A Motivational Theory of Life-Span Development

PubMed Central

Heckhausen, Jutta; Wrosch, Carsten; Schulz, Richard

2010-01-01

This article had four goals. First, the authors identified a set of general challenges and questions that a life-span theory of development should address. Second, they presented a comprehensive account of their Motivational Theory of Life-Span Development. They integrated the model of optimization in primary and secondary control and the action-phase model of developmental regulation with their original life-span theory of control to present a comprehensive theory of development. Third, they reviewed the relevant empirical literature testing key propositions of the Motivational Theory of Life-Span Development. Finally, because the conceptual reach of their theory goes far beyond the current empirical base, they pointed out areas that deserve further and more focused empirical inquiry. PMID:20063963

Little evidence for intralocus sexual conflict over the optimal intake of nutrients for life span and reproduction in the black field cricket Teleogryllus commodus

PubMed Central

Rapkin, James; Archer, C. Ruth; Grant, Charles E.; Jensen, Kim; House, Clarissa M.; Wilson, Alastair J.; Hunt, John

2017-01-01

Abstract There is often large divergence in the effects of key nutrients on life span (LS) and reproduction in the sexes, yet nutrient intake is regulated in the same way in males and females given dietary choice. This suggests that the sexes are constrained from feeding to their sex‐specific nutritional optima for these traits. Here, we examine the potential for intralocus sexual conflict (IASC) over optimal protein and carbohydrate intake for LS and reproduction to constrain the evolution of sex‐specific nutrient regulation in the field cricket, Teleogryllus commodus. We show clear sex differences in the effects of protein and carbohydrate intake on LS and reproduction and strong positive genetic correlations between the sexes for the regulated intake of these nutrients. However, the between‐sex additive genetic covariance matrix had very little effect on the predicted evolutionary response of nutrient regulation in the sexes. Thus, IASC appears unlikely to act as an evolutionary constraint on sex‐specific nutrient regulation in T. commodus. This finding is supported by clear sexual dimorphism in the regulated intake of these nutrients under dietary choice. However, nutrient regulation did not coincide with the nutritional optima for LS or reproduction in either sex, suggesting that IASC is not completely resolved in T. commodus. PMID:28640400

The Cost of Uncertain Life Span*

PubMed Central

Edwards, Ryan D.

2012-01-01

A considerable amount of uncertainty surrounds the length of human life. The standard deviation in adult life span is about 15 years in the U.S., and theory and evidence suggest it is costly. I calibrate a utility-theoretic model of preferences over length of life and show that one fewer year in standard deviation is worth about half a mean life year. Differences in the standard deviation exacerbate cross-sectional differences in life expectancy between the U.S. and other industrialized countries, between rich and poor countries, and among poor countries. Accounting for the cost of life-span variance also appears to amplify recently discovered patterns of convergence in world average human well-being. This is partly for methodological reasons and partly because unconditional variance in human length of life, primarily the component due to infant mortality, has exhibited even more convergence than life expectancy. PMID:22368324

A Motivational Theory of Life-Span Development

ERIC Educational Resources Information Center

Heckhausen, Jutta; Wrosch, Carsten; Schulz, Richard

2010-01-01

This article had four goals. First, the authors identified a set of general challenges and questions that a life-span theory of development should address. Second, they presented a comprehensive account of their Motivational Theory of Life-Span Development. They integrated the model of optimization in primary and secondary control and the…

Defining wild-type life span in Caenorhabditis elegans.

PubMed

Gems, D; Riddle, D L

2000-05-01

The nematode Caenorhabditis elegans reproduces predominantly as a self-fertilizing hermaphrodite, and this drives laboratory populations to be homozygous at all genetic loci. Passaging of stocks can lead to fixation of spontaneous mutations, especially when the latter do not result in a selective disadvantage under laboratory conditions. Life span may be such a trait, since a comparison of six wild-type N2 lines derived from a common ancestor (but maintained separately in several laboratories) revealed four variants with median adult life spans ranging from 12.0 +/- 0.8 to 17.0 +/- 0.6 days at 20 degrees C. Fertility was also reduced in the two shortest-lived strains. We determined which life span most closely corresponds to that of the authentic wild type by two means. Firstly, N2 hermaphrodites were compared with seven C. elegans wild isolates. The latter were found to resemble only the longest-lived N2 strain. Comparison of male life spans of six lines also revealed additional strain variation. Secondly, life spans of F1 progeny issuing from crosses between N2 variants showed that short life spans were recessive, indicating that they result from loss-of-function mutations. We infer that the longest-lived N2 variant best resembles the original N2 isolate. This is the N2 male stock currently distributed by the Caenorhabditis Genetics Center.

Little evidence for intralocus sexual conflict over the optimal intake of nutrients for life span and reproduction in the black field cricket Teleogryllus commodus.

PubMed

Rapkin, James; Archer, C Ruth; Grant, Charles E; Jensen, Kim; House, Clarissa M; Wilson, Alastair J; Hunt, John

2017-09-01

There is often large divergence in the effects of key nutrients on life span (LS) and reproduction in the sexes, yet nutrient intake is regulated in the same way in males and females given dietary choice. This suggests that the sexes are constrained from feeding to their sex-specific nutritional optima for these traits. Here, we examine the potential for intralocus sexual conflict (IASC) over optimal protein and carbohydrate intake for LS and reproduction to constrain the evolution of sex-specific nutrient regulation in the field cricket, Teleogryllus commodus. We show clear sex differences in the effects of protein and carbohydrate intake on LS and reproduction and strong positive genetic correlations between the sexes for the regulated intake of these nutrients. However, the between-sex additive genetic covariance matrix had very little effect on the predicted evolutionary response of nutrient regulation in the sexes. Thus, IASC appears unlikely to act as an evolutionary constraint on sex-specific nutrient regulation in T. commodus. This finding is supported by clear sexual dimorphism in the regulated intake of these nutrients under dietary choice. However, nutrient regulation did not coincide with the nutritional optima for LS or reproduction in either sex, suggesting that IASC is not completely resolved in T. commodus. © 2017 The Author(s). Evolution published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Ancestral telomere shortening: a countdown that will increase mean life span?

PubMed

Hertzog, Radu G

2006-01-01

Like cells, all mammals have a limited life span. Among cells there are a few exceptions (e.g., immortal cells), among mammals not, even if some of them live longer. Many in vitro and in vivo studies support the consensus that telomere length is strongly correlated with life span. At the somatic cellular level, long telomeres have been associated with longer life span. A different situation can be seen in immortal cells, such as cancer, germ and stem cells, where telomeres are maintained by telomerase, a specialized reverse transcriptase that is involved in synthesis of telomeres. Irrespective of telomere length, if telomerase is active, telomeres can be maintained at a sufficient length to ensure cell survival. To the contrary, telomeres shorten progressively with each cell division and when a critical telomere length (Hayflick limit) is reached, the cells undergo senescence and subsequently apoptosis. In mammals, those with the longest telomeres (e.g., mice) have the shortest life span. Furthermore, the shorter the mean telomere length, the longer the mean life span, as observed in humans (10-14 kpb) and bowhead-whales (undetermined telomere length), which have the longest mean life span among mammals. Over the past centuries, human average life span has increased. The hypothesis presented here suggests that this continual increase in the mean life span could be due to a decrease of mean telomere length over the last hundreds years. Actually, the life span is not directly influenced by length of telomeres, but rather by telomere length - dependent gene expression pattern. According to Greider, "rather than average telomere length, it is the shortest telomere length that makes the biggest difference to a cell". In the context of fast-growing global elderly population due to increase in life expectancy, it also seem to be an age related increase in cancer incidence. Nevertheless, extending healthy life span could depend on how good cells achieve, during the

Decision-making heuristics and biases across the life span.

PubMed

Strough, Jonell; Karns, Tara E; Schlosnagle, Leo

2011-10-01

We outline a contextual and motivational model of judgment and decision-making (JDM) biases across the life span. Our model focuses on abilities and skills that correspond to deliberative, experiential, and affective decision-making processes. We review research that addresses links between JDM biases and these processes as represented by individual differences in specific abilities and skills (e.g., fluid and crystallized intelligence, executive functioning, emotion regulation, personality traits). We focus on two JDM biases-the sunk-cost fallacy (SCF) and the framing effect. We trace the developmental trajectory of each bias from preschool through middle childhood, adolescence, early adulthood, and later adulthood. We conclude that life-span developmental trajectories differ depending on the bias investigated. Existing research suggests relative stability in the framing effect across the life span and decreases in the SCF with age, including in later life. We highlight directions for future research on JDM biases across the life span, emphasizing the need for process-oriented research and research that increases our understanding of JDM biases in people's everyday lives. © 2011 New York Academy of Sciences.

Decision-making heuristics and biases across the life span

PubMed Central

Strough, JoNell; Karns, Tara E.; Schlosnagle, Leo

2013-01-01

We outline a contextual and motivational model of judgment and decision-making (JDM) biases across the life span. Our model focuses on abilities and skills that correspond to deliberative, experiential, and affective decision-making processes. We review research that addresses links between JDM biases and these processes as represented by individual differences in specific abilities and skills (e.g., fluid and crystallized intelligence, executive functioning, emotion regulation, personality traits). We focus on two JDM biases—the sunk-cost fallacy (SCF) and the framing effect. We trace the developmental trajectory of each bias from preschool through middle childhood, adolescence, early adulthood, and later adulthood. We conclude that life-span developmental trajectories differ depending on the bias investigated. Existing research suggests relative stability in the framing effect across the life span and decreases in the SCF with age, including in later life. We highlight directions for future research on JDM biases across the life span, emphasizing the need for process-oriented research and research that increases our understanding of JDM biases in people’s everyday lives. PMID:22023568

Visual Search Across the Life Span

ERIC Educational Resources Information Center

Hommel, Bernhard; Li, Karen Z. H.; Li, Shu-Chen

2004-01-01

Gains and losses in visual search were studied across the life span in a representative sample of 298 individuals from 6 to 89 years of age. Participants searched for single-feature and conjunction targets of high or low eccentricity. Search was substantially slowed early and late in life, age gradients were more pronounced in conjunction than in…

Teaching the Psychology of Aging: A Life-Span Perspective.

ERIC Educational Resources Information Center

Seltzer, Mildred M.

There is a vast body of literature devoted to an examination of life-span development. Several authors have described the characteristics of the life-span approach and have distinguished it from more traditional forms of psychology. Emphasis has been placed on the multidirectional and multidimensional nature of development and change, as well as…

Learning From Leaders: Life-span Trends in Olympians and Supercentenarians

PubMed Central

Berthelot, Geoffroy; Marck, Adrien; Noirez, Philippe; Latouche, Aurélien; Toussaint, Jean-François

2015-01-01

Life-span trends progression has worldwide practical implications as it may affect the sustainability of modern societies. We aimed to describe the secular life-span trends of populations with a propensity to live longer—Olympians and supercentenarians—under two hypotheses: an ongoing life-span extension versus a biologic “probabilistic barrier” limiting further progression. In a study of life-span densities (total number of life durations per birth date), we analyzed 19,012 Olympians and 1,205 supercentenarians deceased between 1900 and 2013. Among most Olympians, we observed a trend toward increased life duration. This trend, however, decelerates at advanced ages leveling off with the upper values with a perennial gap between Olympians and supercentenarians during the whole observation period. Similar tendencies are observed among supercentenarians, and over the last years, a plateau attests to a stable longevity pattern among the longest-lived humans. The common trends between Olympians and supercentenarians indicate similar mortality pressures over both populations that increase with age, scenario better explained by a biologic “barrier” forecast. PMID:25143003

Working memory and inhibitory control across the life span: Intrusion errors in the Reading Span Test.

PubMed

Robert, Christelle; Borella, Erika; Fagot, Delphine; Lecerf, Thierry; de Ribaupierre, Anik

2009-04-01

The aim of this study was to examine to what extent inhibitory control and working memory capacity are related across the life span. Intrusion errors committed by children and younger and older adults were investigated in two versions of the Reading Span Test. In Experiment 1, a mixed Reading Span Test with items of various list lengths was administered. Older adults and children recalled fewer correct words and produced more intrusions than did young adults. Also, age-related differences were found in the type of intrusions committed. In Experiment 2, an adaptive Reading Span Test was administered, in which the list length of items was adapted to each individual's working memory capacity. Age groups differed neither on correct recall nor on the rate of intrusions, but they differed on the type of intrusions. Altogether, these findings indicate that the availability of attentional resources influences the efficiency of inhibition across the life span.

Exploratory and problem-solving consumer behavior across the life span.

PubMed

Lesser, J A; Kunkel, S R

1991-09-01

Different cognitive functioning, social, and personality changes appear to occur systematically during the adult life span. This article synthesizes research on life span changes in order to develop age-specific models of shopping behavior. The models are tested within a naturalistic field study of shoppers.

Blade life span, structural investment, and nutrient allocation in giant kelp.

PubMed

Rodriguez, Gabriel E; Reed, Daniel C; Holbrook, Sally J

2016-10-01

The turnover of plant biomass largely determines the amount of energy flowing through an ecosystem and understanding the processes that regulate turnover has been of interest to ecologists for decades. Leaf life span theory has proven useful in explaining patterns of leaf turnover in relation to resource availability, but the predictions of this theory have not been tested for macroalgae. We measured blade life span, size, thickness, nitrogen content, pigment content, and maximum photosynthetic rate (P max) in the giant kelp (Macrocystis pyrifera) along a strong resource (light) gradient to test whether the predictions of leaf life span theory applied to this alga. We found that shorter blade life spans and larger blade areas were associated with increased light availability. In addition, nitrogen and P max decreased with blade age, and their decrease was greater in shorter lived blades. These observations are generally consistent with patterns observed for higher plants and the prevailing theory of leaf life span. By contrast, variation observed in pigments of giant kelp was inconsistent with that predicted by leaf life span theory, as blades growing in the most heavily shaded portion of the forest had the lowest chlorophyll content. This result may reflect the dual role of macroalgal blades in carbon fixation and nutrient absorption and the ability of giant kelp to modify blade physiology to optimize the acquisition of light and nutrients. Thus, the marine environment may place demands on resource acquisition and allocation that have not been previously considered with respect to leaf life span optimization.

Individual differences in personality change across the adult life span.

PubMed

Schwaba, Ted; Bleidorn, Wiebke

2018-06-01

A precise and comprehensive description of personality continuity and change across the life span is the bedrock upon which theories of personality development are built. Little research has quantified the degree to which individuals deviate from mean-level developmental trends. In this study, we addressed this gap by examining individual differences in personality trait change across the life span. Data came from a nationally representative sample of 9,636 Dutch participants who provided Big Five self-reports at five assessment waves across 7 years. We divided our sample into 14 age groups (ages 16-84 at initial measurement) and estimated latent growth curve models to describe individual differences in personality change across the study period for each trait and age group. Across the adult life span, individual differences in personality change were small but significant until old age. For Openness, Conscientiousness, Extraversion, and Agreeableness, individual differences in change were most pronounced in emerging adulthood and decreased throughout midlife and old age. For Emotional Stability, individual differences in change were relatively consistent across the life span. These results inform theories of life span development and provide future directions for research on the causes and conditions of personality change. © 2017 Wiley Periodicals, Inc.

Comparative transcriptional profiling identifies takeout as a gene that regulates life span

PubMed Central

Bauer, Johannes; Antosh, Michael; Chang, Chengyi; Schorl, Christoph; Kolli, Santharam; Neretti, Nicola; Helfand, Stephen L.

2010-01-01

A major challenge in translating the positive effects of dietary restriction (DR) for the improvement of human health is the development of therapeutic mimics. One approach to finding DR mimics is based upon identification of the proximal effectors of DR life span extension. Whole genome profiling of DR in Drosophila shows a large number of changes in gene expression, making it difficult to establish which changes are involved in life span determination as opposed to other unrelated physiological changes. We used comparative whole genome expression profiling to discover genes whose change in expression is shared between DR and two molecular genetic life span extending interventions related to DR, increased dSir2 and decreased Dmp53 activity. We find twenty-one genes shared among the three related life span extending interventions. One of these genes, takeout, thought to be involved in circadian rhythms, feeding behavior and juvenile hormone binding is also increased in four other life span extending conditions: Rpd3, Indy, chico and methuselah. We demonstrate takeout is involved in longevity determination by specifically increasing adult takeout expression and extending life span. These studies demonstrate the power of comparative whole genome transcriptional profiling for identifying specific downstream elements of the DR life span extending pathway. PMID:20519778

Learning From Leaders: Life-span Trends in Olympians and Supercentenarians.

PubMed

Antero-Jacquemin, Juliana da Silva; Berthelot, Geoffroy; Marck, Adrien; Noirez, Philippe; Latouche, Aurélien; Toussaint, Jean-François

2015-08-01

Life-span trends progression has worldwide practical implications as it may affect the sustainability of modern societies. We aimed to describe the secular life-span trends of populations with a propensity to live longer-Olympians and supercentenarians-under two hypotheses: an ongoing life-span extension versus a biologic "probabilistic barrier" limiting further progression. In a study of life-span densities (total number of life durations per birth date), we analyzed 19,012 Olympians and 1,205 supercentenarians deceased between 1900 and 2013. Among most Olympians, we observed a trend toward increased life duration. This trend, however, decelerates at advanced ages leveling off with the upper values with a perennial gap between Olympians and supercentenarians during the whole observation period. Similar tendencies are observed among supercentenarians, and over the last years, a plateau attests to a stable longevity pattern among the longest-lived humans. The common trends between Olympians and supercentenarians indicate similar mortality pressures over both populations that increase with age, scenario better explained by a biologic "barrier" forecast. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America.

Understanding retirement: the promise of life-span developmental frameworks.

PubMed

Löckenhoff, Corinna E

2012-09-01

The impending retirement of large population cohorts creates a pressing need for practical interventions to optimize outcomes at the individual and societal level. This necessitates comprehensive theoretical models that acknowledge the multi-layered nature of the retirement process and shed light on the dynamic mechanisms that drive longitudinal patterns of adjustment. The present commentary highlights ways in which contemporary life-span developmental frameworks can inform retirement research, drawing on the specific examples of Bronfenbrenner's Ecological Model, Baltes and Baltes Selective Optimization with Compensation Framework, Schulz and Heckhausen's Motivational Theory of Life-Span Development, and Carstensen's Socioemotional Selectivity Theory. Ultimately, a life-span developmental perspective on retirement offers not only new interpretations of known phenomena but may also help to identify novel directions for future research as well as promising pathways for interventions.

Developmental Regulation across the Life Span: Toward a New Synthesis

ERIC Educational Resources Information Center

Haase, Claudia M.; Heckhausen, Jutta; Wrosch, Carsten

2013-01-01

How can individuals regulate their own development to live happy, healthy, and productive lives? Major theories of developmental regulation across the life span have been proposed (e.g., dual-process model of assimilation and accommodation; motivational theory of life-span development; model of selection, optimization, and compensation), but they…

Connecting Life Span Development with the Sociology of the Life Course: A New Direction.

PubMed

Gilleard, Chris; Higgs, Paul

2016-04-01

The life course has become a topic of growing interest within the social sciences. Attempts to link this sub-discipline with life span developmental psychology have been called for but with little sign of success. In this paper, we seek to address three interlinked issues concerning the potential for a more productive interchange between life course sociology and life span psychology. The first is to try to account for the failure of these two sub-disciplines to achieve any deepening engagement with each other, despite the long-expressed desirability of that goal; the second is to draw attention to the scope for enriching the sociology of the life course through Erik Erikson's model of life span development; and the last is the potential for linking Eriksonian theory with current debates within mainstream sociology about the processes involved in 'individualisation' and 'self-reflexivity' as an alternative entry point to bring together these two fields of work.

Connecting Life Span Development with the Sociology of the Life Course: A New Direction

PubMed Central

Gilleard, Chris; Higgs, Paul

2015-01-01

The life course has become a topic of growing interest within the social sciences. Attempts to link this sub-discipline with life span developmental psychology have been called for but with little sign of success. In this paper, we seek to address three interlinked issues concerning the potential for a more productive interchange between life course sociology and life span psychology. The first is to try to account for the failure of these two sub-disciplines to achieve any deepening engagement with each other, despite the long-expressed desirability of that goal; the second is to draw attention to the scope for enriching the sociology of the life course through Erik Erikson’s model of life span development; and the last is the potential for linking Eriksonian theory with current debates within mainstream sociology about the processes involved in ‘individualisation’ and ‘self-reflexivity’ as an alternative entry point to bring together these two fields of work. PMID:27041774

Getting together: Social contact frequency across the life span.

PubMed

Sander, Julia; Schupp, Jürgen; Richter, David

2017-08-01

Frequent social interactions are strongly linked to positive affect, longevity, and good health. Although there has been extensive research on changes in the size of social networks over time, little attention has been given to the development of contact frequency across the life span. In this cohort-sequential longitudinal study, we examined intraindividual changes in the frequency of social contact with family and nonfamily members, and potential moderators of these changes. The data come from the 1998, 2003, 2008, and 2013 waves of the German Socio-Economic Panel (SOEP) study (N = 36,716; age range: 17-85 years). Using latent growth curve analysis, we found that the frequency of in-person contact with family members remained relatively stable across the life span. In contrast, the frequency of visits to and from nonfamily members (neighbors, friends, and acquaintances) declined following a cubic trajectory and dropped below the frequency of family visits when respondents were in their mid-30s. Relationship status and gender had a slight effect on both of these relationship trajectories. Subjective current health status and employment status influenced the life span trajectory of nonfamily social contact only. Changes of residence and the birth of a child, both of which constitute major turning points in the life course, did not affect the life span trajectory of either family or nonfamily in-person contact. The findings are discussed here in the context of earlier findings and in relation to socioemotional selectivity and social convoy theory and the evolutionary life history approach. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Reproductive Life Planning: Raising the Questions.

PubMed

Morse, Jessica E; Moos, Merry-K

2018-04-01

Introduction Unintended pregnancy has been a concerning public health problem for decades. As we begin to understand the complexities of pregnancy intention and how women experience these pregnancies, reproductive life planning offers a paradigm shift. Methods Reproductive life planning is a patient-centered approach that places a patient's reproductive preferences-whether concrete or ambivalent-at the forefront of her clinical care. Results This process grants women and men the opportunity to consider how reproduction fits within the context of their broader lives. Within a clinical encounter, reproductive life planning allows counseling and care to be tailored to patient preferences. Discussion Although there is great potential for positive public health impacts in unintended pregnancy, contraceptive use and improved preconception health, the true benefit lies within reinforcing reproductive empowerment. Despite recommendations for universal adoption, many questions remain regarding implementation, equity and outcomes.

Life-span perspective of personality in dementia.

PubMed

Kolanowski, A M; Whall, A L

1996-01-01

To propose an alternative view of personality change in dementia by presenting existing evidence for the continuity of personality. As the population continues to age, dementing illnesses will account for a greater proportion of morbidity and mortality; the care of these people will have a significant effect on the health care system. Life-span perspective of personality continuity. SCOPE METHOD: Review of current literature on personality in dementia using Medline, 1980-1994; CINAHL, 1990-1994; and Psych Lit., 1980-1994. Although there are systematic shifts in personality with dementia, individuals tend to maintain their unique pattern of premorbid personality traits. The personalities of dementia patients seem to reflect adaptive patterns that served them in the past. Use of a life-span perspective can enhance individualized care for demented patients and advance theory development.

78. VIEW SHOWING PLACEMENT OF LIFE SPAN SHOE ON PIER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

78. VIEW SHOWING PLACEMENT OF LIFE SPAN SHOE ON PIER 6, LOOKING NORTH, March 5, 1935 - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

Sensorimotor Synchronization across the Life Span

ERIC Educational Resources Information Center

Drewing, Knut; Aschersleben, Gisa; Li, Shu-Chen

2006-01-01

The present study investigates the contribution of general processing resources as well as other more specific factors to the life-span development of sensorimotor synchronization and its component processes. Within a synchronization tapping paradigm, a group of 286 participants, 6 to 88 years of age, were asked to synchronize finger taps with…

Dietary Interventions to Extend Life Span and Health Span Based on Calorie Restriction

PubMed Central

Minor, Robin K.; Allard, Joanne S.; Younts, Caitlin M.; Ward, Theresa M.

2010-01-01

The societal impact of obesity, diabetes, and other metabolic disorders continues to rise despite increasing evidence of their negative long-term consequences on health span, longevity, and aging. Unfortunately, dietary management and exercise frequently fail as remedies, underscoring the need for the development of alternative interventions to successfully treat metabolic disorders and enhance life span and health span. Using calorie restriction (CR)—which is well known to improve both health and longevity in controlled studies—as their benchmark, gerontologists are coming closer to identifying dietary and pharmacological therapies that may be applicable to aging humans. This review covers some of the more promising interventions targeted to affect pathways implicated in the aging process as well as variations on classical CR that may be better suited to human adaptation. PMID:20371545

The Rate of Source Memory Decline across the Adult Life Span

ERIC Educational Resources Information Center

Cansino, Selene; Estrada-Manilla, Cinthya; Hernandez-Ramos, Evelia; Martinez-Galindo, Joyce Graciela; Torres-Trejo, Frine; Gomez-Fernandez, Tania; Ayala-Hernandez, Mariana; Osorio, David; Cedillo-Tinoco, Melisa; Garces-Flores, Lissete; Gomez-Melgarejo, Sandra; Beltran-Palacios, Karla; Guadalupe Garcia-Lazaro, Haydee; Garcia-Gutierrez, Fabiola; Cadena-Arenas, Yadira; Fernandez-Apan, Luisa; Bartschi, Andrea; Resendiz-Vera, Julieta; Rodriguez-Ortiz, Maria Dolores

2013-01-01

Previous studies have suggested that the ability to remember contextual information related to specific episodic experiences declines with advancing age; however, the exact moment in the adult life span when this deficit begins is still controversial. Source memory for spatial information was tested in a life span sample of 1,500 adults between…

Sex differences in life span: Females homozygous for the X chromosome do not suffer the shorter life span predicted by the unguarded X hypothesis.

PubMed

Brengdahl, Martin; Kimber, Christopher M; Maguire-Baxter, Jack; Friberg, Urban

2018-03-01

Life span differs between the sexes in many species. Three hypotheses to explain this interesting pattern have been proposed, involving different drivers: sexual selection, asymmetrical inheritance of cytoplasmic genomes, and hemizygosity of the X(Z) chromosome (the unguarded X hypothesis). Of these, the unguarded X has received the least experimental attention. This hypothesis suggests that the heterogametic sex suffers a shortened life span because recessive deleterious alleles on its single X(Z) chromosome are expressed unconditionally. In Drosophila melanogaster, the X chromosome is unusually large (∼20% of the genome), providing a powerful model for evaluating theories involving the X. Here, we test the unguarded X hypothesis by forcing D. melanogaster females from a laboratory population to express recessive X-linked alleles to the same degree as males, using females exclusively made homozygous for the X chromosome. We find no evidence for reduced life span or egg-to-adult viability due to X homozygozity. In contrast, males and females homozygous for an autosome both suffer similar, significant reductions in those traits. The logic of the unguarded X hypothesis is indisputable, but our results suggest that the degree to which recessive deleterious X-linked alleles depress performance in the heterogametic sex appears too small to explain general sex differences in life span. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

Spatial abilities across the adult life span.

PubMed

Borella, Erika; Meneghetti, Chiara; Ronconi, Lucia; De Beni, Rossana

2014-02-01

The study investigates age-related effects across the adult life span on spatial abilities (testing subabilities based on a distinction between spatial visualization, mental rotation, and perspective taking) and spatial self-assessments. The sample consisted of 454 participants (223 women and 231 men) from 20 to 91 years of age. Results showed nonlinear age-related effects for spatial visualization and perspective taking but linear effects for mental rotation; few or no age-related effects were found for spatial self-assessments. Working memory accounted for only a small proportion of the variance in all spatial tasks and had no effect on spatial self-assessments. Overall, our findings suggest that the influence of age on spatial skills across the adult life span is considerable, but the effects of age change as a function of the spatial task considered, and the effect on spatial self-assessment is more marginal.

A CRTCal link between energy and life span.

PubMed

Brunet, Anne

2011-04-06

Cutting down calories prolongs life, but how this works remains largely unknown. A recent study in Nature (Mair et al., 2011) shows that life span extension triggered by the energy-sensing protein kinase AMPK is mediated by an evolutionarily conserved transcriptional circuit involving CRTC-1 and CREB. Copyright © 2011 Elsevier Inc. All rights reserved.

Sibling Communication Functions across the Life-Span.

ERIC Educational Resources Information Center

Myers, Scott A.; Smith, Ronda L.; Sonnier, Michelle F.

An investigation examined whether perceived use of sibling functional communication skills differed across the life-span. Participants were recruited through university students enrolled in an introductory communication course at a southern university. All students received extra credit for recruiting two participants. Potential participants were…

Herbal Supplement Extends Life Span Under Some Environmental Conditions and Boosts Stress Resistance

PubMed Central

Villeponteau, Bryant; Matsagas, Kennedy; Nobles, Amber C.; Rizza, Cristina; Horwitz, Marc; Benford, Gregory; Mockett, Robin J.

2015-01-01

Genetic studies indicate that aging is modulated by a great number of genetic pathways. We have used Drosophila longevity and stress assays to test a multipath intervention strategy. To carry out this strategy, we supplemented the flies with herbal extracts (SC100) that are predicted to modulate the expression of many genes involved in aging and stress resistance, such as mTOR, NOS, NF-KappaB, and VEGF. When flies were housed in large cages with SC100 added, daily mortality rates of both male and female flies were greatly diminished in mid to late life. Surprisingly, SC100 also stabilized midlife mortality rate increases so as to extend the maximum life span substantially beyond the limits previously reported for D. melanogaster. Under these conditions, SC100 also promoted robust resistance to partial starvation stress and to heat stress. Fertility was the same initially in both treated and control flies, but it became significantly higher in treated flies at older ages as the fertility of control flies declined. Mean and maximum life spans of flies in vials at the same test site were also extended by SC100, but the life spans were short in absolute terms. In contrast, at an independent test site where stress was minimized, the flies exhibited much longer mean life spans, but the survival curves became highly rectangular and the effects of SC100 on both mean and maximum life spans declined greatly or were abolished. The data indicate that SC100 is a novel herbal mix with striking effects on enhancing Drosophila stress resistance and life span in some environments, while minimizing mid to late life mortality rates. They also show that the environment and other factors can have transformative effects on both the length and distribution of survivorship, and on the ability of SC100 to extend the life span. PMID:25879540

Studying the replicative life span of yeast cells.

PubMed

Sinclair, David A

2013-01-01

The budding yeast Saccharomyces cerevisiae is a useful model for elucidating the pathways that control life span and the influence of environmental factors, such as calorie restriction (CR). For 75 years, CR has been studied for its ability to delay diseases of aging in mammals, from cancer to cardiovascular disease (McCay et al., Nutr Rev 33:241-243, 1975). In many other species, reducing calorie intake extends life span, including unicellular organisms (Jiang et al., FASEB J 14:2135-2137, 2000; Lin et al., Science 289:2126-2128, 2000), invertebrates (Rogina and Helfand, Proc Natl Acad Sci U S A 101:15998-16003, 2004), and rodents (Martín-Montalvo et al., Oncogene 30:505-520, 2011). Here we describe how to calorically restrict yeast cells, the methods used to determine the replicative life span (RLS) of budding yeast cells, how to selectively kill daughter cells using the mother enrichment program (MEP), how to measure recombination frequency at the rDNA locus, how to isolate large quantities of old cells, and how to analyze the circular forms of DNA known as extrachromosomal rDNA circles (ERCs), a cause of aging in S. cerevisiae (Petes, Cell 19:765-774, 1980; Sinclair and Guarente, Cell 91:1033-1042, 1997; Defossez et al., Mol Cell 3:447-455, 1999).

Qualitative Exploration of Acculturation and Life-Span Issues of Elderly Asian Americans

ERIC Educational Resources Information Center

Lee, Jee Hyang; Heo, Nanseol; Lu, Junfei; Portman, Tarrell Awe Agahe

2013-01-01

Awareness of aging issues across diverse populations begins the journey toward counselors becoming culturally competent across client life spans. Understanding the life-span experiences of cultural groups is important for helping professionals. The purpose of this research was to gain insight into the qualitative experiences of Asian American…

Spatial Abilities across the Adult Life Span

ERIC Educational Resources Information Center

Borella, Erika; Meneghetti, Chiara; Ronconi, Lucia; De Beni, Rossana

2014-01-01

The study investigates age-related effects across the adult life span on spatial abilities (testing subabilities based on a distinction between spatial visualization, mental rotation, and perspective taking) and spatial self-assessments. The sample consisted of 454 participants (223 women and 231 men) from 20 to 91 years of age. Results showed…

ω-6 Polyunsaturated fatty acids extend life span through the activation of autophagy

PubMed Central

O'Rourke, Eyleen J.; Kuballa, Petric; Xavier, Ramnik; Ruvkun, Gary

2013-01-01

Adaptation to nutrient scarcity depends on the activation of metabolic programs to efficiently use internal reserves of energy. Activation of these programs in abundant food regimens can extend life span. However, the common molecular and metabolic changes that promote adaptation to nutritional stress and extend life span are mostly unknown. Here we present a response to fasting, enrichment of ω-6 polyunsaturated fatty acids (PUFAs), which promotes starvation resistance and extends Caenorhabditis elegans life span. Upon fasting, C. elegans induces the expression of a lipase, which in turn leads to an enrichment of ω-6 PUFAs. Supplementing C. elegans culture media with these ω-6 PUFAs increases their resistance to starvation and extends their life span in conditions of food abundance. Supplementation of C. elegans or human epithelial cells with these ω-6 PUFAs activates autophagy, a cell recycling mechanism that promotes starvation survival and slows aging. Inactivation of C. elegans autophagy components reverses the increase in life span conferred by supplementing the C. elegans diet with these fasting-enriched ω-6 PUFAs. We propose that the salubrious effects of dietary supplementation with ω-3/6 PUFAs (fish oils) that have emerged from epidemiological studies in humans may be due to a similar activation of autophagic programs. PMID:23392608

Life span effects of Hypericum perforatum extracts on Caenorhabditis elegans under heat stress.

PubMed

Kılıçgün, Hasan; Göksen, Gülden

2012-10-01

The beneficial effects of antioxidants in plants are mainly extrapolated from in vitro studies or short-term dietary supplementation studies. Due to cost and duration, relatively little is known about whether dietary antioxidants are beneficial in whole animals' life span or not. To address this question, under heat stress (35°C), Hypericum perforatum was extracted with petroleum ether and the nematodes Caenorhabditis elegans exposed to three different extract concentrations (1mg/mL, 0.1mg/mL, 0.01mg/mL) of H. perforatum. We report that Hypericum perforatum extracts did not increase life span and slow aging related increase in C. elegans. Moreover, one fraction (1mg/mL) increased declines of C. elegans life span and thermotolerance. Given this mounting evidence for life span role of H. perforatum in the presence of heat stress in vivo, the question whether H. perforatum acts as a prooxidant or an antioxidant in vivo under heat stress arises.

Life span effects of Hypericum perforatum extracts on Caenorhabditis elegans under heat stress

PubMed Central

Kılıçgün, Hasan; Göksen, Gülden

2012-01-01

Background: The beneficial effects of antioxidants in plants are mainly extrapolated from in vitro studies or short-term dietary supplementation studies. Due to cost and duration, relatively little is known about whether dietary antioxidants are beneficial in whole animals’ life span or not. Materials and Methods: To address this question, under heat stress (35°C), Hypericum perforatum was extracted with petroleum ether and the nematodes Caenorhabditis elegans exposed to three different extract concentrations (1mg/mL, 0.1mg/mL, 0.01mg/mL) of H. perforatum. Results: We report that Hypericum perforatum extracts did not increase life span and slow aging related increase in C. elegans. Moreover, one fraction (1mg/mL) increased declines of C. elegans life span and thermotolerance. Conclusion: Given this mounting evidence for life span role of H. perforatum in the presence of heat stress in vivo, the question whether H. perforatum acts as a prooxidant or an antioxidant in vivo under heat stress arises. PMID:24082638

Attitudes Toward Death Across the Life Span.

ERIC Educational Resources Information Center

Maiden, Robert; Walker, Gail

To understand the change and development of people's attitudes toward death over the life span, a 62-item attitude questionnaire on death and dying was administered to 90 adults. Participants included five females and five males in each of nine age categories: 18-20, 20-24, 25-29, 30-34, 35-39, 40-49, 50-59, 60-64, and 65 or older. Participants…

Life-span extension by a metacaspase in the yeast Saccharomyces cerevisiae.

PubMed

Hill, Sandra Malmgren; Hao, Xinxin; Liu, Beidong; Nyström, Thomas

2014-06-20

Single-cell species harbor ancestral structural homologs of caspase proteases, although the evolutionary benefit of such apoptosis-related proteins in unicellular organisms is unclear. Here, we found that the yeast metacaspase Mca1 is recruited to the insoluble protein deposit (IPOD) and juxtanuclear quality-control compartment (JUNQ) during aging and proteostatic stress. Elevating MCA1 expression counteracted accumulation of unfolded proteins and aggregates and extended life span in a heat shock protein Hsp104 disaggregase- and proteasome-dependent manner. Consistent with a role in protein quality control, genetic interaction analysis revealed that MCA1 buffers against deficiencies in the Hsp40 chaperone YDJ1 in a caspase cysteine-dependent manner. Life-span extension and aggregate management by Mca1 was only partly dependent on its conserved catalytic cysteine, which suggests that Mca1 harbors both caspase-dependent and independent functions related to life-span control. Copyright © 2014, American Association for the Advancement of Science.

Influence of resveratrol on oxidative stress resistance and life span in Caenorhabditis elegans.

PubMed

Chen, Wei; Rezaizadehnajafi, Leila; Wink, Michael

2013-05-01

Resveratrol (3,5,4'-trihydroxy-trans-stilbene), a polyphenol from red wine, has been reported to be beneficial in cases of ageing-related cardiovascular and neurodegenerative diseases owing to its property to reduce oxidative stress. Previous studies on the longevity promoting effect of resveratrol have been partly inconclusive, therefore we set out to investigate whether resveratrol at least promoted longevity in Caenorhabditis elegans under acute oxidative stress conditions. C. elegans was cultured under standard conditions with or without resveratrol. After exposure to juglone-induced acute oxidative stress, the survival rate and hsp-16.2::GFP expression were measured. The influence of resveratrol on life span was recorded also under oxidative stress induced by high glucose concentrations in the growth medium. No extension of the normal life span of C. elegans was observed either in liquid or solid growth media containing different concentrations of resveratrol. However, resveratrol alleviated juglone-induced lethal oxidative stress, and significantly prolonged the life span of C. elegans under conditions of acute oxidative damage and oxidative stress caused by high concentrations of glucose. Resveratrol, as an antioxidant, ameliorated oxidative stress in vivo but did not extend the life span of C. elegans under normal conditions. However, resveratrol did extend life span under conditions of oxidative stress. © 2013 The Authors. JPP © 2013 Royal Pharmaceutical Society.

How long will my mouse live? Machine learning approaches for prediction of mouse life span.

PubMed

Swindell, William R; Harper, James M; Miller, Richard A

2008-09-01

Prediction of individual life span based on characteristics evaluated at middle-age represents a challenging objective for aging research. In this study, we used machine learning algorithms to construct models that predict life span in a stock of genetically heterogeneous mice. Life-span prediction accuracy of 22 algorithms was evaluated using a cross-validation approach, in which models were trained and tested with distinct subsets of data. Using a combination of body weight and T-cell subset measures evaluated before 2 years of age, we show that the life-span quartile to which an individual mouse belongs can be predicted with an accuracy of 35.3% (+/-0.10%). This result provides a new benchmark for the development of life-span-predictive models, but improvement can be expected through identification of new predictor variables and development of computational approaches. Future work in this direction can provide tools for aging research and will shed light on associations between phenotypic traits and longevity.

Friendship in childhood and adulthood: lessons across the life span.

PubMed

Sherman, A M; de Vries, B; Lansford, J E

2000-01-01

Friendship occupies an important place in the growing body of literature in child development and gerontological research. As such, it may be useful for researchers from both fields to consider what can be learned from work carried out in each tradition. Therefore, we present a selected review of topics in friendship research across the life span. Through discussion of the value of friendship, the development of friendship, challenges to friendship, the gendered nature of friendship, and the connection between friends and family, points of commonality and contrast are identified. We conclude by presenting possible avenues for future investigation for researchers interested in friendship at any point in the life span.

Mitochondrial Reactive Oxygen Species Trigger Hypoxia-Inducible Factor-Dependent Extension of the Replicative Life Span during Hypoxia▿

PubMed Central

Bell, Eric L.; Klimova, Tatyana A.; Eisenbart, James; Schumacker, Paul T.; Chandel, Navdeep S.

2007-01-01

Physiological hypoxia extends the replicative life span of human cells in culture. Here, we report that hypoxic extension of replicative life span is associated with an increase in mitochondrial reactive oxygen species (ROS) in primary human lung fibroblasts. The generation of mitochondrial ROS is necessary for hypoxic activation of the transcription factor hypoxia-inducible factor (HIF). The hypoxic extension of replicative life span is ablated by a dominant negative HIF. HIF is sufficient to induce telomerase reverse transcriptase mRNA and telomerase activity and to extend replicative life span. Furthermore, the down-regulation of the von Hippel-Lindau tumor suppressor protein by RNA interference increases HIF activity and extends replicative life span under normoxia. These findings provide genetic evidence that hypoxia utilizes mitochondrial ROS as signaling molecules to activate HIF-dependent extension of replicative life span. PMID:17562866

Causes and consequences of variation in conifer leaf life-span

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reich, P.B.; Koike, T.; Gower, S.T.

1995-07-01

Species with mutually supporting traits, such as high N{sub mass}, SLA, and A{sub mass}, and short leaf life-span, tend to inhabit either generally resource-rich environments or spatial and/or temporal microhabitats that are resource-rich in otherwise more limited habitats (e.g., {open_quotes}precipitation{close_quotes} ephemerals in warm deserts or spring ephemerals in the understory of temperate deciduous forests). In contrast, species with long leaf life-span often support foliage with low SLA, N{sub mass}, and A{sub mass}, and often grow in low-temperature limited, dry, and/or nutrient-poor environments. The contrast between evergreen and deciduous species, and the implications that emerge from such comparisons, can be consideredmore » a paradigm of modern ecological theory. However, based on the results of Reich et al. (1992) and Gower et al. (1993), coniferous species with foliage that persists for 9-10 years are likely to assimilate and allocate carbon and nutrients differently than other evergreen conifers that retain foliage for 2-3 years. Thus, attempts to contrast ecophysiological or ecosystem characteristics of evergreen versus deciduous life forms may be misleading, and pronounced differences among evergreen conifers may be ignored. Clearly, the deciduous-evergreen contrast, although useful in several ways, should be viewed from the broader perspective of a gradient in leaf life-span.« less

Yeast MRX deletions have short chronological life span and more triacylglycerols.

PubMed

Kanagavijayan, Dhanabalan; Rajasekharan, Ram; Srinivasan, Malathi

2016-02-01

Saccharomyces cerevisiae is an excellent model organism for lipid research. Here, we have used yeast haploid RAdiation Damage (RAD) deletion strains to study life span and lipid storage patterns. RAD genes are mainly involved in DNA repair mechanism and hence, their deletions have resulted in shorter life span. Viable RAD mutants were screened for non-polar lipid content, and some of the mutants showed significantly high amounts of triacylglycerol (TAG) and steryl ester, besides short chronological life span. Among these, RAD50, MRE11 and XRS2 form a complex, MRX that is involved in homologous recombination that showed an increase in the amount of TAG. Microarray data of single MRX deletions revealed that besides DNA damage signature genes, lipid metabolism genes are also differentially expressed. Lipid biosynthetic genes (LPP1, SLC1) were upregulated and lipid hydrolytic gene (TGL3) was downregulated. We observed that rad50Δ, mre11Δ, xrs2Δ and mrxΔ strains have high number of lipid droplets (LDs) with fragmented mitochondria. These mutants have a short chronological life span compared to wild type. Aged wild-type cells also accumulated TAG with LDs of ∼2.0 μm in diameter. These results suggest that TAG accumulation and big size LDs could be possible markers for premature or normal aging. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Emotional Egocentricity Bias Across the Life-Span.

PubMed

Riva, Federica; Triscoli, Chantal; Lamm, Claus; Carnaghi, Andrea; Silani, Giorgia

2016-01-01

In our daily lives, we often have to quickly estimate the emotions of our conspecifics in order to have successful social interactions. While this estimation process seems quite easy when we are ourselves in a neutral or equivalent emotional state, it has recently been shown that in case of incongruent emotional states between ourselves and the others, our judgments can be biased. This phenomenon, introduced to the literature with the term Emotional Egocentricity Bias (EEB), has been found to occur in young adults and, to a greater extent, in children. However, how the EEB changes across the life-span from adolescence to old age has been largely unexplored. In this study, we recruited 114 female participants subdivided in four cohorts (adolescents, young adults, middle-aged adults, older adults) to examine EEB age-related changes. Participants were administered with a recently developed paradigm which, by making use of visuo-tactile stimulation that elicits conflicting feelings in paired participants, allows the valid and reliable exploration of the EEB. Results highlighted a U-shape relation between age and EEB, revealing enhanced emotional egocentricity in adolescents and older adults compared to young and middle-aged adults. These results are in line with the neuroscientific literature which has recently shown that overcoming the EEB is associated with a greater activation of a portion of the parietal lobe, namely the right Supramarginal Gyrus (rSMG). This is an area that reaches full maturation by the end of adolescence and goes through an early decay. Thus, the age-related changes of the EEB could be possibly due to the life-span development of the rSMG. This study is the first one to show the quadratic relation between age and the EEB and set a milestone for further research exploring the neural correlates of the life-span development of the EEB. Future studies are needed in order to generalize these results to the male population and to explore gender

Seasonal trends in Ceratitis capitata reproductive potential derived from live-caught females in Greece

PubMed Central

Kouloussis, Nikos A.; Papadopoulos, Nikos T.; Katsoyannos, Byron I.; Müller, Hans-Georg; Wang, Jane-Ling; Su, Yu-Ru; Molleman, Freerk; Carey, James R.

2012-01-01

Reproductive data of individual insects are extremely hard to collect under natural conditions, thus the study of research questions related to oviposition has not advanced. Patterns of oviposition are often inferred only indirectly, through monitoring of host infestation, whereas the influence of age structure and several other factors on oviposition remains unknown. Using a new approach, in this article, we live-trapped wild Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) females on the Greek island of Chios during two field seasons. For their remaining lifetime, these females were placed individually in small cages and their daily oviposition was monitored. Reproduction rates between cohorts from different collection dates were then compared. The results showed that in the different captive cohorts the average remaining lifetime and reproduction were highly variable within and between seasons. Multivariate regression analysis showed that the month of capture had a significant effect on captive life span, average daily reproduction, and patterns of egg laying. The effect of year was significant on reproduction, but not on captive life span. These differences between sampling periods probably reflect differences in the availability of hosts and other factors that vary during the season and affect age structure and reproduction. Using a non-parametric generalized additive model, we found a statistically significant correlation between the captive life span and the average daily reproduction. These findings and the experimental approach have several important implications. PMID:22791908

Structural covariance networks across the life span, from 6 to 94 years of age.

PubMed

DuPre, Elizabeth; Spreng, R Nathan

2017-10-01

Structural covariance examines covariation of gray matter morphology between brain regions and across individuals. Despite significant interest in the influence of age on structural covariance patterns, no study to date has provided a complete life span perspective-bridging childhood with early, middle, and late adulthood-on the development of structural covariance networks. Here, we investigate the life span trajectories of structural covariance in six canonical neurocognitive networks: default, dorsal attention, frontoparietal control, somatomotor, ventral attention, and visual. By combining data from five open-access data sources, we examine the structural covariance trajectories of these networks from 6 to 94 years of age in a sample of 1,580 participants. Using partial least squares, we show that structural covariance patterns across the life span exhibit two significant, age-dependent trends. The first trend is a stable pattern whose integrity declines over the life span. The second trend is an inverted-U that differentiates young adulthood from other age groups. Hub regions, including posterior cingulate cortex and anterior insula, appear particularly influential in the expression of this second age-dependent trend. Overall, our results suggest that structural covariance provides a reliable definition of neurocognitive networks across the life span and reveal both shared and network-specific trajectories.

Structural covariance networks across the life span, from 6 to 94 years of age

PubMed Central

DuPre, Elizabeth; Spreng, R. Nathan

2017-01-01

Structural covariance examines covariation of gray matter morphology between brain regions and across individuals. Despite significant interest in the influence of age on structural covariance patterns, no study to date has provided a complete life span perspective—bridging childhood with early, middle, and late adulthood—on the development of structural covariance networks. Here, we investigate the life span trajectories of structural covariance in six canonical neurocognitive networks: default, dorsal attention, frontoparietal control, somatomotor, ventral attention, and visual. By combining data from five open-access data sources, we examine the structural covariance trajectories of these networks from 6 to 94 years of age in a sample of 1,580 participants. Using partial least squares, we show that structural covariance patterns across the life span exhibit two significant, age-dependent trends. The first trend is a stable pattern whose integrity declines over the life span. The second trend is an inverted-U that differentiates young adulthood from other age groups. Hub regions, including posterior cingulate cortex and anterior insula, appear particularly influential in the expression of this second age-dependent trend. Overall, our results suggest that structural covariance provides a reliable definition of neurocognitive networks across the life span and reveal both shared and network-specific trajectories. PMID:29855624

Explanatory style across the life span: evidence for stability over 52 years.

PubMed

Burns, M O; Seligman, M E

1989-03-01

Analyzed explanatory style across the life span. 30 Ss whose average age was 72 responded to questions about their current life and provided diaries or letters written in their youth, an average of 52 years earlier. A blind content analysis of explanatory style derived from these 2 sources revealed that explanatory style for negative events was stable throughout adult life (r = .54, p less than .002). In contrast, there appeared to be no stability of explanatory style for positive events between the same 2 time periods. These results suggest that explanatory style for negative events may persist across the life span and may constitute an enduring risk factor for depression, low achievement, and physical illness.

Holistic life-span health outcomes among elite intercollegiate student-athletes.

PubMed

Sorenson, Shawn C; Romano, Russell; Scholefield, Robin M; Martin, Brandon E; Gordon, James E; Azen, Stanley P; Schroeder, E Todd; Salem, George J

2014-01-01

Competitive sports are recognized as having unique health benefits and risks, and the effect of sports on life-span health among elite athletes has received increasing attention. However, supporting scientific data are sparse and do not represent modern athletes. To assess holistic life-span health and health-related quality-of-life (HRQL) among current and former National Collegiate Athletic Association student-athletes (SAs). Cross-sectional study. A large Division I university. Population-based sample of 496 university students and alumni (age 17-84 years), including SAs and an age-matched and sex-matched nonathlete (NA) control group. Participants completed anonymous, self-report questionnaires. We measured the Short-Form 12 (SF-12) physical and mental component HRQL scores and cumulative lifetime experience and relative risk of treatment for joint, cardiopulmonary, and psychosocial health concerns. Older alumni (age 43+ years) SAs reported greater joint health concerns than NAs (larger joint summary scores; P = .04; Cohen d = 0.69; probability of clinically important difference [pCID] = 77%; treatment odds ratio [OR] = 14.0, 95% confidence interval [CI] = 1.6, 126). Joint health for current and younger alumni SAs was similar to that for NAs. Older alumni reported greater cardiopulmonary health concerns than younger alumni (summary score P < .001; d = 1.05; pCID = 85%; OR = 5.8, 95% CI = 2.0, 16) and current students (P < .001; d = 2.25; pCID >99.5%; OR = 7.1, 95% CI = 3.3, 15), but the risk was similar for SAs and NAs. Current SAs demonstrated evidence of better psychosocial health (summary score P = .006; d = -0.52; pCID = 40%) and mental component HRQL (P = .008; d = 0.50; pCID = 48%) versus NAs but similar psychosocial treatment odds (OR = 0.87, 95% CI = 0.39, 1.9). Psychosocial health and mental component HRQL were similar between alumni SAs and NAs. No differences were observed between SAs and NAs in physical component HRQL. The SAs demonstrated

The Writing Process: Effects of Life-Span Development on Imaging.

ERIC Educational Resources Information Center

Shock, Diane Hahn

A qualitative study focused on incubation and illumination within the act of writing to determine if life-span development affects image production during these creative, cognitive acts. Sixteen subjects of both sexes from four age groups represented major developmental stages in the life cycle. The research design provided two 90-minute sessions…

From menarche to menopause: the fertile life span of celiac women.

PubMed

Santonicola, Antonella; Iovino, Paola; Cappello, Carmelina; Capone, Pietro; Andreozzi, Paolo; Ciacci, Carolina

2011-10-01

We evaluated menopause-associated disorders and fertile life span in women with celiac disease (CD) under untreated conditions and after long-term treatment with a gluten-free diet. The participants were 33 women with CD after menopause (untreated CD group), 25 celiac women consuming a gluten-free diet at least 10 years before menopause (treated CD group), and 45 healthy volunteers (control group). The Menopause Rating Scale questionnaire was used to gather information on menopause-associated disorders. The International Physical Activity Questionnaire was used to acquire information on physical activity. Untreated celiac women had a shorter duration of fertile life span than did the control women because of an older age of menarche and a younger age of menopause (P < 0.01). The scores for hot flushes, muscle/joint problems, and irritability were higher in untreated celiac women than in the control women (higher by 49.4%, 121.4%, and 58.6%, respectively; P < 0.05). In comparison with untreated CD, long-lasting treatment of CD was not associated with a significant difference in the duration of fertile life span, but was only associated with a significant reduction in muscle/joint problems (a reduction of 47.1%; P < 0.05). Late menarche and early menopause causes a shorter fertile period in untreated celiac women compared with control women. A gluten-free diet that started at least 10 years before menopause prolongs the fertile life span of celiac women. The perception of intensity of hot flushes and irritability is more severe in untreated celiac women than in controls. Low physical exercise and/or poorer quality of life frequently reported by untreated celiac women might be the cause of reduced discomfort tolerance, thus increasing the subjective perception of menopausal symptoms.

Life-span development of self-esteem and its effects on important life outcomes.

PubMed

Orth, Ulrich; Robins, Richard W; Widaman, Keith F

2012-06-01

We examined the life-span development of self-esteem and tested whether self-esteem influences the development of important life outcomes, including relationship satisfaction, job satisfaction, occupational status, salary, positive and negative affect, depression, and physical health. Data came from the Longitudinal Study of Generations. Analyses were based on 5 assessments across a 12-year period of a sample of 1,824 individuals ages 16 to 97 years. First, growth curve analyses indicated that self-esteem increases from adolescence to middle adulthood, reaches a peak at about age 50 years, and then decreases in old age. Second, cross-lagged regression analyses indicated that self-esteem is best modeled as a cause rather than a consequence of life outcomes. Third, growth curve analyses, with self-esteem as a time-varying covariate, suggested that self-esteem has medium-sized effects on life-span trajectories of affect and depression, small to medium-sized effects on trajectories of relationship and job satisfaction, a very small effect on the trajectory of health, and no effect on the trajectory of occupational status. These findings replicated across 4 generations of participants--children, parents, grandparents, and their great-grandparents. Together, the results suggest that self-esteem has a significant prospective impact on real-world life experiences and that high and low self-esteem are not mere epiphenomena of success and failure in important life domains. 2012 APA, all rights reserved

A Holistic Model for Wellness and Prevention over the Life Span.

ERIC Educational Resources Information Center

Witmer, J. Melvin; Sweeney, Thomas J.

1992-01-01

Presents integrated paradigm for wellness and prevention over the life span for purpose of theory building, research, clinical application, education, advocacy, and consciousness raising. Model described includes 11 characteristics desirable for optimal health and functioning. Notes characteristics are expressed through five life tasks of…

The Social Context of Managing Diabetes across the Life Span

PubMed Central

Wiebe, Deborah J.; Helgeson, Vicki; Berg, Cynthia A.

2016-01-01

Diabetes self-management is crucial to maintaining quality of life and preventing long-term complications, and occurs daily in the context of close interpersonal relationships. This article examines how social relationships are central to meeting the complex demands of managing type 1 and type 2 diabetes across the life span. The social context of diabetes management includes multiple resources, including family (parents, spouses), peers, romantic partners, and health care providers. We discuss how these social resources change across the life span, focusing on childhood and adolescence, emerging adulthood, and adulthood and aging. We review how diabetes both affects and is affected by key social relationships at each developmental period. Despite high variability in how the social context is conceptualized and measured across studies, findings converge on the characteristics of social relationships that facilitate or undermine diabetes management across the life span. These characteristics are consistent with both Interpersonal Theory and Self-Determination Theory, two organizing frameworks that we utilize to explore social behaviors that are related to diabetes management. Involvement and support from one’s social partners, particularly family members, is consistently associated with good diabetes outcomes when characterized by warmth, collaboration and acceptance. Under-involvement and interactions characterized by conflict and criticism are consistently associated with poor diabetes outcomes. Intrusive involvement that contains elements of social control may undermine diabetes management, particularly when it impinges on self-efficacy. Implications for future research directions and for interventions that promote the effective use of the social context to improve diabetes self-management are discussed. PMID:27690482

Holistic Life-Span Health Outcomes Among Elite Intercollegiate Student–Athletes

PubMed Central

Sorenson, Shawn C.; Romano, Russell; Scholefield, Robin M.; Martin, Brandon E.; Gordon, James E.; Azen, Stanley P.; Schroeder, E. Todd; Salem, George J.

2014-01-01

Context: Competitive sports are recognized as having unique health benefits and risks, and the effect of sports on life-span health among elite athletes has received increasing attention. However, supporting scientific data are sparse and do not represent modern athletes. Objective: To assess holistic life-span health and health-related quality-of-life (HRQL) among current and former National Collegiate Athletic Association student–athletes (SAs). Design: Cross-sectional study. Setting: A large Division I university. Patients or Other Participants: Population-based sample of 496 university students and alumni (age 17–84 years), including SAs and an age-matched and sex-matched nonathlete (NA) control group. Main Outcome Measure(s): Participants completed anonymous, self-report questionnaires. We measured the Short-Form 12 (SF-12) physical and mental component HRQL scores and cumulative lifetime experience and relative risk of treatment for joint, cardiopulmonary, and psychosocial health concerns. Results: Older alumni (age 43+ years) SAs reported greater joint health concerns than NAs (larger joint summary scores; P = .04; Cohen d = 0.69; probability of clinically important difference [pCID] = 77%; treatment odds ratio [OR] = 14.0, 95% confidence interval [CI] = 1.6, 126). Joint health for current and younger alumni SAs was similar to that for NAs. Older alumni reported greater cardiopulmonary health concerns than younger alumni (summary score P < .001; d = 1.05; pCID = 85%; OR = 5.8, 95% CI = 2.0, 16) and current students (P < .001; d = 2.25; pCID >99.5%; OR = 7.1, 95% CI = 3.3, 15), but the risk was similar for SAs and NAs. Current SAs demonstrated evidence of better psychosocial health (summary score P = .006; d = −0.52; pCID = 40%) and mental component HRQL (P = .008; d = 0.50; pCID = 48%) versus NAs but similar psychosocial treatment odds (OR = 0.87, 95% CI = 0.39, 1.9). Psychosocial health and mental component HRQL were similar between alumni SAs and NAs

Health span approximates life span among many supercentenarians: compression of morbidity at the approximate limit of life span.

