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Sample records for chronological life span

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

    Directory of Open Access Journals (Sweden)

    Orozco Helena

    2012-08-01

    Full Text Available Abstract 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.

  2. Accumulation of linear mitochondrial DNA fragments in the nucleus shortens the chronological life span of yeast.

    Science.gov (United States)

    Cheng, Xin; Ivessa, Andreas S

    2012-10-01

    Translocation of mitochondrial DNA (mtDNA) fragments to the nucleus and insertion of those fragments into nuclear DNA has been observed in several organisms ranging from yeast to plants and mammals. Disruption of specific nuclear genes by de novo insertions of mtDNA fragments has even been linked to the initiation of several human diseases. Recently, we demonstrated that baker's yeast strains with high rates of mtDNA fragments migrating to the nucleus (yme1-1 mutant) exhibit short chronological life spans (CLS). The yeast CLS is determined by the survival of non-dividing cell populations. Here, we show that lack of the non-homologous-end-joining enzyme DNA ligase IV (DNL4) can rescue the short CLS of the yme1-1 mutant. In fission yeast, DNA ligase IV has been shown to be required for the capture of mtDNA fragments during the repair of double-stranded DNA breaks in nuclear DNA. In further analyses using pulse field gel and 2D gel electrophoresis we demonstrate that linear mtDNA fragments with likely nuclear localization accumulate in the yme1-1 mutant. The accumulation of the linear mtDNA fragments in the yme1-1 mutant is suppressed when Dnl4 is absent. We propose that the linear nuclear mtDNA fragments accelerate the aging process in the yme1-1 mutant cells by possibly affecting nuclear processes including DNA replication, recombination, and repair as well as transcription of nuclear genes. We speculate further that Dnl4 protein has besides its function as a ligase also a role in DNA protection. Dnl4 protein may stabilize the linear mtDNA fragments in the nucleus by binding to their physical ends. In the absence of Dnl4 protein the linear fragments are therefore unprotected and possibly degraded by nuclear nucleases. Copyright © 2012 Elsevier GmbH. All rights reserved.

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

    Science.gov (United States)

    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

  4. Mitochondrial dysfunction increases oxidative stress and decreases chronological life span in fission yeast.

    Directory of Open Access Journals (Sweden)

    Alice Zuin

    Full Text Available BACKGROUND: Oxidative stress is a probable cause of aging and associated diseases. Reactive oxygen species (ROS originate mainly from endogenous sources, namely the mitochondria. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed the effect of aerobic metabolism on oxidative damage in Schizosaccharomyces pombe by global mapping of those genes that are required for growth on both respiratory-proficient media and hydrogen-peroxide-containing fermentable media. Out of a collection of approximately 2700 haploid yeast deletion mutants, 51 were sensitive to both conditions and 19 of these were related to mitochondrial function. Twelve deletion mutants lacked components of the electron transport chain. The growth defects of these mutants can be alleviated by the addition of antioxidants, which points to intrinsic oxidative stress as the origin of the phenotypes observed. These respiration-deficient mutants display elevated steady-state levels of ROS, probably due to enhanced electron leakage from their defective transport chains, which compromises the viability of chronologically-aged cells. CONCLUSION/SIGNIFICANCE: Individual mitochondrial dysfunctions have often been described as the cause of diseases or aging, and our global characterization emphasizes the primacy of oxidative stress in the etiology of such processes.

  5. The Stationary-Phase Cells of Saccharomyces cerevisiae Display Dynamic Actin Filaments Required for Processes Extending Chronological Life Span.

    Science.gov (United States)

    Vasicova, Pavla; Lejskova, Renata; Malcova, Ivana; Hasek, Jiri

    2015-11-01

    Stationary-growth-phase Saccharomyces cerevisiae yeast cultures consist of nondividing cells that undergo chronological aging. For their successful survival, the turnover of proteins and organelles, ensured by autophagy and the activation of mitochondria, is performed. Some of these processes are engaged in by the actin cytoskeleton. In S. cerevisiae stationary-phase cells, F actin has been shown to form static aggregates named actin bodies, subsequently cited to be markers of quiescence. Our in vivo analyses revealed that stationary-phase cultures contain cells with dynamic actin filaments, besides the cells with static actin bodies. The cells with dynamic actin displayed active endocytosis and autophagy and well-developed mitochondrial networks. Even more, stationary-phase cell cultures grown under calorie restriction predominantly contained cells with actin cables, confirming that the presence of actin cables is linked to successful adaptation to stationary phase. Cells with actin bodies were inactive in endocytosis and autophagy and displayed aberrations in mitochondrial networks. Notably, cells of the respiratory activity-deficient cox4Δ strain displayed the same mitochondrial aberrations and actin bodies only. Additionally, our results indicate that mitochondrial dysfunction precedes the formation of actin bodies and the appearance of actin bodies corresponds to decreased cell fitness. We conclude that the F-actin status reflects the extent of damage that arises from exponential growth. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  6. Life Span Developmental Approach

    OpenAIRE

    Ali Eryilmaz

    2011-01-01

    The Life Span Developmental Approach examines development of individuals which occurs from birth to death. Life span developmental approach is a multi-disciplinary approach related with disciplines like psychology, psychiatry, sociology, anthropology and geriatrics that indicates the fact that development is not completed in adulthood, it continues during the life course. Development is a complex process that consists of dying and death. This approach carefully investigates the development of...

  7. Life Span Developmental Approach

    Directory of Open Access Journals (Sweden)

    Ali Eryilmaz

    2011-03-01

    Full Text Available The Life Span Developmental Approach examines development of individuals which occurs from birth to death. Life span developmental approach is a multi-disciplinary approach related with disciplines like psychology, psychiatry, sociology, anthropology and geriatrics that indicates the fact that development is not completed in adulthood, it continues during the life course. Development is a complex process that consists of dying and death. This approach carefully investigates the development of individuals with respect to developmental stages. This developmental approach suggests that scientific disciplines should not explain developmental facts only with age changes. Along with aging, cognitive, biological, and socioemotional development throughout life should also be considered to provide a reasonable and acceptable context, guideposts, and reasonable expectations for the person. There are three important subjects whom life span developmental approach deals with. These are nature vs nurture, continuity vs discontinuity, and change vs stability. Researchers using life span developmental approach gather and produce knowledge on these three most important domains of individual development with their unique scientific methodology.

  8. Chemical genetic screen identifies lithocholic acid as an anti-aging compound that extends yeast chronological life span in a TOR-independent manner, by modulating housekeeping longevity assurance processes.

    Science.gov (United States)

    Goldberg, Alexander A; Richard, Vincent R; Kyryakov, Pavlo; Bourque, Simon D; Beach, Adam; Burstein, Michelle T; Glebov, Anastasia; Koupaki, Olivia; Boukh-Viner, Tatiana; Gregg, Christopher; Juneau, Mylène; English, Ann M; Thomas, David Y; Titorenko, Vladimir I

    2010-07-01

    In chronologically aging yeast, longevity can be extended by administering a caloric restriction (CR) diet or some small molecules. These life-extending interventions target the adaptable target of rapamycin (TOR) and cAMP/protein kinase A (cAMP/PKA) signaling pathways that are under the stringent control of calorie availability. We designed a chemical genetic screen for small molecules that increase the chronological life span of yeast under CR by targeting lipid metabolism and modulating housekeeping longevity pathways that regulate longevity irrespective of the number of available calories. Our screen identifies lithocholic acid (LCA) as one of such molecules. We reveal two mechanisms underlying the life-extending effect of LCA in chronologically aging yeast. One mechanism operates in a calorie availability-independent fashion and involves the LCA-governed modulation of housekeeping longevity assurance pathways that do not overlap with the adaptable TOR and cAMP/PKA pathways. The other mechanism extends yeast longevity under non-CR conditions and consists in LCA-driven unmasking of the previously unknown anti-aging potential of PKA. We provide evidence that LCA modulates housekeeping longevity assurance pathways by suppressing lipid-induced necrosis, attenuating mitochondrial fragmentation, altering oxidation-reduction processes in mitochondria, enhancing resistance to oxidative and thermal stresses, suppressing mitochondria-controlled apoptosis, and enhancing stability of nuclear and mitochondrial DNA.

  9. The Life Span Dwelling

    OpenAIRE

    Hans-Peter Hebensperger-Hüther; Gabriele Franger-Huhle

    2014-01-01

    The paper presents the findings from a survey of 10 different experimental housing projects in Bavaria. In 2005 students of architecture and students of social work at the University of Applied Science in Coburg approached the topic of “Life Span Dwelling” using interdisciplinary research methods. The scope of the research ranges from urban planning concepts to common spaces in the different neighborhoods, documenting user satisfaction with the individual unit and feasibility of rooms offered...

  10. The Cell Wall Protein Ecm33 of Candida albicans is Involved in Chronological Life Span, Morphogenesis, Cell Wall Regeneration, Stress Tolerance, and Host-Cell Interaction.

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    Gil-Bona, Ana; Reales-Calderon, Jose A; Parra-Giraldo, Claudia M; Martinez-Lopez, Raquel; Monteoliva, Lucia; Gil, Concha

    2016-01-01

    Ecm33 is a glycosylphosphatidylinositol-anchored protein in the human pathogen Candida albicans. This protein is known to be involved in fungal cell wall integrity (CWI) and is also critical for normal virulence in the mouse model of hematogenously disseminated candidiasis, but its function remains unknown. In this work, several phenotypic analyses of the C. albicans ecm33/ecm33 mutant (RML2U) were performed. We observed that RML2U displays the inability of protoplast to regenerate the cell wall, activation of the CWI pathway, hypersensitivity to temperature, osmotic and oxidative stresses and a shortened chronological lifespan. During the exponential and stationary culture phases, nuclear and actin staining revealed the possible arrest of the cell cycle in RML2U cells. Interestingly, a "veil growth," never previously described in C. albicans, was serendipitously observed under static stationary cells. The cells that formed this structure were also observed in cornmeal liquid cultures. These cells are giant, round cells, without DNA, and contain large vacuoles, similar to autophagic cells observed in other fungi. Furthermore, RML2U was phagocytozed more than the wild-type strain by macrophages at earlier time points, but the damage caused to the mouse cells was less than with the wild-type strain. Additionally, the percentage of RML2U apoptotic cells after interaction with macrophages was fewer than in the wild-type strain.

  11. The Cell Wall Protein Ecm33 of Candida albicans is Involved in Chronological Life Span, Morphogenesis, Cell Wall Regeneration, Stress Tolerance, and Host–Cell Interaction

    Science.gov (United States)

    Gil-Bona, Ana; Reales-Calderon, Jose A.; Parra-Giraldo, Claudia M.; Martinez-Lopez, Raquel; Monteoliva, Lucia; Gil, Concha

    2016-01-01

    Ecm33 is a glycosylphosphatidylinositol-anchored protein in the human pathogen Candida albicans. This protein is known to be involved in fungal cell wall integrity (CWI) and is also critical for normal virulence in the mouse model of hematogenously disseminated candidiasis, but its function remains unknown. In this work, several phenotypic analyses of the C. albicans ecm33/ecm33 mutant (RML2U) were performed. We observed that RML2U displays the inability of protoplast to regenerate the cell wall, activation of the CWI pathway, hypersensitivity to temperature, osmotic and oxidative stresses and a shortened chronological lifespan. During the exponential and stationary culture phases, nuclear and actin staining revealed the possible arrest of the cell cycle in RML2U cells. Interestingly, a “veil growth,” never previously described in C. albicans, was serendipitously observed under static stationary cells. The cells that formed this structure were also observed in cornmeal liquid cultures. These cells are giant, round cells, without DNA, and contain large vacuoles, similar to autophagic cells observed in other fungi. Furthermore, RML2U was phagocytozed more than the wild-type strain by macrophages at earlier time points, but the damage caused to the mouse cells was less than with the wild-type strain. Additionally, the percentage of RML2U apoptotic cells after interaction with macrophages was fewer than in the wild-type strain. PMID:26870022

  12. The cell wall protein Ecm33 of Candida albicans is involved in chronological life span, morphogenesis, cell wall regeneration, stress tolerance and host-cell interaction

    Directory of Open Access Journals (Sweden)

    Ana eGil-Bona

    2016-02-01

    Full Text Available Ecm33 is a glycosylphosphatidylinositol (GPI-anchored protein in the human pathogen Candida albicans. This protein is known to be involved in fungal cell wall integrity and is also critical for normal virulence in the mouse model of hematogenously disseminated candidiasis, but its function remains unknown. In this work, several phenotypic analyses of the C. albicans ecm33/ecm33 mutant (RML2U were performed. We observed that RML2U displays the inability of protoplast to regenerate the cell wall, activation of the cell wall integrity pathway, hypersensitivity to temperature, osmotic and oxidative stresses and a shortened chronological lifespan. During the exponential and stationary culture phases, nuclear and actin staining revealed the possible arrest of the cell cycle in RML2U cells. Interestingly, a veil growth, never previously described in C. albicans, was serendipitously observed under static stationary cells. The cells that formed this structure were also observed in cornmeal liquid cultures. These cells are giant, round cells, without DNA, and contain large vacuoles, similar to autophagic cells observed in other fungi. Furthermore, RML2U was phagocytozed more than the wild-type strain by macrophages at earlier time points, but the damage caused to the mouse cells was less than with the wild-type strain. Additionally, the percentage of RML2U apoptotic cells after interaction with macrophages was fewer than in the wild-type strain.

  13. Thermodynamics and life span estimation

    International Nuclear Information System (INIS)

    Kuddusi, Lütfullah

    2015-01-01

    In this study, the life span of people living in seven regions of Turkey is estimated by applying the first and second laws of thermodynamics to the human body. The people living in different regions of Turkey have different food habits. The first and second laws of thermodynamics are used to calculate the entropy generation rate per unit mass of a human due to the food habits. The lifetime entropy generation per unit mass of a human was previously found statistically. The two entropy generations, lifetime entropy generation and entropy generation rate, enable one to determine the life span of people living in seven regions of Turkey with different food habits. In order to estimate the life span, some statistics of Turkish Statistical Institute regarding the food habits of the people living in seven regions of Turkey are used. The life spans of people that live in Central Anatolia and Eastern Anatolia regions are the longest and shortest, respectively. Generally, the following inequality regarding the life span of people living in seven regions of Turkey is found: Eastern Anatolia < Southeast Anatolia < Black Sea < Mediterranean < Marmara < Aegean < Central Anatolia. - Highlights: • The first and second laws of thermodynamics are applied to the human body. • The entropy generation of a human due to his food habits is determined. • The life span of Turks is estimated by using the entropy generation method. • Food habits of a human have effect on his life span

  14. Sexual conflict, life span, and aging.

    Science.gov (United States)

    Adler, Margo I; Bonduriansky, Russell

    2014-06-17

    The potential for sexual conflict to influence the evolution of life span and aging has been recognized for more than a decade, and recent work also suggests that variation in life span and aging can influence sexually antagonistic coevolution. However, empirical exploration of these ideas is only beginning. Here, we provide an overview of the ideas and evidence linking inter- and intralocus sexual conflicts with life span and aging. We aim to clarify the conceptual basis of this research program, examine the current state of knowledge, and suggest key questions for further investigation. Copyright © 2014 Cold Spring Harbor Laboratory Press; all rights reserved.

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

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    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.

  16. 'Localised creativity: a life span perspective'

    OpenAIRE

    Worth, Piers J.

    2000-01-01

    This thesis is based around a biographic study of the lives of 40 individuals (24 men and 16 women) with a reputation for creative work in a localised context (such as an organisation). The study examines life span development patterns from birth to middle age (45 - 60 years of age) with data gained by biographic interview and thematic analysis. Participants selected for this study are creative in that they have a reputation for producing new, novel and useful or appropriate contributions in ...

  17. Life span study report, 11, part 2

    International Nuclear Information System (INIS)

    Shimizu, Yukiko; Kato, Hiroo; Schull, W.J.

    1988-12-01

    ABCC and its successor, RERF, have followed since 1959 and retrospectively to 1950 the mortality in a fixed cohort of survivors of the atomic bombings of Hiroshima and Nagasaki, the so-called Life Span Study sample. The present study, the 11th in a series that began in 1961, extends the surveillance period three more years and covers the period 1950-85. It is based on the recently revised dose system, called DS86, that has replaced previous estimates of individual exposures. The impact of the change from the old system of dosimetry, the T65DR, to the new on the dose-response relationships for cancer mortality was described in the first of this series of reports. Here, the focus is on cancer mortality among the 76,000 A-bomb survivors within the LSS sample for whom DS86 doses have been estimated, with the emphasis on biological issues associated with radiation carcinogenesis. (author)

  18. Life span study report 9, part 3

    International Nuclear Information System (INIS)

    Wakabayashi, Toshiro; Kato, Hiroo; Ikeda, Takayoshi; Schull, W.J.

    1983-04-01

    The incidence of malignant tumors in the RERF Life Span Study (LSS) sample in Nagasaki as revealed by the Nagasaki Tumor Registry (Registry) has been investigated for the period 1959-78. No exposure status bias in data collection has been revealed. Neither method of diagnosis, reporting hospitals, nor the frequency of doubtful cases differ by exposure dose. Thus, the effect of a bias, if one exists, must be small and should not affect the interpretation of the results obtained in the present analysis. The risk of radiogenic cancer definitely increases with radiation dose for leukemia, cancer of the breast, lung, stomach, and thyroid, and suggestively so for cancer of the colon and urinary tract and multiple myeloma. However, there is no increase as yet for cancer of the esophagus, liver, gall bladder, uterus, ovary, and salivary gland, or for malignant lymphoma. For fatal cancers, these results strengthen those of the recent analysis of mortality based on death certificates on the same LSS cohort. In general, the relative risks based on incidence (that is, on Registry data) are either the same or slightly higher than those based on mortality for the same years; however, the absolute risk estimates (excess cancer per million person-year per rad) are far higher. (author)

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

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    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.

  20. Developmental Regulation across the Life Span: Toward a New Synthesis

    Science.gov (United States)

    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…

  1. Paternal smoking habits affect the reproductive life span of daughters

    DEFF Research Database (Denmark)

    Fukuda, Misao; Fukuda, Kiyomi; Shimizu, Takashi

    2011-01-01

    The present study assessed whether the smoking habits of fathers around the time of conception affected the period in which daughters experienced menstrual cycles (i.e., the reproductive life span). The study revealed that the smoking habits of the farther shortened the daughters' reproductive life...... span compared with daughters whose fathers did not smoke....

  2. A Motivational Theory of Life-Span Development

    Science.gov (United States)

    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…

  3. Decision making across the life span

    NARCIS (Netherlands)

    Li, S.C.; Ridderinkhof, K.R.; Samanez-Larkin, G.R.

    2014-01-01

    Learning to choose adaptively between different behavioral options in order to reach goals is a pervasive task in life for people of all ages. Individuals are often confronted with complex, uncertain situations that nonetheless require decisive actions that would facilitate the pursuit of short-term

  4. Paternal smoking habits affect the reproductive life span of daughters.

    Science.gov (United States)

    Fukuda, Misao; Fukuda, Kiyomi; Shimizu, Takashi; Nobunaga, Miho; Andersen, Elisabeth Wreford; Byskov, Anne Grete; Andersen, Claus Yding

    2011-06-30

    The present study assessed whether the smoking habits of fathers around the time of conception affected the period in which daughters experienced menstrual cycles (i.e., the reproductive life span). The study revealed that the smoking habits of the farther shortened the daughters' reproductive life span compared with daughters whose fathers did not smoke. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. Life Span Exercise Among Elite Intercollegiate Student Athletes

    OpenAIRE

    Sorenson, Shawn C.; Romano, Russell; Azen, Stanley P.; Schroeder, E. Todd; Salem, George J.

    2015-01-01

    Background: Despite prominent public attention, data on life span health and exercise outcomes among elite, competitive athletes are sparse and do not reflect the diversity of modern athletes. Hypothesis: Life span exercise behavior differs between National Collegiate Athletic Association (NCAA) student athletes and a nonathlete control group. Sustained exercise is associated with improved cardiopulmonary health outcomes. Study Design: Cross-sectional, descriptive epidemiology study. Level of...

  6. Life span extension and neuronal cell protection by Drosophila nicotinamidase.

    Science.gov (United States)

    Balan, Vitaly; Miller, Gregory S; Kaplun, Ludmila; Balan, Karina; Chong, Zhao-Zhong; Li, Faqi; Kaplun, Alexander; VanBerkum, Mark F A; Arking, Robert; Freeman, D Carl; Maiese, Kenneth; Tzivion, Guri

    2008-10-10

    The life span of model organisms can be modulated by environmental conditions that influence cellular metabolism, oxidation, or DNA integrity. The yeast nicotinamidase gene pnc1 was identified as a key transcriptional target and mediator of calorie restriction and stress-induced life span extension. PNC1 is thought to exert its effect on yeast life span by modulating cellular nicotinamide and NAD levels, resulting in increased activity of Sir2 family class III histone deacetylases. In Caenorhabditis elegans, knockdown of a pnc1 homolog was shown recently to shorten the worm life span, whereas its overexpression increased survival under conditions of oxidative stress. The function and regulation of nicotinamidases in higher organisms has not been determined. Here, we report the identification and biochemical characterization of the Drosophila nicotinamidase, D-NAAM, and demonstrate that its overexpression significantly increases median and maximal fly life span. The life span extension was reversed in Sir2 mutant flies, suggesting Sir2 dependence. Testing for physiological effectors of D-NAAM in Drosophila S2 cells, we identified oxidative stress as a primary regulator, both at the transcription level and protein activity. In contrast to the yeast model, stress factors such as high osmolarity and heat shock, calorie restriction, or inhibitors of TOR and phosphatidylinositol 3-kinase pathways do not appear to regulate D-NAAM in S2 cells. Interestingly, the expression of D-NAAM in human neuronal cells conferred protection from oxidative stress-induced cell death in a sirtuin-dependent manner. Together, our findings establish a life span extending the ability of nicotinamidase in flies and offer a role for nicotinamide-modulating genes in oxidative stress regulated pathways influencing longevity and neuronal cell survival.

  7. Radiation effects on life span in Caenorhabditis elegans

    International Nuclear Information System (INIS)

    Johnson, T.E.; Hartman, P.S.

    1988-01-01

    Wild-type and radiation-sensitive (Rad) mutants of Caenorhabditis elegans were irradiated using a 137 Cs source (2.7 krads/min.) at several developmental stages and subsequently monitored for life span. Acute doses of radiation ranged from 1 krad to 300 krads. All stages required doses above 100 krads to reduce mean life span. Dauers and third stage larvae were more sensitive, and 8-day-old adults were the most resistant. Occasional statistically significant but nonrepeatable increases in survival were observed after intermediate levels of irradiation (10-30 krads). Unirradiated rad-4 and rad-7 had life spans similar to wild-type; all others had a significant reduction in survival. The mutants were about as sensitive as wild-type to the effects of ionizing radiation including occasional moderate life span extensions at intermediate doses. We conclude that the moderate life span extensions sometimes observed after irradiation are likely to be mediated by a means other than the induction of DNA repair enzymes

  8. Individual differences in personality change across the adult life span.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  10. Life span of animals under acute and chronic irradiation

    International Nuclear Information System (INIS)

    Zapol'skaya, N.A.; Fedorova, A.V.; Borisova, V.V.

    1978-01-01

    The study has been designed to see to what extent a single and long-term external and internal irradiations shorten the life span of animals. LDsub(50/30) for certain radionuclides whose absorbed doses show different spatiotemporal distributions are considered. It has been found that as far as the average life span is concerned, 137 Cs and 90 Sr have approximately the same effect whether they enter the body on a single occasion or repeatedly. With chronic total-body external gamma-irradiation, the decrease in life span is 5 times smaller than than with single-occasion irradiation. The main reason for the observed differences are found to be differences in the rates with which the absorbed doses are formed

  11. Life Span and Resiliency Theory: A Critical Review

    Directory of Open Access Journals (Sweden)

    Alexa Smith-Osborne

    2007-05-01

    Full Text Available Theories of life span development describe human growth and change over the life cycle (Robbins, Chatterjee, & Canda, 2006. Major types of developmental theories include biological, psychodynamic, behavioral, and social learning, cognitive, moral, and spiritual, and those influenced by systems, empowerment, and conflict theory. Life span development theories commonly focus on ontogenesis and sequential mastery of skills, tasks, and abilities. Social work scholars have pointed out that a limitation of life span and other developmental theory is lack of attention to resilience (Greene, 2007; Robbins et al., 1998. The concept of resilience was developed to “describe relative resistance to psychosocial risk experiences” (Rutter, 1999b, p. 119. Longitudinal studies focused on typical and atypical child development informed theory formulation in developmental psychopathology (Garmezy & Rutter, 1983; Luthar, Cichetti,& Becker, 2000 and in an evolving resilience model (Richardson, 2002; Werner & Smith, 1992. Research on resilience has found a positive relationship between a number of individual traits and contextual variables and resistance to a variety of risk factors among children and adolescents. More recently, resilience research has examined the operation of these same factors in the young adult, middle-age, and elder life stages. This article examines the historical and conceptual progression of the two developmental theories—life span and resiliency—and discusses their application to social work practice and education in human behavior in the social environment.

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

    Science.gov (United States)

    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.

  13. Decision-making heuristics and biases across the life span

    Science.gov (United States)

    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

  14. Decision-making heuristics and biases across the life span.

    Science.gov (United States)

    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.

  15. Life Span Approach to Growth and Human Development: A Broad ...

    African Journals Online (AJOL)

    The traditional approach to the study of development emphasizes extensive change in childhood. ... the paper draws the reader's attention to the fact that by adopting the life-span perspective, we gain insights into what our lives will be like as we grow into middle age or old age, who we are, how we came to be this way and ...

  16. Neuromodulation of Behavioral and Cognitive Development across the Life Span

    Science.gov (United States)

    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…

  17. Fatigue life assessment of free spanning pipelines containing corrosion defects

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Rita de Kassia D.; Campello, Georga C.; Matt, Cyntia G. da Costa; Benjamin, Adilson C.; Franciss, Ricardo [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2009-12-19

    The free spanning pipelines assessment is a highlighted issue to be considered during the project and maintenance of the submarine pipelines. It is required to evaluate the fatigue life and the maximum stress due to VIV (Vortex Induced Vibration) as well as wave forces when applicable in case of shallow water. The code DNV-RP-F105 (2006) presents a methodology to calculate the fatigue life for free spanning pipelines. Such methodology however considers the pipe with no kind of defects. Nevertheless, sometimes corrosion defects are detected in periodic inspections and therefore their effects need to be taken into account in the fatigue life evaluation. The purpose of this paper thus is to present a procedure to assess the influence of the corrosion defects in the fatigue life of free spanning pipelines. Some FE analyses were performed to determine the stress concentrate factor (SCF) of the corrosion defects, which were used as input in the methodology presented in the code DNV-RP-F105 (2006). Curves of damage and so lifetime have been generated as function of the span length and water depth. As a practical application, this methodology was applied to a sub sea pipeline with several corrosion defects, localized in shallow water offshore Brazil. (author)

  18. DIRECT SELECTION ON LIFE-SPAN IN DROSOPHILA-MELANOGASTER

    NARCIS (Netherlands)

    ZWAAN, B; BIJLSMA, R; HOEKSTRA, RE

    An important issue in the study of the evolution of aging in Drosophila melanogaster is whether decreased early fecundity is inextricably coupled with increased life span in selection experiments on age at reproduction. Here, this problem has been tackled using an experimental design in which

  19. Age differences in five personality domains across the life span

    NARCIS (Netherlands)

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

    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

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

    Science.gov (United States)

    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…

  1. Tor1/Sch9-regulated carbon source substitution is as effective as calorie restriction in life span extension.

    Directory of Open Access Journals (Sweden)

    Min Wei

    2009-05-01

    Full Text Available The effect of calorie restriction (CR on life span extension, demonstrated in organisms ranging from yeast to mice, may involve the down-regulation of pathways, including Tor, Akt, and Ras. Here, we present data suggesting that yeast Tor1 and Sch9 (a homolog of the mammalian kinases Akt and S6K is a central component of a network that controls a common set of genes implicated in a metabolic switch from the TCA cycle and respiration to glycolysis and glycerol biosynthesis. During chronological survival, mutants lacking SCH9 depleted extracellular ethanol and reduced stored lipids, but synthesized and released glycerol. Deletion of the glycerol biosynthesis genes GPD1, GPD2, or RHR2, among the most up-regulated in long-lived sch9Delta, tor1Delta, and ras2Delta mutants, was sufficient to reverse chronological life span extension in sch9Delta mutants, suggesting that glycerol production, in addition to the regulation of stress resistance systems, optimizes life span extension. Glycerol, unlike glucose or ethanol, did not adversely affect the life span extension induced by calorie restriction or starvation, suggesting that carbon source substitution may represent an alternative to calorie restriction as a strategy to delay aging.

  2. Evaluating the life cycle environmental impact of short span bridges

    DEFF Research Database (Denmark)

    Du, Guangli; Pettersson, Lars; Karoumi, Raid

    2016-01-01

    impact of the construction sector. Life cycle assessment (LCA) is a systematic method for assessing the environmental impact of products and systems, but its application in bridges is scarce. In Swede, most of the bridges are short spans and the type of concrete slab-frame bridge (CFB) accounts...... for a large share. Soil steel composite bridge (SSCB) is a functional equivalent solution for CFB. In order to mitigate the environmental burdens of short span bridges, this paper performed a comparative LCA study between these two types of bridge. The results indicate that the initial material consumption...

  3. Orion: a glimpse of hope in life span extension?

    Science.gov (United States)

    Muradian, K; Bondar, V; Bezrukov, V; Zhukovsky, O; Polyakov, V; Utko, N

    2010-01-01

    Orion is a multicomponent drug based on derivatives of taurocholic acid and several other compounds. Application of Orion into the feeding medium of Drosophila melanogaster resulted in increased life span and survival at stressful conditions. Two paradoxical features of the drug should be stressed: The "age-threshold" (life span extension was observed only when the drug was applied starting from the second half of life) and induction of "centenarian" flies (older 100 days). Orion enhanced survival at heat shock (38 degrees C) and acidic (pH = 1.6) or alkaline (pH = 11.8) feeding mediums, but not at oxidative stresses modeled by 100% oxygen or application of hydrogen peroxide (H(2)O(2)).

  4. [The evolution of plant life span: facts and hypotheses].

    Science.gov (United States)

    2006-01-01

    There are two different views on the evolution of life forms in Cormophyta: from woody plants to herbaceous ones or in opposite direction - from herbs to trees. In accordance with these views it is supposed that life span in plants changed in the course of evolution from many years (perennials) to few years (annuals, biennials), or went in reverse - from few years to many years. The author discusses the problems of senescence and longevity in Cormophyta in the context of various hypotheses of ageing (programmed death theory, mutation accumulation, antagonistic pleiotropy, disposable soma, genes of ageing, genes of longevity). Special attention is given to bio-morphological aspects of longevity and cases of non-ageing plants ("negative senescence", "potential immortality"). It is proposed to distinguish seven models of simple ontogenesis in Cormophyta that can exemplify the diversity of mechanisms of ageing and longevity. The evolution of life span in plants is considered as an indirect result of natural selection of other characteristics of organisms or as a consequence of fixation of modifications (episelectional evolution). It seems that short life span could emerge several times during evolution of one group of plants, thus favoring its adaptive radiation.

  5. The Life Span of the BD-PND Bubble Detector

    International Nuclear Information System (INIS)

    Vanhavere, F.; Loos, M.; Thierens, H.

    1999-01-01

    BD-PND bubble detectors from Bubble Technology Industries (BTI) were used to conduct a study of the life span of these detectors. The manufacturer guarantees an optimum detector performance for three months after receipt. Nevertheless, it is important to know the evolution of their characteristics with time, also after those three months. On a standard set-up with a 252 Cf source the bubble detectors were irradiated until they reached the end of their life span. During this period, the evolution in sensitivity was monitored. The temperature compensating system seems to be the limiting factor with time for the use of the BTI bubble detectors. The change in temperature dependence with age was determined. The same parameters were also checked with several batches of detectors that were used in practice. (author)

  6. Life spans of planktonic foraminifers: New sight through sediment traps

    Digital Repository Service at National Institute of Oceanography (India)

    Nigam, R.; Saraswat, R.; Mazumder, A.

    ), indicated by black arrows are remarkably present for all three trap locations. (Modified after Curry et l.t 1992). 2002; Eguchi, Ujiie, Kawahata and Taira 2003), (ii) all the traps can not stop functioning simultaneously and that for the same time... estimates of the life spans of planktonic foraminifera based on extrapolation of lab culture observations. According to Be et al (1981), an inverse relationship exists between feeding frequency and survival time, and that planktonic foraminifers under...

  7. Homeless Aging Veterans in Transition: A Life-Span Perspective

    Directory of Open Access Journals (Sweden)

    Carla J. Thompson

    2013-01-01

    Full Text Available The need for counseling and career/educational services for homeless veterans has captured political and economic venues for more than 25 years. Veterans are three times more likely to become homeless than the general population if veterans live in poverty or are minority veterans. This mixed methods study emphasized a life-span perspective approach for exploring factors influencing normative aging and life-quality of 39 homeless veterans in Alabama and Florida. Seven descriptive quantitative and qualitative research questions framed the investigation. Study participants completed a quantitative survey reflecting their preferences and needs with a subset of the sample (N=12 also participating in individual qualitative interview sessions. Thirty-two service providers and stakeholders completed quantitative surveys. Empirical and qualitative data with appropriate triangulation procedures provided interpretive information relative to a life-span development perspective. Study findings provide evidence of the need for future research efforts to address strategies that focus on the health and economic challenges of veterans before they are threatened with the possibility of homelessness. Implications of the study findings provide important information associated with the premise that human development occurs throughout life with specific characteristics influencing the individual’s passage. Implications for aging/homelessness research are grounded in late-life transitioning and human development intervention considerations.

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

    Science.gov (United States)

    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.

  9. Heritability of life span in the Old Order Amish.

    Science.gov (United States)

    Mitchell, B D; Hsueh, W C; King, T M; Pollin, T I; Sorkin, J; Agarwala, R; Schäffer, A A; Shuldiner, A R

    2001-09-01

    Although a familial contribution to human longevity is recognized, the nature of this contribution is largely unknown. We have examined the familial contribution to life span in the Old Order Amish (OOA) population of Lancaster County, Pennsylvania. Analyses were conducted on 1,655 individuals, representing all those born prior to 1890 and appearing in the most widely available genealogy, surviving until at least age 30 years, and with known date of death. Mean age at death (+/-SD) in this population was 70.7 +/- 15.6 years, and this did not change appreciably over time. Parental and offspring ages at death were significantly correlated, as were ages of death among siblings. Offspring longevity was correlated with longevity of both parents, and in more or less additive fashion. For example, mean offspring age at death was 69.4 +/- 15.3 years in individuals for whom both parents died before the age of 75 years (n = 280) and increased to 73.5 +/- 16.0 years in individuals for whom neither parent died before the age of 75 years (n = 311). These differences were highly significant (P = 0.006). We estimated heritability of life span to be 25% +/- 5%, suggesting that the additive effects of genes account for one quarter of the total variability in life span in the OOA. We conclude that longevity is moderately heritable in the OOA, that the genetic effects are additive, and that genetic influences on longevity are likely to be expressed across a broad range of ages. Published 2001 Wiley-Liss, Inc.

  10. Emotional Egocentricity Bias across the life-span

    Directory of Open Access Journals (Sweden)

    Federica eRiva

    2016-04-01

    Full Text Available 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 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 paradigm which, by making use of visuo-tactile stimulation that elicits conflicting feelings in paired participants, allows the valid and reliable exploration of EEB. Results highlighted a U-shaped relation between age and EEB, revealing higher 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 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 only by the end of adolescence, and displays an early decay in older age. 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

  11. Life-span studies of inhaled plutonium in beagle dogs

    International Nuclear Information System (INIS)

    Bair, W.J.

    1990-04-01

    In 1970 a life-span study with over 300 beagle dogs was begun to gain an understanding of long-term health effects resulting from respiratory tract intakes of plutonium and to derive risk estimates that might be applied to plutonium and other transuranic elements. Groups of beagle dogs were given single exposures to 239 PuO 2 , 238 PuO 2 , or 239 Pu(NO 3 ) 4 to obtain graded levels of initial lung burdens ranging from 1 to 1800 Bq lung. The objective of this paper is to give you a progress report on the current life-span studies of inhaled plutonium in beagle dogs at the Pacific Northwest Laboratory. I will describe the biokinetics of inhaled plutonium in dogs and the resulting health effects. I will also mention some studies directed towards understanding the mechanism leading to these effects. Finally, I will discuss the current risk estimates derived from these studies and how they might relate to plutonium exposures in humans. 5 refs., 13 figs., 4 tabs

  12. SNEV overexpression extends the life span of human endothelial cells

    International Nuclear Information System (INIS)

    Voglauer, Regina; Chang, Martina Wei-Fen; Dampier, Brigitta; Wieser, Matthias; Baumann, Kristin; Sterovsky, Thomas; Schreiber, Martin; Katinger, Hermann; Grillari, Johannes

    2006-01-01

    In a recent screening for genes downregulated in replicatively senescent human umbilical vein endothelial cells (HUVECs), we have isolated the novel protein SNEV. Since then SNEV has proven as a multifaceted protein playing a role in pre-mRNA splicing, DNA repair, and the ubiquitin/proteosome system. Here, we report that SNEV mRNA decreases in various cell types during replicative senescence, and that it is increased in various immortalized cell lines, as well as in breast tumors, where SNEV transcript levels also correlate with the survival of breast cancer patients. Since these mRNA profiles suggested a role of SNEV in the regulation of cell proliferation, the effect of its overexpression was tested. Thereby, a significant extension of the cellular life span was observed, which was not caused by altered telomerase activity or telomere dynamics but rather by enhanced stress resistance. When SNEV overexpressing cells were treated with bleomycin or bleomycin combined with BSO, inducing DNA damage as well as reactive oxygen species, a significantly lower fraction of apoptotic cells was found in comparison to vector control cells. These data suggest that high levels of SNEV might extend the cellular life span by increasing the resistance to stress or by improving the DNA repair capacity of the cells

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

    Science.gov (United States)

    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.

  14. From Suns to Life: A Chronological Approach to the History of Life on Earth

    CERN Document Server

    Gargaud, Muriel; López-García, Purificación; Martin, Hervé; Montmerle, Thierry; Pascal, Robert; Reisse, Jacques

    2006-01-01

    This review emerged from several interdisciplinary meetings and schools gathering a group of astronomers, geologists, biologists, and chemists, attempting to share their specialized knowledge around a common question: how did life emerge on Earth? Their ultimate goal was to provide some kind of answer as a prerequisite to an even more demanding question: is life universal? The resulting state-of-the-art articles were written by twenty-five scientists telling a not-so linear story, but on the contrary, highlighting problems, gaps, and controversies. Needless to say, this approach yielded no definitive answers to both questions. However, by adopting a chronological approach to the question of the emergence of life on Earth, the only place where we know for sure that life exists; it was possible to break down this question into several sub-topics that can be addressed by the different disciplines. The main chapters of this review present the formation and evolution of the solar system (3); the building of a habi...

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

    Directory of Open Access Journals (Sweden)

    Paola Fabrizio

    2010-07-01

    Full Text Available 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.

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

    Science.gov (United States)

    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.

  17. Phenomenon of life span instability in Drosophila melanogaster: Pt. 2

    International Nuclear Information System (INIS)

    Izmaylov, D.M.; Obukhova, L.K.; Okladnova, O.V.; Akifyev, A.P.

