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Sample records for age karnofsky performance

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

    PubMed

    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

  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. 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.

  4. P17.27HIGH GRADE GLIOMAS IN ELDERLY PATIENTS: RESULTS OF SURGERY AND INFLUENCE ON KARNOFSKY'S PERFORMANCE STATUS

    PubMed Central

    Agnoletti, A.; Fornaro, R.; Specchia, F.M. Calamo; Garbossa, D.; Lanotte, M.; Ducati, A.

    2014-01-01

    The management of high grade gliomas (HGG) is complex and multidisciplinar. It has been demonstrated that the extent of resection, achieving gross total volume removal (GTR) has a relevant impact on progression free survival (PFS) and on overall survival (OS). Many strategies have been proven to be effective in achieving GTR such as neuronavigation, fluorescence and intra operative ultra sonography. It is remarkable to say that in multicentric trials, often elderly patients were excluded. Recently the interest in results of surgery in elderly patients has grown, and some studies proved the feasibility and advantages of a surgical resection of HGG in elderly patients. We retrospectively analyzed 73 elderly patients (age at diagnosis at least 70 years old) that were affected by HGG in non eloquent areas, therefore amenable to radical surgical excision, that underwent surgical resection in Our division from January 2008 to December 2012. KPS prior to surgery, post surgery and a month after was assessed. OBJECTIVE: Assess the role of surgery on variation of KPS in elderly patients. Materials and methods: we retrospectively analyzed 73 patients, 42 males (57%), 32 ( 43%) females, age range 70-84, mean age 73.87 years old, that underwent surgical excision of newly diagnosed HGG in Our division from January 2008 to December 2012. KPS assessment was performed prior to surgery, and a month after surgery, before adjuvant therapies administration. RESULTS: From data analysis, mean KPS pre-op was 82.5 (overall); mean KPS post operatory (1 month) was 84.5 (overall). 35/73 (47.9%) patients experienced no change in KPS. 24/73 (32%) improved their KPS score, 14/72 (19%) worsened their KPS score. Of the 14 patients which had a worsening in KPS, one month after surgery (before adjuvant treatment), 8 patients recovered, improving their KPS score, which was similar to pre operatory evaluation. The 35 patients that had stability of KPS after surgery, at 1 month after, did not worse

  5. [Use of the Karnofsky index in the evaluation of patients with acute leukemia].

    PubMed

    Sretenović, M; Maksimović, R; Berger, D; Rolović, Z; Petrović, M

    1997-01-01

    The longitudinal study of prospective character was performed during the treatment with the aim to test if Karnofsky's index is an instrument susceptible to the changes in performance status in the population of adult patients with acute leukemia. Performance status points out the person's independence in every day activities and personal care, and more widely, the independence in social and other activities. The aim was to establish its changes in adult patients and its possible prognostic value for the therapy success. The prognostic value of person's activity level was confirmed for the survival length and the lasting, but not for the complete remission achievement. It was concluded that Karnofsky's index was sensitive only for large changes in functional status of acute leukemia patients. PMID:9265374

  6. ‘Just give me the best quality of life questionnaire’: the Karnofsky scale and the history of quality of life measurements in cancer trials

    PubMed Central

    Timmermann, Carsten

    2013-01-01

    Objectives: To use the history of the Karnofsky Performance Scale as a case study illustrating the emergence of interest in the measurement and standardisation of quality of life; to understand the origins of current-day practices. Methods: Articles referring to the Karnofsky scale and quality of life measurements published from the 1940s to the 1990s were identified by searching databases and screening journals, and analysed using close-reading techniques. Secondary literature was consulted to understand the context in which articles were written. Results: The Karnofsky scale was devised for a different purpose than measuring quality of life: as a standardisation device that helped quantify effects of chemotherapeutic agents less easily measurable than survival time. Interest in measuring quality of life only emerged around 1970. Discussion: When quality of life measurements were increasingly widely discussed in the medical press from the late 1970s onwards, a consensus emerged that the Karnofsky scale was not a very good tool. More sophisticated approaches were developed, but Karnofsky continued to be used. I argue that the scale provided a quick and simple, approximate assessment of the ‘soft’ effects of treatment by physicians, overlapping but not identical with quality of life. PMID:23239756

  7. Birthdate and Performance: The Relative Age Effect.

    ERIC Educational Resources Information Center

    Barnsley, Roger H.

    The purpose of this paper is to consider the concept of "relative age" and to review recent research findings that have demonstrated that relative age is related to a variety of academic and athletic performance measures. The paper is divided into six parts: (1) the relative age concept; (2) relative age and achievement in sports; (3) relative age…

  8. 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

  9. Age, human performance, and physical employment standards.

    PubMed

    Kenny, Glen P; Groeller, Herbert; McGinn, Ryan; Flouris, Andreas D

    2016-06-01

    The proportion of older workers has increased substantially in recent years, with over 25% of the Canadian labour force aged ≥55 years. Along with chronological age comes age-related declines in functional capacity associated with impairments to the cardiorespiratory and muscular systems. As a result, older workers are reported to exhibit reductions in work output and in the ability to perform and/or sustain the required effort when performing work tasks. However, research has presented some conflicting views on the consequences of aging in the workforce, as physically demanding occupations can be associated with improved or maintained physical function. Furthermore, the current methods for evaluating physical function in older workers often lack specificity and relevance to the actual work tasks, leading to an underestimation of physical capacity in the older worker. Nevertheless, industry often lacks the appropriate information and/or tools to accommodate the aging workforce, particularly in the context of physical employment standards. Ultimately, if appropriate workplace strategies and work performance standards are adopted to optimize the strengths and protect against the vulnerability of the aging workers, they can perform as effectively as their younger counterparts. Our aim in this review is to evaluate the impact of different individual (including physiological decline, chronic disease, lifestyle, and physical activity) and occupational (including shift work, sleep deprivation, and cold/heat exposure) factors on the physical decline of older workers, and therefore the risk of work-related injuries or illness. PMID:27277571

  10. 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…

  11. 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...

  12. Performing Literature in an Age of Textuality.

    ERIC Educational Resources Information Center

    Bowman, Michael S.

    1996-01-01

    Discusses issues of interpretation versus reading in oral interpretation, or the performance of literature. Offers an extended classroom example to make the case for alternative kinds of performance and their ability to keep practices of performing literature valuable in the current academic scene. (SR)

  13. 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.

  14. 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. PMID:26022534

  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. PMID:19308873

  18. 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.

  19. 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…

  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. 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

  6. 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

  7. Running on age in a 15-km road run: minor influence of age on performance.

    PubMed

    Celie, Floortje; Faes, Miriam; Hopman, Maria; Stalenhoef, Anton F H; Rikkert, Marcel G M Olde

    2010-04-01

    The importance of exercise in the elderly is widely recognized, but data on performances and drop-out in short running contests are lacking. This hinders stimulation and coaching of elderly persons in active aging. The aim of the study was to determine age-related changes in running performance in the most popular Dutch road run, and how this is influenced by gender, training, and increased participation rate over the last decade. This is a retrospective analysis of 194,560 participants of a 15-km run from 1995 to 2007. Multiple regression analysis of running time by age, gender, and training was performed. Trends in participation were examined by chi-square tests and ANOVA. Trends in running time and speed were examined by t tests. With aging, running time increased with 0.20% per year (P < 0.001). Running time was on average 13% (P < 0.001) shorter in men than in women and was 15.7% (P < 0.001) shorter in participants who trained on a regular basis. Decline in performance with age was 5.9% larger for men than women (P < 0.01) and 4.5% larger for trained than untrained participants (P < 0.01). Over the last decade, participation numbers increased most for elderly (≥60 years) and female participants, mean running performance declined with 9.9% (P < 0.001). Drop-out number was low at all ages (0.13-0.29%). It appears that aging has only minor negative influences on running performance, which can even be attenuated by training. Our data suggest that exercise by means of running is a safe and rewarding option for improvement of healthy and active aging. PMID:21124752

  8. Performance efficiency and its changes among aging municipal employees.

    PubMed

    Suvanto, S; Huuhtanen, P; Nygård, C H; Ilmarinen, J

    1991-01-01

    The aims of the study were to compare the performance efficiency of aging municipal workers in different work categories and to determine the changes that occurred in visual search, short-term memory, and fine motor performance over a four-year follow-up period beginning at about 51 years of age. The mental capacity of the workers in mental work was better than that of the workers in physical and mixed physical and mental work, and the results between the physical and mixed work groups did not differ significantly. In four years, the workers' complex short-term memory weakened 6-7% in all three work content groups. Fine motor speed decreased 2-7% in the physical and mental work groups. It was concluded that the mental capacity of older workers depends on the mental demands of their work tasks. The weakening of performance is 2-7% between the ages of 51 to 55 years.

  9. Age effects on attentional blink performance in meditation.

    PubMed

    van Leeuwen, Sara; Müller, Notger G; Melloni, Lucia

    2009-09-01

    Here we explore whether mental training in the form of meditation can help to overcome age-related attentional decline. We compared performance on the attentional blink task between three populations: A group of long-term meditation practitioners within an older population, a control group of age-matched participants and a control group of young participants. Members of both control groups had never practiced meditation. Our results show that long-term meditation practice leads to a reduction of the attentional blink. Meditation practitioners taken from an older population showed a reduction in blink as compared to a control group taken from a younger population, whereas, the control group age-matched to the meditators' group revealed a blink that was comparatively larger and broader. Our results support the hypothesis that meditation practice can: (i) alter the efficiency with which attentional resources are distributed and (ii) help to overcome age-related attentional deficits in the temporal domain.

  10. 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…

  11. 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.

  12. 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

  13. 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.

  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. PMID:26881835

  15. 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.

  16. 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

  17. 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.

  18. 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.

  19. Age-related changes in the performance of forward reach.

    PubMed

    Lin, S I; Liao, C F

    2011-01-01

    Aging is widely considered to be associated with limited balance capacity. It is not clear if forward reach ability is also affected by aging. The purpose of this study was to determine if aging was associated with reduced ability of forward reach or changes in movement patterns. Thirty-three young and 31 older adults were instructed to reach forward as far as possible without losing balance. A motion analysis system was used to record the body kinematics to calculate the joint angle and estimate the motion of center of mass (COM) using a five-segment model. Reach distance (measured from the finger marker), COM displacement, and the distance that the COM exceeded the 2nd toe marker (COM-toe) were used to represent reach performance. The movement patterns were classified as hip, ankle or mixed strategies based upon joint kinematics. It was found that the initial location of the COM was significantly more anterior in the older adults. Older adults were found to have significantly smaller COM displacement and greater hip flexion, but did not differ from young adults in reach distance or COM-toe. Older adults overwhelmingly adopted a hip strategy, but none adopted an ankle strategy. The distribution of the different strategies also differed significantly between groups. These findings suggest that aging appears to be associated with modifications in movement patterns, but not necessarily with a reduction in the ability to approach the boundary of stability. Clinically, balance training for older adults may include the exploration and instruction of atypical movement patterns. PMID:20951591

  20. 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…

  1. The Influence of Subordinate Age on Performance Ratings and Causal Attributions.

    ERIC Educational Resources Information Center

    Ferris, Gerald R.; And Others

    1985-01-01

    Examined the role of subordinate age in performance evaluations. Results found that supervisors rated older subordinates lower than younger subordinates doing the same job; differences between self-ratings of performance and supervisory ratings seemed to be a function of the subordinate's age; and a significant age by performance interaction was…

  2. 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.

  3. The effects of age and sex on mental rotation performance, verbal performance, and brain electrical activity.

    PubMed

    Roberts, Jonathan E; Bell, Martha Ann

    2002-05-01

    This study examined the effects of age and sex on mental rotation performance, verbal performance, and brain-wave activity. Thirty-two 8-year-olds (16 boys) and 32 college students (16 men) had EEG recorded at baseline and while performing four computerized tasks: a two-dimensional (2D) gingerbread man mental rotation, a 2D alphanumeric mental rotation, of three-dimensional (3D) basketball player mental rotation, and lexical decision making. Additionally, participants completed a paper- and pencil water level task and an oral verbal fluency task. On the 2D alphanumeric and 3D basketball player mental rotation tasks, men performed better than boys, but the performance of women and girls did not differ. On the water level task, men performed better than women whereas there was no difference between boys and girls. No sex differences were found on the 2D gingerbread man mental rotation, lexical decision-making, and verbal fluency tasks. EEG analyses indicated that men exhibited left posterior temporal activation during the 2D alphanumeric task and that men and boys both exhibited greater left parietal activation than women and girls during the 2D gingerbread man task. On the 3D basketball player mental rotation task, all participants exhibited greater activation of the right parietal area than the left parietal area. These data give insight into the brain activity and cognitive development changes that occur between childhood and adulthood.

  4. Peak performance and age among superathletes: track and field, swimming, baseball, tennis, and golf.

    PubMed

    Schulz, R; Curnow, C

    1988-09-01

    The purpose of this study is to identify the age of peak performance in a broad range of athletic events incorporating multiple, diverse biological systems, learned skills, and motivation. Although many researchers have noted that the absolute levels of peak performance among superathletes have improved dramatically in the last 100 years, to date no one has answered the question of stability of peak performance age over this time period. Analyses of Olympic track and field and swimming data show that the age at which peak performance is achieved has remained remarkably consistent. For both men and women, the age of peak performance increases with the length of the foot race, and women generally achieve peak performance at younger ages. The pattern of increased age with increasing distance is reversed for female swimmers, where younger ages are associated with increasing distance. For most categories of performance in baseball, the peak age of performance is equivalent to that of a long distance runner, about 28 years of age, while top tennis players reach their highest levels of performance at age 24. Golfers, in comparison, peak at about 31 years of age, although recent data suggest movement toward younger ages. A task analysis of each event is carried out, and the relative roles of biology and learning are discussed as determinants of peak performance.

  5. Age and distraction are determinants of performance on a novel visual search task in aged Beagle dogs.

    PubMed

    Snigdha, Shikha; Christie, Lori-Ann; De Rivera, Christina; Araujo, Joseph A; Milgram, Norton W; Cotman, Carl W

    2012-02-01

    Aging has been shown to disrupt performance on tasks that require intact visual search and discrimination abilities in human studies. The goal of the present study was to determine if canines show age-related decline in their ability to perform a novel simultaneous visual search task. Three groups of canines were included: a young group (N = 10; 3 to 4.5 years), an old group (N = 10; 8 to 9.5 years), and a senior group (N = 8; 11 to 15.3 years). Subjects were first tested for their ability to learn a simple two-choice discrimination task, followed by the visual search task. Attentional demands in the task were manipulated by varying the number of distracter items; dogs received an equal number of trials with either zero, one, two, or three distracters. Performance on the two-choice discrimination task varied with age, with senior canines making significantly more errors than the young. Performance accuracy on the visual search task also varied with age; senior animals were significantly impaired compared to both the young and old, and old canines were intermediate in performance between young and senior. Accuracy decreased significantly with added distracters in all age groups. These results suggest that aging impairs the ability of canines to discriminate between task-relevant and -irrelevant stimuli. This is likely to be derived from impairments in cognitive domains such as visual memory and learning and selective attention.

  6. 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…

  7. Academic Performance Difficulties: Age and Grade at First Referral

    ERIC Educational Resources Information Center

    Harman, Marsha J.; Kordinak, S. Thomas; Bruce, A. Jerry

    2008-01-01

    Archival records of 43 children referred for diagnosis and treatment for academic difficulties were examined. Results revealed a significant difference for age at first referral and diagnoses. Those with disorders such as learning disability and severe emotional disturbance tended to be older, while the ADHD and dysthymic disorders tended to be…

  8. Checking dwelling performance for Aging-in-Place.

    PubMed

    van der Vlies, Remy D; Nauta, Joram; Smit-Rietveld, Charlotte

    2015-01-01

    About 90% of persons aged 55 and older would prefer to stay in their current residences as long as possible because older adults value their independence. However, aging-in-place is not always a choice. Recently, the Dutch government tightened the criteria for older adults to be admitted in a nursing home. Throughout the past 5 years TNO was requested by the trade association for building service contractors in the Netherlands to develop a number of tools for building service professionals. The 'dwelling check' was developed as a 'basic' check on the possibility for aging-in-place. A pilot study was conducted to assess the added value of the dwelling check for older adults. During this pilot study the occupants of over 200 dwellings were interviewed by 11 building services contractors using the dwelling check. Based on these interviews a personal advice was written. After which the interviewees were asked to evaluate this service, comprising the interview and written advice. The dwelling check contributed most to the awareness of and interest in possible alterations for aging-in-place. In a few cases the decision (17%) or even action (5%) was taken to make alterations. Overall the dwelling check was rated 8 out of 10 by the interviewees and may therefore be considered of added value. PMID:26294608

  9. 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…

  10. 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.

  11. 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

  12. 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.

  13. Mobility in Old Age: Capacity Is Not Performance

    PubMed Central

    Mellone, Sabato; Zijlstra, Wiebren

    2016-01-01

    Background. Outcomes of laboratory-based tests for mobility are often used to infer about older adults' performance in real life; however, it is unclear whether such association exists. We hypothesized that mobility capacity, as measured in the laboratory, and mobility performance, as measured in real life, would be poorly linked. Methods. The sample consisted of 84 older adults (72.5 ± 5.9 years). Capacity was assessed via the iTUG and standard gait parameters (stride length, stride velocity, and cadence). Performance was assessed in real life over a period of 6.95 ± 1.99 days using smartphone technology to calculate following parameters: active and gait time, number of steps, life-space, mean action-range, and maximum action-range. Correlation analyses and stepwise multiple regression analyses were applied. Results. All laboratory measures demonstrated significant associations with the real-life measures (between r = .229 and r = .461). The multiple regression analyses indicated that the laboratory measures accounted for a significant but very low proportion of variance (between 5% and 21%) in real-life measures. Conclusion. In older adults without mobility impairments, capacity-related measures of mobility bear little significance for predicting real-life performance. Hence, other factors play a role in how older people manage their daily-life mobility. This should be considered for diagnosis and treatment of mobility deficits in older people. PMID:27034932

  14. The relationship between age and major league baseball performance: implications for development.

    PubMed

    Schulz, R; Musa, D; Staszewski, J; Siegler, R S

    1994-06-01

    Lifetime performance data of 388 baseball players active in 1965 were analyzed to determine the age of peak performance for skills required to play baseball, to derive age-performance curves for athletic productivity, and to assess the magnitude of individual differences among elite and less able players. Cross-sectional and longitudinal analyses show that athletic performance on key indicators rises relatively quickly from age 19 to a peak age of 27 and then declines. The primary difference between elite and less able players is that performance of the elite players remains high for a longer period of time and decays more gradually. The performance of the most elite players is superior to that of less able players even at very early ages. These results parallel findings reported for other achievement domains and can be explained in terms of basic developmental processes involving the interaction of experience, physiological capacity, and motivation.

  15. Anticoccidial drugs and duckling performance to four weeks of age.

    PubMed

    Holderread, D; Nakaue, H S; Arscott, G H

    1983-06-01

    Frequently, publications pertaining to waterfowl state that medicated feeds should not be fed to ducklings and goslings. In some localities, producers and hobbyists who raise a small number of ducklings and goslings can purchase only medicated chick, turkey, or gamebird starter and grower feeds. Because of the lack of documented information on this subject and the numerous requests for advice on this matter, anticoccidial drugs, zoalene, sulfaquinoxaline, and amprolium, were mixed in mash feed and fed to Khaki Campbell male ducklings to 4 weeks of age. No significant differences in mean body weight, mortality, and anatomical development were observed among the treatments. Medicated commercial crumble turkey and chick starter feeds produced significantly better feed conversion than the mash medicated or nonmedicated feeds. These differences can be attributed to greater feed spillage with the mash feed. Some ducklings in all treatments showed unsteadiness of gait and shaky legs. These conditions disappeared when the ducklings were moved from the battery brooder to an outside pen. Zoalene, sulfaquinoxaline, and amprolium used at the recommended levels for chickens and turkeys did not cause any leg or anatomical problems in ducklings.

  16. 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…

  17. The Impact of Perceived Worker Age on Treatment of Experienced and Inexperienced Poor Performers.

    ERIC Educational Resources Information Center

    Barnes-Farrell, Janet L.; Ross, Cheryl L.

    Although there have been numerous studies of age discrimination in the workplace, little research has addressed the issue of corrective actions taken against poorly performing older workers. This study was conducted to examine the effects of both age and tenure on corrective actions recommended for poor performers. Subjects (N=84) were working age…

  18. 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.

  19. The influence of age on reproductive performance of the predatory ladybird beetle, Propylea dissecta.

    PubMed

    Pervez, Ahmad; Omkar; Richmond, Aaron S

    2004-01-01

    The influence of age on reproductive performance of an aphidophagous ladybird beetle, Propylea dissecta was examined using male and female beetles of varying ages (1-30 days) after a single mating stimulus. All the intermediate (10 to 20 days old) and old (30 days old) age females mated with all intermediate and old age males, while only a fraction (0.29%) of younger females, 1 to 5 days old, mated with males of similar or older age. The willingness to mate was male age dependent. It increased sigmoidally with increase in adult age. Adult males were more willing to mate with females irrespective of age. Mating duration was longest amongst older adults (30 day-old males and 20 day-old females). Male age did not contribute to shaping the fecundity of the female ladybird. Fecundity was female age dependent and it increased with age up to 20 days and thereafter decreased. 20 day-old females were most fecund producing 867 eggs after a single mating. Progeny production was male age dependent and eggs sired by 20-30 day-old males had significantly higher viability than those sired by younger males. Prolonged mating increased fecundity and egg viability. The results reveal that males of intermediate age were better mates. This information may improve our understanding of the effect of aging on reproduction in ladybirds and may help mass-multiplication of the ladybird beetles using adults of optimal age.

  20. Effects of age, tenure, training, and job complexity on technical performance.

    PubMed

    Sparrow, P R; Davies, D R

    1988-09-01

    Effects on performance of age, tenure, training level, and job complexity were investigated in a cross-sectional study using a sample of 1,308 service engineers employed by a multinational office equipment company. Two measures of job performance were derived from production record data, one relating to the quality of servicing and the other to the speed with which services were completed. Scores for each performance measure were analyzed by analysis of variance. For the quality of servicing measure, a significant main effect of age and a significant Age X Training interaction were obtained, and the relation between age and job performance took the form of an inverted U. For the speed of servicing measure, the main effects of age, tenure, training level, and job complexity were significant and there were no significant interactions. However, for both performance measures, age accounted for only a very small proportion of the variance. We discuss these results with reference to the existing literature on age and technical job performance, and conclude that training, especially if it is recent, may moderate adverse effects of age on job performance. PMID:3268273

  1. 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 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.

  2. WWER Steam Generators Tubing Performance and Aging Management

    SciTech Connect

    Trunov, Nikolay B.; Davidenko, Stanislav E.; Grigoriev, Vladimir A.; Popadchuk, Valery S.; Brykov, Sergery I.; Karzov, Georgy P.

    2006-07-01

    At WWER NPPs the horizontal steam generators (SGs), are used that differ in design concept from vertical SGs mostly used at western NPPs. Reliable operation of SG heat-exchanging tubes is the crucial worldwide problem for NPP of various types. According to the operation feedback the water chemistry is the governing factor affecting operability of SG tubing. The secondary side corrosion is considered to be the main mechanism of SG heat-exchanging tubes damage at WWER plants. To make the assessment of the tubing integrity the combination of pressure tests and eddy-current tests is used. Assessment of the tubing performance is an important part of SG life extension practice. The given paper deals with the description of the tube testing strategy and the approach to tube integrity assessment based on deterministic and probabilistic methods of fracture mechanics. Requirements for eddy-current test are given as well. Practice of condition monitoring and implementing the database on steam generators operation are presented. The approach to tubes plugging criteria is described. The research activities on corrosion mechanism studies and residual lifetime evaluation are mentioned. (authors)

  3. Examining age differences in performance of a complex information search and retrieval task.

    PubMed

    Czaja, S J; Sharit, J; Ownby, R; Roth, D L; Nair, S

    2001-12-01

    This study examined age differences in performance of a complex information search and retrieval task by using a simulated real-world task typical of those performed by customer service representatives. The study also investigated the influence of task experience and the relationships between cognitive abilities and task performance. One hundred seventeen participants from 3 age groups, younger (20-39 years). middle-aged (40-59 years), and older (60-75 years), performed the task for 3 days. Significant age differences were found for all measures of task performance with the exception of navigational efficiency and number of problems correctly navigated per attempt. There were also effects of task experience. The findings also indicated significant direct and indirect relations between component cognitive abilities and task performance.

  4. Examining age differences in performance of a complex information search and retrieval task.

    PubMed

    Czaja, S J; Sharit, J; Ownby, R; Roth, D L; Nair, S

    2001-12-01

    This study examined age differences in performance of a complex information search and retrieval task by using a simulated real-world task typical of those performed by customer service representatives. The study also investigated the influence of task experience and the relationships between cognitive abilities and task performance. One hundred seventeen participants from 3 age groups, younger (20-39 years). middle-aged (40-59 years), and older (60-75 years), performed the task for 3 days. Significant age differences were found for all measures of task performance with the exception of navigational efficiency and number of problems correctly navigated per attempt. There were also effects of task experience. The findings also indicated significant direct and indirect relations between component cognitive abilities and task performance. PMID:11766912

  5. Sex-related differences and age of peak performance in breaststroke versus freestyle swimming

    PubMed Central

    2013-01-01

    Background Sex-related differences in performance and in age of peak performance have been reported for freestyle swimming. However, little is known about the sex-related differences in other swimming styles. The aim of the present study was to compare performance and age of peak performance for elite men and women swimmers in breaststroke versus freestyle. Methods Race results were analyzed for swimmers at national ranked in the Swiss high score list (during 2006 through 2010) and for international swimmers who qualified for the finals of the FINA World Swimming Championships (during 2003 through 2011). Results The sex-related difference in swimming speed was significantly greater for freestyle than for breaststroke over 50 m, 100 m, and 200 m race distances for Swiss swimmers, but not for FINA finalists. The sex-related difference for both freestyle and breaststroke swimming speeds decreased significantly with increasing swimming distance for both groups. Race distance did not affect the age of peak performance by women in breaststroke, but age of peak performance was four years older for FINA women than for Swiss women. Men achieved peak swimming performance in breaststroke at younger ages for longer race distances, and the age of peak swimming performance was six years older for FINA men than for Swiss men. In freestyle swimming, race distance did not affect the age of peak swimming performance for Swiss women, but the age of peak swimming performance decreased with increasing race distance for Swiss men and for both sexes at the FINA World Championships. Conclusions Results of the present study indicate that (i) sex-related differences in swimming speed were greater for freestyle than for breaststroke for swimmers at national level, but not for swimmers at international level, and (ii) both female and male swimmers achieved peak swimming speeds at younger ages in breaststroke than in freestyle. Further studies are required to better understand differences

  6. Performance Development in Adolescent Track and Field Athletes According to Age, Sex and Sport Discipline

    PubMed Central

    Tønnessen, Espen; Svendsen, Ida Siobhan; Olsen, Inge Christoffer; Guttormsen, Atle; Haugen, Thomas

    2015-01-01

    Introduction Sex-specific differences that arise during puberty have a pronounced effect on the training process. However, the consequences this should have for goal-setting, planning and implementation of training for boys and girls of different ages remains poorly understood. The aim of this study was to quantify performance developments in athletic running and jumping disciplines in the age range 11-18 and identify progression differences as a function of age, discipline and sex. Methods The 100 all-time best Norwegian male and female 60-m, 800-m, long jump and high jump athletes in each age category from 11 to 18 years were analysed using mixed models with random intercept according to athlete. Results Male and female athletes perform almost equally in running and jumping events up to the age of 12. Beyond this age, males outperform females. Relative annual performance development in females gradually decreases throughout the analyzed age period. In males, annual relative performance development accelerates up to the age of 13 (for running events) or 14 (for jumping events) and then gradually declines when approaching 18 years of age. The relative improvement from age 11 to 18 was twice as high in jumping events compared to running events. For all of the analyzed disciplines, overall improvement rates were >50% higher for males than for females. The performance sex difference evolves from < 5% to 10-18% in all the analyzed disciplines from age 11 to 18 yr. Conclusion To the authors’ knowledge, this is the first study to present absolute and relative annual performance developments in running and jumping events for competitive athletes from early to late adolescence. These results allow coaches and athletes to set realistic goals and prescribe conditioning programs that take into account sex-specific differences in the rate of performance development at different stages of maturation. PMID:26043192

  7. Declines in physiological functional capacity with age: a longitudinal study in peak swimming performance

    PubMed Central

    DONATO, ANTHONY J.; TENCH, KATHLEEN; GLUECK, DEBORAH H.; SEALS, DOUGLAS R.; ESKURZA, IRATXE; TANAKA, HIROFUMI

    2016-01-01

    We followed up swimming performance times of 321 women and 319 men who participated in the US Masters Swimming Championships over a 12-yr period. All swimmers placed in the top 10 in their age group over 3 yr (mean = 5 yr). A random coefficients model for repeated measures was used to derive a line of best fit from a group of regression lines for each subject. Both 50- and 1,500-m swimming performance declined modestly until ~70 yr of age, where a more rapid decline was observed in both men and women. Compared with 1,500-m swimming, the 50-m freestyle declined more modestly and slowly with age. The rate and magnitude of declines in swimming performance with age were greater in women than in men in 50-m freestyle; such sex-related differences were not observed in 1,500-m freestyle. Overall, the variability along a population regression line increased markedly with advancing age. The present longitudinal findings indicate that 1) swimming performance declines progressively until age 70, where the decrease becomes quadratic; 2) the rates of the decline in swimming performance with age are greater in a long-duration than in a short-duration event, suggesting a relatively smaller loss of anaerobic muscular power with age compared with cardiovascular endurance; 3) the age-related rates of decline are greater in women than in men only in a short-duration event; and 4) the variability of the age-related decline in performance increases markedly with advancing age. PMID:12391125

  8. 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.

  9. 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

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

    PubMed

    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

  11. 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

  12. The Effect of Age, Sex, Speed and Practice on C/A Performance of Children.

    ERIC Educational Resources Information Center

    Dunham, Paul, Jr.

    This study investigated whether age, sex, speed, and practice affects the acquisition of coincidence-anticipation (C/A) performance accuracy of children ages seven to twelve. (C/A refers to the ability to make a motor response coincident with the arrival of an object at a designated point.) The subjects used in this study were 84 elementary…

  13. Age-Related Decline and Diagnostic Performance of More and Less Prevalent Clinical Cases

    ERIC Educational Resources Information Center

    St-Onge, Christina; Landry, Marjolaine; Xhignesse, Marianne; Voyer, Gilles; Tremblay-Lavoie, Stéphanie; Mamede, Sílvia; Schmidt, Henk; Rikers, Remy

    2016-01-01

    Since cognitive abilities have been shown to decrease with age, it is expected that older physicians would not perform as well as their younger counterparts on clinical cases unless their expertise can counteract the cognitive effects of aging. However, studies on the topic have shown contradictory results. This study aimed to further investigate…

  14. 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…

  15. 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…

  16. Possible Origin of Improved High Temperature Performance of Hydrothermally Aged Cu/Beta Zeolite Catalysts

    SciTech Connect

    Peden, Charles HF; Kwak, Ja Hun; Burton, Sarah D.; Tonkyn, Russell G.; Kim, Do Heui; Lee, Jong H.; Jen, H. W.; Cavattaio, Giovanni; Cheng, Yisun; Lambert, Christine

    2012-04-30

    The hydrothermal stability of Cu/beta NH3 SCR catalysts are explored here. In particular, this paper focuses on the interesting ability of this catalyst to maintain and even enhance high-temperature performance for the "standard" SCR reaction after modest (900 °C, 2 hours) hydrothermal aging. Characterization of the fresh and aged catalysts was performed with an aim to identify possible catalytic phases responsible for the enhanced high temperature performance. XRD, TEM and 27Al NMR all showed that the hydrothermally aging conditions used here resulted in almost complete loss of the beta zeolite structure between 1 and 2 hours aging. While the 27Al NMR spectra of 2 and 10 hour hydrothermally-aged catalysts showed significant loss of a peak associated with tetrahedrally-coordinated Al species, no new spectral features were evident. Two model catalysts, suggested by these characterization data as possible mimics of the catalytic phase formed during hydrothermal aging of Cu/beta, were prepared and tested for their performance in the "standard" SCR and NH3 oxidation reactions. The similarity in their reactivity compared to the 2 hour hydrothermally-aged Cu/beta catalyst suggests possible routes for preparing multi-component catalysts that may have wider temperature windows for optimum performance than those provided by current Cu/zeolite catalysts.

