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Sample records for age karnofsky performance

  1. 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

  2. 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.

  3. Age and Scientific Performance.

    ERIC Educational Resources Information Center

    Cole, Stephen

    1979-01-01

    The long-standing belief that age is negatively associated with scientific productivity and creativity is shown to be based upon incorrect analysis of data. Studies reported in this article suggest that the relationship between age and scientific performance is influenced by the operation of the reward system. (Author)

  4. ‘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

  5. GEM: Performance and aging tests

    SciTech Connect

    Cho, H.S.; Kadyk, J.; Han, S.H.; Hong, W.S.; Perez-Mendez, V.; Wenzel, W.; Pitts, K.; Martin, M.D.; Hutchins, J.B.

    1999-06-01

    Performance and aging tests have been done to characterize Gas Electron Multipliers (GEMs), including further design improvements such as a thicker GEM and a closed GEM. Since the effective GEM gain is typically smaller than the absolute GEM gain, due to trapping of avalanche electrons at the bottom GEM electrode, the authors performed field simulations and measurements for better understanding, and discuss methods to eliminate this effect. Other performance parameters of the GEMs are also presented, including absolute GEM gain, short-term and long-term gain stabilities.

  6. 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

  7. Adult age trends in athletic performances.

    PubMed

    Stones, M J; Kozma, A

    1981-01-01

    Aged trends in male, world record, track and field performances were examined over the 40-69 years age range. Five hypotheses were compared with respect to accuracy of prediction of differential age trends across events. The only hypothesis to yield statistically significant predictions was termed that of energy expenditure-supply ratio. This hypothesis predicts performance changes with age to exhibit steeper overall declines for events for events associated with higher maximal force transmissions, relative to the available (anaerobic or aerobic) energy supply. PMID:7318855

  8. Aging, Cognitive Performance, and Mental Speed.

    ERIC Educational Resources Information Center

    Nettelbeck, Ted; Rabbitt, Patrick M. A.

    1992-01-01

    Measures of four-choice reaction time, inspection time, and scores on a speeded coding-substitution task obtained from 104 adults aged 54 to 85 years were found to account for almost all age-related changes in cognitive performance on a number of indices of general fluid ability. (SLD)

  9. The Effects of Aging on Motor Performance.

    ERIC Educational Resources Information Center

    Kleinman, Matthew

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

  10. Unimanual Performance across the Age Span

    ERIC Educational Resources Information Center

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

    2005-01-01

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

  11. 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

  12. 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…

  13. 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...

  14. Neuroimaging explanations of age-related differences in task performance

    PubMed Central

    Steffener, Jason; Barulli, Daniel; Habeck, Christian; Stern, Yaakov

    2014-01-01

    Advancing age affects both cognitive performance and functional brain activity and interpretation of these effects has led to a variety of conceptual research models without always explicitly linking the two effects. However, to best understand the multifaceted effects of advancing age, age differences in functional brain activity need to be explicitly tied to the cognitive task performance. This work hypothesized that age-related differences in task performance are partially explained by age-related differences in functional brain activity and formally tested these causal relationships. Functional MRI data was from groups of young and old adults engaged in an executive task-switching experiment. Analyses were voxel-wise testing of moderated-mediation and simple mediation statistical path models to determine whether age group, brain activity and their interaction explained task performance in regions demonstrating an effect of age group. Results identified brain regions whose age-related differences in functional brain activity significantly explained age-related differences in task performance. In all identified locations, significant moderated-mediation relationships resulted from increasing brain activity predicting worse (slower) task performance in older but not younger adults. Findings suggest that advancing age links task performance to the level of brain activity. The overall message of this work is that in order to understand the role of functional brain activity on cognitive performance, analysis methods should respect theoretical relationships. Namely, that age affects brain activity and brain activity is related to task performance. PMID:24672481

  15. 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)

  16. 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

  17. The relationship of age to ten dimensions of job performance.

    PubMed

    Ng, Thomas W H; Feldman, Daniel C

    2008-03-01

    Previous reviews of the literature on the relationship between age and job performance have largely focused on core task performance but have paid much less attention to other job behaviors that also contribute to productivity. The current study provides an expanded meta-analysis on the relationship between age and job performance that includes 10 dimensions of job performance: core task performance, creativity, performance in training programs, organizational citizenship behaviors, safety performance, general counterproductive work behaviors, workplace aggression, on-the-job substance use, tardiness, and absenteeism. Results show that although age was largely unrelated to core task performance, creativity, and performance in training programs, it demonstrated stronger relationships with the other 7 performance dimensions. Results also highlight that the relationships of age with core task performance and with counterproductive work behaviors are curvilinear in nature and that several sample characteristics and data collection characteristics moderate age-performance relationships. The article concludes with a discussion of key research design issues that may further knowledge about the age-performance relationship in the future. PMID:18361640

  18. 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…

  19. 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

  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. PMID:23525546

  1. 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. PMID:23356412

  2. 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

  3. 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

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

    PubMed

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

    2015-08-01

    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. Influence Of Implantation Age On School-Age Language Performance In Pediatric Cochlear Implant Users

    PubMed Central

    Tobey, Emily A.; Thal, Donna; Niparko, John K.; Eisenberg, Laurie S.; Quittner, Alexandra L.; Wang, Nae-Yuh

    2013-01-01

    Objective This study examined specific spoken language abilities of 160 children with severe-to-profound sensorineural hearing loss followed prospectively 4, 5, or 6 years after cochlear implantation. Study sample Ninety-eight children received implants before 2.5 years, and 62 children received implants between 2.5 and 5 years of age. Design Language was assessed using four subtests of the Comprehensive Assessment of Spoken Language (CASL). Standard scores were evaluated by contrasting age of implantation and follow-up test time. Results Children implanted under 2.5 years of age achieved higher standard scores than children with older ages of implantation for expressive vocabulary, expressive syntax, and pragmatic judgments. However, in both groups, some children performed more than two standard deviations below the standardization group mean, while some scored at or well above the mean. Conclusions Younger ages of implantation are associated with higher levels of performance, while later ages of implantation are associated with higher probabilities of continued language delays, particularly within subdomains of grammar and pragmatics. Longitudinal data from this cohort study demonstrate that after 6 years of implant experience, there is large variability in language outcomes associated with modifiers of rates of language learning that differ as children with implants age. PMID:23448124

  8. 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…

  9. 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

  10. 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.

  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. PMID:26881835

  12. 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.

  13. 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

  14. Effects of Reference Performance Testing During Aging Using Commercial Cells

    SciTech Connect

    Jon P. Christophersen; Chinh D. Ho; David Howell

    2005-07-01

    The Advanced Technology Development Program, under the oversight of the U.S. Department of Energy’s FreedomCAR and Vehicle Technologies Program, is investigating lithium-ion batteries for hybrid-electric vehicle applications. Cells are aged under various test conditions, including temperatures and states-of-charge. Life testing is interrupted at regular intervals to conduct reference performance tests (RPTs), which are used to measure changes in the electrical performance of the cells and then to determine cell degradation as a function of test time. Although designed to be unobtrusive, data from the Advanced Technology Development Gen 2 cells indicated that RPTs actually contributed to cell degradation and failure. A study was performed at the Idaho National Laboratory using commercially available lithium-ion cells to determine the impact of RPTs on life. A series of partial RPTs were performed at regular intervals during life testing and compared to a control group that was life tested without RPT interruption. It was determined that certain components of the RPT were detrimental, while others appeared to improve cell performance. Consequently, a new "mini" RPT was designed as an unobtrusive alternative. Initial testing with commercial cells indicates that the impact of the mini RPT is significantly less than the Gen 2 cell RPT.

  15. 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.

  16. 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

  17. 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.

  18. Sex Differences in Participation, Performance, and Age of Ultramarathon Runners.

    PubMed

    Senefeld, Jonathon; Smith, Carolyn; Hunter, Sandra K

    2016-07-01

    The sex difference in marathon running is increased with lower participation of women than men, but whether this occurs for ultramarathon running is not known. The study purpose was to determine whether the sex difference in performance widens among lower-placed runners and the association between the sex difference in running speed and participation rates. The top-10 ultramarathon running times, age at performance date, and the number of men and women finishers were analyzed from 20 races (45-160 km) in the US Track and Field Ultra Running Grand Prix. Men were faster than women for all events (18.7% ± 5.8%, P < .001). The sex difference in speed was the least for 100 km (14.9% ± 4.2%) and greatest for 45-50 km (19.3% ± 5.8%). The top-10 men were younger than the top-10 women (37.7 ± 3.2 and 39.0 ± 3.1 y, respectively, P < .001). The sex difference in speed increased with finishing place (1st place 15.6% ± 6.6% vs 10th 20.8% ± 5.6%, P < .001). Association analysis showed that the sex difference in speed was largest when there were fewer women than men finishers in a race; the strength of the association was greatest for the 80-km distance and least for the 160-km. Lower participation rates of women than men in the lower-distance ultramarathons and less depth among lower-placed women runners inflate the sex difference in ultramarathon performance. PMID:26561864

  19. Age-Related Decrements in Stroop Color Test Performance.

    ERIC Educational Resources Information Center

    Cohn, Nancy B.; And Others

    1984-01-01

    Administered a modified Stroop Color-Word Test to healthy males (N=80) aged 21-90 years as part of a study of neuropsychological functioning. Results showed differences on simple reading tasks; however, significant age effects were observed for the color naming and interference tasks. (LLL)

  20. 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.

  1. Age dependent levels of plasma homocysteine and cognitive performance.

    PubMed

    Agrawal, Aruna; Ilango, K; Singh, Praveen K; Karmakar, Dipankar; Singh, G P I; Kumari, Rinki; Dubey, G P

    2015-04-15

    Elevated plasma homocysteine (hcy) levels, also known as hyperhomocysteinemia (hhcy), have been associated with cognitive impairment and neurodegenerative disorders. Hhcy has been attributed to deficiency of B vitamins which can adversely affect the brain and result in memory loss and poor attention power. Monitoring hcy levels and the use of vitamin supplementation to treat hhcy may therefore prove advantageous for the prevention and management of cognitive impairment. With this in consideration, we measured plasma hcy, folate and vitamin B12 levels in 639 subjects from different age groups in two sub-regions of India. Cognitive function was also measured using attention span and immediate and delayed memory recall tests. Depression scores were obtained using the Beck Depression Inventory-II and functional impairment was assessed using the functional activities questionnaire (FAQ) score. As hhcy has also been linked to inflammation, plasma levels of high sensitivity C-reactive protein (hsCRP) and interleukin-6 (IL-6) were also measured. The results demonstrated significant negative correlations between hcy levels and folic acid levels, vitamin B12 levels and cognitive performance (attention span and delayed but not immediate memory recall) along with significant positive correlations between hcy levels and depression scores and hsCRP (but not IL-6) levels. A positive correlation was also observed between hcy levels and FAQ scores, however this was not found to be significant. Based on these results, folic acid and vitamin B12 intervention in people with elevated hcy levels in India could prove to be effective in lowering hcy levels and help maintain or improve cognitive function. PMID:25601573

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

    ERIC Educational Resources Information Center

    Pearman, Ann; Trujillo, Amanda

    2013-01-01

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

  3. Motor Performance Age and Race Differences between Black and Caucasian Boys Six to Nine Years of Age.

    ERIC Educational Resources Information Center

    DiNucci, James M.

    This study was undertaken to compare the motor performance age and race differences between black and caucasian boys ages six to nine. One hundred and twenty subjects were administered 25 test items which measured (a) muscular strength, (b) muscular endurance, (c) cardio-respiratory endurance, (d) speed, (e) power, (f) agility, (g) balance, and…

  4. 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…

  5. 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.

  6. Evaluating Motor Performance of Preschool-Aged Children.

    ERIC Educational Resources Information Center

    Hirst, Cyntha C.; And Others

    The purpose of this project was to develop a motor performance test for preschool children that would be economical to administer, valid, and reliable. Four test items--standing long jump, hopping within an 18-inch square, balancing on one foot, and a timed gross agility task, were selected from published tests to assess children's strength,…

  7. Mobility in Old Age: Capacity Is Not Performance.

    PubMed

    Giannouli, Eleftheria; Bock, Otmar; 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

  8. 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

  9. 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…

  10. The impact of brewing yeast cell age on fermentation performance, attenuation and flocculation.

    PubMed

    Powell, Chris D; Quain, David E; Smart, Katherine A

    2003-04-01

    Individual cells of the yeast Saccharomyces cerevisiae exhibit a finite replicative lifespan, which is widely believed to be a function of the number of divisions undertaken. As a consequence of ageing, yeast cells undergo constant modifications in terms of physiology, morphology and gene expression. Such characteristics play an important role in the performance of yeast during alcoholic beverage production, influencing sugar uptake, alcohol and flavour production and also the flocculation properties of the yeast strain. However, although yeast fermentation performance is strongly influenced by the condition of the yeast culture employed, until recently cell age has not been considered to be important to the process. In order to ascertain the effect of replicative cell age on fermentation performance, age synchronised populations of a lager strain were prepared using sedimentation through sucrose gradients. Each age fraction was analysed for the ability to utilise fermentable sugars and the capacity to flocculate. In addition cell wall properties associated with flocculation were determined for cells within each age fraction. Aged cells were observed to ferment more efficiently and at a higher rate than mixed aged or virgin cell cultures. Additionally, the flocculation potential and cell surface hydrophobicity of cells was observed to increase in conjunction with cell age. The mechanism of ageing and senescence in brewing yeast is a complex process, however here we demonstrate the impact of yeast cell ageing on fermentation performance. PMID:12702447

  11. Age and Self-Selected Performance Pace on a Visual Monitoring Inspection Task.

    ERIC Educational Resources Information Center

    Panek, Paul E.; And Others

    1979-01-01

    Describes various performance measures used in a study to investigate the relation of performance pace to age and information processing ability. Test results indicated no differences in performance pace but differences in performance quality between young and older individuals, with implications for hiring and training older workers. (MF)

  12. 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

  13. Maximal lactate values following competitive performance varying according to age, sex and swimming style.

    PubMed

    Avlonitou, E

    1996-03-01

    Peak blood lactate concentration for a given individual in a given event could be considered as indicator of exercise effort, especially if the race is fast as it occurs following competitive swimming events. The present study attempts to describe the postcompetition lactate profile across all the swimming distances and strokes according to the age and sex of the swimmer. Blood samples (100 micro lambda) were taken from an arterialized fingertip of a total of 337 swimmers (171 males and 166 females) at the end of 3rd and 6th minutes of competition over 50 to 1500 meter distances and for the following 3 age group divisions: AGE1 = > 18 years of age, AGE2 = 16-17 years of age and AGE3 = 14-15 years of age. For AGE1 group the subjects who were picked up for testing were all the first three who met the criteria for this age category in the OPEN winter and summer National and Provincial Championships. For AGE2 and AGE3 groups the subjects who were picked up for testing were ranked among the first three in their age group winter and summer National and Provincial Championships. Results showed that the highest mean peak lactate values for groups AGE2 and AGE3 were recorded in 200 medley event for both sexes while for group AGE1 the highest mean peak lactate value was recorded in 200 and 400 meter medley events for males and females respectively. On the other hand, the lowest mean lactate value was recorded in long distance events of 1500 and 800 meters for males and females respectively and for all the age group divisions. Furthermore, swimming performance was related to peak lactate values which subsequently was independent of sex but dependent on age with higher lactate values and older age documented by the subjects with faster times. PMID:8699834

  14. 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)

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

    ERIC Educational Resources Information Center

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

    2008-01-01

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

  16. 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

  17. Autonomic predictors of Stroop performance in young and middle-aged adults.

    PubMed

    Mathewson, Karen J; Jetha, Michelle K; Drmic, Irene E; Bryson, Susan E; Goldberg, Joel O; Hall, Geoffrey B; Santesso, Diane L; Segalowitz, Sidney J; Schmidt, Louis A

    2010-06-01

    Although changes in autonomic activity have been extensively examined as responses to cognitive challenges, relatively few studies have used individual differences in autonomic parameters to predict executive performance in healthy adults. Here we examined baseline and task-related changes in heart rate and heart rate variability (measured by respiratory sinus arrhythmia (RSA)) to predict performance of a pictorial Stroop task in a group of 81 healthy adults aged 17-55. Greater autonomic reactivity (increased heart rate and reduced RSA for task performance) was associated with faster colour naming of faces in the Stroop task. Dividing the group by median age revealed that middle-aged adults reduced RSA to a greater degree than their younger counterparts in the context of equivalent performance across groups. Findings suggest that performance of executive function tasks that evoke attentional control may depend in part on the responsiveness of autonomic control parameters via age-dependent mechanisms. PMID:20193717

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

    PubMed Central

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

    2009-01-01

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

  19. Trajectories of Resilience during Dyadic Task Performance among Children Six to Seven Years of Age

    ERIC Educational Resources Information Center

    Mykkänen, Arttu; Kronqvist, Eeva-Liisa; Järvelä, Sanna

    2013-01-01

    The aim of this study is to analyse resilience displayed by young children in dyadic task performance situations. Data were collected by videotaping children (aged six to seven years; N?=?40) during a geometrical task performance. Results describe ways in which children confronted the challenges during task performance, and the order in which the…

  20. 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

  1. 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…

  2. 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…

  3. 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…

  4. 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…

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

    ERIC Educational Resources Information Center

    Robinson, James D.; Nussbaum, Jon F.

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

  6. 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.

  7. Lifecourse Adversity and Physical Performance across Countries among Men and Women Aged 65-74

    PubMed Central

    Sousa, Ana Carolina Patrício de Albuquerque; Guerra, Ricardo Oliveira; Thanh Tu, Mai; Phillips, Susan P.; Guralnik, Jack M.; Zunzunegui, Maria-Victoria

    2014-01-01

    Background This study examines the associations between lifecourse adversity and physical performance in old age in different societies of North and South America and Europe. Methods We used data from the baseline survey of the International Study of Mobility in Aging, conducted in: Kingston (Canada), Saint-Hyacinthe (Canada), Natal (Brazil), Manizales (Colombia) and Tirana (Albania). The study population was composed of community dwelling people between 65 and 74 years of age, recruiting 200 men and 200 women at each site. Physical Performance was assessed with the Short Physical Performance Battery (SPPB). Economic and social adversity was estimated from childhood adverse events, low education, semi-skilled occupations during adulthood and living alone and insufficient income in old age. Results A total of 1995 people were assessed. Low physical performance was associated with childhood social and economic adversity, semi-skilled occupations, living alone and insufficient income. Physical performance was lower in participants living in Colombia, Brazil and Albania than in Canada counterparts, despite adjustment for lifecourse adversity, age and sex. Conclusions We show evidence of the early origins of social and economic inequalities in physical performance during old age in distinct populations and for the independent and cumulative disadvantage of low socioeconomic status during adulthood and poverty and living alone in later life. PMID:25101981

  8. 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.

  9. 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.

  10. Sleep Duration and Age-Related Changes in Brain Structure and Cognitive Performance

    PubMed Central

    Lo, June C.; Loh, Kep Kee; Zheng, Hui; Sim, Sam K.Y.; Chee, Michael W.L.

    2014-01-01

    Study Objectives: To investigate the contribution of sleep duration and quality to age-related changes in brain structure and cognitive performance in relatively healthy older adults. Design: Community-based longitudinal brain and cognitive aging study using a convenience sample. Setting: Participants were studied in a research laboratory. Participants: Relatively healthy adults aged 55 y and older at study commencement. Interventions: N/A. Measurements and Results: Participants underwent magnetic resonance imaging and neuropsychological assessment every 2 y. Subjective assessments of sleep duration and quality and blood samples were obtained. Each hour of reduced sleep duration at baseline augmented the annual expansion rate of the ventricles by 0.59% (P = 0.007) and the annual decline rate in global cognitive performance by 0.67% (P = 0.050) in the subsequent 2 y after controlling for the effects of age, sex, education, and body mass index. In contrast, global sleep quality at baseline did not modulate either brain or cognitive aging. High-sensitivity C-reactive protein, a marker of systemic inflammation, showed no correlation with baseline sleep duration, brain structure, or cognitive performance. Conclusions: In healthy older adults, short sleep duration is associated with greater age-related brain atrophy and cognitive decline. These associations are not associated with elevated inflammatory responses among short sleepers. Citation: Lo JC, Loh KK, Zheng H, Sim SK, Chee MW. Sleep duration and age-related changes in brain structure and cognitive performance. SLEEP 2014;37(7):1171-1178. PMID:25061245

  11. 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

  12. Effects of aging and mild cognitive impairment on electrophysiological correlates of performance monitoring.

    PubMed

    Thurm, Franka; Antonenko, Daria; Schlee, Winfried; Kolassa, Stephan; Elbert, Thomas; Kolassa, Iris-Tatjana

    2013-01-01

    Performance monitoring tasks are suitable for investigating aging-related decline in executive functions. However, little is known about performance monitoring in premature pathological aging and mild cognitive impairment (MCI). This study recorded the error-related negativity (ERN) and the correct-related negativity (CRN) as indices of performance monitoring and compared these responses in older adults with MCI to the ones of younger and older adult controls. No differences in either ERN or CRN were found between younger and older adult controls. Compared to both control groups, we observed a more negatively pronounced CRN in MCI subjects. Only in this group did the amplitude of the CRN not differ from the one of the ERN. In general, larger differences between both components (i.e., ERN > CRN) were associated with better performances in cognitive tests requiring inhibition and executive control. These results indicate that electrophysiological correlates of performance monitoring (ERN and CRN) are differentially affected by aging and MCI. PMID:23455987

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

    PubMed

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

    2014-07-01

    Working memory is crucial for meeting the challenges of daily life and performing academic tasks, such as reading or arithmetic. Very preterm born children are at risk of low working memory capacity. The aim of this study was to examine the visuospatial working memory network of school-aged preterm children and to determine the effect of age and performance on the neural working memory network. Working memory was assessed in 41 very preterm born children and 36 term born controls (aged 7-12 years) using functional magnetic resonance imaging (fMRI) and neuropsychological assessment. While preterm children and controls showed equal working memory performance, preterm children showed less involvement of the right middle frontal gyrus, but higher fMRI activation in superior frontal regions than controls. The younger and low-performing preterm children presented an atypical working memory network whereas the older high-performing preterm children recruited a working memory network similar to the controls. Results suggest that younger and low-performing preterm children show signs of less neural efficiency in frontal brain areas. With increasing age and performance, compensational mechanisms seem to occur, so that in preterm children, the typical visuospatial working memory network is established by the age of 12 years. PMID:24631800

  14. 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

  15. Influence of cognitive abilities and age on word recall performance across trials and list segments.

    PubMed

    Krueger, Lacy E; Salthouse, Timothy A

    2011-01-01

    The influence of cognitive abilities and age on multitrial word recall performance was examined for different list segments (i.e., first, middle, and last) and across trials by having 2497 participants ages 18-98 complete a multitrial word list test along with reference cognitive ability tests. As expected, higher episodic memory ability was associated with better recall on all list segments but with a smaller influence for the last items on the early trials. Performance improved across trials, but there were no relations of the fluid intelligence construct that might be postulated to be associated with effective strategy implementation with any of the recall measures. Advanced age was associated with lower levels of performance, but very few of the age relations were significant after the variation in the reference cognitive abilities was controlled for. PMID:21977691

  16. 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. PMID:27317194

  17. 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. PMID:21210278

  18. 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

  19. Memory Self-Efficacy, Aging, and Memory Performance: The Roles of Effort and Persistence

    ERIC Educational Resources Information Center

    Wells, Gregory D.; Esopenko, Carrie

    2008-01-01

    The relative importance of mental effort, as indicated by strategy use, and persistence as potential mediators of the memory self-efficacy (MSE)/memory performance relationship was investigated within a sample of 26 adults aged 65 years and older. It was found that persistence but not strategy use was predictive of performance on a free-recall…

  20. 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…

  1. 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. PMID:25824621

  2. 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

  3. 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

  4. Differential aging of bite and jump performance in virgin and mated Teleogryllus commodus crickets.

    PubMed

    Lailvaux, Simon P; Zajitschek, Felix; Dessman, Josephine; Brooks, Robert

    2011-11-01

    Evolutionary theories of aging state that the force of natural selection declines with age, resulting in trait senescence. However, sexual selection theory predicts that costly traits that signal mate value should increase in expression as survival prospects decline. Mortality rates and fertility tend to show strong signatures of senescence, whereas sexual signaling traits increase with age, but how the expression of traits such as whole-organism performance measures that are subject to both sexual and nonsexual selection should change with age is unclear. We examined the effects of both a key life-history event (mating) and diet quality (male and female optimal diets) on aging in two whole-organism performance traits (bite force and jump take-off velocity) in male and female Teleogryllus commodus crickets. We found no evidence for diet effects on any of the measured traits. Aging effects were more evident in females than in males for both jumping and biting, and constitute a mix of senescence and terminal investment patterns depending on sex/mating class. Sex and mating therefore have important implications for resource allocation to performance traits, and hence for aging of those traits, and interactions between these two factors can result in complex changes in trait expression over individual lifetimes. PMID:22023581

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

    PubMed

    Bryce, Margaret S; Dodson, Chad S

    2013-03-01

    The cross-age effect refers to the finding of better memory for own- than other-age faces. We examined 3 issues about this effect: (1) Does it extend to the ability to monitor the likely accuracy of memory judgments for young and old faces? (2) Does it apply to source information that is associated with young and old faces? And (3) what is a likely mechanism underlying the cross-age effect? In Experiment 1, young and older adults viewed young and old faces appearing in different contexts. Young adults exhibited a cross-age effect in their recognition of faces and in their memory-monitoring performance for these faces. Older adults, by contrast, showed no age-of-face effects. Experiment 2 examined whether young adults' cross-age effect depends on or is independent of encoding a mixture of young and old faces. Young adults encoded either a mixture of young and old faces, a set of all young faces, or a set of all old faces. In the mixed-list condition we replicated our finding of young adults' superior memory for own-age faces; in the pure-list conditions, however, there were absolutely no differences in performance between young and old faces. The fact that the pure-list design abolishes the cross-age effect supports social-cognitive theories of this phenomenon. PMID:23066807

  6. 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

  7. The Impact of Age Stereotypes on Older Adults' Hazard Perception Performance and Driving Confidence.

    PubMed

    Chapman, Lyn; Sargent-Cox, Kerry; Horswill, Mark S; Anstey, Kaarin J

    2016-06-01

    This study examined the effect of age-stereotype threat on older adults' performance on a task measuring hazard perception performance in driving. The impact of age-stereotype threat in relation to the value participants placed on driving and pre- and post-task confidence in driving ability was also investigated. Eighty-six adults aged from 65 years of age completed a questionnaire measuring demographic information, driving experience, self-rated health, driving importance, and driving confidence. Prior to undertaking a timed hazard perception task, participants were exposed to either negative or positive age stereotypes. Results showed that age-stereotype threats, while not influencing hazard perception performance, significantly reduced post-driving confidence compared with pre-driving confidence for those in the negative prime condition. This finding builds on the literature that has found that stereotype-based influences cannot simply be understood in terms of performance outcomes alone and may be relevant to factors affected by confidence such as driving cessation decisions. PMID:24652925

  8. Age-related decline and diagnostic performance of more and less prevalent clinical cases.

    PubMed

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

    2016-08-01

    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 the effect of aging on physicians' diagnostic accuracy when diagnosing prevalent and less prevalent cases based on clinical vignettes. A mixed design was used to assess the influence of case prevalence (high vs. low) as a within-subjects factor, and age group as a between subjects factor (<30; n = 23, 30-39; n = 19, 40-49; n = 27, >50 years old; n = 19) on the diagnostic accuracy of 65 family physicians and 25 residents. Repeated Measure ANOVA revealed a significant effect of case prevalence (p < .001) and age group (p < .001). Post-hoc analyses revealed that younger physicians showed the best performance. This study did not demonstrate the positive effect of experience in older physicians. In line with previous studies on expertise development, findings of the present study suggest that skills should be actively maintained to assure a high performance level throughout one's lifespan. If not, performance level could gradually decline with age. PMID:26584578

  9. 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

  10. 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

  11. Effects of Aerobic Fitness on Aging-Related Changes of Interhemispheric Inhibition and Motor Performance

    PubMed Central

    McGregor, Keith M.; Nocera, Joe R.; Sudhyadhom, Atchar; Patten, Carolynn; Manini, Todd M.; Kleim, Jeffrey A.; Crosson, Bruce; Butler, Andrew J.

    2013-01-01

    Physical fitness has been long associated with maintenance and improvement of motor performance as we age. In particular, measures of psychomotor speed and motor dexterity tend to be higher in physically fit aging adults as compared to their sedentary counterparts. Using functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS), we explored the patterns of neural activity that may, in part, account for differences between individuals of varying physical fitness levels. In this study, we enrolled both sedentary and physically fit middle age (40–60) and younger (18–30) adults and measured upper extremity motor performance during behavioral testing. In a follow-up session, we employed TMS and fMRI to assess levels of interhemispheric communication during unimanual tasks. Results show that increased physical fitness is associated with better upper extremity motor performance on distal dexterity assessments and increased levels of interhemispheric inhibition in middle age adults. Further, the functional correlates of changes of ipsilateral activity appears to be restricted to the aging process as younger adults of varying fitness levels do not differ in hemispheric patterns of activity or motor performance. We conclude that sedentary aging confers a loss of interhemispheric inhibition that is deleterious to some aspects of motor function, as early as midlife, but these changes can be mediated by chronic engagement in aerobic exercise. PMID:24198784

  12. 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

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

    PubMed Central

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

    2013-01-01

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

  14. 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

  15. 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.

  16. 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. PMID:25592941

  17. Aging.

    PubMed

    Park, Dong Choon; Yeo, Seung Geun

    2013-09-01

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

  18. Aging

    PubMed Central

    Park, Dong Choon

    2013-01-01

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

  19. Functional neuroanatomy of sustained memory encoding performance in healthy aging and in Alzheimer's disease.

    PubMed

    Weis, Susanne; Leube, Dirk; Erb, Michael; Heun, Reinhard; Grodd, Wolfgang; Kircher, Tilo

    2011-07-01

    The aim of our study was to examine brain networks involved with sustaining memory encoding performance in healthy aging and in Alzheimer's disease (AD). Since different brain regions are affected by degradation in these two conditions, it might be conceivable that different compensation mechanisms occur to keep up memory performance in aging and in AD. Using an event-related functional magnetic resonance imaging (FMRI) design and a correlation analysis, 8 patients suffering from AD and 29 elderly control subjects were scanned while they studied a list of words for a subsequent memory test. Individual performance was assessed on the basis of a subsequent recognition test, and brain regions were identified where functional activations during study correlated with memory performance. In both groups, successful memory encoding performance was significantly correlated with the activation of the right frontal cortex. Furthermore, in healthy controls, there was a significant correlation of memory performance and the activation of the left medial and lateral temporal lobe. In contrast, in AD patients, increasing memory performance goes along with increasing activation of the hippocampus and a bilateral brain network including the frontal and temporal cortices. Our data show that in healthy aging and in AD, common and distinct compensatory mechanisms are employed to keep up a certain level of memory performance. Both in healthy aging and in patients with AD, an increased level of monitoring and control processes mediated by the (right) frontal lobe seems to be necessary to maintain a certain level of memory performance. In addition, memory performance in healthy older subjects seems to rely on an increased effort in encoding item-specific semantic and contextual information in lateral areas of the (left) temporal lobe. In AD patients, on the other hand, the maintenance of memory performance is related to an increase of activation of the (left) hippocampus in conjunction

  20. 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

  1. The effect of age on cognitive performance under the impact of vibration in a driving environment.

    PubMed

    Muzammil, Mohammad

    2004-01-01

    The effect of organismic variable age on human cognitive performance was studied under the impact of vibration in different automobile driving environments, namely city streets, rural roads and highways. Reaction time was measured in milliseconds through a human response measurement system specifically designed for the purpose. Results of the study showed that age had a significant effect in city street and rural road conditions. It was also found that the level of equivalent acceleration of vibration and a difficulty index significantly affected cognitive performance in all driving conditions. The organismic variable age observed to have a significant effect on task performance implied that youngsters and older people are stressed differently in specific environments of driving so proper stress management strategies should be evolved for them in order to minimize the number of accidents. PMID:15598358

  2. Coronary artery calcium and physical performance as determinants of mortality in older age: the AGES-Reykjavik Study

    PubMed Central

    von Bonsdorff, Mikaela B.; Groffen, Danielle A.I.; Vidal, Jean-Sebastien; Rantanen, Taina; Jonsson, Palmi V.; Garcia, Melissa; Aspelund, Thor; Eiriksdottir, Gudny; Siggeirsdóttir, Kristin; Launer, Lenore; Gudnason, Vilmundur; Harris, Tamara B.