PubMed

Andersen, Stacy L; Sebastiani, Paola; Dworkis, Daniel A; Feldman, Lori; Perls, Thomas T

2012-04-01

We analyze the relationship between age of survival, morbidity, and disability among centenarians (age 100-104 years), semisupercentenarians (age 105-109 years), and supercentenarians (age 110-119 years). One hundred and four supercentenarians, 430 semisupercentenarians, 884 centenarians, 343 nonagenarians, and 436 controls were prospectively followed for an average of 3 years (range 0-13 years). The older the age group, generally, the later the onset of diseases, such as cancer, cardiovascular disease, dementia, and stroke, as well as of cognitive and functional decline. The hazard ratios for these individual diseases became progressively less with older and older age, and the relative period of time spent with disease was lower with increasing age group. We observed a progressive delay in the age of onset of physical and cognitive function impairment, age-related diseases, and overall morbidity with increasing age. As the limit of human life span was effectively approached with supercentenarians, compression of morbidity was generally observed.

Health Span Approximates Life Span Among Many Supercentenarians: Compression of Morbidity at the Approximate Limit of Life Span

PubMed Central

Andersen, Stacy L.; Sebastiani, Paola; Dworkis, Daniel A.; Feldman, Lori

2012-01-01

We analyze the relationship between age of survival, morbidity, and disability among centenarians (age 100–104 years), semisupercentenarians (age 105–109 years), and supercentenarians (age 110–119 years). One hundred and four supercentenarians, 430 semisupercentenarians, 884 centenarians, 343 nonagenarians, and 436 controls were prospectively followed for an average of 3 years (range 0–13 years). The older the age group, generally, the later the onset of diseases, such as cancer, cardiovascular disease, dementia, and stroke, as well as of cognitive and functional decline. The hazard ratios for these individual diseases became progressively less with older and older age, and the relative period of time spent with disease was lower with increasing age group. We observed a progressive delay in the age of onset of physical and cognitive function impairment, age-related diseases, and overall morbidity with increasing age. As the limit of human life span was effectively approached with supercentenarians, compression of morbidity was generally observed. PMID:22219514

Women's Spirituality across the Life Span: Implications for Counseling

ERIC Educational Resources Information Center

Briggs, Michele Kielty; Dixon, Andrea L.

2013-01-01

Women's spirituality has unique characteristics that are often ignored within the spirituality literature. The authors review the literature on women's spirituality to reveal the major themes women have identified as relevant to their spiritual journeys across the life span. Implications for counseling and ideas for practice are included after…

Increasing cell culture population doublings for long-term growth of finite life span human cell cultures

DOEpatents

Stampfer, Martha R.; Garbe, James C.

2016-06-28

Cell culture media formulations for culturing human epithelial cells are herein described. Also described are methods of increasing population doublings in a cell culture of finite life span human epithelial cells and prolonging the life span of human cell cultures. Using the cell culture media disclosed alone and in combination with addition to the cell culture of a compound associated with anti-stress activity achieves extended growth of pre-stasis cells and increased population doublings and life span in human epithelial cell cultures.

Increasing cell culture population doublings for long-term growth of finite life span human cell cultures

DOEpatents

Stampfer, Martha R; Garbe, James C

2015-02-24

Cell culture media formulations for culturing human epithelial cells are herein described. Also described are methods of increasing population doublings in a cell culture of finite life span human epithelial cells and prolonging the life span of human cell cultures. Using the cell culture media disclosed alone and in combination with addition to the cell culture of a compound associated with anti-stress activity achieves extended growth of pre-stasis cells and increased population doublings and life span in human epithelial cell cultures.

Mice Producing Reduced Levels of Insulin-Like Growth Factor Type 1 Display an Increase in Maximum, but not Mean, Life Span

PubMed Central

2014-01-01

Reduced signaling through the IGF type 1 (IGF-1) receptor increases life span in multiple invertebrate organisms. Studies on mammalian longevity suggest that reducing levels of IGF-1 may also increase life span. However, the data are conflicting and complicated by the physiology of the mammalian neuroendocrine system. We have performed life-span analysis on mice homozygous for an insertion in the Igf1 gene. These mice produce reduced levels of IGF-1 and display a phenotype consistent with a significant decrease in IGF-1. Life-span analysis was carried out at three independent locations. Although the life-span data varied between sites, the maximum life span of the IGF-1-deficient mice was significantly increased and age-specific mortality rates were reduced in the IGF-1-deficient mice; however, mean life span did not differ except at one site, where mean life span was increased in female IGF-1-deficient animals. Early life mortality was noted in one cohort of IGF-1-deficient mice. The results are consistent with a significant role for IGF-1 in the modulation of life span but contrast with the published life-span data for the hypopituitary Ames and Snell dwarf mice and growth hormone receptor null mice, indicating that a reduction in IGF-1 alone is insufficient to increase both mean and maximal life span in mice. PMID:23873963

Effect of habitat preference on frond life span in three Cyathea tree ferns

NASA Astrophysics Data System (ADS)

Chiu, Tzu Yun; Wang, Hsiang Hua; Lun Kuo, Yao; Kume, Tomonori

2013-04-01

It has been reported that plants living in various geographical areas had different physiological forms, as factors of microenvironment have strong impacts on physiological characters. However, the physiological characters of fronds have been scarcely reported in ferns. In this study, we investigated physiological differences in response to the habitat preference in the three tree ferns in northeast Taiwan, Cyathea lepifera, C. spinulosa, and C. podophylla, prefer to open site, edge of forest, and interior forest, respectively. The canopy openness above the individuals of C. lepifera, C. spinulosa and C. podophylla were 29.2 ± 14.10 , 7.0 ± 3.07 and 5.0 ± 2.24 %, respectively. Among three species, C. podophylla had the longest frond life span (13.0 ± 4.12 months) than the two others (C. lepifera (6.8 ± 1.29 months) and C. spinulosa (7.3 ±1.35 months). Our result supported the general patterns that shade intolerant species have a shorter leaf life span than shade tolerant species. The maximum net CO2 assimilation of C. lepifera, C. spinulosa and C. podophylla were 11.46 ± 1.34, 8.27 ± 0.69, and 6.34 ± 0.54 μmol CO2 m-2 s-1, respectively. As well, C. lepifera had the highest photosynthetic light saturation point (LSP), while C. podophylla had the lowest LSP among these three tree ferns. These suggested that C. lepifera could be more efficient for capturing and utilizing light resources under the larger canopy openness condition than the other two species. We also found that frond C : N ratio were positively correlated with frond life span among species. C. podophylla, with the longest frond life span, had the highest frond C : N ratio (22.17 ± 1.95), which was followed by C. spinulosa (18.58 ± 1.37) and C. lepifera (18.68 ± 2.63) with shorter frond life span. The results were consistent to the theory that the fronds and leaves of shade intolerant species have high photosynthetic abilities with low C : N ratio. Key words: Canopy openness, frond life span

Getting Together: Social Contact Frequency across the Life Span

ERIC Educational Resources Information Center

Sander, Julia; Schupp, Jürgen; Richter, David

2017-01-01

Frequent social interactions are strongly linked to positive affect, longevity, and good health. Although there has been extensive research on changes in the size of social networks over time, little attention has been given to the development of contact frequency across the life span. In this cohort-sequential longitudinal study, we examined…

Reproductive adaptation in Drosophila exposed to oxygen-enriched atmospheres

NASA Technical Reports Server (NTRS)

Kloek, G.; Winkle, L.

1979-01-01

Ten successive generations of a Drosophila melanogaster population were exposed to an atmospheric mix of 50% oxygen/50% nitrogen at standard pressure. This atmospheric mix has been shown to be toxic to this species and causes significantly shortened life span. By the fifth generation, survivorship and life span for the first 25-30 days were identical to control populations and total life span was shorter by only a few days. Egg-laying rates were stable in the experimental populations but below those of the controls. Hatching success was identical between experimental and control populations. Even though the egg-laying rates were lower in 50% oxygen, it was concluded that the population had adapted and could maintain a stable population in these conditions. The near-normal life spans, normal hatching rates, and overall population stability, exhibited following five generations of adaptation, were considered sufficient to allow continued reproduction in spite of a reduced egg-laying rate.

Reproductive adaptation in Drosophila exposed to oxygen-enriched atmospheres.

PubMed

Kloek, G; Winkle, L

1979-04-01

Ten successive generations of a Drosophila melanogaster population were exposed to an atmospheric mix of 50% oxygen/50% nitrogen at standard pressure. This atmospheric mix has been shown to be toxic to this species and causes significantly shortened life span. By the fifth generation, survivorship and life span for the first 25-30 days were identical to control populations and total life span was shorter by only a few days. Egg-laying rates were stable in the experimental populations but below those of the controls. Hatching success was identical between experimental and control populations. Even though the egg-laying rates were lower in 50% oxygen, it was concluded that the population had adapted and could maintain a stable population in these conditions. The near-normal life spans, normal hatching rates, and overall population stability, exhibited following five generations of adaptation, were considered sufficient to allow continued reproduction in spite of a reduced egg-laying rate.

Foraging across the life span: is there a reduction in exploration with aging?

PubMed Central

Mata, Rui; Wilke, Andreas; Czienskowski, Uwe

2013-01-01

Does foraging change across the life span, and in particular, with aging? We report data from two foraging tasks used to investigate age differences in search in external environments as well as internal search in memory. Overall, the evidence suggests that foraging behavior may undergo significant changes across the life span across internal and external search. In particular, we find evidence of a trend toward reduced exploration with increased age. We discuss these findings in light of theories that postulate a link between aging and reductions in novelty seeking and exploratory behavior. PMID:23616741

From Children to Adults: Motor Performance across the Life-Span

PubMed Central

Leversen, Jonas S. R.; Haga, Monika; Sigmundsson, Hermundur

2012-01-01

The life-span approach to development provides a theoretical framework to examine the general principles of life-long development. This study aims to investigate motor performance across the life span. It also aims to investigate if the correlations between motor tasks increase with aging. A cross-sectional design was used to describe the effects of aging on motor performance across age groups representing individuals from childhood to young adult to old age. Five different motor tasks were used to study changes in motor performance within 338 participants (7–79 yrs). Results showed that motor performance increases from childhood (7–9) to young adulthood (19–25) and decreases from young adulthood (19–25) to old age (66–80). These results are mirroring results from cognitive research. Correlation increased with increasing age between two fine motor tasks and two gross motor tasks. We suggest that the findings might be explained, in part, by the structural changes that have been reported to occur in the developing and aging brain and that the theory of Neural Darwinism can be used as a framework to explain why these changes occur. PMID:22719958

Neuromodulation of Behavioral and Cognitive Development across the Life Span

ERIC Educational Resources Information Center

Li, Shu-Chen

2012-01-01

Among other mechanisms, behavioral and cognitive development entail, on the one hand, contextual scaffolding and, on the other hand, neuromodulation of adaptive neurocognitive representations across the life span. Key brain networks underlying cognition, emotion, and motivation are innervated by major transmitter systems (e.g., the catecholamines…

Slow life histories in lizards living in the highlands of the Andes Mountains.

PubMed

Boretto, Jorgelina M; Cabezas-Cartes, Facundo; Ibargüengoytía, Nora R

2018-05-01

In the highlands of the Andes, lizards must balance precisely the allocation of energy for growth and reproduction to ensure their survival. We studied the individuals' age, growth rates, age at sexual maturity, and maximum life span of the viviparous lizard Phymaturus antofagastensis, endemic of cold and harsh environments at high altitudes in the Andes Mountains of Catamarca province, Argentina. We also estimated key life history parameters like reproductive effort, lifetime reproductive effort, net reproductive rate, and relative reproductive time in P. antofagastensis as well as in other Phymaturus to compare the interplay among growth, maintenance, and reproduction in species that live across a latitudinal and altitudinal gradient. We found that females and males of P. antofagastensis mature late in life, at 6-7 years old, respectively, and some individuals reached 20 years of age. Adult females showed higher specific growth rates than males and an adult life span of 9 years which, due to their biennial reproduction, results in an estimated production of only four litters in life. This species exhibits one of the highest lifetime reproductive efforts described for lizards. Our results indicate the existence of a tradeoff between the number of reproductive events throughout life and reproductive effort devoted to each event in Phymaturus, related to the phylogenetic group. The palluma group shows low reproductive effort but high number of reproductive events throughout their lives, whereas the patagonicus group shows high reproductive efforts in low number of reproductive events.

Early-life nutritional effects on the female reproductive system.

PubMed

Chan, K A; Tsoulis, M W; Sloboda, D M

2015-02-01

There is now considerable epidemiological and experimental evidence indicating that early-life environmental conditions, including nutrition, affect subsequent development in later life. These conditions induce highly integrated responses in endocrine-related homeostasis, resulting in persistent changes in the developmental trajectory producing an altered adult phenotype. Early-life events trigger processes that prepare the individual for particular circumstances that are anticipated in the postnatal environment. However, where the intrauterine and postnatal environments differ markedly, such modifications to the developmental trajectory may prove maladaptive in later life. Reproductive maturation and function are similarly influenced by early-life events. This should not be surprising, because the primordial follicle pool is established early in life and is thus vulnerable to early-life events. Results of clinical and experimental studies have indicated that early-life adversity is associated with a decline in ovarian follicular reserve, changes in ovulation rates, and altered age at onset of puberty. However, the underlying mechanisms regulating the relationship between the early-life developmental environment and postnatal reproductive development and function are unclear. This review examines the evidence linking early-life nutrition and effects on the female reproductive system, bringing together clinical observations in humans and experimental data from targeted animal models. © 2015 Society for Endocrinology.

Redesign of a Life Span Development Course Using Fink's Taxonomy

ERIC Educational Resources Information Center

Fallahi, Carolyn R.

2008-01-01

This study compared a traditional lecture-based life span development course to the same course redesigned using Fink's (2003) taxonomy of significant learning. The goals, activities, and feedback within the course corresponded to Fink's 6 taxa (knowledge, application, integration, human dimension, caring, learning how to learn). Undergraduates in…

Target of Rapamycin Signaling Regulates Metabolism, Growth, and Life Span in Arabidopsis[W][OA

PubMed Central

Ren, Maozhi; Venglat, Prakash; Qiu, Shuqing; Feng, Li; Cao, Yongguo; Wang, Edwin; Xiang, Daoquan; Wang, Jinghe; Alexander, Danny; Chalivendra, Subbaiah; Logan, David; Mattoo, Autar; Selvaraj, Gopalan; Datla, Raju

2012-01-01

Target of Rapamycin (TOR) is a major nutrition and energy sensor that regulates growth and life span in yeast and animals. In plants, growth and life span are intertwined not only with nutrient acquisition from the soil and nutrition generation via photosynthesis but also with their unique modes of development and differentiation. How TOR functions in these processes has not yet been determined. To gain further insights, rapamycin-sensitive transgenic Arabidopsis thaliana lines (BP12) expressing yeast FK506 Binding Protein12 were developed. Inhibition of TOR in BP12 plants by rapamycin resulted in slower overall root, leaf, and shoot growth and development leading to poor nutrient uptake and light energy utilization. Experimental limitation of nutrient availability and light energy supply in wild-type Arabidopsis produced phenotypes observed with TOR knockdown plants, indicating a link between TOR signaling and nutrition/light energy status. Genetic and physiological studies together with RNA sequencing and metabolite analysis of TOR-suppressed lines revealed that TOR regulates development and life span in Arabidopsis by restructuring cell growth, carbon and nitrogen metabolism, gene expression, and rRNA and protein synthesis. Gain- and loss-of-function Ribosomal Protein S6 (RPS6) mutants additionally show that TOR function involves RPS6-mediated nutrition and light-dependent growth and life span in Arabidopsis. PMID:23275579

Like cognitive function, decision making across the life span shows profound age-related changes.

PubMed

Tymula, Agnieszka; Rosenberg Belmaker, Lior A; Ruderman, Lital; Glimcher, Paul W; Levy, Ifat

2013-10-15

It has long been known that human cognitive function improves through young adulthood and then declines across the later life span. Here we examined how decision-making function changes across the life span by measuring risk and ambiguity attitudes in the gain and loss domains, as well as choice consistency, in an urban cohort ranging in age from 12 to 90 y. We identified several important age-related patterns in decision making under uncertainty: First, we found that healthy elders between the ages of 65 and 90 were strikingly inconsistent in their choices compared with younger subjects. Just as elders show profound declines in cognitive function, they also show profound declines in choice rationality compared with their younger peers. Second, we found that the widely documented phenomenon of ambiguity aversion is specific to the gain domain and does not occur in the loss domain, except for a slight effect in older adults. Finally, extending an earlier report by our group, we found that risk attitudes across the life span show an inverted U-shaped function; both elders and adolescents are more risk-averse than their midlife counterparts. Taken together, these characterizations of decision-making function across the life span in this urban cohort strengthen the conclusions of previous reports suggesting a profound impact of aging on cognitive function in this domain.

Endosomal protein sorting and autophagy genes contribute to the regulation of yeast life span.

PubMed

Longo, Valter D; Nislow, Corey; Fabrizio, Paola

2010-11-01

Accumulating evidence from various organisms points to a role for autophagy in the regulation of life span. By performing a genome-wide screen to identify novel life span determinants in Saccharomyces cerevisiae, we have obtained further insights into the autophagy-related and -unrelated degradation processes that may be important for preventing cellular senescence. The generation of multivesicular bodies and their fusion with the vacuole in the endosomal pathway emerged as novel cell functions involved in yeast chronological survival and longevity extension.

"Pull and push back" concepts of longevity and life span extension.

PubMed

Muradian, Khachik

2013-12-01

The negative relation between metabolism and life span is a fundamental gerontological discovery well documented in a variety of ontogenetic and phylogenetic models. But how the long-lived species and populations sustain lower metabolic rate and, in more general terms, what is the efficient way to decline the metabolism? The suggested 'pull and push back' hypothesis assumes that decreased Po2 (hypoxia) and/or increased [Formula: see text] (hypercapnia) may create preconditions for the declined metabolic and aging rates. However, wider implementation of such ideas is compromised because of little advances in modification of the metabolic rate. Artificial atmosphere with controlled [Formula: see text] and [Formula: see text] could be a promising approach because of the minimal external invasions and involvement of the backward and forward loops ensuring physiological self-regulation of the metabolic perturbations. General considerations and existing data indicate that manipulations of [Formula: see text] may be more efficient in life span extension than [Formula: see text]. Thus, maximum life span of mammals positively correlates with the blood [Formula: see text] and HCO3 (-) but not with [Formula: see text]. Yet, proportional decease of the body [Formula: see text] and increase of [Formula: see text] seems the most optimal regime ensuring lower losses of the energy equivalents. Furthermore, especially rewarding results could be expected when such changes are modeled without major external invasions using the animals' inner capacity to consume O2 and generate CO2, as it is typical for the extreme longevity.

Reading through the Life Span: Individual Differences in Psycholinguistic Effects

ERIC Educational Resources Information Center

Davies, Rob A. I.; Arnell, Ruth; Birchenough, Julia M. H.; Grimmond, Debbie; Houlson, Sam

2017-01-01

The effects of psycholinguistic variables are critical to the evaluation of theories about the cognitive reading system. However, reading research has tended to focus on the impact of key variables on average performance. We report the first investigation examining variation in psycholinguistic effects across the life span, from childhood into old…

Metabotypes with properly functioning mitochondria and anti-inflammation predict extended productive life span in dairy cows

PubMed Central

Huber, K.; Dänicke, S.; Rehage, J.; Sauerwein, H.; Otto, W.; Rolle-Kampczyk, U.; von Bergen, M.

2016-01-01

The failure to adapt metabolism to the homeorhetic demands of lactation is considered as a main factor in reducing the productive life span of dairy cows. The so far defined markers of production performance and metabolic health in dairy cows do not predict the length of productive life span satisfyingly. This study aimed to identify novel pathways and biomarkers related to productive life in dairy cows by means of (targeted) metabolomics. In a longitudinal study from 42 days before up to 100 days after parturition, we identified metabolites such as long-chain acylcarnitines and biogenic amines associated with extended productive life spans. These metabolites are mainly secreted by the liver and depend on the functionality of hepatic mitochondria. The concentrations of biogenic amines and some acylcarnitines differed already before the onset of lactation thus indicating their predictive potential for continuation or early ending of productive life. PMID:27089826

Metabotypes with properly functioning mitochondria and anti-inflammation predict extended productive life span in dairy cows.

PubMed

Huber, K; Dänicke, S; Rehage, J; Sauerwein, H; Otto, W; Rolle-Kampczyk, U; von Bergen, M

2016-04-19

The failure to adapt metabolism to the homeorhetic demands of lactation is considered as a main factor in reducing the productive life span of dairy cows. The so far defined markers of production performance and metabolic health in dairy cows do not predict the length of productive life span satisfyingly. This study aimed to identify novel pathways and biomarkers related to productive life in dairy cows by means of (targeted) metabolomics. In a longitudinal study from 42 days before up to 100 days after parturition, we identified metabolites such as long-chain acylcarnitines and biogenic amines associated with extended productive life spans. These metabolites are mainly secreted by the liver and depend on the functionality of hepatic mitochondria. The concentrations of biogenic amines and some acylcarnitines differed already before the onset of lactation thus indicating their predictive potential for continuation or early ending of productive life.

Sustained Attention Across the Life Span in a Sample of 10,000: Dissociating Ability and Strategy.

PubMed

Fortenbaugh, Francesca C; DeGutis, Joseph; Germine, Laura; Wilmer, Jeremy B; Grosso, Mallory; Russo, Kathryn; Esterman, Michael

2015-09-01

Normal and abnormal differences in sustained visual attention have long been of interest to scientists, educators, and clinicians. Still lacking, however, is a clear understanding of how sustained visual attention varies across the broad sweep of the human life span. In the present study, we filled this gap in two ways. First, using an unprecedentedly large 10,430-person sample, we modeled age-related differences with substantially greater precision than have prior efforts. Second, using the recently developed gradual-onset continuous performance test (gradCPT), we parsed sustained-attention performance over the life span into its ability and strategy components. We found that after the age of 15 years, the strategy and ability trajectories saliently diverge. Strategy becomes monotonically more conservative with age, whereas ability peaks in the early 40s and is followed by a gradual decline in older adults. These observed life-span trajectories for sustained attention are distinct from results of other life-span studies focusing on fluid and crystallized intelligence. © The Author(s) 2015.

The importance of adult life-span perspective in explaining variations in political ideology.

PubMed

Sedek, Grzegorz; Kossowska, Malgorzata; Rydzewska, Klara

2014-06-01

As a comment on Hibbing et al.'s paper, we discuss the evolution of political and social views from more liberal to more conservative over the span of adulthood. We show that Hibbing et al.'s theoretical model creates a false prediction from this developmental perspective, as increased conservatism in the adult life-span trajectory is accompanied by the avoidance of negative bias.

Human evolution, life history theory, and the end of biological reproduction.

PubMed

Last, Cadell

2014-01-01

Throughout primate history there have been three major life history transitions towards increasingly delayed sexual maturation and biological reproduction, as well as towards extended life expectancy. Monkeys reproduce later and live longer than do prosimians, apes reproduce later and live longer than do monkeys, and humans reproduce later and live longer than do apes. These life history transitions are connected to increased encephalization. During the last life history transition from apes to humans, increased encephalization co-evolved with increased dependence on cultural knowledge for energy acquisition. This led to a dramatic pressure for more energy investment in growth over current biological reproduction. Since the industrial revolution socioeconomic development has led to even more energy being devoted to growth over current biological reproduction. I propose that this is the beginning of an ongoing fourth major primate life history transition towards completely delayed biological reproduction and an extension of the evolved human life expectancy. I argue that the only fundamental difference between this primate life history transition and previous life history transitions is that this transition is being driven solely by cultural evolution, which may suggest some deeper evolutionary transition away from biological evolution is already in the process of occurring.

Age Differences in Five Personality Domains across the Life Span

ERIC Educational Resources Information Center

Allemand, Mathias; Zimprich, Daniel; Hendriks, A. A. Jolijn

2008-01-01

The present study addresses the issue of age differences in 5 personality domains across the life span in a cross-sectional study. In contrast to most previous studies, the present study follows a methodologically more rigorous approach to warrant that age-related differences in personality structure and mean level can be meaningfully compared. It…

Prenatal programming of neuroendocrine reproductive function.

PubMed

Evans, Neil P; Bellingham, Michelle; Robinson, Jane E

2016-07-01

It is now well recognized that the gestational environment can have long-lasting effects not only on the life span and health span of an individual but also, through potential epigenetic changes, on future generations. This article reviews the "prenatal programming" of the neuroendocrine systems that regulate reproduction, with a specific focus on the lessons learned using ovine models. The review examines the critical roles played by steroids in normal reproductive development before considering the effects of prenatal exposure to exogenous steroid hormones including androgens and estrogens, the effects of maternal nutrition and stress during gestation, and the effects of exogenous chemicals such as alcohol and environment chemicals. In so doing, it becomes evident that, to maximize fitness, the regulation of reproduction has evolved to be responsive to many different internal and external cues and that the GnRH neurosecretory system expresses a degree of plasticity throughout life. During fetal life, however, the system is particularly sensitive to change and at this time, the GnRH neurosecretory system can be "shaped" both to achieve normal sexually differentiated function but also in ways that may adversely affect or even prevent "normal function". The exact mechanisms through which these programmed changes are brought about remain largely uncharacterized but are likely to differ depending on the factor, the timing of exposure to that factor, and the species. It would appear, however, that some afferent systems to the GnRH neurons such as kisspeptin, may be critical in this regard as it would appear to be sensitive to a wide variety of factors that can program reproductive function. Finally, it has been noted that the prenatal programming of neuroendocrine reproductive function can be associated with epigenetic changes, which would suggest that in addition to direct effects on the exposed offspring, prenatal programming could have transgenerational effects on

Grandmothering and cognitive resources are required for the emergence of menopause and extensive post-reproductive lifespan.

PubMed

Aimé, Carla; André, Jean-Baptiste; Raymond, Michel

2017-07-01

Menopause, the permanent cessation of ovulation, occurs in humans well before the end of the expected lifespan, leading to an extensive post-reproductive period which remains a puzzle for evolutionary biologists. All human populations display this particularity; thus, it is difficult to empirically evaluate the conditions for its emergence. In this study, we used artificial neural networks to model the emergence and evolution of allocation decisions related to reproduction in simulated populations. When allocation decisions were allowed to freely evolve, both menopause and extensive post-reproductive life-span emerged under some ecological conditions. This result allowed us to test various hypotheses about the required conditions for the emergence of menopause and extensive post-reproductive life-span. Our findings did not support the Maternal Hypothesis (menopause has evolved to avoid the risk of dying in childbirth, which is higher in older women). In contrast, results supported a shared prediction from the Grandmother Hypothesis and the Embodied Capital Model. Indeed, we found that extensive post-reproductive lifespan allows resource reallocation to increase fertility of the children and survival of the grandchildren. Furthermore, neural capital development and the skill intensiveness of the foraging niche, rather than strength, played a major role in shaping the age profile of somatic and cognitive senescence in our simulated populations. This result supports the Embodied Capital Model rather than the Grand-Mother Hypothesis. Finally, in simulated populations where menopause had already evolved, we found that reduced post-reproductive lifespan lead to reduced children's fertility and grandchildren's survival. The results are discussed in the context of the evolutionary emergence of menopause and extensive post-reproductive life-span.

Evolution of monogamy, paternal investment, and female life history in Peromyscus.

PubMed

Jašarević, Eldin; Bailey, Drew H; Crossland, Janet P; Dawson, Wallace D; Szalai, Gabor; Ellersieck, Mark R; Rosenfeld, Cheryl S; Geary, David C

2013-02-01

The timing of reproductive development and associated trade-offs in quantity versus quality of offspring produced across the life span are well documented in a wide range of species. The relation of these aspects of maternal life history to monogamy and paternal investment in offspring is not well studied in mammals, due in part to the rarity of the latter. By using five large, captive-bred populations of Peromyscus species that range from promiscuous mating with little paternal investment (P. maniculatus bairdii) to social and genetic monogamy with substantial paternal investment (P. californicus insignis), we modeled the interaction between monogamy and female life history. Monogamy and high paternal investment were associated with smaller litter size, delayed maternal reproduction that extended over a longer reproductive life span, and larger, higher quality offspring. The results suggest monogamy and paternal investment can alter the evolution of female life-history trajectories in mammals. PsycINFO Database Record (c) 2013 APA, all rights reserved

Deterioration, death and the evolution of reproductive restraint in late life.

PubMed

McNamara, John M; Houston, Alasdair I; Barta, Zoltan; Scheuerlein, Alexander; Fromhage, Lutz

2009-11-22

Explaining why organisms schedule reproduction over their lifetimes in the various ways that they do is an enduring challenge in biology. An influential theoretical prediction states that organisms should increasingly invest in reproduction as they approach the end of their life. An apparent mismatch of empirical data with this prediction has been attributed to age-related constraints on the ability to reproduce. Here we present a general framework for the evolution of age-related reproductive trajectories. Instead of characterizing an organism by its age, we characterize it by its physiological condition. We develop a common currency that if maximized at each time guarantees the whole life history is optimal. This currency integrates reproduction, mortality and changes in condition. We predict that under broad conditions it will be optimal for organisms to invest less in reproduction as they age, thus challenging traditional interpretations of age-related traits and renewing debate about the extent to which observed life histories are shaped by constraint versus adaptation. Our analysis gives a striking illustration of the differences between an age-based and a condition-based approach to life-history theory. It also provides a unified account of not only standard life-history models but of related models involving the allocation of limited resources.

Leaf life span and the mobility of "non-mobile" mineral nutrients - the case of boron in conifers

Treesearch

Pedro J. Aphalo; Anna W. Schoettle; Tarja Lehto

2002-01-01

Nutrient conservation is considered important for the adaptation of plants to infertile environments. The importance of leaf life spans in controlling mean residence time of nutrients in plants has usually been analyzed in relation to nutrients that can be retranslocated within the plant. Longer leaf life spans increase the mean residence time of all mineral...

Weight concern across the life-span: relationship to self-esteem and feminist identity.

PubMed

Tiggemann, M; Stevens, C

1999-07-01

The aim of this study was to investigate the correlates of weight concern across the life-span. Questionnaires assessing weight concern, self-esteem, and feminist attitudes were completed in their homes by 180 women aged between 18 and 60 years. It was found that there was a negative relationship between weight concern and self-esteem for 30 to 49-year-old women, but not for younger or older women. A similar pattern held for feminist attitudes. Among 30 to 49-year-old women, a strong feminist orientation related to a lesser concern with weight. It was concluded that the meaning and experience of body weight and size change across the life-span.

Life-history tradeoffs and reproductive cycles in Spotted Owls

USGS Publications Warehouse

Stoelting, Ricka E.; Gutierrez, R.J.; Kendall, William L.; Peery, M. Zachariah

2015-01-01

The study of tradeoffs among life-history traits has long been key to understanding the evolution of life-history strategies. However, more recently, evolutionary ecologists have realized that reproductive costs have the potential to influence population dynamics. Here, we tested for costs of reproduction in the California Spotted Owl (Strix occidentalis occidentalis), and assessed whether costs of reproduction in year t − 1 on reproduction in year t could be responsible for regionally synchronized biennial cycles in reproductive output. Logistic regression analysis and multistate mark–recapture models with state uncertainty revealed that breeding reduced the likelihood of reproducing in the subsequent year by 16% to 38%, but had no influence on subsequent survival. We also found that costs of reproduction in year t − 1 were correlated with climatic conditions in year t, with evidence of higher costs during the dry phase of the El Niño–Southern Oscillation. Using a simulation-based population model, we showed that strong reproductive costs had the potential to create biennial cycles in population-level reproductive output; however, estimated costs of reproduction appeared to be too small to explain patterns observed in Spotted Owls. In the absence of strong reproductive costs, we hypothesize that observed natural cycles in the reproductive output of Spotted Owls are related to as-yet-unmeasured, regionally concordant fluctuations in environmental conditions or prey resources. Despite theoretical evidence for demographic effects, our analyses illustrate that linking tradeoffs to actual changes in population processes will be challenging because of the potential confounding effects of individual and environmental variation.

Life-Span Extension in Mice by Preweaning Food Restriction and by Methionine Restriction in Middle Age

PubMed Central

Sun, Liou; Sadighi Akha, Amir A.; Miller, Richard A.

2009-01-01

Life span can be extended in rodents by restricting food availability (caloric restriction [CR]) or by providing food low in methionine (Meth-R). Here, we show that a period of food restriction limited to the first 20 days of life, via a 50% enlargement of litter size, shows extended median and maximal life span relative to mice from normal sized litters and that a Meth-R diet initiated at 12 months of age also significantly increases longevity. Furthermore, mice exposed to a CR diet show changes in liver messenger RNA patterns, in phosphorylation of Erk, Jnk2, and p38 kinases, and in phosphorylation of mammalian target of rapamycin and its substrate 4EBP1, HE-binding protein 1 that are not observed in liver from age-matched Meth-R mice. These results introduce new protocols that can increase maximal life span and suggest that the spectrum of metabolic changes induced by low-calorie and low-methionine diets may differ in instructive ways. PMID:19414512

Reproductive life of Bhoksa women.

PubMed

Garg, S K; Tyagi, D; Sankhyan, A R

1981-01-01

The paper discusses the reproductive life of 111 ever-married Bhoksa women. The mean age at marriage for women of all ages among Bhoksas, like other tribal populations, is high, unlike the caste populations. The mean ages at first birth of the pooled sample and of the completed fertility cases suggest late and early marriages of the older and younger generations. The maximum number of marriages occur between 15 and 19 years and of first births between 16 and 20 years. Percentage of reproductive wastage is high in both the lower and higher age groups. Young mothers with low birth orders and older mothers with high birth orders display a high frequency of reproductive wastage. Evidently, both birth order and the age of the mother have effects on reproductive wastage. Average number of children ever born (including stillbirth but not abortion or miscarriage) per mother of all ages is the highest among Bhoksas of all the studied ethnic groups of India. The Bhoksa, like caste populations, show a high number of children ever born per mother of completed fertility. Quite a high masculinity in the secondary sex ratio, like other mongoloid population is noticed. The contribution of mortality component to the Total Index of Opportunity for Selection is more than that of the fertility component. Bhoksas conform to the general low range of net reproductive index, which is however greater than unity, suggesting that they are in a growth stage.

A stockpile of ova in the grass frog Rana temporaria is established once for the life span. Do ovaries in amphibians and in mammals follow the same evolutionary strategy?

PubMed

Ogielska, Maria; Kotusz, Agnieszka; Augustyńska, Renata; Ihnatowicz, Jerzy; Paśko, Łukasz

2013-04-01

Most anuran amphibians produce high numbers of eggs during several consecutive breeding seasons. The question is still open whether oocytes are formed anew as a result of oogonial proliferation after each spawning or the definitive pool of oocytes is established during the juvenile period and is sufficient for the whole reproductive life span of a female. Our quantitative studies show that primary oogonia in adult female frogs can proliferate, but they fail to differentiate further and do not enter meiosis, and thereby there is no supplementation of new generations of oocytes after each spawning. Ovaries of one-year-old grass frogs contain (median) 53,447 diplotene oocytes, in two-years-old frogs this number decreased to 33,583 and eventually reached 25,679 in virgin mature females. More than 50% decrease in the total oocyte number was accompanied by massive degeneration (atresia) of oocytes. The final number of oocytes in a female forms a stock for 11-12 breeding seasons and exceeds the number of eggs produced during the potential reproductive life span of this species. The phylogenetic context of oocyte recruitment modes in the major clades of vertebrates is discussed in respect to their ability to replenish the stock (a renewable stock in ovaries named "open" vs. a non-renewable stock in ovaries named "closed"). Copyright © 2013 Wiley Periodicals, Inc.

Psychosocial stressors and the short life spans of legendary jazz musicians.

PubMed

Patalano, F

2000-04-01

Mean age at death of 168 legendary jazz musicians and 100 renowned classical musicians were compared to examine whether psychosocial stressors such as severe substance abuse, haphazard working conditions, lack of acceptance of jazz as an art form in the United States, marital and family discord, and a vagabond life style may have contributed to shortened life spans for the jazz musicians. Analysis indicated that the jazz musicians died at an earlier age (57.2 yr.) than the classical musicians (73.3 yr.).

The life span-prolonging effect of sirtuin-1 is mediated by autophagy.

PubMed

Morselli, Eugenia; Maiuri, Maria Chiara; Markaki, Maria; Megalou, Evgenia; Pasparaki, Angela; Palikaras, Konstantinos; Criollo, Alfredo; Galluzzi, Lorenzo; Malik, Shoaib Ahmad; Vitale, Ilio; Michaud, Mickael; Madeo, Frank; Tavernarakis, Nektarios; Kroemer, Guido

2010-01-01

The life span of various model organisms can be extended by caloric restriction as well as by autophagy-inducing pharmacological agents. Life span-prolonging effects have also been observed in yeast cells, nematodes and flies upon the overexpression of the deacetylase Sirtuin-1. Intrigued by these observations and by the established link between caloric restriction and Sirtuin-1 activation, we decided to investigate the putative implication of Sirtuin-1 in the response of human cancer cells and Caenorhabditis elegans to multiple triggers of autophagy. Our data indicate that the activation of Sirtuin-1 (by the pharmacological agent resveratrol and/or genetic means) per se ignites autophagy, and that Sirtuin-1 is required for the autophagic response to nutrient deprivation, in both human and nematode cells, but not for autophagy triggered by downstream signals such as the inhibition of mTOR or p53. Since the life spanextending effects of Sirtuin-1 activators are lost in autophagy-deficient C. elegans, our results suggest that caloric restriction and resveratrol extend longevity, at least in experimental settings, by activating autophagy.

Influence of Domain Knowledge on Monitoring Performance across the Life Span

ERIC Educational Resources Information Center

Löffler, Elisabeth; von der Linden, Nicole; Schneider, Wolfgang

2016-01-01

Two studies were conducted to investigate effects of domain knowledge on metacognitive monitoring across the life span in materials of different complexity. Participants from 4 age groups (3rd-grade children, adolescents, younger and older adults) were compared using an expert-novice paradigm. In Study 1, soccer experts' and novices'…

Herbivore-mediated ecological costs of reproduction shape the life history of an iteroparous plant.

PubMed

Miller, Tom E X; Tenhumberg, Brigitte; Louda, Svata M

2008-02-01

Plant reproduction yields immediate fitness benefits but can be costly in terms of survival, growth, and future fecundity. Life-history theory posits that reproductive strategies are shaped by trade-offs between current and future fitness that result from these direct costs of reproduction. Plant reproduction may also incur indirect ecological costs if it increases susceptibility to herbivores. Yet ecological costs of reproduction have received little empirical attention and remain poorly integrated into life-history theory. Here, we provide evidence for herbivore-mediated ecological costs of reproduction, and we develop theory to examine how these costs influence plant life-history strategies. Field experiments with an iteroparous cactus (Opuntia imbricata) indicated that greater reproductive effort (proportion of meristems allocated to reproduction) led to greater attack by a cactus-feeding insect (Narnia pallidicornis) and that damage by this herbivore reduced reproductive success. A dynamic programming model predicted strongly divergent optimal reproductive strategies when ecological costs were included, compared with when these costs were ignored. Meristem allocation by cacti in the field matched the optimal strategy expected under ecological costs of reproduction. The results indicate that plant reproductive allocation can strongly influence the intensity of interactions with herbivores and that associated ecological costs can play an important selective role in the evolution of plant life histories.

Demography of Genotypes: Failure of the Limited Life-Span Paradigm in Drosophila melanogaster

NASA Astrophysics Data System (ADS)

Curtsinger, James W.; Fukui, Hidenori H.; Townsend, David R.; Vaupel, James W.

1992-10-01

Experimental systems that are amenable to genetic manipulation can be used to address fundamental questions about genetic and nongenetic determinants of longevity. Analysis of large cohorts of ten genotypes of Drosophila melanogaster raised under conditions that favored extended survival has revealed variation between genotypes in both the slope and location of age-specific mortality curves. More detailed examination of a single genotype showed that the mortality trajectory was best fit by a two-stage Gompertz model, with no age-specific increase in mortality rates beyond 30 days after emergence. These results are contrary to the limited life-span paradigm, which postulates well-defined, genotype-specific limits on life-span and brief periods of intense and rapidly accelerating mortality rates at the oldest ages.

Life-Span Differences in the Uses and Gratifications of Tablets: Implications for Older Adults

PubMed Central

Magsamen-Conrad, Kate; Dowd, John; Abuljadail, Mohammad; Alsulaiman, Saud; Shareefi, Adnan

2015-01-01

This study extends Uses and Gratifications theory by examining the uses and gratifications of a new technological device, the tablet computer, and investigating the differential uses and gratifications of tablet computers across the life-span. First, we utilized a six-week tablet training intervention to adapt and extend existing measures to the tablet as a technological device. Next, we used paper-based and online surveys (N=847), we confirmed four main uses of tablets: 1) Information Seeking, 2) Relationship Maintenance, 3) Style, 4) Amusement and Killing time, and added one additional use category 5) Organization. We discovered differences among the five main uses of tablets across the life-span, with older adults using tablets the least overall. Builders, Boomers, GenX and GenY all reported the highest means for information seeking. Finally, we used a structural equation model to examine how uses and gratifications predicts hours of tablet use. The study provides limitations and suggestions for future research and marketers. In particular, this study offers insight to the relevancy of theory as it applies to particular information and communication technologies and consideration of how different periods in the life-span affect tablet motivations. PMID:26113769

Life-Span Differences in the Uses and Gratifications of Tablets: Implications for Older Adults.

PubMed

Magsamen-Conrad, Kate; Dowd, John; Abuljadail, Mohammad; Alsulaiman, Saud; Shareefi, Adnan

2015-11-01

This study extends Uses and Gratifications theory by examining the uses and gratifications of a new technological device, the tablet computer, and investigating the differential uses and gratifications of tablet computers across the life-span. First, we utilized a six-week tablet training intervention to adapt and extend existing measures to the tablet as a technological device. Next, we used paper-based and online surveys ( N =847), we confirmed four main uses of tablets: 1) Information Seeking, 2) Relationship Maintenance, 3) Style, 4) Amusement and Killing time, and added one additional use category 5) Organization. We discovered differences among the five main uses of tablets across the life-span, with older adults using tablets the least overall. Builders, Boomers, GenX and GenY all reported the highest means for information seeking. Finally, we used a structural equation model to examine how uses and gratifications predicts hours of tablet use. The study provides limitations and suggestions for future research and marketers. In particular, this study offers insight to the relevancy of theory as it applies to particular information and communication technologies and consideration of how different periods in the life-span affect tablet motivations.

Increased iron supplied through Fet3p results in replicative life span extension of Saccharomyces cerevisiae under conditions requiring respiratory metabolism.

PubMed

Botta, Gabriela; Turn, Christina S; Quintyne, Nicholas J; Kirchman, Paul A

2011-10-01

We have previously shown that copper supplementation extends the replicative life span of Saccharomyces cerevisiae when grown under conditions forcing cells to respire. We now show that copper's effect on life span is through Fet3p, a copper containing enzyme responsible for high affinity transport of iron into yeast cells. Life span extensions can also be obtained by supplementing the growth medium with 1mM ferric chloride. Extension by high iron levels is still dependent on the presence of Fet3p. Life span extension by iron or copper requires growth on media containing glycerol as the sole carbon source, which forces yeast to respire. Yeast grown on glucose containing media supplemented with iron show no extension of life span. The iron associated with cells grown in media supplemented with copper or iron is 1.4-1.8 times that of cells grown without copper or iron supplementation. As with copper supplementation, iron supplementation partially rescues the life span of superoxide dismutase mutants. Cells grown with copper supplementation display decreased production of superoxide as measured by dihydroethidium staining. Copyright © 2011 Elsevier Inc. All rights reserved.

Increase of Reproductive Life Span Delays Age of Onset of Parkinson’s Disease

PubMed Central

Frentzel, Dominik; Judanin, Grigorij; Borozdina, Olga; Klucken, Jochen; Winkler, Jürgen; Schlachetzki, Johannes C. M.

2017-01-01

One striking observation in Parkinson’s disease (PD) is the remarkable gender difference in incidence and prevalence of the disease. Data on gender differences with regard to disease onset, motor and non-motor symptoms, and dopaminergic medication are limited. Furthermore, whether estrogen status affects disease onset and progression of PD is controversially discussed. In this retrospective single center study, we extracted clinical data of 226 ambulatory PD patients and compared age of disease onset, disease stage, motor impairment, non-motor symptoms, and dopaminergic medication between genders. We applied a matched-pairs design to adjust for age and disease duration. To determine the effect of estrogen-related reproductive factors including number of children, age at menarche, and menopause on the age of onset, we applied a standardized questionnaire and performed a regression analysis. The male to female ratio in the present PD cohort was 1.9:1 (147 men vs. 79 women). Male patients showed increased motor impairment than female patients. The levodopa equivalent daily dose was increased by 18.9% in male patients compared to female patients. Matched-pairs analysis confirmed the increased dose of dopaminergic medication in male patients. No differences were observed in age of onset, type of medication, and non-motor symptoms between both groups. Female reproductive factors including number of children, age at menarche, and age at menopause were positively associated with a delay of disease onset up to 30 months. The disease-modifying role of estrogen-related outcome measures warrants further clinical and experimental studies targeting gender differences, specifically hormone-dependent pathways in PD. PMID:28871235

Physical Performance Across the Adult Life Span: Correlates With Age and Physical Activity.

PubMed

Hall, Katherine S; Cohen, Harvey J; Pieper, Carl F; Fillenbaum, Gerda G; Kraus, William E; Huffman, Kim M; Cornish, Melissa A; Shiloh, Andrew; Flynn, Christy; Sloane, Richard; Newby, L Kristin; Morey, Miriam C

2017-04-01

A number of large-scale population studies have provided valuable information about physical performance in aged individuals; however, there is little information about trajectories of function and associations with age across the adult life span. We developed a mobility-focused physical performance screener designed to be appropriate for the adult life span. The physical performance battery includes measures of mobility, strength, endurance, and balance. Physical activity (PA) was assessed with accelerometry. We examined age-related trends in physical performance and PA, and the relationship between physical performance and PA across the age range (30-90+), by decade, in 775 participants enrolled in the study 2012-2014. Physical performance was worse with increasing age decade. Although men performed better than women across all ages, the decrement by age group was similar between genders. Worsening physical performance was observed as early as the fifth decade for chair stands and balance and in the sixth decade for gait speed and aerobic endurance. The number and strength of significant associations between physical performance and PA increased with greater age: the greatest number of significant associations was seen in the 60-79 age groups, with fewer reported in the 30-59 and 80-90+ age groups. More PA was associated with better physical function. These results emphasize the importance of a life span approach to studies of function and aging. This work points to the need for a physical performance screener that spans across adulthood as a clinical tool for identifying functional decline. © 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.

Materialism across the life span: An age-period-cohort analysis.

PubMed

Jaspers, Esther D T; Pieters, Rik G M

2016-09-01

This research examined the development of materialism across the life span. Two initial studies revealed that (a) lay beliefs were that materialism declines with age and (b) previous research findings also implied a modest, negative relationship between age and materialism. Yet, previous research has considered age only as a linear control variable, thereby precluding the possibility of more intricate relationships between age and materialism. Moreover, prior studies have relied on cross-sectional data and thus confound age and cohort effects. To improve on this, the main study used longitudinal data from 8 waves spanning 9 years of over 4,200 individuals (16 to 90 years) to examine age effects on materialism while controlling for cohort and period effects. Using a multivariate multilevel latent growth model, it found that materialism followed a curvilinear trajectory across the life span, with the lowest levels at middle age and higher levels before and after that. Thus, in contrast to lay beliefs, materialism increased in older age. Moreover, age effects on materialism differed markedly between 3 core themes of materialism: acquisition centrality, possession-defined success, and acquisition as the pursuit of happiness. In particular, acquisition centrality and possession-defined success were higher at younger and older age. Independent of these age effects, older birth cohorts were oriented more toward possession-defined success, whereas younger birth cohorts were oriented more toward acquisition centrality. The economic downturn since 2008 led to a decrease in acquisition as the pursuit of happiness and in desires for personal growth, but to an increase in desires for achievement. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Immune defense and reproductive pace of life in Peromyscus mice.

PubMed

Martin, Lynn B; Weil, Zachary M; Nelson, Randy J

2007-10-01

Immune activity is variable within and among vertebrates despite the potentially large fitness costs of pathogens to their hosts. From the perspective of life history theory, immunological variability may be the consequence of counterbalancing investments in immune defense against other expensive physiological processes, namely, reproduction. In the present study, we tested the hypothesis that immune defense among captive-bred, disease-free Peromyscus mice would be influenced by their reproductive life history strategies. Specifically, we expected that small species that reproduce prolifically and mature rapidly (i.e., fast pace of life) would favor inexpensive, nonspecific immune defenses to promote reproductive proclivity. Alternatively, we expected that large species that mature slowly and invest modestly in reproduction over multiple events (i.e., slow pace of life) would favor developmentally expensive, specific immune defenses and avoid cheap, nonspecific ones because such defenses are predisposed to self-damage. We found that species exhibited either strong ability to kill (gram-negative) bacteria, a developmentally inexpensive defense, or strong ability to produce antibodies against a novel protein, a developmentally expensive defense, but not both. Cell-mediated inflammation also varied significantly among species, but in a unique fashion relative to bacteria killing or antibody production; wound healing was comparatively similar among species. These results indicate that Peromyscus species use immune strategies that are constrained to a dominant axis, but this axis is not determined solely by reproductive pace of life. Further comparisons, ideally with broader phylogenetic coverage, could identify what ecological and evolutionary forces produce the pattern we detected. Importantly, our study indicates that species may not be differentially immunocompetent; rather, they use unique defense strategies to prevent infection.

Reproductive and early life stages pathology - Histopathology workshop report

USGS Publications Warehouse

Bruno, D.W.; Nowak, B.; Elliott, Diane G.

2006-01-01

Pathology occurring during reproduction and larval development represents an important part of the life cycle of fish, and the diseases that affect eggs and larvae often result in significant losses. However, mortality during this period is frequently ignored or poorly researched as the temptation is to replace the losses rather than investigate the causes. A histopathology workshop organised at the newly refurnished laboratory within the Danish Veterinary School was an opportunity to discuss the pathology of selected diseases associated with Reproductive and Early Life Stages Pathology. Several people also kindly provided reference slides.

Post-dauer life span of Caenorhabditis elegans dauer larvae can be modified by X-irradiation.

PubMed

Onodera, Akira; Yanase, Sumino; Ishii, Takamasa; Yasuda, Kayo; Miyazawa, Masaki; Hartman, Philip S; Ishii, Naoaki

2010-01-01

The time spent as a dauer larva does not affect adult life span in Caenorhabditis elegans, as if aging is suspended in this quiescent developmental stage. We now report that modest doses X-irradiation of dauer larvae increased their post-dauer longevity. Post-irradiation incubation of young dauer larvae did not modify this beneficial effect of radiation. Conversely, holding dauer larvae prior to irradiation rendered them refractory to this X-radiation-induced response. We present a model to explain these results. These experiments demonstrate that dauer larvae provide an excellent opportunity to study mechanisms by which X irradiation can extend life span.

Implication of Ca2+ in the regulation of replicative life span of budding yeast.

PubMed

Tsubakiyama, Ryohei; Mizunuma, Masaki; Gengyo, Anri; Yamamoto, Josuke; Kume, Kazunori; Miyakawa, Tokichi; Hirata, Dai

2011-08-19

In eukaryotic cells, Ca(2+)-triggered signaling pathways are used to regulate a wide variety of cellular processes. Calcineurin, a highly conserved Ca(2+)/calmodulin-dependent protein phosphatase, plays key roles in the regulation of diverse biological processes in organisms ranging from yeast to humans. We isolated a mutant of the SIR3 gene, implicated in the regulation of life span, as a suppressor of the Ca(2+) sensitivity of zds1Δ cells in the budding yeast Saccharomyces cerevisiae. Therefore, we investigated a relationship between Ca(2+) signaling and life span in yeast. Here we show that Ca(2+) affected the replicative life span (RLS) of yeast. Increased external and intracellular Ca(2+) levels caused a reduction in their RLS. Consistently, the increase in calcineurin activity by either the zds1 deletion or the constitutively activated calcineurin reduced RLS. Indeed, the shortened RLS of zds1Δ cells was suppressed by the calcineurin deletion. Further, the calcineurin deletion per se promoted aging without impairing the gene silencing typically observed in short-lived sir mutants, indicating that calcineurin plays an important role in a regulation of RLS even under normal growth condition. Thus, our results indicate that Ca(2+) homeostasis/Ca(2+) signaling are required to regulate longevity in budding yeast.

Corrigendum: Childhood Adversity, Self-Esteem, and Diurnal Cortisol Profiles Across the Life Span.

PubMed

2018-01-01

Original article: Zilioli, S., Slatcher, R. B., Chi, P., Li, X., Zhao, J., & Zhao, G. (2016). Childhood adversity, self-esteem, and diurnal cortisol profiles across the life span. Psychological Science, 27, 1249-1265. doi:10.1177/0956797616658287.

Quantifying the Structure of Free Association Networks across the Life Span

ERIC Educational Resources Information Center

Dubossarsky, Haim; De Deyne, Simon; Hills, Thomas T.

2017-01-01

We investigate how the mental lexicon changes over the life span using free association data from over 8,000 individuals, ranging from 10 to 84 years of age, with more than 400 cue words per age group. Using network analysis, with words as nodes and edges defined by the strength of shared associations, we find that associative networks evolve in a…

eRapa Restores A Normal Life Span in a FAP Mouse Model

PubMed Central

Hasty, Paul; Livi, Carolina B.; Dodds, Sherry G.; Jones, Diane; Strong, Randy; Javors, Martin; Fischer, Kathleen E.; Sloane, Lauren; Murthy, Kruthi; Hubbard, Gene; Sun, Lishi; Hurez, Vincent; Curiel, Tyler J.; Sharp, Zelton Dave

2014-01-01

Mutation of a single copy of the adenomatous polyposis coli (APC) gene results in familial adenomatous polyposis (FAP), which confers an extremely high risk for colon cancer. ApcMin/+ mice exhibit multiple intestinal neoplasia (MIN) that causes anemia and death from bleeding by 6 months. Mechanistic target of rapamycin complex 1 (mTORC1) inhibitors were shown to improve ApcMin/+ mouse survival when administered by oral gavage or added directly to the chow, but these mice still died from neoplasia well short of a natural life span. The National Institute of Aging Intervention Testing Program showed that enterically targeted rapamycin (eRapa) extended life span for wild type genetically heterogeneous mice in part by inhibiting age-associated cancer. We hypothesized that eRapa would be effective in preventing neoplasia and extend survival of ApcMin/+ mice. We show that eRapa improved survival for ApcMin/+ mice in a dose-dependent manner. Remarkably, and in contrast to previous reports, most of the ApcMin/+ mice fed 42 ppm eRapa lived beyond the median life span reported for wild type syngeneic mice. Furthermore, chronic eRapa did not cause detrimental immune effects in mouse models of cancer, infection or autoimmunity; thus, assuaging concerns that chronic rapamycin treatment suppresses immunity. Our studies suggest that a novel formulation (enteric targeting) of a well-known and widely used drug (rapamycin) can dramatically improve its efficacy in targeted settings. eRapa or other mTORC1 inhibitors could serve as effective cancer preventatives for people with FAP without suppressing the immune system, thus reducing the dependency on surgery as standard therapy. PMID:24282255

Age Stereotypes and Self-Views Revisited: Patterns of Internalization and Projection Processes Across the Life Span.

PubMed

Kornadt, Anna E; Voss, Peggy; Rothermund, Klaus

2017-07-01

We investigated processes of age stereotype internalization into the self and projection of self-views onto age stereotypes from a life-span perspective, taking age-related differences in the relevance of life domains into account. Age stereotypes and self-views in eight life domains were assessed in a sample of N = 593 persons aged 30-80 years (T1) at two time points that were separated by a 4-year time interval. We estimated cross-lagged projection and internalization effects in multigroup structural equation models. Internalization and projection effects were contingent on age group and life domain: Internalization effects were strongest in the young and middle-aged groups and emerged in the domains family, personality, work, and leisure. Projection effects in different domains were most pronounced for older participants. Our findings suggest that the internalization of age stereotypes is triggered by domain-specific expectations of impending age-related changes and transitions during certain phases of the life span. Projection processes, however, seem to occur in response to changes that have already been experienced by the individual. Our study demonstrates the dynamic interrelation of age stereotypes and self-views across the life course and highlights the importance of a differentiated, life-span perspective for the understanding of these mechanisms. © 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.

Consilience and Life History Theory: From Genes to Brain to Reproductive Strategy

ERIC Educational Resources Information Center

Figueredo, Aurelio Jose; Vasquez, Geneva; Brumbach, Barbara H.; Schneider, Stephanie M. R.; Sefcek, Jon A.; Tal, Ilanit R.; Hill, Dawn; Wenner, Christopher J.; Jacobs, W. Jake

2006-01-01

We describe an integrated theory of individual differences that traces the behavioral development of life history from genes to brain to reproductive strategy. We provide evidence that a single common factor, the K-Factor, underpins a variety of life-history parameters, including an assortment of sexual, reproductive, parental, familial, and…

Shorter Life Span of Microorganisms and Plants as a Consequence of Shielded Magnetic Environment

NASA Astrophysics Data System (ADS)

Dobrota, C.; Piso, I. M.; Bathory, D.

