Generation time, net reproductive rate, and growth in stage-age-structured populations

DEFF Research Database (Denmark)

Steiner, Uli; Tuljapurkar, Shripad; Coulson, Tim

2014-01-01

examples to show how reproductive timing Tc and level R0 are shaped by stage dynamics (individual trait changes), selection on the trait, and parent-offspring phenotypic correlation. We also show how population structure can affect dispersion in reproduction among ages and stages. These macroscopic...... to age-structured populations. Here we generalize this result to populations structured by stage and age by providing a new, unique measure of reproductive timing (Tc) that, along with net reproductive rate (R0), has a direct mathematical relationship to and approximates growth rate (r). We use simple...

Genetic and environmental sources of individual differences in views on aging.

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Kornadt, Anna E; Kandler, Christian

2017-06-01

Views on aging are central psychosocial variables in the aging process, but knowledge about their determinants is still fragmental. Thus, the authors investigated the degree to which genetic and environmental factors contribute to individual differences in various domains of views on aging (wisdom, work, fitness, and family), and whether these variance components vary across ages. They analyzed data from 350 monozygotic and 322 dizygotic twin pairs from the Midlife Development in the U.S. (MIDUS) study, aged 25-74. Individual differences in views on aging were mainly due to individual-specific environmental and genetic effects. However, depending on the domain, genetic and environmental contributions to the variance differed. Furthermore, for some domains, variability was larger for older participants; this was attributable to increases in environmental components. This study extends research on genetic and environmental sources of psychosocial variables and stimulates future studies investigating the etiology of views on aging across the life span. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Age differences in the understanding of wealth and power: the mediating role of future time perspective.

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Li, Tianyuan; Tsang, Vivian Hiu-Ling

2016-12-01

Individuals' understanding of wealth and power largely determines their use of resources. Moreover, the age range of wealth and power holders is increasing in modern societies. Thus, the current study examines how people of different ages understand wealth and power. As varying future time perspective is related to changes in prioritised life goals, it was tested as a potential mediator of the age differences. A total of 133 participants aged 18-78 years were asked 8 open-ended questions regarding their understanding of the possible use and desired use of wealth and power, after which they reported their future time perspective. Compared with possible use, the participants mentioned relatively more prosocial elements when they talked about their desired use of the resources, especially power. The older adults expressed more prosocial understanding in regard to the desired use of wealth and the possible use of power compared to their younger counterparts. The age differences were fully mediated by future time perspective. The results suggest that age is a critical factor that influences individuals' conceptualisation of wealth and power. Life-span developmental stage and future time perspective are important factors to consider for explaining individual differences in the exercise of wealth and power and for promoting their prosocial usage.

Time Perspective and Emotion Regulation as Predictors of Age-Related Subjective Passage of Time.

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Wittmann, Marc; Rudolph, Tina; Linares Gutierrez, Damisela; Winkler, Isabell

2015-12-17

Hardly any empirical work exists concerning the relationship between the intra-individually stable time perspective relating to the past, present, and future and the subjective speed of time passing in everyday life. Moreover, studies consistently show that the subjective passage of time over the period of the last ten years speeds up as we get older. Modulating variables influencing this phenomenon are still unknown. To investigate these two unresolved issues, we conducted an online survey with n = 423 participants ranging in age between 17 and 81 assessing trait time perspective of the past, present, and future, and relating these subscales with a battery of measures pertaining to the subjective passage of time. Moreover, the subjective passage of time as an age-dependent variable was probed in relationship to emotion awareness, appraisal and regulation. Results show how present hedonism is linked with having fewer routines in life and a faster passage of the last week; the past negative perspective is related to time pressure, time expansion and more routine; a pronounced future perspective is related to a general faster passage of time. Importantly, increased emotion regulation and a balanced time perspective are related to a slower passage of the last ten years. These novel findings are discussed within models of time perception and the time perspective.

Visual determinants of reduced performance on the Stroop color-word test in normal aging individuals.

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van Boxtel, M P; ten Tusscher, M P; Metsemakers, J F; Willems, B; Jolles, J

2001-10-01

It is unknown to what extent the performance on the Stroop color-word test is affected by reduced visual function in older individuals. We tested the impact of common deficiencies in visual function (reduced distant and close acuity, reduced contrast sensitivity, and color weakness) on Stroop performance among 821 normal individuals aged 53 and older. After adjustment for age, sex, and educational level, low contrast sensitivity was associated with more time needed on card I (word naming), red/green color weakness with slower card 2 performance (color naming), and reduced distant acuity with slower performance on card 3 (interference). Half of the age-related variance in speed performance was shared with visual function. The actual impact of reduced visual function may be underestimated in this study when some of this age-related variance in Stroop performance is mediated by visual function decrements. It is suggested that reduced visual function has differential effects on Stroop performance which need to be accounted for when the Stroop test is used both in research and in clinical settings. Stroop performance measured from older individuals with unknown visual status should be interpreted with caution.

Barriers to participation in physical activity and exercise among middle-aged and elderly individuals.

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Justine, Maria; Azizan, Azliyana; Hassan, Vaharli; Salleh, Zoolfaiz; Manaf, Haidzir

2013-10-01

INTRODUCTION Although the benefits of physical activity and exercise are widely acknowledged, many middle-aged and elderly individuals remain sedentary. This cross-sectional study aimed to identify the external and internal barriers to physical activity and exercise participation among middle-aged and elderly individuals, as well as identify any differences in these barriers between the two groups. METHODS Recruited individuals were categorised into either the middle-aged (age 45-59 years, n = 60) or elderly (age ≥ 60 years, n = 60) group. Data on demographics, anthropometry, as well as external and internal barriers to participation in physical activity and exercise were collected. RESULTS Analysis showed no significant differences in the total scores of all internal barriers between the two groups (p > 0.05). The total scores for most external barriers between the two groups also showed no significant differences (p > 0.05); only 'cost' (p = 0.045) and 'exercise interferes with social/family activities' (p = 0.011) showed significant differences. The most common external barriers among the middle-aged and elderly respondents were 'not enough time' (46.7% vs. 48.4%), 'no one to exercise with' (40.0% vs. 28.3%) and 'lack of facilities' (33.4% vs. 35.0%). The most common internal barriers for middle-aged respondents were 'too tired' (48.3%), 'already active enough' (38.3%), 'do not know how to do it' (36.7%) and 'too lazy' (36.7%), while those for elderly respondents were 'too tired' (51.7%), 'lack of motivation' (38.4%) and 'already active enough' (38.4%). CONCLUSION Middle-aged and elderly respondents presented with similar external and internal barriers to physical activity and exercise participation. These factors should be taken into account when healthcare policies are being designed and when interventions such as the provision of facilities to promote physical activity and exercise among older people are being considered.

Time Perspective and Emotion Regulation as Predictors of Age-Related Subjective Passage of Time

Science.gov (United States)

Wittmann, Marc; Rudolph, Tina; Linares Gutierrez, Damisela; Winkler, Isabell

2015-01-01

Hardly any empirical work exists concerning the relationship between the intra-individually stable time perspective relating to the past, present, and future and the subjective speed of time passing in everyday life. Moreover, studies consistently show that the subjective passage of time over the period of the last ten years speeds up as we get older. Modulating variables influencing this phenomenon are still unknown. To investigate these two unresolved issues, we conducted an online survey with n = 423 participants ranging in age between 17 and 81 assessing trait time perspective of the past, present, and future, and relating these subscales with a battery of measures pertaining to the subjective passage of time. Moreover, the subjective passage of time as an age-dependent variable was probed in relationship to emotion awareness, appraisal and regulation. Results show how present hedonism is linked with having fewer routines in life and a faster passage of the last week; the past negative perspective is related to time pressure, time expansion and more routine; a pronounced future perspective is related to a general faster passage of time. Importantly, increased emotion regulation and a balanced time perspective are related to a slower passage of the last ten years. These novel findings are discussed within models of time perception and the time perspective. PMID:26694439

Time Perspective and Emotion Regulation as Predictors of Age-Related Subjective Passage of Time

Directory of Open Access Journals (Sweden)

Marc Wittmann

2015-12-01

Full Text Available Hardly any empirical work exists concerning the relationship between the intra-individually stable time perspective relating to the past, present, and future and the subjective speed of time passing in everyday life. Moreover, studies consistently show that the subjective passage of time over the period of the last ten years speeds up as we get older. Modulating variables influencing this phenomenon are still unknown. To investigate these two unresolved issues, we conducted an online survey with n = 423 participants ranging in age between 17 and 81 assessing trait time perspective of the past, present, and future, and relating these subscales with a battery of measures pertaining to the subjective passage of time. Moreover, the subjective passage of time as an age-dependent variable was probed in relationship to emotion awareness, appraisal and regulation. Results show how present hedonism is linked with having fewer routines in life and a faster passage of the last week; the past negative perspective is related to time pressure, time expansion and more routine; a pronounced future perspective is related to a general faster passage of time. Importantly, increased emotion regulation and a balanced time perspective are related to a slower passage of the last ten years. These novel findings are discussed within models of time perception and the time perspective.

Beyond chronological age. Examining perceived future time and subjective health as age-related mediators in relation to work-related motivations and well-being

NARCIS (Netherlands)

Kooij, D.T.A.M.; Lange, A.H. de; Jansen, P.G.W.; Dikkers, J.S.E.

2013-01-01

Since workforces across the world are aging, researchers and organizations need more insight into how and why occupational well-being, together with work-related attitudes and motivations, change with age. Lifespan theories point to subjective health and future time perspective (i.e. an individual's

Beyond chronological age : Examining perceived future time and subjective health as age-related mediators in relation to work-related motivations and well-being

NARCIS (Netherlands)

Kooij, T.A.M.; de Lange, A.H.; Jansen, P.G.W.; Dikkers, J.S.E.

2013-01-01

Since workforces across the world are aging, researchers and organizations need more insight into how and why occupational well-being, together with work-related attitudes and motivations, change with age. Lifespan theories point to subjective health and future time perspective (i.e. an individual's

Environmental and Individual Correlates of Various Types of Physical Activity among Community-Dwelling Middle-Aged and Elderly Japanese

Directory of Open Access Journals (Sweden)

Yoshinobu Saito

2013-05-01

Full Text Available Recent studies have suggested the importance of the neighborhood environment in determining the specific type of physical activity. However, few studies on this topic have been undertaken in Japan. This study examined the association of three types of physical activity and their associations with individual and neighborhood environmental factors among middle-aged and elderly Japanese. Participants were 2,449 adults aged 40–69 living in Fujisawa city who had undergone health checkups and responded to our survey by mail. Individual factors, the International Physical Activity Questionnaire (long form, and its environmental module acted as inputs to the study. The adjusted odds ratios (ORs of high levels of moderate-to-vigorous intensity leisure-time physical activity (LTPA, walking for active recreation, and transportation were calculated in relation to individual and neighborhood environmental factors through multiple logistic regression models. Not working and good self-rated health were significantly associated with a higher level of each physical activity outcome. According to the adjusted ORs, higher educational attainment, higher economic status, good access to exercise facilities, and owning motor vehicles were associated with longer LTPA time. However, different sets of factors were associated with longer walking times for recreation and transportation. The results suggest that diverse individual and neighborhood environmental characteristics are associated with different physical activity outcomes. Therefore, customizing environments to become activity-friendly is necessary to increase physical activity effectively among middle-aged and elderly Japanese.

Ageing in individuals with intellectual disability: issues and concerns in Hong Kong.

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Tse, M My; Kwan, R Yc; Lau, J L

2018-02-01

The increasing longevity of people with intellectual disability is testimony to the positive developments occurring in medical intervention. Nonetheless, early-onset age-related issues and concerns cause deterioration of their overall wellbeing. This paper aimed to explore the issues and concerns about individuals with intellectual disability as they age. Articles that discussed people older than 30 years with an intellectual disability and those that identified ageing health issues and concerns were included. Only studies reported in English from 1996 to 2016 were included. We searched PubMed, Google Scholar, and Science Direct using the terms 'intellectual disability', 'ageing', 'cognitive impairment', 'health', and 'screening'. Apart from the early onset of age-related health problems, dementia is more likely to develop by the age of 40 years in individuals with intellectual disability. Geriatric services to people with intellectual disability, however, are only available for those aged 60 years and older. Cognitive instruments used for the general population are not suitable for people with intellectual disability because of floor effects. In Hong Kong, the Chinese version of the Dementia Screening Questionnaire for Individuals with Intellectual Disabilities is the only validated instrument for people with intellectual disability. The use of appropriate measurement tools to monitor the progression of age-related conditions in individuals with intellectual disability is of great value. Longitudinal assessment of cognition and function in people with intellectual disability is vital to enable early detection of significant deterioration. This allows for therapeutic intervention before substantial damage to the brain occurs such as dementia that hastens cognitive and functional decline.

Influence of individual and combined healthy behaviours on successful aging.

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Sabia, Séverine; Singh-Manoux, Archana; Hagger-Johnson, Gareth; Cambois, Emmanuelle; Brunner, Eric J; Kivimaki, Mika

2012-12-11

Increases in life expectancy make it important to remain healthy for as long as possible. Our objective was to examine the extent to which healthy behaviours in midlife, separately and in combination, predict successful aging. We used a prospective cohort design involving 5100 men and women aged 42-63 years. Participants were free of cancer, coronary artery disease and stroke when their health behaviours were assessed in 1991-1994 as part of the Whitehall II study. We defined healthy behaviours as never smoking, moderate alcohol consumption, physical activity (≥ 2.5 h/wk moderate physical activity or ≥ 1 h/wk vigorous physical activity), and eating fruits and vegetables daily. We defined successful aging, measured over a median 16.3-year follow-up, as good cognitive, physical, respiratory and cardiovascular functioning, in addition to the absence of disability, mental health problems and chronic disease (coronary artery disease, stroke, cancer and diabetes). At the end of follow-up, 549 participants had died and 953 qualified as aging successfully. Compared with participants who engaged in no healthy behaviours, participants engaging in all 4 healthy behaviours had 3.3 times greater odds of successful aging (95% confidence interval [CI] 2.1-5.1). The association with successful aging was linear, with the odds ratio (OR) per increment of healthy behaviour being 1.3 (95% CI 1.2-1.4; population-attributable risk for 1-4 v. 0 healthy behaviours 47%). When missing data were considered in the analysis, the results were similar to those of our main analysis. Although individual healthy behaviours are moderately associated with successful aging, their combined impact is substantial. We did not investigate the mechanisms underlying these associations, but we saw clear evidence of the importance of healthy behaviours for successful aging.

Time Perspective and Age: A Review of Age Associated Differences.

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Laureiro-Martinez, Daniella; Trujillo, Carlos A; Unda, Juliana

2017-01-01

We investigate the relationship between age and the five dimensions of time perspective measured by the Zimbardo Time Perspective Inventory (ZTPI) (past negative, past positive, present hedonistic, present fatalistic, and future). Time perspective is related to well-being, decision-making, level of development, and many other psychological issues. Hence, the existence of a systematic relationship between time perspective and age should be considered in all studies for which time is a relevant variable. However, no specific research about this has been conducted. We collected 407 papers that referenced the ZTPI between 2001 and 2015. From those, 72 studies met our inclusion criteria. They included 29,815 participants from 19 countries whose age spans most phases of adulthood (from 13.5 to 75.5 years, mean 28.7). We analyzed these studies adapting meta-analytical techniques. We found that present hedonistic and past negative dimensions are negatively related to aging with partial eta squared effect sizes of roughly 0.15. Our results have implications for the design of studies related to time as our findings highlight the importance of taking into account the differences associated with age.

Impact of aging on neurocognitive performance in previously antiretroviral-naive HIV-infected individuals on their first suppressive regimen.

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Coban, Hamza; Robertson, Kevin; Smurzynski, Marlene; Krishnan, Supriya; Wu, Kunling; Bosch, Ronald J; Collier, Ann C; Ellis, Ronald J

2017-07-17

Despite treatment with virologically suppressive antiretroviral therapy (ART), neurocognitive impairment may persist or develop de novo in aging HIV-infected individuals. We evaluated advancing age as a predictor of neurocognitive impairment in a large cohort of previously ART-naive individuals on long-term ART. The AIDS Clinical Trials Group Longitudinal Linked Randomized Trials was a prospective cohort study of HIV-infected individuals originally enrolled in randomized ART trials. This analysis examined neurocognitive outcomes at least 2 years after ART initiation. All participants underwent annual neurocognitive testing consisting of Trail making A and B, the wechsler adult intelligence scale-revised Digit Symbol and Hopkins Verbal Learning Tests. Uni and multivariable repeated measures regression models evaluated factors associated with neurocognitive performance. Predictors at parent study entry (ART naive) included entry demographics, smoking, injection drug use, hepatitis B surface antigen, hepatitis C virus serostatus, history of stroke, ART regimen type, pre-ART nadir CD4 cell count, and plasma viral load and as well as time-updated plasma viral load and CD4 cell count. The cohort comprised 3313 individuals with median pre-ART age of 38 years, 20% women; 36% Black, non-Hispanic; 22% Hispanic. Virologic suppression was maintained at 91% of follow-up visits. Neurocognitive performance improved with years of ART. After adjusting for the expected effects of age using norms from HIV-negative individuals, the odds of neurocognitive impairment at follow-up visits among the HIV infected increased by nearly 20% for each decade of advancing age. Despite continued virologic suppression and neurocognitive improvement in the cohort as a whole, older individuals were more likely to have neurocognitive impairment than younger individuals.

Brain-Derived Neurotrophic Factor Expression in Individuals With Schizophrenia and Healthy Aging: Testing the Accelerated Aging Hypothesis of Schizophrenia.

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Islam, Farhana; Mulsant, Benoit H; Voineskos, Aristotle N; Rajji, Tarek K

2017-07-01

Schizophrenia has been hypothesized to be a syndrome of accelerated aging. Brain plasticity is vulnerable to the normal aging process and affected in schizophrenia: brain-derived neurotrophic factor (BDNF) is an important neuroplasticity molecule. The present review explores the accelerated aging hypothesis of schizophrenia by comparing changes in BDNF expression in schizophrenia with aging-associated changes. Individuals with schizophrenia show patterns of increased overall mortality, metabolic abnormalities, and cognitive decline normally observed later in life in the healthy population. An overall decrease is observed in BDNF expression in schizophrenia compared to healthy controls and in older individuals compared to a younger cohort. There is a marked decrease in BDNF levels in the frontal regions and in the periphery among older individuals and those with schizophrenia; however, data for BDNF expression in the occipital, parietal, and temporal cortices and the hippocampus is inconclusive. Accelerated aging hypothesis is supported based on frontal regions and peripheral studies; however, further studies are needed in other brain regions.

Effect of age, gender and body mass index on visual and auditory reaction times in Indian population.

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Nikam, Lalita H; Gadkari, Jayshree V

2012-01-01

The effect of Age. Gender and Body Mass Index (BMI) on the Visual (VRT) and Auditory reaction time (ART) was studied in 30 males and 30 females in the age group of 18-20 years along with 30 males and 30 females in the age group of 65-75 years. Statistical analysis of the data by one-way ANOVA and post-hoc by Tukey-HSD test showed that BMI, VRT and ART were significantly higher in old than young individuals. Females had higher BMI and longer reaction times than males. There was significant positive correlation between BMI and reaction times (VRT and ART) in both males and females by Pearson correlation analysis. Older individuals should be more careful and vigilant about the injuries and falls due to increased reaction time. Longer reaction times and higher BMI in females could be attributed to fluid and salt retention due to female sex hormones affecting sensorimotor co-ordination.

Aging and Variability of Individual Differences: A Longitudinal Analysis of Social, Psychological, and Physiological Indicators.

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Maddox, George L.; Douglass, Elizabeth B.

This paper explores the relationship between age and individual differences. Two hypotheses were tested through the use of repeated measures of functioning in terms of social, psychological, and physiological parameters: (1) individual differences do not decrease with age, and (2) individuals tend to maintain the same rank in relation to age peers…

Factors affecting red blood cell storage age at the time of transfusion.

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Dzik, Walter H; Beckman, Neil; Murphy, Michael F; Delaney, Meghan; Flanagan, Peter; Fung, Mark; Germain, Marc; Haspel, Richard L; Lozano, Miguel; Sacher, Ronald; Szczepiorkowski, Zbigniew; Wendel, Silvano

2013-12-01

Clinical trials are investigating the potential benefit resulting from a reduced maximum storage interval for red blood cells (RBCs). The key drivers that determine RBC age at the time of issue vary among individual hospitals. Although progressive reduction in the maximum storage period of RBCs would be expected to result in smaller hospital inventories and reduced blood availability, the magnitude of the effect is unknown. Data on current hospital blood inventories were collected from 11 hospitals and three blood centers in five nations. A general predictive model for the age of RBCs at the time of issue was developed based on considerations of demand for RBCs in the hospital. Age of RBCs at issue is sensitive to the following factors: ABO group, storage age at the time of receipt by the hospital, the restock interval, inventory reserve, mean demand, and variation in demand. A simple model, based on hospital demand, may serve as the basis for examining factors affecting the storage age of RBCs in hospital inventories. The model suggests that the age of RBCs at the time of their issue to the patient depends on factors external to the hospital transfusion service. Any substantial change in the expiration date of stored RBCs will need to address the broad variation in demand for RBCs while attempting to balance considerations of availability and blood wastage. © 2013 American Association of Blood Banks.

Individual differences in long-range time representation.

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Agostino, Camila S; Caetano, Marcelo S; Balci, Fuat; Claessens, Peter M E; Zana, Yossi

2017-04-01

On the basis of experimental data, long-range time representation has been proposed to follow a highly compressed power function, which has been hypothesized to explain the time inconsistency found in financial discount rate preferences. The aim of this study was to evaluate how well linear and power function models explain empirical data from individual participants tested in different procedural settings. The line paradigm was used in five different procedural variations with 35 adult participants. Data aggregated over the participants showed that fitted linear functions explained more than 98% of the variance in all procedures. A linear regression fit also outperformed a power model fit for the aggregated data. An individual-participant-based analysis showed better fits of a linear model to the data of 14 participants; better fits of a power function with an exponent β > 1 to the data of 12 participants; and better fits of a power function with β discount rates in intertemporal choice to the compressed nature of subjective time must entail the characterization of subjective time on an individual-participant basis.

Time trends in heavy drinking among middle-aged and older adults in Denmark

DEFF Research Database (Denmark)

Bjørk, Christina; Thygesen, Lau Caspar; Vinther-Larsen, Mathilde

2008-01-01

BACKGROUND: Studies have indicated an increasing proportion of heavy drinking among middle-aged and older Danes. Trends in consumption are often extremely sensitive to influence from various components of the time trends but only few have explored the age, period and cohort-related influences...... that the proportion of heavy drinking women increases in younger birth cohorts. This trend is not observed for men as their drinking pattern mainly increase slightly by calendar year. CONCLUSIONS: Our Danish observations for older aged individuals correspond to the social and cultural changes in the 1960s and 1970s...

Individuation in Quantum Mechanics and Space-Time

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Jaeger, Gregg

2010-10-01

Two physical approaches—as distinct, under the classification of Mittelstaedt, from formal approaches—to the problem of individuation of quantum objects are considered, one formulated in spatiotemporal terms and one in quantum mechanical terms. The spatiotemporal approach itself has two forms: one attributed to Einstein and based on the ontology of space-time points, and the other proposed by Howard and based on intersections of world lines. The quantum mechanical approach is also provided here in two forms, one based on interference and another based on a new Quantum Principle of Individuation (QPI). It is argued that the space-time approach to individuation fails and that the quantum approach offers several advantages over it, including consistency with Leibniz’s Principle of Identity of Indiscernibles.

Real-time individualization of the unified model of performance.

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Liu, Jianbo; Ramakrishnan, Sridhar; Laxminarayan, Srinivas; Balkin, Thomas J; Reifman, Jaques

2017-12-01

Existing mathematical models for predicting neurobehavioural performance are not suited for mobile computing platforms because they cannot adapt model parameters automatically in real time to reflect individual differences in the effects of sleep loss. We used an extended Kalman filter to develop a computationally efficient algorithm that continually adapts the parameters of the recently developed Unified Model of Performance (UMP) to an individual. The algorithm accomplishes this in real time as new performance data for the individual become available. We assessed the algorithm's performance by simulating real-time model individualization for 18 subjects subjected to 64 h of total sleep deprivation (TSD) and 7 days of chronic sleep restriction (CSR) with 3 h of time in bed per night, using psychomotor vigilance task (PVT) data collected every 2 h during wakefulness. This UMP individualization process produced parameter estimates that progressively approached the solution produced by a post-hoc fitting of model parameters using all data. The minimum number of PVT measurements needed to individualize the model parameters depended upon the type of sleep-loss challenge, with ~30 required for TSD and ~70 for CSR. However, model individualization depended upon the overall duration of data collection, yielding increasingly accurate model parameters with greater number of days. Interestingly, reducing the PVT sampling frequency by a factor of two did not notably hamper model individualization. The proposed algorithm facilitates real-time learning of an individual's trait-like responses to sleep loss and enables the development of individualized performance prediction models for use in a mobile computing platform. © 2017 European Sleep Research Society.

Linking age, survival, and transit time distributions

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Calabrese, Salvatore; Porporato, Amilcare

2015-10-01

Although the concepts of age, survival, and transit time have been widely used in many fields, including population dynamics, chemical engineering, and hydrology, a comprehensive mathematical framework is still missing. Here we discuss several relationships among these quantities by starting from the evolution equation for the joint distribution of age and survival, from which the equations for age and survival time readily follow. It also becomes apparent how the statistical dependence between age and survival is directly related to either the age dependence of the loss function or the survival-time dependence of the input function. The solution of the joint distribution equation also allows us to obtain the relationships between the age at exit (or death) and the survival time at input (or birth), as well as to stress the symmetries of the various distributions under time reversal. The transit time is then obtained as a sum of the age and survival time, and its properties are discussed along with the general relationships between their mean values. The special case of steady state case is analyzed in detail. Some examples, inspired by hydrologic applications, are presented to illustrate the theory with the specific results. This article was corrected on 11 Nov 2015. See the end of the full text for details.

Relative Age in School and Suicide among Young Individuals in Japan: A Regression Discontinuity Approach.

Directory of Open Access Journals (Sweden)

Tetsuya Matsubayashi

Full Text Available Evidence collected in many parts of the world suggests that, compared to older students, students who are relatively younger at school entry tend to have worse academic performance and lower levels of income. This study examined how relative age in a grade affects suicide rates of adolescents and young adults between 15 and 25 years of age using data from Japan.We examined individual death records in the Vital Statistics of Japan from 1989 to 2010. In contrast to other countries, late entry to primary school is not allowed in Japan. We took advantage of the school entry cutoff date to implement a regression discontinuity (RD design, assuming that the timing of births around the school entry cutoff date was randomly determined and therefore that individuals who were born just before and after the cutoff date have similar baseline characteristics.We found that those who were born right before the school cutoff day and thus youngest in their cohort have higher mortality rates by suicide, compared to their peers who were born right after the cutoff date and thus older. We also found that those with relative age disadvantage tend to follow a different career path than those with relative age advantage, which may explain their higher suicide mortality rates.Relative age effects have broader consequences than was previously supposed. This study suggests that policy intervention that alleviates the relative age effect can be important.

Similarity estimators for irregular and age uncertain time series

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Rehfeld, K.; Kurths, J.

2013-09-01

Paleoclimate time series are often irregularly sampled and age uncertain, which is an important technical challenge to overcome for successful reconstruction of past climate variability and dynamics. Visual comparison and interpolation-based linear correlation approaches have been used to infer dependencies from such proxy time series. While the first is subjective, not measurable and not suitable for the comparison of many datasets at a time, the latter introduces interpolation bias, and both face difficulties if the underlying dependencies are nonlinear. In this paper we investigate similarity estimators that could be suitable for the quantitative investigation of dependencies in irregular and age uncertain time series. We compare the Gaussian-kernel based cross correlation (gXCF, Rehfeld et al., 2011) and mutual information (gMI, Rehfeld et al., 2013) against their interpolation-based counterparts and the new event synchronization function (ESF). We test the efficiency of the methods in estimating coupling strength and coupling lag numerically, using ensembles of synthetic stalagmites with short, autocorrelated, linear and nonlinearly coupled proxy time series, and in the application to real stalagmite time series. In the linear test case coupling strength increases are identified consistently for all estimators, while in the nonlinear test case the correlation-based approaches fail. The lag at which the time series are coupled is identified correctly as the maximum of the similarity functions in around 60-55% (in the linear case) to 53-42% (for the nonlinear processes) of the cases when the dating of the synthetic stalagmite is perfectly precise. If the age uncertainty increases beyond 5% of the time series length, however, the true coupling lag is not identified more often than the others for which the similarity function was estimated. Age uncertainty contributes up to half of the uncertainty in the similarity estimation process. Time series irregularity

Similarity estimators for irregular and age-uncertain time series

Science.gov (United States)

Rehfeld, K.; Kurths, J.

2014-01-01

Paleoclimate time series are often irregularly sampled and age uncertain, which is an important technical challenge to overcome for successful reconstruction of past climate variability and dynamics. Visual comparison and interpolation-based linear correlation approaches have been used to infer dependencies from such proxy time series. While the first is subjective, not measurable and not suitable for the comparison of many data sets at a time, the latter introduces interpolation bias, and both face difficulties if the underlying dependencies are nonlinear. In this paper we investigate similarity estimators that could be suitable for the quantitative investigation of dependencies in irregular and age-uncertain time series. We compare the Gaussian-kernel-based cross-correlation (gXCF, Rehfeld et al., 2011) and mutual information (gMI, Rehfeld et al., 2013) against their interpolation-based counterparts and the new event synchronization function (ESF). We test the efficiency of the methods in estimating coupling strength and coupling lag numerically, using ensembles of synthetic stalagmites with short, autocorrelated, linear and nonlinearly coupled proxy time series, and in the application to real stalagmite time series. In the linear test case, coupling strength increases are identified consistently for all estimators, while in the nonlinear test case the correlation-based approaches fail. The lag at which the time series are coupled is identified correctly as the maximum of the similarity functions in around 60-55% (in the linear case) to 53-42% (for the nonlinear processes) of the cases when the dating of the synthetic stalagmite is perfectly precise. If the age uncertainty increases beyond 5% of the time series length, however, the true coupling lag is not identified more often than the others for which the similarity function was estimated. Age uncertainty contributes up to half of the uncertainty in the similarity estimation process. Time series irregularity

Age-related hearing decline in individuals with and without occupational noise exposure

Directory of Open Access Journals (Sweden)

Christina Hederstierna

2016-01-01

Full Text Available This study was conducted to compare the pattern of age-related hearing decline in individuals with and without self-reported previous occupational noise exposure. This was a prospective, population-based, longitudinal study of individuals aged 70-75 years, from an epidemiological investigation, comprising three age cohorts. In total there were 1013 subjects (432 men and 581 women. Participants were tested with pure tone audiometry, and they answered a questionnaire to provide information regarding number of years of occupational noise exposure. There were no significant differences in hearing decline, at any frequency, for those aged 70-75 years between the noise-exposed (N= 62 men, 22 women and the nonexposed groups (N = 96 men, 158 women. This study supports the additive model of noise-induced hearing loss (NIHL and age-related hearing loss (ARHL. The concept of different patterns of hearing decline between persons exposed and not exposed to noise could not be verified.

Age estimation of living Indian individuals based on aspartic acid racemization from tooth biopsy specimen

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Rastogi, Manu; Logani, Ajay; Shah, Naseem; Kumar, Abhishek; Arora, Saurabh

2017-01-01

Background: Age estimation in living individuals is imperative to amicably settle civil and criminal disputes. A biochemical method based on amino acid racemization was evaluated for age estimation of living Indian individuals. Design: Caries-free maxillary/mandibular premolar teeth (n = 90) were collected from participants with age proof documents and divided into predefined nine age groups. Materials and Methods: Dentine biopsy from the labial aspect of the tooth crown was taken with an indigenously developed microtrephine. The samples were processed and subjected to gas chromatography. Dextrorotatory:levorotatory ratios were calculated, and a regression equation was formulated. Results: Across all age groups, an error of 0 ± 4 years between protein racemization age and chronological age was observed. Conclusion: Aspartic acid racemization from dentine biopsy samples could be a viable and accurate technique for age estimation of living individuals who have attained a state of skeletal maturity. PMID:29263613

Aging in a Relativistic Biological Space-Time

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Davide Maestrini

2018-05-01

Full Text Available Here we present a theoretical and mathematical perspective on the process of aging. We extend the concepts of physical space and time to an abstract, mathematically-defined space, which we associate with a concept of “biological space-time” in which biological dynamics may be represented. We hypothesize that biological dynamics, represented as trajectories in biological space-time, may be used to model and study different rates of biological aging. As a consequence of this hypothesis, we show how dilation or contraction of time analogous to relativistic corrections of physical time resulting from accelerated or decelerated biological dynamics may be used to study precipitous or protracted aging. We show specific examples of how these principles may be used to model different rates of aging, with an emphasis on cancer in aging. We discuss how this theory may be tested or falsified, as well as novel concepts and implications of this theory that may improve our interpretation of biological aging.

Time perspective and exercise, obesity, and smoking: moderation of associations by age.

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Guthrie, Lori C; Butler, Stephen C; Lessl, Kristen; Ochi, Onyinyechukwu; Ward, Michael M

2014-01-01

Time perspective, a psychological construct denoting subjective orientation to either present or future concerns, has been inconsistently associated with healthy behaviors in adults. We hypothesized that associations would be stronger in young adults, who are first developing independent attitudes, than in older adults. Cross-sectional survey. The study was conducted in three cities in the Mid-Atlantic region. Subjects were 790 patrons of barber and beauty shops. Measures used were the Zimbardo Time Perspective Inventory future, present-fatalistic, and present-hedonistic subscales and current smoking, days per week of recreational exercise, and height and weight, by self-report. We tested if associations between time perspective and exercise, obesity, and current smoking differed by age group (18-24 years, 25-34 years, and 35 years and older) using analysis of variance and logistic regression. Higher future time perspective scores, indicating greater focus on future events, was associated with more frequent exercise, whereas higher present-fatalistic time perspective scores, indicating more hopelessness, was associated with less frequent exercise in 18- to 24-year-olds, but not in older individuals. Lower future time perspective scores, and higher present-hedonistic time perspective scores, indicating interest in pleasure-seeking, were also associated with obesity only in 18- to 24-year-olds. Current smoking was not related to time perspective in any age group. Time perspective has age-specific associations with exercise and obesity, suggesting stages when time perspective may influence health behavior decision making.

Diet quality is associated with leisure-time physical activity in individuals at cardiometabolic risk.

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Monfort-Pires, Milena; Salvador, Emanuel P; Folchetti, Luciana D; Siqueira-Catania, Antonela; Barros, Camila R; Ferreira, Sandra Roberta Gouvea

2014-01-01

We investigated whether diet quality was associated with leisure-time physical activity (LTPA) and television viewing and the associations of these variables with traditional cardiovascular risk factors and novel biomarkers in individuals at cardiometabolic risk. A total of 193 prediabetic adults (63.7% women, mean age 54.1 years), screened for a diabetes prevention program in Brazil, participated in this cross-sectional study. Clinical data and blood samples were collected for several determinations. Twenty-four-hour recalls were used to calculate the Healthy Eating Index (HEI) adapted to Brazilian dietary habits and the International Physical Activity Questionnaire to assess physical activity level. Analysis of covariance with adjustments for age and body mass index (BMI) was employed to test associations across categories of LTPA and television viewing. Stratifying according to LTPA categories, the most active subset (≥150 minutes/week) showed better HEI scores after adjustments (64.6 ± 11.0, 65.1 ± 10.3, and 68.6 ± 10.8, p = 0.02) and significant higher values of dark green and orange vegetables but not of whole grains (p = 0.06). Active individuals had lower BMI, waist circumference, inflammatory markers, and better insulin sensitivity (p physical activity [PA]), with those with unhealthy habits revealing better anthropometric and cardiometabolic profiles in the former group. Diet quality assessed by the HEI adapted for Brazilian eating habits attained significance in differentiating more active from inactive at-risk individuals during leisure time. Time watching television, as a surrogate of sedentary behavior, is not useful to detect unhealthy diet quality. LTPA is indicative of better cardiometabolic profile reflected by lipid and inflammatory markers and index of insulin resistance.

Continuous time modelling with individually varying time intervals for oscillating and non-oscillating processes.

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Voelkle, Manuel C; Oud, Johan H L

2013-02-01

When designing longitudinal studies, researchers often aim at equal intervals. In practice, however, this goal is hardly ever met, with different time intervals between assessment waves and different time intervals between individuals being more the rule than the exception. One of the reasons for the introduction of continuous time models by means of structural equation modelling has been to deal with irregularly spaced assessment waves (e.g., Oud & Delsing, 2010). In the present paper we extend the approach to individually varying time intervals for oscillating and non-oscillating processes. In addition, we show not only that equal intervals are unnecessary but also that it can be advantageous to use unequal sampling intervals, in particular when the sampling rate is low. Two examples are provided to support our arguments. In the first example we compare a continuous time model of a bivariate coupled process with varying time intervals to a standard discrete time model to illustrate the importance of accounting for the exact time intervals. In the second example the effect of different sampling intervals on estimating a damped linear oscillator is investigated by means of a Monte Carlo simulation. We conclude that it is important to account for individually varying time intervals, and encourage researchers to conceive of longitudinal studies with different time intervals within and between individuals as an opportunity rather than a problem. © 2012 The British Psychological Society.

Age of majority assessment in Dutch individuals based on Cameriere's third molar maturity index.

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Boyacıoğlu Doğru, Hatice; Gulsahi, Ayşe; Çehreli, Sevi Burçak; Galić, Ivan; van der Stelt, Paul; Cameriere, Roberto

2018-01-01

Radiological examination of the third molar is done in living individuals for estimation of chronological age, especially in the late adolescence. The aim of this study was to assess the application of Cameriere's third molar maturity index (I 3M ) to determine whether an individual is 18 years or older (adult) or younger than 18 years (minor) in a sample of Dutch individuals. The sample consisted of panoramic images of 360 individuals aged between 14 and 22 years old. Three observers performed the measurements. Gender was not statistically significant in discriminating adults and minors. The highest value of the Youden index of the receiver operating curve analysis was for the value of I 3M age assessment in a Dutch population. Copyright © 2017 Elsevier B.V. All rights reserved.

Age-related differences in foot mobility in individuals with patellofemoral pain.

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Tan, Jade M; Crossley, Kay M; Vicenzino, Bill; Menz, Hylton B; Munteanu, Shannon E; Collins, Natalie J

2018-01-01

Age-related changes in midfoot mobility have the potential to influence success with foot orthoses intervention in people with patellofemoral pain (PFP). The aim of this study was to determine whether older people with PFP demonstrate less foot mobility than younger adults with PFP. One hundred ninety four participants (113 (58%) women, age 32 ± 7 years, BMI 25 ± 4.9 kg/m 2 ) with PFP (≥ 6 weeks duration) were included, with foot mobility quantified using reliable and valid methods. K-means cluster analysis classified participants into three homogenous groups based on age. After cluster formation, univariate analyses of co-variance (covariates: sex, weight) were used to compare midfoot height mobility, midfoot width mobility, and foot mobility magnitude between age groups (significance level 0.05). Cluster analysis revealed three distinct age groups: 18-29 years ( n  = 70); 30-39 years ( n  = 101); and 40-50 years ( n  = 23). There was a significant main effect for age for midfoot height mobility ( p  mobility magnitude ( p  = 0.006). Post-hoc analyses revealed that midfoot height mobility differed across all three groups (moderate to large effect sizes), and that foot mobility magnitude was significantly less in those aged 40-50 years compared to those aged 18-25 years (moderate effect size). There were no significant main effects for age for midfoot width mobility ( p  > 0.05). Individuals with PFP aged 40-50 years have less foot mobility than younger adults with PFP. These findings may have implications for evaluation and treatment of older individuals with PFP.

Individual and family environmental correlates of television and computer time in 10- to 12-year-old European children: the ENERGY-project.

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Verloigne, Maïté; Van Lippevelde, Wendy; Bere, Elling; Manios, Yannis; Kovács, Éva; Grillenberger, Monika; Maes, Lea; Brug, Johannes; De Bourdeaudhuij, Ilse

2015-09-18

The aim was to investigate which individual and family environmental factors are related to television and computer time separately in 10- to-12-year-old children within and across five European countries (Belgium, Germany, Greece, Hungary, Norway). Data were used from the ENERGY-project. Children and one of their parents completed a questionnaire, including questions on screen time behaviours and related individual and family environmental factors. Family environmental factors included social, political, economic and physical environmental factors. Complete data were obtained from 2022 child-parent dyads (53.8 % girls, mean child age 11.2 ± 0.8 years; mean parental age 40.5 ± 5.1 years). To examine the association between individual and family environmental factors (i.e. independent variables) and television/computer time (i.e. dependent variables) in each country, multilevel regression analyses were performed using MLwiN 2.22, adjusting for children's sex and age. In all countries, children reported more television and/or computer time, if children and their parents thought that the maximum recommended level for watching television and/or using the computer was higher and if children had a higher preference for television watching and/or computer use and a lower self-efficacy to control television watching and/or computer use. Most physical and economic environmental variables were not significantly associated with television or computer time. Slightly more individual factors were related to children's computer time and more parental social environmental factors to children's television time. We also found different correlates across countries: parental co-participation in television watching was significantly positively associated with children's television time in all countries, except for Greece. A higher level of parental television and computer time was only associated with a higher level of children's television and computer time in Hungary. Having rules

Assessment of retinal sensitivity using a time-saving strategy in normal individuals

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Suzumura H

2012-11-01

Full Text Available Hirotaka Suzumura,1 Keiji Yoshikawa,2 Shiro Mizoue,3 Ryoko Hyodo,4 Tairo Kimura5 1Eye Department, Nakano General Hospital, Tokyo, 2Yoshikawa Eye Clinic, Tokyo, 3Department of Ophthalmology, Ehime University, Ehime, 4Eye Department, Minami Matsuyama Hospital, Ehime, 5Ueno Eye Clinic, Tokyo, JapanBackground: The purpose of this study was to compare retinal sensitivities in normal individuals obtained using the Swedish Interactive Threshold Algorithm Standard (SITA-S on the Humphrey field analyzer with those obtained using the Dynamic strategy on the Octopus.Methods: Prior to visual field examinations, the background luminance, stimulus size, and exposure time with the Octopus 101 were conformed to the Humphrey field analyzer II settings. Volunteers over 20 years of age without apparent ophthalmic abnormalities were examined with the SITA-S central 30-2 program followed by the Dynamic 32 program. Eye with corrected visual acuity ≥0.8, refraction ≥ −6.0 diopters, and fields with satisfactory levels of reliability in SITA-S and Dynamic were selected.Results: Sixty-seven eyes from 67 normal individuals of mean age 51.3 ± 16.3 (range 22–76 years satisfied the selection criteria and were analyzed. Mean retinal sensitivity was significantly (P < 0.0001 higher with SITA-S (29.0 ± 2.4 dB than with Dynamic (26.8 ± 2.1 dB. Changes in retinal sensitivity with increasing age were significantly (P = 0.0003 greater with Dynamic (−0.09 ± 0.04 dB/year; 95% confidence interval [CI] −0.10 to −0.08 dB/year than with SITA-S (−0.07 ± 0.04 dB/year, 95% CI −0.08 to −0.06 dB/year. When classifying the visual field into three areas (central, mid-peripheral, and peripheral, retinal sensitivities with SITA-S were significantly higher in all areas than with Dynamic (P < 0.0001 for all three areas.Conclusion: Differences in Dynamic and SITA-S strategies may contribute to the differences in retinal sensitivities observed in normal individuals

42 CFR 440.160 - Inpatient psychiatric services for individuals under age 21.

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2010-10-01

... 42 Public Health 4 2010-10-01 2010-10-01 false Inpatient psychiatric services for individuals... Definitions § 440.160 Inpatient psychiatric services for individuals under age 21. “Inpatient psychiatric... physician; (b) Are provided by— (1) A psychiatric hospital that undergoes a State survey to determine...

Estimation of legal age using calcification stages of third molars in living individuals.

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Streckbein, Philipp; Reichert, Isabelle; Verhoff, Marcel A; Bödeker, Rolf-Hasso; Kähling, Christopher; Wilbrand, Jan-Falco; Schaaf, Heidrun; Howaldt, Hans-Peter; May, Andreas

2014-12-01

The increased number of adolescents and young adults with unknown or inaccurately given date of birth is a current issue in justice and legal medicine. The objective of this study was to determine the extent to which third molar calcification stages assessed on panoramic X-rays could be useful as additional criteria for forensic age estimation in living individuals, focusing on the legally important ages 17 and 18. In a retrospective multi-center study, the developmental stage of each individual's third molar was analyzed using Demirjian's scale in 2360 cases. Additionally, sex, age and ancestry were assessed. Individuals with the lowest calcification stage of all present molars in stage H were ≥18 years with a likelihood of ≥99.05% in the female (n=388), and ≥99.24% in the male (n=482) population. The lowest calcification stage of all present third molars proved to be useful as an additional reliable criterion for the determination of an age ≥18 years. Copyright © 2014 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

Optimization of the wearing time for passive individual dosimeters

International Nuclear Information System (INIS)

Aleinikov, V.E.; )

1998-01-01

A cost-benefit equation was derived for the optimum wearing time of passive individual dosemeters. This equation was applied to the long-normal distribution of occupational individual doses. A plot of the optimum wearing time in dependence on the lower detection limit is reproduced. It is shown that the optimum wearing time depends on the dose distribution as well as on the quotient of the cost assigned to the unit collective dose, α, the cost of the dosemeter, C, and the lower detection limit, D. If the C/α ratio is infinitesimal, the optimum wearing time is directly proportional to the square root of the DL product (L is the dose limit) and inversely proportional to the average annual individual dose for the log-normal distribution. (P.A.)

Prevalence and factors associated with dental erosion in individuals aged 12-30 years in a northeastern Brazilian city.

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Luciano, Luanda Cristina O; Ferreira, Meire Coelho; Paschoal, Marco Aurelio

2017-01-01

Dental erosion in young individuals has increased significantly in recent years, due to changes in lifestyle. Thus, the present study investigated the prevalence and factors associated with dental erosion in individuals aged 12-30 years in the city of Imperatriz of Maranhão, Brazil. A cross-sectional study was conducted on 335 individuals who answered a questionnaire consisting of variables related to dental erosion. Afterwards, the individuals were subjected to clinical examinations and the basic erosive wear examination index was used to classify their teeth according to the presence and severity of dental erosion. Descriptive statistics, the chi-square test, Poisson univariate and multivariate regression were performed at 5% level of significance. The sample was characterized by 204 females (60.9%), the majority of whom were from 12 to 19 years of age (78.5%), among whom 28.7% presented dental erosion. Their monthly family income was from 1 to 3 minimum wages (56.4%). The variables that were significantly associated with the outcome were family income, chewing gum, and consumption of soft-drinks/juices before going to sleep ( p =0.03, p =0.001, and p =0.04, respectively). Individuals who chewed chewing gum were 2.27 times (95% CI =1.43-3.60) more likely to present dental erosion than those who did not chew gum. Individuals who ingested soft drinks or juices were 2.30 times (95% CI =1.30-4.10) more likely to present dental erosion. The prevalence of erosion reflected the need for programs of prevention and guidance for patients about the etiological factors of the disease.

Association of insufficient physical activity with sarcopenia and sarcopenic obesity in individuals aged 50 years or more

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Vanessa Ribeiro dos SANTOS

Full Text Available ABSTRACT Objective: To analyze the association of insufficient physical activity in different domains with sarcopenia or sarcopenic obesity in patients aged ³50 years. Methods: The sample consisted of 770 males and females. Sarcopenia was diagnosed when the individual had: (1 low muscle mass and muscle strength; or (2 low walking speed and low muscle mass; sarcopenic obesity was diagnosed when individuals were at risk of obesity and sarcopenia. Muscle mass was given by a predictive equation, and then the muscle mass index (in kg/m² was given by muscle mass divided by height squared. Muscle strength, in kg, was given by measuring handgrip strength with a digital dynamometer. The 4m walk test evaluated walking sped. Low muscle mass, muscle strength, and walking speed were defined as the respective values below the 25th percentile, and risk of obesity was defined as body mass index ³25kg/m2. Results: Habitual physical activity was investigated by a questionnaire. Insufficient leisure-time physical activity was associated with sarcopenia (OR=2.55; 95%CI=1.10-5.88. In addition, insufficient leisure-time physical activity (OR=4.75; 95%CI=1.64-13.72, leisure-time and commuting physical activities (OR=2.49; 95%CI=1.02-6.11, and habitual physical activity (OR=3.55; 95%CI=1.0-11.79 were associated with sarcopenic obesity. Conclusion: Insufficient physical activity is associated with sarcopenia or sarcopenic obesity in the study individuals aged ³50years.

Assessment of bruise age on dark-skinned individuals using tristimulus colorimetry.

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Thavarajah, D; Vanezis, P; Perrett, D

2012-01-01

Studies on the ageing of bruises have been reported on Caucasians or individuals of fair ethnicity. This study focuses on bruise changes in dark-skinned individuals using tristimulus colorimetry for forensic analysis in such individuals. Eighteen subjects of South Indian or Sri-Lankan ethnicity were recruited. Subjects were bruised using a vacuum pump and then daily colour measurements were taken of the bruise using a tristimulus colorimeter. The L*a*b* readings were recorded of a control area and of the bruise until it disappeared. Two Caucasians were used for comparison. This study showed that, using colorimetry, bruises on dark-skinned individuals can be measured and analysed even if the bruises are unclear visually. As the bruise is beneath the skin, the colour difference ΔL*, Δa* and Δb* were calculated. All values showed a trend, indicating that the L*a*b* measuring technique is a reliable method to analyse bruises on dark-skinned individuals. Comparisons of Asian subjects and Caucasian subjects were performed. The largest difference was seen in the b* value. Statistical analysis showed that ΔL* colour difference was the most consistent (95% CI -4.05 to -2.49) showing a significant difference between days 1-4 and 5-8. Objective assessment of bruises on dark-skinned individuals using the L*a*b* method of measuring gave reproducible results. Furthermore, the study showed that the yellowing of a bruise cannot be seen or measured with a tristimulus colorimeter on dark-skinned individuals due to the pigmentation of the skin. With further studies and more subjects, the age of bruises could potentially be assessed for use in forensic analysis.

Individual Differences in Recovery Time From Attentional Capture

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Fukuda, Keisuke; Vogel, Edward K.

2015-01-01

Working memory capacity reflects a core ability of the individual that affects performance on many cognitive tasks. Recent work has suggested that an important covariate of memory capacity is attentional control, and specifically that low-capacity individuals are more susceptible to attentional capture by distractors than high-capacity individuals are, with the latter being able to resist capture. Here, we tested an alternative account according to which all individuals are equally susceptible to attentional capture, but high-capacity individuals recover more quickly than low-capacity individuals. Using psychophysical and electrophysiological methods, we measured recovery time from attentional capture. In two experiments, we found that high- and low-capacity individuals showed equivalent attentional capture effects in the initial moments following capture, but that low-capacity individuals took much longer to recover than high-capacity individuals did. These results suggest that the poor attentional control associated with low capacity is due to slow disengagement from distractors. PMID:21310945

Timing of initial arrival at the breeding site predicts age at first reproduction in a long-lived migratory bird

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Becker, Peter H.; Dittmann, Tobias; Ludwigs, Jan-Dieter; Limmer, Bente; Ludwig, Sonja C.; Bauch, Christina; Braasch, Alexander; Wendeln, Helmut

2008-01-01

In long-lived vertebrates, individuals generally visit potential breeding areas or populations during one or more seasons before reproducing for the first time. During these years of prospecting, they select a future breeding site, colony, or mate and improve various skills and their physical condition to meet the requirements of reproduction. One precondition of successful reproduction is arrival in time on the breeding grounds. Here, we study the intricate links among the date of initial spring arrival, body mass, sex, and the age of first breeding in the common tern Sterna hirundo, a long-lived migratory colonial seabird. The study is based on a unique, individual-based, long-term dataset of sexed birds, marked with transponders, which allow recording their individual arrival, overall attendance, and clutch initiation remotely and automatically year by year over the entire lifetime at the natal colony site. We show that the seasonal date of initial arrival at the breeding grounds predicts the individual age at first reproduction, which mostly occurs years later. Late first-time arrivals remain delayed birds throughout subsequent years. Our findings reveal that timing of arrival at the site of reproduction and timing of reproduction itself are coherent parameters of individual quality, which are linked with the prospects of the breeding career and may have consequences for fitness. PMID:18711134

Anatomical brain difference of subthreshold depression in young and middle-aged individuals.