    1993-01-01

    The dynamics of life span (LS) have been studied in successive generations of postirradiation and control groups of Drosophila melanogaster, strain D-32, after a single exposure to Co 60 γ-quantum irradiation. It has been shown using mathematical procedures that in all postirradiation generations, with one exception, survival curves retain their canonical shape. This is indicative of the unchangeable nature of LS distribution. The means LS of the progeny of irradiated parents either coincides with control values or can be higher or lower. Moreover, single irradiation results in an altered time-scanning of LS variations in successive generations as compared with controls. The possible origin of LS instability is discussed. (author)

  18. Chronological aging-induced apoptosis in yeast

    OpenAIRE

    Fabrizio, Paola; Longo, Valter D.

    2008-01-01

    Saccharomyces cerevisiae is the simplest among the major eukaryotic model organisms for aging and diseases. Longevity in the chronological life span paradigm is measured as the mean and maximum survival period of populations of non-dividing yeast. This paradigm has been used successfully to identify several life-regulatory genes and three evolutionary conserved pro-aging pathways. More recently, Schizosaccharomyces pombe has been shown to age chronologically in a manner that resembles that of...

  19. A New Chronology for Rhafas, Northeast Morocco, Spanning the North African Middle Stone Age through to the Neolithic.

    Science.gov (United States)

    Doerschner, Nina; Fitzsimmons, Kathryn E; Ditchfield, Peter; McLaren, Sue J; Steele, Teresa E; Zielhofer, Christoph; McPherron, Shannon P; Bouzouggar, Abdeljalil; Hublin, Jean-Jacques

    Archaeological sites in northern Africa provide a rich record of increasing importance for the origins of modern human behaviour and for understanding human dispersal out of Africa. However, the timing and nature of Palaeolithic human behaviour and dispersal across north-western Africa (the Maghreb), and their relationship to local environmental conditions, remain poorly understood. The cave of Rhafas (northeast Morocco) provides valuable chronological information about cultural changes in the Maghreb during the Palaeolithic due to its long stratified archaeological sequence comprising Middle Stone Age (MSA), Later Stone Age (LSA) and Neolithic occupation layers. In this study, we apply optically stimulated luminescence (OSL) dating on sand-sized quartz grains to the cave deposits of Rhafas, as well as to a recently excavated section on the terrace in front of the cave entrance. We hereby provide a revised chronostratigraphy for the archaeological sequence at the site. We combine these results with geological and sedimentological multi-proxy investigations to gain insights into site formation processes and the palaeoenvironmental record of the region. The older sedimentological units at Rhafas were deposited between 135 ka and 57 ka (MIS 6 -MIS 3) and are associated with the MSA technocomplex. Tanged pieces start to occur in the archaeological layers around 109 ka, which is consistent with previously published chronological data from the Maghreb. A well indurated duricrust indicates favourable climatic conditions for the pedogenic cementation by carbonates of sediment layers at the site after 57 ka. Overlying deposits attributed to the LSA technocomplex yield ages of ~21 ka and ~15 ka, corresponding to the last glacial period, and fall well within the previously established occupation phase in the Maghreb. The last occupation phase at Rhafas took place during the Neolithic and is dated to ~7.8 ka.

  20. A New Chronology for Rhafas, Northeast Morocco, Spanning the North African Middle Stone Age through to the Neolithic.

    Directory of Open Access Journals (Sweden)

    Nina Doerschner

    Full Text Available Archaeological sites in northern Africa provide a rich record of increasing importance for the origins of modern human behaviour and for understanding human dispersal out of Africa. However, the timing and nature of Palaeolithic human behaviour and dispersal across north-western Africa (the Maghreb, and their relationship to local environmental conditions, remain poorly understood. The cave of Rhafas (northeast Morocco provides valuable chronological information about cultural changes in the Maghreb during the Palaeolithic due to its long stratified archaeological sequence comprising Middle Stone Age (MSA, Later Stone Age (LSA and Neolithic occupation layers. In this study, we apply optically stimulated luminescence (OSL dating on sand-sized quartz grains to the cave deposits of Rhafas, as well as to a recently excavated section on the terrace in front of the cave entrance. We hereby provide a revised chronostratigraphy for the archaeological sequence at the site. We combine these results with geological and sedimentological multi-proxy investigations to gain insights into site formation processes and the palaeoenvironmental record of the region. The older sedimentological units at Rhafas were deposited between 135 ka and 57 ka (MIS 6 -MIS 3 and are associated with the MSA technocomplex. Tanged pieces start to occur in the archaeological layers around 109 ka, which is consistent with previously published chronological data from the Maghreb. A well indurated duricrust indicates favourable climatic conditions for the pedogenic cementation by carbonates of sediment layers at the site after 57 ka. Overlying deposits attributed to the LSA technocomplex yield ages of ~21 ka and ~15 ka, corresponding to the last glacial period, and fall well within the previously established occupation phase in the Maghreb. The last occupation phase at Rhafas took place during the Neolithic and is dated to ~7.8 ka.

  1. Age differences in five personality domains across the life span.

    Science.gov (United States)

    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).

  2. Childhood Self-Control and Unemployment Throughout the Life Span

    Science.gov (United States)

    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

  3. Coping strategies: gender differences and development throughout life span.

    Science.gov (United States)

    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.

  4. Life Span Extension and Neuronal Cell Protection by Drosophila Nicotinamidase*S⃞

    OpenAIRE

    Balan, Vitaly; Miller, Gregory S.; Kaplun, Ludmila; Balan, Karina; Chong, Zhao-Zhong; Li, Faqi; Kaplun, Alexander; VanBerkum, Mark F. A.; Arking, Robert; Freeman, D. Carl; Maiese, Kenneth; Tzivion, Guri

    2008-01-01

    The life span of model organisms can be modulated by environmental conditions that influence cellular metabolism, oxidation, or DNA integrity. The yeast nicotinamidase gene pnc1 was identified as a key transcriptional target and mediator of calorie restriction and stress-induced life span extension. PNC1 is thought to exert its effect on yeast life span by modulating cellular nicotinamide and NAD levels, resulting in increased activity of Sir2 family class III histone ...

  5. Life-span studies of inhaled plutonium in beagle dogs

    International Nuclear Information System (INIS)

    Bair, W.J.

    1991-01-01

    In 1970 a life-span study with over 300 beagle dogs was begun. Groups of beagle dogs were given single exposures to 239 PuO 2 , 238 PuO 2 , or 239 Pu(NO 3 ) 4 to obtain graded levels of initial lung burdens ranging from 1 to 1800 Bq lung. After 16 years, the lungs contained about 2% of the initial lung burden of 239 PuO 2 , the thoracic lymph nodes 20%, skeleton 1% and liver 10%. After 15 years the lungs contained about 0.2% of the initial lung burden of 238 PuO 2 , thoracic lymph nodes 5%, skeleton 10%, and liver 10%. After 10 years the lungs contained about 0.29% of the initial lung burden of 239 Pu(NO 3 ) 4 , thoracic lymph nodes 0.17%, skeleton 18% and liver 13%. Chronic lymphopenia has been one of the earliest biological effects observed. Other effects associated with plutonium exposure included sclerosis of the tracheobronchial lymph nodes, focal radiation pneumonitis, adenomatous hyperplasia of the liver and dystrophic osteolytic lesions in the skeleton. In 16 years, mortality due to radiation pneumonitis and/or lung tumor increased with deposition of 24 Bq of 239 PuO 2 . In 15 years, mortality due to lung and/or bone tumors increased with deposition of 96 Bq of 238 PuO 2 . In 11 years, after exposure, mortality due to lung and/or bone tumors increased with deposition of 18 Bq of 239 Pu(NO 3 ) 4 . Lung cancers appeared to originate in the parenchymal regions of the lungs and were of several types; bronchiolar alveolar carcinoma, papillary adenocarcinomas, adenosquamous carcinoma, and epidermoid carcinoma. Metastases were primarily to the thoracic lymph nodes. Sites of osteosarcomas in the 238 PuO 2 and 239 Pu(NO 3 ) 4 dogs were in the lumbar cervical and thoracic vertebrae, humerus, pelvis, facial bones, ribs and nasal turbinates. The risk of lung cancer, based on cumulative dose to the lungs, was about 12 times higher for 239 Pu(NO 3 ) 4 than from inhaled 239 PuO 2 , and 50 times higher than for inhaled 238 PuO 2 . (J.P.N.)

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  9. The Influence of Dietary Fat Source on Life Span in Calorie Restricted Mice.

    Science.gov (United States)

    López-Domínguez, José A; Ramsey, Jon J; Tran, Dianna; Imai, Denise M; Koehne, Amanda; Laing, Steven T; Griffey, Stephen M; Kim, Kyoungmi; Taylor, Sandra L; Hagopian, Kevork; Villalba, José M; López-Lluch, Guillermo; Navas, Plácido; McDonald, Roger B

    2015-10-01

    Calorie restriction (CR) without malnutrition extends life span in several animal models. It has been proposed that a decrease in the amount of polyunsaturated fatty acids (PUFAs), and especially n-3 fatty acids, in membrane phospholipids may contribute to life span extension with CR. Phospholipid PUFAs are sensitive to dietary fatty acid composition, and thus, the purpose of this study was to determine the influence of dietary lipids on life span in CR mice. C57BL/6J mice were assigned to four groups (a 5% CR control group and three 40% CR groups) and fed diets with soybean oil (high in n-6 PUFAs), fish oil (high in n-3 PUFAs), or lard (high in saturated and monounsaturated fatty acids) as the primary lipid source. Life span was increased (p Life span was also increased (p life span in mice on CR, and suggest that a diet containing a low proportion of PUFAs and high proportion of monounsaturated and saturated fats may maximize life span in animals maintained on CR. © The Author 2014. 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.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Orozco Helena

    2013-01-01

    Full Text Available Abstract Background 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. Results 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. Conclusions 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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  15. Low doze γ-irradiation influence on drosophila life span in different genetics background

    International Nuclear Information System (INIS)

    Moskalev, A.

    2007-01-01

    Complete text of publication follows. The main goal of this work was to study in Drosophila melanogaster the contribution of DNA damage sensing and repair, apoptosis and heat shock defence into life span and physical activity alteration after gamma-irradiation at low doze rate. In our experiments, the strains were exposed to chronic gamma-irradiation from a 226Ra source (50 R/h) at doze rate 0.17 cGy/h at pre-imago development stages only. The absorbed radiation dose per generation (from embryo to imago, 12 days) was 60 cGy. Life span estimation was prepared in adult males and females separately. We compared the life span of apoptotic (p53, DIAP-1, dApaf-1, Dcp-1, reaper, grim and hid), heat shock defence (HSP70, HSP23, HSF), DNA damage sensing (ATR) and repair (XPF, XPC, PCNA, DSB repair helicase homologs) mutants after chronic irradiation with the control. On the basis of our investigation we have concluded: 1) Low doze irradiation alter the life span depending on genetic background (mutant alleles, heterozygosity level and sex); 2) Age dynamics of physical activity positively correlates with the life span; 3) Longevity potential forms at early development stages; 4) DNA damage sensing, DNA repair, heat shock defence and apoptosis as aging preventing mechanisms play crucial role in radiation-induced life span hormesis.

  16. Leaf life span plasticity in tropical seedlings grown under contrasting light regimes.

    Science.gov (United States)

    Vincent, Gregoire

    2006-02-01

    The phenotypic plasticity of leaf life span in response to low resource conditions has a potentially large impact on the plant carbon budget, notably in evergreen species not subject to seasonal leaf shedding, but has rarely been well documented. This study evaluates the plasticity of leaf longevity, in terms of its quantitative importance to the plant carbon balance under limiting light. Seedlings of four tropical tree species with contrasting light requirements (Alstonia scholaris, Hevea brasiliensis, Durio zibethinus and Lansium domesticum) were grown under three light regimes (full sunlight, 45 % sunlight and 12 % sunlight). Their leaf dynamics were monitored over 18 months. All species showed a considerable level of plasticity with regard to leaf life span: over the range of light levels explored, the ratio of the range to the mean value of life span varied from 29 %, for the least plastic species, to 84 %, for the most. The common trend was for leaf life span to increase with decreasing light intensity. The plasticity apparent in leaf life span was similar in magnitude to the plasticity observed in specific leaf area and photosynthetic rate, implying that it has a significant impact on carbon gain efficiency when plants acclimate to different light regimes. In all species, median survival time was negatively correlated with leaf photosynthetic capacity (or its proxy, the nitrogen content per unit area) and leaf emergence rate. Longer leaf life spans under low light are likely to be a consequence of slower ageing as a result of a slower photosynthetic metabolism.

  17. Does having children extend life span? A genealogical study of parity and longevity in the Amish.

    Science.gov (United States)

    McArdle, Patrick F; Pollin, Toni I; O'Connell, Jeffrey R; Sorkin, John D; Agarwala, Richa; Schäffer, Alejandro A; Streeten, Elizabeth A; King, Terri M; Shuldiner, Alan R; Mitchell, Braxton D

    2006-02-01

    The relationship between parity and life span is uncertain, with evidence of both positive and negative relationships being reported previously. We evaluated this issue by using genealogical data from an Old Order Amish community in Lancaster, Pennsylvania, a population characterized by large nuclear families, homogeneous lifestyle, and extensive genealogical records. The analysis was restricted to the set of 2,015 individuals who had children, were born between 1749 and 1912, and survived until at least age 50 years. Pedigree structures and birth and death dates were extracted from Amish genealogies, and the relationship between parity and longevity was examined using a variance component framework. Life span of fathers increased in linear fashion with increasing number of children (0.23 years per additional child; p =.01), while life span of mothers increased linearly up to 14 children (0.32 years per additional child; p =.004) but decreased with each additional child beyond 14 (p =.0004). Among women, but not men, a later age at last birth was associated with longer life span (p =.001). Adjusting for age at last birth obliterated the correlation between maternal life span and number of children, except among mothers with ultrahigh (>14 children) parity. We conclude that high parity among men and later menopause among women may be markers for increased life span. Understanding the biological and/or social factors mediating these relationships may provide insights into mechanisms underlying successful aging.

  18. Herbal supplement extends life span under some environmental conditions and boosts stress resistance.

    Directory of Open Access Journals (Sweden)

    Bryant Villeponteau

    Full Text Available 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.

  19. Life-span adjustment of children to their parents' divorce.

    Science.gov (United States)

    Amato, P R

    1994-01-01

    Children who experience parental divorce, compared with children in intact two-parent families, exhibit more conduct problems, more symptoms of psychological maladjustment, lower academic achievement, more social difficulties, and poorer self-concepts. Similarly, adults who experienced parental divorce as children, compared with adults raised in continuously intact two-parent families, score lower on a variety of indicators of psychological, interpersonal, and socioeconomic well-being. However, the overall group differences between offspring from divorced and intact families are small, with considerable diversity existing in children's reactions to divorce. Children's adjustment to divorce depends on several factors, including the amount and quality of contact with noncustodial parents, the custodial parents' psychological adjustment and parenting skills, the level of interparental conflict that precedes and follows divorce, the degree of economic hardship to which children are exposed, and the number of stressful life events that accompany and follow divorce. These factors can be used as guides to assess the probable impact of various legal and therapeutic interventions to improve the well-being of children of divorce.

  20. Studies on the life spans of atom-bomb survivors

    International Nuclear Information System (INIS)

    Kato, Hiroo

    1975-01-01

    A shortening of whole life as late injuries of atom-bomb survivors was discussed from the aspects of aging and the studies on the causes of leukemia and cancers. Twenty-one thousands four hundreds and forty-seven of 109000 subjects died during the period between 1950 and 1970. Mortality by exposure doses presented a high value with exposure doses. Mortality of subjects which had received exposure doses of more than 200 rads rose to a level which was 1.27 times in all causes of deaths of the control which had received exposure doses of 0 to 9 rads, and it showed 1.32 times in all deaths of sickness, 18.3 times in leukemia, and 1.48 times in death from cancer. Mortality due to leukemia decreases after 1950-1954, but in the group which had received exposure doses over 100 rads, the mortality was significantly higher than that in all districts in Japan. The shape of dose-reaction curve in Hiroshima was different from that in Nagasaki. In the same dose, mortality due to leukemia in Hiroshima was higher than that in Nagasaki. The younger the age at exposure was, the higher the risk rate of occurring cancer was. Especially, the risk rate of cancer was high in the patients who were exposed to atomic bomb during the age of 0 to 9 years old. Mortality due to cancer increased with the dose. Cancers which statistically showed higher mortality than that in the control group are lung cancer, cancer of the breast (100-199 rad), carcinoma of the esophagus, cancer of the urinary organ (200-299 rad) and gastric cancer (over 300 rads). There are not so clear difference in the mortality due to cancer between Hiroshima and Nagasaki, comparing with the mortality due to leukemia. (Kanao, N.)

  1. Studies on the life spans of atom-bomb survivors

    Energy Technology Data Exchange (ETDEWEB)

    Kato, H [Radiation Effect Research Foundation, Hiroshima (Japan)

    1975-12-01

    A shortening of whole life as late injuries of atom-bomb survivors was discussed from the aspects of aging and the studies on the causes of leukemia and cancers. Twenty-one thousands four hundreds and forty-seven of 109000 subjects died during the period between 1950 and 1970. Mortality by exposure doses presented a high value with exposure doses. Mortality of subjects which had received exposure doses of more than 200 rads rose to a level which was 1.27 times in all causes of deaths of the control which had received exposure doses of 0 to 9 rads, and it showed 1.32 times in all deaths of sickness, 18.3 times in leukemia, and 1.48 times in death from cancer. Mortality due to leukemia decreases after 1950-1954, but in the group which had received exposure doses over 100 rads, the mortality was significantly higher than that in all districts in Japan. The shape of dose-reaction curve in Hiroshima was different from that in Nagasaki. In the same dose, mortality due to leukemia in Hiroshima was higher than that in Nagasaki. The younger the age at exposure was, the higher the risk rate of occurring cancer was. Especially, the risk rate of cancer was high in the patients who were exposed to atomic bomb during the age of 0 to 9 years old. Mortality due to cancer increased with the dose. Cancers which statistically showed higher mortality than that in the control group are lung cancer, cancer of the breast (100-199 rad), carcinoma of the esophagus, cancer of the urinary organ (200-299 rad) and gastric cancer (over 300 rads). There are not so clear difference in the mortality due to cancer between Hiroshima and Nagasaki, comparing with the mortality due to leukemia.

  2. Life Span Extension and Neuronal Cell Protection by Drosophila Nicotinamidase*S⃞

    Science.gov (United States)

    Balan, Vitaly; Miller, Gregory S.; Kaplun, Ludmila; Balan, Karina; Chong, Zhao-Zhong; Li, Faqi; Kaplun, Alexander; VanBerkum, Mark F. A.; Arking, Robert; Freeman, D. Carl; Maiese, Kenneth; Tzivion, Guri

    2008-01-01

    The life span of model organisms can be modulated by environmental conditions that influence cellular metabolism, oxidation, or DNA integrity. The yeast nicotinamidase gene pnc1 was identified as a key transcriptional target and mediator of calorie restriction and stress-induced life span extension. PNC1 is thought to exert its effect on yeast life span by modulating cellular nicotinamide and NAD levels, resulting in increased activity of Sir2 family class III histone deacetylases. In Caenorhabditis elegans, knockdown of a pnc1 homolog was shown recently to shorten the worm life span, whereas its overexpression increased survival under conditions of oxidative stress. The function and regulation of nicotinamidases in higher organisms has not been determined. Here, we report the identification and biochemical characterization of the Drosophila nicotinamidase, D-NAAM, and demonstrate that its overexpression significantly increases median and maximal fly life span. The life span extension was reversed in Sir2 mutant flies, suggesting Sir2 dependence. Testing for physiological effectors of D-NAAM in Drosophila S2 cells, we identified oxidative stress as a primary regulator, both at the transcription level and protein activity. In contrast to the yeast model, stress factors such as high osmolarity and heat shock, calorie restriction, or inhibitors of TOR and phosphatidylinositol 3-kinase pathways do not appear to regulate D-NAAM in S2 cells. Interestingly, the expression of D-NAAM in human neuronal cells conferred protection from oxidative stress-induced cell death in a sirtuin-dependent manner. Together, our findings establish a life span extending the ability of nicotinamidase in flies and offer a role for nicotinamide-modulating genes in oxidative stress regulated pathways influencing longevity and neuronal cell survival. PMID:18678867

  3. Increased Life Span due to Calorie Restriction in Respiratory-Deficient Yeast.

    Directory of Open Access Journals (Sweden)

    2005-11-01

    Full Text Available A model for replicative life span extension by calorie restriction (CR in yeast has been proposed whereby reduced glucose in the growth medium leads to activation of the NAD-dependent histone deacetylase Sir2. One mechanism proposed for this putative activation of Sir2 is that CR enhances the rate of respiration, in turn leading to altered levels of NAD or NADH, and ultimately resulting in enhanced Sir2 activity. An alternative mechanism has been proposed in which CR decreases levels of the Sir2 inhibitor nicotinamide through increased expression of the gene coding for nicotinamidase, PNC1. We have previously reported that life span extension by CR is not dependent on Sir2 in the long-lived BY4742 strain background. Here we have determined the requirement for respiration and the effect of nicotinamide levels on life span extension by CR. We find that CR confers robust life span extension in respiratory-deficient cells independent of strain background, and moreover, suppresses the premature mortality associated with loss of mitochondrial DNA in the short-lived PSY316 strain. Addition of nicotinamide to the medium dramatically shortens the life span of wild type cells, due to inhibition of Sir2. However, even in cells lacking both Sir2 and the replication fork block protein Fob1, nicotinamide partially prevents life span extension by CR. These findings (1 demonstrate that respiration is not required for the longevity benefits of CR in yeast, (2 show that nicotinamide inhibits life span extension by CR through a Sir2-independent mechanism, and (3 suggest that CR acts through a conserved, Sir2-independent mechanism in both PSY316 and BY4742.

  4. Increased life span due to calorie restriction in respiratory-deficient yeast.

    Directory of Open Access Journals (Sweden)

    Matt Kaeberlein

    2005-11-01

    Full Text Available A model for replicative life span extension by calorie restriction (CR in yeast has been proposed whereby reduced glucose in the growth medium leads to activation of the NAD+-dependent histone deacetylase Sir2. One mechanism proposed for this putative activation of Sir2 is that CR enhances the rate of respiration, in turn leading to altered levels of NAD+ or NADH, and ultimately resulting in enhanced Sir2 activity. An alternative mechanism has been proposed in which CR decreases levels of the Sir2 inhibitor nicotinamide through increased expression of the gene coding for nicotinamidase, PNC1. We have previously reported that life span extension by CR is not dependent on Sir2 in the long-lived BY4742 strain background. Here we have determined the requirement for respiration and the effect of nicotinamide levels on life span extension by CR. We find that CR confers robust life span extension in respiratory-deficient cells independent of strain background, and moreover, suppresses the premature mortality associated with loss of mitochondrial DNA in the short-lived PSY316 strain. Addition of nicotinamide to the medium dramatically shortens the life span of wild type cells, due to inhibition of Sir2. However, even in cells lacking both Sir2 and the replication fork block protein Fob1, nicotinamide partially prevents life span extension by CR. These findings (1 demonstrate that respiration is not required for the longevity benefits of CR in yeast, (2 show that nicotinamide inhibits life span extension by CR through a Sir2-independent mechanism, and (3 suggest that CR acts through a conserved, Sir2-independent mechanism in both PSY316 and BY4742.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  8. Towards a sustainable healthy working life : associations between chronological age, functional age and work outcomes

    NARCIS (Netherlands)

    Koolhaas, Wendy; van der Klink, Jac J. L.; Groothoff, Johan W.; Brouwer, Sandra

    Background: The aims of this study were: (i) to determine the relation between chronological and functional age; (ii) to examine the association between chronological age and work outcomes; and (iii) to examine the association between functional age and work outcomes. An overview of the most

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

    Directory of Open Access Journals (Sweden)

    Elizabeth DuPre

    2017-10-01

    Full Text Available 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. The importance of life span perspectives is increasingly apparent in understanding normative interactions of large-scale neurocognitive networks. Although recent work has made significant strides in understanding the functional and structural connectivity of these networks, there has been comparatively little attention to life span trajectories of structural covariance networks. In this study we examine patterns of structural covariance across the life span for six neurocognitive networks. Our results suggest that networks exhibit

  10. Quantifying the Structure of Free Association Networks across the Life Span

    Science.gov (United States)

    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…

  11. Life-span radiation effects studies in animals: what can they tell us

    International Nuclear Information System (INIS)

    Thompson, R.C.

    1984-05-01

    Results from life-span studies in a variety of animal species have found relatively little application in the development of radiation risk factors for various organs of man. This paper discusses possible reasons for this situation and presents recommendations to correct it

  12. Flexible pavement rehabilitation design based on pavement service life time span left

    OpenAIRE

    Gamelyak, I.; Shevchuk, V.

    2005-01-01

    The design of flexible pavement rehabilitation is analysed in terms of durability-cost. A notion of the remaining service life span is described. the model of rehabilitation strategy selection is presented for both design project and operation stages. the results can be used in the pavement management system.

  13. Which HRM practices enhance employee outcomes at work across the life-span?

    NARCIS (Netherlands)

    Veth, Klaske; Korzilius, Hubert P.L.M.; van der Heijden, Beatrice I.J.M.; Emans, Ben; de Lange, Annet H.

    Based on the social exchange theory and on ageing and life-span theories, this paper aims to examine: (1) the relationships between perceived availability and use of HRM practices, and employee outcomes (i.e. work engagement and employability); and (2) how employee age moderates these relationships.

  14. Which HRM practices enhance employee outcomes at work across the life-span?

    NARCIS (Netherlands)

    Veth, K.N.; Korzilius, H.P.L.M.; Heijden, B.I.J.M. van der; Lange, A.H. de; Emans, B.J.M.

    2017-01-01

    Based on the social exchange theory and on ageing and life-span theories, this paper aims to examine: (1) the relationships between perceived availability and use of HRM practices, and employee outcomes (i.e. work engagement and employability); and (2) how employee age moderates these relationships.

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

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

    Science.gov (United States)

    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…

  19. Re-use and life span of gloves | van Palenstein Helderman ...

    African Journals Online (AJOL)

    Re-use and life span of gloves. WH van Palenstein Helderman. Abstract. No Abstract. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about ...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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…

  2. On personality stability and change: main results of Brno longitudinal study on life-span development

    Czech Academy of Sciences Publication Activity Database

    Blatný, Marek

    2007-01-01

    Roč. 51, Supplement (2007), s. 37-49 ISSN 0009-062X R&D Projects: GA ČR(CZ) GA406/06/1408 Institutional research plan: CEZ:AV0Z70250504 Keywords : life-span development * personality stability and change Subject RIV: AN - Psychology Impact factor: 0.133, year: 2007

  3. Investigating the life-span of cork products through a longitudinal approach with users- Interim results

    NARCIS (Netherlands)

    Da Silva Pereira, A.C.; Brezet, J.C.; Pereira, H.; Vogtlander, J.G.

    2012-01-01

    Products with long life-spans are generally preferred form an environmental perspective. This paper addresses the longevity of cork products, and the respective influencing aspects. This is accomplished through a longitudinal study where several cork products are used, and at different moments in

  4. Influence of incorporated radionuclides on the life span of Drosophila melanogaster

    International Nuclear Information System (INIS)

    Koshel', N.M.; Vajserman, O.M.; Vojtenko, V.P.; Kutlakhmedov, Yu.O.; Mikhjejev, O.M.

    2004-01-01

    Influence of incorporated radionuclides ( 137 Cs and 90 Sr) on the life span of Drosophila melanogaster was studied. External irradiation modified the formation of cumulative dose of incorporated radionuclides. All influences leaded to significant (p 90 Sr was higher comparing to 137 Cs

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

    Science.gov (United States)

    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.

  6. Vocabulary Skills in Adulthood: Longitudinal Relations with Cognitive and Personality Measures Across the Life-Span

    Czech Academy of Sciences Publication Activity Database

    Smolík, Filip; Blatný, Marek; Jelínek, Martin; Millová, Katarína; Sobotková, Veronika

    2016-01-01

    Roč. 60, č. 2 (2016), s. 97-105 ISSN 0009-062X R&D Projects: GA ČR GAP407/10/2410 Institutional support: RVO:68081740 Keywords : vocabulary * personality * life-span development * verbal IQ Subject RIV: AN - Psychology Impact factor: 0.242, year: 2016

  7. Repeated intraspecific divergence in life span and aging of African annual fishes along an aridity gradient

    Czech Academy of Sciences Publication Activity Database

    Blažek, Radim; Polačik, Matej; Kačer, P.; Cellerino, A.; Řežucha, Radomil; Methling, Caroline; Tomášek, Oldřich; Syslová, K.; Terzibasi Tozzini, E.; Albrecht, Tomáš; Vrtílek, Milan; Reichard, Martin

    2017-01-01

    Roč. 71, č. 2 (2017), s. 386-402 ISSN 0014-3820 R&D Projects: GA ČR GA13-05872S; GA ČR(CZ) GA16-00291S Institutional support: RVO:68081766 Keywords : Intraspecific variation * life span * neoplasia * pace-of-life syndrome * parallel evolution * reproductive senescence Subject RIV: EG - Zoology OBOR OECD: Ecology Impact factor: 4.201, year: 2016

  8. ETS-4 is a transcriptional regulator of life span in Caenorhabditis elegans.

    Directory of Open Access Journals (Sweden)

    Bargavi Thyagarajan

    2010-09-01

    Full Text Available Aging is a complex phenotype responsive to a plethora of environmental inputs; yet only a limited number of transcriptional regulators are known to influence life span. How the downstream expression programs mediated by these factors (or others are coordinated into common or distinct set of aging effectors is an addressable question in model organisms, such as C. elegans. Here, we establish the transcription factor ETS-4, an ortholog of vertebrate SPDEF, as a longevity determinant. Adult worms with ets-4 mutations had a significant extension of mean life span. Restoring ETS-4 activity in the intestine, but not neurons, of ets-4 mutant worms rescued life span to wild-type levels. Using RNAi, we demonstrated that ets-4 is required post-developmentally to regulate adult life span; thus uncoupling the role of ETS-4 in aging from potential functions in worm intestinal development. Seventy ETS-4-regulated genes, identified by gene expression profiling of two distinct ets-4 alleles and analyzed by bioinformatics, were enriched for known longevity effectors that function in lipid transport, lipid metabolism, and innate immunity. Putative target genes were enriched for ones that change expression during normal aging, the majority of which are controlled by the GATA factors. Also, some ETS-4-regulated genes function downstream of the FOXO factor, DAF-16 and the insulin/IGF-1 signaling pathway. However, epistasis and phenotypic analyses indicate that ets-4 functioned in parallel to the insulin/IGF-1 receptor, daf-2 and akt-1/2 kinases. Furthermore, ets-4 required daf-16 to modulate aging, suggesting overlap in function at the level of common targets that affect life span. In conclusion, ETS-4 is a new transcriptional regulator of aging, which shares transcriptional targets with GATA and FOXO factors, suggesting that overlapping pathways direct common sets of lifespan-related genes.

  9. C. elegans VANG-1 modulates life span via insulin/IGF-1-like signaling.

    Directory of Open Access Journals (Sweden)

    Sebastian J Honnen

    Full Text Available The planar cell polarity (PCP pathway is highly conserved from Drosophila to humans and a PCP-like pathway has recently been described in the nematode Caenorhabditis elegans. The developmental function of this pathway is to coordinate the orientation of cells or structures within the plane of an epithelium or to organize cell-cell intercalation required for correct morphogenesis. Here, we describe a novel role of VANG-1, the only C. elegans ortholog of the conserved PCP component Strabismus/Van Gogh. We show that two alleles of vang-1 and depletion of the protein by RNAi cause an increase of mean life span up to 40%. Consistent with the longevity phenotype vang-1 animals also show enhanced resistance to thermal- and oxidative stress and decreased lipofuscin accumulation. In addition, vang-1 mutants show defects like reduced brood size, decreased ovulation rate and prolonged reproductive span, which are also related to gerontogenes. The germline, but not the intestine or neurons, seems to be the primary site of vang-1 function. Life span extension in vang-1 mutants depends on the insulin/IGF-1-like receptor DAF-2 and DAF-16/FoxO transcription factor. RNAi against the phase II detoxification transcription factor SKN-1/Nrf2 also reduced vang-1 life span that might be explained by gradual inhibition of insulin/IGF-1-like signaling in vang-1. This is the first time that a key player of the PCP pathway is shown to be involved in the insulin/IGF-1-like signaling dependent modulation of life span in C. elegans.

  10. Non-linear impact of glutathione depletion on C. elegans life span and stress resistance

    Directory of Open Access Journals (Sweden)

    Nadine Urban

    2017-04-01

    Full Text Available The redox environment in cells and organisms is set by low-molecular mass and protein-bound thiols, with glutathione (GSH representing a major intracellular redox buffer. Subtle thiol oxidation elicits signal transduction processes and adaptive responses to cope with stressors, whereas highly oxidizing conditions may provoke cell death. We here tested how thiol depletion affects life span, stress resistance and stress signaling in the model organism Caenorhabditis elegans. Diethyl maleate (DEM, an α,β-unsaturated carbonyl compound that conjugates to GSH and other thiols, decreased C. elegans life span at a concentration of 1 mM. In contrast, low and moderate doses of DEM (10–100 µM increased mean and maximum life span and improved resistance against oxidative stress. DEM-induced life span extension was not detectable in worms deficient in either the FoxO orthologue, DAF-16, or the Nrf2 orthologue, SKN-1, pointing to a collaborative role of the two transcription factors in life span extension induced by thiol depletion. Cytoprotective target genes of DAF-16 and SKN-1 were upregulated after at least 3 days of exposure to 100 µM DEM, but not 1 mM DEM, whereas only 1 mM DEM caused upregulation of egl-1, a gene controlled by a p53-orthologue, CEP-1. In order to test whether depletion of GSH may elicit effects similar to DEM, we suppressed GSH biosynthesis in worms by attenuating γ-glutamylcysteine synthetase (gcs-1 expression through RNAi. The decline in GSH levels elicited by gcs-1 knockdown starting at young adult stage did not impair viability, but increased both stress resistance and life expectancy of the worms. In contrast, gcs-1 knockdown commencing right after hatching impaired nematode stress resistance and rendered young adult worms prone to vulval ruptures during egg-laying. Thus, modest decrease in GSH levels in young adult worms may promote stress resistance and life span, whereas depletion of GSH is detrimental to freshly

  11. Non-linear impact of glutathione depletion on C. elegans life span and stress resistance.

    Science.gov (United States)

    Urban, Nadine; Tsitsipatis, Dimitrios; Hausig, Franziska; Kreuzer, Katrin; Erler, Katrin; Stein, Vanessa; Ristow, Michael; Steinbrenner, Holger; Klotz, Lars-Oliver

    2017-04-01

    The redox environment in cells and organisms is set by low-molecular mass and protein-bound thiols, with glutathione (GSH) representing a major intracellular redox buffer. Subtle thiol oxidation elicits signal transduction processes and adaptive responses to cope with stressors, whereas highly oxidizing conditions may provoke cell death. We here tested how thiol depletion affects life span, stress resistance and stress signaling in the model organism Caenorhabditis elegans. Diethyl maleate (DEM), an α,β-unsaturated carbonyl compound that conjugates to GSH and other thiols, decreased C. elegans life span at a concentration of 1mM. In contrast, low and moderate doses of DEM (10-100µM) increased mean and maximum life span and improved resistance against oxidative stress. DEM-induced life span extension was not detectable in worms deficient in either the FoxO orthologue, DAF-16, or the Nrf2 orthologue, SKN-1, pointing to a collaborative role of the two transcription factors in life span extension induced by thiol depletion. Cytoprotective target genes of DAF-16 and SKN-1 were upregulated after at least 3 days of exposure to 100µM DEM, but not 1mM DEM, whereas only 1mM DEM caused upregulation of egl-1, a gene controlled by a p53-orthologue, CEP-1. In order to test whether depletion of GSH may elicit effects similar to DEM, we suppressed GSH biosynthesis in worms by attenuating γ-glutamylcysteine synthetase (gcs-1) expression through RNAi. The decline in GSH levels elicited by gcs-1 knockdown starting at young adult stage did not impair viability, but increased both stress resistance and life expectancy of the worms. In contrast, gcs-1 knockdown commencing right after hatching impaired nematode stress resistance and rendered young adult worms prone to vulval ruptures during egg-laying. Thus, modest decrease in GSH levels in young adult worms may promote stress resistance and life span, whereas depletion of GSH is detrimental to freshly hatched and developing worms

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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 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.

  14. Toward an Integrative Science of Life-Span Development and Aging

    Science.gov (United States)

    Piccinin, Andrea M.

    2010-01-01

    The study of aging demands an integrative life-span developmental framework, involving interdisciplinary collaborations and multiple methodological approaches for understanding how and why individuals change, in both normative and idiosyncratic ways. We highlight and summarize some of the issues encountered when conducting integrative research for understanding aging-related change, including, the integration of results across different levels of analysis; the integration of theory, design, and analysis; and the synthesis of results across studies of aging. We emphasize the necessity of longitudinal designs for understanding development and aging and discuss methodological issues that should be considered for achieving reproducible research on within-person processes. It will be important that current and future studies permit opportunities for quantitative comparison across populations given the extent to which historical shifts and cultural differences influence life-span processes and aging-related outcomes. PMID:20237144

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  17. Radiation sensitivity and DNA repair in Caenorhabditis elegans strains with different mean life spans

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, P S; Simpson, V J; Johnson, T; Mitchell, D

    1988-06-01

    The sensitivities to three DNA damaging agents (UV and ..gamma..-radiation, methyl methanesulfonate) were measured in four recombinant inbred (RI) strains of Caenorhabditis elegans with mean life spans ranging from 13 to 30.9 days, as well as in the wild-type strains used to derive these RI's. Sensitivities at several stages in the developmental cycle were tested. There were no significant correlations between mean life span and the lethal effects of these 3 agents. Excision of two UV-radiation-induced DNA photoproducts was also measured. Long-lived strains were no more repair competent than shorter-lived strains. These data indicate that DNA repair plays at best a minor role in the aging process of C. elegans. 33 refs.; 4 figs.

  18. Diabetes mellitus as a cause of life span shortening in locally exposed rats

    International Nuclear Information System (INIS)

    Vershinina, S.F.; Markochev, A.B.

    1992-01-01

    A study was made of the development of remote radiation pathology of pancreas in male rats after local irradiation of abdomen with doses of 5, 10 (two fractions of 5 Gy at a 30-day interval) and 15 Gy (three fractions of 5 Gy at a 30-day interval). The clinical and morphological estimates show the dose-dependent development of diabetes mellitus and 1.8-fold shortening of the life span, as compared to biological control

  19. Implication of Ca2+ in the Regulation of Replicative Life Span of Budding Yeast*

    OpenAIRE

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

    2011-01-01

    In eukaryotic cells, Ca2+-triggered signaling pathways are used to regulate a wide variety of cellular processes. Calcineurin, a highly conserved Ca2+/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 Ca2+ sensitivity of zds1Δ cells in the budding yeast Saccharomyces cerevisiae. Therefore, ...

  20. Leaf life span plasticity in tropical seedlings grown under contrasting light regimes

    OpenAIRE

    Vincent, Grégoire

    2006-01-01

    Background and Aims The phenotypic plasticity of leaf life span in response to low resource conditions has a potentially large impact on the plant carbon budget, notably in evergreen species not subject to seasonal leaf shedding, but has rarely been well documented. This study evaluates the plasticity of leaf longevity, in terms of its quantitative importance to the plant carbon balance under limiting light. Methods Seedlings of four tropical tree species with contrasting light requirements (...

  1. Compassionate Love for a Romantic Partner Across the Adult Life Span

    OpenAIRE

    Neto, Félix; Wilks, Daniela C.