The geomagnetic field is an essential environmental factor for life and health on this planet. In order to survey how magnetic fields affect the life span and the nitrogenase (an iron-sulphur enzyme) activity of Azotobacter chroococcum as well as the life span, the main organic synthesis and the water balance of plants (22 species), the biological tests were incubated under shielded magnetic field and also in normal geo-magnetic environment. The shielding level was about 10-6 of the terrestrial magnetic field.Life cycles of all organisms require the co-ordinated control of a complex set of interlocked physiological processes and metabolic pathways. Such processes are likely to be regulated by a large number of genes. Our researches suggest that the main point in biological structures, which seems to be affected by the low magnetic environment, is the water molecule. Magnetic field induces a molecular alignment. Under shielded conditions, unstructured water molecules with fewer hydrogen bonds, which are producing a more reactive environment, are occurring. As compared to control, the life span of both microorganisms and plants was shorter in shielded environment. A higher nitrogenase affinity for the substrate was recorded in normal geo-magnetic field compared to low magnetic field. The synthesis of carbohydrates, lipids, proteins and enzymes was modified under experimental conditions. The stomatal conductance was higher between 158 and 300% in shielded environment indicating an important water loss from the plant cells.Our results support the idea that the shielded magnetic environment induces different reactions depending on the time of exposure and on the main metabolic pathways of the cells.

Deleting the 14-3-3 protein Bmh1 extends life span in Saccharomyces cerevisiae by increasing stress response.

PubMed

Wang, Chen; Skinner, Craig; Easlon, Erin; Lin, Su-Ju

2009-12-01

Enhanced stress response has been suggested to promote longevity in many species. Calorie restriction (CR) and conserved nutrient-sensing target of rapamycin (TOR) and protein kinase A (PKA) pathways have also been suggested to extend life span by increasing stress response, which protects cells from age-dependent accumulation of oxidative damages. Here we show that deleting the yeast 14-3-3 protein, Bmh1, extends chronological life span (CLS) by activating the stress response. 14-3-3 proteins are highly conserved chaperone-like proteins that play important roles in many cellular processes. bmh1Delta-induced heat resistance and CLS extension require the general stress-response transcription factors Msn2, Msn4, and Rim15. The bmh1Delta mutant also displays a decreased reactive oxygen species level and increased heat-shock-element-driven transcription activity. We also show that BMH1 genetically interacts with CR and conserved nutrient-sensing TOR- and PKA-signaling pathways to regulate life span. Interestingly, the level of phosphorylated Ser238 on Bmh1 increases during chronological aging, which is delayed by CR or by reduced TOR activities. In addition, we demonstrate that PKA can directly phosphorylate Ser238 on Bmh1. The status of Bmh1 phosphorylation is therefore likely to play important roles in life-span regulation. Together, our studies suggest that phosphorylated Bmh1 may cause inhibitory effects on downstream longevity factors, including stress-response proteins. Deleting Bmh1 may eliminate the inhibitory effects of Bmh1 on these longevity factors and therefore extends life span.

Life-Span Issues in the Fair and Non-Discriminatory Evaluation of Workers.

ERIC Educational Resources Information Center

Alexander, Ralph A.; Barrett, Gerald V.

Until recently, older workers have not been recognized as a group requiring special attention in the area of fair employment practices. Thus, progress has been slow towards the development of valid and reliable indices of performance which are applicable across the life span. Research shows that many measures of employee evaluation provide no…

Fast–slow continuum and reproductive strategies structure plant life-history variation worldwide

PubMed Central

Salguero-Gómez, Roberto; Jones, Owen R.; Jongejans, Eelke; Blomberg, Simon P.; Hodgson, David J.; Mbeau-Ache, Cyril; Zuidema, Pieter A.; de Kroon, Hans; Buckley, Yvonne M.

2016-01-01

The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous variation in life history are poorly understood. We use demographic data from 418 plant species in the wild, from annual herbs to supercentennial trees, to examine how growth form, habitat, and phylogenetic relationships structure plant life histories and to develop a framework to predict population performance. We show that 55% of the variation in plant life-history strategies is adequately characterized using two independent axes: the fast–slow continuum, including fast-growing, short-lived plant species at one end and slow-growing, long-lived species at the other, and a reproductive strategy axis, with highly reproductive, iteroparous species at one extreme and poorly reproductive, semelparous plants with frequent shrinkage at the other. Our findings remain consistent across major habitats and are minimally affected by plant growth form and phylogenetic ancestry, suggesting that the relative independence of the fast–slow and reproduction strategy axes is general in the plant kingdom. Our findings have similarities with how life-history strategies are structured in mammals, birds, and reptiles. The position of plant species populations in the 2D space produced by both axes predicts their rate of recovery from disturbances and population growth rate. This life-history framework may complement trait-based frameworks on leaf and wood economics; together these frameworks may allow prediction of responses of plants to anthropogenic disturbances and changing environments. PMID:26699477

Fast-slow continuum and reproductive strategies structure plant life-history variation worldwide.

PubMed

Salguero-Gómez, Roberto; Jones, Owen R; Jongejans, Eelke; Blomberg, Simon P; Hodgson, David J; Mbeau-Ache, Cyril; Zuidema, Pieter A; de Kroon, Hans; Buckley, Yvonne M

2016-01-05

The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous variation in life history are poorly understood. We use demographic data from 418 plant species in the wild, from annual herbs to supercentennial trees, to examine how growth form, habitat, and phylogenetic relationships structure plant life histories and to develop a framework to predict population performance. We show that 55% of the variation in plant life-history strategies is adequately characterized using two independent axes: the fast-slow continuum, including fast-growing, short-lived plant species at one end and slow-growing, long-lived species at the other, and a reproductive strategy axis, with highly reproductive, iteroparous species at one extreme and poorly reproductive, semelparous plants with frequent shrinkage at the other. Our findings remain consistent across major habitats and are minimally affected by plant growth form and phylogenetic ancestry, suggesting that the relative independence of the fast-slow and reproduction strategy axes is general in the plant kingdom. Our findings have similarities with how life-history strategies are structured in mammals, birds, and reptiles. The position of plant species populations in the 2D space produced by both axes predicts their rate of recovery from disturbances and population growth rate. This life-history framework may complement trait-based frameworks on leaf and wood economics; together these frameworks may allow prediction of responses of plants to anthropogenic disturbances and changing environments.

Atomic Bomb Survivors Life-Span Study

PubMed Central

Dobrzyński, Ludwik

2015-01-01

The atomic bomb survivors life-span study (LSS) is often claimed to support the linear no-threshold hypothesis (LNTH) of radiation carcinogenesis. This paper shows that this claim is baseless. The LSS data are equally or better described by an s-shaped dependence on radiation exposure with a threshold of about 0.3 Sievert (Sv) and saturation level at about 1.5 Sv. A Monte-Carlo simulation of possible LSS outcomes demonstrates that, given the weak statistical power, LSS cannot provide support for LNTH. Even if the LNTH is used at low dose and dose rates, its estimation of excess cancer mortality should be communicated as 2.5% per Sv, i.e., an increase of cancer mortality from about 20% spontaneous mortality to about 22.5% per Sv, which is about half of the usually cited value. The impact of the “neutron discrepancy problem” – the apparent difference between the calculated and measured values of neutron flux in Hiroshima – was studied and found to be marginal. Major revision of the radiation risk assessment paradigm is required. PMID:26673526

Life-span extension by dietary restriction is mediated by NLP-7 signaling and coelomocyte endocytosis in C. elegans.

PubMed

Park, Sang-Kyu; Link, Christopher D; Johnson, Thomas E

2010-02-01

Recent studies have shown that the rate of aging can be modulated by diverse interventions. Dietary restriction is the most widely used intervention to promote longevity; however, the mechanisms underlying the effect of dietary restriction remain elusive. In a previous study, we identified two novel genes, nlp-7 and cup-4, required for normal longevity in Caenorhabditis elegans. nlp-7 is one of a set of neuropeptide-like protein genes; cup-4 encodes an ion-channel involved in endocytosis by coelomocytes. Here, we assess whether nlp-7 and cup-4 mediate longevity increases by dietary restriction. RNAi of nlp-7 or cup-4 significantly reduces the life span of the eat-2 mutant, a genetic model of dietary restriction, but has no effect on the life span of long-lived mutants resulting from reduced insulin/IGF-1 signaling or dysfunction of the mitochondrial electron transport chain. The life-span extension observed in wild-type N2 worms by dietary restriction using bacterial dilution is prevented significantly in nlp-7 and cup-4 mutants. RNAi knockdown of genes encoding candidate receptors of NLP-7 and genes involved in endocytosis by coelomocytes also specifically shorten the life span of the eat-2 mutant. We conclude that two novel pathways, NLP-7 signaling and endocytosis by coelomocytes, are required for life extension under dietary restriction in C. elegans.

Reconstructing life history of hominids and humans.

PubMed

Crews, Douglas E; Gerber, Linda M

2003-06-01

Aspects of life history, such as processes and timing of development, age at maturation, and life span are consistently associated with one another across the animal kingdom. Species that develop rapidly tend to mature and reproduce early, have many offspring, and exhibit shorter life spans (r-selection) than those that develop slowly, have extended periods of premature growth, mature later in life, reproduce later and less frequently, have few offspring and/or single births, and exhibit extended life spans (K-selection). In general, primates are among the most K-selected of species. A suite of highly derived life history traits characterizes humans. Among these are physically immature neonates, slowed somatic development both in utero and post-natally, late attainment of reproductive maturity and first birth, and extended post-mature survival. Exactly when, why, and through what types of evolutionary interactions this suite arose is currently the subject of much conjecture and debate. Humankind's biocultural adaptations have helped to structure human life history evolution in unique ways not seen in other animal species. Among all species, life history traits may respond rapidly to alterations in selective pressures through hormonal processes. Selective pressures on life history likely varied widely among hominids and humans over their evolutionary history. This suggests that current patterns of human growth, development, maturation, reproduction, and post-mature survival may be of recent genesis, rather then long-standing adaptations. Thus, life history patterns observed among contemporary human and chimpanzee populations may provide little insight to those that existed earlier in hominid/human evolution.

Life-history trade-offs mediate 'personality' variation in two colour morphs of the pea aphid, Acyrthosiphon pisum.

PubMed

Schuett, Wiebke; Dall, Sasha R X; Kloesener, Michaela H; Baeumer, Jana; Beinlich, Felix; Eggers, Till

2015-01-01

Life-history trade-offs are considered a major driving force in the emergence of consistent behavioural differences (personality variation); but empirical tests are scarce. We investigated links between a personality trait (escape response), life-history and state variables (growth rate, size and age at first reproduction, age-dependent reproductive rates, lifetime reproductive success, life span) in red and green colour morphs of clonal pea aphids, Acyrthosiphon pisum. Escape response (dropping/non-dropping off a plant upon a predatory attack) was measured repeatedly to classify individuals as consistent droppers, consistent nondroppers or inconsistents. Red morphs experienced stronger trade-offs between early reproduction and life span than green morphs; and red consistent (non)droppers had highest lifetime reproductive success. Red droppers followed a risk-averse life-history strategy (high late reproduction), red nondroppers a risk-prone strategy (high early reproduction), while reproductive rates were equivalent for all green behavioural types and red inconsistents. This suggests that red morphs suffer the highest costs of dropping (they are most conspicuous to predators), which 'equivalates' fitness payoffs to both risk-takers (red non-droppers) and risk-averse red droppers. The strong trade-off also means that committing to a particular lifestyle (being consistent) maximises fitness. Our study suggests that life-history trade-offs likely mediate personality variation but effects might depend on interactions with other organismal characteristics (here: colour morph). © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Life-span development of visual working memory: when is feature binding difficult?

PubMed

Cowan, Nelson; Naveh-Benjamin, Moshe; Kilb, Angela; Saults, J Scott

2006-11-01

We asked whether the ability to keep in working memory the binding between a visual object and its spatial location changes with development across the life span more than memory for item information. Paired arrays of colored squares were identical or differed in the color of one square, and in the latter case, the changed color was unique on that trial (item change) or was duplicated elsewhere in the array (color-location binding change). Children (8-10 and 11-12 years old) and older adults (65-85 years old) showed deficits relative to young adults. These were only partly simulated by dividing attention in young adults. The older adults had an additional deficiency, specifically in binding information, which was evident only when item- and binding-change trials were mixed together. In that situation, the older adults often overlooked the more subtle, binding-type changes. Some working memory processes related to binding undergo life-span development in an inverted-U shape, whereas other, bias- and salience-related processes that influence the use of binding information seem to develop monotonically.

Health costs of reproduction are minimal despite high fertility, mortality and subsistence lifestyle

PubMed Central

Gurven, Michael; Costa, Megan; Ben Trumble; Stieglitz, Jonathan; Beheim, Bret; Eid Rodriguez, Daniel; Hooper, Paul L.; Kaplan, Hillard

2016-01-01

Women exhibit greater morbidity than men despite higher life expectancy. An evolutionary life history framework predicts that energy invested in reproduction trades-off against investments in maintenance and survival. Direct costs of reproduction may therefore contribute to higher morbidity, especially for women given their greater direct energetic contributions to reproduction. We explore multiple indicators of somatic condition among Tsimane forager-horticulturalist women (Total Fertility Rate = 9.1; n =  592 aged 15–44 years, n = 277 aged 45+). We test whether cumulative live births and the pace of reproduction are associated with nutritional status and immune function using longitudinal data spanning 10 years. Higher parity and faster reproductive pace are associated with lower nutritional status (indicated by weight, body mass index, body fat) in a cross-section, but longitudinal analyses show improvements in women’s nutritional status with age. Biomarkers of immune function and anemia vary little with parity or pace of reproduction. Our findings demonstrate that even under energy-limited and infectious conditions, women are buffered from the potential depleting effects of rapid reproduction and compound offspring dependency characteristic of human life histories. PMID:27436412

Health costs of reproduction are minimal despite high fertility, mortality and subsistence lifestyle.

PubMed

Gurven, Michael; Costa, Megan; Ben Trumble; Stieglitz, Jonathan; Beheim, Bret; Eid Rodriguez, Daniel; Hooper, Paul L; Kaplan, Hillard

2016-07-20

Women exhibit greater morbidity than men despite higher life expectancy. An evolutionary life history framework predicts that energy invested in reproduction trades-off against investments in maintenance and survival. Direct costs of reproduction may therefore contribute to higher morbidity, especially for women given their greater direct energetic contributions to reproduction. We explore multiple indicators of somatic condition among Tsimane forager-horticulturalist women (Total Fertility Rate = 9.1; n =  592 aged 15-44 years, n = 277 aged 45+). We test whether cumulative live births and the pace of reproduction are associated with nutritional status and immune function using longitudinal data spanning 10 years. Higher parity and faster reproductive pace are associated with lower nutritional status (indicated by weight, body mass index, body fat) in a cross-section, but longitudinal analyses show improvements in women's nutritional status with age. Biomarkers of immune function and anemia vary little with parity or pace of reproduction. Our findings demonstrate that even under energy-limited and infectious conditions, women are buffered from the potential depleting effects of rapid reproduction and compound offspring dependency characteristic of human life histories.

Reduced Ssy1-Ptr3-Ssy5 (SPS) signaling extends replicative life span by enhancing NAD+ homeostasis in Saccharomyces cerevisiae.

PubMed

Tsang, Felicia; James, Christol; Kato, Michiko; Myers, Victoria; Ilyas, Irtqa; Tsang, Matthew; Lin, Su-Ju

2015-05-15

Attenuated nutrient signaling extends the life span in yeast and higher eukaryotes; however, the mechanisms are not completely understood. Here we identify the Ssy1-Ptr3-Ssy5 (SPS) amino acid sensing pathway as a novel longevity factor. A null mutation of SSY5 (ssy5Δ) increases replicative life span (RLS) by ∼50%. Our results demonstrate that several NAD(+) homeostasis factors play key roles in this life span extension. First, expression of the putative malate-pyruvate NADH shuttle increases in ssy5Δ cells, and deleting components of this shuttle, MAE1 and OAC1, largely abolishes RLS extension. Next, we show that Stp1, a transcription factor of the SPS pathway, directly binds to the promoter of MAE1 and OAC1 to regulate their expression. Additionally, deletion of SSY5 increases nicotinamide riboside (NR) levels and phosphate-responsive (PHO) signaling activity, suggesting that ssy5Δ increases NR salvaging. This increase contributes to NAD(+) homeostasis, partially ameliorating the NAD(+) deficiency and rescuing the short life span of the npt1Δ mutant. Moreover, we observed that vacuolar phosphatase, Pho8, is partially required for ssy5Δ-mediated NR increase and RLS extension. Together, our studies present evidence that supports SPS signaling is a novel NAD(+) homeostasis factor and ssy5Δ-mediated life span extension is likely due to concomitantly increased mitochondrial and vacuolar function. Our findings may contribute to understanding the molecular basis of NAD(+) metabolism, cellular life span, and diseases associated with NAD(+) deficiency and aging. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Life-Span Development of Visual Working Memory: When Is Feature Binding Difficult?

ERIC Educational Resources Information Center

Cowan, Nelson; Naveh-Benjamin, Moshe; Kilb, Angela; Saults, J. Scott

2006-01-01

We asked whether the ability to keep in working memory the binding between a visual object and its spatial location changes with development across the life span more than memory for item information. Paired arrays of colored squares were identical or differed in the color of one square, and in the latter case, the changed color was unique on…

Improvement/Maintenance and Reorientation as Central Features of Coping with Major Life Change and Loss: Contributions of Three Life-Span Theories

ERIC Educational Resources Information Center

Boerner, Kathrin; Jopp, Daniela

2007-01-01

This article focuses on the common and unique contributions of three major life-span theories in addressing improvement/maintenance and reorientation, which represent central processes of coping with major life change and loss. For this purpose, we review and compare the dual-process model of assimilative and accommodative coping, the model of…

Life-Span Exposure to Low Doses of Aspartame Beginning during Prenatal Life Increases Cancer Effects in Rats

PubMed Central

Soffritti, Morando; Belpoggi, Fiorella; Tibaldi, Eva; Esposti, Davide Degli; Lauriola, Michelina

2007-01-01

Background In a previous study conducted at the Cesare Maltoni Cancer Research Center of the European Ramazzini Foundation (CMCRC/ERF), we demonstrated for the first time that aspartame (APM) is a multipotent carcinogenic agent when various doses are administered with feed to Sprague-Dawley rats from 8 weeks of age throughout the life span. Objective The aim of this second study is to better quantify the carcinogenic risk of APM, beginning treatment during fetal life. Methods We studied groups of 70–95 male and female Sprague-Dawley rats administered APM (2,000, 400, or 0 ppm) with feed from the 12th day of fetal life until natural death. Results Our results show a) a significant dose-related increase of malignant tumor–bearing animals in males (p < 0.01), particularly in the group treated with 2,000 ppm APM (p < 0.01); b) a significant increase in incidence of lymphomas/leukemias in males treated with 2,000 ppm (p < 0.05) and a significant dose-related increase in incidence of lymphomas/leukemias in females (p < 0.01), particularly in the 2,000-ppm group (p < 0.01); and c) a significant dose-related increase in incidence of mammary cancer in females (p < 0.05), particularly in the 2,000-ppm group (p < 0.05). Conclusions The results of this carcinogenicity bioassay confirm and reinforce the first experimental demonstration of APM’s multipotential carcinogenicity at a dose level close to the acceptable daily intake for humans. Furthermore, the study demonstrates that when life-span exposure to APM begins during fetal life, its carcinogenic effects are increased. PMID:17805418

Early-life stress and reproductive cost: A two-hit developmental model of accelerated aging?

PubMed

Shalev, Idan; Belsky, Jay

2016-05-01

Two seemingly independent bodies of research suggest a two-hit model of accelerated aging, one highlighting early-life stress and the other reproduction. The first, informed by developmental models of early-life stress, highlights reduced longevity effects of early adversity on telomere erosion, whereas the second, informed by evolutionary theories of aging, highlights such effects with regard to reproductive cost (in females). The fact that both early-life adversity and reproductive effort are associated with shorter telomeres and increased oxidative stress raises the prospect, consistent with life-history theory, that these two theoretical frameworks currently informing much research are tapping into the same evolutionary-developmental process of increased senescence and reduced longevity. Here we propose a mechanistic view of a two-hit model of accelerated aging in human females through (a) early-life adversity and (b) early reproduction, via a process of telomere erosion, while highlighting mediating biological embedding mechanisms that might link these two developmental aging processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

The role of early life nutrition in programming of reproductive function.

PubMed

Chadio, S; Kotsampasi, B

2014-02-01

Accumulating evidence suggest that the concept of programming can also be applied to reproductive development and function, representing an ever expanding research area. Recently issues such as peri- or even preconceptional nutrition, transgenerational effects and underlying mechanisms have received considerable attention. The present chapter presents the existed evidence and reviews the available data from numerous animal and human studies on the effects of early life nutritional environment on adult reproductive function. Specific outcomes depend on the severity, duration and stage of development when nutritional perturbations are imposed, while sex-specific effects are also manifested. Apart from undernutrition, effects of relative overnutrition as well as the complex interactions between pre- and postnatal nutrition is of high importance, especially in the context of our days obesity epidemic. Mechanisms underlying reproductive programming are yet unclear, but may include a role for epigenetic modifications. Epigenetic modulation of critical genes involved in the control of reproductive function and potential intergenerational effects represent an exciting area of interdisciplinary research toward the development of new nutritional approaches during pre- and postnatal periods to ensure reproductive health in later life.

Loss of the clock protein PER2 shortens the erythrocyte life span in mice.

PubMed

Sun, Qi; Zhao, Yue; Yang, Yunxia; Yang, Xiao; Li, Minghui; Xu, Xi; Wen, Dan; Wang, Junsong; Zhang, Jianfa

2017-07-28

Cell proliferation and release from the bone marrow have been demonstrated to be controlled by circadian rhythms in both humans and mice. However, it is unclear whether local circadian clocks in the bone marrow influence physiological functions and life span of erythrocytes. Here, we report that loss of the clock gene Per2 significantly decreased erythrocyte life span. Mice deficient in Per2 were more susceptible to acute stresses in the erythrocytes, becoming severely anemic upon phenylhydrazine, osmotic, and H 2 O 2 challenges. 1 H NMR-based metabolomics analysis revealed that the Per2 depletion causes significant changes in metabolic profiles of erythrocytes, including increased lactate and decreased ATP levels compared with wild-type mice. The lower ATP levels were associated with hyperfunction of Na + /K + -ATPase activity in Per2 -null erythrocytes, and inhibition of Na + /K + -ATPase activity by ouabain efficiently rescued ATP levels. Per2 -null mice displayed increased levels of Na + /K + -ATPase α1 (ATP1A1) in the erythrocyte membrane, and transfection of Per2 cDNA into the erythroleukemic cell line TF-1 inhibited Atp1a1 expression. Furthermore, we observed that PER2 regulates Atp1a1 transcription through interacting with trans-acting transcription factor 1 (SP1). Our findings reveal that Per2 function in the bone marrow is required for the regulation of life span in circulating erythrocytes. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Effects of a Short Strategy Training on Metacognitive Monitoring across the Life-Span

ERIC Educational Resources Information Center

von der Linden, Nicole; Löffler, Elisabeth; Schneider, Wolfgang

2015-01-01

The present study was conducted to explore the potential positive influence of a short strategy training on metacognitive monitoring competencies covering a life-span approach. Participants of four age groups (3rd-grade children, adolescents, younger and older adults) concluded a paired-associate learning task. Additionally, they gave delayed…

The role of fecundity and reproductive effort in defining life-history strategies of North American freshwater mussels.

PubMed

Haag, Wendell R

2013-08-01

Selection is expected to optimize reproductive investment resulting in characteristic trade-offs among traits such as brood size, offspring size, somatic maintenance, and lifespan; relative patterns of energy allocation to these functions are important in defining life-history strategies. Freshwater mussels are a diverse and imperiled component of aquatic ecosystems, but little is known about their life-history strategies, particularly patterns of fecundity and reproductive effort. Because mussels have an unusual life cycle in which larvae (glochidia) are obligate parasites on fishes, differences in host relationships are expected to influence patterns of reproductive output among species. I investigated fecundity and reproductive effort (RE) and their relationships to other life-history traits for a taxonomically broad cross section of North American mussel diversity. Annual fecundity of North American mussel species spans nearly four orders of magnitude, ranging from < 2000 to 10 million, but most species have considerably lower fecundity than previous generalizations, which portrayed the group as having uniformly high fecundity (e.g. > 200000). Estimates of RE also were highly variable, ranging among species from 0.06 to 25.4%. Median fecundity and RE differed among phylogenetic groups, but patterns for these two traits differed in several ways. For example, the tribe Anodontini had relatively low median fecundity but had the highest RE of any group. Within and among species, body size was a strong predictor of fecundity and explained a high percentage of variation in fecundity among species. Fecundity showed little relationship to other life-history traits including glochidial size, lifespan, brooding strategies, or host strategies. The only apparent trade-off evident among these traits was the extraordinarily high fecundity of Leptodea, Margaritifera, and Truncilla, which may come at a cost of greatly reduced glochidial size; there was no relationship between

Genome-wide screen in Saccharomyces cerevisiae identifies vacuolar protein sorting, autophagy, biosynthetic, and tRNA methylation genes involved in life span regulation.

PubMed

Fabrizio, Paola; Hoon, Shawn; Shamalnasab, Mehrnaz; Galbani, Abdulaye; Wei, Min; Giaever, Guri; Nislow, Corey; Longo, Valter D

2010-07-15

The study of the chronological life span of Saccharomyces cerevisiae, which measures the survival of populations of non-dividing yeast, has resulted in the identification of homologous genes and pathways that promote aging in organisms ranging from yeast to mammals. Using a competitive genome-wide approach, we performed a screen of a complete set of approximately 4,800 viable deletion mutants to identify genes that either increase or decrease chronological life span. Half of the putative short-/long-lived mutants retested from the primary screen were confirmed, demonstrating the utility of our approach. Deletion of genes involved in vacuolar protein sorting, autophagy, and mitochondrial function shortened life span, confirming that respiration and degradation processes are essential for long-term survival. Among the genes whose deletion significantly extended life span are ACB1, CKA2, and TRM9, implicated in fatty acid transport and biosynthesis, cell signaling, and tRNA methylation, respectively. Deletion of these genes conferred heat-shock resistance, supporting the link between life span extension and cellular protection observed in several model organisms. The high degree of conservation of these novel yeast longevity determinants in other species raises the possibility that their role in senescence might be conserved.

Psychopathology in Williams Syndrome: The Effect of Individual Differences across the Life Span

ERIC Educational Resources Information Center

Dodd, Helen F.; Porter, Melanie A.

2009-01-01

This research aimed to comprehensively explore psychopathology in Williams syndrome (WS) across the life span and evaluate the relationship between psychopathology and age category (child or adult), gender, and cognitive ability. The parents of 50 participants with WS, ages 6-50 years, were interviewed using the Schedule for Affective Disorders…

Spontaneous locomotor activity and life span. A test of the rate of living theory in Drosophila melanogaster.

PubMed

Lints, F A; Le Bourg, E; Lints, C V

1984-01-01

The spontaneous locomotor activity and life span of approximately 600 individuals of both sexes and of three widely different genotypes of Drosophila melanogaster have been measured. Neither at the individual nor at the populational level could a significant correlation between spontaneous locomotor activity and life span be found. The results are discussed in relation with Pearl's [The rate of living, London University Press, London 1928] rate of living theory. That theory has been tested in relation with environmental temperature, oxygen consumption and activity. It is shown that the theory has received no definite confirmation until now.

Twelve fundamental life histories evolving through allocation-dependent fecundity and survival.

PubMed

Johansson, Jacob; Brännström, Åke; Metz, Johan A J; Dieckmann, Ulf

2018-03-01

An organism's life history is closely interlinked with its allocation of energy between growth and reproduction at different life stages. Theoretical models have established that diminishing returns from reproductive investment promote strategies with simultaneous investment into growth and reproduction (indeterminate growth) over strategies with distinct phases of growth and reproduction (determinate growth). We extend this traditional, binary classification by showing that allocation-dependent fecundity and mortality rates allow for a large diversity of optimal allocation schedules. By analyzing a model of organisms that allocate energy between growth and reproduction, we find twelve types of optimal allocation schedules, differing qualitatively in how reproductive allocation increases with body mass. These twelve optimal allocation schedules include types with different combinations of continuous and discontinuous increase in reproduction allocation, in which phases of continuous increase can be decelerating or accelerating. We furthermore investigate how this variation influences growth curves and the expected maximum life span and body size. Our study thus reveals new links between eco-physiological constraints and life-history evolution and underscores how allocation-dependent fitness components may underlie biological diversity.

Two-carbon metabolites, polyphenols and vitamins influence yeast chronological life span in winemaking conditions

PubMed Central

2012-01-01

Background Viability in a non dividing state is referred to as chronological life span (CLS). Most grape juice fermentation happens when Saccharomyces cerevisiae yeast cells have stopped dividing; therefore, CLS is an important factor toward winemaking success. Results We have studied both the physical and chemical determinants influencing yeast CLS. Low pH and heat shorten the maximum wine yeast life span, while hyperosmotic shock extends it. Ethanol plays an important negative role in aging under winemaking conditions, but additional metabolites produced by fermentative metabolism, such as acetaldehyde and acetate, have also a strong impact on longevity. Grape polyphenols quercetin and resveratrol have negative impacts on CLS under winemaking conditions, an unexpected behavior for these potential anti-oxidants. We observed that quercetin inhibits alcohol and aldehyde dehydrogenase activities, and that resveratrol performs a pro-oxidant role during grape juice fermentation. Vitamins nicotinic acid and nicotinamide are precursors of NAD+, and their addition reduces mean longevity during fermentation, suggesting a metabolic unbalance negative for CLS. Moreover, vitamin mix supplementation at the end of fermentation shortens CLS and enhances cell lysis, while amino acids increase life span. Conclusions Wine S. cerevisiae strains are able to sense changes in the environmental conditions and adapt their longevity to them. Yeast death is influenced by the conditions present at the end of wine fermentation, particularly by the concentration of two-carbon metabolites produced by the fermentative metabolism, such as ethanol, acetic acid and acetaldehyde, and also by the grape juice composition, particularly its vitamin content. PMID:22873488

Intermittent Administration of Rapamycin Extends the Life Span of Female C57BL/6J Mice.

PubMed

Arriola Apelo, Sebastian I; Pumper, Cassidy P; Baar, Emma L; Cummings, Nicole E; Lamming, Dudley W

2016-07-01

Inhibition of the mTOR (mechanistic target of rapamycin) signaling pathway by the FDA-approved drug rapamycin promotes life span in numerous model organisms and delays age-related disease in mice. However, the utilization of rapamycin as a therapy for age-related diseases will likely prove challenging due to the serious metabolic and immunological side effects of rapamycin in humans. We recently identified an intermittent rapamycin treatment regimen-2mg/kg administered every 5 days-with a reduced impact on glucose homeostasis and the immune system as compared with chronic treatment; however, the ability of this regimen to extend life span has not been determined. Here, we report for the first time that an intermittent rapamycin treatment regimen starting as late as 20 months of age can extend the life span of female C57BL/6J mice. Our work demonstrates that the anti-aging potential of rapamycin is separable from many of its negative side effects and suggests that carefully designed dosing regimens may permit the safer use of rapamycin and its analogs for the treatment of age-related diseases in humans. © 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 Development of Memory Efficiency and Value-Directed Remembering across the Life Span: A Cross-Sectional Study of Memory and Selectivity

ERIC Educational Resources Information Center

Castel, Alan D.; Humphreys, Kathryn L.; Lee, Steve S.; Galvan, Adriana; Balota, David A.; McCabe, David P.

2011-01-01

Although attentional control and memory change considerably across the life span, no research has examined how the ability to strategically remember important information (i.e., value-directed remembering) changes from childhood to old age. The present study examined this in different age groups across the life span (N = 320, 5-96 years old). A…

Blood volume and red cell life span (M113), part C

NASA Technical Reports Server (NTRS)

Johnson, P. C., Jr.

1973-01-01

Prechamber, in-chamber, and postchamber blood samples taken from Skylab simulation crewmembers did not indicate significant shortening of the red cell life span during the mission. This does not suggest that the space simulation environment could not be associated with red cell enzyme changes. It does show that any changes in enzymes were not sufficiently great to significantly shorten red cell survival. There was no evidence of bone marrow erythropoetic suppression nor was there any evidence of increased red cell destruction.

Evaluation of resveratrol, green tea extract, curcumin, oxaloacetic acid, and medium-chain triglyceride oil on life span of genetically heterogeneous mice.

PubMed

Strong, Randy; Miller, Richard A; Astle, Clinton M; Baur, Joseph A; de Cabo, Rafael; Fernandez, Elizabeth; Guo, Wen; Javors, Martin; Kirkland, James L; Nelson, James F; Sinclair, David A; Teter, Bruce; Williams, David; Zaveri, Nurulain; Nadon, Nancy L; Harrison, David E

2013-01-01

The National Institute on Aging Interventions Testing Program (ITP) was established to evaluate agents that are hypothesized to increase life span and/or health span in genetically heterogeneous mice. Each compound is tested in parallel at three test sites. It is the goal of the ITP to publish all results, negative or positive. We report here on the results of lifelong treatment of mice, beginning at 4 months of age, with each of five agents, that is, green tea extract (GTE), curcumin, oxaloacetic acid, medium-chain triglyceride oil, and resveratrol, on the life span of genetically heterogeneous mice. Each agent was administered beginning at 4 months of age. None of these five agents had a statistically significant effect on life span of male or female mice, by log-rank test, at the concentrations tested, although a secondary analysis suggested that GTE might diminish the risk of midlife deaths in females only.

The Use of Digital Technologies across the Adult Life Span in Distance Education

ERIC Educational Resources Information Center

Jelfs, Anne; Richardson, John T. E.

2013-01-01

In June 2010, a survey was carried out to explore access to digital technology, attitudes to digital technology and approaches to studying across the adult life span in students taking courses with the UK Open University. In total, 7000 people were surveyed, of whom more than 4000 responded. Nearly all these students had access to a computer and…

The Development of Attentional Networks: Cross-Sectional Findings from a Life Span Sample

ERIC Educational Resources Information Center

Waszak, Florian; Li, Shu-Chen; Hommel, Bernhard

2010-01-01

Using a population-based sample of 263 individuals ranging from 6 to 89 years of age, we investigated the gains and losses in the abilities to (a) use exogenous cues to shift attention covertly and (b) ignore conflicting information across the life span. The participants' ability to shift visual attention was tested by a typical Posner-type…

Effect of Ala-Glu-Asp-Gly peptide on life span and development of spontaneous tumors in female rats exposed to different illumination regimes.

PubMed

Vinogradova, I A; Bukalev, A V; Zabezhinski, M A; Semenchenko, A V; Khavinson, V Kh; Anisimov, V N

2007-12-01

The effects of Ala-Glu-Asp-Gly peptide (Epithalon) on the life span and development of spontaneous tumors were studied in female rats exposed to standard, natural for North-Western Russia, and constant illumination. The mean life span of animals exposed to constant or natural illumination decreased by 13.5 and 25.5%, the maximum by 9 and 7 months, respectively, and spontaneous tumors developed much more rapidly than in animals living under conditions of the standard light regimen. Epithalon (0.1 microg daily 5 times a week from the age of 4 months) did not change the life span of rats living under conditions of standard day/night regimen, while in rats exposed to the natural and constant light it promoted prolongation of the maximum life span by 95 and 24 days, respectively. Epithalon prolonged the mean life span of the last 10% of rats exposed to natural and constant illumination, treated with Epithalon, by 137 and 43 days, respectively. This peptide exhibited virtually no effect on the development of spontaneous tumors in rats exposed to standard and constant illumination, but significantly inhibited their development in rats exposed to natural light.

Body Image across the Life Span in Adult Women: The Role of Self-Objectification.

ERIC Educational Resources Information Center

Tiggemann, Marika; Lynch, Jessica E.

2001-01-01

Investigated body image across life span in cross-section of women ages 20-84 years. Found that although body dissatisfaction remained stable, self-objectification, habitual body monitoring, appearance anxiety, and disordered eating all significantly decreased with age. Self- objectification mediated the relationship between age and disordered…

Spermatozoid life-span of two brown seaweeds, Saccharina japonica and Undaria pinnatifida, as measured by fertilization efficiency

NASA Astrophysics Data System (ADS)

Li, Jing; Pang, Shaojun; Liu, Feng; Shan, Tifeng; Gao, Suqin

2013-07-01

During sexual reproduction of seaweeds, spermatozoid (sperm) discharge is triggered by chemical messengers (pheromones) released by the female gametes. The chemotactic ability of the sperm ensures fertilization success. Using unialgal male and female gametophyte material under designated standard gametogenesis testing (SGT) conditions, the potential life-span of the sperm of two seaweeds, Saccharina japonica and Undaria pinnatifida, was assessed by their ability to fertilize eggs. Results show that within 20-30 min after being discharged, sperm of both species could complete fertilization without an apparent decline in fertilization rate. Although fertilization rate 60-120 min after sperm discharge dropped significantly in both species, some sperm were viable enough to fertilize the eggs. In S. japonica, at 12°C, some sperm were able to fertilize eggs up to 12 h after discharge. In both species, egg discharge rates (EDR) in the male and female mixed positive controls were significantly higher than those of all the sperm-testing groups. Doubling the seeded male gametophytes of S. japonica in the SGT tests significantly increased the EDR, further confirming the effect of the presence of the male on the female in terms of facilitating egg discharge from oogonia.

Ageing in a eusocial insect: molecular and physiological characteristics of life span plasticity in the honey bee

PubMed Central

Münch, D.; Amdam, G. V.; Wolschin, F.

2008-01-01

Summary Commonly held views assume that ageing, or senescence, represents an inevitable, passive, and random decline in function that is strongly linked to chronological age. In recent years, genetic intervention of life span regulating pathways, for example, in Drosophila as well as case studies in non-classical animal models, have provided compelling evidence to challenge these views. Rather than comprehensively revisiting studies on the established genetic model systems of ageing, we here focus on an alternative model organism with a wild type (unselected genotype) characterized by a unique diversity in longevity – the honey bee. Honey bee (Apis mellifera) life span varies from a few weeks to more than 2 years. This plasticity is largely controlled by environmental factors. Thereby, although individuals are closely related genetically, distinct life histories can emerge as a function of social environmental change. Another remarkable feature of the honey bee is the occurrence of reverted behavioural ontogeny in the worker (female helper) caste. This behavioural peculiarity is associated with alterations in somatic maintenance functions that are indicative of reverted senescence. Thus, although intraspecific variation in organismal life span is not uncommon, the honey bee holds great promise for gaining insights into regulatory pathways that can shape the time-course of ageing by delaying, halting or even reversing processes of senescence. These aspects provide the setting of our review. We will highlight comparative findings from Drosophila melanogaster and Caenorhabditis elegans in particular, and focus on knowledge spanning from molecular- to behavioural-senescence to elucidate how the honey bee can contribute to novel insights into regulatory mechanisms that underlie plasticity and robustness or irreversibility in ageing. PMID:18728759

Ageing in a eusocial insect: molecular and physiological characteristics of life span plasticity in the honey bee.

PubMed

Münch, D; Amdam, G V; Wolschin, F

2008-01-01

Commonly held views assume that ageing, or senescence, represents an inevitable, passive, and random decline in function that is strongly linked to chronological age. In recent years, genetic intervention of life span regulating pathways, for example, in Drosophila as well as case studies in non-classical animal models, have provided compelling evidence to challenge these views.Rather than comprehensively revisiting studies on the established genetic model systems of ageing, we here focus on an alternative model organism with a wild type (unselected genotype) characterized by a unique diversity in longevity - the honey bee.Honey bee (Apis mellifera) life span varies from a few weeks to more than 2 years. This plasticity is largely controlled by environmental factors. Thereby, although individuals are closely related genetically, distinct life histories can emerge as a function of social environmental change.Another remarkable feature of the honey bee is the occurrence of reverted behavioural ontogeny in the worker (female helper) caste. This behavioural peculiarity is associated with alterations in somatic maintenance functions that are indicative of reverted senescence. Thus, although intraspecific variation in organismal life span is not uncommon, the honey bee holds great promise for gaining insights into regulatory pathways that can shape the time-course of ageing by delaying, halting or even reversing processes of senescence. These aspects provide the setting of our review.We will highlight comparative findings from Drosophila melanogaster and Caenorhabditis elegans in particular, and focus on knowledge spanning from molecular- to behavioural-senescence to elucidate how the honey bee can contribute to novel insights into regulatory mechanisms that underlie plasticity and robustness or irreversibility in ageing.

Inducible knockdown of pregnancy-associated plasma protein-A gene expression in adult female mice extends life span.

PubMed

Bale, Laurie K; West, Sally A; Conover, Cheryl A

2017-08-01

Pregnancy-associated plasma protein-A (PAPP-A) knockout (KO) mice, generated through homologous recombination in embryonic stem cells, have a significantly increased lifespan compared to wild-type littermates. However, it is unknown whether this longevity advantage would pertain to PAPP-A gene deletion in adult animals. In the present study, we used tamoxifen (Tam)-inducible Cre recombinase-mediated excision of the floxed PAPP-A (fPAPP-A) gene in mice at 5 months of age. fPAPP-A mice, which were either positive (pos) or negative (neg) for Tam-Cre, received Tam treatment with quarterly boosters. Only female mice could be used with this experimental design. fPAPP-A/neg and fPAPP-A/pos mice had similar weights at the start of the experiment and showed equivalent weight gain. We found that fPAPP-A/pos mice had a significant extension of life span (P = 0.005). The median life span was increased by 21% for fPAPP-A/pos compared to fPAPP-A/neg mice. Analysis of mortality in life span quartiles indicated that the proportion of deaths of fPAPP-A/pos mice were lower than fPAPP-A/neg mice at young adult ages (P = 0.002 for 601-800 days) and higher than fPAPP-A/neg mice at older ages (P = 0.004 for >1000 days). Thus, survival curves and age-specific mortality indicate that female mice with knockdown of PAPP-A gene expression as adults have an extended healthy life span. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Dietary supplementation with Lovaza and krill oil shortens the life span of long-lived F1 mice.

PubMed

Spindler, Stephen R; Mote, Patricia L; Flegal, James M

2014-06-01

Marine oils rich in ω-3 polyunsaturated fatty acids have been recommended as a preventive treatment for patients at risk for cardiovascular diseases. These oils also are the third most consumed dietary supplement in the USA. However, evidence for their health benefits is equivocal. We tested the daily, isocaloric administration of krill oil (1.17 g oil/kg diet) and Lovaza (Omacor; 4.40 g/kg diet), a pharmaceutical grade fish oil, beginning at 12 months of age, on the life span and mortality-related pathologies of long-lived, male, B6C3F1 mice. The oils were incorporated into the chemically defined American Institute of Nutrition (AIN)-93 M diet. An equivalent volume of soybean oil was removed. Krill oil was 3 % and Lovaza 11 % of the oil in the diets. When their effects were analyzed together, the marine oils significantly shortened life span by 6.6 % (P = 0.0321; log-rank test) relative to controls. Individually, Lovaza and krill oil non-significantly shortened median life span by 9.8 and 4.7 %, respectively. Lovaza increased the number of enlarged seminal vesicles (7.1-fold). Lovaza and krill oil significantly increased lung tumors (4.1- and 8.2-fold) and hemorrhagic diathesis (3.9- and 3.1-fold). Analysis of serum from treated mice found that Lovaza slightly increased blood urea nitrogen, while krill oil modestly increased bilirubin, triglycerides, and blood glucose levels. Taken together, the results do not support the idea that the consumption of isolated ω-3 fatty acid-rich oils will increase the life span or health of initially healthy individuals.

Attachment and the Processing of Social Information across the Life Span: Theory and Evidence

ERIC Educational Resources Information Center

Dykas, Matthew J.; Cassidy, Jude

2011-01-01

Researchers have used J. Bowlby's (1969/1982, 1973, 1980, 1988) attachment theory frequently as a basis for examining whether experiences in close personal relationships relate to the processing of social information across childhood, adolescence, and adulthood. We present an integrative life-span-encompassing theoretical model to explain the…

Plant Reproduction. Plant Life in Action[TM]. Schlessinger Science Library. [Videotape].

ERIC Educational Resources Information Center

2000

Plants are vital to all other life on this planet - without them, there would be no food, shelter or oxygen. Luckily, over millions of years plants have developed many different features in order to survive and reproduce. In Plant Reproduction, students will discover that primitive mosses and algae are dependent upon water for their reproduction.…

Evaluation of Resveratrol, Green Tea Extract, Curcumin, Oxaloacetic Acid, and Medium-Chain Triglyceride Oil on Life Span of Genetically Heterogeneous Mice

PubMed Central

Miller, Richard A.; Astle, Clinton M.; Baur, Joseph A.; de Cabo, Rafael; Fernandez, Elizabeth; Guo, Wen; Javors, Martin; Kirkland, James L.; Nelson, James F.; Sinclair, David A.; Teter, Bruce; Williams, David; Zaveri, Nurulain; Nadon, Nancy L.; Harrison, David E.

2013-01-01

The National Institute on Aging Interventions Testing Program (ITP) was established to evaluate agents that are hypothesized to increase life span and/or health span in genetically heterogeneous mice. Each compound is tested in parallel at three test sites. It is the goal of the ITP to publish all results, negative or positive. We report here on the results of lifelong treatment of mice, beginning at 4 months of age, with each of five agents, that is, green tea extract (GTE), curcumin, oxaloacetic acid, medium-chain triglyceride oil, and resveratrol, on the life span of genetically heterogeneous mice. Each agent was administered beginning at 4 months of age. None of these five agents had a statistically significant effect on life span of male or female mice, by log-rank test, at the concentrations tested, although a secondary analysis suggested that GTE might diminish the risk of midlife deaths in females only. PMID:22451473

Self-esteem development across the life span: a longitudinal study with a large sample from Germany.

PubMed

Orth, Ulrich; Maes, Jürgen; Schmitt, Manfred

2015-02-01

The authors examined the development of self-esteem across the life span. Data came from a German longitudinal study with 3 assessments across 4 years of a sample of 2,509 individuals ages 14 to 89 years. The self-esteem measure used showed strong measurement invariance across assessments and birth cohorts. Latent growth curve analyses indicated that self-esteem follows a quadratic trajectory across the life span, increasing during adolescence, young adulthood, and middle adulthood, reaching a peak at age 60 years, and then declining in old age. No cohort effects on average levels of self-esteem or on the shape of the trajectory were found. Moreover, the trajectory did not differ across gender, level of education, or for individuals who had lived continuously in West versus East Germany (i.e., the 2 parts of Germany that had been separate states from 1949 to 1990). However, the results suggested that employment status, household income, and satisfaction in the domains of work, relationships, and health contribute to a more positive life span trajectory of self-esteem. The findings have significant implications, because they call attention to developmental stages in which individuals may be vulnerable because of low self-esteem (such as adolescence and old age) and to factors that predict successful versus problematic developmental trajectories. PsycINFO Database Record (c) 2015 APA, all rights reserved.

Lifelong alpha-tocopherol supplementation increases the median life span of C57BL/6 mice in the cold but has only minor effects on oxidative damage.

PubMed

Selman, Colin; McLaren, Jane S; Mayer, Claus; Duncan, Jackie S; Collins, Andrew R; Duthie, Garry G; Redman, Paula; Speakman, John R

2008-02-01

The effects of dietary antioxidant supplementation on oxidative stress and life span are confused. We maintained C57BL/6 mice at 7 +/- 2 degrees C and supplemented their diet with alpha-tocopherol from 4 months of age. Supplementation significantly increased (p = 0.042) median life span by 15% (785 days, n = 44) relative to unsupplemented controls (682 days, n = 43) and also increased maximum life span (oldest 10%, p = 0.028). No sex or sex by treatment interaction effects were observed on life span, with treatment having no effect on resting or daily metabolic rate. Lymphocyte and hepatocyte oxidative DNA damage and hepatic lipid peroxidation were unaffected by supplementation, but hepatic oxidative DNA damage increased with age. Using a cDNA macroarray, genes associated with xenobiotic metabolism were significantly upregulated in the livers of female mice at 6 months of age (2 months supplementation). At 22 months of age (18 months supplementation) this response had largely abated, but various genes linked to the p21 signaling pathway were upregulated at this time. We suggest that alpha-tocopherol may initially be metabolized as a xenobiotic, potentially explaining why previous studies observe a life span extension generally when lifelong supplementation is initiated early in life. The absence of any significant effect on oxidative damage suggests that the life span extension observed was not mediated via any antioxidant properties of alpha-tocopherol. We propose that the life span extension observed following alpha-tocopherol supplementation may be mediated via upregulation of cytochrome p450 genes after 2 months of supplementation and/or upregulation of p21 signaling genes after 18 months of supplementation. However, these signaling pathways now require further investigation to establish their exact role in life span extension following alpha-tocopherol supplementation.

Reduced resistance to oxidative stress during reproduction as a cost of early-life stress.

PubMed

Zimmer, Cédric; Spencer, Karen A

2015-05-01

Stress exposure during early-life development can have long-term consequences for a variety of biological functions including oxidative stress. The link between early-life stress and oxidative balance is beginning to be explored and previous studies have focused on this link in adult non-breeding or immature individuals. However, as oxidative stress is considered as the main physiological mechanism underlying the trade-off between self-maintenance and investment in reproduction, it is necessary to look at the consequences of early-life stress on oxidative status during reproduction. Here, we investigated the effects of exposure to pre- and/or post-natal stress on oxidative balance during reproduction under benign or stressful environmental conditions in an avian model species, the Japanese quail. We determined total antioxidant status (TAS), total oxidant status (TOS) and resistance to a free-radical attack in individual exposed to pre-natal stress, post-natal stress or both and in control individuals exposed to none of the stressors. TAS levels decreased over time in all females that reproduced under stressful conditions. TOS decreased between the beginning and the end of reproductive period in pre-natal control females. In all females, resistance to a free-radical attack decreased over the reproductive event but this decrease was more pronounced in females from a pre-natal stress development. Our results suggest that pre-natal stress may be associated with a higher cost of reproduction in terms of oxidative stress. These results also confirm that early-life stress can be associated with both benefits and costs depending of the life-history stage or environmental context. Copyright © 2014 Elsevier Inc. All rights reserved.

The roles of the immune system in women's reproduction: evolutionary constraints and life history trade-offs.

PubMed

Abrams, Elizabeth T; Miller, Elizabeth M

2011-01-01

Life history theory posits that, as long as survival is assured, finite resources are available for reproduction, maintenance, and growth/storage. To maximize lifetime reproductive success, resources are subject to trade-offs both within individuals and between current and future investment. For women, reproducing is costly and time-consuming; the bulk of available resources must be allocated to reproduction at the expense of more flexible systems like immune function. When reproducing women contract infectious diseases, the resources required for immune activation can fundamentally shift the patterns of resource allocation. Adding to the complexity of the reproductive-immune trade-offs in women are the pleiotropic effects of many immune factors, which were modified to serve key roles in mammalian reproduction. In this review, we explore the complex intersections between immune function and female reproduction to situate proximate immunological processes within a life history framework. After a brief overview of the immune system, we discuss some important physiological roles of immune factors in women's reproduction and the conflicts that may arise when these factors must play dual roles. We then discuss the influence of reproductive-immune trade-offs on the patterning of lifetime reproductive success: (1) the effect of immune activation/infectious disease on the timing of life history events; (2) the role of the immune system, immune activation, and infectious disease on resource allocation within individual reproductive events, particularly pregnancy; and (3) the role of the immune system in shaping the offspring's patterns of future life history trade-offs. We close with a discussion of future directions in reproductive immunology for anthropologists. Copyright © 2011 Wiley Periodicals, Inc.

NAD⁺ repletion improves mitochondrial and stem cell function and enhances life span in mice.

PubMed

Zhang, Hongbo; Ryu, Dongryeol; Wu, Yibo; Gariani, Karim; Wang, Xu; Luan, Peiling; D'Amico, Davide; Ropelle, Eduardo R; Lutolf, Matthias P; Aebersold, Ruedi; Schoonjans, Kristina; Menzies, Keir J; Auwerx, Johan

2016-06-17

Adult stem cells (SCs) are essential for tissue maintenance and regeneration yet are susceptible to senescence during aging. We demonstrate the importance of the amount of the oxidized form of cellular nicotinamide adenine dinucleotide (NAD(+)) and its effect on mitochondrial activity as a pivotal switch to modulate muscle SC (MuSC) senescence. Treatment with the NAD(+) precursor nicotinamide riboside (NR) induced the mitochondrial unfolded protein response and synthesis of prohibitin proteins, and this rejuvenated MuSCs in aged mice. NR also prevented MuSC senescence in the mdx (C57BL/10ScSn-Dmd(mdx)/J) mouse model of muscular dystrophy. We furthermore demonstrate that NR delays senescence of neural SCs and melanocyte SCs and increases mouse life span. Strategies that conserve cellular NAD(+) may reprogram dysfunctional SCs and improve life span in mammals. Copyright © 2016, American Association for the Advancement of Science.

A structured population model suggests that long life and post-reproductive lifespan promote the evolution of cooperation.

PubMed

Ross, Caitlin; Rychtář, Jan; Rueppell, Olav

2015-03-21

Social organization correlates with longevity across animal taxa. This correlation has been explained by selection for longevity by social evolution. The reverse causality is also conceivable but has not been sufficiently considered. We constructed a simple, spatially structured population model of asexually reproducing individuals to study the effect of temporal life history structuring on the evolution of cooperation. Individuals employed fixed strategies of cooperation or defection towards all neighbours in a basic Prisoner's Dilemma paradigm. Individuals aged and transitioned through different life history stages asynchronously without migration. An individual's death triggered a reproductive event by one immediate neighbour. The specific neighbour was chosen probabilistically according to the cumulative payoff from all local interactions. Varying the duration of pre-reproductive, reproductive, and post-reproductive life history stages, long-term simulations allowed a systematic evaluation of the influence of the duration of these specific life history stages. Our results revealed complex interactions among the effects of the three basic life history stages and the benefit to defect. Overall, a long post-reproductive stage promoted the evolution of cooperation, while a prolonged pre-reproductive stage has a negative effect. In general, the total length of life also increased the probability of the evolution of cooperation. Thus, our specific model suggests that the timing of life history transitions and total duration of life history stages may affect the evolution of cooperative behaviour. We conclude that the causation of the empirically observed association of life expectancy and sociality may be more complex than previously realized. Copyright © 2015 Elsevier Ltd. All rights reserved.

A structured population model suggests that long life and post-reproductive lifespan promote the evolution of cooperation

PubMed Central

Ross, Caitlin; Rychtář, Jan; Rueppell, Olav

2015-01-01

Social organization correlates with longevity across animal taxa. This correlation has been explained by selection for longevity by social evolution. The reverse causality is also conceivable but has not been sufficiently considered. We constructed a simple, spatially structured population model of asexually reproducing individuals to study the effect of temporal life history structuring on the evolution of cooperation. Individuals employed fixed strategies of cooperation or defection towards all neighbours in a basic Prisoner’s Dilemma paradigm. Individuals aged and transitioned through different life history stages asynchronously without migration. An individual’s death triggered a reproductive event by one immediate neighbour. The specific neighbour was chosen probabilistically according to the cumulative payoff from all local interactions. Varying the duration of pre-reproductive, reproductive, and post-reproductive life history stages, long-term simulations allowed a systematic evaluation of the influence of the duration of these specific life history stages. Our results revealed complex interactions among the effects of the three basic life history stages and the benefit to defect. Overall, a long post-reproductive stage promoted the evolution of cooperation, while a prolonged pre-reproductive stage has a negative effect. In general, the total length of life also increased the probability of the evolution of cooperation. Thus, our specific model suggests that the timing of life history transitions and total duration of life history stages may affect the evolution of cooperative behaviour. We conclude that the causation of the empirically observed association of life expectancy and sociality may be more complex than previously realized. PMID:25637763

Photosynthetic thermotolerance of woody savanna species in China is correlated with leaf life span

PubMed Central

Zhang, Jiao-Lin; Poorter, L.; Hao, Guang-You; Cao, Kun-Fang

2012-01-01

Background and Aims Photosynthetic thermotolerance (PT) is important for plant survival in tropical and sub-tropical savannas. However, little is known about thermotolerance of tropical and sub-tropical wild plants and its association with leaf phenology and persistence. Longer-lived leaves of savanna plants may experience a higher risk of heat stress. Foliar Ca is related to cell integrity of leaves under stresses. In this study it is hypothesized that (1) species with leaf flushing in the hot-dry season have greater PT than those with leaf flushing in the rainy season; and (2) PT correlates positively with leaf life span, leaf mass per unit area (LMA) and foliar Ca concentration ([Ca]) across woody savanna species. Methods The temperature-dependent increase in minimum fluorescence was measured to assess PT, together with leaf dynamics, LMA and [Ca] for a total of 24 woody species differing in leaf flushing time in a valley-type savanna in south-west China. Key Results The PT of the woody savanna species with leaf flushing in the hot-dry season was greater than that of those with leaf flushing in the rainy season. Thermotolerance was positively associated with leaf life span and [Ca] for all species irrespective of the time of flushing. The associations of PT with leaf life span and [Ca] were evolutionarily correlated. Thermotolerance was, however, independent of LMA. Conclusions Chinese savanna woody species are adapted to hot-dry habitats. However, the current maximum leaf temperature during extreme heat stress (44·3 °C) is close to the critical temperature of photosystem II (45·2 °C); future global warming may increase the risk of heat damage to the photosynthetic apparatus of Chinese savanna species. PMID:22875810

Nup100 regulates Saccharomyces cerevisiae replicative life span by mediating the nuclear export of specific tRNAs

PubMed Central

Lord, Christopher L.; Ospovat, Ophir; Wente, Susan R.