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Li, Jing; Wang, Zengjian; Hwang, JiWon; Zhao, Bingcong; Yang, Xinjing; Xin, Suicheng; Wang, Yu; Jiang, Huili; Shi, Peng; Zhang, Ye; Wang, Xu; Lang, Courtney; Park, Joel; Bao, Tuya; Kong, Jian

2017-01-01

Subthreshold depression (StD) is associated with substantial functional impairments due to depressive symptoms that do not fully meet the diagnosis of major depressive disorder (MDD). Its high incidence in the general population and debilitating symptoms has recently put it at the forefront of mood disorder research. In this study we investigated common volumetric brain changes in both young and middle-aged StD patients. Two cohorts of StD patients, young and middle-aged, ( n  = 57) and matched controls ( n  = 76) underwent voxel-based morphometry (VBM). VBM analysis found that: 1) compared with healthy controls, StD patients showed decreased gray matter volume (GMV) in the bilateral globus pallidus and precentral gyrus, as well as increased GMV in the left thalamus and right rostral anterior cingulate cortex/medial prefrontal cortex; 2) there is a significant association between Center for Epidemiological Studies Depression Scale scores and the bilateral globus pallidus (negative) and left thalamus (positive); 3) there is no interaction between age (young vs. middle-age) and group (StD vs. controls). Our findings indicate significant VBM brain changes in both young and middle-aged individuals with StD. Individuals with StD, regardless of age, may share common neural characteristics.

Subjective Age in Early Adolescence: Relationships with Chronological Age, Pubertal Timing, Desired Age, and Problem Behaviors

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Hubley, Anita M.; Arim, Rubab G.

2012-01-01

Subjective age generally refers to the age that one feels. In a cross-sectional questionnaire study of 245 adolescents ages 10-14 years, we examined (a) whether, and when, a cross-over in subjective age occurs, (b) differences in subjective age among pubertal timing groups, (c) correlations between subjective age and each of desired age and five…

42 CFR 435.230 - Aged, blind, and disabled individuals in States that use more restrictive requirements for...

Science.gov (United States)

2010-10-01

... 42 Public Health 4 2010-10-01 2010-10-01 false Aged, blind, and disabled individuals in States... Coverage of the Aged, Blind, and Disabled § 435.230 Aged, blind, and disabled individuals in States that... for aged, blind, and disabled SSI recipients using more restrictive requirements than those used under...

Forensic individual age estimation with DNA: From initial approaches to methylation tests.

Science.gov (United States)

Freire-Aradas, A; Phillips, C; Lareu, M V

2017-07-01

Individual age estimation is a key factor in forensic science analysis that can provide very useful information applicable to criminal, legal, and anthropological investigations. Forensic age inference was initially based on morphological inspection or radiography and only later began to adopt molecular approaches. However, a lack of accuracy or technical problems hampered the introduction of these DNA-based methodologies in casework analysis. A turning point occurred when the epigenetic signature of DNA methylation was observed to gradually change during an individual´s lifespan. In the last four years, the number of publications reporting DNA methylation age-correlated changes has gradually risen and the forensic community now has a range of age methylation tests applicable to forensic casework. Most forensic age predictor models have been developed based on blood DNA samples, but additional tissues are now also being explored. This review assesses the most widely adopted genes harboring methylation sites, detection technologies, statistical age-predictive analyses, and potential causes of variation in age estimates. Despite the need for further work to improve predictive accuracy and establishing a broader range of tissues for which tests can analyze the most appropriate methylation sites, several forensic age predictors have now been reported that provide consistency in their prediction accuracies (predictive error of ±4 years); this makes them compelling tools with the potential to contribute key information to help guide criminal investigations. Copyright © 2017 Central Police University.

Hope and Adaptation to Old Age: Their Relationship with Individual-Demographic Factors

Science.gov (United States)

Moraitou, Despina; Kolovou, Chrysa; Papasozomenou, Chrysa; Paschoula, Catherine

2006-01-01

This study examined the relationship between hope as disposition, adaptation to old age, and individual-demographic factors. One hundred and fifty older adults, aged 60-93 years old, completed the Adult Dispositional Hope Scale developed by Snyder et AL. [1991, Journal of Personality and Social Psychology, 60, pp. 570-585], and the Adaptation to…

Narayanaswamy's 1971 aging theory and material time

Science.gov (United States)

Dyre, Jeppe C.

2015-09-01

The Bochkov-Kuzovlev nonlinear fluctuation-dissipation theorem is used to derive Narayanaswamy's phenomenological theory of physical aging, in which this highly nonlinear phenomenon is described by a linear material-time convolution integral. A characteristic property of the Narayanaswamy aging description is material-time translational invariance, which is here taken as the basic assumption of the derivation. It is shown that only one possible definition of the material time obeys this invariance, namely, the square of the distance travelled from a configuration of the system far back in time. The paper concludes with suggestions for computer simulations that test for consequences of material-time translational invariance. One of these is the "unique-triangles property" according to which any three points on the system's path form a triangle such that two side lengths determine the third; this is equivalent to the well-known triangular relation for time-autocorrelation functions of aging spin glasses [L. F. Cugliandolo and J. Kurchan, J. Phys. A: Math. Gen. 27, 5749 (1994)]. The unique-triangles property implies a simple geometric interpretation of out-of-equilibrium time-autocorrelation functions, which extends to aging a previously proposed framework for such functions in equilibrium [J. C. Dyre, e-print arXiv:cond-mat/9712222 (1997)].

Effects of Individual Differences and Situational Features on Age Differences in Mindless Reading.

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Shake, Matthew C; Shulley, Leah J; Soto-Freita, Angelica M

2016-09-01

Mindless reading occurs when an individual shifts their attention away from the text and toward other off-task thoughts. This study examined whether previously reported age-related declines in mindless reading episodes are due primarily to (a) situational features related to the text itself (e.g., text genre or interest in the text) and/or (b) individual differences in cognitive ability. Participants read 2 texts written in different genres but about the same topic. During reading, they were randomly probed to indicate whether they were on-task or mind-wandering. They also indicated their perceptions regarding the interest and difficulty of the text, and completed a battery of cognitive ability measures. The results showed that (a) text genre may engender some age differences in mindless reading and (b) greater age and perceived interest in the text were each uniquely predictive of reduced mindless reading for both text genres. Individual differences in cognitive abilities (e.g., working memory, vocabulary) did not account for additional significant variance in mindless reading after interest and age were taken into account. Our findings are discussed in terms of implications for age differences in lapses of attention during reading and predictors of mind-wandering generally. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Regional Impact of Population Aging on Changes in Individual Self-perceptions of Aging: Findings From the German Ageing Survey.

Science.gov (United States)

Wolff, Julia K; Beyer, Ann-Kristin; Wurm, Susanne; Nowossadeck, Sonja; Wiest, Maja

2018-01-18

The importance of self-perceptions of aging (SPA) for health and longevity is well documented. Comparably little is known about factors that contribute to SPA. Besides individual factors, the context a person lives in may shape SPA. Research has so far focused on country-level differences in age stereotypes, indicating that rapid population aging accompanies more negative age stereotypes. The present study expands previous research by investigating the impact of district-specific population aging within one country on different facets of SPA. Based on a large representative survey in Germany, the study investigates changes in SPA as ongoing development as well as the SPA of physical loss over a 12-year period in adults aged 40+. The study uses several indicators of population aging (e.g., population development, average age, greying index), to identify four clusters differing in their pace of population aging. Based on three-level latent change models, these clusters were compared in their impact on changes in SPA. Compared to districts with an average rate of population aging, the study shows that persons living in regions with a fast population aging rate (C1) hold more negative SPA in both facets (ps = .01). Districts with slow population aging (C2) have significantly higher SPA ongoing development (p = .03). The study underlines the importance for regional differences in population aging on the development of SPA. In particular, societies should be aware that fast population aging may result in more negative SPA. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Longitudinal variability of time-location/activity patterns of population at different ages: a longitudinal study in California

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Cassady Diana L

2011-09-01

Full Text Available Abstract Background Longitudinal time-activity data are important for exposure modeling, since the extent to which short-term time-activity data represent long-term activity patterns is not well understood. This study was designed to evaluate longitudinal variations in human time-activity patterns. Method We report on 24-hour recall diaries and questionnaires collected via the internet from 151 parents of young children (mostly under age 55, and from 55 older adults of ages 55 and older, for both a weekday and a weekend day every three months over an 18-month period. Parents also provided data for their children. The self-administrated diary and questionnaire distinguished ~30 frequently visited microenvironments and ~20 activities which we selected to represent opportunities for exposure to toxic environmental compounds. Due to the non-normal distribution of time-location/activity data, we employed generalized linear mixed-distribution mixed-effect models to examine intra- and inter-individual variations. Here we describe variation in the likelihood of and time spent engaging in an activity or being in a microenvironment by age group, day-type (weekday/weekend, season (warm/cool, sex, employment status, and over the follow-up period. Results As expected, day-type and season influence time spent in many location and activity categories. Longitudinal changes were also observed, e.g., young children slept less with increasing follow-up, transit time increased, and time spent on working and shopping decreased during the study, possibly related to human physiological changes with age and changes in macro-economic factors such as gas prices and the economic recession. Conclusions This study provides valuable new information about time-activity assessed longitudinally in three major age groups and greatly expands our knowledge about intra- and inter-individual variations in time-location/activity patterns. Longitudinal variations beyond weekly and

Cognitive functions in middle aged individuals are related to metabolic disturbances and aerobic capacity

DEFF Research Database (Denmark)

Pedersen, Maria; Pedersen, Karin Kaereby; Bruunsgaard, Helle

2012-01-01

Metabolic disturbances may contribute to cognitive dysfunction in patients with type 2 diabetes. We investigated the relation between cognitive impairment and metabolic deteriorations, low physical fitness, low-grade inflammation and abdominal obesity in middle aged individuals.......Metabolic disturbances may contribute to cognitive dysfunction in patients with type 2 diabetes. We investigated the relation between cognitive impairment and metabolic deteriorations, low physical fitness, low-grade inflammation and abdominal obesity in middle aged individuals....

Association between age, distress, and orientations to happiness in individuals with disabilities.

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Terrill, Alexandra L; Müller, Rachel; Jensen, Mark P; Molton, Ivan R; Ipsen, Catherine; Ravesloot, Craig

2015-02-01

To determine how age and distress are associated in individuals with disabilities, and how happiness and its components (meaning, pleasure, and engagement) mediate or moderate this relationship. These were cross-sectional analyses of survey data from 508 community-dwelling adults with a variety of self-reported health conditions and functional disabilities. Measures included the Orientations to Happiness Questionnaire and items from the Behavior Risk Factor Surveillance System. Greater distress was associated with lower global happiness in both mediation and moderation models. The mediation model showed that middle-aged participants (age: 45-64) scored lowest in global happiness, and the effect of age on distress was partially mediated by happiness. None of the happiness components mediated the relationship of age on distress. The moderation model showed a significant interaction effect for age and global happiness on distress, where younger participants low on happiness were significantly more distressed. Of the three happiness components, only meaning was significantly associated with distress. There was a significant interaction between age and meaning, where participants who were younger and scored low on the meaning scale reported significantly higher distress. Findings from this study lay groundwork for the development of clinical interventions to address distress in individuals with functional disabilities. Middle-aged and younger people with disabilities may be particularly affected by lower levels of happiness and might benefit from psychological interventions that focus on increasing overall well-being and providing meaning and purpose in life. PsycINFO Database Record (c) 2015 APA, all rights reserved.

Age at the time of sulfonylurea initiation influences treatment outcomes in KCNJ11-related neonatal diabetes.

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Thurber, Brian W; Carmody, David; Tadie, Elizabeth C; Pastore, Ashley N; Dickens, Jazzmyne T; Wroblewski, Kristen E; Naylor, Rochelle N; Philipson, Louis H; Greeley, Siri Atma W

2015-07-01

Individuals with heterozygous activating mutations of the KCNJ11 gene encoding a subunit of the ATP-sensitive potassium channel (KATP) can usually be treated with oral sulfonylurea (SU) pills in lieu of insulin injections. The aim of this study was to test our hypothesis that younger age at the time of initiation of SU therapy is correlated with lower required doses of SU therapy, shorter transition time and decreased likelihood of requiring additional diabetes medications. We performed a retrospective cohort study using data on 58 individuals with neonatal diabetes due to KCNJ11 mutations identified through the University of Chicago Monogenic Diabetes Registry ( http://monogenicdiabetes.uchicago.edu/registry ). We assessed the influence of age at initiation of SU therapy on treatment outcomes. HbA1c fell from an average of 8.5% (69 mmol/mol) before transition to 6.2% (44 mmol/mol) after SU therapy (p < 0.001). Age of initiation of SU correlated with the dose (mg kg(-1) day(-1)) of SU required at follow-up (r = 0.80, p < 0.001). Similar associations were observed across mutation subtypes. Ten participants required additional glucose-lowering medications and all had initiated SU at age 13 years or older. No serious adverse events were reported. Earlier age at initiation of SU treatment is associated with improved response to SU therapy. Declining sensitivity to SU may be due to loss of beta cell mass over time in those treated with insulin. Our data support the need for early genetic diagnosis and appropriate personalised treatment in all cases of neonatal diabetes.

Sensitive plant (Mimosa pudica hiding time depends on individual and state

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Sarah Reed-Guy

2017-07-01

Full Text Available The decisions animals make to adjust their antipredator behavior to rapidly changing conditions have been well studied. Inducible defenses in plants are an antipredator behavior that acts on a longer time scale, but sensitive plants, Mimosa pudica, have a much more rapid antipredator response; they temporarily close their leaves when touched. The time they remain closed is defined as hiding time. We studied hiding time in sensitive plants and found that individual plants differed significantly in their hiding times. We then showed that the effect of individual explained substantial variation in hiding time on a short time scale. Finally, on a longer time scale, individuality persisted but the amount of variation attributed to individual decreased. We hypothesized that variation in plant condition might explain this change. We therefore manipulated sunlight availability and quantified hiding time. When deprived of light for 6 h, sensitive plants significantly shortened their hiding times. But when only half a plant was deprived of light, hiding times on the deprived half and light exposed half were not significantly different. This suggests that overall condition best explains variation in sensitive plant antipredator behavior. Just like in animals, sensitive plant antipredator behavior is condition dependent, and, just like in animals, a substantial amount of the remaining variation is explained by individual differences between plants. Thus, models designed to predict plasticity in animal behavior may be successfully applied to understand behavior in other organisms, including plants.

A marker of biological age explains individual variation in the strength of the adult stress response.

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Andrews, Clare; Nettle, Daniel; Larriva, Maria; Gillespie, Robert; Reichert, Sophie; Brilot, Ben O; Bedford, Thomas; Monaghan, Pat; Spencer, Karen A; Bateson, Melissa

2017-09-01

The acute stress response functions to prioritize behavioural and physiological processes that maximize survival in the face of immediate threat. There is variation between individuals in the strength of the adult stress response that is of interest in both evolutionary biology and medicine. Age is an established source of this variation-stress responsiveness diminishes with increasing age in a range of species-but unexplained variation remains. Since individuals of the same chronological age may differ markedly in their pace of biological ageing, we asked whether biological age-measured here via erythrocyte telomere length-predicts variation in stress responsiveness in adult animals of the same chronological age. We studied two cohorts of European starlings in which we had previously manipulated the rate of biological ageing by experimentally altering the competition experienced by chicks in the fortnight following hatching. We predicted that individuals with greater developmental telomere attrition, and hence greater biological age, would show an attenuated corticosterone (CORT) response to an acute stressor when tested as adults. In both cohorts, we found that birds with greater developmental telomere attrition had lower peak CORT levels and a more negative change in CORT levels between 15 and 30 min following stress exposure. Our results, therefore, provide strong evidence that a measure of biological age explains individual variation in stress responsiveness: birds that were biologically older were less stress responsive. Our results provide a novel explanation for the phenomenon of developmental programming of the stress response: observed changes in stress physiology as a result of exposure to early-life adversity may reflect changes in ageing.

Departure time choice: Modelling individual preferences, intention and constraints

DEFF Research Database (Denmark)

Thorhauge, Mikkel

by nearly all studies within departure time. More importantly it shows that the underlying psychological processes are more complex than simply accounting for attitudes and perceptions which are typically used in other areas. The work in this PhD thesis accounts for the full Theory of Planned Behaviour......, but can also be perceived by the individuals as barriers towards participating in activities. Perceived constraints affect the departure time choice through the individual intention of being on time. This PhD thesis also contributes to the departure time literature by discussing the problem of collecting...... whether they are constrained. The thesis also provides empirical evidences of the policy implication of not accounting for other activities and their constraints. Thirdly, the thesis shows that the departure time choice can be partly explained by psychological factors, which have previously been neglected...

[Towards a sheltered aging in individual and social responsibility].

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Birkenstock, E; Rentsch, T

2005-08-01

Aging is a slow process, the beginning of which as well as its progress are defined in quite different ways from the biomedical, psychological, or sociological point of view. Philosophy can perform a significant contribution to a sound and human approach to this phenomenon of life: first clarifying the present situation on the background of historic experiences; second improving a fundamental ascertainment of our ontological condition as human beings, characterized by finiteness and vulnerability, while recalling that humans possess the unique capability to reflect on this aspect of their existence; and, always moving from the results of that analysis, lastly suggesting some tentative solutions, conceived as ethical-practical guidelines and values pool, for an overcoming of the individual and social challenges posed by aging. The aim consists in a re-interpretation of aging as a "becoming oneself", without denying hereby the negativity embodied in the finiteness and fragility of our life. To this purpose it is necessary to distinguish the situations where aging, while maintaining full self-consciousness, can be shaped as an autonomous process, from those, mostly near to the edge of death, for which the goal of self-realization cannot be applied, making rather indispensable the resort to concepts of respect and empathy.

Influence of Age and Aerobic Fitness on the Multifractal Characteristics of Electrocardiographic RR Time-Series

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Michael James Lewis

2013-05-01

Full Text Available Multifractal properties of electrocardiographic inter-beat (RR time-series offer insight into its long-term correlation structure, independently of RR variability. Here we quantify multifractal characteristics of RR data during 24-hour diurnal-nocturnal activity in healthy participants. We tested the hypotheses that (1 age, gender and aerobic fitness influence RR multifractal properties, and that (2 these are influenced by circadian variation.Seventy adults (39 males aged 19-58 years and of various fitness levels were monitored using 24-hour ECG. Participants were dichotomised by median age and fitness for sub-group analysis. Gender and fitness were independent of age (p=0.1, p>0.5. Younger/older group ages were substantially different (p<0.0005 and were independent of gender and fitness. Multifractality was quantified using the probability spectrum of Hölder exponents (h, from which modal h (h* and the full-width and half-widths at half-maximum measures (FWHM, HWHM+ and HWHM- were derived. FWHM decreased (p=0.004 and h* increased (p=0.011 in older people, indicating diminished long-range RR correlations and weaker anti-persistent behavior. Anti-persistent correlation (h* was strongest in the youngest/fittest individuals and weakest in the oldest/least fit individuals (p=0.015. Long-range correlation (HWHM+/FWHM was strongest in the fittest males and weakest in the least fit females (p=0.007-0.033.Multifractal RR characteristics in our healthy participants showed strong age-dependence with diminished long-range anti-persistent correlation in older people. Circadian variation of these characteristics was influenced by fitness and gender: fitter males and females of all ages had the greatest degree of multifractality or long-range order. Multifractal characterisation appears to be a useful method for exploring the physiological basis of long-term correlation structure in RR time-series as well as the benefits thereon of physical fitness training.

Individual, contextual, and age-related acoustic variation in Simakobu (Simias concolor loud calls.

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Wendy M Erb

Full Text Available Primate loud calls have the potential to encode information about the identity, arousal, age, or physical condition of the caller, even at long distances. In this study, we conducted an analysis of the acoustic features of the loud calls produced by a species of Asian colobine monkey (simakobu, Simias concolor. Adult male simakobu produce loud calls spontaneously and in response to loud sounds and other loud calls, which are audible more than 500 m. Individual differences in calling rates and durations exist, but it is unknown what these differences signal and which other acoustic features vary among individuals. We aimed to describe the structure and usage of calls and to examine acoustic features that vary within and among individuals. We determined the context of 318 loud calls and analyzed 170 loud calls recorded from 10 adult males at an undisturbed site, Pungut, Siberut Island, Indonesia. Most calls (53% followed the loud call of another male, 31% were spontaneous, and the remaining 16% followed a loud environmental disturbance. The fundamental frequency (F0 decreased while inter-unit intervals (IUI increased over the course of loud call bouts, possibly indicating caller fatigue. Discriminant function analysis indicated that calls were not well discriminated by context, but spontaneous calls had higher peak frequencies, suggesting a higher level of arousal. Individual calls were distinct and individuals were mainly discriminated by IUI, call duration, and F0. Loud calls of older males had shorter IUI and lower F0, while middle-aged males had the highest peak frequencies. Overall, we found that calls were individually distinct and may provide information about the age, stamina, and arousal of the calling male, and could thus be a way for males and females to assess competitors and mates from long distances.

Digital information culture the individual and society in the digital age

CERN Document Server

Tredinnick, Luke

2008-01-01

Digital Information Culture is an introduction to the cultural, social and political impact of digital information and digital resources. The book is organised around themes, rather than theories and is arranged into three sections: culture, society and the individual. Each explores key elements of the social, cultural and political impact of digital information. The culture section outlines the origins of cyber culture in fifties pulp-fiction through to the modern day. It explores the issues of information overload, the threat of a digital dark age, and the criminal underbelly of digital culture. Section two, society, explores the economic and social impact of digital information, outlining key theories of the Information Age. Section three explores the impact of digital information and digital resources on the individual, exploring the changing nature of identity in a digital world. Written by a leading author in the field Focuses on digital information and its social, cultural and political impact is uniqu...

Physiological frailty index (PFI): quantitative in-life estimate of individual biological age in mice.

Science.gov (United States)

Antoch, Marina P; Wrobel, Michelle; Kuropatwinski, Karen K; Gitlin, Ilya; Leonova, Katerina I; Toshkov, Ilia; Gleiberman, Anatoli S; Hutson, Alan D; Chernova, Olga B; Gudkov, Andrei V

2017-03-19

The development of healthspan-extending pharmaceuticals requires quantitative estimation of age-related progressive physiological decline. In humans, individual health status can be quantitatively assessed by means of a frailty index (FI), a parameter which reflects the scale of accumulation of age-related deficits. However, adaptation of this methodology to animal models is a challenging task since it includes multiple subjective parameters. Here we report a development of a quantitative non-invasive procedure to estimate biological age of an individual animal by creating physiological frailty index (PFI). We demonstrated the dynamics of PFI increase during chronological aging of male and female NIH Swiss mice. We also demonstrated acceleration of growth of PFI in animals placed on a high fat diet, reflecting aging acceleration by obesity and provide a tool for its quantitative assessment. Additionally, we showed that PFI could reveal anti-aging effect of mTOR inhibitor rapatar (bioavailable formulation of rapamycin) prior to registration of its effects on longevity. PFI revealed substantial sex-related differences in normal chronological aging and in the efficacy of detrimental (high fat diet) or beneficial (rapatar) aging modulatory factors. Together, these data introduce PFI as a reliable, non-invasive, quantitative tool suitable for testing potential anti-aging pharmaceuticals in pre-clinical studies.

Future time perspective and awareness of age-related change: Examining their role in predicting psychological well-being.

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Brothers, Allyson; Gabrian, Martina; Wahl, Hans-Werner; Diehl, Manfred

2016-09-01

This study examined how 2 distinct facets of perceived personal lifetime-future time perspective (FTP) and awareness of age-related change (AARC)-are associated with another, and how they may interact to predict psychological well-being. To better understand associations among subjective perceptions of lifetime, aging, and well-being, we tested a series of models to investigate questions of directionality, indirect effects, and conditional processes among FTP, AARC-Gains, AARC-Losses, and psychological well-being. In all models, we tested for differences between middle-aged and older adults, and between adults from the United States and Germany. Analyses were conducted within a structural equation modeling framework on a cross-national, 2.5-year longitudinal sample of 537 community-residing adults (age 40-98 years). Awareness of age-related losses (AARC-Losses) at Time 1 predicted FTP at Time 2, but FTP did not predict AARC-Gains or AARC-Losses. Furthermore, future time perspective mediated the association between AARC-Losses and well-being. Moderation analyses revealed a buffering effect of awareness of age-related gains (AARC-Gains) in which perceptions of more age-related gains diminished the negative effect of a limited future time perspective on well-being. Effects were robust across age groups and countries. Taken together, these findings suggest that perceived age-related loss experiences may sensitize individuals to perceive a more limited future lifetime which may then lead to lower psychological well-being. In contrast, perceived age-related gains may function as a resource to preserve psychological well-being, in particular when time is perceived as running out. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Retail yields and palatability evaluations of individual muscles from wet-aged and dry-aged beef ribeyes and top sirloin butts that were merchandised innovatively.

Science.gov (United States)

Smith, A M; Harris, K B; Griffin, D B; Miller, R K; Kerth, C R; Savell, J W

2014-05-01

Paired ribeyes (n=24) and top sirloin butts (n=24) were dry-aged or wet-aged for 35 days before being merchandised as individual muscles: M. spinalis thoracis, M. longissimus thoracis, M. gluteobiceps, and M. gluteus medius. Wet-aged subprimals had greater saleable yields than dry-aged. Dry-aged M. spinalis thoracis and M. gluteobiceps received lower consumer overall like and flavor ratings than did wet-aged; interior muscles - M. longissimus thoracis and M. gluteus medius - did not differ. Trained panelists found higher musty and putrid flavors for dry-aged muscles closer to exterior surface. These flavors may have contributed to lower consumer overall like and flavor ratings for dry-aged M. spinalis thoracis and M. gluteobiceps. Using innovative styles to cut beef allows for greater merchandising options. However, development of undesirable flavor characteristics may be more pronounced when exterior muscles - M. spinalis thoracis and M. gluteobiceps - are exposed during dry-aging to extreme conditions and are consumed individually. Copyright © 2013 Elsevier Ltd. All rights reserved.

Narayanaswamy’s 1971 aging theory and material time

International Nuclear Information System (INIS)

Dyre, Jeppe C.

2015-01-01

The Bochkov-Kuzovlev nonlinear fluctuation-dissipation theorem is used to derive Narayanaswamy’s phenomenological theory of physical aging, in which this highly nonlinear phenomenon is described by a linear material-time convolution integral. A characteristic property of the Narayanaswamy aging description is material-time translational invariance, which is here taken as the basic assumption of the derivation. It is shown that only one possible definition of the material time obeys this invariance, namely, the square of the distance travelled from a configuration of the system far back in time. The paper concludes with suggestions for computer simulations that test for consequences of material-time translational invariance. One of these is the “unique-triangles property” according to which any three points on the system’s path form a triangle such that two side lengths determine the third; this is equivalent to the well-known triangular relation for time-autocorrelation functions of aging spin glasses [L. F. Cugliandolo and J. Kurchan, J. Phys. A: Math. Gen. 27, 5749 (1994)]. The unique-triangles property implies a simple geometric interpretation of out-of-equilibrium time-autocorrelation functions, which extends to aging a previously proposed framework for such functions in equilibrium [J. C. Dyre, e-print arXiv:cond-mat/9712222 (1997)

Population biology of intestinal Enterococcus Isolates from hospitalized and nonhospitalized individuals in different age groups

NARCIS (Netherlands)

Tedim, Ana P.; Ruiz-Garbajosa, Patricia; Corander, Jukka; Rodríguez, Concepción M.; Cantón, Rafael; Willems, Rob J.; Baquero, Fernando; Coque, Teresa M.

2015-01-01

The diversity of enterococcal populations from fecal samples from hospitalized (n=133) and nonhospitalized individuals (n= 173) of different age groups (group I, ages 0 to 19 years; group II, ages 20 to 59 years; group III, ages≥60 years) was analyzed. Enterococci were recovered at similar rates

Age of majority assessment in Dutch individuals based on Cameriere's third molar maturity index

NARCIS (Netherlands)

Boyacıoğlu Doğru, H.; Gulsahi, A.; Burçak Çehreli, S.; Galić, I.; van der Stelt, P.; Cameriere, R.

2018-01-01

Radiological examination of the third molar is done in living individuals for estimation of chronological age, especially in the late adolescence. The aim of this study was to assess the application of Cameriere's third molar maturity index (I3M) to determine whether an individual is 18 years or

Investigation of individuals going to coffeehouse with the aim of leisure time activities

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Hüseyin ÖZTÜRK

2015-08-01

Full Text Available The main basis of this research is to investigate pe ople going to coffeehouse with the aim of leisure time activities. The research group of this study consist of individuals going to the coffeehouses with the aim of leisure time activities in the city of Gaz iantep, Turkey. A total of 421 individuals joined to the research voluntarily. The Research consists of two parts. In the first part, personal information was used. In the second part, the leisure questionnaire form developed by Binarbaşı (2006 was u sed in order to determine individuals’ leisure time habits. The statistical programme SPSS 16.0 software packed programme was used to analyze the data. While analyzing the data, descriptive statistics methods were used as frequency percentage so P <0.05 was considered statistically significant. As the result of research; it is seen that 41 years of age and older people prefer going to coffehouses more than the others, the big majority of them are elementary and junior high school graduates and mostly they are married people, mostly they have 1 - 2 children, as a profession they are mostly workers who take minimum wage and they work very little over salary as monthly income. People going to the coffeehouses in their free time preffered at a high rate that they mostly go to the coffeehouses to spend time with their friends, they are happy with this activity, in the same time they find it very relaxing and they mostly watch TV when they don’t go to coffeehouses in their spare time and they in dicated the reason for failure to participate in other activities except coffeehouses as the absence of relevant activities and programmes appealing to them and economic handicap.

DNA methylation-based measures of biological age: meta-analysis predicting time to death

Science.gov (United States)

Chen, Brian H.; Marioni, Riccardo E.; Colicino, Elena; Peters, Marjolein J.; Ward-Caviness, Cavin K.; Tsai, Pei-Chien; Roetker, Nicholas S.; Just, Allan C.; Demerath, Ellen W.; Guan, Weihua; Bressler, Jan; Fornage, Myriam; Studenski, Stephanie; Vandiver, Amy R.; Moore, Ann Zenobia; Tanaka, Toshiko; Kiel, Douglas P.; Liang, Liming; Vokonas, Pantel; Schwartz, Joel; Lunetta, Kathryn L.; Murabito, Joanne M.; Bandinelli, Stefania; Hernandez, Dena G.; Melzer, David; Nalls, Michael; Pilling, Luke C.; Price, Timothy R.; Singleton, Andrew B.; Gieger, Christian; Holle, Rolf; Kretschmer, Anja; Kronenberg, Florian; Kunze, Sonja; Linseisen, Jakob; Meisinger, Christine; Rathmann, Wolfgang; Waldenberger, Melanie; Visscher, Peter M.; Shah, Sonia; Wray, Naomi R.; McRae, Allan F.; Franco, Oscar H.; Hofman, Albert; Uitterlinden, André G.; Absher, Devin; Assimes, Themistocles; Levine, Morgan E.; Lu, Ake T.; Tsao, Philip S.; Hou, Lifang; Manson, JoAnn E.; Carty, Cara L.; LaCroix, Andrea Z.; Reiner, Alexander P.; Spector, Tim D.; Feinberg, Andrew P.; Levy, Daniel; Baccarelli, Andrea; van Meurs, Joyce; Bell, Jordana T.; Peters, Annette; Deary, Ian J.; Pankow, James S.; Ferrucci, Luigi; Horvath, Steve

2016-01-01

Estimates of biological age based on DNA methylation patterns, often referred to as “epigenetic age”, “DNAm age”, have been shown to be robust biomarkers of age in humans. We previously demonstrated that independent of chronological age, epigenetic age assessed in blood predicted all-cause mortality in four human cohorts. Here, we expanded our original observation to 13 different cohorts for a total sample size of 13,089 individuals, including three racial/ethnic groups. In addition, we examined whether incorporating information on blood cell composition into the epigenetic age metrics improves their predictive power for mortality. All considered measures of epigenetic age acceleration were predictive of mortality (p≤8.2×10−9), independent of chronological age, even after adjusting for additional risk factors (p<5.4×10−4), and within the racial/ethnic groups that we examined (non-Hispanic whites, Hispanics, African Americans). Epigenetic age estimates that incorporated information on blood cell composition led to the smallest p-values for time to death (p=7.5×10−43). Overall, this study a) strengthens the evidence that epigenetic age predicts all-cause mortality above and beyond chronological age and traditional risk factors, and b) demonstrates that epigenetic age estimates that incorporate information on blood cell counts lead to highly significant associations with all-cause mortality. PMID:27690265

Analyzing Developmental Processes on an Individual Level Using Nonstationary Time Series Modeling

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Molenaar, Peter C. M.; Sinclair, Katerina O.; Rovine, Michael J.; Ram, Nilam; Corneal, Sherry E.

2009-01-01

Individuals change over time, often in complex ways. Generally, studies of change over time have combined individuals into groups for analysis, which is inappropriate in most, if not all, studies of development. The authors explain how to identify appropriate levels of analysis (individual vs. group) and demonstrate how to estimate changes in…

Cognitive reserve and emotional stimuli in older individuals: level of education moderates the age-related positivity effect.

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Bruno, Davide; Brown, Adam D; Kapucu, Aycan; Marmar, Charles R; Pomara, Nunzio

2014-01-01

BACKGROUND/STUDY CONTEXT: A frequently observed age-related effect is a preference in older individuals for positive stimuli. The cognitive control model proposes that this positivity effect may be mediated by executive functions. We propose that cognitive reserve, operationally defined as years of education, which tempers cognitive decline and has been linked to executive functions, should also influence the age-related positivity effect, especially as age advances. An emotional free recall test was administered to a group of 84 cognitively intact individuals aged 60 to 88, who varied in years of education. As part of a larger test battery, data were obtained on measures of executive functioning and depression. Multiple regression and moderation analyses were performed, controlling for general cognitive function, severity of depressive symptoms, and executive function. In our data, years of education appeared to moderate the effect of age on the positivity effect; age was negatively associated with recall of positive words in participants with fewer years of education, whereas a nonsignificant positive correlation was observed between age and positivity in participants with more education. Cognitive reserve appears to play a role in explaining individual differences in the positivity effect in healthy older individuals. Future studies should investigate whether cognitive reserve is also implicated in the ability to process a wide range of emotional stimuli and whether greater reserve is reflected in improved emotional regulation.

Age-related and Individual Variation in Male Piezodorus hybneri (Heteroptera: Pentatomidae Pheromones

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Nobuyuki Endo

2012-01-01

Full Text Available Males of the Piezodorus hybneri stink bug produce a pheromone comprising β-sesquiphellandrene (Sesq, (R-15-hexadecanolide (R15, and methyl (Z-8-hexadecenoate (Z8. We collected airborne volatiles from individual P. hybneri males and analyzed them by GC-MS. Daily analysis from 1 to 16 days after adult emergence showed that pheromone emission started around 3 to 6 days after adult emergence and peaked (~1 μg/male/day on day 11. The proportion of Sesq tended to increase with age to about 80% on days 12 to 16. On the other hand, the proportion of R15 tended to decrease with age. The proportion of Z8 reached a maximum of about 34% on day 9 but otherwise remained below 20%. The total amount of pheromone emitted by individual males varied considerably: three males emitted more than 10 μg, whereas another three males emitted little or no pheromone and failed to survive by the end of the experiment. These results suggest that the amount of P. hybneri pheromone and its blend ratio could be affected by the male’s physical conditions, such as vitality and age.

Time variable cosmological constants from the age of universe

International Nuclear Information System (INIS)

Xu Lixin; Lu Jianbo; Li Wenbo

2010-01-01

In this Letter, time variable cosmological constant, dubbed age cosmological constant, is investigated motivated by the fact: any cosmological length scale and time scale can introduce a cosmological constant or vacuum energy density into Einstein's theory. The age cosmological constant takes the form ρ Λ =3c 2 M P 2 /t Λ 2 , where t Λ is the age or conformal age of our universe. The effective equation of state (EoS) of age cosmological constant are w Λ eff =-1+2/3 (√(Ω Λ ))/c and w Λ eff =-1+2/3 (√(Ω Λ ))/c (1+z) when the age and conformal age of universe are taken as the role of cosmological time scales respectively. The EoS are the same as the so-called agegraphic dark energy models. However, the evolution histories are different from the agegraphic ones for their different evolution equations.

Effect of ageing time and temperature on the strain ageing behaviour of quenched zircaloy-4

International Nuclear Information System (INIS)

Rheem, K.S.; Park, W.K.; Yook, C.C.

1977-01-01

The strain ageing behaviour of quenched Zircaloy-4 has been studied as a function of ageing time and temperature in the temperature range 523-588 K for a short-ageing time of 1 to 52 seconds. A the test conditions, the strain ageing stress increased with ageing time and temperature at a strain rate of 5.55x10 -4 sec -1 . Applying stress on the quenched Zircaloy-4, the strain ageing effect indicated following two states: an initial stage having an activation energy of 0.39ev considered to be due to Snoek type ordering of interstitial oxygen atoms in the stress field of a dislocaiton and a second stage havingan activation energy of 0.60 ev, due to mainly long range diffusion of oxygen atoms. (author)

Financial times: Competing temporalities in the age of finance capitalism

Directory of Open Access Journals (Sweden)

Christian Kloeckner

2018-05-01

Full Text Available This special issue explores how finance deploys time, structures the future, and interacts with actors and institutions that sometimes function according to very different temporal regimes. Finance capitalism’s logic of recurrence, repetitive cycles, and successive ruptures has long been with us, but the essays in this special issue are particularly interested in how recent decades of intensified financialization have restructured temporal experience. They interrogate the production and dissemination of agency in an age of acceleration, risk, and uncertainty, asking how the temporality inscribed in financial transactions emerges from and simultaneously shapes individual and social practice. Topics covered range from the logic of finance and foundational concepts of financial theory to the intersection between objective structures and social practice, the role of literature, and finally questions of social insecurity, political action, and the possibility of resistance within a context of competing temporalities. In this introduction, the editors delineate some fundamental concepts and questions for our financial times.

Narayanaswamy’s 1971 aging theory and material time

DEFF Research Database (Denmark)

Dyre, Jeppe C.

2015-01-01

The Bochkov-Kuzovlev nonlinear fluctuation-dissipation theorem is used to derive Narayanaswamy’s phenomenological theory of physical aging, in which this highly nonlinear phenomenon is described by a linear material-time convolution integral. A characteristic property of the Narayanaswamy aging...... description is material-time translational invariance, which is here taken as the basic assumption of the derivation. It is shown that only one possible definition of the material time obeys this invariance, namely, the square of the distance travelled from a configuration of the system far back in time...

C Reactive protein levels as a marker of coronary heart disease in middle aged individuals

International Nuclear Information System (INIS)

Haleem, N.; Marwat, Z.I.; Abbasi, S.; Tauqeer, S.

2016-01-01

Background: coronary heart disease is multifactorial inflammatory process which involves the accumulation of lipid macrophages and intimal plaques in smooth muscle cell in large and medium sized arteries. C reactive protein (CRP) which is an inflammatory marker is considered as global risk assessment for coronary heart disease. The objective of study is to determine the CRP level as risk marker in coronary heart disease in middle aged individuals. Methods: This cross sectional study was conducted in Hayatabad medical complex Peshawar and Rehman Medical Institute Peshawar. On the basis of predesigned questionnaire, 100 middle aged individuals of age 40-60 years and 50 normal subjects of same age were questioned by taking consent. Data was collected and analysed by SPSS-15. Results: It was founded that 74 percentage of patients have higher values of CRP and 4 percentage have high values of CRP in controls. The t-test applied at 95 percentage confidence interval with mean difference of 22.096+2.36 of CHD individuals and 1.288±1.70 of control group. P-value was 0.001 which is found to be significant. Conclusion: It was observed that CRP has higher association with CHD. (author)

With age a lower individual breathing reserve is associated with a higher maximal heart rate.

Science.gov (United States)

Burtscher, Martin; Gatterer, Hannes; Faulhaber, Martin; Burtscher, Johannes

2018-01-01

Maximal heart rate (HRmax) is linearly declining with increasing age. Regular exercise training is supposed to partly prevent this decline, whereas sex and habitual physical activity do not. High exercise capacity is associated with a high cardiac output (HR x stroke volume) and high ventilatory requirements. Due to the close cardiorespiratory coupling, we hypothesized that the individual ventilatory response to maximal exercise might be associated with the age-related HRmax. Retrospective analyses have been conducted on the results of 129 consecutively performed routine cardiopulmonary exercise tests. The study sample comprised healthy subjects of both sexes of a broad range of age (20-86 years). Maximal values of power output, minute ventilation, oxygen uptake and heart rate were assessed by the use of incremental cycle spiroergometry. Linear multivariate regression analysis revealed that in addition to age the individual breathing reserve at maximal exercise was independently predictive for HRmax. A lower breathing reserve due to a high ventilatory demand and/or a low ventilatory capacity, which is more pronounced at a higher age, was associated with higher HRmax. Age explained the observed variance in HRmax by 72% and was improved to 83% when the variable "breathing reserve" was entered. The presented findings indicate an independent association between the breathing reserve at maximal exercise and maximal heart rate, i.e. a low individual breathing reserve is associated with a higher age-related HRmax. A deeper understanding of this association has to be investigated in a more physiological scenario. Copyright © 2017 Elsevier B.V. All rights reserved.

Age-specific and sex-specific prevalence of cerebral β-amyloidosis, tauopathy, and neurodegeneration in cognitively unimpaired individuals aged 50-95 years: a cross-sectional study.

Science.gov (United States)

Jack, Clifford R; Wiste, Heather J; Weigand, Stephen D; Therneau, Terry M; Knopman, David S; Lowe, Val; Vemuri, Prashanthi; Mielke, Michelle M; Roberts, Rosebud O; Machulda, Mary M; Senjem, Matthew L; Gunter, Jeffrey L; Rocca, Walter A; Petersen, Ronald C

2017-06-01

A new classification for biomarkers in Alzheimer's disease and cognitive ageing research is based on grouping the markers into three categories: amyloid deposition (A), tauopathy (T), and neurodegeneration or neuronal injury (N). Dichotomising these biomarkers as normal or abnormal results in eight possible profiles. We determined the clinical characteristics and prevalence of each ATN profile in cognitively unimpaired individuals aged 50 years and older. All participants were in the Mayo Clinic Study of Aging, a population-based study that uses a medical records linkage system to enumerate all individuals aged 50-89 years in Olmsted County, MN, USA. Potential participants are randomly selected, stratified by age and sex, and invited to participate in cognitive assessments; individuals without medical contraindications are invited to participate in brain imaging studies. Participants who were judged clinically as having no cognitive impairment and underwent multimodality imaging between Oct 11, 2006, and Oct 5, 2016, were included in the current study. Participants were classified as having normal (A-) or abnormal (A+) amyloid using amyloid PET, normal (T-) or abnormal (T+) tau using tau PET, and normal (N-) or abnormal (N+) neurodegeneration or neuronal injury using cortical thickness assessed by MRI. We used the cutoff points of standard uptake value ratio (SUVR) 1·42 (centiloid 19) for amyloid PET, 1·23 SUVR for tau PET, and 2·67 mm for MRI cortical thickness. Age-specific and sex-specific prevalences of the eight groups were determined using multinomial models combining data from 435 individuals with amyloid PET, tau PET, and MRI assessments, and 1113 individuals who underwent amyloid PET and MRI, but not tau PET imaging. The numbers of participants in each profile group were 165 A-T-N-, 35 A-T+N-, 63 A-T-N+, 19 A-T+N+, 44 A+T-N-, 25 A+T+N-, 35 A+T-N+, and 49 A+T+N+. Age differed by ATN group (pgroup (p=0·04), with carriers roughly twice as frequent in each

Individual and contextual antecedents of workplace aggression in aged care nurses and certified nursing assistants.

Science.gov (United States)

Rodwell, John; Demir, Defne; Gulyas, Andre

2015-08-01

Employees in aged care are at high risk of workplace aggression. Research rarely examines the individual and contextual antecedents of aggression for specific types of workers within these settings, such as nurses and certified nursing assistants (CNAs). The study aimed to explore characteristics of the job demands-resources model (JD-R), negative affectivity (NA) and demographics related to workplace aggression for aged care workers. The survey study was based on 208 nurses and 83 CNAs working within aged care. Data from each group were analysed separately using ordinal regressions. Both aged care nurses and CNAs reported high rates of bullying, external emotional abuse, threat of assault and physical assault. Elements of the JD-R model and individual characteristics were related to aggression types for both groups. Characteristics of the JD-R model, NA and demographics are important in understanding the antecedents of aggression observed among aged care workers. © 2015 Wiley Publishing Asia Pty Ltd.

Age-Related Change in Vestibular Ganglion Cell Populations in Individuals With Presbycusis and Normal Hearing.

Science.gov (United States)

Gluth, Michael B; Nelson, Erik G

2017-04-01

We sought to establish that the decline of vestibular ganglion cell counts uniquely correlates with spiral ganglion cell counts, cochlear hair cell counts, and hearing phenotype in individuals with presbycusis. The relationship between aging in the vestibular system and aging in the cochlea is a topic of ongoing investigation. Histopathologic age-related changes the vestibular system may mirror what is seen in the cochlea, but correlations with hearing phenotype and the impact of presbycusis are not well understood. Vestibular ganglion cells, spiral ganglion cells, and cochlear hair cells were counted in specimens from individuals with presbycusis and normal hearing. These were taken from within a large collection of processed human temporal bones. Correlations between histopathology and hearing phenotype were investigated. Vestibular ganglion cell counts were positively correlated with spiral ganglion cell counts and cochlear hair cell counts and were negatively correlated with hearing phenotype. There was no statistical evidence on linear regression to suggest that the relationship between age and cell populations differed significantly according to whether presbycusis was present or not. Superior vestibular ganglion cells were more negatively correlated with age than inferior ganglion cells. No difference in vestibular ganglion cells was noted based on sex. Vestibular ganglion cell counts progressively deteriorate with age, and this loss correlates closely with changes in the cochlea, as well as hearing phenotype. However, these correlations do not appear to be unique in individuals with presbycusis as compared with those with normal hearing.

Effect of individual thinking styles on item selection during study time allocation.

Science.gov (United States)

Jia, Xiaoyu; Li, Weijian; Cao, Liren; Li, Ping; Shi, Meiling; Wang, Jingjing; Cao, Wei; Li, Xinyu

2018-04-01

The influence of individual differences on learners' study time allocation has been emphasised in recent studies; however, little is known about the role of individual thinking styles (analytical versus intuitive). In the present study, we explored the influence of individual thinking styles on learners' application of agenda-based and habitual processes when selecting the first item during a study-time allocation task. A 3-item cognitive reflection test (CRT) was used to determine individuals' degree of cognitive reliance on intuitive versus analytical cognitive processing. Significant correlations between CRT scores and the choices of first item selection were observed in both Experiment 1a (study time was 5 seconds per triplet) and Experiment 1b (study time was 20 seconds per triplet). Furthermore, analytical decision makers constructed a value-based agenda (prioritised high-reward items), whereas intuitive decision makers relied more upon habitual responding (selected items from the leftmost of the array). The findings of Experiment 1a were replicated in Experiment 2 notwithstanding ruling out the possible effects from individual intelligence and working memory capacity. Overall, the individual thinking style plays an important role on learners' study time allocation and the predictive ability of CRT is reliable in learners' item selection strategy. © 2016 International Union of Psychological Science.

Who should take care of me? Preferences of old age individuals for characteristics of professional long-term caregivers: an observational cross-sectional study.

Science.gov (United States)

Hajek, André; Lehnert, Thomas; Wegener, Annemarie; Riedel-Heller, Steffi G; König, Hans-Helmut

2017-08-10

It is most likely that the need for long-term care increases considerably in the next decades due to demographic shifts. Thus, we aimed at identifying the preferences for characteristics of professional long-term caregivers among old age individuals in Germany. Data were gathered from a population-based survey of the German population aged 65 and above in 2015 (n = 1006). It was important for individuals in old age that long-term caregivers were 'empathetic, kind' (99.3%), 'punctual, reliable' (98.2%), have an 'orderly appearance' (96.4%), work in a 'small team' (92.5%) and have 'enough time' (91.5%). Moreover, while most of the individuals (76.5%) reported high preferences for 'German language', the preferences were lower for 'same cultural background' (54.2%) and 'same gender' (35.7%). In multiple logistic regressions, preferences for 'same gender' were positively associated with being female [OR 8.3 (5.6-12.1)], living with partner or spouse [OR 1.4 (1.0-1.9)], and being born abroad [OR 1.8 (1.1-3.1)]. Preferences for 'German language' were positively associated with being female [OR: 1.5 (1.1-2.1)]. Preferences for 'same cultural background' were positively associated with age [OR 1.0 (1.0-1.1)], living with partner or spouse [OR 1.4 (1.0-1.9)], and East Germany [OR 1.9 (1.3-2.7)]. Preferences for 'orderly appearance', 'empathetic, kind', 'punctual, reliable' and 'small nursing team' were all not significantly associated with included independent variables, whereas preferences for 'enough time' were positively associated with being female [OR 1.9 (1.1-3.5)], living with partner or spouse [OR 1.9 (1.1-3.4)], education [Apprenticeship, full-time vocational school, OR 3.1 (1.3-7.6)], not providing care for family/friends [OR 1.9 (1.1-3.3)], and involvement in the issue of need for care [OR 1.3 (1.1-1.6)]. Our data suggest that it is important to almost every individual aged 65 and above in Germany that professional long-term caregivers are (i) empathetic, kind

Aging in Context: Individual and Environmental Pathways to Aging-Friendly Communities-The 2015 Matthew A. Pollack Award Lecture.

Science.gov (United States)

Scharlach, Andrew E

2017-08-01

Reflecting the theme of the 2015 Gerontological Society of America (GSA) Annual Scientific Meeting, "Aging as a Lifelong Process," this paper examines intersections between aging processes and their environmental context, develops theory regarding constructive developmental processes and their environmental context, and considers potential implications for conceptualizing and creating aging-friendly communities. The first section examines the primary goals of aging-friendly communities, that is, promoting elder well-being. The second section explores the role of environmental pathways in fostering well-being throughout the lifecourse. The third section presents a new Process Model of Constructive Aging that identifies key developmental processes at the intersection of individual and environmental pathways. The final section considers potential implications for creating aging-friendly communities, including ways in which cities and towns can promote the ability of community members to live fully throughout their lives, and identifies some key conceptual and empirical challenges affecting the future of the field. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Individual and maternal determinants of self-reported dental health among Turkish school children aged 10-12 years

DEFF Research Database (Denmark)

Cinar, A B; Kosku, N; Sandalli, N

2008-01-01

To assess the influence of maternal and individual characteristics on self-reported dental health of Turkish school children aged 10-12 years with different socio-economic backgrounds.......To assess the influence of maternal and individual characteristics on self-reported dental health of Turkish school children aged 10-12 years with different socio-economic backgrounds....

Do Individual Differences and Aging Effects in the Estimation of Geographical Slant Reflect Cognitive or Perceptual Effects?