    2017-01-01

    Compassionate love has received research attention over the last decade, but it is as yet unclear how it is experienced over a lifetime. The purpose of this study was to investigate compassionate love for a romantic partner throughout the adult life span, exploring individual differences in the propensity to experience compassionate love in regard to age, gender, religion, love status, love styles, and subjective well-being. The results showed that religion and love status display significant...

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

    OpenAIRE

    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 Seekin...

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

    Science.gov (United States)

    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...

  4. The rate of source memory decline across the adult life span.

    Science.gov (United States)

    Cansino, Selene; Estrada-Manilla, Cinthya; Hernández-Ramos, Evelia; Martínez-Galindo, Joyce Graciela; Torres-Trejo, Frine; Gómez-Fernández, Tania; Ayala-Hernández, Mariana; Osorio, David; Cedillo-Tinoco, Melisa; Garcés-Flores, Lissete; Gómez-Melgarejo, Sandra; Beltrán-Palacios, Karla; Guadalupe García-Lázaro, Haydée; García-Gutiérrez, Fabiola; Cadena-Arenas, Yadira; Fernández-Apan, Luisa; Bärtschi, Andrea; Resendiz-Vera, Julieta; Rodríguez-Ortiz, María Dolores

    2013-05-01

    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 the ages of 21 and 80. Initially, images of common objects were randomly presented on one quadrant of a screen while the participants judged whether they were natural or artificial. During the retrieval phase, these same images were mixed with new ones, and all images were displayed in the center of the screen. The participants were asked to judge whether each image was new or old, and whether it was old, to indicate in which quadrant of the screen it had originally been presented. Source accuracy decreased linearly with advancing age at a rate of 0.6% per year across all decades even after controlling for educational level; this decline was unaffected by sex. These results reveal that either spatial information becomes less efficiently bound to episodic representations over time or that the ability to retrieve this information decreases gradually throughout the adult life span.

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

    Science.gov (United States)

    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.

  6. Trade-off between cellular immunity and life span in mealworm beetles Tenebrio molitor

    Directory of Open Access Journals (Sweden)

    Indrikis KRAMS, Janīna DAUKŠTE, Inese KIVLENIECE, Ants KAASIK, Tatjana KRAMA, Todd M. REEBERG, Markus J. RANTALA

    2013-06-01

    Full Text Available Encapsulation is a nonspecific, cellular response through which insects defend themselves against multicellular pathogens. During this immune reaction, haemocytes recognize an object as foreign and cause other haemocytes to aggregate and form a capsule around the object, often consisting of melanized cells. The process of melanisation is accompanied by the formation of potentially toxic reactive oxygen species, which can kill not only pathogens but also host cells. In this study we tested whether the encapsulation response is costly in mealworm beetles Tenebrio molitor. We found a negative relationship between the duration of implantation via a nylon monofilament and remaining life span. We also found a negative relationship between the strength of immune response and remaining life span, suggesting that cellular immunity is costly in T. molitor, and that there is a trade-off between immune response and remaining life span. However, this relationship disappeared at 31-32 hours of implantation at 25 ± 2℃. As the disappearance of a relationship between duration of implantation and lifespan coincided with the highest values of encapsulation response, we concluded that the beetles stopped investment in the production of melanotic cells, as the implant, a synthetic parasite, was fully isolated from the host’s tissues [Current Zoology 59 (3: 340–346, 2013].

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.).

  12. Tool Wear and Life Span Variations in Cold Forming Operations and Their Implications in Microforming

    Directory of Open Access Journals (Sweden)

    Anders E. W. Jarfors

    2016-12-01

    Full Text Available The current paper aims to review tooling life span, failure modes and models in cold microforming processes. As there is nearly no information available on tool-life for microforming the starting point was conventional cold forming. In cold forming common failures are (1 over stressing of the tool; (2 abrasive wear; (3 galling or adhesive wear, and (4 fatigue failure. The large variation in tool life observed in production and how to predict this was reviewed as this is important to the viability of microforming based on that the tooling cost takes a higher portion of the part cost. Anisotropic properties of the tool materials affect tool life span and depend on both the as-received and in-service conditions. It was concluded that preconditioning of the tool surface, and coating are important to control wear and fatigue. Properly managed, the detrimental effects from surface particles can be reduced. Under high stress low-cycle fatigue conditions, fatigue failure form internal microstructures and inclusions are common. To improve abrasive wear resistance larger carbides are commonly the solution which will have a negative impact on tooling life as these tend to be the root cause of fatigue failures. This has significant impact on cold microforming.

  13. The Japanese diet from 1975 delays senescence and prolongs life span in SAMP8 mice.

    Science.gov (United States)

    Yamamoto, Kazushi; E, Shuang; Hatakeyama, Yu; Sakamoto, Yu; Honma, Taro; Jibu, Yuri; Kawakami, Yuki; Tsuduki, Tsuyoshi

    2016-01-01

    Life expectancy in Japan is high, suggesting that the Japanese diet, Nihon shoku (Japanese food), has significant health benefits. However, these benefits have been called into question over the past 50 y, during which time the Japanese diet has become increasingly Westernized. The aim of the present study was to focus on senescence delay and to examine the effects of Japanese diets from different years to identify which Japanese diet is most effective in enhancing life expectancy and delaying senescence. Weekly menus from the years 1960, 1975, 1990, and 2005 were reproduced based on the National Health and Nutrition Survey in Japan and prepared as powdered foods. The senescence-accelerated mouse prone 8 (SAMP8) mice were fed standard laboratory chow supplemented with a 30% mix of Japanese meals from various years ad libitum throughout their lifetime. Additionally, the control group was given standard laboratory chow only, to examine the development of mice reared under standard conditions. In the group that ingested the traditional 1975 Japanese diet, life span was prolonged, senescence was delayed, and learning and memory capacities were maintained compared with the group fed the 2005 Japanese diet. The life span of the group that ingested the 1990 Japanese diet showed a tendency to be longer than SAMP8 mice fed the 2005 diet. The results of the present study suggested that the traditional Japanese diet is more effective in enhancing life expectancy and delaying senescence than the current Japanese diet. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Life span and reproductive cost explain interspecific variation in the optimal onset of reproduction.

    Science.gov (United States)

    Mourocq, Emeline; Bize, Pierre; Bouwhuis, Sandra; Bradley, Russell; Charmantier, Anne; de la Cruz, Carlos; Drobniak, Szymon M; Espie, Richard H M; Herényi, Márton; Hötker, Hermann; Krüger, Oliver; Marzluff, John; Møller, Anders P; Nakagawa, Shinichi; Phillips, Richard A; Radford, Andrew N; Roulin, Alexandre; Török, János; Valencia, Juliana; van de Pol, Martijn; Warkentin, Ian G; Winney, Isabel S; Wood, Andrew G; Griesser, Michael

    2016-02-01

    Fitness can be profoundly influenced by the age at first reproduction (AFR), but to date the AFR-fitness relationship only has been investigated intraspecifically. Here, we investigated the relationship between AFR and average lifetime reproductive success (LRS) across 34 bird species. We assessed differences in the deviation of the Optimal AFR (i.e., the species-specific AFR associated with the highest LRS) from the age at sexual maturity, considering potential effects of life history as well as social and ecological factors. Most individuals adopted the species-specific Optimal AFR and both the mean and Optimal AFR of species correlated positively with life span. Interspecific deviations of the Optimal AFR were associated with indices reflecting a change in LRS or survival as a function of AFR: a delayed AFR was beneficial in species where early AFR was associated with a decrease in subsequent survival or reproductive output. Overall, our results suggest that a delayed onset of reproduction beyond maturity is an optimal strategy explained by a long life span and costs of early reproduction. By providing the first empirical confirmations of key predictions of life-history theory across species, this study contributes to a better understanding of life-history evolution. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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 students (P 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 significant, clinically meaningful evidence of greater joint health concerns later in life, comparable

  17. Life Satisfaction, Self-Esteem, and Subjective Age in Women across the Life Span

    Science.gov (United States)

    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…

  18. Partner preferences across the life span: online dating by older adults.

    Science.gov (United States)

    Alterovitz, Sheyna Sears-Roberts; Mendelsohn, Gerald A

    2009-06-01

    Stereotypes of older adults as withdrawn or asexual fail to recognize that romantic relationships in later life are increasingly common. The authors analyzed 600 Internet personal ads from 4 age groups: 20-34, 40-54, 60-74, and 75+ years. Predictions from evolutionary theory held true in later life, when reproduction is no longer a concern. Across the life span, men sought physical attractiveness and offered status-related information more than women; women were more selective than men and sought status more than men. With age, men desired women increasingly younger than themselves, whereas women desired older men until ages 75 and over, when they sought men younger than themselves. (c) 2009 APA, all rights reserved.

  19. The Stationary-Phase Cells of Saccharomyces cerevisiae Display Dynamic Actin Filaments Required for Processes Extending Chronological Life Span

    Czech Academy of Sciences Publication Activity Database

    Vašicová, Pavla; Lejsková, Renata; Malcová, Ivana; Hašek, Jiří

    2015-01-01

    Roč. 35, č. 22 (2015), s. 3892-3908 ISSN 0270-7306 R&D Projects: GA ČR GAP305/12/0480 Institutional support: RVO:61388971 Keywords : MITOCHONDRIAL GENE-EXPRESSION * BUDDING YEAST * CALORIE RESTRICTION Subject RIV: CE - Biochemistry Impact factor: 4.427, year: 2015

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  2. Life span and tumorigenesis in mice exposed to continuous low dose-rate gamma-rays

    International Nuclear Information System (INIS)

    Tanaka, Satoshi; Braga-Tanaka III, Ignacia; Takabatake, Takashi; Ichinohe, Kazuaki; Tanaka, Kimio; Matsumoto, Tsuneya; Sato, Fumiaki

    2004-01-01

    Two experiments were conducted to evaluate late biological effects of chronic low dose-rate radiation. 1: Late effects of chronic low dose-rate gamma-ray irradiation on SPF mice, using life span and pathological changes as parameters. Continuous irradiation for approximately 400 days was performed using 137 Cs gamma-rays at dose-rates of 20 mGy/day, 1 mGy/day and 0.05 mGy/day with accumulated doses equivalent to 8000 mGy, 400 mGy and 20 mGy, respectively. All mice were kept until their natural death. Statistical analyses show that the life spans of the both sexes irradiated at 20 mGy/day (p<0.0001) and of females irradiated at 1 mGy/day (p<0.05) were significantly shorter than those of the control group. There was no evidence of lengthened life span in mice continuously exposed to very low dose-rates of gama-rays. Pathodological examinations showed that the most frequently observed lethal neoplasms in males were malignant lymphomas, liver, lung, and soft tissue neoplasms, whereas, in females, malignant lymphomas and soft tissue neoplasms were common. No significant difference in the causes of death and mortality rates between groups. Hematopoietic neoplasms (malignant lymphoma and myeloid leukemia), liver, lung and soft tissue neoplasms, showed a tendency to appear at a younger age in both sexes irradiated at 20 mGy/day. Experiment 2: effects on the progeny of chronic low dose-rate gamma-ray irradiated SPF mice: preliminary study. No significant difference was observed between non-irradiated group and irradiated group with regards to litter size, sex ratio and causes of death in F1 and F2 mice. (author)

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  5. Life-Span Development of Visual Working Memory: When is Feature Binding Difficult?

    OpenAIRE

    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 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 ...

  6. Life satisfaction, distress, and resiliency across the life span of women.

    Science.gov (United States)

    Beutel, Manfred E; Glaesmer, Heide; Decker, Oliver; Fischbeck, Sabine; Brähler, Elmar

    2009-01-01

    This study aimed to determine (1) the relationship between life satisfaction, mental disorders, and aging in the female community and (2) to identify the impact of vulnerability factors, personal (resilience, self-esteem), and social resources on life satisfaction and distress. A stratified random sample of the German female population (N = 2,540) was investigated using standardized questionnaires of life satisfaction (Questions on Life Satisfaction), depression, anxiety (Patient Health Questionnaire), resilience scale (RS-11), and self-esteem (Rosenberg Self-Esteem Scale). When participants were divided into six age groups (18-30, 31-40, 41-50, 51-60, 61-70, and >70 y), we found lower life satisfaction, satisfaction with partnership, and sexuality beyond the age of 50 years. Satisfaction with health was decreased already at early adulthood. Although the importance of partnership/sexuality was reduced around midlife, the importance of health increased. Depression was highest in the oldest group, whereas anxiety remained fairly stable across the cohorts. Life satisfaction was strongly associated with resilience, a good household income, the presence of a partnership, absence of anxiety and depression, lack of unemployment, positive self-esteem, religious affiliation, and-least-age. Personal and social resources and the absence of anxiety and depression are of crucial importance for the maintenance of life satisfaction in aging women.

  7. Vasoprotective effects of life span-extending peripubertal GH replacement in Lewis dwarf rats.

    Science.gov (United States)

    Ungvari, Zoltan; Gautam, Tripti; Koncz, Peter; Henthorn, Jim C; Pinto, John T; Ballabh, Praveen; Yan, Han; Mitschelen, Matthew; Farley, Julie; Sonntag, William E; Csiszar, Anna

    2010-11-01

    In humans, growth hormone deficiency (GHD) and low circulating levels of insulin-like growth factor 1 (IGF-1) significantly increase the risk for cerebrovascular disease. Genetic growth hormone (GH)/IGF-1 deficiency in Lewis dwarf rats significantly increases the incidence of late-life strokes, similar to the effects of GHD in elderly humans. Peripubertal treatment of Lewis dwarf rats with GH delays the occurrence of late-life stroke, which results in a significant extension of life span. The present study was designed to characterize the vascular effects of life span-extending peripubertal GH replacement in Lewis dwarf rats. Here, we report, based on measurements of dihydroethidium fluorescence, tissue isoprostane, GSH, and ascorbate content, that peripubertal GH/IGF-1 deficiency in Lewis dwarf rats increases vascular oxidative stress, which is prevented by GH replacement. Peripubertal GHD did not alter superoxide dismutase or catalase activities in the aorta nor the expression of Cu-Zn-SOD, Mn-SOD, and catalase in the cerebral arteries of dwarf rats. In contrast, cerebrovascular expression of glutathione peroxidase 1 was significantly decreased in dwarf vessels, and this effect was reversed by GH treatment. Peripubertal GHD significantly decreases expression of the Nrf2 target genes NQO1 and GCLC in the cerebral arteries, whereas it does not affect expression and activity of endothelial nitric oxide synthase and vascular expression of IGF-1, IGF-binding proteins, and inflammatory markers (tumor necrosis factor alpha, interluekin-6, interluekin-1β, inducible nitric oxide synthase, intercellular adhesion molecule 1, and monocyte chemotactic protein-1). In conclusion, peripubertal GH/IGF-1 deficiency confers pro-oxidative cellular effects, which likely promote an adverse functional and structural phenotype in the vasculature, and results in accelerated vascular impairments later in life.

  8. Life satisfaction, anxiety, depression and resilience across the life span of men.

    Science.gov (United States)

    Beutel, Manfred E; Glaesmer, Heide; Wiltink, Jörg; Marian, Hanna; Brähler, Elmar

    2010-03-01

    To determine (a) the relationship between life satisfaction, anxiety, depression and ageing in the male community and (b) to identify the impact of vulnerability factors, personal and social resources on life satisfaction and distress. A stratified random sample of the German male population (N = 2144) was investigated by standardized questionnaires of life satisfaction (FLZ(M)), depression, anxiety (PHQ), resilience (RS-11) and self-esteem (RSS). No age-related change was found regarding overall life satisfaction. Satisfaction with health decreased in midlife (51-60 years), while the importance of health increased. Importance of and satisfaction with partnership and sexuality were only reduced in the oldest group (70+). Anxiety was highest around midlife (51-60 years), accompanied by reduced resilience and self-esteem. No clear age-related change was found regarding depression. Life satisfaction was strongly associated with resilience, lack of unemployment, the presence of a partnership, positive self-esteem, a good household income, the absence of anxiety and depression and living in the Eastern states. Personal and social resources and the absence of anxiety and depression are of crucial importance for the maintenance of life satisfaction in ageing men. There is also evidence for a crisis around midlife manifested by health concerns, anxiety and reduced resilience.

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

    Science.gov (United States)

    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).

  10. Effects of low dose rate irradiation on life span prolongation of human premature-aging syndrome model mice

    International Nuclear Information System (INIS)

    Nomura, Takaharu

    2006-01-01

    We previously showed that Type II diabetes model mice prolonged of their life span by life long low dose rate irradiation. We also found that antioxidant function in variety tissues of some strain of mice were enhancement after low dose/low dose rate irradiation. The prolongation of life span might depend on certain damaged level of reactive oxygen species. We thought the effect of the prolongation was due to the enhancement of the antioxidant activities after irradiation. We investigated whether the enhancement of antioxidant activities after low dose rate irradiation had an effect on life span prolongation. Four-week-old female human premature-aging syndrome model mice, kl/kl (klotho) mice, which the life span of this model mouse is about 65 days, were irradiated with gamma rays at 0.35, 0.70 or 1.2 mGy/hr. The 0.70 mGy/hr-irradiated group remarkably effected on the prolongation of their life span. Some mice of the group were extremely survived for about and more 100 days. Antioxidant activities in the irradiated groups were enhancement by low dose rate irradiation, however the dependence of the dose rates were not clearly difference. These results suggest that the antioxidant activities in this model mouse were enhanced by the low dose rate irradiation, and may make it possible to prolong the life span of this mouse. (author)

  11. Causes of decreased life expectancy over the life span in bipolar disorder.

    Science.gov (United States)

    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.

  12. Correlation between DNA repair of embryonic fibroblasts and different life span of 3 inbred mouse strains

    Energy Technology Data Exchange (ETDEWEB)

    Paffenholz, V.

    1978-02-01

    Primary mouse fibroblast cultures were established from 10 day old embryos of 3 inbred strains with a genetically determined different life expectancy. The capacity for unscheduled DNA synthesis following uv irradiation was studied in these cells at various passage levels of the in vitro ageing process. The mouse fibroblasts show considerable repair synthesis corresponding to the duration of exposure time. The capacity for induction of unscheduled DNA synthesis was different in the cells of each strain and correlated to the natural life span of the animal. In each case, however, the ability to perform repair synthesis was subjected to an age-associated decline, although semiconservative DNA synthesis and proliferative potential of the cell was not changed until the cultures entered phase III passages.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  16. DOE life-span radiation effects studies at Pacific Northwest Laboratory

    International Nuclear Information System (INIS)

    Thompson, R.C.; Cross, F.T.; Dagle, G.E.; Park, J.F.; Sanders, C.L.

    1986-01-01

    Major life-span radiation effects studies at Pacific Northwest Laboratory fall into three categories: (1) studies with beagle dogs exposed to plutonium compounds via a single inhalation; (2) studies with dogs and rats exposed chronically via inhalation to various combinations and concentrations of radon, radon daughters, and other components of uranium mine atmospheres; and (3) a study in which rats are exposed via single inhalation, in very large numbers, to very low concentrations of 239 PuO 2 . Exposure of beagles currently on study was initiated in 1970 with 239 PuO 2 , in 1973 with 238 PuO 2 , and in 1976 with 239 Pu(NO 3 ) 4 . These experiments involve more than 500 animals, many of them still alive. Experiments seeking to explain the increased incidence of lung cancer in uranium miners have been in progress since 1966. Present emphasis is on studies with rats, in an attempt to define dose-effect relationships at the lowest feasible radon-daughter exposure levels. Our very-low-level experiment with inhaled 239 PuO 2 in rats, with exposures still under way, includes 1000 rats in the control group and 1000 rats in the lowest-exposure group, where life-span lung doses of <5 rads are anticipated

  17. Neoplastic and life-span effects of chronic exposure to tritium. II. Rats exposed in utero

    International Nuclear Information System (INIS)

    Cahill, D.F.; Wright, J.F.; Godbold, J.H.; Ward, J.M.; Laskey, J.W.; Tompkins, E.A.

    1975-01-01

    A study was conducted to determine the effects on neoplasia incidence and life-span of exposure in utero to a major environmental radionuclide. Sprague-Dawley rats were continuously exposed to tritiated water (HTO) from conception through birth in doses of 0, 1, 10, 50, and 100 μCi HTO/ml body water. HTO administration was terminated at birth. Calculated cumulative doses during gestation were approximately 0, 6.6, 66, 330, and 660 rads of total body irradiation. Under these exposure conditions, the two highest doses resulted in sterile offspring. Animals surviving through 30 days postnatally were defined as the study population and observed until their deaths. Intrauterine exposures to doses up to 66 rads had no significant effects on either sex with respect to lifespan, overall neoplasia incidence, incidence rate, or onset of mammary fibroadenomas. Females exposed to 330 or 660 rads were sterile and had lower incidence rates of mammary fibroadenomas than did controls; at 660 rads females had a lower incidence of overall neoplasia and reduced mean lifespans. Sterile male offspring had reduced mean longevity after irradiation at 660 rads. Regardless of dose group, females had significantly higher incidences of neoplasia and longer life-spans than males

  18. Studies on the life span, reproduction, tissue biochemistry and diesel oil toxicity in the estuarine cladocera Diaphanosoma celebensis

    Digital Repository Service at National Institute of Oceanography (India)

    PrabhuKonkar, S.R.; Achuthankutty, C.T.

    , neonate production, tissue biochemistry and toxicity of diesel oil have been described in the paper. Variations were observed in the life span and rate of neonate production between individuals of the 1 st and 2 nd generations. Both were found...

  19. Causes of decreased life expectancy over the life span in bipolar disorder

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Vradi, Eleni; McIntyre, Roger S

    2015-01-01

    BACKGROUND: Accelerated aging has been proposed as a mechanism explaining the increased prevalence of comorbid general medical illnesses in bipolar disorder. AIMS: To test the hypothesis that lost life years due to natural causes starts in early and mid-adulthood, supporting the hypothesis...... of accelerated aging. METHODS: 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. RESULTS: 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...

  20. The effect of developmental nutrition on life span and fecundity depends on the adult reproductive environment in Drosophila melanogaster

    NARCIS (Netherlands)

    May, C.M.; Doroszuk, A.; Zwaan, B.J.

    2015-01-01

    Both developmental nutrition and adult nutrition affect life-history traits; however, little is known about whether the effect of developmental nutrition depends on the adult environment experienced. We used the fruit fly to determine whether life-history traits, particularly life span and

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  4. Significance of Building Maintenance Management on Life-Span of Buildings

    Directory of Open Access Journals (Sweden)

    Md Azree Othuman Mydin

    2017-06-01

    Full Text Available The attentions and skills of maintenance are required for the construction of buildings in this twenty-first century. Because much architectural education is still focused on the one-of-a-kind assignment, encouraging the notion of personal fulfillment through leaving a mark for off-springs and obtaining a design award by means of concept drawings. Due to the reason that many building designers (architects, engineers, technicians are not encompassed in the subsequent maintenance of the building, they just regard it as other specialists’ responsibilities. In all likelihood, the building user-to-be has no formal role: the building contractors just fulfill their accountabilities to complete the building in compliance with the contract documents, not to care occupier’s needs and wants. This paper will focus on the important of building maintenance management on the life-span of buildings.

  5. Life spans of a Bellman-Harris branching process with immigration

    International Nuclear Information System (INIS)

    Badalbaev, I.S.; Mashrabbaev, A.

    1987-01-01

    One considers two schemes of the Bellman-Harris process with immigration when a) the lifetime of the particles is an integral-valued random variable and the immigration is defined by a sequence of independent random variables; b) the distribution of the lifetime of the particles is nonlattice and the immigration is a process with continuous time. One investigates the properties of the life spans of such processes. The results obtained here are a generalization to the case of Bellman-Harris processes of the results of A.M. Zubkov, obtained for Markov branching processes. For the proof one makes use in an essential manner of the known inequalities of Goldstein, estimating the generating function of the Bellman-Harris process in terms of the generating functions of the imbedded Galton-Watson process

  6. Life Span Studies of ADHD-Conceptual Challenges and Predictors of Persistence and Outcome

    DEFF Research Database (Denmark)

    Caye, Arthur; Swanson, James; Thapar, Anita

    2016-01-01

    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...... 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....... 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...

  7. Compassionate Love for a Romantic Partner Across the Adult Life Span

    Science.gov (United States)

    Neto, Félix; Wilks, Daniela C.

    2017-01-01

    Compassionate love has received research attention over the last decade, but it is as yet unclear how it is experienced over a lifetime. The purpose of this study was to investigate compassionate love for a romantic partner throughout the adult life span, exploring individual differences in the propensity to experience compassionate love in regard to age, gender, religion, love status, love styles, and subjective well-being. The results showed that religion and love status display significant effects on compassionate love. Believers experienced greater compassionate love than nonbelievers, and individuals in love presented greater compassionate love than those who were not in love. Love styles and subjective well-being were found to be related to compassionate love. These findings corroborate studies that indicate that individuals who experience higher compassionate love for a romantic partner are more likely to report Eros, Agape, and subjective well-being. PMID:29358977

  8. Mice selectively bred for open-field thigmotaxis: life span and stability of the selection trait.

    Science.gov (United States)

    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.

  9. Virtual navigation strategies from childhood to senescence: evidence for changes across the life span

    Directory of Open Access Journals (Sweden)

    Veronique D Bohbot

    2012-11-01

    Full Text Available This study sought to investigate navigational strategies across the life span, by testing 8-year old children to 80-year old healthy older adults on the 4 on 8 virtual maze (4/8VM. The 4/8VM was previously developed to assess spontaneous navigational strategies, i.e. hippocampal-dependent spatial strategies (navigation by memorizing relationships between landmarks versus caudate nucleus-dependent response strategies (memorizing a series of left and right turns from a given starting position. With the 4/8VM, we previously demonstrated greater fMRI activity and grey matter in the hippocampus of spatial learners relative to response learners. A sample of 599 healthy participants was tested in the current study. Results showed that 84.4% of children, 46.3% of young adults, and 39.3% of older adults spontaneously used spatial strategies (p < 0.0001. Our results suggest that while children predominantly use spatial strategies, the proportion of participants using spatial strategies decreases across the life span, in favor of response strategies. Factors promoting response strategies include repetition, reward and stress. Since response strategies can result from successful repetition of a behavioral pattern, we propose that the increase in response strategies is a biological adaptive mechanism that allows for the automatization of behavior such as walking in order to free up hippocampal-dependent resources. However, the downside of this shift from spatial to response strategies occurs if people stop building novel relationships, which occurs with repetition and routine, and thereby stop stimulating their hippocampus. Reduced fMRI activity and grey matter in the hippocampus were shown to correlate with cognitive deficits in normal aging. Therefore, these results have important implications regarding factors involved in healthy and successful aging.

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

    Science.gov (United States)

    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.

  11. Age- and calorie-independent life span extension from dietary restriction by bacterial deprivation in Caenorhabditis elegans

    Directory of Open Access Journals (Sweden)

    Sager Jennifer

    2008-05-01

    Full Text Available Abstract Background Dietary restriction (DR increases life span and delays age-associated disease in many organisms. The mechanism by which DR enhances longevity is not well understood. Results Using bacterial food deprivation as a means of DR in C. elegans, we show that transient DR confers long-term benefits including stress resistance and increased longevity. Consistent with studies in the fruit fly and in mice, we demonstrate that DR also enhances survival when initiated late in life. DR by bacterial food deprivation significantly increases life span in worms when initiated as late as 24 days of adulthood, an age at which greater than 50% of the cohort have died. These survival benefits are, at least partially, independent of food consumption, as control fed animals are no longer consuming bacterial food at this advanced age. Animals separated from the bacterial lawn by a barrier of solid agar have a life span intermediate between control fed and food restricted animals. Thus, we find that life span extension from bacterial deprivation can be partially suppressed by a diffusible component of the bacterial food source, suggesting a calorie-independent mechanism for life span extension by dietary restriction. Conclusion Based on these findings, we propose that dietary restriction by bacterial deprivation increases longevity in C. elegans by a combination of reduced food consumption and decreased food sensing.

  12. Effect of gamma irradiation on the life span of Drosophila melanogaster (Demonstration of threshold and sexual sensitivity differences)

    International Nuclear Information System (INIS)

    Giess, M.-C.; Planel, H.

    1977-01-01

    Drosophila melanogaster is irradiated by 5 to 75 krads of 60 Co gamma radiation at a dose rate of 1,000 rads/mn, on the fourth day of its imaginal life. As a result, the life span of the flies is reduced for both sexes. However, females are more radiosensitive than males. On the other hand, the radiosensitivity threshold in females is lower than in males: a life span decrease starts in males at a dose of 10 krads and at a dose of 25 krads in females [fr

  13. Cancer risk among atomic bomb survivors. The RERF Life Span Study. Radiation Effects Research Foundation

    International Nuclear Information System (INIS)

    Shimizu, Y.; Schull, W.J.; Kato, H.

    1990-01-01

    This article summarizes the risk of cancer among the survivors of the atomic bombing of Hiroshima and Nagasaki. We focus primarily on the risk of death from cancer among individuals in the Life Span Study sample of the Radiation Effects Research Foundation from 1950 through 1985 based on recently revised dosimetry procedures. We report the risk of cancer other than leukemia among the atomic bomb survivors. We note that the number of excess deaths of radiation-induced malignant tumors other than leukemia increases with age. Survivors who were exposed in the first or second decade of life have just entered the cancer-prone age and have so far exhibited a high relative risk in association with radiation dose. Whether the elevated risk will continue or will fall with time is not yet clear, although some evidence suggests that the risk may be declining. It is important to continue long-term follow-up of this cohort to document the changes with time since exposure and to provide direct rather than projected risks over the lifetime of an exposed individual

  14. Radiation effects on cancer risks in the life span study cohort

    International Nuclear Information System (INIS)

    Kodama, K.; Ozasa, K.; Katayama, H.; Shore, R. E.; Okubo, T.

    2012-01-01

    To determine late health effects of radiation in atomic bomb survivors, the Radiation Effects Research Foundation has been conducting studies on the Life Span Study (LSS) population, which consists of 93 000 atomic bomb survivors and 27.000 controls. A recent report on the incidence of solid cancers estimates that at the age of 70 y, after exposure at the age of 30 y, solid-cancer rates increase by about 35 % per Gy for men and 58 % per Gy for women. The age-at-exposure is an important risk modifier. Furthermore, it seems that radiation-associated increases in cancer rates persist throughout life. In addition, radiation has similar effects upon first-primary and second-primary cancer risks. A recent report on leukemia mortality suggested that the effect of radiation on leukemia mortality persisted for more than five decades. In addition, a significant dose-response for myelodysplastic syndrome is found in Nagasaki LSS members 40-60 y after radiation exposure. In view of the nature of the continuing increase in solid cancers, the LSS should continue to provide important new information on cancer risks, as most survivors still alive today were exposed to the atomic bomb radiation under the age of 20 y and are now entering their cancer-prone years. (authors)

  15. Chips in black boxes? Convenience life span, parafood, brandwidth, families, and co-creation.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  17. A major QTL affects temperature sensitive adult lethality and inbreeding depression in life span in Drosophila melanogaster.

    DEFF Research Database (Denmark)

    Vermeulen, Corneel J.; Bijlsma, R.; Loeschcke, Volker

    2008-01-01

    of inbreeding effects in specific traits, such as age-specific mortality and life span, provide a good starting point, as a limited set of genes is expected to be involved. Results Here we report on a QTL mapping study on inbreeding related and temperature sensitive lethality in male Drosophila melanogaster...... and the molecular properties of genes that give rise to or modulate its deleterious effects is lacking. These questions warrant the detailed study of genetic loci giving rise to inbreeding depression. However, the complex and polygenic nature of general inbreeding depression makes this a daunting task. Study...... simple, being due mainly to a single recessive QTL on the left arm of chromosome 2. This locus colocalised with a QTL that conditioned variation in female life span, acting as an overdominant locus for this trait. Male life span was additionally affected by variation at the X-chromosome. Conclusion...

  18. Mortality pattern and life span in case of combined effect of incorporated radioisotopes, smoking and ethanol in the experiment

    International Nuclear Information System (INIS)

    Kupriyanova, V.M.

    1988-01-01

    It is established that life span and mortality pattern of animals subjected to chronic intake of 90 Sr, to the effect of ethanol, and smoking depend on the intensity of radiation and radiation doses, character of harmful factors, age and sex dependences. The mean life span of animals subjected to the combined effect of 90 Sr(10 -3 LD50/30) of ethanol and smoking was by 18-22 % lower in comparison with intact animals. Alongside with the mean life span decrease latent period of carcinogenesis is shortened. A high tendency to metastases formation was noted in case of combined action of these factors than in comparison with isolated effect of them. 3 refs.; 1 tab

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

    Science.gov (United States)

    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

  20. Measuring the genetic influence on human life span: gene-environment interaction and sex-specific genetic effects

    DEFF Research Database (Denmark)

    Tan, Qihua; De Benedictis, G; Yashin, Annatoli

    2001-01-01

    New approaches are needed to explore the different ways in which genes affect the human life span. One needs to assess the genetic effects themselves, as well as gene–environment interactions and sex dependency. In this paper, we present a new model that combines both genotypic and demographicinf......New approaches are needed to explore the different ways in which genes affect the human life span. One needs to assess the genetic effects themselves, as well as gene–environment interactions and sex dependency. In this paper, we present a new model that combines both genotypic...

  1. Determination of life-span reserve of main steam ducts in thermal power plants

    International Nuclear Information System (INIS)

    Demian, Mihai; Trusculescu, Marin;

    2002-01-01

    The safe operation of the active vapour ducts requires periodic inspections of the structural conditions and of the properties of the used materials. There are possibilities to establish the structural evolution and that of the materials' properties through destructive or non - destructive methods. Currently, we mostly employ destructive methods by which we can establish the microstructure of the material and the mechanical properties at the temperature of operation for certain periods of time. Lately, we employ non-destructive methods of approaching the structural evolution as a function of operation temperature and work duration. The paper presents the determination of the reserve of the life span of a duct with a 426 mm diameter and 16 mm thickness, which works for 84,556 hours at a temperature of 540 deg. C and a pressure of 2.44 MPa within a thermo - electric power station. By creep trials we established that this duct could also be operated for 16,000 - 28,000 hours. Using the Struers replicas and establishing the 'A' parameter of the degradation of the microstructure in time, we determined a maximum duration of safe exploitation of this duct, of 16,065 hours. Although the non - destructive method is less laborious and does not require sampling from the ducts, it should be adjusted with moderation until there is perfected the methodology of the establishment of the degradation of the grains limits. We recommend that the non - destructive method be available in order to be employed currently with informative character. (authors)

  2. Leukemia incidence in the atomic bomb survivor Life Span Study, 1950 - 87

    International Nuclear Information System (INIS)

    Preston, D.L.; Mabuchi, K.; Kusumi, S.; Izumi, S.

    1992-01-01

    The Radiation Effects Research Foundation (RERF) is currently preparing a series of reports on cancer incidence in the Life Span Study (LSS) cohort of atomic bomb survivors for the period from 1950 to 1987. One of these reports will present analyses of the data on the risk of hematopoietic cancers including leukemia, malignant lymphoma, and multiple myeloma. These analyses add an additional 11 years of follow-up to the previous comprehensive analysis of the LSS leukemia data. In this presentation, these data are presented and the methods being used modeling the leukemia risks are outlined. An analysis of the leukemia data pooled over subtypes will be used to illustrate these methods. It is shown that the data suggest a non-linear, concave upward dose response and that the temporal pattern of the radiation-induced excess absolute risks (EARs) depends on age-at-exposure and sex. There is no evidence of city differences in the EAR in this pooled analysis. The results suggest that the EARs for the youngest survivors were initially much higher and have declined more rapidly than those for older survivors. The same general pattern is seen both sexes, but the initial peak incidence is somewhat lower and the rate of decline less rapid for women than for men. (author)

  3. Childhood self-control and unemployment throughout the life span: evidence from two British cohort studies.

    Science.gov (United States)

    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.

  4. Life Span Studies of ADHD—Conceptual Challenges and Predictors of Persistence and Outcome

    Science.gov (United States)

    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

  5. The Development of Regional Dialect Locality Judgments and Language Attitudes Across the Life Span.

    Science.gov (United States)

    McCullough, Elizabeth A; Clopper, Cynthia G; Wagner, Laura

    2017-10-20

    The development of language attitudes and perception of talker regional background was investigated across the life span (N = 240, age range = 4-75 years). Participants rated 12 talkers on dimensions of geographic locality, status, and solidarity. Children could classify some dialects by locality by age 6-7 years and showed adult-like patterns by age 8 years. Children showed adult-like status ratings for some dialects by age 4-5 years but were not fully adult-like until age 12 years. Solidarity ratings were more variable and did not exhibit a clear developmental trajectory, although some adult-like patterns were in place by age 6-7 years. Locality ratings were a significant but modest predictor of attitude ratings, suggesting that geographic knowledge is one contributor to language attitudes throughout development. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

  6. Object-based encoding in visual working memory: a life span study.

    Science.gov (United States)

    Zhang, Qiong; Shen, Mowei; Tang, Ning; Zhao, Guohua; Gao, Zaifeng

    2013-08-20

    Recent studies on development of visual working memory (VWM) predominantly focus on VWM capacity and spatial-based information filtering in VWM. Here we explored another new aspect of VWM development: object-based encoding (OBE), which refers to the fact that even if one feature dimension is required to be selected into VWM, the other irrelevant dimensions are also extracted. We explored the OBE in children, young adults, and old adults, by probing an "irrelevant-change distracting effect" in which a change of stored irrelevant feature dramatically affects the performance of task-relevant features in a change-detection task. Participants were required to remember two or four simple colored shapes, while color was used as the relevant dimension. We found that changes to irrelevant shapes led to a significant distracting effect across the three age groups in both load conditions; however, children showed a greater degree of OBE than did young and old adults. These results suggest that OBE exists in VWM over the life span (6-67 years), yet continues to develop along with VWM.

  7. Mixed emotions across the adult life span in the United States

    Science.gov (United States)

    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

  8. Evaluative ratings and attention across the life span: emotional arousal and gender.

    Science.gov (United States)

    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.

  9. Tracking the trajectory of shame, guilt, and pride across the life span.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  11. Dietary Intake of Curcuma longa and Emblica officinalis Increases Life Span in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Shilpa Rawal

    2014-01-01

    Full Text Available 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.

  12. Effects of x-irradiation of young female beagles on life span and tumor incidence

    International Nuclear Information System (INIS)

    Rosenblatt, L.S.; Book, S.A.; Goldman, M.

    1986-01-01

    Causes of death and the occurrence of neoplasia in female beagle dogs were evaluated retrospectively for 57 unexposed and 296 exposed dogs given single or fractionated whole-body x-irradiation exposures of 100 or 300 R. Some dogs subsequently were bred, and all were observed for the duration of their lives. The pathology for these dogs was derived from clinical records, gross-necropsy reports, tissue slides, and Formalin-fixed tissues. The results of this study indicated dose-related shortening of life span was clearly evident; causes of death due to either neoplasia (50%) or nonneoplastic disease (50%), with few exceptions, were similar in control and irradiated dogs; the incidences of neoplasms were not significantly greater for irradiated dogs than for controls, but the latency period decreased as dose increased; protraction increased survival in dogs given 300 R but not 100 R, which is attributable solely to amelioration of incidence rates of nonmammary neoplasia; and the cumulative rates of death due to mammary tumors were the same in dogs exposed to 100 R and 300 R. 14 refs., 6 figs., 2 tabs

  13. Eyewitness identification across the life span: A meta-analysis of age differences.

    Science.gov (United States)

    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).

  14. General Slowing and Education Mediate Task Switching Performance Across the Life-Span

    Directory of Open Access Journals (Sweden)

    Luca Moretti

    2018-05-01

    Full Text Available 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.

  15. Individual Differences in Behavioral and Electrophysiological Measures of Binaural Processing Across the Adult Life Span.

