.5%, 88.6%, and 100%, respectively. The RDT sensitivity was not affected by transmission season, parasite density, and age. Specificity and positive PV decreased slightly during the high-transmission season (97.5% and 83.3%). The RDT test positivity rates in the low- and high-transmission seasons were 9.4% and 13.5%, respectively. Overall, the test performance of this RDT was satisfactory. The findings of a low proportion of RDT false positives, no invalid and no false-negative results should validate the performance of RDTs in this context.

  15. Effects of rhythmic exercise performed to music on the rheological properties of blood in women over 60 years of age.

    PubMed

    Marchewka, Anna; Filar-Mierzwa, Katarzyna; Dąbrowski, Zbigniew; Teległó, Aneta

    2015-01-01

    The aim of this study was to analyze the effects of motor rehabilitation, in the form of rhythmic exercise to music, on the rheological characteristics of blood in older women. The study included 30 women (65-80 years of age), and the control group was comprised of 10 women of corresponding age. Women from the experimental group were subjected to a five-month rehabilitation program, in the form of rhythmic exercise performed to music (three 30-minute sessions per week); women from the control group were not involved in any regular physical activity. Blood samples from all the women were examined for hematological, rheological, and biochemical parameters prior to the study and five months thereafter. The rehabilitation program was reflected by a significant improvement of erythrocyte count and hematocrit. Furthermore, an improvement of erythrocyte deformability was observed by lower shear stress levels, while no significant changes were noted by the higher shear stress values. The rehabilitation resulted in a marked decrease of the aggregation amplitude while no significant changes were observed in aggregation index and total aggregation half-time. Additionally, the training regimen was reflected by a significant increase in the plasma viscosity, while no significant changes in fibrinogen levels were noted.

  16. Age at the onset of senescence in birds and mammals is predicted by early-life performance.

    PubMed

    Péron, Guillaume; Gimenez, Olivier; Charmantier, Anne; Gaillard, Jean-Michel; Crochet, Pierre-André

    2010-09-22

    Life-history theory predicts that traits involved in maturity, reproduction and survival correlate along a fast-slow continuum of life histories. Evolutionary theories and empirical results indicate that senescence-related traits vary along this continuum, with slow species senescing later and at a slower pace than fast species. Because senescence patterns are typically difficult to estimate from studies in the wild, here we propose to predict the associated trait values in the frame of life-history theory. From a comparative analysis based on 81 free-ranging populations of 72 species of birds and mammals, we find that a nonlinear combination of fecundity, age at first reproduction and survival over the immature stage can account for ca two-thirds of the variance in the age at the onset of actuarial senescence. Our life-history model performs better than a model predicting the onset based on generation time, and it only includes life-history traits during early life as explanatory variables, i.e. parameters that are both theoretically expected to shape senescence and are measurable within relatively short studies. We discuss the good-fit of our life-history model to the available data in the light of current evolutionary theories of senescence. We further use it to evaluate whether studies that provided no evidence for senescence lasted long enough to include the onset of senescence.

  17. Performance on tasks of visuospatial memory and ability: A cross-sectional study in 330 adolescents aged 11 to 20.

    PubMed

    Burggraaf, Rudolf; Frens, Maarten A; Hooge, Ignace T C; van der Geest, Jos N

    2017-01-11

    Cognitive functions mature at different points in time between birth and adulthood. Of these functions, visuospatial skills, such as spatial memory and part-to-whole organization, have often been tested in children and adults but have been less frequently evaluated during adolescence. We studied visuospatial memory and ability during this critical developmental period, as well as the correlation between these abilities, in a large group of 330 participants (aged 11 to 20 years, 55% male). To assess visuospatial memory, the participants were asked to memorize and reproduce sequences of random locations within a grid using a computer. Visuospatial ability was tested using a variation of the Design Organization Test (DOT). In this paper-and-pencil test, the participants had one minute to reproduce as many visual patterns as possible using a numerical code. On the memory task, compared with younger participants, older participants correctly reproduced more locations overall and longer sequences of locations, made fewer mistakes and needed less time to reproduce the sequences. In the visuospatial ability task, the number of correctly reproduced patterns increased with age. We show that both visuospatial memory and ability improve significantly throughout adolescence and that performance on both tasks is significantly correlated.

  18. The strong connection between sensory and cognitive performance in old age: not due to sensory acuity reductions operating during cognitive assessment.

    PubMed

    Lindenberger, U; Scherer, H; Baltes, P B

    2001-06-01

    Cognitive aging research has documented a strong increase in the covariation between sensory and cognitive functioning with advancing age. In part, this finding may reflect sensory acuity reductions operating during cognitive assessment. To examine this possibility, the authors administered cognitive tasks used in prior studies (e.g., Lindenberger & Baltes, 1994) to middle-aged adults under age-simulation conditions of reduced visual acuity, auditory acuity, or both. Visual acuity was lowered through partial occlusion filters, and auditory acuity through headphone-shaped noise protectors. Acuity manipulations reduced visual acuity and auditory acuity in the speech range to values reaching or approximating old-age acuity levels, respectively, but did not lower cognitive performance relative to control conditions. Results speak against assessment-related sensory acuity accounts of the age-related increase in the connection between sensory and cognitive functioning and underscore the need to explore alternative explanations, including a focus on general aspects of brain aging.

  19. Effect of supplementation of calf starter with fennel powder on performance, weaning age and fermentation characteristics in Holstein dairy calves.

    PubMed

    Saeedi, S; Dayani, O; Tahmasbi, R; Khezri, A

    2017-02-01

    The objective of this experiment was to investigate the effects on performance, weaning age and rumen fermentation characteristics in Holstein calves when fennel powder was added to their starter diets. Thirty Holstein calves with a mean birth weight 40 kg (SD = 0.5) were allocated randomly to one of the following experimental diets: (i) control (starter diet without fennel powder), (ii) starter diet containing 0.4% of fennel powder and (iii) starter diet containing 0.8% of fennel powder (DM basis). The effect of treatments on mean dry matter intake was significant (p < 0.05) in the post-weaning and total experimental periods. Average daily weight gain before (0.38, 0.49 and 0.47 kg/day) and after (0.6, 1.01 and 0.83 kg/day) weaning and during the entire study (0.45, 0.7 and 0.58 kg/day) was influenced by diets of 1, 2 and 3, respectively (p < 0.05). Maximum daily weight gain and the best feed conversion ratio were achieved with 0.4% fennel powder. Mean weaning age of the calves supplemented with fennel powder was lower (p < 0.05) than that of the control group. Ruminal fluid pH in calves offered starter containing 0.8% fennel powder was lower (p < 0.05) compared to calves fed the other diets. Ammonia nitrogen content increased (p < 0.05) in the third week of feeding fennel powder. The mean concentration of total short-chain fatty acids (SCFA) and propionate molar percentage in the ruminal fluid of the calves fed with the fennel powder were higher (p < 0.05) at 6 weeks and 2 weeks after weaning than control group; however, acetate-to-propionate molar ratio was lower (p < 0.05). The results showed that adding 0.4% fennel powder to the starter increased the propionate molar percentage in the rumen and improved the calf performance, allowing the calves to be weaned at an earlier age.

  20. Sex and age-related differences in performance in a 24-hour ultra-cycling draft-legal event – a cross-sectional data analysis

    PubMed Central

    2014-01-01

    Background The purpose of this study was to examine the sex and age-related differences in performance in a draft-legal ultra-cycling event. Methods Age-related changes in performance across years were investigated in the 24-hour draft-legal cycling event held in Schötz, Switzerland, between 2000 and 2011 using multi-level regression analyses including age, repeated participation and environmental temperatures as co-variables. Results For all finishers, the age of peak cycling performance decreased significantly (β = −0.273, p = 0.036) from 38 ± 10 to 35 ± 6 years in females but remained unchanged (β = −0.035, p = 0.906) at 41.0 ± 10.3 years in males. For the annual fastest females and males, the age of peak cycling performance remained unchanged at 37.3 ± 8.5 and 38.3 ± 5.4 years, respectively. For all female and male finishers, males improved significantly (β = 7.010, p = 0.006) the cycling distance from 497.8 ± 219.6 km to 546.7 ± 205.0 km whereas females (β = −0.085, p = 0.987) showed an unchanged performance of 593.7 ± 132.3 km. The mean cycling distance achieved by the male winners of 960.5 ± 51.9 km was significantly (p < 0.001) greater than the distance covered by the female winners with 769.7 ± 65.7 km but was not different between the sexes (p > 0.05). The sex difference in performance for the annual winners of 19.7 ± 7.8% remained unchanged across years (p > 0.05). The achieved cycling distance decreased in a curvilinear manner with advancing age. There was a significant age effect (F = 28.4, p < 0.0001) for cycling performance where the fastest cyclists were in age group 35–39 years. Conclusion In this 24-h cycling draft-legal event, performance in females remained unchanged while their age of peak cycling performance decreased and performance in males improved while their age of peak cycling performance remained unchanged. The annual fastest females and males were 37.3 ± 8.5 and 38.3 ± 5.4 years old, respectively. The sex

  1. Frequency-effect of playing screen golf on body composition and golf performance in middle-aged men

    PubMed Central

    Jang, Jung-Hoon; Jee, Yong-Seok; Oh, Hye-Won

    2014-01-01

    There are many studies showing that physical training improves body composition including bone mineral density (BMD) in almost all subjects. However, the frequency-dependent effect of playing golf on body composition is still not clearly comprehended. Moreover, the effect of screen golf in relations with exercise-frequency on body composition and golf performance has not been documented. Forty year old men participated and were classified into 4 groups: Control group (n= 10), BMD1 group (n= 10) played screen golf less than 1 day per a week, BMD2–3 group (n= 10) played screen golf 2–3 days per a week, and BMD5 group (n= 10) played screen golf 5 days per week. Dual-energy X-ray absorptiometry (DXA) was performed on 30 male recreational golfers and 10 sedentary individuals. The data gained through DXA were fat mass, lean mass, regional (head, rib, arm, leg, pelvis, spine and trunk) BMD level, and total BMD level summed by regional scores. The club speeds were measured using the Golfzon Vision machine and the handicap points were measured using a simple questionnaire. The present results suggest that the long-frequency of playing screen golf does not improve bone mineral density, lean mass, and handicap point yet improves fat mass and club speed in the middle-aged men. PMID:25426463

  2. Age-related differences in postural control: effects of the complexity of visual manipulation and sensorimotor contribution to postural performance.

    PubMed

    Toledo, Diana R; Barela, José A

    2014-02-01

    Patterns of adaptive changes to the exposure to a sinusoidal visual stimulus can be influenced by stimulus characteristics as well as the integrity of the sensory and motor systems involved in the task. Sensorimotor deficits due to aging might alter postural responses to visual manipulation, especially in more demanding tasks. The purpose of this study was to compare postural control between young and older adults at different levels of complexity and to examine whether possible sensory and/or motor changes account for postural performance differences in older adults. Older and young adults were submitted to the following tests: postural control assessments, i.e., body sway during upright stance and induced by movement of a visual scene (moving room paradigm); sensory assessments, i.e., visual (acuity and contrast sensitivity) and somatosensory (tactile foot sensitivity and detection of passive ankle motion); and motor assessments, i.e., isometric ankle torque and muscular activity latency after stance perturbation. Older adults had worse sensory and motor performance, larger body sway amplitude during stance and stronger coupling between body sway and moving room motion than younger adults. Multiple linear regression analyses indicated that the threshold for the detection of passive ankle motion contributed the most to variances in body sway and this contribution was more striking when visual information was manipulated in a more unpredictable way. The present study suggests that less accurate information about body position is more detrimental to controlling body position, mainly for older adults in more demanding tasks.

  3. Improvement of short-term memory performance in aged beagles by a nutraceutical supplement containing phosphatidylserine, Ginkgo biloba, vitamin E, and pyridoxine

    PubMed Central

    Araujo, Joseph A.; Landsberg, Gary M.; Milgram, Norton W.; Miolo, Alda

    2008-01-01

    Aged dogs demonstrate cognitive decline that is linked to brain aging. The purpose of the present study was to examine if a commercially available nutraceutical supplement that may be neuroprotective and contains phosphatidylserine, Ginkgo biloba, vitamin E, and pyridoxine could improve cognitive function in aged beagles. Nine aged beagles were tested on performance on a delayed-non-matching-to-position task, which is a neuropsychological test of short-term visuospatial memory. All subjects were tested on 5 baseline sessions; then, to assess the supplement, a crossover design was used in which 1 group received the supplement and the other a control substance in the 1st phase, with treatment conditions being reversed in the 2nd phase. Performance accuracy was significantly improved in supplemented dogs compared with control dogs and the effect was long lasting. These findings suggest that the nutraceutical supplement can improve memory in aged dogs. PMID:18481547

  4. A study on the effects of human age, type of computer and noise on operators' performance of a data entry task.

    PubMed

    Khan, Zahid A; Rizvi, Sayed Aliul H

    2010-01-01

    The effects of human age, type of computer, and noise on computer operators' performance of a data entry task were investigated. Twenty male subjects aged 10-55 were assigned into 4 age groups each consisting of 5 persons. They performed the task for 15 min on desktop and laptop computers in a sitting posture under varying levels of noise. The mean number of characters entered per minute (MNCEPM) was statistically analyzed. Operators in the 16-25 age group achieved the highest rate of data entry at each level of noise investigated. Operators performed better on desktop than on laptop computers. Their performance decreased when noise level increased from 82 to 92 dB(A), but it improved at 102 dB(A). The effects of age and noise were statistically significant. However, the effects of the type of computer, the interactions between age and type of computer, age and noise level, and type of computer and noise were not found to be statistically significant.

  5. Early effects of ageing on the mechanical performance of isolated locomotory (EDL) and respiratory (diaphragm) skeletal muscle using the work-loop technique.

    PubMed

    Tallis, Jason; James, Rob S; Little, Alexander G; Cox, Val M; Duncan, Michael J; Seebacher, Frank

    2014-09-15

    Previous isolated muscle studies examining the effects of ageing on contractility have used isometric protocols, which have been shown to have poor relevance to dynamic muscle performance in vivo. The present study uniquely uses the work-loop technique for a more realistic estimation of in vivo muscle function to examine changes in mammalian skeletal muscle mechanical properties with age. Measurements of maximal isometric stress, activation and relaxation time, maximal power output, and sustained power output during repetitive activation and recovery are compared in locomotory extensor digitorum longus (EDL) and core diaphragm muscle isolated from 3-, 10-, 30-, and 50-wk-old female mice to examine the early onset of ageing. A progressive age-related reduction in maximal isometric stress that was of greater magnitude than the decrease in maximal power output occurred in both muscles. Maximal force and power developed earlier in diaphragm than EDL muscle but demonstrated a greater age-related decline. The present study indicates that ability to sustain skeletal muscle power output through repetitive contraction is age- and muscle-dependent, which may help rationalize previously reported equivocal results from examination of the effect of age on muscular endurance. The age-related decline in EDL muscle performance is prevalent without a significant reduction in muscle mass, and biochemical analysis of key marker enzymes suggests that although there is some evidence of a more oxidative fiber type, this is not the primary contributor to the early age-related reduction in muscle contractility.

  6. Cumulative lead exposure is associated with reduced olfactory recognition performance in elderly men: the Normative Aging Study

    PubMed Central

    Grashow, Rachel; Sparrow, David; Hu, Howard; Weisskopf, Marc G.

    2015-01-01

    Introduction Olfactory dysfunction has been identified as an early warning sign for Alzheimer’s disease, Parkinson’s disease, dementia and more. A few occupational and environmental exposures have also been associated with reduced olfactory function, although the effects of long term environmental exposure to lead on olfactory dysfunction have not been explored. Here we performed olfactory recognition testing in elderly men in a community-dwelling cohort and examined the association with cumulative lead exposure, as assessed by lead in tibial and patellar bone. Methods Olfactory recognition was measured in 165 men from the Normative Aging Study (NAS) who had previously taken part in bone lead measurements using K-X-Ray fluorescence (KXRF). Olfactory recognition was measured using the University of Pennsylvania Smell Identification Test (UPSIT). Associations between olfactory recognition, global cognition and cumulative lead exposure were estimated using linear regression, with additional adjustment for age, smoking, and functional polymorphism status for hemochromatosis (HFE), transferrin (TfC2), glutathione-s-transferase Pi1 (GSTP1) and apolipoprotein E (APOE) genotypes. Sensitivity analyses explored olfactory recognition in men with high global cognitive function as measured using the Mini-Mental Status Exam (MMSE). Results The average age of the NAS participants at the time of olfactory recognition testing was 80.3 (standard deviation or SD = 5.7) years. Mean tibia lead was 16.3 (SD = 12.0) μg/g bone, mean patella lead was 22.4 (SD = 14.4) μg/g bone, and mean UPSIT score was 26.9 out of 40 (SD = 7.0). Consistent with previous findings, age at olfaction testing was negatively associated with UPSIT score. Tibia (but not patella) bone lead was negatively associated with olfaction recognition (per 15 μg/g tibia lead: β = −1.57; 95% CI: −2.93, −0.22; p = 0.02) in models adjusted for smoking and age. Additional adjustment for education did not

  7. Executive function performance and change in aging is predicted by apolipoprotein E, intensified by catechol-O-methyltransferase and brain-derived neurotrophic factor, and moderated by age and lifestyle.

    PubMed

    Sapkota, Shraddha; Bäckman, Lars; Dixon, Roger A

    2017-01-03

    Recent studies have reported several genetic, health, and aging interaction effects in predicting cognitive performance and change. We used an accelerated longitudinal design to examine interactions among genetic, lifestyle, and aging for executive function (EF) in non-demented older adults (n = 634; age range = 53-95 years). The polymorphisms were apolipoprotein E (APOE), catechol-O-methyltransferase (COMT), and brain-derived neurotrophic factor (BDNF). We tested (1) independent and additive effects of APOE, COMT, and BDNF and (2) APOE effect modification for COMT + BDNF, on EF performance and 9-year change as separated by age and lifestyle activities. First, APOE ε4+ carriers had poorer EF performance and steeper 9-year decline. Second, APOE ε4+ carriers with (1) BDNF Met/Met genotype and (2) increasing allelic risk in the COMT + BDNF risk panel had poorer EF performance; these effects were moderated by lifestyle activities (composite of everyday social, physical, and cognitive activities). Examining APOE effect modification for COMT + BDNF risk panel effects with other moderating factors may help identify complex neurobiological and genetic underpinnings of polygenic phenotypes such as EF in aging.