Directory of Open Access Journals (Sweden)

Abigail M. Dean

2016-07-01

Full Text Available Several individual differences including age have been suggested to affect the perception of slant. A cross-sectional study of outdoor hill estimation (N = 106 was analyzed using individual difference measures of age, experiential knowledge, fitness, personality traits, and sex. Of particular note, it was found that for participants who reported any experiential knowledge about slant, estimates decreased (i.e., became more accurate as conscientiousness increased, suggesting that more conscientious individuals were more deliberate about taking their experiential knowledge (rather than perception into account. Effects of fitness were limited to those without experiential knowledge, suggesting that they, too, may be cognitive rather than perceptual. The observed effects of age, which tended to produce lower, more accurate estimates of hill slant, provide more evidence that older adults do not see hills as steeper. The main effect of age was to lower slant estimates; such effects may be due to implicit experiential knowledge acquired over a lifetime. The results indicate the impact of cognitive, rather than perceptual factors on individual differences in slant estimation.

Individual differences and predictors of forgetting in old age: the role of processing speed and working memory.

Science.gov (United States)

Zimprich, Daniel; Kurtz, Tanja

2013-01-01

The goal of the present study was to examine whether individual differences in basic cognitive abilities, processing speed, and working memory, are reliable predictors of individual differences in forgetting rates in old age. The sample for the present study comprised 364 participants aged between 65 and 80 years from the Zurich Longitudinal Study on Cognitive Aging. The impact of basic cognitive abilities on forgetting was analyzed by modeling working memory and processing speed as predictors of the amount of forgetting of 27 words, which had been learned across five trials. Forgetting was measured over a 30-minute interval by using parceling and a latent change model, in which the latent difference between recall performance after five learning trials and a delayed recall was modeled. Results implied reliable individual differences in forgetting. These individual differences in forgetting were strongly related to processing speed and working memory. Moreover, an age-related effect, which was significantly stronger for forgetting than for learning, emerged even after controlling effects of processing speed and working memory.

Age-Related Differences of Individuals' Arithmetic Strategy Utilization with Different Level of Math Anxiety.

Science.gov (United States)

Si, Jiwei; Li, Hongxia; Sun, Yan; Xu, Yanli; Sun, Yu

2016-01-01

The present study used the choice/no-choice method to investigate the effect of math anxiety on the strategy used in computational estimation and mental arithmetic tasks and to examine age-related differences in this regard. Fifty-seven fourth graders, 56 sixth graders, and 60 adults were randomly selected to participate in the experiment. Results showed the following: (1) High-anxious individuals were more likely to use a rounding-down strategy in the computational estimation task under the best-choice condition. Additionally, sixth-grade students and adults performed faster than fourth-grade students on the strategy execution parameter. Math anxiety affected response times (RTs) and the accuracy with which strategies were executed. (2) The execution of the partial-decomposition strategy was superior to that of the full-decomposition strategy on the mental arithmetic task. Low-math-anxious persons provided more accurate answers than did high-math-anxious participants under the no-choice condition. This difference was significant for sixth graders. With regard to the strategy selection parameter, the RTs for strategy selection varied with age.

Developing pongid dentition and its use for ageing individual crania in comparative cross-sectional growth studies.

Science.gov (United States)

Dean, M C; Wood, B A

1981-01-01

This study of the developing pongid dentition is based on cross-sectional radiographic data of juvenile Pan troglodytes, Gorilla gorilla, and Pongo pygmaeus skulls. Comparisons with developmental features of the human dentition are made, and possible explanations for the formation of larger teeth within the reduced pongid growth period are discussed. The data presented in this study provide an alternative method for ageing individual pongid crania in comparative cross-sectional growth studies. The advantages of this method are demonstrated by ageing individual Gorilla crania form radiographs and plotting relative dental age against length of the jaw.

Individual radiation sensitivity (gender, age, genetic disposition). Consequences for radiation protection

International Nuclear Information System (INIS)

Streffer, C.

2013-01-01

The effects of ionising radiation on human health is influenced by a number of physiological and molecular biological factors. This is also valid for the causation of stochastic radiation effects especially the causation of cancer. Several epidemiological studies have resulted with respect to the total rate of solid cancers that women are more sensitive than men by a factor of 1.6 to 2.0. For leukaemia this is not the case. The largest studies come from the investigations on the survivors of the atomic bombs in Hiroshima and Nagasaki. But also studies on the population of the Techa River (Southeast Urals) yield such data. The analyses of single cancer localizations come to different results with respect to the dependence on the sex. Secondary cancers after radiotherapy for cancer treatment show also higher rates in women than in men. A similar situation is observed with respect to the dependence of cancer rate on age. The total rate of solid cancers is highest with children and decreases with increasing age. The effects are very different again with single cancer localizations. An especially strong age dependence was observed for thyroid cancer. Increasingly individuals have been found who are especially radiosensitive on the basis of their genetic disposition also with respect to the causation of cancer. Mechanisms and possibilities to trace these individuals are discussed. It is also discussed whether and to which extent these data should have consequences for the practical radiological protection. (orig.)

Psychiatric and Medical Conditions in Transition-Aged Individuals With ASD.

Science.gov (United States)

Davignon, Meghan N; Qian, Yinge; Massolo, Maria; Croen, Lisa A

2018-04-01

Children with autism spectrum disorder (ASD) have a variety of medical and psychiatric conditions and an increased use of health care services. There is limited information about the prevalence of psychiatric and medical conditions in adolescents and young adults with ASD. Our objective was to describe the frequency of medical and psychiatric conditions in a large population of diverse, insured transition-aged individuals with ASD. Participants included Kaiser Permanente Northern California members who were enrolled from 2013 to 2015 and who were 14 to 25 years old. Individuals with ASD ( n = 4123) were compared with peers with attention-deficit/hyperactivity disorder ( n = 20 615), diabetes mellitus ( n = 2156), and typical controls with neither condition ( n = 20 615). Over one-third (34%) of individuals with ASD had a co-occurring psychiatric condition; the most commonly reported medical conditions included infections (42%), obesity (25%), neurologic conditions (18%), allergy and/or immunologic conditions (16%), musculoskeletal conditions (15%), and gastrointestinal (11%) conditions. After controlling for sex, age, race, and duration of Kaiser Permanente Northern California membership, most psychiatric conditions were significantly more common in the ASD group than in each comparison group, and most medical conditions were significantly more common in the ASD group than in the attention-deficit/hyperactivity disorder and typical control groups but were similar to or significantly less common than the diabetes mellitus group. Although more research is needed to identify factors contributing to this excess burden of disease, there is a pressing need for all clinicians to approach ASD as a chronic health condition requiring regular follow-up and routine screening and treatment of medical and psychiatric issues. Copyright © 2018 by the American Academy of Pediatrics.

Ecstacy and cocaine : Patterns of use among prime age individuals in Amsterdam

NARCIS (Netherlands)

van Ours, J.C.

2005-01-01

This paper uses information about prime age individuals living in Amsterdam to study the patterns of use of ecstasy and cocaine.The information was collected in surveys in 1994, 1997 and 2001.The analysis shows that the use of ecstasy and cocaine is mainly influenced by calendar year, family

42 CFR 436.308 - Medically needy coverage of individuals under age 21.

Science.gov (United States)

2010-10-01

... THE VIRGIN ISLANDS Optional Coverage of the Medically Needy § 436.308 Medically needy coverage of... (b) of this section: (1) Who would not be covered under the mandatory medically needy group of... nursing facility services are provided under the plan to individuals within the age group selected under...

Cardiorespiratory fitness in 16 025 adults aged 18-91 years and associations with physical activity and sitting time

DEFF Research Database (Denmark)

Eriksen, L; Grønbaek, M; Helge, J W

2016-01-01

cardiorespiratory fitness than women, depending on age, and cardiorespiratory fitness decreased by 0.26 and 0.23 mL/min/kg per year in men and women, respectively. Cardiorespiratory fitness was higher among participants who reported a high level of physical activity in leisure time compared with participants who...... fitness was estimated in 16 025 individuals aged 18-91 years from validated cycle ergometer exercise tests. Level of leisure time physical activity (sedentary, light, moderate, and vigorous) and daily sitting time in hours was obtained from a self-administered questionnaire. Men had 20-33% higher......Our aim was to provide up-to-date cardiorespiratory fitness reference data for adults of all ages and to investigate associations between cardiores-piratory fitness and leisure time physical activity as well as sitting time. In the Danish Health Examination Survey 2007-2008, cardiorespiratory...

Individual Differences in Diurnal Preference and Time-of-Exercise Interact to Predict Exercise Frequency.

Science.gov (United States)

Hisler, Garrett C; Phillips, Alison L; Krizan, Zlatan

2017-06-01

Diurnal preference (and chronotype more generally) has been implicated in exercise behavior, but this relation has not been examined using objective exercise measurements nor have potential psychosocial mediators been examined. Furthermore, time-of-day often moderates diurnal preference's influence on outcomes, and it is unknown whether time-of-exercise may influence the relation between chronotype and exercise frequency. The current study examined whether individual differences in diurnal preference ("morningness-eveningness") predict unique variance in exercise frequency and if commonly studied psychosocial variables mediate this relation (i.e., behavioral intentions, internal exercise control, external exercise control, and conscientiousness). Moreover, the study sought to test whether individuals' typical time-of-exercise moderated the impact of diurnal preference on exercise frequency. One hundred twelve healthy adults (mean age = 25.4; SD = 11.6 years) completed baseline demographics and then wore Fitbit Zips® for 4 weeks to objectively measure exercise frequency and typical time-of-exercise. At the end of the study, participants also self-reported recent exercise. Diurnal preference predicted both self-reported exercise and Fitbit-recorded exercise frequency. When evaluating mediators, only conscientiousness emerged as a partial mediator of the relation between diurnal preference and self-reported exercise. In addition, time-of-exercise moderated diurnal preference's relation to both self-reported exercise and Fitbit-recorded exercise frequency such that diurnal preference predicted higher exercise frequency when exercise occurred at a time that was congruent with one's diurnal preference. Based on these findings, diurnal preference is valuable, above and beyond other psychological constructs, in predicting exercise frequency and represents an important variable to incorporate into interventions seeking to increase exercise.

Oral cavity infection: an adverse effect after the treatment of oral cancer in aged individuals.

Science.gov (United States)

Pan, Jie; Zhao, Jun; Jiang, Ning

2014-01-01

The immune compromised patients after treatment of oral cancer may have a chance of infection by drug-resistant opportunistic microbes. We investigated the occurrence of opportunistic microorganisms in aged individuals receiving follow-up examinations after treatment of oral cancer in China. These patients were used as test group and the respective age grouped healthy individuals as control group. In this study, the oral cavity microorganisms such as bacteria and yeast were taken for the analysis. After the screening of representative microorganisms, their aptitude of pervasiveness against drugs was studied. Here, we used antimicrobial agents which are common in clinical practice. We also performed studies to investigate the presence of toxin genes in methicillin-resistant S. aureus (MRSA). The results indicate that the prevalence of drug-resistant microbes was more pronounced in oral cancer patients after initial treatment above 70 years old. The oxacillin resistance of S. aureus isolate confirms that the prevalence of MRSA is increasing in accordance to age-factor and immune compromise in elderly patients. This study reveals the occurrence of drug-resistant opportunistic microorganisms in oral cavity after treatment for oral cancer in aged individuals. Special attention should be directed to MRSA during the treatment of oral cancer, and to realize the fact of immune compromise in elderly patients.

Revisiting Factors Associated With Screen Time Media Use: A Structural Study Among School-Aged Adolescents.

Science.gov (United States)

Ngantcha, Marcus; Janssen, Eric; Godeau, Emmanuelle; Ehlinger, Virginie; Le-Nezet, Olivier; Beck, François; Spilka, Stanislas

2018-06-01

Screen-based media overuse has been related to harmful consequences especially among children and adolescents. Given their complex interrelationships, predictors of screen time (ST) should be analyzed simultaneously rather than individually to avoid incomplete conclusions. Structural equation models were conducted to examine associations between media ST (television, video games, and computers) along with harmful consequences in adolescents' well-being, such as underweight and overweight, depression, and school failure. Predictors included individual (gender, age, and physical activity), family (structure and socioeconomic background), and substance use variables. We used the Health Behaviour in School-aged Children survey organized in 2014, including eighth- and ninth-grade students living in France (N = 3720). Students reported spending 3 hours per day in front of each media. Spending more than 2 hours behind each of those 3 media was associated with lower life satisfaction, less physical activity, active school bullying, and grade repetition. Socioeconomic status was the most important predictor of ST, whereas regular substance uses showed modest associations. The main implication of our findings is to sensitize parents and stakeholders about the limitation of ST, including their own use that adolescents are likely to mimic. Alternative measures such as off-line time should be encouraged.

Time averaging, ageing and delay analysis of financial time series

Science.gov (United States)

Cherstvy, Andrey G.; Vinod, Deepak; Aghion, Erez; Chechkin, Aleksei V.; Metzler, Ralf

2017-06-01

We introduce three strategies for the analysis of financial time series based on time averaged observables. These comprise the time averaged mean squared displacement (MSD) as well as the ageing and delay time methods for varying fractions of the financial time series. We explore these concepts via statistical analysis of historic time series for several Dow Jones Industrial indices for the period from the 1960s to 2015. Remarkably, we discover a simple universal law for the delay time averaged MSD. The observed features of the financial time series dynamics agree well with our analytical results for the time averaged measurables for geometric Brownian motion, underlying the famed Black-Scholes-Merton model. The concepts we promote here are shown to be useful for financial data analysis and enable one to unveil new universal features of stock market dynamics.

A comparison of individual and social time trade-off values for health states in the general population

DEFF Research Database (Denmark)

Burström, Kristina; Johannesson, Magnus; Diderichsen, Finn

2005-01-01

and a rating scale (RS) question were included (n=2549 for all three questions). The mean TTO (EQ-5D) value was 0.943 (0.890) in the youngest age-group and 0.699 (0.733) in the oldest age-group. The difference between TTO and EQ-5D values was greater in more severe health status groups was. The same equation......This study aimed to compare directly elicited individual time trade-off (TTO) values in a general population sample with the social values derived using the UK EQ-5D index tariff. In the Stockholm County 1998 postal Public Health Survey (n=4950, 20-88 years), the EQ-5D self-classifier, a TTO...... for the EQ-5D dimensions (pdiffer systematically and that the difference is greater the more severe the health status is. The social EQ-5D index tariff may also underestimate the severity in health status at older ages; age appears...

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

Science.gov (United States)

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

2018-01-01

While aging is generally associated with episodic memory decline, not all older adults exhibit memory loss. Furthermore, emotional memories are not subject to the same extent of forgetting and appear preserved in aging. We conducted high-resolution fMRI during a task involving pattern separation of emotional information in older adults with and without age-related memory impairment (characterized by performance on a word-list learning task: low performers: LP vs. high performers: HP). We found signals consistent with emotional pattern separation in hippocampal dentate (DG)/CA3 in HP but not in LP individuals, suggesting a deficit in emotional pattern separation. During false recognition, we found increased DG/CA3 activity in LP individuals, suggesting that hyperactivity may be associated with overgeneralization. We additionally observed a selective deficit in basolateral amygdala—lateral entorhinal cortex—DG/CA3 functional connectivity in LP individuals during pattern separation of negative information. During negative false recognition, LP individuals showed increased medial temporal lobe functional connectivity, consistent with overgeneralization. Overall, these results suggest a novel mechanistic account of individual differences in emotional memory alterations exhibited in aging. PMID:27723500

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

Science.gov (United States)

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

2017-01-01

While aging is generally associated with episodic memory decline, not all older adults exhibit memory loss. Furthermore, emotional memories are not subject to the same extent of forgetting and appear preserved in aging. We conducted high-resolution fMRI during a task involving pattern separation of emotional information in older adults with and without age-related memory impairment (characterized by performance on a word-list learning task: low performers: LP vs. high performers: HP). We found signals consistent with emotional pattern separation in hippocampal dentate (DG)/CA3 in HP but not in LP individuals, suggesting a deficit in emotional pattern separation. During false recognition, we found increased DG/CA3 activity in LP individuals, suggesting that hyperactivity may be associated with overgeneralization. We additionally observed a selective deficit in basolateral amygdala-lateral entorhinal cortex-DG/CA3 functional connectivity in LP individuals during pattern separation of negative information. During negative false recognition, LP individuals showed increased medial temporal lobe functional connectivity, consistent with overgeneralization. Overall, these results suggest a novel mechanistic account of individual differences in emotional memory alterations exhibited in aging. Copyright © 2016 Elsevier Inc. All rights reserved.

Cardiovascular evaluation of middle-aged/ senior individuals engaged in leisure-time sport activities: position stand from the sections of exercise physiology and sports cardiology of the European Association of Cardiovascular Prevention and Rehabilitation.

Science.gov (United States)

Borjesson, Mats; Urhausen, Alex; Kouidi, Evangelia; Dugmore, Dorian; Sharma, Sanjay; Halle, Martin; Heidbüchel, Hein; Björnstad, Hans Halvor; Gielen, Stephan; Mezzani, Alessandro; Corrado, Domenico; Pelliccia, Antonio; Vanhees, Luc

2011-06-01

Regular aerobic exercise at moderate intensities and an increased physical fitness are associated with a reduced risk of fatal and nonfatal coronary events in middle-aged individuals. In contrast, moderate and vigorous physical exertion is associated with an increased risk for cardiac events, including sudden cardiac death in individuals harbouring cardiovascular disease. The risk-benefit ratio may differ in relation to the individual’s age, fitness level, and presence of cardiovascular disease; sedentary individuals with underlying coronary artery disease are at greatest risk. The intention of the present position stand of the European Association of Cardiovascular Prevention and Rehabilitation is to encourage individuals to participate in regular physical activity and derive the benefits of physical exercise while minimizing the risk of cardiovascular adverse events. Therefore, the aim is to establish the most practical method of cardiovascular evaluation in middle-age/senior individuals, who are contemplating exercise or who are already engaged in nonprofessional competitive or recreational leisure sporting activity. These recommendations rely on existing scientific evidence, and in the absence of such, on expert consensus. The methodology of how middle-aged and older individuals should be evaluated appropriately before engaging in regular physical activity is both complex and controversial. On practical grounds the consensus panel recommend that such evaluation should vary according to the individual’s cardiac risk profile and the intended level of physical activity. Self assessment of the habitual physical activity level and of the risk factors, are recommended for screening of large populations. Individuals deemed to be at risk require further evaluation by a qualified physician. In senior/adult individuals with an increased risk for coronary events, maximal exercise testing (and possibly further evaluations) is advocated. Hopefully, the recommendations

Gastrointestinal mean transit times in young and middle-aged healthy subjects

DEFF Research Database (Denmark)

Graff, J; Brinch, K; Madsen, Jan Lysgård

2001-01-01

To investigate the effects of age and gender on gastric, small intestinal and colonic mean transit times, a study was conducted in 32 healthy volunteers: eight young women (22-30 years), eight young men (20-28 years), eight middle-aged women (43-51 years) and eight middle-aged men (38-53 years......, small intestinal and colonic mean transit times were calculated. The gastric, small intestinal and colonic mean transit times were significantly longer in women. Ageing was shown to accelerate the gastric and small intestinal transit significantly. In the group of men the colonic mean transit time...... was unaffected by age, but middle-aged women had a significantly slower colonic transit than young women. We therefore conclude that both age and gender have to be considered when reference values for gastric, small intestinal and colonic mean transit times have to be established....

Event-related potential indices of inter-individual and age differences in visual attention capacity

DEFF Research Database (Denmark)

Wiegand, Iris; Töllner, Thomas; Dyrholm, Mads

The ‘Theory of Visual Attention’ quantifies an individual’s capacity of attentional resources in parameters visual processing speed C and vSTM storage capacity K. By combining TVA-based assessment with neurophysiology, we showed that distinct ERP components index inter-individual differences......-related changes in attentional capacities, these ERP markers of individual differences in processing speed and storage capacity were validated in an older group. Furthermore, additional components were related to performance exclusively in older inidividuals: Anterior N1 amplitudes were reduced for slower older...... that reorganization of attentional brain networks, including age-specific decline and compensation mechanisms, determines older individuals’ attention capacity. Furthermore, we show that the distinctiveness of the two functions, as defined in TVA, is preserved (or even increased) in older age....

Individual quality and age but not environmental or social conditions modulate costs of reproduction in a capital breeder.

Science.gov (United States)

Debeffe, Lucie; Poissant, Jocelyn; McLoughlin, Philip D

2017-08-01

Costs associated with reproduction are widely known to play a role in the evolution of reproductive tactics with consequences to population and eco-evolutionary dynamics. Evaluating these costs as they pertain to species in the wild remains an important goal of evolutionary ecology. Individual heterogeneity, including differences in individual quality (i.e., among-individual differences in traits associated with survival and reproduction) or state, and variation in environmental and social conditions can modulate the costs of reproduction; however, few studies have considered effects of these factors simultaneously. Taking advantage of a detailed, long-term dataset for a population of feral horses (Sable Island, Nova Scotia, Canada), we address the question of how intrinsic (quality, age), environmental (winter severity, location), and social conditions (group size, composition, sex ratio, density) influence the costs of reproduction on subsequent reproduction. Individual quality was measured using a multivariate analysis on a combination of four static and dynamic traits expected to depict heterogeneity in individual performance. Female quality and age interacted with reproductive status of the previous year to determine current reproductive effort, while no effect of social or environmental covariates was found. High-quality females showed higher probabilities of giving birth and weaning their foal regardless of their reproductive status the previous year, while those of lower quality showed lower probabilities of producing foals in successive years. Middle-aged (prime) females had the highest probability of giving birth when they had not reproduced the year before, but no such relationship with age was found among females that had reproduced the previous year, indicating that prime-aged females bear higher costs of reproduction. We show that individual quality and age were key factors modulating the costs of reproduction in a capital breeder but that

Age-associated metabolic and morphologic changes in mitochondria of individual mouse and hamster oocytes.

Directory of Open Access Journals (Sweden)

Fatma Simsek-Duran

Full Text Available BACKGROUND: In human oocytes, as in other mammalian ova, there is a significant variation in the pregnancy potential, with approximately 20% of oocyte-sperm meetings resulting in pregnancies. This frequency of successful fertilization decreases as the oocytes age. This low proportion of fruitful couplings appears to be influenced by changes in mitochondrial structure and function. In this study, we have examined mitochondrial biogenesis in both hamster (Mesocricetus auratus and mouse (Mus musculus ova as models for understanding the effects of aging on mitochondrial structure and energy production within the mammalian oocyte. METHODOLOGY/PRINCIPAL FINDINGS: Individual metaphase II oocytes from a total of 25 young and old mice and hamsters were collected from ovarian follicles after hormone stimulation and prepared for biochemical or structural analysis. Adenosine triphosphate levels and mitochondrial DNA number were determined within individual oocytes from young and old animals. In aged hamsters, oocyte adenosine triphosphate levels and mitochondrial DNA molecules were reduced 35.4% and 51.8%, respectively. Reductions of 38.4% and 44% in adenosine triphosphate and mitochondrial genomes, respectively, were also seen in aged mouse oocytes. Transmission electron microscopic (TEM analysis showed that aged rodent oocytes had significant alterations in mitochondrial and cytoplasmic lamellae structure. CONCLUSIONS/SIGNIFICANCE: In both mice and hamsters, decreased adenosine triphosphate in aged oocytes is correlated with a similar decrease in mtDNA molecules and number of mitochondria. Mitochondria in mice and hamsters undergo significant morphological change with aging including mitochondrial vacuolization, cristae alterations, and changes in cytoplasmic lamellae.

Errors in 'BED'-derived estimates of HIV incidence will vary by place, time and age.

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Timothy B Hallett

2009-05-01

Full Text Available The BED Capture Enzyme Immunoassay, believed to distinguish recent HIV infections, is being used to estimate HIV incidence, although an important property of the test--how specificity changes with time since infection--has not been not measured.We construct hypothetical scenarios for the performance of BED test, consistent with current knowledge, and explore how this could influence errors in BED estimates of incidence using a mathematical model of six African countries. The model is also used to determine the conditions and the sample sizes required for the BED test to reliably detect trends in HIV incidence.If the chance of misclassification by BED increases with time since infection, the overall proportion of individuals misclassified could vary widely between countries, over time, and across age-groups, in a manner determined by the historic course of the epidemic and the age-pattern of incidence. Under some circumstances, changes in BED estimates over time can approximately track actual changes in incidence, but large sample sizes (50,000+ will be required for recorded changes to be statistically significant.The relationship between BED test specificity and time since infection has not been fully measured, but, if it decreases, errors in estimates of incidence could vary by place, time and age-group. This means that post-assay adjustment procedures using parameters from different populations or at different times may not be valid. Further research is urgently needed into the properties of the BED test, and the rate of misclassification in a wide range of populations.

The embodied and relational nature of the mind: implications for clinical interventions in aging individuals and populations.

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Rejeski, W Jack; Gauvin, Lise

2013-01-01

Considerable research over the past decade has garnered support for the notion that the mind is both embodied and relational. Jointly, these terms imply that the brain, physical attributes of the self, and features of our interpersonal relationships and of the environments in which we live jointly regulate energy and information flow; they codetermine how we think, feel, and behave both individually and collectively. In addition to direct experience, evidence supports the view that stimuli embedded within past memories trigger multimodal simulations throughout the body and brain to literally recreate lived experience. In this paper, we review empirical support for the concept of an embodied and relational mind and then reflect on the implications of this perspective for clinical interventions in aging individuals and populations. Data suggest that environmental influences literally "get under the skin" with aging; that musculoskeletal and visceral sensations become more prominent in activities of the mind due to aging biological systems and chronic disease. We argue that conceiving the mind as embodied and relational will grow scientific inquiry in aging, transform how we think about the self-system and well-being, and lead us to rethink health promotion interventions aimed at aging individuals and populations.

Correlates of individual, and age-related, differences in short-term learning☆

OpenAIRE

Zhang, Zhiyong; Davis, Hasker P.; Salthouse, Timothy A.; Tucker-Drob, Elliot M.

2007-01-01

Latent growth models were applied to data on multitrial verbal and spatial learning tasks from two independent studies. Although significant individual differences in both initial level of performance and subsequent learning were found in both tasks, age differences were found only in mean initial level, and not in mean learning. In neither task was fluid or crystallized intelligence associated with learning. Although there were moderate correlations among the level parameters across the verb...

Should we stop thinking about inhibition? Searching for individual and age differences in inhibition ability.

Science.gov (United States)

Rey-Mermet, Alodie; Gade, Miriam; Oberauer, Klaus

2018-04-01

Inhibition is often conceptualized as a unitary construct reflecting the ability to ignore and suppress irrelevant information. At the same time, it has been subdivided into inhibition of prepotent responses (i.e., the ability to stop dominant responses) and resistance to distracter interference (i.e., the ability to ignore distracting information). The present study investigated the unity and diversity of inhibition as a psychometric construct, and tested the hypothesis of an inhibition deficit in older age. We measured inhibition in young and old adults with 11 established laboratory tasks: antisaccade, stop-signal, color Stroop, number Stroop, arrow flanker, letter flanker, Simon, global-local, positive and negative compatibility tasks, and n-2 repetition costs in task switching. In both age groups, the inhibition measures from individual tasks had good reliabilities, but correlated only weakly among each other. Structural equation modeling identified a 2-factor model with factors for inhibition of prepotent responses and resistance to distracter interference. Older adults scored worse in the inhibition of prepotent response, but better in the resistance to distracter interference. However, the model had low explanatory power. Together, these findings call into question inhibition as a psychometric construct and the hypothesis of an inhibition deficit in older age. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Vocational Rehabilitation Service Patterns and Outcomes for Individuals with Autism of Different Ages

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Chen, June L.; Sung, Connie; Pi, Sukyeong

2015-01-01

Young adults with autism spectrum disorders (ASD) often experience employment difficulties. Using Rehabilitation Service Administration data (RSA-911), this study investigated the service patterns and factors related to the employment outcomes of individuals with ASD in different age groups. Hierarchical logistic regression analyses were conducted…

The role of time and time perspective in age-related processes: Introduction to the special issue.

Science.gov (United States)

Fung, Helene H; Isaacowitz, Derek M

2016-09-01

There currently appears to be a general consensus on the relationship between time perspective and aging, such that (a) future time is perceived as more limited with age and (b) older people are more present-focused and less future-focused than younger people. At the same time, there are debates about whether these age differences are positively related to well-being and to what extent there are boundary conditions beyond which these age differences would cease to occur. The 8 manuscripts included in this Special Issue attempt to shed light on these debates. In doing so, they refine the dominant theoretical perspective on the topic-socioemotional selectivity theory-and introduce new theoretical perspectives. New measures and methodologies for studying time perspective and aging are also discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Are larks future-oriented and owls present-oriented? Age- and sex-related shifts in chronotype-time perspective associations.

Science.gov (United States)

Nowack, Kati; van der Meer, Elke

2013-12-01

The chronotype (morningness/eveningness) relates to individual differences in circadian preferences. Time perspective (past, present, future) refers to the preference to rely on a particular temporal frame for decision-making processes and behavior. First evidence suggests that future time perspective is associated with greater morningness and present time perspective with greater eveningness. However, little is known about how chronotype-time perspective relationships may alter over the life span. This present study investigated links between chronotype and time perspective more thoroughly by taking age and sex into account as well. Seven hundred six participants aged between 17 and 74 completed German adaptations of the Morningness--Eveningness Questionnaire (MEQ) and Zimbardo Time Perspective Inventory (ZTPI). Controlling for age and sex, relationships between morningness and future time perspective as well as between eveningness and present time perspective were replicated. These findings were supported by significant associations between time perspective and midpoint of sleep. Future time perspective was linked to earlier midpoints of sleep, indicating an early chronotype. Present time perspective was associated with later midpoints of sleep, indicating a late chronotype. However, age and sex had an impact on the chronotype-time perspective relationships. In all age groups, male larks were more future-oriented and less present-oriented, male owls more present-oriented and less future-oriented. The same conclusion could be drawn for female adolescents and young adults. For female adults above 30, there was no interrelationship between morningness and future time perspective but between eveningness and past time perspective. Female adult owls were more present-oriented as well as more past-oriented. Female adult larks were less present-oriented and less past-oriented. Findings are discussed in the light of neuroendocrine and serotonergic functioning.

Individual and age-related variation in chromatic contrast adaptation

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Elliott, Sarah L.; Werner, John S.; Webster, Michael A.

2012-01-01

Precortical color channels are tuned primarily to the LvsM (stimulation of L and M cones varied, but S cone stimulation held constant) or SvsLM (stimulation of S cones varied, but L and M cone stimulation held constant) cone-opponent (cardinal) axes, but appear elaborated in the cortex to form higher-order mechanisms tuned to both cardinal and intermediate directions. One source of evidence for these higher-order mechanisms has been the selectivity of color contrast adaptation for noncardinal directions, yet the degree of this selectivity has varied widely across the small sample of observers tested in previous studies. This study explored the possible bases for this variation, and in particular tested whether it reflected age-related changes in the distribution or tuning of color mechanisms. Observers included 15 younger (18–22 years of age) and 15 older individuals (66–82), who adapted to temporal modulations along one of four chromatic axes (two cardinal and two intermediate axes) and then matched the hue and contrast of test stimuli lying along eight different directions in the equiluminant plane. All observers exhibited aftereffects that were selective for both the cardinal and intermediate directions, although selectivity was weaker for the intermediate axes. The degree of selectivity increased with the magnitude of adaptation for all axes, and thus adaptation strength alone may account for much of the variance in selectivity among observers. Older observers showed a stronger magnitude of adaptation thus, surprisingly, more conspicuous evidence for higher-order mechanisms. For both age groups the aftereffects were well predicted by response changes in chromatic channels with linear spectral sensitivities, and there was no evidence for weakened channel tuning with aging. The results suggest that higher-order mechanisms may become more exposed in observers or conditions in which the strength of adaptation is greater, and that both chromatic contrast

Leisure time physical activity participation in individuals with spinal cord injury in Malaysia: barriers to exercise.

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Mat Rosly, Maziah; Halaki, Mark; Hasnan, Nazirah; Mat Rosly, Hadi; Davis, Glen M; Husain, Ruby

2018-02-06

Cross-sectional. An epidemiological study describing leisure time physical activities (LTPA) and the associations of barriers, sociodemographic and injury characteristics to moderate-vigorous aerobic exercise participation among individuals with spinal cord injury (SCI) in a developing Southeast Asian country. SCI community in Malaysia. The study sample consisted of 70 participants with SCI. Questionnaires were distributed containing an abbreviated Physical Activity Scale for Individuals with Physical Disabilities (items 2-6) and the Barriers to Exercise Scale using a 5-tier Likert format. Statistical analyses were χ 2 tests, odds ratios, and binary forward stepwise logistic regression to assess the association and to predict factors related to participation in moderate-vigorous intensity aerobic exercise (items 4 and 5). Seventy-three percent of the study sample did not participate in any form of moderate or vigorous LTPA. The top three barriers to undertaking LTPA (strongly agree and agree descriptors) were expensive exercise equipment (54%), pain (37%) and inaccessible facilities (36%). Participants over the age of 35 years, ethnicity, health concerns, perceiving exercise as difficult and indicating lack of transport were significantly different (p exercise type of LTPA. Age, ethnicity, indicated health concerns and lack of transport were the significant predictors in likelihood of participating in moderate-vigorous LTPA (p exercising is too difficult, pain while exercising, age more than 35), interpersonal (different ethnicity), community (expensive exercise equipment), and policy levels (lack of or poor access to transportation, inaccessible facilities) that prevent LTPA participation.

Relationships between adults` participation in leisure time physical activity and demographic factors. Part I: gender and age – review and update

Directory of Open Access Journals (Sweden)

Donata Woitas-Ślubowska

2016-08-01

Full Text Available Background: The benefits of regular moderate-to-vigorous leisure-time physical activity (LTPA are well documented, and include reduced morbidity and mortality from cardiovascular disease, diabetes, cancer, depression, and other pervasive conditions. Despite these benefits, adults` participation in regular LTPA is still low. Many previous studies showed associations between adults` participation in LTPA and demographic factors but the results of these researches are inconsistent. The purpose of this study was to perform a systematic review of studies examining the relation between adults` participation in LTPA and two demographic variables: gender and age. Method: The systematic review was limited to four factors: leisure-time physical activity, adults, gender and age. Literature searches were conducted using predefined keywords in 6 key database. A total of 46 potential papers was identified. Of these 46 papers, 25 passed the eligibility criteria and were included in the systematic review. Results: In most of the analyzed studies  showed no significant differences in the percentage of inactive men and women. Among sufficient active individuals there were more men than women. In all analyzed studies found significant association between the level of LTPA and age of men and women. However, the directions of these connections were different in individual countries, and age and gender groups. Conclusion: Relationships between adults` participation in LTPA and gender, and age are specific for men and women in individual countries, and age groups, therefore there is necessity to monitor the level of LTPA in these subgroups. The results of these studies should be useful in the creation of the strategies supported adults` participation in LTPA.

Convergence in Sleep Time Accomplished? Gender Gap in Sleep Time for Middle-Aged Adults in Korea.

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Cha, Seung-Eun; Eun, Ki-Soo

2018-04-19

Although the gender gap in sleep time has narrowed significantly in the last decade, middle-aged women between ages 35 and 60 still sleep less than their male counterparts in Korea. This study examines and provides evidence for factors contributing to the gender gap in this age group. Using Korean Time Use Survey (KTUS) data from 2004, 2009 and 2014, we find that middle-aged women’s difficulty in managing work-life balance and traditional role expectations placed upon women are the main causes of the gender gap in sleep time. The decomposition analysis reveals that the improved socioeconomic status and recent changes in familial expectations for women may have helped them sleep more than in the past. However, there remain fundamental differences in attitude and time use patterns between men and women that prevent middle-aged women from getting the same amount of sleep.

Effects of aging on calibration and response time of nuclear plant pressure transmitters

International Nuclear Information System (INIS)

Hashemian, H.M.

1991-01-01

This paper presents the key results of an experimental research project conducted for the Nuclear Regulatory Commission to quantify the effects of normal aging on static and dynamic performance of nuclear grade pressure, level, and flow transmitters (hereafter referred to as pressure transmitters). The project involved laboratory testing of representative pressure transmitters manufactured by Barton, Foxboro, Rosemount, and Tobar (or Veritrak) companies. These manufacturers provide the four most commonly used pressure transmitters in the safety systems of US nuclear power plants. The transmitters were tested under normal aging conditions as opposed to accelerated aging, even though accelerated aging will be used in the last few months of the project to determine the weak links and failure modes of the transmitters. The project has been performed in two phases. The Phase 1 project which was a six month feasibility study has been completed and the results published in NUREG/CR-5383. The Phase 2 project is still underway with the final report due in the fall of 1991. The project has focused on the following areas: (1) effects of aging on calibration stability; (2) effects of aging on response time; (3) study of individual components of pressure transmitters that are sensitive to aging degradation; (4) sensing line blockages due to solidification of boron, formation of sludge, freezing, and other effects; (5) search of licensee event reports and component reliability databases for failures of safety-related pressure transmitters; and (6) oil loss syndrome in Rosemount pressure transmitters

Effects of real-time gait biofeedback on paretic propulsion and gait biomechanics in individuals post-stroke.

Science.gov (United States)

Genthe, Katlin; Schenck, Christopher; Eicholtz, Steven; Zajac-Cox, Laura; Wolf, Steven; Kesar, Trisha M

2018-04-01

Objectives Gait training interventions that target paretic propulsion induce improvements in walking speed and function in individuals post-stroke. Previously, we demonstrated that able-bodied individuals increase propulsion unilaterally when provided real-time biofeedback targeting anterior ground reaction forces (AGRF). The purpose of this study was to, for the first time, investigate short-term effects of real-time AGRF gait biofeedback training on post-stroke gait. Methods Nine individuals with post-stroke hemiparesis (6 females, age = 54 ± 12.4 years 39.2 ± 24.4 months post-stroke) completed three 6-minute training bouts on an instrumented treadmill. During training, visual and auditory biofeedback were provided to increase paretic AGRF during terminal stance. Gait biomechanics were evaluated before training, and during retention tests conducted 2, 15, and 30 minutes post-training. Primary dependent variables were paretic and non-paretic peak AGRF; secondary variables included paretic and non-paretic peak trailing limb angle, plantarflexor moment, and step length. In addition to evaluating the effects of biofeedback training on these dependent variables, we compared effects of a 6-minute biofeedback training bout to a non-biofeedback control condition. Results Compared to pre-training, significantly greater paretic peak AGRFs were generated during the 2, 15, and 30-minute retention tests conducted after the 18-minute biofeedback training session. Biofeedback training induced no significant effects on the non-paretic leg. Comparison of a 6-minute biofeedback training bout with a speed-matched control bout without biofeedback demonstrated a main effect for training type, with greater peak AGRF generation during biofeedback. Discussion Our results suggest that AGRF biofeedback may be a feasible and promising gait training strategy to target propulsive deficits in individuals post-stroke.

Influence of an individual's age on the amount and interpretability of DNA left on touched items.

Science.gov (United States)

Poetsch, Micaela; Bajanowski, Thomas; Kamphausen, Thomas

2013-11-01

In crime scene investigations, DNA left by touch on an object can be found frequently and the significant improvements in short tandem repeat (STR) amplification in recent years built up a high expectation to identify the individual(s) who touched the object by their DNA profile. Nevertheless, the percentage of reliably analysable samples varies considerably between different crime scenes even if the nature of the stains appears to be very similar. Here, it has been proposed that the amount and quality of DNA left at a crime scene may be influenced by external factors (like nature of the surface) and/or individual factors (like skin conditions). In this study, the influence of the age of an individual who left his DNA on an object is investigated. Handprints from 213 individuals (1 to 89 years old) left on a plastic syringe were analysed for DNA amount and STR alleles using Quantifiler® and PowerPlex® ESX 17. A full profile of the individual could be found in 75 % of all children up to 10 years, 9 % of adolescents (11 to 20 years), 25 % of adults (21 to 60 years) and 8 % of elderly people (older than 60 years). No person older than 80 years displayed a full profile. Drop-in and drop-out artefacts occurred frequently throughout the age groups. A dependency of quantity and quality of the DNA left on a touched object on the age of the individual could be clearly demonstrated at least for children and elderly people. An epithelial abrasion unexpectedly good to interpret may be derived from a child, whereas the suspected skin contact of an elderly person with an object may be impossible to prove.

Aging and individual differences in binding during sentence understanding: evidence from temporary and global syntactic attachment ambiguities.

Science.gov (United States)

Payne, Brennan R; Grison, Sarah; Gao, Xuefei; Christianson, Kiel; Morrow, Daniel G; Stine-Morrow, Elizabeth A L

2014-02-01

We report an investigation of aging and individual differences in binding information during sentence understanding. An age-continuous sample of adults (N=91), ranging from 18 to 81 years of age, read sentences in which a relative clause could be attached high to a head noun NP1, attached low to its modifying prepositional phrase NP2 (e.g., The son of the princess who scratched himself/herself in public was humiliated), or in which the attachment site of the relative clause was ultimately indeterminate (e.g., The maid of the princess who scratched herself in public was humiliated). Word-by-word reading times and comprehension (e.g., who scratched?) were measured. A series of mixed-effects models were fit to the data, revealing: (1) that, on average, NP1-attached sentences were harder to process and comprehend than NP2-attached sentences; (2) that these average effects were independently moderated by verbal working memory capacity and reading experience, with effects that were most pronounced in the oldest participants and; (3) that readers on average did not allocate extra time to resolve global ambiguities, though older adults with higher working memory span did. Findings are discussed in relation to current models of lifespan cognitive development, working memory, language experience, and the role of prosodic segmentation strategies in reading. Collectively, these data suggest that aging brings differences in sentence understanding, and these differences may depend on independent influences of verbal working memory capacity and reading experience. Copyright © 2013 Elsevier B.V. All rights reserved.

What’s age got to do with it? Accounting for individual factors in second language accent

Directory of Open Access Journals (Sweden)

Alene Moyer

2014-01-01

Full Text Available Empirical research conducted over the past few decades suggests that the age at which an individual is first exposed to a second language affects long-term outcomes, in particular for phonology. The question that has occupied scholars of various bents is what, exactly, underlies the robust age effects observed. Does age imply immutable changes in one’s ability to ever sound native-like? Are these changes neurological, cognitive, or socio-psychological in nature? What role do L2 use and contact play? Do age-related influences apply to all individuals, or can language learners actually chart their own course when it comes to accent? This paper will outline basic assumptions of the critical period for phonology while suggesting a different approach to the age question that highlights the individual’s role in both process and outcome. Constructs such as L2 experience, motivation, self-concept, learning approach, and willingness to communicate are discussed in depth in order to show the fundamental connection between cognition and affect so critical for late phonological learning. A re-orientation of the age research is suggested as a result, to prioritize contextual understandings of language use and learner agency.

The pace of aging: Intrinsic time scales in demography

Directory of Open Access Journals (Sweden)

Tomasz Wrycza

2014-05-01

Full Text Available Background: The pace of aging is a concept that captures the time-related aspect of aging. It formalizesthe idea of a characteristic life span or intrinsic population time scale. In the rapidly developing field of comparative biodemography, measures that account for inter-speciesdifferences in life span are needed to compare how species age. Objective: We aim to provide a mathematical foundation for the concept of pace. We derive desiredmathematical properties of pace measures and suggest candidates which satisfy these properties. Subsequently, we introduce the concept of pace-standardization, which reveals differences in demographic quantities that are not due to pace. Examples and consequences are discussed. Conclusions: Mean life span (i.e., life expectancy from birth or from maturity is intuitively appealing,theoretically justified, and the most appropriate measure of pace. Pace-standardizationprovides a serviceable method for comparative aging studies to explore differences indemographic patterns of aging across species, and it may considerably alter conclusionsabout the strength of aging.

Ageing and feature binding in visual working memory: The role of presentation time.

Science.gov (United States)

Rhodes, Stephen; Parra, Mario A; Logie, Robert H

2016-01-01

A large body of research has clearly demonstrated that healthy ageing is accompanied by an associative memory deficit. Older adults exhibit disproportionately poor performance on memory tasks requiring the retention of associations between items (e.g., pairs of unrelated words). In contrast to this robust deficit, older adults' ability to form and temporarily hold bound representations of an object's surface features, such as colour and shape, appears to be relatively well preserved. However, the findings of one set of experiments suggest that older adults may struggle to form temporary bound representations in visual working memory when given more time to study objects. However, these findings were based on between-participant comparisons across experimental paradigms. The present study directly assesses the role of presentation time in the ability of younger and older adults to bind shape and colour in visual working memory using a within-participant design. We report new evidence that giving older adults longer to study memory objects does not differentially affect their immediate memory for feature combinations relative to individual features. This is in line with a growing body of research suggesting that there is no age-related impairment in immediate memory for colour-shape binding.

Determining optimum aging time using novel core flooding equipment

DEFF Research Database (Denmark)

Ahkami, Mehrdad; Chakravarty, Krishna Hara; Xiarchos, Ioannis

2016-01-01

the optimum aging time regardless of variations in crude oil, rock, and brine properties. State of the art core flooding equipment has been developed that can be used for consistently determining the resistivity of the coreplug during aging and waterflooding using advanced data acquisition software......New methods for enhanced oil recovery are typically developed using core flooding techniques. Establishing reservoir conditions is essential before the experimental campaign commences. The realistic oil-rock wettability can be obtained through optimum aging of the core. Aging time is affected....... In the proposed equipment, independent axial and sleeve pressure can be applied to mimic stresses at reservoir conditions. 10 coreplugs (four sandstones and six chalk samples) from the North Sea have been aged for more than 408 days in total and more than 29000 resistivity data points have been measured...

Active Aging for Individuals with Intellectual Disability: Meaningful Community Participation through Employment, Retirement, Service, and Volunteerism

Science.gov (United States)

Fesko, Sheila Lynch; Hall, Allison Cohen; Quinlan, Jerrilyn; Jockell, Catherine

2012-01-01

As individuals with intellectual and developmental disabilities become more engaged in community employment, it will be critical to consider how their employment experience changes as they age. Similar to other seniors, individuals will need to consider whether they want to maintain their employment, reduce their work commitment, or retire…

Part-time sick leave as a treatment method for individuals with musculoskeletal disorders.

Science.gov (United States)

Andrén, Daniela; Svensson, Mikael

2012-09-01

There is increasing evidence that staying active is an important part of a recovery process for individuals on sick leave due to musculoskeletal disorders (MSDs). It has been suggested that using part-time sick-leave rather than full-time sick leave will enhance the possibility of full recovery to the workforce, and several countries actively favor this policy. The aim of this paper is to examine if it is beneficial for individuals on sick leave due to MSDs to be on part-time sick leave compared to full-time sick leave. A sample of 1,170 employees from the RFV-LS (register) database of the Social Insurance Agency of Sweden is used. The effect of being on part-time sick leave compared to full-time sick leave is estimated for the probability of returning to work with full recovery of lost work capacity. A two-stage recursive bivariate probit model is used to deal with the endogeneity problem. The results indicate that employees assigned to part-time sick leave do recover to full work capacity with a higher probability than those assigned to full-time sick leave. The average treatment effect of part-time sick leave is 25 percentage points. Considering that part-time sick leave may also be less expensive than assigning individuals to full-time sick leave, this would imply efficiency improvements from assigning individuals, when possible, to part-time sick leave.

Multiple age components in individual molybdenite grains

Science.gov (United States)

Aleinikoff, John N.; Creaser, Robert A.; Lowers, Heather; Magee, Charles W.; Grauch, Richard I.

2012-01-01

Re–Os geochronology of fractions composed of unsized, coarse, and fine molybdenite from a pod of unusual monazite–xenotime gneiss within a granulite facies paragneiss, Hudson Highlands, NY, yielded dates of 950.5 ± 2.5, 953.8 ± 2.6, and 941.2 ± 2.6 Ma, respectively. These dates are not recorded by co-existing zircon, monazite, or xenotime. SEM–BSE imagery of thin sections and separated grains reveals that most molybdenite grains are composed of core and rim plates that are approximately perpendicular. Rim material invaded cores, forming irregular contacts, probably reflecting dissolution/reprecipitation. EPMA and LA-ICP-MS analyses show that cores and rims have different trace element concentrations (for example, cores are relatively enriched in W). On the basis of inclusions of zircon with metamorphic overgrowths, we conclude that molybdenite cores and rims formed after high-grade regional metamorphism. The discovery of cores and rims in individual molybdenite grains is analogous to multi-component U-Pb geochronometers such as zircon, monazite, and titanite; thus, molybdenite should be carefully examined before dating to ensure that the requirement of age homogeneity is fulfilled.

Individual and environmental correlates of objectively measured sedentary time in Dutch and Belgian adults.

Directory of Open Access Journals (Sweden)

Femke van Nassau

Full Text Available As the detrimental health effects of sedentary behaviour are well established, insight into the individual and environmental factors that influence adults' sedentary behaviour is needed. Most studies to date rely on self-reported measures of sedentary time. Therefore, the aim of the current study was to examine individual and environmental correlates of objectively measured sedentary time in Dutch and Belgian adults. Between March and August 2014, Belgian (n = 133 and Dutch (n = 223 adults, recruited as sub-sample of the SPOTLIGHT survey, wore an ActiGraph accelerometer to provide objectively measured sedentary and moderate to vigorous physical activity time. Participants completed a questionnaire assessing sociodemographic (country of residence, age, gender and educational level, lifestyle (sleep, smoking, sugar-containing beverage consumption, alcohol intake, health (body mass index, self-rated health, work (employment status and type of work, happiness, physical environmental (owning a car, number of screens, socioeconomic status and residential density and social environmental factors (social network, social cohesion. Univariate and multivariable regression analyses showed that Belgian participants had a lower odds of being sedentary for at least 9 hours per day compared to Dutch participants. Women, older participants and those meeting the WHO recommendation for physical activity were also less likely to sit for 9 hours or more per day. Participants doing (heavy manual work or being in education, homemaker, unemployed had lower odds of being sedentary for at least 9 hours per day compared to participants with a sitting job. Those with a higher self-reported social network also had lower odds for sedentary time. No associations between physical and other social environmental characteristics and sedentary time were found. Our findings add to the growing evidence of factors associated with prolonged sedentary time in adults. These findings may

The effects of marital status on episodic and semantic memory in healthy middle-aged and old individuals.

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Mousavi-Nasab, S-M-Hossein; Kormi-Nouri, Reza; Sundström, Anna; Nilsson, Lars-Göran

2012-02-01

The present study examined the influences of marital status on different episodic and semantic memory tasks. A total of 1882 adult men and women participated in a longitudinal project (Betula) on memory, health and aging. The participants were grouped into two age cohorts, 35-60 and 65-85, and studied over a period of 5 years. Episodic memory tasks concerned recognition and recall, whereas semantic memory tasks concerned knowledge and fluency. The results showed, after controlling for education, some diseases, chronological age and leisure activity as covariates, that there were significant differences between married and single individuals in episodic memory, but not in semantic memory. Married people showed significantly better memory performances than singles in both subsystems of episodic memory, that is, recall and recognition. Also, the rate of decline in episodic memory was significantly larger for singles and widowed than other groups over the 5-year time period in both age groups. The findings demonstrate that the positive relation found between marriage and health can be extended to the relation between marriage and cognitive performance. This effect might be explained by the role played by cognitive stimulation in memory and cognition. © 2011 The Authors. Scandinavian Journal of Psychology © 2011 The Scandinavian Psychological Associations.

Genetic variants of age at menopause are not related to timing of ovarian failure in breast cancer survivors.