    Science.gov (United States)

    Roup, Christina M; Leigh, Elizabeth D

    2015-06-01

    The purpose of the present study was to examine individual differences in binaural processing across the adult life span. Sixty listeners (aged 23-80 years) with symmetrical hearing were tested. Binaural behavioral processing was measured by the Words-in-Noise Test, the 500-Hz masking level difference, and the Dichotic Digit Test. Electrophysiologic responses were assessed by the auditory middle latency response binaural interaction component. No correlations among binaural measures were found. Age accounted for the greatest amount of variability in speech-in-noise performance. Age was significantly correlated with the Words-in-Noise Test binaural advantage and dichotic ear advantage. Partial correlations, however, revealed that this was an effect of hearing status rather than age per se. Inspection of individual results revealed that 20% of listeners demonstrated reduced binaural performance for at least 2 of the binaural measures. The lack of significant correlations among variables suggests that each is an important measurement of binaural abilities. For some listeners, binaural processing was abnormal, reflecting a binaural processing deficit not identified by monaural audiologic tests. The inclusion of a binaural test battery in the audiologic evaluation is supported given that these listeners may benefit from alternative forms of audiologic rehabilitation.

  16. Retention of high tactile acuity throughout the life span in blindness.

    Science.gov (United States)

    Legge, Gordon E; Madison, Cindee; Vaughn, Brenna N; Cheong, Allen M Y; Miller, Joseph C

    2008-11-01

    Previous studies of tactile acuity on the fingertip, using passive touch, have demonstrated an age-related decline in spatial resolution for both sighted and blind subjects. We have reexamined this age dependence with two newly designed tactile-acuity charts that require active exploration of the test symbols. One chart used dot patterns similar to braille, and the other used embossed Landolt rings. Groups of blind braille readers and sighted subjects ranging from 12 to 85 years old were tested in two experiments. We replicated previous findings for sighted subjects by showing an age-related decrease in tactile acuity by nearly 1% per year. Surprisingly, the blind subjects retained high acuity into old age, showing no age-related decline. For the blind subjects, tactile acuity did not correlate with braille reading speed, the amount of daily reading, or the age at which braille was learned. We conclude that when measured with active touch, blind subjects retain high tactile acuity into old age, unlike their aging sighted peers. We propose that blind people's use of active touch in daily activities, not specifically braille reading, results in preservation of tactile acuity across the life span.

  17. [Intention for self-change across the life span: Focusing on concern about self-change].

    Science.gov (United States)

    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.

  18. Age Differences in Explicit and Implicit Age Attitudes Across the Life Span.

    Science.gov (United States)

    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.

  19. A Fasting-Responsive Signaling Pathway that Extends Life Span in C. elegans

    Directory of Open Access Journals (Sweden)

    Masaharu Uno

    2013-01-01

    Full Text Available Intermittent fasting is one of the most effective dietary restriction regimens that extend life span in C. elegans and mammals. Fasting-stimulus responses are key to the longevity response; however, the mechanisms that sense and transduce the fasting stimulus remain largely unknown. Through a comprehensive transcriptome analysis in C. elegans, we find that along with the FOXO transcription factor DAF-16, AP-1 (JUN-1/FOS-1 plays a central role in fasting-induced transcriptional changes. KGB-1, one of the C. elegans JNKs, acts as an activator of AP-1 and is activated in response to fasting. KGB-1 and AP-1 are involved in intermittent fasting-induced longevity. Fasting-induced upregulation of the components of the SCF E3 ubiquitin ligase complex via AP-1 and DAF-16 enhances protein ubiquitination and reduces protein carbonylation. Our results thus identify a fasting-responsive KGB-1/AP-1 signaling pathway, which, together with DAF-16, causes transcriptional changes that mediate longevity, partly through regulating proteostasis.

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

    Science.gov (United States)

    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.

  1. Multimodal neuroimaging of male and female brain structure in health and disease across the life span.

    Science.gov (United States)

    Jahanshad, Neda; Thompson, Paul M

    2017-01-02

    Sex differences in brain development and aging are important to identify, as they may help to understand risk factors and outcomes in brain disorders that are more prevalent in one sex compared with the other. Brain imaging techniques have advanced rapidly in recent years, yielding detailed structural and functional maps of the living brain. Even so, studies are often limited in sample size, and inconsistent findings emerge, one example being varying findings regarding sex differences in the size of the corpus callosum. More recently, large-scale neuroimaging consortia such as the Enhancing Neuro Imaging Genetics through Meta Analysis Consortium have formed, pooling together expertise, data, and resources from hundreds of institutions around the world to ensure adequate power and reproducibility. These initiatives are helping us to better understand how brain structure is affected by development, disease, and potential modulators of these effects, including sex. This review highlights some established and disputed sex differences in brain structure across the life span, as well as pitfalls related to interpreting sex differences in health and disease. We also describe sex-related findings from the ENIGMA consortium, and ongoing efforts to better understand sex differences in brain circuitry. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc.

  2. β-N-methylamino-L-alanine induces neurological deficits and shortened life span in Drosophila.

    Science.gov (United States)

    Zhou, Xianchong; Escala, Wilfredo; Papapetropoulos, Spyridon; Zhai, R Grace

    2010-11-01

    The neurotoxic non-protein amino acid, β-N-methylamino-L-alanine (BMAA), was first associated with the high incidence of Amyotrophic Lateral Sclerosis/Parkinsonism Dementia Complex (ALS/PDC) in Guam. Recently, BMAA has been implicated as a fierce environmental factor that contributes to the etiology of Alzheimer's and Parkinson's diseases, in addition to ALS. However, the toxicity of BMAA in vivo has not been clearly demonstrated. Here we report our investigation of the neurotoxicity of BMAA in Drosophila. We found that dietary intake of BMAA reduced life span, locomotor functions, and learning and memory abilities in flies. The severity of the alterations in phenotype is correlated with the concentration of BMAA detected in flies. Interestingly, developmental exposure to BMAA had limited impact on survival rate, but reduced fertility in females, and caused delayed neurological impairment in aged adults. Our studies indicate that BMAA exposure causes chronic neurotoxicity, and that Drosophila serves as a useful model in dissecting the pathogenesis of ALS/PDC.

  3. Effects of kaolin particle films on the life span of an orb-weaver spider.

    Science.gov (United States)

    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.

  4. Oxidative stress and the evolution of sex differences in life span and ageing in the decorated cricket, Gryllodes sigillatus.

    Science.gov (United States)

    Archer, Catharine R; Sakaluk, Scott K; Selman, Colin; Royle, Nick J; Hunt, John

    2013-03-01

    The Free Radical Theory of Ageing (FRTA) predicts that oxidative stress, induced when levels of reactive oxygen species exceed the capacity of antioxidant defenses, causes ageing. Recently, it has also been argued that oxidative damage may mediate important life-history trade-offs. Here, we use inbred lines of the decorated cricket, Gryllodes sigillatus, to estimate the genetic (co)variance between age-dependent reproductive effort, life span, ageing, oxidative damage, and total antioxidant capacity within and between the sexes. The FRTA predicts that oxidative damage should accumulate with age and negatively correlate with life span. We find that protein oxidation is greater in the shorter lived sex (females) and negatively genetically correlated with life span in both sexes. However, oxidative damage did not accumulate with age in either sex. Previously we have shown antagonistic pleiotropy between the genes for early-life reproductive effort and ageing rate in both sexes, although this was stronger in females. In females, we find that elevated fecundity early in life is associated with greater protein oxidation later in life, which is in turn positively correlated with the rate of ageing. Our results provide mixed support for the FRTA but suggest that oxidative stress may mediate sex-specific life-history strategies in G. sigillatus. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  5. The influence of sensorimotor experience on the aesthetic evaluation of dance across the life span.

    Science.gov (United States)

    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.

  6. Biological Aging and Life Span Based on Entropy Stress via Organ and Mitochondrial Metabolic Loading

    Directory of Open Access Journals (Sweden)

    Kalyan Annamalai

    2017-10-01

    Full Text Available The energy for sustaining life is released through the oxidation of glucose, fats, and proteins. A part of the energy released within each cell is stored as chemical energy of Adenosine Tri-Phosphate molecules, which is essential for performing life-sustaining functions, while the remainder is released as heat in order to maintain isothermal state of the body. Earlier literature introduced the availability concepts from thermodynamics, related the specific irreversibility and entropy generation rates to metabolic efficiency and energy release rate of organ k, computed whole body specific entropy generation rate of whole body at any given age as a sum of entropy generation within four vital organs Brain, Heart, Kidney, Liver (BHKL with 5th organ being the rest of organs (R5 and estimated the life span using an upper limit on lifetime entropy generated per unit mass of body, σM,life. The organ entropy stress expressed in terms of lifetime specific entropy generated per unit mass of body organs (kJ/(K kg of organ k was used to rank organs and heart ranked highest while liver ranked lowest. The present work includes the effects of (1 two additional organs: adipose tissue (AT and skeletal muscles (SM which are of importance to athletes; (2 proportions of nutrients oxidized which affects blood temperature and metabolic efficiencies; (3 conversion of the entropy stress from organ/cellular level to mitochondrial level; and (4 use these parameters as metabolism-based biomarkers for quantifying the biological aging process in reaching the limit of σM,life. Based on the 7-organ model and Elia constants for organ metabolic rates for a male of 84 kg steady mass and using basic and derived allometric constants of organs, the lifetime energy expenditure is estimated to be 2725 MJ/kg body mass while lifetime entropy generated is 6050 kJ/(K kg body mass with contributions of 190; 1835.0; 610; 290; 700; 1470 and 95 kJ/K contributed by AT-BHKL-SM-R7 to 1 kg body

  7. What about time? : Examining chronological and subjective age and their relation to work motivation.

    NARCIS (Netherlands)

    Akkermans,; De Lange,; Van der Heijden,; Kooij, T.A.M.; Jansen,; Dikkers,

    2016-01-01

    Purpose The aging workforce is becoming an increasingly important topic in today’s labor market. However, most scientific research and organizational policies focus on chronological age as the main determinant of successful aging. Based on life span developmental theories – primarily socioemotional

  8. What about time? Examining chronological and subjective age and their relation to work motivation

    NARCIS (Netherlands)

    Akkermans, J.; Lange, A.H. de; Heijden, B.I.J.M. van der; Kooij, D.T.A.M.; Jansen, P.G.W.; Dikkers, J.S.E.

    2016-01-01

    PURPOSE - The aging workforce is becoming an increasingly important topic in today’s labor market. However, most scientific research and organizational policies focus on chronological age as the main determinant of successful aging. Based on life span developmental theories – primarily

  9. What about Time? Examining Chronological and Subjective Age and their Relation to Work Motivation

    NARCIS (Netherlands)

    Akkermans, J.; de Lange, A.H.; Van der Heijden, B.I.J.M.; Kooij, T.A.M.; Jansen, P.G.W.; Dikkers, J.

    2016-01-01

    Purpose: The aging workforce is becoming an increasingly important topic in today’s labor market. However, most scientific research and organizational policies focus on chronological age as the main determinant of successful aging. Based on life span developmental theories – primarily socioemotional

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

    Science.gov (United States)

    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.

  11. Proteomic profiles reveal age-related changes in coelomic fluid of sea urchin species with different life spans.

    Science.gov (United States)

    Bodnar, Andrea

    2013-05-01

    Sea urchins have a different life history from humans and traditional model organisms used to study the process of aging. Sea urchins grow indeterminately, reproduce throughout their life span and some species have been shown to exhibit negligible senescence with no increase in mortality rate at advanced ages. Despite these properties, different species of sea urchins are reported to have very different natural life spans providing a unique model to investigate cellular mechanisms underlying life span determination and negligible senescence. To gain insight into the biological changes that accompany aging in these animals, proteomic profiles were examined in coelomic fluid from young and old sea urchins of three species with different life spans: short-lived Lytechinus variegatus, long-lived Strongylocentrotus franciscanus and Strongylocentrotus purpuratus which has an intermediate life span. The proteomic profiles of cell-free coelomic fluid were complex with many proteins exhibiting different forms and extensive post-translational modifications. Approximately 20% of the protein spots on 2-D gels showed more than two-fold change with age in each of the species. Changes that are consistent with age in all three species may prove to be useful biomarkers for age-determination for these commercially fished marine invertebrates and also may provide clues to mechanisms of negligible senescence. Among the proteins that change with age, the ectodomain of low-density lipoprotein receptor-related protein 4 (LRP4) was significantly increased in the coelomic fluid of all three sea urchin species suggesting that the Wnt signaling pathway should be further investigated for its role in negligible senescence. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. JNIH-ABCC Life Span Study, Hiroshima 1950-59. Multiple causes of death stated in medical certificates

    Energy Technology Data Exchange (ETDEWEB)

    Ishida, Morihiro; Jablon, S

    1962-08-22

    The applicability to the JNIH-ABCC Life Span Study of secondary causes shown in Hiroshima death certificates is discussed. The analysis is based on 5526 death certificates reported among members of Selection I and II of the Life Span Study sample. Secondary causes appear to be of only limited usefulness to the Life Span Study. Factors such as age, sex, exposure status, which may influence the frequency of entry of secondary causes in medical certificates are analyzed. Age is the only factor which shows a significant relationship and this may be interpreted as resulting from the fact that chronic diseases with multiple illnesses are most prevalent among persons at older ages. The number of secondary causes in the present study is too small to delineate in detail the pattern of complications or contributory causes. However, 9 cases of malignant neoplasms were entered only as complications and were missed in the primary tabulation, representing only about one percent of all malignancies. Secondary causes shown in the death certificates and associated causes found at postmortem examination seem not to be comparably distributed, thus raising a serious problem as to the applicability of the former to the Life Span Study. Both the magnitude and accuracy of entry of the secondary causes are influenced greatly by the ease with which illnesses may be detected clinically. 9 references, 12 tables.

  13. Dispersal and life span spectra in plant communities : a key to safe site dynamics, species coexistence and conservation

    NARCIS (Netherlands)

    Strykstra, RJ; Bekker, RM; Van Andel, J

    Dispersal and life span of individual plant species within five plant communities were assessed to obtain a characterization of these communities in this respect. Such a characterization is important in the context of restoration and maintenance. The most frequent species of five communities were

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

    Science.gov (United States)

    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.

  15. Long will they live, work and learn : A scheme for understanding and influencing employability during the life span

    NARCIS (Netherlands)

    Nauta, Aukje; de Lange, Annet H.; Gortz, Saskia

    2010-01-01

    Long will they live, work and learn. A scheme for understanding and influencing employability during the life span A. Nauta, A. H. de Lange en S. Gortz, Gedrag & Organisatie, volume 23, June 2010, nr. 2, pp. 136-157 To stimulate employees' employability until high age, knowledge is needed about what

  16. Age at menopause, reproductive life span, and type 2 diabetes risk results from the EPIC-interAct Study

    NARCIS (Netherlands)

    Brand, J.S.; Schouw, van der Y.T.; Onland-Moret, N.; Sharp, S.J.; Feskens, E.J.M.

    2013-01-01

    OBJECTIVEAge at menopause is an important determinant of future health outcomes, but little is known about its relationship with type 2 diabetes. We examined the associations of menopausal age and reproductive life span (menopausal age minus menarcheal age) with diabetes risk.RESEARCH DESIGN AND

  17. Use of linear model analysis techniques in the evaluation of radiation effects on the life span of the beagle

    International Nuclear Information System (INIS)

    Angleton, G.M.; Lee, A.C.; Benjamin, S.A.

    1986-01-01

    The dependency of the beagle-dog life span on level of and age at exposure to 60 Co gamma radiation was analyzed by several techniques; one of these methods was linear model analysis. Beagles of both sexes were given single, bilateral exposures at 8, 28, or 55 days postcoitus (dpc) or at 2, 70, or 365 days postpartum (dpp). Dogs exposed at 8, 28, or 55 dpc or at 2 dpp received 0, 20, or 100 R, whereas those exposed at 70 or 365 dpp received 0 or 100 R. Beagles were designated initially either as sacrifice or as life-span animals. All deaths of life-span study animals were classified as spontaneous, hence for this group the mean age of death was a quantitative response that can be analyzed by linear model analysis techniques. Such analyses for each age group were performed, taking into account differences due to sex, linear and quadratic dependency on dose, and interaction between sex and dose. At this time most of the animals have reached 11 years of age. No significant effects of radiation on mean life span have been detected. 6 refs., 3 figs., 3 tabs

  18. Global quantification of contrasting leaf life span strategies for deciduous and evergreen species in response to environmental conditions.

    NARCIS (Netherlands)

    van Ommen Kloeke, A.E.E.; Douma, J.C.; Ordonez Barragan, J.C.; Reick, P.B.; van Bodegom, P.M.

    2012-01-01

    Aim Species with deciduous and evergreen leaf habits typically differ in leaf life span (LLS). Yet quantification of the response of LLS, within each habit, to key environmental conditions is surprisingly lacking. The aim of this study is to quantify LLS strategies of the two leaf habits under

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

    Science.gov (United States)

    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…

  20. Families enriched for exceptional longevity also have increased health span: Findings from the Long Life Family Study

    Directory of Open Access Journals (Sweden)

    Paola eSebastiani

    2013-09-01

    Full Text Available Hypothesizing that members of families enriched for longevity delay morbidity compared to population controls and approximate the health-span of centenarians, we compared the health spans of older generation subjects of the Long Life Family Study (LLFS to controls without family history of longevity and to centenarians of the New England Centenarian Study (NECS using Bayesian parametric survival analysis. We estimated hazard ratios, the ages at which specific percentiles of subjects had onsets of diseases, and the gain of years of disease-free survival in the different cohorts compared to referent controls. Compared to controls, LLFS subjects had lower hazards for cancer, cardiovascular disease, severe dementia, diabetes, hypertension, osteoporosis and stroke. The age at which 20% of the LLFS siblings and probands had one or more age-related diseases was approximately 10 years later than NECS controls. While female NECS controls generally delayed the onset of age-related diseases compared with males controls, these gender differences became much less in the older generation of the LLFS and disappeared amongst the centenarians of the NECS. The analyses demonstrate extended health-span in the older subjects of the LLFS and suggest that this aging cohort provides an important resource to discover genetic and environmental factors that promote prolonged health-span in addition to longer life-span.

  1. Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors’ Offspring

    Directory of Open Access Journals (Sweden)

    Kotaro Ozasa

    2018-04-01

    Full Text Available Cohorts of atomic bomb survivors—including those exposed in utero—and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors’ children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young.

  2. Implicit motor sequence learning and working memory performance changes across the adult life span

    Directory of Open Access Journals (Sweden)

    Sarah Nadine Meissner

    2016-04-01

    Full Text Available Although implicit motor sequence learning is rather well understood in young adults, effects of aging on this kind of learning are controversial. There is first evidence that working memory (WM might play a role in implicit motor sequence learning in young adults as well as in adults above the age of 65. However the knowledge about the development of these processes across the adult life span is rather limited. As the average age of our population continues to rise, a better understanding of age-related changes in motor sequence learning and potentially mediating cognitive processes takes on increasing significance. Therefore, we investigated aging effects on implicit motor sequence learning and WM. Sixty adults (18-71 years completed verbal and visuospatial n-back tasks and were trained on a serial reaction time task. Randomly varying trials served as control condition. To further assess consolidation indicated by off-line improvement and reduced susceptibility to interference, reaction times (RTs were determined 1 h after initial learning. Young and older but not middle-aged adults showed motor sequence learning. Nine out of 20 older adults (compared to one young/one middle-aged exhibited some evidence of sequence awareness. After 1 h, young and middle-aged adults showed off-line improvement. However, RT facilitation was not specific to sequence trials. Importantly, susceptibility to interference was reduced in young and older adults indicating the occurrence of consolidation. Although WM performance declined in older participants when load was high, it was not significantly related to sequence learning. The data reveal a decline in motor sequence learning in middle-aged but not in older adults. The use of explicit learning strategies in older adults might account for the latter result.

  3. Life span and tissue distribution of 111indium-labeled blood platelets in hypomagnesemic lambs

    International Nuclear Information System (INIS)

    Schneider, M.D.; Miller, J.K.; White, P.K.; Ramsey, N.

    1983-01-01

    Circulating platelets may be activated by exposed triple-helical collagen in atherosclerotic lesions in Mg-deficient ruminants. Autologous platelets, labeled in vitro with 111In and determined to be active, were injected into 5 hypomagnesemic and 3 control lambs fed semipurified diets with 100 or 2,000 mg of Mg/kg of feed for 3 months. During the first 68 hours, 111In concentrations were 11 times higher in packed cells than in plasma. Packed-cell 111In increased 60% during the first 2 hours, probably due to initial tissue sequestration and later release of labeled platelets. Thereafter, platelet half-life span averaged 60 and 63 hours for hypomagnesemic and control lambs. After 68 hours, lambs were injected with native vascular collagen fibrils at 500 micrograms/kg of body weight to initiate reversible platelet aggregation. Within 1 minute, 83% of packed-cell 111In disappeared from circulation. Thirty minutes later, the lambs were euthanatized and necropsied and in the lungs, liver, and spleen, 111In averaged 24%, 19%, and 9%, respectively, of 111In injected 68 hours earlier. Organ deposits were not affected by Mg intake, but 111In in the lungs was somewhat lower in 2 lambs injected with inactivated collagen. Pathologic changes induced by reversible platelet aggregation were compatible with right ventricular failure complicated by pulmonary edema, similar to changes in hypomagnesemic lambs that died spontaneously. Platelets in blood exposed to vascular lesions in hypomagnesemic ruminants could be a major mortality risk factor in grass tetany disease

  4. Attachment and the processing of social information across the life span: theory and evidence.

    Science.gov (United States)

    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 patterns of results that have emerged from these studies. The central proposition is that individuals who possess secure experience-based internal working models of attachment will process--in a relatively open manner--a broad range of positive and negative attachment-relevant social information. Moreover, secure individuals will draw on their positive attachment-related knowledge to process this information in a positively biased schematic way. In contrast, individuals who possess insecure internal working models of attachment will process attachment-relevant social information in one of two ways, depending on whether the information could cause the individual psychological pain. If processing the information is likely to lead to psychological pain, insecure individuals will defensively exclude this information from further processing. If, however, the information is unlikely to lead to psychological pain, then insecure individuals will process this information in a negatively biased schematic fashion that is congruent with their negative attachment-related experiences. In a comprehensive literature review, we describe studies that illustrate these patterns of attachment-related information processing from childhood to adulthood. This review focuses on studies that have examined specific components (e.g., attention and memory) and broader aspects (e.g., attributions) of social information processing. We also provide general conclusions and suggestions for future research.

  5. Age-Related Cognitive Effects of Videogame Playing Across the Adult Life span.

    Science.gov (United States)

    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.

  6. Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors' Offspring.

    Science.gov (United States)

    Ozasa, Kotaro; Grant, Eric J; Kodama, Kazunori

    2018-04-05

    Cohorts of atomic bomb survivors-including those exposed in utero-and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC) in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF) in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors' children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young.

  7. Japanese Legacy Cohorts: The Life Span Study Atomic Bomb Survivor Cohort and Survivors’ Offspring

    Science.gov (United States)

    Grant, Eric J; Kodama, Kazunori

    2018-01-01

    Cohorts of atomic bomb survivors—including those exposed in utero—and children conceived after parental exposure were established to investigate late health effects of atomic bomb radiation and its transgenerational effects by the Atomic Bomb Casualty Commission (ABCC) in the 1950s. ABCC was reorganized to the Radiation Effects Research Foundation (RERF) in 1975, and all work has been continued at RERF. The Life Span Study, the cohort of survivors, consists of about 120,000 subjects and has been followed since 1950. Cohorts of in utero survivors and the survivors’ children include about 3,600 and 77,000 subjects, respectively, and have been followed since 1945. Atomic bomb radiation dose was estimated for each subject based on location at the time of the bombing and shielding conditions from exposure, which were obtained through enormous efforts of investigators and cooperation of subjects. Outcomes include vital status, cause of death, and cancer incidence. In addition, sub-cohorts of these three cohorts were constructed to examine clinical features of late health effects, and the subjects have been invited to periodic health examinations at clinics of ABCC and RERF. They were also asked to donate biosamples for biomedical investigations. Epidemiological studies have observed increased radiation risks for malignant diseases among survivors, including those exposed in utero, and possible risks for some non-cancer diseases. In children of survivors, no increased risks due to parental exposure to radiation have been observed for malignancies or other diseases, but investigations are continuing, as these cohorts are still relatively young. PMID:29553058

  8. Verbal and Visual-Spatial Working Memory: What Develops over a Life Span?

    Science.gov (United States)

    Swanson, H. Lee

    2017-01-01

    This study investigates whether age-related changes in the structure of 5 complex working memory (WM) tasks (a) reflect a general or domain specific system, (b) follows a similar trajectory across different age spans, and (c) contribute domain general or domain specific resources to achievement measures. The study parsed the sample (N = 2,471)…

  9. Dependence of the average life span, mortality and osteosarcoma occurence in rats on the radiation dose absorbed (Sr 90)

    International Nuclear Information System (INIS)

    Shvedov, V.L.; Panteleev, L.I.

    1975-01-01

    The dose dependence of mortality and osteosarcoma development frequency is studied in white rats which have received 0.00005-5.0μCi/day of strontium-90 throughout their lives. It is shown that total mortality in the dose range 0-10 krad is a more sensitive test than osteosarcoma frequency, osteosarcomatosis hardly reducing the mean life span of the irradiated rats. (author)

  10. Resveratrol effects on life span and fertility of caenorhabditis elegans subject to 60Co gamma ray irradiation

    International Nuclear Information System (INIS)

    Ye Kai; Ji Chenbo; Guo Xirong; Gu Guixiong

    2011-01-01

    Caennorhabditis elegans was used as experimental model to investigate radiation effect of resveratrol on caenorhabditis elegans irradiated by 60 Co γ ray. Treatment with resveratrol can increase average life span and spawning rate, improve the survival rate of eggs, and protect their mitochondrion function of caenorhabditis elegans exposure to 60 Co γ ray. The results indicate that resveratrol has radiation protection effects, which might be related to its action on ROS decrease and mitochondrial defend. (authors)

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

    Science.gov (United States)

    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.

  12. Parthenogenetic reproduction of Diaphanosoma celebensis (Crustacea: Cladocera). Effect of algae and algal density on survival, growth, life span and neonate production

    Digital Repository Service at National Institute of Oceanography (India)

    Shrivastava, Y.; Mahambre, G.G.; Achuthankutty, C.T.; Fernandes, Brenda; Goswami, S.C.; Madhupratap, M.

    ) and Tetraselmis gracilis (Kylin), was determined. Growth was faster in the initial stage with all three diets but slowed down in later life. Increased food concentrations resulted in higher neonate production but reduced the life span of females. However, long...

  13. The Development of Memory Efficiency and Value-Directed Remembering across the Life Span: A Cross-Sectional Study of Memory and Selectivity

    Science.gov (United States)

    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…

  14. Reduction in life span on normal human fibroblasts exposed to low-dose radiation in heavy-ion radiation field

    International Nuclear Information System (INIS)

    Suzuki, Masao; Yamaguchi, Chizuru; Yasuda, Hiroshi; Uchihori, Yukio; Fujitaka, Kazunobu

    2003-01-01

    We studied the effect of in vitro life span in normal human fibroblasts exposed to chronically low-dose radiation in heavy-ion radiation field. Cells were cultured in a CO 2 incubator, which was set in the irradiation room for biological study of heavy ions in the Heavy Ion Medical Accelerator in Chiba (HIMAC) at National Institute of Radiological Sciences (NIRS), and exposed to scattered radiations produced with heavy-ion beams throughout the life span of the cell population. Absorbed dose, which was measured using a thermoluminescence dosimeter(TLD) and a Si-semiconductor detector, was to be 1.4 mGy per day when operating the HIMAC machine for biological experiments. The total population doubling number of the exposed cells reduced to 79-93% of non-exposed control cells in the three independent experiments. There is evidence that the exposure of chronically low-dose radiation in heavy-ion radiation field promotes the life-span reduction in cellular level. (author)

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

    Science.gov (United States)

    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.

  16. Dietary Resveratrol Does Not Affect Life Span, Body Composition, Stress Response, and Longevity-Related Gene Expression in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Stefanie Staats

    2018-01-01

    Full Text Available In this study, we tested the effect of the stilbene resveratrol on life span, body composition, locomotor activity, stress response, and the expression of genes encoding proteins centrally involved in ageing pathways in the model organism Drosophila melanogaster. Male and female w1118 D. melanogaster were fed diets based on sucrose, corn meal, and yeast. Flies either received a control diet or a diet supplemented with 500 µmol/L resveratrol. Dietary resveratrol did not affect mean, median, and maximal life span of male and female flies. Furthermore, body composition remained largely unchanged following the resveratrol supplementation. Locomotor activity, as determined by the climbing index, was not significantly different between control and resveratrol-supplemented flies. Resveratrol-fed flies did not exhibit an improved stress response towards hydrogen peroxide as compared to controls. Resveratrol did not change mRNA steady levels of antioxidant (catalase, glutathione-S-transferase, NADH dehydrogenase, glutathione peroxidase, superoxide dismutase 2 and longevity-related genes, including sirtuin 2, spargel, and I’m Not Dead Yet. Collectively, present data suggest that resveratrol does not affect life span, body composition, locomotor activity, stress response, and longevity-associated gene expression in w1118 D. melanogaster.

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

    Science.gov (United States)

    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 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.

  18. Dietary Resveratrol Does Not Affect Life Span, Body Composition, Stress Response, and Longevity-Related Gene Expression in Drosophila melanogaster.

    Science.gov (United States)

    Staats, Stefanie; Wagner, Anika E; Kowalewski, Bianca; Rieck, Florian T; Soukup, Sebastian T; Kulling, Sabine E; Rimbach, Gerald

    2018-01-11

    In this study, we tested the effect of the stilbene resveratrol on life span, body composition, locomotor activity, stress response, and the expression of genes encoding proteins centrally involved in ageing pathways in the model organism Drosophila melanogaster . Male and female w 1118 D. melanogaster were fed diets based on sucrose, corn meal, and yeast. Flies either received a control diet or a diet supplemented with 500 µmol/L resveratrol. Dietary resveratrol did not affect mean, median, and maximal life span of male and female flies. Furthermore, body composition remained largely unchanged following the resveratrol supplementation. Locomotor activity, as determined by the climbing index, was not significantly different between control and resveratrol-supplemented flies. Resveratrol-fed flies did not exhibit an improved stress response towards hydrogen peroxide as compared to controls. Resveratrol did not change mRNA steady levels of antioxidant ( catalase , glutathione-S-transferase , NADH dehydrogenase , glutathione peroxidase , superoxide dismutase 2 ) and longevity-related genes, including sirtuin 2 , spargel , and I'm Not Dead Yet . Collectively, present data suggest that resveratrol does not affect life span, body composition, locomotor activity, stress response, and longevity-associated gene expression in w 1118 D. melanogaster .

  19. The effects of constant and alternating temperatures on the reproductive potential, life span, and life expectancy of Anastrepha fraterculus (Wiedemann (Dipteria: Tephritidae

    Directory of Open Access Journals (Sweden)

    V. V. CARDOSO

    Full Text Available Ovarian development, oviposition, larval eclosion, ornithine decarboxylase (ODC activity, ovarian, testis and ejaculatory apodeme measurements (length, width, and area, and the number of spermatozoa of Anastrepha fraterculus (Wiedemann were analyzed at alternating (20º/6ºC and 20º/13°C and constant (6°C; 25°C temperatures. Life span and life expectancy were also analyzed for both genders. All the results suggest that temperature, especially alternating temperatures, increase not only male and female reproductive potential but also their life span and life expectancy. These changes can be a powerful strategy triggered by A. fraterculus as a means to survive the stressful temperature conditions found in winter in the apple production region in Brazil, enabling this species to increase its population density and cause apple damage when spring begins.

  20. The effects of constant and alternating temperatures on the reproductive potential, life span, and life expectancy of Anastrepha fraterculus (Wiedemann (Dipteria: Tephritidae

    Directory of Open Access Journals (Sweden)

    CARDOSO V. V.

    2002-01-01

    Full Text Available Ovarian development, oviposition, larval eclosion, ornithine decarboxylase (ODC activity, ovarian, testis and ejaculatory apodeme measurements (length, width, and area, and the number of spermatozoa of Anastrepha fraterculus (Wiedemann were analyzed at alternating (20masculine/6masculineC and 20masculine/13degreesC and constant (6degreesC; 25degreesC temperatures. Life span and life expectancy were also analyzed for both genders. All the results suggest that temperature, especially alternating temperatures, increase not only male and female reproductive potential but also their life span and life expectancy. These changes can be a powerful strategy triggered by A. fraterculus as a means to survive the stressful temperature conditions found in winter in the apple production region in Brazil, enabling this species to increase its population density and cause apple damage when spring begins.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    Gomez Fernando

    2012-12-01

    Full Text Available Abstract Background 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. Results 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. Conclusions 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

  3. Life-Cycle Monitoring of Long-Span PSC Box Girder Bridges through Distributed Sensor Network: Strategies, Methods, and Applications

    Directory of Open Access Journals (Sweden)

    Zheheng Chen

    2015-01-01

    Full Text Available Structural health monitoring (SHM has attracted much attention in recent years, which enables early warnings of structural failure, condition assessments, and rational maintenance/repair strategies. In the context of bridges, many long-span steel bridges in China have been installed with the SHM systems; however, the applications of the SHM in prestressed concrete (PSC bridges are still rather limited. On the other hand, the PSC box girder bridges are extensively used in highway and railway systems and premature damage of these bridges is often reported, resulting in considerable maintenance and/or replacement costs. First, this paper presents a state-of-art review on the SHM of long-span PSC bridges. Monitoring strategies, methods, and previous applications for these bridges are summarized and discussed. In order to well capture the behavior of the bridge during its whole life and to maximize the use of sensors, a life-cycle monitoring strategy is proposed, in which the sensor layout is determined according to requirements for construction monitoring, completion test, and in-service monitoring. A case study is made on a three-span PSC box girder bridge in China. The system configuration, sensor layout, and data communications, and so forth, are presented. The up-to-date monitored structural responses are analyzed and compared with the design values.

  4. How stable is the personal past? Stability of most important autobiographical memories and life narratives across eight years in a life span sample.

    Science.gov (United States)

    Köber, Christin; Habermas, Tilmann

    2017-10-01

    Considering life stories as the most individual layer of personality (McAdams, 2013) implies that life stories, similar to personality traits, exhibit some stability throughout life. Although stability of personality traits has been extensively investigated, only little is known about the stability of life stories. We therefore tested the influence of age, of the proportion of normative age-graded life events, and of global text coherence on the stability of the most important memories and of brief entire life narratives as 2 representations of the life story. We also explored whether normative age-graded life events form more stable parts of life narratives. In a longitudinal life span study covering up to 3 measurements across 8 years and 6 age groups (N = 164) the stability of important memories and of entire life narratives was measured as the percentage of events and narrative segments which were repeated in later tellings. Stability increased between ages 8 and 24, leveling off in middle adulthood. Beyond age, stability of life narratives was also predicted by proportion of normative age-graded life events and by causal-motivational text coherence in younger participants. Memories of normative developmental and social transitional life events were more stable than other memories. Stability of segments of life narratives exceeded the stability of single most important memories. Findings are discussed in terms of cognitive, personality, and narrative psychology and point to research questions in each of these fields. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

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

    Science.gov (United States)

    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).

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

    Science.gov (United States)

    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.

  7. Language decline across the life span: findings from the Nun Study.

    Science.gov (United States)

    Kemper, S; Greiner, L H; Marquis, J G; Prenovost, K; Mitzner, T L

    2001-06-01

    The present study examines language samples from the Nun Study. Measures of grammatical complexity and idea density were obtained from autobiographies written over a 60-year span. Participants who had met criteria for dementia were contrasted with those who did not. Grammatical complexity initially averaged 4.78 (on a 0-to-7-point scale) for participants who did not meet criteria for dementia and declined .04 units per year; grammatical complexity for participants who met criteria for dementia initially averaged 3.86 and declined .03 units per year. Idea density averaged 5.35 propositions per 10 words initially for participants who did not meet criteria for dementia and declined an average of .03 units per year, whereas idea density averaged 4.34 propositions per 10 words initially for participants who met criteria for dementia and declined .02 units per year. Adult experiences, in general, did not moderate these declines.

  8. Platelet associated IgG, platelet mean life span and treatment with intravenous immunoglobulin in idiopathic thrombocytopenic purpura

    International Nuclear Information System (INIS)

    Nieminen, U.; Syrjaelae, M.; Ikkala, E.; Myllylae, G.

    1988-01-01

    The clinical significance of platelet associated IgG in ITP detected by direct platelet suspension immunofluorescence test (PSIFT) was studied. The platelet mean life span (MLS) was measured with 111 In-labelled platelets in 17 adult patients. All the patients had shortened platelet MLS. The direct PSIFT was positive in 14 patients. Patients were initially treated with prednisone; 12 patients with poor response to the drug were splenectomised. 8 of these 12 patients were treated with intravenous immunoglobulin (IvIg) before splenectomy. The response to IvIg was as good or better in the 3 patients with negative PSIFT, than in the 5 patients with positive PSIFT. (author)

  9. Life-span studies in 226Ra-injected animals: Effect of low doses, effect of a decorporative treatment

    International Nuclear Information System (INIS)

    Schoeters, G.E.R.; Vanderborght, O.L.J.

    1986-01-01

    A life-span radiation effects study was performed in mice injected with several doses of 226 Ra. The study included 788 male C57Bl mice. For the removal of the 226 Ra, half the mice were treated daily with a diet 5% of which was sodium-alginate. The experiment revealed that mice that received the lowest dose of 226 Ra lived significantly longer than controls, and, despite appreciable skeletal removal of 226 Ra as a result of decorporative treatment, no biological benefit was observed in treated animals. 19 refs., 4 figs., 3 tabs

  10. Changes in genetic architecture during relaxation in Drosophila melanogaster selected on divergent virgin life span

    NARCIS (Netherlands)

    Vermeulen, CJ; Bijlsma, R

    Artificial selection experiments often confer important information on the genetic correlations constraining the evolution of life history. After artificial selection has ceased however, selection pressures in the culture environment can change the correlation matrix again. Here, we reinvestigate

  11. Social relationships and physiological determinants of longevity across the human life span.

    Science.gov (United States)

    Yang, Yang Claire; Boen, Courtney; Gerken, Karen; Li, Ting; Schorpp, Kristen; Harris, Kathleen Mullan

    2016-01-19

    Two decades of research indicate causal associations between social relationships and mortality, but important questions remain as to how social relationships affect health, when effects emerge, and how long they last. Drawing on data from four nationally representative longitudinal samples of the US population, we implemented an innovative life course design to assess the prospective association of both structural and functional dimensions of social relationships (social integration, social support, and social strain) with objectively measured biomarkers of physical health (C-reactive protein, systolic and diastolic blood pressure, waist circumference, and body mass index) within each life stage, including adolescence and young, middle, and late adulthood, and compare such associations across life stages. We found that a higher degree of social integration was associated with lower risk of physiological dysregulation in a dose-response manner in both early and later life. Conversely, lack of social connections was associated with vastly elevated risk in specific life stages. For example, social isolation increased the risk of inflammation by the same magnitude as physical inactivity in adolescence, and the effect of social isolation on hypertension exceeded that of clinical risk factors such as diabetes in old age. Analyses of multiple dimensions of social relationships within multiple samples across the life course produced consistent and robust associations with health. Physiological impacts of structural and functional dimensions of social relationships emerge uniquely in adolescence and midlife and persist into old age.