    2013-01-01

    Background Coronary artery calcium (CAC) and physical performance have been shown to be associated with mortality, but it is not clear whether one of them modifies the association. We investigated the association between the extent of CAC and physical performance among older individuals and explored these individual and combined effects on cardiovascular disease (CVD) and non-CVD mortality. Methods We studied 4074 participants of the AGES-Reykjavik Study who were free from coronary heart disease, had a CAC score calculated from computed tomography scans and had data on mobility limitations and gait speed at baseline in 2002-2006 at a mean age of 76 years. Register-based mortality was available until 2009. Results Odds for mobility limitation and slow gait increased according to the extent of CAC. Altogether 645 persons died during the follow-up. High CAC, mobility limitation and slow gait were independent predictors of CVD and non-CVD mortality. The joint effect of CAC and gait speed on non-CVD mortality was synergistic, i.e. compared to those with low CAC and normal gait, the joint effect of high CAC and slow gait exceeded the additive effect of these individual exposures on non-CVD mortality. For CVD mortality, the effect was additive i.e. the joint effect of high CAC and slow gait did not exceed the sum of the individual exposures. Conclusions The extent of CAC and decreased physical performance were independent predictors of mortality and the joint presence of these risk factors increased the risk of non-CVD mortality above and beyond the individual effects. PMID:23414742

  3. 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

  4. 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

  5. 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

  6. Identifying the Optimal Age to Perform Newborn Screening for Hearing Loss in Uganda

    PubMed Central

    Walsh, M; Redshaw, E; Crossley, E; Phillips, C

    2015-01-01

    Background: Permanent congenital hearing loss affects up to 6/1000 births in developing countries. Currently, in Uganda there is no newborn screening for hearing loss (NSHL) program and no published work on this topic. Within the existing healthcare system there are two opportunities to deliver screening, at birth or 6 weeks of age when infants receive their immunizations. Aim: This study explored the outcomes of otoacoustic emission (OAE) testing in infants at birth and 6 weeks of age, to identify the optimal age for screening. Subjects and Methods: This cross-sectional pilot study recruited 60 consecutive infants from two health centres in Kampala, Uganda. Thirty infants were newborns recruited from the postnatal ward and 30 were aged 4–8 weeks from the immunization clinic, we performed OAE testing on all infants. Results: The results showed 56.7% (17/30) of newborn infants passed OAE testing compared with 90.0% (27/30) of the immunization infants, P < 0.01. Furthermore, of the 11 newborn infants aged ≥24 h of age 90.9% (10/11) passed, compared with the 19 infants <24 h of age where 37% (7/19) passed, P < 0.01. Conclusions: This study demonstrates a higher pass rate for OAE testing for infants ≥24 h of age compared to those <24 h of age. The overall lower pass rate of the newborn infants could be due to external ear debris and middle ear fluid compromising the OAE testing. These findings would support a NSHL programme in Uganda that offers screening to infants ≥24 h of age, to maximize the cost-effectiveness of the program. PMID:27057378

  7. 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

  8. Positive bias is a defining characteristic of aging to the same extent as declining performance.

    PubMed

    Simón, Teresa; Suengas, Aurora G; Ruiz-Gallego-Largo, Trinidad; Bandrés, Javier

    2013-01-01

    The aim of this study was to analyze whether one of the supposed gains of aging--positive bias--discriminates between young and older participants to the same extent as some of the losses in cognitive performance--recall and source monitoring--that come with age. Two age groups (N = 120)--young (M = 22.08, SD = 3.30) and older (M = 72.78, SD = 6.57)--carried out three tasks with varying levels of difficulty that included recall, recognition, and source monitoring using pictures, faces, and personal descriptors exchanged in a conversation as stimuli. The results of the discriminant analysis performed on 20 dependent variables indicated that six of them were key in discriminating between young and older participants. Younger participants outperformed older participants in recalling pictures, and in recognizing the descriptors exchanged in a conversation, as well as in monitoring their source. Just as important in discriminating between the two groups were the ability to recognize previously seen pictures, the likability rating they produced, and the recognition of faces with positive expressions--all superior in older participants. Thus, variables related to a positive bias--likability ratings and recognition of positive expressions--characterize the differences as a function of age as well as variables related to cognitive performance, such as recall and source monitoring. In addition, the likability ratings evoked by both pictures and faces were also significantly higher in the older participants with better cognitive performance than in those who performed poorly. This effect was not present in younger participants. The results are interpreted within the framework of socioemotional selectivity theory as evidence for a positive bias in old age. The connection between a positive bias and the maintenance of cognitive performance is also discussed. PMID:22963727

  9. 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

  10. Effects of vitamin E on cognitive performance during ageing and in Alzheimer's disease.

    PubMed

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

    2014-12-01

    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

  11. 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

  12. 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. PMID:24974663

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

    PubMed Central

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

    2015-01-01

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

  14. 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…

  15. 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…

  16. 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…

  17. 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,…

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

    PubMed Central

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

    2014-01-01

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

  19. 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)

  20. TESTOSTERONE, DEHYDROEPIANDROSTERONE, AND PHYSICAL PERFORMANCE IN OLDER MEN: RESULTS FROM THE MASSACHUSETTS MALE AGING STUDY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript examines the relationships of total testosterone (T), bioavailable T, dehydroepiandrosterone (DHEA), and DHEA sulfate (DHEAS) to measures of physical performance in a large, population-based, random sample of men. In the most recent wave of the Massachusetts Male Aging Study, measur...

  1. 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…

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

    ERIC Educational Resources Information Center

    Cortes, Kalena E.

    2006-01-01

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

  3. 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…

  4. Galanthamine Plus Estradiol Treatment Enhances Cognitive Performance in Aged Ovariectomized Rats

    PubMed Central

    Gibbs, R.B.; Chipman, A.M.; Hammond, R.; Nelson, D.

    2011-01-01

    We hypothesize that beneficial effects of estradiol on cognitive performance diminish with age and time following menopause due to a progressive decline in basal forebrain cholinergic function. This study tested whether galanthamine, a cholinesterase inhibitor used to treat memory impairment associated with Alzheimer’s disease, could enhance or restore estradiol effects on cognitive performance in aged rats that had been ovariectomized in middle-age. Rats were ovariectomized at 16–17 months of age. At 21–22 months of age rats began receiving daily injections of galanthamine (5 mg/day) or vehicle. After one week, half of each group also received 17ß-estradiol administered subcutaneously. Rats were then trained on a delayed matching to position (DMP) T-maze task, followed by an operant stimulus discrimination/reversal learning task. Treatment with galanthamine + estradiol significantly enhanced the rate of DMP acquisition and improved short-term delay-dependent spatial memory performance. Treatment with galanthamine or estradiol alone were without significant effect. Effects were task-specific in that galanthamine + estradiol treatment did not significantly improve performance on the stimulus discrimination/reversal learning task. In fact, estradiol was associated with a significant increase in incorrect responses on this task after reversal of the stimulus contingency. In addition, treatments did not significantly affect hippocampal choline acetyltransferase activity or acetylcholine release. This may be an effect of age, or possibly is related to compensatory changes associated with long-term cholinesterase inhibitor treatment. The data suggest that treating with a cholinesterase inhibitor can enhance the effects of estradiol on acquisition of a DMP task by old rats following a long period of hormone deprivation. This could be of particular benefit to older women who have not used hormone therapy for many years and are beginning to show signs of mild

  5. 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

  6. 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

  7. 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

    Torres-Unda, J, Zarrazquin, I, Gravina, L, Zubero, J, Seco, J, Gil, SM, Gil, J, and Irazusta, J. Basketball performance is related to maturity and relative age in elite adolescent players. J Strength Cond Res 30(5): 1325-1332, 2016-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

  8. 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

  9. 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

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

    PubMed

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

    2016-06-01

    Baker, TP, Candow, DG, and Farthing, JP. Effect of preexercise creatine ingestion on muscle performance in healthy aging males. J Strength Cond Res 30(6): 1763-1766, 2016-Preexercise creatine supplementation may have a beneficial effect on aging muscle performance. Using a double-blind, repeated measures, crossover design, healthy males (N = 9, 54.8 ± 4.3 years; 92.9 ± 11.5 kg; 179.2 ± 11.1 cm) were randomized to consume creatine (20 g) and placebo (20 g corn starch maltodextrin), on 2 separate occasions (7 days apart), 3 hours before performing leg press and chest press repetitions to muscle fatigue (3 sets at 70% 1-repetition maximum; 1 minute rest between sets). There was a set main effect (p ≤ 0.05) for the leg press and chest press with the number of repetitions performed decreasing similarly for creatine and placebo. These results suggest that a bolus ingestion of creatine consumed 3 hours before resistance exercise has no effect on upper or lower-body muscle performance in healthy aging males. PMID:26562708

  11. 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.

  12. 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. PMID:25250886

  13. 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.

  14. 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

  15. Age-related changes in functional network connectivity associated with high levels of verbal fluency performance.

    PubMed

    Marsolais, Yannick; Perlbarg, Vincent; Benali, Habib; Joanette, Yves

    2014-09-01

    The relative preservation of receptive language abilities in older adults has been associated with adaptive changes in cerebral activation patterns, which have been suggested to be task-load dependent. However, the effects of aging and task demands on the functional integration of neural networks contributing to speech production abilities remain largely unexplored. In the present functional neuroimaging study, data-driven spatial independent component analysis and hierarchical measures of integration were used to explore age-related changes in functional connectivity among cortical areas contributing to semantic, orthographic, and automated word fluency tasks in healthy young and older adults, as well as to assess the effect of age and task demands on the functional integration of a verbal fluency network. The results showed that the functional integration of speech production networks decreases with age, while at the same time this has a marginal effect on behavioral outcomes in high-performing older adults. Moreover, a significant task demand/age interaction was found in functional connectivity within the anterior and posterior subnetworks of the verbal fluency network. These results suggest that local changes in functional integration among cortical areas supporting lexical speech production are modulated by age and task demands. PMID:25014614

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

    PubMed Central

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

    2008-01-01

    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. PMID:18515368

  17. Changes in the muscle strength and functional performance of healthy women with aging

    PubMed Central

    Mousavikhatir, Roghayeh

    2012-01-01

    Background Lower limbs antigravity muscles weakness and decreased functional ability have significant role in falling. The aim of this study was to find the effects of aging on muscle strength and functional ability, determining the range of decreasing strength and functional ability and relationship between them in healthy women. Methods Across-section study was performed on 101 healthy women aged 21-80 years. The participants were divided into six age groups. The maximum isometric strength of four muscle groups was measured using a hand-held dynamometer bilaterally. The functional ability was measured with functional reach (FR), timed get up and go (TGUG), single leg stance (SLS), and stairs walking (SW) tests. Results Muscle strength changes were not significant between 21-40 years of age, but decreased significantly thereafter. Also, there was a significant relationship between muscle strength and functional ability in age groups. Conclusion Both muscle strength and functional ability is reduced as a result of aging, but the decrease in functional ability can be detected earlier. PMID:23482911

  18. 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.

  19. 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

  20. Age- and performance-related differences in hippocampal contributions to episodic retrieval.

    PubMed

    Sastre, Marcos; Wendelken, Carter; Lee, Joshua K; Bunge, Silvia A; Ghetti, Simona

    2016-06-01

    The goal of the present study was to investigate whether hippocampal contribution to episodic memory retrieval varies as a function of age (8-9 versus 10-11 versus adults), performance levels (high versus low) and hippocampal sub-region (head, body, tail). We examined fMRI data collected during episodic retrieval from a large sample (N=126). Participants judged whether a stimulus had been encoded previously, and, if so, which of three scenes it had been paired with (i.e., source judgment). For 8- to 9-years-olds as well as low-performing 10- to 11-year-olds, hippocampal activations did not reliably differentiate between trials on which item-scene associations were correctly recalled (correct source), incorrectly recalled (incorrect source), or trials on which the item was forgotten (miss trials). For high-performing 10-11-year olds and low-performing adults, selective hippocampal activation was observed for correct source relative to incorrect source and miss trials; this effect was observed across the entire hippocampus. For high-performing adults, hippocampal activation also distinguished between correct and incorrect source trialsl, but only in the hippocampal head, suggesting that good performance in adults is associated with more focal hippocampal recruitment. Thus, both age and performance are important factors for understanding the development of memory and hippocampal function. PMID:26875927

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

    PubMed

    Lin, Chia-Cheng; Whitney, Susan L; Loughlin, Patrick J; Furman, Joseph M; Redfern, Mark S; Sienko, Kathleen H; Sparto, Patrick J

    2015-04-01

    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

  2. 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

  3. 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

  4. 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

  5. Physical Activity throughout Adolescence and Cognitive Performance at 18 Years of Age

    PubMed Central

    Esteban-Cornejo, Irene; Hallal, Pedro C; Mielke, Grégore I; Menezes, Ana M B; Gonçalves, Helen; Wehrmeister, Fernando; Ekelund, Ulf; Rombaldi, Airton J

    2015-01-01

    Purpose To examine the prospective associations of physical activity at 11, 15 and 18 years of age with cognitive performance in young adulthood in a large birth cohort study from Brazil. Methods Participants were part of a large birth cohort study in Pelotas, Brazil (n = 3235 participants). Physical activity was self-reported at 11, 15 and 18 years and also was objectively measured at 18 years. Cognitive performance was assessed using an adapted Brazilian version of the short form of the Wechsler Adult Intelligence Scale (WAIS-III) at 18 years. Results At 11 years, participants in the middle tertile of self-reported physical activity presented a significantly higher cognitive performance score as compared to the lowest tertile. Physical activity at 15 years of age was unrelated to cognitive performance at 18 years. Self-reported physical activity was cross-sectionally positively associated with cognitive performance at 18 years (p<0.001). Data from objectively measured physical activity at 18 years showed that those in the highest moderate to vigorous physical activity tertile presented lower cognitive performance scores at 18 years as compared to those in the lowest tertile (−2.59; 95%CI: −3.41; −1.48). Analyses on changes in tertiles of physical activity showed that maintaining an intermediate physical activity level from 11 to 18 years and from 15 to 18 years was associated with higher cognitive performance score of 2.31 (95%CI: 0.71; 3.91) and 1.84 score (95%CI: 0.25; 3.42), respectively. Conclusion Physical activity throughout adolescence is associated with cognitive performance before adulthood. Adolescents who are active at moderate levels, specifically those who maintain these levels of physical activity, tend to show higher cognitive performance. However, high levels of physical activity might impair cognitive performance. PMID:25973558

  6. 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

  7. 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

    Hawkey, A, Griffiths, K, Babraj, J, and Cobley, JN. Whole-body vibration training and its application to age-related performance decrements: an exploratory analysis. J Strength Cond Res 30(2): 555-560, 2016-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. PMID:26244828

  8. 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. PMID:22505124

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

    PubMed

    Yeung, Dannii Y; Fung, Helene H

    2009-12-01

    The authors examined the impacts of selection, optimization, and compensation (SOC) strategies-elective selection, loss-based selection, optimization, and compensation-on job performance across adulthood. A cross-sectional survey (Study 1, N=355) and a 5-day experience sampling study (Study 2, N=87) were conducted to assess Chinese insurance sales workers' global and momentary employment of SOC strategies at work and compare the effectiveness of these strategies in predicting their job performance. Study 1 revealed that the use of compensation predicted higher performance maintenance among older workers, whereas the use of elective selection contributed positively to sales productivity for both age groups, with stronger association for younger workers. Study 2 demonstrated that the positive impact of SOC strategies on global and momentary measures of job performance differed across tasks with various difficulty levels. When the task was perceived as highly difficult, older workers' greater use of elective selection predicted higher self-rated task performance; however, the positive association was weaker among younger workers. Older workers' greater use of the 4 SOC strategies was positively associated with sales increases when the task was not difficult or moderately difficult, yet the relationship was negative when the task was highly difficult. A reverse pattern was observed among younger workers. This article contributes to the understanding of working adults' psychological adaptation to the process of aging and reveals the moderating role of task difficulty on the association between SOC strategies and performance outcomes. PMID:20025407

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

    USGS Publications Warehouse

    Serie, J.R.; Trauger, D.L.; Austin, J.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.

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

    PubMed Central

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

    2010-01-01

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

  12. Visual scanning behavior is related to recognition performance for own- and other-age faces

    PubMed Central

    Proietti, Valentina; Macchi Cassia, Viola; dell’Amore, Francesca; Conte, Stefania; Bricolo, Emanuela

    2015-01-01

    It is well-established that our recognition ability is enhanced for faces belonging to familiar categories, such as own-race faces and own-age faces. Recent evidence suggests that, for race, the recognition bias is also accompanied by different visual scanning strategies for own- compared to other-race faces. Here, we tested the hypothesis that these differences in visual scanning patterns extend also to the comparison between own and other-age faces and contribute to the own-age recognition advantage. Participants (young adults with limited experience with infants) were tested in an old/new recognition memory task where they encoded and subsequently recognized a series of adult and infant faces while their eye movements were recorded. Consistent with findings on the other-race bias, we found evidence of an own-age bias in recognition which was accompanied by differential scanning patterns, and consequently differential encoding strategies, for own-compared to other-age faces. Gaze patterns for own-age faces involved a more dynamic sampling of the internal features and longer viewing time on the eye region compared to the other regions of the face. This latter strategy was extensively employed during learning (vs. recognition) and was positively correlated to discriminability. These results suggest that deeply encoding the eye region is functional for recognition and that the own-age bias is evident not only in differential recognition performance, but also in the employment of different sampling strategies found to be effective for accurate recognition. PMID:26579056

  13. 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

  14. 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.

  15. 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.

  16. 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

  17. 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

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

    PubMed

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

    2016-02-01

    We assessed the impact of differing physical activity levels throughout the lifespan, using a musculoskeletal injury model, on the age-related changes in left ventricular (LV) parameters in active mice. Forty male mice (CBA/J) were randomly placed into one of three running wheel groups (transected CFL group, transected ATFL/CFL group, SHAM group) or a SHAM Sedentary group (SHAMSED). Before surgery and every 6 weeks after surgery, LV parameters were measured under 2.5 % isoflurane inhalation. Group effects for daily distance run was significantly greater for the SHAM and lesser for the ATLF/CFL mice (p = 0.013) with distance run decreasing with age for all mice (p < 0.0001). Beginning at 6 months of age, interaction (group × age) was noted with LV posterior wall thickness-to-radius ratios (h/r) where h/r increased with age in the ATFL/CFL and SHAMSED mice while the SHAM and CFL mice exhibited decreased h/r with age (p = 0.0002). Passive filling velocity (E wave) was significantly greater in the SHAM mice and lowest for the ATFL/CFL and SHAMSED mice (p < 0.0001) beginning at 9 months of age. Active filling velocity (A wave) was not different between groups (p = 0.10). Passive-to-active filling velocity ratio (E/A ratio) was different between groups (p < 0.0001), with higher ratios for the SHAM mice and lower ratios for the ATFL/CFL and SHAMSED mice in response to physical activity beginning at 9 months of age. Passive-to-active filling velocity ratio decreased with age (p < 0.0001). Regular physical activity throughout the lifespan improved LV structure, passive filling velocity, and E/A ratio by 6 to 9 months of age and attenuated any negative alterations throughout the second half of life. The diastolic filling differences were found to be significantly related to the amount of activity performed by 9 months and at the end of the lifespan. PMID:26803818

  19. 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. PMID:25089853

  20. 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,…

  1. 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

  2. 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

  3. 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. PMID:8575545

  4. 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

  5. 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…

  6. 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

  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. 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.

  9. 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

  10. Young children's understanding that promising guarantees performance: the effects of age and maltreatment.

    PubMed

    Lyon, Thomas D; Evans, Angela D

    2014-04-01

    Two studies, with 102 nonmaltreated 3- to 6-year-old children and 96 maltreated 4- to 7-year-old children, examined children's understanding of the relative strengths of "I promise," "I will," "I might," and "I won't," to determine the most age-appropriate means of eliciting a promise to tell the truth from child witnesses. Children played a game in which they chose which of 2 boxes would contain a toy after hearing story characters make conflicting statements about their intent to place a toy in each box (e.g., one character said "I will put a toy in my box" and the other character said "I might put a toy in my box"). Children understood "will" at a younger age than "promise." Nonmaltreated children understood that "will" is stronger than "might" by 3 years of age and that "promise" is stronger than "might" by 4 years of age. The youngest nonmaltreated children preferred "will" to "promise," whereas the oldest nonmaltreated children preferred "promise" to "will." Maltreated children exhibited a similar pattern of performance, but with delayed understanding that could be attributed to delays in vocabulary. The results support a modified oath for children: "Do you promise that you will tell the truth?". PMID:24127895

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

    PubMed

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

    2016-09-01

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

  12. 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

  13. Age at treatment and long-term performance results in medulloblastoma

    SciTech Connect

    Chin, H.W.; Maruyama, Y.

    1984-05-01

    Medulloblastoma is highly radioresponsive, and recent treatment results have improved greatly since the introduction of megavoltage machine in 1960s. There is increasing evidence for the potential cure of medulloblastoma if properly treated in its early stages. The curable group represents approximately 75% of diagnosed patients. Long-term treatment effects were examined in this study. The study reveals age-dependent late effects in learning ability; the patients less than 4-years-old at treatment had major learning problems; patients of 5 to 7 years old performed at satisfactory-to-low passing levels in school work; patients older than 8 years old had no major intellectual impairment. Short stature was common when growth potential was present at the time of therapy, but endocrine tests were generally negative. These observations indicate special educational requirement needs, especially for children treated at a young age.

  14. Individual Differences in School Mathematics Performance and Feelings of Difficulty: The Effects of Cognitive Ability, Affect, Age, and Gender.

    ERIC Educational Resources Information Center

    Efklides, Anastasia; Papadaki, Maria; Papantoniou, Georgia; Kiosseoglou, Gregoris

    1999-01-01

    Explores possible individual differences effects on school mathematics performance and feelings of difficulty (FOD) of 243 subjects, ages 13 to 15 years. Considers cognitive ability, affect, age, and gender. Finds that ability directly influenced performance whereas both ability and affect influenced FOD. Discusses the results. (CMK)

  15. Do Performance-based Health Measures Reflect Differences in Frailty Among Immigrants Age 50+ in Europe?

    PubMed Central

    Brothers, Thomas D.; Theou, Olga; Rockwood, Kenneth

    2014-01-01

    Background Life course influences, including country of residence and country of birth, are associated with frailty index scores. We investigated these associations using performance-based health measures. Methods Among 33,745 participants age 50+ (mean age 64.8 ± 10.1; 55% women) in the Survey of Health, Ageing, and Retirement in Europe, grip strength, delayed word recall, and semantic verbal fluency were assessed. Participants were grouped by country of residence (Northern/Western Europe or Southern/Eastern Europe), and by country of birth (native-born, immigrants born in low- and middle-income countries [LMICs], or immigrants born in high-income countries [HICs]). Results Participants in Southern/Eastern Europe had lower mean test scores than those in Northern/Western Europe, and their scores did not differ by country of birth group. In Northern/Western Europe, compared with native-born participants, LMIC-born immigrants demonstrated lower mean grip strength (32.8 ± 7.6 kg vs. 35.7 ± 7.7 kg), delayed recall (2.9 ± 1.9 vs. 3.6 ± 1.9), and verbal fluency scores (16.0 ± 6.9 vs. 20.3 ± 7.0). HIC-born immigrants had mean scores higher than LMIC-born immigrants, but lower than native-born participants (all p<.001). Conclusions Cognitive and motor performance, measured from late middle age, were associated with national income levels of both country of residence and country of birth. This was similar to previously observed differences in frailty index scores. PMID:25232369

  16. Early maternal age at first birth is associated with chronic diseases and poor physical performance in older age: cross-sectional analysis from the International Mobility in Aging Study

    PubMed Central

    2014-01-01

    Background Early maternal age at first birth and elevated parity may have long-term consequences for the health of women as they age. Both are known risk factors for obstetrical complications with lifelong associated morbidities. They may also be related to diabetes and cardiovascular disease development. Methods We examine the relationship between early maternal age at first birth, defined as ≤18 years of age, multiparity (>2 births), and poor physical performance (Short Physical Performance Battery ≤8) in community samples of women between 65 and 74 years of age from Canada, Albania, Colombia, and Brazil (N = 1040). Data were collected in 2012 to provide a baseline assessment for a longitudinal cohort called the International Mobility in Aging Study. We used logistic regression and general linear models to analyse the data. Results Early maternal age at first birth is significantly associated with diabetes, chronic lung disease, high blood pressure, and poor physical performance in women at older ages. Parity was not independently associated with chronic conditions and physical performance in older age. After adjustment for study site, age, education, childhood economic adversity and lifetime births, women who gave birth at a young age had 1.75 (95% CI: 1.17 – 2.64) the odds of poor SPPB compared to women who gave birth > 18 years of age. Adjustment for chronic diseases attenuated the association between early first birth and physical performance. Results were weaker in Colombia and Brazil, than Canada and Albania. Conclusions This study provides evidence that adolescent childbirth may increase the risk of developing chronic diseases and physical limitations in older age. Results likely reflect both the biological and social consequences of early childbearing and if the observed relationship is causal, it reinforces the importance of providing contraception and sex education to young women, as the consequences of early pregnancy may be life

  17. Allotransplantation for patients age ≥40 years with non-Hodgkin lymphoma: encouraging progression-free survival.

    PubMed

    McClune, Brian L; Ahn, Kwang Woo; Wang, Hai-Lin; Antin, Joseph H; Artz, Andrew S; Cahn, Jean-Yves; Deol, Abhinav; Freytes, César O; Hamadani, Mehdi; Holmberg, Leona A; Jagasia, Madan H; Jakubowski, Ann A; Kharfan-Dabaja, Mohamed A; Lazarus, Hillard M; Miller, Alan M; Olsson, Richard; Pedersen, Tanya L; Pidala, Joseph; Pulsipher, Michael A; Rowe, Jacob M; Saber, Wael; van Besien, Koen W; Waller, Edmund K; Aljurf, Mahmoud D; Akpek, Görgun; Bacher, Ulrike; Chao, Nelson J; Chen, Yi-Bin; Cooper, Brenda W; Dehn, Jason; de Lima, Marcos J; Hsu, Jack W; Lewis, Ian D; Marks, David I; McGuirk, Joseph; Cairo, Mitchell S; Schouten, Harry C; Szer, Jeffrey; Ramanathan, Muthalagu; Savani, Bipin N; Seftel, Matthew; Socie, Gérard; Vij, Ravi; Warlick, Erica D; Weisdorf, Daniel J

    2014-07-01

    Non-Hodgkin lymphoma (NHL) disproportionately affects older patients, who do not often undergo allogeneic hematopoietic cell transplantation (HCT). We analyzed Center for International Blood and Marrow Transplant Research data on 1248 patients age ≥40 years receiving reduced-intensity conditioning (RIC) or nonmyeloablative (NMA) conditioning HCT for aggressive (n = 668) or indolent (n = 580) NHL. Aggressive lymphoma was more frequent in the oldest cohort 49% for age 40 to 54 versus 57% for age 55 to 64 versus 67% for age ≥65; P = .0008). Fewer patients aged ≥65 had previous autografting (26% versus 24% versus 9%; P = .002). Rates of relapse, acute and chronic GVHD, and nonrelapse mortality (NRM) at 1 year post-HCT were similar in the 3 age cohorts (22% [95% confidence interval (CI), 19% to 26%] for age 40 to 54, 27% [95% CI, 23% to 31%] for age 55 to 64, and 34% [95% CI, 24% to 44%] for age ≥65. Progression-free survival (PFS) and overall survival (OS) at 3 years was slightly lower in the older cohorts (OS: 54% [95% CI, 50% to 58%] for age 40 to 54; 40% [95% CI, 36% to 44%] for age 55 to 64, and 39% [95% CI, 28% to 50%] for age ≥65; P < .0001). Multivariate analysis revealed no significant effect of age on the incidence of acute or chronic GVHD or relapse. Age ≥55 years, Karnofsky Performance Status <80, and HLA mismatch adversely affected NRM, PFS, and OS. Disease status at HCT, but not histological subtype, was associated with worse NRM, relapse, PFS, and OS. Even for patients age ≥55 years, OS still approached 40% at 3 years, suggesting that HCT affects long-term remission and remains underused in qualified older patients with NHL. PMID:24641829

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

    NASA Astrophysics Data System (ADS)

    Allen, Robert Grover

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

  19. 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.

  20. 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

  1. 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

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

    PubMed

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

    2016-03-01

    Ethnicity and cultural experience can affect neuropsychological performance, but they are rarely assessed in historical context. Attention measures are considered strongly biologically determined and therefore potentially culture-fair. In this study, we assessed the cross-cultural equivalence of Spanish and English versions of the Trail Making Test (TMT; Reitan, 1958, Perceptual and Motor Skills, 8, 271-276) and the Brief Test of Attention (BTA; Schretlen et al., 1996, The Clinical Neuropsychologist, 10, 80-89) in two large samples of Americans (N = 203) and Spaniards (N = 213), divided into younger and older subgroups. The older Spaniards lived under Franco's political regime (1936-1975), whereas the Americans never experienced such repression. Overall, TMT performance was culture-sensitive, whereas BTA performance was not. However, when both groups were stratified by age, cultural differences in TMT performance were restricted to older participants, suggesting that historical experience across generations might have contributed to the observed differences in cognitive performance. Even such basic cognitive processes as attention, working memory, and resource sharing might be shaped to some degree by historical experiences that contribute to cultural differences. PMID:25418760

  3. A Behavioral Paradigm to Evaluate Hippocampal Performance in Aged Rodents for Pharmacological and Genetic Target Validation

    PubMed Central

    Gerstein, Hilary; Hullinger, Rikki; Lindstrom, Mary J.; Burger, Corinna

    2013-01-01

    Aged-related cognitive ability is highly variable, ranging from unimpaired to severe impairments. The Morris water maze (a reliable tool for assessing memory) has been used to distinguish aged rodents that are superior learners from those that are learning impaired. This task, however, is not practical for pre- and post-pharmacological treatment, as the memory of the task is long lasting. In contrast, the object location memory task, also a spatial learning paradigm, results in a less robust memory that decays quickly. We demonstrate for the first time how these two paradigms can be used together to assess hippocampal cognitive impairments before and after pharmacological or genetic manipulations in rodents. Rats were first segregated into superior learning and learning impaired groups using the object location memory task, and their performance was correlated with future outcome on this task and on the Morris water maze. This method provides a tool to evaluate the effect of treatments on cognitive impairment associated with aging and neurodegenerative disorders. PMID:23667471

  4. 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

  5. Performance of aged cement-polymer composite immobilizing borate waste simulates during flooding scenarios

    NASA Astrophysics Data System (ADS)

    Eskander, S. B.; Bayoumi, T. A.; Saleh, H. M.

    2012-01-01

    An advanced composite of cement and water extended polyester based on the recycled Poly(ethylene terephthalate) waste was developed to incorporate the borate waste. Previous studies have reported the characterizations of the waste form (cement-polymer composite immobilizing borate waste simulates) after 28 days of curing time. The current work studied the performance of waste form aged for 7 years and subjected to flooding scenario during 260 days using three types of water. The state of waste form was assessed at the end of each definite interval of the water infiltration through visual examination and mechanical measurement. Scanning electron microscopy, infrared spectroscopy, X-ray diffraction and thermal analyses were used to investigate the changes that may occur in the microstructure of the waste form under aging and flooding effects. The actual experimental results indicated reasonable evidence for the durable waste form. Acceptable consistency was confirmed for the waste form even after aging 7 years and exposure to flooding scenario for 260 days.

  6. 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

  7. 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

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

    SciTech Connect

    Viswanathan, R.; Gandy, D.W.