  8. Age of peak performance in elite male and female Ironman triathletes competing in Ironman Switzerland, a qualifier for the Ironman world championship, Ironman Hawaii, from 1995 to 2011

    PubMed Central

    Rüst, Christoph Alexander; Knechtle, Beat; Knechtle, Patrizia; Rosemann, Thomas; Lepers, Romuald

    2012-01-01

    Background The age of peak performance in elite endurance athletes has been investigated for elite marathoners, but not for elite Ironman triathletes. The aim of this study was to analyze the age of peak performance in swimming (3.8 km), cycling (180 km), running (42 km), and overall race time for elite female and male Ironman triathletes competing in Ironman Switzerland, a qualifier for the Ironman world championship, known as the Ironman Hawaii. Methods The age of the annual top ten overall swimmers, cyclists, runners, and annual overall finishers for both male and female elite triathletes and their corresponding split and overall race times at the Ironman Switzerland were analyzed between 1995 and 2011. Results The mean age of the elite Ironman triathletes was 33 ± 3 years for men and 34 ± 4 years for women. For women, the age of peak performance was not significantly different between the three disciplines (P > 0.05), while for men, the best swimmers (29 ± 3 years) were significantly (P < 0.05) younger than the best runners (35 ± 5 years). During the study period, the age of peak performance remained unchanged for men at 31 ± 3 years (P > 0.05), but increased for women from 30 ± 4 years in 1995 to 36 ± 5 years in 2011 (P < 0.01). Conclusion Although both women and men improved their overall race times during the 1995–2011 period, the age of peak performance was similar between women and men in the three disciplines and in overall race time. Future studies need to examine the change in age of peak performance across years in the Ironman Hawaii world championship event. PMID:24198600

  9. Influence of age at first lambing on reproductive and productive performance of Lacaune dairy sheep under an intensive management system.

    PubMed

    Hernandez, Fernando; Elvira, Laura; Gonzalez-Martin, Juan-Vicente; Gonzalez-Bulnes, Antonio; Astiz, Susana

    2011-05-01

    The present study investigated the effect of age at first lambing (AFL) on the performance of Lacaune sheep under intensive management conditions. Records from 3088 maiden sheep from one farm, for the period 2005-2010, were classified into four experimental groups: group E (early) ewes with AFL ⩽390 d; group M (middle) with AFL of 391-450 d; group L (late) with AFL of 451-510 d; and group A (aged) with AFL ⩾511 d. The higher the number of lactations, the lower were the yield/lactation and yield/Day in Milk. Ewes from group M up to 450 days old lambed 0.2 times more often and had 0.25 more lactations than the ewes from group L; in addition, the former group lambed 0.5 times more often and had 0.49 more lactations than ewes from group A. Group A had the lowest yield per lifetime; the yield followed the sequence: group E (1032 l) >group M (1051 l) >group L (989 l) > group A (859 l) (P<0.0001). Yield/lactation was affected by AFL during the first three lactations (P<0.05). Group E produced significantly less milk in the first lactation than ewes from groups M, L and A. AFL correlated negatively with the number of lactations in life (r= -0.26; P<0.0001) and with total milk yield (r= -209; P<0.0001). The productive performance between the ewes that reached puberty early (n=404) or late (n=2684) in life were different (P<0.0001) with the early sheep having a lower total milk yield (591 v. 1073 l, P<0.0001). In conclusion, the current study indicates that the optimal AFL for the Lacaune breed under an intensive dairy system is between 390 and 450 d. Ewes with AFL earlier than 390 d or later than 450 d are likely to have a shorter productive life and a lower lifetime milk production.

  10. Is Presurgery and Early Postsurgery Performance Related to Speech and Language Outcomes at 3 Years of Age for Children with Cleft Palate?

    ERIC Educational Resources Information Center

    Chapman, Kathy

    2004-01-01

    This study examined the relationship between presurgery speech measures and speech and language performance at 39 months as well as the relationship between early postsurgery speech measures and speech and language performance at 39 months of age. Fifteen children with cleft lip and palate participated in the study. Spontaneous speech samples were…

  11. Influence of age and cognitive performance on resting-state brain networks of older adults in a population-based cohort.

    PubMed

    Jockwitz, Christiane; Caspers, Svenja; Lux, Silke; Eickhoff, Simon B; Jütten, Kerstin; Lenzen, Stefan; Moebus, Susanne; Pundt, Noreen; Reid, Andrew; Hoffstaedter, Felix; Jöckel, Karl-Heinz; Erbel, Raimund; Cichon, Sven; Nöthen, Markus M; Shah, N Jon; Zilles, Karl; Amunts, Katrin

    2017-04-01

    Aging leads to global changes in brain structure and cognitive performance, with reorganization of functional brain networks. Importantly, these age-related changes show higher inter-individual variability in older subjects. To particularly address this variability is a challenge for studies on lifetime trajectories from early to late adulthood. The present study therefore had a dedicated focus on late adulthood to characterize the functional connectivity in resting-state networks (RSFC) in relation to age and cognitive performance in 711 older adults (55-85 years) from the 1000BRAINS project. The executive, left and right frontoparietal resting-state (RS) networks showed age-related increases in RSFC. However, older adults did not show changes in RSFC in the default mode network (DMN). Furthermore, lower performance in working memory (WM) was associated with higher RSFC in the left frontoparietal RS network. The results suggest age-related compensatory increases in RSFC which might help to maintain cognitive performance. Nevertheless, the negative correlation between RSFC and WM performance hints at limited cognitive reserve capacity in lower performing older adults. Consequently, the current results provide evidence for a functional reorganization of the brain until late adulthood that might additionally explain parts of the variability of cognitive abilities in older adults.

  12. Mortality in active adults age 70-79 years in relation to performance in a long-distance corridor walk.

    PubMed

    Singer, Richard B

    2009-01-01

    The authors conducted the source study to determine if a brisk corridor walk of 400 meters could be used to classify the performance of active older adults and relate this performance to mortality and other outcomes over a 6-year follow-up. The cohort consisted of 3075 adults resident in designated ZIP codes in Pittsburgh, Pa, and Memphis, Tenn, participating in the Health Aging and Body Composition Study. Out of this cohort, 395 subjects were excluded after evaluation revealed abnormal vital signs or ECG findings, recent cardiac symptoms, recent surgery, recent chest pain, shortness of breath or fainting. Another 356 subjects were unable to complete the 400-meter walk. The 2324 subjects who completed the walk were divided into quartiles according to the time in seconds required for completion (the overall time required ranged widely from 201 to 942 seconds). These 3 groups were designated as "excluded," "stopped," and "completed." Outcomes reported for the 3075 subjects in the total cohort included mortality, new cardiovascular disease events, mobility limitation, and mobility disability. Cardiovascular events were reported for the 2234 subjects (73% of the total) who were free of cardiovascular disease at entry. Results in the article were given in tables and figures and included numbers of entrants, exposures, and events, annual event rates and hazard ratios with SDs. Out of the 3075 entrant subjects, 430 died in the 6 years of follow-up (FU). Excess mortality measured as excess death rate (EDR) was much higher in the excluded and stopped groups (about 22 per 1000 per year) compared with an EDR of 6.4 per 1000 in the completed group. The corresponding mortality ratios (MR), designated as a hazard ratio in the article were about 220% and 135%. Results for comparative morbidity are also given in this abstract.

  13. Emotional responses and memory performance of middle-aged CD1 mice in a 3D maze: effects of low infrared light.

    PubMed

    Michalikova, S; Ennaceur, A; van Rensburg, R; Chazot, P L

    2008-05-01

    Non-thermal near infra-red (IR) has been shown to have many beneficial photobiological effects on a range of cell types, including neurons. In the present study, a pretreatment with a daily 6 min exposure to IR1072 for 10 days yielded a number of significant behavioral effects on middle-aged female CD-1 mice (12-months) tested in a 3D-maze. Middle-aged mice show significant deficits in a working memory test and IR treatment reversed this deficit. Interestingly, the IR treated middle-aged group despite making less memory errors than sham middle-aged group spent longer time in different parts of the maze than both the young group (3-months) and sham-middle-aged group (12-months). Young mice appeared more anxious than middle-aged mice in the first sessions of the test. Exposure to IR appeared to have no significant effects upon exploratory activity or anxiety responses. However, it elicited significant effects on working memory, with the IR middle-aged mice being more considerate in their decision making, which results in an overall improved cognitive performance which is comparable to that of young CD-1 mice. The present study describes a novel method for assessing emotional responses and memory performance in a 3D spatial navigation task and demonstrates the validity of our new all-in-one test and its sensitivity to ageing and non-invasive beneficial IR treatment.

  14. Reading and writing performances of children 7-8 years of age with developmental coordination disorder in Taiwan.

    PubMed

    Cheng, Hsiang-Chun; Chen, Jenn-Yeu; Tsai, Chia-Liang; Shen, Miau-Lin; Cherng, Rong-Ju

    2011-01-01

    Developmental coordination disorder (DCD) refers to a delay in motor development that does not have any known medical cause. Studies conducted in English speaking societies have found that children with DCD display a higher co-occurrence rate of learning difficulties (e.g., problems in reading and writing) than typically developing (TD) children. The present study examined the reading and writing performance of school-aged children with DCD and TD children in Taiwan to determine whether reading and writing difficulties also co-occur with DCD in a non-English speaking society. The Chinese Reading Achievement Test and the Basic Reading and Writing Test were administered to 37 children with DCD (7.8 ± 0.6 years) and 93 TD children (8.0 ± 0.7 years). Children with DCD had significantly lower writing composite scores than TD children on the Basic Reading and Writing Test (105.9 ± 20.0 vs. 114.4 ± 19.9). However, there were no significant differences between children with DCD and TD children in their scores on the Chinese Reading Achievement Test and in their reading composite scores on the Basic Reading and Writing Test. These results contrasted interestingly with those obtained from English-speaking children: English-speaking DCD children showed poorer reading and poorer writing than English-speaking TD children. The possibility that the logographic nature of the Chinese script might have protected the DCD children against additional reading difficulty is discussed.

  15. Association between executive function and physical performance in older Korean adults: findings from the Korean Longitudinal Study on Health and Aging (KLoSHA).

    PubMed

    Huh, Yoonseok; Yang, Eun Joo; Lee, Seung Ah; Lim, Jae-Young; Kim, Ki Woong; Paik, Nam-Jong

    2011-01-01

    Reduced executive function and physical performance are common age-related conditions. This study evaluated the associations between executive function and physical performance in a representative sample of older adults. Cross-sectional data were analyzed from a population-based sample of 629 men and women aged 65 or older and living in one typical city in Korea. Specific aspects of executive function were assessed using the trail making test, digit span test, and lexical fluency test to measure set shifting, working memory and cognitive flexibility functions. Physical performance was measured using performance-oriented mobility assessment (POMA) scores and isokinetic muscle strength. Subjects' self-efficacy was also assessed using the activities-specific balance confidence (ABC) scale. Results of the lexical fluency test were associated with POMA scores and muscle strength, independent of age, gender, education, comorbidity, physical activity status, depression, and global cognition, suggesting that reduced cognitive flexibility is associated with reduced physical performance and muscle strength. Self-efficacy was also independently associated with physical performance and muscle strength. Clinicians need to consider the association between executive function and physical performance when working to improve physical functioning in an aged population.

  16. Effects of age on development of digestive organs and performance of chicks fed a corn-soybean meal versus a crystalline amino acid diet.

    PubMed

    Batal, A B; Parsons, C M

    2002-09-01

    Changes in growth performance and physical and morphological development of the digestive organs were examined in chicks fed a crystalline amino acid (AA) diet compared to chicks fed a corn-soybean meal (SBM) diet. Six pens of eight New Hampshire x Columbian male chicks were assigned to one of three dietary regimens: (1) corn-SBM diet from 0 to 21 d of age; (2) cornstarch-crystalline AA diet from 0 to 21 d of age; and (3) corn-SBM diet from 0 to 7 d of age followed by the crystalline AA diet from 8 to 21 d of age. Weight gain was significantly reduced by feeding a crystalline AA diet from 0 to 21 or 8 to 21 d of age. Feeding a crystalline AA diet for the first 7 d of age depressed absolute weight of the small intestine, pancreas, liver, gizzard, and proven-triculus, and continual feeding through 21 d of age further depressed growth of these organs compared with birds fed a corn-SBM diet for 21 d. When expressing organ weight on a relative basis (g/100 g of BW), reductions were observed at 7 d of age due to feeding a crystalline AA diet but not at 21 d of age. Feeding a crystalline AA diet for the first 7 or 21 d of age depressed intestinal villi height and crypt depth. However, chicks fed the crystalline AA diet only from 8 to 21 d of age had further depressed villi height and crypt depth but greater villi width compared with chicks fed the crystalline AA or corn-SBM diet continually from 0 to 21 d of age. These results indicate that the reduced growth of chicks fed a crystalline AA diet is due in part to slower growth and development of the gastrointestinal tract.

  17. Early Life Hormetic Treatments Decrease Irradiation-Induced Oxidative Damage, Increase Longevity, and Enhance Sexual Performance during Old Age in the Caribbean Fruit Fly

    PubMed Central

    López-Martínez, Giancarlo; Hahn, Daniel A.

    2014-01-01

    Early life events can have dramatic consequences on performance later in life. Exposure to stressors at a young age affects development, the rate of aging, risk of disease, and overall lifespan. In spite of this, mild stress exposure early in life can have beneficial effects on performance later in life. These positive effects of mild stress are referred to as physiological conditioning hormesis. In our current study we used anoxia conditioning hormesis as a pretreatment to reduce oxidative stress and improve organismal performance, lifespan, and healthspan of Caribbean fruit flies. We used gamma irradiation to induce mild oxidative damage in a low-dose experiment, and massive oxidative damage in a separate high-dose experiment, in pharate adult fruit flies just prior to adult emergence. Irradiation-induced oxidative stress leads to reduced adult emergence, flight ability, mating performance, and lifespan. We used a hormetic approach, one hour of exposure to anoxia plus irradiation in anoxia, to lower post-irradiation oxidative damage. We have previously shown that this anoxic-conditioning treatment elevates total antioxidant capacity and lowers post-irradiation oxidative damage to lipids and proteins. In this study, conditioned flies had lower mortality rates and longer lifespan compared to those irradiated without hormetic conditioning. As a metric of healthspan, we tracked mating both at a young age (10 d) and old age (30 d). We found that anoxia-conditioned male flies were more competitive at young ages when compared to unconditioned irradiation stressed male flies, and that the positive effects of anoxic conditioning hormesis on mating success were even more pronounced in older males. Our data shows that physiological conditioning hormesis at a young age, not only improves immediate metrics of organismal performance (emergence, flight, mating), but the beneficial effects also carry into old age by reducing late life oxidative damage and improving lifespan and

  18. Declining Physical Performance Associates with Serum FasL, miR-21, and miR-146a in Aging Sprinters

    PubMed Central

    Alen, Markku; Suominen, Harri; Kovanen, Vuokko; Korhonen, Marko T.

    2017-01-01

    Aging is associated with systemic inflammation and cellular apoptosis accelerating physiological dysfunctions. Whether physically active way of life affects these associations is unclear. This study measured the levels of serum inflammatory and apoptotic molecules, their change over 10 years, and their associations with physical performance in sprint-trained male athletes. HsCRP, cell counts, HGB, FasL, miR-21, and miR-146a were measured cross-sectionally (n = 67, 18–90 yrs) and serum FasL, miR-21, and miR-146a and their aging-related associations with physical performance were assessed over a 10-year follow-up (n = 49, 50–90 yrs). The cross-sectional study showed positive age correlations for neutrophils and negative for lymphocytes, red blood cells, HGB, FasL, and miR-146a. During the 10-year follow-up, FasL decreased (P = 0.017) and miR-21 (P < 0.001) and miR-146a (P = 0.005) levels increased. When combining the molecule levels, aging, and physical performance, FasL associated with countermovement jump and bench press (P < 0.001), miR-21 and miR-146a with knee flexion (P = 0.023; P < 0.001), and bench press (P = 0.004; P < 0.001) and miR-146a with sprint performance (P < 0.001). The studied serum molecules changed in an age-dependent manner and were associated with declining physical performance. They have potential as biomarkers of aging-related processes influencing the development of physiological dysfunctions. Further research is needed focusing on the origins and targets of circulating microRNAs to clarify their function in various tissues with aging. PMID:28127562

  19. The computer-based Symbol Digit Modalities Test: establishing age-expected performance in healthy controls and evaluation of pediatric MS patients.

    PubMed

    Bigi, Sandra; Marrie, R A; Till, C; Yeh, E A; Akbar, N; Feinstein, A; Banwell, B L

    2017-04-01

    Decreased information processing speed (IPS) is frequently reported in pediatric multiple sclerosis (MS) patients. The computerized version of the Symbol Digit Modalities Test (c-SDMT) measures IPS over eight consecutive trials per session and additionally captures changes in performance within the session. Here, we establish normative c-SDMT performance and test-retest reliability in healthy children (HC) and explore differences in the overall c-SDMT-performance between HC and MS patients. This cross-sectional study included 478 HC (237 female, 49.5%) divided into five age groups (2 years each), and 27 MS patients (22 female, 81.5%) aged 8-18 years. The average time to complete the c-SDMT increased with age (|r| 0.70, 95% CI -0.74, -0.64). Test-retest reliability was high (ICC = 0.91) in HC. The total time to complete the c-SDMT did not differ between children with MS and sex- and age- matched HC (p = 0.23). However, MS patients were less likely to show faster performance across all the successive eight trials compared to HC (p = 0.0001). Healthy children demonstrate faster IPS with increasing age, as well as during successive trials of the c-SDMT. The inability of pediatric MS patients to maintain the increase in processing speed over successive trials suggests a reduced capacity for procedural learning, possibly resulting from cognitive fatigue.

  20. Age-Related Occipito-Temporal Hypoactivation during Visual Search: Relationships between mN2pc Sources and Performance

    ERIC Educational Resources Information Center

    Lorenzo-Lopez, L.; Gutierrez, R.; Moratti, S.; Maestu, F.; Cadaveira, F.; Amenedo, E.