  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.

    1991-12-31

    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.

  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. )

    1991-01-01

    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.

  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. Age-related changes in executive control and their relationships with activity performance in handwriting.

    PubMed

    Rosenblum, Sara; Engel-Yeger, Batya; Fogel, Yael

    2013-04-01

    Deterioration in the frontal and prefrontal cortex associated with executive functions (EF) occurs with age and may be associated with changes in daily performance. The aim of the present study was to describe changes occurring with age in Executive Functions (EF) and handwriting activity, as well as to analyze relationships between age, EF and handwriting performance. The study population included 80 healthy participants (aged 31 to 76+) living in the community. After answering five questions about their writing habits, the participants completed the Behavioral Assessment of the Dysexecutive Syndrome (BADS). In addition, they performed a handwriting task on a digitizer included in the Computerized Penmanship Evaluation Tool (ComPET), which provides kinematic measures of the handwriting process. Significant differences were found between the four age groups for both EF and temporal and spatial handwriting measures. A series of regressions indicated that age predicted 35% of the variance of the BADS profile score (EF control) and 32% of the variance of in-air time while writing. The results of this study indicated age effect on both EF control and handwriting performance. Possible implications for further research and clinical evaluation and intervention are discussed. PMID:23558056

  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. Discrimination performance in aging is vulnerable to interference and dissociable from spatial memory.

    PubMed

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

    2016-07-01

    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 model. In the present study, young and aged F344×BN F1 hybrid rats were cross-characterized on the Morris water maze test of spatial memory and a dentate gyrus-dependent match-to-position test of spatial discrimination ability. Aged rats showed overall impairments relative to young in spatial learning and memory on the water maze task. Although young and aged learned to apply a match-to-position response strategy in performing easy spatial discriminations within a similar number of trials, a majority of aged rats were impaired relative to young in performing difficult spatial discriminations on subsequent tests. Moreover, all aged rats were susceptible to cumulative interference during spatial discrimination tests, such that error rate increased on later trials of test sessions. These data suggest that when faced with difficult discriminations, the aged rats were less able to distinguish current goal locations from those of previous trials. Increasing acetylcholine levels with donepezil did not improve aged rats' abilities to accurately perform difficult spatial discriminations or reduce their susceptibility to interference. Interestingly, better spatial memory abilities were not significantly associated with higher performance on difficult spatial discriminations. This observation, along with the finding that aged rats made more errors under conditions in which interference was high, suggests that match-to-position spatial discrimination performance may rely on extra-hippocampal structures such as the prefrontal cortex, in addition to the dentate gyrus.

  3. Aging and cognitive performance: challenges and implications for physicians practicing in the 21st century.

    PubMed

    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 and potential implications associated with aging. We discuss important findings from other fields and draw parallels to the practice of medicine. In particular, we discuss the possible effects of aging through the lens of situated cognition theory, and we outline the potential impact of aging on expertise, information processing, neurobiology, intelligence, and self-regulated learning. We believe that work done in related fields can provide a better understanding of physician aging and cognition, and thus can inform more effective approaches to continuous professional development and lifelong learning in medicine. We conclude with implications for the health care system and areas of future research.

  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. 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…

  6. Subjective Cognitive Complaints, Memory Performance, and Depressive Affect in Old Age: A Change-Oriented Approach

    ERIC Educational Resources Information Center

    Zimprich, Daniel; Martin, Mike; Kliegel, Matthias

    2003-01-01

    The question of whether and how subjective cognitive complaints are related to actual cognitive performance represents a central issue in applied cognitive aging research. Until recently, however, many studies have failed to find a strong association between subjective cognitive complaints and actual cognitive performance. In our study, we examine…

  7. Academic Performance, Age, Gender, and Ethnicity in Online Courses Delivered by Two-Year Colleges

    ERIC Educational Resources Information Center

    Jost, Bruce; Rude-Parkins, Carolyn; Githens, Rod P.

    2012-01-01

    This study investigated the effects the demographic variables age, gender, and ethnicity and their interactions had on academic performance in online courses delivered by public two-year colleges in Kentucky. The study controlled for previous academic performance measured by cumulative grade point average (GPA). The study used a random sample (N =…

  8. 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.

  9. 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

  10. 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

  11. Sensitivity of negative subsequent memory and task-negative effects to age and associative memory performance.

    PubMed

    de Chastelaine, Marianne; Mattson, Julia T; Wang, Tracy H; Donley, Brian E; Rugg, Michael D

    2015-07-01

    The present fMRI experiment employed associative recognition to investigate the relationships between age and encoding-related negative subsequent memory effects and task-negative effects. Young, middle-aged and older adults (total n=136) were scanned while they made relational judgments on visually presented word pairs. In a later memory test, the participants made associative recognition judgments on studied, rearranged (items studied on different trials) and new pairs. Several regions, mostly localized to the default mode network, demonstrated negative subsequent memory effects in an across age-group analysis. All but one of these regions also demonstrated task-negative effects, although there was no correlation between the size of the respective effects. Whereas negative subsequent memory effects demonstrated a graded attenuation with age, task-negative effects declined markedly between the young and the middle-aged group, but showed no further reduction in the older group. Negative subsequent memory effects did not correlate with memory performance within any age group. By contrast, in the older group only, task-negative effects predicted later memory performance. The findings demonstrate that negative subsequent memory and task-negative effects depend on dissociable neural mechanisms and likely reflect distinct cognitive processes. The relationship between task-negative effects and memory performance in the older group might reflect the sensitivity of these effects to variations in amount of age-related neuropathology. This article is part of a Special Issue entitled SI: Memory. PMID:25264353

  12. Thyroid function, depressed mood, and cognitive performance in older individuals: the Maastricht Aging Study.

    PubMed

    van Boxtel, M P J; Menheere, P P C A; Bekers, O; Hogervorst, E; Jolles, J

    2004-08-01

    The hypothesis was tested that thyroid function, as indicated by serum thyroid-stimulating hormone (TSH) level, is associated with cognitive performance in a healthy aging population. In a random sample of 120 participants recruited from the Maastricht Aging Study (MAAS), aged between 49 and 71 years, we assessed TSH level, mood state (Symptom Check List, subscale depression), and three domains of cognitive function: verbal memory, general sensorimotor speed, and complex flexibility. After correction for age, sex, and educational level, a negative association between TSH and memory function was apparent: higher levels of TSH predicted lower levels of memory performance. Exclusion of individuals with TSH levels suspect for thyroid disorder (n=2) or who were on thyroid replacement (n=3) attenuated this association. Furthermore, additional control for mood status reduced the association below the significance level. No interaction between age and TSH on cognition was found, which indicated that the TSH-memory association was independent of age group level. We conclude that the association between TSH level and memory performance was small and dependent on mood status and the presence of (possible) thyroid disease in this relatively healthy population based sample. Prospective studies are needed to address the role of thyroid function in age-related cognitive decline.

  13. 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. PMID:21174640

  14. 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. PMID:27468992

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

    PubMed

    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

  17. Infant motor development and cognitive performance in early old age: the Helsinki Birth Cohort Study.

    PubMed

    Poranen-Clark, Taina; von Bonsdorff, Mikaela B; Lahti, Jari; Räikkönen, Katri; Osmond, Clive; Rantanen, Taina; Kajantie, Eero; Eriksson, Johan G

    2015-06-01

    Motor development and cognitive development in childhood have been found to be fundamentally interrelated, but less is known about the association extending over the life course. The aim of this study was to examine the association between early motor development and cognitive performance in early old age. From men and women belonging to the Helsinki Birth Cohort Study, who were born between 1934 and 1944 and resided in Finland in 1971, 1279 participated in cognitive performance tests (CogState®, version 3.0.5) between 2001 and 2006 at an average age of 64.2 years (SD 3.0). Of these, age at first walking extracted from child welfare clinic records was available for 398 participants. Longer reaction times in cognitive tasks measuring simple reaction time (SRT), choice reaction time (CRT), working memory (WM), divided attention (DA), and associated learning (AL) indicated poorer cognitive performance. Adjustment was made for sex, age at testing, father's occupational status and own highest attained education, and occupation in adulthood. Average age of learning to walk was 12.2 months (SD 2.1). After adjusting for covariates, earlier attainment of learning to walk was associated with shorter reaction times in cognitive performance tasks (SRT 10.32 % per month, 95 % CI 0.48-21.12, p = 0.039; CRT 14.17 % per month, 95 % CI 3.75-25.63, p = 0.007; WM 15.14 % per month, 95 % CI 4.95-26.32, p = 0.003). People who learned to walk earlier had better cognitive performance in early old age. The earlier attainment of motor skills may track over to early old age and possibly reflect greater cognitive reserve in older age. PMID:25929653

  18. Infant motor development and cognitive performance in early old age: the Helsinki Birth Cohort Study.

    PubMed

    Poranen-Clark, Taina; von Bonsdorff, Mikaela B; Lahti, Jari; Räikkönen, Katri; Osmond, Clive; Rantanen, Taina; Kajantie, Eero; Eriksson, Johan G

    2015-06-01

    Motor development and cognitive development in childhood have been found to be fundamentally interrelated, but less is known about the association extending over the life course. The aim of this study was to examine the association between early motor development and cognitive performance in early old age. From men and women belonging to the Helsinki Birth Cohort Study, who were born between 1934 and 1944 and resided in Finland in 1971, 1279 participated in cognitive performance tests (CogState®, version 3.0.5) between 2001 and 2006 at an average age of 64.2 years (SD 3.0). Of these, age at first walking extracted from child welfare clinic records was available for 398 participants. Longer reaction times in cognitive tasks measuring simple reaction time (SRT), choice reaction time (CRT), working memory (WM), divided attention (DA), and associated learning (AL) indicated poorer cognitive performance. Adjustment was made for sex, age at testing, father's occupational status and own highest attained education, and occupation in adulthood. Average age of learning to walk was 12.2 months (SD 2.1). After adjusting for covariates, earlier attainment of learning to walk was associated with shorter reaction times in cognitive performance tasks (SRT 10.32 % per month, 95 % CI 0.48-21.12, p = 0.039; CRT 14.17 % per month, 95 % CI 3.75-25.63, p = 0.007; WM 15.14 % per month, 95 % CI 4.95-26.32, p = 0.003). People who learned to walk earlier had better cognitive performance in early old age. The earlier attainment of motor skills may track over to early old age and possibly reflect greater cognitive reserve in older age.

  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. 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.

  1. Performance of four age groups of normal elderly on the Rey Auditory-Verbal Learning Test.

    PubMed

    Mitrushina, M; Satz, P; Chervinsky, A; D'Elia, L

    1991-05-01

    This study explored effect of age on encoding, retention, and retrieval components of memory functioning in a sample of 156 healthy, elderly subjects between the ages of 57 and 85, partitioned into four age groups. Memory assessment was based on subjects' performance on the RAVLT, which consisted of five free-recall trials, recall after interference, and recognition trial. Significant group differences in recall were found on all five learning trials, whereas rates of learning, forgetting, and recognition did not differ for four age groups. In addition, primacy/recency effect was equally strong for all groups. Results suggest faulty retrieval mechanisms, whereas encoding and retention processes did not prove to be affected by aging.

  2. Use of a Tracing Task to Assess Visuomotor Performance: Effects of Age, Sex, and Handedness

    PubMed Central

    2013-01-01

    Background. Visuomotor abnormalities are common in aging and age-related disease, yet difficult to quantify. This study investigated the effects of healthy aging, sex, and handedness on the performance of a tracing task. Participants (n = 150, aged 21–95 years, 75 females) used a stylus to follow a moving target around a circle on a tablet computer with their dominant and nondominant hands. Participants also performed the Trail Making Test (a measure of executive function). Methods. Deviations from the circular path were computed to derive an “error” time series. For each time series, absolute mean, variance, and complexity index (a proposed measure of system functionality and adaptability) were calculated. Using the moving target and stylus coordinates, the percentage of task time within the target region and the cumulative micropause duration (a measure of motion continuity) were computed. Results. All measures showed significant effects of aging (p < .0005). Post hoc age group comparisons showed that with increasing age, the absolute mean and variance of the error increased, complexity index decreased, percentage of time within the target region decreased, and cumulative micropause duration increased. Only complexity index showed a significant difference between dominant versus nondominant hands within each age group (p < .0005). All measures showed relationships to the Trail Making Test (p < .05). Conclusions. Measures derived from a tracing task identified performance differences in healthy individuals as a function of age, sex, and handedness. Studies in populations with specific neuromotor syndromes are warranted to test the utility of measures based on the dynamics of tracking a target as a clinical assessment tool. PMID:23388876

  3. 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.

  4. Motor structures in female volleyball players aged 14-17 according to technique quality and performance.

    PubMed

    Katić, Ratko; Grgantov, Zoran; Jurko, Damir

    2006-03-01

    The aim of the study was to identify motor structures in elite female volleyball players aged 14-17, and to assess the effect of these motor structures on their technical and situation efficiency. For this purpose, a battery of 12 motor tests as predictor variables, and a set of six technical elements and evaluation of performance quality as criterion variables were applied in a sample of 147 female volleyballers aged 14-15 and a sample of 50 female volleyballers aged 16-17. Analysis of variance between subgroups within the groups of volleyballers aged 14-15 and those aged 16-17 showed the results on all motor tests to improve with the increase in situation performance, which was especially pronounced in the tests assessing explosive strength and agility. The same held true for the results on all tests assessing volleyball techniques, spike and block in particular. In both samples, factor analysis of motor tests isolated two factors underlain by the generation and regulation of strength, and the mechanism of speed regulation. Canonical correlation analysis between the motor regulatory mechanisms and technical elements revealed determination of the mechanisms of strength and technical efficiency in both samples. Regression correlation analysis showed the mechanisms of strength regulation and speed to be good predictors of game performance in female volleyballers aged 14-15 and 16-17, whereby the mechanism of strength regulation had greater effect on the game performance than the mechanism of speed regulation. Regression correlation analysis also revealed the set of 6 techniques evaluated to be a good predictor of situation efficiency in both groups of female volleyballers aged 14-15 and 16-17. The block and spike techniques were found to be the best predictors of game performance quality in the former, and the techniques of spike and block in the latter. Based on the results obtained, a possible model of selection for supreme score achievement in female volleyball

  5. Implications of advancing paternal age: does it affect offspring school performance?

    PubMed

    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.

  6. Changes in Brain Network Efficiency and Working Memory Performance in Aging

    PubMed Central

    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. PMID:25875001

  7. 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.

  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. Will the age of peak ultra-marathon performance increase with increasing race duration?

    PubMed Central

    2014-01-01

    Background Recent studies found that the athlete’s age of the best ultra-marathon performance was higher than the athlete’s age of the best marathon performance and it seemed that the athlete’s age of peak ultra-marathon performance increased in distance-limited races with rising distance. Methods We investigated the athlete’s age of peak ultra-marathon performance in the fastest finishers in time-limited ultra-marathons from 6 hrs to 10 d. Running performance and athlete’s age of the fastest women and men competing in 6 hrs, 12 hrs, 24 hrs, 48 hrs, 72 hrs, 144 hrs (6 d) and 240 hrs (10 d) were analysed for races held between 1975 and 2012 using analysis of variance and multi-level regression analysis. Results The athlete’s ages of the ten fastest women ever in 6 hrs, 12 hrs, 24 hrs, 48 hrs, 72 hrs, 6 d and 10 d were 41 ± 9, 41 ± 6, 42 ± 5, 46 ± 5, 44 ± 6, 42 ± 4, and 37 ± 4 yrs, respectively. The athlete’s age of the ten fastest women was different between 48 hrs and 10 d. For men, the athlete’s ages were 35 ± 6, 37 ± 9, 39 ± 8, 44 ± 7, 48 ± 3, 48 ± 8 and 48 ± 6 yrs, respectively. The athlete’s age of the ten fastest men in 6 hrs and 12 hrs was lower than the athlete’s age of the ten fastest men in 72 hrs, 6 d and 10 d, respectively. Conclusion The athlete’s age of peak ultra-marathon performance did not increase with rising race duration in the best ultra-marathoners. For the fastest women ever in time-limited races, the athlete’s age was lowest in 10 d (~37 yrs) and highest in 48 hrs (~46 yrs). For men, the athlete’s age of the fastest ever in 6 hrs (~35 yrs) and 12 hrs (~37 yrs) was lower than the athlete’s age of the ten fastest in 72 hrs (~48 yrs), 6 d (~48 yrs) and 10 d (~48 yrs). The differences in the athlete’s age of peak performance between female and male ultra-marathoners for the different race durations need further

  10. Age differences in the performance of basketball dribbling by elementary school boys.

    PubMed

    Caterino, M C

    1991-08-01

    Age differences in hand contact time and ball-to-floor distance during the performance of a basketball dribbling task by 30 5- to 6-, 7- to 8-, and 9- to 10-yr.-old boys were studied. Each age group included 10 boys, five with high rhythm audiation skill and five with low rhythm audiation skill, as measured on Gordon's Primary or Intermediate Measures of Music Audiation. Performance during eight bounces was filmed with a 16-mm camera and analyzed with a stop-action projector. Analysis of variance indicated no statistically significant differences. Observed dribbling behaviors are discussed.

  11. Relationship between anthropometric indicators and cognitive performance in Southeast Asian school-aged children.

    PubMed

    Sandjaja; Poh, Bee Koon; Rojroonwasinkul, Nipa; Le Nyugen, Bao Khanh; Budiman, Basuki; Ng, Lai Oon; Soonthorndhada, Kusol; Xuyen, Hoang Thi; Deurenberg, Paul; Parikh, Panam

    2013-09-01

    Nutrition is an important factor in mental development and, as a consequence, in cognitive performance. Malnutrition is reflected in children's weight, height and BMI curves. The present cross-sectional study aimed to evaluate the association between anthropometric indices and cognitive performance in 6746 school-aged children (aged 6-12 years) of four Southeast Asian countries: Indonesia; Malaysia; Thailand; Vietnam. Cognitive performance (non-verbal intelligence quotient (IQ)) was measured using Raven's Progressive Matrices test or Test of Non-Verbal Intelligence, third edition (TONI-3). Height-for-age z-scores (HAZ), weight-for-age z-scores (WAZ) and BMI-for-age z-scores (BAZ) were used as anthropometric nutritional status indices. Data were weighted using age, sex and urban/rural weight factors to resemble the total primary school-aged population per country. Overall, 21% of the children in the four countries were underweight and 19% were stunted. Children with low WAZ were 3·5 times more likely to have a non-verbal IQ < 89 (OR 3·53 and 95% CI 3·52, 3·54). The chance of having a non-verbal IQ < 89 was also doubled with low BAZ and HAZ. In contrast, except for severe obesity, the relationship between high BAZ and IQ was less clear and differed per country. The odds of having non-verbal IQ levels < 89 also increased with severe obesity. In conclusion, undernourishment and non-verbal IQ are significantly associated in 6-12-year-old children. Effective strategies to improve nutrition in preschoolers and school-aged children can have a pronounced effect on cognition and, in the longer term, help in positively contributing to individual and national development.

  12. Relationship between anthropometric indicators and cognitive performance in Southeast Asian school-aged children.

    PubMed

    Sandjaja; Poh, Bee Koon; Rojroonwasinkul, Nipa; Le Nyugen, Bao Khanh; Budiman, Basuki; Ng, Lai Oon; Soonthorndhada, Kusol; Xuyen, Hoang Thi; Deurenberg, Paul; Parikh, Panam

    2013-09-01

    Nutrition is an important factor in mental development and, as a consequence, in cognitive performance. Malnutrition is reflected in children's weight, height and BMI curves. The present cross-sectional study aimed to evaluate the association between anthropometric indices and cognitive performance in 6746 school-aged children (aged 6-12 years) of four Southeast Asian countries: Indonesia; Malaysia; Thailand; Vietnam. Cognitive performance (non-verbal intelligence quotient (IQ)) was measured using Raven's Progressive Matrices test or Test of Non-Verbal Intelligence, third edition (TONI-3). Height-for-age z-scores (HAZ), weight-for-age z-scores (WAZ) and BMI-for-age z-scores (BAZ) were used as anthropometric nutritional status indices. Data were weighted using age, sex and urban/rural weight factors to resemble the total primary school-aged population per country. Overall, 21% of the children in the four countries were underweight and 19% were stunted. Children with low WAZ were 3·5 times more likely to have a non-verbal IQ < 89 (OR 3·53 and 95% CI 3·52, 3·54). The chance of having a non-verbal IQ < 89 was also doubled with low BAZ and HAZ. In contrast, except for severe obesity, the relationship between high BAZ and IQ was less clear and differed per country. The odds of having non-verbal IQ levels < 89 also increased with severe obesity. In conclusion, undernourishment and non-verbal IQ are significantly associated in 6-12-year-old children. Effective strategies to improve nutrition in preschoolers and school-aged children can have a pronounced effect on cognition and, in the longer term, help in positively contributing to individual and national development. PMID:24016767

  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. PMID:26672872

  14. School-age adopted Chinese girls' behavioral adjustment, academic performance, and social skills: longitudinal results.

    PubMed

    Tan, Tony Xing

    2009-04-01

    Longitudinal data on 177 school-age adopted Chinese girls (Time 1: mean age = 8.92 years, SD = 1.76; Time 2: mean age = 11.18 years, SD = 1.79) were analyzed to determine their long-term outcomes in behavioral adjustment, academic performance (measured with the Child Behavior Checklist/6-18), and social skills (measured with the Social Skills Rating System) and how these outcomes were related to preadoption adversity. More than 90% of the girls were adopted at 24 months or younger (M = 19.25, SD = 21.67). Results revealed that over a 2-year period, there was a moderate to strong stability in the children's behavioral adjustment and academic performance. However, there was a significant increase in the number of children with deviant internalizing problems. At both times, higher degrees of preadoption adversity were related to more internalizing problems and poorer academic performance. Children who were adopted at older ages had poorer academic performance. Children who were older had a lower level of assertion and a higher level of responsibility. Children's attention problems at Time 1 mediated the effect of preadoption adversity on academic performance at Time 2.

  15. 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.

  16. 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.

  17. Comparison of three weaning ages on cow-calf performance and steer carcass traits.

    PubMed

    Myers, S E; Faulkner, D B; Ireland, F A; Parrett, D F

    1999-02-01

    An experiment was conducted to compare three weaning ages on cow-calf performance and steer carcass traits. Crossbred steers (n = 168; 1/2 Simmental x 1/4 Angus x 1/4 Hereford) were randomly assigned to three treatments with eight pens per treatment: groups were 1) weaned at an average of 90 d of age (90 +/- 13 d) and placed in the feedlot, 2) weaned at an average of 152 d of age (152 +/- 13 d) and placed in the feedlot, and 3) weaned at an average of 215 d of age (215 +/- 13 d) and placed in the feedlot. The number of days steers were finished decreased by 55 and 38 d (linear, P = .0001) as weaning age increased when slaughtered at a constant fat end point (.81 cm). Weaning at an average of 90 and 152 d of age improved overall ADG by .15 and .07 kg/d, respectively, over weaning at an average of 215 d of age (linear, P = .005). Over the entire finishing period, intake increased (linear, P = .0006) and efficiency was poorer (linear, P = .004) as weaning age increased. Owing to differences in finishing days and intake, total concentrate consumed increased (linear, P = .03) as weaning age decreased. No differences (P > .21) were observed for carcass weight, longissimus muscle area, or yield grade. No differences (P > .19) were observed in marbling score or percentage of steers grading greater than or equal to Choice or Average Choice. Cow body condition score improved (linear, P = .0001) as weaning age decreased. Pregnancy rate improved 12 percentage units (linear, P = .15) for cows on the 90-d weaning treatment. In this study, early weaning improved gain and feed efficiency, but it increased total concentrate consumed. PMID:10100659

  18. The Relative Age Effect and the Influence on Performance in Youth Alpine Ski Racing

    PubMed Central

    Müller, Lisa; Hildebrandt, Carolin; Raschner, Christian

    2015-01-01

    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 points The relative age influences not only the participation in youth ski

  19. 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

  20. 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

  1. Effects of age and sex on the water maze performance and hippocampal cholinergic fibers in rats.

    PubMed

    Lukoyanov, N V; Andrade, J P; Dulce Madeira, M; Paula-Barbosa, M M

    1999-07-16

    We have examined if age-related deterioration of spatial memory and cholinergic innervation of the dentate gyrus is gender-specific. Aging progressively affected the performance of male and female rats in place discrimination version of the water maze task. On repeated acquisition task, only old males, but not old females, were significantly impaired relative to young and adult animals of both sexes. In parallel, we found that the age-associated reduction of the density of cholinergic fibers in the dentate gyrus was significantly more profound in old males than in age-matched females. These results suggest that, although male and female rats have an identical pattern of reference memory decline, impairment of the working memory and deterioration of the hippocampal cholinergic system are slower to develop in females than in males.

  2. Effects of Vitamin E on Cognitive Performance during Ageing and in Alzheimer’s Disease

    PubMed Central

    La Fata, Giorgio; Weber, Peter; Mohajeri, M. Hasan

    2014-01-01

    Vitamin E is an important antioxidant that primarily protects cells from damage associated with oxidative stress caused by free radicals. The brain is highly susceptible to oxidative stress, which increases during ageing and is considered a major contributor to neurodegeneration. High plasma vitamin E levels were repeatedly associated with better cognitive performance. Due to its antioxidant properties, the ability of vitamin E to prevent or delay cognitive decline has been tested in clinical trials in both ageing population and Alzheimer’s disease (AD) patients. The difficulty in performing precise and uniform human studies is mostly responsible for the inconsistent outcomes reported in the literature. Therefore, the benefit of vitamin E as a treatment for neurodegenerative disorders is still under debate. In this review, we focus on those studies that mostly have contributed to clarifying the exclusive function of vitamin E in relation to brain ageing and AD. PMID:25460513

  3. 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.

  4. Prodynorphin knockout mice demonstrate diminished age-associated impairment in spatial water maze performance.

    PubMed

    Nguyen, Xuan V; Masse, James; Kumar, Ashok; Vijitruth, Rattanavijit; Kulik, Cynthia; Liu, Mei; Choi, Dong-Young; Foster, Thomas C; Usynin, Ivan; Bakalkin, Georgy; Bing, Guoying

    2005-06-20

    Dynorphins, endogenous kappa-opioid agonists widely expressed in the central nervous system, have been reported to increase following diverse pathophysiological processes, including excitotoxicity, chronic inflammation, and traumatic injury. These peptides have been implicated in cognitive impairment, especially that associated with aging. To determine whether absence of dynorphin confers any beneficial effect on spatial learning and memory, knockout mice lacking the coding exons of the gene encoding its precursor prodynorphin (Pdyn) were tested in a water maze task. Learning and memory assessment using a 3-day water maze protocol demonstrated that aged Pdyn knockout mice (13-17 months) perform comparatively better than similarly aged wild-type (WT) mice, based on acquisition and retention probe trial indices. There was no genotype effect on performance in the cued version of the swim task nor on average swim speed, suggesting the observed genotype effects are likely attributable to differences in cognitive rather than motor function. Young (3-6 months) mice performed significantly better than aged mice, but in young mice, no genotype difference was observed. To investigate the relationship between aging and brain dynorphin expression in mice, we examined dynorphin peptide levels at varying ages in hippocampus and frontal cortex of WT 129SvEv mice. Quantitative radioimmunoassay demonstrated that dynorphin A levels in frontal cortex, but not hippocampus, of 12- and 24-month mice were significantly elevated compared to 3-month mice. Although the underlying mechanisms have yet to be elucidated, the results suggest that chronic increases in endogenous dynorphin expression with age, especially in frontal cortex, may adversely affect learning and memory.

  5. Age and individual sleep characteristics affect cognitive performance in anesthesiology residents after a 24-hour shift.

    PubMed

    Tadinac, Meri; Sekulić, Ante; Hromatko, Ivana; Mazul-Sunko, Branka; Ivancić, Romina

    2014-03-01

    Previous research has shown that both shift work and sleep deprivation have an adverse influence on various aspects of human cognitive performance. The aim of this study was to explore changes in cognitive functioning and subjective sleepiness of anesthesiology residents after a 24-hour shift. Twenty-six anesthesiology residents completed a set of psychological instruments at the beginning and at the end of the shift, as well as a questionnaire regarding information about the shift, Stanford Sleepiness Scale, and Circadian Type Questionnaire. There was a significant decline in cognitive performance measured by the Auditory Verbal Learning Test after the shift. The effect was stronger in older participants and in those with high scores on rigidity of sleep scale and low scores on the ability to overcome sleepiness scale. There were no differences in the digits forward test (a measure of concentration), while digits backward test (a measure of working memory) even showed an improved performance after the shift. Although participants reported being significantly sleepier after the shift, the subjective sleepiness did not correlate with any of the objective measures of cognitive performance. In conclusion, the performance in short tasks involving concentration and working memory was not impaired, while performance in long-term and monotone tasks declined after sleep deprivation, and the magnitude of this decline depended on the specific individual characteristics of sleep and on age Surprisingly, age seemed to have an important impact on cognitive functions after shift work even in the relatively age-homogeneous population of young anesthesiology residents.

  6. 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…

  7. 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.

  8. 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…

  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. 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 6-year-olds,…

  11. 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…

  12. 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)

  13. Focus on Opportunities as a Mediator of the Relationships between Age, Job Complexity, and Work Performance

    ERIC Educational Resources Information Center

    Zacher, Hannes; Heusner, Sandra; Schmitz, Michael; Zwierzanska, Monika M.; Frese, Michael

    2010-01-01

    "Focus on opportunities" is a cognitive-motivational facet of occupational future time perspective that describes how many new goals, options, and possibilities individuals expect to have in their personal work-related futures. This study examined focus on opportunities as a mediator of the relationships between age and work performance and…

  14. 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

  15. The neural correlates of recollection and retrieval monitoring: Relationships with age and recollection performance.

    PubMed

    de Chastelaine, Marianne; Mattson, Julia T; Wang, Tracy H; Donley, Brian E; Rugg, Michael D

    2016-09-01

    The relationships between age, retrieval-related neural activity, and episodic memory performance were investigated in samples of young (18-29yrs), middle-aged (43-55yrs) and older (63-76yrs) healthy adults. Participants underwent fMRI scanning during an associative recognition test that followed a study task performed on visually presented word pairs. Test items comprised pairs of intact (studied pairs), rearranged (items studied on different trials) and new words. fMRI recollection effects were operationalized as greater activity for studied pairs correctly endorsed as intact than for pairs incorrectly endorsed as rearranged. The reverse contrast was employed to identify retrieval monitoring effects. Robust recollection effects were identified in the core recollection network, comprising the hippocampus, along with parahippocampal and posterior cingulate cortex, left angular gyrus and medial prefrontal cortex. Retrieval monitoring effects were identified in the anterior cingulate and right dorsolateral prefrontal cortex. Neither recollection effects within the core network, nor the monitoring effects differed significantly across the age groups after controlling for individual differences in associative recognition performance. Whole brain analyses did however identify three clusters outside of these regions where recollection effects were greater in the young than in the other age groups. Across-participant regression analyses indicated that the magnitude of hippocampal and medial prefrontal cortex recollection effects, and both of the prefrontal monitoring effects, correlated significantly with memory performance. None of these correlations were moderated by age. The findings suggest that the relationships between memory performance and functional activity in regions consistently implicated in successful recollection and retrieval monitoring are stable across much of the healthy adult lifespan. PMID:27155127

  16. 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

  17. 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

  18. 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.

  19. How do groups work? Age differences in performance and the social outcomes of peer collaboration.

    PubMed

    Leman, Patrick J

    2015-05-01

    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 awarded to the best performing individuals. Findings, both in terms of social outcomes and performance in the quiz, indicated that the 8-year olds viewed the benefits of group membership in terms of the opportunities to receive information from other members. The 13-year olds, in contrast, viewed group collaboration as a constructive process where success was connected with group cohesiveness.

  20. 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

  1. 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.