    1999-10-01

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

  9. 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

  10. Improvement of skeletal muscle performance in ageing by the metabolic modulator Trimetazidine

    PubMed Central

    Pin, Fabrizio; Gorini, Stefania; Pontecorvo, Laura; Ferri, Alberto; Mollace, Vincenzo; Costelli, Paola; Rosano, Giuseppe

    2016-01-01

    Abstract Background The loss of muscle mass (sarcopenia) and the associated reduced muscle strength are key limiting factors for elderly people's quality of life. Improving muscle performance does not necessarily correlate with increasing muscle mass. In fact, particularly in the elderly, the main explanation for muscle weakness is a reduction of muscle quality rather than a loss of muscle mass, and the main goal to be achieved is to increase muscle strength. The effectiveness of Trimetazidine (TMZ) in preventing muscle functional impairment during ageing was assessed in our laboratory. Methods Aged mice received TMZ or vehicle for 12 consecutive days. Muscle function was evaluated at the end of the treatment by a grip test as well as by an inverted screen test at 0, 5, 7 and 12 days of TMZ treatment. After sacrifice, muscles were stored for myofiber cross‐sectional area assessment and myosin heavy chain expression evaluation by western blotting. Results Chronic TMZ treatment does not affect the mass of both gastrocnemius and tibialis anterior muscles, while it significantly increases muscle strength. Indeed, both latency to fall and grip force are markedly enhanced in TMZ‐treated versus untreated mice. In addition, TMZ administration results in higher expression of slow myosin heavy chain isoform and increased number of small‐sized myofibers. Conclusions We report here some data showing that the modulation of skeletal muscle metabolism by TMZ increases muscle strength in aged mice. Reprogramming metabolism might therefore be a strategy worth to be further investigated in view of improving muscle performance in the elderly. PMID:27239426

  11. Antioxidants and Quality of Aging: Further Evidences for a Major Role of TXNRD1 Gene Variability on Physical Performance at Old Age.

    PubMed

    Dato, Serena; De Rango, Francesco; Crocco, Paolina; Passarino, Giuseppe; Rose, Giuseppina

    2015-01-01

    Oxidative stress is a major determinant of human aging and common hallmark of age-related diseases. A protective role against free radicals accumulation was shown for thioredoxin reductase TrxR1, a key antioxidant selenoprotein. The variability of encoding gene (TXNRD1) was previously found associated with physical status at old age and extreme survival in a Danish cohort. To further investigate the influence of the gene variability on age-related physiological decline, we analyzed 9 tagging SNPs in relation to markers of physical (Activity of Daily Living, Hand Grip, Chair stand, and Walking) and cognitive (Mini Mental State Examination) status, in a Southern-Italian cohort of 64-107 aged individuals. We replicated the association of TXNRD1 variability with physical performance, with three variants (rs4445711, rs1128446, and rs11111979) associated with physical functioning after 85 years of age (p < 0.022). In addition, we found two SNPs borderline influencing longevity (rs4964728 and rs7310505) in our cohort, the last associated with health status and survival in Northern Europeans too. Overall, the evidences of association in a different population here reported extend the proposed role of TXNRD1 gene in modulating physical decline at extreme ages, further supporting the investigation of thioredoxin pathway in relation to the quality of human aging. PMID:26064428

  12. The largest human cognitive performance dataset reveals insights into the effects of lifestyle factors and aging

    PubMed Central

    Sternberg, Daniel A.; Ballard, Kacey; Hardy, Joseph L.; Katz, Benjamin; Doraiswamy, P. Murali; Scanlon, Michael

    2013-01-01

    Making new breakthroughs in understanding the processes underlying human cognition may depend on the availability of very large datasets that have not historically existed in psychology and neuroscience. Lumosity is a web-based cognitive training platform that has grown to include over 600 million cognitive training task results from over 35 million individuals, comprising the largest existing dataset of human cognitive performance. As part of the Human Cognition Project, Lumosity's collaborative research program to understand the human mind, Lumos Labs researchers and external research collaborators have begun to explore this dataset in order uncover novel insights about the correlates of cognitive performance. This paper presents two preliminary demonstrations of some of the kinds of questions that can be examined with the dataset. The first example focuses on replicating known findings relating lifestyle factors to baseline cognitive performance in a demographically diverse, healthy population at a much larger scale than has previously been available. The second example examines a question that would likely be very difficult to study in laboratory-based and existing online experimental research approaches at a large scale: specifically, how learning ability for different types of cognitive tasks changes with age. We hope that these examples will provoke the imagination of researchers who are interested in collaborating to answer fundamental questions about human cognitive performance. PMID:23801955

  13. The largest human cognitive performance dataset reveals insights into the effects of lifestyle factors and aging.

    PubMed

    Sternberg, Daniel A; Ballard, Kacey; Hardy, Joseph L; Katz, Benjamin; Doraiswamy, P Murali; Scanlon, Michael

    2013-01-01

    Making new breakthroughs in understanding the processes underlying human cognition may depend on the availability of very large datasets that have not historically existed in psychology and neuroscience. Lumosity is a web-based cognitive training platform that has grown to include over 600 million cognitive training task results from over 35 million individuals, comprising the largest existing dataset of human cognitive performance. As part of the Human Cognition Project, Lumosity's collaborative research program to understand the human mind, Lumos Labs researchers and external research collaborators have begun to explore this dataset in order uncover novel insights about the correlates of cognitive performance. This paper presents two preliminary demonstrations of some of the kinds of questions that can be examined with the dataset. The first example focuses on replicating known findings relating lifestyle factors to baseline cognitive performance in a demographically diverse, healthy population at a much larger scale than has previously been available. The second example examines a question that would likely be very difficult to study in laboratory-based and existing online experimental research approaches at a large scale: specifically, how learning ability for different types of cognitive tasks changes with age. We hope that these examples will provoke the imagination of researchers who are interested in collaborating to answer fundamental questions about human cognitive performance. PMID:23801955

  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. PMID:27616991

  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

    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. A homopolymer polymorphism in the TOMM40 gene contributes to cognitive performance in aging

    PubMed Central

    Hayden, Kathleen M.; McEvoy, Jill M.; Linnertz, Colton; Attix, Deborah; Kuchibhatla, Maragatha; Saunders, Ann M.; Lutz, Michael W.; Welsh-Bohmer, Kathleen A.; Roses, Allen D.; Chiba-Falek, Ornit

    2012-01-01

    Introduction A highly polymorphic T-homopolymer was recently discovered to be associated with late onset Alzheimer’s disease (LOAD) risk and age of onset. Objective To explore the effects of the polymorphic polyT tract (rs10524523, referred as ‘523’) on cognitive performance in cognitively healthy elderly. Methods 181 participants were recruited from local independent-living retirement communities. Informed consent was obtained and participants completed demographic questionnaires, a conventional paper and pencil neuropsychological battery, and the computerized Cambridge Neuropsychological Test Automated Battery (CANTAB). Saliva samples were collected for determination of the TOMM40 ‘523’ (S, L, VL) and the APOE (ε2, 3, 4) genotypes. From the initial sample of 181 individuals, 127 participants were eligible for the association analysis. Participants were divided into three groups based on ‘523’ genotypes (S/S, S/L-S/VL, and L/L-L/VL-VL/VL) Generalized linear models were used to evaluate the association between the ‘523’ genotypes and neuropsychological test performance. Analyses were adjusted for age, sex, education, depression, and APOE ε4 status. A planned sub analysis was undertaken to evaluate the association between ‘523’ genotypes and test performance in a sample restricted to APOE ε3 homozygotes. Results The S homozygotes performed better, although not significantly, than the S/L-S/VL and the VL/L-L/VL-VL/VL genotype groups on measures associated with memory (CANTAB Paired-Associate Learning, and VRM Free Recall) and executive function (CANTAB measures of Intra-Extradimensional set shifting). Follow-up analysis of APOEε 3 homozygotes only, showed that the S/S group performed significantly better than the S/VL group on measures of episodic memory (CANTAB Paired-Associate Learning and VRM Free Recall), attention (CANTAB RVP Latency) and executive function (Digit-Symbol substitution). The S/S group performed marginally better than the

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

    PubMed

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

    2011-10-01

    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 nonmated males. No significant differences were observed on the amount of spermatozoids between mated and nonmated males. PMID:21801728

  18. 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

  19. 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

  20. Effects of age, maturity and body dimensions on match running performance in highly trained under-15 soccer players.

    PubMed

    Buchheit, Martin; Mendez-Villanueva, Alberto

    2014-01-01

    The aim of the present study was to compare, in 36 highly trained under-15 soccer players, the respective effects of age, maturity and body dimensions on match running performance. Maximal sprinting (MSS) and aerobic speeds were estimated. Match running performance was analysed with GPS (GPSport, 1 Hz) during 19 international friendly games (n = 115 player-files). Total distance and distance covered >16 km h(-1) (D > 16 km h(-1)) were collected. Players advanced in age and/or maturation, or having larger body dimensions presented greater locomotor (Cohen's d for MSS: 0.5-1.0, likely to almost certain) and match running performances (D > 16 km h(-1): 0.2-0.5, possibly to likely) than their younger, less mature and/or smaller teammates. These age-, maturation- and body size-related differences were of larger magnitude for field test measures versus match running performance. Compared with age and body size (unclear to likely), maturation (likely to almost certainly for all match variables) had the greatest impact on match running performance. The magnitude of the relationships between age, maturation and body dimensions and match running performance were position-dependent. Within a single age-group in the present player sample, maturation had a substantial impact on match running performance, especially in attacking players. Coaches may need to consider players' maturity status when assessing their on-field playing performance. PMID:24786981

  1. 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.

  2. Nuclear power plant cable materials : review of qualification and currently available aging data for margin assessments in cable performance.

    SciTech Connect

    Celina, Mathias Christopher; Gillen, Kenneth Todd; Lindgren, Eric Richard

    2013-05-01

    A selective literature review was conducted to assess whether currently available accelerated aging and original qualification data could be used to establish operational margins for the continued use of cable insulation and jacketing materials in nuclear power plant environments. The materials are subject to chemical and physical degradation under extended radiationthermal- oxidative conditions. Of particular interest were the circumstances under which existing aging data could be used to predict whether aged materials should pass loss of coolant accident (LOCA) performance requirements. Original LOCA qualification testing usually involved accelerated aging simulations of the 40-year expected ambient aging conditions followed by a LOCA simulation. The accelerated aging simulations were conducted under rapid accelerated aging conditions that did not account for many of the known limitations in accelerated polymer aging and therefore did not correctly simulate actual aging conditions. These highly accelerated aging conditions resulted in insulation materials with mostlyinert' aging processes as well as jacket materials where oxidative damage dropped quickly away from the air-exposed outside jacket surface. Therefore, for most LOCA performance predictions, testing appears to have relied upon heterogeneous aging behavior with oxidation often limited to the exterior of the cable cross-section - a situation which is not comparable with the nearly homogenous oxidative aging that will occur over decades under low dose rate and low temperature plant conditions. The historical aging conditions are therefore insufficient to determine with reasonable confidence the remaining operational margins for these materials. This does not necessarily imply that the existing 40-year-old materials would fail if LOCA conditions occurred, but rather that unambiguous statements about the current aging state and anticipated LOCA performance cannot be provided based on original

  3. 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

  4. Effects of age, sex, and neuropsychological performance on financial decision-making.

    PubMed

    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

  5. 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

  6. Academic Performance and Substance Use among Students Aged 12 to 17: 2002, 2003, and 2004. The NSDUH Report. Issue 18

    ERIC Educational Resources Information Center

    Substance Abuse and Mental Health Services Administration, 2006

    2006-01-01

    This report examines the differences in self-reported academic performance (i.e., average grades in the last semester or grading period) among students aged 12 to 17 by gender, age, and substance use. All findings are annual averages based on combined 2002, 2003, and 2004 NSDUH data. Researchers found that the frequency of the use of alcohol and…

  7. The Effects of Age and Cue-Action Reminders on Event-Based Prospective Memory Performance in Preschoolers

    ERIC Educational Resources Information Center

    Kliegel, Matthias; Jager, Theodor

    2007-01-01

    The present study investigated event-based prospective memory in five age groups of preschoolers (i.e., 2-, 3-, 4-, 5-, and 6-year-olds). Applying a laboratory-controlled prospective memory procedure, the data showed that event-based prospective memory performance improves across the preschool years, at least between 3 and 6 years of age. However,…

  8. Aging Q3: an initiative to improve internal medicine residents' geriatrics knowledge, skills, and clinical performance.

    PubMed

    Moran, William P; Zapka, Jane; Iverson, Patty J; Zhao, Yumin; Wiley, M Kathleen; Pride, Pamela; Davis, Kimberly S

    2012-05-01

    A growing number of older adults coupled with a limited number of physicians trained in geriatrics presents a major challenge to ensuring quality medical care for this population. Innovations to incorporate geriatrics education into internal medicine residency programs are needed. To meet this need, in 2009, faculty at the Medical University of South Carolina developed Aging Q(3)-Quality Education, Quality Care, and Quality of Life. This multicomponent initiative recognizes the need for improved geriatrics educational tools and faculty development as well as systems changes to improve the knowledge and clinical performance of residents. To achieve these goals, faculty employ multiple intervention strategies, including lectures, rounds, academic detailing, visual cues, and electronic medical record prompts and decision support. The authors present examples from specific projects, based on care areas including vision screening, fall prevention, and caring for patients with dementia, all of which are based on the Assessing Care of Vulnerable Elders quality indicators. The authors describe the principles driving the design, implementation, and evaluation of the Aging Q(3) program. They present data from multiple sources that illustrate the effectiveness of the interventions to meet the knowledge, skill level, and behavior goals. The authors also address major challenges, including the maintenance of the teaching and modeling interventions over time within the context of demanding primary care and inpatient settings. This organized, evidence-based approach to quality improvement in resident education, as well as faculty leadership development, holds promise for successfully incorporating geriatrics education into internal medicine residencies. PMID:22450181

  9. Effects of Age and Schooling on Intellectual Performance: Estimates Obtained from Analysis of Continuous Variation in Age and Length of Schooling

    ERIC Educational Resources Information Center

    Cliffordson, Christina; Gustafsson, Jan-Eric

    2008-01-01

    The effects of age and schooling on different aspects of intellectual performance, taking track of study into account, are investigated. The analyses were based on military enlistment test scores, obtained by 48,269 males, measuring Fluid ability (Gf), Crystallized intelligence (Gc), and General visualization (Gv) ability. A regression method,…

  10. 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. PMID:26916066

  11. 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

  12. 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.

  13. Effects of Gestational Age at Birth on Cognitive Performance: A Function of Cognitive Workload Demands

    PubMed Central

    Jaekel, Julia; Baumann, Nicole; Wolke, Dieter

    2013-01-01

    Objective Cognitive deficits have been inconsistently described for late or moderately preterm children but are consistently found in very preterm children. This study investigates the association between cognitive workload demands of tasks and cognitive performance in relation to gestational age at birth. Methods Data were collected as part of a prospective geographically defined whole-population study of neonatal at-risk children in Southern Bavaria. At 8;5 years, n = 1326 children (gestation range: 23–41 weeks) were assessed with the K-ABC and a Mathematics Test. Results Cognitive scores of preterm children decreased as cognitive workload demands of tasks increased. The relationship between gestation and task workload was curvilinear and more pronounced the higher the cognitive workload: GA2 (quadratic term) on low cognitive workload: R2 = .02, p<0.001; moderate cognitive workload: R2 = .09, p<0.001; and high cognitive workload tasks: R2 = .14, p<0.001. Specifically, disproportionally lower scores were found for very (<32 weeks gestation) and moderately (32–33 weeks gestation) preterm children the higher the cognitive workload of the tasks. Early biological factors such as gestation and neonatal complications explained more of the variance in high (12.5%) compared with moderate (8.1%) and low cognitive workload tasks (1.7%). Conclusions The cognitive workload model may help to explain variations of findings on the relationship of gestational age with cognitive performance in the literature. The findings have implications for routine cognitive follow-up, educational intervention, and basic research into neuro-plasticity and brain reorganization after preterm birth. PMID:23717694

  14. Reproductive performance of high growth rate gilts inseminated at an early age.

    PubMed

    Kummer, Rafael; Bernardi, Mari Lourdes; Wentz, Ivo; Bortolozzo, Fernando Pandolfo

    2006-11-01

    The aim of this work was to determine if gilts, which have a high growth rate (GR) could be mated earlier without reducing the reproductive performance or increasing the culling rate up to the third parity. Gilts of Camborough 22 (C22, n=568) breeding were mated and allocated into three groups according to weight and age on the insemination day. G1 (n=164)-gilts with a GR>or=700 g/d and inseminated at <210 d. G2 (n=165)-gilts with a GR>or=700 g/d and inseminated at >or=210 d. G3 (n=239)-gilts with a GR<700 g/d and inseminated at >or=210 d. All females were fed ad libitum from 150 d on and were inseminated at their second estrus or later. The minimum weight at mating was 127 kg. Three parities were studied, with farrowing rate, litter size and culling rate being compared. At the first parity, G2 gilts produced, on average, one more piglet than the other groups (P<0.05). However, when analyzing three parities, there were no differences in total born (11.6 x 12.3 x 11.7), farrowing rate (87.1% x 88.7% x 89.8%) and culling rate (30.2% x 25.3% x 28.2%) among G1-G3 groups, respectively (P>0.05). In conclusion, gilts, which had a minimum weight of 127 kg can be inseminated at their second or greater estrus, between 185 and <210 d of age, without impairing their productive performance over three parities. PMID:16431043

  15. 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

  16. 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

  17. 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

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

    ERIC Educational Resources Information Center

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

    2006-01-01

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

  19. 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

  20. 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

  1. 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

  2. "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…

  3. 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

  4. 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. PMID:26562059

  5. 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.

  6. 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

  7. UCP3 polymorphisms, hand grip performance and survival at old age: Association analysis in two Danish middle aged and elderly cohorts

    PubMed Central

    Dato, Serena; Soerensen, Mette; Montesanto, Alberto; Lagani, Vincenzo; Passarino, Giuseppe; Christensen, Kaare; Christiansen, Lene

    2013-01-01

    An efficient uncoupling process is generally considered to have a protective effect on the aging muscle by slowing down its age-related decay. Genetic polymorphisms in the Uncoupling Protein 3 (UCP3) gene, whose product is mainly expressed in skeletal muscle, were suggested to be associated with hand grip (HG) performances in elderly populations. Considering the population specificity of the quality of aging, we aimed to add further support to this evidence by analyzing the association between four SNPs in the UCP3 gene and relative haplotypes in two large cohorts of middle aged (N = 708) and oldest old Danes (N = 908). We found that the variability at rs1685354 and rs11235972 was associated with HG levels both at single and haplotypic level in both cohorts. Furthermore, taking advantage of large cohort and period survival data of the oldest cohort, we tested the association of each SNP with survival at 10 years from the baseline visit. Interestingly, we found that allele A at rs11235972, associated in this cohort with lowest HG scores, influences also the survival patterns, with people carrying this allele showing higher mortality rates. On the whole, our work supports the role of UCP3 gene in functional status and survival at old age. PMID:22743239

  8. Dual Task Performance in Normal Aging: A Comparison of Choice Reaction Time Tasks

    PubMed Central

    Vaportzis, Eleftheria; Georgiou-Karistianis, Nellie; Stout, Julie C.

    2013-01-01

    This study examined dual task performance in 28 younger (18–30 years) and 28 older (>60 years) adults using two sets of choice reaction time (RT) tasks paired with digit tasks. Set one paired simple choice RT with digit forward; set two paired complex choice RT with digit backward. Each task within each set had easy and hard conditions. For the simple choice RT, participants viewed single letters and pressed a specified keyboard key if the letter was X or Z or a different key for other letters (easy). For the hard condition, there were 4 target letters (X, Z, O, Y). Digit forward consisted of 4 (easy) or 5 (hard) digits. For the complex choice RT, participants viewed 4×4 matrices of Xs and Os, and indicated whether four Xs (easy) or four Xs or four Os (hard) appeared in a row. Digit backward consisted of 3 (easy) or 4 (hard) digits. Within each set, participants performed every possible combination of tasks. We found that in the simple choice RT tasks older adults were significantly slower than, but as accurate as younger adults. In the complex choice RT tasks, older adults were significantly less accurate, but as fast as younger adults. For both age groups and both dual task sets, RT decreased and error rates increased with greater task difficulty. Older adults had greater dual task costs for error rates in the simple choice RT, whereas in the complex choice RT, it was the younger group that had greater dual task costs. Findings suggest that younger and older adults may adopt differential behavioral strategies depending on complexity and difficulty of dual tasks. PMID:23555937

  9. 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.

  10. 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

  11. 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

  12. 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

  13. Age-related differences in predictive response timing in children: evidence from regularly relative to irregularly paced reaction time performance.

    PubMed

    Debrabant, Julie; Gheysen, Freja; Vingerhoets, Guy; Van Waelvelde, Hilde

    2012-08-01

    Predictive timing refers to the anticipation and precise timing of planned motor responses. This study was performed to investigate children's predictive response timing abilities while accounting for confounding age-related effects of motor speed. Indices of predictive timing were evaluated for their contributions in motor skill proficiency as well. Eighty typically developing children in 4 age groups (5-6, 7-8, 9-10 and 11-12 years) performed a visuomotor reaction time (RT) test. Differences in speed and anticipatory responding at regularly relative to irregularly paced stimuli were evaluated as indices of predictive timing. Also, explicit timing and motor tests (M-ABC-2, VMI tracing, and KTK jumping) were administered. Significant faster responding for regularly versus irregularly paced stimuli was found from the ages of 9-10 years on. Better anticipatory responding behavior for regular in contrast with irregular stimuli was found to be present already at 7-8 years. Overall, predictive timing abilities increased across the 4 age groups. Also, inter-individual differences in the speed indices of predictive timing contributed to predicting VMI tracing and KTK jumping outcomes when controlling for age and overall motor response speed. In conclusion, predictive motor timing abilities increase during age 5 to 12 and correlate with motor skill performance. PMID:22494922

  14. 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. PMID:26707888

  15. 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…

  16. Effect of postmortem aging time on tumbling marination performance of broiler breast fillets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous data demonstrated that water-holding capacity (WHC), as measured by the salt-induced water uptake method, increases with aging up to 24 h postmortem in early-deboned chicken breast fillets (pectoralis major). Therefore, it was hypothesized that 24 h postmortem aging may enhance marination ...

  17. 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…

  18. 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…

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

    ERIC Educational Resources Information Center

    Muñoz, Carmen

    2014-01-01

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

  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. 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…

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

    NASA Astrophysics Data System (ADS)

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

    2015-09-01

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

  3. Longitudinal Study of Performance on the Ruff Figural Fluency Test in Persons Aged 35 Years or Older

    PubMed Central

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

    2015-01-01

    The Ruff Figural Fluency Test (RFFT) is a cognitive test to measure executive function. Longitudinal studies have shown that repeated testing improves performance on the RFFT. Such a practice effect may hinder the interpretation of test results in a clinical setting. Therefore, we investigated the longitudinal performance on the RFFT in persons aged 35–82 years. Performance on the RFFT was measured three times over an average follow-up period of six years in 2,515 participants of the Prevention of REnal and Vascular ENd-stage Disease (PREVEND) study in Groningen, the Netherlands: 53% men; mean age (SD), 53 (10) years. The effect of consecutive measurements on performance on the RFFT was investigated with linear multilevel regression models that also included age, gender, educational level and the interaction term consecutive measurement number x age as independent variables. It was found that the mean (SD) number of unique designs on the RFFT increased from 73 (26) at the first measurement to 79 (27) at the second measurement and to 83 (26) at the third measurement (p<0.001). However, the increase per consecutive measurement number was negatively associated with age and decreased with 0.23 per one-year increment of age (p<0.001). The increase per consecutive measurement number was not dependent on educational level. Similar results were found for the median (IQR) number of perseverative errors which showed a small but statistically significant increase with repeating testing: 7 (3–13) at the first measurement, 7 (4–14) at the second measurement and 8 (4–15) at the third measurement (ptrend = 0.002). In conclusion, the performance on the RFFT improved by repeating the test over an average follow-up period of three to six years. This practice effect was the largest in young adults and not dependent on educational level. PMID:25799403

  4. Allotransplantation for patients age 40 years and greater with non-Hodgkin Lymphoma (NHL): encouraging progression-free survival

    PubMed Central

    McClune, Brian L.; Ahn, Kwang Woo; Wang, Hai-Lin; Antin, Joseph H.; Artz, Andrew S.; Cahn, Jean-Yves; Deol, Abhinav; Freytes, César O.; Hamadani, Mehdi; Holmberg, Leona A.; Jagasia, Madan H.; Jakubowski, Ann A.; Kharfan-Dabaja, Mohamed A.; Lazarus, Hillard M.; Miller, Alan M.; Olsson, Richard; Pedersen, Tanya L.; Pidala, Joseph; Pulsipher, Michael A.; Rowe, Jacob M.; Saber, Wael; van Besien, Koen W.; Waller, Edmund K.; Aljurf, Mahmoud D.; Akpek, Görgun; Bacher, Ulrike; Chao, Nelson J.; Chen, Yi-Bin; Cooper, Brenda W.; Dehn, Jason; de Lima, Marcos J.; Hsu, Jack W.; Lewis, Ian D.; Marks, David I.; McGuirk, Joseph; Cairo, Mitchell S.; Schouten, Harry C.; Szer, Jeffrey; Ramanathan, Muthalagu; Savani, Bipin N.; Seftel, Matthew; Socie, Gérard; Vij, Ravi; Warlick, Erica D.; Weisdorf, Daniel J.

    2014-01-01

    Non-Hodgkin lymphomas (NHL) disproportionately affect older patients who uncommonly receive allogeneic hematopoietic cell transplantation (HCT). We analyzed CIBMTR data on 1248 patients ≥40 years receiving reduced-intensity conditioning (RIC) or non-myeloablative (NMA) HCT for aggressive (n=668) and indolent (n=580) NHL. Aggressive lymphoma was more frequent in the oldest cohort [(age 40–54) 49% vs. (55–64) 57% vs. (≥65) 67% p=0.0008]; fewer patients ≥65 had prior autografting [26% vs. 24% vs. 9%; p=0.002)]. Rates of relapse, acute and chronic GVHD and non-relapse mortality (NRM) at one year were similar [22%, 95% confidence interval (CI) 19–26%; 27%, 95% CI 23–31%; 34%, 95% CI 24–44%]. Progression-free (PFS) and overall (OS) survival at 3 years was slightly lower in older cohorts [OS:54%, 95% CI 50–58%; 40%, 95% CI 36–44%; 39%, 95% CI 28–50%; p<0.0001]. Multivariate analysis revealed no significant effect of age on acute or chronic GVHD or relapse. Age ≥55 years, Karnofsky performance status <80, and HLA-mismatch adversely impacted NRM, PFS, and OS. Disease status at HCT, but not histologic subtype, worsened NRM, relapse, PFS and OS. Even for patients ≥55 years, OS still approached 40% at 3 years suggesting HCT effects long-term remissions and remains underutilized in qualified older patients with NHL. PMID:24641829

  5. Age-Related Changes in Sleep and Circadian Rhythms: Impact on Cognitive Performance and Underlying Neuroanatomical Networks

    PubMed Central

    Schmidt, Christina; Peigneux, Philippe; Cajochen, Christian

    2012-01-01

    Circadian and homeostatic sleep-wake regulatory processes interact in a fine tuned manner to modulate human cognitive performance. Dampening of the circadian alertness signal and attenuated deterioration of psychomotor vigilance in response to elevated sleep pressure with aging change this interaction pattern. As evidenced by neuroimaging studies, both homeostatic sleep pressure and circadian sleep-wake promotion impact on cognition-related cortical and arousal-promoting subcortical brain regions including the thalamus, the anterior hypothalamus, and the brainstem locus coeruleus (LC). However, how age-related changes in circadian and homeostatic processes impact on the cerebral activity subtending waking performance remains largely unexplored. Post-mortem studies point to neuronal degeneration in the SCN and age-related modifications in the arousal-promoting LC. Alongside, cortical frontal brain areas are particularly susceptible both to aging and misalignment between circadian and homeostatic processes. In this perspective, we summarize and discuss here the potential neuroanatomical networks underlying age-related changes in circadian and homeostatic modulation of waking performance, ranging from basic arousal to higher order cognitive behaviors. PMID:22855682

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

    PubMed

    Gallagher, Michela; Burwell, Rebecca; Burchinal, Margaret

    2015-08-01

    The Morris water maze task was originally designed to assess the rat's ability to learn to navigate to a specific location in a relatively large spatial environment. This article describes new measures that provide information about the spatial distribution of the rat's search during both training and probe trial performance. The basic new measure optimizes the use of computer tracking to identify the rat's position with respect to the target location. This proximity measure was found to be highly sensitive to age-related impairment in an assessment of young and aged male Long-Evans rats. Also described is the development of a learning index that provides a continuous, graded measure of the severity of age-related impairment in the task. An index of this type should be useful in correlational analyses with other neurobiological or behavioral measures for the study of individual differences in functional/biological decline in aging. PMID:26214219

  7. [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

  8. 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

  9. 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

  10. 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

  11. 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…

  12. 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…

  13. 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…

  14. 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…

  15. 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

  16. 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

  17. 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

  18. 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

  19. Age and physical activity effects on reaction time and digit symbol substitution performance in cognitively active adults.

    PubMed

    Lupinacci, N S; Rikli, R E; Jones, C J; Ross, D

    1993-06-01

    University professors (N = 56), divided into two age groups (< 50 years and > 50 years) and two physical activity level groups (high and low), were tested on three tasks requiring increasingly complex cognitive processing--simple reaction time (SRT), choice reaction time (CRT), and on a digit symbol substitution test (DSST). A significant main effect for exercise, with high active subjects performing better than low active subjects, was found for SRT (p < .001) and CRT (p < .01) but not for DSST (p < .09). Significant main effects for age, with younger subjects performing better than older subjects, were found on DSST (p < .01) and CRT (p < .05) but not for SRT (p < .09). The observation that the effect of age was more pronounced with increasing task complexity is consistent with previous research. However, the tendency for exercise effects to decrease with increasing task complexity is not consistent with former findings, suggesting that perhaps the controlled high level of cognitive activity of subjects in this study may have offset the usual effects of exercise on information processing speed. No significant Age x Activity Level interactions were found on any of the dependent raw score data. However, compared to normative scores of the population at large, there was a slight increase in DSST percentile ranks with age for the older aerobically active professors, whereas a decrease occurred for the inactive subjects. PMID:8341837

  20. 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

  1. The relationship between the age of onset of musical training and rhythm synchronization performance: validation of sensitive period effects.

    PubMed

    Bailey, Jennifer A; Penhune, Virginia B

    2013-01-01

    A sensitive period associated with musical training has been proposed, suggesting the influence of musical training on the brain and behavior is strongest during the early years of childhood. Experiments from our laboratory have directly tested the sensitive period hypothesis for musical training by comparing musicians who began their training prior to age seven with those who began their training after age seven, while matching the two groups in terms of musical experience (Watanabe et al., 2007; Bailey and Penhune, 2010, 2012). Using this matching paradigm, the early-trained groups have demonstrated enhanced sensorimotor synchronization skills and associated differences in brain structure (Bailey et al., 2013; Steele et al., 2013). The current study takes a different approach to investigating the sensitive period hypothesis for musical training by examining a single large group of unmatched musicians (N = 77) and exploring the relationship between age of onset of musical training as a continuous variable and performance on the Rhythm Synchronization Task (RST), a previously used auditory-motor RST. Interestingly, age of onset was correlated with task performance for those who began training earlier, however, no such relationship was observed among those who began training in their later childhood years. In addition, years of formal training showed a similar pattern. However, individual working memory scores were predictive of task performance, regardless of age of onset of musical training. Overall, these results support the sensitive period hypothesis for musical training and suggest a non-linear relationship between age of onset of musical training and auditory-motor rhythm synchronization abilities, such that a relationship exists early in childhood but then plateaus later on in development, similar to maturational growth trajectories of brain regions implicated in playing music. PMID:24348323

  2. Scoring mode and age-related effects on youth soccer teams' defensive performance during small-sided games.

    PubMed

    Almeida, Carlos Humberto; Duarte, Ricardo; Volossovitch, Anna; Ferreira, António Paulo

    2016-07-01

    This study aimed to examine the scoring mode (line goal, double goal or central goal) and age-related effects on the defensive performance of youth soccer players during 4v4 small-sided games (SSGs). Altogether, 16 male players from 2 age groups (U13, n = 8, mean age: 12.61 ± 0.65 years; U15, n = 8, 14.86 ± 0.47 years) were selected as participants. In six independent sessions, participants performed the three SSGs each during 10-min periods. Teams' defensive performance was analysed at every instant ball possession was regained through the variables: ball-recovery type, ball-recovery sector, configuration of play and defence state. Multinomial logistic regression analysis used in this study revealed the following significant main effects of scoring mode and age: (1) line goal (vs. central goal) increased the odds of regaining possession through tackle and in the defensive midfield sector, and decreased the odds of successful interceptions; (2) double goal (vs. central goal) decreased the odds of regaining possession through turnover won and with elongated playing shapes; (3) the probability of regaining possession through interception significantly decreased with age. Moreover, as youth players move forward in age groups, teams tend to structurally evolve from elongated playing shapes to flattened shapes and, at a behavioural level, from defending in depth to more risky flattened configurations. Overall, by manipulating the scoring mode in SSGs, coaches can promote functional and coadaptive behaviours between teams not only in terms of configurations of play, but also on the pitch locations that teams explore to regain possession. PMID:26910232

  3. The relationship between the age of onset of musical training and rhythm synchronization performance: validation of sensitive period effects

    PubMed Central

    Bailey, Jennifer A.; Penhune, Virginia B.