2017-01-01

Nuclear pore complexes (NPCs), which are composed of nucleoporins (Nups) and regulate transport between the nucleus and cytoplasm, significantly impact the replicative life span (RLS) of Saccharomyces cerevisiae. We previously reported that deletion of the nonessential gene NUP100 increases RLS, although the molecular basis for this effect was unknown. In this study, we find that nuclear tRNA accumulation contributes to increased longevity in nup100Δ cells. Fluorescence in situ hybridization (FISH) experiments demonstrate that several specific tRNAs accumulate in the nuclei of nup100Δ mutants. Protein levels of the transcription factor Gcn4 are increased when NUP100 is deleted, and GCN4 is required for the elevated life spans of nup100Δ mutants, similar to other previously described tRNA export and ribosomal mutants. Northern blots indicate that tRNA splicing and aminoacylation are not significantly affected in nup100Δ cells, suggesting that Nup100 is largely required for nuclear export of mature, processed tRNAs. Distinct tRNAs accumulate in the nuclei of nup100Δ and msn5Δ mutants, while Los1-GFP nucleocytoplasmic shuttling is unaffected by Nup100. Thus, we conclude that Nup100 regulates tRNA export in a manner distinct from Los1 or Msn5. Together, these experiments reveal a novel Nup100 role in the tRNA life cycle that impacts the S. cerevisiae life span. PMID:27932586

Gains and Losses in Creative Personality as Perceived by Adults across the Life Span

ERIC Educational Resources Information Center

Hui, Anna N. N.; Yeung, Dannii Y.; Sue-Chan, Christina; Chan, Kara; Hui, Desmond C. K.; Cheng, Sheung-Tak

2014-01-01

In this study, we used a life span model to study the subjective perception of creative personality (CP) in emerging, young, middle-aged, and older Hong Kong Chinese adults. We also asked participants to estimate the approximate age by which people develop and lose CP across adulthood. We expected an interesting interplay between internalized age…

Extending the Human Life Span: An Exploratory Study of Pro- and Anti-Longevity Attitudes

ERIC Educational Resources Information Center

Kogan, Nathan; Tucker, Jennifer; Porter, Matthew

2011-01-01

Successful efforts by biologists to substantially increase the life span of non-human animals has raised the possibility of extrapolation to humans, which in turn has given rise to bioethical argumentation, pro and con. The present study converts these arguments into pro- and anti-longevity items on a questionnaire and examines the structure and…

Auditory Environment across the Life Span of Cochlear Implant Users: Insights from Data Logging

ERIC Educational Resources Information Center

Busch, Tobias; Vanpoucke, Filiep; van Wieringen, Astrid

2017-01-01

Purpose: We describe the natural auditory environment of people with cochlear implants (CIs), how it changes across the life span, and how it varies between individuals. Method: We performed a retrospective cross-sectional analysis of Cochlear Nucleus 6 CI sound-processor data logs. The logs were obtained from 1,501 people with CIs (ages 0-96…

Life stage dependent responses to desiccation risk in the annual killifish Nothobranchius wattersi.

PubMed

Grégoir, A F; Philippe, C; Pinceel, T; Reniers, J; Thoré, E S J; Vanschoenwinkel, B; Brendonck, L

2017-09-01

To assess whether the annual killifish Nothobranchius wattersi responds plastically to a desiccation risk and whether this response is life stage dependent, life-history traits such as maturation time, fecundity and life span were experimentally measured in N. wattersi that were subjected to a drop in water level either as juveniles, as adults or both as juveniles and adults. Fish that were exposed to simulated pool drying as juveniles did not show changes in reproductive output or life span. Adults reacted by doubling short term egg deposition at the cost of a shorter lifespan. Overall, these results suggest that annual fish species can use phenotypic plasticity to maximize their reproductive output when faced with early pond drying, but this response appears to be life-stage specific. In addition to frogs and aquatic insects, phenotypic plasticity induced by forthcoming drought is now also confirmed in annual fishes and could well be a common feature of the limited number of fish taxa that manage to survive in this extreme environment. © 2017 The Fisheries Society of the British Isles.

Developmental change in proactive interference across the life span: evidence from two working memory tasks.

PubMed

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

2014-04-01

Working memory (WM) as the ability to temporarily maintain and manipulate various kinds of information is known to be affected by proactive interference (PI) from previously relevant contents, but studies on developmental changes in the susceptibility to PI are scarce. In the present study, we investigated life span development of item-specific PI. To this end, 92 individuals between the ages of 8 and 74 years completed a recent-probes task and an n-back task that both composed experimental manipulations of PI. Regarding global WM development, young adults had higher WM performance than children and older adults in both tasks. Significant PI × Age interactions revealed that susceptibility to PI changed over the life span in both tasks, whereas the developmental course of PI differed between the tasks: Children committed more PI-related errors than young adults in the recent-probes task but showed marginally less PI in the n-back task. Regarding reaction time costs, children did not differ from adults in the recent-probes task and were less affected than adults in the n-back. Older adults showed more PI-related errors than young adults in both tasks. Therefore, as expected, item-specific PI changed over the life span with the young adults being less susceptible to PI than children and older adults. The diverging developmental effects of PI across both tasks, especially in the children, are supposed to reflect different causes for the difficulties regarding resisting PI in children and older adults. These might concern differently developed underlying cognitive processes such as inhibition or recollection, or different responses to task demands across both tasks. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Relationships of leaf dark respiration to leaf nitrogen, specific leaf area and leaf life-span: a test across biomes and functional groups.

PubMed

Reich, Peter B; Walters, Michael B; Ellsworth, David S; Vose, James M; Volin, John C; Gresham, Charles; Bowman, William D

1998-05-01

Based on prior evidence of coordinated multiple leaf trait scaling, we hypothesized that variation among species in leaf dark respiration rate (R d ) should scale with variation in traits such as leaf nitrogen (N), leaf life-span, specific leaf area (SLA), and net photosynthetic capacity (A max ). However, it is not known whether such scaling, if it exists, is similar among disparate biomes and plant functional types. We tested this idea by examining the interspecific relationships between R d measured at a standard temperature and leaf life-span, N, SLA and A max for 69 species from four functional groups (forbs, broad-leafed trees and shrubs, and needle-leafed conifers) in six biomes traversing the Americas: alpine tundra/subalpine forest, Colorado; cold temperate forest/grassland, Wisconsin; cool temperate forest, North Carolina; desert/shrubland, New Mexico; subtropical forest, South Carolina; and tropical rain forest, Amazonas, Venezuela. Area-based R d was positively related to area-based leaf N within functional groups and for all species pooled, but not when comparing among species within any site. At all sites, mass-based R d (R d-mass ) decreased sharply with increasing leaf life-span and was positively related to SLA and mass-based A max and leaf N (leaf N mass ). These intra-biome relationships were similar in shape and slope among sites, where in each case we compared species belonging to different plant functional groups. Significant R d-mass -N mass relationships were observed in all functional groups (pooled across sites), but the relationships differed, with higher R d at any given leaf N in functional groups (such as forbs) with higher SLA and shorter leaf life-span. Regardless of biome or functional group, R d-mass was well predicted by all combinations of leaf life-span, N mass and/or SLA (r 2 ≥ 0.79, P < 0.0001). At any given SLA, R d-mass rises with increasing N mass and/or decreasing leaf life-span; and at any level of N mass , R d

Proteotoxicity and the contrasting effects of oxaloacetate and glycerol on Caenorhabditis elegans life span: a role for methylglyoxal?

PubMed

Hipkiss, Alan R

2010-10-01

Because accumulation of altered proteins is the most common biochemical symptom of aging, it is at least possible that such proteotoxicity may cause aging and influence life span. The life span of the nematode worm Caenorhabditis elegans is strongly influenced by changes in the intracellular concentration of methylglyoxal (MG), a putative source of much age-related proteotoxicity and organelle, cellular, and molecular dysfunction. Glycerol has recently been shown to shorten, whereas oxaloacetate has been found to extend, life span in C. elegans. It is suggested here that glycerol and oxaloacetate exert opposing effects on MG formation in C. elegans. It is proposed that, if not secreted by aquaporin, glycerol is converted to glycerol phosphate and then to dihydroxyacetone phosphate (DHAP) via a reaction requiring nicotinamide adenine dinucleotide (NAD(+)). This inhibits operation of the glycerol phosphate cycle in which DHAP is converted into glycerol phosphate, which concomitantly regenerates NAD(+) from NADH, thereby ensuring glycolytic oxidation of glyceraldehyde-3-phosphate (G3P). Because DHAP and G3P spontaneously decompose into MG, and NAD(+) is required for conversion of G3P into phosphoglycerate, the glycerol-induced increased DHAP formation and decreased NAD(+) availability will increase the potential for MG generation. In contrast, oxaloacetate may decrease MG generation by stimulating the operation of the malate-oxaloacetate shuttle, in which oxaloacetate is converted to malate, which regenerates NAD(+) from NADH. By the ensuing G3P oxidation, increased NAD(+) availability will decrease the potential for MG formation. It should be noted that mitochondria are involved in the operation of the above cycle/shuttles and that increased NAD(+) availability also stimulates those sirtuin activities that increase mitogenesis and mitochondrial activity via effects on signal transduction and gene expression, which frequently accompany dietary restriction-induced life

Nup100 regulates Saccharomyces cerevisiae replicative life span by mediating the nuclear export of specific tRNAs.

PubMed

Lord, Christopher L; Ospovat, Ophir; Wente, Susan R

2017-03-01

Nuclear pore complexes (NPCs), which are composed of nucleoporins (Nups) and regulate transport between the nucleus and cytoplasm, significantly impact the replicative life span (RLS) of Saccharomyces cerevisiae We previously reported that deletion of the nonessential gene NUP100 increases RLS, although the molecular basis for this effect was unknown. In this study, we find that nuclear tRNA accumulation contributes to increased longevity in nup100 Δ cells. Fluorescence in situ hybridization (FISH) experiments demonstrate that several specific tRNAs accumulate in the nuclei of nup100 Δ mutants. Protein levels of the transcription factor Gcn4 are increased when NUP100 is deleted, and GCN4 is required for the elevated life spans of nup100 Δ mutants, similar to other previously described tRNA export and ribosomal mutants. Northern blots indicate that tRNA splicing and aminoacylation are not significantly affected in nup100 Δ cells, suggesting that Nup100 is largely required for nuclear export of mature, processed tRNAs. Distinct tRNAs accumulate in the nuclei of nup100 Δ and msn5 Δ mutants, while Los1-GFP nucleocytoplasmic shuttling is unaffected by Nup100. Thus, we conclude that Nup100 regulates tRNA export in a manner distinct from Los1 or Msn5. Together, these experiments reveal a novel Nup100 role in the tRNA life cycle that impacts the S. cerevisiae life span. © 2017 Lord et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

Life history context of reproductive aging in a wild primate model

PubMed Central

Altmann, Jeanne; Gesquiere, Laurence; Galbany, Jordi; Onyango, Patrick O.; Alberts, Susan C.

2012-01-01

The pace of reproductive aging has been of considerable interest, especially in regard to the long postreproductive period in modern women. Here we use data for both sexes from a 37-year longitudinal study of a wild baboon population to place reproductive aging within a life history context for this species, a primate relative of humans that evolved in the same savannah habitat as humans did. We examine the patterns and pace of reproductive aging, including birth rates and reproductive hormones for both sexes, and compare reproductive aging to age-related changes in several other traits. Reproductive senescence occurs later in baboon females than males. Delayed senescence in females relative to males is also found in several other traits, such as dominance status and body condition, but not in molar wear or glucocorticoid profiles. Survival, health, and well-being are the product of risk factors in morphological, physiological, and behavioral traits that differ in rate of senescence and in dependence on social or ecological conditions; some will be very sensitive to differences in circumstances and others less so. PMID:20738283

Basic traits predict the prevalence of personality disorder across the life span: the example of psychopathy.

PubMed

Vachon, David D; Lynam, Donald R; Widiger, Thomas A; Miller, Joshua D; McCrae, Robert R; Costa, Paul T

2013-05-01

Personality disorders (PDs) may be better understood in terms of dimensions of general personality functioning rather than as discrete categorical conditions. Personality-trait descriptions of PDs are robust across methods and settings, and PD assessments based on trait measures show good construct validity. The study reported here extends research showing that basic traits (e.g., impulsiveness, warmth, straightforwardness, modesty, and deliberation) can re-create the epidemiological characteristics associated with PDs. Specifically, we used normative changes in absolute trait levels to simulate age-related differences in the prevalence of psychopathy in a forensic setting. Results demonstrated that trait information predicts the rate of decline for psychopathy over the life span; discriminates the decline of psychopathy from that of a similar disorder, antisocial PD; and accurately predicts the differential decline of subfactors of psychopathy. These findings suggest that basic traits provide a parsimonious account of PD prevalence across the life span.

Developmental Change in Proactive Interference across the Life Span: Evidence from Two Working Memory Tasks

ERIC Educational Resources Information Center

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

2014-01-01

Working memory (WM) as the ability to temporarily maintain and manipulate various kinds of information is known to be affected by proactive interference (PI) from previously relevant contents, but studies on developmental changes in the susceptibility to PI are scarce. In the present study, we investigated life span development of item-specific…

Stochastic variation in telomere shortening rate causes heterogeneity of human fibroblast replicative life span.

PubMed

Martin-Ruiz, Carmen; Saretzki, Gabriele; Petrie, Joanne; Ladhoff, Juliane; Jeyapalan, Jessie; Wei, Wenyi; Sedivy, John; von Zglinicki, Thomas

2004-04-23

The replicative life span of human fibroblasts is heterogeneous, with a fraction of cells senescing at every population doubling. To find out whether this heterogeneity is due to premature senescence, i.e. driven by a nontelomeric mechanism, fibroblasts with a senescent phenotype were isolated from growing cultures and clones by flow cytometry. These senescent cells had shorter telomeres than their cycling counterparts at all population doubling levels and both in mass cultures and in individual subclones, indicating heterogeneity in the rate of telomere shortening. Ectopic expression of telomerase stabilized telomere length in the majority of cells and rescued them from early senescence, suggesting a causal role of telomere shortening. Under standard cell culture conditions, there was a minor fraction of cells that showed a senescent phenotype and short telomeres despite active telomerase. This fraction increased under chronic mild oxidative stress, which is known to accelerate telomere shortening. It is possible that even high telomerase activity cannot fully compensate for telomere shortening in all cells. The data show that heterogeneity of the human fibroblast replicative life span can be caused by significant stochastic cell-to-cell variation in telomere shortening.

Expert Panel Recommendations on Lower Urinary Tract Health of Women Across Their Life Span

PubMed Central

Losada, Liliana; Amundsen, Cindy L.; Ashton-Miller, James; Chai, Toby; Close, Clare; Damaser, Margot; DiSanto, Michael; Dmochowski, Roger; Fraser, Matthew O.; Kielb, Stephanie J.; Kuchel, George; Mueller, Elizabeth R.; Parker-Autry, Candace; Wolfe, Alan J.

2016-01-01

Abstract Urologic and kidney problems are common in women across their life span and affect their daily life, including physical activity, sexual relations, social life, and future health. Urological health in women is still understudied and the underlying mechanisms of female urological dysfunctions are not fully understood. The Society for Women's Health Research (SWHR®) recognized the need to have a roundtable discussion where researchers and clinicians would define the current state of knowledge, gaps, and recommendations for future research directions to transform women's urological health. This report summarizes the discussions, which focused on epidemiology, clinical presentation, basic science, prevention strategies, and efficacy of current therapies. Experts around the table agreed on a set of research, education, and policy recommendations that have the potential to dramatically increase awareness and improve women's urological health at all stages of life. PMID:27285829

The primacy of primary control is a human universal: a reply to Gould's (1999) critique of the life-span theory of control.

PubMed

Heckhausen, J; Schulz, R

1999-07-01

This reply to S. J. Gould's (1999) critique of J. Heckhausen and R. Schulz's (1995) life-span theory of control addresses four issues: (1) the universal claim that primary control holds functional primacy over secondary control, (2) the status of secondary control as a confederate to primary control, (3) empirical evidence and paradigms for investigating universality and cultural variations, and (4) the capacity of the human control system to manage both gains and losses in control throughout the life span and aging-related decline in particular. Theoretical perspectives and empirical evidence from evolutionary, comparative, developmental, and cultural psychology are presented to support the authors' view that primary control striving holds functional primacy throughout the life span and across cultural and historical settings. Recommendations for empirically investigating the variations in the way primary control striving is expressed in different cultures are outlined.

Telomerase-mediated life-span extension of human primary fibroblasts by human artificial chromosome (HAC) vector

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shitara, Shingo; Kakeda, Minoru; Nagata, Keiko

2008-05-09

Telomerase-mediated life-span extension enables the expansion of normal cells without malignant transformation, and thus has been thought to be useful in cell therapies. Currently, integrating vectors including the retrovirus are used for human telomerase reverse transcriptase (hTERT)-mediated expansion of normal cells; however, the use of these vectors potentially causes unexpected insertional mutagenesis and/or activation of oncogenes. Here, we established normal human fibroblast (hPF) clones retaining non-integrating human artificial chromosome (HAC) vectors harboring the hTERT expression cassette. In hTERT-HAC/hPF clones, we observed the telomerase activity and the suppression of senescent-associated SA-{beta}-galactosidase activity. Furthermore, the hTERT-HAC/hPF clones continued growing beyond 120 daysmore » after cloning, whereas the hPF clones retaining the silent hTERT-HAC senesced within 70 days. Thus, hTERT-HAC-mediated episomal expression of hTERT allows the extension of the life-span of human primary cells, implying that gene delivery by non-integrating HAC vectors can be used to control cellular proliferative capacity of primary cultured cells.« less

Early-life reproduction is associated with increased mortality risk but enhanced lifetime fitness in pre-industrial humans

PubMed Central

Hayward, Adam D.; Nenko, Ilona; Lummaa, Virpi

2015-01-01

The physiology of reproductive senescence in women is well understood, but the drivers of variation in senescence rates are less so. Evolutionary theory predicts that early-life investment in reproduction should be favoured by selection at the cost of reduced survival and faster reproductive senescence. We tested this hypothesis using data collected from preindustrial Finnish church records. Reproductive success increased up to age 25 and was relatively stable until a decline from age 41. Women with higher early-life fecundity (ELF; producing more children before age 25) subsequently had higher mortality risk, but high ELF was not associated with accelerated senescence in annual breeding success. However, women with higher ELF experienced faster senescence in offspring survival. Despite these apparent costs, ELF was under positive selection: individuals with higher ELF had higher lifetime reproductive success. These results are consistent with previous observations in both humans and wild vertebrates that more births and earlier onset of reproduction are associated with reduced survival, and with evolutionary theory predicting trade-offs between early reproduction and later-life survival. The results are particularly significant given recent increases in maternal ages in many societies and the potential consequences for offspring health and fitness. PMID:25740893

Caloric restriction: Impact upon pituitary function and reproduction

PubMed Central

Martin, Bronwen; Golden, Erin; Carlson, Olga D.; Egan, Josephine M.; Mattson, Mark P.; Maudsley, Stuart

2008-01-01

Reduced energy intake, or caloric restriction (CR), is known to extend life span and to retard age-related health decline in a number of different species, including worms, flies, fish, mice and rats. CR has been shown to reduce oxidative stress, improve insulin sensitivity, and alter neuroendocrine responses and central nervous system (CNS) function in animals. CR has particularly profound and complex actions upon reproductive health. At the reductionist level the most crucial physiological function of any organism is its capacity to reproduce. For a successful species to thrive, the balance between available energy (food) and the energy expenditure required for reproduction must be tightly linked. An ability to coordinate energy balance and fecundity involves complex interactions of hormones from both the periphery and the CNS and primarily centers upon the master endocrine gland, the anterior pituitary. In this review article we review the effects of CR on pituitary gonadotrope function and on the male and female reproductive axes. A better understanding of how dietary energy intake affects reproductive axis function and endocrine pulsatility could provide novel strategies for the prevention and management of reproductive dysfunction and its associated comorbidities. PMID:18329344

Reproductive Life Planning: A Cross-Sectional Study of What College Students Know and Believe.

PubMed

Kransdorf, Lisa N; Raghu, T S; Kling, Juliana M; David, Paru S; Vegunta, Suneela; Knatz, Jo; Markus, Allan; Frey, Keith A; Chang, Yu-Hui H; Mayer, Anita P; Files, Julia A

2016-06-01

Objectives The Centers for Disease Control and Prevention recommends a reproductive life plan (RLP) to promote individual responsibility for preconception health. The objectives of this study were to determine existing awareness of RLPs in a cohort of reproductive-age adults and to evaluate their knowledge level and beliefs about reproductive life planning. Methods We performed a cross-sectional survey study of adults ages 18-40 years old seeking care at the student health center of a large public university. Participation was voluntary. Survey responses were analyzed by age and gender. Results A total of 559 surveys were collected and analyzed. Only 24 % of participants had heard of an RLP although a majority (62.9 %) agreed that it is important to develop an RLP. Most respondents (85.4 %) preferred to receive information about reproductive life planning from a primary care provider or obstetrician-gynecologist, while only 4.2 % of patients surveyed reported ever being actually asked about an RLP by their healthcare provider. Among those who agreed that an RLP was important, knowledge of specific aspects of an RLP was lacking. Conclusions In our cohort of reproductive-age adults, general health literacy regarding RLPs was poor. Most of the young adults who responded to our survey did not know what an RLP was and even fewer had ever discussed one with their health provider.

The Years of Uncertainty: Eighth Grade Family Life Education.

ERIC Educational Resources Information Center

Carson, Mary, Ed.; And Others

The family life sex education unit for eighth graders, "The Years of Uncertainty," consists of a series of daily lesson plans that span a 29-day period of one-hour class sessions. Topics covered are: problem solving, knowledge and attitudes, male and female reproductive systems, conception, pregnancy, birth, birth defects, venereal…

Primate energy expenditure and life history

PubMed Central

Pontzer, Herman; Raichlen, David A.; Gordon, Adam D.; Schroepfer-Walker, Kara K.; Hare, Brian; O’Neill, Matthew C.; Muldoon, Kathleen M.; Dunsworth, Holly M.; Wood, Brian M.; Isler, Karin; Burkart, Judith; Irwin, Mitchell; Shumaker, Robert W.; Lonsdorf, Elizabeth V.; Ross, Stephen R.

2014-01-01

Humans and other primates are distinct among placental mammals in having exceptionally slow rates of growth, reproduction, and aging. Primates’ slow life history schedules are generally thought to reflect an evolved strategy of allocating energy away from growth and reproduction and toward somatic investment, particularly to the development and maintenance of large brains. Here we examine an alternative explanation: that primates’ slow life histories reflect low total energy expenditure (TEE) (kilocalories per day) relative to other placental mammals. We compared doubly labeled water measurements of TEE among 17 primate species with similar measures for other placental mammals. We found that primates use remarkably little energy each day, expending on average only 50% of the energy expected for a placental mammal of similar mass. Such large differences in TEE are not easily explained by differences in physical activity, and instead appear to reflect systemic metabolic adaptation for low energy expenditures in primates. Indeed, comparisons of wild and captive primate populations indicate similar levels of energy expenditure. Broad interspecific comparisons of growth, reproduction, and maximum life span indicate that primates’ slow metabolic rates contribute to their characteristically slow life histories. PMID:24474770

Evidence for a relationship between longevity of mammalian species and life spans of normal fibroblasts in vitro and erythrocytes in vivo

PubMed Central

Röhme, Dan

1981-01-01

The replicative life spans of mammalian fibroblasts in vitro were studied in a number of cell cultures representing eight species. Emphasis was placed on determining the population doubling level at which phase III (a period of decrease in the rate of proliferation) and chromosomal alterations occur. All the cell cultures studied went through a growth crisis, a period of apparent growth cessation lasting for at least 2 weeks. In most cultures, the crisis represented the end of their replicative capacities, but in some cultures cell proliferation was resumed after the crisis. A predominantly diploid chromosome constitution (more than 75%) was demonstrated prior to the growth crisis. In cultures in which cell proliferation was resumed after the crisis, a nondiploid constitution prevailed in all cases except the rat (with 90% or more diploid cells all the time). The growth crisis occurred at population doubling levels that were characteristic for the species and was shown to be related to the species' maximal life span by a strict power law, being proportional to the square root of the maximal life span. Based on data in the literature, the same relationship was also valid for the lifespans of circulating mammalian erythrocytes in vivo. These results may indicate the prevalence of a common functional basis regulating the life span of fibroblasts and erythrocytes and thus operating in replicative as well as postmitotic cells in vitro and in vivo. PMID:6946449

Age Differences and Educational Attainment across the Life Span on Three Generations of Wechsler Adult Scales

ERIC Educational Resources Information Center

Kaufman, A. S.; Salthouse, T. A.; Scheiber, C.; Chen, H.

2016-01-01

Patterns of maintenance of ability across the life span have been documented on tests of knowledge ("Gc"), as have patterns of steady decline on measures of reasoning ("Gf/Gv"), working memory ("Gsm"), and speed ("Gs"). Whether these patterns occur at the same rate for adults from different educational…

Age differences in five personality domains across the life span.

PubMed

Allemand, Mathias; Zimprich, Daniel; Hendriks, A A Jolijn

2008-05-01

The present study addresses the issue of age differences in 5 personality domains across the life span in a cross-sectional study. In contrast to most previous studies, the present study follows a methodologically more rigorous approach to warrant that age-related differences in personality structure and mean level can be meaningfully compared. It uses data on 50 items of the Five-Factor Personality Inventory (FFPI) available from a study in a large and representative Dutch sample (N = 2,494; age range: 16 to 91 years) conducted in 1996 for the purpose of establishing norms for the FFPI. After having established strict measurement invariance, tests were made for factor covariances to be equal across age groups, revealing structural continuity of personality. Additionally, factor variances were shown to be equal across age groups. A number of age differences in the mean level of the five personality domains emerged. Specifically, older adults were, on average, more agreeable and, especially, more conscientious than middle-aged and younger adults. Findings from our study suggest that both continuity and change may mark personality over the course of life. (PsycINFO Database Record (c) 2008 APA, all rights reserved).

Divergent patterns of age-dependence in ornamental and reproductive traits in the collared flycatcher.

PubMed

Evans, Simon R; Gustafsson, Lars; Sheldon, Ben C

2011-06-01

Sexual ornaments are predicted to honestly signal individual condition. We might therefore expect ornament expression to show a senescent decline, in parallel with late-life deterioration of other characters. Conversely, life-history theory predicts the reduced residual reproductive value of older individuals will favor increased investment in sexually attractive traits. Using a 25-year dataset of more than 5000 records of breeding collared flycatchers (Ficedula albicollis) of known age, we quantify cross-sectional patterns of age-dependence in ornamental plumage traits and report long-term declines in expression that mask highly significant positive age-dependency. We partition this population-level age-dependency into its between- and within-individual components and show expression of ornamental white plumage patches exhibits within-individual increases with age in both sexes, consistent with life-history theory. For males, ornament expression also covaries with life span, such that, within a cohort, ornamentation indicates survival. Finally, we compared longitudinal age-dependency of reproductive traits and ornamental traits in both sexes, to assess whether these two trait types exhibit similar age-dependency. These analyses revealed contrasting patterns: reproductive traits showed within-individual declines in late-life females consistent with senescence; ornamental traits showed the opposite pattern in both males and females. Hence, our results for both sexes suggest that age-dependent ornament expression is consistent with life-history models of optimal signaling and, unlike reproductive traits, proof against senescence. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

Dissociable Changes of Frontal and Parietal Cortices in Inherent Functional Flexibility across the Human Life Span.

PubMed

Yin, Dazhi; Liu, Wenjing; Zeljic, Kristina; Wang, Zhiwei; Lv, Qian; Fan, Mingxia; Cheng, Wenhong; Wang, Zheng

2016-09-28

Extensive evidence suggests that frontoparietal regions can dynamically update their pattern of functional connectivity, supporting cognitive control and adaptive implementation of task demands. However, it is largely unknown whether this flexibly functional reconfiguration is intrinsic and occurs even in the absence of overt tasks. Based on recent advances in dynamics of resting-state functional resonance imaging (fMRI), we propose a probabilistic framework in which dynamic reconfiguration of intrinsic functional connectivity between each brain region and others can be represented as a probability distribution. A complexity measurement (i.e., entropy) was used to quantify functional flexibility, which characterizes heterogeneous connectivity between a particular region and others over time. Following this framework, we identified both functionally flexible and specialized regions over the human life span (112 healthy subjects from 13 to 76 years old). Across brainwide regions, we found regions showing high flexibility mainly in the higher-order association cortex, such as the lateral prefrontal cortex (LPFC), lateral parietal cortex, and lateral temporal lobules. In contrast, visual, auditory, and sensory areas exhibited low flexibility. Furthermore, we observed that flexibility of the right LPFC improved during maturation and reduced due to normal aging, with the opposite occurring for the left lateral parietal cortex. Our findings reveal dissociable changes of frontal and parietal cortices over the life span in terms of inherent functional flexibility. This study not only provides a new framework to quantify the spatiotemporal behavior of spontaneous brain activity, but also sheds light on the organizational principle behind changes in brain function across the human life span. Recent neuroscientific research has demonstrated that the human capability of adaptive task control is primarily the result of the flexible operation of frontal brain networks. However

Evolution of reproductive life histories in island birds worldwide

PubMed Central

Covas, Rita

2012-01-01

Island environments typically share characteristics such as impoverished biotas and less-seasonal climates, which should be conducive to specific adaptations by organisms. However, with the exception of morphological studies, broad-scale tests of patterns of adaptation on islands are rare. Here, I examine reproductive patterns in island birds worldwide. Reproductive life histories are influenced by latitude, which could affect the response to insularity; therefore, I additionally test this hypothesis. Island colonizers showed mostly bi-parental care, but there was a significant increase in cooperative breeding on islands. Additionally, I found support for previous suggestions of reduced fecundity, longer developmental periods and increased investment in young on islands. However, clutch size increased with latitude at a rate nearly five times faster on the mainland than on the islands revealing a substantially stronger effect of insularity at higher latitudes. Latitude and insularity may also interact to determine egg volume and incubation periods, but these effects were less clear. Analyses of reproductive success did not support an effect of reduced nest predation as a driver of reproductive change, but this requires further study. The effect of latitude detected here suggests that the evolutionary changes associated with insularity relate to environmental stability and improved adult survival. PMID:22072609

A cost–benefit analysis of acclimation to low irradiance in tropical rainforest tree seedlings: leaf life span and payback time for leaf deployment

PubMed Central

Coste, Sabrina; Roggy, Jean-Christophe; Schimann, Heidy; Epron, Daniel; Dreyer, Erwin

2011-01-01

The maintenance in the long run of a positive carbon balance under very low irradiance is a prerequisite for survival of tree seedlings below the canopy or in small gaps in a tropical rainforest. To provide a quantitative basis for this assumption, experiments were carried out to determine whether construction cost (CC) and payback time for leaves and support structures, as well as leaf life span (i) differ among species and (ii) display an irradiance-elicited plasticity. Experiments were also conducted to determine whether leaf life span correlates to CC and payback time and is close to the optimal longevity derived from an optimization model. Saplings from 13 tropical tree species were grown under three levels of irradiance. Specific-CC was computed, as well as CC scaled to leaf area at the metamer level. Photosynthesis was recorded over the leaf life span. Payback time was derived from CC and a simple photosynthesis model. Specific-CC displayed only little interspecific variability and irradiance-elicited plasticity, in contrast to CC scaled to leaf area. Leaf life span ranged from 4 months to >26 months among species, and was longest in seedlings grown under lowest irradiance. It was always much longer than payback time, even under the lowest irradiance. Leaves were shed when their photosynthesis had reached very low values, in contrast to what was predicted by an optimality model. The species ranking for the different traits was stable across irradiance treatments. The two pioneer species always displayed the smallest CC, leaf life span, and payback time. All species displayed a similar large irradiance-elicited plasticity. PMID:21511904

Early-life reproduction is associated with increased mortality risk but enhanced lifetime fitness in pre-industrial humans.

PubMed

Hayward, Adam D; Nenko, Ilona; Lummaa, Virpi

2015-04-07

The physiology of reproductive senescence in women is well understood, but the drivers of variation in senescence rates are less so. Evolutionary theory predicts that early-life investment in reproduction should be favoured by selection at the cost of reduced survival and faster reproductive senescence. We tested this hypothesis using data collected from preindustrial Finnish church records. Reproductive success increased up to age 25 and was relatively stable until a decline from age 41. Women with higher early-life fecundity (ELF; producing more children before age 25) subsequently had higher mortality risk, but high ELF was not associated with accelerated senescence in annual breeding success. However, women with higher ELF experienced faster senescence in offspring survival. Despite these apparent costs, ELF was under positive selection: individuals with higher ELF had higher lifetime reproductive success. These results are consistent with previous observations in both humans and wild vertebrates that more births and earlier onset of reproduction are associated with reduced survival, and with evolutionary theory predicting trade-offs between early reproduction and later-life survival. The results are particularly significant given recent increases in maternal ages in many societies and the potential consequences for offspring health and fitness. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Delayed accumulation of intestinal coliform bacteria enhances life span and stress resistance in Caenorhabditis elegans fed respiratory deficient E. coli.

PubMed

Gomez, Fernando; Monsalve, Gabriela C; Tse, Vincent; Saiki, Ryoichi; Weng, Emily; Lee, Laura; Srinivasan, Chandra; Frand, Alison R; Clarke, Catherine F

2012-12-20

Studies with the nematode model Caenorhabditis elegans have identified conserved biochemical pathways that act to modulate life span. Life span can also be influenced by the composition of the intestinal microbiome, and C. elegans life span can be dramatically influenced by its diet of Escherichia coli. Although C. elegans is typically fed the standard OP50 strain of E. coli, nematodes fed E. coli strains rendered respiratory deficient, either due to a lack coenzyme Q or the absence of ATP synthase, show significant life span extension. Here we explore the mechanisms accounting for the enhanced nematode life span in response to these diets. The intestinal load of E. coli was monitored by determination of worm-associated colony forming units (cfu/worm or coliform counts) as a function of age. The presence of GFP-expressing E. coli in the worm intestine was also monitored by fluorescence microscopy. Worms fed the standard OP50 E. coli strain have high cfu and GFP-labeled bacteria in their guts at the L4 larval stage, and show saturated coliform counts by day five of adulthood. In contrast, nematodes fed diets of respiratory deficient E. coli lacking coenzyme Q lived significantly longer and failed to accumulate bacteria within the lumen at early ages. Animals fed bacteria deficient in complex V showed intermediate coliform numbers and were not quite as long-lived. The results indicate that respiratory deficient Q-less E. coli are effectively degraded in the early adult worm, either at the pharynx or within the intestine, and do not accumulate in the intestinal tract until day ten of adulthood. The findings of this study suggest that the nematodes fed the respiratory deficient E. coli diet live longer because the delay in bacterial colonization of the gut subjects the worms to less stress compared to worms fed the OP50 E. coli diet. This work suggests that bacterial respiration can act as a virulence factor, influencing the ability of bacteria to colonize and

Effects of salinity on egg and fecal pellet production, development and survival, adult sex ratio and total life span in the calanoid copepod, Acartia tonsa: a laboratory study

NASA Astrophysics Data System (ADS)

Shayegan, Majid; Esmaeili Fereidouni, Abolghasem; Agh, Naser; Jani Khalili, Khosrow

2016-07-01

The effects of salinity on the copepod, Acartia tonsa in terms of daily egg production rate (EPR), hatching success, fecal pellet production rate (FPR), naupliar development time and survival, sex ratio, and total life span were determined in laboratory conditions through three experiments. In experiment 1, EPR, hatching success, and FPR of individual females were monitored at salinities of 13, 20, 35 and 45 during short-periods (seven consecutive days). Results show EPR was affected by salinity with the highest outputs recorded at 20 and 35, respectively, which were considerably higher than those at 13 and 45. Mean FPR was also higher in 35 and 20. In experiment 2, the same parameters were evaluated over total life span of females (long-term study). The best EPR and FPR were observed in 35, which was statistically higher than at 13 and 20. In experiment 3, survival rates of early nauplii until adult stage were lowest at a salinity of 13. The development time increased with increasing of salinity. Female percentage clearly decreased with increasing salinity. Higher female percentages (56.7% and 52.2%, respectively) were significantly observed at two salinities of 13 and 20 compared to that at 35 (25%). Total longevity of females was not affected by salinity increment. Based on our results, for mass culture we recommend that a salinity of 35 be adopted due to higher reproductive performances, better feeding, and faster development of A. tonsa.

The development of memory efficiency and value-directed remembering across the life span: a cross-sectional study of memory and selectivity.

PubMed

Castel, Alan D; Humphreys, Kathryn L; Lee, Steve S; Galván, Adriana; Balota, David A; McCabe, David P

2011-11-01

Although attentional control and memory change considerably across the life span, no research has examined how the ability to strategically remember important information (i.e., value-directed remembering) changes from childhood to old age. The present study examined this in different age groups across the life span (N = 320, 5-96 years old). A selectivity task was used in which participants were asked to study and recall items worth different point values in order to maximize their point score. This procedure allowed for measures of memory quantity/capacity (number of words recalled) and memory efficiency/selectivity (the recall of high-value items relative to low-value items). Age-related differences were found for memory capacity, as young adults recalled more words than the other groups. However, in terms of selectivity, younger and older adults were more selective than adolescents and children. The dissociation between these measures across the life span illustrates important age-related differences in terms of memory capacity and the ability to selectively remember high-value information.

Circadian clocks govern calorie restriction-mediated life span extension through BMAL1- and IGF-1-dependent mechanisms.

PubMed

Patel, Sonal A; Chaudhari, Amol; Gupta, Richa; Velingkaar, Nikkhil; Kondratov, Roman V

2016-04-01

Calorie restriction (CR) increases longevity in many species by unknown mechanisms. The circadian clock was proposed as a potential mediator of CR. Deficiency of the core component of the circadian clock-transcriptional factor BMAL1 (brain and muscle ARNT [aryl hydrocarbon receptor nuclear translocator]-like protein 1)-results in accelerated aging. Here we investigated the role of BMAL1 in mechanisms of CR. The 30% CR diet increased the life span of wild-type (WT) mice by 20% compared to mice on anad libitum(AL) diet but failed to increase life span ofBmal1(-/-)mice. BMAL1 deficiency impaired CR-mediated changes in the plasma levels of IGF-1 and insulin. We detected a statistically significantly reduction of IGF-1 in CRvs.AL by 50 to 70% in WT mice at several daily time points tested, while inBmal1(-/-)the reduction was not significant. Insulin levels in WT were reduced by 5 to 9%, whileBmal1(-/-)induced it by 10 to 35% at all time points tested. CR up-regulated the daily average expression ofBmal1(by 150%) and its downstream target genesPeriods(by 470% forPer1and by 130% forPer2). We propose that BMAL1 is an important mediator of CR, and activation of BMAL1 might link CR mechanisms with biologic clocks.-Patel, S. A., Chaudhari, A., Gupta, R., Velingkaar, N., Kondratov, R. V. Circadian clocks govern calorie restriction-mediated life span extension through BMAL1- and IGF-1-dependent mechanisms. © FASEB.

Ovariectomy shortens the life span of female mice

PubMed Central

Benedusi, Valeria; Martini, Elisa; Kallikourdis, Marinos; Villa, Alessandro; Meda, Clara; Maggi, Adriana

2015-01-01

This study shows that lack of ovarian activity has a negative impact on the life span of female mice. The extent to which this phenomenon could be associated with the anti-inflammatory effect of estrogens was analyzed in metabolic organs and aorta, by quantitative analysis of mRNAs encoding proteins in the inflammatory cascade. We demonstrate that the TNFα, IL-1β, MCP-1, MIP-2 and IL-6 mRNA contents are increased in the liver, adipose tissue and aorta 7 months after ovariectomy (ovx) and this increased basal inflammation is maintained as the mice aged. In contrast, the extent of inflammatory gene expression is directly proportional to age in sham-operated mice. As a consequence, at 22 months, most of the inflammatory parameters examined were higher in the sham-operated group compared with the ovx group. These observations led us to propose that the decreased longevity of ovx mice may be due to an acceleration of the basal state of inflammation in metabolic organs, which is likely driven by the combination of a lack of estrogen-mediated anti-inflammatory activity and the loss of gonadal control of energy metabolism. PMID:25719423

[Effect of pineal peptide on parameters of the biological age and life span in mice].

PubMed

Anisimov, V N; Khavinson, V Kh; Zavarzina, N Iu; Zabezhinskiĭ, M A; Zimina, O A; Popovich, I G; Shtylik, A V; Arutiunian, A V; Oparina, T I; Prokopenko, V M

2001-01-01

Female CBA mice were injected with s.c. synthetic tetrapeptide Epithalon from a 6-month age until death. The drug failed to affect the body weight or food consumption, physical activity or behavioural parameters. However, it slowed down the age-related switching off of the estrus function, decreased body temperature, decelerated free redical processes, prolonged the mice life span with an accompanying drop in spontaneous tumour incidence.

Impact of Reproductive History and Exogenous Hormone Use on Cognitive Function in Midlife and Late Life

PubMed Central

Karim, Roksana; Dang, Ha; Henderson, Victor W.; Hodis, Howard N.; St John, Jan; Brinton, Roberta D.; Mack, Wendy J.

2016-01-01

Background/objectives Given the potent role of sex hormones on brain chemistry and function, we investigated the association of reproductive history indicators of hormonal exposures, including reproductive period, pregnancy, and use of hormonal contraceptives, on mid- and late-life cognition in postmenopausal women. Design Analysis of baseline data from two randomized clinical trials, the Women’s Isoflavone Soy Health (WISH) and the Early vs Late Intervention Trial of Estradiol (ELITE). Setting University academic research center Participants 830 naturally menopausal women Measurements Participants were uniformly evaluated with a cognitive battery and a structured reproductive history. Outcomes were composite scores for verbal episodic memory, executive functions, and global cognition. Reproductive variables included ages at pregnancies, menarche, and menopause, reproductive period, number of pregnancies, and use of hormones for contraception and menopausal symptoms. Multivariable linear regression evaluated associations between cognitive scores (dependent variable) and reproductive factors (independent variables), adjusting for age, race/ethnicity, income and education. Results On multivariable modeling, age at menarche ≥ 13 years of age was inversely associated with global cognition (p= 0.05). Last pregnancy after age 35 was positively associated with verbal memory (p=0.03). Use of hormonal contraceptives was positively associated with global cognition (p trend=0.04), and verbal memory (p trend=0.007). The association between hormonal contraceptive use and verbal memory and executive functions was strongest for more than 10 years of use. Reproductive period was positively associated with global cognition (p=0.04) and executive functions (p=0.04). Conclusion In this sample of healthy postmenopausal women, reproductive life events related to sex hormones, including earlier age at menarche, later age at last pregnancy, length of reproductive period, and use of

Self-Esteem Development across the Life Span: A Longitudinal Study with a Large Sample from Germany

ERIC Educational Resources Information Center

Orth, Ulrich; Maes, Jürgen; Schmitt, Manfred

2015-01-01

The authors examined the development of self-esteem across the life span. Data came from a German longitudinal study with 3 assessments across 4 years of a sample of 2,509 individuals ages 14 to 89 years. The self-esteem measure used showed strong measurement invariance across assessments and birth cohorts. Latent growth curve analyses indicated…

Use of a modified reproductive life plan to improve awareness of preconception health in women with chronic disease.

PubMed

Mittal, Pooja; Dandekar, Aparna; Hessler, Danielle

2014-01-01

Chronic diseases such as hypertension, diabetes, and obesity pose unique reproductive challenges for women. Preconception health results in improved reproductive outcomes. We designed an interventional study testing the use of a reproductive life plan to improve knowledge of preconception and contraception health in women with chronic diseases. Primarily underserved, English-and Spanish-speaking women aged 18 to 40 years with active diabetes, hypertension, or obesity were recruited. We developed a revised reproductive life plan specific to these diseases. Two resident physicians performed reproductive plan counseling. Pre- and postcounseling surveys were administered to evaluate knowledge and attitudes about chronic disease and the effects on a potential pregnancy. Twenty-seven women (average age = 31 years) were surveyed. Of the subjects, 85.2% were obese, 29.6% had hypertension, and 7.4% had diabetes. Significant increases were reported in understanding risks of pregnancy associated with diabetes (p < 0.001), hypertension (p < 0.001), and obesity (p < 0.01). After counseling, women increased their knowledge about a reproductive plan (p < 0.001) and increased support and information to make reproductive health choices (p = 0.001 and p < 0.01, respectively). The largest improvements in postcounseling variables occurred in women with the lowest precounseling test scores and in women without children. A reproductive life plan is a brief, cost-effective preconception and contraception counseling tool in the primary care setting for women with chronic diseases. This tool increases knowledge about reproductive health and enables women with chronic diseases to make informed decisions about their reproductive future.

Differential longitudinal changes in cortical thickness, surface area and volume across the adult life span: regions of accelerating and decelerating change.

PubMed

Storsve, Andreas B; Fjell, Anders M; Tamnes, Christian K; Westlye, Lars T; Overbye, Knut; Aasland, Hilde W; Walhovd, Kristine B

2014-06-18

Human cortical thickness and surface area are genetically independent, emerge through different neurobiological events during development, and are sensitive to different clinical conditions. However, the relationship between changes in the two over time is unknown. Additionally, longitudinal studies have almost invariably been restricted to older adults, precluding the delineation of adult life span trajectories of change in cortical structure. In this longitudinal study, we investigated changes in cortical thickness, surface area, and volume after an average interval of 3.6 years in 207 well screened healthy adults aged 23-87 years. We hypothesized that the relationships among metrics are dynamic across the life span, that the primary contributor to cortical volume reductions in aging is cortical thinning, and that magnitude of change varies with age and region. Changes over time were seen in cortical area (mean annual percentage change [APC], -0.19), thickness (APC, -0.35), and volume (APC, -0.51) in most regions. Volume changes were primarily explained by changes in thickness rather than area. A negative relationship between change in thickness and surface area was found across several regions, where more thinning was associated with less decrease in area, and vice versa. Accelerating changes with increasing age was seen in temporal and occipital cortices. In contrast, decelerating changes were seen in prefrontal and anterior cingulate cortices. In conclusion, a dynamic relationship between cortical thickness and surface area changes exists throughout the adult life span. The mixture of accelerating and decelerating changes further demonstrates the importance of studying these metrics across the entire adult life span. Copyright © 2014 the authors 0270-6474/14/348488-11$15.00/0.

Childhood Self-Control and Unemployment Throughout the Life Span

PubMed Central

Delaney, Liam; Egan, Mark; Baumeister, Roy F.

2015-01-01

The capacity for self-control may underlie successful labor-force entry and job retention, particularly in times of economic uncertainty. Analyzing unemployment data from two nationally representative British cohorts (N = 16,780), we found that low self-control in childhood was associated with the emergence and persistence of unemployment across four decades. On average, a 1-SD increase in self-control was associated with a reduction in the probability of unemployment of 1.4 percentage points after adjustment for intelligence, social class, and gender. From labor-market entry to middle age, individuals with low self-control experienced 1.6 times as many months of unemployment as those with high self-control. Analysis of monthly unemployment data before and during the 1980s recession showed that individuals with low self-control experienced the greatest increases in unemployment during the recession. Our results underscore the critical role of self-control in shaping life-span trajectories of occupational success and in affecting how macroeconomic conditions affect unemployment levels in the population. PMID:25870404

Immortalization of Human Fetal Cells: The Life Span of Umbilical Cord Blood-derived Cells Can Be Prolonged without Manipulating p16INK4a/RB Braking PathwayD⃞

PubMed Central

Terai, Masanori; Uyama, Taro; Sugiki, Tadashi; Li, Xiao-Kang; Umezawa, Akihiro; Kiyono, Tohru

2005-01-01

Human umbilical cord blood-derived mesenchymal stem cells (UCBMSCs) are expected to serve as an excellent alternative to bone marrow-derived human mesenchymal stem cells. However, it is difficult to study them because of their limited life span. To overcome this problem, we attempted to produce a strain of UCBMSCs with a long life span and to investigate whether the strain could maintain phenotypes in vitro. UCBMSCs were infected with retrovirus carrying the human telomerase reverse transcriptase (hTERT) to prolong their life span. The UCBMSCs underwent 30 population doublings (PDs) and stopped dividing at PD 37. The UCBMSCs newly established with hTERT (UCBTERTs) proliferated for >120 PDs. The p16INK4a/RB braking pathway leading to senescence can be inhibited by introduction of Bmi-1, a polycomb-group gene, and human papillomavirus type 16 E7, but the extension of the life span of the UCBMSCs with hTERT did not require inhibition of the p16INK4a/RB pathway. The characteristics of the UCBTERTs remained unchanged during the prolongation of life span. UCBTERTs provide a powerful model for further study of cellular senescence and for future application to cell-based therapy by using umbilical cord blood cells. PMID:15647378

Dietary consumption of monosodium L-glutamate induces adaptive response and reduction in the life span of Drosophila melanogaster.

PubMed

Abolaji, Amos O; Olaiya, Charles O; Oluwadahunsi, Oluwagbenga J; Farombi, Ebenezer O

2017-04-01

Adaptive response is the ability of an organism to better counterattack stress-induced damage in response to a number of different cytotoxic agents. Monosodium L-glutamate (MSG), the sodium salt of amino acid glutamate, is commonly used as a food additive. We investigated the effects of MSG on the life span and antioxidant response in Drosophila melanogaster (D. melanogaster). Both genders (1 to 3 days old) of flies were fed with diet containing MSG (0.1, 0.5, and 2.5-g/kg diet) for 5 days to assess selected antioxidant and oxidative stress markers, while flies for longevity were fed for lifetime. Thereafter, the longevity assay, hydrogen peroxide (H 2 O 2 ), and reactive oxygen and nitrogen species levels were determined. Also, catalase, glutathione S-transferase and acetylcholinesterase activities, and total thiol content were evaluated in the flies. We found that MSG reduced the life span of the flies by up to 23% after continuous exposure. Also, MSG increased reactive oxygen and nitrogen species and H 2 O 2 generations and total thiol content as well as the activities of catalase and glutathione S-transferase in D. melanogaster (P < .05). In conclusion, consumption of MSG for 5 days by D. melanogaster induced adaptive response, but long-term exposure reduced life span of flies. This study may therefore have public health significance in humans, and thus, moderate consumption of MSG is advocated by the authors. Copyright © 2017 John Wiley & Sons, Ltd.

CTT1 overexpression increases life span of calorie-restricted Saccharomyces cerevisiae deficient in Sod1.

PubMed

Rona, Germana; Herdeiro, Ricardo; Mathias, Cristiane Juliano; Torres, Fernando Araripe; Pereira, Marcos Dias; Eleutherio, Elis

2015-06-01

Studies using different organisms revealed that reducing calorie intake, without malnutrition, known as calorie restriction (CR), increases life span, but its mechanism is still unkown. Using the yeast Saccharomyces cerevisiae as eukaryotic model, we observed that Cu, Zn-superoxide dismutase (Sod1p) is required to increase longevity, as well as to confer protection against lipid and protein oxidation under CR. Old cells of sod1 strain also presented a premature induction of apoptosis. However, when CTT1 (which codes for cytosolic catalase) was overexpressed, sod1 and WT strains showed similar survival rates. Furthermore, CTT1 overexpression decreased lipid peroxidation and delayed the induction of apoptotic process. Superoxide is rapidly converted to hydrogen peroxide by superoxide dismutase, but it also undergoes spontaneous dismutation albeit at a slower rate. However, the quantity of peroxide produced from superoxide in this way is two-fold higher. Peroxide degradation, catalyzed by catalase, is of vital importance, because in the presence of a reducer transition metal peroxide is reduced to the highly reactive hydroxyl radical, which reacts indiscriminately with most cellular constituents. These findings might explain why overexpression of catalase was able to overcome the deficiency of Sod1p, increasing life span in response to CR.

Sleep Apnea, Reproductive Hormones and Quality of Sexual Life in Severely Obese Men

PubMed Central

Hammoud, Ahmad O.; Walker, James M.; Gibson, Mark; Cloward, Tom V.; Hunt, Steven C.; Kolotkin, Ronette L.; Adams, Ted D.; Meikle, A. Wayne

2013-01-01

The effect of sleep apnea on the reproductive function of obese men is not entirely elucidated. The objective of this study was to define the effect of sleep apnea on the reproductive hormones and sexual function in obese men. This study included 89 severely obese men with BMI ≥35 kg/m2 considering gastric bypass surgery. Anthropometrics (weight, and BMI), reproductive hormones, and sleep studies were measured. The sexual quality of life was assessed using the Impact of Weight on Quality of Life-Lite questionnaire (IWQOL-Lite). The mean age of our patients was 46.9 ± 11.0 years, the mean BMI was 47.8 ± 8.7 kg/m2 and the mean weight was 337.7 ± 62.4 lb. After correction for age and BMI, means of free testosterone per severity group of sleep apnea were as follows: no or mild sleep apnea 74.4 ± 3.8 pg/ml, moderate sleep apnea 68.6 ± 4.2 pg/ml, and severe sleep apnea 60.2 ± 2.92 pg/ml, P = 0.014. All other parameters of sleep apnea including hypopnea index, percent time below a SpO2 of 90%, and percent time below a SpO2 of 80% were also negatively correlated with testosterone levels after correction for age and BMI. BMI and presence of coronary artery disease decreased the sexual quality of life. Sleep apnea was associated with reduced sexual quality of life. In summary, sleep apnea negatively affects testosterone levels independent of BMI. Severely obese men had decreased sexual quality of life. PMID:21273994

The Life Span Model of Suicide and Its Neurobiological Foundation

PubMed Central

Ludwig, Birgit; Roy, Bhaskar; Wang, Qingzhong; Birur, Badari; Dwivedi, Yogesh

2017-01-01

The very incomprehensibility of the suicidal act has been occupying the minds of researchers and health professionals for a long time. Several theories of suicide have been proposed since the beginning of the past century, and a myriad of neurobiological studies have been conducted over the past two decades in order to elucidate its pathophysiology. Both neurobiology and psychological theories tend to work in parallel lines that need behavioral and empirical data respectively, to confirm their hypotheses. In this review, we are proposing a “Life Span Model of Suicide” with an attempt to integrate the “Stress-Diathesis Model” and the “Interpersonal Model of Suicide” into a neurobiological narrative and support it by providing a thorough compilation of related genetic, epigenetic, and gene expression findings. This proposed model comprises three layers, forming the capability of suicide: genetic factors as the predisposing Diathesis on one side and Stress, characterized by epigenetic marks on the other side, and in between gene expression and gene function which are thought to be influenced by Diathesis and Stress components. The empirical evidence of this model is yet to be confirmed and further research, specifically epigenetic studies in particular, are needed to support the presence of a life-long, evolving capability of suicide and identify its neurobiological correlates. PMID:28261051

daf-16: An HNF-3/forkhead family member that can function to double the life-span of Caenorhabditis elegans.

PubMed

Lin, K; Dorman, J B; Rodan, A; Kenyon, C

1997-11-14

The wild-type Caenorhabditis elegans nematode ages rapidly, undergoing development, senescence, and death in less than 3 weeks. In contrast, mutants with reduced activity of the gene daf-2, a homolog of the insulin and insulin-like growth factor receptors, age more slowly than normal and live more than twice as long. These mutants are active and fully fertile and have normal metabolic rates. The life-span extension caused by daf-2 mutations requires the activity of the gene daf-16. daf-16 appears to play a unique role in life-span regulation and encodes a member of the hepatocyte nuclear factor 3 (HNF-3)/forkhead family of transcriptional regulators. In humans, insulin down-regulates the expression of certain genes by antagonizing the activity of HNF-3, raising the possibility that aspects of this regulatory system have been conserved.

Lung glutathione reductase induction in aging catalase-depleted frogs correlates with early survival throughout the life span.

PubMed

Perez-Campo, R; Lopez-Torres, M; Rojas, C; Cadenas, S; Barja de Quiroga, G

1993-02-01

A comprehensive experimental study on free radical-related parameters was performed in the lung throughout the life span of 220 initially young or old frogs. No age related differences were found transversely or longitudinally for lung superoxide dismutase, catalase, Se-dependent and -independent glutathione peroxidases, glutathione reductase, GSH, GSSG, or GSSG/GSH ratio. Continuous catalase depletion with aminotriazole led to glutathione reductase induction in the lung after 14.5 months of experimentation. This was accompanied by a great increase in survival rate of treated animals in relation to controls (especially in the old group). After 26.5 months of experimentation, glutathione reductase induction was lost and GSSG/GSH values tended to increase. This was followed by a 3-month long period of acute decrease in survival rate of treated animals. It is suggested that a high antioxidant/prooxidant balance is of protective value against causes of early death and can possibly be used in the future (when appropriately controlled) to increase the number of healthy years of the normal life span.

DNA damage leads to progressive replicative decline but extends the life span of long-lived mutant animals.

PubMed

Lans, H; Lindvall, J M; Thijssen, K; Karambelas, A E; Cupac, D; Fensgård, O; Jansen, G; Hoeijmakers, J H J; Nilsen, H; Vermeulen, W

2013-12-01

Human-nucleotide-excision repair (NER) deficiency leads to different developmental and segmental progeroid symptoms of which the pathogenesis is only partially understood. To understand the biological impact of accumulating spontaneous DNA damage, we studied the phenotypic consequences of DNA-repair deficiency in Caenorhabditis elegans. We find that DNA damage accumulation does not decrease the adult life span of post-mitotic tissue. Surprisingly, loss of functional ERCC-1/XPF even further extends the life span of long-lived daf-2 mutants, likely through an adaptive activation of stress signaling. Contrariwise, NER deficiency leads to a striking transgenerational decline in replicative capacity and viability of proliferating cells. DNA damage accumulation induces severe, stochastic impairment of development and growth, which is most pronounced in NER mutants that are also impaired in their response to ionizing radiation and inter-strand crosslinks. These results suggest that multiple DNA-repair pathways can protect against replicative decline and indicate that there might be a direct link between the severity of symptoms and the level of DNA-repair deficiency in patients.

[Special mechanisms for reducing life span of cells and organisms, initiated by some weak external signals].

PubMed

Bychkovskaia, I B; Fedortseva, R F

2014-01-01

The study presents the results of many-years research conducted using biological objects of different organization level. It demonstrates special species-nonspecific form of weak external signals negative effect to cells life expectancy reduction caused by program damage of cells populations. This effect is detected after weak radiation, radio-chemical and thermal influences. It leads to faster extinction of postmitotic populations which can be a reason for life expectancy reduction of multicellular organisms. A possibility of such effect inheritance in the asexual and sexual reproduction is shown. Epigenetic mechanisms of this phenomenon are assumed.

Everyday problem solving across the adult life span: solution diversity and efficacy.

PubMed

Mienaltowski, Andrew

2011-10-01

Everyday problem solving involves examining the solutions that individuals generate when faced with problems that take place in their everyday experiences. Problems can range from medication adherence and meal preparation to disagreeing with a physician over a recommended medical procedure or compromising with extended family members over where to host Thanksgiving dinner. Across the life span, research has demonstrated divergent patterns of change in performance based on the type of everyday problems used as well as based on the way that problem-solving efficacy is operationally defined. Advancing age is associated with worsening performance when tasks involve single-solution or fluency-based definitions of effectiveness. However, when efficacy is defined in terms of the diversity of strategies used, as well as by the social and emotional impact of solution choice on the individual, performance is remarkably stable and sometimes even improves in the latter half of life. This article discusses how both of these approaches to everyday problem solving inform research on the influence that aging has on everyday functioning. © 2011 New York Academy of Sciences.

Aging Theories for Establishing Safe Life Spans of Airborne Critical Structural Components

NASA Technical Reports Server (NTRS)

Ko, William L.