  2. Changes in whole-brain functional networks and memory performance in aging.

    PubMed

    Sala-Llonch, Roser; Junqué, Carme; Arenaza-Urquijo, Eider M; Vidal-Piñeiro, Dídac; Valls-Pedret, Cinta; Palacios, Eva M; Domènech, Sara; Salvà, Antoni; Bargalló, Nuria; Bartrés-Faz, David

    2014-10-01

    We used resting-functional magnetic resonance imaging data from 98 healthy older adults to analyze how local and global measures of functional brain connectivity are affected by age, and whether they are related to differences in memory performance. Whole-brain networks were created individually by parcellating the brain into 90 cerebral regions and obtaining pairwise connectivity. First, we studied age-associations in interregional connectivity and their relationship with the length of the connections. Aging was associated with less connectivity in the long-range connections of fronto-parietal and fronto-occipital systems and with higher connectivity of the short-range connections within frontal, parietal, and occipital lobes. We also used the graph theory to measure functional integration and segregation. The pattern of the overall age-related correlations presented positive correlations of average minimum path length (r = 0.380, p = 0.008) and of global clustering coefficients (r = 0.454, p < 0.001), leading to less integrated and more segregated global networks. Main correlations in clustering coefficients were located in the frontal and parietal lobes. Higher clustering coefficients of some areas were related to lower performance in verbal and visual memory functions. In conclusion, we found that older participants showed lower connectivity of long-range connections together with higher functional segregation of these same connections, which appeared to indicate a more local clustering of information processing. Higher local clustering in older participants was negatively related to memory performance.

  3. 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.

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

    PubMed Central

    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. PMID:24624114

  5. 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.

  6. The interaction of age, performance and hypnotics in the sleep of insomniacs.

    PubMed

    Bonnet, M H; Kramer, M

    1981-11-01

    Scant attention has been paid to the objective evaluation of insomnia as a function of age, particularly with reference to increased drug sensitivity and resulting loss in balance performance. Therefore, the electroencephalographic sleep and the balance-board performance of 10 young and 12 geriatric insomniacs were studied under baseline and hypnotic drug (ketazolam) conditions. In terms of objectively measured sleep, the geriatric insomniacs had worse sleep on every dimension except sleep latency and percentage of stage-2 sleep. These differences between aged and young insomniacs, however, were no greater than might be expected as a function of normal aging. Drug-age interactions indicated that ketazolam differentially increased sleep efficiency, decreased the percentage of REM sleep, and eliminated any learning improvement on the balance board in geriatric versus young insomniacs. The findings indicate that the geriatric subjects were more sensitive to the hypnotic drug, in that their sleep improved to a greater extent. However, an important loss in balance performance was also observed.

  7. 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.

  8. Spider silk aging: initial improvement in a high performance material followed by slow degradation.

    PubMed

    Agnarsson, Ingi; Boutry, Cecilia; Blackledge, Todd A

    2008-10-01

    Spider silk possesses a unique combination of high tensile strength and elasticity resulting in extraordinarily tough fibers, compared with the best synthetic materials. However, the potential application of spider silk and biomimetic fibers depends upon retention of their high performance under a variety of conditions. Here, we report on changes in the mechanical properties of dragline and capture silk fibers from several spider species over periods up to 4 years of benign aging. We find an improvement in mechanical performance of silk fibers during the first year of aging. Fibers rapidly decrease in diameter, suggesting an increase in structural alignment and organization of molecules. One-year old silk also is stiffer and has higher stress at yield than fresh silk, whereas breaking force, elasticity, and toughness either improve or are unaffected by early aging. However, 4-year old silk shows signs of degradation as the breaking load, elasticity, and toughness are all lower than in fresh silk. Aging, however, does not reduce the tensile strength of silk. These data suggest initially rapid reorganization and tighter packaging of molecules within the fiber, followed by longer-term decomposition. We hypothesize that possibly the breakdown of amino acids via emission of ammonia gas, as is seen in long-term aging of museum silkworm fabrics, may contribute. Degradation of spider silk under benign conditions may be a concern for efforts to construct and utilize biomimetic silk analogs. However, our findings suggest an initial improvement in mechanical performance and that even old spider silk still retains impressive mechanical performance. PMID:18626974

  9. 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.

  10. The effect of age on postural and cognitive task performance while using vibrotactile feedback

    PubMed Central

    Whitney, Susan L.; Loughlin, Patrick J.; Furman, Joseph M.; Redfern, Mark S.; Sienko, Kathleen H.; Sparto, Patrick J.

    2015-01-01

    Vibrotactile feedback (VTF) has been shown to improve balance performance in healthy people and people with vestibular disorders in a single-task experimental condition. It is unclear how age-related changes in balance affect the ability to use VTF and if there are different attentional requirements for old and young adults when using VTF. Twenty younger and 20 older subjects participated in this two-visit study to examine the effect of age, VTF, sensory condition, cognitive task, duration of time, and visit on postural and cognitive performance. Postural performance outcome measures included root mean square of center of pressure (COP) and trunk tilt, and cognitive performance was assessed using the reaction time (RT) from an auditory choice RT task. The results showed that compared with younger adults, older adults had an increase in COP in fixed platform conditions when using VTF, although they were able to reduce COP during sway-referenced platform conditions. Older adults also did not benefit fully from using VTF in their first session. The RTs for the secondary cognitive tasks increased significantly while using the VTF in both younger and older adults. Older adults had a larger increase compared with younger adults, suggesting that greater attentional demands were required in older adults when using VTF information. Future training protocols for VTF should take into consideration the effect of aging. PMID:25589585

  11. The influence of performance level, age and gender on pacing strategy during a 100-km ultramarathon.

    PubMed

    Renfree, Andrew; Crivoi do Carmo, Everton; Martin, Louise

    2016-01-01

    The aim of this study is to analyse the influence of performance level, age and gender on pacing during a 100-km ultramarathon. Results of a 100-km race incorporating the World Masters Championships were used to identify differences in relative speeds in each 10-km segment between participants finishing in the first, second, third and fourth quartiles of overall positions (Groups 1, 2, 3 and 4, respectively). Similar analyses were performed between the top and bottom 50% of finishers in each age category, as well as within male and female categories. Pacing varied between athletes achieving different absolute performance levels. Group 1 ran at significantly lower relative speeds than all other groups in the first three 10-km segments (all P < 0.01), and significantly higher relative speeds than Group 4 in the 6th and 10th (both P < 0.01), and Group 2 in the 8th (P = 0.04). Group 4 displayed significantly higher relative speeds than Group 2 and 3 in the first three segments (all P < 0.01). Overall strategies remained consistent across age categories, although a similar phenomenon was observed within each category whereby 'top' competitors displayed lower relative speeds than 'bottom' competitors in the early stages, but higher relative speeds in the later stages. Females showed lower relative starting speeds and higher finishing speeds than males. 'Top' and 'bottom' finishing males displayed differing strategies, but this was not the case within females. Although pacing remained consistent across age categories, it differed with level of performance within each, possibly suggesting strategies are anchored on direct competitors. Strategy differs between genders and differs depending on performance level achieved in males but not females. PMID:26034882

  12. Mechanisms Underlying Age- and Performance-related Differences in Working Memory

    PubMed Central

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

    2011-01-01

    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. PMID:20617886

  13. 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.

  14. 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

  15. 29 CFR 570.34 - Occupations that may be performed by minors 14 and 15 years of age.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Occupations that may be performed by minors 14 and 15 years... performed by minors 14 and 15 years of age. This subpart authorizes only the following occupations in which the employment of minors 14 and 15 years of age is permitted when performed for periods and...

  16. Influence of age and selected environmental factors on reproductive performance of canvasbacks

    USGS Publications Warehouse

    Serie, Jerome R.; Trauger, David L.; Austin, Jane E.

    1992-01-01

    Age, productivity, and other factors affecting breeding performance of canvasbacks (Aythya valisineria) are poorly understood. Consequently, we tested whether reproductive performance of female canvasbacks varied with age and selected environmental factors in southwestern Manitoba from 1974 to 1980. Neither clutch size, nest parasitism, nest success, nor the number of ducklings/brood varied with age. Return rates, nest initiation dates, renesting, and hen success were age-related. Return rates averaged 21% for second-year (SY) and 69% for after-second-year (ASY) females (58% for third-year and 79% for after-third-year females). Additionally, water conditions and spring temperatures influenced chronology of arrival, timing of nesting, and reproductive success. Nest initiation by birds of all ages was affected by minimum April temperatures. Clutch size was higher in nests initiated earlier. Interspecific nest parasitism did not affect clutch size, nest success, hen success, or hatching success. Nest success was lower in dry years (17%) than in moderately wet (54%) or wet (60%) years. Nests per female were highest during wet years. No nests of SY females were found in dry years. In years of moderate to good wetland conditions, females of all ages nested. Predation was the primary factor influencing nest success. Hen success averaged 58% over all years. The number of ducklings surviving 20 days averaged 4.7/brood. Because SY females have lower return rates and hen success than ASY females, especially during drier years, management to increase canvasback populations might best be directed to increasing first year recruitment (no. of females returning to breed) and to increasing overall breeding success by reducing predation and enhancing local habitat conditions during nesting.

  17. Effect of age on anthropometric and physical performance measures in professional baseball players.

    PubMed

    Mangine, Gerald T; Hoffman, Jay R; Fragala, Maren S; Vazquez, Jose; Krause, Matthew C; Gillett, Javair; Pichardo, Napoleon

    2013-02-01

    The purpose of this study was to investigate age-related changes in anthropometric and performance variables in professional baseball players. Baseball players (n = 1,157) from several professional baseball organizations were categorized into 7 cohorts based upon age. All adolescent athletes were categorized as age group 1 (AG1), whereas the next 5 groups (AG2-AG6) consisted of players 20-22, 23-25, 26-28, 29-31, and 31-34 years, respectively. The final group (AG7) comprised athletes ≥35 years. All performance assessments were part of the athlete's normal preseason training camp testing routine. Field assessments were used to analyze lower-body power, speed, agility, grip strength, and body composition. The players were heaviest between the ages of 29 and 31 (AG5), and their body mass in that age group was 10.1% (p = 0.004) greater than that of AG1. A 7.0% increase (p = 0.000) in lean body mass occurred between AG1 and AG5. No differences in 10-yd sprint times or agility were seen across any age group or position. A 2.0 seconds (p = 0.001) slower run time for the 300-yd shuttle was seen between AG4 and AG5 for all positions combined. Elevations in grip strength were seen at AG4 compared with AG1 (p = 0.001) and AG2 (p = 0.007) for all positions combined. No other differences were noted. Lower-body power was increased for all positions combined from AG1 to AG3 (p = 0.007). This pattern was similar to that observed in position players, but a 12.4% decrease (p = 0.024) in VJMP was seen between AG7 and AG5 in pitchers. Results of this study indicate that lower-body power is maintained in baseball players until the age of 29-31, whereas speed, agility, and grip strength are maintained in players able to play past the age of 35 years. Age-related differences observed in this study suggest that athletes focus on their strength and conditioning programs to extend the length of their professional careers.

  18. Age-related alterations in default mode network: impact on working memory performance.

    PubMed

    Sambataro, Fabio; Murty, Vishnu P; Callicott, Joseph H; Tan, Hao-Yang; Das, Saumitra; Weinberger, Daniel R; Mattay, Venkata S

    2010-05-01

    The default mode network (DMN) is a set of functionally connected brain regions which shows deactivation (task-induced deactivation, TID) during a cognitive task. Evidence shows an age-related decline in task-load-related modulation of the activity within the DMN during cognitive tasks. However, the effect of age on the functional coupling within the DMN and their relation to cognitive performance has hitherto been unexplored. Using functional magnetic resonance imaging, we investigated functional connectivity within the DMN in older and younger subjects during a working memory task with increasing task load. Older adults showed decreased connectivity and ability to suppress low frequency oscillations of the DMN. Additionally, the strength of the functional coupling of posterior cingulate (pCC) with medial prefrontal cortex (PFC) correlated positively with performance and was lower in older adults. pCC was also negatively coupled with task-related regions, namely the dorsolateral PFC and cingulate regions. Our results show that in addition to changes in canonical task-related brain regions, normal aging is also associated with alterations in the activity and connectivity of brain regions within the DMN. These changes may be a reflection of a deficit in cognitive control associated with advancing age that results in deficient resource allocation to the task at hand.

  19. Age effects on gray matter volume and attentional performance in Zen meditation.

    PubMed

    Pagnoni, Giuseppe; Cekic, Milos

    2007-10-01

    Zen meditation, a Buddhist practice centered on attentional and postural self-regulation, has been speculated to bring about beneficial long-term effects for the individual, ranging from stress reduction to improvement of cognitive function. In this study, we examined how the regular practice of meditation may affect the normal age-related decline of cerebral gray matter volume and attentional performance observed in healthy individuals. Voxel-based morphometry for MRI anatomical brain images and a computerized sustained attention task were employed in 13 regular practitioners of Zen meditation and 13 matched controls. While control subjects displayed the expected negative correlation of both gray matter volume and attentional performance with age, meditators did not show a significant correlation of either measure with age. The effect of meditation on gray matter volume was most prominent in the putamen, a structure strongly implicated in attentional processing. These findings suggest that the regular practice of meditation may have neuroprotective effects and reduce the cognitive decline associated with normal aging.

  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. Measuring the performance of electronic health records: a case study in residential aged care in Australia.

    PubMed

    Yu, Ping; Qian, Siyu; Yu, Hui; Lei, Jianbo

    2013-01-01

    Measuring the performance of electronic health records (EHR) is an important, yet un-resolved challenge. Various measurements have addressed different aspects of EHR success, yet a holistic, comprehensive measurement tool needs to be developed to capture the potential EHR success variables completely. A self-administered questionnaire survey instrument was developed based on the theoretical framework of the DeLone and McLean Information Systems Success Model. It measures nigh variables of EHR success: system quality, information quality, service quality, training, self efficacy, intention to use, use, user satisfaction and net benefits. The instrument was used to measure the performance of aged care EHR systems in three aged care organizations. The results suggest that the instrument was reliable. PMID:23920809

  4. 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. PMID:26282079

  5. 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

  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. Age differences in three facets of empathy: performance-based evidence.

    PubMed

    Richter, David; Kunzmann, Ute

    2011-03-01

    This study investigated age differences in cognitive and affective facets of empathy: the ability to perceive another's emotions accurately, the capacity to share another's emotions, and the ability to behaviorally express sympathy in an empathic episode. Participants, 80 younger (M(age) = 32 years) and 73 older (M(age) = 59 years) adults, viewed eight film clips, each portraying a younger or an older adult thinking-aloud about an emotionally engaging topic that was relevant to either younger adults or older adults. In comparison to their younger counterparts, older adults generally reported and expressed greater sympathy while observing the target persons; and they were better able to share the emotions of the target persons who talked about a topic that was relevant to older adults. Age-related deficits in the cognitive ability to accurately perceive another's emotions were only evident when the target person talked about a topic of little relevance to older adults. In sum, the present performance-based evidence speaks for multidirectional age differences in empathy.

  8. 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. PMID:26439783

  9. 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.

  10. 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,…

  11. The relationships between age, associative memory performance, and the neural correlates of successful associative memory encoding.

    PubMed

    de Chastelaine, Marianne; Mattson, Julia T; Wang, Tracy H; Donley, Brian E; Rugg, Michael D

    2016-06-01

    Using functional magnetic resonance imaging, subsequent memory effects (greater activity for later remembered than later forgotten study items) predictive of associative encoding were compared across samples of young, middle-aged, and older adults (total N = 136). During scanning, participants studied visually presented word pairs. In a later test phase, they discriminated between studied pairs, "rearranged" pairs (items studied on different trials), and new pairs. Subsequent memory effects were identified by contrasting activity elicited by study pairs that went on to be correctly judged intact or incorrectly judged rearranged. Effects in the hippocampus were age-invariant and positively correlated across participants with associative memory performance. Subsequent memory effects in the right inferior frontal gyrus (IFG) were greater in the older than the young group. In older participants only, both left and, in contrast to prior reports, right IFG subsequent memory effects correlated positively with memory performance. We suggest that the IFG is especially vulnerable to age-related decline in functional integrity and that the relationship between encoding-related activity in right IFG and memory performance depends on the experimental context. PMID:27143433

  12. Harmonizing Measures of Cognitive Performance Across International Surveys of Aging Using Item Response Theory

    PubMed Central

    Chan, Kitty S.; Gross, Alden L.; Pezzin, Liliana E.; Brandt, Jason; Kasper, Judith D.

    2016-01-01

    Objective To harmonize measures of cognitive performance using item response theory (IRT) across two international aging studies. Methods Data for persons ≥65 from the Health and Retirement Study (HRS, N=9,471) and the English Longitudinal Study of Aging (ELSA, N=5,444). Cognitive performance measures varied (HRS fielded 25, ELSA 13); 9 were in common. Measurement precision was examined for IRT scores based on: 1) common items; 2) common items adjusted for differential item functioning (DIF); 3) DIF-adjusted all items. Results Three common items (day of date, immediate word recall, and delayed word recall) demonstrated DIF by survey. Adding survey-specific items improved precision, but mainly for HRS respondents at lower cognitive levels. Discussion IRT offers a feasible strategy for harmonizing cognitive performance measures across other surveys and for other multi-item constructs of interest in studies of aging. Practical implications depend on sample distribution and the difficulty mix of in-common and survey-specific items. PMID:26526748

  13. Little evidence for links between memory complaints and memory performance in very old age: longitudinal analyses from the Berlin Aging Study.

    PubMed

    Pearman, Ann; Hertzog, Christopher; Gerstorf, Denis

    2014-12-01

    Cross-sectional and longitudinal relationships between memory complaint and memory performance were examined in a sample of old-old participants from the Berlin Aging Study (BASE; N = 504, ages 70 to 100, age M = 84.7 at study onset). Participants were measured 4 times over the course of 6 years. Similar to many previous studies, initial cross-sectional memory complaints were predicted by depression and neuroticism, but not memory performance. Subjective age also predicted memory complaint independent of other variables. Latent growth curve models based on age and time in the study revealed that memory complaints did not change in level with age or time, and manifested no reliable random effects (individual differences in change). These models also detected no significant relationship between changes in memory and either initial memory complaint or changes in memory complaint over age or over time. None of the covariates that predicted initial memory complaints were related to changes in memory complaints over time. An autoregressive latent variable model for memory complaints, consistent with a conceptualization of complaints as judgments constructed from beliefs and other influences in the moment, did detect a concurrent effect of memory on memory complaints at the third occasion, controlling on initial complaints. These results suggest that for the oldest-old, changes in memory complaints may not primarily reflect monitoring of actual age-related memory changes, but rather are affected by other variables, including age-based memory stereotypes, neuroticism, depression, and concerns about aging.

  14. Influence of memory strategies on memory test performance: a study in healthy and pathological aging.

    PubMed

    Yubero, R; Gil, P; Paul, N; Maestú, F

    2011-09-01

    The ability to generate memory strategies is a key factor in the performance of episodic memory tasks. Whether the ability to generate memory strategies exerts an influence in the performance of memory tests in the elderly population is still a matter of debate. Here we present results from an experimental memory task (Test of Memory Strategies, TMS), comprised of five lists of words starting from an incidental learning task, and four more lists which progressively gain in their external organization of the material, reducing the necessity of mobilizing complex memory strategies. TMS has been applied to four groups of elderly patients (amnestic Mild Cognitive Impairment - aMCI, multidomain (mMCI), and Vascular Cognitive Impairment - VCI and Depression) and a healthy aging group. In conditions with low organization of the material, the mMCI and VCI groups (both showing a greater executive function impairment) have shown lower performance. However, as the material was progressively organized, they improved their performance. The aMCI group showed similar performance to the control group at the lower level of external organization but did not improve performance in conditions with a high level of external organization. The mMCI and VCI groups showed lower performance on all TMS conditions compared with controls. Discriminant analysis revealed 90% sensitivity and specificity to differentiate between groups based on TMS conditions. These results indicate how executive functions influence performance on memory tasks in elderly subjects with different neuropsychological profiles.

  15. 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

    2016-01-01

    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. PMID:27213310

  16. 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.

  17. Variation in Football Players’ Sprint Test Performance Across Different Ages and Levels of Competition

    PubMed Central

    Abrantes, Catarina; Maçãs, Vitor; Sampaio, Jaime

    2004-01-01

    The purpose of this study was to compare sprint test performance performed by football players of different ages and levels of competition. One hundred and forty six Portuguese players from different teams completed the test (seven maximal sprints interspersed with 25 s active recovery). A 6 (level of competition: 1st national division, 2nd national division, 1st regional division, sub 16, sub 14, sub 12) 7 (sprint trial: sprint 1, sprint 2, sprint 3, sprint 4, sprint 5, sprint 6, sprint 7) repeated measures ANOVA was carried out on subjects sprint times. The main effect of level of competition was statistically significant, F(5, 140) = 106.28, p < 0.001. Subjects from 1st national division were significantly faster than subjects from 2nd national division; subjects from 1st regional division obtained similar performances when compared to sub 16 and sub 14 level; subjects from sub 12 level were the slowest. The main effect of sprint trial was also statistically significant, F (6, 840) = 7.37, p < 0.001. Mean sprint times from the first trial were significantly slower than mean sprint times from the second, third and fourth trial. Results from the fifth, sixth and seventh trials were slower, denoting a decrement in performance. The two main effects were qualified by a significant level of competition x sprint trial interaction, F (30, 840) = 9.47 p < 0.001, identifying markedly different performance profiles. Coaches should be aware that normative data regarding this test can play a very important role if used frequently and consistently during the whole season. Key Points Groups of different ages (Sub 16, Sub 14 and Sub 12) and groups of different training quality (1st and 2nd national divisions and 1st regional division) were clearly discriminated by sprint test performances. Professional players exhibited higher performances in sprint test. Fatigue effects were the strongest between 5th to the 7th sprint. PMID:24778553

  18. Age-Related Effects of Study Time Allocation on Memory Performance in a Verbal and a Spatial Task

    ERIC Educational Resources Information Center

    Krueger, Lacy E.

    2012-01-01

    Past studies have suggested that study time allocation partially mediates age relations on memory performance in a verbal task. To identify whether this applied to a different material modality, participants ages 20-87 completed a spatial task in addition to a traditional verbal task. In both the verbal and the spatial task, increased age was…

  19. Characteristics influencing changes in aerobic performance of children aged 7-9.

    PubMed

    Faludi, J; Farkas, A; Zsidegh, M; Petrekanits, M; Pavlik, G

    1999-01-01

    Interpretation of the actual level of aerobic endurance in a growing child is difficult. Endurance capacity per se is influenced by a number of factors, e.g. by genetic endowment, developmental rate, body composition and habitual physical activity. The respective effects of these factors cannot be distinctly separated from one another, so their particular role is not clearly definable in the various age periods. The aim of our investigation was to define the actual level of aerobic endurance performance in children aged 7-9, and to analyse the relevant factors that may affect this kind of performance according to the different level of sport activities. Two primary school classes (N=42) were selected for the experiment. Both groups had physical education classes every day (five times a week). One group (AG, N=31) consisted of children taking part in regular sport courses at least twice a week (e.g. basket ball, karate, triathlon swimming and gymnastics), as well, the other group (NAG, N=11) served as comparison group. Aerobic performance was estimated by measuring cardiorespiratory response during a Jaeger treadmill run using a "vita maxima" (all-out) testing protocol. The subjects were measured in the Laboratory for Spiroergometry of the Hungarian University of Physical Education twice, in 1997 and 1998. Body composition was assessed by the Drinkwater-Ross [4] body mass fractionation technique. Robustness of the body was described by using the plastic index (PLX) of Conrad's growth type [2], morphological age (MORF AGE) was estimated by using the method of Mészáros and Mohácsi [5]. Exercise performance was studied in the laboratory by using a Jaeger 6000 LE model treadmill and a Jaeger mu-DATASPIR model gas analyser. The functional status of the subjects' cardiopulmonary system was estimated by spiroergometric parameters and total mechanical work (WORK). The AG group had a better endurance performance in 1998 than that of non-athletic group. A factor analytic

  20. Effect of age at feedlot entry on performance and carcass characteristics of bulls and steers.

    PubMed

    Schoonmaker, J P; Loerch, S C; Fluharty, F L; Zerby, H N; Turner, T B

    2002-09-01

    Seventy Angus x Simmental calves (BW = 166.3 +/- 4.2 kg) were used in a 3 x 2 factorial arrangement to determine the effect of age at feedlot entry and castration on growth, performance, and carcass characteristics. At 82 d of age, steers were castrated. Calves were placed in the feedlot at 111 (early-weaned), 202, or 371 (yearling) d of age. Steers were implanted with Synovex-S followed 93 d later with Revalor-S. Calves were harvested on an individual basis when fat thickness was estimated to be 1.27 cm. During the feedlot phase, yearlings gained faster (P < 0.01) than calves placed in the feedlot at 202 or 111 d of age (1.88, 1.68, and 1.62 kg/d, respectively); however, from 111 d of age until harvest, ADG was greatest for early-weaned calves, intermediate for cattle placed in the feedlot at 202 d of age, and lowest for yearlings (1.62, 1.47, and 1.21 kg/d, respectively; P < 0.01). Early-weaned calves spent the most days in the feedlot, followed by calves placed in the feedlot at 202 d of age; yearlings spent the fewest days in the feedlot (221, 190, and 163 d, respectively; P < 0.01). Total DMI when in the feedlot was similar (P = 0.22) among age groups; however, daily DMI was lowest for early-weaned calves, intermediate for calves placed in the feedlot at 202 d of age, and the highest for yearlings (7.1, 8.1, 10.5 kg/ d, respectively; P < 0.01). Early-weaned calves were the most efficient, followed by calves placed in the feedlot at 202 d of age; yearlings were the least efficient (227, 207, 180 g gain/kg feed, respectively; P < 0.01). Weight at harvest (682, 582, 517 kg, respectively; P < 0.01) and hot carcass weight (413, 358, 314 kg, respectively; P < 0.01) were greatest for yearlings, intermediate for cattle placed in the feedlot at 202 d of age, and lowest for early-weaned calves. Early-weaned calves had the smallest longissimus area, followed by calves placed in the feed-lot at 202 d of age; yearlings had the largest longissimus area (77, 86, 88 cm2

  1. 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.

  2. Poult performance as influenced by age of dam, genetic line, and dietary vitamin E.

    PubMed

    Siegel, P B; Blair, M; Gross, W B; Meldrum, B; Larsen, C; Boa-Amponsem, K; Emmerson, D A

    2006-05-01

    An experiment was conducted to measure the effects of age of dam, genetic line, and dietary levels of vitamin E on growth and immunocompetence of poults. Age of dam was defined as younger (in early egg production) and older (past peak production); line consisted of a commercial sire and dam line; and dietary vitamin E was supplemented into the diet at 10 and 300 IU/kg of feed. Traits measured included body, liver, gizzard, and yolk sac weights at hatch; BW and feed conversion to 9, 28, and 42 d; response to SRBC, Phaseolus vulgaris agglutinin-P, and Escherichia coli administered at 28 d of age; and response to a cold stress on d 5 posthatch. Differences among genetic lines were evident with growth greater for poults from the sire than from the dam line. Performance of poults from older dams was generally superior to that of poults from younger dams. The higher level of vitamin E resulted in a greater than 7-fold increase in blood plasma vitamin E and reduced mortality. There were interactions among the main effects in which the fitness of poults from younger dams was enhanced by the higher level of vitamin E and the effect of breeder age differed among genetic lines.

  3. 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

  4. 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.

  5. Maternal aging affects life performance of progeny in a Holstein dairy cow model.

    PubMed

    Astiz, S; Gonzalez-Bulnes, A; Sebastian, F; Fargas, O; Cano, I; Cuesta, P

    2014-10-01

    The development and life performance of 404 high-producing Holstein dairy cows was studied from birth onwards and during two lactations. The management, environment and parental genetics of the cows were known in detail. Cluster analysis identified four performance 'types': high-yielding (HY) cows and persistently high-yielding (PHY) cows, which accounted for 33% of the animals; medium-yielding (MY) cows, 41%; and low-yielding (LY) cows, 26%. Prenatal determinants of the life performance of the progeny were analyzed. Developmental and environmental factors were excluded as determinants of performance (including birth weight, level of passive immunity transfer, growth rate, age at first parturition and reproductive efficiency). Life performance did show minor seasonal effects, with more HY cows but less PHY being born during the cold season (90.1% in HY; 58.3% in PHY v. 81.5%). Instead, the single most important factor influencing life performance of daughters was maternal age. HY cows were born from the youngest mothers (1.89±1.14 parturitions, 3.12±1.42-year old), whereas LY cows were born from the oldest (2.72±1.80 parturitions, 3.97±2.01-year old; P<0.001). Life performance of the dams did not differ among clusters. In addition, metabolic parameters (fat and protein yield) were found to correlate significantly with yields between the first and second lactations (milk yield: r=0.357; fat yield: r=0.211; protein yield: r=0.277; P<0.0001), suggesting the influence of the individual. These results suggest that under optimal health, nutritional and environmental conditions, maternal aging is an important determinant of the life performance of progeny and argue for the need to identify conditions that contribute to health and disease in progeny according to the Developmental Origin of Health and Disease or DOHaD concept. Our findings may help the development of novel management guidelines for dairy farms.

  6. Maternal aging affects life performance of progeny in a Holstein dairy cow model.

    PubMed

    Astiz, S; Gonzalez-Bulnes, A; Sebastian, F; Fargas, O; Cano, I; Cuesta, P

    2014-10-01

    The development and life performance of 404 high-producing Holstein dairy cows was studied from birth onwards and during two lactations. The management, environment and parental genetics of the cows were known in detail. Cluster analysis identified four performance 'types': high-yielding (HY) cows and persistently high-yielding (PHY) cows, which accounted for 33% of the animals; medium-yielding (MY) cows, 41%; and low-yielding (LY) cows, 26%. Prenatal determinants of the life performance of the progeny were analyzed. Developmental and environmental factors were excluded as determinants of performance (including birth weight, level of passive immunity transfer, growth rate, age at first parturition and reproductive efficiency). Life performance did show minor seasonal effects, with more HY cows but less PHY being born during the cold season (90.1% in HY; 58.3% in PHY v. 81.5%). Instead, the single most important factor influencing life performance of daughters was maternal age. HY cows were born from the youngest mothers (1.89±1.14 parturitions, 3.12±1.42-year old), whereas LY cows were born from the oldest (2.72±1.80 parturitions, 3.97±2.01-year old; P<0.001). Life performance of the dams did not differ among clusters. In addition, metabolic parameters (fat and protein yield) were found to correlate significantly with yields between the first and second lactations (milk yield: r=0.357; fat yield: r=0.211; protein yield: r=0.277; P<0.0001), suggesting the influence of the individual. These results suggest that under optimal health, nutritional and environmental conditions, maternal aging is an important determinant of the life performance of progeny and argue for the need to identify conditions that contribute to health and disease in progeny according to the Developmental Origin of Health and Disease or DOHaD concept. Our findings may help the development of novel management guidelines for dairy farms. PMID:25084160

  7. Impact of Pretreatment and Aging on the Iodine Capture Performance of Silver-Exchanged Mordenite - 12314

    SciTech Connect

    Jubin, R.T.; Ramey, D.W.; Spencer, B.B.; Anderson, K.K.; Robinson, S.M.

    2012-07-01

    Volatile gas emissions from a nuclear fuel recycle facility in the United States are governed by several key regulations, including 10 CFR 20, 40 CFR 61, and 40 CFR 190. Under 40 CFR 190, the total quantity of iodine that may be released to the environment from the entire fuel cycle is limited to 5 millicuries of I-129 per gigawatt-year of electrical energy produced by the fuel cycle. With a reasonable engineering margin, an iodine decontamination factor (DF) of approximately 1000 will be required for the complete fuel cycle. Off-gas treatment in a fuel reprocessing plant must address several gas streams containing iodine, among a number of volatile radionuclides. Past research and developmental activities identified silver-exchanged mordenite (AgZ) as a very promising sorbent based on its acid resistance, relatively high iodine and methyl iodide capacity, and high achievable DF. Recent studies at ORNL have focused on the impacts of long-term exposure to simulated off-gas streams (aging) and pretreatment on the iodine adsorption performance of hydrogen-reduced silver-exchanged mordenite (Ag{sup 0}Z). Experiments were conducted to determine the effects of long-term exposure to both dry and moist air on the iodine sorption capacity of Ag{sup 0}Z. The data indicates that aging reduces the capacity of Ag{sup 0}Z, which must be accounted for to prevent degradation of DF. Because of its high acid resistance, a AgZ sorbent has been selected specifically for application in treating off-gas streams containing iodine. While extensive tests have been conducted in the United States on a form of this sorbent, the specific material previously tested is no longer commercially available and similar materials are currently being evaluated. As part of this evaluation, tests were conducted to determine the iodine sorption properties of this replacement media and the effects of long-term (up to 6 months) exposure to simulated off-gas streams. The ultimate goal is to develop an

  8. Athletic performance and birth month: is the relative age effect more than just selection bias?

    PubMed

    Sandercock, G R H; Ogunleye, A A; Parry, D A; Cohen, D D; Taylor, M J D; Voss, C

    2014-11-01

    The aim of this study was to determine if month of birth affects performance in 3 tests of physical function in children and adolescents. We measured cardiorespiratory fitness, handgrip strength and lower-body power expressed them relative to (whole year) age then compared scores between calendar year birth-months. We also expressed test performance as the likelihood of achieving criterion-referenced fitness standards. There were significant main effects of birth-month for cardiorespiratory fitness (F=4.54, p<0.001), strength (F=6.81, p<0.001) and power (F=3.67, p<0.001). Children born in November were fitter and more powerful than those born at other times, particularly the summer months (April, May and June). October-born children were stronger than those born in all months except September and November. This relationship was evident despite controlling for decimal age and despite no significant inter-month differences in anthropometric characteristics.There is a clear physical advantage for those born in the autumn and this may explain some of the bias in sports selection attributed to the relative age effect, particularly when the British school-year (September) cut-off is used.