  12. Developmental Differentiation and Binding of Mental Processes with g through the Life-Span

    Directory of Open Access Journals (Sweden)

    Andreas Demetriou

    2017-05-01

    Full Text Available Integration/differentiation of mental processes is major mechanism of development. Developmental theories ascribe intellectual development to it. In psychometric theory, Spearman’s law of diminishing returns postulates that increasing g allows increasing differentiation of cognitive abilities, because increased mental power allows variable investment in domain-specific learning. Empirical evidence has been inconsistent so far, with some studies supporting and others contradicting this mechanism. This state of affairs is due to a developmental phenomenon: Both differentiation and strengthening of relations between specific processes and g may happen but these changes are phase-specific and ability-specific, depending upon the developmental priorities in the formation of g in each phase. We present eight studies covering the age span from 4 to 85 years in support of this phenomenon. Using new powerful modeling methods we showed that differentiation and binding of mental processes in g occurs in cycles. Specific processes intertwine with g at the beginning of cycles when they are integrated into it; when well established, these processes may vary with increasing g, reflecting its higher flexibility. Representational knowledge, inductive inference and awareness of it, and grasp of logical constraints framing inference are the major markers of g, first intertwining with in their respective cycles and differentiating later during the periods of 2–6, 7–11, and 11–20 years, respectively. The implications of these findings for an overarching cognitive developmental/differential theory of human mind are discussed.

  13. Corruption analysis and life span forecast research on sylphon bellows of nuclear-powered steam system of ship

    International Nuclear Information System (INIS)

    Song Chao; Chen Lisheng; Song Meicun; Wang Wei

    2012-01-01

    The fracture of the corrugated pipe has a dad effect to the operation of reactor which can cause the small-break LOCA. The corrosion is the key reason of the fracture. On the base of the analysis on corruption reason of the sylphon bellows and combine the characteristic of the limited sample point of it, the Grey theory was used in the assessment of corrosion life span of corrugated pipe in nuclear steam system. Through applying the GM (1, 1) model in inferring the discipline of corrosion quantity and combining traditional statistical method, the corrosion life of steam pipe was evaluated. It indicates that the model is precise, simple and the result is reliable. (authors)

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

    International Nuclear Information System (INIS)

    Shitara, Shingo; Kakeda, Minoru; Nagata, Keiko; Hiratsuka, Masaharu; Sano, Akiko; Osawa, Kanako; Okazaki, Akiyo; Katoh, Motonobu; Kazuki, Yasuhiro; Oshimura, Mitsuo; Tomizuka, Kazuma

    2008-01-01

    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-β-galactosidase activity. Furthermore, the hTERT-HAC/hPF clones continued growing beyond 120 days 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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  17. Neoplastic and life-span effects of chronic exposure to tritium. I. Effects on adult rats exposed during pregnancy

    International Nuclear Information System (INIS)

    Cahill, D.F.; Wright, J.F.; Godbold, J.H.; Ward, J.M.; Laskey, J.W.; Tompkins, E.A.

    1975-01-01

    Female Sprague-Dawley rats were continuously exposed to equilibrium levels of tritiated water (HTO) during pregnancy. The tritium activities were 1, 10, 50, and 100 μCi HTO/ml body water which provided cumulative, whole-body radiation doses of approximately 6.6, 66, 330, and 660 rads. Administration of the radioisotope was terminated at parturition. Throughout their life-spans and at autopsy, the dams showed an increased incidence of mammary fibroadenomas at exposure to 330 and 660 rads. Although the data for the incidence of malignant mammary neoplasms were consistent with a linear dose response, the small numbers of tumors preclude specific definition of the dose-response curve. Postexposure life-spans for dams chronically exposed to 66, 330, and 660 rads during pregnancy were reduced by 14, 24, and 22 percent, respectively. Accelerated aging was also demonstrated in these rats: The mean age for mammary fibroadenoma onset decreased with an increasing dose of radiation. (U.S.)

  18. Lifelong susceptibility to acoustic trauma: Changing patterns of chochlear damage over the life span of the mouse

    Energy Technology Data Exchange (ETDEWEB)

    Henry, K.R.

    1983-01-01

    Age-related differences in susceptibility to noise-induced threshold shift (NITS) were examined over the entire life span of the CBA/J mouse. Mice of varying ages were given a single 5-min exposure to a 124-dB octave-band (12-24 kHz) noise. Susceptibility began at 15-16 days postpartum and increased rapidly until approximately 20 days of age. During this phase, NITS (as measured by increased action potential threshold) was greatest at 16 kHz. Overall susceptibility was consistently high from 20 to 90 days. During this phase, NITS became most severe at 32 kHz. From 120 days until beyond the end of its acturarial life span (527 days), NITS no longer occured at 2-16 kHz, but the 64-kHz response retained its susceptibility to acoustic trauma. Mice at 20 and 60 days of age showed the same pattern of decreasing susceptibility as the intensity of the noise exposure was reduced to 114 and 104 dB, indicating that the absence of a tightly restricted critical period is not peculiar to a particular sound pressure level.

  19. Baicalein modulates stress-resistance and life span in C. elegans via SKN-1 but not DAF-16.

    Science.gov (United States)

    Havermann, Susannah; Humpf, Hans-Ulrich; Wätjen, Wim

    2016-09-01

    The flavonoid baicalein has been demonstrated to be an activator of the transcription factor Nrf2 in mammalian cell lines. We show that it further modulates the Nrf2 homolog SKN-1 in Caenorhabditis elegans and by this pathway mediates beneficial effects in the nematode: baicalein enhances the resistance of C. elegans against lethal thermal and sodium arsenite stress and dose-dependently prolongs the life span of the nematode. Using RNA interference against SKN-1 we were able to show that the induction of longevity and the enhanced stress-resistance were dependent on this transcription factor. DAF-16 (homolog to mammalian FOXO) is another pivotal aging-related transcription factor in the nematode. We demonstrate that DAF-16 does not participate in the beneficial effects of baicalein: since baicalein causes no increase in the nuclear translocation of DAF-16 (DAF-16::GFP expressing strain, incubation time: 1h) and it still induces longevity even in a DAF-16 loss-of-function strain, we conclude, that baicalein increases stress-resistance and life span in C. elegans via SKN-1 but not DAF-16. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Effects of storage media on the green life span and culinary qualities ...

    African Journals Online (AJOL)

    Sawdust (SD) and ricehusk (RH)) used singly or mixed in varying proportions and enclosed in polyethylene were used to study the storage life of mature green plantain fruits. There were two control treatments comprising fruits sealed in polyethylene without plant residue and fruits kept on laboratory shelf. Fruits were sealed ...

  1. Bile Acid Look-Alike Controls Life Span in C. elegans

    NARCIS (Netherlands)

    Groen, Albert K.; Kuipers, Folkert

    2013-01-01

    Extensive transcriptional networks maintain sterol homeostasis across species, underscoring the importance of sterol balance for healthy life. Magner et al. (2013) now show that, in C. elegans, the nuclear receptor NHR-8 is key in regulation of cholesterol balance and production of dafachronic acid,

  2. Healthy Aging After Age 65: A Life-Span Health Production Function Approach.

    Science.gov (United States)

    Ferdows, Nasim B; Jensen, Gail A; Tarraf, Wassim

    2018-06-01

    This article examines the determinants of healthy aging using Grossman's framework of a health production function. Healthy aging, sometimes described as successful aging, is produced using a variety of inputs, determined in early life, young adulthood, midlife, and later life. A healthy aging production function is estimated using nationally representative data from the 2010 and 2012 Health and Retirement Study on 7,355 noninstitutionalized seniors. Using a simultaneous equation mediation model, we quantify how childhood factors contribute to healthy aging, both directly and indirectly through their effects on mediating adult outcomes. We find that favorable childhood conditions significantly improve healthy aging scores, both directly and indirectly, mediated through education, income, and wealth. We also find that good health habits have positive effects on healthy aging that are larger in magnitude than the effects of childhood factors. Our findings suggest that exercising, maintaining proper weight, and not smoking are likely to translate into healthier aging.

  3. Fullness of life as minimal unit: Science, technology, engineering, and mathematics (STEM) learning across the life span.

    NARCIS (Netherlands)

    Roth, W.-M.; Eijck, van M.W.

    2011-01-01

    Challenged by a National Science Foundation–funded conference, 2020 Vision: The Next Generation of STEM Learning Research, in which participants were asked to recognize science, technology, engineering, and mathematics (STEM) learning as lifelong, life-wide, and life-deep, we draw upon 20 years of

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

    NARCIS (Netherlands)

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

    2010-01-01

    Background: 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

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

    Science.gov (United States)

    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.

  6. Effect of continuous exposure to very low dose rates of gamma rays on life span and neoplasia in mice

    International Nuclear Information System (INIS)

    Tanaka, I.B. III; Tanaka, Satoshi; Ichinohe, Kazuaki; Matsumoto, Tsuneya; Otsu, Hiroshi; Oghiso, Yoichi; Sato, Fumiaki; Matsushita, Satoru

    2008-01-01

    Late effects of continuous exposure to ionizing radiation are potential hazards to workers in radiation facilities as well as to the general public. In the recent years, low-dose-rate and low-dose effects have become a serious concern. Using a total of 4,000 mice, we studied the late biological effects of chronic exposure to low-dose-rate radiation on life span and neoplasia. Two thousand male and 2000 female 8-week-old specific pathogen free (SPF) B6C3F1 mice were randomly divided into 4 groups, one non-irradiated (control) and three irradiated. The irradiated groups were exposed to 137 Cs gamma rays at dose-rates of 21, 1.1 and 0.05 mGy day -1 for approximately 400 days with total doses equivalent to 8000, 400 and 20 mGy, respectively. All mice were kept under SPF conditions until natural death and pathological examination was performed to determine the cause of death. Statistical analyses showed that the life spans of mice of both sexes irradiated with 21 mGy day -1 (P -1 (P 86.7% of all deaths. Compared to the non-irradiated controls, incidences of lethal neoplasms were significantly increased for myeloid leukaemia and hemangiosarcoma in males, soft tissue neoplasms and malignant granulosa cell tumors in females exposed to 21 mGy day -1 . The number of multiple primary neoplasms per mouse was significantly increased in mice irradiated at 21 mGy day -1 . Our results suggest that life shortening in mice continuously exposed to low dose-rate gamma rays is due to early death from a variety of neoplasms and not from increased incidence of specific lethal neoplasms. (author)

  7. Delayed radiation injury of gut-exposed and gut-shielded mice. II. The decrement in life span

    International Nuclear Information System (INIS)

    Spalding, J.F.; Archuleta, R.F.; Prine, J.R.

    1978-01-01

    Two mouse strains (RF/J and C57B1/6J) were exposed to x-ray doses totaling 400, 800, and 1200 rad. Total doses were given in 200-rad fractions at 7-day intervals to the whole body, gut only, or bone tissue with the gut shielded. Animals were anesthetized during exposure. Two control groups were used. A sham control group was anesthetized but not exposed to x rays, and another control group received neither anesthesia nor x-radiation. All mice were retained in a standard laboratory environment for observations on life span and histopathology at death. Life shortening was observed in all irradiated groups of strain RF/J mice and was attributed primarily to an increase in incidence and/or earlier onset of neoplasia. Life shortening was observed in the C57B1/6J whole-body exposed mice, but the effect appeared to be noncarcinogenic. Shielding of the bone or gut tissue proved to have a 100% sparing effect in strain C57 mice and none in strain RF mice. In both mouse strains, the sham control groups (anesthetized but not irradiated) showed approximately 8% life shortening below the non-anesthetized control groups and increased incidences of neoplasia of approximately 40%, suggesting that sodium pentabarbital may be as carcinogenic as x-radiation

  8. A drastic reduction in the life span of cystatin C L68Q carriers due to life-style changes during the last two centuries.

    Directory of Open Access Journals (Sweden)

    Astridur Palsdottir

    2008-06-01

    Full Text Available Hereditary cystatin C amyloid angiopathy (HCCAA is an autosomal dominant disease with high penetrance, manifest by brain hemorrhages in young normotensive adults. In Iceland, this condition is caused by the L68Q mutation in the cystatin C gene, with contemporary carriers reaching an average age of only 30 years. Here, we report, based both on linkage disequilibrium and genealogical evidence, that all known copies of this mutation derive from a common ancestor born roughly 18 generations ago. Intriguingly, the genealogies reveal that obligate L68Q carriers born 1825 to 1900 experienced a drastic reduction in life span, from 65 years to the present-day average. At the same time, a parent-of-origin effect emerged, whereby maternal inheritance of the mutation was associated with a 9 year reduction in life span relative to paternal inheritance. As these trends can be observed in several different extended families, many generations after the mutational event, it seems likely that some environmental factor is responsible, perhaps linked to radical changes in the life-style of Icelanders during this period. A mutation with such radically different phenotypic effects in reaction to normal variation in human life-style not only opens the possibility of preventive strategies for HCCAA, but it may also provide novel insights into the complex relationship between genotype and environment in human disease.

  9. Research of the low dose gamma-irradiation influence on life span and aging speed of Drosophila melanogaster

    International Nuclear Information System (INIS)

    Moskalev, A.

    2003-01-01

    Full text: Researches of radioinduced life span alteration of Drosophila which is carried out in our laboratory in 1996-2003 years, have revealed interrelation between mutations of several genes of DNA repair and apoptosis pathways with low doses ionizing irradiation and speed of aging. It was used Drosophila individuals, developing in conditions of a chronic low dose irradiation or on nutrition medium with apoptosis inducer etoposide addition. The exposition doze was 0.17 sGy/h. The absorbed doze for one generation (from an embryo stage up to an imago start, 10-12 days) corresponded 60 sGy. Etoposide treatment carried out on preimago stages (5 mkM in a nutrient medium n concentration). We investigated the life span after irradiation and etoposide treatment of Drosophila melanogaster laboratory populations with defects of some genes of DNA repair machinery and apoptosis pathways in homozygous and heterozygous state, such as mei-41 (ATM homolog), two alleles of Dcp-1 (Drosophila caspase), dArk (Apaf-1 homolog), rpr, grim, hid, three alleles of th (IAP homolog), wg (Wnt family member). It is shown, that the irradiation and etoposide treatment of these strains results in life span change depending on a genotype of the investigated line. The results will be considering in the report. As well, the analysis of age-dependent change of nervous system activity (as the test of aging speed) of Drosophila melanogaster imago was carried out. It was shown, that the irradiation of strains with the increased apoptosis sensitivity results in elevated nervous - muscular activity of imago during all experiment periods. At th1 strain increase of activity in comparison with the control in the first week has made 41 %, and in two subsequent - about 80 %. Last week authentic increase did not observe. At th4 strain statistically significant increase of activity in comparison with the control observed in the first week of experiment (18 %), in the second (67 %) and the fourth (88 %). The

  10. Differential effects of the extracellular microenvironment on human embryonic stem cell differentiation into keratinocytes and their subsequent replicative life span.

    Science.gov (United States)

    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

  11. Motivation for social contact across the life span: a theory of socioemotional selectivity.

    Science.gov (United States)

    Carstensen, L L

    1992-01-01

    Older people engage in social interaction less frequently than their younger counterparts. As I mentioned at the start, the change has been interpreted in largely negative terms. Yet when asked about their social relationships, older people describe them as satisfying, supportive, and fulfilling. Marriages are less negative and more positive. Close relationships with siblings are renewed, and relationships with children are better than ever before. Even though older people interact with others less frequently than younger people do, old age is not a time of misery, rigidity, or melancholy. Rather than present a paradox, I argue here that decreasing rates of contact reflect a reorganization of the goal hierarchies that underlie motivation for social contact and lead to greater selectivity in social partners. This reorganization does not occur haphazardly. Self-definition, information seeking, and emotion regulation are ranked differently depending not only on past experiences, but on place in the life cycle and concomitant expectations about the future. I contend that the emphasis on emotion in old age results from a recognition of the finality of life. In most people's lives this does not appear suddenly in old age but occurs gradually across adulthood. At times, however, life events conspire to bring about endings more quickly. Whether as benign as a geographical relocation or as sinister as a fatal disease, endings heighten the salience of surrounding emotions. When each interaction with a grandchild or good-bye kiss to a spouse may be the last, a sense of poignancy may permeate even the most casual everyday experiences. When the regulation of emotion assumes greatest priority among social motives, social partners are carefully chosen. The most likely choices will be long-term friends and loved ones, because they are most likely to provide positive emotional experiences and affirm the self. Information seeking will motivate some social behavior, but for reasons

  12. Life span studies on mice exposed to heavy charged particles or photons: preliminary results

    International Nuclear Information System (INIS)

    Ainsworth, E.J.

    1980-01-01

    This chapter summarizes the results currently available where dose-dependent mortality is compared among the single cohort that received fractionated doses of carbon ions and the first replicate that received single doses. At this time, 17% mortality has occurred in both groups and had enhanced life shortening been produced by fractionation of the carbon ion dose, somewhat higher mortality might be expected. Cautious interpretation of these preliminary results is necessary, but the mortality data available at this time provides no evidence for enhancement by dose fractionation with carbon ions. In sum, at this time, it appears the Q factor used for fission spectrum neutrons could be conservative if it were used for assessment of risk following exposure to 400 MeV carbon ions

  13. Language Development across the Life Span: A Neuropsychological/Neuroimaging Perspective

    Directory of Open Access Journals (Sweden)

    Mónica Rosselli

    2014-01-01

    Full Text Available Language development has been correlated with specific changes in brain development. The aim of this paper is to analyze the linguistic-brain associations that occur from birth through senescence. Findings from the neuropsychological and neuroimaging literature are reviewed, and the relationship of language changes observable in human development and the corresponding brain maturation processes across age groups are examined. Two major dimensions of language development are highlighted: naming (considered a major measure of lexical knowledge and verbal fluency (regarded as a major measure of language production ability. Developmental changes in the brain lateralization of language are discussed, emphasizing that in early life there is an increase in functional brain asymmetry for language, but that this asymmetry changes over time, and that changes in the volume of gray and white matter are age-sensitive. The effects of certain specific variables, such as gender, level of education, and bilingualism are also analyzed. General conclusions are presented and directions for future research are suggested.

  14. A Transcriptome Survey Spanning Life Stages and Sexes of the Harlequin Bug, Murgantia histrionica

    Directory of Open Access Journals (Sweden)

    Michael E. Sparks

    2017-05-01

    Full Text Available The harlequin bug, Murgantia histrionica (Hahn, is an agricultural pest in the continental United States, particularly in southern states. Reliable gene sequence data are especially useful to the development of species-specific, environmentally friendly molecular biopesticides and effective biolures for this insect. Here, mRNAs were sampled from whole insects at the 2nd and 4th nymphal instars, as well as sexed adults, and sequenced using Illumina RNA-Seq technology. A global assembly of these data identified 72,540 putative unique transcripts bearing high levels of similarity to transcripts identified in other taxa, with over 99% of conserved single-copy orthologs among insects being detected. Gene ontology and protein family analyses were conducted to explore the functional potential of the harlequin bug’s gene repertoire, and phylogenetic analyses were conducted on gene families germane to xenobiotic detoxification, including glutathione S-transferases, carboxylesterases and cytochrome P450s. Genic content in harlequin bug was compared with that of the closely related invasive pest, the brown marmorated stink bug, Halyomorpha halys (Stål. Quantitative analyses of harlequin bug gene expression levels, experimentally validated using quantitative real-time PCR, identified genes differentially expressed between life stages and/or sexes.

  15. The relationship of cancer mortality to life span and food supply rate

    International Nuclear Information System (INIS)

    Totter, J.R.; Adler, H.I.; Storer, J.B.

    1985-01-01

    Survival curves for men and women dying from cardiovascular disease and similar curves for those dying from cancer in 47 countries were compared with the 1970-1974 per capita incomes of the inhabitants. The data were taken chiefly from 1964 life tables. The steepest survival curves were found in countries with the highest incomes. Comparison of the survival curves in different countries and comparison of cardiovascular survival with cancer survival curves indicate that both groups of diseases are probably diseases of senescence. The differences in survival slopes are interpreted as homeostatic responses in the population to rate of food intake. The response protects the population against long-term effects of changes in food supply by promoting differential reproduction of offspring best suited to the food supply rate fro the environment. The response to food supply rate complicates calculation of the effects of protracted exposure to low-level ionizing radiation because the radiation exposure appears to mimic the effec of extra food

  16. The size effect in corrosion greatly influences the predicted life span of concrete infrastructures.

    Science.gov (United States)

    Angst, Ueli M; Elsener, Bernhard

    2017-08-01

    Forecasting the life of concrete infrastructures in corrosive environments presents a long-standing and socially relevant challenge in science and engineering. Chloride-induced corrosion of reinforcing steel in concrete is the main cause for premature degradation of concrete infrastructures worldwide. Since the middle of the past century, this challenge has been tackled by using a conceptual approach relying on a threshold chloride concentration for corrosion initiation ( C crit ). All state-of-the-art models for forecasting chloride-induced steel corrosion in concrete are based on this concept. We present an experiment that shows that C crit depends strongly on the exposed steel surface area. The smaller the tested specimen is, the higher and the more variable C crit becomes. This size effect in the ability of reinforced concrete to withstand corrosion can be explained by the local conditions at the steel-concrete interface, which exhibit pronounced spatial variability. The size effect has major implications for the future use of the common concept of C crit . It questions the applicability of laboratory results to engineering structures and the reproducibility of typically small-scale laboratory testing. Finally, we show that the weakest link theory is suitable to transform C crit from small to large dimensions, which lays the basis for taking the size effect into account in the science and engineering of forecasting the durability of infrastructures.

  17. The relationship between women's body satisfaction and self-image across the life span: the role of cognitive control.

    Science.gov (United States)

    Webster, Jessica; Tiggemann, Marika

    2003-06-01

    The authors examined the relationship between body dissatisfaction and self-image across the life span. A sample of 106 women between the ages of 20 and 65 years completed questionnaire measures of body dissatisfaction, body importance, cognitive control over the body, self-concept, and self-esteem. The authors found that body dissatisfaction and body importance did not differ among the groups of women who were younger, middle aged, and older. Although body dissatisfaction was related to self-concept and self-esteem for the entire sample, the strength of that relationship reduced with increasing age and increasing perceptions of cognitive control. The authors concluded that the cognitive strategies of women who were older protect their self-concept and self-esteem from the influence of body dissatisfaction.

  18. Tissue characteristics of high- and low-incidence plutonium-induced osteogenic sarcoma sites in life-span beagles

    International Nuclear Information System (INIS)

    Miller, S.C.; Jee, W.S.S.; Smith, J.M.; Wronski, T.J.

    1986-01-01

    On the basis of information gathered from the 239 Pu life-span study in beagles at the University of Utah, the tissue features were found to be characteristic of high-incidence bone-tumor sites compared to low-incidence sites included more hematopoietic tissues in the bone marrow; greater trabecular bone mass; greater bone remodeling rates; greater mineral apposition rates; greater density and activity of bone surface cells; greater density of putative bone-cell precursors; greater initial uptake of plutonium on bone surfaces; and greater marrow vascular volumes and a venous sinusoidal bed. Although most of these studies are not yet complete, the information being collected should contribute to our understanding of the mechanisms of radiation-induced osteogenic sarcomas. This should aid in predicting the types and characteristics of osseous tissues where radiation-induced osteogenic sarcomas may arise in humans. 25 refs., 4 figs., 3 tabs

  19. Life span study. Report Number 1. Description of study mortality in the medical subsample, October 1950-June 1958

    Energy Technology Data Exchange (ETDEWEB)

    Beebe, G W; Ishida, Morihiro; Jablon, Seymour

    1961-02-15

    The Life Span Study is designed to evaluate the late mortality effects of the radiation and other trauma received by the survivors of the Hiroshima and Nagasaki A-bombs. No evidence of higher general mortality was seen in the more heavily irradiated groups. When mortality from specific causes were studied the well known leukemogenic properties of radiation were clearly reflected, but for no other causes of death were radiation effects seen. An apparent effect in the area of anemia seems, at least in part, to result from diagnostic difficulties in the blood dyscrasias, inasmuch as some leukemias were so classified. It is also possible that for the blood forming organs the effects of radiation go somewhat beyond the production of classical leukemia. More intensive study of a very much larger body of data is now under way. 41 references, 1 figure, 22 tables.

  20. Statistical modeling of biomedical corpora: mining the Caenorhabditis Genetic Center Bibliography for genes related to life span

    Directory of Open Access Journals (Sweden)

    Jordan MI

    2006-05-01

    Full Text Available Abstract Background The statistical modeling of biomedical corpora could yield integrated, coarse-to-fine views of biological phenomena that complement discoveries made from analysis of molecular sequence and profiling data. Here, the potential of such modeling is demonstrated by examining the 5,225 free-text items in the Caenorhabditis Genetic Center (CGC Bibliography using techniques from statistical information retrieval. Items in the CGC biomedical text corpus were modeled using the Latent Dirichlet Allocation (LDA model. LDA is a hierarchical Bayesian model which represents a document as a random mixture over latent topics; each topic is characterized by a distribution over words. Results An LDA model estimated from CGC items had better predictive performance than two standard models (unigram and mixture of unigrams trained using the same data. To illustrate the practical utility of LDA models of biomedical corpora, a trained CGC LDA model was used for a retrospective study of nematode genes known to be associated with life span modification. Corpus-, document-, and word-level LDA parameters were combined with terms from the Gene Ontology to enhance the explanatory value of the CGC LDA model, and to suggest additional candidates for age-related genes. A novel, pairwise document similarity measure based on the posterior distribution on the topic simplex was formulated and used to search the CGC database for "homologs" of a "query" document discussing the life span-modifying clk-2 gene. Inspection of these document homologs enabled and facilitated the production of hypotheses about the function and role of clk-2. Conclusion Like other graphical models for genetic, genomic and other types of biological data, LDA provides a method for extracting unanticipated insights and generating predictions amenable to subsequent experimental validation.

  1. The Effect of ACP₁-ADA₁ Genetic Interaction on Human Life Span.

    Science.gov (United States)

    Lucarini, Nazzareno; Napolioni, Valerio; Magrini, Andrea; Gloria, Fulvia

    2012-12-01

    Acid phosphatase (ACP₁) is a polymorphic enzyme that catalyzes the conversion of flavin-mononucleotide (FMN) to riboflavin and regulates the cellular concentration of flavin-adenine-dinucleotide (FAD) and, consequently, energy metabolism. Its activity is modulated by adenosine deaminase locus 1 (ADA₁) genotype. The aim of our work is to verify whether individuals with a high proportion of ACP₁ f-isozyme and carrying the ADA₁*2 allele, displaying the highest phosphatase activity, may have a higher life expectancy. Genomic DNA was extracted from the peripheral blood of 569 females and 509 males (18 to 106 years of age) randomly recruited from Central Italy. These samples were subdivided into three sex-specific age groups (the ages of women are in square bracket): Class 1: age 88 [>91]. ACP₁and ADA₁ singlenucleotide polymorphisms (SNPs) were genotyped by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) methods and statistical analyses were performed with SPSS 14.0. The results showed a larger proportion of Class 3 individuals displaying high ACP₁ f-isozyme concentration and carrying the ADA₁*2 allele than those individuals of Class 2 and Class 2 plus Class 1. Thus, we postulate that in Class 3 individuals the high phosphatase activity, resulting from the combined presence of high ACP₁ f-isozyme concentration and the ADA₁*2 allele, lowers the rate of glycolysis that may reduce the amount of metabolic calories and, in turn, activate Sirtuin genes that protect cells against age-related diseases. Copyright © 2013 Wayne State University Press, Detroit, Michigan 48201-1309.

  2. Late effects of selected immunosuppressants on immunocompetence, disease incidence, and mean life-span. III. Disease incidence and life expectancy. [Mice, x radiation

    Energy Technology Data Exchange (ETDEWEB)

    Peter, C P; Perkins, E H; Peterson, W J; Walburg, H E; Makinodan, T

    1975-01-01

    The effect of various immunosuppressive treatments on mean life-span and disease incidence have been studied. Significant life shortening was seen only in mice which received X-irradiation early in life and can be ascribed primarily to an increased incidence of certain malignancies. Marginal life shortening was seen in cyclophosphamide-treated animals, however, survival patterns between those and control animals did not differ until 30 months of age and the magnitude of life-shortening never approached that seen in X-irradiated animals. Thymectomy, splenectomy or cortisone treatment did not alter survival. All immunosuppressive treatments enhanced mortality due to non-neoplastic diseases, however, only a small percentage of animals die with these disease entities. With the exception of cortisone all immunosuppressive treatments increased the incidence of neoplastic disease. However, their effects on various neoplastic processes were variable and unpredictable. Four primary patterns in terms of relative immune competence, disease incidence and life expectancy were seen. Thus, immunodepression may or may not correlate with increased disease incidence, which in turn may or may not have a life-shortening effect. These findings are discussed in terms of the marked reduction of both humoral and cell-mediated immunity normally seen in aged mice and the significance of postulated immune surveillance mechanisms to survival.

  3. [The course of attention deficit hyperactivity disorder (ADHD) over the life span].

    Science.gov (United States)

    Koumoula, A

    2012-06-01

    Attention Deficit Hyperactivity Disorder is a neurodevelopmental disorder, associated with the maturation of the nervous system and appearing on a standard proceeding with special cognitive impairments. For many years ADHD was concerned as a typical childhood disorder. Long-term studies though, showed that an important percentage of children with ADHD grew as adults with ADHD. The clinical picture varies with the developmental stage. In pre-school years (3-5 years) the clinical picture is characterized by excessive physical activity, difficulty in cooperation with peers and non-compliance to the recommendations of adults. In school age (6-12 years), apart from the nuclear symptoms of the disorder, as described in the classification systems, i.e. inattention, hyperactivity and impulsivity, oppositional behavior often occurs, conflicts with peers and academic problems. In adolescence hyperactivity lessens, conflicts with parents continue and high risk behaviors often appear. In adults physical activity usually decreases significantly, while inattention and impulsivity still remain. With the passing of time the number of symptoms are usually reduced, however the impact and impairment caused by the disorder remain. The diagnosis of ADHD in adults requires a retrospective diagnosis of ADHD in childhood. Since childhood, comorbid disorders are common, most times continuing until adult life. The Oppositional Defiant Disorder during childhood is related to the presenting of Antisocial Personality Disorder in adults. On the other hand, emotional disorders, which are also rather common in children, adolescents and adults with ADHD, can be due to either common biological mechanisms or the long-standing effect of psychosocial and environmental factors which follow people with ADHD. The relationship between ADHD and substance abuse has been a subject of research, with the view of the existence of Conduct Disorder being necessary for a person to present a Substance Use Disorder

  4. New strategies to prolong the in vivo life span of iron-based contrast agents for MRI.

    Directory of Open Access Journals (Sweden)

    Antonella Antonelli

    Full Text Available Superparamagnetic iron oxide (SPIO and ultra small superparamagnetic iron oxide (USPIO nanoparticles have been developed as magnetic resonance imaging (MRI contrast agents. Iron oxide nanoparticles, that become superparamagnetic if the core particle diameter is ~ 30 nm or less, present R1 and R2 relaxivities which are much higher than those of conventional paramagnetic gadolinium chelates. Generally, these magnetic particles are coated with biocompatible polymers that prevent the agglomeration of the colloidal suspension and improve their blood distribution profile. In spite of their potential as MRI blood contrast agents, the biomedical application of iron oxide nanoparticles is still limited because of their intravascular half-life of only few hours; such nanoparticles are rapidly cleared from the bloodstream by macrophages of the reticulo-endothelial system (RES. To increase the life span of these MRI contrast agents in the bloodstream we proposed the encapsulation of SPIO nanoparticles in red blood cells (RBCs through the transient opening of cell membrane pores. We have recently reported results obtained by applying our loading procedure to several SPIO nanoparticles with different chemical physical characteristics such as size and coating agent. In the current investigation we showed that the life span of iron-based contrast agents in the mice bloodstream was prolonged to 12 days after the intravenous injection of murine SPIO-loaded RBCs. Furthermore, we developed an animal model that implicates the pretreatment of animals with clodronate to induce a transient suppression of tissue macrophages, followed by the injection of human SPIO-loaded RBCs which make it possible to encapsulate nanoparticle concentrations (5.3-16.7 mM Fe higher than murine SPIO-loaded RBCs (1.4-3.55 mM Fe. The data showed that, when human RBCs are used as more capable SPIO nanoparticle containers combined with a depletion of tissue macrophages, Fe concentration in

  5. Implications of extreme life span in clonal organisms: millenary clones in meadows of the threatened seagrass Posidonia oceanica.

    Directory of Open Access Journals (Sweden)

    Sophie Arnaud-Haond

    Full Text Available The maximum size and age that clonal organisms can reach remains poorly known, although we do know that the largest natural clones can extend over hundreds or thousands of metres and potentially live for centuries. We made a review of findings to date, which reveal that the maximum clone age and size estimates reported in the literature are typically limited by the scale of sampling, and may grossly underestimate the maximum age and size of clonal organisms. A case study presented here shows the occurrence of clones of slow-growing marine angiosperm Posidonia oceanica at spatial scales ranging from metres to hundreds of kilometres, using microsatellites on 1544 sampling units from a total of 40 locations across the Mediterranean Sea. This analysis revealed the presence, with a prevalence of 3.5 to 8.9%, of very large clones spreading over one to several (up to 15 kilometres at the different locations. Using estimates from field studies and models of the clonal growth of P. oceanica, we estimated these large clones to be hundreds to thousands of years old, suggesting the evolution of general purpose genotypes with large phenotypic plasticity in this species. These results, obtained combining genetics, demography and model-based calculations, question present knowledge and understanding of the spreading capacity and life span of plant clones. These findings call for further research on these life history traits associated with clonality, considering their possible ecological and evolutionary implications.

  6. Life span study, 8

    International Nuclear Information System (INIS)

    Beebe, G.W.; Kato, Hiroo; Land, C.E.

    1978-02-01

    Since the last report, covering the experience of the 82,000 A-bomb survivors for the period 1950-72, there have been 1,704 deaths (by 30 September 1974) and total deaths now stand at 20,230 since 1 October 1950. For cancer the increase was 390 and the new total 3,957. The entire 1950-74 mortality experience, supplemented by tumor registry information for Hiroshima (1957-70) and Nagasaki (1958-70), has been re-analyzed. The leukemogenic effect that dominated any consideration of late mortality effects until recently had now been exceeded by the effect of radiation on forms of cancer other than leukemia. At the end of 1974 excess deaths numbered about 85 for leukemia and 100 for other forms of cancer among the 82,000 A-bomb survivors under study. Sites of cancer that seemed especially involved in the continued increase in absolute risk estimates for all forms of cancer except leukemia were the respiratory organs, and the digestive organs. Under the linear hypothesis, which is far from proved for any form of cancer, except perhaps leukemia in Hiroshima, the estimated absolute risk for all forms of cancer, including leukemia, would suggest that the A-bomb survivor population of 285,000 registrants at the time of the 1950 census may have experienced 400 or 500 deaths from cancer induced by radiation in addition to perhaps 69,000 naturally occurring deaths in the interval 1950-74. (author)

  7. "Life-span development of visual working memory: When is feature binding difficult?": Correction to Cowan et al. (2006).

    Science.gov (United States)

    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

  8. [Genome loses all 5-methylcytosine a life span. How is this connected with accumulation of mutations during aging?].

    Science.gov (United States)

    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

  9. Lipopolysaccharide-induced inflammation attenuates taste progenitor cell proliferation and shortens the life span of taste bud cells

    Directory of Open Access Journals (Sweden)

    Brand Joseph

    2010-06-01

    Full Text Available Abstract Background The mammalian taste bud, a complex collection of taste sensory cells, supporting cells, and immature basal cells, is the structural unit for detecting taste stimuli in the oral cavity. Even though the cells of the taste bud undergo constant turnover, the structural homeostasis of the bud is maintained by balancing cell proliferation and cell death. Compared with nongustatory lingual epithelial cells, taste cells express higher levels of several inflammatory receptors and signalling proteins. Whether inflammation, an underlying condition in some diseases associated with taste disorders, interferes with taste cell renewal and turnover is unknown. Here we report the effects of lipopolysaccharide (LPS-induced inflammation on taste progenitor cell proliferation and taste bud cell turnover in mouse taste tissues. Results Intraperitoneal injection of LPS rapidly induced expression of several inflammatory cytokines, including tumor necrosis factor (TNF-α, interferon (IFN-γ, and interleukin (IL-6, in mouse circumvallate and foliate papillae. TNF-α and IFN-γ immunoreactivities were preferentially localized to subsets of cells in taste buds. LPS-induced inflammation significantly reduced the number of 5-bromo-2'-deoxyuridine (BrdU-labeled newborn taste bud cells 1-3 days after LPS injection, suggesting an inhibition of taste bud cell renewal. BrdU pulse-chase experiments showed that BrdU-labeled taste cells had a shorter average life span in LPS-treated mice than in controls. To investigate whether LPS inhibits taste cell renewal by suppressing taste progenitor cell proliferation, we studied the expression of Ki67, a cell proliferation marker. Quantitative real-time RT-PCR revealed that LPS markedly reduced Ki67 mRNA levels in circumvallate and foliate epithelia. Immunofluorescent staining using anti-Ki67 antibodies showed that LPS decreased the number of Ki67-positive cells in the basal regions surrounding circumvallate taste buds

  10. Lipopolysaccharide-induced inflammation attenuates taste progenitor cell proliferation and shortens the life span of taste bud cells.

    Science.gov (United States)

    Cohn, Zachary J; Kim, Agnes; Huang, Liquan; Brand, Joseph; Wang, Hong

    2010-06-10

    The mammalian taste bud, a complex collection of taste sensory cells, supporting cells, and immature basal cells, is the structural unit for detecting taste stimuli in the oral cavity. Even though the cells of the taste bud undergo constant turnover, the structural homeostasis of the bud is maintained by balancing cell proliferation and cell death. Compared with nongustatory lingual epithelial cells, taste cells express higher levels of several inflammatory receptors and signalling proteins. Whether inflammation, an underlying condition in some diseases associated with taste disorders, interferes with taste cell renewal and turnover is unknown. Here we report the effects of lipopolysaccharide (LPS)-induced inflammation on taste progenitor cell proliferation and taste bud cell turnover in mouse taste tissues. Intraperitoneal injection of LPS rapidly induced expression of several inflammatory cytokines, including tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, and interleukin (IL)-6, in mouse circumvallate and foliate papillae. TNF-alpha and IFN-gamma immunoreactivities were preferentially localized to subsets of cells in taste buds. LPS-induced inflammation significantly reduced the number of 5-bromo-2'-deoxyuridine (BrdU)-labeled newborn taste bud cells 1-3 days after LPS injection, suggesting an inhibition of taste bud cell renewal. BrdU pulse-chase experiments showed that BrdU-labeled taste cells had a shorter average life span in LPS-treated mice than in controls. To investigate whether LPS inhibits taste cell renewal by suppressing taste progenitor cell proliferation, we studied the expression of Ki67, a cell proliferation marker. Quantitative real-time RT-PCR revealed that LPS markedly reduced Ki67 mRNA levels in circumvallate and foliate epithelia. Immunofluorescent staining using anti-Ki67 antibodies showed that LPS decreased the number of Ki67-positive cells in the basal regions surrounding circumvallate taste buds, the niche for taste progenitor

  11. The concept of homology as a basis for evaluating developmental mechanisms: exploring selective attention across the life-span.