2003-01-01

New aging theories have been developed to establish the safe life span of airborne critical structural components such as B-52B aircraft pylon hooks for carrying air-launch drop-test vehicles. The new aging theories use the equivalent-constant-amplitude loading spectrum to represent the actual random loading spectrum with the same damaging effect. The crack growth due to random loading cycling of the first flight is calculated using the half-cycle theory, and then extrapolated to all the crack growths of the subsequent flights. The predictions of the new aging theories (finite difference aging theory and closed-form aging theory) are compared with the classical flight-test life theory and the previously developed Ko first- and Ko second-order aging theories. The new aging theories predict the number of safe flights as considerably lower than that predicted by the classical aging theory, and slightly lower than those predicted by the Ko first- and Ko second-order aging theories due to the inclusion of all the higher order terms.

Everyday problem solving across the adult life span: solution diversity and efficacy

PubMed Central

Mienaltowski, Andrew

2013-01-01

Everyday problem solving involves examining the solutions that individuals generate when faced with problems that take place in their everyday experiences. Problems can range from medication adherence and meal preparation to disagreeing with a physician over a recommended medical procedure or compromising with extended family members over where to host Thanksgiving dinner. Across the life span, research has demonstrated divergent patterns of change in performance based on the type of everyday problems used as well as based on the way that problem-solving efficacy is operationally defined. Advancing age is associated with worsening performance when tasks involve single-solution or fluency-based definitions of effectiveness. However, when efficacy is defined in terms of the diversity of strategies used, as well as by the social and emotional impact of solution choice on the individual, performance is remarkably stable and sometimes even improves in the latter half of life. This article discusses how both of these approaches to everyday problem solving inform research on the influence that aging has on everyday functioning. PMID:22023569

Dietary resveratrol prevents Alzheimer's markers and increases life span in SAMP8.

PubMed

Porquet, David; Casadesús, Gemma; Bayod, Sergi; Vicente, Alberto; Canudas, Anna M; Vilaplana, Jordi; Pelegrí, Carme; Sanfeliu, Coral; Camins, Antoni; Pallàs, Mercè; del Valle, Jaume

2013-10-01

Resveratrol is a polyphenol that is mainly found in grapes and red wine and has been reported to be a caloric restriction (CR) mimetic driven by Sirtuin 1 (SIRT1) activation. Resveratrol increases metabolic rate, insulin sensitivity, mitochondrial biogenesis and physical endurance, and reduces fat accumulation in mice. In addition, resveratrol may be a powerful agent to prevent age-associated neurodegeneration and to improve cognitive deficits in Alzheimer's disease (AD). Moreover, different findings support the view that longevity in mice could be promoted by CR. In this study, we examined the role of dietary resveratrol in SAMP8 mice, a model of age-related AD. We found that resveratrol supplements increased mean life expectancy and maximal life span in SAMP8 and in their control, the related strain SAMR1. In addition, we examined the resveratrol-mediated neuroprotective effects on several specific hallmarks of AD. We found that long-term dietary resveratrol activates AMPK pathways and pro-survival routes such as SIRT1 in vivo. It also reduces cognitive impairment and has a neuroprotective role, decreasing the amyloid burden and reducing tau hyperphosphorylation.

Hypothalamic neural systems controlling the female reproductive life cycle: Gonadotropin-releasing hormone, glutamate, and GABA

PubMed Central

Maffucci, Jacqueline A.; Gore, Andrea C.

2009-01-01

The hypothalamic-pituitary-gonadal (HPG) axis undergoes a number of changes throughout the reproductive life cycle that are responsible for the development, puberty, adulthood, and senescence of reproductive systems. This natural progression is dictated by the neural network controlling the hypothalamus including the cells that synthesize and release gonadotropin-releasing hormone (GnRH) and their regulatory neurotransmitters. Glutamate and GABA are the primary excitatory and inhibitory neurotransmitters in the central nervous system, and as such contribute a great deal to modulating this axis throughout the lifetime via their actions on receptors in the hypothalamus, both directly on GnRH neurons as well as indirectly though other hypothalamic neural networks. Interactions among GnRH neurons, glutamate, and GABA, including the regulation of GnRH gene and protein expression, hormone release, and modulation by estrogen, are critical to age-appropriate changes in reproductive function. Here, we present evidence for the modulation of GnRH neurosecretory cells by the balance of glutamate and GABA in the hypothalamus, and the functional consequences of these interactions on reproductive physiology across the life cycle. PMID:19349036

The specificity of childhood adversities and negative life events across the life span to anxiety and depressive disorders.

PubMed

Spinhoven, Philip; Elzinga, Bernet M; Hovens, Jacqueline G F M; Roelofs, Karin; Zitman, Frans G; van Oppen, Patricia; Penninx, Brenda W J H

2010-10-01

Although several studies have shown that life adversities play an important role in the etiology and maintenance of both depressive and anxiety disorders, little is known about the relative specificity of several types of life adversities to different forms of depressive and anxiety disorder and the concurrent role of neuroticism. Few studies have investigated whether clustering of life adversities or comorbidity of psychiatric disorders critically influence these relationships. Using data from the Netherlands Study of Depression and Anxiety (NESDA), we analyzed the association of childhood adversities and negative life experiences across the lifespan with lifetime DSM-IV-based diagnoses of depression or anxiety among 2288 participants with at least one affective disorder. Controlling for comorbidity and clustering of adversities the association of childhood adversity with affective disorders was greater than that of negative life events across the life span with affective disorders. Among childhood adversities, emotional neglect was specifically associated with depressive disorder, dysthymia, and social phobia. Persons with a history of emotional neglect and sexual abuse were more likely to develop more than one lifetime affective disorder. Neuroticism and current affective disorder did not affect the adversity-disorder relationships found. Using a retrospective study design, causal interpretations of the relationships found are not warranted. Emotional neglect seems to be differentially related to depression, dysthymia and social phobia. This knowledge may help to reduce underestimation of the impact of emotional abuse and lead to better recognition and treatment to prevent long-term disorders. Copyright 2010 Elsevier B.V. All rights reserved.

Reproductive effects on skeletal health in Shuar women of Amazonian Ecuador: a life history perspective.

PubMed

Madimenos, Felicia C; Snodgrass, J Josh; Liebert, Melissa A; Cepon, Tara J; Sugiyama, Lawrence S

2012-01-01

Clinical and epidemiological research suggest that bone mineral density (BMD) in women is shaped by various reproductive factors such as parity and lactation patterns. However, the extent of these effects on BMD remains unclear because of contradictory findings and a focus on industrialized populations. Because fertility patterns in these groups are vastly different than those of women from non-Western, subsistence populations, our current understanding of the reproductive effects on skeletal health is incomplete. Using a life history perspective, this study examines the relationship between reproductive factors and bone density among women from the Indigenous Shuar population, an Amazonian Ecuadorian forager-horticulturalist group. This preliminary, cross-sectional study included 130 premenopausal and postmenopausal women (14-86 years old) from the Morona-Santiago region of Ecuador. Anthropometrics were recorded, as was estimated BMD using a calcaneal ultrasonometer. A reproductive history questionnaire was administered that included questions regarding menarche, parity, lactation patterns, and menopause. Among postmenopausal women, early menarche and greater stature were significantly associated with higher bone density values. Among premenopausal women, few significant relationships between bone values and reproductive variables were documented; effects of lactation appeared to be transient and restored following weaning. Although preliminary and not based on longitudinal data, these findings suggest that the effects of reproduction are transient as the system of calcium homeostasis in premenopausal women efficiently restores the bone loss that results from metabolically active reproductive states. Further, this research suggests that the timing of early life history events may canalize bone density phenotype. Copyright © 2012 Wiley Periodicals, Inc.

The reproductive biology and early life ecology of a common Caribbean brain coral, Diploria labyrinthiformis (Scleractinia: Faviinae)

NASA Astrophysics Data System (ADS)

Chamberland, Valérie F.; Snowden, Skylar; Marhaver, Kristen L.; Petersen, Dirk; Vermeij, Mark J. A.

2017-03-01

Despite the fact that most of the severe demographic bottlenecks in coral populations occur during their earliest life stages, information on the reproductive biology and early life history traits of many coral species is limited and often inferred from adult traits only. This study reports on several atypical aspects of the reproductive biology and early life ecology of the grooved brain coral, Diploria labyrinthiformis (Linnaeus, 1758), a conspicuous reef-building species on Caribbean reefs. The timing of gamete release of D. labyrinthiformis was monitored in Curaçao over eight consecutive months, and embryogenesis, planulae behavior, and settlement rates were observed and quantified. We further studied growth and symbiont acquisition in juvenile D. labyrinthiformis for 3.5 yr and compared settler survival under ambient and nutrient-enriched conditions in situ. Notably, D. labyrinthiformis reproduced during daylight hours in six consecutive monthly spawning events between May and September 2013, with a peak in June. This is the largest number of reproductive events per year ever observed in a broadcast-spawning Caribbean coral species. In settlement experiments, D. labyrinthiformis planulae swam to the bottom of culture containers 13 h after spawning and rapidly settled when provided with settlement cues (42% within 14 h). After 5 months, the survival and growth rates of settled juveniles were 3.7 and 1.9 times higher, respectively, for settlers that acquired zooxanthellae within 1 month after settlement, compared to those that acquired symbionts later on. Nutrient enrichment increased settler survival fourfold, but only for settlers that had acquired symbionts within 1 month after settlement. With at least six reproductive events per year, a short planktonic larval phase, high settlement rates, and a positive response to nutrient enrichment, the broadcast-spawning species D. labyrinthiformis displays a range of reproductive and early life-history traits that

Sublethal effects of buprofezin on development and reproduction in the white-backed planthopper, Sogatella furcifera (Hemiptera: Delphacidae).

PubMed

Ali, Ehsan; Liao, Xun; Yang, Peng; Mao, Kaikai; Zhang, Xiaolei; Shakeel, Muhammad; Salim, Abdalla M A; Wan, Hu; Li, Jianhong

2017-12-05

In the present study, the effects of sublethal concentrations of buprofezin on life-table traits of S. furcifera were evaluated for two consecutive generations (F0 and F1). Our results exhibited that the fecundity, life span (longevity) and hatchability of the F0 and F1 generations were significantly decreased at LC 30 compared to the control. However, copulation was not significantly affected for the F0 or F1 generations at sublethal concentrations. The female life span was affected negatively at both treatments in F0 and at LC 30 in F1, compared to the control. Furthermore, significant effects of the sublethal concentrations were found on the developmental rate of all instars except the 3 rd instar of F1. However, the pre-adult period, total pre-oviposition period (TPOP) and adult pre-oviposition period (APOP) significantly increased in F1 individuals at LC 30 and LC 10 compared to the control. Our findings revealed that demographic characters (survival rate, intrinsic rate of increase (ri), finite rate of increase (λ), net reproductive rate (R 0 ), and gross reproductive rate (GRR)) of the F1 generation (from F0 parents) significantly decreased compared to the untreated group; however, the generation time (T) increased at LC 10 . Therefore, the results suggested that buprofezin could adversely affect individuals in the successive generation.

Extreme environments select for reproductive assurance: evidence from evening primroses (Oenothera).

PubMed

Evans, Margaret E K; Hearn, David J; Theiss, Kathryn E; Cranston, Karen; Holsinger, Kent E; Donoghue, Michael J

2011-07-01

Competing evolutionary forces shape plant breeding systems (e.g. inbreeding depression, reproductive assurance). Which of these forces prevails in a given population or species is predicted to depend upon such factors as life history, ecological conditions, and geographical context. Here, we examined two such predictions: that self-compatibility should be associated with the annual life history or extreme climatic conditions. We analyzed data from a clade of plants remarkable for variation in breeding system, life history and climatic conditions (Oenothera, sections Anogra and Kleinia, Onagraceae). We used a phylogenetic comparative approach and Bayesian or hybrid Bayesian tests to account for phylogenetic uncertainty. Geographic information system (GIS)-based climate data and ecological niche modeling allowed us to quantify climatic conditions. Breeding system and reproductive life span are not correlated in Anogra and Kleinia. Instead, self-compatibility is associated with the extremes of temperature in the coldest part of the year and precipitation in the driest part of the year. In the 60 yr since this pattern was anticipated, this is the first demonstration of a relationship between the evolution of self-compatibility and climatic extremes. We discuss possible explanations for this pattern and possible implications with respect to anthropogenic climate change. © 2011 The Authors. New Phytologist © 2011 New Phytologist Trust.

Modeling Life-Span Growth Curves of Cognition Using Longitudinal Data with Multiple Samples and Changing Scales of Measurement

ERIC Educational Resources Information Center

McArdle, John J.; Grimm, Kevin J.; Hamagami, Fumiaki; Bowles, Ryan P.; Meredith, William

2009-01-01

The authors use multiple-sample longitudinal data from different test batteries to examine propositions about changes in constructs over the life span. The data come from 3 classic studies on intellectual abilities in which, in combination, 441 persons were repeatedly measured as many as 16 times over 70 years. They measured cognitive constructs…

The structure of late-life depressive symptoms across a 20-year span: a taxometric investigation.

PubMed

Holland, Jason M; Schutte, Kathleen K; Brennan, Penny L; Moos, Rudolf H

2010-03-01

Past studies of the underlying structure of depressive symptoms have yielded mixed results, with some studies supporting a continuous conceptualization and others supporting a categorical one. However, no study has examined this research question with an exclusively older adult sample, despite the potential uniqueness of late-life depressive symptoms. In the present study, the underlying structure of late-life depressive symptoms was examined among a sample of 1,289 individuals across 3 waves of data collection spanning 20 years. The authors employed a taxometric methodology using indicators of depression derived from the Research Diagnostic Criteria (R. L. Spitzer, J. Endicott, & E. Robins, 1978). Maximum eigenvalue analyses and inchworm consistency tests generally supported a categorical conceptualization and identified a group that was primarily characterized by thoughts about death and suicide. However, compared to a categorical depression variable, depressive symptoms treated continuously were generally better predictors of relevant criterion variables. These findings suggest that thoughts of death and suicide may characterize a specific type of late-life depression, yet a continuous conceptualization still typically maximizes the predictive utility of late-life depressive symptoms.

Minocycline, but not ascorbic acid, increases motor activity and extends the life span of Drosophila melanogaster.

PubMed

Mora, Marylhi; Medina-Leendertz, Shirley J; Bonilla, Ernesto; Terán, Raikelin E; Paz, Milagros C; Arcaya, José Luis

2013-06-01

In the present study we compared the effects of minocycline and ascorbic acid in the life span, motor activity and lipid peroxidation of Drosophila melanogaster, in an effort to find a substance capable of providing protection against oxidative stress in aging. In the flies treated with minocycline a very significant increase in the life span (101 +/- 1.33 days) was observed when compared to those treated with ascorbic acid and controls (42.3% and 38.4%, respectively). The motor activity of minocycline treated flies also increased significantly with respect to control and ascorbic acid fed flies, from the 3rd to the 9th week of treatment. With regard to lipid peroxidation, it was found that the levels of malondialdehyde (MDA) in flies treated with minocycline showed no statistical differences to the control on the first day of treatment, but a significantly lower content on the day of 50% survival. In contrast, in flies treated with ascorbic acid significantly elevated levels of MDA compared to control and minocycline treated flies were detected throughout. These results suggest a protective effect of minocycline against oxidative stress and aging in D. melanogaster. An inhibitory effect on reactive oxygen species production may be an important contributing factor.

Life span and structure of ephemeral root modules of different functional groups from a desert system.

PubMed

Liu, Bo; He, Junxia; Zeng, Fanjiang; Lei, Jiaqiang; Arndt, Stefan K

2016-07-01

The terminal branch orders of plant root systems have been proposed as short-lived 'ephemeral' modules specialized for resource absorption. The occurrence of ephemeral root modules has so far only been reported for a temperate tree species and it is unclear if the concept also applies to other woody (shrub, tree) and herb species. Fine roots of 12 perennial dicotyledonous herb, shrub and tree species were monitored for two growing seasons using a branch-order classification, sequential sampling and rhizotrons in the Taklamakan desert. Two root modules existed in all three plant functional groups. Among the first five branch orders, the first two (perennial herbs, shrubs) or three (trees) root orders were ephemeral and had a primary anatomical structure, high nitrogen (N) concentrations, high respiration rates and very short life spans of 1-4 months, whereas the last two branch orders in all functional groups were perennial, with thicker diameters, no or collapsed cortex, distinct secondary growth, low N concentrations, low respiration rates, but much longer life spans. Ephemeral, short-lived root modules and long-lived, persistent root modules seem to be a general feature across many plant functional groups and could represent a basic root system design. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Older Motherhood and the Changing Life Course in the Era of Assisted Reproductive Technologies.

PubMed

Friese, Carrie; Becker, Gay; Nachtigall, Robert D

2008-01-01

Midlife, once a focus of particular interest to gerontologists because of its implications for later life, has recently received little attention. But as new reproductive technologies have expanded in the United States, motherhood is occurring at older ages. While older motherhood is not a new social practice, what is unique is that an increasing number of women are becoming pregnant through technological means, often for the first time, at the end of their reproductive cycle. These women can be understood as part of a new middle age, engaging in new life course possibilities that respond to changing social, cultural, physical, and economic realities, and potentially extending much later in the life course. Drawing on interviews with 79 couples, we utilize symbolic interactionist conceptualizations of identity and stigma to consider how women negotiate the shifting social identities associated with older motherhood. We conclude that older motherhood will be one phenomenon contributing to an enduring change in views of what constitutes old age, and that it will be seen as occurring much later in the life course.

Older Motherhood and the Changing Life Course in the Era of Assisted Reproductive Technologies

PubMed Central

Friese, Carrie; Becker, Gay; Nachtigall, Robert D.

2008-01-01

Midlife, once a focus of particular interest to gerontologists because of its implications for later life, has recently received little attention. But as new reproductive technologies have expanded in the United States, motherhood is occurring at older ages. While older motherhood is not a new social practice, what is unique is that an increasing number of women are becoming pregnant through technological means, often for the first time, at the end of their reproductive cycle. These women can be understood as part of a new middle age, engaging in new life course possibilities that respond to changing social, cultural, physical, and economic realities, and potentially extending much later in the life course. Drawing on interviews with 79 couples, we utilize symbolic interactionist conceptualizations of identity and stigma to consider how women negotiate the shifting social identities associated with older motherhood. We conclude that older motherhood will be one phenomenon contributing to an enduring change in views of what constitutes old age, and that it will be seen as occurring much later in the life course. PMID:18443646

The control processes and subjective well-being of Chinese teachers: evidence of convergence with and divergence from the key propositions of the motivational theory of life-span development

PubMed Central

Wong, Wan-chi; Li, Yin; Sun, Xiaoyan; Xu, Huanu

2014-01-01

An analytical review of the motivational theory of life-span development reveals that this theory has undergone a series of elegant theoretical integrations. Its claim to universality nonetheless brings forth unresolved controversies. With the purpose of scrutinizing the key propositions of this theory, an empirical study was designed to examine the control processes and subjective well-being of Chinese teachers (N = 637). The OPS-Scales (Optimization in Primary and Secondary Control Scales) for the Domain of Teaching were constructed to assess patterns of control processes. Three facets of subjective well-being were investigated with the Positive and Negative Affect Schedule, the Life Satisfaction Scale, and the Subjective Vitality Scale. The results revealed certain aspects of alignment with and certain divergences from the key propositions of the motivational theory of life-span development. Neither “primacy of primary control” nor “primacy of secondary control” was clearly supported. Notably, using different criteria for subjective well-being yielded different subtypes of primary and secondary control as predictors. The hypothesized life-span trajectories of primary and secondary control received limited support. To advance the theory in this area, we recommend incorporating Lakatos' ideas about sophisticated falsification by specifying the hard core of the motivational theory of life-span development and articulating new auxiliary hypotheses. PMID:24904483

Linguistic Evidence for the Failure Mindset as a Predictor of Life Span Longevity.

PubMed

Penzel, Ian B; Persich, Michelle R; Boyd, Ryan L; Robinson, Michael D

2017-06-01

When people think that their efforts will fail to achieve positive outcomes, they sometimes give up their efforts after control, which can have negative health consequences. Problematic orientations of this type, such as pessimism, helplessness, or fatalism, seem likely to be associated with a cognitive mindset marked by higher levels of accessibility for failure words or concepts. Thus, the purpose of the present research was to determine whether there are individual differences in the frequency with which people think about failure, which in turn are likely to impact health across large spans of time. Following self-regulatory theories of health and the learned helplessness tradition, two archival studies (total n = 197) scored texts (books or speeches) for their use of failure words, a category within the Harvard IV dictionary of the General Inquirer. People who used failure words more frequently exhibited shorter subsequent life spans, and this relationship remained significant when controlling for birth year. Furthermore, study 2 implicated behavioral factors. For example, the failure/longevity relationship was numerically stronger among people whose causes of death appeared to be preventable rather than non-preventable. These results significantly extend our knowledge of the personality/longevity relationship while highlighting the value of individual differences in word usage as predictors of health and mortality.

Rights of life. Sexuality and reproduction.

PubMed

Shallat, L

1993-01-01

Despite the inclusion in international human rights statements of the right to "decide freely and responsibly" the number of children to have, women are rarely able to exercise their right to reproductive and sexual choices. Historically, discussions of human rights have ignored reproductive rights because women have been excluded from the spheres where rights have been articulated and because of male attempts to control female reproduction and sexuality. The fact that reproductive rights have found their way into international declarations reflects a desire to "make the world safe for contraception" rather than to meet women's needs. International statements usually include one phrase that crucially needs defining: the right to exercise reproductive autonomy "freely and responsibly." Can governments, for example, take steps (and if so, what steps can they take) to insure that their citizens exercise their right responsibly? Because the right has been formulated by the population movement and the women's movement, it lacks the clarity necessary to be effective in influencing policy. Most women's rights activists read "freely and responsibly" to be in opposition to the goals of population control in developing countries and are uneasy with the alliance of feminists with the population establishment. Reproductive rights issues include fecundity, fertility, and infertility; voluntary motherhood; sex education and access to contraceptive usage; recognition of sexual pleasure in its various forms as a human right; emphasizing equal male-female responsibility; and including women in policy-making. International human rights declarations are a powerful platform for the advancement and protection of reproductive rights, and various legal strategies can be used to reform domestic laws.

Minocycline increases the life span and motor activity and decreases lipid peroxidation in manganese treated Drosophila melanogaster.

PubMed

Bonilla, E; Contreras, R; Medina-Leendertz, S; Mora, M; Villalobos, V; Bravo, Y

2012-03-29

The objective of this study was to investigate the effect of Minocycline in the life span, motor activity, and lipid peroxidation of Drosophila melanogaster treated with manganese. Two days after emerging from the pupa male wild-type D. melanogaster were fed for 13 days with corn media containing 15 mM manganese. Then, they were divided in six groups of 300 flies each: group (a) remained treated with manganese (Mn group); group (b) began treatment with Minocycline (0.05 mM) (Mn-Minocycline group); group (c) received no additional treatment (Mn-no treatment group); group (d) simultaneously fed with manganese and Minocycline (Mn+Minocycline group). Additionally, a control (group e) with no treatment and another group (f) fed only with Minocycline after emerging from the pupa were added. All the manganese treated flies (group a) were dead on the 25th day. The life span in group f (101.66±1.33 days, mean S.E.M.) and of group b (97.00±3.46 days) were similar, but in both cases it was significantly higher than in group e (68.33±1.76 days), group c (67.05±2.30 days) and in those of group d (37.33±0.88). Manganese (groups a and d) decreased motor activity in D. melanogaster. In the Minocycline fed flies (groups b and f) a higher motor activity was detected. In Mn-Minocycline and Mn+Minocycline treated flies a significant decrease of MDA levels was detected when compared to the Minocycline group indicating that Minocycline and Mn appear to have a synergistic effect. In conclusion, Minocycline increased the life span and motor activity and decreased MDA formation of manganese treated D. melanogaster, probably by an inhibition of the production of reactive oxygen species. Manganese also exerted an antioxidant effect as shown by the significant decrease of MDA levels when compared to control flies. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Racial and Ethnic Health Disparities in Reproductive Medicine: An Evidence-Based Overview

PubMed Central

Owen, Carter M.; Goldstein, Ellen H.; Clayton, Janine A.; Segars, James H.

2014-01-01

Racial and ethnic health disparities in reproductive medicine exist across the life span and are costly and burdensome to our healthcare system. Reduction and ultimate elimination of health disparities is a priority of the National Institutes of Health who requires reporting of race and ethnicity for all clinical research it supports. Given the increasing rates of admixture in our population, the definition and subsequent genetic significance of self-reported race and ethnicity used in health disparity research is not straightforward. Some groups have advocated using self-reported ancestry or carefully selected single-nucleotide polymorphisms, also known as ancestry informative markers, to sort individuals into populations. Despite the limitations in our current definitions of race and ethnicity in research, there are several clear examples of health inequalities in reproductive medicine extending from puberty and infertility to obstetric outcomes. We acknowledge that socioeconomic status, education, insurance status, and overall access to care likely contribute to the differences, but these factors do not fully explain the disparities. Epigenetics may provide the biologic link between these environmental factors and the transgenerational disparities that are observed. We propose an integrated view of health disparities across the life span and generations focusing on the metabolic aspects of fetal programming and the effects of environmental exposures. Interventions aimed at improving nutrition and minimizing adverse environmental exposures may act synergistically to reverse the effects of these epigenetic marks and improve the outcome of our future generations. PMID:23934691

Life cycle of lithobiidae - with a discussion of the r-and K-selection theory.

PubMed

Albert, Anke M

1983-02-01

The life cycle of two lithobiid species (Chilopoda: Lithobiidae) Lithobius mutabilis L. Koch and L. curtipes C.L. Koch in an old beech stand in the Solling is described. In addition to a main egg-laying period lithobiids are able to lay eggs continuously throughout the year. The reproductive potential is small, as only one egg is laid over several days. Most juveniles hatch in the spring and over-winter as L3 or L4 larvae. Epimorph development to attainment of sexual maturity takes nearly 2 years. Adult L. mutablilis live a further 2 years or more, adult L. curtipes about 1 year or more. Total life span is about 5-6 years for L. mutabilis and 4-5 years for L. curtipes. Egg development times and instar durations can be very different for different animals. Mortality is relatively high for eggs and small juveniles and low for post larval instars except the very old animals. A method is presented for construction of a survivorship curve from monthly abundance figures. Due to their slow development, late attainment of reproductive period, long reproductive phase, low reproductive potential, long life span, low mortality of post larval instars except very old animals, lithobiids can be regarded as K-strategists or, better, equilibrium species, among the arthropods. It is argued that the theory of r- and K-selection in its general use is not sufficient for a description of the ecological strategies of animals such as Lithobiomorpha. For lithobiids, variability in development time is a very important means of keeping population size at a constant level. The life cycle of the two lithobiid species is compared with ahat of Geophilomorpha and one henicopid species also occurring in the Solling.

Hour Glass Half-Full or Half-Empty? Future Time Perspective and Preoccupation with Negative Events Across the Life Span

PubMed Central

Strough, JoNell; de Bruin, Wändi Bruine; Parker, Andrew M.; Lemaster, Philip; Pichayayothin, Nipat; Delaney, Rebecca

2016-01-01

According to socioemotional selectivity theory, older adults' emotional well-being stems from having limited future time perspective that motivates them to maximize well-being in the “here and now.” Presumably, then, older adults' time horizons are associated with emotional competencies that boost positive affect and dampen negative affect, but little research has addressed this. Using a US national adult life-span sample (N= 3,933, 18-93 yrs), we found that a two-factor model of future time perspective (focus on future opportunities; focus on limited time) fit the data better than a one-factor model. Through middle age, people perceived the life-span hourglass as half full—they focused more on future opportunities than limited time. Around age 60, the balance changed to increasingly perceiving the life-span hourglass as half empty—they focused less on future opportunities and more on limited time. This pattern held even after accounting for perceived health, self-reported decision-making ability, and retirement status. At all ages, women's time horizons focused more on future opportunities compared to men's, and men's focused more on limited time. Focusing on future opportunities was associated with reporting less preoccupation with negative events, whereas focusing on limited time was associated with reporting more preoccupation. Older adults reported less preoccupation with negative events and this association was stronger after controlling for their perceptions of limited time and fewer future opportunities, suggesting that other pathways may explain older adults' reports of their ability to disengage from negative events. Insights gained and questions raised by measuring future time perspective as two dimensions are discussed. PMID:27267222

Hour glass half full or half empty? Future time perspective and preoccupation with negative events across the life span.

PubMed

Strough, JoNell; Bruine de Bruin, Wändi; Parker, Andrew M; Lemaster, Philip; Pichayayothin, Nipat; Delaney, Rebecca

2016-09-01

According to socioemotional selectivity theory, older adults' emotional well-being stems from having a limited future time perspective that motivates them to maximize well-being in the "here and now." Presumably, then, older adults' time horizons are associated with emotional competencies that boost positive affect and dampen negative affect, but little research has addressed this. Using a U.S. adult life-span sample (N = 3,933; 18-93 years), we found that a 2-factor model of future time perspective (future opportunities; limited time) fit the data better than a 1-factor model. Through middle age, people perceived the life-span hourglass as half full-they focused more on future opportunities than limited time. Around Age 60, the balance changed to increasingly perceiving the life-span hourglass as half empty-they focused less on future opportunities and more on limited time, even after accounting for perceived health, self-reported decision-making ability, and retirement status. At all ages, women's time horizons focused more on future opportunities compared with men's, and men's focused more on limited time. Focusing on future opportunities was associated with reporting less preoccupation with negative events, whereas focusing on limited time was associated with reporting more preoccupation. Older adults reported less preoccupation with negative events, and this association was stronger after controlling for their perceptions of limited time and fewer future opportunities, suggesting that other pathways may explain older adults' reports of their ability to disengage from negative events. Insights gained and questions raised by measuring future time perspective as 2 dimensions are discussed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A general benevolence dimension that links neural, psychological, economic, and life-span data on altruistic tendencies.

PubMed

Hubbard, Jason; Harbaugh, William T; Srivastava, Sanjay; Degras, David; Mayr, Ulrich

2016-10-01

[Correction Notice: An Erratum for this article was reported in Vol 145(10) of Journal of Experimental Psychology: General (see record 2016-46925-004). In the article, there was an error in the Task, Stimuli, and Procedures section. In the 1st sentence in the 6th paragraph, “Following the scanning phase, participants completed self-report questionnaires meant to reflected the Prosocial Disposition construct: the agreeableness scale from the Big F, which includes empathic concern and perspective-taking, and a scale of personality descriptive adjectives related to altruistic behavior (Wood, Nye, & Saucier, 2010).” should have read: “Following the scanning phase, participants completed self-report questionnaires that contained scales to reflect the Prosocial Disposition construct: the Big Five Inventory (BFI; John et al., 1991), from which we used the agreeableness scale to measure prosocial disposition; the Interpersonal Reactivity Index (IRI; Davis, 1980), from which we used the empathic concern and perspective-taking scales; and a scale of personality descriptive adjectives related to altruistic behavior (Wood, Nye, & Saucier, 2010).”] Individual and life span differences in charitable giving are an important economic force, yet the underlying motives are not well understood. In an adult, life span sample, we assessed manifestations of prosocial tendencies across 3 different measurement domains: (a) psychological self-report measures, (b) actual giving choices, and (c) fMRI-derived, neural indicators of “pure altruism.” The latter expressed individuals’ activity in neural valuation areas when charities received money compared to when oneself received money and thus reflected an altruistic concern for others. Results based both on structural equation modeling and unit-weighted aggregate scores revealed a strong higher-order General Benevolence dimension that accounted for variability across all measurement domains. The fact that the neural measures

Coping strategies: gender differences and development throughout life span.

PubMed

Meléndez, Juan Carlos; Mayordomo, Teresa; Sancho, Patricia; Tomás, José Manuel

2012-11-01

Development during life-span implies to cope with stressful events, and this coping may be done with several strategies. It could be useful to know if these coping strategies differ as a consequence of personal characteristics. This work uses the Coping with Stress Questionnaire with this aim using a sample of 400 participants. Specifically, the effects of gender and age group (young people, middle age and elderly), as well as its interaction on coping strategies is studied. With regard to age, on one hand, it is hypothesised a decrement in the use of coping strategies centred in problem solving and social support seeking as age increases. On the other hand, the use of emotional coping is hypothesised to increase with age. With respect to gender, it is hypothesised a larger use of emotional coping and social support seeking within women, and a larger use of problem solving within men. A MANOVA found significant effects for the two main effects (gender and age) as well as several interactions. Separate ANOVAs allowed us to test for potential differences in each of the coping strategies measured in the CAE. These results partially supported the hypotheses. Results are discussed in relation to scientific literature on coping, age and gender.

Investigating Relationships between Reproduction, Immune Defenses, and Cortisol in Dall Sheep.

PubMed

Downs, Cynthia J; Boan, Brianne V; Lohuis, Thomas D; Stewart, Kelley M

2018-01-01

Life-history theory is fundamental to understanding how animals allocate resources among survival, development, and reproduction, and among traits within these categories. Immediate trade-offs occur within a short span of time and, therefore, are more easily detected. Trade-offs, however, can also manifest across stages of the life cycle, a phenomenon known as carryover effects. We investigated trade-offs on both time scales in two populations of Dall sheep ( Ovis dalli dalli ) in Southcentral Alaska. Specifically, we (i) tested for glucocorticoid-mediated carryover effects from the breeding season on reproductive success and immune defenses during parturition and (ii) tested for trade-offs between immune defenses and reproduction within a season. We observed no relationship between cortisol during mating and pregnancy success; however, we found marginal support for a negative relationship between maternal cortisol and neonate birth weights. Low birth weights, resulting from high maternal cortisol, may result in low survival or low fecundity for the neonate later in life, which could result in overall population decline. We observed a negative relationship between pregnancy and bacterial killing ability, although we observed no relationship between pregnancy and haptoglobin. Study site affected bactericidal capacity and the inflammatory response, indicating the influence of external factors on immune responses, although we could not test hypotheses about the cause of those differences. This study helps advance our understanding of the plasticity and complexity of the immune system and provides insights into the how individual differences in physiology may mediate differences in fitness.

Introducing reproductive life plan-based information in contraceptive counselling: an RCT.

PubMed

Stern, J; Larsson, M; Kristiansson, P; Tydén, T

2013-09-01

Can reproductive life plan (RLP)-based information in contraceptive counselling before pregnancy increase women's knowledge of reproduction, and of the importance of folic acid intake in particular? The RLP-based information increased women's knowledge of reproduction including knowledge of folic acid intake. Many women have insufficient knowledge of reproduction, including a health-promoting lifestyle prior to conception, and highly educated women in particular postpone childbearing until an age when their fertile capacity has started to decrease. The study was an randomized controlled trial with one intervention group (IG) and two control groups (CG1, CG2). A sample size calculation indicated that 82 women per group would be adequate. Recruitment took place during 3 months in 2012 and 299 women were included. The women were randomized in blocks of three. All groups received standard care (contraceptive counselling, Chlamydia testing, cervical screening). In addition, women in the IG were given oral and written RLP-based information about reproduction. A total of 299 out of 338 (88%) Swedish-speaking women visiting a Student Health Centre were included (mean age 23 years); response rate was 88%. Before the counselling, women in the IG and the CG1 completed a baseline questionnaire, including questions about lifestyle changes in connection to pregnancy planning, family planning intentions and knowledge of reproduction (e.g. the fecundity of an ovum). At follow-up 2 months after inclusion, a structured telephone interview was performed in all groups (n = 262, 88% participation rate). There was no difference between the groups regarding the mean knowledge score at baseline. The IG scored higher at follow-up than at baseline (P < 0.001); the mean increased from 6.4 to 9.0 out of a maximum 20 points. The women in the CG1 scored no differently at follow-up than at baseline. The difference in the knowledge score between the IG and the two CGs was significant (P < 0

The effect of age at first calving and calving interval on productive life and lifetime profit in korean holsteins.

PubMed

Do, Changhee; Wasana, Nidarshani; Cho, Kwanghyun; Choi, Yunho; Choi, Taejeong; Park, Byungho; Lee, Donghee

2013-11-01

This study was performed to estimate the effect of age at first calving and first two calving intervals on productive life and life time profit in Korean Holsteins. Reproduction data of Korean Holsteins born from 1998 to 2004 and lactation data from 276,573 cows with birth and last dry date that calved between 2000 and 2010 were used for the analysis. Lifetime profit increased with the days of life span. Regression of Life Span on Lifetime profit indicated that there was an increase of 3,800 Won (approximately $3.45) of lifetime profit per day increase in life span. This is evidence that care of each cow is necessary to improve net return and important for farms maintaining profitable cows. The estimates of heritability of age at first calving, first two calving intervals, days in milk for lifetime, lifespan, milk income and lifetime profit were 0.111, 0.088, 0.142, 0.140, 0.143, 0.123, and 0.102, respectively. The low heritabilities indicated that the productive life and economical traits include reproductive and productive characteristics. Age at first calving and interval between first and second calving had negative genetic correlation with lifetime profit (-0.080 and -0.265, respectively). Reducing age at first calving and first calving interval had a positive effect on lifetime profit. Lifetime profit increased to approximately 2,600,000 (2,363.6) from 800,000 Won ($727.3) when age at first calving decreased to (22.3 month) from (32.8 month). Results suggested that reproductive traits such as age at first calving and calving interval might affect various economical traits and consequently influenced productive life and profitability of cows. In conclusion, regard of the age at first calving must be taken with the optimum age at first calving for maximum lifetime profit being 22.5 to 23.5 months. Moreover, considering the negative genetic correlation of first calving interval with lifetime profit, it should be reduced against the present trend of increase.

The Effect of Age at First Calving and Calving Interval on Productive Life and Lifetime Profit in Korean Holsteins

PubMed Central

Do, Changhee; Wasana, Nidarshani; Cho, Kwanghyun; Choi, Yunho; Choi, Taejeong; Park, Byungho; Lee, Donghee

2013-01-01

This study was performed to estimate the effect of age at first calving and first two calving intervals on productive life and life time profit in Korean Holsteins. Reproduction data of Korean Holsteins born from 1998 to 2004 and lactation data from 276,573 cows with birth and last dry date that calved between 2000 and 2010 were used for the analysis. Lifetime profit increased with the days of life span. Regression of Life Span on Lifetime profit indicated that there was an increase of 3,800 Won (approximately $3.45) of lifetime profit per day increase in life span. This is evidence that care of each cow is necessary to improve net return and important for farms maintaining profitable cows. The estimates of heritability of age at first calving, first two calving intervals, days in milk for lifetime, lifespan, milk income and lifetime profit were 0.111, 0.088, 0.142, 0.140, 0.143, 0.123, and 0.102, respectively. The low heritabilities indicated that the productive life and economical traits include reproductive and productive characteristics. Age at first calving and interval between first and second calving had negative genetic correlation with lifetime profit (−0.080 and −0.265, respectively). Reducing age at first calving and first calving interval had a positive effect on lifetime profit. Lifetime profit increased to approximately 2,600,000 (2,363.6) from 800,000 Won ($727.3) when age at first calving decreased to (22.3 month) from (32.8 month). Results suggested that reproductive traits such as age at first calving and calving interval might affect various economical traits and consequently influenced productive life and profitability of cows. In conclusion, regard of the age at first calving must be taken with the optimum age at first calving for maximum lifetime profit being 22.5 to 23.5 months. Moreover, considering the negative genetic correlation of first calving interval with lifetime profit, it should be reduced against the present trend of increase

Changes in Acoustic Characteristics of the Voice across the Life Span: Measures from Individuals 4-93 Years of Age

ERIC Educational Resources Information Center

Stathopoulos, Elaine T.; Huber, Jessica E.; Sussman, Joan E.

2011-01-01

Purpose: The purpose of the present investigation was to examine acoustic voice changes across the life span. Previous voice production investigations used small numbers of participants, had limited age ranges, and produced contradictory results. Method: Voice recordings were made from 192 male and female participants 4-93 years of age. Acoustic…

CALHM1 Deletion in Mice Affects Glossopharyngeal Taste Responses, Food Intake, Body Weight, and Life Span

PubMed Central

Schmolling, Jared; Marambaud, Philippe; Rose-Hellekant, Teresa A.

2015-01-01

Stimulation of Type II taste receptor cells (TRCs) with T1R taste receptors causes sweet or umami taste, whereas T2Rs elicit bitter taste. Type II TRCs contain the calcium channel, calcium homeostasis modulator protein 1 (CALHM1), which releases adenosine triphosphate (ATP) transmitter to taste fibers. We have previously demonstrated with chorda tympani nerve recordings and two-bottle preference (TBP) tests that mice with genetically deleted Calhm1 (knockout [KO]) have severely impaired perception of sweet, bitter, and umami compounds, whereas their sour and salty tasting ability is unaltered. Here, we present data from KO mice of effects on glossopharyngeal (NG) nerve responses, TBP, food intake, body weight, and life span. KO mice have no NG response to sweet and a suppressed response to bitter compared with control (wild-type [WT]) mice. KO mice showed some NG response to umami, suggesting that umami taste involves both CALHM1- and non-CALHM1-modulated signals. NG responses to sour and salty were not significantly different between KO and WT mice. Behavioral data conformed in general with the NG data. Adult KO mice consumed less food, weighed significantly less, and lived almost a year longer than WT mice. Taken together, these data demonstrate that sweet taste majorly influences food intake, body weight, and life span. PMID:25855639

Younger and older adults' beliefs about the experience and expression of emotions across the life span.

PubMed

Montepare, Joann M; Dobish, Heidi

2014-11-01

Although theorists acknowledge that beliefs about emotions may play a role in age-related emotion behavior, no research has explored these beliefs. This research examined beliefs about the experience and expression of emotions across the life span, especially across the adult years. Younger and older adults rated the extent to which infants, children, adolescents, young adults, middle-aged adults, and older adults were likely to experience and express a range of emotions. Younger and older adults held similar beliefs about the course of emotions across the life span. Moreover, these beliefs differed across emotion categories. In particular, although older adults were believed to experience and express fewer highly charged, negative emotions, they were expected to be more likely to experience and express positive, low arousal emotions, as well as negative, low arousal emotions. The experience and expression of positive, high arousal emotions were seen as more characteristic of very young age groups as opposed to older age groups. These findings beg questions about if and how beliefs about emotion may affect age-related emotion regulation strategies and other everyday emotion-focused behaviors, as well as social reactions to older adults observed experiencing and expressing particular types of emotions. © The Author 2013. 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.

Relation of behaviour and macrophage function to life span in a murine model of premature immunosenescence.

PubMed

Guayerbas, Noelia; Catalán, Marina; Víctor, Víctor M; Miquel, Jaime; De la Fuente, Mónica

2002-08-21

According to our previous work, mice of the same strain and age show striking inter-individual differences in behaviour when exposed to a T-maze test. Further, the animals exploring the maze slowly (slow mice) or staying at the starting point (freezing behaviour), which show high levels of emotionality/anxiety in other standard behavioural tests, have a less competent immune system (earlier immunosenescence) than those which explore it quickly (fast mice). The present longitudinal study on OF-1 Swiss female mice confirms and extends the above findings. Thus, the animals showing a lower performance in the T-test (slow mice) which is accompanied by a poor neuromuscular coordination in a tightrope test, have a shorter life span than the good performers (fast mice). Moreover, the slow mice have a less competent immune system as regards the following functions of peritoneal macrophages: adherence to substrate, chemotaxis, ingestion of particles and superoxide anion production. This suggests that, at the same chronological age and as regards their immune competence, the slow mice are biologically older than the fast mice. This agrees with current ideas on the close functional relationship between the nervous and the immune system in the physiological adaptation to stress, and supports the concept that an optimum level of performance of these two systems is needed to attain a long life span. Copyright 2002 Elsevier Science B.V.

Loss of Ubp3 increases silencing, decreases unequal recombination in rDNA, and shortens the replicative life span in Saccharomyces cerevisiae.

PubMed

Oling, David; Masoom, Rehan; Kvint, Kristian

2014-06-15

Ubp3 is a conserved ubiquitin protease that acts as an antisilencing factor in MAT and telomeric regions. Here we show that ubp3∆ mutants also display increased silencing in ribosomal DNA (rDNA). Consistent with this, RNA polymerase II occupancy is lower in cells lacking Ubp3 than in wild-type cells in all heterochromatic regions. Moreover, in a ubp3∆ mutant, unequal recombination in rDNA is highly suppressed. We present genetic evidence that this effect on rDNA recombination, but not silencing, is entirely dependent on the silencing factor Sir2. Further, ubp3∆ sir2∆ mutants age prematurely at the same rate as sir2∆ mutants. Thus our data suggest that recombination negatively influences replicative life span more so than silencing. However, in ubp3∆ mutants, recombination is not a prerequisite for aging, since cells lacking Ubp3 have a shorter life span than isogenic wild-type cells. We discuss the data in view of different models on how silencing and unequal recombination affect replicative life span and the role of Ubp3 in these processes. © 2014 Öling et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Auditory Environment Across the Life Span of Cochlear Implant Users: Insights From Data Logging.

PubMed

Busch, Tobias; Vanpoucke, Filiep; van Wieringen, Astrid

2017-05-24

We describe the natural auditory environment of people with cochlear implants (CIs), how it changes across the life span, and how it varies between individuals. We performed a retrospective cross-sectional analysis of Cochlear Nucleus 6 CI sound-processor data logs. The logs were obtained from 1,501 people with CIs (ages 0-96 years). They covered over 2.4 million hr of implant use and indicated how much time the CI users had spent in various acoustical environments. We investigated exposure to spoken language, noise, music, and quiet, and analyzed variation between age groups, users, and countries. CI users spent a substantial part of their daily life in noisy environments. As a consequence, most speech was presented in background noise. We found significant differences between age groups for all auditory scenes. Yet even within the same age group and country, variability between individuals was substantial. Regardless of their age, people with CIs face challenging acoustical environments in their daily life. Our results underline the importance of supporting them with assistive listening technology. Moreover, we found large differences between individuals' auditory diets that might contribute to differences in rehabilitation outcomes. Their causes and effects should be investigated further.

View of central lift span truss web of Tensaw River ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of central lift span truss web of Tensaw River Bridge, showing support girders for life house, looking east - Tensaw River Lift Bridge, Spanning Tensaw River at U.S. Highway 90, Mobile, Mobile County, AL

Assimilation of Endogenous Nicotinamide Riboside Is Essential for Calorie Restriction-mediated Life Span Extension in Saccharomyces cerevisiae*

PubMed Central

Lu, Shu-Ping; Kato, Michiko; Lin, Su-Ju

2009-01-01

NAD+ (nicotinamide adenine dinucleotide) is an essential cofactor involved in various biological processes including calorie restriction-mediated life span extension. Administration of nicotinamide riboside (NmR) has been shown to ameliorate deficiencies related to aberrant NAD+ metabolism in both yeast and mammalian cells. However, the biological role of endogenous NmR remains unclear. Here we demonstrate that salvaging endogenous NmR is an integral part of NAD+ metabolism. A balanced NmR salvage cycle is essential for calorie restriction-induced life span extension and stress resistance in yeast. Our results also suggest that partitioning of the pyridine nucleotide flux between the classical salvage cycle and the NmR salvage branch might be modulated by the NAD+-dependent Sir2 deacetylase. Furthermore, two novel deamidation steps leading to nicotinic acid mononucleotide and nicotinic acid riboside production are also uncovered that further underscore the complexity and flexibility of NAD+ metabolism. In addition, utilization of extracellular nicotinamide mononucleotide requires prior conversion to NmR mediated by a periplasmic phosphatase Pho5. Conversion to NmR may thus represent a strategy for the transport and assimilation of large nonpermeable NAD+ precursors. Together, our studies provide a molecular basis for how NAD+ homeostasis factors confer metabolic flexibility. PMID:19416965

Assimilation of endogenous nicotinamide riboside is essential for calorie restriction-mediated life span extension in Saccharomyces cerevisiae.

PubMed

Lu, Shu-Ping; Kato, Michiko; Lin, Su-Ju

2009-06-19

NAD(+) (nicotinamide adenine dinucleotide) is an essential cofactor involved in various biological processes including calorie restriction-mediated life span extension. Administration of nicotinamide riboside (NmR) has been shown to ameliorate deficiencies related to aberrant NAD(+) metabolism in both yeast and mammalian cells. However, the biological role of endogenous NmR remains unclear. Here we demonstrate that salvaging endogenous NmR is an integral part of NAD(+) metabolism. A balanced NmR salvage cycle is essential for calorie restriction-induced life span extension and stress resistance in yeast. Our results also suggest that partitioning of the pyridine nucleotide flux between the classical salvage cycle and the NmR salvage branch might be modulated by the NAD(+)-dependent Sir2 deacetylase. Furthermore, two novel deamidation steps leading to nicotinic acid mononucleotide and nicotinic acid riboside production are also uncovered that further underscore the complexity and flexibility of NAD(+) metabolism. In addition, utilization of extracellular nicotinamide mononucleotide requires prior conversion to NmR mediated by a periplasmic phosphatase Pho5. Conversion to NmR may thus represent a strategy for the transport and assimilation of large nonpermeable NAD(+) precursors. Together, our studies provide a molecular basis for how NAD(+) homeostasis factors confer metabolic flexibility.

Personality, self-rated health, and subjective age in a life-span sample: the moderating role of chronological age.

PubMed

Stephan, Yannick; Demulier, Virginie; Terracciano, Antonio

2012-12-01

The present study tested whether chronological age moderates the association between subjective age and self-rated health and personality in a community-dwelling life-span sample (N = 1,016; age range: 18-91 years). Self-rated health, extraversion, and openness to experience were associated with a younger subjective age at older ages. Conscientious individuals felt more mature early in life. Conscientiousness, neuroticism, and agreeableness were not related to subjective age at older ages. These findings suggest that with aging self-rated health and personality traits are increasingly important for subjective age. 2013 APA, all rights reserved

Rapid weight gain after birth predicts life history and reproductive strategy in Filipino males

PubMed Central

Kuzawa, Christopher W.; McDade, Thomas W.; Adair, Linda S.; Lee, Nanette

2010-01-01

Ecological cues during prenatal and postnatal development may allow organisms to adjust reproductive strategy. The hypothalamic-pituitary-gonadal (HPG) axis is a prime candidate for adaptive plasticity as a result of its critical period of birth to 6 mo (B6M) in humans and the role of testosterone in the development and maintenance of costly sexually dimorphic somatic and behavioral traits. We hypothesized that weight velocity specific to B6M would predict male life history characteristics, including maturational timing, reproductive hormones, adult size, strength, and sexual activity. Data come from 770 Filipino men (age 20.5–22.5 y) followed since birth, with predictor variables including birth weight and weight velocities calculated at 6-mo intervals during the first 2 y of life. As expected, infants who were breastfed experienced less diarrhea, lived in wealthier households with better hygiene, and grew faster from B6M. Males with rapid B6M growth reached puberty earlier and, as young adults, had higher testosterone levels, were taller, more muscular, and had higher grip strength. They also had sex earlier and were more likely to report having had sex in the past month, resulting in more lifetime sex partners. Relationships between B6M weight gain and physical outcomes were generally not present or weaker in female subjects. We conclude that rapid weight gain specific to the brief postnatal hypothalamic-pituitary-gonadal critical period predicts early maturation and sexual activity, elevated hormone production, and more costly adult somatic characteristics among the male subjects in this sample. These findings provide evidence for early life developmental plasticity in male life history and reproductive strategy in humans. PMID:20837542

Genetic manipulation of longevity-related genes as a tool to regulate yeast life span and metabolite production during winemaking.

PubMed

Orozco, Helena; Matallana, Emilia; Aranda, Agustín

2013-01-02

Yeast viability and vitality are essential for different industrial processes where the yeast Saccharomyces cerevisiae is used as a biotechnological tool. Therefore, the decline of yeast biological functions during aging may compromise their successful biotechnological use. Life span is controlled by a variety of molecular mechanisms, many of which are connected to stress tolerance and genomic stability, although the metabolic status of a cell has proven a main factor affecting its longevity. Acetic acid and ethanol accumulation shorten chronological life span (CLS), while glycerol extends it. Different age-related gene classes have been modified by deletion or overexpression to test their role in longevity and metabolism. Overexpression of histone deacetylase SIR2 extends CLS and reduces acetate production, while overexpression of SIR2 homolog HST3 shortens CLS, increases the ethanol level, and reduces acetic acid production. HST3 overexpression also enhances ethanol tolerance. Increasing tolerance to oxidative stress by superoxide dismutase SOD2 overexpression has only a moderate positive effect on CLS. CLS during grape juice fermentation has also been studied for mutants on several mRNA binding proteins that are regulators of gene expression at the posttranscriptional level; we found that NGR1 and UTH4 deletions decrease CLS, while PUF3 and PUB1 deletions increase it. Besides, the pub1Δ mutation increases glycerol production and blocks stress granule formation during grape juice fermentation. Surprisingly, factors relating to apoptosis, such as caspase Yca1 or apoptosis-inducing factor Aif1, play a positive role in yeast longevity during winemaking as their deletions shorten CLS. Manipulation of regulators of gene expression at both transcriptional (i.e., sirtuins) and posttranscriptional (i.e., mRNA binding protein Pub1) levels allows to modulate yeast life span during its biotechnological use. Due to links between aging and metabolism, it also influences the

Reproduction and monogamy in captive flock of greater flamingos (Phoenicopterus Roseus).

PubMed

Sandri, Camillo; Sammarini, Carolina; Regaiolli, Barbara; Spiezio, Caterina; Piccirillo, Alessandra

2018-01-01

Due to the great number of greater flamingos in captivity and their long life span, studying their behavior and welfare might be useful to improve the husbandry and breeding of this species in zoos. This study aimed to investigate factors affecting the breeding activity of captive greater flamingos (Phoenicopterus roseus) from 2012 to 2016. To estimate reproductive success, the number of pairs, eggs laid, and hatchlings were recorded. In addition, information on age, egg-laying history of the partners, and pair composition was collected. An increase in the number of pairs, eggs, and hatchlings was reported over the years. For each breeding season, there were pairs who laid more than once, especially in 2014 and 2015. Approximately 50% of pairs were monogamous between consecutive years; however, the percentage dropped gradually when comparing nonconsecutive years. Senescence and previous experience seemed to affect the reproductive success of the study flamingos. In conclusion, different factors can influence the reproduction of greater flamingos in zoos. All these factors are related to nonhuman animal welfare and need to be considered in developing and improving management practices.

Life tables and reproductive parameters of Lutzomyia spinicrassa (Diptera: Psychodidae) under laboratory conditions.

PubMed

Escovar, Jesús; Bello, Felio J; Morales, Alberto; Moncada, Ligia; Cárdenas, Estrella

2004-10-01

Lutzomyia spinicrassa is a vector of Leishmania braziliensis in Colombia. This sand fly has a broad geographical distribution in Colombia and Venezuela and it is found mainly in coffee plantations. Baseline biological growth data of L. spinicrassa were obtained under experimental laboratory conditions. The development time from egg to adult ranged from 59 to 121 days, with 12.74 weeks in average. Based on cohorts of 100 females, horizontal life table was constructed. The following predictive parameters were obtained: net rate of reproduction (8.4 females per cohort female), generation time (12.74 weeks), intrinsic rate of population increase (0.17), and finite rate of population increment (1.18). The reproductive value for each class age of the cohort females was calculated. Vertical life tables were elaborated and mortality was described for the generation obtained of the field cohort. In addition, for two successive generations, additive variance and heritability for fecundity were estimated.

Tradeoffs in basal area growth and reproduction shift over the lifetime of a long-lived tropical species.

PubMed

Staudhammer, Christina L; Wadt, Lúcia H O; Kainer, Karen A

2013-09-01

Understanding of the extent to which reproductive costs drive growth largely derives from reproductively mature temperate trees in masting and non-masting years. We modeled basal area increment (BAI) and explored current growth-reproduction tradeoffs and changes in such allocation over the life span of a long-lived, non-masting tropical tree. We integrated rainfall and soil variables with data from 190 Bertholletia excelsa trees of different diameter at breast height (DBH) sizes, crown characteristics, and liana loads, quantifying BAI and reproductive output over 4 and 6 years, respectively. While rainfall explains BAI in all models, regardless of DBH class or ontogenic stage, light (based on canopy position and crown form) is most critical in the juvenile (5 cm ≤ DBH < 50 cm) phase. Suppressed trees are only present as juveniles and grow ten times slower (1.45 ± 2.73 m(2) year(-1)) than trees in dominant and co-dominant positions (13.25 ± 0.82 and 12.90 ± 1.35 m(2) year(-1), respectively). Additionally, few juvenile trees are reproductive, and those that are, demonstrate reduced growth, as do reproductive trees in the next 50 to 100 cm DBH class, suggesting growth-reproduction tradeoffs. Upon reaching the canopy, however, and attaining a sizeable girth, this pattern gradually shifts to one where BAI and reproduction are influenced independently by variables such as liana load, crown size and soil properties. At this stage, BAI is largely unaffected by fruit production levels. Thus, while growth-reproduction tradeoffs clearly exist during early life stages, effects of reproductive allocation diminish as B. excelsa increases in size and maturity.

Comparing the Developmental Genetics of Cognition and Personality over the Life Span.

PubMed

Briley, Daniel A; Tucker-Drob, Elliot M

2017-02-01

Empirical studies of cognitive ability and personality have tended to operate in isolation of one another. We suggest that returning to a unified approach to considering the development of individual differences in both cognition and personality can enrich our understanding of human development. We draw on previous meta-analyses of longitudinal, behavior genetic studies of cognition and personality across the life span, focusing particular attention on age trends in heritability and differential stability. Both cognition and personality are moderately heritable and exhibit large increases in stability with age; however, marked differences are evident. First, the heritability of cognition increases substantially with child age, while the heritability of personality decreases modestly with age. Second, increasing stability of cognition with age is overwhelmingly mediated by genetic factors, whereas increasing stability of personality with age is entirely mediated by environmental factors. Third, the maturational time-course of stability differs: Stability of cognition nears its asymptote by the end of the first decade of life, whereas stability of personality takes three decades to near its asymptote. We discuss how proximal gene-environment dynamics, developmental processes, broad social contexts, and evolutionary pressures may intersect to give rise to these divergent patterns. © 2015 Wiley Periodicals, Inc.