    2011-01-01

    Recently, an event-related potential (ERP) study (Lorenzo-Lopez et al., 2008) provided evidence that normal aging significantly delays and attenuates the electrophysiological correlate of the allocation of visuospatial attention (N2pc component) during a feature-detection visual search task. To further explore the effects of normal aging on the…

  1. Age Acquisition Norms from Elderly Spanish People: Characteristics and the Prediction of Word Recognition Performance in Alzheimer's Disease

    ERIC Educational Resources Information Center

    Cuetos, Fernando; Samartino, Tamara; Ellis, Andrew W.

    2012-01-01

    Age of acquisition is possibly the single most potent variable affecting lexical access. It is also a variable that determines the retention or loss of words in patients who have suffered brain injury, and in patients with Alzheimer's disease. But the norms of age of acquisition currently available have largely been obtained from university…

  2. Geriatric Assessment-Identified Deficits in Older Cancer Patients With Normal Performance Status

    PubMed Central

    Deal, Allison M.; Nyrop, Kirsten A.; Williams, Grant R.; Pergolotti, Mackenzi; Wood, William A.; Alston, Shani M.; Gordon, Brittaney-Belle E.; Dixon, Samara A.; Moore, Susan G.; Taylor, W. Chris; Messino, Michael; Muss, Hyman B.

    2015-01-01

    Background. We investigated whether a brief geriatric assessment (GA) would identify important patient deficits that could affect treatment tolerance and care outcomes within a sample of older cancer patients rated as functionally normal (80%–100%) on the Karnofsky performance status (KPS) scale. Methods. Cancer patients aged ≥65 years were assessed using a brief GA that included both professionally and patient-scored KPS and measures of comorbidity, polypharmacy, cognition, function, nutrition, and psychosocial status. Data were analyzed using descriptive statistics and multivariable logistic regression. Results. The sample included 984 patients: mean age was 73 years (range: 65–99 years), 74% were female, and 89% were white. GA was conducted before (23%), during (41%), or after (36%) treatment. Overall, 54% had a breast cancer diagnosis (n = 528), and 46% (n = 456) had cancers at other sites. Moreover, 81% of participants (n = 796) had both professionally and self-rated KPS ≥80, defined as functionally normal, and those patients are the focus of analysis. In this subsample, 550 (69%) had at least 1 GA-identified deficit, 222 (28%) had 1 deficit, 140 (18%) had 2 deficits, and 188 (24%) had ≥3 deficits. Specifically, 43% reported taking ≥9 medications daily, 28% had decreased social activity, 25% had ≥4 comorbidities, 23% had ≥1 impairment in instrumental activities of daily living, 18% had a Timed Up and Go time ≥14 seconds, 18% had ≥5% unintentional weight loss, and 12% had a Mental Health Index score ≤76. Conclusion. Within this sample of older cancer patients who were rated as functionally normal by KPS, GA identified important deficits that could affect treatment tolerance and outcomes. PMID:25765876

  3. Age as a risk factor for the disruption of cognitive performance by exposure to the types of radiation encounted on exploratory class missions to other planets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Exposure to the types of radiation encountered in space (particles of high energy and charge [HZE particles]) produces changes in neurocognitive performance similar to those observed in the aged organism. As such, it is possible that there would be an interaction between the effects of exposure to ...

  4. Job Stress, Stress Related to Performance-Based Accreditation, Locus of Control, Age, and Gender As Related to Job Satisfaction and Burnout in Teachers and Principals.

    ERIC Educational Resources Information Center

    Hipps, Elizabeth Smith; Halpin, Glennelle

    The purpose of the study described here was to: (1) determine the amount of variance in burnout and job satisfaction in public school teachers and principals which could be accounted for by stress related to the state's performance-based accreditation standards; (2) examine the relationship between stress related to state standards and the age and…

  5. Differences in cognitive performance, level of dependency and quality of life (QoL), related to age and cognitive status in a sample of Spanish old adults under and over 80 years of age.

    PubMed

    Calero, Dolores; Navarro, Elena

    2011-01-01

    The main objective of this study was to analyze the similarities and differences in cognitive performance, level of dependency, cognitive plasticity and QoL in a sample of young-old adults and old-old adults, bearing in mind both the age-group (under or over 80 years) and the cognitive status of the participants. The study population consisted of 220 people living in sheltered accommodation for elderly people in the South of Spain, with an average age of 80.75 years. Participants were evaluated by means of cognitive performance tests, a QoL questionnaire, a depression scale and a dependency assessment scale. The results indicate that the main differences in the variables analyzed are due to the cognitive status of the sample and not to the fact that the participants are under or over 80 years of age. The findings show that major inter-individual differences in this stage of life depend not only on age but also on cognitive status, which is thus an important factor to take into account when working with this sector of the population.

  6. Age and 'type' of domain specific entry qualifications as predictors of student nurses' performance in biological, social and behavioural sciences in nursing assessments.

    PubMed

    Ofori, R

    2000-05-01

    The present study explored the effects of age and 'type' of entry qualifications in psychology, sociology and biology on student performance in 'the psychological, sociological and biological perspectives in nursing' module assessments, respectively. Data from 222 students undertaking 'the pre-registration diploma in nursing' programme at a university in the north West of England were analysed. The study found no significant differences in performance among those students with GCSE 'O' level, those with access and those without any type of domain specific qualifications. However, student age significantly predicted performance, with such performances found to be highly consistent across the three modules. The 'non-mature' students (aged < 20 years) were identified in the study as being at risk in terms of academic performance whilst the 'very mature' students (aged > 34 years) were found to predict better overall performance. The findings suggest that, paper qualifications such as GCSE O.level, GNVQ or BTEC in psychology, sociology or biology should not be relied upon as predictors of academic performance in their related nursing modules when selecting potential nurses. On the basis of the findings and their probable explanations, it seems possible that the entry gate to nursing can further be widened by giving more credit to the older applicant who has, for example, achieved NVQ at level 2 or 3. However, such flexibility in nurse selection will have to be matched with equal flexibility in the pre-registration diploma in nursing curriculum which at present fails to recognize 'at risk' groups. The findings and the implications for nurse education and recruitment and discussed with support from a growing number of studies investigating student approaches to studying and learning.

  7. The Effects of Comorbidity and Age on RTOG Study Enrollment in Stage III Non-Small Cell Lung Cancer Patients Who Are Eligible for RTOG Studies

    SciTech Connect

    Firat, Selim; Byhardt, Roger W.; Gore, Elizabeth

    2010-12-01

    Purpose: To determine the influence of measured comorbidity in Radiation Therapy Oncology Group (RTOG) combined modality therapy (CMT) study enrollment in Stage III non-small cell lung cancer (NSCLC). Methods and Materials: One hundred and seventy-one patients with a Karnofsky Performance Score {>=}70 and clinical Stage III NSCLC were analyzed retrospectively for comorbidity, RTOG study eligibility, and enrollment at initial consultation. Effect of comorbidity scores (Cumulative Illness Rating Scale) were tested on patient selection for CMT, RTOG enrollment, and overall survival. Results: Comorbidity (Grade 4; p < 0.005) and use of radiation only (p {<=} 0.001) were associated with inferior survival independent of other factors. Patient selection for CMT was affected by age ({>=}70, p < 0.001), comorbidity (severity index [SI]> 2, p = 0.001), and weight loss (>5%, p = 0.001). Thirty-three patients (19%) were enrolled in a CMT RTOG study (Group 1). Forty-nine patients (29%) were eligible but not enrolled (Group 2), and 57 (33%) were ineligible (Group 3). The most common ineligibility reasons were weight loss (67%) and comorbidity in the exclusion criteria of the RTOG studies (63%). Group 1 patients were the youngest (p = 0.02), with the lowest comorbidity scores (p < 0.001) and SI (p < 0.001) compared with Groups 2 and 3. Group 3 patients were the oldest with the most unfavorable comorbidity profile. Comorbidity scores (SI >2; p = 0.006) and age ({>=}70; p = 0.05) were independent factors influencing RTOG study enrollment in patients meeting study eligibility requirements (Groups 1 and 2). Conclusions: Comorbidity scales could be useful in stratification of patients in advanced lung cancer trials and interpretation of results particularly regarding the elderly population.

  8. Performance of School Age Reading Disabled Students on the Phonological Awareness Subtests of the Comprehensive Test of Phonological Processing (CTOPP)

    ERIC Educational Resources Information Center

    Marshall, Dorothy; Christo, Catherine; Davis, John

    2013-01-01

    This study examined the performance of reading disabled children on the two Phonological Awareness Subtests of the Comprehensive Test of Phonological Processing (CTOPP). Participants performed significantly different on these two subtests with a poorer performance on the Elision subtest than Blending Words. In addition, the two subtests were not…

  9. Chronic intake of red wine polyphenols by young rats prevents aging-induced endothelial dysfunction and decline in physical performance: role of NADPH oxidase.

    PubMed

    Dal-Ros, Stéphanie; Zoll, Joffrey; Lang, Anne-Laure; Auger, Cyril; Keller, Nathalie; Bronner, Christian; Geny, Bernard; Schini-Kerth, Valérie B

    2011-01-14

    Aging is associated with oxidative stress-mediated endothelial dysfunction and decline in physical performance, which promote cardiovascular diseases. This study examined whether chronic intake of red wine polyphenols (RWPs), a rich source of natural antioxidants, prevents aging-related impairment of vascular function and physical exercise capacity. Vascular reactivity from 12, 20 and 40 week-old rats was assessed in organ chambers. Rats received from week 16 to 40 either solvent, RWPs or the antioxidant and NADPH oxidase inhibitor, apocynin. Aging was associated with blunted endothelium-dependent relaxations, oxidative stress (dihydroethidine staining), and an upregulation of eNOS, arginase I, NADPH oxidase p22phox and nox1 subunits, and AT1 and AT2 receptors (assessed by immunohistochemistry) in the mesenteric artery. RWPs and apocynin improved the endothelial dysfunction, normalized oxidative stress and the expression of the different proteins. RWPs also improved aging-related decline in physical exercise. Thus, intake of RWPs protects against aging-induced endothelial dysfunction and decline in physical performance. These effects likely involve the ability of RWPs to normalize oxidative stress and the expression of proteins involved in the formation of NO and the angiotensin II pathway.

  10. Blue judogi may bias competitive performance when seeding system is not used: sex, age, and level of competition effects.

    PubMed

    Julio, Ursula F; Miarka, Bianca; Rosa, João P P; Lima, Giscard H O; Takito, Monica Y; Franchini, Emerson

    2015-02-01

    This study evaluated whether the judogi colour (blue or white) could influence a combat outcome (victory or defeat) in 1,233 judo official combats. Sex, age group, and level of competition were also considered in the analysis. Binomial probability tests showed a higher probability of an athlete's winning a combat wearing blue judogi for both sexes, levels of competition (regional and state), and for the athletes of the junior and senior categories. Thus, blue judogi may bias competitive outcome for both sexes in regional and state level competitions and for athletes above junior age.

  11. Sleep spindles and rapid eye movement sleep as predictors of next morning cognitive performance in healthy middle-aged and older participants.

    PubMed

    Lafortune, Marjolaine; Gagnon, Jean-François; Martin, Nicolas; Latreille, Véronique; Dubé, Jonathan; Bouchard, Maude; Bastien, Célyne; Carrier, Julie

    2014-04-01

    Spindles and slow waves are hallmarks of non-rapid eye movement sleep. Both these oscillations are markers of neuronal plasticity, and play a role in memory and cognition. Normal ageing is associated with spindle and slow wave decline and cognitive changes. The present study aimed to assess whether spindle and slow wave characteristics during a baseline night predict cognitive performance in healthy older adults the next morning. Specifically, we examined performance on tasks measuring selective and sustained visual attention, declarative verbal memory, working memory and verbal fluency. Fifty-eight healthy middle-aged and older adults (aged 50-91 years) without sleep disorders underwent baseline polysomnographic sleep recording followed by neuropsychological assessment the next morning. Spindles and slow waves were detected automatically on artefact-free non-rapid eye movement sleep electroencephalogram. All-night stage N2 spindle density (no./min) and mean frequency (Hz) and all-night non-rapid eye movement sleep slow wave density (no./min) and mean slope (μV/s) were analysed. Pearson's correlations were performed between spindles, slow waves, polysomnography and cognitive performance. Higher spindle density predicted better performance on verbal learning, visual attention and verbal fluency, whereas spindle frequency and slow wave density or slope predicted fewer cognitive performance variables. In addition, rapid eye movement sleep duration was associated with better verbal learning potential. These results suggest that spindle density is a marker of cognitive functioning in older adults and may reflect neuroanatomic integrity. Rapid eye movement sleep may be a marker of age-related changes in acetylcholine transmission, which plays a role in new information encoding.

  12. Suppression of the aging-associated decline in physical performance by a combination of resveratrol intake and habitual exercise in senescence-accelerated mice.

    PubMed

    Murase, Takatoshi; Haramizu, Satoshi; Ota, Noriyasu; Hase, Tadashi

    2009-08-01

    The decline in physical performance with increasing age is a crucial problem in our aging society. We examined the effects of resveratrol, a natural polyphenolic compound present in grapes, in combination with habitual exercise on the aging-associated decline in physical performance in senescence-accelerated prone mice (SAMP1). The endurance capacity of SAMP1 mice undergoing an exercise regimen (SAMP1-Ex) decreased over 12 weeks whereas that of SAMP1 mice fed 0.2% (w/w) resveratrol along with exercise (SAMP1-ExRes) remained significantly higher. In the SAMP1-ExRes group, there was a significant increase in oxygen consumption and skeletal muscle mRNA levels of mitochondrial function-related enzymes. These results suggest that the intake of resveratrol, together with habitual exercise, is beneficial for suppressing the aging-related decline in physical performance and that these effects are attributable, at least in part, to improved mitochondrial function in skeletal muscle.

  13. Performance and age of African and non-African runners in half- and full marathons held in Switzerland, 2000–2010

    PubMed Central

    Aschmann, André; Knechtle, Beat; Cribari, Marco; Rüst, Christoph Alexander; Onywera, Vincent; Rosemann, Thomas; Lepers, Romuald

    2013-01-01

    Background Endurance running performance of African (AF) and non-African (NAF) athletes is investigated, with better performances seen for Africans. To date, no study has compared the age of peak performance between AF and NAF runners. The present research is an analysis of the age and running performance of top AF and NAF athletes, using the hypothesis that AF athletes were younger and faster than NAF athletes. Methods Age and performance of male and female AF and NAF athletes in half-marathons and marathons held in Switzerland in 2000–2010 were investigated using single and multilevel hierarchical regression analyses. Results For half-marathons, male NAF runners were older than male AF runners (P = 0.02; NAF, 31.1 years ± 6.4 years versus AF, 26.2 years ± 4.9 years), and their running time was longer (P = 0.02; NAF, 65.3 minutes ± 1.7 minutes versus AF, 64.1 minutes ± 0.9 minutes). In marathons, differences between NAF and AF male runners in age (NAF, 33.0 years ± 4.8 years versus AF, 28.6 years ± 3.8 years; P < 0.01) and running time (NAF, 139.5 minutes ± 5.6 minutes versus AF, 133.3 minutes ± 2.7 minutes; P < 0.01) were more pronounced. There was no difference in age (NAF, 31.0 years ± 7.0 years versus AF, 26.7 years ± 6.0 years; P > 0.05) or running time (NAF, 75.0 minutes ± 3.7 minutes versus AF, 75.6 minutes ± 5.3 minutes; P > 0.05) between NAF and AF female half-marathoners. For marathoners, NAF women were older than AF female runners (P = 0.03; NAF, 31.6 years ± 4.8 years versus AF, 27.8 years ± 5.3 years), but their running times were similar (NAF, 162.4 minutes ± 7.2 minutes versus AF, 163.0 minutes ± 7.0 minutes; P > 0.05). Conclusion In Switzerland, the best AF male half-marathoners and marathoners were younger and faster than the NAF counterpart runners. In contrast to the results seen in men, AF and NAF female runners had similar performances. Future studies need to investigate performance and age of AF and NAF marathoners in the

  14. Effects of calf weaning age and subsequent management systems on growth performance and carcass characteristics of beef steers.

    PubMed

    Moriel, P; Johnson, S E; Vendramini, J M B; McCann, M A; Gerrard, D E; Mercadante, V R G; Hersom, M J; Arthington, J D

    2014-08-01

    Brahman × British crossbred steers (n = 40 and 38 in yr 1 and 2, respectively) were used to evaluate the effects of calf management systems following early weaning (EW) on growth performance, muscle gene expression, and carcass characteristics. On the day of EW (d 0), steers were stratified by BW and age (95 ± 14 kg; 74 ± 14 d) and randomly assigned to a control treatment that was normally weaned (NW) on d 180 (n = 10 steers/yr) or to 1 of 3 EW treatments: 1) EW and limit fed a high-concentrate diet at 3.5% of BW (as-fed basis) in drylot until d 180 (EW180; n = 10 steers/yr), 2) EW and limit fed a high-concentrate diet at 3.5% of BW (as-fed basis) in drylot until d 90 and then grazed on bahiagrass pastures until d 180 (EW90; n = 10 steers/yr), or 3) EW and grazed on annual ryegrass pastures until d 60 (yr 1; n = 10 steers) or 90 (yr 2; n = 8 steers) and then on bahiagrass pastures until d 180 (EWRG). Early-weaned steers on ryegrass and bahiagrass pastures were supplemented with high-concentrate diet at 1.0% of BW (as-fed basis) until d 180. From d 180 to 270 (yr 1), all EW steers remained in their respective treatments, whereas NW steers were provided high-concentrate diet at 1.0% of BW (as-fed basis) on bahiagrass pastures. In yr 1, feedlot finishing period began on d 270. In yr 2, the study was terminated on d 180. In both years, EW180 steers were heaviest (P < 0.0001) on d 180. On d 180 of yr 1, EWRG steers were lightest (P < 0.0001) and EW90 steers were heavier (P = 0.05) than NW steers, whereas EW90, EWRG, and NW steers had similar BW on d 180 of yr 2 (P ≥ 0.14). On d 90, muscle PPARγ mRNA expression tended (P = 0.07) to be greater for EW180 steers and was greater (P = 0.008) for EW90 vs. EWRG steers but similar (P = 0.25) between EW180 and NW steers. On d 180, PPARγ mRNA was greater (P ≤ 0.06) for EW180 vs. NW, EW90, and EWRG steers. From d 274 to 302, EW180 steers had the least ADG (P ≤ 0.09), whereas EW90 steers had similar (P = 0.19) ADG

  15. Associations between Tactile Sensory Threshold and Postural Performance and Effects of Healthy Aging and Subthreshold Vibrotactile Stimulation on Postural Outcomes in a Simple Dual Task

    PubMed Central

    Dettmer, Marius; Pourmoghaddam, Amir; Lee, Beom-Chan; Layne, Charles S.