Science.gov (United States)

Homer, Michael V; Charo, Lindsey M; Natarajan, Loki; Haunschild, Carolyn; Chung, Karine; Mao, Jun J; DeMichele, Angela M; Su, H Irene

2017-06-01

To determine if interindividual genetic variation in single-nucleotide polymorphisms (SNPs) related to age at natural menopause is associated with risk of ovarian failure in breast cancer survivors. A prospective cohort of 169 premenopausal breast cancer survivors recruited at diagnosis with stages 0 to III disease were followed longitudinally for menstrual pattern via self-reported daily menstrual diaries. Participants were genotyped for 13 SNPs previously found to be associated with age at natural menopause: EXO1, TLK1, HELQ, UIMC1, PRIM1, POLG, TMEM224, BRSK1, and MCM8. A risk variable summed the total number of risk alleles in each participant. The association between individual genotypes, and also the risk variable, and time to ovarian failure (>12 months of amenorrhea) was tested using time-to-event methods. Median age at enrollment was 40.5 years (range 20.6-46.1). The majority of participants were white (69%) and underwent chemotherapy (76%). Thirty-eight participants (22%) experienced ovarian failure. None of the candidate SNPs or the summary risk variable was significantly associated with time to ovarian failure. Sensitivity analysis restricted to whites or only to participants receiving chemotherapy yielded similar findings. Older age, chemotherapy exposure, and lower body mass index were related to shorter time to ovarian failure. Thirteen previously identified genetic variants associated with time to natural menopause were not related to timing of ovarian failure in breast cancer survivors.

Profound vision loss impairs psychological well-being in young and middle-aged individuals.

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Garcia, Giancarlo A; Khoshnevis, Matin; Gale, Jesse; Frousiakis, Starleen E; Hwang, Tiffany J; Poincenot, Lissa; Karanjia, Rustum; Baron, David; Sadun, Alfredo A

2017-01-01

The aim of this study was to evaluate the effects of profound vision loss on psychological well-being in adolescents, young adults, and middle-aged adults with regard to mood, interpersonal interactions, and career-related goals. In addition, we assessed the significance of the resources that may be used to enhance psychological well-being in cases of profound vision loss, and in particular, examined the utility of low vision aids and the role of the ophthalmologist as a provider of emotional support. A questionnaire was issued to individuals aged 13-65 years with profound vision loss resulting from Leber's hereditary optic neuropathy (LHON). Depression prevalence was evaluated with questions regarding major depressive disorder symptomatology. Participants appraised the effects of vision loss on their interpersonal interactions and career goals by providing an impact rating (IR) on a 21-point psychometric scale from -10 to +10. Social well-being index was defined as the average of interpersonal IR and career IR. Subjects were additionally asked about the use of low vision aids and sources of emotional support. A total of 103 participants (mean age =26.4±11.2 years at LHON diagnosis; mean ± standard deviation) completed the questionnaire. Nearly half (49.5%) met the depression criteria after vision loss. Negative impacts on interpersonal interactions (median IR = -5) and career goals (median IR = -6) were observed; both ratings were worse ( P negative interpersonal IR and career IR. Sixty-eight percent of subjects used electronic vision aids; controlling for age, social well-being index was higher among these individuals than for those who did not use electronic aids ( P =0.03). Over half of the participants (52.4%) asserted that they derived emotional support from their ophthalmologist. Profound vision loss in adolescents, young adults, and middle-aged adults is associated with significant negative psychological and psychosocial effects, which are influenced by

Psychological well-being among individuals aging with HIV: the value of social relationships.

Science.gov (United States)

Mavandadi, Shahrzad; Zanjani, Faika; Ten Have, Thomas R; Oslin, David W

2009-05-01

Utilizing a heterogenous sample of adults diagnosed with HIV infection, the current study sought to explore associations among age, various dimensions of social support, and psychological and functional well-being. Cross-sectional data capturing subjective and instrumental support, social interaction, behavioral health service utilization, and psychological well-being (ie, positive affect and depressive symptomatology), and physical functioning, were collected from 109 men and women living with HIV. To explore age group differences, participants were stratified by age (social interaction. However, older adults reported higher subjective support, which in turn was associated with lower depressive symptomatology, greater positive affect, and nonutilization of behavioral health services. More attention should be paid to the social environment of individuals diagnosed with HIV as the quality of social relationships may be particularly important for successful psychological adaptation to HIV.

Of goals and habits: Age-related and individual differences in goal-directed decision-making

Directory of Open Access Journals (Sweden)

Ben eEppinger

2013-12-01

Full Text Available In this study we investigated age-related and individual differences in habitual (model-free and goal-directed (model-based decision-making. Specifically, we were interested in three questions. First, does age affect the balance between model-based and model-free decision mechanisms? Second, are these age-related changes due to age differences in working memory (WM capacity? Third, can model-based behavior be affected by manipulating the distinctiveness of the reward value of choice options? To answer these questions we used a two-stage Markov decision task in in combination with computational modeling to dissociate model-based and model-free decision mechanisms. To affect model-based behavior in this task we manipulated the distinctiveness of reward probabilities of choice options. The results show age-related deficits in model-based decision-making, which are particularly pronounced if unexpected reward indicates the need for a shift in decision strategy. In this situation younger adults explore the task structure, whereas older adults show perseverative behavior. Consistent with previous findings, these results indicate that older adults have deficits in the representation and updating of expected reward value. We also observed substantial individual differences in model-based behavior. In younger adults high WM capacity is associated with greater model-based behavior and this effect is further elevated when reward probabilities are more distinct. However, in older adults we found no effect of WM capacity. Moreover, age differences in model-based behavior remained statistically significant, even after controlling for WM capacity. Thus, factors other than decline in WM, such as deficits in the in the integration of expected reward value into strategic decisions may contribute to the observed impairments in model-based behavior in older adults.

42 CFR 435.222 - Individuals under age 21 who meet the income and resource requirements of AFDC.

Science.gov (United States)

2010-10-01

... THE STATES, DISTRICT OF COLUMBIA, THE NORTHERN MARIANA ISLANDS, AND AMERICAN SAMOA Options for... adoptions subsidized in full or in part by a public agency. (3) Individuals in nursing facilities when nursing facility services are provided under the plan to individuals within the age group selected under...

Enhancement of individual differences in proliferation and differentiation potentials of aged human adipose-derived stem cells

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Mika Kawagishi-Hotta

2017-06-01

Conclusions: This study demonstrated age-related changes in the potentials of ASCs and revealed that the individual differences of ASCs become significant in people over 60 years of age (for females over 60, and for males over 80. We believe that it is important to carefully observe ASC potentials in order to achieve effective regenerative medicine treatments using ASCs.

Aging and Network Properties: Stability Over Time and Links with Learning during Working Memory Training

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Alexandru D. Iordan

2018-01-01

Full Text Available Growing evidence suggests that healthy aging affects the configuration of large-scale functional brain networks. This includes reducing network modularity and local efficiency. However, the stability of these effects over time and their potential role in learning remain poorly understood. The goal of the present study was to further clarify previously reported age effects on “resting-state” networks, to test their reliability over time, and to assess their relation to subsequent learning during training. Resting-state fMRI data from 23 young (YA and 20 older adults (OA were acquired in 2 sessions 2 weeks apart. Graph-theoretic analyses identified both consistencies in network structure and differences in module composition between YA and OA, suggesting topological changes and less stability of functional network configuration with aging. Brain-wide, OA showed lower modularity and local efficiency compared to YA, consistent with the idea of age-related functional dedifferentiation, and these effects were replicable over time. At the level of individual networks, OA consistently showed greater participation and lower local efficiency and within-network connectivity in the cingulo-opercular network, as well as lower intra-network connectivity in the default-mode network and greater participation of the somato-sensorimotor network, suggesting age-related differential effects at the level of specialized brain modules. Finally, brain-wide network properties showed associations, albeit limited, with learning rates, as assessed with 10 days of computerized working memory training administered after the resting-state sessions, suggesting that baseline network configuration may influence subsequent learning outcomes. Identification of neural mechanisms associated with learning-induced plasticity is important for further clarifying whether and how such changes predict the magnitude and maintenance of training gains, as well as the extent and limits of

Global investigation of composition and interaction networks in gut microbiomes of individuals belonging to diverse geographies and age-groups.

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Yadav, Deepak; Ghosh, Tarini Shankar; Mande, Sharmila S

2016-01-01

Factors like ethnicity, diet and age of an individual have been hypothesized to play a role in determining the makeup of gut microbiome. In order to investigate the gut microbiome structure as well as the inter-microbial associations present therein, we have performed a comprehensive global comparative profiling of the structure (composition, relative heterogeneity and diversity) and the inter-microbial networks in the gut microbiomes of 399 individuals of eight different nationalities. The study identified certain geography-specific trends with respect to composition, intra-group heterogeneity and diversity of the gut microbiomes. Interestingly, the gut microbial association/mutual-exlusion networks were observed to exhibit several cross-geography trends. It was seen that though the composition of gut microbiomes of the American and European individuals were similar, there were distinct patterns in their microbial interaction networks. Amongst European gut-microbiomes, the co-occurrence network obtained for the Danish population was observed to be most dense. Distinct patterns were also observed within Chinese, Japanese and Indian datasets. While performing an age-wise comparison, it was observed that the microbial interactions increased with the age of individuals. Furthermore, certain bacterial groups were identified to be present only in the older age groups. The trends observed in gut microbial networks could be due to the inherent differences in the diet of individuals belonging to different nationalities. For example, the higher number of microbial associations in the Danish population as compared to the Spanish population, may be attributed to the evenly distributed diet of the later. This is in line with previously reported findings which indicate an increase in functional interdependency of microbes in individuals with higher nutritional status. To summarise, the present study identifies geography and age specific patterns in the composition as well as

The roles of chronological age and time perspective in memory positivity.

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Kan, Irene P; Garrison, Shaina L; Drummey, Anna B; Emmert, Brian E; Rogers, Leeland L

2018-07-01

The observation that older adults show enhanced cognition for emotionally positive information has been labeled the positivity effect (Reed, Chan, & Mikels, 2014). According to the Socioemotional Selectivity Theory (SST, Carstensen, 1991), a prominent lifespan development theory, cognition is strongly influenced by motivational goals, and these goals are impacted by subjective time perspective. Although the positivity effect is most commonly observed in older adults, as age usually co-varies with time perspective, the SST posits that time perspective, not age, is the key explanatory factor of positivity. We examined the effects of these predictors on positivity in an episodic memory task in younger and older adults and found that age, not time perspective, was a key predictor of memory positivity. Our results add to the growing literature that challenge the notion that time perspective is the driving force behind age-related differences in emotional processing and functioning.

[Forensic age determination in living individuals at the Institute of Legal Medicine in Berlin (Charité): analysis of the expert reports from 2001 to 2007].

Science.gov (United States)

Schmidt, Sven; Knüfermann, Raidun; Tsokos, Michael; Schmeling, Andreas

2009-01-01

The analysis included the age reports provided by the Institute of Legal Medicine in Berlin (Charité) in the period from 2001 to 2007. A total of 416 age estimations were carried out, 289 in criminal and 127 in civil proceedings. 357 of the examined individuals were male, 59 were female. The vast majority of the individuals came from Vietnam. In 112 cases, there were no deviations between the indicated age and the estimated minimum age, while the actual age of the individuals was partly clearly above the estimated age. In 300 cases, there were discrepancies of up to 11 years between the indicated age and the estimated age. The study demonstrates that forensic age estimation in living individuals can make an important contribution to legal certainty.

A new quantitative evaluation method for age-related changes of individual pigmented spots in facial skin.

Science.gov (United States)

Kikuchi, K; Masuda, Y; Yamashita, T; Sato, K; Katagiri, C; Hirao, T; Mizokami, Y; Yaguchi, H

2016-08-01

Facial skin pigmentation is one of the most prominent visible features of skin aging and often affects perception of health and beauty. To date, facial pigmentation has been evaluated using various image analysis methods developed for the cosmetic and esthetic fields. However, existing methods cannot provide precise information on pigmented spots, such as variations in size, color shade, and distribution pattern. The purpose of this study is the development of image evaluation methods to analyze individual pigmented spots and acquire detailed information on their age-related changes. To characterize the individual pigmented spots within a cheek image, we established a simple object-counting algorithm. First, we captured cheek images using an original imaging system equipped with an illumination unit and a high-resolution digital camera. The acquired images were converted into melanin concentration images using compensation formulae. Next, the melanin images were converted into binary images. The binary images were then subjected to noise reduction. Finally, we calculated parameters such as the melanin concentration, quantity, and size of individual pigmented spots using a connected-components labeling algorithm, which assigns a unique label to each separate group of connected pixels. The cheek image analysis was evaluated on 643 female Japanese subjects. We confirmed that the proposed method was sufficiently sensitive to measure the melanin concentration, and the numbers and sizes of individual pigmented spots through manual evaluation of the cheek images. The image analysis results for the 643 Japanese women indicated clear relationships between age and the changes in the pigmented spots. We developed a new quantitative evaluation method for individual pigmented spots in facial skin. This method facilitates the analysis of the characteristics of various pigmented facial spots and is directly applicable to the fields of dermatology, pharmacology, and esthetic

Older job seekers' job search intensity : the interplay of proactive personality, age and occupational future time perspective

NARCIS (Netherlands)

Zacher, Hannes

2013-01-01

Long-term unemployment of older people can have severe consequences for individuals, communities and ultimately economies, and is therefore a serious concern in countries with an ageing population. However, the interplay of chronological age and other individual difference characteristics in

Cognitive functions in middle aged individuals are related to metabolic disturbances and aerobic capacity: a cross-sectional study.

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Maria Pedersen

Full Text Available AIMS: Metabolic disturbances may contribute to cognitive dysfunction in patients with type 2 diabetes. We investigated the relation between cognitive impairment and metabolic deteriorations, low physical fitness, low-grade inflammation and abdominal obesity in middle aged individuals. METHODS: We conducted a cross-sectional study including 40 to 65 year-old patients with type 2 diabetes and limited co morbidity (N = 56, age-matched individuals with impaired glucose tolerance (N = 56 as well as age-matched controls with normal glucose tolerance (N = 72. Specific cognitive functions were assessed with focus on verbal memory, processing speed, executive functions, and a composite overall mean score. Oral glucose tolerance test, VO(2max test, systemic inflammation, DXA scanning and abdominal MRI were measured. RESULTS: Multiple linear regression analyses adjusting for age, gender and verbal intelligence demonstrated that a low score in processing speed, executive functions and overall cognitive function were related to high fasting C-peptide, as well as low insulin sensitivity, beta-cell function and VO(2max. Measurements of blood glucose, obesity and inflammation were not associated with cognitive function. CONCLUSION: Low cognitive scores are seen in middle aged individuals with hyperinsulinemia, low insulin sensitivity, beta-cell function and low aerobic capacity. These findings emphasize the importance of appropriate lifestyle and not only blood glucose control in prevention of cognitive disability.

Chinese L1 children's English L2 verb morphology over time: individual variation in long-term outcomes.

Science.gov (United States)

Paradis, Johanne; Tulpar, Yasemin; Arppe, Antti

2016-05-01

This study examined accuracy in production and grammaticality judgements of verb morphology by eighteen Chinese-speaking children learning English as a second language (L2) followed longitudinally from four to six years of exposure to English, and who began to learn English at age 4;2. Children's growth in accuracy with verb morphology reached a plateau by six years, where 11/18 children did not display native-speaker levels of accuracy for one or more morphemes. Variation in children's accuracy with verb morphology was predicted by their English vocabulary size and verbal short-term memories primarily, and quality and quantity of English input at home secondarily. This study shows that even very young L2 learners might not all catch up to native speakers in this time frame and that non-age factors play a role in determining individual variation in child L2 learners' long-term outcomes with English morphology.

Reliability of Interaural Time Difference-Based Localization Training in Elderly Individuals with Speech-in-Noise Perception Disorder.

Science.gov (United States)

Delphi, Maryam; Lotfi, M-Yones; Moossavi, Abdollah; Bakhshi, Enayatollah; Banimostafa, Maryam

2017-09-01

Previous studies have shown that interaural-time-difference (ITD) training can improve localization ability. Surprisingly little is, however, known about localization training vis-à-vis speech perception in noise based on interaural time difference in the envelope (ITD ENV). We sought to investigate the reliability of an ITD ENV-based training program in speech-in-noise perception among elderly individuals with normal hearing and speech-in-noise disorder. The present interventional study was performed during 2016. Sixteen elderly men between 55 and 65 years of age with the clinical diagnosis of normal hearing up to 2000 Hz and speech-in-noise perception disorder participated in this study. The training localization program was based on changes in ITD ENV. In order to evaluate the reliability of the training program, we performed speech-in-noise tests before the training program, immediately afterward, and then at 2 months' follow-up. The reliability of the training program was analyzed using the Friedman test and the SPSS software. Significant statistical differences were shown in the mean scores of speech-in-noise perception between the 3 time points (P=0.001). The results also indicated no difference in the mean scores of speech-in-noise perception between the 2 time points of immediately after the training program and 2 months' follow-up (P=0.212). The present study showed the reliability of an ITD ENV-based localization training in elderly individuals with speech-in-noise perception disorder.

Individual risk factors for Mycoplasma hyopneumoniae infections in suckling pigs at the age of weaning

Science.gov (United States)

2013-01-01

Background In recent years, the occurrence and the relevance of Mycoplasma hyopneumoniae infections in suckling pigs has been examined in several studies. Whereas most of these studies were focused on sole prevalence estimation within different age groups, follow-up of infected piglets or assessment of pathological findings, none of the studies included a detailed analysis of individual and environmental risk factors. Therefore, the aim of the present study was to investigate the frequency of M. hyopneumoniae infections in suckling pigs of endemically infected herds and to identify individual risk factors potentially influencing the infection status of suckling pigs at the age of weaning. Results The animal level prevalence of M. hyopneumoniae infections in suckling pigs examined in three conventional pig breeding herds was 3.6% (41/1127) at the time of weaning. A prevalence of 1.2% was found in the same pigs at the end of their nursery period. In a multivariable Poisson regression model it was found that incidence rate ratios (IRR) for suckling pigs are significantly lower than 1 when teeth grinding was conducted (IRR: 0.10). Moreover, high temperatures in the piglet nest during the first two weeks of life (occasionally >40°C) were associated with a decrease of the probability of an infection (IRR: 0.23-0.40). Contrary, the application of PCV2 vaccines to piglets was associated with an increased infection risk (IRR: 9.72). Conclusions Since single infected piglets are supposed to act as initiators for the transmission of this pathogen in nursery and fattening pigs, the elimination of the risk factors described in this study should help to reduce the incidence rate of M. hyopneumoniae infections and thereby might contribute to a reduced probability of high prevalences in older pigs. PMID:23731650

Indicators of a balanced long-term service and support system: examining the impact on individuals aging with a lifelong disability.

Science.gov (United States)

Ruiz, Sarah; Urdapilleta, Oswaldo; Clark-Shirley, Leanne J; Howard, Jennifer; Poey, Judith

2012-01-01

This article explores how rebalancing efforts can support the needs of individuals aging with a lifelong disability. The National Balancing Indicator project examined the overall long-term supports and services system (LTSS) progress in five indicators within the Sustainability, Coordination and Transparency, and Prevention principles toward a balanced LTSS system for those aging with a lifelong disability. In assessing state efforts to create a balanced participant-directed LTSS system with the National Balancing Indicators, the findings suggest states are better equipping the system to handle a burgeoning population of individuals aging with a lifelong disability, but more progress is still needed. Overall, states need to continue to create a seamless system that allows individuals with lifelong disabilities to transition smoothly through the life course.

Gastrointestinal mean transit times in young and middle-aged healthy subjects

DEFF Research Database (Denmark)

Graff, J; Brinch, K; Madsen, Jan Lysgård

2001-01-01

To investigate the effects of age and gender on gastric, small intestinal and colonic mean transit times, a study was conducted in 32 healthy volunteers: eight young women (22-30 years), eight young men (20-28 years), eight middle-aged women (43-51 years) and eight middle-aged men (38-53 years......). After ingestion of a meal containing 111Indium-labelled water and 99mTechnetium-labelled omelette imaging of the abdomen was performed at intervals of 30 min until all radioactivity was located in the colon and henceforth at intervals of 24 h until all radioactivity had cleared from the colon. Gastric......, small intestinal and colonic mean transit times were calculated. The gastric, small intestinal and colonic mean transit times were significantly longer in women. Ageing was shown to accelerate the gastric and small intestinal transit significantly. In the group of men the colonic mean transit time...

Effect of aging time and aging temperature on fatigue and fracture behavior of 6063 aluminum alloy under seawater influence

International Nuclear Information System (INIS)

Siddiqui, R.A.; Abdul-Wahab, S.A.; Pervez, T.

2008-01-01

This paper describes experimentally the effect of seawater corrosion, aging time, and aging temperature on the fatigue resistance property of 6063 aluminum alloy. The 6063 aluminum alloy that was used for the study was heat treated and soaked in seawater for different intervals of time between 2 and 30 weeks. It was found that the maximum fatigue resistance property in the 6063 aluminum alloy was observed when aged between 7 and 9 h and heat treated at temperatures between 160 o C and 200 o C. Generally at constant load, the results indicated that the number of cycles to fail the 6063 aluminum alloy decreased with increasing the soaking time in seawater. Moreover, fracture surfaces were considered and studied under a scanning electron microscope (SEM). The results showed that the brittle fracture pattern tended to occur with the increase in aging time and temperature. The fatigue striations were observed very clearly at low and peak aging temperature. The increase in the fatigue resistance property with aging time was linked with the vacancies assisted diffusion mechanism and also by the hindering of dislocation movement by impure atoms

Impact of comorbidity and ageing on health-related quality of life in HIV-positive and HIV-negative individuals

NARCIS (Netherlands)

Langebeek, Nienke; Kooij, Katherine W.; Wit, Ferdinand W.; Stolte, Ineke G.; Sprangers, Mirjam A. G.; Reiss, Peter; Nieuwkerk, Pythia T.

2017-01-01

HIV-infected individuals may be at risk for the premature onset of age-associated noncommunicable comorbidities. Being HIV-positive, having comorbidities and being of higher age may adversely impact health-related quality of life (HRQL). We investigated the possible contribution of HIV infection,

Advanced age, cardiovascular risk burden, and timed up and go test performance in Parkinson disease.

Science.gov (United States)

Kotagal, Vikas; Albin, Roger L; Müller, Martijn L T M; Koeppe, Robert A; Studenski, Stephanie; Frey, Kirk A; Bohnen, Nicolaas I

2014-12-01

Cardiovascular comorbidities are a known risk factor for impaired mobility in elderly individuals. Motor impairments in Parkinson disease are conventionally ascribed to nigrostriatal dopaminergic denervation although progressive gait and balance impairments become more common with aging and often show limited response to dopaminergic replacement therapies. We explored the association between elevated cardiovascular risk factors and performance on the Timed Up and Go test in cross-sectional of Parkinson disease subjects (n = 83). Cardiovascular risk factor status was estimated using the Framingham General Cardiovascular Disease risk-scoring algorithm in order to dichotomize the cohort into those with and without elevated modifiable cardiovascular risk compared with normative scores for age and gender. All subjects underwent clinical and neuroimaging evaluations including a 3-m Timed Up and Go test, [(11)C]dihydrotetrabenazine positron emission tomography imaging to estimate nigrostriatal dopamine terminal loss, and an magnetic resonance imaging assessment of leukoaraiosis. A similar analysis was performed in 49 healthy controls. After adjusting for disease duration, leukoaraiosis, and nigrostriatal dopaminergic denervation, Parkinson disease subjects with elevated Framingham risk scores (n = 61) displayed slower Timed Up and Go test performance (β = 1.86, t = 2.41, p = .018) compared with subjects with normal range Framingham risk scores (n = 22). When age ≥65 was added to the model in a post hoc analysis, the strength of effect seen with older age (β = 1.51, t = 2.44, p = .017) was similar to that of elevated Framingham risk scoring (β = 1.87, t = 2.51, p = .014). In a multivariable regression model studying the healthy control population, advanced age (t = 2.15, p = .037) was a significant predictor of Timed Up and Go speed though striatal [(11)C]dihydrotetrabenazine (t = -1.30, p = .19) and elevated Framingham risk scores (t = 1.32, p = .19) were not

Spatiotemporal and plantar pressure patterns of 1000 healthy individuals aged 3-101 years.

Science.gov (United States)

McKay, Marnee J; Baldwin, Jennifer N; Ferreira, Paulo; Simic, Milena; Vanicek, Natalie; Wojciechowski, Elizabeth; Mudge, Anita; Burns, Joshua

2017-10-01

The purpose of this study was to establish normative reference values for spatiotemporal and plantar pressure parameters, and to investigate the influence of demographic, anthropometric and physical characteristics. In 1000 healthy males and females aged 3-101 years, spatiotemporal and plantar pressure data were collected barefoot with the Zeno™ walkway and Emed ® platform. Correlograms were developed to visualise the relationships between widely reported spatiotemporal and pressure variables with demographic (age, gender), anthropometric (height, mass, waist circumference) and physical characteristics (ankle strength, ankle range of motion, vibration perception) in children aged 3-9 years, adolescents aged 10-19 years, adults aged 20-59 years and older adults aged over 60 years. A comprehensive catalogue of 31 spatiotemporal and pressure variables were generated from 1000 healthy individuals. The key findings were that gait velocity was stable during adolescence and adulthood, while children and older adults walked at a comparable slower speed. Peak pressures increased during childhood to older adulthood. Children demonstrated highest peak pressures beneath the rearfoot whilst adolescents, adults and older adults demonstrated highest pressures at the forefoot. Main factors influencing spatiotemporal and pressure parameters were: increased age, height, body mass and waist circumference, as well as ankle dorsiflexion and plantarflexion strength. This study has established whole of life normative reference values of widely used spatiotemporal and plantar pressure parameters, and revealed changes to be expected across the lifespan. Copyright © 2017 Elsevier B.V. All rights reserved.

Your Aging Eyes: How You See as Time Goes By

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Self-rating of daily time management in children: psychometric properties of the Time-S.

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Sköld, Annika; Janeslätt, Gunnel Kristina

2017-05-01

Impaired ability to manage time has been shown in several diagnoses common in childhood. Impaired ability involves activities and participation domain (daily time management, DTM) and body function and structure domain (time-processing ability, TPA). DTM needs to be evaluated from an individual's own perspective. To date, there has been a lack of self-rating instruments for children that focus on DTM. The aim of this study is to describe psychometric properties of Time-S when used in children aged 10-17 years with a diagnosis of ADHD, Autism, CP or mild ID. Further, to test whether TPA correlates with self-rated DTM. Eighty-three children aged 10-17 years participated in the study. Rasch analysis was used to assess psychometric properties. Correlation analysis was performed between Time-S and a measure of TPA. The 21 items of the Time-S questionnaire fit into a unitary construct measuring self-perceived daily management of an individual's time. A non-significant, small correlation was found between TPA and DTM. The results indicate good psychometric properties for the questionnaire. The questionnaire is potentially useful in intervention planning and evaluation.

Snacking now or later? Individual differences in following intentions or habits explained by time perspective.

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Onwezen, M C; Van 't Riet, J; Dagevos, H; Sijtsema, S J; Snoek, H M

2016-12-01

Even when individuals are aware of long-term health effects of their diet, and form healthy intentions, they often engage in relatively unhealthy snacking habits. Some individuals fall back on unhealthy habits more easily than others. We aim to explore whether time perspective can explain why some individuals are more prone to rely on habits and others on intentions. Study 1 (N = 1503) provides a first exploration of the role of time perspective by exploring individual differences in perception of long-term and short-term consequences. In accordance with our hypotheses, Study 1 shows that habits are associated with short-term consequences and intentions with long-term consequences. Study 2 (N = 1497) shows that the effects of habits on snacking behaviour are strengthened by a present time perspective, whereas the effects of intentions on snacking behaviour are strengthened by a future time perspective. These findings imply that there is a fundamental difference in the guiding function of intentions and habits which might explain individual differences in following intentions versus habits. Individuals with a long-term perspective are more inclined to follow intentions and individuals with a short-term perspective are more inclined to follow habits. Copyright © 2016 Elsevier Ltd. All rights reserved.

individual vs. collective behavior: an experimental. investigation of risk and time preferences in couples

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Abdellaoui, Mohammed; l'Haridon, Olivier; Paraschiv, Corina

2010-01-01

Author's abstract. This paper study decision-making under risk and decision-making over time made by couples. We performed a joint experimental elicitation of risk and time preferences both for couples and for their individual members. We used general behavioral models of decision under risk and over time and measured utility, probability weighting, and discounting. Under risk, our main result is that probabilistic risk attitude for couples lay within the boundaries of individual attitudes: c...

Different Effects of Cognitive and Non-exercise Physical Leisure Activities on Cognitive Function by Age in Elderly Korean Individuals.

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Jung, Mi Sook; Kim, Hyunli; Lee, Yeji; Kim, Mijung; Chung, Eunyoung

2017-10-01

We aimed to examine the effects of various leisure activities on cognitive impairment in young-old (aged 65-74 years) and old-old (aged ≥ 75 years) adults. In total, 10,279 elderly Korean individuals from the 2014 Korean National Survey on Older Adults' cohort were enrolled in our study. Cognitive impairment was assessed using the standardized score of the Mini-Mental State Examination for Dementia Screening, whereas leisure activities were recorded via self-reporting of the extent and type of leisure activity the subjects involved in over the past year. Multivariate logistic regression was used to assess the effect of leisure activities on cognitive impairment, while controlling for potential covariates. The subjects were more likely to participate in cognitive activities than in non-exercise physical activities. After controlling for selected covariates, involvement in cognitive activities was found to be a significant predictor of cognitive impairment in both the groups, whereas involvement in non-exercise physical activities was not a predictor of cognitive impairment in individuals aged ≥ 75 years. Moreover, depressive symptoms, rural residence, and hearing difficulties were common predictors of cognitive impairment among elderly-Korean-individuals. Leisure activity involvement may help delay cognitive impairment, which is often concomitant with aging. Hence, an early intervention service may significantly benefit both young-old and old-old individuals.

Correlates of individual, and age-related, differences in short-term learning.

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Zhang, Zhiyong; Davis, Hasker P; Salthouse, Timothy A; Tucker-Drob, Elliot M

2007-07-01

Latent growth models were applied to data on multitrial verbal and spatial learning tasks from two independent studies. Although significant individual differences in both initial level of performance and subsequent learning were found in both tasks, age differences were found only in mean initial level, and not in mean learning. In neither task was fluid or crystallized intelligence associated with learning. Although there were moderate correlations among the level parameters across the verbal and spatial tasks, the learning parameters were not significantly correlated with one another across task modalities. These results are inconsistent with the existence of a general (e.g., material-independent) learning ability.

The Effects of Creatine Supplementation on Explosive Performance and Optimal Individual Postactivation Potentiation Time

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Chia-Chi Wang

2016-03-01

Full Text Available Creatine plays an important role in muscle energy metabolism. Postactivation potentiation (PAP is a phenomenon that can acutely increase muscle power, but it is an individualized process that is influenced by muscle fatigue. This study examined the effects of creatine supplementation on explosive performance and the optimal individual PAP time during a set of complex training bouts. Thirty explosive athletes performed tests of back squat for one repetition maximum (1RM strength and complex training bouts for determining the individual optimal timing of PAP, height and peak power of a counter movement jump before and after the supplementation. Subjects were assigned to a creatine or placebo group and then consumed 20 g of creatine or carboxymethyl cellulose per day for six days. After the supplementation, the 1RM strength in the creatine group significantly increased (p < 0.05. The optimal individual PAP time in the creatine group was also significant earlier than the pre-supplementation and post-supplementation of the placebo group (p < 0.05. There was no significant difference in jump performance between the groups. This study demonstrates that creatine supplementation improves maximal muscle strength and the optimal individual PAP time of complex training but has no effect on explosive performance.

Time to Computerized Tomography Scan, Age, and Mortality in Acute Stroke.

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Myint, Phyo Kyaw; Kidd, Andrew C; Kwok, Chun Shing; Musgrave, Stanley D; Redmayne, Oliver; Metcalf, Anthony K; Ngeh, Joseph; Nicolson, Anne; Owusu-Agyei, Peter; Shekhar, Raj; Walsh, Kevin; Day, Diana J; Warburton, Elizabeth A; Bachmann, Max O; Potter, John F

2016-12-01

Time to computerized tomography (CT) is important to institute appropriate and timely hyperacute management in stroke. We aimed to evaluate mortality outcomes in relation to age and time to CT scan. We used routinely collected data in 8 National Health Service trusts in East of England between September 2008 and April 2011. Stroke cases were prospectively identified and confirmed. Odds ratios (ORs) for unadjusted and adjusted models for age categories (24 hours) and in-hospital and early (<7 days) mortality outcomes were calculated. Of the 7693 patients (mean age 76.1 years, 50% male) included, 1151 (16%) died as inpatients and 336 (4%) died within 7 days. Older patients and those admitted from care home had a significantly longer time from admission until CT (P < .001). Patients who had earlier CT scans were admitted to stroke units more frequently (P < .001) but had higher in-patient (P < .001) and 7-day mortality (P < .001). Whereas older age was associated with increased odds of mortality outcomes, longer time to CT was associated with significantly reduced mortality within 7 days (corresponding ORs for the above time periods were 1.00, .61 [95% confidence interval {CI}: .39-.95], .39 [.24-.64], and .16 [.08-.33]) and in-hospital mortality (ORs 1.00, .86 [.64-1.15], .57 [.42-.78] and .71 [.52-.98]). Older age was associated with a significantly longer time to CT. However, using CT scan time as a benchmarking tool in stroke may have inherent limitations and does not appear to be a suitable quality marker. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Individual Case Analysis of Postmortem Interval Time on Brain Tissue Preservation.

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Jeffrey A Blair

Full Text Available At autopsy, the time that has elapsed since the time of death is routinely documented and noted as the postmortem interval (PMI. The PMI of human tissue samples is a parameter often reported in research studies and comparable PMI is preferred when comparing different populations, i.e., disease versus control patients. In theory, a short PMI may alleviate non-experimental protein denaturation, enzyme activity, and other chemical changes such as the pH, which could affect protein and nucleic acid integrity. Previous studies have compared PMI en masse by looking at many different individual cases each with one unique PMI, which may be affected by individual variance. To overcome this obstacle, in this study human hippocampal segments from the same individuals were sampled at different time points after autopsy creating a series of PMIs for each case. Frozen and fixed tissue was then examined by Western blot, RT-PCR, and immunohistochemistry to evaluate the effect of extended PMI on proteins, nucleic acids, and tissue morphology. In our results, immunostaining profiles for most proteins remained unchanged even after PMI of over 50 h, yet by Western blot distinctive degradation patterns were observed in different protein species. Finally, RNA integrity was lower after extended PMI; however, RNA preservation was variable among cases suggesting antemortem factors may play a larger role than PMI in protein and nucleic acid integrity.

The embodied and relational nature of the mind: implications for clinical interventions in aging individuals and populations

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Rejeski WJ

2013-06-01

Full Text Available W Jack Rejeski,1 Lise Gauvin2 1Department of Health and Exercise Science and Department of Geriatric Medicine, Wake Forest University, Winston-Salem, NC, USA; 2Research Center of the University of Montréal Hospital Center, Department of Social and Preventive Medicine, Université de Montréal, Montréal, QC, Canada Abstract: Considerable research over the past decade has garnered support for the notion that the mind is both embodied and relational. Jointly, these terms imply that the brain, physical attributes of the self, and features of our interpersonal relationships and of the environments in which we live jointly regulate energy and information flow; they codetermine how we think, feel, and behave both individually and collectively. In addition to direct experience, evidence supports the view that stimuli embedded within past memories trigger multimodal simulations throughout the body and brain to literally recreate lived experience. In this paper, we review empirical support for the concept of an embodied and relational mind and then reflect on the implications of this perspective for clinical interventions in aging individuals and populations. Data suggest that environmental influences literally “get under the skin” with aging; that musculoskeletal and visceral sensations become more prominent in activities of the mind due to aging biological systems and chronic disease. We argue that conceiving the mind as embodied and relational will grow scientific inquiry in aging, transform how we think about the self-system and well-being, and lead us to rethink health promotion interventions aimed at aging individuals and populations. Keywords: behavior change, gerontology, disablement, well-being, embodiment

Effects of Individual and Group Contingency Interventions on Attendance in Adolescent Part-Time Employees

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Berkovits, Shira Melody; Sturmey, Peter; Alvero, Alicia M.

2012-01-01

This study examined the effects of individual and group monetary contingencies on the attendance of adolescent part-time employees. Attendance increased in both individual and group contingency phases; however staff questionnaire responses indicated a preference for the individual contingencies. Future research should consider staff acceptability…

Standardized Symptom Measurement of Individuals with Early Lyme Disease Over Time.

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Bechtold, Kathleen T; Rebman, Alison W; Crowder, Lauren A; Johnson-Greene, Doug; Aucott, John N

2017-03-01

Understanding the Lyme disease (LD) literature is challenging given the lack of consistent methodology and standardized measurement of symptoms and the impact on functioning. This prospective study incorporates well-validated measures to capture the symptom picture of individuals with early LD from time of diagnosis through 6-months post-treatment. One hundred seven patients with confirmed early LD and 26 healthy controls were evaluated using standardized instruments for pain, fatigue, depressive symptoms, functional impact, and cognitive functioning. Prior to antibiotic treatment, patients experience notable symptoms of fatigue and pain statistically higher than controls. After treatment, there are no group differences, suggesting that symptoms resolve and that there are no residual cognitive impairments at the level of group analysis. However, using subgroup analyses, some individuals experience persistent symptoms that lead to functional decline and these individuals can be identified immediately post-completion of standard antibiotic treatment using well-validated symptom measures. Overall, the findings suggest that ideally-treated early LD patients recover well and experience symptom resolution over time, though a small subgroup continue to suffer with symptoms that lead to functional decline. The authors discuss use of standardized instruments for identification of individuals who warrant further clinical follow-up. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Developing a scale to measure "attachment to the local community" in late middle aged individuals.

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Sakai, Taichi; Omori, Junko; Takahashi, Kazuko; Mitsumori, Yasuko; Kobayashi, Maasa; Ono, Wakanako; Miyazaki, Toshie; Anzai, Hitomi; Saito, Mika

2016-01-01

Objectives This study was conducted to develop a scale for measuring "attachment to the local community" for its use in health services. The scale is also intended to nurture new social relationships in late middle-aged individuals.Methods Thirty items were initially planned to be included in the scale to measure "attachment to the local community", according to a previous study that identified the concept. The study subjects were late middle-aged residents of City B in Prefecture A, located in Tokyo suburbs. From the basic resident register data, 1,000 individuals (local residents in the 50-69 year age group) were selected by a multi-stage random sampling technique, on the basis of their residential area, age, and sex (while maintaining the male to female ratio). An unsigned self-administered questionnaire was distributed to the subjects, and the responses were collected by postal mail. The collected data was analyzed using psychometric study of scale.Results Valid responses were obtained from 583 subjects, and the response rate was 58.3%. In an item analysis, none of the items were rejected. In a subsequent factor analysis, 7 items were eliminated. These items included 2 items with a factor loading of attachment to the local community" was 0.95, demonstrating internal consistency. We then examined the correlation with an existing scale to measure social support; the results revealed a statistically significant correlation and confirmed criterion-related validity (Pattachment to the local community."

Discrete-time moment closure models for epidemic spreading in populations of interacting individuals.

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Frasca, Mattia; Sharkey, Kieran J

2016-06-21

Understanding the dynamics of spread of infectious diseases between individuals is essential for forecasting the evolution of an epidemic outbreak or for defining intervention policies. The problem is addressed by many approaches including stochastic and deterministic models formulated at diverse scales (individuals, populations) and different levels of detail. Here we consider discrete-time SIR (susceptible-infectious-removed) dynamics propagated on contact networks. We derive a novel set of 'discrete-time moment equations' for the probability of the system states at the level of individual nodes and pairs of nodes. These equations form a set which we close by introducing appropriate approximations of the joint probabilities appearing in them. For the example case of SIR processes, we formulate two types of model, one assuming statistical independence at the level of individuals and one at the level of pairs. From the pair-based model we then derive a model at the level of the population which captures the behavior of epidemics on homogeneous random networks. With respect to their continuous-time counterparts, the models include a larger number of possible transitions from one state to another and joint probabilities with a larger number of individuals. The approach is validated through numerical simulation over different network topologies. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Balance training reduces falls risk in older individuals with type 2 diabetes.

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Morrison, Steven; Colberg, Sheri R; Mariano, Mira; Parson, Henri K; Vinik, Arthur I

2010-04-01

This study assessed the effects of balance/strength training on falls risk and posture in older individuals with type 2 diabetes. Sixteen individuals with type 2 diabetes and 21 age-matched control subjects (aged 50-75 years) participated. Postural stability and falls risk was assessed before and after a 6-week exercise program. Diabetic individuals had significantly higher falls risk score compared with control subjects. The diabetic group also exhibited evidence of mild-to-moderate neuropathy, slower reaction times, and increased postural sway. Following exercise, the diabetic group showed significant improvements in leg strength, faster reaction times, decreased sway, and, consequently, reduced falls risk. Older individuals with diabetes had impaired balance, slower reactions, and consequently a higher falls risk than age-matched control subjects. However, all these variables improved after resistance/balance training. Together these results demonstrate that structured exercise has wide-spread positive effects on physiological function for older individuals with type 2 diabetes.

Relationship between Amount of Exited Blood During Wet-cupping with Patient’s Individual Conditions and the Time of Doing it

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Ghazanfari M

2017-12-01

Full Text Available Aims Wet-cupping as a therapeutic method has been recommended to be done on certain days based on authentic sources of traditional medicine in Iran. The purpose of this study was to determine the relationship between amount of exited blood during wet-cupping with patient’s individual conditions and the time it was performed. Instruments & Methods In this descriptive cross-sectional study, 391 men who were referred to a cupping center in Saveh city in the spring of 2016, were selected by simple sampling and wet-cupping in the position between the two scapula was performed. The research instrument was a questionnaire including demographic characteristics, date of reference (day, month and year, age, height, weight and amount of exited blood during the wet-cupping in gram. Data were analyzed by SPSS 16 software and using chi-square test, paired t test and one-way analysis of variance. Findings The means of age, weight and body mass index were significantly related to the mean of amount of exited blood during wet-cupping (p0.05, but the amount of exited blood was higher in people with previous history of wet-cupping than those without previous history (p<0.001. Also, in people with hypertension, the amount of exited blood was higher than other treatment groups (p<0.05. Conclusion Individual characteristics such as age, weight, body mass index, cause of referral and previous history of wet-cupping affect the amount of exited blood during wet-cupping, but the time of wet-cupping (day and month does not affect the amount of exited blood.

Reliability of Interaural Time Difference-Based Localization Training in Elderly Individuals with Speech-in-Noise Perception Disorder

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Maryam Delphi

2017-09-01

Full Text Available Background: Previous studies have shown that interaural-time-difference (ITD training can improve localization ability. Surprisingly little is, however, known about localization training vis-à-vis speech perception in noise based on interaural time difference in the envelope (ITD ENV. We sought to investigate the reliability of an ITD ENV-based training program in speech-in-noise perception among elderly individuals with normal hearing and speech-in-noise disorder. Methods: The present interventional study was performed during 2016. Sixteen elderly men between 55 and 65 years of age with the clinical diagnosis of normal hearing up to 2000 Hz and speech-in-noise perception disorder participated in this study. The training localization program was based on changes in ITD ENV. In order to evaluate the reliability of the training program, we performed speech-in-noise tests before the training program, immediately afterward, and then at 2 months’ follow-up. The reliability of the training program was analyzed using the Friedman test and the SPSS software. Results: Significant statistical differences were shown in the mean scores of speech-in-noise perception between the 3 time points (P=0.001. The results also indicated no difference in the mean scores of speech-in-noise perception between the 2 time points of immediately after the training program and 2 months’ follow-up (P=0.212. Conclusion: The present study showed the reliability of an ITD ENV-based localization training in elderly individuals with speech-in-noise perception disorder.

Bedtime and evening light exposure influence circadian timing in preschool-age children: A field study

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Lameese D. Akacem

2016-11-01

Full Text Available Light exposure and sleep timing are two factors that influence inter-individual variability in the timing of the human circadian clock. The aim of this study was to quantify the degree to which evening light exposure predicts variance in circadian timing over and above bedtime alone in preschool children. Participants were 21 children ages 4.5–5.0 years (4.7±0.2 years; 9 females. Children followed their typical sleep schedules for 4 days during which time they wore a wrist actigraph to assess sleep timing and a pendant light meter to measure minute-by-minute illuminance levels in lux. On the 5th day, children participated in an in-home dim-light melatonin onset (DLMO assessment. Light exposure in the 2 h before bedtime was averaged and aggregated across the 4 nights preceding the DLMO assessment. Mean DLMO and bedtime were 19:22±01:04 and 20:07±00:46, respectively. Average evening light exposure was 710.1±1418.2 lux. Children with later bedtimes (lights-off time had more delayed melatonin onset times (r=0.61, p=0.002. Evening light exposure was not independently associated with DLMO (r=0.32, p=0.08; however, a partial correlation between evening light exposure and DLMO when controlling for bedtime yielded a positive correlation (r=0.46, p=0.02. Bedtime explained 37.3% of the variance in the timing of DLMO, and evening light exposure accounted for an additional 13.3% of the variance. These findings represent an important step in understanding factors that influence circadian phase in preschool-age children and have implications for understanding a modifiable pathway that may underlie late sleep timing and the development of evening settling problems in early childhood.

'Inconvenient biology:' advantages and disadvantages of first-time parenting after age 40 using in vitro fertilization.

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Mac Dougall, K; Beyene, Y; Nachtigall, R D

2012-04-01

As ages at first birth have steadily risen in the industrial west over the last several decades, the phenomenon of 'delayed childbearing' has come under research scrutiny by demographers, medical specialists and social scientists. In this study, we specifically explore the perceived advantages and disadvantages of postponed conception as well as participants' retrospective opinions on the 'optimal age' for parenting. To this end, we examined a cohort purposely chosen to epitomize delayed childbearing, i.e. men and women who used IVF to conceive at the very end of their reproductive capability. In-depth qualitative interviews were conducted between 2009 and 2011 with 46 couples and 15 individual self-selected US women and men who had used IVF to conceive their first child when the woman was aged 40 or older at the time of delivery. Although the demographics of this cohort were consistent with others who use IVF in the USA, their median income was 3-4 times higher than that of the average US family, which may bias their largely positive parenting experiences. Most women and men believed that childbearing later in life resulted in advantages for themselves and their families. These included having established careers with financial security and career-time flexibility, enhanced emotional preparedness, committed co-parenting relationships and a positive overall family experience. The main disadvantage was the unexpected difficulty in conceiving that culminated in the use of IVF and resulted in a smaller family than desired, although many expressed feeling 'lucky' to have children at all. Other disadvantages were lack of energy for parenting, less available lifetime to spend with children and anticipated stigma as older parents. These disadvantages appear to have influenced conception and parenting experiences so that in hindsight the majority of participants identified the optimal age for first-time parenting as 5-10 years earlier than they had conceived. This age

Influence of Biomedical Factors on the Five Viscera Score (FVS on Middle-Aged and Elderly Individuals: Application of Structural Equation Modeling

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Taro Tomura

2015-01-01

Full Text Available The five viscera score (FVS is a diagnostic scale for traditional Chinese medicine (TCM. The purposes of current study are to elucidate the characteristics of FVS obtained from middle-aged to elderly individuals and to investigate the validity of FVS using biological medical data of middle-aged and elderly individuals. Structural equation modeling (SEM was used to conduct assessments between FVS and medical data. Eighty men and 99 women participated in this study, whose mean ages (SD were 58 ± 7 years in both genders showing no significant difference. FVS of women was significantly higher than that of men in the spleen of the 50s (P=0.019 and liver of the 60s age group (P=0.030. By SEM, the following biomedical factors were found to influence viscera: gender, diastolic blood pressure, and HDL-C for the liver; GLU, GOT, and γ-GTP for the spleen; age, BMI, and HCRP for the lungs; and HbA1c and creatinine clearance for the kidneys. These results provide objective evidence that FVS can be used for TCM diagnosis in middle-aged and elderly individuals.

Individual- and area-level effects on mortality risk in Germany, both East and West, among male Germans aged 65+

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Kibele, E.

2014-01-01

Objectives This study investigates whether mortality inequalities based on individual- and area-level deprivation exist at older ages in Germany, and whether there are differences between eastern and western Germany. Methods Data on population and death counts according to the individual-level

Individual differences in motor timing and its relation to cognitive and fine motor skills.

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Håvard Lorås

Full Text Available The present study investigated the relationship between individual differences in timing movements at the level of milliseconds and performance on selected cognitive and fine motor skills. For this purpose, young adult participants (N = 100 performed a repetitive movement task paced by an auditory metronome at different rates. Psychometric measures included the digit-span and symbol search subtasks from the Wechsler battery as well as the Raven SPM. Fine motor skills were assessed with the Purdue Pegboard test. Motor timing performance was significantly related (mean r = .3 to cognitive measures, and explained both unique and shared variance with information-processing speed of Raven's scores. No significant relations were found between motor timing measures and fine motor skills. These results show that individual differences in cognitive and motor timing performance is to some extent dependent upon shared processing not associated with individual differences in manual dexterity.

Age related differences in individual quality of life domains in youth with type 1 diabetes

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Lett Syretta

2004-09-01

Full Text Available Abstract Background Investigating individual, as opposed to predetermined, quality of life domains may yield important information about quality of life. This study investigated the individual quality of life domains nominated by youth with type 1 diabetes. Methods Eighty young people attending a diabetes summer camp completed the Schedule for the Evaluation of Individual Quality of Life-Direct Weighting interview, which allows respondents to nominate and evaluate their own quality of life domains. Results The most frequently nominated life domains were 'family', 'friends', 'diabetes', 'school', and 'health' respectively; ranked in terms of importance, domains were 'religion', 'family', 'diabetes', 'health', and 'the golden rule'; ranked in order of satisfaction, domains were 'camp', 'religion', 'pets', and 'family' and 'a special person' were tied for fifth. Respondent age was significantly positively associated with the importance of 'friends', and a significantly negatively associated with the importance of 'family'. Nearly all respondents nominated a quality of life domain relating to physical status, however, the specific physical status domain and the rationale for its nomination varied. Some respondents nominated 'diabetes' as a domain and emphasized diabetes 'self-care behaviors' in order to avoid negative health consequences such as hospitalization. Other respondents nominated 'health' and focused more generally on 'living well with diabetes'. In an ANOVA with physical status domain as the independent variable and age as the dependent variable, participants who nominated 'diabetes' were younger (M = 12.9 years than those who nominated 'health' (M = 15.9 years. In a second ANOVA, with rationale for nomination the physical status domain as the independent variable, and age as the dependent variable, those who emphasized 'self care behaviors' were younger (M = 11.8 years than those who emphasized 'living well with diabetes' (M = 14.6 years

Middle Pleistocene lower back and pelvis from an aged human individual from the Sima de los Huesos site, Spain.

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Bonmatí, Alejandro; Gómez-Olivencia, Asier; Arsuaga, Juan-Luis; Carretero, José Miguel; Gracia, Ana; Martínez, Ignacio; Lorenzo, Carlos; Bérmudez de Castro, José María; Carbonell, Eudald

2010-10-26

We report a nearly complete lumbar spine from the Middle Pleistocene site of the Sima de los Huesos (SH) that is assigned to the previously published SH male Pelvis 1 [Arsuaga JL, et al. (1999). Nature 399: 255-258]. The "SH Pelvis 1 individual" is a unique nearly complete lumbo-pelvic complex from the human Middle Pleistocene fossil record, and offers a rare glimpse into the anatomy and past lifeways of Homo heidelbergensis. A revised reconstruction of Pelvis 1, together with the current fossil evidence, confirms our previous hypothesis that the morphology of this pelvis represents the primitive pattern within the genus Homo. Here we argue that this primitive pattern is also characterized by sexual dimorphism in the pelvic canal shape, implying complicated deliveries. In addition, this individual shows signs of lumbar kyphotic deformity, spondylolisthesis, and Baastrup disease. This suite of lesions would have postural consequences and was most likely painful. As a result, the individual's daily physical activities would have been restricted to some extent. Reexamination of the age-at-death agrees with this individual being over 45 y old, relying on the modern human pattern of changes of the articular surfaces of the os coxae. The presence of degenerative pathological lesions and the advanced age-at-death of this individual make it the most ancient postcranial evidence of an aged individual in the human fossil record. Additional nonpathological SH lumbo-pelvic remains are consistent with previous hypotheses, suggesting a less-pronounced sagittal spinal curvature in Neandertals compared with Homo sapiens.