  9. Quantification of the relative age effect in three indices of physical performance.

    PubMed

    Sandercock, Gavin R H; Taylor, Matthew J; Voss, Christine; Ogunleye, Ayodele A; Cohen, Daniel D; Parry, David A

    2013-12-01

    The relative age effect (RAE) describes the relationship between an individual's birth month and their level of attainment in sports. There is a clustering of birth dates just after the cutoff used for selection in age-grouped sports, and it is hypothesized that such relatively older sportspeople may enjoy maturational and physical advantages over their younger peers. There is, however, little empirical evidence of any such advantage. This study investigated whether schoolchildren's physical performance differed according to which quarter of the school year they were born in. Mass, stature, body mass index, cardiorespiratory fitness, strength, and power were measured in 10 to 16 year olds (n = 8,550, 53% male). We expressed test performance as age- and sex-specific z-scores based on reference data with age rounded down to the nearest whole year and also as units normalized for body mass. We then compared these values between yearly birth quarters. There were no significant main effects for differences in anthropometric measures in either sex. Girls born in the first quarter of the school year were significantly stronger than those born at other times when handgrip was expressed as a z-score. As z-scores, all measures were significantly higher in boys born in either the first or second yearly quarters. Relative to body mass, cardiorespiratory fitness was higher in boys born in the first quarter and power was higher in those born in the second quarter. The RAE does not appear to significantly affect girls' performance test scores when they are expressed as z-score or relative to body mass. Boys born in the first and second quarters of the year had a significant physical advantage over their relatively younger peers. These findings have practical bearing if coaches use fitness tests for talent identification and team selection. Categorizing test performance based on rounded down values of whole-year age may disadvantage children born later in the selection year. These

  10. Quantification of the relative age effect in three indices of physical performance.

    PubMed

    Sandercock, Gavin R H; Taylor, Matthew J; Voss, Christine; Ogunleye, Ayodele A; Cohen, Daniel D; Parry, David A

    2013-12-01

    The relative age effect (RAE) describes the relationship between an individual's birth month and their level of attainment in sports. There is a clustering of birth dates just after the cutoff used for selection in age-grouped sports, and it is hypothesized that such relatively older sportspeople may enjoy maturational and physical advantages over their younger peers. There is, however, little empirical evidence of any such advantage. This study investigated whether schoolchildren's physical performance differed according to which quarter of the school year they were born in. Mass, stature, body mass index, cardiorespiratory fitness, strength, and power were measured in 10 to 16 year olds (n = 8,550, 53% male). We expressed test performance as age- and sex-specific z-scores based on reference data with age rounded down to the nearest whole year and also as units normalized for body mass. We then compared these values between yearly birth quarters. There were no significant main effects for differences in anthropometric measures in either sex. Girls born in the first quarter of the school year were significantly stronger than those born at other times when handgrip was expressed as a z-score. As z-scores, all measures were significantly higher in boys born in either the first or second yearly quarters. Relative to body mass, cardiorespiratory fitness was higher in boys born in the first quarter and power was higher in those born in the second quarter. The RAE does not appear to significantly affect girls' performance test scores when they are expressed as z-score or relative to body mass. Boys born in the first and second quarters of the year had a significant physical advantage over their relatively younger peers. These findings have practical bearing if coaches use fitness tests for talent identification and team selection. Categorizing test performance based on rounded down values of whole-year age may disadvantage children born later in the selection year. These

  11. Erectile Dysfunction, Vascular Risk, and Cognitive Performance in Late Middle Age

    PubMed Central

    Moore, Caitlin S.; Grant, Michael D.; Zink, Tyler A.; Panizzon, Matthew S.; Franz, Carol E.; Logue, Mark W.; Hauger, Richard L.; Kremen, William S.; Lyons, Michael J.

    2016-01-01

    Vascular disease is the most common etiology of erectile dysfunction (ED). Men with ED are at a 65% increased relative risk of developing coronary heart disease and a 43% increased risk of stroke within 10 years. Vascular disease is associated with cognitive impairment; ED—an overt manifestation of vascular dysfunction—could also signal early compromised cognition. We sought to determine whether cognitive differences existed between men with ED and healthy peers. Our sample consisted of 651 men (ages 51–60 years) from the Vietnam Era Twin Study of Aging. ED was associated with poorer cognitive performance, particularly on attention–executive–psychomotor speed tasks. ED remained significantly associated with cognition after inclusion of other cardiovascular risk factors (including hypertension, high cholesterol, body mass index, and smoking). These findings underscore the importance of further study of ED as a predictor of cognitive and cardiovascular health. PMID:24660805

  12. Run performance of middle-aged and young adult runners in the heat.

    PubMed

    de Paula Viveiros, J; Amorim, F T; Alves, M N M; Passos, R L F; Meyer, F

    2012-03-01

    The aging process may impair exercise tolerance in the heat. It is not clear whether this impairment is partly due to a reduction in aerobic capacity. To compare the exercise performance and thermoregulatory responses of middle-aged and young adults with similar aerobic capacities and training statuses, 7 middle-aged (54±2 years; 58±4 ml·kg - 1·min - 1) and 7 young (28±1 years; 61±5 ml·kg - 1·min - 1) male competitive endurance runners underwent 2 10-km self-paced and 2 fixed-workload (90% of race speed) runs until fatigue on a treadmill in hot (40°C) and moderate (20°C) environments on separate days. The runners' total time, average speed, rectal temperature, heat storage rate, physiological strain index, sweat rate, sweat sensitivity, number of heat-activated sweat glands and sweat rate per sweat gland were measured or calculated. Body fat, body surface area, body surface area per body mass, training volume and VO2max were similar between the 2 groups. No differences were observed in total time (59±3; 49±3; 27±2; 54±5 min in the middle-aged and 60±2; 49±3; 27±2; 51±4 min in the young group), average speed, rectal temperature, heat storage rate, physiological strain index, sweat rate (17±7; 15±3; 23±7; 13±2 g.m - 2.min - 1 in the middle-aged and 20±5; 14±4; 22±5; 15±4 g.m - 2.min - 1 in the young group) or sweat sensitivity between age groups (p>0.05) in any trial. The number of heat-activated sweat glands (88±14; 80±18; 90±16; 66±14 cm - 2 in the middle-aged and 43±10; 32±10; 37±11; 31±11 cm - 2 in the young group) was higher, and the sweat rate per sweat gland was smaller, in the middle-aged than the young group (p<0.05) in all of the trials. We conclude that running performance and body thermoregulation are similar between young and middle-aged runners with similar aerobic capacities and training statuses under hot and moderate conditions in self-paced and fixed-intensity runs. The

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

    PubMed Central

    Takeshima, N; Tanaka, K

    1995-01-01

    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. PMID:7788211

  14. AGING PERFORMANCE OF VITON GLT O-RINGS IN RADIOACTIVE MATERIAL PACKAGES

    SciTech Connect

    Skidmore, E; Kerry Dunn, K; Elizabeth Hoffman, E; Elise Fox, E; Kathryn Counts, K

    2007-05-07

    Radioactive material packages used for transportation of plutonium-bearing materials often contain multiple O-ring seals for containment. Packages such as the Model 9975 are also being used for interim storage of Pu-bearing materials at the Savannah River Site (SRS). One of the seal materials used in such packages is Viton{reg_sign} GLT fluoroelastomer. The aging behavior of containment vessel O-rings based on Viton{reg_sign} GLT at long-term containment term storage conditions is being characterized to assess its performance in such applications. This paper summarizes the program and test results to date.

  15. The Effect of Performing Preoperative Preparation Program on School Age Children's Anxiety

    PubMed Central

    Vaezzadeh, Nazanin; Douki, Zahra Esmaeeli; Hadipour, Abbas; Osia, Soheil; Shahmohammadi, Soheila; Sadeghi, Roghieh

    2011-01-01

    Objective The purpose of this study was to examine effects of performing preoperative preparation program on children's anxiety. Methods This study was performed in Amirkola Pediatrics Hospital, Mazandaran. A randomized controlled trail was performed on 122 children (7–12 years of age) admitted for elective surgery during 15 months. The researcher randomly assigned eligible participants in to the experimental and control groups, after pre-test baseline measurement had been taken. Analyzing was performed through independent t-test and χ2 test. P<0.005 was considered statistically significant. The experimental group received therapeutic play and the control group received routine preoperative information preparation. Findings The mean and standard deviation of the state anxiety scores of children in experimental and control groups before intervention were 35.52±6.99 and 34.98±6.78, after intervention 31.44±5.87 and 38.31±7.44 respectively. The state anxiety score was lower significantly in the experimental group prior to preoperative surgery than in the control group (P=0.000). Conclusion Performing preoperative program with using therapeutic play intervention is effective for preparing children before surgery and decreases their anxiety. PMID:23056832

  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 influence of age and mild cognitive impairment on associative memory performance and underlying brain networks.

    PubMed

    Oedekoven, Christiane S H; Jansen, Andreas; Keidel, James L; Kircher, Tilo; Leube, Dirk

    2015-12-01

    Associative memory is essential to everyday activities, such as the binding of faces and corresponding names to form single bits of information. However, this ability often becomes impaired with increasing age. The most important neural substrate of associative memory is the hippocampus, a structure crucially implicated in the pathogenesis of Alzheimer's disease (AD). The main aim of this study was to compare neural correlates of associative memory in healthy aging and mild cognitive impairment (MCI), an at-risk state for AD. We used fMRI to investigate differences in brain activation and connectivity between young controls (n = 20), elderly controls (n = 32) and MCI patients (n = 21) during associative memory retrieval. We observed lower hippocampal activation in MCI patients than control groups during a face-name recognition task, and the magnitude of this decrement was correlated with lower associative memory performance. Further, increased activation in precentral regions in all older adults indicated a stronger involvement of the task positive network (TPN) with age. Finally, functional connectivity analysis revealed a stronger link of hippocampal and striatal components in older adults in comparison to young controls, regardless of memory impairment. In elderly controls, this went hand-in-hand with a stronger activation of striatal areas. Increased TPN activation may be linked to greater reliance on cognitive control in both older groups, while increased functional connectivity between the hippocampus and the striatum may suggest dedifferentiation, especially in elderly controls.

  18. Thermal manipulations during broiler incubation alter performance of broilers to 70 days of age.

    PubMed

    Piestun, Y; Druyan, S; Brake, J; Yahav, S

    2013-05-01

    Recent decades have seen significant progress in the genetic selection of fast-growing broiler chickens. Whereas in many countries the average marketing age is 5 to 6 wk, the US, French, and other markets demand heavier broilers (~4 kg) that require a longer posthatching growing period. With greater age and greater BW, the ability to cope with hot weather conditions deteriorates, which can result in increased economic losses during periods of hot weather. Recent studies have demonstrated a long-lasting effect of intermittent thermal manipulation (TM) during embryogenesis, when it was applied for 12 h/d between embryonic (E) days E7 and E16, which was shown by improved thermotolerance during acute posthatching heat stress as well as improved feed conversion ratio (FCR) and breast muscle yield. The present study was designed to elucidate the effect of TM during embryogenesis on Cobb 500 broiler performance up to 70 d of age. Hatchability and male BW were not affected by TM, but TM females demonstrated a lower (P = 0.024) BW during the entire 70-d posthatching study. However, following embryonic TM, both sexes exhibited lower (P = 0.028 and P = 0.018 for males and females, respectively) feed intake and body temperature accompanied by improved FCR and greater breast muscle weight. In light of the present and previous studies, it was concluded that intermittent TM during broiler embryonic development had a long-lasting effect on energy balance that led to improved FCR and breast muscle yield. PMID:23571323

  19. 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. PMID:21987915

  20. 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.

  1. 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

  2. Effect of cattle age, forage level, and corn processing on diet digestibility and feedlot performance.

    PubMed

    Gorocica-Buenfil, M A; Loerch, S C

    2005-03-01

    Three experiments were conducted to determine the effects of cattle age and dietary forage level on the utilization of corn fed whole or ground to feedlot cattle. In Exp. 1, 16 steers were used to investigate the effects of cattle age and corn processing on diet digestibility. Two cattle age categories were evaluated (weanling [254 +/- 20 kg BW] and yearling [477 +/- 29 kg BW]; eight steers per group), and corn was fed either ground or whole to each cattle age category. Cattle age and corn processing did not affect (P > 0.10) diet digestibility of DM, OM, starch, CP, NDF or ADF, and no interactions (P > 0.10) between these two factors were detected. In Exp. 2, the effects of forage level and corn processing on feedlot performance and carcass characteristics were evaluated. One hundred eighty steers (310 +/- 40 kg BW) were allotted to 24 pens, and were fed one of the following diets: high-forage (18.2% corn silage) cracked corn (HFCC); high-forage shifting corn (whole corn for the first half of the trial, then cracked corn until harvest; HFSC); high-forage whole corn (HFWC); low-forage (5.2% corn silage) cracked corn (LFCC); low-forage shifting corn (LFSC); and low-forage whole corn (LFWC). For the high-forage diets, steers fed cracked corn had 7% greater DMI than those fed whole corn, whereas for the low-forage diets, grain processing did not affect DMI (interaction; P = 0.02). No interactions (P > 0.10) between forage level and corn processing were found for ADG and G:F. Total trial ADG and G:F, and percentage of carcasses grading USDA Choice, and carcass yield grade were not affected (P > 0.10) by corn processing. Cattle with fewer days on feed grew faster and more efficiently when cracked corn was fed, whereas cattle with longer days on feed had greater ADG and G:F when corn was fed whole (interaction; P < 0.10). In Exp. 3, the effects of forage level and corn processing on diet digestibility were evaluated. The high-forage cracked corn, high-forage whole corn

  3. 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

  4. 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.

  5. 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

  6. Insulin Resistance, Brain Atrophy, and Cognitive Performance in Late Middle–Aged Adults

    PubMed Central

    Willette, Auriel A.; Xu, Guofan; Johnson, Sterling C.; Birdsill, Alex C.; Jonaitis, Erin M.; Sager, Mark A.; Hermann, Bruce P.; La Rue, Asenath; Asthana, Sanjay; Bendlin, Barbara B.

    2013-01-01

    OBJECTIVE Insulin resistance dysregulates glucose uptake and other functions in brain areas affected by Alzheimer disease. Insulin resistance may play a role in Alzheimer disease etiopathogenesis. This longitudinal study examined whether insulin resistance among late middle–aged, cognitively healthy individuals was associated with 1) less gray matter in Alzheimer disease–sensitive brain regions and 2) worse cognitive performance. RESEARCH DESIGN AND METHODS Homeostasis model assessment of insulin resistance, gray matter volume, and the Rey Auditory Verbal Learning Test (RAVLT) were acquired in 372 participants at baseline and a consecutive subset of 121 individuals ~4 years later. Voxel-based morphometry and tensor-based morphometry were used, respectively, to test the association of insulin resistance with baseline brain volume and progressive gray matter atrophy. RESULTS Higher insulin resistance predicted less gray matter at baseline and 4 years later in medial temporal lobe, prefrontal cortices, precuneus, and other parietal gyri. A region-of-interest analysis, independent of the voxel-wise analyses, confirmed that higher insulin resistance was related to medial temporal lobe atrophy. Atrophy itself corresponded to cognitive deficits in the RAVLT. Temporal lobe atrophy that was predicted by higher insulin resistance significantly mediated worse RAVLT encoding performance. CONCLUSIONS These results suggest that insulin resistance in an asymptomatic, late middle–aged cohort is associated with progressive atrophy in regions affected by early Alzheimer disease. Insulin resistance may also affect the ability to encode episodic information by negatively influencing gray matter volume in medial temporal lobe. PMID:23069842

  7. Effect of postural angle on back muscle activities in aging female workers performing computer tasks.

    PubMed

    Kamil, Nabilla Sofia Mohd; Dawal, Siti Zawiah Md

    2015-06-01

    [Purpose] This study investigated the effects of postural angle on back muscle activity during a computer task in aging women. [Subjects] Seventeen women ≥50 years old participated. [Methods] The participants were instructed to perform computer-related tasks for 20 minutes on a workstation that simulated typical office working conditions. Back posture was measured from the measured trunk and pelvic angles. Electromyography activities were recorded simultaneously from the cervical erector spinae, longissimus, and multifidus muscles. [Results] The lowest mean percentages of maximum voluntary contraction for the cervical erector spinae and longissimus muscles were obtained when the upper trunk and pelvic angles were between 0° to -5° from the sagittal plane. The back muscle activities increased as the upper trunk and pelvic angles exceeded 0°. Statistical analysis showed significant correlations between upper trunk angle and cervical erector spinae and longissimus muscle activities. Similarly, pelvic angle was significantly correlated with cervical erector spinae and multifidus muscle activities. [Conclusion] A neutral back posture minimizes muscle activities in aging women performing computer tasks.

  8. Voluntary exercise impairs initial delayed spatial alternation performance in estradiol treated ovariectomized middle-aged rats.

    PubMed

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

    2013-09-01

    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.

  9. 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

  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. PMID:26060999

  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. Dual reproductive cost of aging in male medflies: dramatic decrease in mating competitiveness and gradual reduction in mating performance

    PubMed Central

    Papanastasiou, Stella A.; Diamantidis, Alexandros D.; Nakas, Christos T.; Carey, James R.; Papadopoulos, Nikos T.

    2011-01-01

    Although age-based effects on the reproductive success of males have been reported in several animal taxa the cost of aging on male mating success in lekking species has not been fully explored. We used the Mediterranean fruit fly, a lekking species, to investigate possible cost of aging on male reproductive success. We performed no choice and choice mating tests to test the hypothesis that aging does not affect the mating performance (mating success in conditions lacking competition) or the mating competitiveness (mating success against younger rivals) of males. The mating probability of older males decreased significantly when competing with younger males. Aging gradually reduced the mating performance of males but older males were still accepted as mating partners in conditions lacking competition. Therefore, older males are capable of performing the complete repertoire of sexual performance but fail to be chosen by females in the presence of young rivals. Older males achieved shorter copulations than younger ones, and female readiness to mate was negatively affected by male age. Older and younger males transferred similar amount of spermatozoids to female spermathecae. Females stored spermatozoids asymmetrically in the two spermathecae regardless the age of their mating partner. Aging positively affected the amount of spermatozoids in testes of both mated and non mated males. No significant differences were observed on the amount of spermatozoids between mated and non mated males. PMID:21801728

  13. Identifying the limitations for growth in low performing piglets from birth until 10 weeks of age.

    PubMed

    Paredes, S P; Jansman, A J M; Verstegen, M W A; den Hartog, L A; van Hees, H M J; Bolhuis, J E; van Kempen, T A T G; Gerrits, W J J

    2014-06-01

    The evolution of hyper-prolific pig breeds has led to a higher within-litter variation in birth weight and in BW gain during the nursery phase. Based on an algorithm developed in previous research, two populations from a pool of 368 clinically healthy piglets at 6 weeks of age were selected: a low (LP) and a high (HP) performing population and their development was monitored until the end of the nursery phase (10 weeks of age). To understand the cause of the variation in growth between these populations we characterized the LP and HP piglets in terms of body morphology, behaviour, voluntary feed intake, BW gain, and apparent total tract and ileal nutrient digestibility. Piglets were housed individually and were fed a highly digestible diet. At selection, 6 weeks of age, the BW of LP and HP piglets were 6.8±0.1 and 12.2±0.1 kg, respectively. Compared with the LP piglets the HP piglets grew faster (203 g/day), ate more (275 g/day) from 6 to 10 weeks of age and were heavier at 10 weeks (30.0 v. 18.8 kg, all P<0.01). Yet, the differences in average daily gain and average daily feed intake disappeared when compared per kg BW0.75. Assuming similar maintenance requirements per kg BW0.75 the efficiency of feed utilization above maintenance was 0.1 g/g lower for the LP piglets (P=0.09).The gain : feed ratio was similar for both groups. LP piglets tended to take more time to touch a novel object (P=0.10), and spent more time eating (P<0.05). At 10 weeks, LP piglets had a higher body length and head circumference relative to BW (P<0.01). Relative to BW, LP had a 21% higher small intestine weight; 36% longer length, and relative to average FI, the small intestinal weight was 4 g/kg higher (both P=<0.01). Apparent total tract and ileal dry matter, N and gross energy digestibility were similar between groups (P>0.10). We concluded that the low performance of the LP piglets was due to their inability to engage compensatory gain or compensatory feed intake as efficiency of

  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 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.

  15. 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

  16. 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. PMID:27616991

  17. 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.

  18. 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

  19. Age and temperature related changes in behavioral and physiological performance in the Peromyscus leucopus mouse.

    PubMed

    Duffy, P H; Feuers, R J; Pipkin, J L; Turturro, A; Hart, R W

    1997-04-01

    Age-related and ambient temperature-related changes in motor activity, body temperature, body weight (b.w.), and food consumption were studied in the long-lived Peromyscus leucopus mouse at environmental temperatures of 29 and 21 degrees C. Major changes in physiological performance were observed between the young (6 months) and old (60-72 month) age groups. The number of daily activity episodes, and total activity output was significantly lower in old mice. Maximum, average and minimum daily body temperature was lower in the old mice and a significant ambient temperature-by-age interaction was found. Maximum, minimum, and average daily b.w. was higher in old mice. Motor activity was evenly distributed over the active (night) phase in young mice but in old mice activity was significantly greater in the late night partition of the active cycle than in the early night partition. Both groups were significantly more active at night than during the day. Most of the food consumption in both groups occurred at night, but young mice consumed significantly more during the late night partition than the early night partition, and the consumption rates for old mice were not significantly different between early and late night partitions. The percentage of activity episodes involved with food consumption in both groups was significantly higher during the night partition, but the percentage during the early night partition was significantly higher in old mice than in young mice. Significant episodes of circadian torpor occurred in a high percentage of old mice at 06:00, on consecutive days, at both environmental temperatures, but young mice expressed no evidence of torpor.

  20. Effects of Age, Sex, and Neuropsychological Performance on Financial Decision-Making

    PubMed Central

    Shivapour, Sara K.; Nguyen, Christopher M.; Cole, Catherine A.; Denburg, Natalie L.

    2012-01-01

    The capacity to make sound financial decisions across the lifespan is critical for interpersonal, occupational, and psychological health and success. In the present study, we explored how healthy younger and older adults make a series of increasingly complex financial decisions. One-hundred sixteen healthy older adults, aged 56–90 years, and 102 college undergraduates, completed the Financial Decision-Making Questionnaire, which requires selecting and justifying financial choices across four hypothetical scenarios and answering questions pertaining to financial knowledge. Results indicated that Older participants significantly outperformed Younger participants on a multiple-choice test of acquired financial knowledge. However, after controlling for such pre-existing knowledge, several age effects were observed. For example, Older participants were more likely to make immediate investment decisions, whereas Younger participants exhibited a preference for delaying decision-making pending additional information. Older participants also rated themselves as more concerned with avoiding monetary loss (i.e., a prevention orientation), whereas Younger participants reported greater interest in financial gain (i.e., a promotion orientation). In terms of sex differences, Older Males were more likely to pay credit card bills and utilize savings accounts than were Older Females. Multiple positive correlations were observed between Older participants’ financial decision-making ability and performance on neuropsychological measures of non-verbal intellect and executive functioning. Lastly, the ability to justify one’s financial decisions declined with age, among the Older participants. Several of the aforementioned results parallel findings from the medical decision-making literature, suggesting that older adults make decisions in a manner that conserves diminishing cognitive resources. PMID:22715322

  1. Effects of Age of English Exposure, Current Input/Output, and grade on bilingual language performance.

    PubMed

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

    2016-05-01

    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 about English and Spanish language use. Short tests of semantic and morphosyntactic development in Spanish and English were used to quantify children's knowledge of each language. There were significant interactions between AoEE and Current Input/Output for children at third grade in English and in both grades for Spanish. In English, the relationship between AoEE and language scores were linear for first- and third-graders. In Spanish a nonlinear relationship was observed. We discuss how much of the variance was accounted for by AoEE and Current Input/Output.

  2. 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.

  3. Elicited Imitation Performance at 20 Months Predicts Memory Abilities in School-Age Children

    PubMed Central

    Riggins, Tracy; Cheatham, Carol L.; Stark, Emily; Bauer, Patricia J.

    2012-01-01

    Over the first decade of life there are marked improvements in mnemonic abilities. An important question from both a theoretical and applied perspective is the extent of continuity in the nature of memory over this period. The present longitudinal investigation examined declarative memory during the transition from toddlerhood to school-age using both experimental and standardized assessments. Results indicate significant associations between immediate nonverbal recall at 20 months (measured by elicited imitation) and immediate verbal and nonverbal memory (measured by standardized and laboratory-based tasks) at 6 years in typically developing children. Regression models revealed this association was specific, as measures of language abilities and temperament were not predictive of later memory performance. These findings suggest both continuity and specificity within the declarative memory system over the first years of life. Theoretical and applied implications of these findings are discussed. PMID:24436638

  4. 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.

  5. 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

  6. 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

  7. Impact of patient's age and disease duration on cardiac performance in acromegaly: a radionuclide angiography study.

    PubMed

    Colao, A; Cuocolo, A; Marzullo, P; Nicolai, E; Ferone, D; Della Morte, A M; Petretta, M; Salvatore, M; Lombardi, G

    1999-05-01

    The aim of this study was to evaluate the impact of age and disease duration on cardiac performance in acromegaly. To address these issues, the left ventricular function at rest and during physical exercise was assessed by equilibrium radionuclide angiography in 40 rigorously selected patients with active acromegaly but without evidence of other complications able to affect heart function and in 32 healthy controls. Patients and controls were divided in two groups, on the basis of age below and above 40 yr. Circulating GH and insulin-like growth factor-I levels were significantly increased in patients, compared with controls, but were similar in the two groups of patients. At peak exercise, the systolic blood pressure was significantly higher in elderly patients (P < 0.001), whereas diastolic blood pressure was significantly higher in young patients than in age-matched controls (P < 0.01). Heart rate at peak exercise was significantly higher in young than in elderly patients and controls (P < 0.01), without any evidence of arrhythmia in both groups. The left ventricular ejection fraction at rest was normal (>50%) in all but 2 patients and in all controls. The left ventricular ejection fraction at peak exercise was significantly decreased in elderly, compared with young, patients (P < 0.01) and in age-matched controls (P < 0.001). A normal response of the left ventricular ejection fraction to exercise was found in 12 of 40 patients (30%) and in 28 of 32 controls (87.5%) (chi2, 5.764; P < 0.01). Exercise-induced changes in left ventricular ejection fraction were significantly decreased in young (+5.2 +/- 4.4% vs. +21.3 +/- 3.4%, P < 0.005) and elderly patients (-10.2 +/- 2.8% vs. +13.7 +/- 2.7%, P < 0.0001), as compared with age-matched controls. The peak rate of left ventricular filling was significantly higher in young, than in elderly, patients whether peak filling rate was normalized to end-diastolic volume (P < 0.001), or stroke volume (P < 0.0001), or expressed

  8. Menopausal Status and Physical Performance in Middle Aged Women: A Cross-Sectional Community-Based Study in Northeast Brazil

    PubMed Central

    da Câmara, Saionara M. A.; Zunzunegui, Maria Victoria; Pirkle, Catherine; Moreira, Mayle A.; Maciel, Álvaro C. C.

    2015-01-01

    Objective To examine associations between menopausal status and physical performance in middle-aged women from the Northeast region of Brazil. Methods Cross-sectional study of women between 40 to 65 years old living in Parnamirim. Women were recruited by advertisements in primary care neighborhood centers across the city. Physical performance was assessed by grip strength, gait speed and chair stands. Menopausal status was determined using the Stages of Reproductive Aging Workshop classification and women were classified in: premenopausal, perimenopausal or postmenopausal. Multiple linear regression analyses were performed to model the effect of menopausal status on each physical performance measure, adjusting for covariates (age, family income, education, body mass index, parity and age at first birth). Results The premenopausal women were significantly stronger and performed better in chair stands than perimenopausal and postmenopausal women. Gait speed did not vary significantly by menopausal status. In multivariate analyses, menopausal status remained statistically significant only for grip strength. In fully adjusted analyses, premenopausal women had grip strength mean of 2.226 Kgf (95% CI: 0.361 – 4.091) higher than the postmenopausal group. Conclusions This study provides further evidence for the associations between menopause and physical performance in middle-aged women, since grip strength is weaker in peri and postmenopausal women compared to premenopausal, even adjusted for age and other covariates. PMID:25822526

  9. Age-related differences in acceleration, maximum running speed, and repeated-sprint performance in young soccer players.

    PubMed

    Mendez-Villanueva, Alberto; Buchheit, Martin; Kuitunen, Sami; Douglas, Andrew; Peltola, Esa; Bourdon, Pitre

    2011-03-01

    We investigated age-related differences in the relationships among acceleration, maximum running speed, and repeated-sprint performance in 61 highly trained young male soccer players (Under 14, n = 14; Under 16, n = 22; Under 18, n = 25). We also examined the possible influence of anthropometry (stature, body mass, fat-free mass) and biological maturation (age at peak height velocity) on performance in those three sprint-running qualities. Players were tested for 10-m sprint (acceleration), flying 20-m sprint (maximum running speed), and 10 × 30-m sprint (repeated-sprint performance) times. Correlations between acceleration, maximum running speed, and repeated-sprint performance were positive and large to almost perfect (r = 0.55-0.96), irrespective of age group. There were age-based differences both in absolute performance in the three sprint-running qualities (Under 18 > Under 16 > Under 14; P < 0.001) and when body mass and fat-free mass were statistically controlled (P < 0.05). In contrast, all between-group differences disappeared after adjustment for age at peak height velocity (P > 0.05). The large correlations among acceleration, maximum running speed, and repeated-sprint performance in all age groups, as well as the disappearance of between-group differences when adjusted for estimated biological maturity, suggest that these physical qualities in young highly trained soccer players might be considered as a general quality, which is likely to be related to qualitative adaptations that accompany maturation.

  10. 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

  11. Age, training, and previous experience predict race performance in long-distance inline skaters, not anthropometry.

    PubMed

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

    2012-02-01

    The association of characteristics of anthropometry, training, and previous experience with race time in 84 recreational, long-distance, inline skaters at the longest inline marathon in Europe (111 km), the Inline One-eleven in Switzerland, was investigated to identify predictor variables for performance. Age, duration per training unit, and personal best time were the only three variables related to race time in a multiple regression, while none of the 16 anthropometric variables were related. Anthropometric characteristics seem to be of no importance for a fast race time in a long-distance inline skating race in contrast to training volume and previous experience, when controlled with covariates. Improving performance in a long-distance inline skating race might be related to a high training volume and previous race experience. Also, doing such a race requires a parallel psychological effort, mental stamina, focus, and persistence. This may be reflected in the preparation and training for the event. Future studies should investigate what motivates these athletes to train and compete.