    2016-01-01

    Specific activities that require concurrent processing of postural and cognitive tasks may increase the risk for falls in older adults. We investigated whether peripheral receptor sensitivity was associated with postural performance in a dual-task and whether an intervention in form of subthreshold vibration could affect performance. Ten younger (age: 20–35 years) and ten older adults (70–85 years) performed repeated auditory-verbal 1-back tasks while standing quietly on a force platform. Foot sole vibration was randomly added during several trials. Several postural control and performance measures were assessed and statistically analyzed (significance set to α-levels of .05). There were moderate correlations between peripheral sensitivity and several postural performance and control measures (r = .45 to .59). Several postural performance measures differed significantly between older and younger adults (p < 0.05); addition of vibration did not affect outcome measures. Aging affects healthy older adults' performance in dual-tasks, and peripheral sensitivity may be a contributor to the observed differences. A vibration intervention may only be useful when there are more severe impairments of the sensorimotor system. Hence, future research regarding the efficacy of sensorimotor interventions in the form of vibrotactile stimulation should focus on older adults whose balance is significantly affected. PMID:27143967

  16. Performance trends in age-group runners from 100 m to marathon-The World Championships from 1975 to 2015.

    PubMed

    Nikolaidis, P T; Zingg, M A; Knechtle, B

    2017-01-30

    This study examined changes in performance in age-group track runners across years from 1975 to 2015 for 100, 200, 400, 800, 1500, 5000, 10 000 m, and marathon and the corresponding sex differences. Athletes were ranked in 5-year age-group intervals from 35-39 to 95-99 years. For all races and all years, the eight female and male finalists for each age-group were included. Men were faster than women and this observation was more pronounced in the shorter distances. The younger age-groups were faster than the older age-groups and age exerted the largest effect on speed in 800 m and the smallest in marathon. There was a small variation of speed by calendar years. The competition density varied by sex and race distance. Half of participants were from USA, Germany, Australia, and Great Britain, but the participants' nationality varied by sex and race distance. In summary, the variation of competitiveness by sex in short race distances might be important for athletes and coaches. Considering the event's competitiveness and that athletes are participating in both 100 and 200 m or in 200 and 400 m, master women should be oriented to 200 m and master men should be oriented to 100 and 400 m.

  17. Salivary Cortisol, Socioemotional Functioning, and Academic Performance in Anxious and Non-Anxious Children of Elementary and Middle School Age

    ERIC Educational Resources Information Center

    Mathewson, Karen J.; Miskovic, Vladimir; Cunningham, Charles E.; McHolm, Angela E.; Boyle, Michael H.; Schmidt, Louis A.

    2012-01-01

    Research Findings: Individual and contextual variables were examined in relation to children's ability to cope with socioemotional and academic challenges in a sample of typically developing (n = 51) and anxious (n = 72) children of elementary and middle school age. Anxious children had greater social difficulties than controls and showed…

  18. Neuropsychological Testing in a Rural African School-Age Population: Evaluating Contributions to Variability in Test Performance

    ERIC Educational Resources Information Center

    Kitsao-Wekulo, Patricia K.; Holding, Penny A.; Taylor, H. Gerry; Abubakar, Amina; Connolly, Kevin

    2013-01-01

    This study investigated the psychometric properties of a number of neuropsychological tests adapted for use in sub-Saharan Africa. A total of 308 school-age children in a predominantly rural community completed the tests. These tests were developed to assess skills similar to those measured by assessments of cognitive development published for use…

  19. Is there a relationship between the performance in a chronometric mental-rotations test and salivary testosterone and estradiol levels in children aged 9-14 years?

    PubMed

    Quaiser-Pohl, Claudia; Jansen, Petra; Lehmann, Jennifer; Kudielka, Brigitte M

    2016-01-01

    The consistent gender differences favoring males in some spatial abilities like mental rotation have raised the question of whether testosterone or other gonadal hormones contribute to these differences--especially because such gender differences seem to appear mainly from the age of puberty on. Studies generally suggest that spatial ability is facilitated by moderately high testosterone levels (i.e., levels that are relatively high for females and relatively low for males). However, the role of sex steroids for mental-rotation performance of (pre-) pubertal children has not been the focus of research, yet. In our study, the relationships between different aspects of mental-rotation performance (accuracy, reaction time, rotation speed) and salivary testosterone and estradiol levels were investigated. Subjects were 109 children (51 boys and 58 girls) aged between 9 and 14 years (M = 11.41, SD = 1.74). They performed a chronometric mental-rotations test, in which the stimuli consisted of three-dimensional drawings of Shepard and Metzler cube figures. In addition, saliva samples were gathered for the analysis of free testosterone and estradiol levels. Results showed a significant gender difference in reaction time and rotational speed in favor of boys, and a significant age, but no gender difference in testosterone and estradiol levels. We found no significant relationships between hormonal levels and any measure of mental-rotation performance.

  20. Efficient immobilization of AGE and NAL enzymes onto functional amino resin as recyclable and high-performance biocatalyst.

    PubMed

    Cheng, Jian; Zhuang, Wei; Tang, Chenglun; Chen, Yong; Wu, Jinglan; Guo, Ting; Ying, Hanjie

    2017-03-01

    N-Acetylglucosamine-2-epimerase (AGE) and N-acetylneuraminic acid lyase (NAL) were immobilized for synthesis of N-acetylneuraminic acid (Neu5Ac) on three resins: Amberzyme oxirane resin (AOR), poly (styrene-co-DVB)-Br resin (PBR) and amino resin (AR). The loading capacity and immobilized enzyme activity showed that AR was the best carrier. Three methods of glutaraldehyde cross-linking were tested and simultaneous cross-linking and immobilization was demonstrated to be the best method. The functional properties of immobilized AGE and NAL were studied and compared to those of the free enzyme. The highest enzyme activities of free and immobilized AGE were obtained in 0.1 M potassium phosphate buffer at pH 7.5 and a temperature of 37 °C. Comparatively, the highest NAL activities were at pH 8.5. Meanwhile, an increase in K m (from 1.14 to 1.31 mg·mL(-1) for AGE and from 1.05 to 1.25 mg·mL(-1) for NAL) and a decrease in V max (from 177.53 to 106.37 µg·min(-1) mL(-1) for AGE and from 126.41 to 95.96 µg·min(-1) mL(-1) for NAL) were recorded after immobilization. The AR-glutaraldehyde-enzyme system exhibited better thermal stability than the free enzyme, and retained 72% of its initial activity even after eight repeated runs. The apparent activation energy (E a) of the free and immobilized AGE (NAL) was 117.14 kJ·mol(-1) (124.21 kJ·mol(-1)) and 78.45 kJ·mol(-1) (66.64 kJ·mol(-1)), respectively, implying that the catalytic efficiency of the immobilized enzyme was restricted by mass-transfer rather than kinetic limit. Subsequently, Neu5Ac production from GlcNAc using immobilized enzymes in one reactor was carried out resulting 101.45 g·L(-1) of Neu5Ac and the highest conversion ratio of 82%. This method of enzyme immobilization may have a promising future for Neu5Ac production in industry.

  1. Teachers' Reporting of Behavioural Problems and Cognitive-Academic Performances in Children Aged 5-7 Years

    ERIC Educational Resources Information Center

    Giannopulu, I.; Escolano, S.; Cusin, F.; Citeau, H.; Dellatolas, G.

    2008-01-01

    Background: The behavioural and academic performance of young children with teachers' reported hyperactivity, conduct problems or inattention is under debate. Aim: This study investigates the associations between teachers' reported behavioural difficulties and academic and cognitive performances in two large samples of preschool and school…

  2. Age associated declines in muscle mass, strength, power, and physical performance: impact on fear of falling and quality of life

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SUMMARY: This 3 year longitudinal study among older adults showed that declining muscle mass, strength, power, and physical performance are independent contributing factors to increased fear of falling, while declines of muscle mass and physical performance contribute to deterioration of quality of ...

  3. Age-Related Changes in Brain Activation Underlying Single- and Dual-Task Performance: Visuomanual Drawing and Mental Arithmetic

    ERIC Educational Resources Information Center

    Van Impe, A.; Coxon, J. P.; Goble, D. J.; Wenderoth, N.; Swinnen, S. P.

    2011-01-01

    Depending on task combination, dual-tasking can either be performed successfully or can lead to performance decrements in one or both tasks. Interference is believed to be caused by limitations in central processing, i.e. structural interference between the neural activation patterns associated with each task. In the present study, single- and…

  4. The Patient's Age and American Society of Anesthesiologists Status Are Reasonable Criteria for Deciding Whether to Perform Same-Day Bilateral TKA.

    PubMed

    Koh, In Jun; Kim, Geon-Hyeong; Kong, Chae-Gwan; Park, Se-Wook; Park, Tae Yong; In, Yong

    2015-05-01

    We investigated whether basing a decision to perform same-day bilateral TKA (SD BTKA) on the patient's age and American Society of Anesthesiologists (ASA) status was reasonable. We retrospectively reviewed the records of 1386 patients who underwent 2086 TKAs (686 unilateral TKAs [UTKAs], 1038 SD BTKAs, and 362 one-week staged BTKAs). For the entire cohort, patients undergoing SD BTKA had a higher risk of major complications compared to those undergoing UTKA. However, there was no difference in the incidence of complications for patients aged<75 years with an ASA status of 1 or 2 who underwent UTKA or SD BTKA. If patients are selected based on age and ASA status, SD BTKA may have a risk of postoperative complication similar to UTKA.

  5. Vascular function, cerebral cortical thickness, and cognitive performance in middle-aged Hispanic and non-Hispanic Caucasian adults.

    PubMed

    Pasha, Evan P; Kaur, Sonya S; Gonzales, Mitzi M; Machin, Daniel R; Kasischke, Kennon; Tanaka, Hirofumi; Haley, Andreana P

    2015-04-01

    Hispanics are at increased risk for acquiring cardiovascular risk factors that contribute to cognitive dysfunction. To compare indices of vascular health with measures of cerebral gray matter integrity, 60 middle-aged Hispanic and non-Hispanic Caucasian participants were matched across age, sex, years of education, and mental status. Arterial stiffness was characterized by β-stiffness index and carotid-femoral pulse wave velocity, and magnetic resonance imaging estimated cortical thickness in a priori regions of interest known to be susceptible to vascular risk factors. Measures of arterial stiffness were significantly higher in Hispanics than in non-Hispanic Caucasians. Hispanics exhibited thinner left inferior frontal gyrus (LIFG) cortical thickness (P=.04) with concurrently lower language (P=.02), memory (P=.03), and attention-executive functioning (P=.02). These results suggest that compromised vascular health may occur simultaneously with cortical thinning of the LIFG as an early neuropathological alteration in Hispanics.

  6. Inclusion of fiber in diets for brown-egg laying pullets: Effects on growth performance and digestive tract traits from hatching to 17 weeks of age.

    PubMed

    Guzmán, P; Saldaña, B; Kimiaeitalab, M V; García, J; Mateos, G G

    2015-11-01

    We investigated the effects of fiber inclusion in the diet on growth performance and digestive traits in pullets from hatching to 17 wk of age. The control diets of the 3 feeding periods (0 to 5 wk, 5 to 10 wk, and 10 to 17 wk) were based on corn and soybean meal and did not include any additional fiber source. The experimental diets included 2 or 4% of cereal straw or sugar beet pulp (SBP) at the expense (wt:wt) of the control diet. From 0 to 5 wk of age, fiber inclusion did not affect pullet performance. From hatch to 17 wk of age, the inclusion of straw had little effect on pullet performance but the inclusion of 4% SBP reduced (ADG) (P < 0.05) and reduced feed conversion ratio (FCR; P < 0.001). Pullets fed straw had greater ADG (P < 0.05) and better energy conversion ratio (P < 0.01) than pullets fed SBP. An increase in fiber from 2 to 4% reduced FCR (P < 0.05). Body weight uniformity was not affected by diet. Fiber inclusion increased the relative weight (% BW) of the gizzard at 5 wk (P = 0.056) and 10 wk (P < 0.01) of age, but no differences were detected between fiber sources. At same ages, the relative length (cm/kg BW) of the pullets (P = 0.058 and P < 0.01, respectively) and tarsus (P = 0.079 and P < 0.05, respectively) was higher in pullets fed SBP than in pullets fed straw. Fiber inclusion, however, did not affect any of these traits at 17 wk of age. In summary, the inclusion of 2% straw at the expense (wt:wt) of the whole diet did not affect pullet performance at 17 wk of age. An increase in the level of straw from 2 to 4% reduced FCR but did not affect ADG. The inclusion of SBP, however, reduced pullet growth, with effects being more pronounced at the higher level.

  7. Stunting syndrome in broilers: effect of age and exogenous amylase and protease on performance, development of the digestive tract, digestive enzyme activity, and apparent digestibility.

    PubMed

    Shapiro, F; Nir, I

    1995-12-01

    Day-old male, meat-type chicks raised in brooder batteries were infected by orally administering an inoculum prepared from intestines of broiler chicks infected with stunting syndrome (SS). Naive controls were kept in a parallel room. The chicks were fed a commercial starter diet supplemented with two levels of enzyme preparations to 14 d of age. The experiment was continued to the age of 6 wk in order to estimate compensatory feed intake and growth. In a parallel study, digestibility of the feed was determined from 1 to 3 wk of age with control or inoculated chicks. The enzymes amylase and proteases were produced by Bacillus subtilis and Penicillium emersonii. Enzyme supplementation had no effect on feed intake, growth, or feed utilization, or on digestibility of fat, starch, protein, or energy. Because enzyme supplementation did not consistently affect performance of chicks and no interactions were observed between enzyme supplementation and infection status, data are presented for effects of infection only. Inoculation of SS-infective material reduced performance to 4 wk. Compensatory growth and feed intake were observed from the age of 4 wk onward. At the age of 6 wk the slight retardation of the inoculated chicks was not significant. On Week 1, retention of fat, starch, protein, and energy was significantly depressed in the inoculated chicks. At the age of 2 wk, retention of starch was not depressed, and at the age of 3 wk, the only consistent depression was that observed for fat. The proventriculus weight and content were consistently higher in inoculated chicks, as were the small intestine and intestinal content. The pH of the gizzard content was higher, and that of the small intestine content was lower, in the inoculated birds than in their control counterparts. Stunting syndrome infection was accompanied by a significant depression of trypsin activity in the pancreas at the age of 1 and 2 wk. At these periods, amylase and chymotrypsin were not affected. At

  8. The Effects of a Positive Mindset Trigger Word Pre-Performance Routine on the Expressive Performance of Junior High Age Singers

    ERIC Educational Resources Information Center

    Broomhead, Paul; Skidmore, Jon B.; Eggett, Dennis L.; Mills, Melissa M.

    2012-01-01

    The effects of a positive mindset trigger word intervention on the expressive performance of individual junior high singers were tested in this study. Participants (N = 155) were assigned randomly to a control group or an experimental group. Members of the experimental group participated in a 40-min intervention while members of the control group…

  9. Age-Related Differences and Cognitive Correlates of Self-Reported and Direct Navigation Performance: The Effect of Real and Virtual Test Conditions Manipulation.

    PubMed

    Taillade, Mathieu; N'Kaoua, Bernard; Sauzéon, Hélène

    2015-01-01

    The present study investigated the effect of aging on direct navigation measures and self-reported ones according to the real-virtual test manipulation. Navigation (wayfinding tasks) and spatial memory (paper-pencil tasks) performances, obtained either in real-world or in virtual-laboratory test conditions, were compared between young (n = 32) and older (n = 32) adults who had self-rated their everyday navigation behavior (SBSOD scale). Real age-related differences were observed in navigation tasks as well as in paper-pencil tasks, which investigated spatial learning relative to the distinction between survey-route knowledge. The manipulation of test conditions (real vs. virtual) did not change these age-related differences, which are mostly explained by age-related decline in both spatial abilities and executive functioning (measured with neuropsychological tests). In contrast, elderly adults did not differ from young adults in their self-reporting relative to everyday navigation, suggesting some underestimation of navigation difficulties by elderly adults. Also, spatial abilities in young participants had a mediating effect on the relations between actual and self-reported navigation performance, but not for older participants. So, it is assumed that the older adults carried out the navigation task with fewer available spatial abilities compared to young adults, resulting in inaccurate self-estimates.

  10. Age-Related Differences and Cognitive Correlates of Self-Reported and Direct Navigation Performance: The Effect of Real and Virtual Test Conditions Manipulation

    PubMed Central

    Taillade, Mathieu; N'Kaoua, Bernard; Sauzéon, Hélène

    2016-01-01

    The present study investigated the effect of aging on direct navigation measures and self-reported ones according to the real-virtual test manipulation. Navigation (wayfinding tasks) and spatial memory (paper-pencil tasks) performances, obtained either in real-world or in virtual-laboratory test conditions, were compared between young (n = 32) and older (n = 32) adults who had self-rated their everyday navigation behavior (SBSOD scale). Real age-related differences were observed in navigation tasks as well as in paper-pencil tasks, which investigated spatial learning relative to the distinction between survey-route knowledge. The manipulation of test conditions (real vs. virtual) did not change these age-related differences, which are mostly explained by age-related decline in both spatial abilities and executive functioning (measured with neuropsychological tests). In contrast, elderly adults did not differ from young adults in their self-reporting relative to everyday navigation, suggesting some underestimation of navigation difficulties by elderly adults. Also, spatial abilities in young participants had a mediating effect on the relations between actual and self-reported navigation performance, but not for older participants. So, it is assumed that the older adults carried out the navigation task with fewer available spatial abilities compared to young adults, resulting in inaccurate self-estimates. PMID:26834666

  11. Does Consumption of LC Omega-3 PUFA Enhance Cognitive Performance in Healthy School-Aged Children and throughout Adulthood? Evidence from Clinical Trials

    PubMed Central

    Stonehouse, Welma

    2014-01-01

    Long-chain (LC) omega-3 PUFA derived from marine sources may play an important role in cognitive performance throughout all life stages. Docosahexaenoic acid (DHA), the dominant omega-3 in the brain, is a major component of neuronal cell membranes and affects various neurological pathways and processess. Despite its critical role in brain function, human’s capacity to synthesize DHA de novo is limited and its consumption through the diet is important. However, many individuals do not or rarely consume seafood. The aim of this review is to critically evaluate the current evidence from randomised controlled trials (RCT) in healthy school-aged children, younger and older adults to determine whether consumption of LC omega-3 PUFA improves cognitive performance and to make recommendations for future research. Current evidence suggests that consumption of LC omega-3 PUFA, particularly DHA, may enhance cognitive performance relating to learning, cognitive development, memory and speed of performing cognitive tasks. Those who habitually consume diets low in DHA, children with low literacy ability and malnourished and older adults with age-related cognitive decline and mild cognitive impairment seem to benefit most. However, study design limitations in many RCTs hamper firm conclusions. The measurement of a uniform biomarker, e.g., % DHA in red blood cells, is essential to establish baseline DHA-status, to determine targets for cognitive performance and to facilitate dosage recommendations. It is recommended that future studies be at least 16 weeks in duration, account for potential interaction effects of gender, age and apolipoprotein E genotype, include vegan/vegetarian populations, include measures of speed of cognitive performance and include brain imaging technologies as supportive information on working mechanisms of LC omega-3 PUFA. PMID:25054550

  12. Does consumption of LC omega-3 PUFA enhance cognitive performance in healthy school-aged children and throughout adulthood? Evidence from clinical trials.