Age Group Comparisons of TENS Response Among Individuals With Chronic Axial Low Back Pain.

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Simon, Corey B; Riley, Joseph L; Fillingim, Roger B; Bishop, Mark D; George, Steven Z

2015-12-01

Chronic low back pain (CLBP) is a highly prevalent and disabling musculoskeletal pain condition among older adults. Transcutaneous electrical nerve stimulation (TENS) is commonly used to treat CLBP, however response to TENS in older adults compared with younger adults is untested. In a dose-response study stratified by age, 60 participants with axial CLBP (20 young, 20 middle-aged, 20 older) received four 20-minute sessions of high-frequency high-intensity TENS over a 2- to 3-week period in a laboratory-controlled setting. Experimental measures of pain sensitivity (mechanical pressure pain detection threshold) and central pain excitability (phasic heat temporal summation and heat aftersensations) were assessed before and after TENS. Episodic or immediate axial CLBP relief was assessed after TENS via measures of resting pain, movement-evoked-pain, and self-reported disability. Cumulative or prolonged axial CLBP relief was assessed by comparing daily pain reports across sessions. Independent of age, individuals experienced episodic increase in the pressure pain detection threshold and reduction in aftersensation after TENS application. Similarly, all groups, on average, experienced episodic axial CLBP relief via improved resting pain, movement-evoked pain, and disability report. Under this design, no cumulative effect was observed as daily pain did not improve for any age group across the 4 sessions. However, older adults received higher TENS amplitude across all sessions to achieve TENS responses similar to those in younger adults. These findings suggest that older adults experience similar episodic axial CLBP relief to that of younger individuals after high-frequency, high-intensity TENS when higher dose parameters are used. This study examined age group differences in experimental and axial CLBP response to TENS, delivered under the current recommended parameters of strong, but tolerable amplitude. Older adults had comparable TENS response although at higher TENS

42 CFR 436.222 - Individuals under age 21 who meet the income and resource requirements of AFDC.

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2010-10-01

... GUAM, PUERTO RICO, AND THE VIRGIN ISLANDS Options for Coverage as Categorically Needy Options for... nursing facility services are provided under the plan to individuals within the age group selected under...

Effecting aging time of epoxy molding compound to molding process for integrated circuit packaging

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Tachapitunsuk, Jirayu; Ugsornrat, Kessararat; Srisuwitthanon, Warayoot; Thonglor, Panakamon

2017-09-01

This research studied about effecting aging time of epoxy molding compound (EMC) that effect to reliability performance of integrated circuit (IC) package in molding process. Molding process is so important of IC packaging process for protecting IC chip (or die) from temperature and humidity environment using encapsulated EMC. For general molding process, EMC are stored in the frozen at 5°C and left at room temperature at 25 °C for aging time on self before molding of die onto lead frame is 24 hours. The aging time effect to reliability performance of IC package due to different temperature and humidity inside the package. In experiment, aging time of EMC were varied from 0 to 24 hours for molding process of SOIC-8L packages. For analysis, these packages were tested by x-ray and scanning acoustic microscope to analyze properties of EMC with an aging time and also analyzed delamination, internal void, and wire sweep inside the packages with different aging time. The results revealed that different aging time of EMC effect to properties and reliability performance of molding process.

Individual Mortality and Macro-Economic Conditions from Birth to Death

NARCIS (Netherlands)

Lindeboom, Maarten; Portrait, France; Berg, van den G.J.

2003-01-01

This paper analyzes the effects of macro-economic conditions throughout life on the individual mortality rate. We estimate flexible duration models where the individual's mortality rate depends on current conditions, conditions earlier in life (notably during childhood), calendar time, age,

Real-time individualized training vectors for experiential learning.

Energy Technology Data Exchange (ETDEWEB)

Willis, Matt; Tucker, Eilish Marie; Raybourn, Elaine Marie; Glickman, Matthew R.; Fabian, Nathan

2011-01-01

Military training utilizing serious games or virtual worlds potentially generate data that can be mined to better understand how trainees learn in experiential exercises. Few data mining approaches for deployed military training games exist. Opportunities exist to collect and analyze these data, as well as to construct a full-history learner model. Outcomes discussed in the present document include results from a quasi-experimental research study on military game-based experiential learning, the deployment of an online game for training evidence collection, and results from a proof-of-concept pilot study on the development of individualized training vectors. This Lab Directed Research & Development (LDRD) project leveraged products within projects, such as Titan (Network Grand Challenge), Real-Time Feedback and Evaluation System, (America's Army Adaptive Thinking and Leadership, DARWARS Ambush! NK), and Dynamic Bayesian Networks to investigate whether machine learning capabilities could perform real-time, in-game similarity vectors of learner performance, toward adaptation of content delivery, and quantitative measurement of experiential learning.

Relative Age Effect and Academic Timing in American Junior College Baseball.

Science.gov (United States)

Beals, Thomas C; Furtado, Ovande; Fontana, Fabio E

2018-02-01

Previous research has shown that older athletes within age groupings are often perceived to be more talented simply due to advanced maturity, leading to biased selection in higher levels of sports competition, now commonly termed relative age effect (RAE). This study's goals were to determine whether (a) RAE influenced the selection of junior college baseball participants and (b) academic timing ( Glamser & Marciani, 1992 ), in which academic status determines age groupings more than strict age guidelines for college sports, influenced the formation of RAE. Participants were 150 junior college baseball players. Our results showed that RAE was only a significant factor, comparing the birth distribution of participants born before and after the midpoint of the participation year, when academic timing was also a factor in determining age groupings. In addition, the birth rate distribution, though not significantly different than expected, was greater only when those participants born during the expected participation year were included. The results of this study indicate that RAE could bear more influence among American student-athletes than was previously reported in that RAE in conjunction with academic timing does influence the selection of collegiate athletes.

The Common HNF1A Variant I27L is a Modifier of Age at Diabetes Diagnosis in HNF1A-MODY Individuals.

Science.gov (United States)

Locke, Jonathan M; Saint-Martin, Cécile; Laver, Thomas W; Patel, Kashyap A; Wood, Andrew R; Sharp, Seth A; Ellard, Sian; Bellanné-Chantelot, Christine; Hattersley, Andrew T; Harries, Lorna W; Weedon, Michael N

2018-06-12

There is wide variation in the age at diagnosis of diabetes in individuals with Maturity-Onset Diabetes of the Young (MODY) due to a mutation in the HNF1A gene. We hypothesised that common variants at the HNF1A locus (rs1169288, I27L; rs1800574, A98V), which are associated with type 2 diabetes susceptibility, may modify age at diabetes diagnosis in HNF1A-MODY individuals. Meta-analysis of two independent cohorts, comprising 781 HNF1A-MODY individuals, found no significant associations between genotype and age at diagnosis. However after stratifying according to type of mutation (protein-truncating variant (PTV) or missense), we found each 27L allele to be associated with a 1.6 year decrease (95% CI -2.6, -0.7) in age at diagnosis, specifically in the subset (n=444) of HNF1A-MODY individuals with a PTV. The effect size was similar and significant across the two independent cohorts of HNF1A-MODY individuals. We report a robust genetic modifier of HNF1A-MODY age at diagnosis that further illustrates the strong effect of genetic variation within HNF1A upon diabetes phenotype. © 2018 by the American Diabetes Association.

Residual Motion and Duty Time in Respiratory Gating Radiotherapy Using Individualized or Population-Based Windows

International Nuclear Information System (INIS)

Fuji, Hiroshi; Asada, Yoshihiro; Numano, Masumi; Yamashita, Haruo; Nishimura, Tetsuo; Hashimoto, Takayuki; Harada, Hideyuki; Asakura, Hirofumi; Murayama, Shigeyuki

2009-01-01

Purpose: The efficiency and precision of respiratory gated radiation therapy for tumors is affected by variations in respiration-induced tumor motion. We evaluated the use of individualized and population-based parameters for such treatment. Methods and Materials: External respiratory signal records and images of respiration-induced tumor motion were obtained from 42 patients undergoing respiratory gated radiation therapy for liver tumors. Gating window widths were calculated for each patient, with 2, 4, and 10 mm of residual motion, and the mean was defined as the population-based window width. Residual motions based on population-based and predefined window widths were compared. Duty times based on whole treatment sessions, at various window levels, were calculated. The window level giving the longest duty time was defined as the individualized most efficient level (MEL). MELs were also calculated based on the first 10 breathing cycles. The duty times for population-based MELs (defined as mean MELs) and individualized MELs were compared. Results: Tracks of respiration-induced tumor motion ranged from 3 to 50 mm. Half of the patients had larger actual residual motions than the assigned residual motions. Duty times were greater when based on individualized, rather than population-based, window widths. The MELs established during whole treatment sessions for 2 mm and 4 mm of residual motion gave significantly increased duty times, whereas those calculated using the first 10 breathing cycles showed only marginal increases. Conclusions: Using individualized window widths and levels provided more precise and efficient respiratory gated radiation therapy. However, methods for predicting individualized window levels before treatment remain to be explored.

Influence of age and gender in response to {gamma}-radiation in Portuguese individuals using chromosomal aberration assay - Preliminary findings

Energy Technology Data Exchange (ETDEWEB)

Martins, V.; Antunes, A.C. [Instituto Tecnologico e Nuclear, Unidade de Proteccao e Seguranca Radiologica, Dosimetry and Radiobiology Group, E.N. 10, Apartado 21, 2686-953 Sacavem (Portugal); Cardoso, J.; Santos, L. [Instituto Tecnologico e Nuclear, Unidade de Proteccao e Seguranca Radiologica, Metrology Laboratory of Ionizing Radiation, E.N. 10, Apartado 21, 2686-953 Sacavem (Portugal); Gil, O. Monteiro, E-mail: octavia.gil@itn.pt [Instituto Tecnologico e Nuclear, Unidade de Proteccao e Seguranca Radiologica, Dosimetry and Radiobiology Group, E.N. 10, Apartado 21, 2686-953 Sacavem (Portugal)

2011-09-15

Cytogenetic indicators are widely used in radiobiology to evaluate effects of ionizing radiation since dicentric chromosomes (Dic) are almost exclusively induced by ionizing radiation, and spontaneous frequency of Dic is very low in the healthy general population (about one Dic per 1000 cells). A particular interest of biodosimetry has been not only to obtain absorbed dose estimates using adequate calibration curves, under the assumption that all individuals respond equally to radiation-induced chromosome aberrations, but also to find a way to demonstrate inter-individual radiosensitivity and a possible correlation with age and gender. Thus, the objective of this preliminary work was the evaluation of the influence of age and gender on the outcome of cytogenetic biomarkers after {gamma}-irradiation. Samples of peripheral blood lymphocytes from six healthy, non-smoker, donors from both genders (three men and three women), in the range of 20 to 49 years, were irradiated with doses from 0 Gy to 3 Gy air kerma, using a {sup 60}Co gamma rays source with a dose rate from 170-180 mGy/min. A clear dose-dependent increase in terms of aberrant cells excluding gaps (ACEG) and Dic was observed for all donors. Our preliminary results suggest, in the higher dose level evaluated (3 Gy), a larger intervariability among individuals for Dic, with females apparently more sensitive than males (P<0.05). Considering the different age groups, male donors showed a decrease, with age, for Dic and ACEG at the higher dose and also, for the background level, in case of ACEG. Future work will consider the study of more individuals, from both genders and different ages, in order to verify if this tendency persists and to enable the implementation of a dose-response calibration curve at Instituto Tecnologico e Nuclear for the Portuguese population, to quantify the biological dose in case of a radiological accident or emergency.

Influence of age and gender in response to γ-radiation in Portuguese individuals using chromosomal aberration assay - Preliminary findings

International Nuclear Information System (INIS)

Martins, V.; Antunes, A.C.; Cardoso, J.; Santos, L.; Gil, O. Monteiro

2011-01-01

Cytogenetic indicators are widely used in radiobiology to evaluate effects of ionizing radiation since dicentric chromosomes (Dic) are almost exclusively induced by ionizing radiation, and spontaneous frequency of Dic is very low in the healthy general population (about one Dic per 1000 cells). A particular interest of biodosimetry has been not only to obtain absorbed dose estimates using adequate calibration curves, under the assumption that all individuals respond equally to radiation-induced chromosome aberrations, but also to find a way to demonstrate inter-individual radiosensitivity and a possible correlation with age and gender. Thus, the objective of this preliminary work was the evaluation of the influence of age and gender on the outcome of cytogenetic biomarkers after γ-irradiation. Samples of peripheral blood lymphocytes from six healthy, non-smoker, donors from both genders (three men and three women), in the range of 20 to 49 years, were irradiated with doses from 0 Gy to 3 Gy air kerma, using a 60 Co gamma rays source with a dose rate from 170-180 mGy/min. A clear dose-dependent increase in terms of aberrant cells excluding gaps (ACEG) and Dic was observed for all donors. Our preliminary results suggest, in the higher dose level evaluated (3 Gy), a larger intervariability among individuals for Dic, with females apparently more sensitive than males (P<0.05). Considering the different age groups, male donors showed a decrease, with age, for Dic and ACEG at the higher dose and also, for the background level, in case of ACEG. Future work will consider the study of more individuals, from both genders and different ages, in order to verify if this tendency persists and to enable the implementation of a dose-response calibration curve at Instituto Tecnologico e Nuclear for the Portuguese population, to quantify the biological dose in case of a radiological accident or emergency.

Age and Time Population Differences: Young Adults, Gen Xers, and Millennials

Science.gov (United States)

Menard, Lauren A.

2013-01-01

Age and Time disparities in young adult research populations are common because young adults are defined by varying age spans; members of Generation X and Millennial generations may both be considered young adults; study years vary, affecting populations; and qualitative methods with limited age/year samples are frequently utilized. The current…

Standardization of a rearing procedure of Tetranychus urticae Koch (Acari: Tetranychidae) on bean (Phaseolus vulgaris): plant age and harvest time

International Nuclear Information System (INIS)

Bustos, Alexander; Cantor, Fernando; Cure, Jose R; Rodriguez, Daniel

2009-01-01

A rearing technique was standardized to produce Tetranychus urticae Koch on Phaseolus vulgaris (ICA Cerinza variety) as a prey of the predatory mite Phytoseiulus persimilis Athias-Henriot. Two assays were conducted to assess the following variables: the most suitable plant age for mite infestation, and the best time to harvest the mites and re infest the plants. In the first experiment, four, five, six, and seven-week-old plants of P. vulgaris were infested with six T. urticae per foliole. The lower plant stratum exhibited the largest number of mites regardless of plant age. However, four-week old plants had the larger average number of individuals. In the second experiment four-week-old plants were infested with 0.5 female mite/cm 2 of leaf. The number of individuals per instar of T. urticae was recorded weekly. The highest mite production occurred between four and five weeks after infestation, indicating this to be the most suitable for mite harvesting and for plant reinfestation. (author)

Perceptions of Life Changes: An Alternate Measure of Aging through Time.

Science.gov (United States)

Suggs, Patricia K.; Kivett, Vira R.

Retrospective strategies measuring perceived life changes over time can further the advancement of life span developmental research. Researchers have neglected the individual's perception of his/her life changes over time. This study attempts to determine discriminators of change over time as operationalized by perceptions of change. Subjects…

20 CFR 416.415 - Amount of benefits; eligible individual is disabled child under age 18.

Science.gov (United States)

2010-04-01

... and your benefit rate will be $30 a month. (b) If you are a disabled child under age 18 and do not... payable if you received benefits as a child under § 416.1165(i), your benefit will be the amount payable... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Amount of benefits; eligible individual is...

Preference and Popularity of Individual Sport Activities among Older School - Age and Teenage Children in Kolín

OpenAIRE

Keltner, Michal

2015-01-01

This diploma thesis deals with the topic called "Preferences and Popularity of Individual Sports Branches by Children of Older School and Junior Age in Kolín". In the theoretic part I focused on definition of the main terms which occur in the name of the thesis as preferences, popularity, sports branch, children of older school age and children of junior age. Discovered data were processed on the basis of quantitative method via questionnaire survey and the evaluation was carried out via spre...

Dental age estimation in Japanese individuals combining permanent teeth and third molars.

Science.gov (United States)

Ramanan, Namratha; Thevissen, Patrick; Fleuws, Steffen; Willems, G

2012-12-01

The study aim was, firstly, to verify the Willems et al. model on a Japanese reference sample. Secondly to develop a Japanese reference model based on the Willems et al. method and to verify it. Thirdly to analyze the age prediction performance adding tooth development information of third molars to permanent teeth. Retrospectively 1877 panoramic radiographs were selected in the age range between 1 and 23 years (1248 children, 629 sub-adults). Dental development was registered applying Demirjian 's stages of the mandibular left permanent teeth in children and Köhler stages on the third molars. The children's data were, firstly, used to validate the Willems et al. model (developed a Belgian reference sample), secondly, split ino a training and a test sample. On the training sample a Japanese reference model was developed based on the Willems method. The developed model and the Willems et al; model were verified on the test sample. Regression analysis was used to detect the age prediction performance adding third molar scores to permanent tooth scores. The validated Willems et al. model provided a mean absolute error of 0.85 and 0.75 years in females and males, respectively. The mean absolute error in the verified Willems et al. and the developed Japanese reference model was 0.85, 0.77 and 0.79, 0.75 years in females and males, respectively. On average a negligible change in root mean square error values was detected adding third molar scores to permanent teeth scores. The Belgian sample could be used as a reference model to estimate the age of the Japanese individuals. Combining information from the third molars and permanent teeth was not providing clinically significant improvement of age predictions based on permanent teeth information alone.

Age at Menarche and Time Spent in Education: A Mendelian Randomization Study.

Science.gov (United States)

Gill, D; Del Greco M, F; Rawson, T M; Sivakumaran, P; Brown, A; Sheehan, N A; Minelli, C

2017-09-01

Menarche signifies the primary event in female puberty and is associated with changes in self-identity. It is not clear whether earlier puberty causes girls to spend less time in education. Observational studies on this topic are likely to be affected by confounding environmental factors. The Mendelian randomization (MR) approach addresses these issues by using genetic variants (such as single nucleotide polymorphisms, SNPs) as proxies for the risk factor of interest. We use this technique to explore whether there is a causal effect of age at menarche on time spent in education. Instruments and SNP-age at menarche estimates are identified from a Genome Wide Association Study (GWAS) meta-analysis of 182,416 women of European descent. The effects of instruments on time spent in education are estimated using a GWAS meta-analysis of 118,443 women performed by the Social Science Genetic Association Consortium (SSGAC). In our main analysis, we demonstrate a small but statistically significant causal effect of age at menarche on time spent in education: a 1 year increase in age at menarche is associated with 0.14 years (53 days) increase in time spent in education (95% CI 0.10-0.21 years, p = 3.5 × 10 -8 ). The causal effect is confirmed in sensitivity analyses. In identifying this positive causal effect of age at menarche on time spent in education, we offer further insight into the social effects of puberty in girls.

Time Estimation Deficits in Childhood Mathematics Difficulties

Science.gov (United States)

Hurks, Petra P. M.; van Loosbroek, Erik

2014-01-01

Time perception has not been comprehensively examined in mathematics difficulties (MD). Therefore, verbal time estimation, production, and reproduction were tested in 13 individuals with MD and 16 healthy controls, matched for age, sex, and intellectual skills. Individuals with MD performed comparably to controls in time reproduction, but showed a…

Physical Activity Level and Physical Functionality in Nonagenarians Compared to Individuals Aged 60–74 Years

Science.gov (United States)

Frisard, Madlyn I.; Fabre, Jennifer M.; Russell, Ryan D.; King, Christina M.; DeLany, James P.; Wood, Robert H.; Ravussin, Eric

2009-01-01

Background Functional dependence and the risks of disability increase with age. The loss of independence is thought to be partially due to a decrease in physical activity. However, in populations, accurate measurement of physical activity is challenging and may not provide information on functional impairment. Methods This study therefore assessed physical functionality and physical activity level in a group of nonagenarians (11 men/11 women; 93 ± 1 years, 66.6 ± 2.4 kg, body mass index [BMI] = 24 ± 1 kg/m2) and a group of participants aged 60–74 years (17 men/15 women; 70 ± 1 years, 83.3 ± 3.0 kg, BMI = 29 ± 1 kg/m2) from the Louisiana Healthy Aging Study. Physical activity level was calculated from total energy expenditure (TEE) and resting metabolic rate (RMR). Physical functionality was assessed using the Reduced Continuous Scale Physical Functional Performance Test (CS-PFP10). Results Nonagenarians had lower absolute ( p < .001) and adjusted ( p < .007) TEE compared to participants aged 60–74 years which was attributed to a reduction in both RMR and physical activity level. Nonagenarians also had reduced functional performance ( p < .001) which was correlated with activity level (r = 0.68, p < .001). Conclusions When compared to individuals aged 60–74 years, 73% of the reduction in TEE in nonagenarians can be attributed to a reduction in physical activity level, the remaining being accounted for by a reduction in RMR. The reduced physical activity in nonagenarians is associated with less physical functionality. This study provides the first objective comparison of physical functionality and actual levels of physical activity in older individuals. PMID:17634327

Interaction of hypertension and age in visual selective attention performance.

Science.gov (United States)

Madden, D J; Blumenthal, J A

1998-01-01

Previous research suggests that some aspects of cognitive performance decline as a joint function of age and hypertension. In this experiment, 51 unmedicated individuals with mild essential hypertension and 48 normotensive individuals, 18-78 years of age, performed a visual search task. The estimated time required to identify a display character and shift attention between display positions increased with age. This attention shift time did not differ significantly between hypertensive and normotensive participants, but regression analyses indicated some mediation of the age effect by blood pressure. For individuals less than 60 years of age, the error rate was greater for hypertensive than for normotensive participants. Although the present design could detect effects of only moderate to large size, the results suggest that effects of hypertension may be more evident in a relatively general measure of performance (mean error rate) than in the speed of shifting visual attention.

Age-dependent terminal declines in reproductive output in a wild bird.

Directory of Open Access Journals (Sweden)

Martijn Hammers

Full Text Available In many iteroparous species individual fitness components, such as reproductive output, first increase with age and then decline during late-life. However, individuals differ greatly in reproductive lifespan, but reproductive declines may only occur in the period just before their death as a result of an age-independent decline in physiological condition. To fully understand reproductive senescence it is important to investigate to what extent declines in late-life reproduction can be explained by age, time until death, or both. However, the study of late-life fitness performance in natural populations is challenging as the exact birth and death dates of individuals are often not known, and most individuals succumb to extrinsic mortality before reaching old age. Here, we used an exceptional long-term longitudinal dataset of individuals from a natural, closed, and predator-free population of the Seychelles warbler (Acrocephalus sechellensis to investigate reproductive output, both in relation to age and to the time until the death of an individual (reverse-age approach. We observed an initial age-dependent increase in reproductive output that was followed by a decline in old age. However, we found no significant decline in reproductive output in the years directly preceding death. Although post-peak reproductive output declined with age, this pattern differed between terminal and non-terminal reproductive attempts, and the age-dependence of the terminal breeding attempt explained much of the variation in age-specific reproductive output. In fact, terminal declines in reproductive output were steeper in very old individuals. These results indicate that not only age-dependent, but also age-independent factors, such as physiological condition, need to be considered to understand reproductive senescence in wild-living animals.

Measuring Biological Age via Metabonomics: The Metabolic Age Score.

Science.gov (United States)

Hertel, Johannes; Friedrich, Nele; Wittfeld, Katharina; Pietzner, Maik; Budde, Kathrin; Van der Auwera, Sandra; Lohmann, Tobias; Teumer, Alexander; Völzke, Henry; Nauck, Matthias; Grabe, Hans Jörgen

2016-02-05

Chronological age is one of the most important risk factors for adverse clinical outcome. Still, two individuals at the same chronological age could have different biological aging states, leading to different individual risk profiles. Capturing this individual variance could constitute an even more powerful predictor enhancing prediction in age-related morbidity. Applying a nonlinear regression technique, we constructed a metabonomic measurement for biological age, the metabolic age score, based on urine data measured via (1)H NMR spectroscopy. We validated the score in two large independent population-based samples by revealing its significant associations with chronological age and age-related clinical phenotypes as well as its independent predictive value for survival over approximately 13 years of follow-up. Furthermore, the metabolic age score was prognostic for weight loss in a sample of individuals who underwent bariatric surgery. We conclude that the metabolic age score is an informative measurement of biological age with possible applications in personalized medicine.

Individual Education Plan Goals and Services for Adolescents with Autism: Impact of Age and Educational Setting

Science.gov (United States)

Kurth, Jennifer; Mastergeorge, Ann M.

2010-01-01

The purpose of this study is to describe the educational programs for adolescents with autism (age 12-16 years) in inclusion and noninclusion settings as reflected in their Individual Education Plan (IEP) goals, services, and curricular adaptations. Students who were included in general education math and language arts instruction had fewer…

Individual Differences in Components of Reaction Time Distributions and Their Relations to Working Memory and Intelligence

Science.gov (United States)

Schmiedek, Florian; Oberauer, Klaus; Wilhelm, Oliver; Suss, Heinz-Martin; Wittmann, Werner W.

2007-01-01

The authors bring together approaches from cognitive and individual differences psychology to model characteristics of reaction time distributions beyond measures of central tendency. Ex-Gaussian distributions and a diffusion model approach are used to describe individuals' reaction time data. The authors identified common latent factors for each…

Individual differences in behavioural plasticities.

Science.gov (United States)

Stamps, Judy A

2016-05-01

Interest in individual differences in animal behavioural plasticities has surged in recent years, but research in this area has been hampered by semantic confusion as different investigators use the same terms (e.g. plasticity, flexibility, responsiveness) to refer to different phenomena. The first goal of this review is to suggest a framework for categorizing the many different types of behavioural plasticities, describe examples of each, and indicate why using reversibility as a criterion for categorizing behavioural plasticities is problematic. This framework is then used to address a number of timely questions about individual differences in behavioural plasticities. One set of questions concerns the experimental designs that can be used to study individual differences in various types of behavioural plasticities. Although within-individual designs are the default option for empirical studies of many types of behavioural plasticities, in some situations (e.g. when experience at an early age affects the behaviour expressed at subsequent ages), 'replicate individual' designs can provide useful insights into individual differences in behavioural plasticities. To date, researchers using within-individual and replicate individual designs have documented individual differences in all of the major categories of behavioural plasticities described herein. Another important question is whether and how different types of behavioural plasticities are related to one another. Currently there is empirical evidence that many behavioural plasticities [e.g. contextual plasticity, learning rates, IIV (intra-individual variability), endogenous plasticities, ontogenetic plasticities) can themselves vary as a function of experiences earlier in life, that is, many types of behavioural plasticity are themselves developmentally plastic. These findings support the assumption that differences among individuals in prior experiences may contribute to individual differences in behavioural

Population dynamics of minimally cognitive individuals. Part 2: Dynamics of time-dependent knowledge

Energy Technology Data Exchange (ETDEWEB)

Schmieder, R.W.

1995-07-01

The dynamical principle for a population of interacting individuals with mutual pairwise knowledge, presented by the author in a previous paper for the case of constant knowledge, is extended to include the possibility that the knowledge is time-dependent. Several mechanisms are presented by which the mutual knowledge, represented by a matrix K, can be altered, leading to dynamical equations for K(t). The author presents various examples of the transient and long time asymptotic behavior of K(t) for populations of relatively isolated individuals interacting infrequently in local binary collisions. Among the effects observed in the numerical experiments are knowledge diffusion, learning transients, and fluctuating equilibria. This approach will be most appropriate to small populations of complex individuals such as simple animals, robots, computer networks, agent-mediated traffic, simple ecosystems, and games. Evidence of metastable states and intermittent switching leads them to envision a spectroscopy associated with such transitions that is independent of the specific physical individuals and the population. Such spectra may serve as good lumped descriptors of the collective emergent behavior of large classes of populations in which mutual knowledge is an important part of the dynamics.

Aging fatherhood in Finland - first-time fathers in Finland from 1987 to 2009.

Science.gov (United States)

Paavilainen, Miia; Bloigu, Aini; Hemminki, Elina; Gissler, Mika; Klemetti, Reija

2016-06-01

The increase in maternal age has been well documented in Western societies, but information on paternal age trends is scarce. The aim of this study was to investigate changes in age and other background characteristics of first-time fathers in Finland in the period 1987-2009. A random 60% sample of first-time fathers in each year from 1987 to 2009 was obtained from Statistics Finland (n=344,529). Five-year intervals were used (three years in 1987-1989). Sociodemographic characteristics of older first-time fathers (⩾40 years) were compared over time using logistic regression. In the logistic regression, immigrants were excluded from the study population as they may have had children before migrating to Finland. The mean age of first-time fathers increased from 28.7 to 30.4 years in 1987-2009. The change was greatest in the Capital Region and smallest in Northern and Eastern Finland. Fatherhood at the age of ⩾40 years doubled from 3.1% to 6.8%. From 2005 to 2009, men who lived in rural areas and the Capital Region, had a long education, were divorced or widowed, had been born in a rural area and were native Finnish speakers, were more likely than other men to be old when they became fathers. CONCLUSIONS DURING THE STUDY PERIOD, THE AVERAGE AGE OF FIRST-TIME FATHERS INCREASED BY TWO YEARS FURTHER STUDIES ARE NEEDED TO EXAMINE WHETHER DELAYS IN FIRST-TIME FATHERHOOD AFFECT FERTILITY, CHILD HEALTH AND THE USE OF SOCIAL AND HEALTH SERVICES. © 2015 the Nordic Societies of Public Health.

Nutritional status in edentulous people as compared to age matched dentate individuals-a cross-sectional study

Directory of Open Access Journals (Sweden)

Sukhabogi Jagadeeswara Rao

2013-01-01

Full Text Available Objectives: To assess the nutritional status in completely edentulous subjects and to compare with age matched dentate individuals. Materials and Method: The study was carried out in 60 individuals divided into two groups. Group one consisted of 30 edentulous subjects and 30 dentate individuals formed the second group Body Mass Index (BMI, serum albumin and hemoglobin values were analyzed in both the groups. Independent sample t- test was employed to check for the difference between the groups and Pearson′s correlation was done to ascertain the association between the variables within the groups. Results: There was a significant difference in all the biomarkers evaluated in between the groups. The values were negatively correlated with the period of edentulism within the groups. Conclusion: Edentulous people had lower nutritional values than their dentate counterparts and maintaining a healthy and normal dentition may have significant bearing on the overall health of an individual. body mass index, serum albumin, malnutrition, edentulous, dental status

The Effects of Dinner-to-Bed Time and Post-Dinner Walk on Gastric Cancer Across Different Age Groups: A Multicenter Case-Control Study in Southeast China.

Science.gov (United States)

Xu, Le; Zhang, Xi; Lu, Jun; Dai, Jia-Xi; Lin, Ren-Qin; Tian, Fang-Xi; Liang, Bing; Guo, Yi-Nan; Luo, Hui-Yu; Li, Ni; Fang, Dong-Ping; Zhao, Ruo-Hua; Huang, Chang-Ming

2016-04-01

Gastric cancer (GC) remains a major killer throughout the world. Despite the dramatic decrease in GC over the last century, its etiology has not yet been well characterized. This study investigated the possible independent and combined effects of the dinner-to-bed time and post-dinner walk on the risk for GC across different age groups. A population-based, case-control study was conducted in southeast China, including 452 patients with GC and 465 age-, race-, and gender-matched controls. A self-designed questionnaire was used to collect information on demographic characteristics, dinner-to-bed time, post-dinner walk, and other behavioral factors. Conditional logistic regression models were used to estimate the effects of the dinner-to-bed time and post-dinner walk as well as their joint effect on the risk for GC across different age groups. Individuals with dinner-to-bed time 55 years old.

Selfie Aging Index: An Index for the Self-assessment of Healthy and Active Aging.

Science.gov (United States)

Gonçalves, Judite; Gomes, Maria Isabel; Fonseca, Miguel; Teodoro, Tomás; Barros, Pedro Pita; Botelho, Maria-Amália

2017-01-01

Governments across Europe want to promote healthy and active aging, as a matter of both public health and economic sustainability. Designing policies focused on the most vulnerable groups requires information at the individual level. However, a measure of healthy and active aging at the individual level does not yet exist. This paper develops the Selfie Aging Index (SAI), an individual-level index of healthy and active aging. The SAI is developed thinking about a tool that would allow each person to take a selfie of her aging status. Therefore, it is based entirely on self-assessed indicators. This paper also illustrates how the SAI may look like in practice. The SAI is based on the Biopsychosocial Assessment Model (MAB), a tool for the multidimensional assessment of older adults along three domains: biological, psychological, and social. Indicators are selected and their weights determined based on an ordered probit model that relates the MAB indicators to self-assessed health, which proxies healthy and active aging. The ordered probit model predicts the SAI based on the estimated parameters. Finally, predictions are rescaled to the 0-1 interval. Data for the SAI development come from the Study of the Aging Profiles of the Portuguese Population and the Survey of Health, Aging, and Retirement in Europe. The selected indicators are BMI, having difficulties moving around indoors and performing the activities of daily living, feeling depressed, feeling nervous, lacking energy, time awareness score, marital status, having someone to confide in, education, type of job, exercise, and smoking status. The model also determines their weights. Results shed light on various factors that contribute significantly to healthy and active aging. Two examples are mental health and exercise, which deserve more attention from individuals themselves, health-care professionals, and public health policy. The SAI has the potential to put the individual at the center of the healthy and

Development of brain synchronisation within school-age--individual analysis of resting (α) coherence in a longitudinal data set.

Science.gov (United States)

Gmehlin, Dennis; Thomas, Christine; Weisbrod, Matthias; Walther, Stephan; Resch, Franz; Oelkers-Ax, Rieke

2011-10-01

Given evidence that synchronisation of neuronal activity may be a correlate of cognition, we examined EEG coherence as function of age and inter-electrode distance in healthy children and adolescents in order to elucidate basic information for a better understanding of developmental disorders associated with deficits in cognitive functions. Based on a 64-channel eyes closed resting EEG we combined local and global coherence measures in order to reduce volume conduction and reference effects. We used a two point longitudinal design in order to analyze intraindividual change during school-age (n=40; 6-18 years). Coherence was analyzed within individually adjusted frequency bands and around iPF (= individual alpha peak frequency). Both local and global resting coherence was largest in the alpha range and particularly around iPF. Local synchronisation was larger in the left compared with the right hemisphere. Controlling for increases in iPF, synchronisation increased with age, with global changes being most pronounced in the alpha range. Moreover age-related changes suggest an earlier development in girls. Our data provides evidence that both local and global functional integration increases during normal development within school-age. This general pattern - combined with more specific effects of sex and frequency - may help to specify deviations in developmental disorders. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Inter-individual differences in how presentation modality affects verbal learning performance in children aged 5 to 16

NARCIS (Netherlands)

Meijs, Celeste; Hurks, Petra P M; Wassenberg, Renske; Feron, Frans J M; Jolles, Jelle

2016-01-01

This study examines inter-individual differences in how presentation modality affects verbal learning performance. Children aged 5 to 16 performed a verbal learning test within one of three presentation modalities: pictorial, auditory, or textual. The results indicated that a beneficial effect of

Aging induced changes on NEXAFS fingerprints in individual combustion particles

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V. Zelenay

2011-11-01

Full Text Available Soot particles can significantly influence the Earth's climate by absorbing and scattering solar radiation as well as by acting as cloud condensation nuclei. However, despite their environmental (as well as economic and political importance, the way these properties are affected by atmospheric processing of the combustion exhaust gases is still a subject of discussion. In this work, individual soot particles emitted from two different vehicles, a EURO 2 transporter, a EURO 3 passenger car, and a wood stove were investigated on a single-particle basis. The emitted exhaust, including the particulate and the gas phase, was processed in a smog chamber with artificial solar radiation. Single particle specimens of both unprocessed and aged soot were characterized using near edge X-ray absorption fine structure spectroscopy (NEXAFS and scanning electron microscopy. Comparison of NEXAFS spectra from the unprocessed particles and those resulting from exhaust photooxidation in the chamber revealed changes in the carbon functional group content. For the wood stove emissions, these changes were minor, related to the relatively mild oxidation conditions. For the EURO 2 transporter emissions, the most apparent change was that of carboxylic carbon from oxidized organic compounds condensing on the primary soot particles. For the EURO 3 car emissions oxidation of primary soot particles upon photochemical aging has likely contributed as well. Overall, the changes in the NEXAFS fingerprints were in qualitative agreement with data from an aerosol mass spectrometer. Furthermore, by taking full advantage of our in situ microreactor concept, we show that the soot particles from all three combustion sources changed their ability to take up water under humid conditions upon photochemical aging of the exhaust. Due to the selectivity and sensitivity of the NEXAFS technique for the water mass, also small amounts of water taken up into the internal voids of agglomerated

Delay of Gratification, Delay Discounting and their Associations with Age, Episodic Future Thinking, and Future Time Perspective.

Science.gov (United States)

Göllner, Lars M; Ballhausen, Nicola; Kliegel, Matthias; Forstmeier, Simon

2017-01-01

The delay of gratification (DoG) in children is widely investigated with an experimental procedure originally called the "marshmallow test," whereas the studies on self-regulation (SR) in adolescents and adults usually use self-report questionnaires. Delay discounting (DD) measures simplify the DoG procedure and focus on monetary rewards. The aim of this study was to investigate age differences in DoG and DD from childhood to old age using a test that is suitable for both children and adults. Furthermore, investigations were conducted on the association between DoG/DD and two future orientation constructs [future time perspective (FTP) and episodic future thinking (EFT)] as well as age differences in these constructs. Participants from five age groups (9-14, 18-25, 35-55, 65-80, 80+) participated in the study ( N = 96). While we found no age difference for DoG, DD was the lowest [i.e., self-control (SC) was the highest] in young/middle adults; however, it was the highest (i.e., SC was the lowest) in children and old/oldest adults. Furthermore, we found significant age differences for DD and FTP. As predicted, there were strong correlations between DoG and FTP and between DD and FTP, but not between DoG/DD and EFT. These results indicate that age differences in SR vary across the measures used. Individuals who generally think and act in a future-oriented manner have a stronger ability to delay gratification.

Toward a Generation Free of Tuberculosis: TB Disease and Infection in Individuals of College Age in the United States

Science.gov (United States)

Shah, N. S.; Flood-Bryzman, A.; Jeffries, C.; Scott, J.

2018-01-01

Objectives: To assess the magnitude of active TB disease and latent TB infection (LTBI) in young adults of college age. Participants: Individuals who were aged 18-24 years in 2011 were used as a proxy for college students. Methods: Active TB cases reported to the 2011 US National TB Surveillance System (NTSS) were included. LTBI prevalence was…

Ageing and life-time management in nuclear power stations - concept and examples

International Nuclear Information System (INIS)

Erve, M.; Tenckhoff, E.

1999-01-01

Knowledge, assessment and understanding of phenomena caused by ageing, together with systematic utilization and extension of the technical life-time of components and systems, are of critical importance to the safety and economy of electricity generation in nuclear power stations. Economic use can be optimized by integrated ageing and life-time management; it can also be used to improve performance characteristics. (orig.) [de

Influence of aging time on residual tritium in Pd beds

International Nuclear Information System (INIS)

Yang Jinshui; Zhang Zhi; Su Yongjun; Jing Wenyong; Du Jie

2012-01-01

The amount of tritium in Pd beds. which were initially loaded at room temperature with tritium at the atomic ratio of T/Pd≈0.65 and aged 1.66 years, 3.47 years and 5.94 years, respectively, was investigated by methods of deuterium exchange, thermal desorption and aqua regia dissolution. Obtained results show that after deuterium exchange and thermal desorption, about 99% of tritium is desorbed from Pd tritide. and the amount of residual tritium become in- creasing significantly as the aged time is increased. which is 3.99 × 10 -7 gT/gPd, 4. 97 × 10 -7 gT/gPd and 1.29 × 10 -6 gT/gPd respectively. The increasing amount of residual tritium could be attributed to the increase of interstitial form of tritium, resulting from increasing interstitial type defects induced by the migration of 3 He atoms in interstitial sites as a function of aged time. (authors)

Effect of ageing time and temperature on corrosion behaviour of aluminum alloy 2014

Science.gov (United States)

Gadpale, Vikas; Banjare, Pragya N.; Manoj, Manoranjan Kumar

2018-03-01

In this paper, the effect of corrosion behaviour of aluminium alloy 2014 were studied by potentiodynamic polarization in 1 mole of NaCl solution of aged sample. The experimental testing results concluded that, corrosion resistance of Aluminum alloy 2014 degraded with the increasing the temperature (150°C & 200°C) and time of ageing. Corroded surface of the aged specimens was tested under optical microscopes for microstructures for phase analysis. Optical micrographs of corroded surfaces showed general corrosion and pitting corrosion. The corrosion resistance of lower ageing temperature and lower ageing time is higher because of its fine distribution of precipitates in matrix phase.

The reaction times of drivers aged 20 to 80 during a divided attention driving.

Science.gov (United States)

Svetina, Matija

2016-11-16

Many studies addressing age-related changes in driving performance focus on comparing young vs. older drivers, which might lead to the biased conclusion that driving performance decreases only after the age of 65. The main aim of the study was to show that changes in driving performance are progressive throughout the adult years. A sample of 351 drivers aged 20 to 80 was assessed for their reaction times while driving between road cones. The drivers were exposed to 2 conditions varying according to task complexity. In single task conditions, the drivers performed a full stopping maneuver at a given signal; in dual task conditions, the drivers were distracted before the signal for stopping maneuver was triggered. Reaction times were compared across conditions and age groups. The results showed that both reaction times and variability of driving performance increased progressively between the ages of 20 and 80. The increase in both reaction times and variability was greater in the complex task condition. The high-performing quarter of elderly drivers performed equally well or better than younger drivers did. The data clearly supported the claim that driving performance changes steadily across age groups: both mean reaction time and interindividual variability progressively increase with age. In addition, a significant group of older drivers was identified who did not show the expected age-related decrease in performance. The findings have important implications, suggesting that in relation to driving, aging is a progressive phenomenon and may lead to variety of driving performance; age-related studies of driving performance should put more emphasis on investigating changes across the whole driver age range rather than only comparing younger and older drivers.

N-Back auditory test performance in normal individuals

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Vanessa Tomé Gonçalves

Full Text Available Abstract The working memory construct refers to the capacity to maintain information for a limited time. Objectives: To devise stimuli and adapt the 5-back test and to verify the effect of age in normal Brazilian individuals. Methods: 31 healthy adults (15 young adults and 16 older adults were evaluated by batteries of auditory stimuli to verify the inter-group differences (age effect in working memory span, total correct answers and intrusions, and the intra-group effect of type of stimulus. Results: There was no intra-group stimulus effect. Individuals from both groups processed di and tri-syllables similarly. No difference between groups (no age effect was observed for any N-Back parameters: total score, span, number of intrusions, in either di or tri-syllable presentation. Conclusion: the processing capacity of 5 elements in phonological working memory was not affected by age.

Individual Differences in Developmental Change: Quantifying the Amplitude and Heterogeneity in Cognitive Change across Old Age

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Nathalie Mella

2018-02-01

Full Text Available It is well known that cognitive decline in older adults is of smaller amplitude in longitudinal than in cross-sectional studies. Yet, the measure of interest rests generally with aggregated group data. A focus on individual developmental trajectories is rare, mainly because it is difficult to assess intraindividual change reliably. Individual differences in developmental trajectories may differ quantitatively (e.g., larger or smaller decline or qualitatively (e.g., decline vs improvement, as well as in the degree of heterogeneity of change across different cognitive domains or different tasks. The present paper aims at exploring, within the Geneva Variability Study, individual change across several cognitive domains in 92 older adults (aged 59–89 years at baseline over a maximum of seven years and a half. Two novel, complementary methods were used to explore change in cognitive performance while remaining entirely at the intra-individual level. A bootstrap based confidence interval was estimated, for each participant and for each experimental condition, making it possible to define three patterns: stability, increase or decrease in performance. Within-person ANOVAs were also conducted for each individual on all the tasks. Those two methods allowed quantifying the direction, the amplitude and the heterogeneity of change for each individual. Results show that trajectories differed widely among individuals and that decline is far from being the rule.

Altered postural control variability in older-aged individuals with a history of lateral ankle sprain.

Science.gov (United States)

Terada, Masafumi; Kosik, Kyle; Johnson, Nathan; Gribble, Phillip

2018-02-01

The current study aimed to examine postural control performance during a single-leg balance task in elderly individuals with and without a previous history of lateral ankle sprain (LAS). Eighteen adults with a previous history of LAS (mean age = 66 years old) and 12 healthy controls (mean age = 65 years old) were included in the study. Participants performed three trials of a single-leg balance task during an eyes-opened condition for 20-s. Center of pressure (COP) trajectories in the anteroposterior (AP) and mediolateral (ML) directions were collected with a force plate. The following postural control measures were calculated in the AP and ML directions: 1) Sample Entropy (SampEn); 2) Approximate Entropy (ApEn); 3) mean of Time-to-Boundary minima (mean TTB); and 4) COP velocity (COPV). Older-age participants with a history LAS exhibited lower ApEn-AP, SampEn-AP, and SampEn-ML values compared to healthy controls (p postural control patterns, less adaptability, and more difficulty maintaining COP during a single-leg balance task in adults with a previous history of LAS. Our data suggest that there is a need to consider history of musculoskeletal injury when evaluating factors for postural control and fall risk in the elderly. Future investigations are needed to assess the effect of LAS on age-related declines in postural control and discern associations between potential risk factors of fall-related injuries and LAS in an elderly population. Copyright © 2017 Elsevier B.V. All rights reserved.

Profound vision loss impairs psychological well-being in young and middle-aged individuals

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Garcia GA

2017-02-01

Full Text Available Giancarlo A Garcia,1,2 Matin Khoshnevis,1,3 Jesse Gale,1,4 Starleen E Frousiakis,1,5 Tiffany J Hwang,1,6 Lissa Poincenot,1 Rustum Karanjia,1,7–9 David Baron,6 Alfredo A Sadun1,7 1Doheny Eye Institute, Los Angeles, CA, USA; 2University of California, Irvine School of Medicine, Irvine, CA, USA; 3Department of Ophthalmology, Temple University, Philadelphia, PA, USA; 4Wellington School of Medicine and Health Sciences, University of Otago, Wellington, NZ; 5Department of Ophthalmology, New York Medical College, Valhalla, NY, USA; 6Department of Psychiatry & The Behavioral Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA; 7Doheny Eye Centers, Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles California, CA, USA; 8Department of Ophthalmology, University of Ottawa, Ottawa, ON, Canada; 9Ottawa Hospital Health Research Institute, Ottawa, ON, Canada Purpose: The aim of this study was to evaluate the effects of profound vision loss on psychological well-being in adolescents, young adults, and middle-aged adults with regard to mood, interpersonal interactions, and career-related goals. In addition, we assessed the significance of the resources that may be used to enhance psychological well-being in cases of profound vision loss, and in particular, examined the utility of low vision aids and the role of the ophthalmologist as a provider of emotional support.Methods: A questionnaire was issued to individuals aged 13–65 years with profound vision loss resulting from Leber’s hereditary optic neuropathy (LHON. Depression prevalence was evaluated with questions regarding major depressive disorder symptomatology. Participants appraised the effects of vision loss on their interpersonal interactions and career goals by providing an impact rating (IR on a 21-point psychometric scale from −10 to +10. Social well-being index was defined as the average of interpersonal IR and career IR

Part-time sick leave as a treatment method for individuals with musculoskeletal disorders

OpenAIRE

Andrén, Daniela; Svensson, Mikael

2009-01-01

There is increasing evidence that staying active is an important part of a recovery process for individuals on sick leave due to musculoskeletal disorders (MSDs). It has been suggested that using part-time sick-leave rather than full-time sick leave will enhance the possibility of full recovery to the workforce, and several countries actively favor this policy. However, to date only few studies have estimated the effect of using part-time sick leave in contrast to full-time sick leave. In thi...

The Evolution of the Age at Menarche from Prehistorical to Modern Times.

Science.gov (United States)

Papadimitriou, Anastasios

2016-12-01

Menarche denotes the onset of the female reproductive capacity. The age that menarche occurs is mostly attributed to the interaction of genetics and various environmental factors. Herein, the author describes the evolution of the age at menarche from prehistoric to the present times. Data from skeletal remains suggest that in the Paleolithic woman menarche occurred at an age between 7 and 13 years, early sexual maturation being a trade-off for reduced life expectancy. In the classical, as well as in the medieval years, the age at menarche was generally reported to be at approximately 14 years, with a range from 12 to 15 years. A significant retardation of the age at menarche occurred in the beginning of the modern times, soon after the industrial revolution, due to the deterioration of the living conditions, with most studies reporting menarche to occur at 15-16 years. In the 20th century, especially in the second half of it, in the industrialized countries, the age at menarche decreased significantly, as a result of the improvement of the socioeconomic conditions, occurring at 12-13 years. In the present times, in the developed countries, this trend seems to slow down or level off. Copyright © 2016 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.

Modeling the Phenotypic Architecture of Autism Symptoms from Time of Diagnosis to Age 6

Science.gov (United States)

Georgiades, Stelios; Boyle, Michael; Szatmari, Peter; Hanna, Steven; Duku, Eric; Zwaigenbaum, Lonnie; Bryson, Susan; Fombonne, Eric; Volden, Joanne; Mirenda, Pat; Smith, Isabel; Roberts, Wendy; Vaillancourt, Tracy; Waddell, Charlotte; Bennett, Teresa; Elsabbagh, Mayada; Thompson, Ann

2014-01-01

The latent class structure of autism symptoms from the time of diagnosis to age 6 years was examined in a sample of 280 children with autism spectrum disorder. Factor mixture modeling was performed on 26 algorithm items from the Autism Diagnostic Interview-Revised at diagnosis (Time 1) and again at age 6 (Time 2). At Time 1, a…

Influence of Individual Determinants on Physical Activity at Work and During Leisure Time in Soldiers: A Prospective Surveillance Study.

Science.gov (United States)

Schulze, Christoph; Lindner, Tobias; Goethel, Pauline; Müller, Marie; Mittelmeier, Wolfram; Bader, Rainer

2016-01-01

Quantified physical activity is an important parameter for evaluating the risk of the incidence of internal and musculoskeletal disorders. The objective of this study was to evaluate the physical activity of German Soldiers on duty and during leisure time with regard to individual determinants and to evaluate if factors associated with the risk of the incidence of internal or musculoskeletal disorders are of relevance for physical activity. For this purpose, we conducted activity measurements on 169 subjects. The accelerometer-based activity sensor was worn for 7 consecutive days. The number of steps taken was evaluated as an activity marker.We observed that a high body mass index and a large waist circumference were associated with a low activity level. Women were found to be more active than men, particularly during leisure time. Personnel under 25 years of age were more physically active than those between 25 and 50 years of age. Subjects with underlying musculoskeletal disorders were less active than those who had internal disorders or were healthy. Men and overweight people run a higher risk of developing musculoskeletal and internal disorders. Health promotion should focus on raising the physical activity level with the aim of exerting a positive influence on the associated risk factors.

Mortality in individuals with disruptive behavior disorders diagnosed by specialist services - A nationwide cohort study

DEFF Research Database (Denmark)

Scott, James G; Giørtz Pedersen, Marianne; Erskine, Holly E

2017-01-01

by specialist services were followed from their first birthday to 2013. Those with and without DBDs were compared using mortality rate ratios (MRRs) estimated using Poisson regression and adjusted for calendar period, age, sex, family history of psychiatric disorders, maternal age at time of birth, paternal age...... at time of birth, parental education status, and parental employment status. Over the course of follow up, which totalled 24.9 million person-years, 5580 cohort members died including 78 individuals with DBDs. The mortality rate per 10,000 person-years was 9.66 for individuals with DBDs compared to 2...