    Science.gov (United States)

    Lickliter, Robert; Bahrick, Lorraine E

    2013-01-01

    Research with human infants as well as non-human animal embryos and infants has consistently demonstrated the benefits of intersensory redundancy for perceptual learning and memory for redundantly specified information during early development. Studies of infant affect discrimination, face discrimination, numerical discrimination, sequence detection, abstract rule learning, and word comprehension and segmentation have all shown that intersensory redundancy promotes earlier detection of these properties when compared to unimodal exposure to the same properties. Here we explore the idea that such intersensory facilitation is evident across the life-span and that this continuity is an example of a developmental behavioral homology. We present evidence that intersensory facilitation is most apparent during early phases of learning for a variety of tasks, regardless of developmental level, including domains that are novel or tasks that require discrimination of fine detail or speeded responses. Under these conditions, infants, children, and adults all show intersensory facilitation, suggesting a developmental homology. We discuss the challenge and propose strategies for establishing appropriate guidelines for identifying developmental behavioral homologies. We conclude that evaluating the extent to which continuities observed across development are homologous can contribute to a better understanding of the processes of development. Copyright © 2012 Wiley Periodicals, Inc.

  12. A review of methionine dependency and the role of methionine restriction in cancer growth control and life-span extension.

    Science.gov (United States)

    Cavuoto, Paul; Fenech, Michael F

    2012-10-01

    Methionine is an essential amino acid with many key roles in mammalian metabolism such as protein synthesis, methylation of DNA and polyamine synthesis. Restriction of methionine may be an important strategy in cancer growth control particularly in cancers that exhibit dependence on methionine for survival and proliferation. Methionine dependence in cancer may be due to one or a combination of deletions, polymorphisms or alterations in expression of genes in the methionine de novo and salvage pathways. Cancer cells with these defects are unable to regenerate methionine via these pathways. Defects in the metabolism of folate may also contribute to the methionine dependence phenotype in cancer. Selective killing of methionine dependent cancer cells in co-culture with normal cells has been demonstrated using culture media deficient in methionine. Several animal studies utilizing a methionine restricted diet have reported inhibition of cancer growth and extension of a healthy life-span. In humans, vegan diets, which can be low in methionine, may prove to be a useful nutritional strategy in cancer growth control. The development of methioninase which depletes circulating levels of methionine may be another useful strategy in limiting cancer growth. The application of nutritional methionine restriction and methioninase in combination with chemotherapeutic regimens is the current focus of clinical studies. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Life span prediction from the rate of age-related DNA demethylation in normal and cancer cell lines.

    Science.gov (United States)

    Mazin, A L

    1995-01-01

    A method has been proposed for the Hayflick Limit prediction by the analysis of the 5-methylcytosine content in DNA at earlier and later cell passages. The following facts were used as the basis of the method: (i) the rate of m5C loss from DNA remains approximately constant during cell divisions and it does not depend on the cell donor age; (ii) this rate is inversely proportional to the Hayflick Limit as well as to the life span of cell donor species; (iii) the period corresponded to loss of all m5C residues from the genome coincides with or somewhat exceeds the Hayflick Limit of normal cells. The prognosis of the Hayflick Limit has usually been found in good agreement with the experimental evidences for various human, hamster, and mouse cell lines. The method proposed may be used for early detection of precrisis and cancer cells. The age-related m5C loss may result from accumulation of the m5C-->T+C transitions occurring with DNA methylation in every cell division.

  14. The Importance of Leisure Activities in the Relationship between Physical Health and Well-Being in a Life Span Sample.

    Science.gov (United States)

    Paggi, Michelle E; Jopp, Daniela; Hertzog, Christopher

    2016-01-01

    Previous studies have examined the relationships between physical health and leisure activities and between leisure activities and well-being, but, to our knowledge, none has examined these relationships simultaneously. This study investigated the relationships between leisure activities, health and well-being considering the role of age, and whether leisure activities mediate the relationship between physical health and well-being. Utilizing a cross-sectional database of 259 adults (ages 18-81 years) who completed several questionnaires, linear regression models and mediation models were tested. Regression analyses indicated that physical health was related to leisure activities and leisure activities were related to well-being. When physical health was measured by subjective ratings, age had a stronger relationship with leisure activities. However, when physical health was indicated by health restrictions, physical health had a stronger relationship with leisure activities than did age. Leisure activities were a partial mediator of the relationship between physical health and well-being. The results demonstrated that the reduction in leisure activities with age has more to do with physical health limitations than with older age itself. In addition, regardless of age, the benefits of physical health for well-being are due in part to the level of leisure activity participation. These results highlight the importance of leisure activities for successful aging throughout the adult life span. Interventions designed to improve well-being through increasing leisure activity participation should take physical health into consideration, particularly for older adults. © 2016 S. Karger AG, Basel.

  15. The ALS-associated proteins FUS and TDP-43 function together to affect Drosophila locomotion and life span

    Science.gov (United States)

    Wang, Ji-Wu; Brent, Jonathan R.; Tomlinson, Andrew; Shneider, Neil A.; McCabe, Brian D.

    2011-01-01

    The fatal adult motor neuron disease amyotrophic lateral sclerosis (ALS) shares some clinical and pathological overlap with frontotemporal dementia (FTD), an early-onset neurodegenerative disorder. The RNA/DNA-binding proteins fused in sarcoma (FUS; also known as TLS) and TAR DNA binding protein-43 (TDP-43) have recently been shown to be genetically and pathologically associated with familial forms of ALS and FTD. It is currently unknown whether perturbation of these proteins results in disease through mechanisms that are independent of normal protein function or via the pathophysiological disruption of molecular processes in which they are both critical. Here, we report that Drosophila mutants in which the homolog of FUS is disrupted exhibit decreased adult viability, diminished locomotor speed, and reduced life span compared with controls. These phenotypes were fully rescued by wild-type human FUS, but not ALS-associated mutant FUS proteins. A mutant of the Drosophila homolog of TDP-43 had similar, but more severe, deficits. Through cross-rescue analysis, we demonstrated that FUS acted together with and downstream of TDP-43 in a common genetic pathway in neurons. Furthermore, we found that these proteins associated with each other in an RNA-dependent complex. Our results establish that FUS and TDP-43 function together in vivo and suggest that molecular pathways requiring the combined activities of both of these proteins may be disrupted in ALS and FTD. PMID:21881207

  16. How much should we weigh for a long and healthy life span?The need to reconcile caloric restriction versus longevity with body mass index versus mortality data.

    Directory of Open Access Journals (Sweden)

    Antonello eLorenzini

    2014-07-01

    Full Text Available Total caloric restriction (CR without malnutrition is a well-established experimental approach to extend life span in laboratory animals. Although CR in humans is capable of shifting several endocrinological parameters it is not clear where the minimum inflection point of the U shaped curve linking body mass index (BMI with all-cause mortality lies. The exact trend of this curve, when used for planning preventive strategies for public health is of extreme importance. Normal BMI ranges from 18.5 to 24.9; many epidemiological studies show an inverse relationship between mortality and BMI inside the normal BMI range. Other studies show that the lowest mortality in the entire range of BMI is obtained in the overweight range (25 to 29.9. Reconciling the extension of life span in laboratory animals by experimental CR with the BMI-mortality curve of human epidemiology is not trivial. In fact, one interpretation is that the CR data are identifying a known: excess fat is deleterious for health; although a second interpretation may be that: additional leanness from a normal body weight may add health and life span delaying the process of aging. This short review hope to start a discussion aimed at finding the widest consensus on which weight range should be consider the healthiest for our species, contributing in this way to the picture of what is the correct life style for a long and healthy life span.

  17. Boundary Spanning

    DEFF Research Database (Denmark)

    Zølner, Mette

    The paper explores how locals span boundaries between corporate and local levels. The aim is to better comprehend potentialities and challenges when MNCs draws on locals’ culture specific knowledge. The study is based on an in-depth, interpretive case study of boundary spanning by local actors in...... approach with pattern matching is a way to shed light on the tacit local knowledge that organizational actors cannot articulate and that an exclusively inductive research is not likely to unveil....

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

    Directory of Open Access Journals (Sweden)

    Koella Jacob C

    2009-03-01

    Full Text Available Abstract 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.

  19. dSir2 in the Adult Fat Body, but Not in Muscles, Regulates Life Span in a Diet-Dependent Manner

    Directory of Open Access Journals (Sweden)

    Kushal Kr. Banerjee

    2012-12-01

    Full Text Available Sir2, an evolutionarily conserved NAD+-dependent deacetylase, has been implicated as a key factor in mediating organismal life span. However, recent contradictory findings have brought into question the role of Sir2 and its orthologs in regulating organismal longevity. In this study, we report that Drosophila Sir2 (dSir2 in the adult fat body regulates longevity in a diet-dependent manner. We used inducible Gal4 drivers to knock down and overexpress dSir2 in a tissue-specific manner. A diet-dependent life span phenotype of dSir2 perturbations (both knockdown and overexpression in the fat body, but not muscles, negates the effects of background genetic mutations. In addition to providing clarity to the field, our study contrasts the ability of dSir2 in two metabolic tissues to affect longevity. We also show that dSir2 knockdown abrogates fat-body dFOXO-dependent life span extension. This report highlights the importance of the interplay between genetic factors and dietary inputs in determining organismal life spans.

  20. Is the thrombopoietin assay useful for differential diagnosis of thrombocytopenia? Analysis of a cohort of 160 patients with thrombocytopenia and defined platelet life span.

    Science.gov (United States)

    Gouin-Thibault, I; Cassinat, B; Chomienne, C; Rain, J D; Najean, Y; Schlageter, M H

    2001-09-01

    Thrombopoietin (TPO), the major hormone controlling platelet production, has been measured in thrombocytopenias with discordant results. The aim of our work was to assess the value of the TPO assay for differential diagnosis of thrombocytopenias in a large cohort of patients classified according to the results of their platelet isotopic study. We measured TPO (R&D Systems) in serum of 160 thrombocytopenic patients referred to our department for platelet life span isotopic studies. We classified patients as follows: (a) idiopathic or autoimmune thrombocytopenia group (ITP; patients with increased platelet destruction and shortened platelet life span; n = 67); (b) pure genetic thrombocytopenia group (patients with decreased platelet production, normal platelet life span, and without bone marrow aplasia; n = 55); (c) bone marrow aplasia group (BM; patients with decreased platelet production, normal platelet life span, and bone marrow aplasia; n = 13). In patients with pure genetic thrombocytopenia, TPO (median, 55 ng/L) was not different from TPO in patients with ITP (median, 58 ng/L) or controls (n = 54; median, 51 ng/L). Only in patients with bone marrow aplasia was TPO significantly higher (median, 155 ng/L) and negatively correlated to the platelet count (r(2) = 0.5014). Although the median serum TPO is increased in thrombocytopenia with decreased platelet production from bone marrow aplasia, it does not differentiate patients with pure genetic thrombocytopenia from those with ITP.

  1. Developmental and age-specific effects of selection on divergent virgin life span on fat content and starvation resistance in Drosophila melanogaster

    NARCIS (Netherlands)

    Vermeulen, Cornelis; Van de Zande, Louis; Bijlsma, R.

    Investigations into the genetic basis of longevity variation have shown life span to be positively correlated with starvation resistance and negatively with female fecundity, both of which rely on lipid content. To assess the firmness of this relation, we assayed correlated responses in age-specific

  2. Pervasive gene expression responses to a fluctuating diet in Drosophila melanogaster: The importance of measuring multiple traits to decouple potential mediators of life span and reproduction.

    Science.gov (United States)

    Zandveld, Jelle; van den Heuvel, Joost; Mulder, Maarten; Brakefield, Paul M; Kirkwood, Thomas B L; Shanley, Daryl P; Zwaan, Bas J

    2017-11-01

    Phenotypic plasticity is an important concept in life-history evolution, and most organisms, including Drosophila melanogaster, show a plastic life-history response to diet. However, little is known about how these life-history responses are mediated. In this study, we compared adult female flies fed an alternating diet (yoyo flies) with flies fed a constant low (CL) or high (CH) diet and tested how whole genome expression was affected by these diet regimes and how the transcriptional responses related to different life-history traits. We showed that flies were able to respond quickly to diet fluctuations throughout life span by drastically changing their transcription. Importantly, by measuring the response of multiple life-history traits we were able to decouple groups of genes associated with life span or reproduction, life-history traits that often covary with a diet change. A coexpression network analysis uncovered which genes underpin the separate and shared regulation of these life-history traits. Our study provides essential insights to help unravel the genetic architecture mediating life-history responses to diet, and it shows that the flies' whole genome transcription response is highly plastic. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  3. JNIH-ABCC Life Span Study. Report 2. Mortality in selection I and II, October 1950-September 1959

    Energy Technology Data Exchange (ETDEWEB)

    Jablon, S; Ishida, Morihiro; Beebe, G W

    1963-01-23

    The present JNIH-ABCC Life Span Study is based on a sample of about 100,000 persons consisting of survivors 0 to 2499m of the hypocenter together with persons more distally located and persons not present in either city ATB. Followup is maintained by consulting official family registers kept by local authorities in Japan. Mortality rates calculated from the present data agree fairly well with Japanese national rates for 1955. Total mortality rates are not grossly different between survivors who were located at various distances, but nonexposed persons, especially males, have much lower mortality rates than do survivors. This difference is attributable to much lower mortality from tuberculosis. Leukemia mortality rates calculated from the present data confirm the well known facts as to the leukemogenic effects of radiation from the atomic bombs on survivors. Mortality from malignant neoplasms other than leukemia found by the present study differs in major ways from what would be expected from data of the Hiroshima Tumor Registry previously published by Harada and Ishida. Instead of a general increase of rather large magnitude in tumors of all sites among heavily irradiated survivors, an effect of moderate magnitude (though quite definite) is found among Hiroshima females. Among survivors nearest the hypocenter no convincing evidence was found of elevation in mortality rates for natural causes exclusive of neoplasms. Definitely increased death rates for aplastic anemia were found, especially in Nagasaki. This probably results from diagnostic difficulties in distinguishing between this disease and leukemia. Mortality from tuberculosis was elevated among male survivors 0 to 1399m in both cities, but especially in Hiroshima. 13 references, 14 figures, 16 tables.

  4. Evaluation of platelet thromboxane radioimmunoassay method to measure platelet life-span: Comparison with /sup 111/indium-platelet method

    International Nuclear Information System (INIS)

    Vallabhajosula, S.; Machac, J.; Badimon, L.; Lipszyc, H.; Goldsmith, S.J.; Fuster, V.

    1985-01-01

    The platelet activation during radiolabeling in vitro with Cr-51 and In-111 may affect the platelet life-span (PLS) in vivo. A new RIA method to measure PLS is being evaluated. Aspirin inhibits platelet thromboxane (TxA/sub 2/) by acetylating cyclooxygenase. The time required for the TxA/sub 2/ levels to return towards control values depends on the rate of new platelets entering circulation and is a measure of PLS. A single dose of aspirin (150mg) was given to 5 normal human subjects. Blood samples were collected for 2 days before aspirin and daily for 10 days. TxA/sub 2/ production in response to endogenous thrombin was studied by allowing 1 ml blood sample to clot at 37 0 C for 90 min. Serum TxB/sub 2/ (stable breakdown product of Tx-A/sub 2/) levels determined by RIA technique. The plot of TxB/sub 2/ levels (% control) against time showed a gradual increase. The PLS calculated by linear regression analysis assuming a 2-day lag period before cyclooxygenase recovery is 9.7 +- 2.37. In the same 5 subjects, platelets from a 50ml blood sample were labeled with /sup 111/In-tropolone in 2 ml autologous plasma. Starting at 1 hr after injection of labeled platelets, 10 blood samples were obtained over a 8 day period. The PLS calculated based on a linear regression analysis is 10.2 +. 1.4. The PLS measured from the rate of platelet disappearance from circulation and the rate of platelet regeneration into circulation are quite comparable in normal subjects. TxA/sub 2/ regeneration RIA may provide a method to measure PLS without administering radioactivity to patient

  5. Life span study report 11. part 3. noncancer mortality, 1950-85, based on the revised doses (DS86)

    International Nuclear Information System (INIS)

    Shimizu, Yukiko; Kato, Hiroo; Schull, W.J.; Hoel, D.G.

    1993-01-01

    Deaths in the RERF Life Span Study (LSS) sample have been determined for the years 1950-85 and previous reports have described analyses of cancer mortality using the revised Dosimetry System 1986 (DS86) doses (LSS Report 11, Parts 1 and 2). In this report, we examine the relationship to dose of deaths from all diseases other than cancer. Although the evidence is still limited, there seems to be an excess risk for noncancer death at high doses (2 or 3 Gy and over). Statistically, a pure quadratic or a linear-threshold model (the estimated threshold dose is 1.4 Gy [0.6-2.8 Gy] is found to fit better than a simple linear or linear-quadratic model. This increase in noncancer mortality is statistically demonstrable, generally, after 1965 and among the younger survivors (< 40) at the time of the bombings, suggesting a sensitivity in this age group. For specific causes of death, an excess relative risk at the high dose level, that is, ≥ 2 Gy, is seen in circulatory and digestive diseases. The relative risk is, however, much smaller than that for cancer. These findings, based as they are on death certificates, have their limitations. Most significant, perhaps, is the possible erroneous attribution of radiation-related cancer deaths to other causes. At present, the contribution such errors may make to the apparent increase in noncancer deaths at the high doses cannot be estimated as rigorously as is obviously desirable. However, even now, this increase does not appear to be fully explicable in terms of classificatory errors. (J.P.N.)

  6. Body size, growth and life span: implications for the polewards range shift of Octopus tetricus in south-eastern Australia.

    Science.gov (United States)

    Ramos, Jorge E; Pecl, Gretta T; Moltschaniwskyj, Natalie A; Strugnell, Jan M; León, Rafael I; Semmens, Jayson M

    2014-01-01

    Understanding the response of any species to climate change can be challenging. However, in short-lived species the faster turnover of generations may facilitate the examination of responses associated with longer-term environmental change. Octopus tetricus, a commercially important species, has undergone a recent polewards range shift in the coastal waters of south-eastern Australia, thought to be associated with the southerly extension of the warm East Australian Current. At the cooler temperatures of a polewards distribution limit, growth of a species could be slower, potentially leading to a bigger body size and resulting in a slower population turnover, affecting population viability at the extreme of the distribution. Growth rates, body size, and life span of O. tetricus were examined at the leading edge of a polewards range shift in Tasmanian waters (40°S and 147°E) throughout 2011. Octopus tetricus had a relatively small body size and short lifespan of approximately 11 months that, despite cooler temperatures, would allow a high rate of population turnover and may facilitate the population increase necessary for successful establishment in the new extended area of the range. Temperature, food availability and gender appear to influence growth rate. Individuals that hatched during cooler and more productive conditions, but grew during warming conditions, exhibited faster growth rates and reached smaller body sizes than individuals that hatched into warmer waters but grew during cooling conditions. This study suggests that fast growth, small body size and associated rapid population turnover may facilitate the range shift of O. tetricus into Tasmanian waters.

  7. Effects of PPP1R1B (DARPP-32 Polymorphism on Feedback-related Brain Potentials across the Life Span

    Directory of Open Access Journals (Sweden)

    Dorothea eHämmerer

    2013-03-01

    Full Text Available Maximizing gains during probabilistic reinforcement learning requires the updating of choice–outcome expectations at the time when the feedback about a specific choice or action is given. Extant theories and evidence suggest that dopaminergic modulation plays a crucial role in reinforcement learning and the updating of choice–outcome expectations. Furthermore, recently a positive component of the event-related potential (ERP about 200 msec (P2 after feedback has been suggested to reflect such updating. The efficacy of dopaminergic modulation changes across the life span. However, to date investigations of age-related differences in feedback-related P2 during reinforcement learning are still scarce. The present study thus aims to investigate whether individual differences in the feedback-related P2 would be associated with polymorphic variations in a dopamine relevant gene PPP1R1B (also known as DARPP-32 and whether the genetic effect may differ between age groups. We observed larger P2 amplitudes in individuals carrying the genotype associated with higher dopamine receptor efficacy, i.e., A allele homozygotes of a single nucleotide polymorphism (rs907094 of the PPP1R1B gene. Moreover, this effect was more pronounced in children and older adults in comparison to adolescents and younger adults. Together, our findings indicate that polymorphic variations in a dopamine relevant gene are associated with individual differences in brain-evoked potentials of outcome updating and hint at the possibility that genotype effects on neurocognitive phenotypes may vary as a function of brain maturation and aging.

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

    Science.gov (United States)

    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 morphological, chemical and metabolic traits.

  9. nfi-1 affects behavior and life-span in C. elegans but is not essential for DNA replication or survival

    Directory of Open Access Journals (Sweden)

    Hirono Keiko

    2005-10-01

    Full Text Available Abstract Background The Nuclear Factor I (one (NFI family of transcription/replication factors plays essential roles in mammalian gene expression and development and in adenovirus DNA replication. Because of its role in viral DNA replication NFI has long been suspected to function in host DNA synthesis. Determining the requirement for NFI proteins in mammalian DNA replication is complicated by the presence of 4 NFI genes in mice and humans. Loss of individual NFI genes in mice cause defects in brain, lung and tooth development, but the presence of 4 homologous NFI genes raises the issue of redundant roles for NFI genes in DNA replication. No NFI genes are present in bacteria, fungi or plants. However single NFI genes are present in several simple animals including Drosophila and C. elegans, making it possible to test for a requirement for NFI in multicellular eukaryotic DNA replication and development. Here we assess the functions of the single nfi-1 gene in C. elegans. Results C. elegans NFI protein (CeNFI binds specifically to the same NFI-binding site recognized by vertebrate NFIs. nfi-1 encodes alternatively-spliced, maternally-inherited transcripts that are expressed at the single cell stage, during embryogenesis, and in adult muscles, neurons and gut cells. Worms lacking nfi-1 survive but have defects in movement, pharyngeal pumping and egg-laying and have a reduced life-span. Expression of the muscle gene Ce titin is decreased in nfi-1 mutant worms. Conclusion NFI gene function is not needed for survival in C. elegans and thus NFI is likely not essential for DNA replication in multi-cellular eukaryotes. The multiple defects in motility, egg-laying, pharyngeal pumping, and reduced lifespan indicate that NFI is important for these processes. Reduction in Ce titin expression could affect muscle function in multiple tissues. The phenotype of nfi-1 null worms indicates that NFI functions in multiple developmental and behavioral systems in C

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

    Science.gov (United States)

    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.

  11. Effect of chlorella and its fractions on blood pressure, cerebral stroke lesions, and life-span in stroke-prone spontaneously hypertensive rats.

    Science.gov (United States)

    Sansawa, Hiroshi; Takahashi, Masatoshi; Tsuchikura, Satoru; Endo, Hiroshi

    2006-12-01

    Effects of Chlorella regularis (dried cell powder)--cultured axenically under heterotrophic conditions, and provided as a dietary supplement--and its fractions on the blood pressure, cerebral stroke lesions, and life-span of stroke-prone spontaneously hypertensive rats (SHRSP/Izm) were investigated. When SHRSP were fed on diets with supplemented Chlorella to a commercial diet (Funabashi SP), elevation of blood pressure was significantly lower in the Chlorella groups than in the control group. At 21 wk of feeding, serum total cholesterol was significantly lower in the Chlorella groups than in the control group. Histopathological examination revealed cerebral vascular accidents in the brains of the control group, but those of Chlorella groups showed apparently low incidence compared to the control group. The average life-span of the Chlorella groups were significantly longer than that of the control group (p vascular function of rats.

  12. Regularity of mortality and life span of the experimental animals under the exposure of protracted internal irradiation with radionuclides of 137Cs and 90Sr

    International Nuclear Information System (INIS)

    Yindik, V.M.; Serkyiz, Ya.Yi.; Lips'ka, A.Yi.; Alyistratov, O.V.; Drozd, Yi.P.; Gerasimova, T.B.; Dudchenko, T.M.

    2002-01-01

    It has been shown that exposure to protracted low intense irradiation with low doses, caused by radionuclides ( 137 Cs and 90 Sr) has negative influence on survival indices and expected life span in different groups according to age. Mortality of irradiated animals is mainly caused by development of pathological processes of tumor origin. The frequency of radiation induced tumors is the same with intact control

  13. The T?lz Temporal Topography Study: Mapping the visual field across the life span. Part II: Cognitive factors shaping visual field maps

    OpenAIRE

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

    2012-01-01

    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, an...

  14. Ectopic hTERT expression extends the life span of human CD4(+) helper and regulatory T-cell clones and confers resistance to oxidative stress-induced apoptosis

    NARCIS (Netherlands)

    Luiten, Rosalie M.; Péne, Jérome; Yssel, Hans; Spits, Hergen

    2003-01-01

    Human somatic cells have a limited life span in vitro. Upon aging and with each cell division, shortening of telomeres occurs, which eventually will lead to cell cycle arrest. Ectopic hTERT expression has been shown to extend the life span of human T cells by preventing this telomere erosion. In the

  15. Life-Cycle Monitoring of Long-Span PSC Box Girder Bridges through Distributed Sensor Network: Strategies, Methods, and Applications

    OpenAIRE

    Chen, Zheheng; Guo, Tong; Yan, Shengyou

    2015-01-01

    Structural health monitoring (SHM) has attracted much attention in recent years, which enables early warnings of structural failure, condition assessments, and rational maintenance/repair strategies. In the context of bridges, many long-span steel bridges in China have been installed with the SHM systems; however, the applications of the SHM in prestressed concrete (PSC) bridges are still rather limited. On the other hand, the PSC box girder bridges are extensively used in highway and railway...

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  19. The Eyring-Stover theory of survival applied to life-span radiation effects studies in animals

    International Nuclear Information System (INIS)

    Stover, B.J.; Wrenn, M.E.; Jee, W.S.S.; Atherton, D.R.

    1986-01-01

    The Eyring-Stover theory of survival describes the observed biological phenomena of damage and repair as steady-state processes that can be expressed in the formalism of absolute reaction rate theory. The steady-state formulation, rather than that of dynamic equilibrium, is invoked since biological phenomena, in contrast with most chemical and physical phenemena, are time irreversible. The theory is appropriate for calculating life shortening that results from environmental factors such as irradiation since it does not require universality and intrinsicality as to some theories of aging. The theory gives not only midrange mortality rate values but also end-range values, which are difficult to predict empirically. The previously calculated life shortening of mice after external x-irradiation and of beagles after internal irradiation from 239 Pu or 226 Ra is reviewed; life shortening at low dose levels of 226 Ra is presented. 21 refs., 1 tab

  20. Chronology. Classroom Focus.

    Science.gov (United States)

    McGoldrick, Neale

    1995-01-01

    Presents a chronology of important dates and events in the struggle for women's rights and women's suffrage. Begins in 1648 with the first call for women's suffrage in Maryland and concludes in 1920 with the passage of the 19th Amendment by Tennessee. (CFR)

  1. 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

    Science.gov (United States)

    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.

  2. Dmp53, basket and drICE gene knockdown and polyphenol gallic acid increase life span and locomotor activity in a Drosophila Parkinson's disease model

    Directory of Open Access Journals (Sweden)

    Hector Flavio Ortega-Arellano

    2013-01-01

    Full Text Available Understanding the mechanism(s by which dopaminergic (DAergic neurons are eroded in Parkinson's disease (PD is critical for effective therapeutic strategies. By using the binary tyrosine hydroxylase (TH-Gal4/UAS-X RNAi Drosophila melanogaster system, we report that Dmp53, basket and drICE gene knockdown in dopaminergic neurons prolong life span (p < 0.05; log-rank test and locomotor activity (p < 0.05; χ² test in D. melanogaster lines chronically exposed to (1 mM paraquat (PQ, oxidative stress (OS generator compared to untreated transgenic fly lines. Likewise, knockdown flies displayed higher climbing performance than control flies. Amazingly, gallic acid (GA significantly protected DAergic neurons, ameliorated life span, and climbing abilities in knockdown fly lines treated with PQ compared to flies treated with PQ only. Therefore, silencing specific gene(s involved in neuronal death might constitute an excellent tool to study the response of DAergic neurons to OS stimuli. We propose that a therapy with antioxidants and selectively "switching off" death genes in DAergic neurons could provide a means for pre-clinical PD individuals to significantly ameliorate their disease condition.

  3. The influence of superoxide dimutase and some other radical scavengers on X-ray resistance, life span and membrane integrity of Sacharomyces cerevisiae

    International Nuclear Information System (INIS)

    Hartwig, V.

    1988-01-01

    Evaluations of various strains of yeast showed these to differ widely in the activities of superoxide dimutase and catalase, X-ray sensitivity, reproductive capacity and malondialdehyde concentration. Higher SOD activities in reponse to increases in oxygen production under extreme physiological conditions were observed for the cells of a haploid strain and just as well seen in those of a diploid strain. There were findings pointing to mutually 'compensatory' effects in respect of the contents of CAT and thiol. When intracellular radical scavengers were 'overstrained' by exposure to high X-ray doses, untoward effects on membrane integrity could be detected after irradiation. The use of the SOD-specific inhibitor DDC led to a reduction of both X-ray resistance and life span as a result of SOD-inhibition. Exogenous SOD was seen to reduce the mean life span. Cu 2+ and Mn 2+ were found to have a dual action in that they not only increased the resistance to X-rays through an augmentation of SOD activity but also had an immediate beneficial effect on radioresistance. Exogenous H202 led to an increase in the cellular CAT contents and an enhancement of X-ray resistance. (orig./MG) [de

  4. The use of fractal dimension calculation algorithm to determine the nature of autobiographical memories distribution across the life span

    Science.gov (United States)

    Mitina, Olga V.; Nourkova, Veronica V.

    In the given research we offer the technique for the calculation of the density of events which people retrieve from autobiographical memory. We wanted to prove a non-uniformity nature of memories distribution in the course of time and were interested with the law of distribution of these events during life course.

  5. Aspartame administered in feed, beginning prenatally through life span, induces cancers of the liver and lung in male Swiss mice.

    Science.gov (United States)

    Soffritti, Morando; Belpoggi, Fiorella; Manservigi, Marco; Tibaldi, Eva; Lauriola, Michelina; Falcioni, Laura; Bua, Luciano

    2010-12-01

    Aspartame (APM) is a well-known intense artificial sweetener used in more than 6,000 products. Among the major users of aspartame are children and women of childbearing age. In previous lifespan experiments conducted on Sprague-Dawley rats we have shown that APM is a carcinogenic agent in multiple sites and that its effects are increased when exposure starts from prenatal life. The aim of this study is to evaluate the potential of APM to induce carcinogenic effects in mice. Six groups of 62-122 male and female Swiss mice were treated with APM in feed at doses of 32,000, 16,000, 8,000, 2,000, or 0  ppm from prenatal life (12 days of gestation) until death. At death each animal underwent complete necropsy and all tissues and organs of all animals in the experiment were microscopically examined. APM in our experimental conditions induces in males a significant dose-related increased incidence of hepatocellular carcinomas (P < 0.01), and a significant increase at the dose levels of 32,000  ppm (P < 0.01) and 16,000  ppm (P < 0.05). Moreover, the results show a significant dose-related increased incidence of alveolar/bronchiolar carcinomas in males (P < 0.05), and a significant increase at 32,000  ppm (P < 0.05). The results of the present study confirm that APM is a carcinogenic agent in multiple sites in rodents, and that this effect is induced in two species, rats (males and females) and mice (males). No carcinogenic effects were observed in female mice. Am. J. Ind. Med. 53:1197-1206, 2010. © 2010 Wiley-Liss, Inc.

  6. Absolute chronology and stratigraphy of Lepenski Vir

    Directory of Open Access Journals (Sweden)

    Borić Dušan

    2007-01-01

    Full Text Available In the last decade, a number of specialist analyses were made on the material from old excavations of Mesolithic-Neolithic sites in the Danube Gorges. These new results altered significantly our understanding of the Lepenski Vir culture. The question of chronology of this regional phenomenon has been acute since the discovery of Lepenski Vir in the 1960s, and it remains of key importance for understanding the character of Mesolithic-Neolithic transformations in this and the neighbouring regions. The most heated debate was fuelled by the initial stratigraphic and chronological attribution of the type-site itself. There remained the question about the adequate dating of the most prominent phase at this site characterized by buildings with trapezoidal bases covered with limestone floors and with rectangular stone-lined hearths placed in the centre of these features. There have been suggestions that these features also contain Early Neolithic Starčevo type pottery and other similar items of material culture and should thus be dated to the Early Neolithic historical context. Moreover, the first series of conventional radiocarbon determinations (21 dates also suggested that the absolute chronology of these features should be confined to the period from around 6400-5500 cal BC (Fig. 1. Due to the importance of defining more precisely the chronology for the start of construction of these particular features at Lepenski Vir and for establishing the life-span of these buildings and their associated material culture, we have AMS (Accelerator Mass Spectrometry dated a number of contexts from this site. The results are presented in this paper. The project was made possible through the Oxford Radiocarbon Accelerate Dating Service (ORADS programme funded by the Arts and Humanities Research Council (AHRC and the Natural Environment Research Council (NERC of the Great Britain. Apart from those dates presented in this paper, there are 29 previously published

  7. Age differences in big five behavior averages and variabilities across the adult life span: moving beyond retrospective, global summary accounts of personality.

    Science.gov (United States)

    Noftle, Erik E; Fleeson, William

    2010-03-01

    In 3 intensive cross-sectional studies, age differences in behavior averages and variabilities were examined. Three questions were posed: Does variability differ among age groups? Does the sizable variability in young adulthood persist throughout the life span? Do past conclusions about trait development, based on trait questionnaires, hold up when actual behavior is examined? Three groups participated: young adults (18-23 years), middle-aged adults (35-55 years), and older adults (65-81 years). In 2 experience-sampling studies, participants reported their current behavior multiple times per day for 1- or 2-week spans. In a 3rd study, participants interacted in standardized laboratory activities on 8 occasions. First, results revealed a sizable amount of intraindividual variability in behavior for all adult groups, with average within-person standard deviations ranging from about half a point to well over 1 point on 6-point scales. Second, older adults were most variable in Openness, whereas young adults were most variable in Agreeableness and Emotional Stability. Third, most specific patterns of maturation-related age differences in actual behavior were more greatly pronounced and differently patterned than those revealed by the trait questionnaire method. When participants interacted in standardized situations, personality differences between young adults and middle-aged adults were larger, and older adults exhibited a more positive personality profile than they exhibited in their everyday lives.

  8. ABCC-JNIH pathology studies, Hiroshima and Nagasaki. Report III. The autopsy program and the life span study, January 1951--December 1970

    Energy Technology Data Exchange (ETDEWEB)

    Steer, A; Moriyama, I M; Shimizu, K

    1973-01-01

    Of the 19,701 deaths in the Life Span cohort between 1951--70, 22% came to autopsy. The autopsy procurement rate reached 45% in 1963 and declined thereafter. Problems and bias are discussed; autopsy rates were directly associated with radiation dose, especially in Hiroshima. Favorable autopsy procurement rates did not result from the rapport with survivors in the Adult Health Study. A study was made of stroke, ischemic heart disease, and cancer. The occurrence of cancer by site and cell type agrees with other data from Japan except for those cancers associated with prior ionizing radiation. Estimated radiation exposure data reveals no significant association for any disease other than some forms of cancer. (45 tables) (DLC)

  9. An overview of a multifactor-system theory of personality and individual differences: III. Life span development and the heredity-environment issue.

    Science.gov (United States)

    Powell, A; Royce, J R

    1981-12-01

    In Part III of this three-part series on multifactor-system theory, multivariate, life-span development is approached from the standpoint of a quantitative and qualitative analysis of the ontogenesis of factors in each of the six systems. The pattern of quantitative development (described via the Gompertz equation and three developmental parameters) involves growth, stability, and decline, and qualitative development involves changes in the organization of factors (e.g., factor differentiation and convergence). Hereditary and environmental sources of variation are analyzed via the factor gene model and the concept of heredity-dominant factors, and the factor-learning model and environment-dominant factors. It is hypothesized that the sensory and motor systems are heredity dominant, that the style and value systems are environment dominant, and that the cognitive and affective systems are partially heredity dominant.

  10. The Tölz Temporal Topography Study: mapping the visual field across the life span. Part I: the topography of light detection and temporal-information processing.

    Science.gov (United States)

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

    2012-08-01

    Temporal performance parameters vary across the visual field. Their topographical distributions relative to each other and relative to basic visual performance measures and their relative change over the life span are unknown. Our goal was to characterize the topography and age-related change of temporal performance. We acquired visual field maps in 95 healthy participants (age: 10-90 years): perimetric thresholds, double-pulse resolution (DPR), reaction times (RTs), and letter contrast thresholds. DPR and perimetric thresholds increased with eccentricity and age; the periphery showed a more pronounced age-related increase than the center. RT increased only slightly and uniformly with eccentricity. It remained almost constant up to the age of 60, a marked change occurring only above 80. Overall, age was a poor predictor of functionality. Performance decline could be explained only in part by the aging of the retina and optic media. In Part II, we therefore examine higher visual and cognitive functions.

  11. Beliefs about age-related changes in physical functioning across the adult life span and their relationship with physical activity levels of older adults.

    Science.gov (United States)

    Lineweaver, Tara T; Kugler, Jennifer; Rabellino, Alessandra; Stephan, Yannick

    2018-07-01

    Physical activity declines across the adult life span despite the well-established links between physical activity and health-related, psychological, cognitive, and social benefits. We contrasted the beliefs young and older adults hold about how aging affects both physical abilities and physical activity and determined whether older adults' beliefs about physical aging relate to their engagement in physical activity. Using visual rating scales, 56 young and 49 community-dwelling older adults indicated the extent to which a typical woman or typical man aged 20-90 possesses six different physical abilities and engages in three different types of physical activity. Stereotypes of physical aging were ability- and activity-specific, and older adults endorsed more positive views than their younger peers. Stereotypical beliefs predicted older adults' engagement in moderate-intensity activity. This study offers intriguing avenues for future research and suggests that better understanding physical aging stereotypes may contribute toward designing interventions that promote lifelong physical activity.

  12. Kaposi's sarcoma-associated herpesvirus latency-associated nuclear antigen prolongs the life span of primary human umbilical vein endothelial cells.

    Science.gov (United States)

    Watanabe, Takahiro; Sugaya, Makoto; Atkins, April M; Aquilino, Elisabeth A; Yang, Aparche; Borris, Debra L; Brady, John; Blauvelt, Andrew

    2003-06-01

    Tumor spindle cells in all clinical types of Kaposi's sarcoma (KS) are infected with Kaposi's sarcoma-associated herpesvirus (KSHV). Although KSHV contains more than 80 genes, only a few are expressed in tumor spindle cells, including latency-associated nuclear antigen (LANA) and k-cyclin (kCYC). To assess the oncogenic potential of LANA and kCYC, primary human umbilical vein endothelial cells (HUVEC) and murine NIH 3T3 cells were stably transduced by using recombinant retroviruses expressing these genes or the known viral oncogene simian virus 40 large T antigen (LTAg). Interestingly, LANA-transduced HUVEC proliferated faster and demonstrated a greatly prolonged life span (mean +/- standard deviation, 38.3 +/- 11.0 passages) than untransduced cells and vector-transduced cells (<20 passages). By contrast, kCYC-transduced HUVEC did not proliferate faster or live longer than control cells. LANA- and kCYC-transduced HUVEC, but not LTAg-transduced HUVEC, retained the ability to form normal vessel-like structures in an in vitro model of angiogenesis. In cellular assays of transformation, LANA- and kCYC-transduced NIH 3T3 cells demonstrated minimal or no anchorage-independent growth in soft agar and no tumorigenicity when injected into nude mice, unlike LTAg-transduced NIH 3T3 cells. Lastly, gene expression profiling revealed down-regulation, or silencing, of a number of genes within LANA-transduced HUVEC. Taken together, these results suggest that KSHV LANA is capable of inducing prolonged life span, but not transformation, in primary human cells. These findings may explain why LANA-expressing spindle cells proliferate within KS tumors, yet most often do not demonstrate biologic characteristics of transformation or true malignant conversion.