    2013-01-01

    A sensitive period associated with musical training has been proposed, suggesting the influence of musical training on the brain and behavior is strongest during the early years of childhood. Experiments from our laboratory have directly tested the sensitive period hypothesis for musical training by comparing musicians who began their training prior to age seven with those who began their training after age seven, while matching the two groups in terms of musical experience (Watanabe et al., 2007; Bailey and Penhune, 2010, 2012). Using this matching paradigm, the early-trained groups have demonstrated enhanced sensorimotor synchronization skills and associated differences in brain structure (Bailey et al., 2013; Steele et al., 2013). The current study takes a different approach to investigating the sensitive period hypothesis for musical training by examining a single large group of unmatched musicians (N = 77) and exploring the relationship between age of onset of musical training as a continuous variable and performance on the Rhythm Synchronization Task (RST), a previously used auditory-motor RST. Interestingly, age of onset was correlated with task performance for those who began training earlier, however, no such relationship was observed among those who began training in their later childhood years. In addition, years of formal training showed a similar pattern. However, individual working memory scores were predictive of task performance, regardless of age of onset of musical training. Overall, these results support the sensitive period hypothesis for musical training and suggest a non-linear relationship between age of onset of musical training and auditory-motor rhythm synchronization abilities, such that a relationship exists early in childhood but then plateaus later on in development, similar to maturational growth trajectories of brain regions implicated in playing music. PMID:24348323

  4. Appraising and paying for performance: another look at an age-old problem.

    PubMed

    Kennedy, P W; Dresser, S G

    2001-12-01

    The basic notion of improving performance through management and appraisal is difficult to successfully implement in practice. These authors discuss some of the problems presented by tying pay to performance appraisals, offer suggestions for improving performance appraisals and outline some other approaches for employers to consider in setting goals and determining compensation. PMID:11817071

  5. Language, aging, and cognition: frontal aslant tract and superior longitudinal fasciculus contribute toward working memory performance in older adults.

    PubMed

    Rizio, Avery A; Diaz, Michele T

    2016-06-15

    Previous research has documented change in white matter tract integrity with increasing age. Both interhemispheric and intrahemispheric tracts that underlie language processing are susceptible to these age-related changes. The aim of the current study was to explore age and white matter integrity in language-related tracts as predictors of cognitive task performance in younger and older adults. To this end, we carried out principal component analyses of white matter tracts and confirmatory factor analysis of neuropsychological measures. We next carried out a series of regression analyses that used white matter components to predict scores on each of the neuropsychological components. For both younger and older adults, age was a significant predictor of processing speed and working memory. However, white matter integrity did not contribute independently toward these models. In older adults only, both age and a white matter component that included the bilateral frontal aslant tract and left superior longitudinal fasciculus were significant predictors of working memory. Taken together, these results extend our understanding of the contributions of language-related white matter structure to cognitive processing and highlight the effects of age-related differences in both frontal and dorsal tracts. PMID:27138951

  6. A Comparison of the Motor Performance of Black and Caucasian Girls Age 6-8

    ERIC Educational Resources Information Center

    Dinucci, James M.; Shows, David A.

    1977-01-01

    No significant differences in measures of flexibility, muscular endurance, cardiorespiratory endurance, speed, balance, or muscular power were found between black and Caucasian girls ages six, seven, and eight. Blacks were significantly superior on two agility measurements, and Caucasians better on shuttle run and grip strength. (MJB)

  7. Age and School-Type Differences in Children's Beliefs about School Performance

    ERIC Educational Resources Information Center

    Malmberg, Lars-Erik; Wanner, Brigitte; Little, Todd D.

    2008-01-01

    Age and school-type differences (primary school and three types of secondary school) in self-related beliefs about ability, effort, and difficulty were investigated in a study of 1723 Berlin youth. Consistent with selective ability-stratified schooling, multi-group structural equation models revealed: (1) mean-level belief differences reflecting…

  8. 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…

  9. 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…

  10. MODULATION OF HIPPOCAMPAL NEUROGENESIS AND COGNITIVE PERFORMANCE IN THE AGED RAT: THE BLUEBERRY EFFECT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The decline of memory with age is associated with a reduction in hippocampal neurogenesis, suggesting that this process may be an important factor in memory modulation. Thus, factors such as head injury, depression and stress that lead to decreases in neurogenesis are all associated with greater rat...

  11. 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…

  12. 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...

  13. Motor Performance of Women as a Function of Age and Physical Activity Level.

    ERIC Educational Resources Information Center

    Rikli, Roberta; Busch, Sharman

    Two studies compared motor skills of women in terms of the influence of age and activity level. In the first study, simple and choice reaction time, balance, flexibility, and grip strength of older active women were compared with that of older inactive women, and active and inactive younger women. Except for grip strength, scores of older active…

  14. 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…

  15. 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,…

  16. 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

  17. Influence of Age and Nutritional Status on Flight Performance of the Asian Tiger Mosquito Aedes albopictus (Diptera: Culicidae)

    PubMed Central

    Kaufmann, Christian; Collins, Lauren F.; Brown, Mark R.

    2013-01-01

    The Asian tiger mosquito, Aedes albopictus, is a competent vector for arboviruses and recently was implicated as the vector of the first autochthonous cases of dengue and chikungunya in southern Europe. The objective of this study was to analyze the flight performance of female Ae. albopictus of different ages that were starved, sugar-fed, or sugar-fed and blood-fed, using flight mills. After three days of starvation post emergence, females flew an average distance of 0.7 ± 0.5 km in 1.9 ± 1.5 h during a 16 h trial period, whereas sugar- or sugar- and blood-fed females of this age covered a significantly higher distance of around 3 km with a mean total flight time of around 6 h. The age of females (up to four weeks) had no effect on performance. The average of maximal continuous flight segments of sugar-fed (2.14 ± 0.69 h) and blood-fed (3.17 ± 0.82 h) females was distinctly higher than of starved females (0.38 ± 0.15 h) of which most flyers (83%) performed maximal flight segments that lasted no longer than 0.5 h. Overall, the results for the laboratory monitored flight performance of Ae. albopictus confirm their ability to disperse a few kilometres between breeding site and host. PMID:24404384

  18. 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

  19. 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. PMID:17239195

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

    ERIC Educational Resources Information Center

    Myerson, Joel; Robertson, Shannon; Hale, Sandra

    2007-01-01

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

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

    ERIC Educational Resources Information Center

    Wolfe, David E.

    1983-01-01

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

  2. Age-Specific Associations between Emotional Responses to Separation and Cognitive Performance in Infancy.

    ERIC Educational Resources Information Center

    Lewis, Marc D.; And Others

    1997-01-01

    Examined claim that associations between emotional responses to maternal separation and cognitive performance would change with cognitive development over the first year. Emphasized the measurement of separation and reunion distress. Found that emotional responses and cognitive performance may be linked by individual differences in self-regulation…

  3. 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…

  4. 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…

  5. Age-Related Performance on the Brixton Spatial Anticipation Test in Healthy Child and Adolescent Girls: A Preliminary Evaluation.

    PubMed

    Harvey, Lucy; Rose, Mark; Jonsson, Rosie; Lask, Bryan

    2016-01-01

    The Brixton Spatial Anticipation Test assesses individuals' cognitive flexibility in terms of rule detection and attainment. It has been used to assess executive functioning in both clinical and nonclinical adult samples. However, little is currently known about the suitability of this task for younger populations. The current study therefore aimed to provide an initial exploration of this task's suitability for young people. Brixton responses from a healthy sample of children and adolescents were presented to investigate performance in both rule detection and rule attainment, respectively. A convenience sample of 72 female participants (Mage = 14.95 years, SD = 1.53 years, range = 11-17 years; MIQ = 103.76, SD = 10.81) was studied. The sample was divided according to age into four groups (11-12 years, 13-14 years, 15 years, and 16-17 years) to allow for developmental trajectory. No significant age performance differences were found. Small effect sizes between age groups lend support to the null findings. The current study suggests that the Brixton task norms are suitable for use with individuals aged 11 to 17 years old. However, normative work is still needed in this area, incorporating an adult sample for comparison, to comment upon the developmental trajectory specific to this task. PMID:25928610

  6. Longitudinal development of frontoparietal activity during feedback learning: Contributions of age, performance, working memory and cortical thickness.

    PubMed

    Peters, Sabine; Van Duijvenvoorde, Anna C K; Koolschijn, P Cédric M P; Crone, Eveline A

    2016-06-01

    Feedback learning is a crucial skill for cognitive flexibility that continues to develop into adolescence, and is linked to neural activity within a frontoparietal network. Although it is well conceptualized that activity in the frontoparietal network changes during development, there is surprisingly little consensus about the direction of change. Using a longitudinal design (N=208, 8-27 years, two measurements in two years), we investigated developmental trajectories in frontoparietal activity during feedback learning. Our first aim was to test for linear and nonlinear developmental trajectories in dorsolateral prefrontal cortex (DLPFC), superior parietal cortex (SPC), supplementary motor area (SMA) and anterior cingulate cortex (ACC). Second, we tested which factors (task performance, working memory, cortical thickness) explained additional variance in time-related changes in activity besides age. Developmental patterns for activity in DLPFC and SPC were best characterized by a quadratic age function leveling off/peaking in late adolescence. There was a linear increase in SMA and a linear decrease with age in ACC activity. In addition to age, task performance explained variance in DLPFC and SPC activity, whereas cortical thickness explained variance in SMA activity. Together, these findings provide a novel perspective of linear and nonlinear developmental changes in the frontoparietal network during feedback learning. PMID:27104668

  7. 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

  8. Skilled performance tests and their use in diagnosing handedness and footedness at children of lower school age 8–10

    PubMed Central

    Musalek, Martin

    2015-01-01

    Previous research has shown that hand and foot preferences do not develop in parallel in children and it has been discovered that in children foot preference stabilizes later. Therefore, the aim of this study is to verify whether the differences in stabilization will also be manifested through less consistent results of selected skilled foot performance tests in a comparison with selected skilled hand performance tests. A total of 210 8–10 year old children from elementary schools were recruited for this study. Hand and foot preferences were first tested using hand and foot preference observable measure tasks; consequently, all participants performed four skilled hand performance tests and three foot performance tests. Unlike in complex skilled hand performance tests, which showed a significant convergent validity 0.56–0.89 with hand preference tasks, in complex skilled foot performance tests a very low convergent validity 0.25–0.46 with foot preference tasks was detected. The only skilled foot performance indicator which showed an acceptable convergent validity with foot preference tasks was the “foot tapping” test 0.65–0.85, which represents rather a gross motor activity. Moreover, further results of the tests suggest that complex or fine motor performance tests used for diagnosing laterality of the lower limb that have a manipulative character probably do not represent suitable indicators for children in the given age category. The same trend was revealed in both females and males. This indicates that the level of laterality assessed as difference in skilfulness between the preferred and the non-preferred limb in children in the given age group probably develops in the same way in both genders. PMID:25628579

  9. Same Modulation but Different Starting Points: Performance Modulates Age Differences in Inferior Frontal Cortex Activity during Word-Retrieval

    PubMed Central

    Meinzer, Marcus; Flaisch, Tobias; Seeds, Lauren; Harnish, Stacy; Antonenko, Daria; Witte, Veronica; Lindenberg, Robert; Crosson, Bruce

    2012-01-01

    The neural basis of word-retrieval deficits in normal aging has rarely been assessed and the few previous functional imaging studies found enhanced activity in right prefrontal areas in healthy older compared to younger adults. However, more pronounced right prefrontal recruitment has primarily been observed during challenging task conditions. Moreover, increased task difficulty may result in enhanced activity in the ventral inferior frontal gyrus (vIFG) bilaterally in younger participants as well. Thus, the question arises whether increased activity in older participants represents an age-related phenomenon or reflects task difficulty effects. In the present study, we manipulated task difficulty during overt semantic and phonemic word-generation and used functional magnetic resonance imaging to assess activity patterns in the vIFG in healthy younger and older adults (N = 16/group; mean age: 24 vs. 69 years). Both groups produced fewer correct responses during the more difficult task conditions. Overall, older participants produced fewer correct responses and showed more pronounced task-related activity in the right vIFG. However, increased activity during the more difficult conditions was found in both groups. Absolute degree of activity was correlated with performance across groups, tasks and difficulty levels. Activity modulation (difficult vs. easy conditions) was correlated with the respective drop in performance across groups and tasks. In conclusion, vIFG activity levels and modulation of activity were mediated by performance accuracy in a similar way in both groups. Group differences in the right vIFG activity were explained by performance accuracy which needs to be considered in future functional imaging studies of healthy and pathological aging. PMID:22438970

  10. Same modulation but different starting points: performance modulates age differences in inferior frontal cortex activity during word-retrieval.

    PubMed

    Meinzer, Marcus; Flaisch, Tobias; Seeds, Lauren; Harnish, Stacy; Antonenko, Daria; Witte, Veronica; Lindenberg, Robert; Crosson, Bruce

    2012-01-01

    The neural basis of word-retrieval deficits in normal aging has rarely been assessed and the few previous functional imaging studies found enhanced activity in right prefrontal areas in healthy older compared to younger adults. However, more pronounced right prefrontal recruitment has primarily been observed during challenging task conditions. Moreover, increased task difficulty may result in enhanced activity in the ventral inferior frontal gyrus (vIFG) bilaterally in younger participants as well. Thus, the question arises whether increased activity in older participants represents an age-related phenomenon or reflects task difficulty effects. In the present study, we manipulated task difficulty during overt semantic and phonemic word-generation and used functional magnetic resonance imaging to assess activity patterns in the vIFG in healthy younger and older adults (N = 16/group; mean age: 24 vs. 69 years). Both groups produced fewer correct responses during the more difficult task conditions. Overall, older participants produced fewer correct responses and showed more pronounced task-related activity in the right vIFG. However, increased activity during the more difficult conditions was found in both groups. Absolute degree of activity was correlated with performance across groups, tasks and difficulty levels. Activity modulation (difficult vs. easy conditions) was correlated with the respective drop in performance across groups and tasks. In conclusion, vIFG activity levels and modulation of activity were mediated by performance accuracy in a similar way in both groups. Group differences in the right vIFG activity were explained by performance accuracy which needs to be considered in future functional imaging studies of healthy and pathological aging. PMID:22438970

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

    NASA Astrophysics Data System (ADS)

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

    2015-10-01

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

  12. 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

  13. 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

  14. 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.

  15. 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. PMID:25761598

  16. 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

  17. 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

  18. 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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aging process is characterized by a series of changes in neurochemical functioning and in motor and cognitive performance. Exposure to 56Fe particles, a component of cosmic rays, produces accelerated aging such that these changes that are characteristic of aged organisms are observed in young a...

  20. 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. PMID:22755449

  1. 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. PMID:26666180

  2. 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…

  3. 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.

  4. 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…

  5. 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…

  6. Calving system, weaning age, and post-weaning management impacts on cow and steer calf performance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A 3-yr study evaluated late winter (LW), early spring (ES), and late spring (LS) calving systems (avg n . SC-1 . year-1 = 168) in conjunction with varied weaning strategies on beef cow and calf performance from Northern Great Plains rangelands. Calves in LW and ES systems were weaned at 190- and 240...

  7. Nonword Repetition Performance in School-Age Children with and without Language Impairment.

    ERIC Educational Resources Information Center

    Weismer, Susan Ellis; Tomblin, J. Bruce; Zhang, Xuyang; Buckwalter, Paula

    2000-01-01

    This study examined nonword repetition performance in 581 second graders participating in a longitudinal investigation of specific language impairment. Results indicated that children with language impairments, as well as those in intervention, exhibited deficient nonword repetition skills and that the Nonword Repetition Task is a culturally…

  8. Science at Age 13. Assessment of Performance Unit. Science Report for Teachers: 3.

    ERIC Educational Resources Information Center

    Murphy, Patricia; Schofield, Beta

    This report presents some of the results of two national surveys which assessed the performance of 13-year-old students in science. It includes an outline of the assessment framework; some of the questions which were written to match it; a description of how well, and how differently, students responded to the questions; and suggests how the…

  9. 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,…

  10. 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)

  11. 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...

  12. From numeracy to arithmetic: Precursors of arithmetic performance in children with cerebral palsy from 6 till 8 years of age.

    PubMed

    Van Rooijen, M; Verhoeven, L; Steenbergen, B

    2015-01-01

    Children with cerebral palsy (CP) are generally delayed in arithmetic compared to their peers. The development of early numeracy performance in children with CP is not yet evident, nor have the factors associated with change over time been identified. Therefore, we examined the development of numeracy in children with CP over a two year period and studied which cognitive factors were predictive of arithmetic performance. A longitudinal study with three measurement waves separated by one year was conducted. 56 children participated (37 boys, M=6.0 years, SD=.58). Standardized tasks were used to assess verbal- and visual-spatial working memory, executive functioning, fine motor skills and early numeracy performance. In addition, experimental tasks were developed to measure counting and arithmetic. The results showed that early numeracy performance of children with CP increased between 6 and 8 years of age. Structural equation modelling showed that early numeracy was strongly related to arithmetic performance at the consecutive year. Working memory, counting and fine motor skills were all positively related to early numeracy performance a year later. Furthermore, working memory and fine motor skills were precursors of the development of early numeracy. Considering the importance of numeracy and arithmetic in daily life and in academic and work success, children with CP could substantially benefit from intervention programs aimed at increasing working memory and early numeracy performance. PMID:26209773

  13. 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.

  14. Modification of dichotic listening (DL) performance by musico-linguistic abilities and age.

    PubMed

    Milovanov, Riia; Tervaniemi, Mari; Takio, Fiia; Hämäläinen, Heikki

    2007-07-01

    To increase our understanding of the phonemic processing skills of musical and non-musical subjects, the Dichotic Listening task was performed in children and adults with varying degrees of musical aptitude. The roles of maturation and musical training were also investigated. The results showed superior left ear monitoring skills among the adults who practised music regularly. This may indicate altered hemispheric functioning. Other musically talented subjects did not have the ability to control left ear functioning in an equal manner, for instance, the performance of musical children and their non-musical controls in the forced-left / left ear condition did not differ. Thus, regular music practice may have a modulatory effect on the brain's linguistic organization and therefore, the beneficial effects of music on other cognitive skills should not be underestimated. PMID:17509539

  15. 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,…).

  16. 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.

  17. 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

  18. 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

  19. 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

  20. Performance and Aging Studies of BaBar Resistive Plate Chambers

    SciTech Connect

    Band, H.R.; Hollar, J.; Tan, P.; Anulli, F.; Baldini, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Patteri, P.; Piccolo, M.; Zallo, A.; Cheng, C.H.; Lange, D.J.; Wright, D.M.; Messner, R.; Wisniewski, W.J.; Pappagallo, M.; Andreotti, M.; Bettoni, D.; Calabrese, R.; Cibinetto, G.; /Wisconsin U., Madison /Frascati /LLNL, Livermore /SLAC /Bari U. /INFN, Bari /Ferrara U. /INFN, Ferrara /Genoa U. /INFN, Genoa /Naples U. /INFN, Naples /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Rome U. /INFN, Rome /Oregon U. /UC, Riverside

    2006-10-13

    The BaBar detector is currently operating nearly 200 Resistive Plate Chambers (RPCs), constructed as part of an upgrade of the forward endcap muon detector in 2002. Although the average RPC efficiency remains high, numerous changes in the RPC performance (increased currents and rates) have been observed. A few of the highest rate RPCs have suffered efficiency losses of more than 15%. Several types of efficiency loss have been observed. Tests with humidified gas have shown that some of the lost efficiency is recoverable. However, efficiency losses in the highest rate regions have not yet improved with humid gases.

  1. Skeletal muscle myofilament adaptations to aging, disease, and disuse and their effects on whole muscle performance in older adult humans

    PubMed Central

    Miller, Mark S.; Callahan, Damien M.; Toth, Michael J.

    2014-01-01

    Skeletal muscle contractile function declines with aging, disease, and disuse. In vivo muscle contractile function depends on a variety of factors, but force, contractile velocity and power generating capacity ultimately derive from the summed contribution of single muscle fibers. The contractile performance of these fibers are, in turn, dependent upon the isoform and function of myofilament proteins they express, with myosin protein expression and its mechanical and kinetic characteristics playing a predominant role. Alterations in myofilament protein biology, therefore, may contribute to the development of functional limitations and disability in these conditions. Recent studies suggest that these conditions are associated with altered single fiber performance due to decreased expression of myofilament proteins and/or changes in myosin-actin cross-bridge interactions. Furthermore, cellular and myofilament-level adaptations are related to diminished whole muscle and whole body performance. Notably, the effect of these various conditions on myofilament and single fiber function tends to be larger in older women compared to older men, which may partially contribute to their higher rates of disability. To maintain functionality and provide the most appropriate and effective countermeasures to aging, disease, and disuse in both sexes, a more thorough understanding is needed of the contribution of myofilament adaptations to functional disability in older men and women and their contribution to tissue level function and mobility impairment. PMID:25309456

  2. 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.

  3. 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. PMID:23796063

  4. 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

  5. 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

  6. In vivo performance of Italian Heavy Draft Horse weanlings fed two protein levels and slaughtered at two ages.

    PubMed

    Mantovani, R; Guzzo, N; Sartori, C; Bailoni, L

    2014-11-01

    This study aimed at evaluating in vivo performance, growth parameters, intakes, dressing percentage, and blood parameters in Italian Heavy Draft Horse (IHDH) weanlings fed 2 CP levels up to the 2 typical ages of slaughter. Forty-one weanlings were grouped in 8 pens according to sex, age, and BW. After a transition period, animals were randomly assigned to 2 isoenergetic diets containing different CP levels: 10.6 and 11.2% CP in DM for low protein (LP) and 13.2 and 14.7% CP in DM for high protein (HP) diets in the first and second phase, respectively. About half of the animals (n = 22) were slaughtered when aged 13 mo (end of first phase); the remaining animals (n = 19) were slaughtered at 18 mo (end of second phase). Animals were weighed, measured for withers height, and scored in vivo for fleshiness and BCS at 3 wk intervals. Feed intake in each pen was measured weekly, and feed samples were collected every 2 mo. Blood samples from venous jugular were collected in both phases to analyze plasma protein, urea, glucose, bilirubin, hepatic enzymes, and mineral content. Growth parameters were estimated within phase by modeling BW as a function of age using fourth-degree Legendre polynomials. During the first phase, a different linear coefficient (P = 0.051) for the growth curve was observed between females fed a HP or a LP diet, while males showed differences only on quadratic and cubic Legendre coefficients. However, no significant differences were detected in ADG between the CP levels and sexes. In the second phase, Legendre coefficients were not different between treatments for the remaining weanlings, and once again no differences were found on ADG. The DM intake was influenced by diets in both periods, greater in the HP diet as compared with the LP diet (P < 0.001). No differences due to diet were observed for fleshiness or BCS scores at the end of each phase or in the dressing percentage at slaughter. As expected, plasma urea was greater (P < 0.001) in animals

  7. Relating Memory To Functional Performance In Normal Aging to Dementia Using Hierarchical Bayesian Cognitive Processing Models

    PubMed Central

    Shankle, William R.; Pooley, James P.; Steyvers, Mark; Hara, Junko; Mangrola, Tushar; Reisberg, Barry; Lee, Michael D.

    2012-01-01

    Determining how cognition affects functional abilities is important in Alzheimer’s disease and related disorders (ADRD). 280 patients (normal or ADRD) received a total of 1,514 assessments using the Functional Assessment Staging Test (FAST) procedure and the MCI Screen (MCIS). A hierarchical Bayesian cognitive processing (HBCP) model was created by embedding a signal detection theory (SDT) model of the MCIS delayed recognition memory task into a hierarchical Bayesian framework. The SDT model used latent parameters of discriminability (memory process) and response bias (executive function) to predict, simultaneously, recognition memory performance for each patient and each FAST severity group. The observed recognition memory data did not distinguish the six FAST severity stages, but the latent parameters completely separated them. The latent parameters were also used successfully to transform the ordinal FAST measure into a continuous measure reflecting the underlying continuum of functional severity. HBCP models applied to recognition memory data from clinical practice settings accurately translated a latent measure of cognition to a continuous measure of functional severity for both individuals and FAST groups. Such a translation links two levels of brain information processing, and may enable more accurate correlations with other levels, such as those characterized by biomarkers. PMID:22407225

  8. Morphology of the small intestinal mucosal surface of broilers in relation to age, diet formulation, small intestinal microflora and performance.

    PubMed

    van Leeuwen, P; Mouwen, J M V M; van der Klis, J D; Verstegen, M W A

    2004-02-01

    1. Three experiments were performed to relate morphological characteristics of the small intestinal mucosal surface to age, dietary factors, small intenstinal microflora and performance of broilers. Characterisation of the small intestinal mucosal surface using a dissecting microscope was based on the orientation of the villi, villus shape and the presence of convoluted villi. 2. In Trial 1, the morphological changes of the mucosal surface were studied weekly in the period from 7 to 28 d of age. At d 7 mainly tongue- and leaf-shaped villi together with some ridge-shaped ones were observed in the middle section of the small intestine, displaying a regular zigzag pattern on 53% of the mucosal surface. During the period from d 7 to 14, the area with ridge-shaped villi increased from 7 to 63% and did not change significantly over the next 2 weeks. 3. In Trial 2, three protein sources, soy isolate (SI), wheat gluten (WG), hydrolysed wheat gluten (HWG) and SI with added L-glutamine (SI + Gln), were studied with respect to their effect as dietary components on villus morphology in the mid-small intestine and performance. Diets were fed with (0 to 14 d) and without pectin (14 to 21 d). Feed conversion ratio on the HWG diet improved in comparison to the native WG diet. During the period 0 to 14 d of age the mucosal area with zigzag-oriented villi increased when the pectin diet was supplemented with Gln. Moreover, weight gain of birds fed the SI + Gln diet increased in the period 41 to 21 d. 4. In Trial 3, a study was made of the morphological response of the villi to a stimulation of microbial activity in the digesta after addition of highly methylated pectin to the soybean meal (SBM) diet. This was performed with and without inoculation of a non-virulent Salmonella typhimurium on d 7. By d 21 the birds fed the pectin diet showed impaired weight gain and higher feed conversion. The pectin affected the mucosal surface by decreasing the area with the zigzag pattern and

  9. Diagnosing dementia and normal aging: clinical relevance of brain ratios and cognitive performance in a Brazilian sample.

    PubMed

    Chaves, M L; Ilha, D; Maia, A L; Motta, E; Lehmen, R; Oliveira, L M

    1999-09-01

    The main objective of the present study was to evaluate the diagnostic value (clinical application) of brain measures and cognitive function. Alzheimer and multi-infarct patients (N = 30) and normal subjects over the age of 50 (N = 40) were submitted to a medical, neurological and cognitive investigation. The cognitive tests applied were Mini-Mental, word span, digit span, logical memory, spatial recognition span, Boston naming test, praxis, and calculation tests. The brain ratios calculated were the ventricle-brain, bifrontal, bicaudate, third ventricle, and suprasellar cistern measures. These data were obtained from a brain computer tomography scan, and the cutoff values from receiver operating characteristic curves. We analyzed the diagnostic parameters provided by these ratios and compared them to those obtained by cognitive evaluation. The sensitivity and specificity of cognitive tests were higher than brain measures, although dementia patients presented higher ratios, showing poorer cognitive performances than normal individuals. Normal controls over the age of 70 presented higher measures than younger groups, but similar cognitive performance. We found diffuse losses of tissue from the central nervous system related to distribution of cerebrospinal fluid in dementia patients. The likelihood of case identification by functional impairment was higher than when changes of the structure of the central nervous system were used. Cognitive evaluation still seems to be the best method to screen individuals from the community, especially for developing countries, where the cost of brain imaging precludes its use for screening and initial assessment of dementia. PMID:10464391

  10. Predicting Curriculum and Test Performance at Age 11 Years from Pupil Background, Baseline Skills and Phonological Awareness at Age 5 Years

    ERIC Educational Resources Information Center

    Savage, Robert; Carless, Sue; Ferraro, Vittoria

    2007-01-01

    Background: Phonological awareness tests are amongst the best predictors of literacy and predict outcomes of Key Stage 1 assessment of the National Curriculum in England at age 7. However, it is unknown whether their ability to predict National Curricular outcomes extends to Key Stage 2 assessments given at age 11, or also whether the predictive…

  11. 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

  12. Performance And Agreement Of Risk Stratification Instruments For Postoperative Delirium In Persons Aged 50 Years Or Older

    PubMed Central

    Jansen, Carolien J.; Absalom, Anthony R.; de Bock, Geertruida H.; van Leeuwen, Barbara L.; Izaks, Gerbrand J.

    2014-01-01

    Several risk stratification instruments for postoperative delirium in older people have been developed because early interventions may prevent delirium. We investigated the performance and agreement of nine commonly used risk stratification instruments in an independent validation cohort of consecutive elective and emergency surgical patients aged ≥50 years with ≥1 risk factor for postoperative delirium. Data was collected prospectively. Delirium was diagnosed according to DSM-IV-TR criteria. The observed incidence of postoperative delirium was calculated per risk score per risk stratification instrument. In addition, the risk stratification instruments were compared in terms of area under the receiver operating characteristic (ROC) curve (AUC), and positive and negative predictive value. Finally, the positive agreement between the risk stratification instruments was calculated. When data required for an exact implementation of the original risk stratification instruments was not available, we used alternative data that was comparable. The study population included 292 patients: 60% men; mean age (SD), 66 (8) years; 90% elective surgery. The incidence of postoperative delirium was 9%. The maximum observed incidence per risk score was 50% (95%CI, 15–85%); for eight risk stratification instruments, the maximum observed incidence per risk score was ≤25%. The AUC (95%CI) for the risk stratification instruments varied between 0.50 (0.36–0.64) and 0.66 (0.48–0.83). No AUC was statistically significant from 0.50 (p≥0.11). Positive predictive values of the risk stratification instruments varied between 0–25%, negative predictive values between 89–95%. Positive agreement varied between 0–66%. No risk stratification instrument showed clearly superior performance. In conclusion, in this independent validation cohort, the performance and agreement of commonly used risk stratification instruments for postoperative delirium was poor. Although some caution is

  13. 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. PMID:24169095

  14. Age at the onset of senescence in birds and mammals is predicted by early-life performance

    PubMed Central

    Péron, Guillaume; Gimenez, Olivier; Charmantier, Anne; Gaillard, Jean-Michel; Crochet, Pierre-André

    2010-01-01

    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. PMID:20427343

  15. 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

  16. 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

  17. 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.

  18. Donepezil Treatment Restores the Ability of Estradiol to Enhance Cognitive Performance in Aged Rats: Evidence for the Cholinergic Basis of the Critical Period Hypothesis

    PubMed Central

    Gibbs, R.B.; Mauk, R.; Nelson, D.; Johnson, D.A.