POSSIBILITIES OF TEACHERS FOR MONITORING, DETECTING AND RECORDING OF INDIVIDUAL CHARACTERISTICS OF STUDENTS IN EARLY SCHOOL AGE

Directory of Open Access Journals (Sweden)

Tatjana Koteva-mojsovska

2015-06-01

Full Text Available The monitoring and recording of the individual characteristics of children are very important for the development of quality education. Also the views of the teachers about the differences in the development, the potentials and the affinities of the children in the early school period are especially important. The quality education process in the modern school should be adapted to the individual potentials of the children. The children are individuals with their own integrity and characteristics. (Johnston and Halocha, 2010. They have individual pace and develop individual approaches in the learning process. This individual pace in the development of the children requires the teachers to regularly monitor and record the individual characteristics and differences of the children, monitoring the children’s interests, planning instruction which will adapt to the different learning approaches and the different pace of progress of the students.Setting out from this paradigm, this paper, which is based on a realized research, aims to offer findings about the treatment of the individual characteristics of the early school-age children in our country. According to this, we carried out a research in four primary schools in Skopje, which showed us that the teachers lack the appropriate conditions and possibilities to monitor and record the individual characteristics and the specific differences of the students in the early school period. 

Loss Aversion and Individual Characteristics

DEFF Research Database (Denmark)

Hjorth, Katrine; Fosgerau, Mogens

2011-01-01

Many studies have shown that loss aversion affects the valuation of non-market goods. Using stated choice data, this paper presents an empirical investigation of how individual-level loss aversion varies with observable personal characteristics and with the choice context. We investigate loss...... aversion with respect to travel time and money, and find significant loss aversion in both dimensions. The degree of loss aversion in the time dimension is larger than in the money dimension, and depends on age and education. Subjects tend to be more loss averse when the reference is well established....

Subjective age and personality development: a 10-year study.

Science.gov (United States)

Stephan, Yannick; Sutin, Angelina R; Terracciano, Antonio

2015-04-01

Personality theory and research typically focus on chronological age as a key indicator of personality development. This study examines whether the subjective experience of age is an alternative marker of the biomedical and psychosocial factors that contribute to individual differences in personality development. The present study uses data from the Midlife in the United States longitudinal survey (N = 3,617) to examine how subjective age is associated with stability and change in personality and the dynamic associations between subjective age and personality traits over a 10-year period. Regression analyses indicated that a younger subjective age at baseline was associated with increases in Openness, Conscientiousness, and Agreeableness; correlated changes were also found. The rank-order stability of Extraversion and Openness and overall profile consistency were higher among those with a younger subjective age at baseline and were also associated with the rate of subjective aging over time. The present study reveals that beyond chronological age, the age an individual feels is related to changes in characteristic ways of thinking, feeling, and behaving over time. © 2014 Wiley Periodicals, Inc.

The effect of individual upper alpha band enhancing neurofeedbac kon reaction-time as an indicator of short-term memory in women employee’s

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Mersedeh Jahanseir

2014-11-01

Full Text Available Background: In neurofeedback systems, people are able to reinforce or hinder their basic EEG rhythms according to operant conditioninin recent studies the effect of neurofeedback training on improvement of working memory has been shown on the healthy subjects. Disadvantage of neurofeedback is the high number of training sessions and high cost. In previous studies, alpha band power within (8-12 Hz has been considered for all subjects. Previous research reached the conclusion that by using individual upper alpha in neurofeedback, learning rate will increase, so the training sessions and the cost of training will be reduced. Material and Methods: In this study, all participants were female, 10 adults (10 women, mean age 33.8 years, SD=3.56 years. Randomly assigned to control and test group, five in test group and five in control group. Each subject performed the memory test four times, two times before the start of the first neurofeedback training and two times after the end of the last neurofeedback session. Eight training sessions were held, each session had three trials. Results: Discriminate response to the color of the drawing, as well as reaction time hadsignificant effects for test group (p0.05. Before and after eight training sessions by individual upper alpha power neurofeedback, reaction time of discriminate response to the color of the drawing for test group decreased and had significant effects (p0.05. Conclusion: Increasing relative individual upper alpha power, caused by neurofeedback training during eight sessions, indicated that this method increases the memory of women employees, and improves the ability of discriminative response to the color (red & green of the drawing as well as reducing reaction time.

Delay of Gratification, Delay Discounting and their Associations with Age, Episodic Future Thinking, and Future Time Perspective

Directory of Open Access Journals (Sweden)

Lars M. Göllner

2018-01-01

Full Text Available The delay of gratification (DoG in children is widely investigated with an experimental procedure originally called the “marshmallow test,” whereas the studies on self-regulation (SR in adolescents and adults usually use self-report questionnaires. Delay discounting (DD measures simplify the DoG procedure and focus on monetary rewards. The aim of this study was to investigate age differences in DoG and DD from childhood to old age using a test that is suitable for both children and adults. Furthermore, investigations were conducted on the association between DoG/DD and two future orientation constructs [future time perspective (FTP and episodic future thinking (EFT] as well as age differences in these constructs. Participants from five age groups (9–14, 18–25, 35–55, 65–80, 80+ participated in the study (N = 96. While we found no age difference for DoG, DD was the lowest [i.e., self-control (SC was the highest] in young/middle adults; however, it was the highest (i.e., SC was the lowest in children and old/oldest adults. Furthermore, we found significant age differences for DD and FTP. As predicted, there were strong correlations between DoG and FTP and between DD and FTP, but not between DoG/DD and EFT. These results indicate that age differences in SR vary across the measures used. Individuals who generally think and act in a future-oriented manner have a stronger ability to delay gratification.

Forecasting the timing of peak mandibular growth in males by using skeletal age.

Science.gov (United States)

Hunter, W Stuart; Baumrind, Sheldon; Popovich, Frank; Jorgensen, Gertrud

2007-03-01

It is generally believed that the orthodontic treatment of a patient with a Class II malocclusion and a small mandible is enhanced by good growth at puberty, so that the timing of peak mandibular growth at puberty becomes of interest. To test the belief that skeletal age, whether early, average, or late, can be used to predict the timing of maximum growth of the mandible, whether early, average, or late, the predictive relationship between skeletal age and peak mandibular growth velocity (PMdV) at puberty was evaluated in 94 boys by using their longitudinal records from 4 to 18 years of age. Skeletal age was determined for each subject at ages 9 through 14 by using the method of Greulich and Pyle. At age 9, the Greulich and Pyle measurements predicted that 30 of the 94 subjects would have delayed PMdV equal to or exceeding 1 SD (of the mean age for PMdV), and 10 would have advanced PMdV equal to or exceeding 1 SD. When the actual age of PMdV was determined retrospectively from plots of annual mandibular growth increments, it was found that only 4 of the 30 in the delayed group had actually experienced delays in PMdV, and only 2 of the 10 in the advanced group had experienced accelerated PMdV. Skeletal age is not a reliable predictor of the timing of PMdV.

Thermal comfort. Individual and time-dependent?; Thermisch comfort. Individueel en tijdafhankelijk?

Energy Technology Data Exchange (ETDEWEB)

Noom, P.; Zeiler, W.; Boxem, G. [Unit Building Physics and Systems, Faculteit Bouwkunde, Technische Universiteit Eindhoven TUE, Eindhoven (Netherlands); Haan, J.F.B.C.; Van der Velden, J. [Kropman Installatietechniek, Rijswijk (Netherlands)

2010-11-15

With respect to the perceived thermal comfort there are large individual differences, which also change during daytime. Therefore is worthwhile to determine the individual thermal comfort profiles during the day. The perceived thermal comfort level follows an individual day profile. By using these profiles as a leading principal to control the indoor temperatures an improvement of the perceived comfort is possible while at the same time it can reduce energy consumption. [Dutch] Nieuwe optimalisatiemogelijkheden voor energiegebruik voor het comfort zijn mogelijk door vanuit de actuele en toekomstige individuele behoefte aan comfort van de gebruiker de installatie optimaal aan te sturen. Dit artikel geeft inzicht in de efficiente afstemming van vraag en aanbod van energie voor thermisch comfort. In een kantoorgebouw zijn metingen gedaan, conform NEN-EN-ISO 7726 (Ergonomics of the thermal environment. Instruments for measuring physical quantities), en er is een enquete gehouden om het thermisch comfort individueel te kunnen bepalen gedurende de werkdag. Het doel van de metingen was de verschillen tussen de individuele beleving en de werkelijke klimaat omstandigheden te kunnen bepalen.

Radiosensitivity of different aged human lymphocytes following electron irradiation in vitro

International Nuclear Information System (INIS)

Joksic, G.; Nikolic, M.; Spasojevic-Tisma, V.

1997-01-01

Cytochalasin B-blocking micronucleus test and chromosomal aberration analysis were used in this study to estimate the yield of individual variability in radiation response of different aged human lymphocytes. Both analyses were performed in three groups of adults, aged 18-65 years, on two sampling times, following irradiation by therapeutical dose of 2 G in vitro. No statistically significant difference in the induced yield of exchange aberrations between individuals under consideration was found. The yield of total aberration data showed greater variability and was statistically significant in the oldest group against two other adult groups. Regarding to fixation times no statistically significant differences in the induced yield of chromosomal aberration (exchanges as well as total aberrations) were observed. The study has shown a slight increase in spontaneously occurring micronuclei with age. Almost equal mean number of radiation induced micronuclei was observed in the groups of adult aged 18-20 and 45-55 years. The highest mean number was observed in the oldest group. Evident variation in number of radiation induced micronuclei among individuals from the same age group was observed. The results of micronuclei assay for for all individuals under consideration show statistically significant difference in the yield of radiation-induced micronuclei regarding the second fixation time. This study has shown that cytochalasin-B blocking micronucleus test is more sensitive assay than chromosomal aberration analysis for the estimation of individual radiosensitivity. (author)

Time perspective: its link to personality traits, age, and gender

OpenAIRE

Kairys, Antanas

2010-01-01

In Lithuania, as well as in other countries, psychological studies on time perspective are still making their first steps. Currently, no theoretical paradigm is extensive enough to serve well as a basis for further fundamental and applied research in this field. The goal of this study was to explore the link between time perspective and personality traits in different gender and age groups. To analyse time perspective and personality traits, two independent studies were carried out (N=636 in ...

Relation between Motivational Factors, Age, and Gender of Individuals Participating in a Swimming Project

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Alejandro Rodriguez Montero

2014-08-01

Full Text Available The purpose of this study was to determine the relationship between motivational factors, sex and age on the participants at a project of swimming. The study included 107 subjects (71% of the total of active participants in the project, of which 51 were men and 56 women, aged between 18 and 63 years (36,27 ± 10,67. The sample was divided into four age categories (18-29 years, 30-39 years, 40-49 years and 50 and over and by sex. To know the reasons that lead people to engage physical exercise, self-report questionnaire Motives for the Practice of Physical Exercises (AMPEF, adapted by and Pintanel Niñerola Capdevila (2004 was applied. The results of the individual analysis showed that the factors: positive health and prevention; well-being and fun; muscular strength and endurance are important reasons for both men and women in all age categories, with values ≥ 7 (between 1 to 10. There were no significant differences in the total score between variables. The data reported are consistent with those reported in the literature. It is concluded that the main reasons for people to be physically active are: health, fun, well-being and improvement of physical, also found significant differences in the reasons relating to the challenge and competition between men and women, results also agree with previous publications.

Gender Differences in Vocational Rehabilitation Service Predictors of Successful Competitive Employment for Transition-Aged Individuals with Autism

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Sung, Connie; Sánchez, Jennifer; Kuo, Hung-Jen; Wang, Chia-Chiang; Leahy, Michael J.

2015-01-01

As males and females with autism spectrum disorder (ASD) experience different symptomology, their needs for vocational rehabilitation (VR) are unique as they transition into adulthood. This study examined the effects of gender differences in VR service predictors on employment outcomes for transition-aged individuals with ASD. A total of 1696…

Individual monitoring and dosimetry: The Goiania experience

International Nuclear Information System (INIS)

Lipsztein, J.L.; Melo, D.R.; Oliveira, C.A.N.; Bertelli, L.

2000-01-01

Several people were contaminated with 137 Cs in an accident involving the stealing and breaching of a radiotherapy source in Goiania, Brazil. A drug known as Prussian Blue was administered to some contaminated individuals to enhance Cs elimination from the body. Individuals internally contaminated were monitored for the two first months, exclusively by in vitro bioassay, i.e., urine and faeces analysis. After that period of time a field whole-body counter was set up in Goiania and individuals started to be monitored in vivo, on a regular basis. The total internal committed doses and the effect of Prussian blue treatment have been evaluated. For adults, the biological half-time (T 2 ) under PB treatment was reduced to an average value around to 31% of the half-time after finished treatment. For adolescents (T 2 ) was reduced to an average value around to 54% and for children was reduced to an average value around to 57%. A weight dependent biokinetic study of 137 Cs retention in humans was conducted. Data from 10 girls and 7 boys, aged 1 to 10 y old, as well as from 10 adolescents: 4 females and 6 males, and from 30 adults: 15 females and 15 males, contaminated in the accident, were used in this study. A planned experiment with beagle dogs were carried out to furnish some further data for our study. Based on these data, a three terms exponential equation is suggested to describe the 137 Cs retention in the body, the first-term associated with a very short half-time, the second with a longer half-time and the third term with a very long half-time, of the order of 400 to 570 days and relating to a retention fraction of only 0.1%. A table of weight, age and sex specific half-times for the second term is suggested. (author)

Prevalence of cognitive impairment in individuals aged over 65 in an urban area: DERIVA study

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Rodríguez-Sánchez Emiliano

2011-11-01

Full Text Available Abstract Background Few data are available on the prevalence of cognitive impairment (CI in Spain, and the existing information shows important variations depending on the geographical setting and the methodology employed. The aim of this study was to determine the prevalence of CI in individuals aged over 65 in an urban area, and to analyze its associated risk factors. Methods Design: A descriptive, cross-sectional, home questionnaire-based study; Setting: Populational, urban setting. Participants: The reference population comprised over-65s living in the city of Salamanca (Spain in 2009. Randomized sampling stratified according to health district was carried out, and a total of 480 people were selected. In all, 327 patients were interviewed (68.10%, with a mean age of 76.35 years (SD: 7.33. Women accounted for 64.5% of the total. Measurements: A home health questionnaire was used to obtain the following data: age, sex, educational level, family structure, morbidity and functionality. All participants completed a neuropsychological test battery. The prevalence data were compared with those of the European population, with direct adjustment for age and sex. Diagnoses were divided into three general categories: normal cognitive function, cognitive impairment - no dementia (CIND, and dementia. Results The prevalence of CI among these over-65s was 19% (14.7% CIND and 4.3% dementia. The age-and sex-adjusted global prevalence of CI was 14.9%. CI increased with age (p Conclusions The observed raw prevalence of CI was 19% (14.9% after adjusting for age and sex. Older age and the presence of diabetes and anxiety-depression increased the risk of CI, while higher educational level reduced the risk.

Mean-Variance portfolio optimization when each asset has individual uncertain exit-time

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Reza Keykhaei

2016-12-01

Full Text Available The standard Markowitz Mean-Variance optimization model is a single-period portfolio selection approach where the exit-time (or the time-horizon is deterministic. ‎In this paper we study the Mean-Variance portfolio selection problem ‎with ‎uncertain ‎exit-time ‎when ‎each ‎has ‎individual uncertain ‎xit-time‎, ‎which generalizes the Markowitz's model‎. ‎‎‎‎‎‎We provide some conditions under which the optimal portfolio of the generalized problem is independent of the exit-times distributions. Also, ‎‎it is shown that under some general circumstances, the sets of optimal portfolios‎ ‎in the generalized model and the standard model are the same‎.

Age structure changes and extraordinary lifespan in wild medfly populations.

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Carey, James R; Papadopoulos, Nikos T; Müller, Hans-Georg; Katsoyannos, Byron I; Kouloussis, Nikos A; Wang, Jane-Ling; Wachter, Kenneth; Yu, Wei; Liedo, Pablo

2008-06-01

The main purpose of this study was to test the hypotheses that major changes in age structure occur in wild populations of the Mediterranean fruit fly (medfly) and that a substantial fraction of individuals survive to middle age and beyond (> 3-4 weeks). We thus brought reference life tables and deconvolution models to bear on medfly mortality data gathered from a 3-year study of field-captured individuals that were monitored in the laboratory. The average time-to-death of captured females differed between sampling dates by 23.9, 22.7, and 37.0 days in the 2003, 2004, and 2005 field seasons, respectively. These shifts in average times-to-death provided evidence of changes in population age structure. Estimates indicated that middle-aged medflies (> 30 days) were common in the population. A surprise in the study was the extraordinary longevity observed in field-captured medflies. For example, 19 captured females but no reference females survived in the laboratory for 140 days or more, and 6 captured but no reference males survived in the laboratory for 170 days or more. This paper advances the study of aging in the wild by introducing a new method for estimating age structure in insect populations, demonstrating that major changes in age structure occur in field populations of insects, showing that middle-aged individuals are common in the wild, and revealing the extraordinary lifespans of wild-caught individuals due to their early life experience in the field.

Snacking now or later? Individual differences in following intentions or habits explained by time perspective

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Onwezen, M.C.; Riet, van 't J.; Dagevos, H.; Sijtsema, S.J.; Snoek, H.M.

2016-01-01

Even when individuals are aware of long-term health effects of their diet, and form healthy intentions, they often engage in relatively unhealthy snacking habits. Some individuals fall back on unhealthy habits more easily than others. We aim to explore whether time perspective can explain why

Snacking now or later? Individual differences in following intentions or habits explained by time perspective

NARCIS (Netherlands)

Onwezen, M.C.; Riet, J.P. van 't; Dagevos, H.; Sijtsema, S.J.; Snoek, H.M.

2016-01-01

Even when individuals are aware of long-term health effects of their diet, and form healthy intentions, they often engage in relatively unhealthy snacking habits. Some individuals fall back on unhealthy habits more easily than others. We aim to explore whether time perspective can explain why some

System Models and Aging: A Driving Example.

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Melichar, Joseph F.

Chronological age is a marker in time but it fails to measure accurately the performance or behavioral characteristics of individuals. This paper models the complexity of aging by using a system model and a human function paradigm. These models help facilitate representation of older adults, integrate research agendas, and enhance remediative…

Patterns and sources of personality development in old age.

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Kandler, Christian; Kornadt, Anna E; Hagemeyer, Birk; Neyer, Franz J

2015-07-01

Despite abundant evidence that personality development continues in adulthood, little is known about the patterns and sources of personality development in old age. We thus investigated mean-level trends and individual differences in change as well as the genetic and environmental sources of rank-order continuity and change in several personality traits (neuroticism, extraversion, openness, agreeableness, conscientiousness, perceived control, and affect intensity) and well-being. In addition, we analyzed the interrelation between perceived control and change in other personality traits as well as between change in personality traits and change in well-being. We analyzed data from older adult twins, aged 64-85 years at Time 1 (N = 410; 135 males and 275 females; 134 monozygotic and 63 dizygotic twin pairs), collected at 2 different time points about 5 years apart. On average, neuroticism increased, whereas extraversion, conscientiousness, and perceived control significantly decreased over time. Change in perceived control was associated with change in neuroticism and conscientiousness, pointing to particular adaptation mechanisms specific to old age. Whereas individual differences in personality traits were fairly stable due to both genetic and environmental sources, individual differences in change were primarily due to environmental sources (beyond random error) indicating plasticity in old age. Even though the average level of well-being did not significantly change over time, individual well-being tended to decrease with strongly increasing levels of neuroticism as well as decreasing extraversion, conscientiousness, and perceived control, indicating that personality traits predict well-being but not vice versa. We discuss implications for theory on personality development across the lifespan. (c) 2015 APA, all rights reserved).

Age-Related Intraindividual Performance Variability with Practice

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Miller, Suzanne Bonneau; Odell, Katharine H.

2007-01-01

Fluctuations in cognitive task performance in older individuals have been reported. To examine intraindividual variability as a function of practice, 34 younger and 34 older female participants, aged 20-30 years and 70-82 years, respectively, performed a reading span task 16 times over four sessions. Each individual's recall accuracy was analyzed…

Drusen volume development over time and its relevance to the course of age-related macular degeneration.

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Schlanitz, Ferdinand G; Baumann, Bernhard; Kundi, Michael; Sacu, Stefan; Baratsits, Magdalena; Scheschy, Ulrike; Shahlaee, Abtin; Mittermüller, Tamara J; Montuoro, Alessio; Roberts, Philipp; Pircher, Michael; Hitzenberger, Christoph K; Schmidt-Erfurth, Ursula

2017-02-01

To quantify the change in drusen volume over time and identify its prognostic value for individual risk assessment. A prospective observational study over a minimum of 3 years and maximum of 5 years and follow-up examination every 3 months was conducted at the ophthalmology department of the Medical University of Vienna. 109 patients presenting early and intermediate age-related macular degeneration (AMD) were included, of which 30 patients concluded a regular follow-up for at least 3 years. 50 eyes of 30 patients were imaged every 3 months using spectral-domain and polarisation-sensitive optical coherence tomography (OCT). Drusen volume was measured using an automated algorithm. Data of a 6-month follow-up were segmented manually by expert graders. Gradings from 24 000 individual B-scans showed solid correlation between manual and automated segmentation with an initial mean drusen volume of 0.17 mm 3 . The increase in drusen volume was shown to be comparable among all eyes, and a model for long-term drusen volume development could be fitted as a cubic polynomial function and an R 2 =0.955. Spontaneous drusen regression was observed in 22 of 50 eyes. In this group, four eyes developed choroidal neovascularisation and three geographic atrophy. Drusen volume increase over time can be described by a cubic function. Spontaneous regression appears to precede conversion to advanced AMD. OCT might be a promising tool for predicting the individual risk of progression of AMD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Balance impairment in individuals with Wolfram syndrome.

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Pickett, Kristen A; Duncan, Ryan P; Paciorkowski, Alex R; Permutt, M Alan; Marshall, Bess; Hershey, Tamara; Earhart, Gammon M

2012-07-01

Wolfram syndrome (WFS), a rare neurodegenerative disorder, is characterized by early onset insulin-dependent diabetes mellitus, optic atrophy, deafness, diabetes insipidus, and neurological abnormalities. Although previously unreported, we hypothesized that neurological complications may be detectable in relatively early stages of the disease. As the cerebellum and brainstem seem particularly vulnerable in WFS, we focused on balance functions critically dependent on these regions. The primary goal of this investigation was to compare balance in young individuals with WFS, in relatively early stages of the disease, to an age-matched cohort using a clinically applicable test. Balance was assessed via the mini-BESTest in 13 children, adolescents and young adults with WFS and 30 typically developing age-matched individuals. A significant difference was observed between groups in balance as well as in three of four subcomponents of the mini-BESTest and in two timed tasks related to balance. Mini-BESTest scores were correlated with age among typically developing individuals. In the WFS group, mini-BESTest scores were related to overall motor dysfunction, but not age. Impairments in balance in WFS may occur earlier in the disease process than previously recognized and appear to be related to overall neurological progression rather than chronological age. Recognizing balance impairments and understanding which balance systems contribute to balance deficits in those with WFS may allow for development of effective patient-centered treatment paradigms. Copyright © 2012 Elsevier B.V. All rights reserved.

Effect of Forest Walking on Autonomic Nervous System Activity in Middle-Aged Hypertensive Individuals: A Pilot Study

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Chorong Song

2015-03-01

Full Text Available There has been increasing attention on the therapeutic effects of the forest environment. However, evidence-based research that clarifies the physiological effects of the forest environment on hypertensive individuals is lacking. This study provides scientific evidence suggesting that a brief forest walk affects autonomic nervous system activity in middle-aged hypertensive individuals. Twenty participants (58.0 ± 10.6 years were instructed to walk predetermined courses in forest and urban environments (as control. Course length (17-min walk, walking speed, and energy expenditure were equal between the forest and urban environments to clarify the effects of each environment. Heart rate variability (HRV and heart rate were used to quantify physiological responses. The modified semantic differential method and Profile of Mood States were used to determine psychological responses. The natural logarithm of the high-frequency component of HRV was significantly higher and heart rate was significantly lower when participants walked in the forest than when they walked in the urban environment. The questionnaire results indicated that, compared with the urban environment, walking in the forest increased “comfortable”, “relaxed”, “natural” and “vigorous” feelings and decreased “tension-anxiety,” “depression,” “anxiety-hostility,” “fatigue” and “confusion”. A brief walk in the forest elicited physiological and psychological relaxation effects on middle-aged hypertensive individuals.

Correlates of adolescent sleep time and variability in sleep time: the role of individual and health related characteristics.

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Moore, Melisa; Kirchner, H Lester; Drotar, Dennis; Johnson, Nathan; Rosen, Carol; Redline, Susan

2011-03-01

Adolescents are predisposed to short sleep duration and irregular sleep patterns due to certain host characteristics (e.g., age, pubertal status, gender, ethnicity, socioeconomic class, and neighborhood distress) and health-related variables (e.g., ADHD, asthma, birth weight, and BMI). The aim of the current study was to investigate the relationship between such variables and actigraphic measures of sleep duration and variability. Cross-sectional study of 247 adolescents (48.5% female, 54.3% ethnic minority, mean age of 13.7years) involved in a larger community-based cohort study. Significant univariate predictors of sleep duration included gender, minority ethnicity, neighborhood distress, parent income, and BMI. In multivariate models, gender, minority status, and BMI were significantly associated with sleep duration (all pminority adolescents, and those of a lower BMI obtaining more sleep. Univariate models demonstrated that age, minority ethnicity, neighborhood distress, parent education, parent income, pubertal status, and BMI were significantly related to variability in total sleep time. In the multivariate model, age, minority status, and BMI were significantly related to variability in total sleep time (all pminority adolescents, and those of a lower BMI obtaining more regular sleep. These data show differences in sleep patterns in population sub-groups of adolescents which may be important in understanding pediatric health risk profiles. Sub-groups that may particularly benefit from interventions aimed at improving sleep patterns include boys, overweight, and minority adolescents. Copyright © 2011 Elsevier B.V. All rights reserved.

Depression and Anxiety Change from Adolescence to Adulthood in Individuals with and without Language Impairment.

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Botting, Nicola; Toseeb, Umar; Pickles, Andrew; Durkin, Kevin; Conti-Ramsden, Gina

2016-01-01

This prospective longitudinal study aims to determine patterns and predictors of change in depression and anxiety from adolescence to adulthood in individuals with language impairment (LI). Individuals with LI originally recruited at age 7 years and a comparison group of age-matched peers (AMPs) were followed from adolescence (16 years) to adulthood (24 years). We determine patterns of change in depression and anxiety using the Child Manifest Anxiety Scale-Revised (CMAS-R) and Short Moods and Feelings Questionnaire (SMFQ). In addition to examining associations with gender, verbal and nonverbal skills, we use a time-varying variable to investigate relationships between depression and anxiety symptoms and transitions in educational/employment circumstances. The results show that anxiety was higher in participants with LI than age matched peers and remained so from adolescence to adulthood. Individuals with LI had higher levels of depression symptoms than did AMPs at 16 years. Levels in those with LI decreased post-compulsory schooling but rose again by 24 years of age. Those who left compulsory school provision (regardless of school type) for more choice-driven college but who were not in full-time employment or study by 24 years of age were more likely to show this depression pathway. Verbal and nonverbal skills were not predictive of this pattern of depression over time. The typical female vulnerability for depression and anxiety was observed for AMPs but not for individuals with LI. These findings have implications for service provision, career/employment advice and support for individuals with a history of LI during different transitions from adolescence to adulthood.

Depression and Anxiety Change from Adolescence to Adulthood in Individuals with and without Language Impairment.

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Nicola Botting

Full Text Available This prospective longitudinal study aims to determine patterns and predictors of change in depression and anxiety from adolescence to adulthood in individuals with language impairment (LI. Individuals with LI originally recruited at age 7 years and a comparison group of age-matched peers (AMPs were followed from adolescence (16 years to adulthood (24 years. We determine patterns of change in depression and anxiety using the Child Manifest Anxiety Scale-Revised (CMAS-R and Short Moods and Feelings Questionnaire (SMFQ. In addition to examining associations with gender, verbal and nonverbal skills, we use a time-varying variable to investigate relationships between depression and anxiety symptoms and transitions in educational/employment circumstances. The results show that anxiety was higher in participants with LI than age matched peers and remained so from adolescence to adulthood. Individuals with LI had higher levels of depression symptoms than did AMPs at 16 years. Levels in those with LI decreased post-compulsory schooling but rose again by 24 years of age. Those who left compulsory school provision (regardless of school type for more choice-driven college but who were not in full-time employment or study by 24 years of age were more likely to show this depression pathway. Verbal and nonverbal skills were not predictive of this pattern of depression over time. The typical female vulnerability for depression and anxiety was observed for AMPs but not for individuals with LI. These findings have implications for service provision, career/employment advice and support for individuals with a history of LI during different transitions from adolescence to adulthood.

Coming of age in Roman Britain: Osteological evidence for pubertal timing.

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Arthur, Nichola A; Gowland, Rebecca L; Redfern, Rebecca C

2016-04-01

Puberty is a key transitional phase of the human life course, with important biological and social connotations. Novel methods for the identification of the pubertal growth spurt and menarche in skeletal remains have recently been proposed (Shapland and Lewis, 2013, 2014). In this study we applied the methods to two Romano-British cemetery samples (1st-early 5th centuries AD) in order to investigate the timing of puberty during this period and further assess the veracity of the methods. Shapland and Lewis' methods (2013, 2014) were applied to 38 adolescents (aged 8-20 years) from the British cemetery sites of Roman London (1st-early 5th centuries AD) and Queenford Farm, Oxfordshire (4th-early 5th centuries AD). Overall, the Romano-British males and females experienced the onset of puberty at similar ages to modern European adolescents, but subsequently experienced a longer period of pubertal development. Menarche occurred between the ages of 15 and 17 years for these Romano-British females, around 2 to 4 years later than for present-day European females. The observed Romano-British pattern of pubertal timing has various possible explanations, including exposure to environmental stressors in early urban environments. The pattern of pubertal timing is largely congruent with social age transitions alluded to in ancient texts and funerary evidence for this period. While there are limitations to the application of these techniques to archaeological samples, they were successfully applied in this study, and may have important implications for understandings of past life courses, as well as providing a long-term perspective on pubertal timing and biocultural interactions. © 2016 Wiley Periodicals, Inc.

Effect of AGE and Sex on thyroid hormone levels in normal egyptian individuals using RIA technique

International Nuclear Information System (INIS)

Abdel-Aziz, S.M.; El-Seify, S.; Megahed, Y.M.; El-Arab, A.

1993-01-01

This work aims to estimate total serum levels of thyroid hormones, namely triiodothyronine (T 3 ) and thyroxine (T 4 ) as well as the pituitary thyrotropin (TSH) in different categories of normal egyptian individuals classified according to age and sex. Radioimmunoassay (RIA) and immunoradiometritassay (IRMA) techniques were used. Results of this study indicate that T 3 and T 4 concentrations decreased significantly with advancing age. This decrement was statistically significant in both sexes and could be attributed to the decline in TBG concentration in the elderly. TSH level was not influenced by sex, however, a slight decrease was observed in the elderly perhaps due to decreased TSH receptors and or cyclic AMP activity. 3 figs., 2 tabs

‘Inconvenient biology:’ advantages and disadvantages of first-time parenting after age 40 using in vitro fertilization

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Mac Dougall, K.; Beyene, Y.; Nachtigall, R.D.

2012-01-01

BACKGROUND As ages at first birth have steadily risen in the industrial west over the last several decades, the phenomenon of ‘delayed childbearing’ has come under research scrutiny by demographers, medical specialists and social scientists. In this study, we specifically explore the perceived advantages and disadvantages of postponed conception as well as participants’ retrospective opinions on the ‘optimal age’ for parenting. METHODS To this end, we examined a cohort purposely chosen to epitomize delayed childbearing, i.e. men and women who used IVF to conceive at the very end of their reproductive capability. In-depth qualitative interviews were conducted between 2009 and 2011 with 46 couples and 15 individual self-selected US women and men who had used IVF to conceive their first child when the woman was aged 40 or older at the time of delivery. Although the demographics of this cohort were consistent with others who use IVF in the USA, their median income was 3–4 times higher than that of the average US family, which may bias their largely positive parenting experiences. RESULTS Most women and men believed that childbearing later in life resulted in advantages for themselves and their families. These included having established careers with financial security and career-time flexibility, enhanced emotional preparedness, committed co-parenting relationships and a positive overall family experience. The main disadvantage was the unexpected difficulty in conceiving that culminated in the use of IVF and resulted in a smaller family than desired, although many expressed feeling ‘lucky’ to have children at all. Other disadvantages were lack of energy for parenting, less available lifetime to spend with children and anticipated stigma as older parents. CONCLUSIONS These disadvantages appear to have influenced conception and parenting experiences so that in hindsight the majority of participants identified the optimal age for first-time parenting as 5�

Effects of aging on control of timing and force of finger tapping.

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Sasaki, Hirokazu; Masumoto, Junya; Inui, Nobuyuki

2011-04-01

The present study examined whether the elderly produced a hastened or delayed tap with a negative or positive constant intertap interval error more frequently in self-paced tapping than in the stimulus-synchronized tapping for the 2 N target force at 2 or 4 Hz frequency. The analysis showed that, at both frequencies, the percentage of the delayed tap was larger in the self-paced tapping than in the stimulus-synchronized tapping, whereas the hastened tap showed the opposite result. At the 4 Hz frequency, all age groups had more variable intertap intervals during the self-paced tapping than during the stimulus-synchronized tapping, and the variability of the intertap intervals increased with age. Thus, although the increase in the frequency of delayed taps and variable intertap intervals in the self-paced tapping perhaps resulted from a dysfunction of movement timing in the basal ganglia with age, the decline in timing accuracy was somewhat improved by an auditory cue. The force variability of tapping at 4 Hz further increased with age, indicating an effect of aging on the control of force.

Genetic and environmental sources of individual religiousness: the roles of individual personality traits and perceived environmental religiousness.

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Kandler, Christian; Riemann, Rainer

2013-07-01

In the current study, we examined the genetic and environmental sources of the links between individual religiousness and individual personality traits, perceived parental religiousness, and perceived peer religiousness. Data from 870 individuals (incl. 394 twin pairs) were analyzed. Variance in individual religiousness was significantly influenced by genetic effects, environmental influences shared by twins reared together, and individual-specific environmental influences. Individual religiousness showed significant associations with age, sex, specific personality traits (e.g., agreeableness, openness to values), and perceived religiousness of important social interaction partners, such as parents, best friends, and spouses. The links to personality traits were relatively small and primarily genetically mediated. The associations between individual religiousness and parental religiousness were substantial and mediated by shared environmental effects. These links significantly decreased across age accompanying a significant decrease of shared environmental influences on individual religiousness. The correlations between individual religiousness and perceived religiousness of spouses and best friends were relatively moderate but increased with age. These associations were mediated by genetic as well as nonshared environmental sources accompanying an increase of nonshared environmental influences on individual religiousness with age. The results suggest that inter-individual differences in religiousness are due to multiple sources.

Aging on a different scale--chronological versus pathology-related aging.

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Melis, Joost P M; Jonker, Martijs J; Vijg, Jan; Hoeijmakers, Jan H J; Breit, Timo M; van Steeg, Harry

2013-10-01

In the next decades the elderly population will increase dramatically, demanding appropriate solutions in health care and aging research focusing on healthy aging to prevent high burdens and costs in health care. For this, research targeting tissue-specific and individual aging is paramount to make the necessary progression in aging research. In a recently published study we have attempted to make a step interpreting aging data on chronological as well as pathological scale. For this, we sampled five major tissues at regular time intervals during the entire C57BL/6J murine lifespan from a controlled in vivo aging study, measured the whole transcriptome and incorporated temporal as well as physical health aspects into the analyses. In total, we used 18 different age-related pathological parameters and transcriptomic profiles of liver, kidney, spleen, lung and brain and created a database that can now be used for a broad systems biology approach. In our study, we focused on the dynamics of biological processes during chronological aging and the comparison between chronological and pathology-related aging.

Potential for timing high-energy marine inundation events in the recent geological past through age-dating of reef boulders in Fiji

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Terry, James P.; Etienne, Samuel

2014-12-01

Transported coastal boulders have increasingly come to represent a valuable element of investigations within the broader framework of multi-proxy approaches applied to coastal hazard studies. Through a case study on Taveuni Island in Fiji, this paper outlines some approaches and hindrances to effective timing of prehistorical high-energy marine inundation events (storms and tsunamis) on tropical coastlines from the evidence of reef-platform carbonate boulders. Various sources of errors are outlined that investigators must consider when attempting to use carbonate boulder ages as a surrogate for timing past events. On Taveuni, uranium : thorium dates with a high level of precision (1-7 years) suggest that major inundation events have a return period of approximately 40-45 years since 1650 AD. Of particular importance, considerably different age dates are provided by coral samples sourced from the top and bottom (i.e. opposite faces) of individual boulders, so highlighting interpretation biases that must be avoided.

The individual life cycle and economic growth : An essay on demographic macroeconomics

NARCIS (Netherlands)

Heijdra, B.J.; Mierau, J.O.

We develop a demographic macroeconomic model that captures the salient life-cycle features at the individual level and, at the same time, allows us to pinpoint the main mechanisms at play at the aggregate level. At the individual level the model features both age-dependent mortality and productivity

Processing Efficiency in Preschoolers' Memory Span: Individual Differences Related to Age and Anxiety

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Visu-Petra, Laura; Miclea, Mircea; Cheie, Lavinia; Benga, Oana

2009-01-01

In self-paced auditory memory span tasks, the microanalysis of response timing measures represents a developmentally sensitive measure, providing insights into the development of distinct processing rates during recall performance. The current study first examined the effects of age and trait anxiety on span accuracy (effectiveness) and response…

Pattern formation in individual-based systems with time-varying parameters

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Ashcroft, Peter; Galla, Tobias

2013-12-01

We study the patterns generated in finite-time sweeps across symmetry-breaking bifurcations in individual-based models. Similar to the well-known Kibble-Zurek scenario of defect formation, large-scale patterns are generated when model parameters are varied slowly, whereas fast sweeps produce a large number of small domains. The symmetry breaking is triggered by intrinsic noise, originating from the discrete dynamics at the microlevel. Based on a linear-noise approximation, we calculate the characteristic length scale of these patterns. We demonstrate the applicability of this approach in a simple model of opinion dynamics, a model in evolutionary game theory with a time-dependent fitness structure, and a model of cell differentiation. Our theoretical estimates are confirmed in simulations. In further numerical work, we observe a similar phenomenon when the symmetry-breaking bifurcation is triggered by population growth.

Measuring trends in age at first sex and age at marriage in Manicaland, Zimbabwe.

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Cremin, I; Mushati, P; Hallett, T; Mupambireyi, Z; Nyamukapa, C; Garnett, G P; Gregson, S

2009-04-01

To identify reporting biases and to determine the influence of inconsistent reporting on observed trends in the timing of age at first sex and age at marriage. Longitudinal data from three rounds of a population-based cohort in eastern Zimbabwe were analysed. Reports of age at first sex and age at marriage from 6837 individuals attending multiple rounds were classified according to consistency. Survival analysis was used to identify trends in the timing of first sex and marriage. In this population, women initiate sex and enter marriage at younger ages than men but spend much less time between first sex and marriage. Among those surveyed between 1998 and 2005, median ages at first sex and first marriage were 18.5 years and 21.4 years for men and 18.2 years and 18.5 years, respectively, for women aged 15-54 years. High levels of reports of both age at first sex and age at marriage among those attending multiple surveys were found to be unreliable. Excluding reports identified as unreliable from these analyses did not alter the observed trends in either age at first sex or age at marriage. Tracing birth cohorts as they aged revealed reporting biases, particularly among the youngest cohorts. Comparisons by birth cohorts, which span a period of >40 years, indicate that median age at first sex has remained constant over time for women but has declined gradually for men. Although many reports of age at first sex and age at marriage were found to be unreliable, inclusion of such reports did not result in artificial generation or suppression of trends.

A morphometric study of measurements of heart in adults and its relation with age and height of the individual: A post-mortem study

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Chandni Gupta

2014-01-01

Full Text Available Objective: Reconstructive and replacement operations of diseased cardiac valves are commonly practiced these days. It may be noted that the choice of proper reconstructive intervention and prosthetic replacement might require the normal morphometric measurements of heart in relation with general body parameters, like age and height. So, this study was undertaken to measure various measurements of heart and its relation with age and height of the individual. Materials and Methods: Sixty five normal post-mortem hearts of adults were taken from the mortuary of Department of Forensic Medicine. Age of the individual was noted. Length of the deceased was measured with a measuring tape from the level of vertex to the outer border of heel. Length (from apex to base, breadth (at broadest diameter and thickness of the heart were measured with slide callipers. Weight was measured with weighing machine. Results: The mean length, breadth, thickness of heart in males and females are 11.25, 8.78, 3.97 cm and 10.60, 8.31, 3.63 cm. The mean weight of heart in males and females was 323 and 276 gms. There was significant correlation with weight of individual and weight of heart in males. There was significant correlation with age of individual and length of heart in females. Conclusion: This study will be helpful for cardiothoracic surgeons while doing surgery on hearts.

Circadian rhythms, time-restricted feeding, and healthy aging.

Science.gov (United States)

Manoogian, Emily N C; Panda, Satchidananda

2017-10-01

Circadian rhythms optimize physiology and health by temporally coordinating cellular function, tissue function, and behavior. These endogenous rhythms dampen with age and thus compromise temporal coordination. Feeding-fasting patterns are an external cue that profoundly influence the robustness of daily biological rhythms. Erratic eating patterns can disrupt the temporal coordination of metabolism and physiology leading to chronic diseases that are also characteristic of aging. However, sustaining a robust feeding-fasting cycle, even without altering nutrition quality or quantity, can prevent or reverse these chronic diseases in experimental models. In humans, epidemiological studies have shown erratic eating patterns increase the risk of disease, whereas sustained feeding-fasting cycles, or prolonged overnight fasting, is correlated with protection from breast cancer. Therefore, optimizing the timing of external cues with defined eating patterns can sustain a robust circadian clock, which may prevent disease and improve prognosis. Copyright © 2016 Elsevier B.V. All rights reserved.

Introducing a Third Timed Up & Go Test Trial Improves Performances of Hospitalized and Community-Dwelling Older Individuals

DEFF Research Database (Denmark)

Bloch, Mette Linding; R. Jønsson, Line R. Jønsson; T. Kristensen, Morten

2017-01-01

in hospitalized and community-dwelling older individuals. Methods: Eighty-two participants (50 from a geriatric hospital unit and 32 from an outpatient geriatric center; 52 women, 30 men) with a mean (SD) age of 83.6 (7.9) years were included in this cross-sectional study. All participants (except one from...... the hospital unit) performed 3 TUG trials, as fast as safely possible on the same day, and separated by up to 1-minute pauses. A rollator (4-wheeled rolling walker) was used as a standardized walking aid in the geriatric hospital unit, whereas participants used their normal walking aid (if any......) in the outpatient geriatric center. Results and Discussion: The fastest trial was trial 3 for 47 (57%), trial 2 for 25 (31%), and trial 1 for 10 (12%). Repeated-measures analyses of variance with Bonferroni corrections showed that TUG times improved from trial 1 to trial 3 (P

Evaluating methods for estimating space-time paths of individuals in calculating long-term personal exposure to air pollution

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Schmitz, Oliver; Soenario, Ivan; Vaartjes, Ilonca; Strak, Maciek; Hoek, Gerard; Brunekreef, Bert; Dijst, Martin; Karssenberg, Derek

2016-04-01

Air pollution is one of the major concerns for human health. Associations between air pollution and health are often calculated using long-term (i.e. years to decades) information on personal exposure for each individual in a cohort. Personal exposure is the air pollution aggregated along the space-time path visited by an individual. As air pollution may vary considerably in space and time, for instance due to motorised traffic, the estimation of the spatio-temporal location of a persons' space-time path is important to identify the personal exposure. However, long term exposure is mostly calculated using the air pollution concentration at the x, y location of someone's home which does not consider that individuals are mobile (commuting, recreation, relocation). This assumption is often made as it is a major challenge to estimate space-time paths for all individuals in large cohorts, mostly because limited information on mobility of individuals is available. We address this issue by evaluating multiple approaches for the calculation of space-time paths, thereby estimating the personal exposure along these space-time paths with hyper resolution air pollution maps at national scale. This allows us to evaluate the effect of the space-time path and resulting personal exposure. Air pollution (e.g. NO2, PM10) was mapped for the entire Netherlands at a resolution of 5×5 m2 using the land use regression models developed in the European Study of Cohorts for Air Pollution Effects (ESCAPE, http://escapeproject.eu/) and the open source software PCRaster (http://www.pcraster.eu). The models use predictor variables like population density, land use, and traffic related data sets, and are able to model spatial variation and within-city variability of annual average concentration values. We approximated space-time paths for all individuals in a cohort using various aggregations, including those representing space-time paths as the outline of a persons' home or associated parcel

Variations in relative age effects in individual sports: skiing, figure skating and gymnastics.

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Baker, Joseph; Janning, Christina; Wong, Harmonie; Cobley, Stephen; Schorer, Jörg

2014-01-01

In many sports, policy-makers and administrators employ annual cohorts to reduce differences between athletes during childhood and youth. Although well-intended, unintended relative age effects (RAEs) usually occur. RAEs refer to the specific selection, participation and attainment disadvantages associated with participants' birthdates relative to an arbitrary 'cutoff' date used to group participants within annual age groups. To date, we have little understanding of RAEs in individual sports. In this article, Study 1 considered the presence of RAEs in 1474 ski jumping, 7501 cross-country skiing, 15,565 alpine skiing, 4179 snowboarders and 713 Nordic combined athletes. Chi-square analyses revealed significant RAEs for most of these contexts across sexes. In Study 2, RAEs in the aesthetic sports of figure skating (n=502) and female gymnastics (n=612) were considered. There was no effect for the figure skaters and an atypical effect for the gymnasts. The significant effects across most ski sports coupled with the null effects in figure skating and atypical effect in gymnastics suggest that sport-specific contextual factors are important elements in understanding the mechanisms of RAEs, although further work is necessary to validate these findings.

Dividing time: concurrent timing of auditory and visual events by young and elderly adults.

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McAuley, J Devin; Miller, Jonathan P; Wang, Mo; Pang, Kevin C H

2010-07-01

This article examines age differences in individual's ability to produce the durations of learned auditory and visual target events either in isolation (focused attention) or concurrently (divided attention). Young adults produced learned target durations equally well in focused and divided attention conditions. Older adults, in contrast, showed an age-related increase in timing variability in divided attention conditions that tended to be more pronounced for visual targets than for auditory targets. Age-related impairments were associated with a decrease in working memory span; moreover, the relationship between working memory and timing performance was largest for visual targets in divided attention conditions.

Individual analyses of Lévy walk in semi-free ranging Tonkean macaques (Macaca tonkeana.

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Cédric Sueur

Full Text Available Animals adapt their movement patterns to their environment in order to maximize their efficiency when searching for food. The Lévy walk and the Brownian walk are two types of random movement found in different species. Studies have shown that these random movements can switch from a Brownian to a Lévy walk according to the size distribution of food patches. However no study to date has analysed how characteristics such as sex, age, dominance or body mass affect the movement patterns of an individual. In this study we used the maximum likelihood method to examine the nature of the distribution of step lengths and waiting times and assessed how these distributions are influenced by the age and the sex of group members in a semi free-ranging group of ten Tonkean macaques. Individuals highly differed in their activity budget and in their movement patterns. We found an effect of age and sex of individuals on the power distribution of their step lengths and of their waiting times. The males and old individuals displayed a higher proportion of longer trajectories than females and young ones. As regards waiting times, females and old individuals displayed higher rates of long stationary periods than males and young individuals. These movement patterns resembling random walks can probably be explained by the animals moving from one location to other known locations. The power distribution of step lengths might be due to a power distribution of food patches in the enclosure while the power distribution of waiting times might be due to the power distribution of the patch sizes.

Variations with time and age of the excess cancer risk among A-bomb survivors

International Nuclear Information System (INIS)

Pierce, D.A.; Vaeth, M.; Preston, D.L.

1990-08-01

This report has two aims: 1) to describe and analyze the age/time patterns of excess cancer risk in the atomic bomb survivor cohort followed up by RERF, and 2) to describe statistical methods which are used in RERF's analyses of data on mortality and morbidity in the cohort. In contrast to previous analyses of the cohort cancer mortality data, substantial use is made of Japanese national cancer rates for the purpose of investigation of the age/time variations in excess risk. This analysis considers mortality from all cancers except leukemia as a group. Primary attention is given to description in terms of the age-specific excess relative risk, but the importance of appropriate descriptions of the absolute excess risk is also emphasized. When models for the excess risk allow variation with age and time, both constant relative and absolute excess risk models provide very similar fits to the data. Previous reports have indicated that for a given age-at-exposure and sex, the excess age-specific relative risk is remarkably constant throughout the current follow-up period. Statistical analysis here indicates that for those less than about 35 years of age at exposure there is no departure from this pattern, beyond ordinary sampling variation. For those over about 35 years of age-at-exposure, there is modest evidence of an increasing trend in the excess relative risk, which could be plausibly attributed to effects related to minimal latent period. Some brief consideration is given to modeling the absolute excess risk as the product of an age-at-exposure and time-since-exposure effect. Interpretation of these results, particularly in regard to projections beyond the current follow-up, is discussed. (author)

A Preliminary Study of Individual Responses to Real-Time Pitch and Formant Perturbations

DEFF Research Database (Denmark)

MacDonald, Ewen; Munhall, Kevin G.

2012-01-01

Previous studies have demonstrated a wide range in individuals’ compensations in response to real-time alterations of the auditory feedback of both pitch and formant frequencies. One potential source of this variability may be individual differences in the relative weighting of auditory and somat...

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

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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…

Individual traits as determinants of time to death under extreme drought in Pinus sylvestris L.

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Garcia-Forner, Núria; Sala, Anna; Biel, Carme; Savé, Robert; Martínez-Vilalta, Jordi

2016-10-01

Plants exhibit a variety of drought responses involving multiple interacting traits and processes, which makes predictions of drought survival challenging. Careful evaluation of responses within species, where individuals share broadly similar drought resistance strategies, can provide insight into the relative importance of different traits and processes. We subjected Pinus sylvestris L. saplings to extreme drought (no watering) leading to death in a greenhouse to (i) determine the relative effect of predisposing factors and responses to drought on survival time, (ii) identify and rank the importance of key predictors of time to death and (iii) compare individual characteristics of dead and surviving trees sampled concurrently. Time until death varied over 3 months among individual trees (from 29 to 147 days). Survival time was best predicted (higher explained variance and impact on the median survival time) by variables related to carbon uptake and carbon/water economy before and during drought. Trees with higher concentrations of monosaccharides before the beginning of the drought treatment and with higher assimilation rates prior to and during the treatment survived longer (median survival time increased 25-70 days), even at the expense of higher water loss. Dead trees exhibited less than half the amount of nonstructural carbohydrates (NSCs) in branches, stem and relative to surviving trees sampled concurrently. Overall, our results indicate that the maintenance of carbon assimilation to prevent acute depletion of NSC content above some critical level appears to be the main factor explaining survival time of P. sylvestris trees under extreme drought. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Does presence of metabolic syndrome impact anxiety and depressive disorder screening results in middle aged and elderly individuals? A population based study.