Effects of shortened host life span on the evolution of parasite life history and virulence in a microbial host-parasite system

PubMed Central

Nidelet, Thibault; Koella, Jacob C; Kaltz, Oliver

2009-01-01

Background Ecological factors play an important role in the evolution of parasite exploitation strategies. A common prediction is that, as shorter host life span reduces future opportunities of transmission, parasites compensate with an evolutionary shift towards earlier transmission. They may grow more rapidly within the host, have a shorter latency time and, consequently, be more virulent. Thus, increased extrinsic (i.e., not caused by the parasite) host mortality leads to the evolution of more virulent parasites. To test these predictions, we performed a serial transfer experiment, using the protozoan Paramecium caudatum and its bacterial parasite Holospora undulata. We simulated variation in host life span by killing hosts after 11 (early killing) or 14 (late killing) days post inoculation; after killing, parasite transmission stages were collected and used for a new infection cycle. Results After 13 cycles (≈ 300 generations), parasites from the early-killing treatment were less infectious, but had shorter latency time and higher virulence than those from the late-killing treatment. Overall, shorter latency time was associated with higher parasite loads and thus presumably with more rapid within-host replication. Conclusion The analysis of the means of the two treatments is thus consistent with theory, and suggests that evolution is constrained by trade-offs between virulence, transmission and within-host growth. In contrast, we found little evidence for such trade-offs across parasite selection lines within treatments; thus, to some extent, these traits may evolve independently. This study illustrates how environmental variation (experienced by the host) can lead to the evolution of distinct parasite strategies. PMID:19320981

Evolution of senescence in nature: physiological evolution in populations of garter snake with divergent life histories.

PubMed

Robert, Kylie A; Bronikowski, Anne M

2010-02-01

Evolutionary theories of aging are linked to life-history theory in that age-specific schedules of reproduction and survival determine the trajectory of age-specific mutation/selection balances across the life span and thus the rate of senescence. This is predicted to manifest at the organismal level in the evolution of energy allocation strategies of investing in somatic maintenance and robust stress responses in less hazardous environments in exchange for energy spent on growth and reproduction. Here we report experiments from long-studied populations of western terrestrial garter snakes (Thamnophis elegans) that reside in low and high extrinsic mortality environments, with evolved long and short life spans, respectively. Laboratory common-environment colonies of these two ecotypes were tested for a suite of physiological traits after control and stressed gestations. In offspring derived from control and corticosterone-treated dams, we measured resting metabolism; mitochondrial oxygen consumption, ATP and free radical production rates; and erythrocyte DNA damage and repair ability. We evaluated whether these aging biomarkers mirrored the evolution of life span and whether they were sensitive to stress. Neonates from the long-lived ecotype (1) were smaller, (2) consumed equal amounts of oxygen when corrected for body mass, (3) had DNA that damaged more readily but repaired more efficiently, and (4) had more efficient mitochondria and more efficient cellular antioxidant defenses than short-lived snakes. Many ecotype differences were enhanced in offspring derived from stress-treated dams, which supports the conclusion that nongenetic maternal effects may further impact the cellular stress defenses of offspring. Our findings reveal that physiological evolution underpins reptilian life histories and sheds light on the connectedness between stress response and aging pathways in wild-dwelling organisms.

Life-span socioeconomic trajectory, nativity, and cognitive aging in Mexican Americans: the Sacramento Area Latino Study on Aging.

PubMed

Haan, Mary N; Zeki Al-Hazzouri, Adina; Aiello, Allison E

2011-07-01

Early life circumstances influence health across the life span. Migration and ethnicity may modify the lifetime trajectory of socioeconomic status (SES) and lead to heterogeneity in cognitive aging in later life. We examined the effects of both lifetime socioeconomic trajectory and cumulative disadvantage from childhood through adulthood on late life cognitive performance in a 9-year cohort of 1,789 Mexican Americans aged 60-100 years in 1998-1999. Compared with those with low SES sustained over the life course, we found that those with more advantaged lifetime SES trajectories experienced fewer declines on a test of global cognitive function and a short-term verbal memory test. These associations are larger in first- and second-generation immigrant families. Heterogeneity of cognitive aging among diverse race/ethnic groups may be influenced by intergenerational changes in SES, cultural norms, and behaviors and changes in health related to changes in the social and physical environment.

Life-span Socioeconomic Trajectory, Nativity, and Cognitive Aging in Mexican Americans: The Sacramento Area Latino Study on Aging

PubMed Central

Zeki Al-Hazzouri, Adina; Aiello, Allison E.

2011-01-01

Objectives. Early life circumstances influence health across the life span. Migration and ethnicity may modify the lifetime trajectory of socioeconomic status (SES) and lead to heterogeneity in cognitive aging in later life. Methods. We examined the effects of both lifetime socioeconomic trajectory and cumulative disadvantage from childhood through adulthood on late life cognitive performance in a 9-year cohort of 1,789 Mexican Americans aged 60–100 years in 1998–1999. Results. Compared with those with low SES sustained over the life course, we found that those with more advantaged lifetime SES trajectories experienced fewer declines on a test of global cognitive function and a short-term verbal memory test. These associations are larger in first- and second-generation immigrant families. Discussion. Heterogeneity of cognitive aging among diverse race/ethnic groups may be influenced by intergenerational changes in SES, cultural norms, and behaviors and changes in health related to changes in the social and physical environment. PMID:21743044

Variation in reproductive life history traits between two populations of Blackbanded Darters (Percina nigrofasciata)

USGS Publications Warehouse

Hughey, Myra C.; Heins, David C.; Jelks, Howard L.; Ory, Bridget A.; Jordan, Frank

2012-01-01

We examined the life history of Blackbanded Darters (Percina nigrofasciata) from two streams in the Choctawhatchee River drainage, Florida, over a three-year study period. Blackbanded Darters from Turkey Creek were longer than fish from Ten Mile Creek; however, size-adjusted clutch and egg sizes were similar between populations. Larger females produced larger clutches, whereas egg size did not vary with female body size. Seasonally, clutch sizes were greater in May than in August. When contrasted with previous studies of Blackbanded Darters in Alabama and Louisiana, the reproductive season of Blackbanded Darters in Florida was unusually long, ceasing for only a few months in late fall. The reproductive season was longer in Turkey Creek than in Ten Mile Creek. Differences in thermal regime among streams may explain differences in life history traits among local and distant populations of Blackbanded Darters. This research, alone and in combination with previous studies of this species, emphasizes two main points. First, it reaffirms that life history studies based on a single locality or conducted at a single point in time may fail to capture the full range of variation in life history traits. Second, it highlights the extensive phenotypic variation found in species with broad geographic ranges. Such species lend themselves to comparative and experimental research on patterns and causes of life history variation.

[Changes in average life span of monks and nuns in Poland in the years 1950-2000].

PubMed

Jenner, Bartosz

2002-01-01

The aim of the research was to find out if healthy lifestyle influences the longevity. The group of 906 monks and 866 nuns who worked and died in Poland in the years 1950-2000 was regarded as people who conducted a healthy lifestyle. The population of adult Poles was chosen as a control group. As a result of the research it is reported that: 1) since 1950 till middle 1960's people in monasteries lived shorter than adult Poles [in the first ten years of the research the average life span of monks was 2.4 years shorter (t162 = 1.99, p = 0.047) and nuns lived 9 years shorter (t56 = 4.2, p < 0.001)], since the middle of 1970's till the end of 1980's the group in question lived as long as the general population, finally, for the last ten years of the investigated period of time people in monasteries lived longer [monks 2.5 (t219 = 2.5, p < 0.05), nuns 2.9 years longer (t209 = 4.6, p < 0.001)]; 2) since 1950's till 2000 the average life span in the investigated group of both sexes was increasing at the rate of 0.175 (t98 = 3.9, p < 0.001) years per calendar year greater than this value in the general population and there is no reason to assume that there have been differences between sexes; 3) as far as men are concerned, joining a monastery in the case of man enter into the monastery a year earlier prolongs life for about 0.1 year (F1,842 = 3.8, P one side test = 0.026). In case of women this relation was not significant (F1,804 < 0.1). The shorter life of people in monasteries after the second world war might be interpreted as a result of their socio-political situation at that time. In the course of time their standard of living and the access to medical treatment has been improving gradually, so their longevity is increasing faster. In the context of the investigated problem the most important results were obtained from the last ten years. These results indicate that healthy lifestyle prolongs life.

The Verriest Lecture: Short-wave-sensitive cone pathways across the life span

PubMed Central

Werner, John S.

2017-01-01

Structurally and functionally, the short-wave-sensitive (S) cone pathways are thought to decline more rapidly with normal aging than the middle- and long-wave-sensitive cone pathways. This would explain the celebrated results by Verriest and others demonstrating that the largest age-related color discrimination losses occur for stimuli on a tritan axis. Here, we challenge convention, arguing from psychophysical data that selective S-cone pathway losses do not cause declines in color discrimination. We show substantial declines in chromatic detection and discrimination, as well as in temporal and spatial vision tasks, that are mediated by S-cone pathways. These functional losses are not, however, unique to S-cone pathways. Finally, despite reduced photon capture by S cones, their postreceptoral pathways provide robust signals for the visual system to renormalize itself to maintain nearly stable color perception across the life span. PMID:26974914

CALHM1 Deletion in Mice Affects Glossopharyngeal Taste Responses, Food Intake, Body Weight, and Life Span.

PubMed

Hellekant, Göran; Schmolling, Jared; Marambaud, Philippe; Rose-Hellekant, Teresa A

2015-07-01

Stimulation of Type II taste receptor cells (TRCs) with T1R taste receptors causes sweet or umami taste, whereas T2Rs elicit bitter taste. Type II TRCs contain the calcium channel, calcium homeostasis modulator protein 1 (CALHM1), which releases adenosine triphosphate (ATP) transmitter to taste fibers. We have previously demonstrated with chorda tympani nerve recordings and two-bottle preference (TBP) tests that mice with genetically deleted Calhm1 (knockout [KO]) have severely impaired perception of sweet, bitter, and umami compounds, whereas their sour and salty tasting ability is unaltered. Here, we present data from KO mice of effects on glossopharyngeal (NG) nerve responses, TBP, food intake, body weight, and life span. KO mice have no NG response to sweet and a suppressed response to bitter compared with control (wild-type [WT]) mice. KO mice showed some NG response to umami, suggesting that umami taste involves both CALHM1- and non-CALHM1-modulated signals. NG responses to sour and salty were not significantly different between KO and WT mice. Behavioral data conformed in general with the NG data. Adult KO mice consumed less food, weighed significantly less, and lived almost a year longer than WT mice. Taken together, these data demonstrate that sweet taste majorly influences food intake, body weight, and life span. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Invited commentary: missing doses in the life span study of Japanese atomic bomb survivors.

PubMed

Ozasa, K; Grant, E J; Cullings, H M; Shore, R E

2013-03-15

The Life Span Study is a long-term epidemiologic cohort study of survivors of the atomic bombs dropped on Hiroshima and Nagasaki, Japan. In this issue of the Journal, Richardson et al. (Am J Epidemiol. 2013;177(6):562-568) suggest that those who died in the earliest years of follow-up were more likely to have a missing dose of radiation exposure assigned, leading to a bias in the radiation risk estimates. We show that nearly all members of the cohort had shielding information recorded before the beginning of follow-up and that much of the alleged bias that Richardson et al. describe simply reflects the geographic distribution of shielding conditions for which reliable dosimetry was impossible.

Using Age-Based Life History Data to Investigate the Life Cycle and Vulnerability of Octopus cyanea

PubMed Central

Herwig, Jade N.; Depczynski, Martial; Roberts, John D.; Semmens, Jayson M.; Gagliano, Monica; Heyward, Andrew J.

2012-01-01

Octopus cyanea is taken as an unregulated, recreationally fished species from the intertidal reefs of Ningaloo, Western Australia. Yet despite its exploitation and importance in many artisanal fisheries throughout the world, little is known about its life history, ecology and vulnerability. We used stylet increment analysis to age a wild O. cyanea population for the first time and gonad histology to examine their reproductive characteristics. O. cyanea conforms to many cephalopod life history generalisations having rapid, non-asymptotic growth, a short life-span and high levels of mortality. Males were found to mature at much younger ages and sizes than females with reproductive activity concentrated in the spring and summer months. The female dominated sex-ratios in association with female brooding behaviours also suggest that larger conspicuous females may be more prone to capture and suggests that this intertidal octopus population has the potential to be negatively impacted in an unregulated fishery. Size at age and maturity comparisons between our temperate bordering population and lower latitude Tanzanian and Hawaiian populations indicated stark differences in growth rates that correlate with water temperatures. The variability in life history traits between global populations suggests that management of O. cyanea populations should be tailored to each unique set of life history characteristics and that stylet increment analysis may provide the integrity needed to accurately assess this. PMID:22912898

Atrx deficiency induces telomere dysfunction, endocrine defects, and reduced life span

PubMed Central

Watson, L. Ashley; Solomon, Lauren A.; Li, Jennifer Ruizhe; Jiang, Yan; Edwards, Matthew; Shin-ya, Kazuo; Beier, Frank; Bérubé, Nathalie G.

2013-01-01

Human ATRX mutations are associated with cognitive deficits, developmental abnormalities, and cancer. We show that the Atrx-null embryonic mouse brain accumulates replicative damage at telomeres and pericentromeric heterochromatin, which is exacerbated by loss of p53 and linked to ATM activation. ATRX-deficient neuroprogenitors exhibited higher incidence of telomere fusions and increased sensitivity to replication stress–inducing drugs. Treatment of Atrx-null neuroprogenitors with the G-quadruplex (G4) ligand telomestatin increased DNA damage, indicating that ATRX likely aids in the replication of telomeric G4-DNA structures. Unexpectedly, mutant mice displayed reduced growth, shortened life span, lordokyphosis, cataracts, heart enlargement, and hypoglycemia, as well as reduction of mineral bone density, trabecular bone content, and subcutaneous fat. We show that a subset of these defects can be attributed to loss of ATRX in the embryonic anterior pituitary that resulted in low circulating levels of thyroxine and IGF-1. Our findings suggest that loss of ATRX increases DNA damage locally in the forebrain and anterior pituitary and causes tissue attrition and other systemic defects similar to those seen in aging. PMID:23563309

VIV analysis of pipelines under complex span conditions

NASA Astrophysics Data System (ADS)

Wang, James; Steven Wang, F.; Duan, Gang; Jukes, Paul

2009-06-01

Spans occur when a pipeline is laid on a rough undulating seabed or when upheaval buckling occurs due to constrained thermal expansion. This not only results in static and dynamic loads on the flowline at span sections, but also generates vortex induced vibration (VIV), which can lead to fatigue issues. The phenomenon, if not predicted and controlled properly, will negatively affect pipeline integrity, leading to expensive remediation and intervention work. Span analysis can be complicated by: long span lengths, a large number of spans caused by a rough seabed, and multi-span interactions. In addition, the complexity can be more onerous and challenging when soil uncertainty, concrete degradation and unknown residual lay tension are considered in the analysis. This paper describes the latest developments and a ‘state-of-the-art’ finite element analysis program that has been developed to simulate the span response of a flowline under complex boundary and loading conditions. Both VIV and direct wave loading are captured in the analysis and the results are sequentially used for the ultimate limit state (ULS) check and fatigue life calculation.

The Structure of Working Memory Abilities across the Adult Life Span

PubMed Central

Hale, Sandra; Rose, Nathan S.; Myerson, Joel; Strube, Michael J; Sommers, Mitchell; Tye-Murray, Nancy; Spehar, Brent

2010-01-01

The present study addresses three questions regarding age differences in working memory: (1) whether performance on complex span tasks decreases as a function of age at a faster rate than performance on simple span tasks; (2) whether spatial working memory decreases at a faster rate than verbal working memory; and (3) whether the structure of working memory abilities is different for different age groups. Adults, ages 20–89 (n=388), performed three simple and three complex verbal span tasks and three simple and three complex spatial memory tasks. Performance on the spatial tasks decreased at faster rates as a function of age than performance on the verbal tasks, but within each domain, performance on complex and simple span tasks decreased at the same rates. Confirmatory factor analyses revealed that domain-differentiated models yielded better fits than models involving domain-general constructs, providing further evidence of the need to distinguish verbal and spatial working memory abilities. Regardless of which domain-differentiated model was examined, and despite the faster rates of decrease in the spatial domain, age group comparisons revealed that the factor structure of working memory abilities was highly similar in younger and older adults and showed no evidence of age-related dedifferentiation. PMID:21299306

Altered Lipid Synthesis by Lack of Yeast Pah1 Phosphatidate Phosphatase Reduces Chronological Life Span*

PubMed Central

Park, Yeonhee; Han, Gil-Soo; Mileykovskaya, Eugenia; Garrett, Teresa A.; Carman, George M.

2015-01-01

In Saccharomyces cerevisiae, Pah1 phosphatidate phosphatase, which catalyzes the dephosphorylation of phosphatidate to yield diacylglycerol, plays a crucial role in the synthesis of the storage lipid triacylglycerol. This evolutionarily conserved enzyme also plays a negative regulatory role in controlling de novo membrane phospholipid synthesis through its consumption of phosphatidate. We found that the pah1Δ mutant was defective in the utilization of non-fermentable carbon sources but not in oxidative phosphorylation; the mutant did not exhibit major changes in oxygen consumption rate, mitochondrial membrane potential, F1F0-ATP synthase activity, or gross mitochondrial morphology. The pah1Δ mutant contained an almost normal complement of major mitochondrial phospholipids with some alterations in molecular species. Although oxidative phosphorylation was not compromised in the pah1Δ mutant, the cellular levels of ATP in quiescent cells were reduced by 2-fold, inversely correlating with a 4-fold increase in membrane phospholipids. In addition, the quiescent pah1Δ mutant cells had 3-fold higher levels of mitochondrial superoxide and cellular lipid hydroperoxides, had reduced activities of superoxide dismutase 2 and catalase, and were hypersensitive to hydrogen peroxide. Consequently, the pah1Δ mutant had a shortened chronological life span. In addition, the loss of Tsa1 thioredoxin peroxidase caused a synthetic growth defect with the pah1Δ mutation. The shortened chronological life span of the pah1Δ mutant along with its growth defect on non-fermentable carbon sources and hypersensitivity to hydrogen peroxide was suppressed by the loss of Dgk1 diacylglycerol kinase, indicating that the underpinning of pah1Δ mutant defects was the excess synthesis of membrane phospholipids. PMID:26338708

Stability and change: Stress responses and the shaping of behavioral phenotypes over the life span.

PubMed

Hennessy, Michael B; Kaiser, Sylvia; Tiedtke, Tobias; Sachser, Norbert

2015-01-01

In mammals, maternal signals conveyed via influences on hypothalamic-pituitary-adrenal (HPA) activity may shape behavior of the young to be better adapted for prevailing environmental conditions. However, the mother's influence extends beyond classic stress response systems. In guinea pigs, several hours (h) of separation from the mother activates not only the HPA axis, but also the innate immune system, which effects immediate behavioral change, as well as modifies behavioral responsiveness in the future. Moreover, the presence of the mother potently suppresses the behavioral consequences of this innate immune activation. These findings raise the possibility that long-term adaptive behavioral change can be mediated by the mother's influence on immune-related activity of her pups. Furthermore, the impact of social partners on physiological stress responses and their behavioral outcomes are not limited to the infantile period. A particularly crucial period for social development in male guinea pigs is that surrounding the attainment of sexual maturation. At this time, social interactions with adults can dramatically affect circulating cortisol concentrations and social behavior in ways that appear to prepare the male to best cope in its likely future social environment. Despite such multiple social influences on the behavior of guinea pigs at different ages, inter-individual differences in the magnitude of the cortisol response remain surprisingly stable over most of the life span. Together, it appears that throughout the life span, physiological stress responses may be regulated by social stimuli. These influences are hypothesized to adjust behavior for predicted environmental conditions. In addition, stable individual differences might provide a means of facilitating adaptation to less predictable conditions.

Expressions of ecological identity across the life span of eight environmental exemplars

NASA Astrophysics Data System (ADS)

Seydel, Jennifer

While there is a substantial body of literature looking at various aspects of ecological identity and factors that influence it, there has been less work done on how an individual's ecological identity changes with time. Much of that work is limited to short segments of the life span (e.g. the impact of wilderness experiences). This dissertation attempts to address this perceived gap by investigating how the ecological identity of eight environmental exemplars changed during the course of his or her life. What has emerged from this qualitative grounded theory investigation of the lives and works of Charles Darwin, John Muir, Aldo Leopold, Marjory Stoneman Douglas, Hazel Wolf, Rachel Carson, James Lovelock and E.O. Wilson are five sequential expressions of ecological identity. These 'stages' serve as a framework to explain ecological identity as a developmental process, both fluid and continuous, rather than at) end product. The development of an ecological identity is traced, through the development of five cognitive foundations and their alignment with five emotional foundations that reflect a progression from a sensory interaction and a kinship bond with nature into a deep understanding of the interconnectedness of all aspects of the planet. The findings reveal the evolution of an ecological identity and suggest the importance of looking beyond content knowledge in the nurturing of ecological attitudes, values, and lifestyles.

Childhood Adversity, Self-Esteem, and Diurnal Cortisol Profiles Across the Life Span.

PubMed

Zilioli, Samuele; Slatcher, Richard B; Chi, Peilian; Li, Xiaoming; Zhao, Junfeng; Zhao, Guoxiang

2016-09-01

Childhood adversity is associated with poor health outcomes in adulthood; the hypothalamic-pituitary-adrenal (HPA) axis has been proposed as a crucial biological intermediary of these long-term effects. Here, we tested whether childhood adversity was associated with diurnal cortisol parameters and whether this link was partially explained by self-esteem. In both adults and youths, childhood adversity was associated with lower levels of cortisol at awakening, and this association was partially driven by low self-esteem. Further, we found a significant indirect pathway through which greater adversity during childhood was linked to a flatter cortisol slope via self-esteem. Finally, youths who had a caregiver with high self-esteem experienced a steeper decline in cortisol throughout the day compared with youths whose caregiver reported low self-esteem. We conclude that self-esteem is a plausible psychological mechanism through which childhood adversity may get embedded in the activity of the HPA axis across the life span. © The Author(s) 2016.

Exposure To Harmful Workplace Practices Could Account For Inequality In Life Spans Across Different Demographic Groups.

PubMed

Goh, Joel; Pfeffer, Jeffrey; Zenios, Stefanos

2015-10-01

The existence of important socioeconomic disparities in health and mortality is a well-established fact. Many pathways have been adduced to explain inequality in life spans. In this article we examine one factor that has been somewhat neglected: People with different levels of education get sorted into jobs with different degrees of exposure to workplace attributes that contribute to poor health. We used General Social Survey data to estimate differential exposures to workplace conditions, results from a meta-analysis that estimated the effect of workplace conditions on mortality, and a model that permitted us to estimate the overall effects of workplace practices on health. We conclude that 10-38 percent of the difference in life expectancy across demographic groups can be explained by the different job conditions their members experience. Project HOPE—The People-to-People Health Foundation, Inc.

An empirical test of evolutionary theories for reproductive senescence and reproductive effort in the garter snake Thamnophis elegans.

PubMed

Sparkman, Amanda M; Arnold, Stevan J; Bronikowski, Anne M

2007-04-07

Evolutionary theory predicts that differential reproductive effort and rate of reproductive senescence will evolve under different rates of external mortality. We examine the evolutionary divergence of age-specific reproduction in two life-history ecotypes of the western terrestrial garter snake, Thamnophis elegans. We test for the signature of reproductive senescence (decreasing fecundity with age) and increasing reproductive effort with age (increasing reproductive productivity per gram female) in replicate populations of two life-history ecotypes: snakes that grow fast, mature young and have shorter lifespans, and snakes that grow slow, mature late and have long lives. The difference between life-history ecotypes is due to genetic divergence in growth rate. We find (i) reproductive success (live litter mass) increases with age in both ecotypes, but does so more rapidly in the fast-growth ecotype, (ii) reproductive failure increases with age in both ecotypes, but the proportion of reproductive failure to total reproductive output remains invariant, and (iii) reproductive effort remains constant in fast-growth individuals with age, but declines in slow-growth individuals. This illustration of increasing fecundity with age, even at the latest ages, deviates from standard expectations for reproductive senescence, as does the lack of increases in reproductive effort. We discuss our findings in light of recent theories regarding the phenomenon of increased reproduction throughout life in organisms with indeterminate growth and its potential to offset theoretical expectations for the ubiquity of senescence.

An empirical test of evolutionary theories for reproductive senescence and reproductive effort in the garter snake Thamnophis elegans

PubMed Central

Sparkman, Amanda M; Arnold, Stevan J; Bronikowski, Anne M

2007-01-01

Evolutionary theory predicts that differential reproductive effort and rate of reproductive senescence will evolve under different rates of external mortality. We examine the evolutionary divergence of age-specific reproduction in two life-history ecotypes of the western terrestrial garter snake, Thamnophis elegans. We test for the signature of reproductive senescence (decreasing fecundity with age) and increasing reproductive effort with age (increasing reproductive productivity per gram female) in replicate populations of two life-history ecotypes: snakes that grow fast, mature young and have shorter lifespans, and snakes that grow slow, mature late and have long lives. The difference between life-history ecotypes is due to genetic divergence in growth rate. We find (i) reproductive success (live litter mass) increases with age in both ecotypes, but does so more rapidly in the fast-growth ecotype, (ii) reproductive failure increases with age in both ecotypes, but the proportion of reproductive failure to total reproductive output remains invariant, and (iii) reproductive effort remains constant in fast-growth individuals with age, but declines in slow-growth individuals. This illustration of increasing fecundity with age, even at the latest ages, deviates from standard expectations for reproductive senescence, as does the lack of increases in reproductive effort. We discuss our findings in light of recent theories regarding the phenomenon of increased reproduction throughout life in organisms with indeterminate growth and its potential to offset theoretical expectations for the ubiquity of senescence. PMID:17251099

Outcome of assisted reproductive technology (ART) and subsequent self-reported life satisfaction.

PubMed

Kuivasaari-Pirinen, Paula; Koivumaa-Honkanen, Heli; Hippeläinen, Maritta; Raatikainen, Kaisa; Heinonen, Seppo

2014-01-01

To compare life satisfaction between women with successful or unsuccessful outcome after assisted reproductive treatment (ART) by taking into account the time since the last ART. Cohort study. Tertiary hospital. A total of 987 consecutive women who had undergone ART during 1996-2007 were invited and altogether 505 women participated in the study. A postal enquiry with a life satisfaction scale. Self-reported life satisfaction in respect to the time since the last ART. In general, women who achieved a live birth after ART had a significantly higher life satisfaction than those who had unsuccessful ART, especially when compared in the first three years. The difference disappeared in the time period of 6-9 years after ART. The unsuccessfully treated women who had a child by some other means before or after the unsuccessful ART had comparable life satisfaction with successfully treated women even earlier. Even if unsuccessful ART outcome is associated with subsequent lower level of life satisfaction, it does not seem to threaten the long-term wellbeing.

Outcome of Assisted Reproductive Technology (ART) and Subsequent Self-Reported Life Satisfaction

PubMed Central

Kuivasaari-Pirinen, Paula; Koivumaa-Honkanen, Heli; Hippeläinen, Maritta; Raatikainen, Kaisa; Heinonen, Seppo

2014-01-01

Objective To compare life satisfaction between women with successful or unsuccessful outcome after assisted reproductive treatment (ART) by taking into account the time since the last ART. Design Cohort study. Setting Tertiary hospital. Patients A total of 987 consecutive women who had undergone ART during 1996–2007 were invited and altogether 505 women participated in the study. Interventions A postal enquiry with a life satisfaction scale. Main Outcome Measure Self-reported life satisfaction in respect to the time since the last ART. Results In general, women who achieved a live birth after ART had a significantly higher life satisfaction than those who had unsuccessful ART, especially when compared in the first three years. The difference disappeared in the time period of 6–9 years after ART. The unsuccessfully treated women who had a child by some other means before or after the unsuccessful ART had comparable life satisfaction with successfully treated women even earlier. Conclusions Even if unsuccessful ART outcome is associated with subsequent lower level of life satisfaction, it does not seem to threaten the long-term wellbeing. PMID:25393846

The Tölz Temporal Topography Study: mapping the visual field across the life span. Part II: cognitive factors shaping visual field maps.

PubMed

Poggel, Dorothe A; Treutwein, Bernhard; Calmanti, Claudia; Strasburger, Hans

2012-08-01

Part I described the topography of visual performance over the life span. Performance decline was explained only partly by deterioration of the optical apparatus. Part II therefore examines the influence of higher visual and cognitive functions. Visual field maps for 95 healthy observers of static perimetry, double-pulse resolution (DPR), reaction times, and contrast thresholds, were correlated with measures of visual attention (alertness, divided attention, spatial cueing), visual search, and the size of the attention focus. Correlations with the attentional variables were substantial, particularly for variables of temporal processing. DPR thresholds depended on the size of the attention focus. The extraction of cognitive variables from the correlations between topographical variables and participant age substantially reduced those correlations. There is a systematic top-down influence on the aging of visual functions, particularly of temporal variables, that largely explains performance decline and the change of the topography over the life span.

A unique life history among tetrapods: An annual chameleon living mostly as an egg

PubMed Central

Karsten, Kristopher B.; Andriamandimbiarisoa, Laza N.; Fox, Stanley F.; Raxworthy, Christopher J.

2008-01-01

The ≈28,300 species of tetrapods (four-limbed vertebrates) almost exclusively have perennial life spans. Here, we report the discovery of a remarkable annual tetrapod from the arid southwest of Madagascar: the chameleon Furcifer labordi, with a posthatching life span of just 4–5 months. At the start of the active season (November), an age cohort of hatchlings emerges; larger juveniles or adults are not present. These hatchlings grow rapidly, reach sexual maturity in less than 2 months, and reproduce in January–February. After reproduction, senescence appears, and the active season concludes with population-wide adult death. Consequently, during the dry season, the entire population is represented by developing eggs that incubate for 8–9 months before synchronously hatching at the onset of the following rainy season. Remarkably, this chameleon spends more of its short annual life cycle inside the egg than outside of it. Our review of tetrapod longevity (>1,700 species) finds no others with such a short life span. These findings suggest that the notorious rapid death of chameleons in captivity may, for some species, actually represent the natural adult life span. Consequently, a new appraisal may be warranted concerning the viability of chameleon breeding programs, which could have special significance for species of conservation concern. Additionally, because F. labordi is closely related to other perennial species, this chameleon group may prove also to be especially well suited for comparative studies that focus on life history evolution and the ecological, genetic, and/or hormonal determinants of aging, longevity, and senescence. PMID:18591659

A unique life history among tetrapods: an annual chameleon living mostly as an egg.

PubMed

Karsten, Kristopher B; Andriamandimbiarisoa, Laza N; Fox, Stanley F; Raxworthy, Christopher J

2008-07-01

The approximately 28,300 species of tetrapods (four-limbed vertebrates) almost exclusively have perennial life spans. Here, we report the discovery of a remarkable annual tetrapod from the arid southwest of Madagascar: the chameleon Furcifer labordi, with a posthatching life span of just 4-5 months. At the start of the active season (November), an age cohort of hatchlings emerges; larger juveniles or adults are not present. These hatchlings grow rapidly, reach sexual maturity in less than 2 months, and reproduce in January-February. After reproduction, senescence appears, and the active season concludes with population-wide adult death. Consequently, during the dry season, the entire population is represented by developing eggs that incubate for 8-9 months before synchronously hatching at the onset of the following rainy season. Remarkably, this chameleon spends more of its short annual life cycle inside the egg than outside of it. Our review of tetrapod longevity (>1,700 species) finds no others with such a short life span. These findings suggest that the notorious rapid death of chameleons in captivity may, for some species, actually represent the natural adult life span. Consequently, a new appraisal may be warranted concerning the viability of chameleon breeding programs, which could have special significance for species of conservation concern. Additionally, because F. labordi is closely related to other perennial species, this chameleon group may prove also to be especially well suited for comparative studies that focus on life history evolution and the ecological, genetic, and/or hormonal determinants of aging, longevity, and senescence.

The endocrine-brain-aging triad where many paths meet: female reproductive hormone changes at midlife and their influence on circuits important for learning and memory.

PubMed

Koebele, Stephanie V; Bimonte-Nelson, Heather A

2017-08-01

Female mammals undergo natural fluctuations in sex steroid hormone levels throughout life. These fluctuations span from early development, to cyclic changes associated with the menstrual or estrous cycle and pregnancy, to marked hormone flux during perimenopause, and a final decline at reproductive senescence. While the transition to reproductive senescence is not yet fully understood, the vast majority of mammals experience this spontaneous, natural phenomenon with age, which has broad implications for long-lived species. Indeed, this post-reproductive life stage, and its transition, involves significant and enduring physiological changes, including considerably altered sex steroid hormone and gonadotropin profiles that impact multiple body systems, including the brain. The endocrine-brain-aging triad is especially noteworthy, as many paths meet and interact. Many of the brain regions affected by aging are also sensitive to changes in ovarian hormone levels, and aging and reproductive senescence are both associated with changes in memory performance. This review explores how menopause is related to cognitive aging, and discusses some of the key neural systems and molecular factors altered with age and reproductive hormone level changes, with an emphasis on brain regions important for learning and memory. Copyright © 2017. Published by Elsevier Inc.

COPEPOD REPRODUCTIVE STRATEGIES: LIFE-HISTORY THEORY, PHYLOGENETIC PATTERN AND INVASION OF INLAND WATERS. (R824771)

EPA Science Inventory

Abstract

Life-history theory predicts that different reproductive strategies should evolve in environments that differ in resource availability, mortality, seasonality, and in spatial or temporal variation. Within a population, the predicted optimal strategy is driven ...

Resting-State Network Topology Differentiates Task Signals across the Adult Life Span.

PubMed

Chan, Micaela Y; Alhazmi, Fahd H; Park, Denise C; Savalia, Neil K; Wig, Gagan S

2017-03-08

Brain network connectivity differs across individuals. For example, older adults exhibit less segregated resting-state subnetworks relative to younger adults (Chan et al., 2014). It has been hypothesized that individual differences in network connectivity impact the recruitment of brain areas during task execution. While recent studies have described the spatial overlap between resting-state functional correlation (RSFC) subnetworks and task-evoked activity, it is unclear whether individual variations in the connectivity pattern of a brain area (topology) relates to its activity during task execution. We report data from 238 cognitively normal participants (humans), sampled across the adult life span (20-89 years), to reveal that RSFC-based network organization systematically relates to the recruitment of brain areas across two functionally distinct tasks (visual and semantic). The functional activity of brain areas (network nodes) were characterized according to their patterns of RSFC: nodes with relatively greater connections to nodes in their own functional system ("non-connector" nodes) exhibited greater activity than nodes with relatively greater connections to nodes in other systems ("connector" nodes). This "activation selectivity" was specific to those brain systems that were central to each of the tasks. Increasing age was accompanied by less differentiated network topology and a corresponding reduction in activation selectivity (or differentiation) across relevant network nodes. The results provide evidence that connectional topology of brain areas quantified at rest relates to the functional activity of those areas during task. Based on these findings, we propose a novel network-based theory for previous reports of the "dedifferentiation" in brain activity observed in aging. SIGNIFICANCE STATEMENT Similar to other real-world networks, the organization of brain networks impacts their function. As brain network connectivity patterns differ across

Linkages between mitochondrial lipids and life history in temperate and tropical birds.

PubMed

Calhoon, Elisabeth A; Jimenez, Ana Gabriela; Harper, James M; Jurkowitz, Marianne S; Williams, Joseph B

2014-01-01

Temperate birds tend to have a fast pace of life and short life spans with high reproductive output, whereas tropical birds tend to have a slower pace of life, invest fewer resources in reproduction, and have higher adult survival rates. How these differences in life history at the organismal level are rooted in differences at the cellular level is a major focus of current research. Here, we cultured fibroblasts from phylogenetically paired tropical and temperate species, isolated mitochondria from each, and compared their mitochondrial membrane lipids. We also correlated the amounts of these lipids with an important life history parameter, clutch size. We found that tropical birds tended to have less mitochondrial lipid per cell, especially less cardiolipin per cell, suggesting that cells from tropical birds have fewer mitochondria or less inner mitochondrial membrane per cell. We also found that the mitochondria of tropical birds and the species with the smallest clutch sizes had higher amounts of plasmalogens, a lipid that could serve as an antioxidant. Overall, our findings are consistent with the idea that there are underlying molecular and cellular physiological traits that could account for the differences in whole-animal physiology between animals with different life histories.

Bmi-1 extends the life span of normal human oral keratinocytes by inhibiting the TGF-{beta} signaling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Reuben H., E-mail: rkim@dentistry.ucla.edu; UCLA Dental Research Institute, Los Angeles, CA 90095; UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA 90095

2010-10-01

We previously demonstrated that Bmi-1 extended the in vitro life span of normal human oral keratinocytes (NHOK). We now report that the prolonged life span of NHOK by Bmi-1 is, in part, due to inhibition of the TGF-{beta} signaling pathway. Serial subculture of NHOK resulted in replicative senescence and terminal differentiation and activation of TGF-{beta} signaling pathway. This was accompanied with enhanced intracellular and secreted TGF-{beta}1 levels, phosphorylation of Smad2/3, and increased expression of p15{sup INK4B} and p57{sup KIP2}. An ectopic expression of Bmi-1 in NHOK (HOK/Bmi-1) decreased the level of intracellular and secreted TGF-{beta}1 induced dephosphorylation of Smad2/3, andmore » diminished the level of p15{sup INK4B} and p57{sup KIP2}. Moreover, Bmi-1 expression led to the inhibition of TGF-{beta}-responsive promoter activity in a dose-specific manner. Knockdown of Bmi-1 in rapidly proliferating HOK/Bmi-1 and cancer cells increased the level of phosphorylated Smad2/3, p15{sup INK4B}, and p57{sup KIP2}. In addition, an exposure of senescent NHOK to TGF-{beta} receptor I kinase inhibitor or anti-TGF-{beta} antibody resulted in enhanced replicative potential of cells. Taken together, these data suggest that Bmi-1 suppresses senescence of cells by inhibiting the TGF-{beta} signaling pathway in NHOK.« less

The adaptive value of morphological, behavioural and life-history traits in reproductive female wolves.

PubMed

Stahler, Daniel R; MacNulty, Daniel R; Wayne, Robert K; vonHoldt, Bridgett; Smith, Douglas W

2013-01-01

Reproduction in social organisms is shaped by numerous morphological, behavioural and life-history traits such as body size, cooperative breeding and age of reproduction, respectively. Little is known, however, about the relative influence of these different types of traits on reproduction, particularly in the context of environmental conditions that determine their adaptive value. Here, we use 14 years of data from a long-term study of wolves (Canis lupus) in Yellowstone National Park, USA, to evaluate the relative effects of different traits and ecological factors on the reproductive performance (litter size and survival) of breeding females. At the individual level, litter size and survival improved with body mass and declined with age (c. 4-5 years). Grey-coloured females had more surviving pups than black females, which likely contributed to the maintenance of coat colour polymorphism in this system. The effect of pack size on reproductive performance was nonlinear as litter size peaked at eight wolves and then declined, and litter survival increased rapidly up to three wolves, beyond which it increased more gradually. At the population level, litter size and survival decreased with increasing wolf population size and canine distemper outbreaks. The relative influence of these different-level factors on wolf reproductive success followed individual > group > population. Body mass was the primary determinant of litter size, followed by pack size and population size. Body mass was also the main driver of litter survival, followed by pack size and disease. Reproductive gains because of larger body size and cooperative breeding may mitigate reproductive losses because of negative density dependence and disease. These findings highlight the adaptive value of large body size and sociality in promoting individual fitness in stochastic and competitive environments. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

Reproductive efficiency and shade avoidance plasticity under simulated competition.

PubMed

Fazlioglu, Fatih; Al-Namazi, Ali; Bonser, Stephen P

2016-07-01

Plant strategy and life-history theories make different predictions about reproductive efficiency under competition. While strategy theory suggests under intense competition iteroparous perennial plants delay reproduction and semelparous annuals reproduce quickly, life-history theory predicts both annual and perennial plants increase resource allocation to reproduction under intense competition. We tested (1) how simulated competition influences reproductive efficiency and competitive ability (CA) of different plant life histories and growth forms; (2) whether life history or growth form is associated with CA; (3) whether shade avoidance plasticity is connected to reproductive efficiency under simulated competition. We examined plastic responses of 11 herbaceous species representing different life histories and growth forms to simulated competition (spectral shade). We found that both annual and perennial plants invested more to reproduction under simulated competition in accordance with life-history theory predictions. There was no significant difference between competitive abilities of different life histories, but across growth forms, erect species expressed greater CA (in terms of leaf number) than other growth forms. We also found that shade avoidance plasticity can increase the reproductive efficiency by capitalizing on the early life resource acquisition and conversion of these resources into reproduction. Therefore, we suggest that a reassessment of the interpretation of shade avoidance plasticity is necessary by revealing its role in reproduction, not only in competition of plants.

Expectations about Memory Change Across the Life Span Are Impacted By Aging Stereotypes

PubMed Central

Lineweaver, Tara T.; Berger, Andrea K.; Hertzog, Christopher

2008-01-01

This study examined whether expectations about memory change with age vary for different personality types. Four adjectives from each of Hummert’s age-stereotype trait sets were selected to create 11 adjective clusters varying in both valence (positive versus negative) and relevance to memory functioning. Three hundred and seventy three participants in three age groups rated the memory abilities of target adults, defined by the adjective clusters, across the adult life span. Consistent with past studies, participants believed in age-related memory decline. However, participants rated target adults with positive personality traits as having better memory ability and less age-related memory decline than target adults with negative personality traits. This effect was larger when the traits were relevant to memory than when they were not. Finally, older participants were more strongly influenced by both the valence and the relevance of the personality descriptions than younger participants. PMID:19290748

Partial ablation of adult Drosophila insulin-producing neurons modulates glucose homeostasis and extends life span without insulin resistance.

PubMed

Haselton, Aaron; Sharmin, Effat; Schrader, Janel; Sah, Megha; Poon, Peter; Fridell, Yih-Woei C

2010-08-01

In Drosophila melanogaster (D. melanogaster), neurosecretory insulin-like peptide-producing cells (IPCs), analogous to mammalian pancreatic beta cells are involved in glucose homeostasis. Extending those findings, we have developed in the adult fly an oral glucose tolerance test and demonstrated that IPCs indeed are responsible for executing an acute glucose clearance response. To further develop D. melanogaster as a relevant system for studying age-associated metabolic disorders, we set out to determine the impact of adult-specific partial ablation of IPCs (IPC knockdown) on insulin-like peptide (ILP) action, metabolic outcomes and longevity. Interestingly, while IPC knockdown flies are hyperglycemic and glucose intolerant, these flies remain insulin sensitive as measured by peripheral glucose disposal upon insulin injection and serine phosphorylation of a key insulin-signaling molecule, Akt. Significant increases in stored glycogen and triglyceride levels as well as an elevated level of circulating lipid measured in adult IPC knockdown flies suggest profound modulation in energy metabolism. Additional physiological outcomes measured in those flies include increased resistance to starvation and impaired female fecundity. Finally, increased life span and decreased mortality rates measured in IPC knockdown flies demonstrate that it is possible to modulate ILP action in adult flies to achieve life span extension without insulin resistance. Taken together, we have established and validated an invertebrate genetic system to further investigate insulin action, metabolic homeostasis and regulation of aging regulated by adult IPCs.

Life-cycle exposure to microcystin-LR interferes with the reproductive endocrine system of male zebrafish.

PubMed

Su, Yujing; Li, Li; Hou, Jie; Wu, Ning; Lin, Wang; Li, Guangyu

2016-06-01

Recently, MC-LR reproductive toxicity drew great attention. Limited information was available on endocrine-disrupting effects of MC-LR on the reproduction system in fish. In the present study, zebrafish hatchlings (5 d post-fertilization) were exposed to 0, 0.3, 3 and 30μg/L MC-LR for 90 d until they reached sexual maturity. Male zebrafish were selected, and changes in growth and developmental parameters, testicular histological structure as well as the levels of gonadal steroid hormones were studied along with the related-gene transcriptional responses in the hypothalamic-pituitary-gonadal axis (HPG-axis). The results, for the first time, show a life cycle exposure to MC-LR causes growth inhibition, testicular damage and delayed sperm maturation. A significant decrease in T/E2 ratio indicated that MC-LR disrupted sex steroid hormones balance. The changes in transcriptional responses of HPG-axis related genes revealed that MC-LR promoted the conversion of T to E2 in circulating blood. It was also noted that vtg1 mRNA expression in the liver was up-regulated, which implied that MC-LR could induce estrogenic-like effects at environmentally relevant concentrations and long-term exposure. Our findings indicated that a life cycle exposure to MC-LR causes endocrine disruption with organic and functional damage of the testis, which might compromise the quality of life for the survivors and pose a potent threat on fish reproduction and thus population dynamics in MCs-contaminated aquatic environments. Copyright © 2016 Elsevier B.V. All rights reserved.

Age Differentiation within Gray Matter, White Matter, and between Memory and White Matter in an Adult Life Span Cohort.

PubMed

de Mooij, Susanne M M; Henson, Richard N A; Waldorp, Lourens J; Kievit, Rogier A

2018-06-20

It is well established that brain structures and cognitive functions change across the life span. A long-standing hypothesis called "age differentiation" additionally posits that the relations between cognitive functions also change with age. To date, however, evidence for age-related differentiation is mixed, and no study has examined differentiation of the relationship between brain and cognition. Here we use multigroup structural equation models (SEMs) and SEM trees to study differences within and between brain and cognition across the adult life span (18-88 years) in a large ( N > 646, closely matched across sexes), population-derived sample of healthy human adults from the Cambridge Centre for Ageing and Neuroscience (www.cam-can.org). After factor analyses of gray matter volume (from T1- and T2-weighted MRI) and white matter organization (fractional anisotropy from diffusion-weighted MRI), we found evidence for the differentiation of gray and white matter, such that the covariance between brain factors decreased with age. However, we found no evidence for age differentiation among fluid intelligence, language, and memory, suggesting a relatively stable covariance pattern among cognitive factors. Finally, we observed a specific pattern of age differentiation between brain and cognitive factors, such that a white matter factor, which loaded most strongly on the hippocampal cingulum, became less correlated with memory performance in later life. These patterns are compatible with the reorganization of cognitive functions in the face of neural decline, and/or with the emergence of specific subpopulations in old age. SIGNIFICANCE STATEMENT The theory of age differentiation posits age-related changes in the relationships among cognitive domains, either weakening (differentiation) or strengthening (dedifferentiation), but evidence for this hypothesis is mixed. Using age-varying covariance models in a large cross-sectional adult life span sample, we found age

Seasonal life history trade-offs in two leafwing butterflies: Delaying reproductive development increases life expectancy.

PubMed

McElderry, Robert M

2016-04-01

Surviving inhospitable periods or seasons may greatly affect fitness. Evidence of this exists in the prevalence of dormant stages in the life cycles of most insects. Here I focused on butterflies with distinct seasonal morphological types (not a genetic polymorphism) in which one morphological type, or form, delays reproduction until favorable conditions return, while the other form develops in an environment that favors direct reproduction. For two butterflies, Anaea aidea and A. andria, I tested the hypothesis that the development of each seasonal form involves a differential allocation of resources to survival at eclosion. I assayed differences in adult longevity among summer and winter forms in either a warm, active environment or a cool, calm environment. Winter form adults lived 40 times longer than summer form but only in calm, cool conditions. The magnitude of this difference provided compelling evidence that the winter form body plan and metabolic strategy (i.e. resource conservatism) favor long term survival. This research suggests that winter form adults maintain lowered metabolic rate, a common feature of diapause, to conserve resources and delay senescence while overwintering. Copyright © 2016 Elsevier Ltd. All rights reserved.

Social Rank, Stress, Fitness, and Life Expectancy in Wild Rabbits

NASA Astrophysics Data System (ADS)

von Holst, Dietrich; Hutzelmeyer, Hans; Kaetzke, Paul; Khaschei, Martin; Schönheiter, Ronald

Wild rabbits of the two sexes have separate linear rank orders, which are established and maintained by intensive fights. The social rank of individuals strongly influence their fitness: males and females that gain a high social rank, at least at the outset of their second breeding season, have a much higher lifetime fitness than subordinate individuals. This is because of two separate factors: a much higher fecundity and annual reproductive success and a 50% longer reproductive life span. These results are in contrast to the view in evolutionary biology that current reproduction can be increased only at the expense of future survival and/or fecundity. These concepts entail higher physiological costs in high-ranking mammals, which is not supported by our data: In wild rabbits the physiological costs of social positions are caused predominantly by differential psychosocial stress responses that are much lower in high-ranking than in low-ranking individuals.

The activity-dependent histone variant H2BE modulates the life span of olfactory neurons

PubMed Central

Santoro, Stephen W; Dulac, Catherine

2012-01-01

We have identified a replication-independent histone variant, Hist2h2be (referred to herein as H2be), which is expressed exclusively by olfactory chemosensory neurons. Levels of H2BE are heterogeneous among olfactory neurons, but stereotyped according to the identity of the co-expressed olfactory receptor (OR). Gain- and loss-of-function experiments demonstrate that changes in H2be expression affect olfactory function and OR representation in the adult olfactory epithelium. We show that H2BE expression is reduced by sensory activity and that it promotes neuronal cell death, such that inactive olfactory neurons display higher levels of the variant and shorter life spans. Post-translational modifications (PTMs) of H2BE differ from those of the canonical H2B, consistent with a role for H2BE in altering transcription. We propose a physiological function for H2be in modulating olfactory neuron population dynamics to adapt the OR repertoire to the environment. DOI: http://dx.doi.org/10.7554/eLife.00070.001 PMID:23240083

Expected value information improves financial risk taking across the adult life span.

PubMed

Samanez-Larkin, Gregory R; Wagner, Anthony D; Knutson, Brian

2011-04-01

When making decisions, individuals must often compensate for cognitive limitations, particularly in the face of advanced age. Recent findings suggest that age-related variability in striatal activity may increase financial risk-taking mistakes in older adults. In two studies, we sought to further characterize neural contributions to optimal financial risk taking and to determine whether decision aids could improve financial risk taking. In Study 1, neuroimaging analyses revealed that individuals whose mesolimbic activation correlated with the expected value estimates of a rational actor made more optimal financial decisions. In Study 2, presentation of expected value information improved decision making in both younger and older adults, but the addition of a distracting secondary task had little impact on decision quality. Remarkably, provision of expected value information improved the performance of older adults to match that of younger adults at baseline. These findings are consistent with the notion that mesolimbic circuits play a critical role in optimal choice, and imply that providing simplified information about expected value may improve financial risk taking across the adult life span.

Biological impact of auditory expertise across the life span: musicians as a model of auditory learning

PubMed Central

Strait, Dana L.; Kraus, Nina

2013-01-01

Experience-dependent characteristics of auditory function, especially with regard to speech-evoked auditory neurophysiology, have garnered increasing attention in recent years. This interest stems from both pragmatic and theoretical concerns as it bears implications for the prevention and remediation of language-based learning impairment in addition to providing insight into mechanisms engendering experience-dependent changes in human sensory function. Musicians provide an attractive model for studying the experience-dependency of auditory processing in humans due to their distinctive neural enhancements compared to nonmusicians. We have only recently begun to address whether these enhancements are observable early in life, during the initial years of music training when the auditory system is under rapid development, as well as later in life, after the onset of the aging process. Here we review neural enhancements in musically trained individuals across the life span in the context of cellular mechanisms that underlie learning, identified in animal models. Musicians’ subcortical physiologic enhancements are interpreted according to a cognitive framework for auditory learning, providing a model by which to study mechanisms of experience-dependent changes in auditory function in humans. PMID:23988583

"A general benevolence dimension that links neural, psychological, economic, and life-span data on altruistic tendencies": Correction to Hubbard et al. (2016).

PubMed

2016-10-01

Reports an error in "A general benevolence dimension that links neural, psychological, economic, and life-span data on altruistic tendencies" by Jason Hubbard, William T. Harbaugh, Sanjay Srivastava, David Degras and Ulrich Mayr ( Journal of Experimental Psychology: General , Advanced Online Publication, Aug 11, 2016, np). In the article, there was an error in the Task, Stimuli, and Procedures section. In the 1st sentence in the 6th paragraph, “Following the scanning phase, participants completed self-report questionnaires meant to reflected the Prosocial Disposition construct: the agreeableness scale from the Big F, which includes empathic concern and perspective-taking, and a scale of personality descriptive adjectives related to altruistic behavior (Wood, Nye, & Saucier, 2010).” should have read: “Following the scanning phase, participants completed self-report questionnaires that contained scales to reflect the Prosocial Disposition construct: the Big Five Inventory (BFI; John et al., 1991), from which we used the agreeableness scale to measure prosocial disposition; the Interpersonal Reactivity Index (IRI; Davis, 1980), from which we used the empathic concern and perspective-taking scales; and a scale of personality descriptive adjectives related to altruistic behavior (Wood, Nye, & Saucier, 2010).” (The following abstract of the original article appeared in record 2016-39037-001.) Individual and life span differences in charitable giving are an important economic force, yet the underlying motives are not well understood. In an adult, life span sample, we assessed manifestations of prosocial tendencies across 3 different measurement domains: (a) psychological self-report measures, (b) actual giving choices, and (c) fMRI-derived, neural indicators of “pure altruism.” The latter expressed individuals’ activity in neural valuation areas when charities received money compared to when oneself received money and thus reflected an altruistic concern for

Health Span-Extending Activity of Human Amniotic Membrane- and Adipose Tissue-Derived Stem Cells in F344 Rats

PubMed Central

Kim, Dajeong; Kyung, Jangbeen; Park, Dongsun; Choi, Ehn-Kyoung; Kim, Kwang Sei; Shin, Kyungha; Lee, Hangyoung; Shin, Il Seob; Kang, Sung Keun

2015-01-01

Aging brings about the progressive decline in cognitive function and physical activity, along with losses of stem cell population and function. Although transplantation of muscle-derived stem/progenitor cells extended the health span and life span of progeria mice, such effects in normal animals were not confirmed. Human amniotic membrane-derived mesenchymal stem cells (AMMSCs) or adipose tissue-derived mesenchymal stem cells (ADMSCs) (1 × 106 cells per rat) were intravenously transplanted to 10-month-old male F344 rats once a month throughout their lives. Transplantation of AMMSCs and ADMSCs improved cognitive and physical functions of naturally aging rats, extending life span by 23.4% and 31.3%, respectively. The stem cell therapy increased the concentration of acetylcholine and recovered neurotrophic factors in the brain and muscles, leading to restoration of microtubule-associated protein 2, cholinergic and dopaminergic nervous systems, microvessels, muscle mass, and antioxidative capacity. The results indicate that repeated transplantation of AMMSCs and ADMSCs elongate both health span and life span, which could be a starting point for antiaging or rejuvenation effects of allogeneic or autologous stem cells with minimum immune rejection. Significance This study demonstrates that repeated treatment with stem cells in normal animals has antiaging potential, extending health span and life span. Because antiaging and prolonged life span are issues currently of interest, these results are significant for readers and investigators. PMID:26315571

Health Span-Extending Activity of Human Amniotic Membrane- and Adipose Tissue-Derived Stem Cells in F344 Rats.

PubMed

Kim, Dajeong; Kyung, Jangbeen; Park, Dongsun; Choi, Ehn-Kyoung; Kim, Kwang Sei; Shin, Kyungha; Lee, Hangyoung; Shin, Il Seob; Kang, Sung Keun; Ra, Jeong Chan; Kim, Yun-Bae

2015-10-01

Aging brings about the progressive decline in cognitive function and physical activity, along with losses of stem cell population and function. Although transplantation of muscle-derived stem/progenitor cells extended the health span and life span of progeria mice, such effects in normal animals were not confirmed. Human amniotic membrane-derived mesenchymal stem cells (AMMSCs) or adipose tissue-derived mesenchymal stem cells (ADMSCs) (1×10(6) cells per rat) were intravenously transplanted to 10-month-old male F344 rats once a month throughout their lives. Transplantation of AMMSCs and ADMSCs improved cognitive and physical functions of naturally aging rats, extending life span by 23.4% and 31.3%, respectively. The stem cell therapy increased the concentration of acetylcholine and recovered neurotrophic factors in the brain and muscles, leading to restoration of microtubule-associated protein 2, cholinergic and dopaminergic nervous systems, microvessels, muscle mass, and antioxidative capacity. The results indicate that repeated transplantation of AMMSCs and ADMSCs elongate both health span and life span, which could be a starting point for antiaging or rejuvenation effects of allogeneic or autologous stem cells with minimum immune rejection. This study demonstrates that repeated treatment with stem cells in normal animals has antiaging potential, extending health span and life span. Because antiaging and prolonged life span are issues currently of interest, these results are significant for readers and investigators. ©AlphaMed Press.

Amelioration of Reproduction-Associated Oxidative Stress in a Viviparous Insect Is Critical to Prevent Reproductive Senescence

PubMed Central

Attardo, Geoffrey M.; Medlock, Jan; Aksoy, Serap

2014-01-01

Impact of reproductive processes upon female health has yielded conflicting results; particularly in relation to the role of reproduction-associated stress. We used the viviparous tsetse fly to determine if lactation, birth and involution lead to damage from oxidative stress (OS) that impairs subsequent reproductive cycles. Tsetse females carry an intrauterine larva to full term at each pregnancy cycle, and lactate to nourish them with milk secretions produced by the accessory gland ( = milk gland) organ. Unlike most K-strategists, tsetse females lack an apparent period of reproductive senescence allowing the production of 8–10 progeny over their entire life span. In a lactating female, over 47% of the maternal transcriptome is associated with the generation of milk proteins. The resulting single larval offspring weighs as much as the mother at birth. In studying this process we noted an increase in specific antioxidant enzyme (AOE) transcripts and enzymatic activity at critical times during lactation, birth and involution in the milk gland/fat body organ and the uterus. Suppression of superoxide dismutase (sod) decreased fecundity in subsequent reproductive cycles in young mothers and nearly abolished fecundity in geriatric females. Loss of fecundity was in part due to the inability of the mother to produce adequate milk to support larval growth. Longevity was also impaired after sod knockdown. Generation of OS in virgin females through exogenous treatment with hydrogen peroxide at times corresponding to pregnancy intervals reduced survival, which was exacerbated by sod knockdown. AOE expression may prevent oxidative damage associated with the generation of nutrients by the milk gland, parturition and milk gland breakdown. Our results indicate that prevention of OS is essential for females to meet the growing nutritional demands of juveniles during pregnancy and to repair the damage that occurs at birth. This process is particularly important for females to

GnRH in the Human Female Reproductive Axis.