  12. Does the Animal Fun program improve motor performance in children aged 4-6 years?

    PubMed

    Piek, J P; McLaren, S; Kane, R; Jensen, L; Dender, A; Roberts, C; Rooney, R; Packer, T; Straker, L

    2013-10-01

    The Animal Fun program was designed to enhance the motor ability of young children by imitating the movements of animals in a fun, inclusive setting. The efficacy of this program was investigated through a randomized controlled trial using a multivariate nested cohort design. Pre-intervention scores were recorded for 511 children aged 4.83 years to 6.17 years (M=5.42 years, SD=3.58 months). Six control and six intervention schools were compared 6 months later following the intervention, and then again at 18 months after the initial testing when the children were in their first school year. Changes in motor performance were examined using the Bruininks-Oseretsky Test of Motor Proficiency short form. Data were analyzed using multi-level-mixed effects linear regression. A significant Condition×Time interaction was found, F(2,1219)=3.35, p=.035, demonstrating that only the intervention group showed an improvement in motor ability. A significant Sex×Time interaction was also found, F(2,1219)=3.84, p=.022, with boys improving over time, but not girls. These findings have important implications for the efficacy of early intervention of motor skills and understanding the differences in motor performance between boys and girls. PMID:23186610

  13. Micronutrient interventions on cognitive performance of children aged 5-15 years in developing countries.

    PubMed

    Khor, Geok Lin; Misra, Snigdha

    2012-01-01

    It is estimated that more than 200 million young children worldwide fail to reach their potential in cognitive development owing to undernutrition. Numerous studies have assessed the effects of micronutrient supplementation on growth and cognitive development in infants, toddlers and preschoolers. However, micronutrient interventions on the cognitive performance of older children are limited. This article seeks to provide an update on micronutrient interventions and cognitive outcomes among children aged 5-15 years in developing countries. A total of 13 randomized controlled trials published since 2000 were identified. Majority of these studies assessed the effects of micronutrient-fortified foods on various domains of cognitive function. Among key micronutrients assessed were iron, zinc, iodine and vitamin A. This review found a lack of consistency in the impact of micronutrient supplementation on intelligence, long term mental functions and school examination grades of the children. A beneficial effect of micronutrient supplementation on short term memory was more consistently reported. Overall, the evidence from this review for the impact of micronutrients on cognitive performance in older children remains equivocal. In light of the growing interest on the influence of nutrition on cognition, it is important that culturally-appropriate and sufficiently sensitive assessment tools be used for measuring the desired cognitive outcomes that are most likely to be affected by the nutrients under study. PMID:23017305

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

    PubMed

    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

  15. Effect of age on 16.1-km time-trial performance.

    PubMed

    Balmer, James; Bird, Steve; Davison, Richard; Lucia, Alejandro

    2008-01-15

    In this study, we assessed the performance of trained senior (n = 6) and veteran (n = 6) cyclists (mean age 28 years, s = 3 and 57 years, s = 4 respectively). Each competitor completed two cycling tests, a ramped peak aerobic test and an indoor 16.1-km time-trial. The tests were performed using a Kingcycle ergometer with the cyclists riding their own bicycle fitted with an SRM powermeter. Power output, heart rate, and gas exchange variables were recorded continuously and blood lactate concentration [HLa] was assessed 3 min after the peak ramped test and at 2.5-min intervals during the time-trial. Peak values for power output (RMP(max)), heart rate (HR(peak)), oxygen uptake (VO2(peak)), and ventilation (V(Epeak)) attained during the ramped test were higher in the senior group (P < 0.05), whereas [HLa](peak), RER(peak), V(E): VO2(peak), and economy(peak) were similar between groups (P > 0.05). Time-trial values (mean for duration of race) for power output (W(TT)), heart rate (HR(TT)), VO2 (VO(2TT)), and V(E) (V(ETT)) were higher in the seniors (P < 0.05), but [HLa](TT), RER(TT), V(ETT): VO2(TT), and economy(TT) were similar between the groups (P > 0.05). Time-trial exercise intensity, expressed as %RMP(max), %HR(peak), % VO2(peak), and % V(Epeak), was similar (P > 0.05) for seniors and veterans (W(TT): 81%, s = 2 vs. 78%, s = 8; HR(TT): 96%, s = 4 vs. 94%, s = 4; VO2(TT): 92%, s = 4 vs. 95%, s = 10; V(ETT): 89%, s = 8 vs. 85%, s = 8, respectively). Overall, seniors attained higher absolute values for power output, heart rate, VO2, and V(E) but not blood lactate concentration, respiratory exchange ratio (RER), V(E): VO2, and economy. Veterans did not accommodate age-related declines in time trial performance by maintaining higher relative exercise intensity.

  16. Effects of age and recovery duration on performance during multiple treadmill sprints.

    PubMed

    Ratel, S; Williams, C A; Oliver, J; Armstrong, N

    2006-01-01

    The aim of this study was to investigate the effects of age and recovery duration on performance during multiple treadmill sprints. Twelve boys (11.7 +/- 0.5 y) and thirteen men (22.1 +/- 2.9 y) performed ten consecutive 10-s sprints on a non-motorised treadmill separated by 15-s (R15) and 180-s (R180) passive recovery intervals. Mean power output (MPO), mean force output (MFO), running velocity, step length, and step rate were calculated for each sprint. Capillary blood samples were drawn from the fingertip at rest and 3 min after the tenth sprint to measure the lactate accumulation (Delta [La]). With R15, all mechanical parameters decreased significantly less in the boys than in the men over the ten sprints (MPO: - 28.9 vs. - 47.0 %, MFO: - 13.1 vs. - 25.6 %, running velocity: - 18.8 vs. - 29.4 %, p < 0.001, respectively). With R180, all mechanical values remained unchanged in the boys. In the men, MPO and MFO significantly decreased over the ten sprints (- 7.8 % and - 4.6 %, p < 0.05, respectively). The running velocity, however, did not decrease because the decrease in step rate (p < 0.001) was compensated by an increase in step length. For either recovery interval, Delta [La] values were higher in the men compared to the boys (R15: 12.7 vs. 7.7 mmol . L (-1), p < 0.001, R180: 10.7 vs. 7.7 mmol . L (-1), p < 0.05). To conclude, the boys maintained more easily their running performance than the men during repeated treadmill sprints with R15. Three-minute recovery periods were sufficient in the boys to repeat short running sprints without substantial fatigue. Despite the decrease in power and force outputs with R180, the young men were able to maintain their running velocity during the test. PMID:16388435

  17. A comparison of participation and performance in age-group finishers competing in and qualifying for Ironman Hawaii

    PubMed Central

    Stiefel, Michael; Rüst, Christoph Alexander; Rosemann, Thomas; Knechtle, Beat

    2013-01-01

    Background Athletes intending to compete in Ironman Hawaii need to qualify in an age-group based qualification system. We compared participation and top ten performances of athletes in various age groups between Ironman Hawaii and its qualifier races. Methods Finishes in Ironman Hawaii and in its qualifier races in 2010 were analyzed in terms of performance, age, and sex. Athletes were categorized into age groups from 18–24 to 75–79 years and split and race times were determined for the top ten athletes in each age group. Results A higher proportion of athletes aged 25–49 years finished in the qualifier races than in Ironman Hawaii. In athletes aged 18–24 and 50–79 years, the percentage of finishes was higher in Ironman Hawaii than in the qualifier races. For women, the fastest race times were slower in Ironman Hawaii than in the qualifier races for those aged 18–24 (P<0.001), 25–29 (P<0.05), and 60–64 (P<0.05) years. Swim split times were slower in Ironman Hawaii than in the qualifier races for all age groups (P<0.05). Cycling times were slower in Ironman Hawaii for 18–24, 25–29, 40–44, 50–54, and 60–64 years (P<0.05) in age groups. For men, finishers aged 18–24 (P<0.001), 40–44 (P<0.001), 50–54 (P<0.01), 55–59 (P<0.001), 60–64 (P<0.01), and 65–69 (P<0.001) years were slower in Ironman Hawaii than in the qualifier races. Swim split times were slower in Ironman Hawaii than in the qualifier races for all age groups (P<0.05). Cycling times were slower in Ironman Hawaii for those aged 18–24 and those aged 40 years and older (P<0.05). Conclusion There are differences in terms of participation and performance for athletes in different age groups between Ironman Hawaii and its qualifier races. Triathletes aged 25–49 years and men generally were underrepresented in Ironman Hawaii compared with in its Ironman qualifier races. These athletes may have had less chance to qualify for Ironman Hawaii than female athletes or younger (<25

  18. "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…

  19. 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

  20. 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.

  1. Extended Aging of Ag/W Circuit Breaker Contacts: Influence on Surface Structure, Electrical Properties, and UL Testing Performance

    NASA Astrophysics Data System (ADS)

    Yu, Haibo; Kesim, M. Tumerkan; Sun, Yu; Harmon, Jason; Potter, Jonathan; Alpay, S. Pamir; Aindow, Mark

    2016-01-01

    Samples of 120 V, 30 A commercial circuit breakers were subjected to various aging treatments and the resulting microstructures at the surfaces of the Ag/W contacts were studied using a combination of x-ray diffraction, scanning electron microscopy, and energy-dispersive x-ray spectroscopy techniques. Breakers aged naturally in a hot, humid climate were compared to those subjected to accelerated aging in dry and humid environments. The most extensive oxidation was observed for contacts from breakers subjected to accelerated humid aging; these contacts exhibited thick surface layers consisting of Ag2O, Ag2WO4, Cu(OH)2•H2O, and WO3 phases. Far less surface degradation was observed for dry-aged contacts. Naturally aged contacts showed variations in degradation with more oxidation at the surface regions outside the physical contact area on the contact face. A correlation was found between the contact resistances measured from these samples following ASTM standard B 667-97 and the observed surface microstructures. To evaluate the effects of the surface oxides on breaker performance, humid-aged breakers were subjected to standardized UL overload/temperature-rise, endurance, and short-circuit testing following UL489. The contacts in these breakers exhibit similar microstructural and property changes to those observed previously for as-manufactured contacts after UL testing. These data illustrate the robust performance of this contact technology even after being subjected to aggressive artificial aging.

  2. It matters how old you feel: Antecedents and performance consequences of average relative subjective age in organizations.

    PubMed

    Kunze, Florian; Raes, Anneloes M L; Bruch, Heike

    2015-09-01

    This article extends the conceptual knowledge of average relative subjective age in organizations by exploring organizational-level antecedents and consequences of employees, on average, feeling younger than their chronological age. We draw from the theories of selection-optimization-compensation and socioemotional selectivity to build a theoretical framework for relative subjective age in organizations. We hypothesize that companies in which employees, on average, perceive themselves to be younger than they actually are have a higher average individual goal accomplishment and, in turn, experience higher company performance. We further hypothesize that employees' average experience of high work-related meaning relates to a lower subjective age in organizations. In addition, we assess the role of environmental dynamism and age-inclusive human resource management as moderators in this theoretical model. Through empirically testing this model in a multisource dataset, including 107 companies with 15,164 participating employees, we received support for the hypothesized relationships. Our results contribute to current debates in the scientific literature on age and have important practical implications in light of the demographic changes faced by many companies. This research indicates to both researchers and practitioners that it is not employees' chronological age but their subjective age, a factor that can be influenced, which drives organizational performance outcomes.

  3. It matters how old you feel: Antecedents and performance consequences of average relative subjective age in organizations.

    PubMed

    Kunze, Florian; Raes, Anneloes M L; Bruch, Heike

    2015-09-01

    This article extends the conceptual knowledge of average relative subjective age in organizations by exploring organizational-level antecedents and consequences of employees, on average, feeling younger than their chronological age. We draw from the theories of selection-optimization-compensation and socioemotional selectivity to build a theoretical framework for relative subjective age in organizations. We hypothesize that companies in which employees, on average, perceive themselves to be younger than they actually are have a higher average individual goal accomplishment and, in turn, experience higher company performance. We further hypothesize that employees' average experience of high work-related meaning relates to a lower subjective age in organizations. In addition, we assess the role of environmental dynamism and age-inclusive human resource management as moderators in this theoretical model. Through empirically testing this model in a multisource dataset, including 107 companies with 15,164 participating employees, we received support for the hypothesized relationships. Our results contribute to current debates in the scientific literature on age and have important practical implications in light of the demographic changes faced by many companies. This research indicates to both researchers and practitioners that it is not employees' chronological age but their subjective age, a factor that can be influenced, which drives organizational performance outcomes. PMID:25798554

  4. A twin study of spatial and non-spatial delayed response performance in middle age.

    PubMed

    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

    2011-06-01

    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 influences). Non-spatial alternation (NSA), which may involve greater reliance on processing of subgoals, was significantly more difficult than spatial alternation (SA). Despite their similarities, NSA and SA scores were uncorrelated. NSA performance was worse when administered second; there was no SA order effect. NSA scores were modestly heritable (h(2)=.25; 26); SA was not. There was shared genetic variance between NSA scores and general intellectual ability (r(g)=.55; .67), but this also suggests genetic influences specific to NSA. Compared with findings from small, selected control samples, high "failure" rates in this community-based sample raise concerns about interpretation of brain dysfunction in elderly or patient samples.

  5. National differences in environmental concern and performance are predicted by country age.

    PubMed

    Hershfield, Hal E; Bang, H Min; Weber, Elke U

    2014-01-01

    There are obvious economic predictors of ability and willingness to invest in environmental sustainability. Yet, given that environmental decisions represent trade-offs between present sacrifices and uncertain future benefits, psychological factors may also play a role in country-level environmental behavior. Gott's principle suggests that citizens may use perceptions of their country's age to predict its future continuation, with longer pasts predicting longer futures. Using country- and individual-level analyses, we examined whether longer perceived pasts result in longer perceived futures, which in turn motivate concern for continued environmental quality. Study 1 found that older countries scored higher on an environmental performance index, even when the analysis controlled for country-level differences in gross domestic product and governance. Study 2 showed that when the United States was framed as an old country (vs. a young one), participants were willing to donate more money to an environmental organization. The findings suggest that framing a country as a long-standing entity may effectively prompt proenvironmental behavior. PMID:24264938

  6. 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.

  7. 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. PMID:26943739

  8. National differences in environmental concern and performance are predicted by country age.

    PubMed

    Hershfield, Hal E; Bang, H Min; Weber, Elke U

    2014-01-01

    There are obvious economic predictors of ability and willingness to invest in environmental sustainability. Yet, given that environmental decisions represent trade-offs between present sacrifices and uncertain future benefits, psychological factors may also play a role in country-level environmental behavior. Gott's principle suggests that citizens may use perceptions of their country's age to predict its future continuation, with longer pasts predicting longer futures. Using country- and individual-level analyses, we examined whether longer perceived pasts result in longer perceived futures, which in turn motivate concern for continued environmental quality. Study 1 found that older countries scored higher on an environmental performance index, even when the analysis controlled for country-level differences in gross domestic product and governance. Study 2 showed that when the United States was framed as an old country (vs. a young one), participants were willing to donate more money to an environmental organization. The findings suggest that framing a country as a long-standing entity may effectively prompt proenvironmental behavior.

  9. Protective effect of practice on cognition during aging: implications for predictive characteristics of performance and efficacy of practice.

    PubMed

    Markowska, Alicja L; Savonenko, Alena V

    2002-09-01

    In the present study, the effect of previous experience on spatial memory, which required the retention of information either over long intervals or within a single session, was longitudinally tested in the water maze in male F-344 rats that were from 6 to 24 months of age. Performance in these tasks was found to be age-dependent (Markowska, 1999). Other behavioral tasks in the straight alley and with a visible platform in the water maze controlled the noncognitive components of performance. For all tasks, performance was significantly correlated between 12-month-old and 18-month-old rats, indicating that cognitive performance at the early, but not advanced, stage of aging could be predicted from performance at a younger age if the novelty of the first exposure to the task was eliminated. The protective effect of experience was more robust in the reference memory task as compared to the working memory task and was modified by age when training was initiated. Behavior during the probe trials was more sensitive to the effect of aging and more resistant to the beneficial effect of practice as compared to the performance in the platform trials. The speed of swimming of experienced rats progressively decreased with age only when tested in the cognitive tasks but not in the straight alley. This indicates that speed of swimming during cognitive tasks does not exclusively reflect the ability to swim, but might be also affected by the cognitive demands of the task. Protective effect of experience on cognition was not modified by restriction in diet.

  10. Performances on a cognitive theory of mind task: specific decline or general cognitive deficits? Evidence from normal aging.

    PubMed

    Fliss, Rafika; Lemerre, Marion; Mollard, Audrey

    2016-06-01

    Compromised theory of mind (ToM) can be explained either by a failure to implement specific representational capacities (mental state representations) or by more general executive selection demands. In older adult populations, evidence supporting affected executive functioning and cognitive ToM in normal aging are reported. However, links between these two functions remain unclear. In the present paper, we address these shortcomings by using a specific task of ToM and classical executive tasks. We studied, using an original cognitive ToM task, the effect of age on ToM performances, in link with the progressive executive decline. 96 elderly participants were recruited. They were asked to perform a cognitive ToM task, and 5 executive tests (Stroop test and Hayling Sentence Completion Test to appreciate inhibitory process, Trail Making Test and Verbal Fluency for shifting assessment and backward span dedicated to estimate working memory capacity). The results show changes in cognitive ToM performance according to executive demands. Correlational studies indicate a significant relationship between ToM performance and the selected executive measures. Regression analyzes demonstrates that level of vocabulary and age as the best predictors of ToM performance. The results are consistent with the hypothesis that ToM deficits are related to age-related domain-general decline rather than as to a breakdown in specialized representational system. The implications of these findings for the nature of social cognition tests in normal aging are also discussed. PMID:27277154

  11. Performances on a cognitive theory of mind task: specific decline or general cognitive deficits? Evidence from normal aging.

    PubMed

    Fliss, Rafika; Lemerre, Marion; Mollard, Audrey

    2016-06-01

    Compromised theory of mind (ToM) can be explained either by a failure to implement specific representational capacities (mental state representations) or by more general executive selection demands. In older adult populations, evidence supporting affected executive functioning and cognitive ToM in normal aging are reported. However, links between these two functions remain unclear. In the present paper, we address these shortcomings by using a specific task of ToM and classical executive tasks. We studied, using an original cognitive ToM task, the effect of age on ToM performances, in link with the progressive executive decline. 96 elderly participants were recruited. They were asked to perform a cognitive ToM task, and 5 executive tests (Stroop test and Hayling Sentence Completion Test to appreciate inhibitory process, Trail Making Test and Verbal Fluency for shifting assessment and backward span dedicated to estimate working memory capacity). The results show changes in cognitive ToM performance according to executive demands. Correlational studies indicate a significant relationship between ToM performance and the selected executive measures. Regression analyzes demonstrates that level of vocabulary and age as the best predictors of ToM performance. The results are consistent with the hypothesis that ToM deficits are related to age-related domain-general decline rather than as to a breakdown in specialized representational system. The implications of these findings for the nature of social cognition tests in normal aging are also discussed.

  12. Within-Individual Variability in Neurocognitive Performance: Age and Sex-Related Differences in Children and Youths From Ages 8 to 21

    PubMed Central

    Roalf, David R.; Gur, Raquel E.; Ruparel, Kosha; Calkins, Monica E.; Satterthwaite, Theodore D.; Bilker, Warren B.; Hakonarson, Hakon; Harris, Lauren Julius; Gur, Ruben C.

    2014-01-01

    Objective The transition from childhood to adulthood is characterized by improved motor and cognitive performance in many domains. Developmental studies focus on average performance in single domains but ignore consistency of performance across domains. Within-individual variability (WIV) provides an index of that evenness and is a potential marker of development. Method We gave a computerized battery of 14 neurocognitive tests to 9138 youths ages 8-21 from the Philadelphia Neurodevelopmental Cohort. Results As expected, performance improved with age, both accuracy and speed peaking in adulthood. WIV, however, showed a U-shaped course: highest in childhood, declining yearly into mid-adolescence, and increasing again into adulthood. Young females outperformed and were less variable than males, but by early adulthood male performance matched that of females despite being more variable. Conclusion We conclude that WIV declines from childhood to adolescence as developmental lags are overcome, and then increases into adulthood reflecting the emergence of cognitive specializations related to skill-honing and brain maturation. PMID:24773417

  13. The three-panel runway maze adapted to Microcebus murinus reveals age-related differences in memory and perseverance performances.

    PubMed

    Trouche, Stéphanie G; Maurice, Tangui; Rouland, Sylvie; Verdier, Jean-Michel; Mestre-Francés, Nadine

    2010-07-01

    Microcebus murinus, a mouse lemur primate appears to be a valuable model for cerebral aging study and for Alzheimer's disease model since they can develop beta-amyloid plaques with age. Although the biological and biochemical analyses of cerebral aging are well documented, the cognitive abilities of this primate have not been thoroughly characterized. In this study, we adapted a spatial working memory procedure described in rodents, the sequential choice task in the three-panel runway, to mouse lemurs. We analyzed the age-related differences in a procedural memory task in the absence or presence of visual cues. Sixty percent of young adult and 48% of aged lemurs completed the exploratory, choice habituation and testing phases at the beginning of the procedure. Young adult lemurs showed a higher level of perseverative errors compared with aged animals, particularly in the presence of visual stimuli. Over trials, old animals made more reference errors compared to young ones that improved quickly their performances under random level. No significant improvement was observed in young adults and old ones over sessions. This study showed that behavioural performances of M. murinus assessed on the sequential choice task in the three-panel runway markedly differ from the previously reported abilities of rodents. The behavioural response of young adult lemurs was influenced by novelty-related anxiety that contributed to their performance in terms of perseverative errors. Conversely, aged lemurs showed less perseverative errors, a rapid habituation to the three-panel runway maze, but made more memory errors. Overall, these findings demonstrate the feasibility to use the three-panel runway task in assessing memory performance, particularly in aged mouse lemurs.

  14. 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.

  15. [Development of a method for estimation of physical fitness age for the evaluation of physical performance levels].

    PubMed

    Oda, S

    1992-10-01

    The aims of this study are to develop a method for estimation of physical fitness age for the evaluation of physical performance levels and to examine the efficacy and adaptability of the method. Physical fitness data collected on 15,845 subjects from 23 health promotion centers in Japan, during a 2-year period, 1985-1986, were analysed by correlation analysis to find factors which affect physical performance. From this analysis, stature and exercise habit were selected as factors to be considered in the computation of physical fitness age. For determination of physical fitness and its relation to chronological age, four tests, side step, sit-ups, vertical jump and wing lift were selected from results of correlation and multiple regression analysis and an estimation equation for physical fitness age was developed by stepwise multiple regression analysis, in which the subjective variable is physical fitness data and objective variables are chronological age and height, on 9,528 people without habitual physical activities. Physical fitness age for each fitness test was calculated from the equation and mean individual physical fitness age computed. The suitability of the developed method was tested on other groups with results showing that the developed method was generally applicable to the other group and was exact enough to evaluate the characteristics of the physical level of the group. Analysis of the relation between health indices and physical fitness age obtained by this new method, revealed that the group in which physical fitness age is inferior to chronological age contained relatively more hypertensive patients and obese people.

  16. 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

  17. 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.

  18. 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…

  19. 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…

  20. 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…

  1. 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…

  2. Determination of Age-Dependent Reference Ranges for Coagulation Tests Performed Using Destiny Plus

    PubMed Central

    Arslan, Fatma Demet; Serdar, Muhittin; Merve Ari, Elif; Onur Oztan, Mustafa; Hikmet Kozcu, Sureyya; Tarhan, Huseyin; Cakmak, Ozgur; Zeytinli, Merve; Yasar Ellidag, Hamit

    2016-01-01

    Background In order to apply the right treatment for hemostatic disorders in pediatric patients, laboratory data should be interpreted with age-appropriate reference ranges. Objectives The purpose of this study was to determining age-dependent reference range values for prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen tests, and D-dimer tests. Materials and Methods A total of 320 volunteers were included in the study with the following ages: 1 month - 1 year (n = 52), 2 - 5 years (n = 50), 6 - 10 years (n = 48), 11 - 17 years (n = 38), and 18 - 65 years (n = 132). Each volunteer completed a survey to exclude hemostatic system disorder. Using a nonparametric method, the lower and upper limits, including 95% distribution and 90% confidence intervals, were calculated. Results No statistically significant differences were found between PT and aPTT values in the groups consisting of children. Thus, the reference ranges were separated into child and adult age groups. PT and aPTT values were significantly higher in the children than in the adults. Fibrinogen values in the 6 - 10 age group and the adult age group were significantly higher than in the other groups. D-dimer levels were significantly lower in those aged 2 - 17; thus, a separate reference range was established. Conclusions These results support other findings related to developmental hemostasis, confirming that adult and pediatric age groups should be evaluated using different reference ranges. PMID:27617078

  3. Age Differences in Affective Decision Making as Indexed by Performance on the Iowa Gambling Task

    ERIC Educational Resources Information Center

    Cauffman, Elizabeth; Shulman, Elizabeth P.; Steinberg, Laurence; Claus, Eric; Banich, Marie T.; Graham, Sandra; Woolard, Jennifer

    2010-01-01

    Contemporary perspectives on age differences in risk taking, informed by advances in developmental neuroscience, have emphasized the need to examine the ways in which emotional and cognitive factors interact to influence decision making. In the present study, a diverse sample of 901 individuals between the ages of 10 and 30 were administered a…

  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. Survival Prediction Score: A Simple but Age-Dependent Method Predicting Prognosis in Patients Undergoing Palliative Radiotherapy

    PubMed Central

    Dalhaug, Astrid; Pawinski, Adam; Haukland, Ellinor

    2014-01-01

    Purpose. Validation of a Canadian three-tiered prognostic model (survival prediction score, SPS) in Norwegian cancer patients referred for palliative radiotherapy (PRT), and evaluation of age-dependent performance of the model. Patients and Methods. We analyzed all 579 PRT courses administered at a dedicated PRT facility between 20.06.07 and 31.12.2009. SPS was assigned as originally described, That is, by taking into consideration three variables: primary cancer type, site of metastases, and performance status. Results. Patients with poor prognosis (non-breast cancer, metastases other than bone, and Karnofsky performance status (KPS) ≤ 60) had median survival of 13 weeks. Those with intermediate prognosis (two of these parameters) survived for a median of 29 weeks, and patients with good prognosis for a median of 114 weeks, P < 0.001. While this model performed well in patients who were 60 years or older, it was less satisfactory in younger patients (no significant difference between the good and intermediate prognosis groups). Conclusion. SPS should mainly be used to predict survival of elderly cancer patients. However, even in this group accuracy is limited because the good prognosis group contained patients with short survival, while the poor prognosis group contained long-term survivors. Thus, improved models should be developed. PMID:25006508

  6. Age-dependent decline in learning and memory performances of WAG/Rij rat model of absence epilepsy

    PubMed Central

    2012-01-01

    Recent clinical studies revealed emotional and cognitive impairments associated with absence epilepsy. Preclinical research with genetic models of absence epilepsy however have primarily focused on dysfunctional emotional processes and paid relatively less attention to cognitive impairment. In order to bridge this gap, we investigated age-dependent changes in learning and memory performance, anxiety-like behavior, and locomotor activity of WAG/Rij rats (a valid model of generalized absence epilepsy) using passive avoidance, Morris water maze, elevated plus maze, and locomotor activity cage. We tested 5 month-old and 13 month-old WAG/Rij rats and compared their performance to age-matched Wistar rats. Results revealed a decline in emotional and spatial memory of WAG/Rij rats compared to age-matched Wistar rats only at 13 months of age. Importantly, there were no significant differences between WAG/Rij and Wistar rats in terms of anxiety-like behavior and locomotor activity at either age. Results pointed at age-dependent learning and memory deficits in the WAG/Rij rat model of absence epilepsy. PMID:22998946

  7. 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

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

    PubMed

    Bock, Otmar; 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

  9. [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. PMID:12806505

  10. Pre-training blocks the improving effect of tetrahydroaminoacridine and D-cycloserine on spatial navigation performance in aged rats.

    PubMed

    Aura, J; Riekkinen, P

    2000-03-01

    We investigated the effect of pre-training on the improvement of spatial navigation performance provided by a cholinesterase inhibitor, tetrahydroaminoacridine (3 mg/kg, i.p.), and a positive modulator of NMDA receptor, D-cycloserine (10 mg/kg, i.p.), or their combination in aged rats. Pre-training consisted of spatial or non-spatial conditions and took place in either the same or a separate room. We found that any kind of pre-training was able to eliminate the enhancing effect of tetrahydroaminoacridine and D-cycloserine on spatial navigation. However, none of these pre-training conditions was able to block the age-related deficit in spatial navigation. These results indicate that tetrahydroaminoacridine and D-cycloserine, separately or in combination, do not themselves alleviate the age-related spatial memory deficit, but may enhance procedural aspects of water maze learning in aged rats.

  11. Daily iron supplementation on cognitive performance in primary-school-aged children with and without anemia: a meta-analysis

    PubMed Central

    Guo, Xiu-min; Liu, Hui; Qian, Jing

    2015-01-01

    Anemia is an important public health and clinical problem. Observational studies have linked iron deficiency and anemia in children with many poor outcomes, including impaired cognitive development. In this study, we summarize the evidence for the effect of daily iron supplementation on cognitive performance in primary-school-aged children. We searched electronic databases (including MEDLINE and Wangfang database) and other sources (August 2015) for randomized and quasi-randomized controlled trials involving daily iron supplementation on cognitive performance in children aged 5-12 years. We combined the data using random effects meta-analysis. We identified 3219 studies; of these, we evaluated 5 full-text papers including 1825 children. Iron supplementation cannot improve global cognitive scores (Mean difference 1.05, 95% confidence interval [CI] -2.69 to 4.79, P<0.01). Our analysis suggests that iron supplementation improves global cognitive c outcomes among primary-school-aged children is still unclear. PMID:26629120

  12. Daily iron supplementation on cognitive performance in primary-school-aged children with and without anemia: a meta-analysis.

    PubMed

    Guo, Xiu-Min; Liu, Hui; Qian, Jing

    2015-01-01

    Anemia is an important public health and clinical problem. Observational studies have linked iron deficiency and anemia in children with many poor outcomes, including impaired cognitive development. In this study, we summarize the evidence for the effect of daily iron supplementation on cognitive performance in primary-school-aged children. We searched electronic databases (including MEDLINE and Wangfang database) and other sources (August 2015) for randomized and quasi-randomized controlled trials involving daily iron supplementation on cognitive performance in children aged 5-12 years. We combined the data using random effects meta-analysis. We identified 3219 studies; of these, we evaluated 5 full-text papers including 1825 children. Iron supplementation cannot improve global cognitive scores (Mean difference 1.05, 95% confidence interval [CI] -2.69 to 4.79, P<0.01). Our analysis suggests that iron supplementation improves global cognitive c outcomes among primary-school-aged children is still unclear.

  13. Driver distraction: the effects of concurrent in-vehicle tasks, road environment complexity and age on driving performance.

    PubMed

    Horberry, Tim; Anderson, Janet; Regan, Michael A; Triggs, Thomas J; Brown, John

    2006-01-01

    This paper presents the findings of a simulator study that examined the effects of distraction upon driving performance for drivers in three age groups. There were two in-vehicle distracter tasks: operating the vehicle entertainment system and conducting a simulated hands-free mobile phone conversation. The effect of visual clutter was examined by requiring participants to drive in simple and complex road environments. Overall measures of driving performance were collected, together with responses to roadway hazards and subjective measures of driver perceived workload. The two in-vehicle distraction tasks degraded overall driving performance, degraded responses to hazards and increased subjective workload. The performance decrements that occurred as a result of in-vehicle distraction were observed in both the simple and complex highway environments and for drivers in different age groups. One key difference was that older drivers traveled at lower mean speeds in the complex highway environment compared with younger drivers. The conclusions of the research are that both in-vehicle tasks impaired several aspects of driving performance, with the entertainment system distracter having the greatest negative impact on performance, and that these findings were relatively stable across different driver age groups and different environmental complexities. PMID:16226211

  14. 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

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

    PubMed

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

    2015-12-22

    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

  16. 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…

  17. 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…

  18. 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…

  19. 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…

  20. 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

  1. 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.

  2. 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. PMID:22076093

  3. 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

  4. 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.

  5. 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. PMID:26785760

  6. 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

  7. 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. PMID:26280383

  8. 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.

  9. 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

  10. 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…

  11. 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…

  12. The Influence of Education and Age on Neurocognitive Test Performance in Alzheimer's Disease and Vascular Dementia

    ERIC Educational Resources Information Center

    DenBesten, Nicholas P.

    2009-01-01

    This research involves an examination of the relationship between education and age on a wide array of neuropsychological test measures among patients diagnosed with Alzheimer's and vascular dementia. The purpose of this study was to investigate the role of education as an attenuating factor to neurocognitive decline in dementia. Although numerous…

  13. 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…

  14. 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,…

  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. Reduced specificity of functional connectivity in the aging brain during task performance.

    PubMed

    Geerligs, Linda; Maurits, Natasha M; Renken, Remco J; Lorist, Monicque M

    2014-01-01

    The importance of studying connectivity in the aging brain is increasingly recognized. Recent studies have shown that connectivity within the default mode network is reduced with age and have demonstrated a clear relation of these changes with cognitive functioning. However, research on age-related changes in other functional networks is sparse and mainly focused on prespecified functional networks. Using functional magnetic resonance imaging, we investigated age-related changes in functional connectivity during a visual oddball task in a range of functional networks. It was found that compared with young participants, elderly showed a decrease in connectivity between areas belonging to the same functional network. This was found in the default mode network and the somatomotor network. Moreover, in all identified networks, elderly showed increased connectivity between areas within these networks and areas belonging to different functional networks. Decreased connectivity within functional networks was related to poorer cognitive functioning in elderly. The results were interpreted as a decrease in the specificity of functional networks in older participants.