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Butnoriene, Jurate; Steibliene, Vesta; Saudargiene, Ausra; Bunevicius, Adomas

2018-01-08

Depressive and anxiety disorders are common in primary care setting but often remain undiagnosed. Metabolic syndrome (MetS) is also prevalent in the general population and can impair recognition of common mental disorders due to significant co-morbidity and overlap with psychiatric symptoms included in self-reported depression/anxiety screening tools. We investigated if MetS has an impact on the accuracy of current major depressive disorder (MDD) and generalized anxiety disorder (GAD) screening results using the Hospital Anxiety and Depression scale (HADS). A total of 1115 (562 men; mean age 62.0 ± 9.6 years) individuals of 45+ years of age were randomly selected from the general population and evaluated for current MetS; depressive and anxiety symptoms (HADS); and current MDD and GAD (Mini International Neuropsychiatric Interview [MINI]). The MetS was diagnosed in 34.4% of the study participants. Current MDD and GAD were more common in individuals with MetS relative to individuals without MetS (25.3% vs 14.2%, respectively, p Depression subscale for current MDE were ≥9 in individuals with MetS (sensitivity = 87%, specificity = 73% and PPV = 52%) and ≥8 in individuals without MetS (sensitivity = 81%, specificity = 78% and PPV = 38%). At threshold of ≥9 the HADS-Anxiety subscale demonstrated optimal psychometric properties for current GAD screening in individuals with MetS (sensitivity = 91%, specificity = 85% and PPV = 72%) and without MetS (sensitivity = 84%, specificity = 83% and PPV = 56%). The HADS is a reliable screening tool for current MDE and GAD in middle aged and elderly population with and without MetS. Optimal thresholds of the HADS-Depression subscale for current MDD is ≥9 for individuals with MetS and ≥8 - without MetS. Optimal threshold of the HADS-Anxiety subscale is ≥9 for current GAD in individuals with and without MetS. The presence of MetS should be considered when interpreting

Sex, Age, and Individual Differences in Bottlenose Dolphins (Tursiops truncatus in Response to Environmental Enrichment

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Holli C. Eskelinen

2015-08-01

Full Text Available Application of environmental enrichment, as a means to successfully decrease undesired behaviors (e.g., stereotypic and improve animal welfare, has been documented in a variety of zoological species. However, a dearth of empirical evidence exists concerning age, sex, and individual differences in response to various types of enrichment tools and activities in Atlantic bottlenose dolphins (Tursiops truncatus. This study involved a comparative assessment of enrichment participation of three resident, bottlenose dolphin populations, over the course of 17 months, with respect to sex and age class (calf, sub-adult, adult. Enrichment sessions were randomly assigned, conducted, and categorically assessed based on participation during seven, broad based enrichment classes (Object, Ingestible, Human, or a combination of the three. Overall, the proportion of participation in enrichment sessions was high (≥ 0.74, with individual differences in participation noted among the three populations. Sessions involving Humans and/or Ingestible items resulted in a significantly higher mean proportion of participation. Sub-adult and adult males were significantly more likely to participate in enrichment sessions, as well as engage in Human Interaction/Object sessions. Calves participated significantly more than adults or sub-adults across all enrichment classes with no noted differences between males and females. These data can serve as a tool to better understand the intricacies of bottlenose dolphin responses to enrichment in an effort to develop strategic enrichment plans with the goal of improving animal well-being and welfare.

Use of non-antiretroviral drugs among individuals with and without HIV-infection

DEFF Research Database (Denmark)

Rasmussen, Line D; Kronborg, Gitte; Larsen, Carsten S

2017-01-01

AIM: We investigated the use of non-antiretroviral drugs in the HIV-infected compared to the general population. METHODS: From the Danish HIV Cohort Study, we identified all HIV-infected individuals older than 18 years at HIV diagnosis who received care in Denmark through 1995-2013 and reported...... no injection drug abuse or hepatitis C infection. Population controls were identified from The Danish Civil Registration System and matched on age and gender (5:1). We analyzed the proportion of individuals who redeemed 0-1, 2-4, 5-9, or 10 or more non-antiretroviral drugs. Data were analyzed according...... to calendar time, age, time from initiation of combination antiretroviral therapy (cART) and stratified by gender, geographical origin and route of HIV transmission. We further analyzed the use of the 25 most used non-antiretroviral drug classes. RESULTS: We identified 4,928 HIV-infected individuals (median...

Age and gender differences in time to collision at braking from the 100-Car Naturalistic Driving Study.

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Montgomery, Jade; Kusano, Kristofer D; Gabler, Hampton C

2014-01-01

Forward collision warning (FCW) is an active safety system that aims to mitigate the effect of forward collisions by warning the driver of objects in front of the vehicle. Success of FCW relies on how drivers react to the alerts. Drivers who receive too many warnings that they deem as unnecessary-that is, nuisance alarms-may grow to distrust and turn the system off. To reduce the perception of nuisance alarms, FCW systems can be tailored to individual driving styles, but these driving styles must first be characterized. The objective of this study was to characterize differences in braking behavior between age and gender groups in car-following scenarios using data from the 100-Car Naturalistic Driving Study. The data source for this study was the 100-Car Naturalistic Driving Study, which recorded the driving of 108 primary drivers for approximately a year. Braking behavior was characterized in terms of time to collision (TTC) at brake application, a common metric used in the design of warning thresholds of FCW. Because of the large volume of data analyzed, the TTC at which drivers braked during car-following situations was collected via an automated search algorithm. The minimum TTC for each vehicle speed 10 mph increment from 10 mph to 80 mph was recorded for each driver. Mixed model analysis of variance was used to examine the differences between age and gender groups. In total, 527,861 brake applications contained in 11,503 trips were analyzed. Differences in TTC at braking were statistically significant for age and gender (Pbraking of 2.5±0.8 s, and females age 31-50 (n=6) had the highest average minimum TTC at braking of 6.4±0.9 s. On average, women (n=32) braked at a TTC 1.3 s higher than men (n=52). Age was a statistically significant factor for TTC at braking between participants under 30 (n=42) and participants over 30 (n=42), with the latter braking 1.7 s on average before the former. No statistical significance was found between ages 18-20 (n=15) and

“Mobile” Phones: The Time/Space and Society/Individual in the Liquid Modernity

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Arthur Hou-ming Huang

2015-07-01

Full Text Available This paper attempts to understand the impact of mobile phones by taking note of both the technological characteristics of mobile phones and the culture of the liquid modernity. Our contention is that the quality of “instant connectivity” of mobile phones and the “ambivalence” between individual and society beneath the liquid modernity jointly bring about the phenomena which cannot be explicated by “perpetual contact”. These phenomena we attempt to investigate include the softening of time/space frameworks, the blurring of the demarcation between public and private spheres, and the fluidity of the relations between individual and society.

The use of surgery in the treatment of ER+ early stage breast cancer in England: Variation by time, age and patient characteristics.

Science.gov (United States)

Richards, P; Ward, S; Morgan, J; Lagord, C; Reed, M; Collins, K; Wyld, L

2016-04-01

To assess whether the proportion of patients aged 70 and over with ER+ operable breast cancer in England who are treated with surgery has changed since 2002, and to determine whether age and individual level factors including tumour characteristics and co-morbidity influence treatment choice. A retrospective cohort analysis of routinely collected cancer registration data from two English regions (West Midlands, Northern & Yorkshire) was carried out (n = 17,129). Trends in surgical use over time for different age groups were assessed graphically and with linear regression. Uni- and multivariable logistic regressions were used to assess the effects of age, comorbidity, deprivation and disease characteristics on treatment choice. Missing data was handled using multiple imputation. There is no evidence of a change in the proportion of patients treated surgically over time. The multivariable model shows that age remains an important predictor of whether or not a woman with ER+ operable breast cancer receives surgery after covariate adjustment (Odds ratio of surgery vs no surgery, 0.82 (per year over 70)). Co-morbidity, deprivation, symptomatic presentation, later stage at diagnosis and low grade are also associated with increased probability of non-surgical treatment. Contrary to current NICE guidance in England, age appears to be an important factor in the decision to treat operable ER+ breast cancer non-surgically. Further research is needed to assess the role of other age-related factors on treatment choice, and the effect that current practice has on survival and mortality from breast cancer for older women. Copyright © 2016 Elsevier Ltd. All rights reserved.

Does part-time sick leave help individuals with mental disorders recover lost work capacity?

Science.gov (United States)

Andrén, Daniela

2014-06-01

This paper aims to answer the question whether combining sick leave with some hours of work can help employees diagnosed with a mental disorder (MD) increase their probability of returning to work. Given the available data, this paper analyzes the impact of part-time sick leave (PTSL) on the probability of fully recovering lost work capacity for employees diagnosed with an MD. The effects of PTSL on the probability of fully recovering lost work capacity are estimated by a discrete choice one-factor model using data on a nationally representative sample extracted from the register of the National Agency of Social Insurance in Sweden and supplemented with information from questionnaires. All individuals in the sample were 20-64 years old and started a sickness spell of at least 15 days between 1 and 16 February 2001. We selected all employed individuals diagnosed with an MD, with a final sample of 629 individuals. The results show that PTSL is associated with a low likelihood of full recovery, yet the timing of the assignment is important. PTSL's effect is relatively low (0.015) when it is assigned in the beginning of the spell but relatively high (0.387), and statistically significant, when assigned after 60 days of full-time sick leave (FTSL). This suggests efficiency improvements from assigning employees with an MD diagnosis, when possible, to PTSL. The employment gains will be enhanced if employees with an MD diagnosis are encouraged to return to work part-time after 60 days or more of FTSL.

Barriers to Leisure-Time Physical Activities in Individuals with Spinal Cord Injury.

Science.gov (United States)

Hwang, Eric J; Groves, Mary D; Sanchez, Jacqueline N; Hudson, Cassandra E; Jao, Rachel G; Kroll, Meghan E

2016-07-01

This study investigated the personal, environmental, and activity barriers to leisure-time physical activities (LTPAs) among individuals with spinal cord injury (SCI). A survey instrument was administered to 85 participants with SCI. Personal barriers to LTPAs included issues involving motivation, pain, scheduling, and financial resources. Environmental barriers marked the issues regarding availability and accessibility to specialized programs, activities, and professional services. Activity barriers included limitations in equipment, training, and personal skills required by the selected activities. Significant negative correlations were found between these barriers and the levels of physical activity and satisfaction with physical activity. While working with clients with SCI, occupational therapists should identify those LTPA barriers and possible solutions in order to establish individualized action plans for enhancing participation in LTPAs.

Palaeodemographic and palaeopathological characteristics of individuals buried in three Bronze Age sites from southern Croatia

Directory of Open Access Journals (Sweden)

M. Novak

2011-12-01

Full Text Available The purpose of this study is to reconstruct paleodemographic and paleopathological characteristics of sixteen individuals (three subadults, seven males and six females buried in three Bronze Age sites (Crip, Matkovići, and Veliki Vanik located in southern Croatia. The analysed sample is characterised by the presence of pathological changes which are often associated with stressful episodes such as anaemia, inadequate nutrition, infectious diseases and the occurrence of parasites. Cribra orbitalia, dental enamel hypoplasia, porotic hyperostosis and periostitis were observed in seven out of sixteen analysed skeletons. One ulnar “parry” fracture and three fractures of the frontal bone strongly suggest the presence of deliberate interpersonal violence within the studied communities. The average life span of the adults, as well as the number and character of the observed pathologies, suggest a relatively poor life quality and harsh living conditions in the studied region during the Bronze Age.

Examining the impact of alternative power measures on individual time use in American and Danish couple households

DEFF Research Database (Denmark)

Datta Gupta, Nabanita; Stratton, Leslie S.

2010-01-01

We exploit time diary data for couple households in Denmark and the United States to examine the impact alternative measures of intrahousehold bargaining power have upon different measures of individual time use. Power measures have traditionally been based on current earnings, but earnings are d...... and significantly associated with `power' than housework time and that education share performs quite well as a measure of power. These results are particularly strong on non-work days and in the United States....... are determined by past/present time use decisions and hence potentially endogenous. More powerful individuals have been hypothesized to spend less time on housework, however, housework time also depends upon relative preferences for home produced goods and relative productivity in home production. Gendered...

Relationships between Static and Dynamic Balance and Anticipation Time, Reaction Time in School Children at the Age of 10-12 Years

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Bozkurt, Sinan; Erkut, Oya; Akkoç, Orkun

2017-01-01

The aim of this study is to investigate the relationship between anticipation time, reaction time and balance characteristics in school children at the age of 10-12 years. 11 males and 12 females, 23 students in total, studying at Istanbul Sancaktepe Ibn-i Sina Elementary School, whose average age was 11.06 years, average height was 142.78 cm and…

Role of aging and hippocampus in Time-Place Learning: link to episodic-like memory?

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Cornelis Kees Mulder

2016-01-01

Full Text Available Introduction: with time-place learning (TPL, animals link an event with the spatial location and the time of day. The what-where-when TPL components make the task putatively episodic-like in nature. Animals use an internal sense of time to master TPL, which is circadian system based. Finding indications for a role of the hippocampus and (early aging-sensitivity in TPL would strengthen the episodic-like memory nature of the paradigm. Methods: previously, we used C57Bl/6 mice for our TPL research. Here, we used CD1 mice which are less hippocampal-driven and age faster compared to C57Bl/6 mice. To demonstrate the low degree of hippocampal-driven performance in CD1 mice, a cross maze was used. The spontaneous alternation test was used to score spatial working memory in CD1 mice at four different age categories (young (3-6 months, middle-aged (7-11 months, aged (12-18 months and old (>19 months. TPL performance of middle-aged and aged CD1 mice was tested in a setup with either two or three time points per day (2-arm or 3-arm TPL task. Immunostainings was applied on brains of young and middle-aged C57Bl/6 mice that had successfully mastered the 3-arm TPL task. Results: in contrast to C57Bl/6 mice, middle-aged and aged CD1 mice were less hippocampus-driven and failed to master the 3-arm TPL task. They could, however, master the 2-arm TPL task primarily via an ordinal (non-circadian timing system. c-Fos, CRY2, vasopressin (AVP, and pCREB were investigated. We found no differences at the level of the suprachiasmatic nucleus (SCN; circadian master clock, whereas CRY2 expression was increased in the hippocampal dentate gyrus. The most pronounced difference between TPL trained and control mice was found in c-Fos expression in the paraventricular thalamic nucleus, a circadian system relay station. Conclusions: These results further indicate a key role of CRY proteins in TPL and confirm the limited role of the SCN in TPL. Based on the poor TPL performance of

Aging Trajectories in Different Body Systems Share Common Environmental Etiology: The Healthy Aging Twin Study (HATS).

Science.gov (United States)

Moayyeri, Alireza; Hart, Deborah J; Snieder, Harold; Hammond, Christopher J; Spector, Timothy D; Steves, Claire J

2016-02-01

Little is known about the extent to which aging trajectories of different body systems share common sources of variance. We here present a large twin study investigating the trajectories of change in five systems: cardiovascular, respiratory, skeletal, morphometric, and metabolic. Longitudinal clinical data were collected on 3,508 female twins in the TwinsUK registry (complete pairs:740 monozygotic (MZ), 986 dizygotic (DZ), mean age at entry 48.9 ± 10.4, range 18-75 years; mean follow-up 10.2 ± 2.8 years, range 4-17.8 years). Panel data on multiple age-related variables were used to estimate biological ages for each individual at each time point, in linear mixed effects models. A weighted average approach was used to combine variables within predefined body system groups. Aging trajectories for each system in each individual were then constructed using linear modeling. Multivariate structural equation modeling of these aging trajectories showed low genetic effects (heritability), ranging from 2% in metabolic aging to 22% in cardiovascular aging. However, we found a significant effect of shared environmental factors on the variations in aging trajectories in cardiovascular (54%), skeletal (34%), morphometric (53%), and metabolic systems (53%). The remainder was due to environmental factors unique to each individual plus error. Multivariate Cholesky decomposition showed that among aging trajectories for various body systems there were significant and substantial correlations between the unique environmental latent factors as well as shared environmental factors. However, there was no evidence for a single common factor for aging. This study, the first of its kind in aging, suggests that diverse organ systems share non-genetic sources of variance for aging trajectories. Confirmatory studies are needed using population-based twin cohorts and alternative methods of handling missing data.

Effects of uncertainty, transmission type, driver age and gender on brake reaction and movement time.

Science.gov (United States)

Warshawsky-Livne, Lora; Shinar, David

2002-01-01

Braking time (BT) is a critical component in safe driving, and various approaches have been applied to minimize it. This study analyzed the components of BT in order to assess the effects of age, gender, vehicle transmission type, and event uncertainty, on its two primary components, perception-reaction time and brake-movement time. Perception-reaction time and brake-movement time were measured at the onset of lights for 72 subjects in a simulator. The six experimental conditions were three levels of uncertainty conditions (none, some, and some + false alarms) and two types of transmission (manual and automatic). The 72 subjects, half male and half female, were further divided into three age groups (mean of 23, 30, and 62 years). Each subject had 10 trials in each of the three levels of uncertainty conditions. Transmission type did not significantly affect either perception-reaction time or brake-movement time. Perception-reaction time increased significantly from 0.32 to 0.42 s (P brake-movement time did not change. Perception-reaction time increased (from 0.35 to 0.43 s) with age but brake-movement time did not change with age. Gender did not affect perception-reaction time but did affect brake-movement time (males 0.19 s vs. females 0.16 s). At 90 km/h, a car travels 0.25 m in 0.01 s. Consequently, even such small effects multiplied by millions of vehicle-kilometers can contribute to significant savings in lives and damages.

A Hard Day’s Knights: Movie Time Travel, the Middle Ages, and a New Millenium

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John Engle

2012-10-01

Full Text Available This article addresses the cinematic treatment of the Middle Ages through an analysis of two recent mass-audience American films, Black Knight and Timeline, both of which feature time travel as a leading plot element. Providing context for this discussion is a brief analysis of other similar films, as well as remarks regarding Twain's Connecticut Yankee, Ruskin's The Stones of Venice, and The Idylls of the King by Tennyson. As in these other works, the films in question use certain popular stereotypes of the Middle Ages—endemic violence, rigid class distinctions, religious fanaticism, spiritual cohesion, etc.—as lens through which to view the contemporary world. In addition to their roles as comic or action entertainment vehicles, Black Knight indirectly addresses American individualism and a cutthroat modern corporate culture, whereas Timeline touches upon millennial anxiety, '90's ethnic cleansing, and the American misadventure in Iraq.

Looking Very Old Age in the Eye: A Nuanced Approach to the Fourth Age in Contemporary Irish Fiction: A Case Study.

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Zamorano Llena, Carmen

2018-04-21

Associations of young-old age with successful aging have contributed to relegating negatively perceived aspects of aging to very old age. This has prompted the formation of the social imaginary of the fourth age. Re-examinations of the fourth age foreground the diversity of aging experiences among the oldest old. In this sense, literature is in a privileged position to contribute individual narratives of aging to this field. The main aim of this article is to analyze Irish writer Jennifer Johnston's later fiction and how particularly two of her later fictional works contribute a nuanced re-examination of the fourth age through the narrativization of individual aging experiences of the oldest old in the contemporary Irish context. The work of sociologists and social theorists on re-examinations of the fourth age functions as the framework to analyze the selected fictional texts. The analysis of the oldest old characters in Truth or Fiction and Naming the Stars shows the contribution of literary texts to rethinking the fourth age as a time characterized by the inextricable combination of gains and losses, with emphasis on the diversity of the aging experiences of the oldest old and on the importance of sociocultural influence on individual aging. Combining longitudinal analyses with case studies, such as the ones suggested by these fictional texts, can provide a more accurate knowledge of the experience of advanced old age and the fourth age.

Individual cell lag time distributions of Cronobacter (Enterobacter sakazakii) and impact of pooling samples on its detection in powdered infant formula.

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Miled, Rabeb Bennour; Guillier, Laurent; Neves, Sandra; Augustin, Jean-Christophe; Colin, Pierre; Besse, Nathalie Gnanou

2011-06-01

Cells of six strains of Cronobacter were subjected to dry stress and stored for 2.5 months at ambient temperature. The individual cell lag time distributions of recovered cells were characterized at 25 °C and 37 °C in non-selective broth. The individual cell lag times were deduced from the times taken by cultures from individual cells to reach an optical density threshold. In parallel, growth curves for each strain at high contamination levels were determined in the same growth conditions. In general, the extreme value type II distribution with a shape parameter fixed to 5 (EVIIb) was the most effective at describing the 12 observed distributions of individual cell lag times. Recently, a model for characterizing individual cell lag time distribution from population growth parameters was developed for other food-borne pathogenic bacteria such as Listeria monocytogenes. We confirmed this model's applicability to Cronobacter by comparing the mean and the standard deviation of individual cell lag times to populational lag times observed with high initial concentration experiments. We also validated the model in realistic conditions by studying growth in powdered infant formula decimally diluted in Buffered Peptone Water, which represents the first enrichment step of the standard detection method for Cronobacter. Individual lag times and the pooling of samples significantly affect detection performances. Copyright © 2010 Elsevier Ltd. All rights reserved.

Wolf (Canis lupus) generation time and proportion of current breeding females by age

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Mech, L. David; Barber-Meyer, Shannon M.; Erb, John

2016-01-01

Information is sparse about aspects of female wolf (Canis lupus) breeding in the wild, including age of first reproduction, mean age of primiparity, generation time, and proportion of each age that breeds in any given year. We studied these subjects in 86 wolves (113 captures) in the Superior National Forest (SNF), Minnesota (MN), during 1972–2013 where wolves were legally protected for most of the period, and in 159 harvested wolves from throughout MN wolf range during 2012–2014. Breeding status of SNF wolves were assessed via nipple measurements, and wolves from throughout MN wolf range, by placental scars. In the SNF, proportions of currently breeding females (those breeding in the year sampled) ranged from 19% at age 2 to 80% at age 5, and from throughout wolf range, from 33% at age 2 to 100% at age 7. Excluding pups and yearlings, only 33% to 36% of SNF females and 58% of females from throughout MN wolf range bred in any given year. Generation time for SNF wolves was 4.3 years and for MN wolf range, 4.7 years. These findings will be useful in modeling wolf population dynamics and in wolf genetic and dog-domestication studies.

Age Estimation in Forensic Sciences

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Alkass, Kanar; Buchholz, Bruce A.; Ohtani, Susumu; Yamamoto, Toshiharu; Druid, Henrik; Spalding, Kirsty L.

2010-01-01

Age determination of unknown human bodies is important in the setting of a crime investigation or a mass disaster because the age at death, birth date, and year of death as well as gender can guide investigators to the correct identity among a large number of possible matches. Traditional morphological methods used by anthropologists to determine age are often imprecise, whereas chemical analysis of tooth dentin, such as aspartic acid racemization, has shown reproducible and more precise results. In this study, we analyzed teeth from Swedish individuals using both aspartic acid racemization and radiocarbon methodologies. The rationale behind using radiocarbon analysis is that aboveground testing of nuclear weapons during the cold war (1955–1963) caused an extreme increase in global levels of carbon-14 (14C), which has been carefully recorded over time. Forty-four teeth from 41 individuals were analyzed using aspartic acid racemization analysis of tooth crown dentin or radiocarbon analysis of enamel, and 10 of these were split and subjected to both radiocarbon and racemization analysis. Combined analysis showed that the two methods correlated well (R2 = 0.66, p Aspartic acid racemization also showed a good precision with an overall absolute error of 5.4 ± 4.2 years. Whereas radiocarbon analysis gives an estimated year of birth, racemization analysis indicates the chronological age of the individual at the time of death. We show how these methods in combination can also assist in the estimation of date of death of an unidentified victim. This strategy can be of significant assistance in forensic casework involving dead victim identification. PMID:19965905

Estimated Glomerular Filtration Rate, Cardiovascular Events and Mortality Across Age Groups Among Individuals Older Than 60 Years in Southern Europe.

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Salvador-González, Betlem; Gil-Terrón, Neus; Cerain-Herrero, M Jesús; Subirana, Isaac; Güell-Miró, Roser; Rodríguez-Latre, Luisa M; Cunillera-Puértolas, Oriol; Elosua, Roberto; Grau, Maria; Vila, Joan; Pascual-Benito, Luisa; Mestre-Ferrer, Jordi; Ramos, Rafel; Baena-Díez, José Miguel; Soler-Vila, Maria; Alonso-Bes, Eva; Ruipérez-Guijarro, Laura; Álvarez-Funes, Virtudes; Freixes-Villaró, Esther; Rodríguez-Pascual, Mercedes; Martínez-Castelao, Alberto

2018-06-01

Individuals with a decreased estimated glomerular filtration rate (eGFR) are at increased risk of all-cause (ACM) and cardiovascular mortality; there is ongoing debate about whether older individuals with eGFR 45 to 59mL/min/1.73 m 2 are also at increased risk. We evaluated the association between eGFR and ACM and cardiovascular events (CVE) in people aged 60 to 74 and ≥ 75 years in a population with a low coronary disease incidence. We conducted a retrospective cohort study by using primary care and hospital electronic records. We included 130 233 individuals aged ≥ 60 years with creatinine measurement between January 1, 2010 and December 31, 2011; eGFR was estimated by using the Chronic Kidney Disease Epidemiology Collaboration creatinine equation. The independent association between eGFR and the risk of ACM and hospital admission due to CVE were determined with Cox and Fine-Gray regressions, respectively. The median was age 70 years, and 56.1% were women; 13.5% had eGFR < 60 (69.7% eGFR 45-59). During a median follow-up of 38.2 months, 6474 participants died and 3746 had a CVE. For ACM and CVE, the HR in older individuals became significant at eGFR < 60. Fully adjusted HR for ACM in the eGFR 45 to 59 category were 1.61; 95%CI, 1.37-1.89 and 1.19; 95%CI, 1.10-1.28 in 60- to 74-year-olds and ≥ 75-year-olds, respectively; for CVE HR were 1.28; 95%CI, 1.08-1.51 and 1.12; 95%CI, 0.99-1.26. In a region with low coronary disease incidence, the risk of death and CVE increased with decreasing eGFR. In ≥ 75-year-olds, the eGFR 45 to 59 category, which had borderline risk for CVE, included many individuals without significant additional risk. Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Between-Individual Variability and Interpretation of Associations between Neurophysiological and Behavioral Measures in Aging Populations: Comment on Salthouse (2011)

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Rabbitt, Patrick

2011-01-01

Salthouse (2011) argued that (a) variance between individuals on cognitive test scores remains constant between 20 and 90 years of age and (b) widely recognized problems of deducing functional relationships from patterns of correlations between measurements become especially severe for neuropsychological indices, especially for gross indices of…

Determinants of time limit at velocity corresponding to VO2max in physically active individuals

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Leonardo Gonçalves Ribeiro

2008-07-01

Full Text Available http://dx.doi.org/10.5007/1980-0037.2008v10n1p69 The objective of the present study was to determine the relationship between time limit (Tlim at VO2Máx velocity (VVO2Máx and the variables VO2Máx, VVO2Máx, running economy (RE, ventilatory threshold (VT, strength test (9-10 maximum repetitions, velocity at maximal anaerobic running test (VMART, vertical jump test and body fat percentage. The sample was composed of 18 male volunteers, aged between 18 and 45 years old, non-athletes, but physically active. The study was carried out during fi ve visits, on non-consecutive days and at approximately the same time each day: visit 1 - signature of informed consent form, medical history, anthropometric assessment, aerobic power test and familiarization with Tlim test; visit 2 - RE test and Tlim test; visit 3 - familiarization with VMART test; visit 4 - familiarization with vertical jump and 9-10 maximum repetition tests and VMART test; visit 5 - vertical jump and 9-10 maximum repetition tests. Low (r = 0.220 to – 0.359 and non-signifi cant correlations (p = 0.281 to 0.935 were observed between Tlim and the selected variables, characterizing the low predictive value of Tlim for the sample studied. Thus, and because of the considerable inter-individual variability in Tlim, no variable was identifi ed that was capable of satisfactorily predicting Tlim.

The optimal timing of stimulation to induce long-lasting positive effects on episodic memory in physiological aging.

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Manenti, Rosa; Sandrini, Marco; Brambilla, Michela; Cotelli, Maria

2016-09-15

Episodic memory displays the largest degree of age-related decline. A noninvasive brain stimulation technique that can be used to modulate memory in physiological aging is transcranial Direct Current Stimulation (tDCS). However, an aspect that has not been adequately investigated in previous studies is the optimal timing of stimulation to induce long-lasting positive effects on episodic memory function. Our previous studies showed episodic memory enhancement in older adults when anodal tDCS was applied over the left lateral prefrontal cortex during encoding or after memory consolidation with or without a contextual reminder. Here we directly compared the two studies to explore which of the tDCS protocols would induce longer-lasting positive effects on episodic memory function in older adults. In addition, we aimed to determine whether subjective memory complaints would be related to the changes in memory performance (forgetting) induced by tDCS, a relevant issue in aging research since individuals with subjective memory complaints seem to be at higher risk of later memory decline. The results showed that anodal tDCS applied after consolidation with a contextual reminder induced longer-lasting positive effects on episodic memory, conceivably through reconsolidation, than anodal tDCS during encoding. Furthermore, we reported, providing new data, a moderate negative correlation between subjective memory complaints and forgetting when anodal tDCS was applied after consolidation with a contextual reminder. This study sheds light on the best-suited timing of stimulation to induce long-lasting positive effects on memory function and might help the clinicians to select the most effective tDCS protocol to prevent memory decline. Copyright © 2016 Elsevier B.V. All rights reserved.

Personality Plasticity After Age 30

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Terracciano, Antonio; Costa, Paul T.; McCrae, Robert R.

2009-01-01

Rank-order consistency of personality traits increases from childhood to age 30. After that, different summaries of the literature predict a plateau at age 30, or at age 50, or a curvilinear peak in consistency at age 50. These predictions were evaluated at group and individual levels using longitudinal data from the Guilford-Zimmerman Temperament Survey and the Revised NEO Personality Inventory over periods of up to 42 years. Consistency declined toward a non-zero asymptote with increasing time-interval. Although some scales showed increasing stability after age 30, the rank-order consistencies of the major dimensions and most facets of the Five-Factor Model were unrelated to age. Ipsative stability, assessed with the California Adult Q-Set, was also unrelated to age. These data strengthen claims of predominant personality stability after age 30. PMID:16861305

Implications for would healing of patient age and time elapsed since burn injury.

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Mountford, E M; Blight, A; Cheshire, I M

1995-01-01

To determine the relationship between growth potential in culture and the age of the patient, skin biopsies were obtained from over 60 patients of varying ages. The relationship between the length of time elapsed since burn injury and growth potential was also examined, using biopsies obtained from patients with burns during their treatment. Keratinocytes were extracted from biopsies and assessed for colony-forming ability by standard methods. Repeated subculture of cells was undertaken to determine the reproductive capacity of cells in vitro. Age had no effect on the colony-forming ability of keratinocytes in primary culture; however age did affect the total number of generations achieved by these cells. The growth potential of keratinocytes from patients with severe burns showed considerable variation according to the amount of time which had elapsed since the injury. This was most apparent around one week post-burn. These results need to be investigated further to understand their clinical implications. The study provides an insight into the influence of age and physiological response on the wound healing process in burn injuries.

Dental age estimation in living individuals using 3.0 T MRI of lower third molars.

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Guo, Yucheng; Olze, Andreas; Ottow, Christian; Schmidt, Sven; Schulz, Ronald; Heindel, Walter; Pfeiffer, Heidi; Vieth, Volker; Schmeling, Andreas

2015-11-01

In order to increase the validity of age estimation in adolescents and young adults when there is no legitimation for X-ray examinations, it seems desirable to be able to assess the mineralization of third molars using X-ray-free imaging procedures. In the present study, the mineralization stages of lower third molars were determined prospectively in 269 male and 248 female individuals aged 12 to 24 years using 3.0 T MRI. The classification system of Demirjian et al. was used to determine the stages. This study presents the minima and maxima, means and standard deviations, median values, and lower and upper quartiles separately for both sexes, for the mineralization stages B-H. Statistically significant sex differences were observed for the mineralization stages C, E, F, and G, and a faster developmental rate was observed for males. It was concluded that magnetic resonance imaging is an X-ray-free alternative to orthopantomography when assessing mineralization of third molars.

Prevalence of cognitive impairment in individuals aged over 65 in an urban area: DERIVA study.

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Rodríguez-Sánchez, Emiliano; Mora-Simón, Sara; Patino-Alonso, María C; García-García, Ricardo; Escribano-Hernández, Alfonso; García-Ortiz, Luis; Perea-Bartolomé, Ma Victoria; Gómez-Marcos, Manuel A

2011-11-17

Few data are available on the prevalence of cognitive impairment (CI) in Spain, and the existing information shows important variations depending on the geographical setting and the methodology employed. The aim of this study was to determine the prevalence of CI in individuals aged over 65 in an urban area, and to analyze its associated risk factors. A descriptive, cross-sectional, home questionnaire-based study; Populational, urban setting. The reference population comprised over-65s living in the city of Salamanca (Spain) in 2009. Randomized sampling stratified according to health district was carried out, and a total of 480 people were selected. In all, 327 patients were interviewed (68.10%), with a mean age of 76.35 years (SD: 7.33). Women accounted for 64.5% of the total. A home health questionnaire was used to obtain the following data: age, sex, educational level, family structure, morbidity and functionality. All participants completed a neuropsychological test battery. The prevalence data were compared with those of the European population, with direct adjustment for age and sex. Diagnoses were divided into three general categories: normal cognitive function, cognitive impairment - no dementia (CIND), and dementia. The prevalence of CI among these over-65s was 19% (14.7% CIND and 4.3% dementia). The age-and sex-adjusted global prevalence of CI was 14.9%. CI increased with age (p < 0.001) and decreased with increasing educational level (p < 0.001). Significant risk factors were found with the multivariate analyses: age (OR = 1.08, 95%CI: 1.03-1.12), anxiety-depression (OR = 3.47, 95%CI: 1.61-7.51) and diabetes (OR = 2.07, 95%CI: 1.02-4.18). In turn, years of education was found to be a protective factor (OR = 0.79, 95%CI: 0.70-0.90). Although CI was more frequent among women and in people living without a partner, these characteristics were not significantly associated with CI risk. The observed raw prevalence of CI was 19% (14.9% after adjusting for age

Predicting Age Using Neuroimaging: Innovative Brain Ageing Biomarkers.

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Cole, James H; Franke, Katja

2017-12-01

The brain changes as we age and these changes are associated with functional deterioration and neurodegenerative disease. It is vital that we better understand individual differences in the brain ageing process; hence, techniques for making individualised predictions of brain ageing have been developed. We present evidence supporting the use of neuroimaging-based 'brain age' as a biomarker of an individual's brain health. Increasingly, research is showing how brain disease or poor physical health negatively impacts brain age. Importantly, recent evidence shows that having an 'older'-appearing brain relates to advanced physiological and cognitive ageing and the risk of mortality. We discuss controversies surrounding brain age and highlight emerging trends such as the use of multimodality neuroimaging and the employment of 'deep learning' methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aging of systems: theoretical investigations on system and components time behaviour

International Nuclear Information System (INIS)

Eid, M.; Coudray, R.

1995-01-01

Being a direct indicator of aging, the systems time-dependent failure rates need to be evaluated using qualified methodologies and starting from basic components time-dependent failure data. Basic component time-dependent failure data are not often available. Components failure data used in the paper are issued from some theoretical considerations rather than from field statistical observations. Four academic cases are presented and their results are discussed. Evaluations result in, very often, systems time-dependent failure rates that require understanding and careful interpretation. Kinetic trends of systems and of components may sometimes be different. (authors). 4 figs., 3 tabs., 3 refs., 1 appendix

Age-related slowing of response selection and production in a visual choice reaction time task

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David L Woods

2015-04-01

Full Text Available Aging is associated with delayed processing in choice reaction time (CRT tasks, but the processing stages most impacted by aging have not been clearly identified. Here, we analyzed CRT latencies in a computerized serial visual feature-conjunction task. Participants responded to a target letter (probability 40% by pressing one mouse button, and responded to distractor letters differing either in color, shape, or both features from the target (probabilities 20% each, by pressing the other mouse button. Stimuli were presented randomly to the left and right visual fields and stimulus onset asynchronies (SOAs were adaptively reduced following correct responses using a staircase procedure. In Experiment 1, we tested 1466 participants who ranged in age from 18 to 65 years. CRT latencies increased significantly with age (r = 0.47, 2.80 ms/year. Central processing time (CPT, isolated by subtracting simple reaction times (obtained in a companion experiment performed on the same day from CRT latencies, accounted for more than 80% of age-related CRT slowing, with most of the remaining increase in latency due to slowed motor responses. Participants were faster and more accurate when the stimulus location was spatially compatible with the mouse button used for responding, and this effect increased slightly with age. Participants took longer to respond to distractors with target color or shape than to distractors with no target features. However, the additional time needed to discriminate the more target-like distractors did not increase with age. In Experiment 2, we replicated the findings of Experiment 1 in a second population of 178 participants (ages 18-82 years. CRT latencies did not differ significantly in the two experiments, and similar effects of age, distractor similarity, and stimulus-response spatial compatibility were found. The results suggest that the age-related slowing in visual CRT latencies is largely due to delays in response selection and

Age-related skeletal muscle decline is similar in HIV-infected and uninfected individuals.

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Yarasheski, Kevin E; Scherzer, Rebecca; Kotler, Donald P; Dobs, Adrian S; Tien, Phyllis C; Lewis, Cora E; Kronmal, Richard A; Heymsfield, Steven B; Bacchetti, Peter; Grunfeld, Carl

2011-03-01

Skeletal muscle (SM) mass decreases with advanced age and with disease in HIV infection. It is unknown whether age-related muscle loss is accelerated in the current era of antiretroviral therapy and which factors might contribute to muscle loss among HIV-infected adults. We hypothesized that muscle mass would be lower and decline faster in HIV-infected adults than in similar-aged controls. Whole-body (1)H-magnetic resonance imaging was used to quantify regional and total SM in 399 HIV-infected and 204 control men and women at baseline and 5 years later. Multivariable regression identified associated factors. At baseline and Year 5, total SM was lower in HIV-infected than control men. HIV-infected women were similar to control women at both time points. After adjusting for demographics, lifestyle factors, and total adipose tissue, HIV infection was associated with lower Year 5 SM in men and higher SM in women compared with controls. Average overall 5-year change in total SM was small and age related, but rate of change was similar in HIV-infected and control men and women. CD4 count and efavirenz use in HIV-infected participants were associated with increasing SM, whereas age and stavudine use were associated with decreasing SM. Muscle mass was lower in HIV-infected men compared with controls, whereas HIV-infected women had slightly higher SM than control women after multivariable adjustment. We found evidence against substantially faster SM decline in HIV infected versus similar-aged controls. SM gain was associated with increasing CD4 count, whereas stavudine use may contribute to SM loss.

Timing of the Permian-Triassic biotic crisis: implications from new zircon U/Pb age data (and their limitations)

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Mundil, Roland; Metcalfe, Ian; Ludwig, Kenneth R.; Renne, Paul R.; Oberli, Felix; Nicoll, Robert S.

2001-04-01

The most profound biotic crisis in the Earth's history, causing the near extinction of both terrestrial and marine life, occurred at the end of the Permian period about 253 Myr ago and marks the Paleozoic-Mesozoic era boundary. The cause of this event is still a matter of vigorous debate, with both brief and catastrophic as well as gradual mechanisms having been proposed. Similar to a recent landmark study, this study uses the U-Pb method on zircons from the uppermost Permian/lowermost Triassic ash fall deposits at Meishan (Zhejiang Province, SE China) in order to examine time and rate constraints for these events. The results of both this study and previous work show that for these ash layers, the effects of Pb loss are combined with varying amounts and sources of inheritance, resulting in an age scatter which prohibits the extraction of a statistically robust age in many cases. Though the effects of Pb loss on the zircons analyzed in this study were reduced by leaching the grains in hydrofluoric acid (as opposed to commonly applied air abrasion) prior to analysis, the presence within a single ash layer of multiple generations of older xenocrysts (in many cases only slightly older than the depositional age) has made quantitative interpretation even more difficult. When these combined phenomena bias individual zircon ages by less than a percent, they are extremely difficult to deconvolute, and, if multi-grain analyses are used, can become impossible to recognize (because of the resulting age averaging). Monte Carlo simulations using actual measurements of individual zircon crystals show that age excursions due to Pb loss and xenocrystic contamination for the Meishan bentonites are easily homogenized to the point of undetectability when replicate analyses of multi-grain zircon samples are compared. Thus this study uses only high-precision analyses of single crystals, whether from our work or that of previous studies. Three main conclusions have emerged. First, our

Guarantee of remaining life time. Integrity of mechanical components and control of ageing phenomena

International Nuclear Information System (INIS)

Schuler, X.; Herter, K.H.; Koenig, G.

2012-01-01

The life time of safety relevant systems, structures and components (SSC) of Nuclear Power Plants (NPP) is determined by two main principles. First of all the required quality has to be produced during the design and fabrication process. This means that quality has to be produced and can't be improved by excessive inspections (Basis Safety - quality through production principle). The second one is assigned to the initial quality which has to be maintained during operation. This concerns safe operation during the total life time (life time management), safety against ageing phenomena (AM - ageing management) as well as proof of integrity (e.g. break preclusion or avoidance of fracture for SSC with high safety relevance). Initiated by the Fukushima Dai-ichi event in Japan in spring 2011 for German NPP's Long Term Operation (LTO) is out of question. In June 2011 legislation took decision to phase-out from nuclear by 2022. As a fact safe operation shall be guaranteed for the remaining life time. Within this technical framework the ageing management is a key element. Depending on the safety-relevance of the SSC under observation including preventive maintenance various tasks are required in particular to clarify the mechanisms which contribute systemspecifically to the damage of the components and systems and to define their controlling parameters which have to be monitored and checked. Appropriate continuous or discontinuous measures are to be considered in this connection. The approach to ensure a high standard of quality in operation for the remaining life time and the management of the technical and organizational aspects are demonstrated and explained. The basis for ageing management to be applied to NNPs is included in Nuclear Safety Standard 1403 which describes the ageing management procedures. For SSC with high safety relevance a verification analysis for rupture preclusion (proof of integrity, integrity concept) shall be performed (Nuclear Safety Standard 3206

The Value of Caregiver Time: Costs of Support and Care for Individuals Living with Autism Spectrum Disorder

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Carolyn Dudley

2014-01-01

Full Text Available When a child is diagnosed with autism spectrum disorder, the significance of the impact that diagnosis can have on his or her family’s life is incalculable, except in one respect: cost. If that child is severely impacted and requires constant and lifelong supports, then the value of caregiver time required to support that individual is approximately $5.5 million higher than that for someone without autism. An autism diagnosis of a high-needs child at age two represents the equivalent of telling the family that they must make an immediate lump-sum investment on that day of $1.6 million, invested at a five-per-cent return, to pay for the lifetime costs of care and support their loved one will require. And that amount does not even account for added professional services, such as speech therapists, psychologists, and occupational therapists, or additional out-of-pocket expenses that may be required, such as special equipment or diets. Autism is the most common neurological condition diagnosed in children and it is now estimated that one in 88 children will be diagnosed with autism spectrum disorders. Yet, across Canada, there are significant gaps in the publicly provided support system, leaving the cost burden to be picked up by families. In the case of those individuals requiring constant support, 24 hours a day, every day, the cost of hiring caregivers alone would require an annual income of $200,000 — before a family even begins to pay for shelter, clothing, groceries and other basic necessities. Already families with severe high-needs children are more likely to experience lower income than they might otherwise, due to the extra care commitment their loved one requires. Only a very few families will have the means to afford to pay for total care. So, in most cases, the responsibility for care falls largely, if not entirely, on the family, or in a worst-case scenario, the autistic individual is left with inadequate care. Autism is an

First-Time Sports-Related Concussion Recovery: The Role of Sex, Age, and Sport.

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Neidecker, John M; Gealt, David B; Luksch, John R; Weaver, Martin D

2017-10-01

Concussion is one of the most common injuries in athletes. Current concussion consensus statements propose that female sex may be a modifying factor in concussion management and recovery. To determine whether female athletes in middle school and high school with a first-time, sports-related concussion remained symptomatic longer than their male counterparts. A retrospective medical record analysis was performed among athletes who sustained a concussion between 2011 and 2013. Inclusion criteria consisted of age between 11 and 18 years and diagnosis of first-time concussion sustained while playing organized sports. Using the documented notes in the medical record, length of time that each athlete was symptomatic from his or her concussion was calculated. A total of 110 male and 102 female athletes (N=212) met the eligibility criteria for the study. A significant difference was found in the median number of days female athletes remained symptomatic (28 days) when compared with male athletes (11 days) (Psports played. Female athletes aged 11 to 18 years with first-time, sports-related concussions remained symptomatic for a longer period when compared with male athletes of similar age, regardless of sport played. The mechanism behind this difference needs to be further elucidated.

Time perspective and medication adherence among individuals with hypertension or diabetes mellitus.

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Sansbury, Brittany; Dasgupta, Abhijit; Guthrie, Lori; Ward, Michael

2014-04-01

The study determined if time perspective was associated with medication adherence among people with hypertension and diabetes. Using the Health Beliefs Model, we used path analysis to test direct and indirect effects of time perspective and health beliefs on adherence among 178 people who participated in a community-based survey near Washington, D.C. We measured three time perspectives (future, present fatalistic, and present hedonistic) with the Zimbardo Time Perspective Inventory and medication adherence by self-report. The total model demonstrated a good fit (RMSEA=0.17, 90% CI [0.10, 0.28], p=0.003; comparative fit index=0.91). Future time perspective and age showed direct effects on increased medication adherence; an increase by a single unit in future time perspective was associated with a 0.32 standard deviation increase in reported adherence. There were no significant indirect effects of time perspective with reported medication adherence through health beliefs. The findings provide the first evidence that time perspective plays an under-recognized role as a psychological motivator in medication adherence. Patient counseling for medication adherence may be enhanced if clinicians incorporate consideration of the patient's time perspective. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Social contact patterns of school-age children in Taiwan: comparison of the term time and holiday periods.

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Chen, S-C; You, Z-S

2015-04-01

School closure is one of the most common interventions in the early weeks of an influenza pandemic. Few studies have investigated social contact patterns and compared individual student contact characteristics during the school term and holiday periods in Taiwan. Here, we conducted a well-used questionnaire survey in a junior high school (grades 7-8) in June 2013. All 150 diary-based effective questionnaires covering conversation and skin-to-skin contact behaviour were surveyed. Two questionnaires for each participant were designed to investigate the individual-level difference of contact numbers per day during the two periods. The questionnaire response rate was 44%. The average number of contacts during term time (20·0 contacts per day) and holiday periods (12·6 contacts per day) were significantly different (P holiday periods, the number of contacts decreased by 40%. This study is the first research to investigate the contact numbers and contact characteristics for school-age children during the school term and a holiday period in Taiwan. With regard to public health, this study could provide the basic contact information and database for modelling influenza epidemics for minimizing the spread of influenza that depends on personal contacts for transmission.

Improving Wait Times to Care for Individuals with Multimorbidities and Complex Conditions Using Value Stream Mapping

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Tara Sampalli

2015-07-01

Full Text Available Background Recognizing the significant impact of wait times for care for individuals with complex chronic conditions, we applied a LEAN methodology, namely – an adaptation of Value Stream Mapping (VSM to meet the needs of people with multiple chronic conditions and to improve wait times without additional resources or funding. Methods Over an 18-month time period, staff applied a patient-centric approach that included LEAN methodology of VSM to improve wait times to care. Our framework of evaluation was grounded in the needs and perspectives of patients and individuals waiting to receive care. Patient centric views were obtained through surveys such as Patient Assessment of Chronic Illness Care (PACIC and process engineering based questions. In addition, LEAN methodology, VSM was added to identify non-value added processes contributing to wait times. Results The care team successfully reduced wait times to 2 months in 2014 with no wait times for care anticipated in 2015. Increased patient engagement and satisfaction are also outcomes of this innovative initiative. In addition, successful transformations and implementation have resulted in resource efficiencies without increase in costs. Patients have shown significant improvements in functional health following Integrated Chronic Care Service (ICCS intervention. The methodology will be applied to other chronic disease management areas in Capital Health and the province. Conclusion Wait times to care in the management of multimoribidities and other complex conditions can add a significant burden not only on the affected individuals but also on the healthcare system. In this study, a novel and modified LEAN methodology has been applied to embed the voice of the patient in care delivery processes and to reduce wait times to care in the management of complex chronic conditions.

Aging of nickel added to soils as predicted by soil pH and time.

Science.gov (United States)

Ma, Yibing; Lombi, Enzo; McLaughlin, Mike J; Oliver, Ian W; Nolan, Annette L; Oorts, Koen; Smolders, Erik

2013-08-01

Although aging processes are important in risk assessment for metals in soils, the aging of Ni added to soils has not been studied in detail. In this study, after addition of water soluble Ni to soils, the changes over time in isotopic exchangeability, total concentrations and free Ni(2+) activity in soil pore water, were investigated in 16 European soils incubated outdoors for 18 months. The results showed that after Ni addition, concentrations of Ni in soil pore water and isotopic exchangeability of Ni in soils initially decreased rapidly. This phase was followed by further decreases in the parameters measured but these occurred at slower rates. Increasing soil pH increased the rate and extent of aging reactions. Semi-mechanistic models, based on Ni precipitation/nucleation on soil surfaces and micropore diffusion, were developed and calibrated. The initial fast processes, which were attributed to precipitation/nucleation, occurred over a short time (e.g. 1h), afterwards the slow processes were most likely controlled by micropore diffusion processes. The models were validated by comparing predicted and measured Ni aging in three additional, widely differing soils aged outdoors for periods up to 15 months in different conditions. These models could be used to scale ecotoxicological data generated in short-term studies to longer aging times. Copyright © 2013 Elsevier Ltd. All rights reserved.

Care Preferences Among Middle-Aged and Older Adults With Chronic Disease in Europe: Individual Health Care Needs and National Health Care Infrastructure.

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Mair, Christine A; Quiñones, Ana R; Pasha, Maha A

2016-08-01

The purpose of this study is to expand knowledge of care options for aging populations cross-nationally by examining key individual-level and nation-level predictors of European middle-aged and older adults' preferences for care. Drawing on data from the Survey of Health, Ageing and Retirement in Europe and the Organisation for Economic Co-operation and Development, we analyze old age care preferences of a sample of 6,469 adults aged 50 and older with chronic disease in 14 nations. Using multilevel modeling, we analyze associations between individual-level health care needs and nation-level health care infrastructure and preference for family-based (vs. state-based) personal care. We find that middle-aged and older adults with chronic disease whose health limits their ability to perform paid work, who did not receive personal care from informal sources, and who live in nations with generous long-term care funding are less likely to prefer family-based care and more likely to prefer state-based care. We discuss these findings in light of financial risks in later life and the future role of specialized health support programs, such as long-term care. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Experimental dissociation of individual quality, food and timing of breeding effects on double-brooding in a migratory songbird.

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O'Brien, Erin L; Dawson, Russell D

2013-07-01

Annual reproductive success in many species is influenced by the number of breeding attempts within a season. Although previous studies have shown isolated effects of female quality, food, and timing of breeding on the probability of female birds producing second broods, to our knowledge, none have tested the relative importance of multiple factors and their interactions using simultaneous manipulations within populations of free-living birds. In this study, we show that individual quality and timing of breeding interact to affect the probability of double-brooding in female mountain bluebirds (Sialia currucoides). High-quality females (those that naturally initiated clutches early in the season) were more likely to double-brood, regardless of whether their hatching date was advanced or delayed, whereas later breeding, lower quality females were much less likely to double-brood when their first attempt was delayed. This indicates that annual fecundity of poorer quality (or younger) female bluebirds may be more sensitive to seasonal variation in environmental conditions. In addition, birds that were provided with supplemental food throughout first breeding attempts were more likely to double-brood in one of the study years, suggesting that female bluebirds may be energetically limited in their capacity to initiate a second brood. Females that had their first brood delayed also had a shorter inter-brood interval and were moulting fewer feathers during second broods compared to controls, while females in better condition showed more advanced moult in second breeding attempts. Taken together, our results demonstrate the combined effects of age- or individual quality-mediated energetic trade-offs between current and future reproduction, and between investments in offspring and self-maintenance, on annual fecundity of female birds.

Aging in culture.

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Fung, Helene H

2013-06-01

This article reviews the empirical studies that test socioemotional aging across cultures. The review focuses on comparisons between Western (mostly North Americans and Germans) and Eastern cultures (mostly Chinese) in areas including age-related personality, social relationships, and cognition. Based on the review, I argue that aging is a meaning-making process. Individuals from each cultural context internalize cultural values with age. These internalized cultural values become goals that guide adult development. When individuals from different cultures each pursue their own goals with age, cultural differences in socioemotional aging occur.