PubMed

Limonta, Patrizia; Marelli, Marina Montagnani; Moretti, Roberta; Marzagalli, Monica; Fontana, Fabrizio; Maggi, Roberto

2018-01-01

Gonadotropin-releasing hormone (GnRH) is recognized as the central regulator of the functions of the pituitary-gonadal axis. The increasing knowledge on the mechanisms controlling the development and the function of GnRH-producing neurons is leading to a better diagnostic and therapeutic approach for hypogonadotropic hypogonadisms and for alterations of the puberty onset. During female life span, the function of the GnRH pulse generator may be affected by a number of inputs from other neuronal systems, offering alternative strategies for diagnostic and therapeutic interventions. Moreover, the identification of a GnRH/GnRH receptor system in both human ovary and endometrium has widened the spectrum of action of the peptide outside its hypothalamic functions. The pharmacological use of GnRH itself or its synthetic analogs (agonists and antagonists) provides a valid tool to either stimulate or block gonadotropin secretion and to modulate the female fertility in several reproductive disorders and in assisted reproduction technology. The use of GnRH agonists in young female patients undergoing chemotherapy is also considered a promising therapeutic approach to counteract iatrogenic ovarian failure. © 2018 Elsevier Inc. All rights reserved.

Families as Life Span Experts

ERIC Educational Resources Information Center

Brendtro, Larry K.; Mitchell, Martin L.

2011-01-01

Professionals dealing with challenging behavior frequently operate detached from the other relationships in the child's life. This narrow approach has been called the unilateral strategy based on the belief that the child's outside world can be ignored and behavior can be changed by administering specific corrective interventions. In contrast,…

Life history and reproductive ecology of the endangered Itasenpara bitterling Acheilognathus longipinnis (Cyprinidae) in the Himi region, central Japan.

PubMed

Nishio, M; Kawamoto, T; Kawakami, R; Edo, K; Yamazaki, Y

2015-09-01

The life history, reproductive ecology and habitat utilization of the Itasenpara (deepbody) bitterling Acheilognathus longipinnis were investigated in a lowland segment of the Moo River in Toyama Prefecture, central Honshu, Japan. Analysis of 1285 individuals revealed that the study population comprised a single size class, an age at maturation of 3 months and a life span of 1 year. On the basis of the growth pattern, the life cycle was divided into two stages: the juvenile stage, characterized by rapid growth, and the adult stage at which growth ceased. Spawning by A. longipinnis was recorded between early September and late October. Female A. longipinnis in the 0+ year age class began to mature when they reached a standard length (LS ) of 56·4 mm. Mature females had a large clutch size (maximum 273 eggs) and deposited highly adhesive and relatively large eggs (2·55 mm(3) ; major axis, 3·12 mm; minor axis, 1·22 mm) via a short ovipositor (mean length, 21·5 mm) into freshwater mussels. The embryos remained in the gill cavities of the freshwater mussels (used as a spawning substratum) and emerged as juveniles (LS , 9 mm). Habitat utilization during spawning was analysed using a generalized linear model. The best-fit model showed that three environmental factors (freshwater mussel availability, water depth and vegetation cover) were important variables for habitat utilization by A. longipinnis. Shallow areas (water depth, 250-330 mm) created for rice paddy management and areas with an abundance of cover were particularly effective for predator avoidance. These results suggest that maintenance of water level fluctuations corresponding with rice cultivation and the abundance of vegetation on the river bank (particularly avoidance of concrete revetments) is essential for conservation of this species under current practices for rice cultivation in Japan. © 2015 The Fisheries Society of the British Isles.

Mixed emotions across the adult life span in the United States

PubMed Central

Schneider, Stefan; Stone, Arthur A.

2015-01-01

Mixed emotions involve the co-occurrence of positive and negative affect, such that people feel happy and sad at the same time. The purpose of the present study was to investigate age-related differences in the experience of mixed emotions across the adult life span in two nationally representative samples of U.S. residents. Data collected by the Princeton Affect and Time Survey (PATS, n = 3,948) and by the 2010 Wellbeing Module of the American Time Use Survey (ATUS, n = 12,828) were analyzed. In both surveys, respondents (aged 15 years or older) provided a detailed time diary about the preceding day and rated their happiness and sadness for three of the day's episodes. From these reports, three different indices of mixed emotions were derived. Results indicated small, but robust, increases in mixed emotions with age. Linear age increases were consistently evident in both PATS and ATUS, and replicated across the different indices of mixed emotions. There was no significant evidence for curvilinear age trends in either study. Several sociodemographic factors that could plausibly explain age-differences in mixed emotions (e.g., retirement, disability) did not alter the age-effects. The present study adds to the growing literature documenting vital changes in the complexity of emotional experience over the lifespan. PMID:25894487

S-linolenoyl glutathione intake extends life-span and stress resistance via Sir-2.1 upregulation in Caenorhabditis elegans.

PubMed

Cascella, Roberta; Evangelisti, Elisa; Zampagni, Mariagioia; Becatti, Matteo; D'Adamio, Giampiero; Goti, Andrea; Liguri, Gianfranco; Fiorillo, Claudia; Cecchi, Cristina

2014-08-01

Oxidative stress has a prominent role in life-span regulation of living organisms. One of the endogenous free radical scavenger systems is associated with glutathione (GSH), the most abundant nonprotein thiol in mammalian cells, acting as a major reducing agent and in antioxidant defense by maintaining a tight control over redox status. We have recently designed a series of novel S-acyl-GSH derivatives capable of preventing amyloid oxidative stress and cholinergic dysfunction in Alzheimer disease models, upon an increase in GSH intake. In this study we show that the longevity of the wild-type N2 Caenorhabditis elegans strain was significantly enhanced by dietary supplementation with linolenoyl-SG (lin-SG) thioester with respect to the ethyl ester of GSH, linolenic acid, or vitamin E. RNA interference analysis and activity inhibition assay indicate that life-span extension was mediated by the upregulation of Sir-2.1, a NAD-dependent histone deacetylase ortholog of mammalian SIRT1. In particular, lin-SG-mediated overexpression of Sir-2.1 appears to be related to the Daf-16 (FoxO) pathway. Moreover, the lin-SG derivative protects N2 worms from the paralysis and oxidative stress induced by Aβ/H2O2 exposure. Overall, our findings put forward lin-SG thioester as an antioxidant supplement triggering sirtuin upregulation, thus opening new future perspectives for healthy aging or delayed onset of oxidative-related diseases. Copyright © 2014 Elsevier Inc. All rights reserved.

Social-emotional support, life satisfaction, and mental health on reproductive age women's health utilization, US, 2009.

PubMed

Willet, Michelle N; Hayes, Donald K; Zaha, Rebecca L; Fuddy, Loretta J

2012-12-01

To examine the associations among social-emotional support, life satisfaction, and mental health with not having a routine checkup among women of reproductive age in the US, data from the 2009 Behavioral Risk Factor Surveillance System, a population-based telephone survey of health behaviors, were analyzed among reproductive aged (18-44 years) women in the US. Prevalence estimates were calculated for not having a routine checkup in the past year with measures of social-emotional support, life satisfaction, and mental distress. Independent multivariable logistic regressions for each measure assessed not having a routine checkup within the past year with adjustment for age, race/ethnicity, education level, and health care coverage. Among women of reproductive age, 33.7 % (95 % CI 33.0-34.4) did not have a routine checkup within the past year. Factors associated with not having a routine checkup included: having social-emotional support most of the time (AOR = 1.29, 95 % CI 1.20-1.38) or sometimes or less (AOR = 1.47, 95 % CI 1.34-1.61) compared to those who reported always having the social-emotional support they need; reporting life satisfaction as being satisfied (AOR = 1.27, 95 % CI 1.19-1.36) or dissatisfied (AOR = 1.65, 95 % CI 1.43-1.91) compared to being very satisfied; and frequent mental distress (AOR = 1.19, 95 % CI 1.09-1.30) compared to those without. Women who report lower levels of social-emotional support, less life satisfaction, and frequent mental distress are less likely to see a doctor for a routine checkup. Targeted outreach that provides appropriate support are needed so these women can access clinical services to increase exposure to preventive health opportunities and improve overall health.

Reproductive Medicine in Amphibians.

PubMed

Chai, Norin

2017-05-01

Reproduction of amphibians includes ovulation, spermiation, fertilization, oviposition, larval stage and development, and metamorphosis. A problem at any stage could lead to reproductive failure. To stimulate reproduction, environmental conditions must be arranged to simulate changes in natural habits. Reproductive life history is well documented in amphibians; a thorough knowledge of this subject will aid the practitioner in diagnosis and treatment. Technologies for artificial reproduction are developing rapidly, and some protocols may be transferable to privately kept or endangered species. Reproductive tract disorders are rarely described; no bacterial or viral diseases are known that specifically target the amphibian reproductive system. Copyright © 2016 Elsevier Inc. All rights reserved.

Lignin composition is related to xylem embolism resistance and leaf life span in trees in a tropical semiarid climate.

PubMed

Lima, Taysla R A; Carvalho, Ellen C D; Martins, Fernando R; Oliveira, Rafael S; Miranda, Rafael S; Müller, Caroline S; Pereira, Luciano; Bittencourt, Paulo R L; Sobczak, Jullyana C M S M; Gomes-Filho, Enéas; Costa, Rafael C; Araújo, Francisca S

2018-05-16

Wood properties influence the leaf life span (LL) of tree crowns. As lignin is an important component of wood and the water transport system, we investigated its relationship with embolism resistance and the LL of several tree species in a seasonally dry tropical ecosystem. We determined total lignin and the monomer contents of guaiacyl (G) and syringyl (S) and related them to wood traits and xylem vulnerability to embolism (Ψ 50 ) for the most common species of the Brazilian semiarid, locally known as Caatinga. Leaf life span was negatively related to Ψ 50 and positively related to S : G, which was negatively related to Ψ 50 . This means that greater S : G increases LL by reducing Ψ 50 . Lignin content was not correlated with any variable. We found two apparently unrelated axes of drought resistance. One axis, associated with lignin monomeric composition, increases LL in the dry season as a result of lower xylem embolism vulnerability. The other, associated with wood density and stem water content, helps leafless trees to withstand drought and allows them to resprout at the end of the dry season. The monomeric composition of lignin (S : G) is therefore an important functional wood attribute affecting several key functional aspects of tropical tree species in a semiarid climate. © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

Physical Activity Throughout the Adult Life Span and Domain-Specific Cognitive Function in Old Age: A Systematic Review of Cross-Sectional and Longitudinal Data.

PubMed

Engeroff, Tobias; Ingmann, Tobias; Banzer, Winfried

2018-06-01

A growing body of literature suggests that physical activity might alleviate the age-related neurodegeneration and decline of cognitive function. However, most of this evidence is based on data investigating the association of exercise interventions or current physical activity behavior with cognitive function in elderly subjects. We performed a systematic review and hypothesize that physical activity during the adult life span is connected with maintained domain-specific cognitive functions during late adulthood defined as age 60+ years. We performed a systematic literature search up to November 2017 in PubMed, Web of Science, and Google Scholar without language limitations for studies analyzing the association of leisure physical activity during the adult life span (age 18+ years) and domain-specific cognitive functions in older adults (age 60+ years). The literature review yielded 14,294 articles and after applying inclusion and exclusion criteria, nine cross-sectional and 14 longitudinal studies were included. Moderate- and vigorous-intensity leisure physical activity was associated with global cognitive function and specific cognitive domains including executive functions and memory but not attention or working memory. Most studies assessed mid- to late-adulthood physical activity, thus information concerning the influence of young adult life-span physical activity is currently lacking. Observational evidence that moderate- and vigorous-intensity leisure physical activity is beneficially associated with maintained cognitive functions during old age is accumulating. Further studies are necessary to confirm a causal link by assessing objective physical activity data and the decline of cognitive functions at multiple time points during old age.

THE DISCOUNTED REPRODUCTIVE NUMBER FOR EPIDEMIOLOGY

PubMed Central

Reluga, Timothy C.; Medlock, Jan; Galvani, Alison

2013-01-01

The basic reproductive number, , and the effective reproductive number, , are commonly used in mathematical epidemiology as summary statistics for the size and controllability of epidemics. However, these commonly used reproductive numbers can be misleading when applied to predict pathogen evolution because they do not incorporate the impact of the timing of events in the life-history cycle of the pathogen. To study evolution problems where the host population size is changing, measures like the ultimate proliferation rate must be used. A third measure of reproductive success, which combines properties of both the basic reproductive number and the ultimate proliferation rate, is the discounted reproductive number . The discounted reproductive number is a measure of reproductive success that is an individual’s expected lifetime offspring production discounted by the background population growth rate. Here, we draw attention to the discounted reproductive number by providing an explicit definition and a systematic application framework. We describe how the discounted reproductive number overcomes the limitations of both the standard reproductive numbers and proliferation rates, and show that is closely connected to Fisher’s reproductive values for different life-history stages PMID:19364158

Relationships of leaf dark respiration to leaf nitrogen, specific leaf area and leaf life-span: a test across biomes and functional groups

Treesearch

Peter B. Reich; Michael B. Walters; David S. Ellsworth; [and others; [Editor’s note: James M.. Vose is the SRS co-author for this publication.

1998-01-01

Based on prior evidence of coordinated multiple leaf trait scaling, the authors hypothesized that variation among species in leaf dark respiration rate (Rd) should scale with variation in traits such as leaf nitrogen (N), leaf life-span, specific leaf area (SLA), and net photosynthetic capacity (Amax). However, it is not known whether such scaling, if it exists, is...

Effects of hunger state on the brain responses to food cues across the life span.

PubMed

Charbonnier, L; van Meer, F; Johnstone, A M; Crabtree, D; Buosi, W; Manios, Y; Androutsos, O; Giannopoulou, A; Viergever, M A; Smeets, P A M

2018-05-01

The abundant exposure to food cues in our environment is one of the main drivers of overconsumption. Food evaluation is important for the regulation of food intake by the brain and it's interaction with hunger state. Children are especially susceptible to food cues. Understanding the mechanisms behind this regulation in healthy individuals across the life span can help to elucidate the mechanisms underlying overconsumption and aid the development of future obesity prevention strategies. Few functional neuroimaging studies have been done in children and elderly. Furthermore, it is unknown how hunger state affects neural food cue reactivity in these groups, since this has not been examined consistently. We examined the effects of hunger state and age on the brain responses to low- and high calorie foods. On two mornings, 122 participants (17 children; 38 teens; 36 adults; 31 elderly) performed a food image viewing task while being scanned using fMRI, either fasted or sated. Hunger induced greater activation during high versus low calorie food image viewing than satiety in the bilateral dorsomedial (dmPFC) and in the right dorsolateral prefrontal cortex (dlPFC) across all age groups. There was no significant main effect of age group on high versus low calorie food image viewing and no interaction between age group and hunger state. The greater activation of the dlPFC across all age groups during high calorie food image viewing in a fasted state might reflect increased inhibitory control in response to these foods. This may underlie the ability to resist overconsumption of high calorie foods. Furthermore, increased medial prefrontal cortex activation during hunger might reflect increased reward value of high calorie foods, which declines with satiation. Further studies are needed to better understand these results. Notably, overweight and obese individuals should be included to examine whether these responses are altered by weight status across the life span. Copyright

The reproductive-cell cycle theory of aging: an update.

PubMed

Atwood, Craig S; Bowen, Richard L

2011-01-01

The Reproductive-Cell Cycle Theory posits that the hormones that regulate reproduction act in an antagonistic pleiotrophic manner to control aging via cell cycle signaling; promoting growth and development early in life in order to achieve reproduction, but later in life, in a futile attempt to maintain reproduction, become dysregulated and drive senescence. Since reproduction is the most important function of an organism from the perspective of the survival of the species, if reproductive-cell cycle signaling factors determine the rate of growth, determine the rate of development, determine the rate of reproduction, and determine the rate of senescence, then by definition they determine the rate of aging and thus lifespan. The theory is able to explain: 1) the simultaneous regulation of the rate of aging and reproduction as evidenced by the fact that environmental conditions and experimental interventions known to extend longevity are associated with decreased reproductive-cell cycle signaling factors, thereby slowing aging and preserving fertility in a hostile reproductive environment; 2) two phenomena that are closely related to species lifespan-the rate of growth and development and the ultimate size of the animal; 3). the apparent paradox that size is directly proportional to lifespan and inversely proportional to fertility between species but vice versa within a species; 4). how differing rates of reproduction between species is associated with differences in their lifespan; 5). why we develop aging-related diseases; and 6). an evolutionarily credible reason for why and how aging occurs-these hormones act in an antagonistic pleiotrophic manner via cell cycle signaling; promoting growth and development early in life in order to achieve reproduction, but later in life, in a futile attempt to maintain reproduction, become dysregulated and drive senescence (dyosis). In essence, the Reproductive-Cell Cycle Theory can explain aging in all sexually reproductive life

Ecological volatility and human evolution: a novel perspective on life history and reproductive strategy.

PubMed

Wells, Jonathan C K

2012-11-01

Humans are characterized by a suite of traits that seem to differentiate them profoundly from closely related apes such as the gorilla, chimpanzee, and orang-utan. These traits include longevity, cooperative breeding, stacking of offspring, lengthy maturation, and a complex life-course profile of adiposity. When, how, and why these traits emerged during our evolutionary history is currently attracting considerable attention. Most approaches to life history emphasize dietary energy availability and the risk of mortality as the two key stresses shaping life-history variability between and within species. The high energy costs of the large Homo brain are also seen as the central axis around which other life-history traits were reorganized. I propose that ecological volatility may have been a key stress, selecting in favor of the suite of traits in order to tolerate periods of energy scarcity, and increase reproductive output during periods of good conditions. Theses life-history adaptations may have preceded and enabled the trend toward encephalization. Copyright © 2012 Wiley Periodicals, Inc.

Evaluative ratings and attention across the life span: emotional arousal and gender.

PubMed

Ferrari, Vera; Bruno, Nicola; Chattat, Rabih; Codispoti, Maurizio

2017-04-01

This study was designed to investigate the evolution of emotional processing over the whole adult life span as a function of stimulus arousal and participants' gender. To this end, self-reported affective evaluation and attentional capture prompted by pleasant and unpleasant pictures varying in arousal were measured in a large sample of participants (n = 211) balanced by gender and equally spread across seven decades from 20 to 90 years. Results showed age differences only for affective evaluation of pleasant stimuli, with opposite patterns depending on stimulus arousal. As age increased, low-arousing pleasant cues (e.g. images of babies) were experienced as more pleasant and arousing by both males and females, whereas high-arousing stimuli (e.g. erotic images) were experienced as less pleasant only by females. In contrast, emotional pictures (both pleasant and unpleasant) were effective at capturing attention in a similar way across participants, regardless of age and gender. Taken together, these findings suggest that specific emotional cues prompt different subjective responses across different age groups, while basic mechanisms involved in attentional engagement towards both pleasant and unpleasant stimuli are preserved in healthy ageing.

Resveratrol induces mitochondrial dysfunction and decreases chronological life span of Saccharomyces cerevisiae in a glucose-dependent manner.

PubMed

Ramos-Gomez, Minerva; Olivares-Marin, Ivanna Karina; Canizal-García, Melina; González-Hernández, Juan Carlos; Nava, Gerardo M; Madrigal-Perez, Luis Alberto

2017-06-01

A broad range of health benefits have been attributed to resveratrol (RSV) supplementation in mammalian systems, including the increases in longevity. Nonetheless, despite the growing number of studies performed with RSV, the molecular mechanism by which it acts still remains unknown. Recently, it has been proposed that inhibition of the oxidative phosphorylation activity is the principal mechanism of RSV action. This mechanism suggests that RSV might induce mitochondrial dysfunction resulting in oxidative damage to cells with a concomitant decrease of cell viability and cellular life span. To prove this hypothesis, the chronological life span (CLS) of Saccharomyces cerevisiae was studied as it is accepted as an important model of oxidative damage and aging. In addition, oxygen consumption, mitochondrial membrane potential, and hydrogen peroxide (H 2 O 2 ) release were measured in order to determine the extent of mitochondrial dysfunction. The results demonstrated that the supplementation of S. cerevisiae cultures with 100 μM RSV decreased CLS in a glucose-dependent manner. At high-level glucose, RSV supplementation increased oxygen consumption during the exponential phase yeast cultures, but inhibited it in chronologically aged yeast cultures. However, at low-level glucose, oxygen consumption was inhibited in yeast cultures in the exponential phase as well as in chronologically aged cultures. Furthermore, RSV supplementation promoted the polarization of the mitochondrial membrane in both cultures. Finally, RSV decreased the release of H 2 O 2 with high-level glucose and increased it at low-level glucose. Altogether, this data supports the hypothesis that RSV supplementation decreases CLS as a result of mitochondrial dysfunction and this phenotype occurs in a glucose-dependent manner.

Chips in black boxes? Convenience life span, parafood, brandwidth, families, and co-creation.

PubMed

Jacobs, Marc

2015-11-01

Any consumer who opens a bag of potato or corn chips (or crisps in the UK) knows there is no time to waste to enjoy or share them. The convenience life span of chips is limited: it is the shelf or storage life and a very limited time once outside the bag. Many technologies converge to generate the desired effect as a black box, not only of the packaging but also of the chips themselves. The concept of paratext can be applied to printed messages on the package, including the brand name and other texts like advertising (epitexts), which can be expanded into the concept of parafood. These concepts help to discuss technological developments and interpret why this has recently become a negotiation zone for co-creation (see the Do us a flavor campaigns). They are symptoms of changing relations between production, research and development, marketing, and consumption. This paper pays special attention to back stories, underdog brand biographies and narratives about origin. The concept of brandwidth is introduced to sensitize about the limits of combining different stories about chips. A recent brand biography, a family history and a cookery book are used to discuss the phenomenon of cooking with Fritos. Together with the concepts of parafood, brandwidth and black boxes, more reflection and dialogue about the role of history and heritage in marketing put new challenging perspectives on the agenda. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assessing the burden of sexual and reproductive ill-health: questions regarding the use of disability-adjusted life years.

PubMed Central

AbouZahr, C.; Vaughan, J. P.

2000-01-01

The use of the disability-adjusted life year (DALY) as the unit in which to calculate the burden of disease associated with reproductive ill-health has given rise to considerable debate. Criticisms include the failure to address the problem of missing and inadequate epidemiological data, inability to deal adequately with co-morbidities, and lack of transparency in the process of ascribing disability weights to sexual and reproductive health conditions. Many of these criticisms could be addressed within the current DALY framework and a number of suggestions to do so are made. These suggestions include: (1) developing an international research strategy to determine the incidence and prevalence of reproductive ill-health and diseases, including the risk of long-term complications; (2) undertaking a research strategy using case studies, population-based surveillance data and longitudinal studies to identify, evaluate and utilize more of the existing national data sources on sexual and reproductive health; (3) comprehensively mapping the natural history of sexual and reproductive health conditions--in males and in females--and their sequelae, whether physical or psychological; (4) developing valuation instruments that are adaptable for both chronic and acute health states, that reflect a range of severity for each health state and can be modified to reflect prognosis; (5) undertaking a full review of the DALY methodology to determine what changes may be made to reduce sources of methodological and gender bias. Despite the many criticisms of the DALY as a measurement unit, it represents a major conceptual advance since it permits the combination of life expectancy and levels of dysfunction into a single measure. Measuring reproductive ill-health by counting deaths alone is inadequate for a proper understanding of the dimensions of the problem because of the young age of many of the deaths associated with reproductive ill-health and the large component of years lived with

Differential effects of the extracellular microenvironment on human embryonic stem cell differentiation into keratinocytes and their subsequent replicative life span.

PubMed

Movahednia, Mohammad Mehdi; Kidwai, Fahad Karim; Zou, Yu; Tong, Huei Jinn; Liu, Xiaochen; Islam, Intekhab; Toh, Wei Seong; Raghunath, Michael; Cao, Tong

2015-04-01

Culture microenvironment plays a critical role in the propagation and differentiation of human embryonic stem cells (hESCs) and their differentiated progenies. Although high efficiency of hESC differentiation to keratinocytes (hESC-Kert) has been achieved, little is known regarding the effects of early culture microenvironment and pertinent extracellular matrix (ECM) interactions during epidermal commitment on subsequent proliferative capacity of hESC-Kert. The aim of this study is to evaluate the effects of the different ECM microenvironments during hESC differentiation on subsequent replicative life span of hESC-Kert. In doing so, H1-hESCs were differentiated to keratinocytes (H1-Kert) in two differentiation systems. The first system employed autologous fibroblast feeder support, in which keratinocytes (H1-Kert(ACC)) were derived by coculture of hESCs with hESC-derived fibroblasts (H1-ebFs). The second system employed a novel decellularized matrix from H1-ebFs to create a dermoepidermal junction-like (DEJ) matrix. H1-Kert(AFF) were derived by differentiation of hESCs on the feeder-free system employing the DEJ matrix. Our study indicated that the feeder-free system with the use of DEJ matrix was more efficient in differentiation of hESCs toward epidermal progenitors. However, the feeder-free system was not sufficient to support the subsequent replicative capacity of differentiated keratinocytes. Of note, H1-Kert(AFF) showed limited replicative capacity with reduced telomere length and early cellular senescence. We further showed that the lack of cell-cell interactions during epidermal commitment led to heightened production of TGF-β1 by hESC-Kert during extended culture, which in turn was responsible for resulting in the limited replicative life span with cellular senescence of hESC-Kert derived under the feeder-free culture system. This study highlights for the first time the importance of the culture microenvironment and cell-ECM interactions during

A Widespread Chromosomal Inversion Polymorphism Contributes to a Major Life-History Transition, Local Adaptation, and Reproductive Isolation

PubMed Central

Lowry, David B.; Willis, John H.

2010-01-01

The role of chromosomal inversions in adaptation and speciation is controversial. Historically, inversions were thought to contribute to these processes either by directly causing hybrid sterility or by facilitating the maintenance of co-adapted gene complexes. Because inversions suppress recombination when heterozygous, a recently proposed local adaptation mechanism predicts that they will spread if they capture alleles at multiple loci involved in divergent adaptation to contrasting environments. Many empirical studies have found inversion polymorphisms linked to putatively adaptive phenotypes or distributed along environmental clines. However, direct involvement of an inversion in local adaptation and consequent ecological reproductive isolation has not to our knowledge been demonstrated in nature. In this study, we discovered that a chromosomal inversion polymorphism is geographically widespread, and we test the extent to which it contributes to adaptation and reproductive isolation under natural field conditions. Replicated crosses between the prezygotically reproductively isolated annual and perennial ecotypes of the yellow monkeyflower, Mimulus guttatus, revealed that alternative chromosomal inversion arrangements are associated with life-history divergence over thousands of kilometers across North America. The inversion polymorphism affected adaptive flowering time divergence and other morphological traits in all replicated crosses between four pairs of annual and perennial populations. To determine if the inversion contributes to adaptation and reproductive isolation in natural populations, we conducted a novel reciprocal transplant experiment involving outbred lines, where alternative arrangements of the inversion were reciprocally introgressed into the genetic backgrounds of each ecotype. Our results demonstrate for the first time in nature the contribution of an inversion to adaptation, an annual/perennial life-history shift, and multiple reproductive

Reproductive strategies and Islamic discourse: Malian migrants negotiate everyday life in Paris, France.

PubMed

Sargent, Carolyn F

2006-03-01

Approximately 37 thousand Malians currently reside in France as part of the West African diaspora. Primarily Muslim, both women and men confront challenges to their understandings of Islamic prohibitions and expectations, especially those addressing conjugal relations and reproduction. Biomedical policies generate marital conflicts and pose health dilemmas for women who face family and community pressures to reproduce but biomedical encouragement to limit childbearing. For many women, contraception represents a reprieve from repeated pregnancies and fatigue in spite of resistance from those who contest women's reproductive decisions as antithetical to Islam. French social workers play a particularly controversial role by introducing women to a discourse of women's rights that questions the authority of husbands and of religious doctrine. Women and men frame decisions and debate in diverse interpretations of Islam as they seek to manage the contradictions of everyday life and assert individual agency in the context of immigration and health politics.

[Genome loses all 5-methylcytosine a life span. How is this connected with accumulation of mutations during aging?].

PubMed

Mazin, A L

1993-01-01

The 5-methylcytosine (5mC) content in liver DNA has been determined for rats of different age. The rate of the 5mC loss from DNA is maximal in pre- and neonatal rats, 1.28% of reduction of the 5mC content per day, then it decreases to 0.33% and becomes minimal and constant in adult rats, 0.028% per day. During pregnancy and the first 15 days of postnatal development rat genome loses 49% of all 5mC. Within the next 45 days 15% of 5mC disappears, and during maximal rat life span, about four years, 39% of the genomic 5mC may be lost. Thus, it has been found for the first time that the animal genome loses practically all 5mC residues during the life span. Analysis of the literature data shows that for embryos the rate of the 5mC loss from DNA proves to be higher than that for adult animals by 96 times for mice, 69-for rats and 28-for cows. The rate of embryonal DNA hypomethylation may be inversely proportional to the pregnancy duration of species. In adult animals the rate inversely correlates with their maximal life span and accounts for the 5mC loss from DNA of a mouse by 0.028%, of a rat by 0.024%, of a hamster by 0.007%, of a cow by 0.004% and of a human being by 0.0005% per day. During the entire ontogenesis, the genome of a mouse loses 93% of all 5mC residues, that of a rat-101% and of a cow-88%. The age-dependent loss of 5mC from DNA is also typical for cell lines aging in vitro. It is constant, as a rule, and correlates with the number of cell population doublings (PD). The removal of all 5mC from DNA corresponds to 70-130 PD for human, 40-60 PD-for hamster and 6 PD- for mouse cells. In immortal lines the level of DNA methylation is stable or grows with age. A possible mechanism of an age-related 5mC loss from DNA is discussed. DNA hypomethylation may result from 5mC deamination directly at the moment of replicative DNA methylation and subsequent reparation of the G.T mispairs which leads to accumulation of the 5mC-->T+C substitutions in the genome with each

Dietary intake of Curcuma longa and Emblica officinalis increases life span in Drosophila melanogaster.

PubMed

Rawal, Shilpa; Singh, Pavneet; Gupta, Ayush; Mohanty, Sujata

2014-01-01

Intake of food and nutrition plays a major role in affecting aging process and longevity. However, the precise mechanisms underlying the ageing process are still unclear. To this respect, diet has been considered to be a determinant of ageing process. In order to better illustrate this, we used Drosophila melanogaster as a model and fed them orally with different concentrations of two commonly used Indian medicinal plant products, Curcuma longa (rhizome) and Emblica officinalis (fruit). The results revealed significant increase in life span of Drosophila flies on exposure to both the plant products, more efficiently by C. Longa than by E. officinalis. In order to understand whether the increase in lifespan was due to high-antioxidant properties of these medicinal plants, we performed enzymatic assays to assess the SOD and catalase activities in case of both treated and control Drosophila flies. Interestingly, the results support the free radical theory of aging as both these plant derivatives show high reactive oxygen species (ROS) scavenging activities.

Dietary Intake of Curcuma longa and Emblica officinalis Increases Life Span in Drosophila melanogaster

PubMed Central

Rawal, Shilpa; Singh, Pavneet; Gupta, Ayush; Mohanty, Sujata

2014-01-01

Intake of food and nutrition plays a major role in affecting aging process and longevity. However, the precise mechanisms underlying the ageing process are still unclear. To this respect, diet has been considered to be a determinant of ageing process. In order to better illustrate this, we used Drosophila melanogaster as a model and fed them orally with different concentrations of two commonly used Indian medicinal plant products, Curcuma longa (rhizome) and Emblica officinalis (fruit). The results revealed significant increase in life span of Drosophila flies on exposure to both the plant products, more efficiently by C. Longa than by E. officinalis. In order to understand whether the increase in lifespan was due to high-antioxidant properties of these medicinal plants, we performed enzymatic assays to assess the SOD and catalase activities in case of both treated and control Drosophila flies. Interestingly, the results support the free radical theory of aging as both these plant derivatives show high reactive oxygen species (ROS) scavenging activities. PMID:24967413

[Intention for self-change across the life span: Focusing on concern about self-change].

PubMed

Chishima, Yuta

2016-06-01

The purpose of the present study was to examine intention for self-change across the life span using measures of self-esteem, frequency of self-reflection, and concern about self-change. We hypothesized that: (a) Intention for self-change decreases with age because of increased self-esteem, decreased self-reflection and concern about self-change, and (b) Associations among self-esteem, frequency of self-reflection, and intention for self-change are mediated by concern about self-change. Participants (N = 997; age range, 15 to 69 yrs) completed an internet survey. ANOVA results suggested that intention for self-change, concern about self-change, and frequency of self-reflection decreased with age, and that self-esteem-scores increased with age. Simultaneous analysis of multiple age groups showed that for all groups of low self-esteem and frequent self-reflection promoted intention for self-change and that there were significant mediating effects for concern about self-change. Therefore, these findings supported out research hypotheses.

Protection throughout the life span: the psychoneuroimmunologic impact of Indo-Tibetan meditative and yogic practices.

PubMed

Olivo, Erin L

2009-08-01

The Indo-Tibetan tradition claims that proficiency in the suggested longevity practices of meditation, diet, and physical exercise (yoga), will result in profound anti-aging, stress-mediating and health enhancing effects. Western biomedical research has begun to demonstrate that the psychobiological states induced and cultivated by cognitive behavioral practices which are emblematic of those contained within the Indo-Tibetan tradition (hypnosis, meditation, visualization, systematic relaxation), indeed do have a profound impact on the body's protective and regulatory systems. Although continued study is necessary, much of the early research illuminating the mechanisms responsible for the life-span extending and health-enhancing effects of these cognitive behavioral practices points to the importance of their anti-inflammatory, anti-stress, and antioxidant effects as well as their impact in enhancing the production of endogenous substances that possess general longevity-enhancing, regenerative properties.

Egg Cannibalism and its Life History Consequences Vary with Life Stage, Sex, and Reproductive Status in Hippodamia convergens (Coleoptera: Coccinellidae).

PubMed

Bayoumy, Mohamed H; Michaud, J P

2015-08-01

Egg cannibalism is common in Coccinellidae, but its biological consequences have not been fully explored. We examined egg cannibalism by neonates, fourth instars, and adults of Hippodamia convergens Guerin-Meneville for effects on development, reproduction, and progeny fitness. We also tested female adults for ability to avoid cannibalizing their own eggs and first-instar larvae, and both sexes for changes in cannibalism propensity following mating, all in the presence of ad libitum food [larvae: eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), adults: Schizaphis graminum (Rondani)]. Cannibalism by neonates reduced developmental time and increased male body size. Cannibalism in the fourth instar accelerated pupation and led to the production of eggs that hatched faster, regardless of which parent cannibalized. However, egg fertility was improved only by maternal cannibalism in the fourth instar. Females recognized their own egg clusters, sometimes added eggs to them, and preferentially cannibalized nonfilial clusters. Most gravid females cannibalized a first-instar larva within 30 min, whether filial or not. Adult egg cannibalism was similar for virgin males and females, but declined after mating in males, and increased in females, although it had no effect on fecundity or fertility. Daughters of cannibal pairs were heavier than those of other mating combinations, but offspring of noncannibal parents had the fastest development. Reproductive females appeared to use egg cannibalism to reduce risk for their own eggs, increasing the number cannibalized with the number laid. Thus, egg cannibalism in coccinellids varies with life stage, sex, and reproductive condition, independent of food availability, and benefits are life stage specific. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Increased span length for the MGS long-span guardrail system.

DOT National Transportation Integrated Search

2014-12-01

Long-span guardrail systems have been recognized as an effective means of shielding low-fill culverts while : minimizing construction efforts and limiting culvert damage and repair. The current MGS long-span design provided the : capability to span u...

Fetal programming of sexual development and reproductive function.

PubMed

Zambrano, Elena; Guzmán, Carolina; Rodríguez-González, Guadalupe L; Durand-Carbajal, Marta; Nathanielsz, Peter W

2014-01-25

The recent growth of interest in developmental programming of physiological systems has generally focused on the cardiovascular system (especially hypertension) and predisposition to metabolic dysfunction (mainly obesity and diabetes). However, it is now clear that the full range of altered offspring phenotypes includes impaired reproductive function. In rats, sheep and nonhuman primates, reproductive capacity is altered by challenges experienced during critical periods of development. This review will examine available experimental evidence across commonly studied experimental species for developmental programming of female and male reproductive function throughout an individual's life-course. It is necessary to consider events that occur during fetal development, early neonatal life and prior to and during puberty, during active reproductive life and aging as reproductive performance declines. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

View of approach span and movable span, looking southeast from ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of approach span and movable span, looking southeast from navy land. Note that navigational channel exists only on north side of movable span. - Naval Supply Annex Stockton, Daggett Road Bridge, Daggett Road traversing Burns Cut Off, Stockton, San Joaquin County, CA

Identification of ligands for DAF-12 that govern dauer formation and reproduction in C. elegans.

PubMed

Motola, Daniel L; Cummins, Carolyn L; Rottiers, Veerle; Sharma, Kamalesh K; Li, Tingting; Li, Yong; Suino-Powell, Kelly; Xu, H Eric; Auchus, Richard J; Antebi, Adam; Mangelsdorf, David J

2006-03-24

In response to environmental and dietary cues, the C. elegans orphan nuclear receptor, DAF-12, regulates dauer diapause, reproductive development, fat metabolism, and life span. Despite strong evidence for hormonal control, the identification of the DAF-12 ligand has remained elusive. In this work, we identified two distinct 3-keto-cholestenoic acid metabolites of DAF-9, a cytochrome P450 involved in hormone production, that function as ligands for DAF-12. At nanomolar concentrations, these steroidal ligands (called dafachronic acids) bind and transactivate DAF-12 and rescue the hormone deficiency of daf-9 mutants. Interestingly, DAF-9 has a biochemical activity similar to mammalian CYP27A1 catalyzing addition of a terminal acid to the side chain of sterol metabolites. Together, these results define the first steroid hormones in nematodes as ligands for an invertebrate orphan nuclear receptor and demonstrate that steroidal regulation of reproduction, from biology to molecular mechanism, is conserved from worms to humans.

Age Differences in Explicit and Implicit Age Attitudes Across the Life Span.

PubMed

Chopik, William J; Giasson, Hannah L

2017-08-01

Biased judgments about others can operate both within and outside of our conscious awareness. However, little attention has been paid to how implicit and explicit attitudes differ across the life span, particularly with respect to age bias. In the current study, we examined age differences in implicit and explicit attitudes towards older individuals. Participants (N = 704,151) ranging from age 15 to 94 completed the Implicit Association Test and explicit self-report measures of bias against older adults. The associations between age bias and several demographic characteristics (e.g., gender, education) were also examined. A preference for younger people was found among participants of all ages; however, implicit and explicit attitudes showed divergent associations with age. Implicit preference for younger people was highest among older adults; explicit preference for younger people was lowest among older adults. Examining age differences in implicit and explicit attitudes sheds light into the development and complexities of aging perceptions in different age groups. The current study's findings are discussed in the context of applications to and implications of reducing prejudice toward older adults. © 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.

Tracking the trajectory of shame, guilt, and pride across the life span.

PubMed

Orth, Ulrich; Robins, Richard W; Soto, Christopher J

2010-12-01

The authors examined age differences in shame, guilt, and 2 forms of pride (authentic and hubristic) from age 13 years to age 89 years, using cross-sectional data from 2,611 individuals. Shame decreased from adolescence into middle adulthood, reaching a nadir around age 50 years, and then increased in old age. Guilt increased from adolescence into old age, reaching a plateau at about age 70 years. Authentic pride increased from adolescence into old age, whereas hubristic pride decreased from adolescence into middle adulthood, reaching a minimum around age 65 years, and then increased in old age. On average, women reported experiencing more shame and guilt; Blacks reported experiencing less shame and Asians more hubristic pride than other ethnicities. Across the life span, shame and hubristic pride tended to be negatively related to psychological well-being, and shame-free guilt and authentic pride showed positive relations with well-being. Overall, the findings support the maturity principle of personality development and suggest that as people age they become more prone to experiencing psychologically adaptive self-conscious emotions, such as guilt and authentic pride, and less prone to experiencing psychologically maladaptive ones, such as shame and hubristic pride. PsycINFO Database Record (c) 2010 APA, all rights reserved.

Reproduction impairment and endocrine disruption in female zebrafish after long-term exposure to MC-LR: A life cycle assessment.

PubMed

Hou, Jie; Li, Li; Wu, Ning; Su, Yujing; Lin, Wang; Li, Guangyu; Gu, Zemao

2016-01-01

Microcystin-LR (MC-LR) has been found to cause reproductive and developmental impairments as well as to disrupt sex hormone homeostasis of fish during acute and sub-chronic toxic experiments. However, fish in natural environments are continuously exposed to MC-LR throughout their entire life cycle as opposed to short-term exposure. Here, we tested the hypothesis that the mechanism by which MC-LR harms female fish reproduction and development within natural water bodies is through interference of the reproductive endocrine system. In the present study, zebrafish hatchlings (5 d post-fertilization) were exposed to 0, 0.3, 3 and 30 μg/L MC-LR for 90 d until reaching sexual maturity. Female zebrafish were selected, and the changes in growth and developmental indicators, ovarian ultrastructure as well as the levels of gonadal steroid hormones and vitellogenin (VTG) were examined along with the transcription of related genes in the hypothalamic-pituitary-gonadal-liver axis (HPGL-axis). The results showed for the first time, a life cycle exposure to MC-LR caused growth inhibition, decreased ovary weight and ovarian ultra-pathological lesions. Decreased ovarian testosterone levels indicated that MC-LR disrupted sex steroid hormone balance. Significantly up-regulated transcription of brain FSHβ and LHβ along with ovarian ERα, FSHR and LHR suggested positive feedback regulation in the HPGL-axis was induced as a compensatory mechanism for MC-LR damage. It was also noted that ovarian VTG content and hepatic ERα and VTG1 expression were all down-regulated, which might be responsible for reduced vitellus storage noted in our histological observations. Our findings indicate that a life cycle exposure to MC-LR impairs the development and reproduction of female zebrafish by disrupting the transcription of related HPGL-axis genes, suggesting that MC-LR has potential adverse effects on fish reproduction and thus population dynamics in MCs-contaminated aquatic environment

Long-Term Effects of Environmental Endocrine Disruptors on Reproductive Physiology and Behavior

PubMed Central

Patisaul, Heather B.; Adewale, Heather B.

2009-01-01

It is well established that, over the course of development, hormones shape the vertebrate brain such that sex specific physiology and behaviors emerge. Much of this occurs in discrete developmental windows that span gestation through the prenatal period, although it is now becoming clear that at least some of this process continues through puberty. Perturbation of this developmental progression can permanently alter the capacity for reproductive success. Wildlife studies have revealed that exposure to endocrine disrupting compounds (EDCs), either naturally occurring or man made, can profoundly alter reproductive physiology and ultimately impact entire populations. Laboratory studies in rodents and other species have elucidated some of the mechanisms by which this occurs and strongly indicate that humans are also vulnerable to disruption. Use of hormonally active compounds in human medicine has also unfortunately revealed that the developing fetus can be exposed to and affected by endocrine disruptors, and that it might take decades for adverse effects to manifest. Research within the field of environmental endocrine disruption has also contributed to the general understanding of how early life experiences can alter reproductive physiology and behavior through non-genomic, epigenetic mechanisms such as DNA methylation and histone acetylation. These types of effects have the potential to impact future generations if the germ line is affected. This review provides an overview of how exposure to EDCs, particularly those that interfere with estrogen action, impacts reproductive physiology and behaviors in vertebrates. PMID:19587848

Midwives' adoption of the reproductive life plan in contraceptive counselling: a mixed methods study.

PubMed

Stern, J; Bodin, M; Grandahl, M; Segeblad, B; Axén, L; Larsson, M; Tydén, T

2015-05-01

How is the reproductive life plan (RLP) adopted in midwifery contraceptive counselling? A majority of midwives adopted the RLP in their counselling, had predominantly positive experiences and considered it a feasible tool for promoting reproductive health. The RLP is a health-promoting tool recommended by the Centers for Disease Control and Prevention in the USA for improving preconception health. It was recently used in a clinical setting in Sweden and was found to increase women's knowledge about fertility and to influence women's wishes to have their last child earlier in life. An exploratory mixed methods study among 68 midwives who provided contraceptive counselling in primary health care to at least 20 women each during the study period. Midwives received an introduction and materials for using the RLP in contraceptive counselling. Three months later, in the spring of 2014, they were invited to complete a questionnaire and participate in a focus group interview about their adoption of the RLP. Data collection was through a questionnaire (n = 53 out of 68; participation rate 78%) and five focus group interviews (n = 22). Participants included both younger and older midwives with longer and shorter experiences of contraceptive counselling in public and private health care in one Swedish county. Quantitative data were analysed for differences between users and non-users, and qualitative data were analysed by qualitative content analysis to explore the midwives experiences and opinions of using the RLP. Sixty-eight per cent of midwives had used the RLP in their contraceptive counselling. Four categories emerged through the focus group interviews: (i) A predominantly positive experience; (ii) The RLP-a health-promoting tool; (iii) individual and societal factors influence the RLP counselling; and (4) long-term implementation comprises opportunities, risks and needs. The most common reason for not using the RLP was lack of information. There was general lack of

Life-span retrieval of public events: Reminiscence bump for high-impact events, recency for others.

PubMed

Tekcan, Ali I; Boduroglu, Aysecan; Mutlutürk, Aysu; Aktan Erciyes, Aslı

2017-10-01

Although substantial evidence exists showing a reliable reminiscence bump for personal events, data regarding retrieval distributions for public events have been equivocal. The primary aim of the present study was to address life-span retrieval distributions of different types of public events in comparison to personal events, and to test whether the existing accounts of the bump can explain the distribution of public events. We asked a large national sample to report the most important, happiest, and saddest personal events and the most important, happiest, saddest, most proud, most fearful, and most shameful public events. We found a robust bump corresponding to the third decade of life for the happiest and the most important positive but not for the saddest and most important negative personal events. For the most important public events, a bump emerged only for the two most frequently mentioned events. Distributions of public events cued with emotions were marked by recency. These results point to potential differences in retrieval of important personal and public events. While the life-script framework well accounts for the findings regarding important personal events, a chronologically retroactive search seem to guide retrieval of public events. Reminiscence bump observed for the two public events suggest that age-at-event affects recall of public events to the degree that the events are high-impact ones that dominate nation's collective memory. Results provide further evidence that the bump is not unitary and points to importance of event type and memory elicitation method with regard to competing explanations of the phenomenon.

Coral reproduction in Western Australia

PubMed Central

Speed, Conrad W.; Babcock, Russ

2016-01-01

Larval production and recruitment underpin the maintenance of coral populations, but these early life history stages are vulnerable to extreme variation in physical conditions. Environmental managers aim to minimise human impacts during significant periods of larval production and recruitment on reefs, but doing so requires knowledge of the modes and timing of coral reproduction. Most corals are hermaphroditic or gonochoric, with a brooding or broadcast spawning mode of reproduction. Brooding corals are a significant component of some reefs and produce larvae over consecutive months. Broadcast spawning corals are more common and display considerable variation in their patterns of spawning among reefs. Highly synchronous spawning can occur on reefs around Australia, particularly on the Great Barrier Reef. On Australia’s remote north-west coast there have been fewer studies of coral reproduction. The recent industrial expansion into these regions has facilitated research, but the associated data are often contained within confidential reports. Here we combine information in this grey-literature with that available publicly to update our knowledge of coral reproduction in WA, for tens of thousands of corals and hundreds of species from over a dozen reefs spanning 20° of latitude. We identified broad patterns in coral reproduction, but more detailed insights were hindered by biased sampling; most studies focused on species of Acropora sampled over a few months at several reefs. Within the existing data, there was a latitudinal gradient in spawning activity among seasons, with mass spawning during autumn occurring on all reefs (but the temperate south-west). Participation in a smaller, multi-specific spawning during spring decreased from approximately one quarter of corals on the Kimberley Oceanic reefs to little participation at Ningaloo. Within these seasons, spawning was concentrated in March and/or April, and October and/or November, depending on the timing of

The politics of reproduction.

PubMed

Ginsburg, F; Rapp, R

1991-01-01

The topic of human reproduction encompasses events throughout the human and especially female life-cycle as well as ideas and practices surrounding fertility, birth, and child care. Most of the scholarship on the subject, up through the 1960s, was based on cross-cultural surveys focused on the beliefs, norms, and values surrounding reproductive behaviors. Multiple methodologies and subspecialties, and fields like social history, human biology, and demography were utilized for the analysis. The concept of the politics of reproduction synthesizes local and global perspectives. The themes investigated include: the concept of reproduction, population control, and the internationalization of state and market interests (new reproductive technologies); social movements and contested domains; medicalization and its discontents; fertility and its control; adolescence and teen pregnancy; birth; birth attendants; the construction of infancy and the politics of child survival; rethinking the demographic transition; networks of nurturance; and meanings of menopause. The medicalization of reproduction is a central issue of studies of birth, midwifery, infertility, and reproductive technologies. Scholars have also analyzed different parts of the female life-cycle as medical problems. Other issues worth analysis include the internationalization of adoption and child care workers; the crisis of infertility of low-income and minority women who are not candidates for expensive reproductive technologies; the concerns of women at high risk for HIV whose cultural status depends on their fertility; questions of reproduction concerning, lesbians and gay men (artificial insemination and discrimination in child rearing); the study of menopause; and fatherhood. New discourse analysis is used to analyze state eugenic policies; conflicts over Western neocolonial influences in which women's status as childbearers represent nationalist interests; fundamentalist attacks on abortion rights; and

6. VIEW OF APPROACH SPAN AND MAIN SPAN OF THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. VIEW OF APPROACH SPAN AND MAIN SPAN OF THE ACCESS BRIDGE AND INTAKE PIER, LOOKING SOUTHWEST. - Sacramento River Water Treatment Plant Intake Pier & Access Bridge, Spanning Sacramento River approximately 175 feet west of eastern levee on river; roughly .5 mile downstream from confluence of Sacramento & American Rivers, Sacramento, Sacramento County, CA

Reproduction cycles and strategies of the cold-water sponges Halisarca dujardini (Demospongiae, Halisarcida), Myxilla incrustans and Iophon piceus (Demospongiae, Poecilosclerida) from the White Sea.

PubMed

Ereskovsky, A V

2000-02-01

The reproductive development of the Demospongiae species Halisarca dujardini (Halisarcida), Myxilla incrustans and Iophon piceus (Poecilosclerida) from Chupa Inlet (Kandalaksha Bay, the White Sea) was studied histologically during 1982-1994 and 1997. These species are all viviparous. Halisarca dujardini inhabits shallow waters (1.5-5 m); M. incrustans and I. piceus are common in a more stable environment at depths between 15 and 25 m. Initiation of sexual reproduction stages is dependent upon water temperature. Reproductive effort is low in Myxilla incrustans and I. piceus (reproductive elements contribute 7.3% and 12% of maternal tissue volume respectively), but much higher in H. dujardini (up to 69% of the parental tissue volume). Reproduction leads to localized destruction of maternal tissue for M. incrustans and I. piceus and complete disorder of central and basal parts of the choanosoma of H. dujardini after each period of reproduction. Myxilla incrustans and I. piceus reproduce throughout the hydrological summer, but reproduction in H. dujardini is restricted to 3 weeks. The average life span of M. incrustans and I. piceus is more than 4 years, and that of H. dujardini is about 7-12 months. The data suggest that M. incrustans and I. piceus are K-strategists, whereas H. dujardini is an r-strategist.

SPAN: Ocean science

NASA Technical Reports Server (NTRS)

Thomas, Valerie L.; Koblinsky, Chester J.; Webster, Ferris; Zlotnicki, Victor; Green, James L.

1987-01-01

The Space Physics Analysis Network (SPAN) is a multi-mission, correlative data comparison network which links space and Earth science research and data analysis computers. It provides a common working environment for sharing computer resources, sharing computer peripherals, solving proprietary problems, and providing the potential for significant time and cost savings for correlative data analysis. This is one of a series of discipline-specific SPAN documents which are intended to complement the SPAN primer and SPAN Management documents. Their purpose is to provide the discipline scientists with a comprehensive set of documents to assist in the use of SPAN for discipline specific scientific research.

The nucleus- and endoplasmic reticulum-targeted forms of protein tyrosine phosphatase 61F regulate Drosophila growth, life span, and fecundity.

PubMed

Buszard, Bree J; Johnson, Travis K; Meng, Tzu-Ching; Burke, Richard; Warr, Coral G; Tiganis, Tony

2013-04-01

The protein tyrosine phosphatases (PTPs) T cell PTP (TCPTP) and PTP1B share a high level of catalytic domain sequence and structural similarity yet display distinct differences in substrate recognition and function. Their noncatalytic domains contribute to substrate selectivity and function by regulating TCPTP nucleocytoplasmic shuttling and targeting PTP1B to the endoplasmic reticulum (ER). The Drosophila TCPTP/PTP1B orthologue PTP61F has two variants with identical catalytic domains that are differentially targeted to the ER and nucleus. Here we demonstrate that the PTP61F variants differ in their ability to negatively regulate insulin signaling in vivo, with the nucleus-localized form (PTP61Fn) being more effective than the ER-localized form (PTP61Fm). We report that PTP61Fm is reliant on the adaptor protein Dock to attenuate insulin signaling in vivo. Also, we show that the PTP61F variants differ in their capacities to regulate growth, with PTP61Fn but not PTP61Fm attenuating cellular proliferation. Furthermore, we generate a mutant lacking both PTP61F variants, which displays a reduction in median life span and a decrease in female fecundity, and show that both variants are required to rescue these mutant phenotypes. Our findings define the role of PTP61F in life span and fecundity and reinforce the importance of subcellular localization in mediating PTP function in vivo.

FERTILITY INTENTIONS AND EARLY LIFE HEALTH STRESS AMONG WOMEN IN EIGHT INDIAN CITIES: TESTING THE REPRODUCTIVE ACCELERATION HYPOTHESIS.

PubMed

Kulathinal, Sangita; Säävälä, Minna

2015-09-01

In life history theory, early life adversity is associated with an accelerated reproductive tempo. In harsh and unpredictable conditions in developing societies fertility is generally higher and the reproductive tempo faster than in more secure environments. This paper examines whether differences in female anthropometry, particularly adult height, are associated with fertility intentions of women in urban environments in India. The study population consists of women aged 15-29 (N=4485) in slums and non-slums of eight Indian cities in the National Family Health Survey (NFHS) of 2005-2006. Adult height is taken as a proxy for early childhood health and nutritional condition. Fertility intentions are examined by using two variables: the desire to have a child or another child, and to have it relatively soon, as indicative of accelerated reproductive scheduling. Evidence supporting the acceleration hypothesis is found in two urban frames out of 26 examined in a two-staged multinomial logistic model. In three cases, the relationship between fertility intentions and height is the opposite than expected by the acceleration hypothesis: taller women have a higher predictive probability of desiring a(nother) child and/or narrower birth spacing. Potential explanations for the partly contradictory relationship between the childhood health indicator and fertility intentions are discussed.

The role of fecundity and reproductive effort in defining life history strategies of North American freshwater mussels

Treesearch

Wendell R. Haag

2013-01-01

Selection is expected to optimize reproductive investment resulting in characteristic trade-offs among traits such as brood size, offspring size, somatic maintenance, and lifespan; relative patterns of energy allocation to these functions are important in defining life-history strategies. Freshwater mussels are a diverse and imperiled component of aquatic ecosystems,...

Studying the Motivated Agent Through Time: Personal Goal Development During the Adult Life Span.

PubMed

Dunlop, William L; Bannon, Brittany L; McAdams, Dan P

2017-04-01

This research examined the rank-order and mean-level consistency of personal goals at two periods in the adult life span. Personal goal continuity was considered among a group of young adults (N = 145) who reported their goals three times over a 3-year period and among a group of midlife adults (N = 163) who specified their goals annually over a 4-year period. Goals were coded for a series of motive-based (viz., achievement, affiliation, intimacy, power) and domain-based (viz., finance, generativity, health, travel) categories. In both samples, we noted a moderate degree of rank-order consistency across assessment periods. In addition, the majority of goal categories exhibited a high degree of mean-level consistency. The results of this research suggest that (a) the content of goals exhibits a modest degree of rank-order consistency and a substantial degree of mean-level consistency over time, and (b) considering personality continuity and development as manifest via goals represents a viable strategy for personality psychologists. © 2015 Wiley Periodicals, Inc.

Studies of reproductive output of the desert tortoise at Joshua Tree National Park, the Mojave National Preserve, and comparative sites

USGS Publications Warehouse

Lovich, J.E.; Medica, P.; Avery, H.; Meyer, K.; Bowser, G.; Brown, A.

1999-01-01

The stability of any population is a function of how many young are produced and how many survive to reproduce. Populations with low reproductive output and high mortality will decline until such time as deaths and births are at least balanced. Monitoring populations of sensitive species is particularly important to ensure that conditions do not favor decline or extinction. Turtles, including tortoises, are characterized by life history traits that make them slow to adapt to rapid changes in mortality and habitat alteration. Long life spans (in excess of 50 years), late maturity, and widely variable nest success are traits that allowed turtles to outlive the dinosaurs, but they are poorly adapted for life in the rapidly changing modern world. Increased mortality of young and adults can seriously tip the delicate balance required for turtles to survive.

Antioxidant Capacity of “Mexican Arnica” Heterotheca inuloides Cass Natural Products and Some Derivatives: Their Anti-Inflammatory Evaluation and Effect on C. elegans Life Span

PubMed Central

Rodríguez-Chávez, José Luis; Nieto-Camacho, Antonio; Delgado-Lamas, Guillermo

2015-01-01

It has been suggested that the accumulation of biomolecular damage caused by reactive oxygen species (ROS) contributes to aging. The antioxidant activity is related to the ability of certain compounds to protect against the potentially harmful effect of processes or reactions involving ROS. This ability is associated with the termination of free radical propagation in biological systems. From Heterotheca inuloides various compounds which have shown to possess antioxidant capacity and scavenging ROS. The aim of this study was to determine the antioxidant capacity of additional natural components isolated from H. inuloides and some semisynthetic derivatives, their anti-inflammatory activity and the effect on Caenorhabditis elegans nematode life span. Compounds showed ability to inhibit various biological processes such as lipid peroxidation, scavenge nonbiological important oxidants such as 1O2, OH∙, H2O2, and HOCl and scavenge non biological stable free radicals (DPPH). Some cadinane type compounds showed possess antioxidant, ROS scavenging capacity, anti-inflammatory activity, and effect on the C. elegans life span. Flavonoid type compounds increased the life of the nematode and quercetin was identified as the compound with the greatest activity. The modification of chemical structure led to a change in the antioxidant capacity, the anti-inflammatory activity, and the survival of the worm. PMID:25821555

Life-History Traits of the Model Organism Pristionchus pacificus Recorded Using the Hanging Drop Method: Comparison with Caenorhabditis elegans.