  13. Changes in gas exchange characteristics during the life span of giant sequoia: Implications for response to current and future concentrations of atmospheric ozone

    Energy Technology Data Exchange (ETDEWEB)

    Grulke, N.E.; Miller, P.R. (USDA Forest Service, Riverside, CA (United States))

    Native stands of giant sequoia are being exposed to relatively high concentrations of atmospheric ozone produced in urban and agricultural areas upwind. The expected change in environmental conditions over the next 100 y is likely to be unprecendented in the life span (ca 2,500 y) of giant sequoia. Changes in the physiological responses of three age classes of giant sequoia (current year, 12 y and 25 y) to different concentrations of ozone were determined, and age-related differences in sensitivity to pollutants were assessed by examining physiological changes (gas exchange, water use efficiency) across the life span of giant sequoia. The CO[sub 2] exchange rate (CER) was greater in current year (12.1 [mu]mol CO[sub 2]/m[sup 2]s) and 2 year old seedlings (4.8 [mu]mol CO[sub 2]/m[sup 2]s) than in all older trees (average of 3.0 [mu]mol CO[sub 2]/m[sup 2]s). Dark respiration was highest for current year seedlings and was increased twofold in symptotic individuals exposed to elevated ozone concentrations. Stomatal conductance was greater in current-year and 2 year old seedlings (335 and 200 mmol H[sub 2]O/m[sup 2]s), respectively, than in all older trees (50 mmol H[sub 2]O/m[sup 2]s), indicating that the ozone concentration in substomatol cavities is higher in young seedlings than in older trees. Significant changes in water use efficiency occurred in trees between ages 5 and 20 years. It is concluded that giant sequoia seedlings are sensitive to atmospheric ozone until they are ca 5 y old. Low conductance, high water use efficiency, and compact mesophyll all contribute to a natural ozone tolerance, or defense, or both, in foliage of older trees. 11 refs., 1 fig., 1 tab.

  14. Study on Renal Anemia: A Double Tracer Study on Metabolism and Red Cell Life Span in Chronic Renal Diseases using Radioactive Iron (59Fe) and Chromium (51Cr)

    International Nuclear Information System (INIS)

    Jung, Kyung Tae; Lee, Mun Ho

    1968-01-01

    The ferrokinetics and red cell life spans of the patients with chronic glomerulonephritis were investigated by the double tracing method using radioactive iron ( 59 Fe) and chromium ( 51 Cr). According to the serum NPN levels, the patients were subdivided into 3 groups: Group 1. 6 patients, had the levels below 40 mg/dl. Group 2. 6 patients, had the levels between 41 mg/dl to 80 mg/dl. Group 3. 10 patients had the levels above 80 mg/dl. The results were as follows: 1) Red blood cell, hematocrit and hemoglobin values were moderately reduced in patients with normal serum NPN levels, while markedly reduced in patients with elevated serum NPN levels. 2) The plasma volume was increased, while the red cell volume was decreased in patients with elevated serum NPN levels, hence, total blood volume was unchanged. 3) The serum iron level was slightly reduced in patients of groups 1 and 2, while was within the normal ranges in patients of group 3. 4) i) In patients with normal serum NPN levels, the plasma iron disappearance rate, red cell iron utilization rate, red cell iron turnover rate, daily red cell iron renewal rate, circulating red cell iron and red cell iron concentration were within the normal ranges, while the plasma iron turnover rate was slightly reduced. ii) In patients with elevated serum NPN levels, the plasma iron disappearance rate was delayed, while the plasma iron turnover rate was within the normal ranges. The red cell iron utilization rate, red cell iron turnover rate and circulating red cell iron were decreased and the period in which the red cell iron utilization rate reached its peak was delayed in Group 3 patients. The daily red cell iron renewal rate and the red cell iron concentration were unchanged. iii) The mean red cell life span was within the normal ranges in patients with normal serum NPN levels, while was shortened in patients with elevated serum NPN levels.

  15. Nuclear cosmo-chronology

    International Nuclear Information System (INIS)

    Berkes, I.

    2002-01-01

    Nuclear cosmo-chronology is based on the age determination method by using pairs of isotopes or elements: 235 U / 238 U, 187 Re / 187 Os and Th / U or Th / Eu. In this article we examine the age of the galaxy that has been deduced from the analysis of meteorites or from the absorption spectra of the solar light and the age of old stars. Since the solar system is far younger than the galaxy, the evaluation based on the abundances of nuclei in the solar system (absorption spectra of the sun, abundance ratio on meteorites) should take into account a model of the chemistry evolution of the galaxy. The age of the galaxy appears to be somewhere between 12 and 15 Gy with an absolute error of 3 Gy. As for very old stars, they appear to be just a bit older than the galaxy so the evaluation of their age is independent from the chemical evolution of the galaxy. The formation of galaxies began 1 to 2 Gy after the big-bang, the nuclear cosmo-chronology gives the same age for the galaxy as cosmological considerations on the age of the universe do. (A.C.)

  16. Suicide: Across the Life Span.

    Science.gov (United States)

    Ramirez, Jeffery

    2016-06-01

    Suicide remains a major public health issue. There have been more than 40,000 deaths by suicide in 2014. Understanding both the neuroscience and psychological development is key for nursing care so adequate interventions and treatment strategies are developed when working with people thinking about suicide. It is critical to assess and recognize risk and protective factors to ensure patient safety. The older adult, children, and adolescent populations remain vulnerable to suicide. A discussion regarding the psychiatric, psychosocial, and treatment considerations for these populations is included. An overview of communication, suicide assessment, and safety planning is discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Life span in online communities

    Science.gov (United States)

    Grabowski, A.; Kosiński, R. A.

    2010-12-01

    Recently online communities have attracted great interest and have become an important medium of information exchange between users. The aim of this work is to introduce a simple model of the evolution of online communities. This model describes (a) the time evolution of users’ activity in a web service, e.g., the time evolution of the number of online friends or written posts, (b) the time evolution of the degree distribution of a social network, and (c) the time evolution of the number of active users of a web service. In the second part of the paper we investigate the influence of the users’ lifespan (i.e., the total time in which they are active in an online community) on the process of rumor propagation in evolving social networks. Viral marketing is an important application of such method of information propagation.

  18. Neuron-specific knockdown of the Drosophila fat induces reduction of life span, deficient locomotive ability, shortening of motoneuron terminal branches and defects in axonal targeting.

    Science.gov (United States)

    Nakamura, Aya; Tanaka, Ryo; Morishita, Kazushige; Yoshida, Hideki; Higuchi, Yujiro; Takashima, Hiroshi; Yamaguchi, Masamitsu

    2017-07-01

    Mutations in FAT4 gene, one of the human FAT family genes, have been identified in Van Maldergem syndrome (VMS) and Hennekam lymphangiectasia-lymphedema syndrome (HS). The FAT4 gene encodes a large protein with extracellular cadherin repeats, EGF-like domains and Laminin G-like domains. FAT4 plays a role in tumor suppression and planar cell polarity. Drosophila contains a human FAT4 homologue, fat. Drosophila fat has been mainly studied with Drosophila eye and wing systems. Here, we specially knocked down Drosophila fat in nerve system. Neuron-specific knockdown of fat shortened the life span and induced the defect in locomotive abilities of adult flies. In consistent with these phenotypes, defects in synapse structure at neuromuscular junction were observed in neuron-specific fat-knockdown flies. In addition, aberrations in axonal targeting of photoreceptor neuron in third-instar larvae were also observed, suggesting that fat involves in axonal targeting. Taken together, the results indicate that Drosophila fat plays an essential role in formation and/or maintenance of neuron. Both VMS and HS show mental retardation and neuronal defects. We therefore consider that these two rare human diseases could possibly be caused by the defect in FAT4 function in neuronal cells. © 2017 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

  19. Diet quality and cognitive function in an urban sample: findings from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study.

    Science.gov (United States)

    Wright, Regina S; Waldstein, Shari R; Kuczmarski, Marie Fanelli; Pohlig, Ryan T; Gerassimakis, Constance S; Gaynor, Beatrice; Evans, Michele K; Zonderman, Alan B

    2017-01-01

    Poor diet quality contributes to morbidity, including poor brain health outcomes such as cognitive decline and dementia. African Americans and individuals living in poverty may be at greater risk for cognitive decrements from poor diet quality. Cross-sectional. Baltimore, MD, USA. Participants were 2090 African Americans and Whites (57 % female, mean age=47·9 years) who completed two 24 h dietary recalls. We examined cognitive performance and potential interactions of diet quality with race and poverty status using baseline data from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. Healthy Eating Index-2010 (HEI-2010) scores were calculated and interpreted using federal guidelines. A neurocognitive test battery was administered to evaluate cognitive function over several domains. Linear regression analyses showed that lower HEI-2010 scores were associated with poorer verbal learning and memory (PDiet quality within the sample was poor. Significant interactions of HEI-2010 and poverty status (all Pdiet quality was associated with higher performance on tests of attention and cognitive flexibility, visuospatial ability and perceptual speed among those below the poverty line. No significant race interactions emerged. Higher diet quality was associated with better performance on two measures of verbal learning and memory, irrespective of race and poverty status. Findings suggest that diet quality and cognitive function are likely related at the population level. Future research is needed to determine whether the association is clinically significant.

  20. JNIH-ABCC life span study of children born to atomic bomb survivors. Report 1. Influence of concomitant variables upon mortality rate comparison

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Hiroo; Ueda, Shoichi

    1963-04-18

    The study of mortality rates among children born to atomic bomb survivors is being conducted according to the protocol, and at present, data for those whose parents are included in the Life Span Study sample are ready for analysis. Using this portion, the influence of various concomitant factors on the infant mortality rate was investigated. The distribution of year of birth, maternal age, and birth order differs between comparison groups. The differences introduce fairly large biases into mortality rate comparisons. For example, the infant mortality rate in children, both of whose parents were atomic bomb survivors would be overestimated by 10% or more. As far as such concomitant factors are observable, the bias can be reduced to negligible magnitude. Other factors are equally important but difficult to observe. For example, environmental factors influence mortality a great deal but adequate methods for treating such factors have not yet been found. If such bias is not eliminated, conclusions to be derived from this study suffer serious limitation, namely, unless drastic radiation effects exist, neither existence nor absence of radiation effects will be demonstrable. Investigation is continuing, especially concerning: how to measure environmental factors; regression analysis on radiation dose or distance from the hypocenter; and examination of specific causes of death. 7 references, 4 figures, 9 tables.

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

    Science.gov (United States)

    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.

  2. Infantile onset Vanishing White Matter disease associated with a novel EIF2B5 variant, remarkably long life span, severe epilepsy, and hypopituitarism.

    Science.gov (United States)

    Woody, April L; Hsieh, David T; McIver, Harkirtin K; Thomas, Linda P; Rohena, Luis

    2015-04-01

    Vanishing White Matter disease (VWM) is an inherited progressive leukoencephalopathy caused by mutations in the genes EIF2B1-5, which encode for the 5 subunits of the eukaryotic initiation factor 2B (eIF2B), a regulator of protein synthesis. VWM typically presents with acute neurological decline following febrile infections or minor head trauma, and subsequent progressive neurological and cognitive regression. There is a varied clinical spectrum of VWM, with earlier onset associated with more severe phenotypes. Brain magnetic resonance imaging is usually diagnostic with diffusely abnormal white matter, progressing over time to cystic degeneration. We are reporting on a patient with infantile onset VWM associated with three heterozygous missense variants in EIF2B5, including a novel missense variant on exon 6 of EIF2B5 (D262N), as well as an interstitial duplication at 7q21.12. In addition, our case is unusual because of a severe epilepsy course, a novel clinical finding of hypopituitarism manifested by hypothyroidism and adrenal insufficiency, and a prolonged life span with current age of survival of 4 years and 11 months. © 2015 Wiley Periodicals, Inc.

  3. 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

    Directory of Open Access Journals (Sweden)

    Wan-Chi eWong

    2014-05-01

    Full Text Available 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.

  4. Patterns of hippocampal-neocortical interactions in the retrieval of episodic autobiographical memories across the entire life-span of aged adults

    Science.gov (United States)

    Viard, Armelle; Lebreton, Karine; Chételat, Gaël; Desgranges, Béatrice; Landeau, Brigitte; Young, Alan; De La Sayette, Vincent; Eustache, Francis; Piolino, Pascale

    2010-01-01

    We previously demonstrated that Episodic Autobiographical Memories (EAMs) rely on a network of brain regions comprising the medial temporal lobe (MTL) and distributed neocortical regions regardless of their remoteness. The findings supported the model of memory consolidation which proposes a permanent role of MTL during EAM retrieval (Multiple-Trace Theory or MTT) rather than a temporary role (standard model). Our present aim was to expand the results by examining the interactions between the MTL and neocortical regions (or MTL-neocortical links) during EAM retrieval with varying retention intervals. We used an experimental paradigm specially designed to engage aged participants in the recollection of EAMs, extracted from five different time-periods, covering their whole life-span, in order to examine correlations between activation in the MTL and neocortical regions. The nature of the memories was checked at debriefing by means of behavioral measures to control the degree of episodicity and properties of memories. Targeted correlational analyses carried out on the MTL, frontal, lateral temporal and posterior regions revealed strong links between the MTL and neocortex during the retrieval of both recent and remote EAMs, challenging the standard model of memory consolidation and supporting MTT instead. Further confirmation was given by results showing that activation in the left and right hippocampi significantly correlated during the retrieval of both recent and remote memories. Correlations among extra-MTL neocortical regions also emerged for all time-periods, confirming the critical role of the prefrontal, temporal (lateral temporal cortex and temporal pole), precuneus and posterior cingulate regions in EAM retrieval. Overall, this paper emphasizes the role of a bilateral network of MTL and neocortical areas whose activation correlate during the recollection of rich phenomenological recent and remote EAMs. PMID:19338022

  5. Measurement invariance of big-five factors over the life span: ESEM tests of gender, age, plasticity, maturity, and la dolce vita effects.

    Science.gov (United States)

    Marsh, Herbert W; Nagengast, Benjamin; Morin, Alexandre J S

    2013-06-01

    This substantive-methodological synergy applies evolving approaches to factor analysis to substantively important developmental issues of how five-factor-approach (FFA) personality measures vary with gender, age, and their interaction. Confirmatory factor analyses (CFAs) conducted at the item level often do not support a priori FFA structures, due in part to the overly restrictive assumptions of CFA models. Here we demonstrate that exploratory structural equation modeling (ESEM), an integration of CFA and exploratory factor analysis, overcomes these problems with the 15-item Big Five Inventory administered as part of the nationally representative British Household Panel Study (N = 14,021; age: 15-99 years, Mage = 47.1). ESEM fitted the data substantially better and resulted in much more differentiated (less correlated) factors than did CFA. Methodologically, we extended ESEM (introducing ESEM-within-CFA models and a hybrid of multiple groups and multiple indicators multiple causes models), evaluating full measurement invariance and latent mean differences over age, gender, and their interaction. Substantively the results showed that women had higher latent scores for all Big Five factors except for Openness and that these gender differences were consistent over the entire life span. Substantial nonlinear age effects led to the rejection of the plaster hypothesis and the maturity principle but did support a newly proposed la dolce vita effect in old age. In later years, individuals become happier (more agreeable and less neurotic), more self-content and self-centered (less extroverted and open), more laid back and satisfied with what they have (less conscientious, open, outgoing and extroverted), and less preoccupied with productivity. PsycINFO Database Record (c) 2013 APA, all rights reserved

  6. Psychological Well-Being in Italian Families: An Exploratory Approach to the Study of Mental Health Across the Adult Life Span in the Blue Zone

    Science.gov (United States)

    Hitchcott, Paul Kenneth; Fastame, Maria Chiara; Ferrai, Jessica; Penna, Maria Pietronilla

    2017-01-01

    Self-reported measures of psychological well-being and depressive symptoms were examined across differently aged family members, while controlling for the impact of marital status and personal satisfaction about family and non-family relations. Twenty-one grandchildren (i.e., ages 21-36 years) were recruited with their parents (i.e., 48-66 years old) and grandparents (i.e., 75-101 years of age) in the ‘blue zone’ of Ogliastra, an Italian area known for the longevity of its inhabitants. Each participant was individually presented a battery of questionnaires assessing their lifestyle and several perceived mental health indices, including the Warwick-Edinburgh Mental Well-Being Scale (WEMWBS, Tennant et al., 2007), and the Center for Epidemiologic Studies Depression Scale (i.e., CES-D, Radloff, 1977). After assessing the level of concordance among adults sharing the same context, the Hierarchical Linear Modeling (HLM) approach was used to assess the nested dataset. It was found that family membership (i.e., grandchildren versus parents and grandparents) predicted the WEMWBS score but not the CES-D when the impact of marital status and personal satisfaction about social (i.e., family and non-family) ties was controlled for. Moreover, two separate repeated-measure Analyses of Variance (ANOVAs) documented similar level of personal satisfaction about social relationships across the three family groups. In conclusions, satisfying social ties with friends and family members together with an active socially oriented life style seems to contribute to the promotion of mental health in adult span. PMID:28904594

  7. Stimulation of anti-tumor effect by low-dose irradiation. Pt. 2. The prolongation of life span in AKR mice

    International Nuclear Information System (INIS)

    Ishii, Keiichiro; Misonoh, Jun; Hosoi, Yoshio; Ono, Tetsuya; Sakamoto, Kiyohiko.

    1994-01-01

    To elucidate the antileukemic effect of low-dose X-irradiation, we studied the influence of periodical low-dose X-irradiation on survival and tumor incidence of thymus using AKR mice. The findings of the experiments were as follows; (1) The median survival time of control AKR mice was 283±3 days. It of irradiation group of 15 cGy/week and 30cGy was 309±14 days and 316±10 days respectively. The life span was significantly prolonged (p < 0.05 and p < 0.01 respectively by Wilcoxon test) by periodical low-dose X-irradiation in term of breeding. (2) The incidence of thymus tumor which is observed remarkably in control AKR mice was 48.8%. It of irradiation group of 15 cGy/week and 30 cGy/week was 40% and 20% respectively. Inversely, the non-tumor incidence of tymus in control AKR mice was 19.5%. It of irradiation group of 15 cGy/week and 30 cGy/week was 32.5% and 51.4% respectively. The thymic tumor incidence was significantly decreased (p < 0.01 by chi-square test) in irradiation group of 30 cGy/week. (3) The incidence of thymic lymphoma as a death cause in control AKR mice was 80.4%. It of irradiation group of 15 cGy/week and 30cGy/week was 67.5% and 48.6% respectively. The incidence of thymic lymphoma was significantly decreased (p < 0.05 by chi-square test) in irradiation group of 30 cGy/week. (author)

  8. Genetic Dissection of Nutrition-Induced Plasticity in Insulin/Insulin-Like Growth Factor Signaling and Median Life Span in a Drosophila Multiparent Population.

    Science.gov (United States)

    Stanley, Patrick D; Ng'oma, Enoch; O'Day, Siri; King, Elizabeth G

    2017-06-01

    The nutritional environments that organisms experience are inherently variable, requiring tight coordination of how resources are allocated to different functions relative to the total amount of resources available. A growing body of evidence supports the hypothesis that key endocrine pathways play a fundamental role in this coordination. In particular, the insulin/insulin-like growth factor signaling (IIS) and target of rapamycin (TOR) pathways have been implicated in nutrition-dependent changes in metabolism and nutrient allocation. However, little is known about the genetic basis of standing variation in IIS/TOR or how diet-dependent changes in expression in this pathway influence phenotypes related to resource allocation. To characterize natural genetic variation in the IIS/TOR pathway, we used >250 recombinant inbred lines (RILs) derived from a multiparental mapping population, the Drosophila Synthetic Population Resource, to map transcript-level QTL of genes encoding 52 core IIS/TOR components in three different nutritional environments [dietary restriction (DR), control (C), and high sugar (HS)]. Nearly all genes, 87%, were significantly differentially expressed between diets, though not always in ways predicted by loss-of-function mutants. We identified cis ( i.e. , local) expression QTL (eQTL) for six genes, all of which are significant in multiple nutrient environments. Further, we identified trans ( i.e. , distant) eQTL for two genes, specific to a single nutrient environment. Our results are consistent with many small changes in the IIS/TOR pathways. A discriminant function analysis for the C and DR treatments identified a pattern of gene expression associated with the diet treatment. Mapping the composite discriminant function scores revealed a significant global eQTL within the DR diet. A correlation between the discriminant function scores and the median life span ( r = 0.46) provides evidence that gene expression changes in response to diet are

  9. Span of control matters.

    Science.gov (United States)

    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.

  10. Chronological age and its impact on associative learning proficiency and brain structure in middle adulthood.

    Science.gov (United States)

    Diwadkar, Vaibhav A; Bellani, Marcella; Ahmed, Rizwan; Dusi, Nicola; Rambaldelli, Gianluca; Perlini, Cinzia; Marinelli, Veronica; Ramaseshan, Karthik; Ruggeri, Mirella; Bambilla, Paolo

    2016-01-15

    The rate of biological change in middle-adulthood is relatively under-studied. Here, we used behavioral testing in conjunction with structural magnetic resonance imaging to examine the effects of chronological age on associative learning proficiency and on brain regions that previous functional MRI studies have closely related to the domain of associative learning. Participants (n=66) completed a previously established associative learning paradigm, and consented to be scanned using structural magnetic resonance imaging. Age-related effects were investigated both across sub-groups in the sample (younger vs. older) and across the entire sample (using regression approaches). Chronological age had substantial effects on learning proficiency (independent of IQ and Education Level), with older adults showing a decrement compared to younger adults. In addition, decreases in estimated gray matter volume were observed in multiple brain regions including the hippocampus and the dorsal prefrontal cortex, both of which are strongly implicated in associative learning. The results suggest that middle adulthood may be a more dynamic period of life-span change than previously believed. The conjunctive application of narrowly focused tasks, with conjointly acquired structural MRI data may allow us to enrich the search for, and the interpretation of, age-related changes in cross-sectional samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Autophagy and leucine promote chronological longevity and respiration proficiency during calorie restriction in yeast.

    Science.gov (United States)

    Aris, John P; Alvers, Ashley L; Ferraiuolo, Roy A; Fishwick, Laura K; Hanvivatpong, Amanda; Hu, Doreen; Kirlew, Christine; Leonard, Michael T; Losin, Kyle J; Marraffini, Michelle; Seo, Arnold Y; Swanberg, Veronica; Westcott, Jennifer L; Wood, Michael S; Leeuwenburgh, Christiaan; Dunn, William A

    2013-10-01

    We have previously shown that autophagy is required for chronological longevity in the budding yeast Saccharomyces cerevisiae. Here we examine the requirements for autophagy during extension of chronological life span (CLS) by calorie restriction (CR). We find that autophagy is upregulated by two CR interventions that extend CLS: water wash CR and low glucose CR. Autophagy is required for full extension of CLS during water wash CR under all growth conditions tested. In contrast, autophagy was not uniformly required for full extension of CLS during low glucose CR, depending on the atg allele and strain genetic background. Leucine status influenced CLS during CR. Eliminating the leucine requirement in yeast strains or adding supplemental leucine to growth media extended CLS during CR. In addition, we observed that both water wash and low glucose CR promote mitochondrial respiration proficiency during aging of autophagy-deficient yeast. In general, the extension of CLS by water wash or low glucose CR was inversely related to respiration deficiency in autophagy-deficient cells. Also, autophagy is required for full extension of CLS under non-CR conditions in buffered media, suggesting that extension of CLS during CR is not solely due to reduced medium acidity. Thus, our findings show that autophagy is: (1) induced by CR, (2) required for full extension of CLS by CR in most cases (depending on atg allele, strain, and leucine availability) and, (3) promotes mitochondrial respiration proficiency during aging under CR conditions. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Relative chronology of Martian volcanoes

    International Nuclear Information System (INIS)

    Landheim, R.; Barlow, N.G.

    1991-01-01

    Impact cratering is one of the major geological processes that has affected the Martian surface throughout the planet's history. The frequency of craters within particular size ranges provides information about the formation ages and obliterative episodes of Martian geologic units. The Barlow chronology was extended by measuring small craters on the volcanoes and a number of standard terrain units. Inclusions of smaller craters in units previously analyzed by Barlow allowed for a more direct comparison between the size-frequency distribution data for volcanoes and established chronology. During this study, 11,486 craters were mapped and identified in the 1.5 to 8 km diameter range in selected regions of Mars. The results are summarized in this three page report and give a more precise estimate of the relative chronology of the Martian volcanoes. Also, the results of this study lend further support to the increasing evidence that volcanism has been a dominant geologic force throughout Martian history

  13. A dwarf mouse model with decreased GH/IGF-1 activity that does not experience life-span extension: potential impact of increased adiposity, leptin, and insulin with advancing age.

    Science.gov (United States)

    Berryman, Darlene E; Lubbers, Ellen R; Magon, Vishakha; List, Edward O; Kopchick, John J

    2014-02-01

    Reduced growth hormone (GH) action is associated with extended longevity in many vertebrate species. GH receptor (GHR) null (GHR(-)(/-)) mice, which have a disruption in the GHR gene, are a well-studied example of mice that are insulin sensitive and long lived yet obese. However, unlike other mouse lines with reduced GH action, GH receptor antagonist (GHA) transgenic mice have reduced GH action yet exhibit a normal, not extended, life span. Understanding why GHA mice do not have extended life span though they share many physiological attributes with GHR(-)(/-) mice will help provide clues about how GH influences aging. For this study, we examined age- and sex-related changes in body composition, glucose homeostasis, circulating adipokines, and tissue weights in GHA mice and littermate controls. Compared with previous studies with GHR(-)(/-) mice, GHA mice had more significant increases in fat mass with advancing age. The increased obesity resulted in significant adipokine changes. Euglycemia was maintained in GHA mice; however, hyperinsulinemia developed in older male GHA mice. Overall, GHA mice experience a more substantial, generalized obesity accompanied by altered adipokine levels and glucose homeostasis than GHR(-)(/-) mice, which becomes more exaggerated with advancing age and which likely contributes to the lack of life-span extension in these mice.

  14. Astronautics and aeronautics, 1977: A chronology

    Science.gov (United States)

    Ritchie, E. H.

    1986-01-01

    This publication is a chronology of events during the year 1977 in the fields of aeronautical and space research, development, activity, and policy. It includes appendixes, an index, and illustrations. Chronological entries list sources for further inquiry.

  15. Comparing records with related chronologies

    Science.gov (United States)

    Bronk Ramsey, Christopher; Albert, Paul; Kearney, Rebecca; Staff, Richard A.

    2016-04-01

    In order to integrate ice, terrestrial and marine records, it is necessary to deal with records on different timescales. These timescales can be grouped into those that use a common fundamental chronometer (such as Uranium-Thorium dating or Radiocarbon) and can also be related to one another where we have chronological tie points such as tephra horizons. More generally we can, through a number of different methodologies, derive relationships between different timescales. A good example of this is the use of cosmogenic isotope production, specifically 10Be and 14C to relate the calibrated radiocarbon timescale to that of the Greenland ice cores. The relationships between different timescales can be mathematically expressed in terms of time-transfer functions. This formalism allows any related record to be considered against any linked timescale with an appropriate associated uncertainty. The prototype INTIMATE chronological database allows records to be viewed and compared in this way and this is now being further developed, both to include a wider range of records and also to provide better connectivity to other databases and chronological tools. These developments will also include new ways to use tephra tie-points to constrain the relationship between timescales directly, without needing to remodel each associated timescale. The database as it stands allows data for particular timeframes to be recalled and plotted against any timescale, or exported in spreadsheet format. New functionality will be added to allow users to work with their own data in a private space and then to publish it when it has been through the peer-review publication process. In order to make the data easier to use for other further analysis and plotting, and with data from other sources, the database will also act as a server to deliver data in a JSON format. The aim of this work is to make the comparison of integrated data much easier for researchers and to ensure that good practice in

  16. Phytoseiid mites in protected crops: the effect of humidity and food availability on egg hatch and adult life span of Iphiseius degenerans, Neoseiulus cucumeris, N. californicus and Phytoseiulus persimilis (Acari: Phytoseiidae).

    Science.gov (United States)

    De Courcy Williams, Michael E; Kravar-Garde, Lidija; Fenlon, John S; Sunderland, Keith D

    2004-01-01

    The effect of relative humidity on egg hatch success for Iphiseius degenerans, Neoseiulus californicus and N. cucumeris was described by a binomial model with a parallel slope. The shape of the response differed for Phytoseiulus persimilis and a model with separate parameters gave a significantly better fit. Fitted response curves showed that I. degenerans, N. cucumeris, N. californicus and P. persimilis were ranked by decreasing tolerance to low humidity, with egg mortalities of persimilis egg duration was significantly longer at 60 and 70% than for either 82 or 90% RH. No effect of relative humidity was found on the mean life span of adult females when food was available continuously to the mites. N. californicus lived significantly longer (58 days after the first egg was laid) than the other species. No significant difference was observed in mean life span between adult females of I. degenerans and N. cucumeris (25 and 28 days respectively). The mean life span of adult female P. persimilis (19 days) was significantly shorter than the other species. In the absence of both food and water, the survival of adult female mites was reduced to 2-4 days. Survival time was at least doubled when free water was available in the absence of food. Mean survival of adult female mites with water but without food was 10 days for N. cucumeris, 18 days for N. californicus, 6 days for P. persimilis and 4 days for I. degenerans. Survival of adult female N. cucumeris and N. californicus was increased significantly, to 20 and 22 days respectively, when fungal hyphae were present along with water but in the absence of other food.

  17. Complexity, Sustainability, Justice, and Meaning: Chronological Versus Dynamical Time

    Directory of Open Access Journals (Sweden)

    Horacio Velasco

    2009-11-01

    Full Text Available

    <span style="font-size: small;"><span style="font-family: Times New Roman;">Abstract: It is shown that time may be appreciated in at least two senses: chronological and dynamical. Chronological time is the time of our naïve acquaintance as transient beings. At its most extensive scale, it corresponds to history encompassing both the abiotic and the biotic<span style="mso-spacerun: yes;">  universe. Dynamical time, deriving from classical mechanics, is the time embraced by most of the laws of physics. It concerns itself only with present conditions since it is held that that the past may be reconstructed from the present (literally and the future predicted from the present, a position known as Laplacian determinism.

    <span style="font-size: small; font-family: Times New Roman;"> 

    <span style="font-size: small;"><span style="font-family: Times New Roman;">Nonlinear dynamics has shown the fallacy of this supposition because, of necessity, the concrete values that may be assumed in the variables of the equations of motion constituting the laws of physics (i.e. the present or starting conditions as a result of the spontaneous or intentional interaction of subject (or measuring systems and of object (or measured systems, cannot be of infinite precision. Indeed, even if they could be, it is not at all clear that they would permit Laplacian determinism because of what is thought to be the ubiquity of K-flow dynamics in nature in which even infinite past information leading to the present cannot yield prediction of the future. In consequence, nonlinear dynamics, in rebellion against dynamical time, generates a primitive form of history distinguishing past, present, and future that may be termed nonlinear dynamical hysteresis.

    <span style

  18. 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?

    Science.gov (United States)

    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.

  19. The influence of the hot water extract from shiitake medicinal mushroom, Lentinus edodes (higher Basidiomycetes) on the food intake, life span, and age-related locomotor activity of Drosophila melanogaster.

    Science.gov (United States)

    Matjuskova, Natalya; Azena, Elena; Serstnova, Ksenija; Muiznieks, Indrikis

    2014-01-01

    Shiitake medicinal mushroom, Lentinus edodes, is among the most widely cultivated edible mushrooms in the world and is a well-studied source of nutrients and biologically active compounds. We have studied the influence of the dietary supplement of the polysaccharides containing a hot water extract of the mushroom L. edodes on the fruit fly Drosophila melanogaster in terms of food intake, body weight, life span, and age-related locomotor activity. L. edodes extract, when added to the D. melanogaster feeding substrate at a 0.003-0.030% concentration (calculated for the dry weight of the polysaccharide fraction) did not influence food intake or body weight of the flies. It increased the life span and locomotor activities of male flies but was associated with early mortality and decreased locomotor activity of female flies. We conclude that the observed anti-aging effects of L. edodes extracts in the male D. melanogaster are not the result of dietary restriction. We propose that D. melanogaster is a suitable model organism for researching the molecular basis of the anti-aging effect of the shiitake mushroom extracts and sex linkage of these effects.

  20. Communicating Employability Enhancement throughout the Life-Span: A National Intervention Program Aimed at Combating Age-Related Stereotypes at the Workplace

    Science.gov (United States)

    van Selm, Martine; Van der Heijden, Beatrice I. J. M.

    2013-01-01

    The stimulation of lifelong employability of employees is one of today's challenges in all sectors of the Dutch society. In this article, we will outline the historical context of the life-long employability issue in the Netherlands, and provide an overview of current business responses to the issue. We will discuss key obstacles for improving…

  1. Communicating employability enchancement throughout the life-span: a national intervention program aimed at combating age-related stereotypes at the workplace

    NARCIS (Netherlands)

    van Selm, M.; van der Heijden, B.I.J.M.

    2013-01-01

    The stimulation of lifelong employability of employees is one of today's challenges in all sectors of the Dutch society. In this article, we will outline the historical context of the life-long employability issue in the Netherlands, and provide an overview of current business responses to the

  2. Communicating Employability Enhancement Throughout the Life-Span: A National Intervention Program Aimed at Combating Age-Related Stereotypes at the Workplace

    NARCIS (Netherlands)

    van Selm, Martine; van der Heijden, Beatrice

    2013-01-01

    The stimulation of lifelong employability of employees is one of today's challenges in all sectors of the Dutch society. In this article, we will outline the historical context of the life-long employability issue in the Netherlands, and provide an overview of current business responses to the

  3. Appendix 2: Chronology of events

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    The accident at the Chernobyl nuclear power plant and its consequences are set in chronological order from April 1986 to March 1988. The loss of confidence in nuclear power is clearly shown in the list of withdrawal or cancellations of reactor orders, especially those soon after the accident. Levels of radioactivity in food monitored in the UK and Europe is also listed. The International Atomic Energy Agency's Conventions on early notification and assistance and similar agreements to improve nuclear safety are included. The list is selective and includes both positive and negative consequences of the accident. (U.K.)

  4. Deep sea minerals prolong life span of streptozotocin-induced diabetic rats by compensatory augmentation of the IGF-I-survival signaling and inhibition of apoptosis.

    Science.gov (United States)

    Liao, Hung-En; Shibu, Marthandam Asokan; Kuo, Wei-Wen; Pai, Pei-Ying; Ho, Tsung-Jung; Kuo, Chia-Hua; Lin, Jing-Ying; Wen, Su-Ying; Viswanadha, Vijaya Padma; Huang, Chih-Yang

    2016-07-01

    Consumption of deep sea minerals (DSM), such as magnesium, calcium, and potassium, is known to reduce hypercholesterolemia-induced myocardial hypertrophy and cardiac-apoptosis and provide protection against cardiovascular diseases. Heart diseases develop as a lethal complication among diabetic patients usually due to hyperglycemia-induced cardiac-apoptosis that causes severe cardiac-damages, heart failure, and reduced life expectancy. In this study, we investigated the potential of DSM and its related cardio-protection to increase the life expectancy in diabetic rats. In this study, a heart failure rat model was developed by using streptozotocin (65 mg kg(-1) ) IP injection. Different doses of DSM-1× (37 mg kg(-1) day(-1) ), 2× (74 mg kg(-1) day(-1) ) and 3× (111 mg kg(-1) day(-1) ), were administered to the rats through gavages for 4 weeks. The positive effects of DSM on the survival rate of diabetes rats were determined with respect to the corresponding effects of MgSO4 . Further, to understand the mechanism by which DSM enhances the survival of diabetic rats, their potential to regulate cardiac-apoptosis and control cardiac-dysfunction were examined. Echocardiogram, tissue staining, TUNEL assay, and Western blotting assay were used to investigate modulations in the myocardial contractile function and related signaling protein expression. The results showed that DSM regulate apoptosis and complement the cardiomyocyte proliferation by enhancing survival mechanisms. Moreover DSM significantly reduced the mortality rate and enhanced the survival rate of diabetic rats. Experimental results show that DSM administration can be an effective strategy to improve the life expectancy of diabetic subjects by improving cardiac-cell proliferation and by controlling cardiac-apoptosis and associated cardiac-dysfunction. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 769-781, 2016. © 2015 Wiley Periodicals, Inc.

  5. Span efficiency in hawkmoths.

    Science.gov (United States)

    Henningsson, Per; Bomphrey, Richard J

    2013-07-06

    Flight in animals is the result of aerodynamic forces generated as flight muscles drive the wings through air. Aerial performance is therefore limited by the efficiency with which momentum is imparted to the air, a property that can be measured using modern techniques. We measured the induced flow fields around six hawkmoth species flying tethered in a wind tunnel to assess span efficiency, ei, and from these measurements, determined the morphological and kinematic characters that predict efficient flight. The species were selected to represent a range in wingspan from 40 to 110 mm (2.75 times) and in mass from 0.2 to 1.5 g (7.5 times) but they were similar in their overall shape and their ecology. From high spatio-temporal resolution quantitative wake images, we extracted time-resolved downwash distributions behind the hawkmoths, calculating instantaneous values of ei throughout the wingbeat cycle as well as multi-wingbeat averages. Span efficiency correlated positively with normalized lift and negatively with advance ratio. Average span efficiencies for the moths ranged from 0.31 to 0.60 showing that the standard generic value of 0.83 used in previous studies of animal flight is not a suitable approximation of aerodynamic performance in insects.

  6. Time in tortoiseshell: a bomb radiocarbon-validated chronology in sea turtle scutes.

    Science.gov (United States)

    Van Houtan, Kyle S; Andrews, Allen H; Jones, T Todd; Murakawa, Shawn K K; Hagemann, Molly E

    2016-01-13

    Some of the most basic questions of sea turtle life history are also the most elusive. Many uncertainties surround lifespan, growth rates, maturity and spatial structure, yet these are critical factors in assessing population status. Here we examine the keratinized hard tissues of the hawksbill (Eretmochelys imbricata) carapace and use bomb radiocarbon dating to estimate growth and maturity. Scutes have an established dietary record, yet the large keratin deposits of hawksbills evoke a reliable chronology. We sectioned, polished and imaged posterior marginal scutes from 36 individual hawksbills representing all life stages, several Pacific populations and spanning eight decades. We counted the apparent growth lines, microsampled along growth contours and calibrated Δ(14)C values to reference coral series. We fit von Bertalanffy growth function (VBGF) models to the results, producing a range of age estimates for each turtle. We find Hawaii hawksbills deposit eight growth lines annually (range 5-14), with model ensembles producing a somatic growth parameter (k) of 0.13 (range 0.1-0.2) and first breeding at 29 years (range 23-36). Recent bomb radiocarbon values also suggest declining trophic status. Together, our results may reflect long-term changes in the benthic community structure of Hawaii reefs, and possibly shed light on the critical population status for Hawaii hawksbills. © 2016 The Author(s).

  7. 'The brain is the organ of longevity': Introduction to G. A. Sacher's free-energy hypothesis of life-span enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Justesen, D.R.

    1981-10-01

    No experiment reported to date constitutes an adequate test in the sense of supplying comprehensive information on survival time, metabolic rate, food consumption and utilization, body mass, anatomical integrity (especially that of the skeletal and nervous systems), status of the immune and endocrine systems, and physiological and behavioral competence in the wake of chronic exposure to a moderately thermalizing radio field. Some reports do provide data on one or more of the important end points, usually in association with a single exposure or a limited number of brief exposures. One must distinguish between prolongation of life in senescence and enhancement of longevity based on actual retardation of the rate of aging. More, retardation of aging, if sorely taxed at the expense of quality of living, is no bargain. Some hibernators live relatively long lives, but the torpor of hibernation--a prolonged period of somnolence and greatly reduced metabolic activity--is hardly the stuff of a vibrant psychological existence.

  8. Health-related quality of life in a multicenter randomized controlled comparison of telephonic disease management and automated home monitoring in patients recently hospitalized with heart failure: SPAN-CHF II trial.