    PubMed

    Stonehouse, Welma

    2014-07-22

    Long-chain (LC) omega-3 PUFA derived from marine sources may play an important role in cognitive performance throughout all life stages. Docosahexaenoic acid (DHA), the dominant omega-3 in the brain, is a major component of neuronal cell membranes and affects various neurological pathways and processess. Despite its critical role in brain function, human's capacity to synthesize DHA de novo is limited and its consumption through the diet is important. However, many individuals do not or rarely consume seafood. The aim of this review is to critically evaluate the current evidence from randomised controlled trials (RCT) in healthy school-aged children, younger and older adults to determine whether consumption of LC omega-3 PUFA improves cognitive performance and to make recommendations for future research. Current evidence suggests that consumption of LC omega-3 PUFA, particularly DHA, may enhance cognitive performance relating to learning, cognitive development, memory and speed of performing cognitive tasks. Those who habitually consume diets low in DHA, children with low literacy ability and malnourished and older adults with age-related cognitive decline and mild cognitive impairment seem to benefit most. However, study design limitations in many RCTs hamper firm conclusions. The measurement of a uniform biomarker, e.g., % DHA in red blood cells, is essential to establish baseline DHA-status, to determine targets for cognitive performance and to facilitate dosage recommendations. It is recommended that future studies be at least 16 weeks in duration, account for potential interaction effects of gender, age and apolipoprotein E genotype, include vegan/vegetarian populations, include measures of speed of cognitive performance and include brain imaging technologies as supportive information on working mechanisms of LC omega-3 PUFA.

  13. Development of an active wheat gluten film with Lactobacillus curvatus CRL705 bacteriocins and a study of its antimicrobial performance during ageing.

    PubMed

    Blanco Massani, Mariana; Botana, Adrián; Eisenberg, Patricia; Vignolo, Graciela

    2014-01-01

    Antimicrobial wheat gluten film was obtained at pilot scale by Lactobacillus curvatus CRL705 bacteriocins inclusion in the film-forming solution. Bacteriocins' minimum inhibitory concentration for the film activation was 2133 AU cm(-3) (lactocin AL705) and 267 AU cm(-3) (lactocin 705). Mechanical and barrier properties as well as film ageing kinetics were not significantly affected by the addition of bacteriocins. The antimicrobial film performance during ageing was assessed. Film activity against Listeria innocua 7 and Lactobacillus plantarum CRL691 was observed over 50 days of ageing. Even when the release of bacteriocins from the film upon water contact was observed for both bacteriocins at the beginning of the ageing period, and anti-Listeria activity was delivered to the simulant up to the 15th day of ageing, film residual activity for both bacteriocins was observed over 50 days. The results confirm the potential of a gluten film doped with L. curvatus CRL705 bacteriocins as a carrier of bacteriocins to avoid Listeria and lactic acid bacterial growth, thus enhancing quality and safety in foods.

  14. Age of acquisition predicts naming and lexical-decision performance above and beyond 22 other predictor variables: an analysis of 2,342 words.

    PubMed

    Cortese, Michael J; Khanna, Maya M

    2007-08-01

    Age of acquisition (AoA) ratings were obtained and were used in hierarchical regression analyses to predict naming and lexical-decision performance for 2,342 words (from Balota, Cortese, Sergent-Marshall, Spieler, & Yap, 2004). In the analyses, AoA was included in addition to the set of predictors used by Balota et al. (2004). AoA significantly predicted latency performance on both tasks above and beyond the standard predictor set. However, AoA was more strongly related to lexical-decision performance than to naming performance. Finally, the previously reported effect of imageability on naming latencies by Balota et al. was not significant with AoA included as a factor. These results are consistent with the idea either that AoA has a semantic/lexical locus or that AoA effects emerge primarily in situations in which the input-output mapping is arbitrary.

  15. An Analysis of Field-Aged Diesel Particulate Filter Performance: Particle Emissions Before, During and After Regeneration

    SciTech Connect

    Barone, Teresa L; Storey, John Morse; Domingo, Norberto

    2010-01-01

    A field-aged, passive diesel particulate filter (DPF) employed in a school bus retrofit program was evaluated for emissions of particle mass and number concentration before, during and after regeneration. For the particle mass measurements, filter samples were collected for gravimetric analysis with a partial flow sampling system, which sampled proportionally to the exhaust flow. Total number concentration and number-size distributions were measured by a condensation particle counter and scanning mobility particle sizer, respectively. The results of the evaluation show that the number concentration emissions decreased as the DPF became loaded with soot. However after soot removal by regeneration, the number concentration emissions were approximately 20 times greater, which suggests the importance of the soot layer in helping to trap particles. Contrary to the number concentration results, particle mass emissions decreased from 6 1 mg/hp-hr before regeneration to 3 2 mg/hp-hr after regeneration. This indicates that nanoparticles with diameter less than 50 nm may have been emitted after regeneration since these particles contribute little to the total mass. Overall, average particle emission reductions of 95% by mass and 10,000-fold by number concentration after four years of use provided evidence of the durability of a field-aged DPF. In contrast to previous reports for new DPFs in which elevated number concentrations occurred during the first 200 seconds of a transient cycle, the number concentration emissions were elevated during the second half of the heavy-duty federal test procedure when high speed was sustained. This information is relevant for the analysis of mechanisms by which particles are emitted from field-aged DPFs.

  16. An analysis of field-aged diesel particulate filter performance: particle emissions before, during, and after regeneration.

    PubMed

    Barone, Teresa L; Storey, John M E; Domingo, Norberto

    2010-08-01

    A field-aged, passive diesel particulate filter (DPF) used in a school bus retrofit program was evaluated for emissions of particle mass and number concentration before, during, and after regeneration. For the particle mass measurements, filter samples were collected for gravimetric analysis with a partial flow sampling system, which sampled proportionally to the exhaust flow. A condensation particle counter and scanning mobility particle sizer measured total number concentration and number-size distributions, respectively. The results of the evaluation show that the number concentration emissions decreased as the DPF became loaded with soot. However, after soot removal by regeneration, the number concentration emissions were approximately 20 times greater, which suggests the importance of the soot layer in helping to trap particles. Contrary to the number concentration results, particle mass emissions decreased from 6 +/- 1 mg/hp-hr before regeneration to 3 +/- 2 mg/hp-hr after regeneration. This indicates that nanoparticles with diameters less than 50 nm may have been emitted after regeneration because these particles contribute little to the total mass. Overall, average particle emission reductions of 95% by mass and 10,000-fold by number concentration after 4 yr of use provided evidence of the durability of a field-aged DPF. In contrast to previous reports for new DPFs in which elevated number concentrations occurred during the first 200 sec of a transient cycle, the number concentration emissions were elevated during the second half of the heavy-duty Federal Test Procedure (FTP) when high speed was sustained. This information is relevant for the analysis of mechanisms by which particles are emitted from field-aged DPFs.

  17. Solvent dependence of laser-synthesized blue-emitting Si nanoparticles: Size, quantum yield, and aging performance

    NASA Astrophysics Data System (ADS)

    Xin, Yunzi; Kitasako, Takumi; Maeda, Makoto; Saitow, Ken-ichi

    2017-04-01

    Pulsed-laser ablation of silicon (Si) was conducted in six different organic solvents using a nanosecond laser. Si nanoparticles (Si-NPs) that exhibited blue photoluminescence (PL) were generated in all the solvents, but a significant solvent dependence emerged: particle size, PL spectra, and PL quantum yield (QY). The results of solvent dependence were well characterized using an atomic ratio in a solvent molecule. The highest QY was observed for the smallest Si-NPs (ca. 2 nm) synthesized in 1-octyne. The QY was enhanced by aging in 1-octyne, and its mechanism was attributed to alkyl passivation of dangling bonds on the Si-NPs.

  18. Influence of feed form and source of soybean meal of the diet on growth performance of broilers from 1 to 42 days of age. 1. Floor pen study.

    PubMed

    Serrano, M P; Valencia, D G; Méndez, J; Mateos, G G

    2012-11-01

    In total, 3,120 broilers were used to study the effects of feed form and source of soybean meal (SBM) of the diet on growth performance. From 1 to 21 d of age, there were 12 treatments arranged factorially with 3 feed forms (mash, crumbles, and pellets) and 4 commercial sources of SBM that differed in the CP content [48.1 and 46.2% CP from the United States (USA-1 and USA-2), 47.6% CP from Brazil (BRA), and 46.3% CP from Argentina (ARG)]. From 21 to 42 d of age, diets were fed as pellets. Diets were formulated assuming that all SBM had similar digestible amino acid content per unit of CP. From 1 to 21 d of age, chicks fed crumbles or pellets had higher (P < 0.001) ADG than chicks fed mash. Also, chicks fed pellets had better (P < 0.001) feed-to-gain ratio (F:G) than chicks fed crumbles, and both were better than chicks fed mash. However, from 21 to 42 d of age, F:G was best (P < 0.001) for chicks previously fed mash. For the entire experimental period, broilers that were fed crumbles or pellets from 1 to 21 d of age had higher (P < 0.001) ADG than broilers that were fed mash. Also, broilers that were fed pellets had better (P < 0.05) F:G than broilers fed mash, with broilers fed crumbles being intermediate. Broilers fed the USA-2 meal had higher (P < 0.01) ADG than broilers fed the BRA or the ARG meals, with broilers fed the USA-1 meal being intermediate. Feed efficiency tended (P = 0.07) to be hindered in broilers fed the BRA meal. The results show that pelleting improved growth performance of broilers from 1 to 42 d of age with effects being less evident at 42 d than at 21 d of age. Source of SBM affected growth performance suggesting the need for a better control of chemical composition and quality of this ingredient before diet formulation.

  19. Training To Improve Manual Control In 7–8 And 10–12 Year Old Children: Training Eliminates Performance Differences Between Ages

    PubMed Central

    Snapp-Childs, Winona; Fath, Aaron J.; Watson, Carol A; Flatters, Ian; Mon-Williams, Mark; Bingham, Geoffrey P.

    2015-01-01

    Many children have difficulty producing movements well enough to improve in perceptuo-motor learning. We have developed a training method that supports active movement generation to allow improvement in a 3D tracing task requiring good compliance control. We previously tested 7–8 year old children who exhibited poor performance and performance differences before training. After training, performance was significantly improved and performance differences were eliminated. According to the Dynamic Systems Theory of development, appropriate support can enable younger children to acquire the ability to perform like older children. In the present study, we compared 7–8 and 10–12 year old school children and predicted that younger children would show reduced performance that was nonetheless amenable to training. Indeed, the pre-training performance of the 7–8 year olds was worse than that of the 10–12 year olds, but post-training performance was equally good for both groups. This was similar to previous results found using this training method for children with DCD and age-matched typically developing children. We also found in a previous study of 7–8 year old school children that training in the 3D tracing task transferred to a 2D drawing task. We now found similar transfer for the 10–12 year olds. PMID:26241334

  20. A moderate swimming exercise regularly performed throughout the life induces age and sex-related modifications in adaptive macronutrients choice.

    PubMed

    Boghossian, S; Alliot, J

    2000-12-01

    The ability of laboratory rats to adapt food intake to needs is well-known. The present study investigates changes in this adaptive behavior when animals grow old. A cohort of male and female Lou/c/jall rats was regularly submitted to an exercise throughout their life (6 consecutive days of moderate intensity training (3x15 min/day)). Caloric intake and macronutrients selection during exercise and post-exercise periods were compared to the pre-training period. During swimming, a decrease in both caloric intake and fat selection was observed and an increase in protein intake was specifically seen in female groups. However, males were unable to modify the diet composition (macronutrient rate) from 16 months of age, whereas females were able to do it until 24 months of age. The present results suggest a sex-dependent loss of capacity of adjusting feeding behavior to metabolic needs when animals grow old, may be due to a deterioration of the central control of food intake.

  1. International Research Project on the Effects of Chemical Ageing of Polymers on Performance Properties: Chemical and Thermal Analysis

    NASA Technical Reports Server (NTRS)

    Bulluck, J. W.; Rushing, R. A.

    1996-01-01

    Work during the past six months has included significant research in several areas aimed at further clarification of the aging and chemical failure mechanism of thermoplastics (PVDF or Tefzel) pipes. Among the areas investigated were the crystallinity changes associated with both the Coflon and Tefzel after various simulated environmental exposures using X-ray diffraction analysis. We have found that significant changes in polymer crystallinity levels occur as a function of the exposures. These crystallinity changes may have important consequences on the fracture, fatigue, tensile, and chemical resistance of the materials. We have also noted small changes in the molecular weight distribution. Again these changes may result in variations in the mechanical and chemical properties in the material. We conducted numerous analytical studies with methods including X-ray Diffraction, Gel Permeation Chromatography, Fourier Transform Infrared Spectroscopy, Ultra- Violet Scanning Analysis, GC/Mass Spectrometry, Differential Scanning Calorimetry and Thermomechanical Analysis. In the ultra-violet analysis we noted the presence of an absorption band indicative of triene formation. We investigated a number of aged samples of both Tefzel and Coflon that were forwarded from MERL. We also cast films at SWT and subjected these films to a refluxing methanol 1% ethylene diamine solution. An updated literature search was conducted using Dialog and DROLLS to identify any new papers that may have been published in the open literature since the start of this project. The updated literature search and abstracts are contained in the Appendix section of this report.

  2. Effects of Dietary Calcium Levels on Productive Performance, Eggshell Quality and Overall Calcium Status in Aged Laying Hens.

    PubMed

    An, S H; Kim, D W; An, B K

    2016-10-01

    This study was conducted to investigate the effects of diets with varying levels of calcium on egg production, shell quality and overall calcium status in aged laying hens. A total of five hundred 70-wk-old Hy-Line Brown layers were divided five groups and fed one of the five experimental diets with 3.5%, 3.8%, 4.1%, 4.4%, or 4.7% Ca, for 10 weeks. There were no significant differences in feed intake, egg production and egg weight among groups. The cracked eggs were linearly reduced as dietary Ca levels increased to 4.7% (p<0.01). A significant linear improvement for eggshell strength and thickness were determined with increasing dietary Ca levels (p<0.01). The contents of serum Ca and phosphorus were not affected by dietary Ca levels. With increase in dietary Ca levels, the tibial breaking strength slightly increased. There were no significant differences in the tibial contents of ash, Ca and phosphorus among groups. In conclusion, eggshell quality, as measured by appearance, strength and thickness of eggshell, were influenced by dietary Ca content as expected (p<0.05). These results suggested that aged laying hens require relatively higher level of Ca than required levels from current Korean feeding standards for poultry.

  3. Clinical implications of daytime sleepiness for the academic performance of middle school-aged adolescents with attention deficit hyperactivity disorder.

    PubMed

    Langberg, Joshua M; Dvorsky, Melissa R; Marshall, Stephen; Evans, Steven W

    2013-10-01

    This study investigated the relative impact of total time slept per night and daytime sleepiness on the academic functioning of 100 middle school-aged youth (mean age = 11.9) with attention deficit hyperactivity disorder (ADHD). The primary goal of the study was to determine if total time slept per night and/or daytime sleepiness, as measured by youth self-report on the Pediatric Daytime Sleepiness Scale (PDSS), predicted academic functioning above and beyond symptoms of ADHD and relevant covariates, such as intelligence, achievement scores and parent education level. Self-reported daytime sleepiness but not self-reported total time slept per night was associated significantly with all academic outcomes. When examined in a hierarchical regression model, self-reported daytime sleepiness significantly predicted parent-rated homework problems and academic impairment and teacher-rated academic competence above and beyond symptoms of ADHD and relevant covariates, but did not predict grade point average or teacher-rated academic impairment. The implications of these findings for understanding more clearly the association between ADHD and sleep and the functional implications of this relationship are discussed.

  4. Effects of Dietary Calcium Levels on Productive Performance, Eggshell Quality and Overall Calcium Status in Aged Laying Hens

    PubMed Central

    An, S. H.; Kim, D. W.; An, B. K.

    2016-01-01

    This study was conducted to investigate the effects of diets with varying levels of calcium on egg production, shell quality and overall calcium status in aged laying hens. A total of five hundred 70-wk-old Hy-Line Brown layers were divided five groups and fed one of the five experimental diets with 3.5%, 3.8%, 4.1%, 4.4%, or 4.7% Ca, for 10 weeks. There were no significant differences in feed intake, egg production and egg weight among groups. The cracked eggs were linearly reduced as dietary Ca levels increased to 4.7% (p<0.01). A significant linear improvement for eggshell strength and thickness were determined with increasing dietary Ca levels (p<0.01). The contents of serum Ca and phosphorus were not affected by dietary Ca levels. With increase in dietary Ca levels, the tibial breaking strength slightly increased. There were no significant differences in the tibial contents of ash, Ca and phosphorus among groups. In conclusion, eggshell quality, as measured by appearance, strength and thickness of eggshell, were influenced by dietary Ca content as expected (p<0.05). These results suggested that aged laying hens require relatively higher level of Ca than required levels from current Korean feeding standards for poultry. PMID:26954217

  5. Vascular Function, Cerebral Cortical Thickness, and Cognitive Performance in Middle-Aged Hispanic and Non-Hispanic Caucasian Adults

    PubMed Central

    Pasha, Evan; Kaur, Sonya S.; Gonzales, Mitzi M.; Machin, Daniel R.; Kasischke, Kennon; Tanaka, Hirofumi; Haley, Andreana P.