  17. Effects of aging and tactile stochastic resonance on postural performance and postural control in a sensory conflict task.

    PubMed

    Dettmer, Marius; Pourmoghaddam, Amir; Lee, Beom-Chan; Layne, Charles S

    2015-01-01

    Postural control in certain situations depends on functioning of tactile or proprioceptive receptors and their respective dynamic integration. Loss of sensory functioning can lead to increased risk of falls in challenging postural tasks, especially in older adults. Stochastic resonance, a concept describing better function of systems with addition of optimal levels of noise, has shown to be beneficial for balance performance in certain populations and simple postural tasks. In this study, we tested the effects of aging and a tactile stochastic resonance stimulus (TSRS) on balance of adults in a sensory conflict task. Nineteen older (71-84 years of age) and younger participants (22-29 years of age) stood on a force plate for repeated trials of 20 s duration, while foot sole stimulation was either turned on or off, and the visual surrounding was sway-referenced. Balance performance was evaluated by computing an Equilibrium Score (ES) and anterior-posterior sway path length (APPlength). For postural control evaluation, strategy scores and approximate entropy (ApEn) were computed. Repeated-measures ANOVA, Wilcoxon signed-rank tests, and Mann-Whitney U-tests were conducted for statistical analysis. Our results showed that balance performance differed between older and younger adults as indicated by ES (p = 0.01) and APPlength (0.01), and addition of vibration only improved performance in the older group significantly (p = 0.012). Strategy scores differed between both age groups, whereas vibration only affected the older group (p = 0.025). Our results indicate that aging affects specific postural outcomes and that TSRS is beneficial for older adults in a visual sensory conflict task, but more research is needed to investigate the effectiveness in individuals with more severe balance problems, for example, due to neuropathy. PMID:25884289

  18. Interactions between cold ambient temperature and older age on haptic acuity and manual performance.

    PubMed

    Tajmir, Panteha; Grierson, Lawrence E M; Carnahan, Heather

    2013-06-01

    The impact of exposure to cold on individuals' motor skills demands a deeper understanding of the ways in which cold weather influences psychomotor and haptic performance. In this study, various facets of psychomotor performance were evaluated in order to determine the impacts of ambient cold exposure on older persons. Healthy younger and older persons performed a battery of haptic psychomotor tests at room (23° C) and cold (1° C) ambient temperatures. The results indicate that older individuals do not perform as well as younger persons across the battery of tests, with cold temperature further degrading their performance in dexterity tasks (in, for example, Minnesota Manual Dexterity test placing: F [1, 16] = 10.23, p < .01) and peak precision grip force generation (F [1, 16] = 18.97, p < .01). The results suggest that cold weather may have an impact on the occupations older persons are able to perform during the winter months.

  19. 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.

  20. Does the conservation of resources motivate middle-aged women to perform physical activity?

    PubMed

    Rotem, Mina; Epstein, Leon; Ehrenfeld, Mally

    2009-12-01

    This article aims to examine the factors that motivate middle-aged women to engage in leisure physical activity (LPA) and to explore the relationship between resources loss and gains and engaging in LPA. It is a cross-sectional study based on a self-reported questionnaire (n = 949), using variables of the conservation of resources theory and the theory of planned behavior. Results show that women who engage in physical activity experience lower resources loss than inactive women. The longer they engage in physical activity, the less they experience losses such as youth, attractiveness, optimism, health, and beauty. Conservation of resources, perceived behavioral control, attitudes, and normative beliefs predict 41% (p < .0001) of the variance in the engagement in leisure physical activity. Findings suggest that constructing effective strategies to promote LPA requires also addressing these factors, which are valued by middle-aged women.

  1. Reading performance with various lamps in age-related macular degeneration.

    PubMed

    Eperjesi, F; Maiz-Fernandez, C; Bartlett, H E

    2007-01-01

    The purpose of this study was to determine if there was an objective difference in reading between four commonly available lamps, of varying spectral radiance, for 13 subjects with age-related maculopathy (ARM) or non-exudative age-related macular degeneration (AMD)--logMAR visual acuity between 0.04 and 0.68. At a constant illuminance of 2000 lux, there was no interaction between ARM and AMD subgroups and no statistically significant difference between the lamps: standard (clear envelope) incandescent, daylight simulation (blue tint envelope) incandescent, compact fluorescent and halogen incandescent, for any reading outcome measure (threshold print size p = 0.67, critical print size p = 0.74, acuity reserve p = 0.84 and mean reading rate p = 0.78). For lamps typically used in low-vision rehabilitation, a clinically significant effect of spectral radiance on reading for people with ARM or non-exudative AMD is unlikely.

  2. Depth-Charge in the Archive: The Documentation of Performance Revisited in the Digital Age

    ERIC Educational Resources Information Center

    Allen, Jess

    2010-01-01

    The debate surrounding the documentation of performance is principally concerned with the ephemerality of the live event, set against the stasis and "death" that the archive is conventionally believed to represent. The advent of digital technology in live performance has complexified this still further, by altering the architecture, space and…

  3. 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…

  4. The Effects of Age and Number of Demonstrations on Modeling of Form and Performance.

    ERIC Educational Resources Information Center

    Feltz, Deborah L.

    1982-01-01

    In a research study, fourth-grade, fifth-grade, and college females performed the Bachman Free-Standing Ladder-Balance task after watching four, eight, and twelve, or no videotaped demonstrations of the task. The videotape modeling seemed to affect form (or strategy) of their performances more than their final scores. (PP)

  5. How Japanese adults perceive memory change with age: middle-aged adults with memory performance as high as young adults evaluate their memory abilities as low as older adults.

    PubMed

    Kinjo, Hikari; Shimizu, Hiroyuki

    2014-01-01

    The characteristics of self-referent beliefs about memory change with age. The relationship between beliefs and memory performance of three age groups of Japanese adults was investigated. The beliefs measured by the Personal Beliefs about Memory Instrument (Lineweaver & Hertzog, 1998) differed among the age groups and between sexes. In most scales, the ratings by middle-aged adults were as low as those by older adults, which were lower than those by young adults. Women perceived their memory abilities as lower than men's, with no interaction between age and sex, suggesting the difference remains across the lifespan. For middle-aged adults, the better they performed in cued-recall, free recall, and recognition, the lower they evaluated their memory self-efficacy, while few relationships were found for other groups. Our results suggest that cognitive beliefs change with age and that investigating the beliefs of the middle-aged adults is indispensable to elucidate the transition of beliefs. PMID:24669510

  6. 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.

  7. 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. PMID:12096738

  8. Effects of Emotion and Age on Performance During a Think/No-Think Memory Task

    PubMed Central

    Murray, Brendan D.; Muscatell, Keely A.; Kensinger, Elizabeth A.

    2011-01-01

    Recent studies have demonstrated that young adults can voluntarily suppress information from memory when directed to. After learning novel word pairings to criterion, participants are shown individual words and instructed either to “think” about the associated word, or to put it out of mind entirely (“no-think”). When given a surprise cued recall test, participants typically show impaired recall for “no-think” words relative to “think” or “control” (un-manipulated) words. The present study investigated whether this controlled suppression effect persists in an aged population, and examined how the emotionality of the to-be-suppressed word affects suppression ability. Data from four experiments using the think/no-think task demonstrate that older and younger adults can suppress information when directed to (Experiment 1), and the age groups do not differ significantly in this ability. Experiments 2 through 4 demonstrate that both age groups can suppress words that are emotional (positive or negative valence) or neutral. The suppression effect also persists even if participants are tested using independent probe words that are semantically related to the target words but were not the studied cue words (Experiments 3 and 4). These data suggest that the cognitive functioning necessary to suppress information from memory is present in older adulthood, and that both emotional and neutral information can be successfully suppressed from memory. PMID:21517183

  9. Dimensional change card sort performance associated with age-related differences in functional connectivity of lateral prefrontal cortex.

    PubMed

    Ezekiel, Fredrick; Bosma, Rachael; Morton, J Bruce

    2013-07-01

    The Dimensional Change Card Sort (DCCS) is a standard procedure for assessing executive functioning early in development. In the task, participants switch from sorting cards one way (e.g., by color) to sorting them a different way (e.g., by shape). Traditional accounts associate age-related changes in DCCS performance with circumscribed changes in lateral prefrontal cortex (lPFC) functioning, but evidence of age-related differences in the modulation of lPFC activity by switching is mixed. The current study therefore tested for possible age-related differences in functional connectivity of lPFC with regions that comprise a larger cognitive control network. Functional magnetic resonance imaging (fMRI) data collected from children and adults performing the DCCS were analyzed by means of independent components analysis (ICA). The analysis revealed several important age-related differences in functional connectivity of lPFC. In particular, lPFC was more strongly connected with the anterior cingulate, inferior parietal cortex, and the ventral tegmental area in adults than in children. Theoretical implications are discussed. PMID:23328350

  10. The alpha-2A noradrenergic receptor agonist guanfacine improves visual object discrimination reversal performance in aged rhesus monkeys.

    PubMed

    Steere, J C; Arnsten, A F

    1997-10-01

    Administration of either low or high doses of the alpha-2A adrenergic agonist guanfacine (GFC) to aged monkeys has been shown to improve performance of the delayed-response task, a task linked to the dorsolateral prefrontal cortex (dlPFC). Monkeys treated with higher guanfacine doses also appeared less disinhibited, suggesting enhanced ventromedial-orbital PFC (vmPFC) function. To test this hypothesis, the current study examined the effects of low versus high doses of GFC on reversal of a visual object discrimination task, a task particularly sensitive to vmPFC lesions. The results of this study showed that high (0.1 mg/kg) but not low (0.00001-0.001 mg/kg) doses of GFC significantly improved reversal performance in aged monkeys. These results may be relevant to GFC's calming effects in attention deficit hyperactivity disorder. PMID:9383511

  11. 'The engine just started coughing!' - Limits of physical performance, aging and career continuity in elite endurance sports.

    PubMed

    Ronkainen, Noora J; Ryba, Tatiana V; Nesti, Mark S

    2013-12-01

    This research examines male endurance athletes' experience of aging and/or reaching the perceived limits of physical performance. More specifically, the current study aimed to explore how existential meanings attached to these experiences are connected with athletes' decision-making concerning career continuity and retirement. Life story interviews were conducted with 10 Finnish runners and/or orienteers aged between 25 and 62 and the data was analyzed with an existential-narrative framework. Four major storylines related to aging were identified: The end of an era, putting things in perspective, the attitude has to change and winning was never the only motive. Our results suggest that endurance athletes possess diverse ways of bringing meaning to the experience of aging, both confirming and resisting the dominant cultural narrative of decline. While three athletes' stories confirmed the normativity of retirement when unable to improve their results anymore, other athletes demonstrated career continuity and positive aspects in the late career years, such as lack of competitive anxiety, finding perspective and increased enjoyment in running. We suggest that through awareness of alternative narratives, sport psychology consultants may be able to help their clients to explore new meanings in the potentially challenging and beneficial experiences of aging and athletic retirement.

  12. Teaching styles of mothers and the match-to-sample performance of their retarded preschool-age- children.

    PubMed

    Filler, J W; Bricker, W A

    1976-03-01

    Twenty-one mothers and their preschool-age retarded children were observed during three structured teaching sessions. Each session was rated for various forms of maternal preresponse and postresponse activity as well as performance of the children. The results indicated that the most frequent forms of maternal behavior were preresponse verbal directions and instructions; however, the best predictor of children's correct performance was postresponse positive feedback. Patterns of intercorrelations among maternal measures were generally consistent with those reported by Hess and Shipman (1965). The hypothesis was advanced that maternal postresponse feedback may occur as the result of correct responding which, in turn, is more directly affected by other aspects of teaching style.

  13. 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.

  14. 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

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

    PubMed

    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, χ(2) /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, χ(2) /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. Improved aging performance of vapor phase deposited hydrophobic self-assembled monolayers

    NASA Astrophysics Data System (ADS)

    Gnanappa, Arun Kumar; O'Murchu, Cian; Slattery, Orla; Peters, Frank; O'Hara, Tony; Aszalós-Kiss, Balázs; Tofail, Syed A. M.

    2011-02-01

    A hydrophobic self-assembled monolayer (SAM) of fluoro-octyl-trichloro-silane (FOTS) was deposited on silicon using a vapor phase technique. The aging of the hydrophobic layer was examined using water contact angle measurements. It has been found that while such monolayer films suffer from a loss of hydrophobicity with time, pre-immersion nitrogen annealing can significantly improve the aging characteristics of these monolayers. The effect of nitrogen annealing on the improved aging properties of SAM coatings has been investigated by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The hydrolytic stability and the effect of nitrogen annealing were studied by morphological evolution during immersion. A spontaneous formation of silane mounds on the surface of the monolayers was found by AFM. These mounds have been irreversibly transformed from initially uniform hydrophobic surface layers. It is highly probable that the compliance of these mounds can reasonably allow hydrophilic sites to be located around the mounds. Interestingly, the density of these mounds formation is very less on the annealed samples. XPS reveals a higher level of coverage by the N2-annealed film due to agglomeration. A relative abundance of CF3 and CF2 moieties in the annealed film may explain the enhancement of the hydrophobicity as revealed by higher level of water contact angle. This hydrophobicity was found to be significantly stable in water. This novel finding explains the improved hydrophobic stability of FOTS monolayers as primarily a morpho-chemical effect that originates from the densification of the monolayers upon annealing.

  17. Effect of age on geriatric depression scale performance in Parkinson's disease.

    PubMed

    Weintraub, Daniel; Saboe, Kirsten; Stern, Matthew B

    2007-07-15

    The purpose of this study was to compare the validity of the 15-item Geriatric Depression Scale (GDS-15) in nonelderly (<65 years), young-elderly (age, 65-75), and old-elderly (>75 years) patients with Parkinson's disease (PD). 57 nonelderly, 88 young-elderly, and 81 old-elderly PD patients were administered the GDS-15 and the Structured Clinical Interview for DSM-IV depression module. Receiver-operating characteristic (ROC) curves were plotted for GDS-15 scores against a DSM-IV diagnosis of major or minor depression. The discriminant validity of the GDS-15 was high for nonelderly, young-elderly, and old-elderly subjects (ROC area under curve = 0.92, 0.91, and 0.95, respectively), with optimal dichotomization at a cut-off of 4/5 (85% sensitivity and 84% specificity in nonelderly; 89% sensitivity and 82% specificity in young-elderly) and 5/6 (90% sensitivity and 90% specificity in old-elderly). In conclusion, the GDS-15 has comparable validity in younger and older PD patients, suggesting its appropriateness as a depression screening instrument in PD patients of all ages.

  18. Age-related changes in deterministic learning from positive versus negative performance feedback.

    PubMed

    van de Vijver, Irene; Ridderinkhof, K Richard; de Wit, Sanne

    2015-01-01

    Feedback-based learning declines with age. Because older adults are generally biased toward positive information ("positivity effect"), learning from positive feedback may be less impaired than learning from negative outcomes. The literature documents mixed results, due possibly to variability between studies in task design. In the current series of studies, we investigated the influence of feedback valence on reinforcement learning in young and older adults. We used nonprobabilistic learning tasks, to more systematically study the effects of feedback magnitude, learning of stimulus-response (S-R) versus stimulus-outcome (S-O) associations, and working-memory capacity. In most experiments, older adults benefitted more from positive than negative feedback, but only with large feedback magnitudes. Positivity effects were pronounced for S-O learning, whereas S-R learning correlated with working-memory capacity in both age groups. These results underline the context dependence of positivity effects in learning and suggest that older adults focus on high gains when these are informative for behavior.

  19. 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.

  20. Cardiac Output and Performance during a Marathon Race in Middle-Aged Recreational Runners

    PubMed Central

    Billat, Véronique L.; Petot, Hélène; Landrain, Morgan; Meilland, Renaud; Koralsztein, Jean Pierre; Mille-Hamard, Laurence

    2012-01-01

    Purpose. Despite the increasing popularity of marathon running, there are no data on the responses of stroke volume (SV) and cardiac output (CO) to exercise in this context. We sought to establish whether marathon performance is associated with the ability to sustain high fractional use of maximal SV and CO (i.e, cardiac endurance) and/or CO, per meter (i.e., cardiac cost). Methods. We measured the SV, heart rate (HR), CO, and running speed of 14 recreational runners in an incremental, maximal laboratory test and then during a real marathon race (mean performance: 3 hr 30 min ± 45 min). Results. Our data revealed that HR, SV and CO were all in a high but submaximal steady state during the marathon (87.0 ± 1.6%, 77.2 ± 2.6%, and 68.7 ± 2.8% of maximal values, respectively). Marathon performance was inversely correlated with an upward drift in the CO/speed ratio (mL of CO × m−1) (r = −0.65, P < 0.01) and positively correlated with the runner's ability to complete the race at a high percentage of the speed at maximal SV (r = 0.83, P < 0.0002). Conclusion. Our results showed that marathon performance is inversely correlated with cardiac cost and positively correlated with cardiac endurance. The CO response could be a benchmark for race performance in recreational marathon runners. PMID:22645458

  1. 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

  2. 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.

  3. 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.

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

    PubMed

    James, Logan S; Sakata, Jon T

    2015-10-01

    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

  5. 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

  6. 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.

  7. Performance as a function of shooting style in basketball players under 11 years of age.

    PubMed

    Arias, José L

    2012-04-01

    Shooting style in basketball refers to the height adopted by a player in holding the ball, specifically the height of the hand and the ball with regard to the line of sight before the final extension of the elbow during a shot. The literature differentiates between a high and a low style. This study analyzed shooting frequency in young boys as a function of style and which shooting style had the highest accuracy and success in real games. Participants were 81 boys from eight basketball teams, aged 9-11 years. The sample consisted of 5,740 standard shots in 56 games. The design was nomotethic, follow-up, and multidimensional. The results indicated that low style predominated over the high style, although overall accuracy and efficacy were better using the high style. Various strategies and practical considerations are suggested for teachers and coaches to focus on teaching the high style.

  8. 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,…

  9. 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…

  10. 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...

  11. 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…

  12. 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.

  13. Success Estimations and Performance in Children as Influenced by Age, Gender, and Task.

    ERIC Educational Resources Information Center

    Lee, Amelia M.; And Others

    1988-01-01

    Randomly assigned 80 boys and girls in grades 3 and 7 to either a football-related or a dance-related group. Performance expectancies obtained prior to engaging in a novel motor task can be affected by the way a task is presented. Boys were more affected than girls by labels of sex appropriateness. (Author/BJV)

  14. 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…

  15. Tennessee's Performance Funding Policy: L'Enfant Terrible of Assessment at Age Eight.

    ERIC Educational Resources Information Center

    Banta, Trudy W.; Fisher, Homer S.

    The paper addresses issues concerned with increasing state interest in encouraging public institutions of higher education to demonstrate educational quality through outcomes assessment and reports on the development and implementation of Tennessee's program of performance funding. Emphasis is on guidelines contained within a 5-year performance…

  16. 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.

  17. Relative age effect and performance in the U16, U18 and U20 European Basketball Championships.

    PubMed

    Arrieta, Haritz; Torres-Unda, Jon; Gil, Susana María; Irazusta, Jon

    2016-08-01

    This study sought to determine the association of relative age and performance of young elite basketball players. The distribution of the birth dates, heights, positions, classification and performance of the male and female participants (n = 2395) of the U16, U18 and U20 European Basketball Championships were analysed. We found an over-representation of players born during the initial months of the year in all groups, with the relative age effect being more evident in players of the U16 and U18 groups, than of the U20 teams, particularly in male squads. Nevertheless, in the U20 championships, those teams that had the oldest players performed the best. In all championships, the oldest participants played more minutes. In addition, relatively older male players scored better in total points and in performance index rating when results were normalised to played time. This effect was not found for female players. Regarding playing position, different distributions of birth dates were observed due to each position's physical requirements. Thus, basketball coaches and managers should keep these results in mind when they select players because if not, they might subject players who are born towards the end of the year to a negative selection bias.

  18. Age and "Type" of Domain Specific Entry Qualifications as Predictors of Student Nurses' Performance in Biological, Social and Behavioural Sciences in Nursing Assessments.

    ERIC Educational Resources Information Center

    Ofori, Richard

    2000-01-01

    A study of 222 nursing students in England found no significant differences in performance in the sciences among those with different educational qualifications. Age was a better predictor of science performance. (SK)

  19. Aberrant functional connectivity in Papez circuit correlates with memory performance in cognitively intact middle-aged APOE4 carriers.

    PubMed

    Li, Wenjun; Antuono, Piero G; Xie, Chunming; Chen, Gang; Jones, Jennifer L; Ward, B Douglas; Singh, Suraj P; Franczak, Malgorzata B; Goveas, Joseph S; Li, Shi-Jiang

    2014-08-01

    The main objective of this study is to detect the early changes in resting-state Papez circuit functional connectivity using the hippocampus as the seed, and to determine the associations between altered functional connectivity (FC) and the episodic memory performance in cognitively intact middle-aged apolipoprotein E4 (APOE4) carriers who are at risk of Alzheimer's disease (AD). Forty-six cognitively intact, middle-aged participants, including 20 APOE4 carriers and 26 age-, sex-, and education-matched noncarriers were studied. The resting-state FC of the hippocampus (HFC) was compared between APOE4 carriers and noncarriers. APOE4 carriers showed significantly decreased FC in brain areas that involve learning and memory functions, including the frontal, cingulate, thalamus and basal ganglia regions. Multiple linear regression analysis showed significant correlations between HFC and the episodic memory performance. Conjunction analysis between neural correlates of memory and altered HFC showed the overlapping regions, especially the subcortical regions such as thalamus, caudate nucleus, and cingulate cortices involved in the Papez circuit. Thus, changes in connectivity in the Papez circuit may be used as an early risk detection for AD.

  20. Corrosion performance of a nickel-molybdenum-chromium alloy: Effects of aging, alloying elements, and electrolyte composition

    SciTech Connect

    Rebak, R.B.; Srivastava, S.K.

    1999-04-01

    General and stress corrosion cracking (SCC) behaviors of a Ni-Mo-Cr alloy were assessed in the mill-annealed and aged conditions. Performance of this Ni-25% Mo-8% Cr alloy (alloy 242 [proposed UNS N10242]) was compared to the performance of a Ni-Mo alloy (alloy B-3 [UNS N10675]) and a Ni-Cr-Mo alloy (C-2000 [UNS N06200]). Results showed the general corrosion rate of alloy 242 in reducing acids was slightly higher than that of alloy B-3. However, in mildly oxidizing conditions, the corrosion rate of alloy 242 was lower than that of alloy B-3. Effects of electrolyte and alloy composition on the general corrosion rate were studied. After aging at 650 C (1,200 F) for 24 h, the corrosion rate of alloy 242 increased slightly, particularly in strongly reducing conditions. Alloy 242 was resistant to SCC but was prone to hydrogen-induced cracking, especially in the aged condition.

  1. 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,…).

  2. An age apart: the effects of intergenerational contact and stereotype threat on performance and intergroup bias.

    PubMed

    Abrams, Dominic; Eller, Anja; Bryant, Jacqueline

    2006-12-01

    An experimental study examined the effect of intergenerational contact and stereotype threat on older people's cognitive performance, anxiety, intergroup bias, and identification. Participants completed a series of cognitive tasks under high or low stereotype threat (through comparison with younger people). In line with stereotype threat theory, threat resulted in worse performance. However, this did not occur if prior intergenerational contact had been more positive. This moderating effect of contact was mediated by test-related anxiety. In line with intergroup contact theory, more positive contact was associated with reduced prejudice and reduced ingroup identification. However this occurred in the high threat, but not low threat, condition. The findings suggest that positive intergenerational contact can reduce vulnerability to stereotype threat among older people.

  3. 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. PMID:13679229

  4. Assessing the Impact of Equipment Aging on System Performance Using Simulation Modeling Methods

    SciTech Connect

    Gupta, N. K.

    2005-11-07

    The radiological Inductively Coupled Plasma Mass Spectrometer (ICP-MS) is used to analyze the radioactive samples collected from different radioactive material processing operations at Savannah River Site (SRS). The expeditious processing of these samples is important for safe and reliable operations at SRS. As the radiological (RAD) ICP-MS machine ages, the experience shows that replacement parts and repairs are difficult to obtain on time for reliable operations after 5 years of service. A discrete event model using commercial software EXTEND was prepared to assess the impact on sample turn around times as the ICP-MS gets older. The model was prepared using the sample statistics from the previous 4 years. Machine utilization rates were calculated for the new machine, 5 year old machine, 10 year old machine, and a 12 year old machine. Computer simulations were run for these periods and the sample delay times calculated. The model was validated against the sample statistics collected from the previous 4 quarters. 90% confidence intervals were calculated for the 10th, 25th, 50th, and 90th quantiles of the samples. The simulation results show that if 50% of the samples are needed on time for efficient site operations, a 10 year old machine could take nearly 50 days longer to process these samples than a 5-year old machine. This simulation effort quantifies the impact on sample turn around time as the ICP-MS gets older.

  5. 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

  6. 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.

  7. Time reproduction performance is associated with age and working memory in high-functioning youth with autism spectrum disorder.

    PubMed

    Brenner, Laurie A; Shih, Vivian H; Colich, Natalie L; Sugar, Catherine A; Bearden, Carrie E; Dapretto, Mirella

    2015-02-01

    Impaired temporal processing has historically been viewed as a hallmark feature of attention deficit hyperactivity disorder. Recent evidence suggests temporal processing deficits may also be characteristic of autism spectrum disorder (ASD). However, little is known about the factors that impact temporal processing in children with ASD. The purpose of this study was to assess the effects of co-morbid attention problems, working memory (WM), age, and their interactions, on time reproduction in youth with and without ASD. Twenty-seven high-functioning individuals with ASD and 25 demographically comparable typically developing individuals (ages 9-17; 85% male) were assessed on measures of time reproduction, auditory WM, and inattention/hyperactivity. The time reproduction task required depression of a computer key to mimic interval durations of 4, 8, 12, 16, or 20 sec. Mixed effects regression analyses were used to model accuracy and variability of time reproduction as functions of diagnostic group, interval duration, age, WM, and inattention/hyperactivity. A significant group by age interaction was detected for accuracy, with the deficit in the ASD group being greater in younger children. There was a significant group by WM interaction for consistency, with the effects of poor WM on performance consistency being more pronounced in youth with ASD. All participants tended to underestimate longer interval durations and to be less consistent for shorter interval durations; these effects appeared more pronounced in those who were younger or who had poorer WM performance. Inattention/hyperactivity symptoms in the ASD group were not related to either accuracy or consistency. This study highlights the potential value of temporal processing as an intermediate trait of relevance to multiple neurodevelopmental disorders. PMID:25078724

  8. 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.

  9. 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.

  10. Hunting behaviour and breeding performance of northern goshawks Accipiter gentilis, in relation to resource availability, sex, age and morphology.

    PubMed

    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. PMID:23995242

  11. 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.

  12. 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.

  13. The relative age effect in the German Football TID Programme: biases in motor performance diagnostics and effects on single motor abilities and skills in groups of selected players.

    PubMed

    Votteler, Andreas; Höner, Oliver

    2014-01-01

    This study examined the disturbing effects of relative age on the talent identification process in the talent development programme of the German Football Association. The bias in the selection rate was examined via the extent of relative age effects. The bias in motor performance diagnostics was analysed by comparing the motor performance of selected players with normal motor development. The mechanisms underlying the relative age biases in motor performance were examined by modelling the direct and indirect effects of relative age on single motor performance tests for sprint, running agility, dribbling and ball passing and control. Data from 10,130 selected football players from the U12 to U15 age groups were collected in autumn 2010. The birth distribution differed significantly from the reference population with approximately 61% of the players born in the first half of the year. The selection probability was approximately two times higher for players born in the first quarter of the year than for players born in the last quarter. Revised motor performance diagnostics showed better results on average for relatively younger players. Path analysis revealed significant direct and indirect relative age effects for physiologically demanding tests and almost no effects for technically demanding tests. Large sample sizes allowed high resolution in relative age with additional informational content and multivariate modelling of the complex relationships among relative age, physical development and motor performance. The results are discussed on how relative age affects the effectiveness and fairness of talent identification and development processes.

  14. 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.

  15. Rhesus Factor Modulation of Effects of Smoking and Age on Psychomotor Performance, Intelligence, Personality Profile, and Health in Czech Soldiers

    PubMed Central

    Flegr, Jaroslav; Geryk, Jan; Volný, Jindra; Klose, Jiří; Černochová, Dana

    2012-01-01

    Background Rhesus-positive and rhesus-negative persons differ in the presence-absence of highly immunogenic RhD protein on the erythrocyte membrane. This protein is a component of NH3 or CO2 pump whose physiological role is unknown. Several recent studies have shown that RhD positivity protects against effects of latent toxoplasmosis on motor performance and personality. It is not known, however, whether the RhD phenotype modifies exclusively the response of the body to toxoplasmosis or whether it also influences effects of other factors. Methodology/Principal Findings In the present cohort study, we searched for the effects of age and smoking on performance, intelligence, personality and self-estimated health and wellness in about 3800 draftees. We found that the positive effect of age on performance and intelligence was stronger in RhD-positive soldiers, while the negative effect of smoking on performance and intelligence was of similar size regardless of the RhD phenotype. The effect of age on four Cattell's personality factors, i.e., dominance (E), radicalism (Q1), self-sentiment integration (Q3), and ergic tension (Q4), and on Cloninger's factor reward dependency (RD) was stronger for RhD-negative than RhD-positive subjects, while the effect of smoking on the number of viral and bacterial diseases was about three times stronger for RhD-negative than RhD-positive subjects. Conclusions RhD phenotype modulates the influence not only of latent toxoplasmosis, but also of at least two other potentially detrimental factors, age and smoking, on human behavior and physiology. The negative effect of smoking on health (estimated on the basis of the self-rated number of common viral and bacterial diseases in the past year) was much stronger in RhD-negative than RhD-positive subjects. It is critically needed to confirm the differences in health response to smoking between RhD-positive and RhD-negative subjects by objective medical examination in future studies. PMID

  16. 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

  17. Especial skill effect across age and performance level: the nature and degree of generalization.

    PubMed

    Czyż, S H; Breslin, G; Kwon, O; Mazur, M; Kobiałka, K; Pizlo, Z

    2013-01-01

    It has been claimed that an especial skill emerges after massive amounts of basketball practice. Despite this no direct evidence is available to support this claim. The authors aimed to shed light on this question. Thirty-seven male basketball players took part representing four groups: 2 groups of senior players, a cadet group, and a group of juniors. Players performed free throw shots from 7 distances including shots from the free throw line (15 ft). It was shown that an especial skill was present in senior players, but not in junior players who had only 3 years of playing experience. The authors present a descriptive model of especial skill and express it using the formalism of a hierarchical Bayesian model to fit the data and estimate the parameters. This model can account not only for the results, which indicate the presence and a substantial degree of generalizability of especial skill to nearby distances, but also for results of the original study on especial skill where it was proposed that specificity in practice leads to the emergence of the especial skill.

  18. 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.

  19. 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.

  20. 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. PMID:26833033

  1. 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.

  2. Cross-sectional versus longitudinal age gradients of tower of Hanoi performance: the role of practice effects and cohort differences in education.

    PubMed

    Rönnlund, Michael; Lövdén, Martin; Nilsson, Lars-Göran

    2008-01-01

    We examined 5-year longitudinal changes in Tower of Hanoi (TOH) performance in a population-based sample of adults (35-85 years initially; n = 1480). An age-matched sample (n = 433) was included to estimate practice effects. The longitudinal age gradients differed substantially from the cross-sectional age gradients. This was the case even when practice effects, that were substantial in magnitude across the young/middle-aged groups, were controlled for. Instead of a continuous age-related deficit in performance from 35 and onwards, longitudinal data showed slowing of performance and increases of illegal moves past age 65. Cohort-related differences in educational attainment did not account for this discrepancy. Further analyses revealed a positive relation between practice-related gains and explicit memory of having performed the task at the first test occasion and a positive association between latent changes in TOH and Block Design, in line with cross-sectional findings. In conclusion, the results demonstrate a pattern of age-related changes indicating a late-onset decline of TOH performance and underscore the need to control for retest effects in longitudinal aging research. PMID:17924234

  3. Performance of an HRP-2 Rapid Diagnostic Test in Nigerian Children Less Than 5 Years of Age

    PubMed Central

    Ajumobi, Olufemi; Sabitu, Kabir; Nguku, Patrick; Kwaga, Jacob; Ntadom, Godwin; Gitta, Sheba; Elizeus, Rutebemberwa; Oyibo, Wellington; Nsubuga, Peter; Maire, Mark; Poggensee, Gabriele

    2015-01-01

    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. PMID:25711608

  4. Electrically evoked and voluntary maximal isometric tension in relation to dynamic muscle performance in elderly male subjects, aged 69 years.