    2009-01-01

    Recent studies suggest that the ability of estradiol to enhance cognitive performance diminishes with age and/or time following loss of ovarian function. We hypothesize that this is due, in part, to a decrease in basal forebrain cholinergic function. This study tested whether donepezil, a cholinesterase inhibitor, could restore estradiol effects on cognitive performance in aged rats that had been ovariectomized as young adults. Rats were ovariectomized at 3 months of age, and then trained on a delayed matching to position (DMP) T-maze task, followed by a configural association (CA) operant condition task, beginning at 12–17 or 22–27 months of age. Three weeks prior to testing, rats started to receive either donepezil or vehicle. After one week, half of each group also began receiving estradiol. Acclimation and testing began seven days later and treatment continued throughout testing. Estradiol alone significantly enhanced DMP acquisition in middle-aged rats, but not in aged rats. Donepezil alone had no effect on DMP acquisition in either age group; however, donepezil treatment restored the ability of estradiol to enhance DMP acquisition in aged rats. This effect was due largely to a reduction in the predisposition to adopt a persistent turn strategy during acquisition. These same treatments did not affect acquisition of the CA task in middle-aged rats, but did have small but significant effects on response time in aged rats. The data are consistent with the idea that estrogen effects on cognitive performance are task specific, and that deficits in basal forebrain cholinergic function are responsible for the loss of estradiol effect on DMP acquisition in aged ovariectomized rats. In addition, the data suggest that enhancing cholinergic function pharmacologically can restore the ability of estradiol to enhance acquisition of the DMP task in very old rats following long periods of hormone deprivation. Whether donepezil has similar restorative effects on other

  19. 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

  20. Relationship of Physical Performance with Body Composition and Bone Mineral Density in Individuals over 60 Years of Age: A Systematic Review

    PubMed Central

    Shin, Hyehyung; Panton, Lynn B.; Dutton, Gareth R.; Ilich, Jasminka Z.

    2011-01-01

    The purpose of this review was to examine the relationship between physical performance and body composition measurements, including fat/muscle mass and bone mineral density (BMD) in individuals ≥60 years of age. Various measurements used to assess body composition, BMD, and physical performance (PP) were discussed as well. Medline/PubMed, CINAHL, and SCIE were used to identify articles. After limiting the search for age and kind of physical performance measures, 33 articles were evaluated. Higher fat mass was associated with poorer physical performance while higher muscle mass was a predictor of better physical performance, especially in the lower extremities. Additionally, evidence showed that higher muscle fat infiltration was a determinant of poorer physical performance. BMD was shown to be a good predictor of physical performance although the relationship was stronger in women than in men. Developing standardized methods for PP measurements could help in further investigation and conclusions of its relationship with body composition. PMID:21318048

  1. Is Presurgery and Early Postsurgery Performance Related to Speech and Language Outcomes at 3 Years of Age for Children with Cleft Palate?

    ERIC Educational Resources Information Center

    Chapman, Kathy

    2004-01-01

    This study examined the relationship between presurgery speech measures and speech and language performance at 39 months as well as the relationship between early postsurgery speech measures and speech and language performance at 39 months of age. Fifteen children with cleft lip and palate participated in the study. Spontaneous speech samples were…

  2. Inactivation of Pde8b enhances memory, motor performance, and protects against age-induced motor coordination decay

    PubMed Central

    Tsai, Li-Chun Lisa; Chan, Guy Chiu-Kai; Nangle, Shannon N.; Shimizu-Albergine, Masami; Jones, Graham; Storm, Daniel R.; Beavo, Joseph A.; Zweifel, Larry S.

    2012-01-01

    Phosphodiesterases (PDEs) are critical regulatory enzymes in cyclic nucleotide signaling. PDEs have diverse expression patterns within the central nervous system (CNS), show differing affinities for cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), and regulate a vast array of behaviors. Here, we investigated the expression profile of the PDE8 gene family members Pde8a and Pde8b in the mouse brain. We find that Pde8a expression is largely absent in the CNS; by contrast, Pde8b is expressed in select regions of the hippocampus, ventral striatum, and cerebellum. Behavioral analysis of mice with Pde8b gene inactivation (PDE8B KO) demonstrate an enhancement in contextual fear, spatial memory, performance in an appetitive instrumental conditioning task, motor-coordination, and have an attenuation of age-induced motor coordination decline. In addition to improvements observed in select behaviors, we find basal anxiety levels to be increased in PDE8B KO mice. These findings indicate that selective antagonism of PDE8B may be an attractive target for enhancement of cognitive and motor functions; however, possible alterations in affective state will need to be weighed against potential therapeutic value. PMID:22925203

  3. Association between executive function and physical performance in older Korean adults: findings from the Korean Longitudinal Study on Health and Aging (KLoSHA).

    PubMed

    Huh, Yoonseok; Yang, Eun Joo; Lee, Seung Ah; Lim, Jae-Young; Kim, Ki Woong; Paik, Nam-Jong

    2011-01-01

    Reduced executive function and physical performance are common age-related conditions. This study evaluated the associations between executive function and physical performance in a representative sample of older adults. Cross-sectional data were analyzed from a population-based sample of 629 men and women aged 65 or older and living in one typical city in Korea. Specific aspects of executive function were assessed using the trail making test, digit span test, and lexical fluency test to measure set shifting, working memory and cognitive flexibility functions. Physical performance was measured using performance-oriented mobility assessment (POMA) scores and isokinetic muscle strength. Subjects' self-efficacy was also assessed using the activities-specific balance confidence (ABC) scale. Results of the lexical fluency test were associated with POMA scores and muscle strength, independent of age, gender, education, comorbidity, physical activity status, depression, and global cognition, suggesting that reduced cognitive flexibility is associated with reduced physical performance and muscle strength. Self-efficacy was also independently associated with physical performance and muscle strength. Clinicians need to consider the association between executive function and physical performance when working to improve physical functioning in an aged population. PMID:21075462

  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. PMID:26499818

  5. 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...

  6. Associations of fatigue from mid to late life with physical performance and strength in early old age: Results from a British prospective cohort study

    PubMed Central

    Mänty, Minna; Kuh, Diana; Cooper, Rachel

    2015-01-01

    OBJECTIVE To examine associations of fatigue in mid and later life with physical performance and strength in early old age. METHODS Data on approximately 1800 men and women from the UK Medical Research Council National Survey of Health and Development with data on fatigue at ages 43 and 60-64 years were used. Fatigue was defined as perceived tiredness and was assessed prospectively at ages 43 and 60-64. At both ages, participants were categorized as having no, occasional or frequent fatigue. Physical performance and strength were measured at age 60-64 using four objective measures: grip strength, standing balance, chair rising, and timed get-up-and-go (TUG) tests. RESULTS There were associations between reports of frequent fatigue at both ages and poorer grip strength, chair rise and TUG performance at 60-64 years. Furthermore, individuals reporting frequent fatigue at both ages had weaker grip strength (β -4.09 kg, 95% CI -6.71, -1.48), and slower chair rise (β -4.65 rep./min, 95% CI -6.65, -2.64) and TUG (β -4.22 cm/s, 95% CI -12.16, -2.28) speeds when compared to those who reported no fatigue at both time points. These associations were robust and were maintained after adjustment for a range of covariates including physical activity and health status. CONCLUSIONS Reports of frequent fatigue were associated with poorer physical performance in early old age, especially if sustained from mid to later life. These findings indicate that it is not just fatigue but fatigue sustained across adulthood that has implications for later life functioning. PMID:26176776

  7. An age-related shift of resting-state functional connectivity of the subthalamic nucleus: a potential mechanism for compensating motor performance decline in older adults

    PubMed Central

    Mathys, Christian; Hoffstaedter, Felix; Caspers, Julian; Caspers, Svenja; Südmeyer, Martin; Grefkes, Christian; Eickhoff, Simon B.; Langner, Robert

    2014-01-01

    Healthy aging is associated with decline in basic motor functioning and higher motor control. Here, we investigated age-related differences in the brain-wide functional connectivity (FC) pattern of the subthalamic nucleus (STN), which plays an important role in motor response control. As earlier studies revealed functional coupling between STN and basal ganglia, which both are known to influence the conservativeness of motor responses on a superordinate level, we tested the hypothesis that STN FC with the striatum becomes dysbalanced with age. To this end, we performed a seed-based resting-state analysis of fMRI data from 361 healthy adults (mean age: 41.8, age range: 18–85) using bilateral STN as the seed region of interest. Age was included as a covariate to identify regions showing age-related changes of FC with the STN seed. The analysis revealed positive FC of the STN with several previously described subcortical and cortical regions like the anterior cingulate and sensorimotor cortex, as well as not-yet reported regions including central and posterior insula. With increasing age, we observed reduced positive FC with caudate nucleus, thalamus, and insula as well as increased positive FC with sensorimotor cortex and putamen. Furthermore, an age-related reduction of negative FC was found with precuneus and posterior cingulate cortex. We suggest that this reduced de-coupling of brain areas involved in self-relevant but motor-unrelated cognitive processing (i.e. precuneus and posterior cingulate cortex) from the STN motor network may represent a potential mechanism behind the age-dependent decline in motor performance. At the same time, older adults appear to compensate for this decline by releasing superordinate motor control areas, in particular caudate nucleus and insula, from STN interference while increasing STN-mediated response control over lower level motor areas like sensorimotor cortex and putamen. PMID:25100995

  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

    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. 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

  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. 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…

  13. 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…

  14. Reference Values and Age and Sex Differences in Physical Performance Measures for Community-Dwelling Older Japanese: A Pooled Analysis of Six Cohort Studies

    PubMed Central

    Seino, Satoshi; Shinkai, Shoji; Fujiwara, Yoshinori; Obuchi, Shuichi; Yoshida, Hideyo; Hirano, Hirohiko; Kim, Hun Kyung; Ishizaki, Tatsuro; Takahashi, Ryutaro

    2014-01-01

    Objectives To determine age- and sex-specific reference values for six physical performance measures, i.e. hand-grip strength, one-legged stance, and gait speed and step length at both usual and maximum paces, and to investigate age and sex differences in these measures among community-dwelling older Japanese adults. Methods We conducted a pooled analysis of data from six cohort studies collected between 2002 and 2011 as part of the Tokyo Metropolitan Institute of Gerontology-Longitudinal Interdisciplinary Study on Aging. The pooled analysis included cross-sectional data from 4683 nondisabled, community-dwelling adults aged 65 years or older (2168 men, 2515 women; mean age: 74.0 years in men and 73.9 years in women). Results Unweighted simple mean (standard deviation) hand-grip strength, one-legged stance, usual gait speed, usual gait step length, maximum gait speed, and maximum gait step length were 31.7 (6.7) kg, 39.3 (23.0) s, 1.29 (0.25) m/s, 67.7 (10.0) cm, 1.94 (0.38) m/s, and 82.3 (11.6) cm, respectively, in men and 20.4 (5.0) kg, 36.8 (23.4) s, 1.25 (0.27) m/s, 60.8 (10.0) cm, 1.73 (0.36) m/s, and 69.7 (10.8) cm, respectively, in women. All physical performance measures showed significant decreasing trends with advancing age in both sexes (all P<0.001 for trend). We also constructed age- and sex-specific appraisal standards according to quintiles. With increasing age, the sex difference in hand-grip strength decreased significantly (P<0.001 for age and sex interaction). In contrast, sex differences significantly increased in all other measures (all P<0.05 for interactions) except step length at maximum pace. Conclusion Our pooled analysis yielded inclusive age- and sex-specific reference values and appraisal standards for major physical performance measures in nondisabled, community-dwelling, older Japanese adults. The characteristics of age-related decline in physical performance measures differed between sexes. PMID:24923425

  15. The effects of rivastigmine plus selegiline on brain acetylcholinesterase, (Na+, K+)-, Mg2+-ATPase activities, antioxidant status, and learning performance of aged rats

    PubMed Central

    Carageorgiou, Haris; Sideris, Antonios C; Messari, Ioanna; Liakou, Chrissoula I; Tsakiris, Stylianos

    2008-01-01

    We investigated the effects of rivastigmine (a cholinesterase inhibitor) and selegiline ((-)deprenyl, an irreversible inhibitor of monoamineoxidase-B), alone and in combination, on brain acetylcholinesterase (AChE), (Na+, K+)-, Mg2+-ATPase activities, total antioxidant status (TAS), and learning performance, after long-term drug administration in aged male rats. The possible relationship between the biochemical and behavioral parameters was evaluated. Methods Aged rats were treated (for 36 days) with rivastigmine (0.3 mg/kg rat/day ip), selegiline (0.25 mg/kg rat/day im), rivastigmine plus selegiline in the same doses and way of administration as separately. Aged and adult control groups received NaCl 0.9% 0.5 ml ip. Results TAS was lower in aged than in adult rats, rivastigmine alone does not affect TAS, decreases AChE activity, increases (Na+, K+)-ATPase and Mg2+-ATPase activity of aged rat brain and improves cognitive performance. Selegiline alone decreases free radical production and increases AChE activity and (Na+, K+)-ATPase activity, improving cognitive performance as well. In the combination: rivastigmine seems to cancel selegiline action on TAS and AChE activity, while it has additive effect on (Na+, K+)-ATPase activity. In the case of Mg2+-ATPase selegiline appears to attenuate rivastigmine activity. No statistically significant difference was observed in the cognitive performance. Conclusion Reduced TAS, AChE activity and learning performance was observed in old rats. Both rivastigmine and selesiline alone improved performance, although they influenced the biochemical parameters in a different way. The combination of the two drugs did not affect learning performance. PMID:19043511

  16. Physical Activity Over the Life Course and its Association with Cognitive Performance and Impairment in Old Age

    PubMed Central

    Middleton, Laura E; Barnes, Deborah E; Lui, Li-Yung; Yaffe, Kristine

    2012-01-01

    Objective To determine how physical activity at various ages over the life course is associated with cognitive impairment in late life. Design Cross-sectional study Setting Four US sites. Participants We administered a modified Mini-Mental State Examination (mMMSE) to 9344 women ≥65 years (mean 71.6 years) who self-reported teenage, age 30, age 50, and late life physical activity. Measurements We used logistic regressions to determine the association between physical activity status at each age and likelihood of cognitive impairment (mMMSE score >1.5SD below the mean, mMMSE≤22). Models were adjusted for age, education, marital status, diabetes, hypertension, depressive symptoms, smoking, and body mass index. Results Women who reported being physically active had lower prevalence of cognitive impairment in late life compared to women who were inactive at each time (teenage: 8.5% vs. 16.7%; adjusted Odds Ratio (95% Confidence Interval): 0.65 (0.53–0.80); age 30: 8.9% vs. 12.0%; 0.80 (0.67–0.96); age 50: 8.5% vs. 13.1%; 0.71 (0.59–0.85); old age: 8.2% vs. 15.9%; 0.74 (0.61–0.91)). When the four times were analyzed together, teenage physical activity was most strongly associated with lower odds of late-life cognitive impairment (OR=0.73 (0.58–0.92)). However, women who were physically inactive at teenage and became active in later life had lower risk than those who remained inactive. Conclusions Women who reported being physically active at any point over the life course, and especially at teenage, have lower likelihood of cognitive impairment in late life. Interventions should promote physical activity early in life and throughout the life course. PMID:20609030

  17. 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

  18. Performance of the Osteoporosis Self-Assessment Tool for Asians (OSTA) in Screening Osteoporosis Among Middle-Aged and Old Women in the Chengdu Region of China.

    PubMed

    Huang, Ji-Yuan; Song, Wen-Zhong; Zeng, Hui-Rong; Huang, Mei; Wen, Qun-Fang

    2015-01-01

    The purpose of this study was to assess the performance of an osteoporosis self-assessment tool for Asians (OSTA) for screening middle-aged and old healthy women in the Chengdu region of China. OSTA scores were used to evaluate the effect of age on the development of osteoporosis. A total of 15,752 healthy women older than 40 yr, who reside in the Chengdu region, were assigned to 9 age groups divided by 5-yr intervals. Bone mineral density of the lumbar vertebrae, L1-L4, and the left hip was measured with a GE Lunar Prodigy advance dual-energy X-ray absorptiometry system (GE Healthcare, Cincinnati, OH). All subjects were classified into 3 categories according to OSTA cutoff values. The OSTA values used to define the categories were ≥-1, >-4 and <-1, and ≤-4. The accuracy of the OSTA index was compared with T-scores measured by dual-energy X-ray absorptiometry at various skeletal sites. All statistical analyses were performed using SPSS, version 17.0 (SPSS, Inc., Chicago, IL). The detection rate of osteoporosis and osteopenia at the lumbar vertebrae and the femur was found to increase with age. Furthermore, the sensitivity of OSTA value for detection of osteoporosis also gradually enhanced with subject age. In contrast, the specificity gradually decreased with age. The sensitivity and negative predictive value of the OSTA index for detecting osteoporosis gradually increased with higher OSTA cutoff values, and the specificity and positive predictive value appeared to gradually decline. It was concluded that the OSTA is a useful screening tool to detect osteoporosis in middle-aged and old women in the Chengdu region of China. Furthermore, specific OSTA cutoff values should be selected for screening individuals who belong to different age groups. PMID:25833193

  19. 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

  20. Job Stress, Stress Related to Performance-Based Accreditation, Locus of Control, Age, and Gender As Related to Job Satisfaction and Burnout in Teachers and Principals.

    ERIC Educational Resources Information Center

    Hipps, Elizabeth Smith; Halpin, Glennelle

    The purpose of the study described here was to: (1) determine the amount of variance in burnout and job satisfaction in public school teachers and principals which could be accounted for by stress related to the state's performance-based accreditation standards; (2) examine the relationship between stress related to state standards and the age and…

  1. The effect of active immunization against vasoactive intestinal peptide (VIP) and inhibin on reproductive performance of aging White Leghorn roosters.

    PubMed

    Avital-Cohen, N; Heiblum, R; Argov, N; Rosenstrauch, A; Chaiseha, Y; Mobarkey, N; Rozenboim, I

    2012-01-01

    Decreasing fertility in aging domestic roosters is a well-known phenomenon. Aging is manifested by a decrease in plasma testosterone level, testis function, and spermatogenesis, resulting in a low level of fertility. The roles of vasoactive intestinal peptide (VIP) and testicular inhibin in this aging process are not clear. The effects of active immunization against VIP, inhibin, or the combination of both hormones on the reproduction of aging White Leghorn (WL) roosters were assayed. In experiment 1a, 60 White Leghorn roosters (67 wk of age) were divided into 4 groups (n = 15/group). The first group was actively immunized against VIP, the second against inhibin, the third against VIP and inhibin, and the fourth served as a control. Active immunization against VIP decreased semen quality parameters, plasma steroid levels, and gene expression of gonadotropin-releasing hormone-I (GnRH-I), follicle-stimulating hormone (FSH), luteinizing hormone (LH), LH receptor, VIP, and prolactin (Prl). Immunization against inhibin increased some of the semen quality parameters and FSH mRNA gene expression but decreased inhibin gene expression. In experiment 1b, at 94 wk of age, we took the actively immunized against VIP group and the control group and divided them into 2 subgroups (n = 7 or 8): the first group was injected with 1 mg of ovine Prl (oPrl) daily for 7 d, and the second group served as a control. Administration of oPrl to previously VIP-immunized birds significantly elevated semen quality parameters. We suggest that VIP, Prl, and inhibin have an important effect on the reproductive axis in aging roosters. Active immunization against VIP-depressed reproductive activity and Prl administration restored their reproduction, indicating that both VIP and Prl are essential for reproduction in aging roosters. Immunization against inhibin improved FSH mRNA gene expression, suggesting a negative role of inhibin on FSH secretion in aging roosters. Not all semen quality parameters

  2. Prediction of Drug Clearance in Premature and Mature Neonates, Infants, and Children ≤2 Years of Age: A Comparison of the Predictive Performance of 4 Allometric Models.

    PubMed

    Mahmood, Iftekhar

    2016-06-01

    The objective of this study was to evaluate the predictive performance of 4 allometric models to predict clearance in pediatric ages ranging from premature neonates to children ≤2 years of age. Four allometric models were used to predict clearances of 28 drugs in children from preterm neonates to 2 years of age (n = 564). The 4 models are (1) basal metabolic rate-dependent model; (2) age-dependent exponent model; (3) an allometric model based on kidney and liver weights as well as kidney and liver blood flow; and (4) an allometric model based on a fixed exponent of 0.75. The predictive performance of these models was evaluated by comparing the predicted clearance of the studied drugs with the observed clearance in an individual child. The results of the study indicated that the 3 new proposed models predicted the mean clearance of the drugs with reasonable accuracy (≤50% prediction error). On the other hand, the exponent of 0.75 produced substantial prediction error. Predicted individual clearance values were ≥50% in approximately 30% of the children by the proposed 3 methods and 73% by exponent 0.75. The 3 new proposed allometric models can predict mean clearances of drugs in children from premature neonates to ≤2 years of age with reasonable accuracy and are of practical value during pediatric drug development. PMID:26437918

  3. A randomized controlled comparison of NAL and DSL prescriptions for young children: Hearing-aid characteristics and performance outcomes at three years of age

    PubMed Central

    Ching, Teresa YC; Dillon, Harvey; Hou, Sanna; Zhang, Vicky; Day, Julia; Crowe, Kathryn; Marnane, Vivienne; Street, Laura; Burns, Lauren; Van Buynder, Patricia; Flynn, Christopher; Thomson, Jessica

    2013-01-01

    Objective To determine the influence of choice of prescription and other child-, family- and intervention-related factors on speech, language, and functional performance of hearing-impaired children by three years of age. Design and study sample A randomized controlled design was implemented as part of a population-based, longitudinal study on outcomes of children with hearing impairment (LOCHI) in Australia. Two hundred and eighteen children were randomly assigned to either the NAL or the DSL prescription for first fitting of hearing aids. Their performance outcomes were evaluated. Results Prescriptive targets were closely matched in children's hearing aids. There were not significant differences in children's language, speech production, or functional performance between prescriptions. Parents' ratings of children's device usage and loudness discomfort were not significantly different between prescription groups. Functional performance within the first year of fitting together with degree of hearing loss, presence of additional disabilities, and maternal education explained 44% of variation in language ability of children by three years of age. Conclusions There was no significant association between choice of hearing-aid prescription and variance in children's outcomes at three years of age. In contrast, additional disability, maternal educational level, and early functional performance were significant predictive factors of children's outcomes. PMID:22934930

  4. Structural Aging Program to evaluate continued performance of safety-related concrete structures in nuclear power plants

    SciTech Connect

    Naus, D.J.; Oland, C.B.; Ellingwood, B.R.

    1994-03-01

    This report discusses the Structural Aging (SAG) Program which is being conducted at the Oak Ridge National Laboratory (ORNL) for the United States Nuclear Regulatory commission (USNRC). The SAG Program is addressing the aging management of safety-related concrete structures in nuclear power plants for the purpose of providing improved technical bases for their continued service. The program is organized into three technical tasks: Materials Property Data Base, Structural Component Assessment/Repair Technologies, and Quantitative Methodology for continued Service Determinations. Objectives and a summary of recent accomplishments under each of these tasks are presented.

  5. 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…

  6. Sleep spindles and rapid eye movement sleep as predictors of next morning cognitive performance in healthy middle-aged and older participants.

    PubMed

    Lafortune, Marjolaine; Gagnon, Jean-François; Martin, Nicolas; Latreille, Véronique; Dubé, Jonathan; Bouchard, Maude; Bastien, Célyne; Carrier, Julie

    2014-04-01

    Spindles and slow waves are hallmarks of non-rapid eye movement sleep. Both these oscillations are markers of neuronal plasticity, and play a role in memory and cognition. Normal ageing is associated with spindle and slow wave decline and cognitive changes. The present study aimed to assess whether spindle and slow wave characteristics during a baseline night predict cognitive performance in healthy older adults the next morning. Specifically, we examined performance on tasks measuring selective and sustained visual attention, declarative verbal memory, working memory and verbal fluency. Fifty-eight healthy middle-aged and older adults (aged 50-91 years) without sleep disorders underwent baseline polysomnographic sleep recording followed by neuropsychological assessment the next morning. Spindles and slow waves were detected automatically on artefact-free non-rapid eye movement sleep electroencephalogram. All-night stage N2 spindle density (no./min) and mean frequency (Hz) and all-night non-rapid eye movement sleep slow wave density (no./min) and mean slope (μV/s) were analysed. Pearson's correlations were performed between spindles, slow waves, polysomnography and cognitive performance. Higher spindle density predicted better performance on verbal learning, visual attention and verbal fluency, whereas spindle frequency and slow wave density or slope predicted fewer cognitive performance variables. In addition, rapid eye movement sleep duration was associated with better verbal learning potential. These results suggest that spindle density is a marker of cognitive functioning in older adults and may reflect neuroanatomic integrity. Rapid eye movement sleep may be a marker of age-related changes in acetylcholine transmission, which plays a role in new information encoding. PMID:24245769

  7. Performance.

    PubMed

    Chambers, David W

    2006-01-01

    High performance is difficult to maintain because it is dynamic and not well understood. Based on a synthesis of many sources, a model is proposed where performance is a function of the balance between capacity and challenge. Too much challenge produces coping (or a crash); excess capacity results in boredom. Over time, peak performance drifts toward boredom. Performance can be managed by adjusting our level of ability, our effort, the opportunity to perform, and the challenge we agree to take on. Coping, substandard but acceptable performance, is common among professionals and its long-term side effects can be debilitating. A crash occurs when coping mechanisms fail. PMID:17020177

  8. 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

  9. 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…

  10. 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…

  11. 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…

  12. 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

  13. 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

  14. Do I turn left or right? Effects of sex, age, experience and exit route on maze test performance in sheep.

    PubMed

    Hunter, Damien S; Hazel, Susan J; Kind, Karen L; Liu, Hong; Marini, Danila; Owens, Julie A; Pitcher, Julia B; Gatford, Kathryn L

    2015-02-01

    Brain development and function are susceptible to perturbation by environmental factors. Sheep are increasingly being used as a neurodevelopmental model due to timing similarities with humans, but effects of age, experience and sex on cognition are not well characterised in this species. We therefore studied memory and reversal learning in sheep using a modified Y-maze at two ages: naive 18 weeks old (18N: 23 male, 17 female), experienced 40 week old sheep that had previously been tested at 18 weeks (40E: 22 male, 17 female), and naive 40 weeks old (40N: 4 male, 10 female). Younger naive animals (18N) required more trials and time to solve the first reversal task (task R1) than 40E (P=0.007 and P<0.001 respectively). Experience also improved outcomes, with 40N sheep requiring more time to solve tasks L (P=0.034) and R1 (P=0.002) than 40E. Increasing age (40N cf. 18N) decreased bleat frequency in tasks R1, M2 and R2 (each P<0.05). In 40N females, outcomes also differed by exit method in task R1, with those that exited via an indirect route taking less time to pass tasks R1 (P=0.009) and R2 (P=0.015) than those that used a direct route. Age plus experience improved learning outcomes, demonstrating knowledge retention for 22 weeks in this species, whilst age alone affected mostly behavioral responses. These results provide comparison data, and can be utilised to improve experimental design, for studies of neurodevelopment in the sheep. PMID:25449405

  15. Estimating Geriatric Mortality after Injury Using Age, Injury Severity, and Performance of a Transfusion: The Geriatric Trauma Outcome Score

    PubMed Central

    Zhao, Frank Z.; Wolf, Steven E.; Nakonezny, Paul A.; Minhajuddin, Abu; Rhodes, Ramona L.; Paulk, M. Elizabeth

    2015-01-01

    Abstract Background: A tool to determine the probability of mortality for severely injured geriatric patients is needed. Objective: We sought to create an easily calculated geriatric trauma prognostic score based on parameters available at the bedside to aid in mortality probability determination. Methods: All patients ≥65 years of age were identified from our Level I trauma center's registry between January 1, 2000 and December 31, 2013. Measurements included age, Injury Severity score (ISS), units of packed red blood cells (PRBCs) transfused in the first 24 hours, and patients' mortality status at the end of their index hospitalization. As a first step, a logistic regression model with maximum likelihood estimation and robust standard errors was used to estimate the odds of mortality from age, ISS, and PRBCs after dichotomizing PRBCs as yes/no. We then constructed a Geriatric Trauma Outcome (GTO) score that became the sole predictor in the re-specified logistic regression model. Results: The sample (n=3841) mean age was 76.5±8.1 years and the mean ISS was 12.4±9.8. In-hospital mortality was 10.8%, and 11.9% received a transfusion by 24 hours. Based on the logistic regression model, the equation with the highest discriminatory ability to estimate probability of mortality was GTO Score=age+(2.5×ISS)+22 (if given PRBCs). The area under the receiver operating characteristic curve (AUC) for this model was 0.82. Selected GTO scores and their related probability of dying were: 205=75%, 233=90%, 252=95%, 310=99%. The range of GTO scores was 67.5 (survivor) to 275.1 (died). Conclusion: The GTO model accurately estimates the probability of dying, and can be calculated at bedside by those possessing a working knowledge of ISS calculation. PMID:25974408

  16. 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. PMID:26173010

  17. 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

  18. 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 ...

  19. 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…

  20. 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

  1. 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

  2. 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

  3. 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

  4. Executive function is less sensitive to estradiol than spatial memory: performance on an analog of the card sorting test in ovariectomized aged rhesus monkeys.

    PubMed

    Lacreuse, A; Chhabra, R K; Hall, M J; Herndon, J G

    2004-09-30

    Functions supported by the frontal lobes are particularly sensitive to the detrimental effects of aging. Recent studies on postmenopausal women find that estrogen replacement therapy benefits performance on tasks dependent on the frontal lobes. To determine whether estrogen has a similar influence in a rhesus monkey model of menopause, we tested five aged, long-term ovariectomized rhesus monkeys in a modified version of the Wisconsin Card Sort test which had been adapted to the nonhuman primate. In this test, monkeys had to select 3-D objects based either on color (blue, red, yellow) or shape (block, tube, cup) and had to be able to switch their response as a function of reinforcement contingencies. The monkeys were treated with placebo and ethinyl estradiol (EE2, 450 ng/kg/day) in alternation with each successive test. Contrary to our hypothesis, estradiol treatment did not affect performance. Because previous studies in the same monkeys [Neurobiol. Aging 23 (2002) 589] had shown that EE2 improves performance on a spatial memory task dependent on the hippocampus, but not on another task dependent upon the frontal lobes (the delayed response), we conclude that executive processes may be less sensitive to the effects of estradiol than hippocampal-dependent tasks. PMID:15499681

  5. 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…

  6. 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.

  7. Influences of F-strain Mycoplasma gallisepticum vaccine on productive and reproductive performance of commercial parent broiler chicken breeders on a multi-age farm.

    PubMed

    Liu, J J; Ding, L; Wei, J Z; Li, Y

    2013-06-01

    The influences of F-strain Mycoplasma gallisepticum (FMG) vaccine inoculation during the pullet period on the subsequent productive and reproductive performance of parent broiler chicken breeders on a multi-age farm were evaluated. Three thousand breeders were randomly divided into 2 treatment groups that were either vaccinated with FMG (FMG-vaccinated group) or not vaccinated with FMG (FMG-free group). Body weight and egg production were determined through approximately 50 wk of age. Egg weight and feed conversion was determined at 26, 32, 35, 38, and 43 wk of age. Egg quality parameters, including eggshell strength, egg-specific gravity, egg shape index, blood-meat spots, Haugh unit score, eggshell thickness, yolk:albumen ratio, percentage yolk, albumen and eggshell weights, and percentage fertility, hatchability, and second-quality chicks were determined at 26, 32, and 43 wk of age. Air sacs were examined and lesions were scored at 20, 32, and 50 wk of age. The number of mature ovarian follicles, histologies of ovary, and lengths, and histologies of the infundibulum, magnum, isthmus, uterus, and vagina were determined. In the present study, an increase in egg production of broiler breeder hens in the FMG-vaccinated group during peak of lay was compared with the FMG-free group. Feed conversion of hens in the FMG-vaccinated group was significantly less at 32, 35, 38, and 43 wk of age. Eggs from hens in the FMG-vaccinated group had a significantly higher Haugh units score at 26 wk of age and had a significantly higher eggshell thickness and lower incidence of blood-meat spots at 32 wk. Hatching eggs from hens in the FMG-vaccinated group had a significantly higher hatchability. The mean lesion score of air-sac lesion of birds in the FMG-vaccinated group was significantly less than FMG-vaccinated group. Uteruses of hens in the FMG-vaccinated group had a significantly longer length compared with the FMG-free group at 32 wk of age. The results indicate that inoculation

  8. 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

  9. Clinical implications of daytime sleepiness for the academic performance of middle school-aged adolescents with attention deficit hyperactivity disorder.