    2015-01-01

    Hispanics are at increased risk of acquiring cardiovascular risk factors that contribute to cognitive dysfunction. To compare indices of vascular health to measures of cerebral gray matter integrity, 60 middle-aged Hispanic and non-Hispanic Caucasian participants were matched across age, gender, years of education, and mental status. Arterial stiffness was characterized via β-stiffness index and carotid-femoral pulse-wave velocity, and magnetic resonance imaging estimated cortical thickness in a priori regions of interest known to be susceptible to vascular risk factors. Measures of arterial stiffness were significantly higher in Hispanics than in non-Hispanic Caucasians. Hispanics exhibited thinner left inferior frontal gyrus (LIFG) cortical thickness (p=0.04) with concurrently lower language (p=0.02), memory (p=0.03), and attention-executive functioning (p=0.02). These results suggest that compromised vascular health may occur simultaneously with cortical thinning of the LIFG as an early neuropathological alteration in Hispanics. PMID:25720950

  6. Administration on Aging

    MedlinePlus

    ... Administration on Aging Administration on Disabilities Center for Integrated Programs Center for Performance and Evaluation National Institute ... Project Aging Statistics Profile of Older Americans AGing Integrated Database (AGID) Census Data & Population Estimates Projected Future ...

  7. Effect of temperature-humidity index on live performance in broiler chickens grown from 49 to 63 days of age

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The thermal environment in poultry housing is a primary influence on production efficiency and live performance. Heavy broilers (body weight > 3.2 kg) typically require high ventilation rates to maintain thermal comfort and production efficiency. However, large birds are observed to pant in mild to ...

  8. The Math Gap: A Description of the Mathematics Performance of Preschool-Aged Deaf/Hard-of-Hearing Children

    ERIC Educational Resources Information Center

    Pagliaro, Claudia M.; Kritzer, Karen L.

    2013-01-01

    Over decades and across grade levels, deaf/hard-of-hearing (d/hh) student performance in mathematics has shown a gap in achievement. It is unclear, however, exactly when this gap begins to emerge and in what areas. This study describes preschool d/hh children's knowledge of early mathematics concepts. Both standardized and nonstandardized measures…

  9. Analysis of Production Errors in the Phonetic Performance of School-Age Standard-English-Speaking Children. Final Report.

    ERIC Educational Resources Information Center

    Williams, Frederick, Ed.; And Others

    This study is concerned with misarticulated speech sounds of children and the phonetic realization of these sounds. The articulation errors of 384 standard-English-speaking school children were analyzed in speech samples obtained by the National Speech and Hearing Survey and were samples of both free speech and of performance on the…

  10. Driving performance changes of middle-aged experienced taxi drivers due to distraction tasks during unexpected situations.

    PubMed

    Kim, Hyung-Sik; Choi, Mi-Hyun; Choi, Jin-Seung; Kim, Hyun-Joo; Hong, Sang-Pyo; Jun, Jae-Hoon; Tack, Gye-Rae; Kim, Boseong; Min, Ung-Chan; Lim, Dae-Woon; Chung, Soon-Cheol

    2013-10-01

    This study investigated the effects of distraction taskssuch as sending a text message with a cellphone and searching navigation with car navigation system-on the driving performance of 29 highly experienced taxi drivers in their 50s. All participants were instructed to drive using a driving simulator for 2 min. while maintaining a constant distance from the vehicle in front and a constant speed. Participants drove without any distractions for the first minute. For an additional minute, they performed Driving Only or performed a task while driving (Driving + Sending Text Message or Driving + Searching Navigation). An unexpected situation, in which the participant had to stop abruptly due to a sudden stop of the preceding vehicle, occurred during this period. Driving performance during the unexpected situation was evaluated by car control variables, medial-lateral coefficient of variation and brake time, and by motion variables such as the jerk-cost function. Compared to Driving Only, jerk-cost function, medial-lateral coefficient of variation, and brake time increased during Driving + Sending Text Message or Driving + Searching Navigation.

  11. A Research-Based Community Theater Performance to Promote Ageing: Is It More than Just a Show?

    ERIC Educational Resources Information Center

    Feldman, Susan; Radermacher, Harriet; Lorains, Felicity; Haines, Terence

    2011-01-01

    Research-based community theater can address important life issues in a safe and entertaining environment. This study investigated using a theater performance about widowhood as a medium for facilitating older people's engagement with key life events and countering negative stereotypes. Quantitative questions incorporating semistructured…

  12. Brain Gym To Increase Academic Performance Of Children Aged 10-12 Years Old ( Experimental Study in Tembalang Elementary School and Pedalangan Elementary School Semarang)

    NASA Astrophysics Data System (ADS)

    Marpaung, M. G.; Sareharto, T. P.; Purwanti, A.; Hermawati, D.

    2017-02-01

    Academic performance becomes an important determinant of individual quality. it is determined by the function of affective, cognitive, psychomotor, and intelligence. Brain gym can improve learning processes and integrate all areas that related to the learning process. To prove the effect of brain gym towards academic performance of children aged 10-12 years. This study was a quasy experiment study with one group pre and post test design. Samples (n=18 male=7 and female=11) were taken from five and six grader and conducted in Tembalang and Pedalangan Elementary School, Semarang. Pretest were administered, followed by brain gym, and post test administered in the end of study. The measurement of Intelligence Quotient pre and post test using Culture Fair Intelligence Test Scale 2. Among the 18 subjects (male=7 and female=11) the average of academic performance and IQ score after brain gym showed improvement. The Improvement of IQ score with Culture Fair Test Scale 2 was analyzed by Dependent T test showed significant results (p=0,000). The improvement of Bahasa score was analyzed by Wilcoxon test showed significant results (p=0,001), an unsignificant result were shown in Mathematics p=0,079 and natural sciences p=0,306. Brain gym can increase academic performance of children aged 10-12 years old.

  13. Detailed analysis of the behavior and memory performance of middle-aged male and female CD-1 mice in a 3D maze.

    PubMed

    Ennaceur, A; Michalikova, S; van Rensburg, R; Chazot, P L

    2008-03-05

    Fifty percent of CD-1 mice from both sex die by the end of 2 years. The survival rate is higher in females than in males. This high mortality rate is associated to the high susceptibility of this strain of mice to some immuno-pathologies and the high incidence of systemic amyloidosis. It is therefore possible that premature cognitive deficits can be observed in CD-1 mice. In the present study, we describe a novel method for assessing emotional responses and memory performance of young (4 months) and middle-aged (12 months) CD-1 mice of both sexes in a 3D spatial navigation task. Animals are introduced to the maze without preliminary habituation and trained in a working memory test. As expected CD-1 mice have a low number of entries to arms on their first exposure to the maze which confirm our previous report on the anxious trait of this strain compared to C57/BL6 mice. The measure of arm/bridge ratio suggests that anxiety induced by exposure to the maze persists much longer in middle-aged male mice compared to middle-aged female mice and compared to both young male and female mice. The measure of memory revealed that young female mice made significantly less arm repeats and more unique arm visits before first arm repeat than middle-aged female and male mice. There are also significant differences between young female and young male mice with the former committing fewer errors than the latter.

  14. The Math Gap: a description of the mathematics performance of preschool-aged deaf/hard-of-hearing children.

    PubMed

    Pagliaro, Claudia M; Kritzer, Karen L

    2013-04-01

    Over decades and across grade levels, deaf/hard-of-hearing (d/hh) student performance in mathematics has shown a gap in achievement. It is unclear, however, exactly when this gap begins to emerge and in what areas. This study describes preschool d/hh children's knowledge of early mathematics concepts. Both standardized and nonstandardized measures were used to assess understanding in number, geometry, measurement, problem solving, and patterns, reasoning and algebra. Results present strong evidence that d/hh students' difficulty in mathematics may begin prior to the start of formal schooling. Findings also show areas of strength (geometry) and weakness (problem solving and measurement) for these children. Evidence of poor foundational performance may relate to later academic achievement.

  15. Association of Physical Performance and Pain With Fear of Falling Among Community-Dwelling Japanese Women Aged 65 Years and Older.

    PubMed

    Tomita, Yoshihito; Arima, Kazuhiko; Kanagae, Mitsuo; Okabe, Takuhiro; Mizukami, Satoshi; Nishimura, Takayuki; Abe, Yasuyo; Goto, Hisashi; Horiguchi, Itsuko; Aoyagi, Kiyoshi

    2015-09-01

    Our aim was to explore the association of physical performance and pain with fear of falling among community-dwelling Japanese women.The subjects were 278 women aged 65 years and over. We collected information on fear of falling, painful joints, comorbidities, falls in the previous year, and cataracts. Walking time (distance of 6 m), chair stand time (5 times), grip strength, the timed up and go test (TUG), and functional reach were measured.The prevalence of fear of falling was 36.3%, and it increased with age, but it was not significant (P = 0.081). Multivariate logistic regression analysis showed that poor physical performance (longer walking time, longer chair stand time, weaker grip strength, and longer TUG) and pain (low back, and upper and lower extremity pain) were significantly associated with fear of falling after adjusting for age, body mass index, comorbidities, falls in the previous year, and cataracts.Maintaining physical functioning and managing pain may be important for elderly women with fear of falling.

  16. Change of the age and performance of swimmers across World Championships and Olympic Games finals from 1992 to 2013 - a cross-sectional data analysis.

    PubMed

    König, Stefan; Valeri, Fabio; Wild, Stefanie; Rosemann, Thomas; Rüst, Christoph Alexander; Knechtle, Beat

    2014-01-01

    The aims of the present study were to investigate the changes in the age and in swimming performance of finalists in World Championships (1994-2013) and Olympic Games (1992-2012) competing in all events/races (stroke and distance). Data of 3,295 performances from 1,615 women and 1,680 men were analysed using correlation analyses and magnitudes of effect sizes. In the World Championships, the age of the finalists increased for all strokes and distances with exception of 200 m backstroke in women, and 400 m freestyle and 200 m breaststroke in men where the age of the finalists decreased. The magnitudes of the effects were small to very large (mean ± SD 2.8 ± 2.7), but extremely large (13.38) for 1,500 m freestyle in women. In the Olympic Games, the age of the finalists increased for all strokes and distances with exception of 800 m freestyle in women and 400 m individual medley in men. The magnitudes of the effects were small to very large (mean ± SD 4.1 ± 7.1), but extremely large for 50 m freestyle in women (10.5) and 200 m butterfly in men (38.0). Swimming performance increased across years in both women and men for all strokes and distances in both the World Championships and the Olympic Games. The magnitudes of the effects were all extremely large in World Championships (mean ± SD 20.1 ± 8.4) and Olympic Games (mean ± SD 52.1 ± 47.6); especially for 100 m and 200 m breaststroke (198) in women in the Olympic Games. To summarize, in the last ~20 years the age of the finalists increased in both the World Championships and the Olympic Games with some minor exceptions (200 m backstroke in women, 400 m freestyle and 200 m breaststroke in men in World Championships and 800 m freestyle in women and 400 m individual medley in men in Olympic Games) and performance of the finalists improved.

  17. Individual Differences and Age-Related Performance Assessment in Naval Aviators. Part 1. Battery Development and Assessment.

    DTIC Science & Technology

    1982-09-01

    press. Dichotic listening. This task, described in detail by Gopher (1982) presents subjects with a series of word and digit pairs, simultaneously... Digit Recall + 2nd-order tracking: # correct .70 RT .67 RMS .86 Dichotic Listening Task: 1. Omissions: ff correct .93 2. Intrusions: # corre(:t .89 3...speed, a running memory task, .racking tasks performed alone and with the memory tasks, a dichotic listening task, and a computerized version of three

  18. Neurodevelopmental performance among school age children in rural Guatemala is associated with prenatal and postnatal exposure to carbon monoxide, a marker for exposure to woodsmoke.

    PubMed

    Dix-Cooper, Linda; Eskenazi, Brenda; Romero, Carolina; Balmes, John; Smith, Kirk R

    2012-03-01

    We investigated whether early life chronic exposure to woodsmoke, using personal passive 48-h carbon monoxide (CO) as an indicator, is associated with children's neurodevelopmental and behavioral performance. CO measures were collected every 3 months from 2002 to 2005 among mother-child dyads during the Randomized Exposure Study of Pollution Indoors and Respiratory Effects (RESPIRE) stove intervention trial in San Marcos, Guatemala. From March to June, 2010, study children of age 6-7 years, performed a follow-up non-verbal, culturally adapted neurodevelopmental assessment. We found inverse associations between CO exposure of pregnant mothers during their 3rd trimesters (m=3.8ppm ± 3.0ppm; range: 0.6-12.5 ppm) and child neuropsychological performance. Scores on 4 out of 11 neuropsychological tests were significantly associated with mothers' 3rd trimester CO exposures, including visuo-spatial integration (p<0.05), short-term memory recall (p<0.05), long-term memory recall (p<0.05), and fine motor performance (p<0.01) measured using the Bender Gestalt-II's Copy, Immediate Recall, and an adapted version of a Delayed Recall Figures drawing, and the Reitan-Indiana's Finger Tapping Tests, respectively. These 4 significant finding persisted with adjustment for child sex, age, visual acuity, and household assets (socio-economic status). Summary performance scores were also significantly associated with maternal 3rd trimester CO when adjusted for these covariates. Other variables accounting for variance but were excluded in our final multiple regression models included the following: HOME environment stimulation score, child examiner, WHO height-for-age percentile, and age that the infant stopped breastfeeding. This seems to be the first study on woodsmoke exposure and neurodevelopment, and the first longitudinal birth cohort study on chronic early life CO exposures, determined by high quality measures of mothers' and infants' personal CO exposures, and using well

  19. Physical Performance and Physical Activity in Older Adults: Associated but Separate Domains of Physical Function in Old Age

    PubMed Central

    van Lummel, Rob C.; Walgaard, Stefan; Pijnappels, Mirjam; Elders, Petra J. M.; Garcia-Aymerich, Judith; van Dieën, Jaap H.; Beek, Peter J.

    2015-01-01

    Background Physical function is a crucial factor in the prevention and treatment of health conditions in older adults and is usually measured objectively with physical performance tests and/or physical activity monitoring. Objective To examine whether 1) physical performance (PP) and physical activity (PA) constitute separate domains of physical function; 2) differentiation of PA classes is more informative than overall PA. Design Cross-sectional study to explore the relationships within and among PP and PA measures. Methods In 49 older participants (83±7 years; M±SD), performance-based tests were conducted and PA was measured for one week. Activity monitor data were reduced in terms of duration, periods, and mean duration of periods of lying, sitting, standing and locomotion. The relation between and within PP scores and PA outcomes were analysed using rank order correlation and factor analysis. Results Factor structure after varimax rotation revealed two orthogonal factors explaining 78% of the variance in the data: one comprising all PA variables and one comprising all PP variables. PP scores correlated moderately with PA in daily life. Differentiation of activity types and quantification of their duration, intensity and frequency of occurrence provided stronger associations with PP, as compared to a single measure of acceleration expressing overall PA. Limitations For independent validation, the conclusions about the validity of the presented conceptual framework and its clinical implications need to be confirmed in other studies. Conclusions PP and PA represent associated but separate domains of physical function, suggesting that an improvement of PP does not automatically imply an increase of PA, i.e. a change to a more active lifestyle. Differentiation of activity classes in the analysis of PA provides more insights into PA and its association with PP than using a single overall measure of acceleration. PMID:26630268

  20. Fuel Aging in Storage and Transportation (FAST): Accelerated Characterization and Performance Assessment of the Used Nuclear Fuel Storage System

    SciTech Connect

    McDeavitt, Sean

    2016-08-02

    This Integrated Research Project (IRP) was established to characterize key limiting phenomena related to the performance of used nuclear fuel (UNF) storage systems. This was an applied engineering project with a specific application in view (i.e., UNF dry storage). The completed tasks made use of a mixture of basic science and engineering methods. The overall objective was to create, or enable the creation of, predictive tools in the form of observation methods, phenomenological models, and databases that will enable the design, installation, and licensing of dry UNF storage systems that will be capable of containing UNF for extended period of time.

  1. Influence of singing activity, age, and sex on voice performance parameters, on subjects' perception and use of their voice in childhood and adolescence.

    PubMed

    Fuchs, Michael; Meuret, Sylvia; Thiel, Susanne; Täschner, Roland; Dietz, Andreas; Gelbrich, Götz

    2009-03-01

    The aim of the study was to investigate the extent to which regular singing activity and voice training in children and adolescents enhance their voice performance parameters and their perception of their own voice and the extent to which their voice control is improved. At the same time, additional effects of age and sex were also taken into account. We investigated 183 children and adolescents between 6 and 19 years of age (mean age: 13.5 years) and assigned them to groups with different levels of voice strain and training with voice specialists. This was done on the basis of a classification of singing activity which we developed ourselves. We measured the voice parameters, and all of the test subjects were asked to appraise their perception and conscious control of their voices based on a questionnaire comprising 21 items. The higher the degree of vocal strain (taking regularity and organization of singing into consideration) and voice training, the more the perception and conscious control of the voice. Furthermore, the more intense the voice training, the wider the voice range becomes; the stronger the vocal strain, the better the capacity for messa di voce. On the other hand, the maximum duration of sustained phonation unexpectedly decreased, which we attribute to methodological reasons. Older children evince more differentiated perception of the sound of their own voices and imitate other voices more frequently. Boys show better values than girls as far as maximum voice intensity, maximum duration of phonation, and capacity for messa di voce are concerned. Boys also control their voices more consciously than girls. The results underscore the positive effects of regular singing and individual voice training on voice performance, sound perception, and conscious control of the voice. These results should encourage parents and pedagogues to provide opportunities for regular (organized) singing and voice training for as many children as possible. Moreover, age

  2. Evidence for age-related performance degradation of (241)Am foil sources commonly used in UK schools.

    PubMed

    Whitcher, R; Page, R D; Cole, P R

    2014-06-01

    The characteristics of alpha radiation have for decades been demonstrated in UK schools using small sealed (241)Am sources. There is a small but steady number of schools who report a considerable reduction in the alpha count rate detected by an end-window GM detector compared with when the source was new. This cannot be explained by incorrect apparatus or set-up, foil surface contamination, or degradation of the GM detector. The University of Liverpool and CLEAPSS collaborated to research the cause of this performance degradation. The aim was to find what was causing the performance degradation and the ramifications for both the useful and safe service life of the sources. The research shows that these foil sources have greater energy straggling with a corresponding reduction in spectral peak energy. A likely cause for this increase in straggling is a significant diffusion of the metals over time. There was no evidence to suggest the foils have become unsafe, but precautionary checks should be made on old sources.