    PubMed

    Davies, C T; White, M J; Young, K

    1983-01-01

    The dynamic performance and electrically evoked mechanical properties of elderly triceps surae muscle have been investigated in 9 men, aged 69 yr. Dynamic performance consisted of cycling on a force bicycle and a vertical jump off two feet from a force platform. The results showed that the time to peak tension (TPT) and half relaxation time (1/2 RT) were significantly greater (p less than 0.001) by 30 ms and 22 ms and the supramaximal twitch (Pt) and tetanic (20 Hz-P020) tensions and maximal voluntary contraction (MVC) were less by 45 N (-33%), 708 N (-49%), and 899 N (-43%) in the elderly compared with young male control subjects. On the force platform, the height jumped (Ht), maximal force exerted (P), take-off velocity (VT), net impulse (NI) and peak power output (W) were less by 18.6 cm, 173 N, 0.9 ms-1, 52 Ns and 1120 w respectively. Similar differences of power, force and velocity were observed on the force bicycle. The reduction of W in the elderly was associated with the contractile characteristics of the leg muscle. The loss of contractile speed and capacity to to generate force in old people was reflected in their inability to develop power during the performance of a maximal vertical jump and cycling.

  5. The Influence of Age of Onset and Acute Anabolic Steroid Exposure on Cognitive Performance, Impulsivity, and Aggression in Men

    PubMed Central

    Hildebrandt, Tom; Langenbucher, James W.; Flores, Adrianne; Harty, Seth; Berlin, Heather A.

    2014-01-01

    A growing translational literature suggests that adolescent exposure to anabolic-androgenic steroids (AASs) leads to increased aggression and impulsivity. However, little is known about the cognitive effects of AASs among AAS users or the differences between adolescent and adult onset users. This study provides a test of the effects of acute naturalistic AAS use and age of onset (adolescent vs. adult) on measures of inhibitory control, planning and attention, and decision making. Seventy one active adult male AAS uses completed self-report measures of impulsivity and aggress and a subsample (11 adolescent onset vs. 11 adult onset) matched on current age were administered four computerized test from the CANTAB battery and the Iowa Gambling Task. Multiple regression analyses and a series of 2 (Adolescent vs. Adult) X 2 (On-cycle vs. Off-cycle) analyses of variance (ANOVAs) were used to examine the differential effects of age of onset and acute drug use on cognition and behavior. Regression analyses revealed larger on-cycle effects for adolescent users than adult users. Subsample analyses indicated that on-cycle users performed less well on cognitive measures of inhibitory control and attention, but not on tests of planning or decision making. Adolescent onset was associated with a greater impulsivity and a greater acute sensitivity to AAS effects on attention. These preliminary findings suggest the possibility that acute AAS use is associated with some differences in inhibitory control and impulsivity and to a lesser degree aggression. These effects may be more potent for those initiating AAS use in adolescence. PMID:24841181

  6. The effects of unilateral grab rail assistance on the sit-to-stand performance of older aged adults.

    PubMed

    O'Meara, Damien M; Smith, Richard M

    2006-04-01

    This study investigated the effects of unilateral grab rail assistance during the sit-to-stand transfer to develop an understanding of lower limb joint mechanics and whole body movement patterns. External reaction forces at the grab rail and floor interfaces were also investigated to understand the nature of the assistance provided by the introduction of unilateral upper body assistance. While 12 older aged adults performed the sit-to-stand, three-dimensional body segment kinematics were recorded to determine lower body joint motion and whole body centre of mass motion. Grab rail reaction forces and bilateral ground reaction forces were recorded to determine external reaction forces and lower body joint kinetics. Grab rail assisted conditions were compared with unassisted transfers. During grab rail assistance, a systematic asymmetry was introduced to lower limb joint kinetics, without noticeable alterations to peak lower body joint motion and whole body movement patterns. Ipsilateral net joint moments and powers decreased in the ankle and hip and increased in the knee, while the contralateral net joint moments and powers increased in the hip and decreased in the knee. Joint kinetic and kinematic responses suggest a motor control strategy that maintains symmetric sit-to-stand movement patterns by adjusting bilateral muscle control when a unilateral external reaction force is provided. Understanding the mechanical assistance that is generated during the sit-to-stand will facilitate optimal design of grab rails for older aged adults and may contribute to design for specific pathologies. Such design implementation will influence the ability of older aged adults to remain independent in the community.

  7. Radiotherapy with or without temozolomide in elderly patients aged ≥ 70 years with glioblastoma

    PubMed Central

    Karaoglanoglu, Ozden; Akyazici, Emine

    2016-01-01

    Introduction Although the recommended optimal treatment of glioblastoma multiforme (GBM) is adjuvant chemoradiotherapy, trials in GBM have excluded patients older than 70 years. In this study, we aimed to assess overall survival (OS) and prognostic factors in elderly patients (≥ 70 years) with newly diagnosed GBM treated with radiotherapy (RT) ± concurrent/adjuvant temozolomide (TMZ). Material and methods Inclusion criteria were patients ≥ 70 years, pre-RT Karnofsky performance status (KPS) ≥ 60, and time between diagnosis and start of RT ≤ 2 months. A total of 40 patients aged ≥ 70 years, 12 female and 28 male, treated between January 2004 and December 2012, were evaluated. Median age was 73.5 years (range, 70–83 years). The median RT dose was 60 Gy (range, 30–62 Gy). Twenty-one (52.5%) received concurrent TMZ, and of those 12 (30%) went on to receive adjuvant TMZ. Results The median OS was 7 months (95% CI: 5.45–8.54). One- and two-year OS for the whole cohort was 38% and 16%, respectively. Sex, type of surgery, tumor size, and RT dose did not significantly affect the OS. Presence of concurrent TMZ (p < 0.005) and presence of adjuvant TMZ (p < 0.001) were associated with longer OS in our cohort. Conclusions RT ± TMZ seems to be a well-tolerated treatment in patients ≥ 70 years with GBM. Even though no superiority was found between conventional or hypofractionated RT regimens (p = 0.405), the addition of concurrent and adjuvant TMZ to RT increased the OS in our study.

  8. Radiotherapy with or without temozolomide in elderly patients aged ≥ 70 years with glioblastoma

    PubMed Central

    Karaoglanoglu, Ozden; Akyazici, Emine

    2016-01-01

    Introduction Although the recommended optimal treatment of glioblastoma multiforme (GBM) is adjuvant chemoradiotherapy, trials in GBM have excluded patients older than 70 years. In this study, we aimed to assess overall survival (OS) and prognostic factors in elderly patients (≥ 70 years) with newly diagnosed GBM treated with radiotherapy (RT) ± concurrent/adjuvant temozolomide (TMZ). Material and methods Inclusion criteria were patients ≥ 70 years, pre-RT Karnofsky performance status (KPS) ≥ 60, and time between diagnosis and start of RT ≤ 2 months. A total of 40 patients aged ≥ 70 years, 12 female and 28 male, treated between January 2004 and December 2012, were evaluated. Median age was 73.5 years (range, 70–83 years). The median RT dose was 60 Gy (range, 30–62 Gy). Twenty-one (52.5%) received concurrent TMZ, and of those 12 (30%) went on to receive adjuvant TMZ. Results The median OS was 7 months (95% CI: 5.45–8.54). One- and two-year OS for the whole cohort was 38% and 16%, respectively. Sex, type of surgery, tumor size, and RT dose did not significantly affect the OS. Presence of concurrent TMZ (p < 0.005) and presence of adjuvant TMZ (p < 0.001) were associated with longer OS in our cohort. Conclusions RT ± TMZ seems to be a well-tolerated treatment in patients ≥ 70 years with GBM. Even though no superiority was found between conventional or hypofractionated RT regimens (p = 0.405), the addition of concurrent and adjuvant TMZ to RT increased the OS in our study. PMID:27647990

  9. 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.

  10. 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.

  11. Age and gender differences in half-Ironman triathlon performances – the Ironman 70.3 Switzerland from 2007 to 2010

    PubMed Central

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

    2012-01-01

    Background To date, the age-related decline and gender differences in performance have been investigated for both Olympic and Ironman distance triathlons, but not for the intermediate distance (ie, the half-Ironman distance triathlon covering 1.9 km swimming, 90 km cycling and 21.1 km running, Ironman 70.3®). We determined the age-related differences in performance and the gender differences for female and male half-Ironman triathletes of 6303 finishers (1115 women and 5188 men) at the Ironman 70.3 Switzerland in Rapperswil, Switzerland, from 2007 to 2010. Methods Analyses of variance were used to examine performance trends and differences between the genders. Results Gender differences in total event time were affected by age (F = 4.2; P < 0.001). Women achieved their best performance between 25 and 39 years whereas men attained their fastest race times between 18 and 39 years. The gender difference for ages 18–24 years was significantly (P < 0.01) greater compared to older age groups (25–29 years and 40–44 years), and the gender difference for age groups 45–49 years and 50–54 years was significantly (P < 0.01) greater than for those between the ages of 35–39 years. Conclusion The present data suggest that the fastest race time in a half-Ironman triathlon was achieved between the age of 25 and 39 years for women and between 18 and 39 years for men. Further studies considering the influences on endurance performance are required to better understand the age and gender interactions in half-Ironman triathlon performances, and these studies may provide valuable information to delineate the difference in performance between female and male half-Ironman triathletes. PMID:24198588

  12. Age-related site-specific muscle loss in the thigh and zigzag walking performance in older men and women.

    PubMed

    Abe, Takashi; Loenneke, J P; Thiebaud, R S; Ogawa, M; Mitsukawa, N

    2014-12-01

    To investigate the relationships between site-specific muscle loss in the thigh, muscle quality and zigzag walking performance, 40 men and 41 women aged 65-79 years had muscle thickness (MTH) measured by ultrasound at nine sites on the anterior and posterior aspects of the body. Skeletal muscle mass (SM) was estimated from an ultrasound-derived prediction equation. Site-specific thigh sarcopenia was calculated using ultrasound-measured MTH at the anterior/posterior aspects of the thigh (AP-MTH ratio). Zigzag walking time (ZWT) and maximum isometric knee extension (KE) and flexion (KF) torques were measured. Muscle quality (torque/thigh SM) and knee joint strength index (torque/body mass) were calculated. There were no significant correlations between SM index and ZWT. However, AP-MTH ratio was inversely correlated (P < 0.05) to ZWT in men (r = -0.335) and women (r = -0.309). ZWT was also inversely correlated (P < 0.05) to KE-strength index in both sexes (men, r = -0.328; women, r = -0.372). Similarly, ZWT was correlated to KF-strength index (r = -0.497) and muscle quality (r = -0.322) in women, but not in men. After adjusting for age, height and body mass, AP-MTH ratio was inversely correlated to ZWT in men (r = -0.325) and tended to be correlated to ZWT in women (r = -0.263). Zigzag walking performance may be associated with site-specific thigh sarcopenia in older men and women.

  13. Age and gender dependent heart rate circadian model development and performance verification on the proarrhythmic drug case study

    PubMed Central

    2013-01-01

    Background There are two main reasons for drug withdrawals at the various levels of the development path – hepatic and cardiac toxicity. The latter one is mainly connected with the proarrhythmic potency and according to the present practice is supposed to be recognized at the pre-clinical (in vitro and animal in vivo) or clinical level (human in vivo studies). There are, although, some limitations to all the above mentioned methods which have led to novel in vitro – in vivo extrapolation methods being introduced. With the use of in silico implemented mathematical and statistical modelling it is possible to translate the in vitro findings into the human in vivo situation at the population level. Human physiology is influenced by many parameters and one of them which needs to be properly accounted for is a heart rate which follows the circadian rhythm. We described such phenomenon statistically which enabled the improved assessment of the drug proarrhythmic potency. Methods A publicly available data set describing the circadian changes of the heart rate of 18 healthy subjects, 5 males (average age 36, range 26–45) and 13 females (average age 34, range 20–50) was used for the heart rate model development. External validation was done with the use of a clinical research database containing heart rate measurements derived from 67 healthy subjects, 34 males and 33 females (average age 33, range 17–72). The developed heart rate model was then incorporated into the ToxComp platform to simulate the impact of circadian variation in the heart rate on QTc interval. The usability of the combined models was assessed with moxifloxacin (MOXI) as a model drug. Results The developed heart rate model fitted well, both to the training data set (RMSE = 128 ms and MAPE = 12.3%) and the validation data set (RMSE = 165 ms and MAPE = 17.1%). Simulations performed at the population level proved that the combination of the IVIVE platform and the population variability description

  14. 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

  15. Age and gender diversity as determinants of performance and health in a public organization: the role of task complexity and group size.

    PubMed

    Wegge, Jürgen; Roth, Carla; Neubach, Barbara; Schmidt, Klaus-Helmut; Kanfer, Ruth

    2008-11-01

    The influence of age and gender composition on group performance and self-reported health disorders was examined with data from 4,538 federal tax employees working in 222 natural work unit groups. As hypothesized, age diversity correlated positively with performance only in groups solving complex decision-making tasks, and this finding was replicated when analyzing performance data collected 1 year later. Age diversity was also positively correlated with health disorders--but only in groups working on routine decision-making tasks. Gender composition also had a significant effect on group performance, such that groups with a high proportion of female employees performed worse and reported more health disorders than did gender-diverse teams. As expected, effects of gender composition were most pronounced in large groups. Effects of age diversity were found when controlling for gender diversity and vice versa. Thus, age and gender diversity seem to play a unique role in performance and well-being. The moderating role of task complexity for both effects of age diversity and the moderating role of group size for both effects of gender diversity further suggest that the impact of these 2 variables depends on different group processes (e.g., knowledge exchange, variation in gender salience).

  16. Frequency-effect of playing screen golf on body composition and golf performance in middle-aged men.

    PubMed

    Jang, Jung-Hoon; Jee, Yong-Seok; Oh, Hye-Won

    2014-10-01

    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.

  17. 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

  18. The relative utility of health-related fitness tests and skilled motor performance tests as measures of biological age in Japanese men.

    PubMed

    Lee, M S; Tanaka, K; Nakagaichi, M; Nakadomo, F; Watanabe, K; Takeshima, N; Hiyama, T; Chodzko-Zaiko, W

    1996-05-01

    In the present paper we report the results of a study in which we compared 2 different approaches to the computation of biological age (BA) in a sample of 322 Japanese men (age range 20 to 79 years). In the first approach, 4 commonly used measures of health-related fitness (VO2peak, trunk flexion from a standing position, body fat, and grip strength) were reduced to a single BA score (HRF Age) using principal component analysis. In contrast, in the second approach, 3 commonly used measures of skilled motor performance and agility (vertical jump, stepping side-to-side, and balancing on one leg with eyes closed) were reduced to a single BA score (SMP Age) using similar multivariate procedures. The criterion-related validity of both of the BA measures was examined by assessing each measure's ability to discriminate between healthy and active groups of subjects. This was achieved by classifying the original subject pool into regularly active (ACT; n = 108) and healthy (HLTH; n = 169) subgroups on the basis of self-reported activity levels. Analyses revealed that HRF Age was a more powerful discriminator between the two activity groups than SMP Age. While HRF Age of HLTH subjects was very close to their chronological age (CA), in the ACT group, HRF Age was on average 15 years less than their CA (P < 0.05). In a separate analysis, we assessed the HRF Age of patients with ischemic heart disease, hypertension, obesity, or diabetes (PAT; n = 45). The HRF Age of these subjects averaged 10 years above their CA. Our data suggest that commonly used measures of health-related fitness can be usefully employed as indices of BA which differentiate between individuals of similar ages but differing health and physical activity status. In contrast, measures of skilled motor performance were found to be less valuable measures of BA. The implication of our findings for future experimental design in exercise and aging research is discussed.

  19. Elevated plus-maze performance of Fischer-344 rats as a function of age and of exposure to 56Fe particles

    NASA Astrophysics Data System (ADS)

    Rabin, Bernard M.; Carrihill-Knoll, Kirsty L.; Carey, Amanda N.; Shukitt-Hale, Barbara; Joseph, James A.; Foster, Brian C.

    The aging process is characterized by a series of changes in neurochemical functioning and in motor and cognitive performance. In addition to changes in cognitive/behavioral performance, aged rats also show an increase in baseline anxiety measured using the elevated plus-maze. Exposure to 56Fe particles, a component of cosmic rays, produces neurochemical and behavioral changes in young animals which are characteristic of aged organisms. The present study was designed to determine the relationships between aging and exposure to 56Fe particles on anxiety. Fischer-344 (F-344), which were 2, 7, 12, and 16 months of age at the time of irradiation, were exposed to 56Fe particles (50 200 cGy). Concordant with previous results, the oldest rats spent less time exploring the open arms of the maze. Exposure to 56Fe particles also produced decreased exploration of the open arms of the plus-maze. The dose needed to produce increased levels of anxiety was a function of age at the time of irradiation. The dose of 56Fe particles needed to produce a decrease in open arm exploration was significantly lower in the rats that were irradiated at 7 and 12 months of age than in the rats irradiated at 2 months of age. These results suggest the possibility that exposing middle-aged astronauts to cosmic rays during exploratory class missions outside the magnetosphere, and the resultant effects on exploration-induced anxiety, may affect their ability to successfully complete mission requirements.

  20. 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

  1. 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

  2. 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 L.

    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…

  3. 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.

  4. Prenatal and childhood growth and physical performance in old age--findings from the Helsinki Birth Cohort Study 1934-1944.

    PubMed

    Eriksson, Johan G; Osmond, Clive; Perälä, Mia-Maria; Salonen, Minna K; Simonen, Mika; Pohjolainen, Pertti; Kajantie, Eero; Rantanen, Taina; von Bonsdorff, Mikaela B

    2015-12-01

    Health in adulthood is in part a consequence of development and growth taking place during sensitive periods in early life. It has not been explored previously whether early growth is associated with physical performance in old age from a life course perspective taking into account health-related behavior, biological risk factors, and early life experiences. At a mean age of 71 years, physical performance was assessed using the Senior Fitness Test (SFT) in 1078 individuals belonging to the Helsinki Birth Cohort Study. We used multiple linear regression analysis to assess the association between the SFT physical fitness scores and individual life course measurements. Several adult characteristics were associated with physical performance including socioeconomic status, lifestyle factors, and adult anthropometry. Higher birth weight and length were associated with better physical performance, even after adjusting for potential confounders (all p values <0.05). The strongest individual association between life course measurements and physical performance in old age was found for adult body fat percentage. However, prenatal growth was independently associated with physical performance seven decades later. These findings suggest that physical performance in old age is at least partly programmed in early life.

  5. Prenatal and childhood growth and physical performance in old age--findings from the Helsinki Birth Cohort Study 1934-1944.

    PubMed

    Eriksson, Johan G; Osmond, Clive; Perälä, Mia-Maria; Salonen, Minna K; Simonen, Mika; Pohjolainen, Pertti; Kajantie, Eero; Rantanen, Taina; von Bonsdorff, Mikaela B

    2015-12-01

    Health in adulthood is in part a consequence of development and growth taking place during sensitive periods in early life. It has not been explored previously whether early growth is associated with physical performance in old age from a life course perspective taking into account health-related behavior, biological risk factors, and early life experiences. At a mean age of 71 years, physical performance was assessed using the Senior Fitness Test (SFT) in 1078 individuals belonging to the Helsinki Birth Cohort Study. We used multiple linear regression analysis to assess the association between the SFT physical fitness scores and individual life course measurements. Several adult characteristics were associated with physical performance including socioeconomic status, lifestyle factors, and adult anthropometry. Higher birth weight and length were associated with better physical performance, even after adjusting for potential confounders (all p values <0.05). The strongest individual association between life course measurements and physical performance in old age was found for adult body fat percentage. However, prenatal growth was independently associated with physical performance seven decades later. These findings suggest that physical performance in old age is at least partly programmed in early life. PMID:26499818

  6. Effects of 6/85-strain Mycoplasma gallisepticum inoculation alone at 10 weeks of age or in conjunction with F-strain Mycoplasma gallisepticum inoculation overlays at 22 or 45 weeks of age on the performance of commercial ....

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of 6/85-strain M. gallisepticum (6/85MG) inoculation alone or in conjunction with a F-strain M. gallisepticum (FMG) over-lay and its timing on the performance of commercial egg laying hens were investigated. Control birds received sham inoculations at 10 wk of age. A second treated gro...

  7. Early life hormetic treatments decrease irradiation-induced oxidative damage, increase longevity, and enhance sexual performance during old age in the Caribbean fruit fly.

    PubMed

    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

  8. 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

  9. Trying to Put the Puzzle Together: Age and Performance Level Modulate the Neural Response to Increasing Task Load within Left Rostral Prefrontal Cortex.

    PubMed

    Bauer, Eva; Sammer, Gebhard; Toepper, Max

    2015-01-01

    Age-related working memory decline is associated with functional cerebral changes within prefrontal cortex (PFC). Kind and meaning of these changes are heavily discussed since they depend on performance level and task load. Hence, we investigated the effects of age, performance level, and load on spatial working memory retrieval-related brain activation in different subregions of the PFC. 19 younger (Y) and 21 older (O) adults who were further subdivided into high performers (HP) and low performers (LP) performed a modified version of the Corsi Block-Tapping test during fMRI. Brain data was analyzed by a 4 (groups: YHP, OHP, YLP, and OLP) × 3 (load levels: loads 4, 5, and 6) ANOVA. Results revealed significant group × load interaction effects within rostral dorsolateral and ventrolateral PFC. YHP showed a flexible neural upregulation with increasing load, whereas YLP reached a resource ceiling at a moderate load level. OHP showed a similar (though less intense) pattern as YHP and may have compensated age-effects at high task load. OLP showed neural inefficiency at low and no upregulation at higher load. Our findings highlight the relevance of age and performance level for load-dependent activation within rostral PFC. Results are discussed in the context of the compensation-related utilization of neural circuits hypothesis (CRUNCH) and functional PFC organization.

  10. Effects of calf weaning age and subsequent management system on growth and reproductive performance of beef heifers.

    PubMed

    Moriel, P; Johnson, S E; Vendramini, J M B; Mercadante, V R G; Hersom, M J; Arthington, J D

    2014-07-01

    Brahman × British crossbred heifers (n = 40 and 38 heifers in yr 1 and 2, respectively) were used to evaluate the effects of calf weaning age and subsequent management system on growth and reproductive performance. On d 0, heifers were ranked by BW (89 ± 16 kg) and age (72 ± 13 d) and randomly assigned to a conventional management group that was normally weaned on d 180 (NW; n = 10 heifers annually) or early weaned (EW) on d 0 and 1) limit fed a high-concentrate diet at 3.5% of BW (as fed) in drylot until d 180 (EW180; n = 10 heifers annually), 2) limit fed a high-concentrate diet at 3.5% of BW (as fed) in drylot until d 90, then grazed on Bahiagrass pastures until d 180 (EW90; n = 10 heifers annually), or 3) grazed on annual ryegrass pastures until d 60 (yr 1; n = 10 heifers) or 90 (yr 2; n = 8 heifers), then on Bahiagrass pastures until d 180 (EWRG). On d 180, all heifers were grouped by treatment and rotated on Bahiagrass pastures until d 390. Grazing heifers were supplemented at 1.0% BW until d 180 and at 1.5% BW from d 180 to 390. From d 0 to 90, EW180 and EW90 heifers were heavier (P ≤ 0.02) than NW and EWRG heifers, whereas NW heifers tended (P = 0.09) to be heavier on d 90 than EWRG heifers. In yr 1 and 2, EW180 heifers were heaviest (P < 0.0001) on d 180. In yr 1, EWRG heifers were lightest (P < 0.0001), whereas EW90 and NW heifers had similar BW (P = 0.58). Conversely, EW90, EWRG, and NW heifers achieved similar BW on d 180 of yr 2 (P ≥ 0.18). Positive correlations were detected (P ≤ 0.05) between liver IGF-1 mRNA abundance on d 90 and ADG from d 0 to 90 and between liver IGF-1 mRNA abundance on d 180 and ADG from d 90 to 180. The EW180 heifers were youngest (P ≤ 0.01) at puberty. From d 260 to 340, the percentage of pubertal heifers was greater (P ≤ 0.03) for EW90 vs. NW heifers but did not differ (P ≥ 0.15) between EWRG and NW heifers. The ADG from d 0 to 90 and the plasma IGF-1 on d 90 and 180 explained approximately 34% of the

  11. 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…

  12. Individual Differences in Language Performance after Cochlear Implantation at One to Three Years of Age: Child, Family, and Linguistic Factors

    ERIC Educational Resources Information Center

    Spencer, Patricia E.

    2004-01-01

    Language skills were investigated in a multicultural sample of 13 prelingually deaf children (11 profoundly deaf from birth) who received cochlear implants between 14 and 38 months of age; average duration of implant use was 49 months. Individual post-implant language skills ranged from extremely delayed to age appropriate. On average, skills…

  13. 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…

  14. Overt and covert verbal problem-solving strategies: developmental trends in use, awareness, and relations with task performance in children aged 5 to 17.

    PubMed

    Winsler, Adam; Naglieri, Jack

    2003-01-01

    Age-related changes in children's use, self report, and awareness of verbal problem-solving strategies (private speech) and strategy effectiveness were explored with a large (N = 2,156) cross-sectional sample of children aged 5 to 17. Children's verbal strategies moved from overt, to partially covert, to fully covert forms with age. Self-reports of verbal strategy use were accurate yet incomplete. Awareness of children's use of verbal strategies was low and increased with age. Although verbal strategies were associated with competence among the youngest children, self-talk was unrelated to task performance for older children, suggesting considerable persistence over time of a relatively ineffective strategy. Awareness was not a prerequisite for children's verbal strategy use but was positively associated with strategy effectiveness among those who talked.

  15. Analysis of advanced glycation endproducts in selected food items by ultra-performance liquid chromatography tandem mass spectrometry: Presentation of a dietary AGE database.

    PubMed

    Scheijen, Jean L J M; Clevers, Egbert; Engelen, Lian; Dagnelie, Pieter C; Brouns, Fred; Stehouwer, Coen D A; Schalkwijk, Casper G

    2016-01-01

    The aim of this study was to validate an ultra-performance liquid chromatography tandem mass-spectrometry (UPLC-MS/MS) method for the determination of advanced glycation endproducts (AGEs) in food items and to analyze AGEs in a selection of food items commonly consumed in a Western diet. N(ε)-(carboxymethyl)lysine (CML), N(ε)-(1-carboxyethyl)lysine (CEL) and N(δ)-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1) were quantified in the protein fractions of 190 food items using UPLC-MS/MS. Intra- and inter-day accuracy and precision were 2-29%. The calibration curves showed perfect linearity in water and food matrices. We found the highest AGE levels in high-heat processed nut or grain products, and canned meats. Fruits, vegetables, butter and coffee had the lowest AGE content. The described method proved to be suitable for the quantification of three major AGEs in food items. The presented dietary AGE database opens the possibility to further quantify actual dietary exposure to AGEs and to explore its physiological impact on human health. PMID:26213088

  16. Analysis of advanced glycation endproducts in selected food items by ultra-performance liquid chromatography tandem mass spectrometry: Presentation of a dietary AGE database.

    PubMed

    Scheijen, Jean L J M; Clevers, Egbert; Engelen, Lian; Dagnelie, Pieter C; Brouns, Fred; Stehouwer, Coen D A; Schalkwijk, Casper G

    2016-01-01

    The aim of this study was to validate an ultra-performance liquid chromatography tandem mass-spectrometry (UPLC-MS/MS) method for the determination of advanced glycation endproducts (AGEs) in food items and to analyze AGEs in a selection of food items commonly consumed in a Western diet. N(ε)-(carboxymethyl)lysine (CML), N(ε)-(1-carboxyethyl)lysine (CEL) and N(δ)-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1) were quantified in the protein fractions of 190 food items using UPLC-MS/MS. Intra- and inter-day accuracy and precision were 2-29%. The calibration curves showed perfect linearity in water and food matrices. We found the highest AGE levels in high-heat processed nut or grain products, and canned meats. Fruits, vegetables, butter and coffee had the lowest AGE content. The described method proved to be suitable for the quantification of three major AGEs in food items. The presented dietary AGE database opens the possibility to further quantify actual dietary exposure to AGEs and to explore its physiological impact on human health.

  17. Association between shift work history and performance on the trail making test in middle-aged and elderly humans: the EpiHealth study.

    PubMed

    Titova, Olga E; Lindberg, Eva; Elmståhl, Sölve; Lind, Lars; Schiöth, Helgi B; Benedict, Christian

    2016-09-01

    Shift work has been proposed to promote cognitive disturbances in humans; however, conflicting evidence is also present. By using data from 7143 middle-aged and elderly humans (45-75 years) who participated in the Swedish EpiHealth cohort study, the present analysis sought to investigate whether self-reported shift work history would be associated with performance on the trail making test (TMT). The TMT has been proposed to be a useful neuropsychological tool to evaluate humans' executive cognitive function, which is known to decrease with age. After adjustment for potential confounders (e.g., age, education, and sleep duration), it was observed that current and recent former shift workers (worked shifts during the past 5 years) performed worse on the TMT than nonshift workers. In contrast, performance on the TMT did not differ between past shift workers (off from shift work for more than 5 years) and nonshift workers. Collectively, our results indicate that shift work history is linked to poorer performance on the TMT in a cohort of middle-aged and elderly humans. PMID:27459922

  18. 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…

  19. 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. PMID:25650512

  20. 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

  1. 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

  2. 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

    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

  3. 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

  4. 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…

  5. 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…

  6. Performance of San Joaquin Delta College Freshmen Students in Reading, Writing and Math by Ethnicity, High School Status and Age.

    ERIC Educational Resources Information Center

    Lewis, Merrilee R.; And Others

    A study was conducted in fall 1985 to determine how well students at San Joaquin Delta College (SJDC) were prepared in reading, writing, and mathematics, comparing students by ethnicity, high school status, and age. SJDC uses the Comparative Guidance Placement (CGP) Tests to to assess all new students who do not have an Associate of Arts degree or…

  7. 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.

  8. 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.

  9. 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…

  10. 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 ...

  11. 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. PMID:26500272

  12. 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.

  13. 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.

  14. 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

  15. 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…

  16. 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

  17. 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

    2014-07-01

    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

  18. 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.

  19. Age-associated declines in muscle mass, strength, power, and physical performance: impact on fear of falling and quality of life

    PubMed Central

    Trombetti, A.; Reid, K. F.; Hars, M.; Herrmann, F. R.; Pasha, E.; Phillips, E. M.; Fielding, R. A.

    2016-01-01

    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 life. Our findings reinforce the importance of preserving muscle health with advancing age. Introduction The age-associated loss of skeletal muscle quantity and function are critical determinants of independent physical functioning in later life. Longitudinal studies investigating how decrements in muscle components of sarcopenia impact fear of falling (FoF) and quality of life (QoL) in older adults are lacking. Methods Twenty-six healthy older subjects (age, 74.1±3.7; Short Physical Performance Battery (SPPB) score ≥10) and 22 mobility-limited older subjects (age, 77.2±4.4; SPPB score ≥9) underwent evaluations of lower extremity muscle size and composition by computed tomography, strength and power, and physical performance at baseline and after 3-year follow-up. The Falls Efficacy Scale (FES) and Short Form-36 questionnaire (SF-36) were also administered at both timepoints to assess FoF and QoL, respectively. Results At 3-year follow-up, muscle cross-sectional area (CSA) (p<0.013) and power decreased (p<0.001), while intermuscular fat infiltration increased (p<0.001). These decrements were accompanied with a longer time to complete 400 m by 22±46 s (p<0.002). Using linear mixed-effects regression models, declines of muscle CSA, strength and power, and SPPB score were associated with increased FES score (p<0.05 for each model). Reduced physical component summary score of SF-36 over follow-up was independently associated with decreased SPPB score (p<0.020), muscle CSA (p<0.046), and increased 400 m walk time (p<0.003). Conclusions In older adults with and without mobility limitations, declining muscle mass, strength, power, and physical performance contribute

  20. Effects of domain knowledge, working memory capacity, and age on cognitive performance: an investigation of the knowledge-is-power hypothesis.