    PubMed

    Langberg, Joshua M; Dvorsky, Melissa R; Marshall, Stephen; Evans, Steven W

    2013-10-01

    This study investigated the relative impact of total time slept per night and daytime sleepiness on the academic functioning of 100 middle school-aged youth (mean age = 11.9) with attention deficit hyperactivity disorder (ADHD). The primary goal of the study was to determine if total time slept per night and/or daytime sleepiness, as measured by youth self-report on the Pediatric Daytime Sleepiness Scale (PDSS), predicted academic functioning above and beyond symptoms of ADHD and relevant covariates, such as intelligence, achievement scores and parent education level. Self-reported daytime sleepiness but not self-reported total time slept per night was associated significantly with all academic outcomes. When examined in a hierarchical regression model, self-reported daytime sleepiness significantly predicted parent-rated homework problems and academic impairment and teacher-rated academic competence above and beyond symptoms of ADHD and relevant covariates, but did not predict grade point average or teacher-rated academic impairment. The implications of these findings for understanding more clearly the association between ADHD and sleep and the functional implications of this relationship are discussed. PMID:23509927

  10. Middle-aged children of Alzheimer parents, a pilot study: stable neurocognitive performance at 20-year follow-up.

    PubMed

    Jarvik, Lissy F; La Rue, Asenath; Gokhman, Izabella; Harrison, Tracy; Holt, Lori; Steh, Bill; Harker, Judith; Larson, Scott; Yaralian, Pauline; Matsuyama, Steven; Rasgon, Natalie; Geschwind, Daniel; Freimer, Nelson; Jimenez, Elvira; Schaeffer, Jeffrey

    2005-12-01

    The objective of this pilot study on a convenience sample of 25 offspring of Alzheimer patients (mean age 61.5 +/- 8.8 years; range, 50-82) was the early detection of neurocognitive decline. This preliminary report appears to be the first one dealing with 20-year follow-up of neurocognitive data of Alzheimer's disease (AD) children. Digit symbol (Wechsler Adult Intelligence Scale) was the only of 11 neurocognitive measures with a significant decline. And that decline between first and last testing (mean = 19.98 +/- 0.30 years) was on raw scores, not scaled scores. Neither parents' age at onset of AD nor autopsy confirmation or offspring APOE-e4 status influenced neurocognitive results. More robust data than currently available are needed to confirm the findings of this first pilot study and to determine both the trajectory of neurocognitive decline in AD and the risks of developing AD faced by children whose parent had the disease. PMID:16306237

  11. 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.

  12. 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

  13. Selective Brain-Targeted Antagonism of p38 MAPKα Reduces Hippocampal IL-1β Levels and Improves Morris Water Maze Performance in Aged Rats

    PubMed Central

    Alam, John J.

    2015-01-01

    Abstract Background: P38 mitogen activated protein kinase (MAPK) α modulates microglia-mediated inflammatory responses and a number of neuronal physiological processes. Objective: To evaluate pre-clinically the pharmacological effects in the brain of p38 MAPKα inhibition with a brain-penetrant specific chemical antagonist. Methods: VX-745, a blood-brain barrier penetrant, highly selective p38 MAPKα inhibitor, and clinical stage investigational drug, was utilized. Initially, a pilot study in 26-month-old Tg2576 mice was conducted. Subsequently, a definitive dose-response study was conducted in aged (20–22 months) rats with identified cognitive deficits; n = 15 per group: vehicle, 0.5, 1.5, and 4.5 mg/kg VX-745 by oral gavage twice daily for 3 weeks. Assessments in aged rats included IL-1β, PSD-95, TNFα protein levels in hippocampus; and Morris water maze (MWM) test for cognitive performance. Results: Drug effect could not be assessed in Tg2576 mice, as little inflammation was evident. In cognitively-impaired aged rats, VX-745 led to significantly improved performance in the MWM and significant reduction in hippocampal IL-1β protein levels, though the effects were dissociated as the MWM effect was evident at a lower dose level than that required to lower IL-1β. Drug concentration-effect relationships and predicted human doses were determined. Conclusions: Selective inhibition of p38 MAPKα with VX-745 in aged rats reduces hippocampal IL-1β levels and improves performance in the MWM. As the two effects occur at different dose levels, the behavioral effect appears to be via a mechanism that is independent of reducing cytokine production. The predicted human doses should minimize risks of systemic toxicity. PMID:26401942

  14. 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.

  15. 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 ...

  16. 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…

  17. Association of Physical Performance and Pain With Fear of Falling Among Community—Dwelling Japanese Women Aged 65 Years and Older

    PubMed Central

    Tomita, Yoshihito; Arima, Kazuhiko; Kanagae, Mitsuo; Okabe, Takuhiro; Mizukami, Satoshi; Nishimura, Takayuki; Abe, Yasuyo; Goto, Hisashi; Horiguchi, Itsuko; Aoyagi, Kiyoshi

    2015-01-01

    Abstract 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

  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. More on the performance of LiFePO 4 electrodes-The effect of synthesis route, solution composition, aging, and temperature

    NASA Astrophysics Data System (ADS)

    Koltypin, M.; Aurbach, D.; Nazar, L.; Ellis, B.

    Three types of olivine compounds were prepared by three different routes: sol-gel, solid-state, and hydrothermal syntheses, showing the expected structure and containing a small amount of carbon and iron phosphide for maintaining sufficient intrinsic electrical conductivity. These materials were tested in LiClO 4, and in dry and wet LiPF 6 solutions in mixtures of ethylene and dimethyl carbonate (EC-DMC, 1:1) at 30 and 60 °C. Iron dissolution from these materials, upon storage in the three solutions at these two temperatures, was measured by ICP. Aged electrodes were measured by XRD and SEM: the electrochemical performance of the three types of olivine compounds in the three solutions and at the two temperatures was measured by voltammetry and impedance spectroscopy. The behavior of pristine and aged electrodes was systematically compared. It was found that there is a strong correlation between the rate of iron dissolution and the performance of these systems in terms of high capacity, low capacity fading, and low and stable impedance upon aging. The material prepared by sol-gel synthesis demonstrated a low iron dissolution rate, even in a corrosive solution such as wet LiPF 6 solutions, and high performance, even in these solutions. When the solutions contain no acidic contaminants, all the compounds demonstrated negligible iron dissolution rates, even at 60 °C, and a good electrochemical performance. The electrochemical comparison described herein shows a pronounced impact of the solution composition on the electrodes' impedance, due to the unique surface chemistry developed in each solution.

  1. Body composition and exercise performance as determinants of blood rheology in middle-aged patients exhibiting the metabolic syndrome.

    PubMed

    Brun, Jean-Frédéric; Varlet-Marie, Emmanuelle; Fédou, Christine; Raynaud de Mauverger, Eric

    2011-01-01

    Aerobic capacity and performance are associated with increased blood fluidity, while sedentarity leads to decreased exercise performance, and blood hyperviscosity. We aimed at investigating the relationships among body composition, blood rheology and exercise performance in this situation. In 46 sedentary subjects (53.09 ± 1.79 yr old; BMI = 32,35 ± 0,80) attending our unit for an exercise prescription we performed an exercise test to assess aerobic capacity, together with blood lipid profile and blood viscosity (MT 90 viscometer, Myrenne erythroaggregometer). The maximal aerobic capacity VO2max was not correlated to blood rheology but its changes were negatively correlated to those of plasma viscosity (r = -0.679) and pre-training VO2max values were negatively correlated to the BMI (r = -0.45873; p = 0.00430) and fatness (waist circumference r = -0.53476; p = 0.00406). Hemorheological parameters were as expected correlated to blood lipids. The main determinant of the RBC rigidity index Tk was HDL-cholesterol (r = -0.70026; p = 0.00121). The main determinant of M1 is HDL-cholesterol (r = -0.5157; p = 0.0238). RBC aggregability "M" is negatively correlated to total cholesterol (r = -0.758932; p = 0.000105); HDL-cholesterol (r = -0.62232; p = 0.00444); LDL-cholesterol (r = -0.64486; p = 0.00386). Whole blood viscosity is correlated to triglycerides (r = 0.8569; p = 0.00000140) and negatively correlated to HDL-cholesterol (r = -0.5622; p = 0.0122). Waist circumference (an index of abdominal fatness) is correlated to blood viscosity (r = 0.597; p = 0.00888). The waist to hip ratio is correlated to Hct (r = 0.70075 p = 0.00120) and to blood viscosity (r = 0.8124334; p = 0.0000420). Fat-free mass is correlated to blood viscosity (r = 0.66528; p = 0.00137) and hematocrit (r = 0.64350; p = 0.00220). Hip circumference is negatively correlated to plasma viscosity (r = -0.5007; p = 0.0290). Therefore, this study confirms that hemorheological parameters are influenced by

  2. Variations in highway stormwater runoff quality and stormwater treatment performance in relation to the age of porous friction courses.

    PubMed

    Moores, Jonathan P; Pattinson, Peter E; Hyde, Christian R

    2013-09-01

    A program of highway runoff sampling was conducted at four sites in Auckland, New Zealand. Concentrations of suspended solids, particulate copper, and zinc were significantly lower in runoff from a highway paved with a 1-year-old porous friction course (PFC) than in runoff at the other sites. Differences in total metal concentrations were less marked, reflecting relatively high concentrations of dissolved copper and zinc in runoff from the 1-year-old PFC. Runoff quality at a highway site that had been paved with a PFC 6 years previously was similar to that discharged from two impermeable roads, indicating a reduction over time in the quality of runoff discharged from PFCs. Runoff from the highways paved with 1- and 6-year-old PFCs was treated by a grass swale and wet pond, respectively. Both treatments were effective, the former predominantly through the lowering of dissolved metal concentrations and the latter through the lowering of particulate metal concentrations. These results indicate that stormwater treatment can improve the quality of runoff discharged from PFCs, irrespective of their age, provided that treatment is targeted to the predominant contaminant phase present. PMID:24175407

  3. Orbitofrontal Cortex Volume in Area 11/13 Predicts Reward Devaluation, But Not Reversal Learning Performance, in Young and Aged Monkeys

    PubMed Central

    Burke, Sara N.; Thome, Alex; Plange, Kojo; Engle, James R.; Trouard, Theodore P.; Gothard, Katalin M.

    2014-01-01

    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. 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

  5. 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

  6. High specification starter diets improve the performance of low birth weight pigs to 10 weeks of age.

    PubMed

    Douglas, S L; Wellock, I; Edwards, S A; Kyriazakis, I

    2014-10-01

    Piglets born with low birth weights (LBiW) are likely to be lighter at weaning. Starter regimes tailored for pigs of average BW therefore may not be optimal for LBiW nursery performance. The objective was to determine if LBiW pigs benefit from a high specification starter regime and the provision of extra feed (additional allowance of last phase diet of the starter regime) in comparison to a standard commercial regime. Additionally, the effect of starter regime on performance of normal birth weight (NBiW) pigs at weaning was determined and compared to that of LBiW pigs. Finally, the cost effectiveness of the treatments was determined. The experiment was therefore an incomplete 2 × 2 × 2 factorial design, as the provision of extra feed was given only to LBiW pigs (n = 6 replicates per treatment; 5 pigs per replicate). Treatments comprised birth weight (LBiW or NBiW), starter regime (high specification [HS] or standard starter [SS]), and extra feed 3 quantity (yes [YF] or no [NF], for LBiW pigs only; feed 3 corresponded to the last phase diet of the starter regime). At weaning (d 28), pigs were randomly assigned within each birth weight category to treatment groups. Nutritional treatments were fed ad libitum on a kilogram/head basis for approximately 3 wk followed by a common weaner diet fed ad libitum until d 70. Starter regime (P = 0.019), feed 3 amount (P = 0.010), and their interaction (P = 0.029) had an effect on ADG of LBiW pigs from d 28 to 49, with pigs on HS followed by YF (HY) performing best. An improvement in feed conversion ratio (FCR) was noted between d 28 and 49 for pigs fed the additional feed 3 (P = 0.030); between d 49 and 70, the only residual effect seen was of starter regime (P = 0.017) on ADG. In contrast, there was no significant effect of starter regime from d 28 to 70 on ADG, ADFI, or FCR of NBiW pigs. By d 49 and 70, LBiW pigs on regime HY weighed the same as NBiW pigs (d 70 BW; 30.0 vs. 30.6 kg; P = 0.413), with similar growth rates from

  7. 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

  8. Improved motor and cognitive performance with sodium nitrite supplementation is related to small metabolite signatures: a pilot trial in middle-aged and older adults

    PubMed Central

    DeVan, Allison E.; Cruickshank-Quinn, Charmion; Reisdorph, Nichole; Bassett, Candace J.; Evans, Trent D.; Brooks, Forrest A.; Bryan, Nathan S.; Chonchol, Michel B.; Giordano, Tony; McQueen, Matthew B.; Seals, Douglas R.

    2015-01-01

    Advancing age is associated with reductions in nitric oxide bioavailability and changes in metabolic activity, which are implicated in declines in motor and cognitive function. In preclinical models, sodium nitrite supplementation (SN) increases plasma nitrite and improves motor function, whereas other nitric oxide-boosting agents improve cognitive function. This pilot study was designed to translate these findings to middle-aged and older (MA/O) humans to provide proof-of-concept support for larger trials. SN (10 weeks, 80 or 160 mg/day capsules, TheraVasc, Inc.) acutely and chronically increased plasma nitrite and improved performance on measures of motor and cognitive outcomes (all p<0.05 or better) in healthy MA/O adults (62 ± 7 years). Untargeted metabolomics analysis revealed that SN significantly altered 33 (160 mg/day) to 45 (80 mg/day) different metabolites, 13 of which were related to changes in functional outcomes; baseline concentrations of 99 different metabolites predicted functional improvements with SN. This pilot study provides the first evidence that SN improves aspects of motor and cognitive function in healthy MA/O adults, and that these improvements are associated with, and predicted by, the plasma metabolome. Our findings provide the necessary support for larger clinical trials on this promising pharmacological strategy for preserving physiological function with aging. PMID:26626856

  9. Improved motor and cognitive performance with sodium nitrite supplementation is related to small metabolite signatures: a pilot trial in middle-aged and older adults.

    PubMed

    Justice, Jamie N; Johnson, Lawrence C; DeVan, Allison E; Cruickshank-Quinn, Charmion; Reisdorph, Nichole; Bassett, Candace J; Evans, Trent D; Brooks, Forrest A; Bryan, Nathan S; Chonchol, Michel B; Giordano, Tony; McQueen, Matthew B; Seals, Douglas R

    2015-11-01

    Advancing age is associated with reductions in nitric oxide bioavailability and changes in metabolic activity, which are implicated in declines in motor and cognitive function. In preclinical models, sodium nitrite supplementation (SN) increases plasma nitrite and improves motor function, whereas other nitric oxide-boosting agents improve cognitive function. This pilot study was designed to translate these findings to middle-aged and older (MA/O) humans to provide proof-of-concept support for larger trials. SN (10 weeks, 80 to 160 mg/day capsules, TheraVasc, Inc.) acutely and chronically increased plasma nitrite and improved performance on measures of motor and cognitive outcomes (all p<0.05 or better) in healthy MA/O adults (62 ± 7 years). Untargeted metabolomics analysis revealed that SN significantly altered 33 (160 mg/day) to 45 (80 mg/day) different metabolites, 13 of which were related to changes in functional outcomes; baseline concentrations of 99 different metabolites predicted functional improvements with SN. This pilot study provides the first evidence that SN improves aspects of motor and cognitive function in healthy MA/O adults, and that these improvements are associated with, and predicted by, the plasma metabolome. Our findings provide the necessary support for larger clinical trials on this promising pharmacological strategy for preserving physiological function with aging. PMID:26626856

  10. 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

  11. 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

  12. Effects of Heat-oxidized Soy Protein Isolate on Growth Performance and Digestive Function of Broiler Chickens at Early Age.

    PubMed

    Chen, X; Chen, Y P; Wu, D W; Wen, C; Zhou, Y M

    2015-04-01

    This study was conducted to investigate effects of heat-oxidized soy protein isolate (HSPI) on growth performance, serum biochemical indices, apparent nutrient digestibility and digestive function of broiler chickens. A total of 320 1-day-old Arbor Acres chicks were randomly divided into 4 groups with 8 replicates of 10 birds, receiving diets containing soy protein isolate (SPI, control group) or the same amount of SPI heated in an oven at 100°C for 1, 4, or 8 h, for 21 days, respectively. The results indicated that compared with the control group, body weight gain and feed intake of birds fed diet containing SPI heated for 8 h were significantly lower (p<0.05). Serum urea nitrogen concentration was higher in the broilers fed diet containing SPI heated for 4 or 8 h at d 21 (p<0.05). In contrast, serum glucose content was decreased by HSPI substitution at d 21 (p<0.05). The relative pancreas weight in HSPI groups was higher than that in the control group at d 21 (p<0.05). Meanwhile, the opposite effect was observed for relative weight of anterior intestine and ileum in broilers fed a diet containing SPI heated for 8 h (p<0.05). Birds fed diets containing SPI heated for 4 or 8 h had a decreased lipase activity in anterior intestinal content at d 14 and 21 (p<0.05), respectively. In addition, the same effect was also noted in broilers given diets containing SPI heated for 1 h at d 21 (p<0.05). Similarly, amylase, protease and trypsin activity in anterior intestinal content were lower in broilers fed diets containing SPI heated for 8 h at d 21 (p<0.05). The apparent digestibility of dry matter (DM) from d 8 to 10 and DM, crude protein (CP), and ether extract from d 15 to 17 were lower in broilers fed diets containing SPI heated for 8 h (p<0.05). Besides, birds given diets containing SPI heated for 4 h also exhibited lower CP apparent digestibility from d 15 to 17 (p<0.05). It was concluded that HSPI inclusion can exert a negative influence on the growth performance of

  13. 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

  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. Resting state electroencephalographic correlates with red cell long-chain fatty acids, memory performance and age in adolescent boys with attention deficit hyperactivity disorder.

    PubMed

    Sumich, Alexander; Matsudaira, Toshiko; Gow, Rachel V; Ibrahimovic, Almira; Ghebremeskel, Kebreab; Crawford, Michael; Taylor, Eric

    2009-12-01

    Abnormal fatty acid status has been implicated in the aetiology of attention deficit hyperactivity disorder (ADHD). Delayed maturation in ADHD may result in raised frontal low frequency (theta) electroencephalographic activity (EEG) and a reduction in posterior high frequency (beta, alpha) activity. The current study used sequential linear regression to investigate the association between age, resting-state EEG and levels of long-chain polyunsaturated omega-3 and omega-6 fatty acids in red blood cells in 46 adolescent boys with ADHD symptoms. Docosahexaenoic acid (DHA) levels were positively associated with fast frequency activity: alpha during eyes-open and beta during eyes-closed conditions. Frontal theta activity during both eyes-open and eyes-closed conditions was inversely associated with age and positively associated with eicosapentaenoic acid (EPA) levels. Alpha activity correlated positively with performance on fluency for categories (semantic memory). Theta activity correlated inversely with performance on delayed (25 min) verbal memory (recall + recognition/2). No associations were observed between long-chain omega-6 and EEG measures. Results support differential associations for DHA and EPA with fast and slow EEG activity respectively. Results support EEG activity as an objective biomarker of neural function associated with long-chain omega-3 fatty acids in ADHD. PMID:19627997

  16. 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

  17. Effect of milk replacer program on calf performance and digestion of nutrients with age of the dairy calf.

    PubMed

    Chapman, C E; Erickson, P S; Quigley, J D; Hill, T M; Bateman, H G; Suarez-Mena, F X; Schlotterbeck, R L

    2016-04-01

    Calves fed large amounts of milk replacer (MR) gain more body weight preweaning than calves fed less-aggressive programs; however, postweaning growth may be reduced. Limited research suggests that less than optimal digestion of the postweaned diet due to large amounts of MR with reduced dry feed intake preweaning may contribute to growth impairment postweaning. Current research was conducted to compare growth and postweaning digestion in 3-d-old male Holstein calves fed various MR programs. The MR programs were a conventional [CON; 0.44kg of dry matter (DM) 21% crude protein (CP), 21% fat powder fed for 42d], moderate (MOD; 0.66kg of DM 27% CP, 17% fat powder fed for 42d), and aggressive program (AGG; up to 0.87kg of DM 27% CP, 17% fat powder fed for 49d). All calves were fed a 20% CP textured starter and water ad libitum for 56d. The trial used 96 calves (initially 41±1.9kg of body weight) received 5 wk apart in 2 groups of 48 calves. During d 51 to 56, fecal samples were collected from 5 calves per treatment randomly selected from calves in the first group. Selected nutrients and acid-insoluble ash (used as an internal flow marker) were analyzed in the starter and feces to estimate digestibility. Data were analyzed as a randomized complete block design with starting time of each group of calves as a block. Repeated measure analysis was performed on overall (0 to 56d) data. Means were separated with a protected least significant difference test. Pen was the experimental unit. Calves fed CON had the least average daily gain [CON=0.35, MOD=0.51, and AGG=0.55kg/d; standard error of the mean (SEM)=0.018], feed efficiency (CON=0.35, MOD=0.49, and AGG=0.48 gain/feed, SEM=0.016), and change in hip width (CON=3.3, MOD=4.1, and AGG=4.1cm, SEM=0.20) compared with calves fed other programs. Calves fed AGG had the greatest change in BCS and least starter intake compared with calves fed the other programs. Digestibility of organic matter was 79, 78, and 68% and neutral

  18. A Reanalysis of Cognitive-Functional Performance in Older Adults: Investigating the Interaction Between Normal Aging, Mild Cognitive Impairment, Mild Alzheimer's Disease Dementia, and Depression.

    PubMed

    de Paula, Jonas J; Bicalho, Maria A; Ávila, Rafaela T; Cintra, Marco T G; Diniz, Breno S; Romano-Silva, Marco A; Malloy-Diniz, Leandro F

    2015-01-01

    Depressive symptoms are associated with cognitive-functional impairment in normal aging older adults (NA). However, less is known about this effect on people with mild Cognitive Impairment (MCI) and mild Alzheimer's disease dementia (AD). We investigated this relationship along with the NA-MCI-AD continuum by reanalyzing a previously published dataset. Participants (N = 274) underwent comprehensive neuropsychological assessment including measures of Executive Function, Language/Semantic Memory, Episodic Memory, Visuospatial Abilities, Activities of Daily Living (ADL), and the Geriatric Depression Scale. MANOVA, logistic regression and chi-square tests were performed to assess the association between depression and cognitive-functional performance in each group. In the NA group, depressed participants had a lower performance compared to non-depressed participants in all cognitive and functional domains. However, the same pattern was not observed in the MCI group or in AD. The results suggest a progressive loss of association between depression and worse cognitive-functional performance along the NA-MCI-AD continuum. PMID:26858666

  19. 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

  20. 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

  1. Effects of dietary L-carnitine and coenzyme Q10 at different supplemental ages on growth performance and some immune response in ascites-susceptible broilers.

    PubMed

    Geng, Ailian; Li, Baoming; Guo, Yuming

    2007-02-01

    Effects of dietary L-carnitine and coenzyme Q10 (CoQ10) at different supplemental ages on performance and some immune response were investigated in ascites-susceptible broilers. A 3 x 2 x 2 factorial design was used consisting of L-carnitine supplementation (0, 75, and 100 mg/kg), CoQ10 supplementation (0 and 40 mg/kg) and different supplemental ages (from day 1 on and from day 10 on). A total of 480 one-day-old Arbor Acre male broiler chicks were randomly allocated to 12 groups, every group had five replicates, each with eight birds. The birds were fed a corn-soybean based diet for six weeks. From day 10-21, all the birds were exposed to a low ambient temperature (12-15 degrees C) to increase the susceptibility to ascites. No significant effects were observed on growth performance by L-carnitine, CoQ10 supplementation, and different supplemental ages. Packed cell volume was significantly decreased by L-carnitine supplementation alone, and ascites heart index and ascites mortality were decreased by L-carnitine, CoQ10 supplementation alone, and L-carnitine + CoQ10 supplementation together (p < 0.05). Heart index of broilers was significantly improved by L-carnitine, CoQ10 supplementation alone during 0-3 week. Serum IgG content was improved by L-carnitine supplementation alone (p < 0.05), but lysozyme activity was increased by L-carnitine + CoQ10 supplementation together (p < 0.05). A significant L-carnitine by supplemental age interaction was observed in lysozyme activity. L-carnitine supplementation alone had no effects on the peripheral blood lymphocyte (PBL) proliferation in response to concanavalin A (ConA) and lipopolysaccharide, but supplemental CoQ10 alone and L-carnitine+ CoQ10 together decreased the PBL proliferation in response to ConA (p < 0.05). The present study suggested that L-carnitine + CoQ10 supplementation together had positive effects on some immune response of ascites-susceptible broilers, which might benefit for the reduction of broilers

  2. 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. PMID:26112040

  3. Age differences in high frequency phasic heart rate variability and performance response to increased executive function load in three executive function tasks

    PubMed Central

    Byrd, Dana L.; Reuther, Erin T.; McNamara, Joseph P. H.; DeLucca, Teri L.; Berg, William K.

    2015-01-01

    The current study examines similarity or disparity of a frontally mediated physiological response of mental effort among multiple executive functioning tasks between children and adults. Task performance and phasic heart rate variability (HRV) were recorded in children (6 to 10 years old) and adults in an examination of age differences in executive functioning skills during periods of increased demand. Executive load levels were varied by increasing the difficulty levels of three executive functioning tasks: inhibition (IN), working memory (WM), and planning/problem solving (PL). Behavioral performance decreased in all tasks with increased executive demand in both children and adults. Adults’ phasic high frequency HRV was suppressed during the management of increased IN and WM load. Children’s phasic HRV was suppressed during the management of moderate WM load. HRV was not suppressed during either children’s or adults’ increasing load during the PL task. High frequency phasic HRV may be most sensitive to executive function tasks that have a time-response pressure, and simply requiring performance on a self-paced task requiring frontal lobe activation may not be enough to generate HRV responsitivity to increasing demand. PMID:25798113

  4. Diel flight pattern and flight performance of Cactoblastis cactorum (Lepidoptera: Pyralidae) measured on a flight mill: influence of age, gender, mating status, and body size.

    PubMed

    Sarvary, Mark A; Bloem, Kenneth A; Bloem, Stephanie; Carpenter, James E; Hight, Stephen D; Dorn, Silvia

    2008-04-01

    Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae) is an invasive herbivore that poses a serious risk to Opuntia cacti in North America. Knowledge of the flight behavior of the cactus moth is crucial for a better understanding of natural dispersal, and for both monitoring and control. We used computer-linked flight mills to investigate diel flight activity and flight performance in relation to gender, age, mating status, and body size. Maximal flight activity for both mated and unmated moths occurred during twilight, whereas flight activity was low during photophase. The total distance flown and the number of initiated flights within a diel cycle were higher in both unmated and mated females than in males, but the longest single flight was similar in both genders. These findings suggest that pheromone trap captures of males likely indicate the simultaneous presence of females and that mated females might even be in areas where males are not detected yet. Flight performance heterogeneity was large, with a small portion of the population (both males and females) performing long unbroken flights, whereas the majority made short flights. Females had higher pupal and adult body size and shorter longevity than males. A few individuals, particularly young mated females, flying long distances may be important for active spread of a population and the colonization of new habitats. Implications of this study in the control of the cactus moth by using the sterile insect technique are discussed. PMID:18459394

  5. Assessment of growth performance, immune responses, serum metabolites, and prevalence of leg weakness in broiler chicks submitted to early-age water restriction.

    PubMed

    Toghyani, Mehdi; Toghyani, Majid; Shahryar, Habib Aghdam; Zamanizad, Mehdi

    2011-08-01

    The objective of this study was to evaluate the effects of two methods of early-age water restriction on performance, some immune responses, serum metabolites, and prevalence of leg weakness in broiler chicks. One-hundred-eighty-seven-day-old chicks (Ross 308) were allocated to three treatments with four replicates based on a completely randomized design. Treatments included the control group, where birds had free access to water, and water-restricted groups, where access to water was limited to three 2-h periods (WRT1) or a 12-h period (WRT2) per day from days 7 to 17. Chicks in the control group were significantly heavier (P < 0.05) at 17 and 46 days of age compared to the restricted birds. In the WRT2 group, feed intake decreased significantly over the 17- to 28-day period while feed conversion ratio was poorer during water restriction (P < 0.05). Antibody titers against Newcastle and SRBC were higher (P < 0.05) for chicks with ad libitum access to water. Birds in the restricted groups exhibited a higher heterophil to lymphocyte ratio compared to the control group (P < 0.05). The treatments had no significant impact on serum metabolites including protein, triglyceride, total cholesterol, high-density lipoprotein and low-density lipoprotein cholesterols, calcium, and phosphorus concentrations. Walking ability, tibial dyschondroplasia, foot pad, hock burn, and valgus/varus angulation were not significantly influenced by water restriction. In conclusion, the current results indicate that early-age water restriction negatively influenced productive traits and immunological responses of broiler chicks and failed to have any favorable impacts on leg health. PMID:21455695

  6. A Method for Investigating Age-related Differences in the Functional Connectivity of Cognitive Control Networks Associated with Dimensional Change Card Sort Performance

    PubMed Central

    DeBenedictis, Bianca; Morton, J. Bruce

    2014-01-01

    The ability to adjust behavior to sudden changes in the environment develops gradually in childhood and adolescence. For example, in the Dimensional Change Card Sort task, participants switch from sorting cards one way, such as shape, to sorting them a different way, such as color. Adjusting behavior in this way exacts a small performance cost, or switch cost, such that responses are typically slower and more error-prone on switch trials in which the sorting rule changes as compared to repeat trials in which the sorting rule remains the same. The ability to flexibly adjust behavior is often said to develop gradually, in part because behavioral costs such as switch costs typically decrease with increasing age. Why aspects of higher-order cognition, such as behavioral flexibility, develop so gradually remains an open question. One hypothesis is that these changes occur in association with functional changes in broad-scale cognitive control networks. On this view, complex mental operations, such as switching, involve rapid interactions between several distributed brain regions, including those that update and maintain task rules, re-orient attention, and select behaviors. With development, functional connections between these regions strengthen, leading to faster and more efficient switching operations. The current video describes a method of testing this hypothesis through the collection and multivariate analysis of fMRI data from participants of different ages. PMID:24837515

  7. 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.

  8. Quantitative profiling of bile acids in rat bile using ultrahigh-performance liquid chromatography-orbitrap mass spectrometry: Alteration of the bile acid composition with aging.

    PubMed

    Lee, Gakyung; Lee, Hyunbeom; Hong, Jongki; Lee, Soo Hyun; Jung, Byung Hwa

    2016-09-15

    Bile acids (BAs) play important roles in physiological functions, including the homeostasis of cholesterol and lipids and as ligands for G protein-coupled receptors (GPCRs). With the increasing importance of BAs, analytical methods for their quantification and screening have been developed. However, due to the diverse range and variety of BAs with different activation potency, a simple, effective, and sensitive method is required to screen BAs for accurate quantification and identification. This paper presents an application of ultrahigh-performance liquid chromatography-orbitrap mass spectrometry (UHPLC-LTQ-Orbitrap MS) for profiling BAs in bile. Using this method, along with the accurate quantification of 19 targeted BAs, 22 unknown BAs were detected and characterized by their fragmentation patterns. The method is beneficial for screening most of the BAs (quantitatively and qualitatively) in rat bile with simple preparation in a single run. The sample dilution ranges of each BA were optimized depending on the concentration of BAs in the bile to obtain good peak separation and accurate data. The method validation was performed successfully using charcoal-treated bile and the intra and inter-day coefficients of variation were less than 20% for all BAs while the recovery were above 88.5% except for the lithocholic acid. The method was applied to profile the age-dependent changes in the contents of rat BAs. Through statistical analysis, we found that as the rats aged, unconjugated BAs and glycine-conjugated BAs decreased or were unaffected, while taurine-conjugated BAs were increased in general. Among the unknown BAs, 5 of the taurine-conjugated BAs increased, while a glycine-conjugated BA decreased, in agreement with the trends of the targeted BAs. PMID:27450898

  9. Effect of milk feed source, frequency of feeding and age at turnout on calf performance, live-weight at mating and 1st lactation milk production

    PubMed Central

    2012-01-01

    Female calves (n = 108) were assigned to 6 cold milk feeding treatments in two experiments for a 70-day period. Live-weight (LW) was measured weekly, with an additional LW taken at day 410 and post-calving for animals in experiment 1. In Experiment 1, the effect of feeding frequency and age of turnout to pasture on calf performance and 1st lactation milk yields were evaluated. The whole milk (WM) feeding treatments applied were (i) once daily feeding (OD), (ii) twice daily feeding (TD), (iii) OD feeding, outdoors at 38 days (ODO). In Experiment 2, the effects of feeding milk replacer (MR) as opposed to WM and age of turnout to pasture on calf performance were evaluated. The treatments applied were (i) OD feeding with WM (OD), (ii) OD feeding with milk replacer (MR) (ODMR), (iii) OD feeding with MR, outdoors at 38 days (ODMRO). Experiment 1: There were no differences (P > 0.05) in LW or average daily gain between TD and OD calves at day 80 or 410. ODO calves had lower LW at day 80 as compared to OD or TD (P < 0.001). Calf LW at day 80 was 86, 89 and 85 kg and at day 410 was 304, 309 and 316 kg for OD, TD and ODO, respectively. Milk feeding frequency or time of calf turnout had no effect on LW post calving, milk composition or 1st lactation milk yields. Experiment 2: Total LW at day 80 was higher (P < 0.05) for ODMR compared to OD or ODMRO calves. Calf LW was 87, 95, and 88 kg for OD, ODMR and ODMRO, respectively. However, LW at day 410 did not differ between treatments. This study showed that while some differences were observed in calf LW at day 80, these differences had no effect on LW at day 410 or 1st lactation milk yield. It can be concluded that calves can be successfully reared when fed OD with WM or MR, indoors and when turned out to pasture at 38 days of age. PMID:23078871

  10. Effects of percentage Brahman and Angus breeding, age-season of feeding and slaughter end point on feedlot performance and carcass characteristics.