  3. Orbitofrontal cortex volume in area 11/13 predicts reward devaluation, but not reversal learning performance, in young and aged monkeys.

    PubMed

    Burke, Sara N; Thome, Alex; Plange, Kojo; Engle, James R; Trouard, Theodore P; Gothard, Katalin M; Barnes, Carol A

    2014-07-23

    The orbitofrontal cortex (OFC) and amygdala are both necessary for decisions based on expected outcomes. Although behavioral and imaging data suggest that these brain regions are affected by advanced age, the extent to which aging alters appetitive processes coordinated by the OFC and the amygdala is unknown. In the current experiment, young and aged bonnet macaques were trained on OFC- and amygdala-dependent tasks that test the degree to which response selection is guided by reward value and can be adapted when expected outcomes change. To assess whether the structural integrity of these regions varies with levels of performance on reward devaluation and object reversal tasks, volumes of areas 11/13 and 14 of the OFC, central/medial (CM), and basolateral (BL) nuclei of the amygdala were determined from high-resolution anatomical MRIs. With age, there were significant reductions in OFC, but not CM and BL, volume. Moreover, the aged monkeys showed impairments in the ability to associate an object with a higher value reward, and to reverse a previously learned association. Interestingly, greater OFC volume of area 11/13, but not 14, was significantly correlated with an animal's ability to anticipate the reward outcome associated with an object, and smaller BL volume was predictive of an animal's tendency to choose a higher value reward, but volume of neither region correlated with reversal learning. Together, these data indicate that OFC volume has an impact on monkeys' ability to guide choice behavior based on reward value but does not impact ability to reverse a previously learned association.

  4. Cortical thickness correlates of specific cognitive performance accounted for by the general factor of intelligence in healthy children aged 6 to 18.

    PubMed

    Karama, Sherif; Colom, Roberto; Johnson, Wendy; Deary, Ian J; Haier, Richard; Waber, Deborah P; Lepage, Claude; Ganjavi, Hooman; Jung, Rex; Evans, Alan C

    2011-04-15

    Prevailing psychometric theories of intelligence posit that individual differences in cognitive performance are attributable to three main sources of variance: the general factor of intelligence (g), cognitive ability domains, and specific test requirements and idiosyncrasies. Cortical thickness has been previously associated with g. In the present study, we systematically analyzed associations between cortical thickness and cognitive performance with and without adjusting for the effects of g in a representative sample of children and adolescents (N=207, Mean age=11.8; SD=3.5; Range=6 to 18.3 years). Seven cognitive tests were included in a measurement model that identified three first-order factors (representing cognitive ability domains) and one second-order factor representing g. Residuals of the cognitive ability domain scores were computed to represent g-independent variance for the three domains and seven tests. Cognitive domain and individual test scores as well as residualized scores were regressed against cortical thickness, adjusting for age, gender and a proxy measure of brain volume. g and cognitive domain scores were positively correlated with cortical thickness in very similar areas across the brain. Adjusting for the effects of g eliminated associations of domain and test scores with cortical thickness. Within a psychometric framework, cortical thickness correlates of cognitive performance on complex tasks are well captured by g in this demographically representative sample.

  5. Gender difference in cycling speed and age of winning performers in ultra-cycling - the 508-mile "Furnace Creek" from 1983 to 2012.

    PubMed

    Rüst, Christoph Alexander; Rosemann, Thomas; Lepers, Romuald; Knechtle, Beat

    2015-01-01

    We analysed (i) the gender difference in cycling speed and (ii) the age of winning performers in the 508-mile "Furnace Creek 508". Changes in cycling speeds and gender differences from 1983 to 2012 were analysed using linear, non-linear and hierarchical multi-level regression analyses for the annual three fastest women and men. Cycling speed increased non-linearly in men from 14.6 (s = 0.3) km · h(-1) (1983) to 27.1 (s = 0.7) km · h(-1) (2012) and non-linearly in women from 11.0 (s = 0.3) km · h(-1) (1984) to 24.2 (s = 0.2) km · h(-1) (2012). The gender difference in cycling speed decreased linearly from 26.2 (s = 0.5)% (1984) to 10.7 (s = 1.9)% (2012). The age of winning performers increased from 26 (s = 2) years (1984) to 43 (s = 11) years (2012) in women and from 33 (s = 6) years (1983) to 50 (s = 5) years (2012) in men. To summarise, these results suggest that (i) women will be able to narrow the gender gap in cycling speed in the near future in an ultra-endurance cycling race such as the "Furnace Creek 508" due to the linear decrease in gender difference and (ii) the maturity of these athletes has changed during the last three decades where winning performers become older and faster across years.

  6. Cortical Thickness Correlates of Specific Cognitive Performance Accounted for by the General Factor of Intelligence in Healthy Children Aged 6 to 18

    PubMed Central

    Karama, Sherif; Colom, Roberto; Johnson, Wendy; Deary, Ian J.; Haier, Richard; Waber, Deborah P.; Lepage, Claude; Ganjavi, Hooman; Jung, Rex; Evans, Alan C.

    2011-01-01

    Prevailing psychometric theories of intelligence posit that individual differences in cognitive performance are attributable to three main sources of variance: the general factor of intelligence (g), cognitive ability domains, and specific test requirements and idiosyncrasies. Cortical thickness has been previously associated with g. In the present study, we systematically analyzed associations between cortical thickness and cognitive performance with and without adjusting for the effects of g in a representative sample of children and adolescents (N = 207, Mean age = 11.8; SD = 3.5; Range = 6 to 18.3 years). Seven cognitive tests were included in a measurement model that identified three first-order factors (representing cognitive ability domains) and one second-order factor representing g. Residuals of the cognitive ability domain scores were computed to represent g-independent variance for the three domains and seven tests. Cognitive domain and individual test scores as well as residualized scores were regressed against cortical thickness, adjusting for age, gender and a proxy measure of brain volume. g and cognitive domain scores were positively correlated with cortical thickness in very similar areas across the brain. Adjusting for the effects of g eliminated associations of domain and test scores with cortical thickness. Within a psychometric framework, cortical thickness correlates of cognitive performance on complex tasks are well captured by g in this demographically representative sample. PMID:21241809

  7. Forearm muscle quality as a better indicator of physical performance than handgrip strength in older male ground golf players aged 70 to 89

    PubMed Central

    Abe, T.; Thiebaud, R.S.; Loenneke, J.P.

    2016-01-01

    Objectives: To examine the associations between absolute and relative handgrip strength (HGS) and physical performance. Methods: A total of 135 old men aged 70-89 years had muscle thickness (MT) measured by ultrasound at anterior forearm (MT-ulna). Maximum voluntary HGS was measured for the dominant hand. Relative HGS was calculated as ratios of HGS to MT-ulna (HGS/MT-ulna, kg/cm), HGS to forearm girth (HGS/forearm-girth, kg/cm), and HGS to body mass (HGS/body mass, kg/kg). Physical performance was also assessed using the short physical performance battery (SPPB). Results: Age was significantly correlated with absolute and relative HGS (r=-0.479 and r=-0.315 to -0.427, respectively all p<0.001) and physical performance (walking speed, r=-0.218, p=0.011; chair stand, r=0.348, p<0.001), but not with SPPB score (r=-0.083). Absolute HGS was positively correlated with usual-walking speed (r=0.354, p<0.001) and was inversely correlated with chair-stand time (r=-0.386, p<0.001). The strongest correlations were seen between HGS/MT-ulna and usual-walking speed (r=0.426, p<0.001) or chair-stand (r=-0.461, p<0.001). Stepwise regression analysis revealed that HGS/MT-ulna was a significant predictor for U-walk speed (R2=0.205) and chair-stand time (R2=0.241) while absolute HGS was not a significant predictor of either one. Conclusion: Thus, we suggest that forearm muscle quality (HGS/MT-ulna) may be a stronger predictor of physical performance than absolute HGS in active old men. PMID:27973381

  8. A comparison of fathers' and mothers' contributions in the prediction of academic performance of school-age children in Hong Kong.

    PubMed

    Tam, Vicky C W

    2009-04-01

    Asystematic study of the linkages between gender issues and parenting is made among Chinese families. This study examines sex differences in parenting attributes across fathers and mothers and towards sons and daughters, and compares the contributions of fathers and mothers to the prediction of academic performance across boys and girls. Four parenting attributes are included: nurturance, psychological control, parental involvement in education, and parental academic efficacy. Data were collected from 461 Chinese father-mother-child triads of children studying Grade 3 to 5 in Hong Kong. Findings of this study, based on multivariate analysis of variance, showed that parental roles followed traditional Chinese cultural expectations. Compared to the fathers, Chinese mothers of school-age children in Hong Kong were more loving and caring, more involved in children's education, and more efficacious in promoting children's academic performance. Results of hierarchical regression analysis examining the role of child's sex as a moderator showed cross-sex influence in parental contribution to academic performance with respect to parental psychological control and academic efficacy. Specifically, boys benefited more from maternal efficacy than girls did and they were also more hampered by mothers with high psychological control, while girls' academic performance was more enhanced by paternal academic efficacy than boys. A gender-balance approach that highlights the significance of gender in moderating parental contributions to academic performance was thus supported. Future research should continue to focus on psychological control and domain-specific parental attributes as potential sources of gender-linked parent-child associations. Investigations should also explore other cognitive and noncognitive domains of child outcome, different child age groups, as well as Chinese populations in various geographical regions.

  9. Exercise performance and cardiovascular health variables in 70-year-old male soccer players compared to endurance-trained, strength-trained and untrained age-matched men.

    PubMed

    Randers, Morten Bredsgaard; Andersen, Jesper L; Petersen, Jesper; Sundstrup, Emil; Jakobsen, Markus D; Bangsbo, Jens; Saltin, Bengt; Krustrup, Peter

    2014-01-01

    The aim was to investigate performance variables and indicators of cardiovascular health profile in elderly soccer players (SP, n = 11) compared to endurance-trained (ET, n = 8), strength-trained (ST, n = 7) and untrained (UT, n = 7) age-matched men. The 33 men aged 65-85 years underwent a testing protocol including measurements of cycle performance, maximal oxygen uptake (VO2max) and body composition, and muscle fibre types and capillarisation were determined from m. vastus lateralis biopsy. In SP, time to exhaustion was longer (16.3 ± 2.0 min; P < 0.01) than in UT (+48%) and ST (+41%), but similar to ET (+1%). Fat percentage was lower (P < 0.05) in SP (-6.5% points) than UT but not ET and ST. Heart rate reserve was higher (P < 0.05) in SP (104 ± 16 bpm) than UT (+21 bpm) and ST (+24 bpm), but similar to ET (+2 bpm), whereas VO2max was not significantly different in SP (30.2 ± 4.9 ml O2 · min(-1) · kg(-1)) compared to UT (+14%) and ST (+9%), but lower (P < 0.05) than ET (-22%). The number of capillaries per fibre was higher (P < 0.05) in SP than UT (53%) and ST (42%) but similar to ET. SP had less type IIx fibres than UT (-12% points). In conclusion, the exercise performance and cardiovascular health profile are markedly better for lifelong trained SP than for age-matched UT controls. Incremental exercise capacity and muscle aerobic capacity of SP are also superior to lifelong ST athletes and comparable to endurance athletes.

  10. Temporal associations of cigarette smoking with social influences, academic performance, and delinquency: a four-wave longitudinal study from ages 13-23.

    PubMed

    Tucker, Joan S; Martínez, José Felipe; Ellickson, Phyllis L; Edelen, Maria Orlando

    2008-03-01

    This study examined the temporal associations of cigarette smoking with prosmoking social influences, academic performance, and delinquency in a cohort of 6,527 adolescents surveyed at ages 13, 16, 18, and 23 years. Prosmoking peer and family influences were risk factors for future smoking throughout adolescence, with family influences perhaps also operating indirectly through the adolescent's exposure to prosmoking peers. There were reciprocal associations of youth smoking with parental approval, peer smoking, and poor grades (but not delinquency), with youth smoking emerging as a stronger antecedent than consequence of these psychosocial factors. Few gender differences in these associations were observed. Implications of these findings for efforts to prevent youth smoking are discussed.

  11. Assessing the Validity of Self-Rated Health with the Short Physical Performance Battery: A Cross-Sectional Analysis of the International Mobility in Aging Study

    PubMed Central

    Belanger, Emmanuelle; Zunzunegui, Maria–Victoria; Phillips, Susan; Ylli, Alban; Guralnik, Jack

    2016-01-01

    Objective The aim of this study was to explore the validity of self-rated health across different populations of older adults, when compared to the Short Physical Performance Battery. Design Cross-sectional analysis of the International Mobility in Aging Study. Setting Five locations: Saint-Hyacinthe and Kingston (Canada), Tirana (Albania), Manizales (Colombia), and Natal (Brazil). Participants Older adults between 65 and 74 years old (n = 1,995). Methods The Short Physical Performance Battery (SPPB) was used to measure physical performance. Self-rated health was assessed with one single five-point question. Linear trends between SPPB scores and self-rated health were tested separately for men and women at each of the five international study sites. Poor physical performance (independent variable) (SPPB less than 8) was used in logistic regression models of self-rated health (dependent variable), adjusting for potential covariates. All analyses were stratified by gender and site of origin. Results A significant linear association was found between the mean scores of the Short Physical Performance Battery and ordinal categories of self-rated health across research sites and gender groups. After extensive control for objective physical and mental health indicators and socio-demographic variables, these graded associations became non-significant in some research sites. Conclusion These findings further confirm the validity of SRH as a measure of overall health status in older adults. PMID:27089219

  12. Effects of Heat-oxidized Soy Protein Isolate on Growth Performance and Digestive Function of Broiler Chickens at Early Age

    PubMed Central

    Chen, X.; Chen, Y. P.; Wu, D. W.; Wen, C.; Zhou, Y. M.

    2015-01-01

    This study was conducted to investigate effects of heat-oxidized soy protein isolate (HSPI) on growth performance, serum biochemical indices, apparent nutrient digestibility and digestive function of broiler chickens. A total of 320 1-day-old Arbor Acres chicks were randomly divided into 4 groups with 8 replicates of 10 birds, receiving diets containing soy protein isolate (SPI, control group) or the same amount of SPI heated in an oven at 100°C for 1, 4, or 8 h, for 21 days, respectively. The results indicated that compared with the control group, body weight gain and feed intake of birds fed diet containing SPI heated for 8 h were significantly lower (p<0.05). Serum urea nitrogen concentration was higher in the broilers fed diet containing SPI heated for 4 or 8 h at d 21 (p<0.05). In contrast, serum glucose content was decreased by HSPI substitution at d 21 (p<0.05). The relative pancreas weight in HSPI groups was higher than that in the control group at d 21 (p<0.05). Meanwhile, the opposite effect was observed for relative weight of anterior intestine and ileum in broilers fed a diet containing SPI heated for 8 h (p<0.05). Birds fed diets containing SPI heated for 4 or 8 h had a decreased lipase activity in anterior intestinal content at d 14 and 21 (p<0.05), respectively. In addition, the same effect was also noted in broilers given diets containing SPI heated for 1 h at d 21 (p<0.05). Similarly, amylase, protease and trypsin activity in anterior intestinal content were lower in broilers fed diets containing SPI heated for 8 h at d 21 (p<0.05). The apparent digestibility of dry matter (DM) from d 8 to 10 and DM, crude protein (CP), and ether extract from d 15 to 17 were lower in broilers fed diets containing SPI heated for 8 h (p<0.05). Besides, birds given diets containing SPI heated for 4 h also exhibited lower CP apparent digestibility from d 15 to 17 (p<0.05). It was concluded that HSPI inclusion can exert a negative influence on the growth performance of

  13. Growth performance and certain body measurements of ostrich chicks as affected by dietary protein levels during 2-9 weeks of age.

    PubMed

    Mahrose, Kh M; Attia, A I; Ismail, I E; Abou-Kassem, D E; El-Hack, M E Abd

    2015-01-01

    The present work was conducted to examine the effects of dietary crude protein (CP) levels (18, 21 and 24%) on growth performance (Initial and final body weight, daily body weight gain, feed consumption, feed conversion and protein efficiency ratio) during 2-9 weeks of age and certain body measurements (body height, tibiotarsus length and tibiotarsus girth) at 9 weeks of age. A total of 30 African Black unsexed ostrich chicks were used in the present study in simple randomized design. The results of the present work indicated that initial and final live body weight, body weight gain, feed consumption, feed conversion of ostrich chicks were insignificantly affected by dietary protein level used. Protein efficiency ratio was high in the group of chicks fed diet contained 18% CP. Results obtained indicated that tibiotarsus girth was decreased (P≤0.01) with the increasing dietary protein level, where the highest value of tibiotarsus girth (18.38 cm) was observed in chicks fed 18% dietary protein level. Body height and tibiotarsus length were not significantly different. In conclusion, the results of the present study indicate that ostrich chicks (during 2-9 weeks of age) could grow on diets contain lower levels of CP (18%).

  14. Development and validation of a high performance liquid chromatography-diode array detection method for the determination of aging markers in tequila.