What Does Successful Aging Mean? Lay Perception of Successful Aging Among Elderly Singaporeans.

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Feng, Qiushi; Straughan, Paulin Tay

2017-03-01

We explore the culturally specific meaning of successful aging in Singapore, an ethnically diverse city-state in Asia. We aim to investigate lay perceptions of successful aging among the elderly individuals in Singapore and further examine variations of these perceptions. We applied a mixed-method research design. Firstly, we conducted qualitative interviews with 49 elderly respondents, generating 12 main subjective components of successful aging. Next, we did a national survey with a sample of 1,540 local residents aged 50 to 69 years, in which respondents were asked to evaluate the importance of each subjective component of successful aging. We used the regression models and latent class analysis to analyze the correlatives of successful aging and to classify the elderly individuals by perception types. Among 12 components of successful aging, those related to self-sufficiency received the highest acknowledgment among the elderly individuals in Singapore. At least half of them simultaneously highlighted independence from family and dependence on family. Malays and Indians in Singapore valued more of the roles of spouse and children in successful aging, as compared with Chinese. The latent class analysis classified four groups of the elderly individuals according to their lay views on successful aging. As compared with the western model of successful aging, the elderly individuals in Singapore perceived successful aging with a strong focus on familism. These lay perceptions also significantly varied among these elderly individuals. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Limit Behavior of a Stochastic Logistic Model with Individual Time-Dependent Rates

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Yilun Shang

2013-01-01

Full Text Available We investigate a variant of the stochastic logistic model that allows individual variation and time-dependent infection and recovery rates. The model is described as a heterogeneous density dependent Markov chain. We show that the process can be approximated by a deterministic process defined by an integral equation as the population size grows.

Rate of lens lesion development and the age of mice at time of irradiation

International Nuclear Information System (INIS)

Gajewski, A.K.; Majewska, K.; Slowikowska, M.G.

1976-01-01

The rate of lens lesion development has been studied in mice irradiated at different age ranging from one day up to one year old mice. The time needed for the first appearance of lens lesion was shortest in groups of mice irradiated at the age of one, two and three days of life, and longest in groups of mice irradiated at the age of 5 days, 1 week and 2 weeks of life. The time needed for the first appearance of lens lesion for mice irradiated between the third week and one year of life was constant. It was longer than for mice irradiated during the first three days of life and shorter than for mice irradiated at 5 up to 14 days of life. In all but one irradiated groups the age at which the first lens lesion occurred differed significantly from the age at which the first senile changes occurred in the lens of control mice. The one exception was the group of mice irradiated at the age of one year. (author)

Ergodicity breaking, ageing, and confinement in generalized diffusion processes with position and time dependent diffusivity

International Nuclear Information System (INIS)

Cherstvy, Andrey G; Metzler, Ralf

2015-01-01

We study generalized anomalous diffusion processes whose diffusion coefficient D(x, t) ∼ D 0 |x| α t β depends on both the position x of the test particle and the process time t. This process thus combines the features of scaled Brownian motion and heterogeneous diffusion parent processes. We compute the ensemble and time averaged mean squared displacements of this generalized diffusion process. The scaling exponent of the ensemble averaged mean squared displacement is shown to be the product of the critical exponents of the parent processes, and describes both subdiffusive and superdiffusive systems. We quantify the amplitude fluctuations of the time averaged mean squared displacement as function of the length of the time series and the lag time. In particular, we observe a weak ergodicity breaking of this generalized diffusion process: even in the long time limit the ensemble and time averaged mean squared displacements are strictly disparate. When we start to observe this process some time after its initiation we observe distinct features of ageing. We derive a universal ageing factor for the time averaged mean squared displacement containing all information on the ageing time and the measurement time. External confinement is shown to alter the magnitudes and statistics of the ensemble and time averaged mean squared displacements. (paper)

Adjusting the weaning age of calves fed by automated feeders according to individual intakes of solid feed.

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de Passillé, A M; Rushen, J

2012-09-01

When weaned at the ages typical of commercial dairy production, dairy calves usually show reduced growth rates, lowered energy intake, and increased behavioral signs of hunger, reflecting their difficulty in switching from a milk diet to solid feed. However, large differences exist between calves in their ability to adapt to solid feed, and automated feeders allow the age of weaning to be adjusted to an individual calf's intake of solid feed. We examined the effects of weaning according to solid feed intake on age at weaning, feed intake, and behavioral signs of hunger. In a 2×2 factorial design, 60 female Holstein calves in groups of 8 and fed milk, grain starter, and hay from automated feeders began to be weaned when their voluntary intake of grain starter was either 400 g/d (high start) or 200 g/d (low start), with weaning completed when their voluntary intakes of starter were either 1,600 g/d (high end) or 800 g/d (low end). Digestible energy intakes were calculated from milk, starter and hay intakes, corrected for body weights, calves were weighed, and the frequency of visits to the milk feeders were measured each day. The main effects and interactions between treatments were tested with ANOVA. Large differences were observed between calves in the age at which weaning was complete, with weaning completed earlier for low-end calves compared with high-end calves. No treatment effects (either of start amount or end amount) on intakes of milk, starter, or hay or on weight gains occurred. However, the calves that began weaning earlier had longer durations of weaning, greater growth rates from d 20 to 87, and were heavier on d 87, and had lower milk intakes, higher starter intakes, higher hay intakes, and a greater digestible energy intake, but showed more unrewarded visits to the milk feeder. Adjusting the age at which individual calves are weaned off milk according to their ability to eat solid feed can reduce the age at which weaning occurs while reducing the

Individual Test Point Fluctuations of Macular Sensitivity in Healthy Eyes and Eyes With Age-Related Macular Degeneration Measured With Microperimetry.

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Barboni, Mirella Telles Salgueiro; Szepessy, Zsuzsanna; Ventura, Dora Fix; Németh, János

2018-04-01

To establish fluctuation limits, it was considered that not only overall macular sensitivity but also fluctuations of individual test points in the macula might have clinical value. Three repeated measurements of microperimetry were performed using the Standard Expert test of Macular Integrity Assessment (MAIA) in healthy subjects ( N = 12, age = 23.8 ± 1.5 years old) and in patients with age-related macular degeneration (AMD) ( N = 11, age = 68.5 ± 7.4 years old). A total of 37 macular points arranged in four concentric rings and in four quadrants were analyzed individually and in groups. The data show low fluctuation of macular sensitivity of individual test points in healthy subjects (average = 1.38 ± 0.28 dB) and AMD patients (average = 2.12 ± 0.60 dB). Lower sensitivity points are more related to higher fluctuation than to the distance from the central point. Fixation stability showed no effect on the sensitivity fluctuation. The 95th percentile of the standard deviations of healthy subjects was, on average, 2.7 dB, ranging from 1.2 to 4 dB, depending on the point tested. Point analysis and regional analysis might be considered prior to evaluating macular sensitivity fluctuation in order to distinguish between normal variation and a clinical change. S tatistical methods were used to compare repeated microperimetry measurements and to establish fluctuation limits of the macular sensitivity. This analysis could add information regarding the integrity of different macular areas and provide new insights into fixation points prior to the biofeedback fixation training.

Real-Time Mass Spectrometry Monitoring of Oak Wood Toasting: Elucidating Aroma Development Relevant to Oak-aged Wine Quality

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Farrell, Ross R.; Wellinger, Marco; Gloess, Alexia N.; Nichols, David S.; Breadmore, Michael C.; Shellie, Robert A.; Yeretzian, Chahan

2015-11-01

We introduce a real-time method to monitor the evolution of oak aromas during the oak toasting process. French and American oak wood boards were toasted in an oven at three different temperatures, while the process-gas was continuously transferred to the inlet of a proton-transfer-reaction time-of-flight mass spectrometer for online monitoring. Oak wood aroma compounds important for their sensory contribution to oak-aged wine were tentatively identified based on soft ionization and molecular mass. The time-intensity profiles revealed toasting process dynamics illustrating in real-time how different compounds evolve from the oak wood during toasting. Sufficient sensitivity was achieved to observe spikes in volatile concentrations related to cracking phenomena on the oak wood surface. The polysaccharide-derived compounds exhibited similar profiles; whilst for lignin-derived compounds eugenol formation differed from that of vanillin and guaiacol at lower toasting temperatures. Significant generation of oak lactone from precursors was evident at 225 oC. Statistical processing of the real-time aroma data showed similarities and differences between individual oak boards and oak wood sourced from the different origins. This study enriches our understanding of the oak toasting process and demonstrates a new analytical approach for research on wood volatiles.

Different Perceptions of Time Passage Among Older People: A Comparative Study in Terms of Age and Gender

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Mohammad Ali Nazari

2016-04-01

Conclusion: Research findings indicate that age affects time perception so that perceived time in the elderly people is shorter than the real physical time. Our findings also showed that if sources pay less attention to the passage of time or the memory capacity declines, the time estimation will be less. Based on cognitive changes in old age, the cognitive abilities of older people were found to decrease with increasing age. As the accurate processing of time intervals relates to memory capacity and attention, the changes in any cognitive process could affect the differences in the perception of time. Probably due to these factors, the reproduction of time in the older people shortens.

Reference data for distal blood pressure in healthy elderly and middle-aged individuals measured with the strain gauge technique. Part II: Distal blood pressure after exercise

DEFF Research Database (Denmark)

Arveschoug, Anne Kirstine; Vammen, Birthe; Yoshinaka, Emmy

2008-01-01

collected in the early 1970s from healthy individuals in the age range 21-26 years. Our aims were to collect new reference data for DBP at ankle level after exercise based on older populations, and to compare between reference data for different age groups to find out whether the normal values are dependent......Objective. Distal blood pressure (DBP) determination after an exercise test is used on suspicion of arterial peripheral vascular disease (apvd). In our department. the average age of these patients is about 60 years. The usual reference values for pressures after exercise were based on data...... on age. Material and methods. DBP after exercise was measured using the strain-gauge technique on individuals in two groups: group I comprising 25 healthy persons aged between 61 and 82 years, and group II 14 healthy persons aged between 45 and 58 years. Strict rules of inclusion were followed. Results...

Stability of leisure participation from school-age to adolescence in individuals with cerebral palsy.

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Majnemer, Annette; Shikako-Thomas, Keiko; Schmitz, Norbert; Shevell, Michael; Lach, Lucy

2015-12-01

With increasing age, youth with disabilities are at risk for decreased participation in leisure activities, a key component for physical and mental health. This prospective study describes changes in leisure participation and leisure preferences from school-age to adolescence in children with cerebral palsy (CP). Participants were recruited at school-age (6-12 years) for a study on participation and reassessed for a second study on adolescents (12-19 years) if >12 years. Thirty-eight children (24 males) with CP who could actively participate in the completion of the Children's Assessment of Participation and Enjoyment (CAPE) and the Preferences for Activities of Children (PAC) comprised the sample. Average time between assessments was 5.0 ± 1.3 years. Most children were ambulatory (32/38 Gross Motor Function Classification System I-II). In addition to the CAPE and PAC, children were evaluated using the Gross Motor Function Measure-66 and parents completed a socio-demographic questionnaire. Paired t-tests revealed a significant decline in leisure participation diversity and intensity (CAPE) for recreation (p.05). Diversity of active-physical activities increased modestly (p=.06) although intensity of participation in this activity domain decreased (p=.003). There was also a decline in enjoyment of leisure activities. Preferences for these leisure activities remained unchanged between school-age and adolescence, except for recreational activities. Gender, maternal education, family income and gross motor ability were not related to differences in CAPE/PAC scores with increasing age. Findings suggest that over time, children with CP's participation in leisure activities diminishes, which is of concern to their functioning and well-being. Parents may be more involved in early childhood in facilitating participation whereas in adolescence, youth may be faced with more environmental barriers and a greater awareness of challenges to participation. Adolescents

Internal Jugular Vein Cross-Sectional Area Enlargement Is Associated with Aging in Healthy Individuals.

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Christopher Magnano

Full Text Available Internal jugular vein (IJV narrowing has been implicated in central nervous system pathologies, however normal physiological age- and gender-related IJV variance in healthy individuals (HIs has not been adequately assessed.We assessed the relationship between IJV cross-sectional area (CSA and aging.This study involved 193 HIs (63 males and 130 females who received 2-dimensional magnetic resonance venography at 3T. The minimum CSA of the IJVs at cervical levels C2/C3, C4, C5/C6, and C7/T1 was obtained using a semi-automated contouring-thresholding technique. Subjects were grouped by decade. Pearson and partial correlation (controlled for cardiovascular risk factors, including hypertension, heart disease, smoking and body mass index and analysis of variance analyses were used, with paired t-tests comparing side differences.Mean right IJV CSA ranges were: in males, 41.6 mm2 (C2/C3 to 82.0 mm2 (C7/T1; in females, 38.0 mm2 (C2/C3 to 62.3 mm2 (C7/T1, while the equivalent left side ranges were: in males, 28.0 mm2 (C2/C3 to 52.2 mm2 (C7/T1; in females, 27.2 mm2 (C2/C3 to 47.8 mm2 (C7/T1. The CSA of the right IJVs was significantly larger (p<0.001 than the left at all cervical levels. Controlling for cardiovascular risk factors, the correlation between age and IJV CSA was more robust in males than in the females for all cervical levels.In HIs age, gender, hand side and cervical location all affect IJV CSA. These findings suggest that any definition of IJV stenosis needs to account for these factors.

Maladaptation of cerebral perfusion in the spinal cord injured individuals

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Cho, Ihn Ho; Chun, Kyung A.; Lee, Hyoung Woo; Ahn, Sang Ho; Hayashida, Kohei [National Cardiovascular Center, Osaka (Korea, Republic of)

2001-07-01

The aim of this study was to evaluate the tilt-induced alteration of cerebral perfusion of spinal cord injured individuals. Supine and upright sitting brain SPECT was performed using a 1-day protocol with {sup 99m}Tc-ethylcysteinate dimer (ECD) in 11 SCI individuals (mean age, 32.6 y), with lesions between C3 and T4, ad 5 AB individuals (mean age, 31.4 y). The patients rested on a wheelchair in the supine position. Then, they sat up and, at the same time 555MBq of ECD was injected. The upright SPECT was done. Finally, 740MBq of ECD was injected and supine SPECT was performed again. The SPECT data were acquired with dual head gamma camera (E-cam, Siemens). For semiquantitative analysis, 14 ROIs were drawn on the brain. In the SCI individuals, the radiotracer uptake in the frontal, temporal and parietal areas were significantly decreased in the upright SPECT. No postural changes was evident in the occipital lobe, basal ganglia and thalamus in the SCI individuals. In the AB individuals, there were no such changes on the upright SPECT. Postural cerebral hypoperfusion in the frontal, temporal and parietal areas in the SCI individuals might relate to maladaptation of the vascular response during the upright position.

Genomic integrity and the ageing brain.

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Chow, Hei-man; Herrup, Karl

2015-11-01

DNA damage is correlated with and may drive the ageing process. Neurons in the brain are postmitotic and are excluded from many forms of DNA repair; therefore, neurons are vulnerable to various neurodegenerative diseases. The challenges facing the field are to understand how and when neuronal DNA damage accumulates, how this loss of genomic integrity might serve as a 'time keeper' of nerve cell ageing and why this process manifests itself as different diseases in different individuals.

Age and ethnic disparities in incidence of stroke over time: the South London Stroke Register.

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Wang, Yanzhong; Rudd, Anthony G; Wolfe, Charles D A

2013-12-01

Data on continuous monitoring of stroke risk among different age and ethnic groups are lacking. We aimed to investigate age and ethnic disparities in stroke incidence over time from an inner-city population-based stroke register. Trends in stroke incidence and before-stroke risk factors were investigated with the South London Stroke Register, a population-based register covering a multiethnic population of 357 308 inhabitants. Age-, ethnicity-, and sex-specific incidence rates with 95% confidence intervals were calculated, assuming a Poisson distribution and their trends over time tested by the Cochran-Armitage test. Four thousand two hundred forty-five patients with first-ever stroke were registered between 1995 and 2010. Total stroke incidence reduced by 39.5% during the 16-year period from 247 to 149.5 per 100 000 population (Pstroke incidence were observed in men, women, white groups, and those aged>45 years, but not in those aged 15 to 44 years (12.6-10.1; P=0.2034) and black groups (310.1-267.5; P=0.3633). The mean age at stroke decreased significantly from 71.7 to 69.6 years (P=0.0001). The reduction in prevalence of before-stroke risk factors was mostly seen in white patients aged>55 years, whereas an increase in diabetes mellitus was observed in younger black patients aged 15 to 54 years. Total stroke incidence decreased during the 16-year time period. However, this was not seen in younger age groups and black groups. The advances in risk factor reduction observed in white groups aged>55 years failed to be transferred to younger age groups and black groups.

Discrepancies between estimated and perceived risk of cancer among individuals with hereditary nonpolyposis colorectal cancer

DEFF Research Database (Denmark)

Domanska, K; Nilbert, Mef; Soller, M

2007-01-01

to individual characteristics. A perceived risk of colorectal cancer above 60% was reported by 22/45 individuals, and only one out of five mutation carriers reported a perceived risk > 80%. Female mutation carriers, individuals below age 50, and individuals who received their oncogenetic counseling within 1......Communicating cancer risk and recommending adequate control programs is central for genetic counseling. Individuals affected by hereditary nonpolyposis colorectal cancer (HNPCC) are at about 80% life-time risk of colorectal cancer and for female carriers 40-60% risk of endometrial cancer and 10...... year prior to the study reported higher, albeit not significantly, perceived risks of colorectal cancer. Higher perceived risks were also reported by individuals who had lost a parent to HNPCC-related cancer at early age, whereas individuals with a personal history of cancer did not report a higher...

Discrepancies between estimated and perceived risk of cancer among individuals with hereditary nonpolyposis colorectal cancer

DEFF Research Database (Denmark)

Domanska, K; Nilbert, Mef; Soller, M

2007-01-01

Communicating cancer risk and recommending adequate control programs is central for genetic counseling. Individuals affected by hereditary nonpolyposis colorectal cancer (HNPCC) are at about 80% life-time risk of colorectal cancer and for female carriers 40-60% risk of endometrial cancer and 10...... to individual characteristics. A perceived risk of colorectal cancer above 60% was reported by 22/45 individuals, and only one out of five mutation carriers reported a perceived risk > 80%. Female mutation carriers, individuals below age 50, and individuals who received their oncogenetic counseling within 1...... year prior to the study reported higher, albeit not significantly, perceived risks of colorectal cancer. Higher perceived risks were also reported by individuals who had lost a parent to HNPCC-related cancer at early age, whereas individuals with a personal history of cancer did not report a higher...

Dance for Individuals With Dementia.

Science.gov (United States)

Lapum, Jennifer L; Bar, Rachel J

2016-03-01

The movement and music associated with dance plays an important role in many individuals' lives and can become imprinted upon the body and mind. Dance is thus closely associated with memory because of these deep connections. Without conscious thought, dance has the potential to be initiated as individuals age. In the current article, the authors share narrative reflections about their experiences with, and the potential of, dance as an intervention for aging populations diagnosed with dementia-related diseases. They draw upon their experiences in working with the aging population and a dance program currently being developed by Canada's National Ballet School and Baycrest Health Sciences for individuals with dementia-related diseases in long-term care. The current article is structured as dialogue between the authors because it mimics dance as a dialogical encounter between movement and music, and/or between individuals. Copyright 2016, SLACK Incorporated.

The impact of oropharynegeal dysphagia on quality of life in individuals with age over 50 years

International Nuclear Information System (INIS)

Bibi, S.; Iqblal, A.; Ayaz, S.B.; Khan, A.A.; Matee, S.

2015-01-01

Objective: To evaluate the demographics of individuals presented with oropharyngeal dysphagia, correlation of different demographic factors with the quality of life (QOL) after validation of the Urdu translation of Swallowing Quality of Life (SWAL-QOL) questionnaire. Methodology: A cross-sectional survey, carried out at the speech and language therapy department of Armed Forces Institute of Rehabilitation Medicine, Rawalpindi from July 2013 to January 2014 enrolling patients > 50 years of age with oropharyngeal dysphagia and scoring them on Urdu translation of SWAL-QOL questionnaire. The reliability of the tool was measured through Cronbach's alpha coefficient. Results: Of 40 patients, majority (60%) were males, married (62.5 %), illiterate (80%) and settling in age group of 51- 61 years. Most of them were from Punjab (30%) and Sindh (30%). The most common primary pathology was stroke (47.5%).The mean SWAL-QOL score was 147±13 (Range: 124 - 176). Most domains of questionnaire had Cronbach's alpha coefficient = 0.7. No variable was found to be significantly affecting SWAL-QOL score. Conclusion: The Urdu-translated version of SWAL-QOL is a valid tool. QOL in Pakistani patients of age > 50 years with oropharyngeal dysphagia is adversely affected, however, it does not depend on age, gender, marital status, education, ethnicity based on provinces or primary pathology for dysphagia. (author)

Comparison Between Individually and Group-Based Insulin Pump Initiation by Time-Driven Activity-Based Costing.

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Ridderstråle, Martin

2017-07-01

Depending on available resources, competencies, and pedagogic preference, initiation of insulin pump therapy can be performed on either an individual or a group basis. Here we compared the two models with respect to resources used. Time-driven activity-based costing (TDABC) was used to compare initiating insulin pump treatment in groups (GT) to individual treatment (IT). Activities and cost drivers were identified, timed, or estimated at location. Medical quality and patient satisfaction were assumed to be noninferior and were not measured. GT was about 30% less time-consuming and 17% less cost driving per patient and activity compared to IT. As a batch driver (16 patients in one group) GT produced an upward jigsaw-shaped accumulative cost curve compared to the incremental increase incurred by IT. Taking the alternate cost for those not attending into account, and realizing the cost of opportunity gained, suggested that GT was cost neutral already when 5 of 16 patients attended, and that a second group could be initiated at no additional cost as the attendance rate reached 15:1. We found TDABC to be effective in comparing treatment alternatives, improving cost control and decision making. Everything else being equal, if the setup is available, our data suggest that initiating insulin pump treatment in groups is far more cost effective than on an individual basis and that TDABC may be used to find the balance point.

Bacteria as a new model system for aging studies: investigations using light microscopy.

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Ackermann, Martin

2008-04-01

Aging-the decline in an individual's condition over time-is at the center of an active research field in medicine and biology. Some very basic questions have, however, remained unresolved, the most fundamental being: do all organisms age? Or are there organisms that would continue to live forever if not killed by external forces? For a long time it was believed that aging only affected organisms such as animals, plants, and fungi. Bacteria, in contrast, were assumed to be potentially immortal and until recently this assertion remained untested. We used phase-contrast microscopy (on an Olympus BX61) to follow individual bacterial cells over many divisions to prove that some bacteria show a distinction between an aging mother cell and a rejuvenated daughter, and that these bacteria thus age. This indicates that aging is a more fundamental property of organisms than was previously assumed. Bacteria can now be used as very simple model system for investigating why and how organisms age.

Aging and Cardiometabolic Risk in European HEMS Pilots: An Assessment of Occupational Old-Age Limits as a Regulatory Risk Management Strategy.

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Bauer, Hans; Nowak, Dennis; Herbig, Britta

2017-12-11

Old-age limits are imposed in some occupations in an effort to ensure public safety. In aviation, the "Age 60 Rule" limits permissible flight operations conducted by pilots aged 60 and over. Using a retrospective cohort design, we assessed this rule's validity by comparing age-related change rates of cardiometabolic incapacitation risk markers in European helicopter emergency medical service (HEMS) pilots near age 60 with those in younger pilots. Specifically, individual clinical, laboratory, and electrocardiogram (ECG)-based risk markers and an overall cardiovascular event risk score were determined from aeromedical examination records of 66 German, Austrian, Polish, and Czech HEMS pilots (average follow-up 8.52 years). Risk marker change rates were assessed using linear mixed models and generalized additive models. Body mass index increases over time were slower in pilots near age 60 compared to younger pilots, and fasting glucose levels increased only in the latter. Whereas the lipid profile remained unchanged in the latter, it improved in the former. An ECG-based arrhythmia risk marker increased in younger pilots, which persisted in the older pilots. Six-month risk of a fatal cardiovascular event (in or out of cockpit) was estimated between 0% and 0.3%. Between 41% and 95% of risk marker variability was due to unexplained time-stable between-person differences. To conclude, the cardiometabolic risk marker profile of HEMS pilots appears to improve over time in pilots near age 60, compared to younger pilots. Given large stable interindividual differences, we recommend individualized risk assessment of HEMS pilots near age 60 instead of general grounding. © 2017 Society for Risk Analysis.

Sex-specific nonlinear associations between serum lipids and different domains of cognitive function in middle to older age individuals.

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Lu, Yanhui; An, Yu; Yu, Huanling; Che, Fengyuan; Zhang, Xiaona; Rong, Hongguo; Xi, Yuandi; Xiao, Rong

2017-08-01

To examine how serum lipids relates to specific cognitive ability domains between the men and women in Chinese middle to older age individuals. A complete lipid panel was obtained from 1444 individuals, ages 50-65, who also underwent a selection of cognitive tests. Participants were 584 men and 860 women from Linyi city, Shandong province. Multiple linear regression analyses examined serum lipids level as quadratic predictors of sex-specific measure of performance in different cognitive domains, which were adjusted for sociodemographic and lifestyle characteristics. In men, a significant quadratic effect of total cholesterol (TC) was identified for Digit Symbol (B = -0.081, P = 0.044) and also quadratic effect of low density lipoprotein-cholesterol (LDL-C) was identified for Trail Making Test B (B = -0.082, P = 0.045). Differently in women, there were significant quadratic associations between high density lipoprotein-cholesterol (HDL-C) and multiple neuropsychological tests. The nonlinear lipid-cognition associations differed between men and women and were specific to certain cognitive domains and might be of potential relevance for prevention and therapy of cognitive decline.

Incidence and timing of cancer in HIV-infected individuals following initiation of combination antiretroviral therapy.

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Yanik, Elizabeth L; Napravnik, Sonia; Cole, Stephen R; Achenbach, Chad J; Gopal, Satish; Olshan, Andrew; Dittmer, Dirk P; Kitahata, Mari M; Mugavero, Michael J; Saag, Michael; Moore, Richard D; Mayer, Kenneth; Mathews, W Christopher; Hunt, Peter W; Rodriguez, Benigno; Eron, Joseph J

2013-09-01

Cancer is an important cause of morbidity and mortality in individuals infected with human immunodeficiency virus (HIV), but patterns of cancer incidence after combination antiretroviral therapy (ART) initiation remain poorly characterized. We evaluated the incidence and timing of cancer diagnoses among patients initiating ART between 1996 and 2011 in a collaboration of 8 US clinical HIV cohorts. Poisson regression was used to estimate incidence rates. Cox regression was used to identify demographic and clinical characteristics associated with cancer incidence after ART initiation. At initiation of first combination ART among 11 485 patients, median year was 2004 (interquartile range [IQR], 2000-2007) and median CD4 count was 202 cells/mm(3) (IQR, 61-338). Incidence rates for Kaposi sarcoma (KS) and lymphomas were highest in the first 6 months after ART initiation (P cancers combined increased from 416 to 615 cases per 100 000 person-years from 1 to 10 years after ART initiation (average 7% increase per year; 95% confidence interval, 2%-13%). Lower CD4 count at ART initiation was associated with greater risk of KS, lymphoma, and human papillomavirus-related cancer. Calendar year of ART initiation was not associated with cancer incidence. KS and lymphoma rates were highest immediately following ART initiation, particularly among patients with low CD4 cell counts, whereas other cancers increased with time on ART, likely reflecting increased cancer risk with aging. Our results underscore recommendations for earlier HIV diagnosis followed by prompt ART initiation along with ongoing aggressive cancer screening and prevention efforts throughout the course of HIV care.

Individual Differences and Time-Sharing Ability: A Critical Review and Analysis.

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1982-03-01

the mythical innkeeper for which it is named. The paradigm involves the following steps: I) The user chooses a factor solution of interest as a "target...A) L L(T) L(C) LL L(A) A ACT ) A(C) Individual Differences and Time-Sharing Abilities Page 41 TABLE 21: LATENT ROOT PARALLEL A’ALYSIS -- DIFFERENCE...753 10 C(A) .350 11 L .711 12 L(T) .399 13 L(C) .650 14 LL .740 15 L(A) .521 16 A .504 17 ACT ) .489 18 A(C) .559 19 A(L) .545 7. FIGURE 1. LATENT

40 CFR 16.4 - Times, places, and requirements for identification of individuals making requests.

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2010-07-01

... identification (e.g., driver's license, employee identification card, social security card, or credit card) to... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Times, places, and requirements for identification of individuals making requests. 16.4 Section 16.4 Protection of Environment ENVIRONMENTAL...

Intrinsic brain connectivity related to age in young and middle aged adults.

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Michelle Hampson

Full Text Available Age-related variations in resting state connectivity of the human brain were examined from young adulthood through middle age. A voxel-based network measure, degree, was used to assess age-related differences in tissue connectivity throughout the brain. Increases in connectivity with age were found in paralimbic cortical and subcortical regions. Decreases in connectivity were found in cortical regions, including visual areas and the default mode network. These findings differ from those of recent developmental studies examining earlier growth trajectories, and are consistent with known changes in cognitive function and emotional processing during mature aging. The results support and extend previous findings that relied on a priori definitions of regions of interest for their analyses. This approach of applying a voxel-based measure to examine the functional connectivity of individual tissue elements over time, without the need for a priori region of interest definitions, provides an important new tool in brain science.

Assessment of the swallowing function in older individuals referred to myocardial revascularization surgery.

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Dantas, Mara de Oliveira Rodrigues Luiz; Auler, José Otávio Costa; Andrade, Claudia Regina Furquim de

2010-01-01

Swallowing evaluation of older individuals with coronary disease referred to heart surgery. To identify the characteristics of the swallowing function in older individuals referred to myocardial revascularization surgery (MR), using an evaluating protocol composed by a water test, cervical auscultation and pulse oximetry. The Assessment Protocol for Dysphagia Risk through a Combined Swallowing test and Vital Signs monitoring was used (PADTC)--measurements of HR and SpO2 (heart rate and oxygen saturation), water swallowing test with 1, 3, 5, 10, 15 e 20 ml, measurement of respiratory rate and cervical auscultation. The electronic stethoscope was used to analyze the number of swallows, response time and swallowing sound classification. In the Research Group (RG) older individuals with heart disease who were referred to MR were included. In the Control Group (CG) healthy older individuals were included. 38 older individuals were evaluated in the RG (mean age 68 years). In the CG, 30 older individuals were evaluated (mean age 70 years). There was a significant difference for the swallowing response time in older individuals with heart disease who presented HR below 60: swallowing response was shorter for 3 ml, 10 ml, 15 ml e 20 ml. HR was lower for individuals with heart disease. No significant difference was found between the groups for the other analyzed parameters. Older individuals with heart disease presented differences in the swallowing function when compared to healthy older individuals. Older individuals with heart disease presented alterations in the temporal coordination between breathing and swallowing, thus indicating risk for dysphagia.

Correlations between tests of aging in Hiroshima subjects: an attempt to define physiologic age

Energy Technology Data Exchange (ETDEWEB)

Hollingsworth, J W; Hashizume, Asaji; Jablon, Seymour

1964-12-01

Nine physiologic functions which change with age were measured in 437 subjects during their regular visits to the Atomic Bomb Casualty Commission clinic in Hiroshima, Japan. This pilot study was undertaken to determine the feasibility of collecting such data in a population sample physiologic age score. Tests conducted consisted of: skin elasticity, systolic blood pressure, vital capacity, hand grip strength, light extinction time, vibrometer, visual activity, audiometry, and serum cholesterol. The study demonstrated that adequate sample data could be obtained, and that statistical treatment could construct a physiologic age for individual subjects. However, the tests were of limited value below age 40, and the validation of the concept of physiologic age requires eventual correlation with mortality. Since the ABCC program includes a highly accurate mortality survey, it is hoped that data on physiologic aging can be collected and eventually related to mortality. 11 references, 3 figures, 6 tables.

Effects of homocysteine lowering with B vitamins on cognitive aging: meta-analysis of 11 trials with cognitive data on 22,000 individuals12345

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Clarke, Robert; Bennett, Derrick; Parish, Sarah; Lewington, Sarah; Skeaff, Murray; Eussen, Simone JPM; Lewerin, Catharina; Stott, David J; Armitage, Jane; Hankey, Graeme J; Lonn, Eva; Spence, J David; Galan, Pilar; de Groot, Lisette C; Halsey, Jim; Dangour, Alan D; Collins, Rory; Grodstein, Francine

2014-01-01

Background: Elevated plasma homocysteine is a risk factor for Alzheimer disease, but the relevance of homocysteine lowering to slow the rate of cognitive aging is uncertain. Objective: The aim was to assess the effects of treatment with B vitamins compared with placebo, when administered for several years, on composite domains of cognitive function, global cognitive function, and cognitive aging. Design: A meta-analysis was conducted by using data combined from 11 large trials in 22,000 participants. Domain-based z scores (for memory, speed, and executive function and a domain-composite score for global cognitive function) were available before and after treatment (mean duration: 2.3 y) in the 4 cognitive-domain trials (1340 individuals); Mini-Mental State Examination (MMSE)–type tests were available at the end of treatment (mean duration: 5 y) in the 7 global cognition trials (20,431 individuals). Results: The domain-composite and MMSE-type global cognitive function z scores both decreased with age (mean ± SE: −0.054 ± 0.004 and −0.036 ± 0.001/y, respectively). Allocation to B vitamins lowered homocysteine concentrations by 28% in the cognitive-domain trials but had no significant effects on the z score differences from baseline for individual domains or for global cognitive function (z score difference: 0.00; 95% CI: −0.05, 0.06). Likewise, allocation to B vitamins lowered homocysteine by 26% in the global cognition trials but also had no significant effect on end-treatment MMSE-type global cognitive function (z score difference: −0.01; 95% CI: −0.03, 0.02). Overall, the effect of a 25% reduction in homocysteine equated to 0.02 y (95% CI: −0.10, 0.13 y) of cognitive aging per year and excluded reductions of >1 mo per year of treatment. Conclusion: Homocysteine lowering by using B vitamins had no significant effect on individual cognitive domains or global cognitive function or on cognitive aging. PMID:24965307

Age Effects on Cortical Thickness in Cognitively Normal Elderly Individuals

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Sona Hurtz

2014-07-01

Full Text Available Background/Aims: Atrophy in both grey and white matter is found in normal aging. The prefrontal cortex and the frontal lobe white matter are thought to be the most affected regions. Our aim was to examine the effects of normal aging on cortical grey matter using a 3D quantitative cortical mapping method. Methods: We analyzed 1.5-tesla brain magnetic resonance imaging data from 44 cognitively normal elderly subjects using cortical pattern matching and cortical thickness analyses. Linear regression analysis was used to study the effect of age on cortical thickness. 3D map-wide correction for multiple comparisons was conducted with permutation analyses using a threshold of p Results: We found a significant negative association between age and cortical thickness in the right hemisphere (pcorrected = 0.009 and a trend level association in the left hemisphere (pcorrected = 0.081. Age-related changes were greatest in the sensorimotor, bilateral dorsal anterior cingulate and supplementary motor cortices, and the right posterior middle and inferior frontal gyri. Age effects greater in the medial than lateral visual association cortices were also seen bilaterally. Conclusion: Our novel method further validates that normal aging results in diffuse cortical thinning that is most pronounced in the frontal and visual association cortices.

Cochlear nucleus neuron analysis in individuals with presbycusis.

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Hinojosa, Raul; Nelson, Erik G

2011-12-01

The aim of this study was to analyze the cochlear nucleus neuron population in individuals with normal hearing and presbycusis. Retrospective study of archival human temporal bone and brain stem tissues. Using strict inclusion criteria, the temporal bones and cochlear nuclei from six normal hearing individuals and four individuals with presbycusis were selected for analysis. The spiral ganglion cell population, the cochlear nucleus neuron population, and the cell body size of the neurons were quantified in these cases. A relationship was not observed between age and the spiral ganglion cell population in the normal hearing group. Presbycusis subjects exhibited a reduced spiral ganglion cell population. The mean cochlear nucleus neuron population was observed to be significantly higher in the presbycusis group (mean ± standard deviation: 114,170 ± 10,570) compared to the normal hearing group (91,470 ± 9,510) (P = .019). This difference was predominantly the result of greater multipolar and granule cell neuron populations. Only the fusiform neuron type exhibited a significantly different mean cell body cross-sectional area between the normal hearing group (242 ± 27) and the presbycusis group (300 ± 37) (P = .033). This investigation is the first time, to our knowledge, that the populations of the eight neuron types in the cochlear nucleus have been quantified in both normal hearing individuals and individuals with presbycusis. The data support the concept that presbycusis is not an effect of aging alone but instead may be a condition that predisposes one to hearing loss with advancing age and is characterized by a congenitally elevated cochlear nucleus neuron population. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

Effects of Creatine Supplementation on Muscle Strength and Optimal Individual Post-Activation Potentiation Time of the Upper Body in Canoeists

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Chia-Chi Wang

2017-10-01

Full Text Available Creatine supplementation reduces the impact of muscle fatigue on post-activation potentiation (PAP of the lower body, but its effects on the upper body remain unknown. This study examined the effects of creatine supplementation on muscle strength, explosive power, and optimal individual PAP time of the upper body during a set of complex training bouts in canoeists. Seventeen male high school canoeists performed a bench row for one repetition at maximum strength and conducted complex training bouts to determine the optimal individual timing of PAP and distance of overhead medicine ball throw before and after the supplementation. Subjects were assigned to a creatine or placebo group, and later consumed 20 g of creatine or carboxymethyl cellulose per day for six days. After supplementation, the maximal strength in the creatine group significantly increased (p < 0.05. The optimal individual PAP time in the creatine group was significantly earlier than the pre-supplementation times (p < 0.05. There was no significant change in explosive power for either group. Our findings support the notion that creatine supplementation increases maximal strength and shortens the optimal individual PAP time of the upper body in high school athletes, but has no effect on explosive power. Moreover, it was found that the recovery time between a bench row and an overhead medicine ball throw in a complex training bout is an individual phenomenon.

The timing of the shrew: continuous melatonin treatment maintains youthful rhythmic activity in aging Crocidura russula.

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Elodie Magnanou

2009-06-01

Full Text Available Laboratory conditions nullify the extrinsic factors that determine the wild expected lifespan and release the intrinsic or potential lifespan. Thus, wild animals reared in a laboratory often show an increased lifespan, and consequently an increased senescence phase. Senescence is associated with a broad suite of physiological changes, including a decreased responsiveness of the circadian system. The time-keeping hormone melatonin, an important chemical player in this system, is suspected to have an anti-aging role. The Greater White-toothed shrew Crocidura russula is an ideal study model to address questions related to aging and associated changes in biological functions: its lifespan is short and is substantially increased in captivity; daily and seasonal rhythms, while very marked the first year of life, are dramatically altered during the senescence process which starts during the second year. Here we report on an investigation of the effects of melatonin administration on locomotor activity of aging shrews.1 The diel fluctuations of melatonin levels in young, adult and aging shrews were quantified in the pineal gland and plasma. In both, a marked diel rhythm (low diurnal concentration; high nocturnal concentration was present in young animals but then decreased in adults, and, as a result of a loss in the nocturnal production, was absent in old animals. 2 Daily locomotor activity rhythm was monitored in pre-senescent animals that had received either a subcutaneous melatonin implant, an empty implant or no implant at all. In non-implanted and sham-implanted shrews, the rhythm was well marked in adults. A marked degradation in both period and amplitude, however, started after the age of 14-16 months. This pattern was considerably delayed in melatonin-implanted shrews who maintained the daily rhythm for significantly longer.This is the first long term study (>500 days observation of the same individuals that investigates the effects of

What the hyena's laugh tells: Sex, age, dominance and individual signature in the giggling call of Crocuta crocuta

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Weldele Mary

2010-03-01

Full Text Available Abstract Background Among mammals living in social groups, individuals form communication networks where they signal their identity and social status, facilitating social interaction. In spite of its importance for understanding of mammalian societies, the coding of individual-related information in the vocal signals of non-primate mammals has been relatively neglected. The present study focuses on the spotted hyena Crocuta crocuta, a social carnivore known for its complex female-dominated society. We investigate if and how the well-known hyena's laugh, also known as the giggle call, encodes information about the emitter. Results By analyzing acoustic structure in both temporal and frequency domains, we show that the hyena's laugh can encode information about age, individual identity and dominant/subordinate status, providing cues to receivers that could enable assessment of the social position of an emitting individual. Conclusions The range of messages encoded in the hyena's laugh is likely to play a role during social interactions. This call, together with other vocalizations and other sensory channels, should ensure an array of communication signals that support the complex social system of the spotted hyena. Experimental studies are now needed to decipher precisely the communication network of this species.

Size Matters: Individual Variation in Ectotherm Growth and Asymptotic Size

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King, Richard B.

2016-01-01

Body size, and, by extension, growth has impacts on physiology, survival, attainment of sexual maturity, fecundity, generation time, and population dynamics, especially in ectotherm animals that often exhibit extensive growth following attainment of sexual maturity. Frequently, growth is analyzed at the population level, providing useful population mean growth parameters but ignoring individual variation that is also of ecological and evolutionary significance. Our long-term study of Lake Erie Watersnakes, Nerodia sipedon insularum, provides data sufficient for a detailed analysis of population and individual growth. We describe population mean growth separately for males and females based on size of known age individuals (847 captures of 769 males, 748 captures of 684 females) and annual growth increments of individuals of unknown age (1,152 males, 730 females). We characterize individual variation in asymptotic size based on repeated measurements of 69 males and 71 females that were each captured in five to nine different years. The most striking result of our analyses is that asymptotic size varies dramatically among individuals, ranging from 631–820 mm snout-vent length in males and from 835–1125 mm in females. Because female fecundity increases with increasing body size, we explore the impact of individual variation in asymptotic size on lifetime reproductive success using a range of realistic estimates of annual survival. When all females commence reproduction at the same age, lifetime reproductive success is greatest for females with greater asymptotic size regardless of annual survival. But when reproduction is delayed in females with greater asymptotic size, lifetime reproductive success is greatest for females with lower asymptotic size when annual survival is low. Possible causes of individual variation in asymptotic size, including individual- and cohort-specific variation in size at birth and early growth, warrant further investigation. PMID

Size Matters: Individual Variation in Ectotherm Growth and Asymptotic Size.

Directory of Open Access Journals (Sweden)

Richard B King

Full Text Available Body size, and, by extension, growth has impacts on physiology, survival, attainment of sexual maturity, fecundity, generation time, and population dynamics, especially in ectotherm animals that often exhibit extensive growth following attainment of sexual maturity. Frequently, growth is analyzed at the population level, providing useful population mean growth parameters but ignoring individual variation that is also of ecological and evolutionary significance. Our long-term study of Lake Erie Watersnakes, Nerodia sipedon insularum, provides data sufficient for a detailed analysis of population and individual growth. We describe population mean growth separately for males and females based on size of known age individuals (847 captures of 769 males, 748 captures of 684 females and annual growth increments of individuals of unknown age (1,152 males, 730 females. We characterize individual variation in asymptotic size based on repeated measurements of 69 males and 71 females that were each captured in five to nine different years. The most striking result of our analyses is that asymptotic size varies dramatically among individuals, ranging from 631-820 mm snout-vent length in males and from 835-1125 mm in females. Because female fecundity increases with increasing body size, we explore the impact of individual variation in asymptotic size on lifetime reproductive success using a range of realistic estimates of annual survival. When all females commence reproduction at the same age, lifetime reproductive success is greatest for females with greater asymptotic size regardless of annual survival. But when reproduction is delayed in females with greater asymptotic size, lifetime reproductive success is greatest for females with lower asymptotic size when annual survival is low. Possible causes of individual variation in asymptotic size, including individual- and cohort-specific variation in size at birth and early growth, warrant further

Effect of aging time on intergranular corrosion behavior of a newly developed LDX 2404 lean duplex stainless steel

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Zhao, Hui [School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620 (China); Zhang, Ziying, E-mail: zzying@sues.edu.cn [School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620 (China); Zhang, Huizhen [School of Management, University of Shanghai for Science and Technology, Shanghai 200093 (China); Hu, Jun [School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620 (China); Li, Jin [Department of Materials Science, Fudan University, Shanghai 200433 (China)

2016-07-05

The effect of aging at 700 °C for various times on the intergranular corrosion behavior of LDX 2404 duplex stainless steel is investigated by morphological observation and electrochemical detection. Scanning electronic microscopy and transmission electronic microscopy analysis reveal that Cr{sub 2}N, M{sub 23}C{sub 6} and the sigma and chi phases nucleate simultaneously at the initial stages of aging. The granular particles of sigma phase grow larger but fewer with the increase of aging time. The electrochemical detection results show that intergranular corrosion become more severe and the corrosion type evolves from intergranular corrosion into general corrosion as the holding time extends to 48 h. - Highlights: • The IGC behavior of aged LDX 2404 is investigated. • Cr{sub 2}N, M{sub 23}C{sub 6} and the σ and χ phases nucleate simultaneously at the initial stages of aging. • IGC resistance decreases with the increase of aging time. • The corrosion type evolves from IGC into general corrosion for longer aging times.

Philosophy of Aging, Time, and Finitude

NARCIS (Netherlands)

Baars, J.

2010-01-01

Human aging has not drawn much philosophical attention in the past. This is true not only of philosophy but also of other ways of reflecting human life. When the famous theologian Karl Rahner (1980) was in his late seventies, he wondered what theology said about aging. He could conclude only that it

The role of classic risk factors and prothrombotic factor gene mutations in ischemic stroke risk development in young and middle-aged individuals.

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Supanc, Visnja; Sonicki, Zdenko; Vukasovic, Ines; Solter, Vesna V; Zavoreo, Iris; Kes, Vanja B

2014-03-01

In young individuals, a genetically predisposing hypercoagulability and classic modifying risk factors can act synergistically on the ischemic stroke risk development. The aim of the study was to compare the prevalence of classic vascular risk factors and polymorphisms of the G20210A coagulation factor II (prothrombin), Arg506Glu coagulation factor V Leiden, C677T methylenetetrahydrofolate reductase (MTHFR), and 4G/5G plasminogen activator inhibitor-1 (PAI-1) and the impact of these gene mutations and classic vascular risk factors on the overall stroke risk in individuals aged 55 years or younger. The study included 155 stroke patients aged 55 years or younger and 150 control subjects. Stroke prevalence and odds ratio (OR) were assessed for the following parameters: G20210A prothrombin, Arg506Glu factor V Leiden, C677T MTHFR, and 4G/5G PAI-1 polymorphisms; total number of study polymorphisms in a particular subject (genetic sum); and classic vascular risk factors of hypertension, obesity, diabetes mellitus, cigarette smoking, hypercholesterolemia, hypertriglyceridemia, and elevated levels of low-density lipoprotein (LDL) cholesterol and very low-density lipoprotein cholesterol. The prevalence of hypertension (P stroke patients. The following parameters were found to act as independent risk factors for ischemic stroke: decreased HDL cholesterol level (P ischemic stroke in young and middle-aged individuals. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

The Load and Time Dependence of Chemical Bonding-Induced Frictional Ageing of Silica at the Nanoscale

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Tian, K.; Gosvami, N. N.; Goldsby, D. L.; Carpick, R. W.

2015-12-01

Rate and state friction (RSF) laws are empirical relationships that describe the frictional behavior of rocks and other materials in experiments, and reproduce a variety of observed natural behavior when employed in earthquake models. A pervasive observation from rock friction experiments is the linear increase of static friction with the log of contact time, or 'ageing'. Ageing is usually attributed to an increase in real area of contact associated with asperity creep. However, recent atomic force microscopy (AFM) experiments demonstrate that ageing of nanoscale silica-silica contacts is due to progressive formation of interfacial chemical bonds in the absence of plastic deformation, in a manner consistent with the multi-contact ageing behavior of rocks [Li et al., 2011]. To further investigate chemical bonding-induced ageing, we explored the influence of normal load (and thus contact normal stress) and contact time on ageing. Experiments that mimic slide-hold-slide rock friction experiments were conducted in the AFM for contact loads and hold times ranging from 23 to 393 nN and 0.1 to 100 s, respectively, all in humid air (~50% RH) at room temperature. Experiments were conducted by sequentially sliding the AFM tip on the sample at a velocity V of 0.5 μm/s, setting V to zero and holding the tip stationary for a given time, and finally resuming sliding at 0.5 μm/s to yield a peak value of friction followed by a drop to the sliding friction value. Chemical bonding-induced ageing, as measured by the peak friction minus the sliding friction, increases approximately linearly with the product of normal load and the log of the hold time. Theoretical studies of the roles of reaction energy barriers in nanoscale ageing indicate that frictional ageing depends on the total number of reaction sites and the hold time [Liu & Szlufarska, 2012]. We combine chemical kinetics analyses with contact mechanics models to explain our results, and develop a new approach for curve

Mixing times towards demographic equilibrium in insect populations with temperature variable age structures.

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Damos, Petros

2015-08-01

In this study, we use entropy related mixing rate modules to measure the effects of temperature on insect population stability and demographic breakdown. The uncertainty in the age of the mother of a randomly chosen newborn, and how it is moved after a finite act of time steps, is modeled using a stochastic transformation of the Leslie matrix. Age classes are represented as a cycle graph and its transitions towards the stable age distribution are brought forth as an exact Markov chain. The dynamics of divergence, from a non equilibrium state towards equilibrium, are evaluated using the Kolmogorov-Sinai entropy. Moreover, Kullback-Leibler distance is applied as information-theoretic measure to estimate exact mixing times of age transitions probabilities towards equilibrium. Using empirically data, we show that on the initial conditions and simulated projection's trough time, that population entropy can effectively be applied to detect demographic variability towards equilibrium under different temperature conditions. Changes in entropy are correlated with the fluctuations of the insect population decay rates (i.e. demographic stability towards equilibrium). Moreover, shorter mixing times are directly linked to lower entropy rates and vice versa. This may be linked to the properties of the insect model system, which in contrast to warm blooded animals has the ability to greatly change its metabolic and demographic rates. Moreover, population entropy and the related distance measures that are applied, provide a means to measure these rates. The current results and model projections provide clear biological evidence why dynamic population entropy may be useful to measure population stability. Copyright © 2015 Elsevier Inc. All rights reserved.

Uncovering the Dark Energy of Aging.

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Melov, Simon

2016-10-26

A medically relevant understanding of aging requires an appreciation for how time degrades specific, healthy features of individual organisms over the course of their lives. Zach Pincus and colleagues make a key step in this direction, using C. elegans as a model system. Copyright © 2016 Elsevier Inc. All rights reserved.

Age, time period, and birth cohort differences in self-esteem: Reexamining a cohort-sequential longitudinal study.

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Twenge, Jean M; Carter, Nathan T; Campbell, W Keith

2017-05-01

Orth, Trzesniewski, and Robins (2010) concluded that the nationally representative Americans' Changing Lives (ACL) cohort-sequential study demonstrated moderate to large age differences in self-esteem, and no birth cohort (generational) differences in the age trajectory. In a reanalysis of these data using 2 different statistical techniques, we find significant increases in self-esteem that could be attributed to birth cohort or time period. First, hierarchical linear modeling analyses with birth cohort as a continuous variable (vs. the multiple group formulation used by Orth et al.) find that birth cohort has a measurable influence on self-esteem through its interaction with age. Participants born in later years (e.g., 1960) were higher in self-esteem and were more likely to increase in self-esteem as they aged than participants born in earlier years (e.g., 1920). However, the estimated age trajectory up to age 60 is similar in Orth et al.'s results and in the results from our analyses including cohort. Second, comparing ACL respondents of the same age in 1986 versus 2002 (a time-lag design) yields significant birth cohort differences in self-esteem, with 2002 participants of the same age higher in self-esteem than those in 1986. Combined with some previous studies finding significant increases in self-esteem and positive self-views over time, these results suggest that cultural change in the form of cohort and time period cannot be ignored as influences in cross-sectional and longitudinal studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).