    PubMed

    Huffman, R D; Williams, S E; Hargrove, D D; Johnson, D D; Marshall, T T

    1990-08-01

    Steers (n = 165) of known percentage Brahman (B) and Angus (A) breeding were used to study effects of breed group (A, 3/4A:1/4B, 1/2A:1/2B, 1/4A:3/4B), age-season of feeding (calves fed during the cool season vs yearlings fed during the warm season) and slaughter end point (less than .90, 1.0 to 1.15, 1.27 to 1.40, greater than or equal to 1.5 cm of adjusted fat over the ribeye) on feedlot performance and carcass characteristics. The 1/2B and 3/4B steers had heavier (P less than .05) initial and final feedlot weights than the A and 1/4B steers and higher (P less than .05) unshrunk ADG than the A steers did. Breed types did not differ for feed efficiency. Yearling steers fed in the warm season had higher (P less than .05) unshrunk ADG than calves fed in the cool season, but ADG calculated on an empty-rumen basis did not differ between the two age-seasons of feeding. Calves fed in the cool season were more efficient (P less than .05) than yearlings fed in the warm season when efficiency was expressed on an empty-rumen basis; however, on a live weight basis there was no difference in feed efficiency. No breed group by age-season of feeding interactions on performance were detected. Slaughter end point did not significantly affect feed efficiency on an empty-rumen basis. The 1/2B and 3/4B steers had smaller ribeye areas (REA) per 100 kg hot carcass and lower marbling scores than the 1/4B and A steers. Yearlings fed in the warm season produced heavier carcasses (P less than .05) than calves fed in the cool season. As s.c. fat thickness at slaughter increased, hot carcass weight and numerical yield grade increased, whereas REA per 100 kg of hot carcass decreased. Marbling also increased as fatness increased up to about 1.5 cm subcutaneous fat. PMID:2401646

  11. Performance qualification and Raman investigation on cell behavior and aging of LiFePO4 cathodes in lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Salehi, Amir

    This thesis explores the ability of Raman spectroscopy to understand the complex chemistry taking place in LiFePO4 cathodes of Li ion batteries. The performance of Li ion batteries was optimized through electrode fabrication and assembling procedures. Various amounts of Timcal Super P carbon were used to construct a conductive network of C-LiFePO4 particles and the performance of the cathodes was examined during battery cycling. Raman spectroscopy along with electrochemical characterization such as charge/ discharge curves, electrochemical impedance spectroscopy and Cyclic Voltammetry was employed for detailed investigation of battery performance and aging. It is found that both quantity and quality of the conductive carbon affect the rate performance and cyclic behavior of the cells. The cathodes with 2% additive carbon showed a faster capacity fading during cycling than that with 10% additive carbon due to a quicker degradation of the conductive network as indicated by sp2/sp3 and ID/IG ratios in Raman spectroscopy results. The rate performance of cathodes with 2%, 10% and 20 % carbon was also compared and a better rate performance was found for 2% carbon. It showed a proper electronic network which is mostly provided by carbon coating along with a large pore size of the cathode which facilitates the electrolyte penetration. Furthermore, in situ Raman spectroscopy was employed to probe electrolyte concentration variation at the cathode LiFePO4 particle surface in an optically transparent lithium ion cell. A Raman laser spot size of 2 microm was applied so that transport dynamics at individual particle surface could be investigated. The variation of Li+ concentration in the LiPF6/ethylene carbonate (EC) + dimethyl carbonate (DMC) electrolyte was determined, for the first time. This was done by monitoring the C--O stretching vibration signal intensity and the corresponding relationship to EC solvation. The electrolyte concentration at the LiFePO 4 particle surface

  12. Performance of Motor Sequences in Children at Heightened vs. Low Risk for ASD: A Longitudinal Study from 18 to 36 Months of Age.

    PubMed

    Focaroli, Valentina; Taffoni, Fabrizio; Parsons, Shelby M; Keller, Flavio; Iverson, Jana M

    2016-01-01

    Recent research shows that motor difficulties are a prominent component of the behavioral profile of autism spectrum disorder (ASD) and are also apparent from early in development in infants who have an older sibling with ASD (High Risk; HR). Delays have been reported for HR infants who do and who do not receive an eventual diagnosis of ASD. A growing body of prospective studies has focused on the emergence of early motor skills primarily during the first year of life. To date, however, relatively little work has examined motor skills in the second and third years. Thus, the present research was designed to investigate motor performance in object transport tasks longitudinally in HR and LR (Low Risk) children between the ages of 18 and 36 months. Participants (15 HR children and 14 LR children) were observed at 18, 24, and 36 months. Children completed two motor tasks, the Ball Task and the Block Task, each of which included two conditions that varied in terms of the precision demands of the goal action. Kinematic data were acquired via two magneto inertial sensors worn on each wrist. In the Block Task, HR children reached more slowly (i.e., mean acceleration was lower) compared to LR children. This finding is in line with growing evidence of early delays in fine motor skills in HR children and suggests that vulnerabilities in motor performance may persist into the preschool years in children at risk for ASD. PMID:27242630

  13. Performance of Motor Sequences in Children at Heightened vs. Low Risk for ASD: A Longitudinal Study from 18 to 36 Months of Age

    PubMed Central

    Focaroli, Valentina; Taffoni, Fabrizio; Parsons, Shelby M.; Keller, Flavio; Iverson, Jana M.

    2016-01-01

    Recent research shows that motor difficulties are a prominent component of the behavioral profile of autism spectrum disorder (ASD) and are also apparent from early in development in infants who have an older sibling with ASD (High Risk; HR). Delays have been reported for HR infants who do and who do not receive an eventual diagnosis of ASD. A growing body of prospective studies has focused on the emergence of early motor skills primarily during the first year of life. To date, however, relatively little work has examined motor skills in the second and third years. Thus, the present research was designed to investigate motor performance in object transport tasks longitudinally in HR and LR (Low Risk) children between the ages of 18 and 36 months. Participants (15 HR children and 14 LR children) were observed at 18, 24, and 36 months. Children completed two motor tasks, the Ball Task and the Block Task, each of which included two conditions that varied in terms of the precision demands of the goal action. Kinematic data were acquired via two magneto inertial sensors worn on each wrist. In the Block Task, HR children reached more slowly (i.e., mean acceleration was lower) compared to LR children. This finding is in line with growing evidence of early delays in fine motor skills in HR children and suggests that vulnerabilities in motor performance may persist into the preschool years in children at risk for ASD. PMID:27242630

  14. Aging Brain, Aging Mind.

    ERIC Educational Resources Information Center

    Selkoe, Dennis J.

    1992-01-01

    Discusses the aging process related to physical changes of the human neural structure involved in learning, memory, and reasoning. Presents evidence that indicates such alterations do not necessarily signal the decline in cognitive function. Vignettes provide images of brain structures involved in learning, memory, and reasoning; hippocampal…

  15. The effect of herbs and their associated essential oils on performance, dietary digestibility and gut microflora in chickens from 7 to 28 days of age.

    PubMed

    Cross, D E; McDevitt, R M; Hillman, K; Acamovic, T

    2007-08-01

    1. The effect of the dietary inclusion of 5 culinary herbs or their essential oils on the growth, digestibility and intestinal microflora status in female broiler chicks was assessed. From 7 to 28 d of age, either a basal control diet without supplement was given or one of 10 others, consisting of the basal diet with either 10 g/kg herb (thyme, oregano, marjoram, rosemary or yarrow) or 1 g/kg of essential oil. 2. Body mass (BM) and feed consumption (AFC) were measured on a weekly basis and used to calculate chick performance. Total viable counts of lactic acid bacteria, coliforms, anaerobes and Clostridium perfringens were determined at 25 d. Apparent nutrient digestibilities were calculated from the measured values for gross energy, nitrogen (N), dry matter (DM) and organic matter, and sialic acid concentration was also measured. 3. Generally, dietary thyme oil or yarrow herb inclusion had the most positive effects on chick performance, while oregano herb and yarrow oil were the poorest supplements. Only thyme and yarrow in these diets had a different effect when used as a herb or oil on weight gain and BM. 4. Dietary treatment had no effect on the intestinal microflora populations, apparent metabolisable energy (AME) or the calculated coefficients of digestibility. Sialic acid concentration was greatest in the birds given dietary thyme oil, compared with all other treatments except those birds receiving marjoram oil, rosemary herb and the controls. However, less sialic acid was excreted in those birds given diets with oregano or rosemary oils, or oregano herb, than in the controls. 5. Plant extracts in diets may therefore affect chick performance, gut health and endogenous secretions, although the chemical composition of the extract appears to be important in obtaining the optimal effects. PMID:17701503

  16. A pilot study evaluating the use of EyeSpy video game software to perform vision screening in school-aged children

    PubMed Central

    Trivedi, Rupal H.; Wilson, M. Edward; Peterseim, M. Millicent; Cole, Kali B.; Teed, Ronald G. W.

    2010-01-01

    Purpose To compare the vision-screening results of school-aged children tested with EyeSpy software and those of children examined by a pediatric ophthalmologist. We also compared combined results of an electronic visual acuity (EVA) tester and stereopsis testing to the results of a professional eye examination. Methods In this pilot study, all children were tested using EyeSpy, an ETDRS EVA tester/stereopsis, and examined (including cycloplegic refraction) by a pediatric ophthalmologist. The order of presentation of the EVA and EyeSpy assessments was assigned randomly. The EyeSpy test was performed twice (using occlusive eyepatch and red-blue dissociative goggles). EyeSpy registered pass or refer results for visual acuity testing at a threshold of 20/32 visual acuity and stereopsis of 300 arcsec. Similar threshold values were used in the EVA/stereopsis testing. Results The average age of 72 subjects was 11.4 ± 2.2 years. Prevalence of visual impairment was 25 of 72 (34.7%) as reported by the professional examination. The sensitivity, specificity, and conventional positive likelihood ratio was 88%, 87%, and 6.8 when EyeSpy was used using a patch; 88%, 74%, and 3.44 when EyeSpy was used with goggles; and 88%, 94%, and 13.79 for EVA/stereospsis, compared to the gold-standard professional eye examination. EyeSpy screening results using a patch were not significantly different than those of a professional examination (p = 0.508). The two results concurred in 63 of 72 (87.5%) subjects. Conclusions EyeSpy software has potential for use as a vision-screening device. EyeSpy using an occlusive patch outperformed EyeSpy using dissociative glasses. PMID:20637666

  17. Age, body weight and backfat thickness at first observed oestrus in crossbred Landrace x Yorkshire gilts, seasonal variations and their influence on subsequence reproductive performance.

    PubMed

    Tummaruk, P; Tantasuparuk, W; Techakumphu, M; Kunavongkrit, A

    2007-05-01

    The objective of the present study was to investigate puberty attainment in crossbred Landrace x Yorkshire (LY) gilts reared under tropical conditions and their subsequent reproductive performance. This study was carried out in a 2400-sow herd over a 1-year period. A total of 696 crossbred LY replacement gilts were included. Faecal samples from 214 gilts were collected to determine the faecal progesterone profiles around the time of first oestrus. Solid-phase 125I-radioimmunoassay was used to determine the progesterone concentrations in the faecal extract. The gilts entered the herd at an average age of 177.5 +/- 12.6 days, 95.7 +/- 10.2 kg body weight (BW) and a backfat thickness (BF) of 12.0 +/- 2.9 mm. On average, the gilts expressed first standing oestrus at 195 days of age, 106 kg of BW and a BF of 13.0 mm. The interval from entry to the gilt pool to the first observed oestrus (EOI) was 24.4 +/- 18.0 days (range 0-88 days). The hormonal profile indicated that the gilts that actually ovulated during the first observed oestrus was 34% (group A), the gilts that had ovulated before the first observed oestrus was 21% (group B) and the gilts that did not ovulate during the first observed oestrus was 45% (group C). During summer the proportion of group A gilts was significantly lower than during the winter and the rainy seasons (P < 0.05). The BW of gilts at entry significantly correlated with the BF at entry (r = 0.31, P < 0.001), the age at entry (r = 0.47, P < 0.001), the BW at first oestrus (r = 0.65, P < 0.001) and the BF at first oestrus (r = 0.33, P < 0.001). An increase of BW at entry of 1 kg resulted in a decrease of EOI of 0.28 days. The age, BW and BF of gilts at the first observed oestrus significantly influenced the total number of piglets born per litter (TB) and the number of piglets born alive per litter (BA) in the first three parities. Gilts expressing their first oestrus between 181 and 200 days had a significantly larger TB than gilts that

  18. Effects of dietary supplementation with an expressed fusion peptide bovine lactoferricin-lactoferrampin on performance, immune function and intestinal mucosal morphology in piglets weaned at age 21 d.

    PubMed

    Tang, Zhiru; Yin, Yulong; Zhang, Youming; Huang, Ruilin; Sun, Zhihong; Li, Tiejun; Chu, Wuying; Kong, Xiangfeng; Li, Lili; Geng, Meimei; Tu, Qiang

    2009-04-01

    Lactoferrin has antimicrobial activity associated with peptide fragments lactoferricin (LFC) and lactoferrampin (LFA) released on digestion. These two fragments have been expressed in Photorhabdus luminescens as a fusion peptide linked to protein cipB. The construct cipB-LFC-LFA was tested as an alternative to antimicrobial growth promoters in pig production. Sixty piglets with an average live body weight of 5.42 (sem 0.59) kg were challenged with enterotoxigenic Escherichia coli and randomly assigned to four treatment groups fed a maize-soyabean meal diet containing either no addition (C), cipB at 100 mg/kg (C+B), cipB-LFC-LFA at 100 mg/kg (C+L) or colistin sulfate at 100 mg/kg (C+CS) for 3 weeks. Compared with C, dietary supplementation with C+L for 3 weeks increased daily weight gain by 21 %, increased recovery from diarrhoea, enhanced serum glutathione peroxidase (GPx), peroxidase (POD) and total antioxidant content (T-AOC), liver GPx, POD, superoxide dismutase and T-AOC, Fe, total Fe-binding capacity, IgA, IgG and IgM levels (P < 0.05), decreased the concentration of E. coli in the ileum, caecum and colon (P < 0.05), increased the concentration of lactobacilli and bifidobacteria in the ileum, caecum and colon (P < 0.05), and promoted development of the villus-crypt architecture of the small intestine. Growth performance was similar between C+L- and C+CS-supplemented pigs. The present results indicate that LFC-LFA is an effective alternative to the feed antibiotic CS for enhancing growth performance in piglets weaned at age 21 d. PMID:18840311

  19. Trends in Neurocognitive Aging

    PubMed Central

    Grady, Cheryl

    2013-01-01

    Preface The availability of neuroimaging technology has spurred a marked increase in the human cognitive neuroscience literature, including the study of cognitive aging. Although there is a growing consensus that the aging brain retains considerable plasticity of function, currently measured primarily by means of functional magnetic resonance imaging, it is less clear how age differences in brain activity relate to cognitive performance. The field also is hampered by the complexity of the aging process itself and the large number of factors that are influenced by age. In this review, current trends and unresolved issues in the cognitive neuroscience of aging are discussed. PMID:22714020

  20. Effect of Supplemental Lutein and Zeaxanthin on Serum, Macular Pigmentation, and Visual Performance in Patients with Early Age-Related Macular Degeneration

    PubMed Central

    Huang, Yang-Mu; Dou, Hong-Liang; Huang, Fei-Fei; Xu, Xian-Rong; Zou, Zhi-Yong

    2015-01-01

    Purpose. To compare the 2-year effect of multiple doses of lutein/zeaxanthin on serum, macular pigmentation, and visual performance on patients with early age-related macular degeneration (AMD). Methods. In this randomized, double-blinded, and placebo-controlled trial, 112 early AMD patients randomly received either 10 mg lutein, 20 mg lutein, a combination of lutein (10 mg) and zeaxanthin (10 mg), or placebo daily for 2 years. Serum concentration of lutein/zeaxanthin, macular pigment optical density (MPOD), visual functions including best-spectacle corrected visual acuity (BCVA), contrast sensitivity (CS), flash recovery time (FRT), and vision-related quality of life (VFQ25) was quantified. Results. Serum lutein concentration and MPOD significantly increased in all the active treatment groups. Supplementation with 20 mg lutein was the most effective in increasing MPOD and CS at 3 cycles/degree for the first 48 weeks. However, they both significantly increased to the same peak value following supplementation with either 10 mg or 20 mg lutein during the intervention. No statistical changes of BCVA or FRT were observed during the trial. Conclusions. Long-term lutein supplementation could increase serum lutein concentration, MPOD, and visual sensitivities of early AMD patients. 10 mg lutein daily might be an advisable long-term dosage for early AMD treatment. PMID:25815324

  1. Influence of source and level of glycerin in the diet on growth performance, liver characteristics, and nutrient digestibility in broilers from hatching to 21 days of age.

    PubMed

    Mandalawi, H A; Kimiaeitalab, M V; Obregon, V; Menoyo, D; Mateos, G G

    2014-11-01

    The influence of source and level of inclusion of raw glycerin (GLYC) in the diet on growth performance, digestive traits, total tract apparent retention (TTAR), and apparent ileal digestibility of nutrients was studied in broilers from 1 to 21 d of age. There was a control diet based on corn and soybean meal and 8 additional diets that formed a 2 × 4 factorial with 2 sources of GLYC and 4 levels of inclusion (2.5, 5.0, 7.5, and 10%). The GLYC used were obtained from the same original batch of soy oil that was dried under different processing conditions and contained 87.5 or 81.6% glycerol, respectively. Type of processing of the GLYC did not affect any of the variables studied except DM and organic matter retention (P < 0.05) that was higher for the 87.5% glycerol diet. From d 1 to 21, feed conversion ratio (FCR) improved linearly (L, P ≤ 0.01) as the GLYC content of the diet increased, but ADG was not affected. On d 21, the relative weight (% BW) of the liver and the digestive tract increased (L, P < 0.01) as the level of GLYC in the diet increased, but lipid concentration in the liver was not affected. The TTAR of DM and organic matter increased quadratically (Q, P < 0.05) and the AME(n) content of the diet increased linearly (L, P < 0.01) with increases in dietary GLYC. Also, the apparent ileal digestibility of DM (L, P < 0.05; Q, P = 0.07) and gross energy (L, P < 0.01) increased as the GLYC content of the diet increased. It is concluded that raw GLYC from the biodiesel industry can be used efficiently, up to 10% of the diet, as a source of energy for broilers from 1 to 21 d of age and that the energy content of well-processed raw GLYC depends primarily on its glycerol content. PMID:25214552

  2. Performance of Spot Photoscreener in Detecting Amblyopia Risk Factors in Chinese Pre-school and School Age Children Attending an Eye Clinic

    PubMed Central

    Mu, Yajun; Bi, Hua; Ekure, Edgar; Ding, Gang; Wei, Nan; Hua, Ning; Qian, Xuehan; Li, Xiaorong

    2016-01-01

    Purpose To evaluate the effectiveness of Spot photoscreener in detecting amblyopia risk factors meeting 2013 the American Association of Pediatric Ophthalmology and Strabismus (AAPOS) criteria in Chinese preschool and school-age children. Methods One hundred and fifty-five children (310 eyes), aged between 4 to 7 years (5.74 ± 1.2 years) underwent complete ophthalmologic examination, photoscreening, and cycloplegic retinoscopy refraction. The agreement of the results obtained with the photoscreening and retinoscopy was evaluated by linear regression and Bland-Altman plots. The sensitivity and specificity of detecting amblyopia risk factors were calculated based on the AAPOS 2013 guidelines. The overall effectiveness of detecting amblyopia risk factors was analyzed with Receiver Operating Characteristic (ROC) curves. Result The mean refractive errors measured with the Spot were: spherical equivalent (SE) = 0.70 ± 1.99 D, J0 = 0.87 ± 1.01 D, J45 = 0.09 ± 0.60 D. The mean results from retinoscopy were: SE = 1.19 ± 2.22 D, J0 = 0.77 ± 1.00 D, J45 = -0.02 ± 0.45 D. There was a strong linear agreement between results obtained from those two methods (R2 = 0.88, P<0.01). Bland–Altman plot indicated a moderate agreement of cylinder values between the two methods. Based on the criteria specified by the AAPOS 2013 guidelines, the sensitivity and specificity (in respective order) for detecting hyperopia were 98.31% and 97.14%; for detecting myopia were 78.50% and 88.64%; for detecting astigmatism were 90.91% and 80.37%; for detecting anisometropia were 93.10% and 85.25%; and for detection of strabismus was 77.55% and 88.18%. Conclusion The refractive values measured from Spot photoscreener showed a moderate agreement with the results from cycloplegic retinoscopy refraction, however there was an overall myopic shift of -0.49D. The performance in detecting individual amblyopia risk factors was satisfactory, but could be further improved by optimizing criteria based on

  3. Healthy Aging

    MedlinePlus

    ... About Us Contact Us Text size | Print | Healthy Aging This information in Spanish ( en español ) A healthy ... Aging email updates. Enter email address Submit Healthy Aging news Accessibility | Privacy policy | Disclaimers | FOIA | Link to ...

  4. Healthy Aging

    MedlinePlus

    ... A Change Contrast print sign up Share Healthy Aging This category offers tips on how to stay ... with Smell Problems with Taste Skin Care and Aging Sleep and Aging Taking Medicines Talking with Your ...

  5. Aging blepharoplasty.

    PubMed

    Cho, Inchang

    2013-09-01

    In performing upper blepharoplasty in the elderly, looking younger and keeping the eyelids harmonious with the rest of the face have to be achieved at the same time. The most important goal in upper blepharoplasty for aging is correcting the drooping upper eyelid skin, and in this process, the surgeon may or may not create a double eyelid fold. The pros and cons have to be fully discussed with the patient, but the author personally prefers creating a double fold unless the patient refuses, because it is efficient in correcting and preventing further drooping of the skin. In most patients, the brow is elevated to compensate for the drooping eyelid, and when the drooping is corrected, brow ptosis may ensue. The surgeon has to prepare for these consequences before performing the procedure, and estimate the exact amount of skin to be excised. In the elderly, the skin and the orbicularis oculi muscle is thin, with a decreased amount of subcutaneous fat and retro-orbicularis oculi fat, and in most cases, excision of the skin alone is enough to correct the deformity. Removing large portions of soft tissue may also prolong the recovery period. Unlike younger patients, the lower skin flap should not be stretched too much in the elderly, as it may create an aggressive looking appearance. A few wrinkles in the lower flap should remain untouched to create a natural look. In this article, the author's own methods of performing an aging blepharoplasty are described specifically, with a step-by-step guide and surgical tips. PMID:24086798

  6. English Language Learners' Nonword Repetition Performance: The Influence of Age, L2 Vocabulary Size, Length of L2 Exposure, and L1 Phonology

    ERIC Educational Resources Information Center

    Duncan, Tamara Sorenson; Paradis, Johanne

    2016-01-01

    Purpose: This study examined individual differences in English language learners' (ELLs) nonword repetition (NWR) accuracy, focusing on the effects of age, English vocabulary size, length of exposure to English, and first-language (L1) phonology. Method: Participants were 75 typically developing ELLs (mean age 5;8 [years;months]) whose exposure to…

  7. Age-Related Change of the Mean Level and Intraindividual Variability of Saccadic Reaction Time Performance in Persons with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Haishi, Koichi; Okuzumi, Hideyuki; Kokubun, Mitsuru

    2013-01-01

    The current study examined age-related change of saccadic reaction time (SRT) in persons with intellectual disabilities (ID). Participants were 29 persons with intellectual disabilities aged between 14 and 34 years whose IQs were between 14 and 70. Participants were divided into Group I (IQ greater than or equal to 35) and Group II (IQ less than…

  8. Effects of elevated CO{sub 2}, soil nutrient levels, and foliage age on the performance of two generations of Neodiprion lecontei (Hymenoptera: Diprionidae) feeding on loblolly pine

    SciTech Connect

    Williams, R.S. |; Thomas, R.B.; Strain, B.R.; Lincoln, D.E.

    1997-12-01

    We investigated how changes in loblolly pine needle phytochemistry caused by elevated CO{sub 2}, leaf age, and soil nutrient levels affected the performance of 2 individual generations of the multivoltine folivorous insect pest Neodiprion lecontei. In 2 feeding trials, mature needles produced in the previous (spring) and current (fall) year from seedlings grown in open-topped chambers under 4 CO{sub 2} and 2 soil nutrient levels were fed to 2 separate generations of red beaded pine sawfly larvae. Strong seasonal differences (i.e., spring versus fall) in leaf nutritional and defensive constituents resulted in significant between-generation differences in the growth, consumption, and growth efficiency of sawfly larvae. Enriched CO{sub 2}-grown needles bad higher levels of starch and starch/nitrogen ratios in older, overwintering spring needles, which were lower in leaf nitrogen and monoterpenes than younger, current year needles (fall). Overall, larval growth was higher and consumption lower on the fall needles, presumably because of higher levels of leaf nitrogen compared with the spring needles. The plant CO{sub 2} concentration significantly contributed to the larval consumption responses between seasons (significant CO{sub 2} X season interaction), demonstrating that the 2 sawfly generations were affected differently by CO{sub 2}-induced phytochemical alterations in spring versus fall needles. The data presented here suggests that when investigating multivoltine folivorous insect responses to elevated CO{sub 2}-grown tree seedlings in which multiple leaf flushes within a growing season expose insects to an array of leaf phytochemical changes, >1 insect generation should be investigated. 54 refs., 3 figs., 1 tab.

  9. Neuropsychological Performance and Family History in Children at Age 7 who Develop Adult Schizophrenia or Bipolar Psychosis in the New England Family Studies

    PubMed Central

    Seidman, Larry J.; Cherkerzian, Sara; Goldstein, Jill M.; Agnew-Blais, Jessica; Tsuang, Ming T.; Buka, Stephen L.

    2013-01-01

    Objective Persons developing schizophrenia (SCZ) manifest various premorbid neuropsychological deficits, studied most often by measures of IQ. Far less is known about premorbid neuropsychological functioning in individuals who later develop bipolar psychoses (BP). We evaluated the specificity and impact of family history (FH) of psychosis on premorbid neuropsychological functioning. Methods We conducted a nested case-control study investigating the associations of neuropsychological data systematically collected at age 7 years for 99 adults with psychotic diagnoses (including 45 SCZ and 35 BP) and 101 controls, drawn from the New England cohort of the Collaborative Perinatal Project. A mixed model approach evaluated Full Scale IQ, four neuropsychological factors derived from principal components analysis, and the profile of 10 intelligence and achievement tests, controlling for maternal education, race, and intrafamilial correlation. We used a deviant responder approach (< 10%tile) to calculate rates of impairment. Results There was a significant linear trend, with the SCZ group performing worst. The profile of childhood deficits for persons with SCZ did not differ significantly from BP. 42.2% of SCZ, 22.9% of BP, and 7% of controls were neuropsychologically impaired. Presence of psychosis in first-degree relatives (FH+) significantly increased the severity of childhood impairment for SCZ but not for BP. Conclusions Premorbid neuropsychological deficits are found in a substantial proportion of children who later develop SCZ, especially in the SCZ FH+ subgroup, but less so in BP, suggesting especially impaired neurodevelopment underlying cognition in pre-SCZ children. Future work should assess genetic and environmental factors that explain this FH effect. PMID:22575089

  10. Effects of beta-hydroxy-beta-methylbutyrate (HMB) on exercise performance and body composition across varying levels of age, sex, and training experience: A review

    PubMed Central

    Wilson, Gabriel J; Wilson, Jacob M; Manninen, Anssi H

    2008-01-01

    The leucine metabolite beta-hydroxy-beta-methylbutyrate (HMB) has been extensively used as an ergogenic aid; particularly among bodybuilders and strength/power athletes, who use it to promote exercise performance and skeletal muscle hypertrophy. While numerous studies have supported the efficacy of HMB in exercise and clinical conditions, there have been a number of conflicting results. Therefore, the first purpose of this paper will be to provide an in depth and objective analysis of HMB research. Special care is taken to present critical details of each study in an attempt to both examine the effectiveness of HMB as well as explain possible reasons for conflicting results seen in the literature. Within this analysis, moderator variables such as age, training experience, various states of muscle catabolism, and optimal dosages of HMB are discussed. The validity of dependent measurements, clustering of data, and a conflict of interest bias will also be analyzed. A second purpose of this paper is to provide a comprehensive discussion on possible mechanisms, which HMB may operate through. Currently, the most readily discussed mechanism has been attributed to HMB as a precursor to the rate limiting enzyme to cholesterol synthesis HMG-coenzyme A reductase. However, an increase in research has been directed towards possible proteolytic pathways HMB may operate through. Evidence from cachectic cancer studies suggests that HMB may inhibit the ubiquitin-proteasome proteolytic pathway responsible for the specific degradation of intracellular proteins. HMB may also directly stimulate protein synthesis, through an mTOR dependent mechanism. Finally, special care has been taken to provide future research implications. PMID:18173841

  11. Research on the non-thermal DBD surface modification and the humidity-heat aging resistant performance in solar cell modules of FFC backsheet

    NASA Astrophysics Data System (ADS)

    Si, Qiong; Fei, Zhihuang; Jin, Jing; Qiu, Huayu; Zhang, Yuzheng

    2009-08-01

    The plasma generated by dielectric barrier discharge(DBD) with the atmosphere of lasting modifying materials, gives modification to the surfaces of FFC backsheet, which is formed by coating FFC (a tetra-fluoro based material with high content of fluorine) on the double-surfaces of polyester(PET). The research on the character of FFC backsheet before and after DBD modification is hold through a series analyzing ways, such as measuring the surface contact angles and surface energy of FFC backsheet with different plasma modification time and different DBD power density, comparing the preservation of surface energy of FFC backsheet with different storage medium and storage period, observing the surfaces of FFC backsheet through scanning electron microscope(SEM), making use of Fourier transform attenuated total reflectance infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). Meanwhile, the soalr cell modules using FFC backsheet and other backsheets are tested under the condition of 85centigrade×85%RH to make comparison between FFC backsheet and other backsheets in various aspects, like the peel strength between backsheet and EVA and so on. All the tests show both the microscopic appearance and surface chemical composition of FFC backsheet is changed after the DBD plasma modification with the atmosphere of lasting modifying materials. After the DBD plasma modifications with a power density of 4.07W/cm2 and different modification time, the water contact angle for FFC backsheet surface is reduced from 82° to 38°. Comparing with other types of backsheets as the solar cell modules encapsulant materials, FFC backsheet has obvious advantage in humit-heat aging resistant performance of the peel strength with EVA and other respects.