    PubMed

    Muñoz-Muñoz, Ana Celia; Grenier, Adam Charles; Gutiérrez-Pulido, Humberto; Cervantes-Martínez, Jesús

    2008-12-12

    A solid-phase extraction procedure followed by analysis by high performance liquid chromatography (HPLC) with UV-vis photodiode array detection (DAD) is proposed to simultaneously determine 11 aging markers in tequila. The method showed good intraday (n=5) and interday (n=3) precision, RSD<1.6% in both cases, for each of the identified compounds. The calibration curves were linear at the tested ranges (R(2)>0.999). Good recoveries (84.2-108.5%) were obtained for 10 of the 11 compounds studied; and the LOD and LOQ ranged from 0.62 to 4.09 microg/mL and 1.9-12.4 microg/mL, respectively. The proposed methodology was applied to a set of 15 authentic tequila samples grouped by aging state (blanco, reposado and añejo). An ANOVA analysis combined with discriminant analysis with stepwise backward variable selection was used to differentiate between the various aging groups based on their oak related compounds content.

  15. Growth performance and certain body measurements of ostrich chicks as affected by dietary protein levels during 2–9 weeks of age

    PubMed Central

    Mahrose, Kh.M.; Attia, A.I.; Ismail, I.E.; Abou-Kassem, D.E.; El-Hack, M.E. Abd

    2015-01-01

    The present work was conducted to examine the effects of dietary crude protein (CP) levels (18, 21 and 24%) on growth performance (Initial and final body weight, daily body weight gain, feed consumption, feed conversion and protein efficiency ratio) during 2-9 weeks of age and certain body measurements (body height, tibiotarsus length and tibiotarsus girth) at 9 weeks of age. A total of 30 African Black unsexed ostrich chicks were used in the present study in simple randomized design. The results of the present work indicated that initial and final live body weight, body weight gain, feed consumption, feed conversion of ostrich chicks were insignificantly affected by dietary protein level used. Protein efficiency ratio was high in the group of chicks fed diet contained 18% CP. Results obtained indicated that tibiotarsus girth was decreased (P≤0.01) with the increasing dietary protein level, where the highest value of tibiotarsus girth (18.38 cm) was observed in chicks fed 18% dietary protein level. Body height and tibiotarsus length were not significantly different. In conclusion, the results of the present study indicate that ostrich chicks (during 2-9 weeks of age) could grow on diets contain lower levels of CP (18%). PMID:26623373

  16. Productive performance of brown-egg laying pullets from hatching to 5 weeks of age as affected by fiber inclusion, feed form, and energy concentration of the diet.

    PubMed

    Guzmán, P; Saldaña, B; Mandalawi, H A; Pérez-Bonilla, A; Lázaro, R; Mateos, G G

    2015-02-01

    The effects of fiber inclusion, feed form, and energy concentration of the diet on the growth performance of pullets from hatching to 5 wk age were studied in 2 experiments. In Experiment 1, there was a control diet based on cereals and soybean meal, and 6 extra diets that included 2 or 4% of cereal straw, sugar beet pulp (SBP), or sunflower hulls (SFHs) at the expense (wt/wt) of the whole control diet. From hatching to 5 wk age fiber inclusion increased (P<0.05) ADG and ADFI, and improved (P<0.05) energy efficiency (EnE; kcal AMEn/g ADG), but body weight (BW) uniformity was not affected. Pullets fed SFH tended to have higher ADG than pullets fed SBP (P=0.072) with pullets fed straw being intermediate. The feed conversion ratio (FCR) was better (P<0.05) with 2% than with 4% fiber inclusion. In Experiment 2, 10 diets were arranged as a 2×5 factorial with 2 feed forms (mash vs. crumbles) and 5 levels of AMEn (2,850, 2,900, 2,950, 3,000, and 3,050 kcal/kg). Pullets fed crumbles were heavier and had better FCR than pullets fed mash (P<0.001). An increase in the energy content of the crumble diets reduced ADFI and improved FCR linearly, but no effects were detected with the mash diets (P<0.01 and P<0.05 for the interactions). Feeding crumbles tended to improve BW uniformity at 5 wk age (P=0.077) but no effects were detected with increases in energy concentration of the diet. In summary, the inclusion of moderate amounts of fiber in the diet improves pullet performance from hatching to 5 wk age. The response of pullets to increases in energy content of the diet depends on feed form with a decrease in feed intake when fed crumbles but no changes when fed mash. Feeding crumbles might be preferred to feeding mash in pullets from hatching to 5 wk age.

  17. Age-related variability in performance of a motor action selection task is related to differences in brain function and structure among older adults.

    PubMed

    Stewart, Jill Campbell; Tran, Xuan; Cramer, Steven C

    2014-02-01

    Task performance for behaviors that engage motor cognitive processes may be particularly sensitive to age-related changes. One well-studied model of cognitive motor function involves engagement of action selection (AS) processes. In young adults, task conditions that add AS demands result in increased preparation times and greater engagement of bilateral dorsal premotor (PMd) and parietal cortices. The current study investigated the behavioral and neural response to a change in motor cognitive demands in older adults through the addition of AS to a movement task. Sixteen older adults made a joystick movement under two conditions during functional magnetic resonance imaging. In the AS condition, participants moved right or left based on an abstract rule; in the execution only (EO) condition, participants moved in the same direction on every trial. Across participants, the AS condition, as compared to the EO condition, was associated with longer reaction time and increased activation of left inferior parietal lobule. Variability in behavioral response to the AS task between participants related to differences in brain function and structure. Overall, individuals with poorer AS task performance showed greater activation in left PMd and dorsolateral prefrontal cortex and decreased structural integrity of white matter tracts that connect sensorimotor, frontal, and parietal regions-key regions for AS task performance. Additionally, two distinct patterns of functional connectivity were found. Participants with a pattern of decreased primary motor-PMd connectivity in response to the AS condition, compared to those with a pattern of increased connectivity, were older and had poorer behavioral performance. These neural changes in response to increased motor cognitive demands may be a marker for age-related changes in the motor system and have an impact on the learning of novel, complex motor skills in older adults.

  18. Effect of milk replacer program on calf performance and digestion of nutrients with age of the dairy calf.

    PubMed

    Chapman, C E; Erickson, P S; Quigley, J D; Hill, T M; Bateman, H G; Suarez-Mena, F X; Schlotterbeck, R L

    2016-04-01

    Calves fed large amounts of milk replacer (MR) gain more body weight preweaning than calves fed less-aggressive programs; however, postweaning growth may be reduced. Limited research suggests that less than optimal digestion of the postweaned diet due to large amounts of MR with reduced dry feed intake preweaning may contribute to growth impairment postweaning. Current research was conducted to compare growth and postweaning digestion in 3-d-old male Holstein calves fed various MR programs. The MR programs were a conventional [CON; 0.44 kg of dry matter (DM) 21% crude protein (CP), 21% fat powder fed for 42d], moderate (MOD; 0.66 kg of DM 27% CP, 17% fat powder fed for 42d), and aggressive program (AGG; up to 0.87 kg of DM 27% CP, 17% fat powder fed for 49d). All calves were fed a 20% CP textured starter and water ad libitum for 56d. The trial used 96 calves (initially 41 ± 1.9 kg of body weight) received 5 wk apart in 2 groups of 48 calves. During d 51 to 56, fecal samples were collected from 5 calves per treatment randomly selected from calves in the first group. Selected nutrients and acid-insoluble ash (used as an internal flow marker) were analyzed in the starter and feces to estimate digestibility. Data were analyzed as a randomized complete block design with starting time of each group of calves as a block. Repeated measure analysis was performed on overall (0 to 56d) data. Means were separated with a protected least significant difference test. Pen was the experimental unit. Calves fed CON had the least average daily gain [CON=0.35, MOD=0.51, and AGG=0.55 kg/d; standard error of the mean (SEM)=0.018], feed efficiency (CON=0.35, MOD=0.49, and AGG=0.48 gain/feed, SEM=0.016), and change in hip width (CON=3.3, MOD=4.1, and AGG=4.1cm, SEM=0.20) compared with calves fed other programs. Calves fed AGG had the greatest change in BCS and least starter intake compared with calves fed the other programs. Digestibility of organic matter was 79, 78, and 68% and neutral

  19. Performance of weld repairs on service-aged 2{1/4}Cr-1Mo girth weldments utilizing conventional postweld heat treatment and temper-bead repair techniques

    SciTech Connect

    Gandy, D.W.; Viswanathan, R.; Findlan, S.J.

    1996-06-01

    Weld repair of service-damaged piping and header girth weldments has generated considerable interest within the fossil power plant arena over the past few years. The interest has stemmed in part from recent revisions to the National Board Inspection Code regarding welding repair of Cr-Mo steels and from the fact that many domestic utility power plants are nearing the end of their projected design life. EPRI is addressing a number of concerns expressed by utilities surrounding weld repair under a joint EPRI/utility program RP3484-01. The program is focused on procuring service-aged piping and header girth weldments, quantifying the level of damage associated with those weldments, performing weld repairs within the girth weldment region, testing the repair weldment mechanically and metallurgically, and comparing the increase or decrease in remaining life associated with the weld repair. This paper discusses four industry case histories along with two piping girth weld repairs performed under the EPRI program: (1) a repair performed with conventional postweld heat treatment and (2) a repair performed employing temper-bead welding repair technology.

  20. A Reanalysis of Cognitive-Functional Performance in Older Adults: Investigating the Interaction Between Normal Aging, Mild Cognitive Impairment, Mild Alzheimer's Disease Dementia, and Depression.

    PubMed

    de Paula, Jonas J; Bicalho, Maria A; Ávila, Rafaela T; Cintra, Marco T G; Diniz, Breno S; Romano-Silva, Marco A; Malloy-Diniz, Leandro F

    2015-01-01

    Depressive symptoms are associated with cognitive-functional impairment in normal aging older adults (NA). However, less is known about this effect on people with mild Cognitive Impairment (MCI) and mild Alzheimer's disease dementia (AD). We investigated this relationship along with the NA-MCI-AD continuum by reanalyzing a previously published dataset. Participants (N = 274) underwent comprehensive neuropsychological assessment including measures of Executive Function, Language/Semantic Memory, Episodic Memory, Visuospatial Abilities, Activities of Daily Living (ADL), and the Geriatric Depression Scale. MANOVA, logistic regression and chi-square tests were performed to assess the association between depression and cognitive-functional performance in each group. In the NA group, depressed participants had a lower performance compared to non-depressed participants in all cognitive and functional domains. However, the same pattern was not observed in the MCI group or in AD. The results suggest a progressive loss of association between depression and worse cognitive-functional performance along the NA-MCI-AD continuum.

  1. A Reanalysis of Cognitive-Functional Performance in Older Adults: Investigating the Interaction Between Normal Aging, Mild Cognitive Impairment, Mild Alzheimer's Disease Dementia, and Depression

    PubMed Central

    de Paula, Jonas J.; Bicalho, Maria A.; Ávila, Rafaela T.; Cintra, Marco T. G.; Diniz, Breno S.; Romano-Silva, Marco A.; Malloy-Diniz, Leandro F.

    2016-01-01

    Depressive symptoms are associated with cognitive-functional impairment in normal aging older adults (NA). However, less is known about this effect on people with mild Cognitive Impairment (MCI) and mild Alzheimer's disease dementia (AD). We investigated this relationship along with the NA-MCI-AD continuum by reanalyzing a previously published dataset. Participants (N = 274) underwent comprehensive neuropsychological assessment including measures of Executive Function, Language/Semantic Memory, Episodic Memory, Visuospatial Abilities, Activities of Daily Living (ADL), and the Geriatric Depression Scale. MANOVA, logistic regression and chi-square tests were performed to assess the association between depression and cognitive-functional performance in each group. In the NA group, depressed participants had a lower performance compared to non-depressed participants in all cognitive and functional domains. However, the same pattern was not observed in the MCI group or in AD. The results suggest a progressive loss of association between depression and worse cognitive-functional performance along the NA-MCI-AD continuum. PMID:26858666

  2. Socioeconomic status, child enrichment factors, and cognitive performance among preschool-age children: results from the Follow-Up of Growth and Development Experiences study.

    PubMed

    Christensen, Deborah L; Schieve, Laura A; Devine, Owen; Drews-Botsch, Carolyn

    2014-07-01

    Lower cognitive performance is associated with poorer health and functioning throughout the lifespan and disproportionately affects children from lower socioeconomic status (SES) populations. Previous studies reporting positive associations between child home enrichment and cognitive performance generally had a limited distribution of SES. We evaluated the associations of SES and child enrichment with cognitive performance in a population with a wide range of SES, particularly whether enrichment attenuates associations with SES. Children were sampled from a case-control study of small-for-gestational-age (SGA) conducted in a public hospital serving a low SES population (final n=198) and a private hospital serving a middle-to-high SES population (final n=253). SES (maternal education and income) and perinatal factors (SGA, maternal smoking and drinking) were obtained from maternal birth interview. Five child home enrichment factors (e.g. books in home) and preschool attendance were obtained from follow-up interview at age 4.5 years. Cognitive performance was assessed with the Differential Ability Scales (DAS), a standardized psychometric test administered at follow-up. SES and enrichment scores were created by combining individual factors. Analyses were adjusted for perinatal factors. Children from the public birth hospital had a significantly lower mean DAS general cognitive ability (GCA) score than children born at the private birth hospital (adjusted mean difference -21.4, 95% CI: -24.0, -18.7); this was substantially attenuated by adjustment for individual SES, child enrichment factors, and preschool attendance (adjusted mean difference -5.1, 95% CI: -9.5, -0.7). Individual-level SES score was associated with DAS score, beyond the general SES effect associated with hospital of birth. Adjustment for preschool attendance and home enrichment score attenuated the association between individual SES score and adjusted mean DAS-GCA among children born at both of the

  3. Effects of dietary L-carnitine and coenzyme Q10 at different supplemental ages on growth performance and some immune response in ascites-susceptible broilers.

    PubMed

    Geng, Ailian; Li, Baoming; Guo, Yuming

    2007-02-01

    Effects of dietary L-carnitine and coenzyme Q10 (CoQ10) at different supplemental ages on performance and some immune response were investigated in ascites-susceptible broilers. A 3 x 2 x 2 factorial design was used consisting of L-carnitine supplementation (0, 75, and 100 mg/kg), CoQ10 supplementation (0 and 40 mg/kg) and different supplemental ages (from day 1 on and from day 10 on). A total of 480 one-day-old Arbor Acre male broiler chicks were randomly allocated to 12 groups, every group had five replicates, each with eight birds. The birds were fed a corn-soybean based diet for six weeks. From day 10-21, all the birds were exposed to a low ambient temperature (12-15 degrees C) to increase the susceptibility to ascites. No significant effects were observed on growth performance by L-carnitine, CoQ10 supplementation, and different supplemental ages. Packed cell volume was significantly decreased by L-carnitine supplementation alone, and ascites heart index and ascites mortality were decreased by L-carnitine, CoQ10 supplementation alone, and L-carnitine + CoQ10 supplementation together (p < 0.05). Heart index of broilers was significantly improved by L-carnitine, CoQ10 supplementation alone during 0-3 week. Serum IgG content was improved by L-carnitine supplementation alone (p < 0.05), but lysozyme activity was increased by L-carnitine + CoQ10 supplementation together (p < 0.05). A significant L-carnitine by supplemental age interaction was observed in lysozyme activity. L-carnitine supplementation alone had no effects on the peripheral blood lymphocyte (PBL) proliferation in response to concanavalin A (ConA) and lipopolysaccharide, but supplemental CoQ10 alone and L-carnitine+ CoQ10 together decreased the PBL proliferation in response to ConA (p < 0.05). The present study suggested that L-carnitine + CoQ10 supplementation together had positive effects on some immune response of ascites-susceptible broilers, which might benefit for the reduction of broilers

  4. Feed form and energy concentration of the diet affect growth performance and digestive tract traits of brown-egg laying pullets from hatching to 17 weeks of age.

    PubMed

    Saldaña, B; Guzmán, P; Cámara, L; García, J; Mateos, G G

    2015-08-01

    The influence of feed form and energy concentration of the diet on growth performance and the development of the gastrointestinal tract (GIT) was studied in brown-egg laying pullets. Diets formed a 2 x 5 factorial with 2 feed forms (mash vs. crumbles) and 5 levels of energy differing in 50 kcal AMEn/kg. For the entire study (0 to 17 wk of age) feeding crumbles increased ADFI (52.9 vs. 49.7 g; P < 0.001) and ADG (12.7 vs. 11.6 g; P < 0.001) and improved feed conversion ratio (FCR; 4.18 vs. 4.27; P < 0.001). An increase in the energy content of the diet decreased ADFI linearly (P < 0.001) and improved FCR quadratically (P < 0.01) but energy intake (kcal AMEn/d) was not affected. BW uniformity was higher (P < 0.05) in pullets fed crumbles than in those fed mash but was not affected (P > 0.05) by energy content of the diet. At 5, 10, and 17 wk of age, the relative weight (RW, % BW) of the GIT and the gizzard, and gizzard digesta content were lower (P < 0.05 to P < 0.001) and gizzard pH was higher (P < 0.05 to P < 0.001) in pullets fed crumbles than in pullets fed mash. Energy concentration of the diet did not affect any of the GIT variables studied. In summary, feeding crumbles improved pullet performance and reduced the RW of the GIT and gizzard, and increased gizzard pH at all ages. An increase in the energy content of the diet improved FCR from 0 to 17 wk of age. The use of crumbles and the increase in the AMEn content of the diet might be used adventageously when the objetive is to increase the BW of the pullets. However, crumbles affected the development and weight of the organs of the GIT, which might have negative effects on feed intake and egg production at the beginning of the egg laying cycle.

  5. Effects of mouse slant and desktop position on muscular and postural stresses, subject preference and performance in women aged 18-40 years.

    PubMed

    Gaudez, Clarisse; Cail, François

    2016-11-01

    This study compared muscular and postural stresses, performance and subject preference in women aged 18-40 years using a standard mouse, a vertical mouse and a slanted mouse in three different computer workstation positions. Four tasks were analysed: pointing, pointing-clicking, pointing-clicking-dragging and grasping-pointing the mouse after typing. Flexor digitorum superficialis (FDS) and extensor carpi radialis (ECR) activities were greater using the standard mouse compared to the vertical or slanted mouse. In all cases, the wrist position remained in the comfort zone recommended by standard ISO 11228-3. The vertical mouse was less comfortable and more difficult to use than the other two mice. FDS and ECR activities, shoulder abduction and wrist extension were greater when the mouse was placed next to the keyboard. Performance and subject preference were better with the unrestricted mouse positioning on the desktop. Grasping the mouse after typing was the task that caused the greatest stress. Practitioner Summary: In women, the slanted mouse and the unrestricted mouse positioning on the desktop provide a good blend of stresses,