    PubMed

    Hambrick, David Z; Engle, Randall W

    2002-06-01

    Domain knowledge facilitates performance in many cognitive tasks. However, very little is known about the interplay between domain knowledge and factors that are believed to reflect general, and relatively stable, characteristics of the individual. The primary goal of this study was to investigate the interplay between domain knowledge and one such factor: working memory capacity. Adults from wide ranges of working memory capacity, age, and knowledge about the game of baseball listened to, and then answered questions about, simulated radio broadcasts of baseball games. There was a strong facilitative effect of preexisting knowledge of baseball on memory performance, particularly for information judged to be directly relevant to the baseball games. However, there was a positive effect of working memory capacity on memory performance as well, and there was no indication that domain knowledge attenuated this effect. That is, working memory capacity contributed to memory performance even at high levels of domain knowledge. Similarly, there was no evidence that domain knowledge attenuated age-related differences (favoring young adults) in memory performance. We discuss implications of the results for understanding proficiency in cognitive domains from an individual-differences perspective.

  1. 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.

  2. 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.

  3. 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.

  4. Beef cow prepartum supplement level and age at weaning: II. Effects of developmental programming on performance and carcass composition of steer progeny.

    PubMed

    Shoup, L M; 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 dam supplement level and age at weaning on growth performance, glucose and insulin concentrations, and carcass characteristics of steers (134 steers in yr 1; 147 steers in yr 2). Mature, multiparous Angus × Simmental cows were used in a split-plot design that included 3 supplement levels (no supplement [NS], 2.16 kg·cow·d [LS], and 8.61 kg·cow·d [HS]) 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 distiller's grains plus solubles and 30% soybean hulls) 103 ± 11 d prepartum to 2 ± 11 d postpartum. Dam prepartum supplement level did not affect ( ≥ 0.29) finishing phase growth performance or morbidity. The percentage of steers grading Average Choice or greater was increased ( = 0.04) for steers from cows fed HS compared to the percentage of steers from cows fed NS. Early weaning increased ( < 0.01) finishing phase initial BW and final BW and reduced ( < 0.01) G:F compared to normal weaning. A year × wean interaction ( = 0.04) occurred for ADG; EW resulted in reduced ( < 0.01) ADG compared to NW in yr 2. At slaughter, EW steers had greater ( < 0.01) HCW, yield grade, and back fat than NW steers. A year × wean interaction ( ≤ 0.05) occurred for quality grade distribution; in yr 2, EW steers had a greater ( < 0.01) proportion of carcasses that graded Low Choice or greater and Average Choice or greater than carcasses from NW steers. The EW steers had greater ( ≤ 0.05) occurrence of single antibiotic treatments in yr 2 and mortality due to respiratory disease than NW steers. A trend for a year × wean interaction ( ≤ 0.07) occurred for plasma insulin concentration and insulin:glucose; EW steers had numerically greater plasma insulin concentrations and insulin:glucose than NW steers in yr 1. In conclusion, these data suggest that there is no

  5. Training to improve manual control in 7-8 and 10-12 year old children: Training eliminates performance differences between ages.

    PubMed

    Snapp-Childs, Winona; Fath, Aaron J; Watson, Carol A; Flatters, Ian; Mon-Williams, Mark; Bingham, Geoffrey P

    2015-10-01

    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.

  6. 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

  7. 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

  8. 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. PMID:26954217

  9. 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.

  10. The level of association between functional performance status measures and patient-reported outcomes in cancer patients: a systematic review

    PubMed Central

    Andreotti, Charissa F.; Roberts, Kailey E.; Saracino, Rebecca M.; Hernandez, Marisol; Basch, Ethan

    2016-01-01

    Purpose The process of assessing patient symptoms and functionality using patient-reported outcomes (PROs) and functional performance status (FPS) is an essential aspect of patient-centered oncology research and care. However, PRO and FPS measures are often employed separately or inconsistently combined. Thus, the purpose of this study was to conduct a systematic review of the level of association between PRO and FPS measures to determine their differential or combined utility. Methods A systematic search was conducted using five databases (1966 to February 2014) to identify studies that described an association between PRO and FPS. Studies were excluded if they were non-cancer specific, did not include adults aged 18 or older, or were review articles. Publications were selected for review by consensus among two authors, with a third author arbitrating as needed. Results A total of 18 studies met inclusion criteria. FPS was primarily assessed by clinicians using the ECOG Performance Status or Karnofsky Performance Status measures. PROs were captured using a variety of measures, with numerous domains assessed (e.g., pain, fatigue, and general health status). Concordance between PROs and FPS measures was widely variable, falling in the low to moderate range (0.09–0.72). Conclusions Despite consistency in the method of capture of PROs or FPS, domain capture varied considerably across reviewed studies. Irrespective of the method of capturing PROs or FPS, the quantified level of association between these two areas was moderate at best, providing evidence that FPS and PRO assessments offer unique information to assist clinicians in their decision-making. PMID:26314706

  11. Effect of milk replacer program on calf performance and digestion of nutrients in dairy calves to 4 months of age.

    PubMed

    Hill, T M; Quigley, J D; Bateman, H G; Suarez-Mena, F X; Dennis, T S; Schlotterbeck, R L

    2016-10-01

    Calves fed >0.7kg of dry matter from milk replacer (MR) typically have greater growth preweaning but lower growth postweaning. This is partially explained by lower digestibility of starter due to less development of the rumen at and after weaning; however, it is unclear when digestibility matures postweaning to levels typical of mature ruminants. Thus, we fed Holstein calves (initially 2 to 3d of age) 3 MR programs (MOD=0.66kg daily for 39d, and then 0.33kg daily for 3d, n=15 calves; HIMOD=0.88kg daily for 5d, then 1.1kg daily for 23d, then 0.66kg daily for 18d, and then 0.33kg daily for 3d, n=16 calves; HI=0.88kg daily for 5d, then 1.1kg daily for 37d, and then 0.56kg daily for 7d, n=15 calves). The MR consisted of 28% crude protein and 20% fat and was reconstituted to 14% solids and fed at 0630 and 1400 h daily. A 39% starch textured starter (19% crude protein) was fed free-choice for the first 56d of a nursery trial with calves in individual pens. From 56 to 112d, calves were grouped by MR program into pens of 3 to 4 calves and offered a starter with the same ingredient composition blended with 5% chopped grass hay for ad libitum consumption. Digestion was estimated at 11 and 16wk. Measurements in the first and second 56d were analyzed separately in a completely randomized design using repeated measurements when applicable. Preplanned contrasts of MOD versus HIMOD and MOD versus HI were used to separate means. Milk replacer dry matter intake was 26.6, 42.4, and 48.7kg in calves fed MOD, HIMOD, and HI, respectively. Starter intake was less for calves fed HIMOD and HI versus MOD from 3 to 8wk. Efficiency of metabolizable energy and protein used for body weight gain did not differ among programs. During the second 56d, body weight gain and hip width changes were greater for calves fed MOD than HI. Total 112-d body weight gain and total hip width changes were 101.4, 101.3, and 101.7kg, and 9.0, 9.1, and 8.7cm for MOD, HIMOD, and HI, respectively. Digestibility of

  12. Effects of age and soccer expertise on general tests of perceptual and motor performance among adolescent soccer players.

    PubMed

    Vänttinen, T; Blomqvist, M; Luhtanen, P; Häkkinen, K

    2010-06-01

    This study of perceptual and motor skills in soccer players was conducted on adolescent males. The goals were to monitor the development of general perceptual motor skills in nonsoccer-playing and soccer-playing groups (n = 245), to examine the relationship between physical maturity and general perceptual motor skills (n = 41), and to compare the differences in general perceptual motor skills between groups with different soccer expertise (n = 142). The measured variables were simple reaction time, peripheral awareness, eye-hand-foot coordination, and testosterone blood level. The results suggested that general perceptual motor skills improved with age, the development of these skills was related to participants' blood testosterone concentration (especially between 12 and 14 years), and general perceptual motor skills improved with soccer expertise. However, the differences between subelite and elite soccer players were not meaningful enough to encourage practitioners to test general perceptual motor skills on a large scale when evaluating the potential of young players.

  13. Effect of milk replacer program on calf performance and digestion of nutrients in dairy calves to 4 months of age.

    PubMed

    Hill, T M; Quigley, J D; Bateman, H G; Suarez-Mena, F X; Dennis, T S; Schlotterbeck, R L

    2016-10-01

    Calves fed >0.7kg of dry matter from milk replacer (MR) typically have greater growth preweaning but lower growth postweaning. This is partially explained by lower digestibility of starter due to less development of the rumen at and after weaning; however, it is unclear when digestibility matures postweaning to levels typical of mature ruminants. Thus, we fed Holstein calves (initially 2 to 3d of age) 3 MR programs (MOD=0.66kg daily for 39d, and then 0.33kg daily for 3d, n=15 calves; HIMOD=0.88kg daily for 5d, then 1.1kg daily for 23d, then 0.66kg daily for 18d, and then 0.33kg daily for 3d, n=16 calves; HI=0.88kg daily for 5d, then 1.1kg daily for 37d, and then 0.56kg daily for 7d, n=15 calves). The MR consisted of 28% crude protein and 20% fat and was reconstituted to 14% solids and fed at 0630 and 1400 h daily. A 39% starch textured starter (19% crude protein) was fed free-choice for the first 56d of a nursery trial with calves in individual pens. From 56 to 112d, calves were grouped by MR program into pens of 3 to 4 calves and offered a starter with the same ingredient composition blended with 5% chopped grass hay for ad libitum consumption. Digestion was estimated at 11 and 16wk. Measurements in the first and second 56d were analyzed separately in a completely randomized design using repeated measurements when applicable. Preplanned contrasts of MOD versus HIMOD and MOD versus HI were used to separate means. Milk replacer dry matter intake was 26.6, 42.4, and 48.7kg in calves fed MOD, HIMOD, and HI, respectively. Starter intake was less for calves fed HIMOD and HI versus MOD from 3 to 8wk. Efficiency of metabolizable energy and protein used for body weight gain did not differ among programs. During the second 56d, body weight gain and hip width changes were greater for calves fed MOD than HI. Total 112-d body weight gain and total hip width changes were 101.4, 101.3, and 101.7kg, and 9.0, 9.1, and 8.7cm for MOD, HIMOD, and HI, respectively. Digestibility of

  14. 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 ...

  15. 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…

  16. 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. PMID:24611246

  17. 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.

  18. 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. PMID:26334906

  19. 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. PMID:25485195

  20. 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.

  1. 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.

  2. 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

  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. PMID:25057193

  4. 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.

  5. Peak procedure performance in young adult and aged rats: acquisition and adaptation to a changing temporal criterion.

    PubMed

    Lejeune, H; Ferrara, A; Soffíe, M; Bronchart, M; Wearden, J H

    1998-08-01

    Twenty-four-month-old and 4-month-old rats were trained on a peak-interval procedure, where the time of reinforcement was varied twice between 20 and 40 sec. Peak times from the old rats were consistently longer than the reinforcement time, whereas those from younger animals tracked the 20- and 40-sec durations more closely. Different measures of performance suggested that the old rats were either (1) systematically misremembering the time of reinforcement or (2) using an internal clock with a substantially greater latency to start and stop timing than the younger animals. Old rats also adjusted more slowly to the first transition from 20 to 40 sec than did the younger ones, but not to later transitions. Correlations between measures derived from within-trial patterns of responding conformed in general to detailed predictions derived from scalar expectancy theory. However, some correlation values more closely resembled those derived from a study of peak-interval performance in humans and a theoretical model developed by Cheng and Westwood (1993), than those obtained in previous work with animals, for reasons that are at present unclear.

  6. 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.

  7. Associations of Insulin and Insulin-Like Growth Factors with Physical Performance in Old Age in the Boyd Orr and Caerphilly Studies

    PubMed Central

    Birnie, Kate; Ben-Shlomo, Yoav; Holly, Jeff M. P.; Gunnell, David; Ebrahim, Shah; Bayer, Antony; Gallacher, John; Martin, Richard M.

    2012-01-01

    Objective Insulin and the insulin-like growth factor (IGF) system regulate growth and are involved in determining muscle mass, strength and body composition. We hypothesised that IGF-I and IGF-II are associated with improved, and insulin with worse, physical performance in old age. Methods Physical performance was measured using the get-up and go timed walk and flamingo balance test at 63–86 years. We examined prospective associations of insulin, IGF-I, IGF-II and IGFBP-3 with physical performance in the UK-based Caerphilly Prospective Study (CaPS; n = 739 men); and cross-sectional insulin, IGF-I, IGF-II, IGFBP-2 and IGFBP-3 in the Boyd Orr cohort (n = 182 men, 223 women). Results In confounder-adjusted models, there was some evidence in CaPS that a standard deviation (SD) increase in IGF-I was associated with 1.5% faster get-up and go test times (95% CI: −0.2%, 3.2%; p = 0.08), but little association with poor balance, 19 years later. Coefficients in Boyd Orr were in the same direction as CaPS, but consistent with chance. Higher levels of insulin were weakly associated with worse physical performance (CaPS and Boyd Orr combined: get-up and go time = 1.3% slower per SD log-transformed insulin; 95% CI: 0.0%, 2.7%; p = 0.07; OR poor balance 1.13; 95% CI; 0.98, 1.29; p = 0.08), although associations were attenuated after controlling for body mass index (BMI) and co-morbidities. In Boyd Orr, a one SD increase in IGFBP-2 was associated with 2.6% slower get-up and go times (95% CI: 0.4%, 4.8% slower; p = 0.02), but this was only seen when controlling for BMI and co-morbidities. There was no consistent evidence of associations of IGF-II, or IGFBP-3 with physical performance. Conclusions There was some evidence that high IGF-I and low insulin levels in middle-age were associated with improved physical performance in old age, but estimates were imprecise. Larger cohorts are required to confirm or refute the findings. PMID:22253890

  8. 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

  9. 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

  10. 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.

  11. 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

  12. 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%). PMID:26623373

  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. 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. PMID:25602026

  15. 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.

  16. The cutoffs and performance of glycated hemoglobin for diagnosing diabetes and prediabetes in a young and middle-aged population and in an elderly population.

    PubMed

    Yan, Shuang-Tong; Xiao, Hai-Ying; Tian, Hui; Li, Chun-Lin; Fang, Fu-Sheng; Li, Xiao-Ying; Cheng, Xiao-Ling; Li, Nan; Miao, Xin-Yu; Yang, Yan; Wang, Liang-Chen; Zou, Xiao-Man; Ma, Fang-Ling; He, Yao; Sai, Xiao-Yong

    2015-08-01

    The aims were to compare the appropriate cutoffs of glycated hemoglobin (HbA1c) in a population of varying ages and to evaluate the performance of HbA1c for diagnosing diabetes and prediabetes. A total of 1064 participants in the young and middle-aged group and 1671 in the elderly group were included and underwent HbA1c testing and an oral glucose tolerance test (OGTT). Sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were calculated to evaluate the optimal HbA1c cutoffs. Kappa coefficients were used to test for agreement between HbA1c categorization and OGTT-based diagnoses. The optimal HbA1c cutoffs for diagnosing diabetes were 5.7% (39 mmol/mol) in the young and middle-aged group with a sensitivity of 66.7%, specificity of 86.7%, and AUC of 0.821 (95% CI: 0.686, 0.955) and 5.9% (41 mmol/mol) in the elderly group with a sensitivity of 80.4%, specificity of 73.3%, and AUC of 0.831 (0.801, 0.861). The optimal cutoffs for diagnosing prediabetes were 5.6% (38 mmol/mol) and 5.7% (39 mmol/mol) in the young and middle-aged group and in the elderly group, respectively. Agreement between the OGTT-based diagnosis of diabetes or prediabetes and the optimal HbA1c cutoff was low (all kappa coefficients <0.4). The combination of HbA1c and fasting plasma glucose increased diagnostic sensitivities or specificities. In conclusion, age-specific HbA1c cutoffs for diagnosing diabetes or prediabetes were appropriate. Furthermore, the performance of HbA1c for diagnosing diabetes and prediabetes was poor. HbA1c should be used in combination with traditional glucose criteria when detecting and diagnosing diabetes or prediabetes.

  17. High alcohol consumption in middle aged adults is associated with poorer cognitive performance only in the low socioeconomic group. Results from the GAZEL cohort study

    PubMed Central

    Sabia, Séverine; Guéguen, Alice; Berr, Claudine; Berkman, Lisa; Ankri, Joël; Goldberg, Marcel; Zins, Marie; Singh-Manoux, Archana

    2010-01-01

    Aims To examine the association of alcohol consumption over 10 years with cognitive performance in different socioeconomic groups. Design Prospective cohort study, the French GAZEL study. Setting France. Participants Employees of France’s national electricity and gas company. Measurements Alcohol intake was assessed annually, beginning in 1992, using questions on frequency and quantity of alcoholic beverages consumed in a week; used to define mean consumption and trajectory of alcohol intake over 10 years. Cognitive performance among participants aged ≥55 years (N=4073) was assessed in 2002–2004 using the Digit Symbol Substitution Test (DSST), a measure of psychomotor speed, attention and reasoning. Occupational position at age 35 and education were used as the markers of socioeconomic position. Findings All analyses were stratified by socioeconomic position. In the low occupational group, participants consuming a mean of more than 21 drinks per week had 2.1 points lower (95% CI: −3.9, −0.3) DSST score compared to those consuming 4–14 drinks per week. In participants with primary school education, the corresponding difference was 3.6 points (95% CI: −7.1,−0.0). No association between alcohol consumption and cognitive performance was observed in the intermediate and high socioeconomic groups, defined using either occupation or education. Analysis of trajectories of alcohol consumption showed that in the low socioeconomic groups large increase or decrease in alcohol consumption was associated with lower cognitive scores compared to stable consumption. Conclusions Our results suggest that high alcohol consumption is associated with poorer cognitive performance only in the low socioeconomic group, possibly due to greater cognitive reserve in the higher socioeconomic groups. PMID:20840170

  18. Aging and Urbanization: The Neighborhood Perception and Functional Performance of Elderly Persons in Belo Horizonte Metropolitan Area-Brazil.

    PubMed

    Ferreira, Fabiane Ribeiro; César, Cibele Comini; Camargos, Vitor Passos; Lima-Costa, Maria Fernanda; Proietti, Fernando Augusto

    2010-01-01

    Currently, half of the world population resides in cities. The percentage of world population that is elderly is expected to double from 11% to 22% by 2050 and will be concentrated in urban areas of developing countries. The purpose of this study was to evaluate the functional status of elderly who live in the Belo Horizonte Metropolitan Area, Minas Gerais State, Brazil. The International Classification of Functioning, Disability and Health (ICF) was employed as the theoretical model. Probabilistic sampling was used to select 1,611 elderly persons (defined as >/=60 years) for the study. The response variable "functional performance" was developed by counting the number of basic and instrumental activities of daily living (ADL) that subjects found difficult to carry out. A zero-inflated negative binomial (ZINB) regression model was fitted to the data. The prevalence of disability was 47.1%. Neighborhood self-perception revealed that 84.0% of the elderly were satisfied with their neighborhood, although only 18.4% trusted people around them. Concerns about walking around the neighborhood were: fear of being robbed (78.0%) and fear of falling due to sidewalk defects (48.2%), which caused a 62% increase in the number of ADL carried out with difficulty. It is well known that there is a continuous tendency for functional results to improve as the frequency of walking increases. Thus, urban infrastructure interventions, such as improving public sidewalks, might influence the frequency of elderlies walking in their neighborhoods. Making walking possible-or even pleasant-could increase their social participation and use of services. PMID:19924540

  19. The effects of age and production mode on the bilingual performance of Turkish learners of English in a serial recall task.

    PubMed

    Akca, Catherine; Elkilic, Gencer

    2011-02-01

    The cognitive resources available to the working memory system are finite. Under conditions of cognitive overload, a compromise may need to be made between the demands of storage and processing. Research suggests that the cognitive cost of partially automated transcription processes adversely affects written language production in children. Thus, children may be expected to perform the same task better orally than in writing. In order to determine whether this is the case in a Turkish context, three samples of participants, comprising 16 undergraduate students, 16 fifth-grade and 16 third-grade pupils, were required to perform oral and written serial recall of Turkish word lists. Recall mode did not interact significantly with age. In the adult sample, the combined samples of schoolchildren, and the fifth-grade sample of children written recall was significantly better than oral recall. This may reflect the transparency of Turkish orthography and/or the age of the participating children. However, when the test was administered in English, no effect of modality was observed in children. This suggests that when the additional cognitive costs of processing a less automated language are combined with transcription costs, the resources available to children in working memory for the storage of information are depleted. PMID:22044128

  20. The Associations Between Executive Functions' Capacities, Performance Process Skills, and Dimensions of Participation in Activities of Daily Life Among Children of Elementary School Age.

    PubMed

    Rosenberg, Limor

    2015-01-01

    Effective executive functions (EFs) are crucial for efficient daily functioning. Daily functioning or involvement in life situations is defined as "participation" (International Classification of Functioning, Disability, and Health [ICF]; World Health Organization, 2001). Yet associations between them have been inadequately studied for children. The present study aimed to explore the associations between EFs and child participation. Participants were 60 typically developing children aged 6 to 9 years old and their parents. The children were individually evaluated using five EF cognitive tests. The parents completed three questionnaires: the Children Participation Questionnaire, the Process Skills (the observed executive performance) Questionnaire, and the Environmental Restrictions Questionnaire. Most of the EF scores were associated with the child's age. A unique contribution of executive capacities was found for the "independence" aspect of child participation, though the quantum of contribution was limited compared with the other predictors' process skills and environmental restrictions. In the context of child participation, EFs should be studied through multivariate analysis, as otherwise, the unique contribution of executive capacities measured by neuropsychological cognitive tests are likely to be ignored. Process skills are crucial for a child's independence and autonomy in daily functioning. These findings are supported by the capacity-performance distinction suggested by the ICF model. PMID:25072941

  1. Effects of dietary energy on growth performance and carcass quality of white growing pekin ducks from two to six weeks of age.

    PubMed

    Fan, H P; Xie, M; Wang, W W; Hou, S S; Huang, W

    2008-06-01

    A dose-response experiment with 6 dietary energy levels (2,600, 2,700, 2,800, 2,900, 3,000, 3,100 kcal of AME /kg) was conducted to study the effects of dietary energy on growth performance and carcass quality of White Pekin ducks from 2 to 6 wk of age. Six hundred 14-d-old White Pekin ducks were randomly divided to 6 dietary treatments, each containing 5 replicate pens with 10 males and 10 females per pen, and these birds were raised until 6 wk of age. At 42 d of age, weight gain, feed intake, and feed:gain of ducks from each pen were measured, and 2 ducks (1 male and 1 female) selected randomly from each pen were slaughtered to evaluate the yields of abdominal fat, breast meat (including pectoralis major and pectoralis minor), and leg meat (including thigh and drumstick). As dietary energy increased from 2,600 to 3,100 kcal of AME/kg, the weight gain of ducks increased significantly, and the feed intake and feed:gain decreased significantly. According to the broken-line regression analysis, the AME requirements of White Pekin ducks from 2 to 6 wk of age for optimal weight gain and feed:gain were 3,008 and 3,030 kcal/kg, respectively, when dietary protein was 18%. On the other hand, high dietary energy did not affect breast and leg meat (P > 0.05), but abdominal fat increased (P < 0.05) when dietary AME was above 2,700 kcal/kg.

  2. 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

  3. 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

  4. 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

  5. Socioeconomic status, child enrichment factors, and cognitive performance among preschool-age children: Results from the Follow-Up of Growth and Development Experiences study☆

    PubMed Central

    Christensen, Deborah L.; Schieve, Laura A.; Devine, Owen; Drews-Botsch, Carolyn

    2015-01-01

    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

  6. 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.

  7. A comparison of the effects of feeding treatments and lighting on age at first egg and subsequent laying performance and carcase composition of broiler breeder hens.

    PubMed

    Ciacciariello, M; Gous, R M

    2005-04-01

    The effects of the growth curve from 15 to 20 weeks, age at photostimulation and pattern of photostimulus on sexual maturity, egg production and egg weight were evaluated in two trials with broiler breeder females to 56 and 34 weeks of age (housed in litter pens and individually caged, respectively). Carcase composition and reproductive morphology of hens varying in laying efficiency were measured in the second trial. Trial 1: Four growth curves were applied from 15 to 20 weeks to pullets housed in litter pens. Birds were transferred from 8- to 10-h photoperiods at 20 or 24 weeks of age, followed by weekly increments of one hour to reach a 16-h final photoperiod. Lower-than-recommended body weights at 20 weeks significantly delayed sexual maturity, reduced peak rate of lay, total eggs and mean egg weight. However, double-yolked egg production was lower, resulting in non-significant differences in settable egg numbers between body weight treatments. Birds reared to the heaviest body weight exhibited a significantly advanced sexual maturity, but total egg numbers, peak rate of lay and mean egg weight were not significantly affected. However, the laying of more double-yolked eggs resulted in a decrease in the number of settable eggs. Delaying photostimulation to 24 weeks significantly retarded sexual maturity, reduced total and settable egg numbers, and increased mean egg weight. A tendency for fewer double-yolked eggs was observed. Trial 2: At 19 weeks, birds were selected from the 4 body weight categories in Trial 1 and moved to individual cages in 8 rooms. Five lighting programmes were applied. The pattern of photostimulation applied did not affect any of the production traits measured. At 34 weeks, 24 birds were selected for the analysis of reproductive morphology, presence of internal or multiple ovulations, and carcase composition. Eight hens showing an early age at first egg and regular egg production records, 8 birds showing erratic laying performance and 8

  8. The relationship between weight, age, and average daily gain to show performance of Georgia 4-H and Future Farmers of America (FFA) commercial dairy heifers.

    PubMed

    London, M L; Bernard, J K; Froetschel, M A; Bertrand, J K; Graves, W M

    2012-02-01

    Three studies were conducted to determine the relationship between dairy heifer growth and placing in the show ring. In the first study, 1,744 commercial dairy heifers (all breeds and crossbred animals) were evaluated to determine effects of growth on placing within Georgia Commercial Dairy Heifer Shows from 2007 to 2010. Birth weights were determined using breed birth weight averages, with crossbreeds being the average of 2 parent breeds. Average daily gains (ADG) were calculated and heifers were given rankings based on placing in show and for age and weight. Data was analyzed using the Spearman correlation calculations in the SAS software (SAS Institute Inc., Cary, NC). Age and ADG were inversely correlated (r=-0.89). Mean ADG for all heifers was determined to be 0.65 kg, below National Research Council recommendations of 0.7 to 0.8 kg. No strong relationship (r=-0.07) was observed between ADG and placing. Heavier heifers within a class showed a small positive relationship (r=0.10) with placing. For study 2, 238 heifers shown at the 2010 Georgia Junior National Livestock Show (Perry, GA) were measured and evaluated for ADG, placing, body weight, age, withers height, hip height, hip width, and jaw width. Height at withers had a moderate relationship (r=0.42) with placing, followed by hip height (r=0.32). A positive relationship (r=0.65) was observed between withers height and hip height. The correlation between weight and placing was determined (r=0.11). Age and ADG had a strong inverse relationship (r=-0.87). Study 3 evaluated 1,489 Holstein heifers shown from 2007 to 2010. Data was analyzed using the Penn State Growth Monitor Spreadsheet Curves. In total, 63.75% did not meet Penn State recommendations for body weight gain. Performance and physical features associated with age indicates that commercial dairy heifers are underfed. The effects of heat stress and high feed costs also play a role. This has economic implications because these animals will likely

  9. Neuropsychological performance in cancer patients: the role of oral opioids, pain and performance status.

    PubMed

    Sjøgren, P; Olsen, A K; Thomsen, A B; Dalberg, J

    2000-06-01

    The aim of the present study was to evaluate the possible influence of oral opioids, pain and performance status on some aspects of psychomotor function and cognition in cancer patients. One hundred and thirty cancer patients between 40 and 76 years of age were consecutively included in the study. In order to separate the impact of performance status, pain and oral opioids on neuropsychological functioning the patients were allocated in a cross-sectional design to five different groups. Group 1 (N=40), which was considered the control group, was characterized by being in Karnofsky Performance Status (KPS) A ('Able to carry on normal activity and work. No special care is needed'), had no pain and received no oral opioid medication. Group 2 (N=19) was characterized by being in KPS B ('Unable to work. Able to live at home and care for most personal needs. A varying degree of assistance is needed'), had no pain and received no oral opioid medication. Group 3 (N=19) was characterized by being in KPS B, had pain, but received no oral opioid medication. Group 4a (N=31) was characterized by being in KPS B, had pain and received stable doses of oral opioids. Group 4b (N=21) was characterized by being in KPS B, had no pain and received stable doses of opioids. Assessments comprised pain intensity, sedation, opioid doses, time from ingestion of last opioid dose to testing and opioid side effects. The neuropsychological tests used were continuous reaction time (CRT), finger tapping test (FTT) and paced auditory serial addition task (PASAT). Regarding the neuropsychological tests group 1 was compared with each of the other groups and respecting the hierarchy of increasing numbers of stigmatizing factors group 1 was compared with group 2, group 2 with group 3 and so forth. Concerning CRT, group 1 performed statistically significantly faster than groups 2, 4a and 4b. Concerning FTT, group 1 performed statistically significantly faster than groups 3 and 4a. Concerning PASAT

  10. Effects of castration age, dietary protein level and lysine/methionine ratio on animal performance, carcass and meat quality of Friesian steers intensively reared.

    PubMed

    Prado, I N; Campo, M M; Muela, E; Valero, M V; Catalan, O; Olleta, J L; Sañudo, C

    2014-09-01

    The effects of castration age, dietary protein level and the dietary lysine/methionine (lys/met) ratio on animal performance, carcass characteristics and meat quality were studied in 64 intensively reared Friesian steers. Animals underwent castration procedures at 15 days old or at 5 months old. Dietary treatments started at 90 days old, with eight animals from each castration age randomly allocated to each treatment: 14.6% v. 16.8% CP (DM basis), and 3.0 v. 3.4 lys/met, on a 2×2×2 design. The recommended ratio of 3.0 was reached with supplementation of protected methionine. Steers were slaughtered at 443.5±26.2 kg live weight when they reached 12 months old approximately. Average daily gain, cold carcass weight or carcass classification were not affected by any studied effect. Muscle moisture (P=0.024), C18:2n-6 percentage (P=0.047), polyunsaturated fatty acid/saturated fatty acid (P=0.049) and n-6/n-3 (P=0.003) were higher in late castrated animals. Both high levels of dietary protein (P=0.008) and lys/met ratio (P=0.048) increased the percentage of muscle in the carcass. A level of 16.8% of CP in the diet also increased the percentage of monounsaturated fatty acids in the intramuscular fat (P=0.032), whereas a ratio lys/met of 3.4 decreased the percentage of saturated fatty acids (P=0.028). Thus, it is recommended using diets with a high protein level (16.8%) and a high lys/met ratio (3.4) in animals slaughtered at a young age, in order to obtain carcasses with high muscle content without negatively affecting productive traits or intramuscular fat composition.

  11. Aging effects on explosive performance

    SciTech Connect

    Souers, C; Wu, B

    1998-08-20

    Bigplate and the Cylinder Test have been pushed into baseline LX-l 7 measurements. The non-ideality of LX-11 and the need for a time-dependent Equation of State has been shown. The first calculations of Equilibrium CHEETAH (TTL-06) linked to the 2-D code HEMP were made. An unexpected time lag not predicted by the code was seen in Bigplate. Extensive metal spa11 was also seen.

  12. Effect of transportation duration of 1-day-old chicks on postplacement production performances and pododermatitis of broilers up to slaughter age.

    PubMed

    Bergoug, H; Guinebretière, M; Tong, Q; Roulston, N; Romanini, C E B; Exadaktylos, V; Berckmans, D; Garain, P; Demmers, T G M; McGonnell, I M; Bahr, C; Burel, C; Eterradossi, N; Michel, V

    2013-12-01

    This experiment studied the effect of transportation duration of 1-d-old chicks on dehydration, mortality, production performance, and pododermatitis during the growout period. Eggs from the same breeder flock (Ross PM3) were collected at 35, 45, and 56 wk of age, for 3 successive identical experiments. In each experiment, newly hatched chicks received 1 of 3 transportation duration treatments from the hatchery before placement in the on-site rearing facility: no transportation corresponding to direct placement in less than 5 min (T0