  12. Myocontrol in Aging

    PubMed Central

    Fimbel, Eric J.; Arguin, Martin

    2007-01-01

    Myoelectric (EMG) signals are used in assistive technology for prostheses, computer and domestic control. An experimental study previously conducted with young participants was replicated with elderly persons in order to assess the effect of age on the ability to control myoelectric amplitude (or myocontrol). Participants performed pointing tasks as the myoelectric amplitude was captured by a surface electrode in two modalities (sustained: stabilize the amplitude after reaching the desired level; impulsion: return immediately to resting amplitude). There was a significant decrease of performance with Age. However, the patterns of performance of young and aged were noticeably similar. The Impulsion modality was difficult (high rates of failure) and the speed-accuracy trade-offs predicted by Fitts' law were absent (bow-shaped patterns as function of target amplitude instead of logarithmic increase). Conversely, the reach phase of the Sustained modality followed the predictions of Fitts' law. However, the slope of the regression line with Fitts' index of difficulty was quite steeper in aged than in young participants. These findings suggest that 1) all participants, young and aged, adapt their reaching strategies to the anticipated state (sustained amplitude or not) and/or to the difficulty of the task, 2) myocontrol in aged persons is more fragile, i.e., performance is markedly degraded as the difficulty of the task increases. However, when individual performance was examined, some aged individuals were found to perform as well as the young participants, congruently with the literature on good aging. PMID:18030349

  13. Increased participation and improved performance in age group backstroke master swimmers from 25-29 to 100-104 years at the FINA World Masters Championships from 1986 to 2014.

    PubMed

    Unterweger, Chiara M; Knechtle, Beat; Nikolaidis, Pantelis T; Rosemann, Thomas; Rüst, Christoph A

    2016-01-01

    Participation and performance trends in age group athletes have been investigated for different sport disciplines, but not for master swimmers. The knowledge on this topic is still missing for a particular stroke such as backstroke. Changes in participation and performance of male and female age group backstroke swimmers (≥25 years) competing in 50, 100 and 200 m pool swimming at the FINA World Masters Championships held between 1986 and 2014 were investigated using mixed-effects regression analyses. The overall participation was n = 26,217 including n = 13,708 women and n = 12,509 men. In 50 m, female (age groups 85-89 years; p = 0.002) and male participation (age groups 55-59; p = 0.030 and 80-84 years; p = 0.002) increased, while female participation decreased in age groups 55-59 (p = 0.010) and 60-64 years (p = 0.050). In 100 and 200 m, participation increased in age groups 45-49, 50-54, 65-69, 70-74, 80-84 years. Swimmers in age groups 25-29 to 95-99 years improved performance over all distances. Women were slower than men in age groups 25-29 to 80-84 years, but not in age groups 85-89 to 95-99 years over all distances. In 50 m and 100 m, the sex difference decreased in age groups 40-44 (p = 0.007 and p = 0.005), 45-49 (p = 0.017 and p = 0.034), 50-54 (p = 0.002 and p = 0.040), to 55-59 years (p = 0.002 and p = 0.004). In 200 m, the sex difference decreased in age groups 40-44 (p = 0.044) and 90-94 (p = 0.011), but increased in age group 25-29 years (p = 0.006). In summary, in age group backstroke swimmers, (1) participation increased or remained unchanged (except women in age groups 55-59 and 60-64 years in 50 m), (2) swimming performance improved in all age groups from 25-29 to 95-99 years over all distances, (3) men were faster than women in age groups 25-29 to 80-84 years (except age groups 85-89 to 95-99 years) over time and all distances. PMID:27330911

  14. Age-related slowing of myosin actin cross-bridge kinetics is sex specific and predicts decrements in whole skeletal muscle performance in humans

    PubMed Central

    Bedrin, Nicholas G.; Callahan, Damien M.; Previs, Michael J.; Jennings, Mark E.; Ades, Philip A.; Maughan, David W.; Palmer, Bradley M.; Toth, Michael J.

    2013-01-01

    We hypothesize that age-related skeletal muscle dysfunction and physical disability may be partially explained by alterations in the function of the myosin molecule. To test this hypothesis, skeletal muscle function at the whole muscle, single fiber, and molecular levels was measured in young (21–35 yr) and older (65–75 yr) male and female volunteers with similar physical activity levels. After adjusting for muscle size, older adults had similar knee extensor isometric torque values compared with young, but had lower isokinetic power, most notably in women. At the single-fiber and molecular levels, aging was associated with increased isometric tension, slowed myosin actin cross-bridge kinetics (longer myosin attachment times and reduced rates of myosin force production), greater myofilament lattice stiffness, and reduced phosphorylation of the fast myosin regulatory light chain; however, the age effect was driven primarily by women (i.e., age-by-sex interaction effects). In myosin heavy chain IIA fibers, single-fiber isometric tension and molecular level mechanical and kinetic indexes were correlated with whole muscle isokinetic power output. Collectively, considering that contractile dysfunction scales up through various anatomical levels, our results suggest a potential sex-specific molecular mechanism, reduced cross-bridge kinetics, contributes to the reduced physical capacity with aging in women. Thus these results support our hypothesis that age-related alterations in the myosin molecule contribute to skeletal muscle dysfunction and physical disability and indicate that this effect is stronger in women. PMID:23887900

  15. The effects of JWB1-84-1 on memory-related task performance by amyloid Abeta transgenic mice and by young and aged monkeys.

    PubMed

    Sood, Ajay; Warren Beach, J; Webster, Scott J; Terry, Alvin V; Buccafusco, Jerry J

    2007-10-01

    JWB1-84-1 is one of 50 tertiary amine analogs of choline synthesized with expectation that they would be high potency compounds for cytoprotection. As one of the more potent analogs in this regard, JWB1-84-1, a piperazine derivative, was selected for testing as a cognition-enhancing agent. The compound was evaluated for efficacy in Alzheimer's disease transgenic mice (B6C3-Tg(APPswe, PSEN1dE9)85Dbo/J). A separate cohort of mice (AD Tg) were first subjected to a behavioral test battery in which the transgenic strain was compared with the wild-type strain. AD Tg mice were shown to exhibit specific deficits in the acquisition of a working memory (5-trial/session radial arm water maze, RAWM) task at a time when the animals exhibited maximal cerebral amyloid burden. JWB1-84-1 produced a dose-dependent decrease in the number of errors made by well trained AD-Tg mice the RAWM task that was maximal after the 20 microg/kg dose. Aged macaques (20-32 y) were trained to proficiency in their performance of a computer-assisted delayed matching-to-sample task. Vehicle (normal saline) or JWB1-84-1 (5-150 microg/kg, i.m.) was administered 10 min before the initiating of testing. On average, JWB1-84-1 treatment significantly improved task accuracy after all but the lowest dose. The maximal degree of improvement was attained after animals received the 100 microg/kg dose. The drug's effects were restricted primarily to Medium and Long delay trials - the most difficult portions of the task, which were improved by up to 18% above control. In young macaques JWB1-84-1 treatment also significantly reversed the decrements in task accuracy associated with the random presentation of a task distractor. Thus JWB1-84-1exhibits the potential for treating the cognitive symptoms associated with neurodegenerative diseases and attention deficit disorders. Its cytoprotective action might also work to slow the progression of Alzheimer's disease. PMID:17698153

  16. Puzzling With Online Games (BAM-COG): Reliability, Validity, and Feasibility of an Online Self-Monitor for Cognitive Performance in Aging Adults

    PubMed Central

    Baars, Maria A E; Olde Rikkert, Marcel G M; Kessels, Roy P C

    2013-01-01

    Background Online interventions are aiming increasingly at cognitive outcome measures but so far no easy and fast self-monitors for cognition have been validated or proven reliable and feasible. Objective This study examines a new instrument called the Brain Aging Monitor–Cognitive Assessment Battery (BAM-COG) for its alternate forms reliability, face and content validity, and convergent and divergent validity. Also, reference values are provided. Methods The BAM-COG consists of four easily accessible, short, yet challenging puzzle games that have been developed to measure working memory (“Conveyer Belt”), visuospatial short-term memory (“Sunshine”), episodic recognition memory (“Viewpoint”), and planning (“Papyrinth”). A total of 641 participants were recruited for this study. Of these, 397 adults, 40 years and older (mean 54.9, SD 9.6), were eligible for analysis. Study participants played all games three times with 14 days in between sets. Face and content validity were based on expert opinion. Alternate forms reliability (AFR) was measured by comparing scores on different versions of the BAM-COG and expressed with an intraclass correlation (ICC: two-way mixed; consistency at 95%). Convergent validity (CV) was provided by comparing BAM-COG scores to gold-standard paper-and-pencil and computer-assisted cognitive assessment. Divergent validity (DV) was measured by comparing BAM-COG scores to the National Adult Reading Test IQ (NART-IQ) estimate. Both CV and DV are expressed as Spearman rho correlation coefficients. Results Three out of four games showed adequate results on AFR, CV, and DV measures. The games Conveyer Belt, Sunshine, and Papyrinth have AFR ICCs of .420, .426, and .645 respectively. Also, these games had good to very good CV correlations: rho=.577 (P=.001), rho=.669 (P<.001), and rho=.400 (P=.04), respectively. Last, as expected, DV correlations were low: rho=−.029 (P=.44), rho=−.029 (P=.45), and rho=−.134 (P=.28

  17. NH3-SCR performance of fresh and hydrothermally aged Fe-ZSM-5 in standard and fast selective catalytic reduction reactions.

    PubMed

    Shi, Xiaoyan; Liu, Fudong; Xie, Lijuan; Shan, Wenpo; He, Hong

    2013-04-01

    Hydrothermal stability is one of the challenges for the practical application of Fe-ZSM-5 catalysts in the selective catalytic reduction (SCR) of NO with NH3 (NH(3)-SCR) for diesel engines. The presence of NO(3) in the exhaust gases can enhance the deNOx activity because of the fast SCR reaction. In this work, a Fe-ZSM-5 catalyst was prepared by a solid-state ion-exchange method and was hydrothermally deactivated at 800 °C in the presence of 10% H(2)O. The activity of fresh and hydrothermal aged Fe-ZSM-5 catalysts was investigated in standard SCR (NO(2)/NOx = 0) and in fast SCR with NO(2)/NOx = 0.3 and 0.5. In standard SCR, hydrothermal aging of Fe-ZSM-5 resulted in a significant decrease of low-temperature activity and a slight increase in high-temperature activity. In fast SCR, NOx conversion over aged Fe-ZSM-5 was significantly increased but was still lower than that over fresh catalyst. Additionally, production of N(2)O in fast SCR was much more apparent over aged Fe-ZSM-5 than over fresh catalyst. We propose that, in fast SCR, the rate of key reactions related to NO is slower over aged Fe-ZSM-5 than over fresh catalyst, thus increasing the probabilities of side reactions involving the formation of N(2)O. PMID:23477804

  18. The impact of ageing and gender on visual mental imagery processes: A study of performance on tasks from the Complete Visual Mental Imagery Battery (CVMIB).

    PubMed

    Palermo, Liana; Piccardi, Laura; Nori, Raffaella; Giusberti, Fiorella; Guariglia, Cecilia

    2016-09-01

    In this study we aim to evaluate the impact of ageing and gender on different visual mental imagery processes. Two hundred and fifty-one participants (130 women and 121 men; age range = 18-77 years) were given an extensive neuropsychological battery including tasks probing the generation, maintenance, inspection, and transformation of visual mental images (Complete Visual Mental Imagery Battery, CVMIB). Our results show that all mental imagery processes with the exception of the maintenance are affected by ageing, suggesting that other deficits, such as working memory deficits, could account for this effect. However, the analysis of the transformation process, investigated in terms of mental rotation and mental folding skills, shows a steeper decline in mental rotation, suggesting that age could affect rigid transformations of objects and spare non-rigid transformations. Our study also adds to previous ones in showing gender differences favoring men across the lifespan in the transformation process, and, interestingly, it shows a steeper decline in men than in women in inspecting mental images, which could partially account for the mixed results about the effect of ageing on this specific process. We also discuss the possibility to introduce the CVMIB in clinical assessment in the context of theoretical models of mental imagery. PMID:27134072

  19. Skin Aging

    MedlinePlus

    ... too. Sunlight is a major cause of skin aging. You can protect yourself by staying out of ... person has smoked. Many products claim to revitalize aging skin or reduce wrinkles, but the Food and ...

  20. Communication & Aging.

    ERIC Educational Resources Information Center

    Arnold, William E.

    This extensive bibliography contains more than 1,800 entries about communication and aging. The citations include journal articles, unpublished papers, speeches, dissertations, research studies, and books that relate aging and the aged to a variety of topics, including the following: physiological deterioration, socialization, political…

  1. Skin Aging

    MedlinePlus

    Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it ... heal, too. Sunlight is a major cause of skin aging. You can protect yourself by staying out ...

  2. Creative Aging.

    ERIC Educational Resources Information Center

    Ager, Charlene Lee; And Others

    1981-01-01

    Explores some divergent attitudes toward aging, negative as well as positive. Presents a neurophysiological framework to support the belief that aging is an active and creative process. Explores physical, psychological, and sociological aspects, and identifies three factors in the creative aging process. (Author/JAC)

  3. Intakes of (n-3) fatty acids and fatty fish are not associated with cognitive performance and 6-year cognitive change in men participating in the Veterans Affairs Normative Aging Study.

    PubMed

    van de Rest, Ondine; Spiro, Avron; Krall-Kaye, Elizabeth; Geleijnse, Johanna M; de Groot, Lisette C P G M; Tucker, Katherine L

    2009-12-01

    High intake of fish and (n-3) PUFA may protect against age-related cognitive decline. However, results are inconsistent and limited data exist regarding changes in multiple cognitive functions over a longer period of time. In this study, we assessed the association between fatty fish intake as well as (n-3) PUFA intake with cognitive performance and cognitive change over 6 y in 1025 elderly men. Participants were from the Veterans Affairs Normative Aging Study. Cognitive function was assessed with a battery of cognitive tests focusing on factors representing memory/language, speed, and visuospatial/attention. Dietary intakes were assessed with a validated FFQ. We used general linear models to assess cross-sectional associations and mixed models to assess the associations over time. Models were adjusted for age, education, BMI, smoking, diabetes, and intake of alcohol, saturated fat, vitamin C, and vitamin E. The mean age of participating men was 68 y at baseline. Median fish consumption ranged from 0.2 to 4.2 servings/wk across quartiles. Cross-sectional analyses showed no association between fatty fish or (n-3) PUFA intake and cognitive performance. Longitudinal analyses, over 6 y of follow-up, also did not show any significant associations between fatty fish or (n-3) PUFA intake and cognitive change. In this population of elderly men, intake of neither fatty fish nor (n-3) PUFA was associated with cognitive performance. PMID:19828689

  4. Does the School Performance Variable Used in the International Health Behavior in School-Aged Children (HBSC) Study Reflect Students' School Grades?

    ERIC Educational Resources Information Center

    Felder-Puig, Rosemarie; Griebler, Robert; Samdal, Oddrun; King, Matthew A.; Freeman, John; Duer, Wolfgang

    2012-01-01

    Background: Given the pressure that educators and policy makers are under to achieve academic standards for students, understanding the relationship of academic success to various aspects of health is important. The international Health Behavior in School-Aged Children (HBSC) questionnaire, being used in 41 countries with different school and…

  5. Comparative performance of current definitions of sarcopenia against the prospective incidence of falls among community dwelling seniors age 65 and older

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Purpose: To compare the extent to which 7 available definitions of sarcopenia and 2 related definitions predict the prospective rate of falling. Methods: We studied a cohort of 445 seniors (mean age 71 years, 45% men) living in the community who were followed with a detailed fall assessment for 3 ...

  6. Age-related differences in acquisiton, steady-state performance and carbaryl effects on the operant behavior of Brown Norway rats.

    EPA Science Inventory

    The rapid increase in older adults in the population highlights the importance of understanding the role of aging in susceptibility to environmental contaminants. As part of a larger program on life-stage susceptibility, this experiment determined the effect of the carbamate pest...

  7. Children's Search Strategies and Accompanying Verbal and Motor Strategic Behavior: Developmental Trends and Relations with Task Performance among Children Age 5 to 17

    ERIC Educational Resources Information Center

    Winsler, Adam; Naglieri, Jack; Manfra, Louis

    2006-01-01

    Children's reported use of single and multiple search strategies during a matching numbers task, along with accompanying verbal (private speech, self-talk) and motoric (finger pointing, place-holding) strategic behaviors were examined with a large, nationally representative cross-sectional sample ("n"=1,979) of children between the ages of 5 and…

  8. Psychological Assessment through Performance-Based Techniques and Self-Reports: A Case Study of a Sexually Abused Girl at Preschool Age

    ERIC Educational Resources Information Center

    Khalily, Muhammad Tahir; Hallahan, Brian

    2011-01-01

    We investigated the implicit psychological and behavioral consequences of sexual abuse in an adolescent girl who suffered child sexual abuse at preschool age in this case report. We report the manifestations of this abuse on her personality and psychological functioning using a structured clinical interview and a comprehensive psychological…

  9. Effects of Sentence Instruction and Frequency Building to a Performance Criterion on Elementary-Aged Students with Behavioral Concerns and EBD

    ERIC Educational Resources Information Center

    Datchuk, Shawn M.; Kubina, Richard M.; Mason, Linda H.

    2015-01-01

    Elementary-aged students with behavioral concerns and disabilities struggling to construct sentences stand a high likelihood for continued academic difficulty. Several studies have used sentence instruction with picture-word prompts to improve sentence level writing skills, including construction of simple sentences, syntax, capitalization, and…

  10. The Impact of Developmental Mathematics Courses and Age, Gender, and Race and Ethnicity on Persistence and Academic Performance in Virginia Community Colleges

    ERIC Educational Resources Information Center

    Wolfle, James D.; Williams, Mitchell R.

    2014-01-01

    This research study examined the 2006 cohort of First-Time-in-College students from all 23 community colleges in Virginia. The goal was to examine fall-to-fall persistence and success in the first college-level mathematics course. Predictor variables used were developmental status, age, gender, and race and ethnicity of the student. Interaction…

  11. Associations of vitamin D status, bone health and anthropometry, with gross motor development and performance of school-aged Indian children who were born at term with low birth weight

    PubMed Central

    Filteau, Suzanne; Rehman, Andrea M; Yousafzai, Aisha; Chugh, Reema; Kaur, Manpreet; Sachdev, H P S; Trilok-Kumar, Geeta

    2016-01-01

    Objectives There is little information regarding motor development of children born at term with low birth weight (LBW), a group that constitutes a large proportion of children in South Asia. We used data from infancy and at school age from a LBW cohort to investigate children's motor performance using causal inference. Design Cross-sectional follow-up study. Setting Delhi, India. Participants We recruited 912 children aged 5 years who had participated in a trial of vitamin D for term LBW infants in the first 6 months of life. Outcome measures We focused on gross motor development, using the Ages and Stages Questionnaire (ASQ) gross motor scale and several measures of motor performance. We examined the effects on these of current anthropometry, vitamin D status and bone health, controlling for age, sex, season of interview, socioeconomic variables, early growth, recent morbidity, sun exposure and animal food intake. Results In adjusted analyses, stunted children (height-for-age Z (HAZ) <−2) took longer to run 20 m (0.52 s, 95% CI 0.35 to 0.70; p<0.001) and had greater odds of a failing score on the ASQ (OR 3.00, 95% CI 1.41 to 6.38, p=0.004). Greater arm muscle area was associated with faster run time, and the ability to perform more stands and squats in 15 s. Poorer vitamin D status was associated with the ability to perform more stands and squats. Lower tibia ultrasound Z score was associated with greater hand grip strength. Early growth and current body mass index had no associations with motor outcomes. Conclusions Current HAZ and arm muscle area showed the strongest associations with gross motor outcomes, likely due to a combination of simple physics and factors associated with stunting. The counterintuitive inverse associations of tibia health and vitamin D status with outcomes may require further research. PMID:26747034

  12. Inclusion of tallow and soybean oil to calf starters fed to dairy calves from birth to four months of age on calf performance and digestion.

    PubMed

    Hill, T M; Bateman, H G; Aldrich, J M; Quigley, J D; Schlotterbeck, R L

    2015-07-01

    Energy demands for calves can increase during periods of heat and cold stress. One way to potentially increase energy intake is to increase the energy density of the feed with fat. Trial 1a compared a control starter with no added fat or oil (CON) to starters with 2% tallow (TAL) and 2% soybean oil (SBO). Starters were 20% crude protein (CP) and 45 to 47% starch. Male Holstein calves that were initially 3 to 5d of age were fed a 27% CP, 17% fat milk replacer at 0.66kg of dry matter daily and fully weaned by 42d of a 56-d trial. Trial 1b estimated the digestion of the diets (employed chromic oxide as an indigestible digesta flow marker) using a subset of 5 weaned calves per treatment between d 52 and 56. Trial 2 used Holstein calves initially 59 to 61d of age fed starters CON and SBO blended with 5% chopped grass hay over a 56-d trial. Trial 3 used Holstein calves initially 59 to 61d of age fed starters CON and TAL blended with 5% chopped grass hay over a 56-d trial. Treatments were compared using repeated measures (where appropriate) in a completely randomized design. In trials 1a and 1b, preplanned contrasts compared CON versus TAL and CON versus SBO. Compared with CON, calves fed SBO had reduced starter intake, average daily gain, and digestion of dry matter, organic matter, and CP before 8wk of age. Compared with CON, calves fed SBO had reduced average daily gain and change in hip width from 2 to 4 mo of age. Compared with CON, calves fed TAL had reduced average daily gain and tended to have reduced change in hip width from 2 to 4 mo of age. Calculated metabolizable energy intake was not increased in any trial by added fat or oil. Tallow and soybean oil inclusion at 2% of the starter feed was not advantageous for calf growth before 4 mo of age. PMID:25912868

  13. Mosaic aging

    PubMed Central

    Walker, Lary C.; Herndon, James G.

    2010-01-01

    Summary Although all multicellular organisms undergo structural and functional deterioration with age, senescence is not a uniform process. Rather, each organism experiences a constellation of changes that reflect the heterogeneous effects of age on molecules, cells, organs and systems, an idiosyncratic pattern that we refer to as mosaic aging. Varying genetic, epigenetic and environmental factors (local and extrinsic) contribute to the aging phenotype in a given individual, and these agents influence the type and rate of functional decline, as well as the likelihood of developing age-associated afflictions such as cardiovascular disease, arthritis, cancer, and neurodegenerative disorders. Identifying key factors that drive aging, clarifying their activities in different systems, and in particular understanding how they interact will enhance our comprehension of the aging process, and could yield insights into the permissive role that senescence plays in the emergence of acute and chronic diseases of the elderly. PMID:20110150

  14. Psychological assessment through performance-based techniques and self-reports: a case study of a sexually abused girl at preschool age.

    PubMed

    Khalily, Muhammad Tahir; Hallahan, Brian

    2011-05-01

    We investigated the implicit psychological and behavioral consequences of sexual abuse in an adolescent girl who suffered child sexual abuse at preschool age in this case report. We report the manifestations of this abuse on her personality and psychological functioning using a structured clinical interview and a comprehensive psychological battery including the Beck Anxiety Inventory, the Beck Depression Inventory, the Standard Progressive Matrices, Rorschach Ink Blots, and the Schema Mode Inventory. These investigations were useful in formulating both a diagnosis and a management plan. The girl fulfilled diagnostic criteria for a major depressive episode and borderline personality disorder. This combination of psychological testing may be useful in establishing an accurate multiaxial diagnosis and for understanding the behavioral and psychological sequelae of child sexual abuse in similar cases. The study further suggests that schema-focused therapy is a useful therapeutic tool for individuals who have suffered child sexual abuse at an early age and who have borderline personality disorder. PMID:21660818

  15. Age-related change of the mean level and intraindividual variability of saccadic reaction time performance in persons with intellectual disabilities.

    PubMed

    Haishi, Koichi; Okuzumi, Hideyuki; Kokubun, Mitsuru

    2013-03-01

    The current study examined age-related change of saccadic reaction time (SRT) in persons with intellectual disabilities (ID). Participants were 29 persons with intellectual disabilities aged between 14 and 34 years whose IQs were between 14 and 70. Participants were divided into Group I (IQ≧35) and Group II (IQ≦34). The mean and the standard deviation of SRT (SRTM and SRTSD, respectively) reduced through adolescence in both groups. This result suggests that the speed and stability of information processing develops during adolescence irrespective of the level of ID. Although SRTM and SRTSD of Group I stabilized after adolescence, those of Group II increased after their thirties. This outcome indicates that persons with severe ID may show signs of the aging process. The results of multiple regression analyses and path analyses indicated that SRTM was influenced by both the speed of information processing and the variability of the response. However, given that the extent of increase of SRTSD in Group II was smaller as compared with that of SRTM, this increase of SRTM after the thirties in Group II appears to be mainly affected by the slowness of information processing. PMID:23291514

  16. The Effect of Picture Task Cards on Performance of the Test of Gross Motor Development by Preschool-Aged Children: A Preliminary Study

    ERIC Educational Resources Information Center

    Breslin, Casey M.; Robinson, Leah E.; Rudisill, Mary E.

    2013-01-01

    Performance on the Test of Gross Motor Development (Second Edition; TGMD-2) by children with autism spectrum disorders improves when picture task cards were implemented into the assessment protocol [Breslin, C.M., & Rudisill, M.E. (2011). "The effect of visual supports on performance of the TGMD-2 for children with autism spectrum disorder."…

  17. Aging gauge

    DOEpatents

    Betts, Robert E.; Crawford, John F.

    1989-04-04

    An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

  18. Aging gauge

    DOEpatents

    Betts, Robert E.; Crawford, John F.

    1989-01-01

    An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

  19. Effect of dietary methionine content on growth performance, carcass traits, and feather growth of Pekin duck from 15 to 35 days of age

    PubMed Central

    Zeng, Q. F.; Zhang, Q.; Chen, X.; Doster, A.; Murdoch, R.; Makagon, M.; Gardner, A.; Applegate, T. J.

    2015-01-01

    A study was conducted to establish the response of Pekin ducks to dietary Met from 15 to 35 d age. Experimental diets were formulated to contain 0.35, 0.45, 0.55, 0.65, and 0.75% Met (0.30, 0.39, 0.45, 0.56, and 0.68% on an analyzed basis, respectively) and 0.3% cysteine (0.25, 0.27, 0.26, 0.26, and 0.28% on an analyzed basis, respectively). Each diet was fed to 10 pens of 55 ducks/pen. Carcass yields and feather growth were determined at 28 and 35 d. Results showed that feeding 0.30% Met (0.55% Met+Cys) significantly impaired ADG, feed-to-gain (F:G) ratio, breast meat yield, and feather growth in comparison to the other dietary treatments (P < 0.05). BW, ADG, F:G, carcass and breast meat weight and yield, breast skin and subcutaneous fat weight and yield, the fourth primary wing feather length, and feather coverage showed significant quadratic broken-line or quadratic polynomial response to increasing dietary Met (P < 0.05). From 15 to 28 d age, the optimal Met requirement for the BW, breast meat yield, and the fourth primary wing feather length were 0.510, 0.445, and 0.404%, respectively, based on quadratic broken-line model, and correspondingly were 0.606, 0.576, and 0.559% by quadratic regression. For ducks from 15 to 35 d age, the optimal Met requirement for BW, breast meat yield, and feather coverage were 0.468, 0.408, and 0.484%, respectively, by quadratic broken-line model, and 0.605, 0.564, and 0.612%, by quadratic regression, respectively. PMID:25971946

  20. Relaxation: its effect on the nutritional status and performance status of clients with cancer.

    PubMed

    Campbell, D F; Dixon, J K; Sanderford, L D; Denicola, M A

    1984-02-01

    Relaxation was used to promote normal food consumption patterns among persons with cancer. As part of a larger study, 22 persons with cancer were randomly assigned to receive instruction and reinforcement in a relaxation technique to be used preprandially. The relaxation procedure included four components: (a) deep abdominal breathing, (b) tensing and relaxing of various body parts, (c) relaxation by autosuggestion, and (d) voluntary image control. Twelve clients complied with relaxation instructions in part, and 10 did not. Among compliers, 75% experienced desirable weight change over a six-week period. Performance status, measured by the Karnofsky scale, improved for 33% and worsened for 17% over eight weeks. Research has shown relaxation to be an effective measure in relation to pain, hypertension, and other conditions. These preliminary results now suggest that relaxation may also be effective in treating the eating problems of the person with cancer, leading to improvement in weight and performance status. PMID:6363490

  1. Dietary threonine response of Pekin ducks from hatch to 14 d of age based on performance, serology, and intestinal mucin secretion.

    PubMed

    Zhang, Q; Zeng, Q F; Cotter, P; Applegate, T J

    2016-06-01

    Two experiments were conducted to determine the dietary threonine (Thr) requirement of Pekin ducks from hatch to 14 d of age. In experiment 1, practical corn-soybean meal diets were formulated to contain 0.78, 0.84, 0.90, 0.96, and 1.02% Thr (0.74, 0.83, 0.88, 0.92, and 1.00% Thr on an analyzed basis). In experiment 2, corn-soybean meal diets supplemented with 11 crystalline amino acids were formulated to contain 0.60, 0.70, 0.80, 0.90, 1.00, and 1.10% Thr (0.60, 0.75, 0.89, 0.95, 1.01, and 1.09% Thr on an analyzed basis). In both experiments, diets were fed to 8 replicate cages with 6 male ducks per cage. Body weight and feed intake from each cage were recorded weekly. At 14 d of age, breast meat, ileal digesta, and serum were collected to determine breast meat yield, mucin secretion, and serology parameters. In both studies, the estimated Thr requirement (expressed as % dietary Thr basis) for 14 d BW and BW gain (BWG) by quadratic broken-line (QBL) regression were similar, which were 0.87 and 0.86%, respectively. Additional measures in both experiments resulted in Thr requirements via QBL regression in rank order of crude mucin secretion < breast meat yield < serum immune activity. Summing up the estimates from both studies, the Thr requirement ranged from a low of 0.81% to maximize feed intake (FI) to a high of 1.00% to maximize serum Rb L100 by QBL regression. Correspondingly, the Thr requirement varied between a low of 0.90% to maximize crude mucin secretion on a dry matter intake (DMI) basis and a high of 0.98% to maximize feed-to-gain when using quadratic regression. PMID:26944967

  2. Radiomic Profiling of Glioblastoma: Identifying an Imaging Predictor of Patient Survival with Improved Performance over Established Clinical and Radiologic Risk Models.

    PubMed

    Kickingereder, Philipp; Burth, Sina; Wick, Antje; Götz, Michael; Eidel, Oliver; Schlemmer, Heinz-Peter; Maier-Hein, Klaus H; Wick, Wolfgang; Bendszus, Martin; Radbruch, Alexander; Bonekamp, David

    2016-09-01

    Purpose To evaluate whether radiomic feature-based magnetic resonance (MR) imaging signatures allow prediction of survival and stratification of patients with newly diagnosed glioblastoma with improved accuracy compared with that of established clinical and radiologic risk models. Materials and Methods Retrospective evaluation of data was approved by the local ethics committee and informed consent was waived. A total of 119 patients (allocated in a 2:1 ratio to a discovery [n = 79] or validation [n = 40] set) with newly diagnosed glioblastoma were subjected to radiomic feature extraction (12 190 features extracted, including first-order, volume, shape, and texture features) from the multiparametric (contrast material-enhanced T1-weighted and fluid-attenuated inversion-recovery imaging sequences) and multiregional (contrast-enhanced and unenhanced) tumor volumes. Radiomic features of patients in the discovery set were subjected to a supervised principal component (SPC) analysis to predict progression-free survival (PFS) and overall survival (OS) and were validated in the validation set. The performance of a Cox proportional hazards model with the SPC analysis predictor was assessed with C index and integrated Brier scores (IBS, lower scores indicating higher accuracy) and compared with Cox models based on clinical (age and Karnofsky performance score) and radiologic (Gaussian normalized relative cerebral blood volume and apparent diffusion coefficient) parameters. Results SPC analysis allowed stratification based on 11 features of patients in the discovery set into a low- or high-risk group for PFS (hazard ratio [HR], 2.43; P = .002) and OS (HR, 4.33; P < .001), and the results were validated successfully in the validation set for PFS (HR, 2.28; P = .032) and OS (HR, 3.45; P = .004). The performance of the SPC analysis (OS: IBS, 0.149; C index, 0.654; PFS: IBS, 0.138; C index, 0.611) was higher compared with that of the radiologic (OS: IBS, 0.175; C index, 0