PubMed

Gilarte, Patricia; Kreuzinger-Janik, Bianca; Majdi, Nabil; Traunspurger, Walter

2015-01-01

The nematode Pristionchus pacificus is of growing interest as a model organism in evolutionary biology. However, despite multiple studies of its genetics, developmental cues, and ecology, the basic life-history traits (LHTs) of P. pacificus remain unknown. In this study, we used the hanging drop method to follow P. pacificus at the individual level and thereby quantify its LHTs. This approach allowed direct comparisons with the LHTs of Caenorhabditis elegans recently determined using this method. When provided with 5×10(9) Escherichia coli cells ml(-1) at 20°C, the intrinsic rate of natural increase of P. pacificus was 1.125 (individually, per day); mean net production was 115 juveniles produced during the life-time of each individual, and each nematode laid an average of 270 eggs (both fertile and unfertile). The mean age of P. pacificus individuals at first reproduction was 65 h, and the average life span was 22 days. The life cycle of P. pacificus is therefore slightly longer than that of C. elegans, with a longer average life span and hatching time and the production of fewer progeny.

Gender norms as health harms: reclaiming a life course perspective on sexual and reproductive health and rights.

PubMed

Crockett, Cailin; Cooper, Bergen

2016-11-01

Despite their demographic significance and the lifetime impact of gender disparities on their health and rights, women considered older than reproductive age are excluded from most investments in global public health. While development policies linking human rights with access to sexual and reproductive healthcare have yielded progress towards improving the status of women and girls, older women have not benefited from these initiatives. Yet as women grow older, they experience a range of health conditions rooted in their reproductive biology - from ageing with fistula, to cervical and breast cancers. Current approaches to global women's health ignore these serious conditions, harming older women through the perpetuation of gender norms that construe women's health through a narrow reproductive lens. Meanwhile, older women are generally absent from global ageing discourse, which lacks a gender perspective, creating a dual invisibility as the field of global women's health presumes ageing women are accounted for. Reclaiming the sexual rights framework suggested by the International Conference on Population and Development and the Beijing Platform for Action, we call for the revision of global health policies to incorporate a life course approach to women's health as a matter of human rights. Published by Elsevier B.V.

Oxidative shielding and the cost of reproduction.

PubMed

Blount, Jonathan D; Vitikainen, Emma I K; Stott, Iain; Cant, Michael A

2016-05-01

Life-history theory assumes that reproduction and lifespan are constrained by trade-offs which prevent their simultaneous increase. Recently, there has been considerable interest in the possibility that this cost of reproduction is mediated by oxidative stress. However, empirical tests of this theory have yielded equivocal support. We carried out a meta-analysis to examine associations between reproduction and oxidative damage across markers and tissues. We show that oxidative damage is positively associated with reproductive effort across females of various species. Yet paradoxically, categorical comparisons of breeders versus non-breeders reveal that transition to the reproductive state is associated with a step-change reduction in oxidative damage in certain tissues and markers. Developing offspring may be particularly sensitive to harm caused by oxidative damage in mothers. Therefore, such reductions could potentially function to shield reproducing mothers, gametes and developing offspring from oxidative insults that inevitably increase as a consequence of reproductive effort. According to this perspective, we hypothesise that the cost of reproduction is mediated by dual impacts of maternally-derived oxidative damage on mothers and offspring, and that mothers may be selected to diminish such damage. Such oxidative shielding may explain why many existing studies have concluded that reproduction has little or no oxidative cost. Future advance in life-history theory therefore needs to take account of potential transgenerational impacts of the mechanisms underlying life-history trade-offs. © 2015 Cambridge Philosophical Society.

Mice selectively bred for open-field thigmotaxis: life span and stability of the selection trait.

PubMed

Leppänen, Pia K; Ewalds-Kvist, S Béatrice M; Selander, Ritva-Kajsa

2005-04-01

In 2 experiments, the authors examined 69 mice selectively bred for high or low levels of open-field (OF) thigmotactic behavior (high open-field thigmotaxis [HOFT] and low open-field thigmotaxis [LOFT], respectively). They found that the strains differed in defecation during the 60-min exposure to the OF. Furthermore, the strains differed with regard to their life spans: The more thigmotactic HOFT mice lived longer than the LOFT mice. The strains were not differentiated by food intake or excretion. The strain difference in thigmotaxis was not age dependent, and it persisted in the home-cage condition as well. Neither the location (center or wall) of the starting point nor the shape (circular or square) of the OF arena affected the difference in wall-seeking behavior between the two strains. The authors concluded that the difference in thigmotaxis (or emotionality) between the HOFT and LOFT mice is a stable and robust feature of these animals.

Reproductive cycles of deer.

PubMed

Asher, G W

2011-04-01

The cervids are a complex assemblage of taxa showing extreme diversity in morphology, physiology, ecology and geographical distribution. Reproductive strategies adopted by various species are also diverse, and include a range from highly seasonal to completely aseasonal birth patterns. The recent growth in knowledge on cervid reproduction is strongly biased towards the larger-bodied, gregarious mixed grazer-browser species that have adapted well to human management and commercialisation. These species tend to represent 'K-selected' climax species characterised by very productive annual breeding success, singleton births and long breeding life (10+ years). Conversely, we know relatively little about the reproductive patterns of the 'r-selected' smaller-bodied, solitary (and often highly territorial), forest-dwelling browser species, often characterised by great fecundity (twinning) and shorter breeding life (<10 years). This group includes many of the endangered cervid taxa. This review extends earlier reviews to include more recent work on cervid reproductive cycles, particularly in relation to environmental factors influencing gestation length. Copyright © 2010 Elsevier B.V. All rights reserved.

General Slowing and Education Mediate Task Switching Performance Across the Life-Span

PubMed Central

Moretti, Luca; Semenza, Carlo; Vallesi, Antonino

2018-01-01

Objective: This study considered the potential role of both protective factors (cognitive reserve, CR) and adverse ones (general slowing) in modulating cognitive flexibility in the adult life-span. Method: Ninety-eight individuals performed a task-switching (TS) paradigm in which we adopted a manipulation concerning the timing between the cue and the target. Working memory demands were minimized by using transparent cues. Additionally, indices of cognitive integrity, depression, processing speed and different CR dimensions were collected and used in linear models accounting for TS performance under the different time constraints. Results: The main results showed similar mixing costs and higher switching costs in older adults, with an overall age-dependent effect of general slowing on these costs. The link between processing speed and TS performance was attenuated when participants had more time to prepare. Among the different CR indices, formal education only was associated with reduced switch costs under time pressure. Discussion: Even though CR is often operationalized as a unitary construct, the present research confirms the benefits of using tools designed to distinguish between different CR dimensions. Furthermore, our results provide empirical support to the assumption that processing speed influence on executive performance depends on time constraints. Finally, it is suggested that whether age differences appear in terms of switch or mixing costs depends on working memory demands (which were low in our tasks with transparent cues). PMID:29780341

Eyewitness identification across the life span: A meta-analysis of age differences.

PubMed

Fitzgerald, Ryan J; Price, Heather L

2015-11-01

Lineup identifications are often a critical component of criminal investigations. Over the past 35 years, researchers have been conducting empirical studies to assess the impact of witness age on identification accuracy. A previous meta-analysis indicated that children are less likely than adults to correctly reject a lineup that does not contain the culprit, but children 5 years and older are as likely as adults to make a correct identification if the culprit is in the lineup (Pozzulo & Lindsay, 1998). We report an updated meta-analysis of age differences in eyewitness identification, summarizing data from 20,244 participants across 91 studies. Contrary to extant reviews, we adopt a life span approach and examine witnesses from early childhood to late adulthood. Children's increased tendency to erroneously select a culprit-absent lineup member was replicated. Children were also less likely than young adults to correctly identify the culprit. Group data from culprit-absent and culprit-present lineups were used to produce signal detection measures, which indicated young adults were better able than children to discriminate between guilty and innocent suspects. A strikingly similar pattern emerged for older adults, who had even stronger deficits in discriminability than children, relative to adults. Although identifications by young adults were the most reliable, identifications by all witnesses had probative value. (c) 2015 APA, all rights reserved).

Reproductive cessation and post-reproductive lifespan in Asian elephants and pre-industrial humans

PubMed Central

2014-01-01

Introduction Short post-reproductive lifespan is widespread across species, but prolonged post-reproductive life-stages of potential adaptive significance have been reported only in few mammals with extreme longevity. Long post-reproductive lifespan contradicts classical evolutionary predictions of simultaneous senescence in survival and reproduction, and raises the question of whether extreme longevity in mammals promotes such a life-history. Among terrestrial mammals, elephants share the features with great apes and humans, of having long lifespan and offspring with long dependency. However, little data exists on the frequency of post-reproductive lifespan in elephants. Here we use extensive demographic records on semi-captive Asian elephants (n = 1040) and genealogical data on pre-industrial women (n = 5336) to provide the first comparisons of age-specific reproduction, survival and post-reproductive lifespan in both of these long-lived species. Results We found that fertility decreased after age 50 in elephants, but the pattern differed from a total loss of fertility in menopausal women with many elephants continuing to reproduce at least until the age of 65 years. The probability of entering a non-reproductive state increased steadily in elephants from the earliest age of reproduction until age 65, with the longer living elephants continuing to reproduce until older ages, in contrast to humans whose termination probability increased rapidly after age 35 and reached 1 at 56 years, but did not depend on longevity. Post-reproductive lifespan reached 11–17 years in elephants and 26–27 years in humans living until old age (depending on method), but whereas half of human adult lifespan (of those reproductive females surviving to the age of 5% fecundity) was spent as post-reproductive, only one eighth was in elephants. Consequently, although some elephants have long post-reproductive lifespans, relatively few individuals reach such a phase and the

Early reproductive maturity among Pumé foragers: Implications of a pooled energy model to fast life histories.

PubMed

Kramer, Karen L; Greaves, Russell D; Ellison, Peter T

2009-01-01

Life history theory places central importance on relationships between ontogeny, reproduction, and mortality. Fast human life histories have been theoretically and empirically associated with high mortality regimes. This relationship, however, poses an unanswered question about energy allocation. In epidemiologically stressful environments, a greater proportion of energy is allocated to immune function. If growth and maintenance are competing energetic expenditures, less energy should be available for growth, and the mechanism to sustain rapid maturation remains unclear. The human pattern of extended juvenile provisioning and resource sharing may provide an important source of variation in energy availability not predicted by tradeoff models that assume independence at weaning. We consider a group of South American foragers to evaluate the effects that pooled energy budgets may have on early reproduction. Despite growing up in an environment with distinct seasonal under-nutrition, harsh epidemiological conditions, and no health care, Pumé girls mature quickly and initiate childbearing in their midteens. Pooled energy budgets compensate for the low productivity of girls not only through direct food transfers but importantly by reducing energy they would otherwise expend in foraging activities to meet metabolic requirements. We suggest that pooled energy budgets affect energy availability at both extrinsic and intrinsic levels. Because energy budgets are pooled, Pumé girls and young women are buffered from environmental downturns and can maximize energy allocated to growth completion and initiate reproduction earlier than a traditional bound-energy model would predict. 2009 Wiley-Liss, Inc.

Gene-environment interaction and male reproductive function

PubMed Central

Axelsson, Jonatan; Bonde, Jens Peter; Giwercman, Yvonne L.; Rylander, Lars; Giwercman, Aleksander

2010-01-01

As genetic factors can hardly explain the changes taking place during short time spans, environmental and lifestyle-related factors have been suggested as the causes of time-related deterioration of male reproductive function. However, considering the strong heterogeneity of male fecundity between and within populations, genetic variants might be important determinants of the individual susceptibility to the adverse effects of environment or lifestyle. Although the possible mechanisms of such interplay in relation to the reproductive system are largely unknown, some recent studies have indicated that specific genotypes may confer a larger risk of male reproductive disorders following certain exposures. This paper presents a critical review of animal and human evidence on how genes may modify environmental effects on male reproductive function. Some examples have been found that support this mechanism, but the number of studies is still limited. This type of interaction studies may improve our understanding of normal physiology and help us to identify the risk factors to male reproductive malfunction. We also shortly discuss other aspects of gene-environment interaction specifically associated with the issue of reproduction, namely environmental and lifestyle factors as the cause of sperm DNA damage. It remains to be investigated to what extent such genetic changes, by natural conception or through the use of assisted reproductive techniques, are transmitted to the next generation, thereby causing increased morbidity in the offspring. PMID:20348940

Life Span Studies of ADHD-Conceptual Challenges and Predictors of Persistence and Outcome.

PubMed

Caye, Arthur; Swanson, James; Thapar, Anita; Sibley, Margaret; Arseneault, Louise; Hechtman, Lily; Arnold, L Eugene; Niclasen, Janni; Moffitt, Terrie; Rohde, Luis Augusto

2016-12-01

There is a renewed interest in better conceptualizing trajectories of attention-deficit/hyperactivity disorder (ADHD) from childhood to adulthood, driven by an increased recognition of long-term impairment and potential persistence beyond childhood and adolescence. This review addresses the following major issues relevant to the course of ADHD in light of current evidence from longitudinal studies: (1) conceptual and methodological issues related to measurement of persistence of ADHD, (2) estimates of persistence rate from childhood to adulthood and its predictors, (3) long-term negative outcomes of childhood ADHD and their early predictors, and (4) the recently proposed new adult-onset ADHD. Estimates of persistence vary widely in the literature, and diagnostic criteria, sample characteristics, and information source are the most important factors explaining variability among studies. Evidence indicates that ADHD severity, comorbid conduct disorder and major depressive disorder, and treatment for ADHD are the main predictors of ADHD persistence from childhood to adulthood. Comorbid conduct disorder and ADHD severity in childhood are the most important predictors of adverse outcomes in adulthood among children with ADHD. Three recent population studies suggested the existence of a significant proportion of individuals who report onset of ADHD symptoms and impairments after childhood. Finally, we highlight areas for improvement to increase our understanding of ADHD across the life span.

C-SPAN Networks: Professor's Guide. C-SPAN in the Classroom Series.

ERIC Educational Resources Information Center

C-SPAN, Washington, DC.

This C-SPAN publication is intended to serve as a forum, enabling college-level members of C-SPAN in the classroom program to share ideas regarding programming and classroom academic research. This issue explains the different C-SPAN networks and what their purposes are. The publication contains 12 articles written by professors who use the C-SPAN…

Causes of decreased life expectancy over the life span in bipolar disorder.

PubMed

Kessing, Lars Vedel; Vradi, Eleni; McIntyre, Roger S; Andersen, Per Kragh

2015-07-15

Accelerated aging has been proposed as a mechanism explaining the increased prevalence of comorbid general medical illnesses in bipolar disorder. To test the hypothesis that lost life years due to natural causes starts in early and mid-adulthood, supporting the hypothesis of accelerated aging. Using individual data from nationwide registers of patient with a diagnosis of bipolar disorder we calculated remaining life expectancies before age 90 years for values of age 15, 25, 35…75 years among all individuals alive in year 2000. Further, we estimated the reduction in life expectancy due to natural causes (physical illnesses) and unnatural causes (suicide and accidents) in relation to age. A total of 22,635 patients with bipolar disorder were included in the study in addition to data from the entire Danish general population of 5.4 million people. At age 15 years, remaining life expectancy before age 90 years was decreased 12.7 and 8.9 life years, respectively, for men and women with bipolar disorder. For 15-year old boys with bipolar disorder, natural causes accounted for 58% of all lost life years and for 15-year old girls, natural causes accounted for 67% increasing to 74% and 80% for 45-year old men and women, respectively. Data concern patients who get contact to hospital psychiatry only. Natural causes of death is the most prevalent reason for lost life years already from adolescence and increases substantially during early and mid-adulthood, in this way supporting the hypothesis of accelerated aging. Early intervention in bipolar disorder should not only focus on improving outcome of the bipolar disorder but also on decreasing the risk of comorbid general medical illnesses. Copyright © 2015 Elsevier B.V. All rights reserved.

"Life-span development of visual working memory: When is feature binding difficult?": Correction to Cowan et al. (2006).

PubMed

2016-10-01

Reports an error in "Life-span development of visual working memory: When is feature binding difficult?" by Nelson Cowan, Moshe Naveh-Benjamin, Angela Kilb and J. Scott Saults ( Developmental Psychology , 2006[Nov], Vol 42[6], 1089-1102). In the article, there were two errors in experiment 1a. The mean for color item information in older adults was incorrectly calculated. As a result, Figure 3 shows a mean of over .70. The true mean was .63 ( SEM =.04). This change diminishes the magnitude of the aging deficit for associative information, although this deficit still appears to remain, to a smaller extent. (For a conceptual replication see Peterson & Naveh-Benjamin, 2016). There also was an error in the experimental procedure of Experiment 1a. The older adults in that experiment received only half the number of trials specified in the methods section, and half as much as the other groups. For all groups, when there were 4 or 6 items and the probe was a binding change, the probed location was matched by the same color at 1 other location but, when there were 8 or 10 squares, the probed location was matched by the same color at 1, 2, or 3 other locations. For 8 squares the number of trials was identical for these three trial subtypes whereas, for 10 squares, most of the trials had the same color at just 1 other location. These errors suggest that the experiment should be taken as only preliminary evidence that there is an aging deficit in color-location binding in visual working memory when color and binding trials are mixed in the same trial blocks. (The following abstract of the original article appeared in record 2006-20488-009.) We asked whether the ability to keep in working memory the binding between a visual object and its spatial location changes with development across the life span more than memory for item information. Paired arrays of colored squares were identical or differed in the color of one square, and in the latter case, the changed color was unique

The Prolonged Life-Span of Alveolar Macrophages

PubMed Central

Murphy, Jaime; Summer, Ross; Wilson, Andrew A.; Kotton, Darrell N.; Fine, Alan

2008-01-01

To further examine the half-life of alveolar macrophages, chimeric CD 45.2 mice were generated through bone marrow transplantation of donor CD 45.1 cells. Before administration of donor cells, recipient mice were divided into two cohorts: the first cohort received total body irradiation; the second cohort also received irradiation—however, the thorax, head, and upper extremities were shielded with lead. Flow cytometric analysis was then performed on blood, peritoneal, and bronchoalveolar lavage cells over time to quantify engraftment. The data generated for the unshielded cohort of mice revealed a macrophage half-life of 30 days. In the shielded cohort, however, we found that by 8 months there was negligible replacement of recipient alveolar macrophages by donor cells, despite reconstitution of the blood and peritoneum by donor bone marrow. Consistent with these findings, the mean fluorescent intensity of alveolar macrophages remained stable over a 4-week period after in vivo PKH26 dye loading. Together, these data show that previous alveolar macrophage half-life studies were confounded by the fact that they did not account for the toxic effects of irradiation conditioning regimens, and demonstrate that the bone marrow does not significantly contribute to the alveolar macrophage compartment during steady-state conditions. PMID:18192503

"Choosing Life": Birth Mothers on Abortion and Reproductive Choice.

PubMed

Sisson, Gretchen

2015-01-01

As the least-chosen option when faced with an unplanned pregnancy, adoption remains largely unexamined as a reproductive choice. Although the anti-abortion movement promotes adoption as its preferred alternative to abortion, little is known of birth mothers' pregnancy decision making and whether adoption was chosen in lieu of abortion. I conducted in-depth interviews with 40 women who had placed infants for adoption from 1962 to 2009. Participants were asked about all aspects of their adoption experiences, including their pregnancy decision making and thoughts on abortion. Interview transcripts were analyzed using grounded theory to find unifying themes speaking to reproductive choice. Participants' stories revealed widely varying ideas about abortion. Many were opposed to abortion, but a greater number supported abortion as a reproductive choice, although one they did not choose for themselves. Birth mothers were most often choosing between adoption and parenting, not adoption and abortion. Most participants would have preferred to parent, but did not because of external variables. Mixed experiences with adoption also influenced participants' long-term ideas about reproductive choice. Findings suggest that the anti-abortion framing of adoption as a preferable alternative to abortion is inconsistent with birth mothers' pregnancy decision-making experiences and their feelings about adoption. Reducing social barriers to both abortion and parenting will ensure that adoption is situated as a true reproductive choice. Copyright © 2015 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Age-related changes in somatic condition and reproduction in the Eurasian beaver: Resource history influences onset of reproductive senescence

PubMed Central

Newman, Chris; Macdonald, David W.

2017-01-01

Using 15 years of data from a stable population of wild Eurasian beavers (Castor fiber), we examine how annual and lifetime access to food resources affect individual age-related changes in reproduction and somatic condition. We found an age-related decline in annual maternal reproductive output, after a peak at age 5–6. Rainfall, an established negative proxy of annual resource availability for beavers, was consistently associated with lower reproductive output for females of all ages. In contrast, breeding territory quality, as a measure of local resource history over reproductive lifetimes, caused differences in individual patterns of reproductive senescence; animals from lower quality territories senesced when younger. Litter size was unrelated to maternal age, although adult body weight increased with age. In terms of resource effects, in poorer years but not in better years, older mothers produced larger offspring than did younger mothers, giving support to the constraint theory. Overall, our findings exemplify state-dependent life-history strategies, supporting an effect of resources on reproductive senescence, where cumulative differences in resource access, and not just reproductive strategy, mediate long-term reproductive trade-offs, consistent with the disposable soma and reproductive restraint theories. We propose that flexible life-history schedules could play a role in the dynamics of populations exhibiting reproductive skew, with earlier breeding opportunities leading to an earlier senescence schedule through resource dependent mechanisms. PMID:29206840

FACTORS AFFECTING REPRODUCTION AND THE IMPORTANCE OF ADULT SIZE ON REPRODUCTIVE OUTPUT OF THE MIDGE, CHIRONOMUS TENTANS

EPA Science Inventory

Incorporating reproductive endpoints into sediment toxicity tests has become an important consideration in ecological risk assessments. The capacity to assess reproduction was one of the primary objectives underlying the recent development of a life-cycle test with the midge, Ch...

Missing doses in the life span study of Japanese atomic bomb survivors.

PubMed

Richardson, David B; Wing, Steve; Cole, Stephen R

2013-03-15

The Life Span Study of atomic bomb survivors is an important source of risk estimates used to inform radiation protection and compensation. Interviews with survivors in the 1950s and 1960s provided information needed to estimate radiation doses for survivors proximal to ground zero. Because of a lack of interview or the complexity of shielding, doses are missing for 7,058 of the 68,119 proximal survivors. Recent analyses excluded people with missing doses, and despite the protracted collection of interview information necessary to estimate some survivors' doses, defined start of follow-up as October 1, 1950, for everyone. We describe the prevalence of missing doses and its association with mortality, distance from hypocenter, city, age, and sex. Missing doses were more common among Nagasaki residents than among Hiroshima residents (prevalence ratio = 2.05; 95% confidence interval: 1.96, 2.14), among people who were closer to ground zero than among those who were far from it, among people who were younger at enrollment than among those who were older, and among males than among females (prevalence ratio = 1.22; 95% confidence interval: 1.17, 1.28). Missing dose was associated with all-cancer and leukemia mortality, particularly during the first years of follow-up (all-cancer rate ratio = 2.16, 95% confidence interval: 1.51, 3.08; and leukemia rate ratio = 4.28, 95% confidence interval: 1.72, 10.67). Accounting for missing dose and late entry should reduce bias in estimated dose-mortality associations.

Deconstructing mammalian reproduction: using knockouts to define fertility pathways.

PubMed

Roy, Angshumoy; Matzuk, Martin M

2006-02-01

Reproduction is the sine qua non for the propagation of species and continuation of life. It is a complex biological process that is regulated by multiple factors during the reproductive life of an organism. Over the past decade, the molecular mechanisms regulating reproduction in mammals have been rapidly unraveled by the study of a vast number of mouse gene knockouts with impaired fertility. The use of reverse genetics to generate null mutants in mice through targeted disruption of specific genes has enabled researchers to identify essential regulators of spermatogenesis and oogenesis in vivo and model human disorders affecting reproduction. This review focuses on the merits, utility, and the variations of the knockout technology in studies of reproduction in mammals.

Effects of kaolin particle films on the life span of an orb-weaver spider.

PubMed

Benhadi-Marín, Jacinto; Pereira, José Alberto; Santos, Sónia A P

2016-02-01

Araniella cucurbitina (Araneae: Araneidae) is a widespread orb-weaver spider commonly found in agroecosystems. Mineral particle films such as kaolin, due to their protective or anti-feeding action, can represent an alternative to pesticides, especially in organic farming systems, but little is known about its effects on A. cucurbitina. Therefore, we tested the effect of kaolin sprays on the life span of A. cucurbitina under laboratory conditions. Four treatments were tested encompassing different exposure routes. Thus, kaolin sprays were applied on (i) the surface, (ii) the prey (fly), (iii) the spider and (iv) both spider & prey. A control group was tested with water in each treatment. Results showed that sprays of kaolin significantly affected the survival of A. curcubitina when applications were done on the surface and on both spider & prey registering a reduction of 48% and 56%, respectively. Spiders in control obtained higher probability of reaching alive at the end of the assay than those treated with kaolin. Differences observed can be explained by the feeding behavior of the species and may depend on the consumption of the web by the spider and the ratio spider/fly for body size. Copyright © 2015 Elsevier Ltd. All rights reserved.

Reducing Unintended Pregnancies Through Web-Based Reproductive Life Planning and Contraceptive Action Planning among Privately Insured Women: Study Protocol for the MyNewOptions Randomized, Controlled Trial.

PubMed

Chuang, Cynthia H; Velott, Diana L; Weisman, Carol S; Sciamanna, Christopher N; Legro, Richard S; Chinchilli, Vernon M; Moos, Merry-K; Francis, Erica B; Confer, Lindsay N; Lehman, Erik B; Armitage, Christopher J

2015-01-01

The Affordable Care Act mandates that most women of reproductive age with private health insurance have full contraceptive coverage with no out-of-pocket costs, creating an actionable time for women to evaluate their contraceptive choices without cost considerations. The MyNewOptions study is a three-arm, randomized, controlled trial testing web-based interventions aimed at assisting privately insured women with making contraceptive choices that are consistent with their reproductive goals. Privately insured women between the ages of 18 and 40 not intending pregnancy were randomly assigned to one of three groups: 1) a reproductive life planning (RLP) intervention, 2) a reproductive life planning enriched with contraceptive action planning (RLP+) intervention, or 3) an information only control group. Both the RLP and RLP+ guide women to identify their individualized reproductive goals and contraceptive method requirements. The RLP+ additionally includes a contraceptive action planning component, which uses if-then scenarios that allow the user to problem solve situations that make it difficult to be adherent to their contraceptive method. All three groups have access to a reproductive options library containing information about their contraceptive coverage and the attributes of alternative contraceptive methods. Women completed a baseline survey with follow-up surveys every 6 months for 2 years concurrent with intervention boosters. Study outcomes include contraceptive use and adherence. ClinicalTrials.gov identifier: NCT02100124. Results from the MyNewOptions study will demonstrate whether web-based reproductive life planning, with or without contraceptive action planning, helps insured women make patient-centered contraceptive choices compared with an information-only control condition. Copyright © 2015 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Personality, immune response and reproductive success: an appraisal of the pace-of-life syndrome hypothesis.

PubMed

Monceau, Karine; Dechaume-Moncharmont, François-Xavier; Moreau, Jérôme; Lucas, Camille; Capoduro, Rémi; Motreuil, Sébastien; Moret, Yannick

2017-07-01

The pace-of-life syndrome (POLS) hypothesis is an extended concept of the life-history theory that includes behavioural traits. The studies challenging the POLS hypothesis often focus on the relationships between a single personality trait and a physiological and/or life-history trait. While pathogens represent a major selective pressure, few studies have been interested in testing relationships between behavioural syndrome, and several fitness components including immunity. The aim of this study was to address this question in the mealworm beetle, Tenebrio molitor, a model species in immunity studies. The personality score was estimated from a multidimensional syndrome based of four repeatable behavioural traits. In a first experiment, we investigated its relationship with two measures of fitness (reproduction and survival) and three components of the innate immunity (haemocyte concentration, and levels of activity of the phenoloxidase including the total proenzyme and the naturally activated one) to challenge the POLS hypothesis in T. molitor. Overall, we found a relationship between behavioural syndrome and reproductive success in this species, thus supporting the POLS hypothesis. We also showed a sex-specific relationship between behavioural syndrome and basal immune parameters. In a second experiment, we tested whether this observed relationship with innate immunity could be confirmed in term of differential survival after challenging by entomopathogenic bacteria, Bacillus thuringiensis. In this case, no significant relationship was evidenced. We recommend that future researchers on the POLS should control for differences in evolutionary trajectory between sexes and to pay attention to the choice of the proxy used, especially when looking at immune traits. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

Childhood self-control and unemployment throughout the life span: evidence from two British cohort studies.

PubMed

Daly, Michael; Delaney, Liam; Egan, Mark; Baumeister, Roy F

2015-06-01

The capacity for self-control may underlie successful labor-force entry and job retention, particularly in times of economic uncertainty. Analyzing unemployment data from two nationally representative British cohorts (N = 16,780), we found that low self-control in childhood was associated with the emergence and persistence of unemployment across four decades. On average, a 1-SD increase in self-control was associated with a reduction in the probability of unemployment of 1.4 percentage points after adjustment for intelligence, social class, and gender. From labor-market entry to middle age, individuals with low self-control experienced 1.6 times as many months of unemployment as those with high self-control. Analysis of monthly unemployment data before and during the 1980s recession showed that individuals with low self-control experienced the greatest increases in unemployment during the recession. Our results underscore the critical role of self-control in shaping life-span trajectories of occupational success and in affecting how macroeconomic conditions affect unemployment levels in the population. © The Author(s) 2015.

Life Satisfaction, Self-Esteem, and Subjective Age in Women across the Life Span

ERIC Educational Resources Information Center

Borzumato-Gainey, Christine; Kennedy, Alison; McCabe, Beth; Degges-White, Suzanne

2009-01-01

A study of 320 women, ages 21 to 69, explored the relations among relationship status, subjective age, self-esteem, and life satisfaction. Women in married or partnered relationships had higher levels of life satisfaction than did single women. Women in their 30s and 40s had significantly lower levels of life satisfaction than did other age…

Gender issues in reproductive health: a review.

PubMed

Adinma, Echendu D; Adinma, Brian-D J I

2011-01-01

Gender, for its impact on virtually every contemporary life issue, can rightly be regarded as a foremost component of reproductive health. Reproductive health basically emphasises on people and their rights to sexuality, reproduction, and family planning, and the information to actualize these right, which has been inextricably linked to development at the International Conference on Population and Development (ICPD) held in Cairo, Egypt, in 1994. Women's sexual and reproductive rights became recognised as universal human right, violations of which occur in some reproductive health areas including gender concerns. Gender inequality and inequity encompass gender based violence as well as gender discrimination which cuts across the life cycle of the woman; attitudes, religious and cultural practices of various nations; and issues related to employment, economy, politics, and development. The redress of gender inequality is a collective responsibility of nations and supranational agencies. Nations should adopt a framework hinged on three pedestals--legal, institutional and policy, employing the three recommended approaches of equal treatment, positive action, and gender mainstreaming.

Span of control matters.

PubMed

Cathcart, Deb; Jeska, Susan; Karnas, Joan; Miller, Sue E; Pechacek, Judy; Rheault, Lolita

2004-09-01

Prompted by manager concerns about span of control, a large, integrated health system set out to determine if span of control really mattered. Was there something to it, or was it just an excuse for poor performance? A team of middle managers studied the problem and ultimately demonstrated a strong relationship between span of control and employee engagement. Consequently, it was decided to add 4 management positions to note the effect. One year later, positive changes were observed in employee engagement scores in all 4 areas. This study suggests careful review of manager spans of control to address the untoward effects of large spans of control on employee engagement.

A 'slow pace of life' in Australian old-endemic passerine birds is not accompanied by low basal metabolic rates.

PubMed

Bech, Claus; Chappell, Mark A; Astheimer, Lee B; Londoño, Gustavo A; Buttemer, William A

2016-05-01

Life history theory suggests that species experiencing high extrinsic mortality rates allocate more resources toward reproduction relative to self-maintenance and reach maturity earlier ('fast pace of life') than those having greater life expectancy and reproducing at a lower rate ('slow pace of life'). Among birds, many studies have shown that tropical species have a slower pace of life than temperate-breeding species. The pace of life has been hypothesized to affect metabolism and, as predicted, tropical birds have lower basal metabolic rates (BMR) than temperate-breeding birds. However, many temperate-breeding Australian passerines belong to lineages that evolved in Australia and share 'slow' life-history traits that are typical of tropical birds. We obtained BMR from 30 of these 'old-endemics' and ten sympatric species of more recently arrived passerine lineages (derived from Afro-Asian origins or introduced by Europeans) with 'faster' life histories. The BMR of 'slow' temperate-breeding old-endemics was indistinguishable from that of new-arrivals and was not lower than the BMR of 'fast' temperate-breeding non-Australian passerines. Old-endemics had substantially smaller clutches and longer maximal life spans in the wild than new arrivals, but neither clutch size nor maximum life span was correlated with BMR. Our results suggest that low BMR in tropical birds is not functionally linked to their 'slow pace of life' and instead may be a consequence of differences in annual thermal conditions experienced by tropical versus temperate species.

Angiotensin Converting Enzyme (ACE) Inhibitor Extends Caenorhabditis elegans Life Span

PubMed Central

Kumar, Sandeep; Dietrich, Nicholas; Kornfeld, Kerry

2016-01-01

Animal aging is characterized by progressive, degenerative changes in many organ systems. Because age-related degeneration is a major contributor to disability and death in humans, treatments that delay age-related degeneration are desirable. However, no drugs that delay normal human aging are currently available. To identify drugs that delay age-related degeneration, we used the powerful Caenorhabdtitis elegans model system to screen for FDA-approved drugs that can extend the adult lifespan of worms. Here we show that captopril extended mean lifespan. Captopril is an angiotensin-converting enzyme (ACE) inhibitor used to treat high blood pressure in humans. To explore the mechanism of captopril, we analyzed the acn-1 gene that encodes the C. elegans homolog of ACE. Reducing the activity of acn-1 extended the mean life span. Furthermore, reducing the activity of acn-1 delayed age-related degenerative changes and increased stress resistance, indicating that acn-1 influences aging. Captopril could not further extend the lifespan of animals with reduced acn-1, suggesting they function in the same pathway; we propose that captopril inhibits acn-1 to extend lifespan. To define the relationship with previously characterized longevity pathways, we analyzed mutant animals. The lifespan extension caused by reducing the activity of acn-1 was additive with caloric restriction and mitochondrial insufficiency, and did not require sir-2.1, hsf-1 or rict-1, suggesting that acn-1 functions by a distinct mechanism. The interactions with the insulin/IGF-1 pathway were complex, since the lifespan extensions caused by captopril and reducing acn-1 activity were additive with daf-2 and age-1 but required daf-16. Captopril treatment and reducing acn-1 activity caused similar effects in a wide range of genetic backgrounds, consistent with the model that they act by the same mechanism. These results identify a new drug and a new gene that can extend the lifespan of worms and suggest new

Reproduction and Breast Cancer Risk

PubMed Central

Hanf, Volker; Hanf, Dorothea

2014-01-01

Summary Reproduction is doubtlessly one of the main biological meanings of life. It is therefore not surprising that various aspects of reproduction impact on breast cancer risk. Various developmental levels may become targets of breast tumorigenesis. This review follows the chronologic sequence of events in the life of a female at risk, starting with the intrauterine development. Furthermore, the influence of both contraceptive measures and fertility treatment on breast cancer development is dealt with, as well as various pregnancy-associated factors, events, and perinatal outcomes. Finally, the contribution of breast feeding to a reduced breast cancer risk is discussed. PMID:25759622

Life Span Studies of ADHD—Conceptual Challenges and Predictors of Persistence and Outcome

PubMed Central

Caye, Arthur; Swanson, James; Thapar, Anita; Sibley, Margaret; Arseneault, Louise; Hechtman, Lily; Arnold, L. Eugene; Niclasen, Janni; Moffitt, Terrie

2018-01-01

There is a renewed interest in better conceptualizing trajectories of attention-deficit/hyperactivity disorder (ADHD) from childhood to adulthood, driven by an increased recognition of long-term impairment and potential persistence beyond childhood and adolescence. This review addresses the following major issues relevant to the course of ADHD in light of current evidence from longitudinal studies: (1) conceptual and methodological issues related to measurement of persistence of ADHD, (2) estimates of persistence rate from childhood to adulthood and its predictors, (3) long-term negative outcomes of childhood ADHD and their early predictors, and (4) the recently proposed new adult-onset ADHD. Estimates of persistence vary widely in the literature, and diagnostic criteria, sample characteristics, and information source are the most important factors explaining variability among studies. Evidence indicates that ADHD severity, comorbid conduct disorder and major depressive disorder, and treatment for ADHD are the main predictors of ADHD persistence from childhood to adulthood. Comorbid conduct disorder and ADHD severity in childhood are the most important predictors of adverse outcomes in adulthood among children with ADHD. Three recent population studies suggested the existence of a significant proportion of individuals who report onset of ADHD symptoms and impairments after childhood. Finally, we highlight areas for improvement to increase our understanding of ADHD across the life span. PMID:27783340

Functional linkages for the pace of life, life-history, and environment in birds.

PubMed

Williams, Joseph B; Miller, Richard A; Harper, James M; Wiersma, Popko

2010-11-01

For vertebrates, body mass underlies much of the variation in metabolism, but among animals of the same body mass, metabolism varies six-fold. Understanding how natural selection can influence variation in metabolism remains a central focus of Physiological Ecologists. Life-history theory postulates that many physiological traits, such as metabolism, may be understood in terms of key maturational and reproductive characteristics over an organism's life-span. Although it is widely acknowledged that physiological processes serve as a foundation for life-history trade-offs, the physiological mechanisms that underlie the diversification of life-histories remain elusive. Data show that tropical birds have a reduced basal metabolism (BMR), field metabolic rate, and peak metabolic rate compared with temperate counterparts, results consistent with the idea that a low mortality, and therefore increased longevity, and low productivity is associated with low mass-specific metabolic rate. Mass-adjusted BMR of tropical and temperate birds was associated with survival rate, in accordance with the view that animals with a slow pace of life tend to have increased life spans. To understand the mechanisms responsible for a reduced rate of metabolism in tropical birds compared with temperate species, we summarized an unpublished study, based on data from the literature, on organ masses for both groups. Tropical birds had smaller hearts, kidneys, livers, and pectoral muscles than did temperate species of the same body size, but they had a relatively larger skeletal mass. Direct measurements of organ masses for tropical and temperate birds showed that the heart, kidneys, and lungs were significantly smaller in tropical birds, although sample sizes were small. Also from an ongoing study, we summarized results to date on connections between whole-organism metabolism in tropical and temperate birds and attributes of their dermal fibroblasts grown in cell culture. Cells derived from

Pretreatment fertility counseling and fertility preservation improve quality of life in reproductive age women with cancer.

PubMed

Letourneau, Joseph M; Ebbel, Erin E; Katz, Patricia P; Katz, Audra; Ai, Wei Z; Chien, A Jo; Melisko, Michelle E; Cedars, Marcelle I; Rosen, Mitchell P

2012-03-15

The post-treatment quality of life (QOL) impacts of receiving precancer-treatment infertility counseling and of pursuing fertility preservation have not been described in large-scale studies of reproductive age women with cancer. In total, 1041 women who were diagnosed between ages 18 and 40 years responded to a retrospective survey and reported whether they received infertility counseling before cancer treatment and whether they took action to preserve fertility. Five cancer types were included: leukemia, Hodgkin disease, non-Hodgkin lymphoma, breast cancer, and gastrointestinal cancer. Validated QOL scales were used: the Decision Regret Score, the Satisfaction with Life Scale (SWLS), and the brief World Health Organization QOL questionnaire. Overall, 560 women (61%) who received treatment that potentially could affect fertility were counseled by the oncology team, 45 (5%) were counseled by fertility specialists, and 36 (4%) took action to preserve fertility. Pretreatment infertility counseling by a fertility specialist and an oncologist resulted in lower regret than counseling by an oncologist alone (8.4 vs 11.0; P < .0001). The addition of fertility preservation (6.6 vs 11.0; P < .0001) also was associated with even lower regret scores than counseling by an oncologist alone. Further improvements also were observed in SWLS scores with the addition of fertility specialist counseling (23.0 vs 19.8; P = .09) or preserving fertility (24.0 vs 19.0; P = .05). Receiving specialized counseling about reproductive loss and pursuing fertility preservation is associated with less regret and greater QOL for survivors, yet few patients are exposed to this potential benefit. Women of reproductive age should have expert counseling and should be given the opportunity to make active decisions about preserving fertility. Copyright © 2011 American Cancer Society.

Alternative life cycle strategies in the West African reed frog Hyperolius nitidulus: the answer to an unpredictable environment?

PubMed

Lampert, Kathrin P; Linsenmair, Eduard K

2002-02-01

The West African reed frog Hyperolius nitidulus, mainly known for its extraordinary aestivation behaviour and physiology, is able to vary its reproductive strategy in response to environmental conditions. We found indirect as well as direct evidence for individuals not following the generally assumed one year-one generation life cycle including an extended aestivation phase during the dry season, but leading very short lives for only a part of that rainy season in which the frogs were born. Second-generation frogs (males and females that reproduced in the season in which they were born) were significantly smaller than all other adults and their egg diameter was reduced. As the pattern and amount of rainfall and thus the span of time suitable for reproduction in H. nitidulus varies strongly between years in this savannah region, a flexible reproductive strategy may be highly adaptive for risk spreading. Alternative reproduction strategies probably contribute to the great success of H. nitidulus in terms of the extension of its geographical range and its often very high local abundance.

Midwives' adoption of the reproductive life plan in contraceptive counselling: a mixed methods study

PubMed Central

Stern, J.; Bodin, M.; Grandahl, M.; Segeblad, B.; Axén, L.; Larsson, M.; Tydén, T.

2015-01-01

STUDY QUESTION How is the reproductive life plan (RLP) adopted in midwifery contraceptive counselling? SUMMARY ANSWER A majority of midwives adopted the RLP in their counselling, had predominantly positive experiences and considered it a feasible tool for promoting reproductive health. WHAT IS KNOWN ALREADY The RLP is a health-promoting tool recommended by the Centers for Disease Control and Prevention in the USA for improving preconception health. It was recently used in a clinical setting in Sweden and was found to increase women's knowledge about fertility and to influence women's wishes to have their last child earlier in life. STUDY DESIGN, SIZE, DURATION An exploratory mixed methods study among 68 midwives who provided contraceptive counselling in primary health care to at least 20 women each during the study period. Midwives received an introduction and materials for using the RLP in contraceptive counselling. Three months later, in the spring of 2014, they were invited to complete a questionnaire and participate in a focus group interview about their adoption of the RLP. PARTICIPANTS/MATERIALS, SETTING, METHODS Data collection was through a questionnaire (n = 53 out of 68; participation rate 78%) and five focus group interviews (n = 22). Participants included both younger and older midwives with longer and shorter experiences of contraceptive counselling in public and private health care in one Swedish county. Quantitative data were analysed for differences between users and non-users, and qualitative data were analysed by qualitative content analysis to explore the midwives experiences and opinions of using the RLP. MAIN RESULTS AND THE ROLE OF CHANCE Sixty-eight per cent of midwives had used the RLP in their contraceptive counselling. Four categories emerged through the focus group interviews: (i) A predominantly positive experience; (ii) The RLP—a health-promoting tool; (iii) individual and societal factors influence the RLP counselling; and (4) long

The influence of sensorimotor experience on the aesthetic evaluation of dance across the life span.

PubMed

Kirsch, Louise P; Cross, Emily S

2018-01-01

Understanding how action perception, embodiment, and emotion interact is essential for advancing knowledge about how we perceive and interact with each other in a social world. One tool that has proved particularly useful in the past decade for exploring the relationship between perception, action, and affect is dance. Dance is, in its essence, a rich and multisensory art form that can be used to help answer not only basic questions about social cognition but also questions concerning how aging shapes the relationship between action perception, and the role played by affect, emotion, and aesthetics in social perception. In the present study, we used a 1-week physical and visual dance training paradigm to instill varying degrees of sensorimotor experience among non-dancers from three distinct age groups (early adolescents, young adults, and older adults). Our aim was to begin to build an understanding of how aging influences the relationship between action embodiment and affective (or aesthetic) value, at both brain and behavioral levels. On balance, our results point toward a similar positive effect of sensorimotor training on aesthetic evaluations across the life span on a behavioral level, but to rather different neural substrates supporting implicit aesthetic judgment of dance movements at different life stages. Taken together, the present study contributes valuable first insights into the relationship between sensorimotor experience and affective evaluations across ages, and underscores the utility of dance as a stimulus and training intervention for addressing key questions relevant to human neuroscience as well as the arts and humanities. © 2018 Elsevier B.V. All rights reserved.

A Perspective on the Importance of Reproductive Mode in Astrobiology

NASA Astrophysics Data System (ADS)

Van Doninck, Karine; Schön, Isa; Martens, Koen

2003-12-01

Reproduction is a vital characteristic of life, and sex is the most common reproductive mode in the eukaryotic world. Sex and reproduction are not necessarily linked mechanisms: Sexuality without reproduction exists, while several forms of asexual reproduction are known. The occurrence of sexuality itself is paradoxical, as it is very costly in evolutionary terms. Most of the hypotheses (more than 20) attempting to explain the prevalence of sex fall into two categories: Sex either creates good gene combinations for adaptation to environments or eliminates bad gene combinations counteracting the accumulation of mutations. In spite of this apparent wealth of beneficial effects of sex, asexuality is not rare. Most eukaryotic, asexual lineages are short-lived and can only persist through the presence of sexual roots, but at least two animal groups, bdelloid rotifers and darwinulid ostracods, seem to claim the status of ancient asexuals. Research on (a)sexuality is relevant to astrobiology in a number of ways. First, strong relationships between the origin and persistence of life in extreme environments and reproductive mode are known. Second, the "habitability" of nonterrestrial environments to life greatly depends on reproductive mode. Whereas asexuals can do equally well or better in harsh environments, they fail to adapt fast enough to changing abiotic and biotic environments. Third, it has been shown that plants reproduce mainly asexually in space, and sperm production and motility in some vertebrates are hampered. Both findings indicate that extraterrestrial life under conditions different from Earth might be dominated by asexual reproduction. Finally, for exchange of biological material between planets, the choice of reproductive mode will be important.

Age-Related Cognitive Effects of Videogame Playing Across the Adult Life span.

PubMed

Wang, Ping; Zhu, Xing-Ting; Liu, Han-Hui; Zhang, Yi-Wen; Hu, Yang; Li, Hui-Jie; Zuo, Xi-Nian

2017-08-01

Previous studies found positive influences of videogame playing on cognition. However, the age-related and task-related effects of videogame experience across the adult life span are still unknown. The current study aimed to systematically investigate this question. The current study used the cross-sectional approach. A total of 166 participants (84 videogame players [VGPs], 82 nonvideogame players [NVGPs]) at the age of 18-80 in the present study were recruited, including 62 young adults aged from 18 to 34 (35 VGPs, 27 NVGPs), 55 middle-aged adults aged between 35 and 59 (24 VGPs, 31 NVGPs), and 49 older adults aged between 60 and 80 (25 VGPs, 24 NVGPs). 1,2 A series of neuropsychological tests from different cognitive domains, including processing speed, visuospatial, attention, memory, and executive function, were conducted on participants. The age-related effects demonstrated that young and older adults benefited more from videogame experience than middle-aged adults. The task-related effects showed that VGPs benefited more from videogame experience in processing speed and visuospatial processing; next was executive function and attention, while no benefits in memory. The effect sizes suggested that the difference in extent between VGPs and NVGPs in processing speed and visuospatial processing is moderate, in attention and executive function is small, and in memory is negligible. The current findings support the beneficial effects and transfer effects of videogame experience; however, the effects presented age-specific and task-specific characteristics. The results provide useful insights for future videogame intervention studies for healthy adults of different ages.

Missing Doses in the Life Span Study of Japanese Atomic Bomb Survivors

PubMed Central

Richardson, David B.; Wing, Steve; Cole, Stephen R.

2013-01-01

The Life Span Study of atomic bomb survivors is an important source of risk estimates used to inform radiation protection and compensation. Interviews with survivors in the 1950s and 1960s provided information needed to estimate radiation doses for survivors proximal to ground zero. Because of a lack of interview or the complexity of shielding, doses are missing for 7,058 of the 68,119 proximal survivors. Recent analyses excluded people with missing doses, and despite the protracted collection of interview information necessary to estimate some survivors' doses, defined start of follow-up as October 1, 1950, for everyone. We describe the prevalence of missing doses and its association with mortality, distance from hypocenter, city, age, and sex. Missing doses were more common among Nagasaki residents than among Hiroshima residents (prevalence ratio = 2.05; 95% confidence interval: 1.96, 2.14), among people who were closer to ground zero than among those who were far from it, among people who were younger at enrollment than among those who were older, and among males than among females (prevalence ratio = 1.22; 95% confidence interval: 1.17, 1.28). Missing dose was associated with all-cancer and leukemia mortality, particularly during the first years of follow-up (all-cancer rate ratio = 2.16, 95% confidence interval: 1.51, 3.08; and leukemia rate ratio = 4.28, 95% confidence interval: 1.72, 10.67). Accounting for missing dose and late entry should reduce bias in estimated dose-mortality associations. PMID:23429722

Pre-treatment fertility counseling and fertility preservation improve quality of life in reproductive age women with cancer

PubMed Central

Letourneau, Joseph M; Ebbel, Erin E; Katz, Patricia P; Katz, Audra; Ai, Wei Z; Chien, A Jo; Melisko, Michelle E; Cedars, Marcelle I; Rosen, Mitchell P

2011-01-01

Background The post-treatment quality of life (QOL) impacts of receiving pre-cancer-treatment infertility counseling and of pursuing fertility preservation have not been described in large-scale studies of reproductive age women with cancer. Methods 1041 women diagnosed between the ages of 18 and 40 responded to a retrospective survey and reported whether they received infertility counseling before cancer treatment and whether they took action to preserve fertility. Five cancer types were included: leukemia, Hodgkin’s disease, non-Hodgkin lymphoma, breast cancer, and gastrointestinal cancer. Validated QOL scales were used: Decision Regret Score (DRS), Satisfaction with Life Scale (SWLS), and World Health Organization QOL BREF (WHOQOL-BREF). Results 560 women (61%) whose treatment could affect fertility were counseled by the oncology team, 45 (5%) were counseled by fertility specialists, 36 (4%) took action to preserve fertility. Pre-treatment infertility counseling by a fertility specialist and an oncologist resulted in lower regret than counseling by an oncologist alone (8.4 vs. 11.0, P<0.0001). The addition of fertility preservation (6.6 vs. 11.0, P<0.0001) was also associated with even lower regret scores than counseling by an oncologist alone.. Further improvements were similarly seen in SWLS with the addition of fertility specialist counseling (23.0 vs. 19.8, P=0.09) or preserving fertility (24.0 vs. 19.0, P=0.05). Conclusions Receiving specialized counseling about reproductive loss and pursuing fertility preservation is associated with less regret and greater QOL for survivors, yet few patients are exposed to this potential benefit. Reproductive aged women should have expert counseling and be given the opportunity to make active decisions about preserving fertility. PMID:21887678

Variation in probability of first reproduction of Weddell seals.

PubMed

Hadley, Gillian L; Rotella, Jay J; Garrott, Robert A; Nichols, James D

2006-09-01

1. For many species, when to begin reproduction is an important life-history decision that varies by individual and can have substantial implications for lifetime reproductive success and fitness. 2. We estimated age-specific probabilities of first-time breeding and modelled variation in these rates to determine age at first reproduction and understand why it varies in a population of Weddell seals in Erebus Bay, Antarctica. We used multistate mark-recapture modelling methods and encounter histories of 4965 known-age female seals to test predictions about age-related variation in probability of first reproduction and the effects of annual variation, cohort and population density. 3. Mean age at first reproduction in this southerly located study population (7.62 years of age, SD=1.71) was greater than age at first reproduction for a Weddell seal population at a more northerly and typical latitude for breeding Weddell seals (mean=4-5 years of age). This difference suggests that age at first reproduction may be influenced by whether a population inhabits the core or periphery of its range. 4. Age at first reproduction varied from 4 to 14 years, but there was no age by which all seals recruited to the breeding population, suggesting that individual heterogeneity exists among females in this population. 5. In the best model, the probability of breeding for the first time varied by age and year, and the amount of annual variation varied with age (average variance ratio for age-specific rates=4.3%). 6. Our results affirmed the predictions of life-history theory that age at first reproduction in long-lived mammals will be sensitive to environmental variation. In terms of life-history evolution, this variability suggests that Weddell seals display flexibility in age at first reproduction in order to maximize reproductive output under varying environmental conditions. Future analyses will attempt to test predictions regarding relationships between environmental covariates

Variation in probability of first reproduction of Weddell seals

USGS Publications Warehouse

Hadley, G.L.; Rotella, J.J.; Garrott, R.A.; Nichols, J.D.

2006-01-01

Summary 1. For many species, when to begin reproduction is an important life-history decision that varies by individual and can have substantial implications for lifetime reproductive success and fitness. 2. We estimated age-specific probabilities of first-time breeding and modelled variation in these rates to determine age at first reproduction and understand why it varies in a population of Weddell seals in Erebus Bay, Antarctica. We used multistate mark?recapture modelling methods and encounter histories of 4965 known-age female seals to test predictions about age-related variation in probability of first reproduction and the effects of annual variation, cohort and population density. 3. Mean age at first reproduction in this southerly located study population (7.62 years of age, SD =1.71) was greater than age at first reproduction for a Weddell seal population at a more northerly and typical latitude for breeding Weddell seals (mean =4?5 years of age). This difference suggests that age at first reproduction may be influenced by whether a population inhabits the core or periphery of its range. 4. Age at first reproduction varied from 4 to 14 years, but there was no age by which all seals recruited to the breeding population, suggesting that individual heterogeneity exists among females in this population. 5. In the best model, the probability of breeding for the first time varied by age and year, and the amount of annual variation varied with age (average variance ratio for age-specific rates =4.3%). 6. Our results affirmed the predictions of life-history theory that age at first reproduction in long-lived mammals will be sensitive to environmental variation. In terms of life history evolution, this variability suggests that Weddell seals display flexibility in age at first reproduction in order to maximize reproductive output under varying environmental conditions. Future analyses will attempt to test predictions regarding relationships between environmental

Life beyond the eating disorder: education, relationships, and reproduction.

PubMed

Maxwell, Millie; Thornton, Laura M; Root, Tammy L; Pinheiro, Andrea Poyastro; Strober, Michael; Brandt, Harry; Crawford, Steve; Crow, Scott; Fichter, Manfred M; Halmi, Katherine A; Johnson, Craig; Kaplan, Allan S; Keel, Pamela; Klump, Kelly L; LaVia, Maria; Mitchell, James E; Plotnicov, Kathy; Rotondo, Alessandro; Woodside, D Blake; Berrettini, Wade H; Kaye, Walter H; Bulik, Cynthia M

2011-04-01

We investigated the sociodemographic characteristics in women with and without lifetime eating disorders. Participants were from a multisite international study of eating disorders (N = 2,096). Education level, relationship status, and reproductive status were examined across eating disorder subtypes and compared with a healthy control group. Overall, women with eating disorders were less educated than controls, and duration of illness and age of onset were associated with educational attainment. Menstrual status was associated with both relationship and reproductive status, but eating disorder subtypes did not differ significantly from each other or from healthy controls on these dimensions. Differences in educational attainment, relationships, and reproduction do exist in individuals with eating disorders and are differentially associated with various eating disorder symptoms and characteristics. These data could assist in educating patients and family members about long-term consequences of eating disorders. Copyright © 2010 Wiley Periodicals, Inc.

Body reserves mediate trade-offs between life-history traits: new insights from small pelagic fish reproduction.

PubMed

Brosset, Pablo; Lloret, Josep; Muñoz, Marta; Fauvel, Christian; Van Beveren, Elisabeth; Marques, Virginie; Fromentin, Jean-Marc; Ménard, Frédéric; Saraux, Claire

2016-10-01

Limited resources in the environment prevent individuals from simultaneously maximizing all life-history traits, resulting in trade-offs. In particular, the cost of reproduction is well known to negatively affect energy investment in growth and maintenance. Here, we investigated these trade-offs during contrasting periods of high versus low fish size and body condition (before/after 2008) in the Gulf of Lions. Female reproductive allocation and performance in anchovy ( Engraulis encrasicolus ) and sardine ( Sardina pilchardus ) were examined based on morphometric historical data from the 1970s and from 2003 to 2015. Additionally, potential maternal effects on egg quantity and quality were examined in 2014/2015. After 2008, the gonadosomatic index increased for sardine and remained steady for anchovy, while a strong decline in mean length at first maturity indicated earlier maturation for both species. Regarding maternal effects, for both species egg quantity was positively linked to fish size but not to fish lipid reserves, while the egg quality was positively related to lipid reserves. Atresia prevalence and intensity were rather low regardless of fish condition and size. Finally, estimations of total annual numbers of eggs spawned indicated a sharp decrease for sardine since 2008 but a slight increase for anchovy during the last 5 years. This study revealed a biased allocation towards reproduction in small pelagic fish when confronted with a really low body condition. This highlights that fish can maintain high reproductive investment potentially at the cost of other traits which might explain the present disappearance of old and large individuals in the Gulf of Lions.

Body reserves mediate trade-offs between life-history traits: new insights from small pelagic fish reproduction

PubMed Central

Lloret, Josep; Muñoz, Marta; Fauvel, Christian; Van Beveren, Elisabeth; Marques, Virginie; Fromentin, Jean-Marc; Ménard, Frédéric; Saraux, Claire

2016-01-01

Limited resources in the environment prevent individuals from simultaneously maximizing all life-history traits, resulting in trade-offs. In particular, the cost of reproduction is well known to negatively affect energy investment in growth and maintenance. Here, we investigated these trade-offs during contrasting periods of high versus low fish size and body condition (before/after 2008) in the Gulf of Lions. Female reproductive allocation and performance in anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus) were examined based on morphometric historical data from the 1970s and from 2003 to 2015. Additionally, potential maternal effects on egg quantity and quality were examined in 2014/2015. After 2008, the gonadosomatic index increased for sardine and remained steady for anchovy, while a strong decline in mean length at first maturity indicated earlier maturation for both species. Regarding maternal effects, for both species egg quantity was positively linked to fish size but not to fish lipid reserves, while the egg quality was positively related to lipid reserves. Atresia prevalence and intensity were rather low regardless of fish condition and size. Finally, estimations of total annual numbers of eggs spawned indicated a sharp decrease for sardine since 2008 but a slight increase for anchovy during the last 5 years. This study revealed a biased allocation towards reproduction in small pelagic fish when confronted with a really low body condition. This highlights that fish can maintain high reproductive investment potentially at the cost of other traits which might explain the present disappearance of old and large individuals in the Gulf of Lions. PMID:27853538