    Science.gov (United States)

    Konstam, Varda; Gregory, Douglas; Chen, Jie; Weintraub, Andrew; Patel, Ayan; Levine, Daniel; Venesy, David; Perry, Kathleen; Delano, Christine; Konstam, Marvin A

    2011-02-01

    Although disease management programs have been shown to provide a number of clinical benefits to patients with heart failure (HF), the incremental impact of an automated home monitoring (AHM) system on health-related quality of life (HRQL) is unknown. We performed a prospective randomized investigation, examining the additive value of AHM to a previously described nurse-directed HF disease management program (SPAN-CHF), with attention to HRQL, in patients with a recent history of decompensated HF. A total of 188 patients were randomized to receive the SPAN-CHF intervention for 90 days, either with (AHM group) or without (NAHM, standard-care group) AHM, with a 1:1 randomization ratio after HF-related hospitalization. HRQL, measured by the Minnesota Living With Heart Failure Questionnaire (MLHFQ) (Physical, Emotional, and Total scores on MLHFQ) was assessed at 3 time points: baseline, 45 days, and 90 days. Although both treatments (AHM and NAHM) improved HRQL at 45 and 90 days compared with baseline with respect to Physical, Emotional, and Total domain scales, no significant difference emerged between AHM and NAHM groups. AHM and NAHM treatments demonstrated improved HRQL scores at 45 and 90 days after baseline assessment. When comparing 2 state-of the-art disease management programs regarding HRQL outcomes, our results did not support the added value of AHM. Copyright © 2011. Published by Elsevier Inc.

  9. Reassessment of the Upper Fremont Glacier ice-core chronologies by synchronizing of ice-core-water isotopes to a nearby tree-ring chronology

    Science.gov (United States)

    Chellman, Nathan J.; McConnell, Joseph R.; Arienzo, Monica; Pederson, Gregory T.; Aarons, Sarah; Csank, Adam

    2017-01-01

    The Upper Fremont Glacier (UFG), Wyoming, is one of the few continental glaciers in the contiguous United States known to preserve environmental and climate records spanning recent centuries. A pair of ice cores taken from UFG have been studied extensively to document changes in climate and industrial pollution (most notably, mid-19th century increases in mercury pollution). Fundamental to these studies is the chronology used to map ice-core depth to age. Here, we present a revised chronology for the UFG ice cores based on new measurements and using a novel dating approach of synchronizing continuous water isotope measurements to a nearby tree-ring chronology. While consistent with the few unambiguous age controls underpinning the previous UFG chronologies, the new interpretation suggests a very different time scale for the UFG cores with changes of up to 80 years. Mercury increases previously associated with the mid-19th century Gold Rush now coincide with early-20th century industrial emissions, aligning the UFG record with other North American mercury records from ice and lake sediment cores. Additionally, new UFG records of industrial pollutants parallel changes documented in ice cores from southern Greenland, further validating the new UFG chronologies while documenting the extent of late 19th and early 20th century pollution in remote North America.

  10. Chronology of early lunar crust

    International Nuclear Information System (INIS)

    Dasch, E.J.; Nyquist, L.E.; Ryder, G.

    1988-01-01

    The chronology of lunar rocks is summarized. The oldest pristine (i.e., lacking meteoritic contamination of admixed components) lunar rock, recently dated with Sm-Nd by Lugmair, is a ferroan anorthosite, with an age of 4.44 + 0.02 Ga. Ages of Mg-suite rocks (4.1 to 4.5 Ga) have large uncertainties, so that age differences between lunar plutonic rock suites cannot yet be resolved. Most mare basalts crystallized between 3.1 and 3.9 Ga. The vast bulk of the lunar crust, therefore, formed before the oldest preserved terrestrial rocks. If the Moon accreted at 4.56 Ga, then 120 Ma may have elapsed before lunar crust was formed

  11. Chronology protection in string theory

    International Nuclear Information System (INIS)

    Dyson, Lisa

    2004-01-01

    Many solutions of General Relativity appear to allow the possibility of time travel. This was initially a fascinating discovery, but geometries of this type violate causality, a basic physical law which is believed to be fundamental. Although string theory is a proposed fundamental theory of quantum gravity, geometries with closed timelike curves have resurfaced as solutions to its low energy equations of motion. In this paper, we will study the class of solutions to low energy effective supergravity theories related to the BMPV black hole and the rotating wave-D1-D5-brane system. Time travel appears to be possible in these geometries. We will attempt to build the causality violating regions and propose that stringy effects prohibit their construction. The proposed chronology protection agent for these geometries mirrors a mechanism string theory employs to resolve a class of naked singularities. (author)

  12. Dual boundary spanning

    DEFF Research Database (Denmark)

    Li-Ying, Jason

    2016-01-01

    The extant literature runs short in understanding openness of innovation regarding and the different pathways along which internal and external knowledge resources can be combined. This study proposes a unique typology for outside-in innovations based on two distinct ways of boundary spanning......: whether an innovation idea is created internally or externally and whether an innovation process relies on external knowledge resources. This yields four possible types of innovation, which represent the nuanced variation of outside-in innovations. Using historical data from Canada for 1945...

  13. Leaf life spans of some conifers of the temperate forests of South America Longevidad foliar de algunas coníferas de los bosques templados de Sudamérica

    Directory of Open Access Journals (Sweden)

    CHRISTOPHER H. LUSK

    2001-09-01

    Full Text Available Interspecific variation in leaf life span has wide-ranging implications for plant species sorting on resource availability gradients, and for ecosystem processes such as nutrient cycling. Very little is known about leaf life spans of evergreen trees in the temperate forests of South America. Leaf life spans were estimated by static demographic methods, and associated leaf traits measured, for four conifers of this region. It was expected that leaf life span variation would correlate negatively with soil fertility of habitats normally occupied by each species. This prediction was upheld by the data. The mean leaf life span determined for Araucaria araucana (24 years is among the highest figures reported for any plant species. This extreme leaf longevity was associated with very robust construction (high leaf mass per unit area and very low nitrogen content. These aspects of the ecology of A. araucana may affect its fitness in two ways. Firstly, slow foliage turnover will reduce its annual nutrient requirements for crown maintenance, a trait that is thought to be crucial for survival on nutrient-poor sites. Secondly, the low decomposability of A. araucana leaf litter is likely to cause nutrient immobilisation, possibly favouring site retention by A. araucana in the face of competition from faster-growing but more nutrient-demanding species. Interspecific variation in leaf life span appeared to be systematically related to variation in leaf mass per unit area (LMA and leaf nitrogen, in agreement with a large body of evidence that leaf evolution is constrained by a trade-off between trait combinations which optimise carbon gain and growth in resource-rich habitats, and those which favour persistence in chronically adverse environmentsLas diferencias específicas en longevidad foliar tienen importantes implicancias para la distribución de las plantas en relación con gradientes de recursos, y en procesos ecosistémicos tales como el ciclaje de

  14. Life-span effects of ionizing radiation in the beagle dog: A summary account of four decades of research funded by the US Department of Energy and its predecessor agencies

    International Nuclear Information System (INIS)

    Thompson, R.C.

    1989-01-01

    Nearly 40 years ago, the US Atomic Energy Commission made a far- reaching commitment to the support of life-span radiation-effects studies in a relatively long-lived animal, the beagle dog. Something in the range of 200 million dollars has already been spent on a group of closely related experiments, many of which are only now coming to fruition. Responsible fiscal management of these studies, directed toward securing an optimum return from past investments, and toward creative planning of future directions, requires a comprehensive view of this total effort. This report is designed to provide that comprehensive view. This is primarily intended as a research management document. Evaluation and interpretation are tasks for those directly involved in conducting these experiments. The limited objective of the present document is to describe what has been done, to give some of the background for why it was done, to describe results already realized and applications that have been made of these results -- all in a manner designed to display the total effort rather than piecemeal details. While proposing no specific answers to the questions ''Where do we go from here?''it is hoped that the document will provide a basis for approaching that question in an informed manner. The maintenance of a continuity of scientific understanding and direction in these experiments, which often continue beyond the initiating investigators' working life, is no small part of the problem involved in conducting these experiments

  15. Life-span effects of ionizing radiation in the beagle dog: A summary account of four decades of research funded by the US Department of Energy and its predecessor agencies

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, R.C.

    1989-01-01

    Nearly 40 years ago, the US Atomic Energy Commission made a far- reaching commitment to the support of life-span radiation-effects studies in a relatively long-lived animal, the beagle dog. Something in the range of 200 million dollars has already been spent on a group of closely related experiments, many of which are only now coming to fruition. Responsible fiscal management of these studies, directed toward securing an optimum return from past investments, and toward creative planning of future directions, requires a comprehensive view of this total effort. This report is designed to provide that comprehensive view. This is primarily intended as a research management document. Evaluation and interpretation are tasks for those directly involved in conducting these experiments. The limited objective of the present document is to describe what has been done, to give some of the background for why it was done, to describe results already realized and applications that have been made of these results -- all in a manner designed to display the total effort rather than piecemeal details. While proposing no specific answers to the questions ''Where do we go from here.''it is hoped that the document will provide a basis for approaching that question in an informed manner. The maintenance of a continuity of scientific understanding and direction in these experiments, which often continue beyond the initiating investigators' working life, is no small part of the problem involved in conducting these experiments.

  16. Age and the Tenses of Life Satisfaction

    Science.gov (United States)

    2013-01-01

    Objective. People have a special capacity to live simultaneously in both chronological and biographical time. In this article, we examine reports of life satisfaction that span past, present, and future, considering how perceived changes in certain life domains are associated with overall perceived life trajectories. Methods. Analyses use men and women from the Midlife Development in the United States survey. We employ gender-stratified fixed effects regression models to examine the net effect of satisfaction with finances, partnerships/marriage, sex, contribution to others, work, health, and relationship with children on trajectories of overall life satisfaction. Results. Among men, partnership and financial satisfaction had the strongest association with life satisfaction. Women displayed a somewhat broader range of domains related to their trajectories of life satisfaction. Partnership was most important, but their sense of evolving life satisfaction was also tied to their relationship with their children, sexuality, work situation, contribution to others’ welfare, and financial situation. Discussion. We find several notable differences between men and women, but the most telling differences emerge among women themselves across chronological time. For women, partner satisfaction becomes considerably more important across the age groups, whereas sex, contribution to others, and relationships with children all decrease in their importance for overall life satisfaction. PMID:23704205

  17. The life span of the biosphere revisited

    Science.gov (United States)

    Caldeira, Ken; Kasting, James F.

    1992-01-01

    How much longer the biosphere can survive on earth is reexamined using a more elaborate model than that of Lovelock and Whitfield (1982). The model includes a more accurate treatment of the greenhouse effect of CO2, a biologically mediated weathering parametrization, and the realization that C4 photosynthesis can persist to much lower concentrations of atmospheric CO2. It is found that a C4-plant-based biosphere could survive for at least another 0.9 Gyr to 1.5 Gyr after the present time, depending respectively on whether CO2 or temperature is the limiting factor. Within an additional 1 Gyr, earth may lose water to space, thereby following the path of Venus.

  18. Life-span of leadwood trees

    CSIR Research Space (South Africa)

    Vogel, JC

    2005-01-01

    Full Text Available with radiocarbon from the atom bomb tests. S. Afr. J. Sci. 98, 437?438. Table 2. Summary of the dating results. Specimen Description Diameter Age Radial growth rate Survival since death (m) (yr) (mm yr?1) (yr) LW 1 Upright dead tree 0.68 1040 0.33 22 LW 2 Standing... bythecombustionoffossilfuelsthatdonotcontaintheradioactive isotope. After AD 1954, the testing of nuclear fusion bombs dramaticallyincreasedthe14Ccontentintheatmosphere,sothat material dating to after this date shows an elevated 14C level and can be pinpointed precisely to ?1 year.4 Materials and method...

  19. Life Span Personality Stability in Sibling Statuses.

    Science.gov (United States)

    Rosenberg, B. G.

    Personality stability and change in sibling status in the one- and two-child-family are examined in this Study. Q-sort data were analyzed for the same 33 male and 34 female subjects during four periods of their lives-- early and late adolescence and early and middle adulthood. Results indicate that stability of personality was greatest during…

  20. Life span study report 11, part 1

    International Nuclear Information System (INIS)

    Shimizu, Yukiko; Kato, Hiroo; Schull, W.J.; Preston, D.L.; Fujita, Shoichiro; Pierce, D.A.

    1987-11-01

    In 75,991 A-bomb survivors, shielded kerma and organ doses were calculated based on the new dosimetry system 1986 (DS86) and the previous tentative 1965 dose revised (T65DR) to compare risk coefficients for site-specific cancer mortality during the period 1950 - 1985. As for shielded kerma, the excess relative risk over the various sites and the excess numbers of cancer deaths per 10 4 person-year-gray were 1.35 - 1.51 and 1.38 - 1.61 times higher, respectively, under the DS86 than under the T65DR. The attributable risks did not differ in the two dosimetric systems. The risk coefficients based on the DS86 organ-absorbed doses were generally smaller than those based on the T65DR values. The difference in cancer mortality between Hiroshima and Nagasaki was smaller with the DS86 than with the T65DR; however, this was not statistically significant for either shielded kerma and organ-absorbed dose. (Namekawa, K.)

  1. Life span study report 10 - 1

    International Nuclear Information System (INIS)

    Preston, D.L.; Kato, Hiroo; Kopecky, K.J.; Fujita, Shoichiro.

    1987-08-01

    The present study extends the previous report on cancer mortality among atomic bomb survivors by adding data from four additional years of follow-up (1979 - 82) and by expanding the cohort (now designated LSS-E85) to include 11,393 Nagasaki survivors located between 2,500 - 9,999 m from the hypocenter at the time of the bombing (ATB). Significant dose responses were observed for leukemia, for cancers of the lung, female breast, stomach, colon, esophagus, and urinary bladder, and for multiple myeloma. Four new categories of cancer were also investigated: the results for cancers of the liver and intrahepatic bile ducts and of the ovary and other uterine adnexa were suggestive of significant radiation effects, but the positive dose responses for cancers of the gallbladder and prostate were not significant. Due to diagnostic difficulties and the lack of evidence for radiogenic effects at these sites, the results for liver and ovarian cancers do not provide convincing evidence for radiogenic effects. With the exception of multiple myeloma, the relative risk (RR) of radiation-induced cancer mortality was greater for women than for men, for each nonleukemic cancer with a significant overall dose response. These differences can be attributed in large measure to differences in the background cancer mortality rates, which are generally much higher for men than women. For leukemia there was no significant sex difference in the RR, while for multiple myeloma women had a slightly, though nonsignificantly, lower RR than males. A statistically significant interaction (p = .008) between the effects of age ATB and attained age on radiation-related mortality was also observed for cancers other than leukemia. In particular, the initially large RRs seen in those who were young ATB have decreased with time, while the smaller RRs for those who were older ATB tended to increase. (author)

  2. The Relation between Big Five Traits and Well-being across the Life Span%不同年龄群体大五人格与幸福感关系

    Institute of Scientific and Technical Information of China (English)

    陈志霞; 李启明

    2014-01-01

    以毕生发展为研究视角,调查了3192位不同年龄群体被试,探讨不同年龄群体大五人格与幸福感的关系。结果发现:(1)各变量都存在显著的年龄效应,大五人格与主观幸福感相关显著;(2)在不同年龄群体里,神经质和开放性都能显著预测主观幸福感,且预测值随着年龄而增大,而外倾性、尽责性和宜人性对主观幸福感的预测存在年龄差异;(3)大五人格对主观幸福感的解释率随着年龄的增长而下降,到60岁之后其解释率上升;(4)年龄在大五人格与主观幸福感之间起了显著的调节作用。%In the current study, we examine the relationship between personality traits and subjective well-being and psy-chological well-being from a life span perspective.A total of 3192 Chinese residents took part in this study from 41 cities in the country 17 provinces and municipalities.And they completed the subjective well-being scale and big five-factor inventory.It took about 20 minutes to complete the questionnaires.The correlations among factors were calculated with SPSS 16.0 and Structural equation model was applied to deal with all data.In the analysis of struc-tural equation modeling, seven models were constructed.As predicted, personality traits were significantly associat-ed with subjective well-being with the different age groups of Chinese residents.And then Structural equation mod-els revealed that ages play a moderating role between personality traits and subjective well-being, and the total effect value was different.In conclusion, this research indicates that personality traits were associated with greater happiness across the life span, and personality traits were one of the best predictors.This study provides new in-sights into personal traits as predictors of well-being.Especially, this study addressed some limitations of previous studies.Importantly, this study also helps clarify questions about

  3. Extravehicular Activity Fact Sheet: An EVA Chronology

    Data.gov (United States)

    National Aeronautics and Space Administration — Walking to Olympus: An EVA Chronology chronicles the 154 EVAs conducted from March 1965 to April 1997. It is intended to make clear the crucial role played by EVA in...

  4. Atmospheric Heavy Metal Pollution - Development of Chronological ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 4. Atmospheric Heavy Metal Pollution - Development of Chronological Records and Geochemical Monitoring. Rohit Shrivastav. General Article Volume 6 Issue 4 April 2001 pp 62-68 ...

  5. Long Span Bridges in Scandinavia

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1998-01-01

    The first Scandinavian bridge with a span of more than 500 m was the Lillebælt Suspension Bridge opened to traffic in 1970.Art the end of the 20th century the longest span of any European bridge is found in the Storebælt East Bridge with a main span of 1624 m. Also the third longest span in Europe...... is found in Scandinavia - the 1210 m span of the Höga Kusten Bridge in Sweden.The Kvarnsund Bridge in Norway was at the completion in 1991 the longest cable-stayed bridge in the world, and the span of 530 m is still thge longest for cable-stayed bridges in concrete. The Øresund Bridge with its sapn of 490...

  6. A decrease in ubiquitination and resulting prolonged life-span of KIT underlies the KIT overexpression-mediated imatinib resistance of KIT mutation-driven canine mast cell tumor cells.

    Science.gov (United States)

    Kobayashi, Masato; Kuroki, Shiori; Kurita, Sena; Miyamoto, Ryo; Tani, Hiroyuki; Tamura, Kyoichi; Bonkobara, Makoto

    2017-10-01

    Overexpression of KIT is one of the mechanisms that contributes to imatinib resistance in KIT mutation-driven tumors. Here, the mechanism underlying this overexpression of KIT was investigated using an imatinib-sensitive canine mast cell tumor (MCT) line CoMS, which has an activating mutation in KIT exon 11. A KIT-overexpressing imatinib-resistant subline, rCoMS1, was generated from CoMS cells by their continuous exposure to increasing concentrations of imatinib. Neither a secondary mutation nor upregulated transcription of KIT was detected in rCoMS1 cells. A decrease in KIT ubiquitination, a prolonged KIT life-span, and KIT overexpression were found in rCoMS1 cells. These events were suppressed by withdrawal of imatinib and were re-induced by re‑treatment with imatinib. These findings suggest that imatinib elicited overexpression of KIT via suppression of its ubiquitination. These results also indicated that imatinib-induced overexpression of KIT in rCoMS1 cells was not a permanently acquired feature but was a reversible response of the cells. Moreover, the pan deubiquitinating enzyme inhibitor PR619 prevented imatinib induction of KIT overexpression, suggesting that the imatinib-induced decrease in KIT ubiquitination could be mediated by upregulation and/or activation of deubiquitinating enzyme(s). It may be possible that a similar mechanism of KIT overexpression underlies the acquisition of imatinib resistance in some human tumors that are driven by KIT mutation.

  7. Activation of the AMPK/Sirt1 pathway by a leucine-metformin combination increases insulin sensitivity in skeletal muscle, and stimulates glucose and lipid metabolism and increases life span in Caenorhabditis elegans.

    Science.gov (United States)

    Banerjee, Jheelam; Bruckbauer, Antje; Zemel, Michael B

    2016-11-01

    We have previously shown leucine (Leu) to activate Sirt1 by lowering its K M for NAD + , thereby amplifying the effects of other sirtuin activators and improving insulin sensitivity. Metformin (Met) converges on this pathway both indirectly (via AMPK) and by direct activation of Sirt1, and we recently found Leu to synergize with Met to improve insulin sensitivity and glycemic control while achieving ~80% dose-reduction in diet-induced obese mice. Accordingly, we sought here to define the mechanism of this interaction. Muscle cells C2C12 and liver cells HepG2 were used to test the effect of Met-Leu on Sirt1 activation. Caenorhabditis elegans was used for glucose utilization and life span studies. Leu (0.5mmol/L)+Met (50-100μmol/L) synergistically activated Sirt1 (pmetformin exerted no independent effect at any concentration (0.1-0.5mmol/L). Thus, Leu and Met synergize to enable Sirt1 activation at low NAD + concentrations (typical of energy replete states). Sirt1 and AMPK activations are required for Met-Leu's full action, which result in improvements in energy metabolism and insulin sensitivity. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Age Differences in Memory Span

    Science.gov (United States)

    Chi, Michelene T. H.

    1977-01-01

    Three experiments were conducted to determine processes underlying age differences in the level of recall in a memory-span task. Five-year-olds recalled fewer items than adults in memory-span tasks involving both familiar and unfamiliar faces, even though the use of rehearsal and recoding strategies was minimized for adults. (MS)

  9. Interplay among Gcn5, Sch9 and mitochondria during chronological aging of wine yeast is dependent on growth conditions.

    Directory of Open Access Journals (Sweden)

    Cecilia Picazo

    Full Text Available Saccharomyces cerevisiae chronological life span (CLS is determined by a wide variety of environmental and genetic factors. Nutrient limitation without malnutrition, i.e. dietary restriction, expands CLS through the control of nutrient signaling pathways, of which TOR/Sch9 has proven to be the most relevant, particularly under nitrogen deprivation. The use of prototrophic wine yeast allows a better understanding of the role of nitrogen in longevity in natural and more demanding environments, such as grape juice fermentation. We previously showed that acetyltransferase Gcn5, a member of the SAGA complex, has opposite effects on CLS under laboratory and winemaking conditions, and is detrimental under the latter. Here we demonstrate that integrity of the SAGA complex is necessary for prolonged longevity, as its dismantling by SPT20 deletion causes a drop in CLS under both laboratory and winemaking conditions. The sch9Δ mutant is long-lived in synthetic SC medium, as expected, and the combined deletion of GCN5 partially suppresses this phenotype. However it is short-lived in grape juice, likely due to its low nitrogen/carbon ratio. Therefore, unbalance of nutrients can be more relevant for life span than total amounts of them. Deletion of RTG2, which codes for a protein associated with Gcn5 and is a component of the mitochondrial retrograde signal, and which communicates mitochondrial dysfunction to the nucleus, is detrimental under laboratory, but not under winemaking conditions, where respiration seems not so relevant for longevity. Transcription factor Rgm1 was found to be a novel CLS regulator Sch9-dependently.

  10. Astronautics and aeronautics, 1978: A chronology

    Science.gov (United States)

    Janson, Bette R.

    1986-01-01

    This is the 18th in a series of annual chronologies of significant events in the fields of astronautics and aeronautics. Events covered are international as well as national and political as well as scientific and technical. This series is a reference work for historians, NASA personnel, government agencies, congressional staffs, and the media.

  11. Astronautics and aeronautics, 1985: A chronology

    Science.gov (United States)

    Janson, Bette R.

    1988-01-01

    This book is part of a series of annual chronologies of significant events in the fields of astronautics and aeronautics. Events covered are international as well as national, in political as well as scientific and technical areas. This series is an important reference work used by historians, NASA personnel, government agencies, and congressional staffs, as well as the media.

  12. Astronautics and aeronautics, 1976. A chronology

    Science.gov (United States)

    Ritchie, E. H.

    1984-01-01

    A chronology of events concerning astronautics and aeronautics for the year 1976 is presented. Some of the many and varied topics include the aerospace industry, planetary exploration, space transportation system, defense department programs, politics, and aerospace medicine. The entries are organized by the month and presented in a news release format.

  13. A Chronological History of Puerto Rico.

    Science.gov (United States)

    Tovar, Federico Ribes

    This book presents a chronological history of Puerto Rico from prehistory and discovery through December of 1972. It includes information on the persons and events that influenced the course of Puerto Rican history. A table of contents and a selective index are included. (Author/AM)

  14. Relationships between Categorical Perception of Phonemes, Phoneme Awareness, and Visual Attention Span in Developmental Dyslexia.

    Science.gov (United States)

    Zoubrinetzky, Rachel; Collet, Gregory; Serniclaes, Willy; Nguyen-Morel, Marie-Ange; Valdois, Sylviane

    2016-01-01

    We tested the hypothesis that the categorical perception deficit of speech sounds in developmental dyslexia is related to phoneme awareness skills, whereas a visual attention (VA) span deficit constitutes an independent deficit. Phoneme awareness tasks, VA span tasks and categorical perception tasks of phoneme identification and discrimination using a d/t voicing continuum were administered to 63 dyslexic children and 63 control children matched on chronological age. Results showed significant differences in categorical perception between the dyslexic and control children. Significant correlations were found between categorical perception skills, phoneme awareness and reading. Although VA span correlated with reading, no significant correlations were found between either categorical perception or phoneme awareness and VA span. Mediation analyses performed on the whole dyslexic sample suggested that the effect of categorical perception on reading might be mediated by phoneme awareness. This relationship was independent of the participants' VA span abilities. Two groups of dyslexic children with a single phoneme awareness or a single VA span deficit were then identified. The phonologically impaired group showed lower categorical perception skills than the control group but categorical perception was similar in the VA span impaired dyslexic and control children. The overall findings suggest that the link between categorical perception, phoneme awareness and reading is independent from VA span skills. These findings provide new insights on the heterogeneity of developmental dyslexia. They suggest that phonological processes and VA span independently affect reading acquisition.

  15. Relationships between Categorical Perception of Phonemes, Phoneme Awareness, and Visual Attention Span in Developmental Dyslexia.

    Directory of Open Access Journals (Sweden)

    Rachel Zoubrinetzky

    Full Text Available We tested the hypothesis that the categorical perception deficit of speech sounds in developmental dyslexia is related to phoneme awareness skills, whereas a visual attention (VA span deficit constitutes an independent deficit. Phoneme awareness tasks, VA span tasks and categorical perception tasks of phoneme identification and discrimination using a d/t voicing continuum were administered to 63 dyslexic children and 63 control children matched on chronological age. Results showed significant differences in categorical perception between the dyslexic and control children. Significant correlations were found between categorical perception skills, phoneme awareness and reading. Although VA span correlated with reading, no significant correlations were found between either categorical perception or phoneme awareness and VA span. Mediation analyses performed on the whole dyslexic sample suggested that the effect of categorical perception on reading might be mediated by phoneme awareness. This relationship was independent of the participants' VA span abilities. Two groups of dyslexic children with a single phoneme awareness or a single VA span deficit were then identified. The phonologically impaired group showed lower categorical perception skills than the control group but categorical perception was similar in the VA span impaired dyslexic and control children. The overall findings suggest that the link between categorical perception, phoneme awareness and reading is independent from VA span skills. These findings provide new insights on the heterogeneity of developmental dyslexia. They suggest that phonological processes and VA span independently affect reading acquisition.

  16. Relationships between Categorical Perception of Phonemes, Phoneme Awareness, and Visual Attention Span in Developmental Dyslexia

    Science.gov (United States)

    Zoubrinetzky, Rachel; Collet, Gregory; Serniclaes, Willy; Nguyen-Morel, Marie-Ange; Valdois, Sylviane

    2016-01-01

    We tested the hypothesis that the categorical perception deficit of speech sounds in developmental dyslexia is related to phoneme awareness skills, whereas a visual attention (VA) span deficit constitutes an independent deficit. Phoneme awareness tasks, VA span tasks and categorical perception tasks of phoneme identification and discrimination using a d/t voicing continuum were administered to 63 dyslexic children and 63 control children matched on chronological age. Results showed significant differences in categorical perception between the dyslexic and control children. Significant correlations were found between categorical perception skills, phoneme awareness and reading. Although VA span correlated with reading, no significant correlations were found between either categorical perception or phoneme awareness and VA span. Mediation analyses performed on the whole dyslexic sample suggested that the effect of categorical perception on reading might be mediated by phoneme awareness. This relationship was independent of the participants’ VA span abilities. Two groups of dyslexic children with a single phoneme awareness or a single VA span deficit were then identified. The phonologically impaired group showed lower categorical perception skills than the control group but categorical perception was similar in the VA span impaired dyslexic and control children. The overall findings suggest that the link between categorical perception, phoneme awareness and reading is independent from VA span skills. These findings provide new insights on the heterogeneity of developmental dyslexia. They suggest that phonological processes and VA span independently affect reading acquisition. PMID:26950210

  17. Establishment of an absolute chronology for the 18th Egyptian Dynasty

    International Nuclear Information System (INIS)

    Quiles, A.

    2011-01-01

    The establishment of an absolute chronology for Ancient Egypt is an ambition which has concentrated efforts of many scholars since the beginning of Egyptology. Thanks to historical and archaeological documents, a relative chronology of the kings has been built. Only some astrophysical points and synchronisms listed in texts (Greek and Egyptian sources) have given some ankle points which have led to some propositions of absolute chronology. At first, we will see how we can re-calculate some ankle points by using Sothic dating and modelling lunar dates with a Bayesian approach. Then, radiocarbon measurements have been done at Laboratoire de Mesure du Carbone 14 (CEA Saclay) on Egyptian short life materials like plants or twigs. These objects come from the Louvre Museum and are attributed to a particular reign and a precise period. With a Bayesian approach, these analyses have been combined with the known succession and length of the reign. Besides, Sothic and lunar dates have been incorporated as a prior in the model. It has led to propose an absolute chronology for the 18th dynasty. Finally, we will discuss the agreement between our results and archaeological evidence and will see if this chronology can highlight points where Egyptologists disagree. (author)

  18. Radiocarbon measurements on submerged forest floating chronologies

    International Nuclear Information System (INIS)

    Campbell, J.A.; Baxter, M.S.

    1979-01-01

    It is stated that the submerged forests along the west coast of England and Wales provide a unique source of wood for radiocarbon/ dendrochronological studies. 14 C age determinations are reported on sequential growth increments from three 'gloating' chronologies. A sampling frequency of approximately 10 samples per century was used. Fluctuations in atmospheric 14 C levels of 2 to 3% over several decades can occur, these variations being superimposed on a smoothly changing trend. (author)

  19. A chronology of librarianship, 1960-2000

    CERN Document Server

    Wilhite, Jeffrey M

    2009-01-01

    This book covers all areas of library literature that inform the history of librarianship and ranges over multiple continents. Its broad scope lends itself to wide use by scholars and students of library history and library literature. The chronology is presented in a dictionary format and separated into decades. It is complemented by a comprehensive bibliography and both subject and name indexes, which are cross-listed for ease of use.

  20. Spatial variability in growth-increment chronologies of long-lived freshwater mussels: Implications for climate impacts and reconstructions

    Science.gov (United States)

    Black, Bryan A.; Dunham, Jason B.; Blundon, Brett W.; Raggon, Mark F.; Zima, Daniela

    2010-01-01

    Estimates of historical variability in river ecosystems are often lacking, but long-lived freshwater mussels could provide unique opportunities to understand past conditions in these environments. We applied dendrochronology techniques to quantify historical variability in growth-increment widths in valves (shells) of western pearlshell freshwater mussels (Margaritifera falcata). A total of 3 growth-increment chronologies, spanning 19 to 26 y in length, were developed. Growth was highly synchronous among individuals within each site, and to a lesser extent, chronologies were synchronous among sites. All 3 chronologies negatively related to instrumental records of stream discharge, while correlations with measures of water temperature were consistently positive but weaker. A reconstruction of stream discharge was performed using linear regressions based on a mussel growth chronology and the regional Palmer Drought Severity Index (PDSI). Models based on mussel growth and PDSI yielded similar coefficients of prediction (R2Pred) of 0.73 and 0.77, respectively, for predicting out-ofsample observations. From an ecological perspective, we found that mussel chronologies provided a rich source of information for understanding climate impacts. Responses of mussels to changes in climate and stream ecosystems can be very site- and process-specific, underscoring the complex nature of biotic responses to climate change and the need to understand both regional and local processes in projecting climate impacts on freshwater species.

  1. A Distributed Spanning Tree Algorithm

    DEFF Research Database (Denmark)

    Johansen, Karl Erik; Jørgensen, Ulla Lundin; Nielsen, Sven Hauge

    We present a distributed algorithm for constructing a spanning tree for connected undirected graphs. Nodes correspond to processors and edges correspond to two-way channels. Each processor has initially a distinct identity and all processors perform the same algorithm. Computation as well...

  2. A distributed spanning tree algorithm

    DEFF Research Database (Denmark)

    Johansen, Karl Erik; Jørgensen, Ulla Lundin; Nielsen, Svend Hauge

    1988-01-01

    We present a distributed algorithm for constructing a spanning tree for connected undirected graphs. Nodes correspond to processors and edges correspond to two way channels. Each processor has initially a distinct identity and all processors perform the same algorithm. Computation as well as comm...

  3. The optimum spanning catenary cable

    Science.gov (United States)

    Wang, C. Y.

    2015-03-01

    A heavy cable spans two points in space. There exists an optimum cable length such that the maximum tension is minimized. If the two end points are at the same level, the optimum length is 1.258 times the distance between the ends. The optimum lengths for end points of different heights are also found.

  4. The SPAN cookbook: A practical guide to accessing SPAN

    Science.gov (United States)

    Mason, Stephanie; Tencati, Ronald D.; Stern, David M.; Capps, Kimberly D.; Dorman, Gary; Peters, David J.

    1990-01-01

    This is a manual for remote users who wish to send electronic mail messages from the Space Physics Analysis Network (SPAN) to scientific colleagues on other computer networks and vice versa. In several instances more than one gateway has been included for the same network. Users are provided with an introduction to each network listed with helpful details about accessing the system and mail syntax examples. Also included is information on file transfers, remote logins, and help telephone numbers.

  5. Detailed free span assessment for Mexilhao flow lines

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Antonio; Franco, Luciano; Eigbe, Uwa; BomfimSilva, Carlos [INTECSEA, Houston, TX (United States); Escudero, Carlos [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2009-07-01

    The subsea gas production system of Mexilhao Field SPS-35, Santos Basin, offshore Brazil, is composed basically of two rigid 12.75 inches production flow lines approximately 21 km long installed in a fairly rough seabed. During the basic design, the free span assessment was performed considering the maximum allowable free span length determined by the response model proposed by DNV-RP-F105. This approach resulted in a large number of predicted free span requiring corrections, leading to a higher capital cost for the project. In this sense, a detailed free span VIV fatigue assessment was proposed, considering multi-spans and multi-mode effects and also the post lay survey data. The assessment followed the DNV-RP-F105 recommendations for multi-spans and multi-mode effects, using Finite Element Analysis to determine the natural frequencies, mode shapes and corresponding stresses associated with the mode shapes. The assessment was performed in three stages, the first during the detailed design as part of the bottom roughness analysis using the expected residual pipelay tension. The second stage was performed after pipelay, considering the post-lay survey data, where the actual requirements for span correction were determined. Actual pipelay tension was used and seabed soil stiffness adjusted in the model to match the as-laid pipeline profile obtained from the survey data. The first and second stage assessments are seamlessly automated to speed up the evaluation process and allow for quick response in the field, which was important to keep the construction vessel time minimized. The third stage was performed once the corrections of the spans were made and the purpose was to confirm that the new pipeline configuration along the supported spans had sufficient fatigue life for the temporary and operational phases. For the assessment of all three stages, the probability of occurrence and directionality of the near bottom current was considered to improve prediction of the

  6. Spanning Tree Based Attribute Clustering

    DEFF Research Database (Denmark)

    Zeng, Yifeng; Jorge, Cordero Hernandez

    2009-01-01

    Attribute clustering has been previously employed to detect statistical dependence between subsets of variables. We propose a novel attribute clustering algorithm motivated by research of complex networks, called the Star Discovery algorithm. The algorithm partitions and indirectly discards...... inconsistent edges from a maximum spanning tree by starting appropriate initial modes, therefore generating stable clusters. It discovers sound clusters through simple graph operations and achieves significant computational savings. We compare the Star Discovery algorithm against earlier attribute clustering...

  7. Lake trout otolith chronologies as multidecadal indicators of high-latitude freshwater ecosystems

    Science.gov (United States)

    Black, B.A.; Von Biela, V.R.; Zimmerman, C.E.; Brown, Randy J.

    2013-01-01

    High-latitude ecosystems are among the most vulnerable to long-term climate change, yet continuous, multidecadal indicators by which to gauge effects on biology are scarce, especially in freshwater environments. To address this issue, dendrochronology (tree-ring analysis) techniques were applied to growth-increment widths in otoliths from lake trout (Salvelinus namaycush) from the Chandler Lake system, Alaska (68.23°N, 152.70°W). All otoliths were collected in 1987 and exhibited highly synchronous patterns in growth-increment width. Increments were dated, the widths were measured, and age-related growth declines were removed using standard dendrochronology techniques. The detrended time series were averaged to generate an annually resolved chronology, which continuously spanned 1964–1984. The chronology positively and linearly correlated with August air temperature over the 22-year interval (p fish metabolic rate or lake productivity. Given the broad distribution of lake trout within North America, this study suggests that otolith chronologies could be used to examine responses between freshwater ecosystems and environmental variability across a range of temporal and spatial scales.

  8. Lake trout otolith chronologies as multidecadal indicators of high-latitude freshwater ecosystems

    Science.gov (United States)

    Black, B.A.; Von Biela, V.R.; Zimmerman, C.E.; Brown, Randy J.

    2013-01-01

    High-latitude ecosystems are among the most vulnerable to long-term climate change, yet continuous, multidecadal indicators by which to gauge effects on biology are scarce, especially in freshwater environments. To address this issue, dendrochronology (tree-ring analysis) techniques were applied to growth-increment widths in otoliths from lake trout (Salvelinus namaycush) from the Chandler Lake system, Alaska (68.23°N, 152.70°W). All otoliths were collected in 1987 and exhibited highly synchronous patterns in growth-increment width. Increments were dated, the widths were measured, and age-related growth declines were removed using standard dendrochronology techniques. The detrended time series were averaged to generate an annually resolved chronology, which continuously spanned 1964–1984. The chronology positively and linearly correlated with August air temperature over the 22-year interval (p otolith chronologies could be used to examine responses between freshwater ecosystems and environmental variability across a range of temporal and spatial scales.

  9. Linking and Cutting Spanning Trees

    Directory of Open Access Journals (Sweden)

    Luís M. S. Russo

    2018-04-01

    Full Text Available We consider the problem of uniformly generating a spanning tree for an undirected connected graph. This process is useful for computing statistics, namely for phylogenetic trees. We describe a Markov chain for producing these trees. For cycle graphs, we prove that this approach significantly outperforms existing algorithms. For general graphs, experimental results show that the chain converges quickly. This yields an efficient algorithm due to the use of proper fast data structures. To obtain the mixing time of the chain we describe a coupling, which we analyze for cycle graphs and simulate for other graphs.

  10. Supported Lead in Pb-210 Chronology

    Energy Technology Data Exchange (ETDEWEB)

    Pittauerova, D.; Hettwig, B.; Fischer, H. W. [Institute of Environmental Physics, University of Bremen, Bremen (Germany)

    2013-07-15

    A widely applied method of supported lead estimation in sediments using gamma spectrometric {sup 226}Ra determination via {sup 222}Rn short lived daughter products relies on radioactive equilibrium between {sup 226}Ra and {sup 222}Rn being established after sealing the samples. Advantages and disadvantages of methods of {sup 226}Ra estimation in sediments, using either {sup 222}Rn daughter products or direct estimation by 186.2 keV gamma emissions are discussed. An equilibrium experiment was performed using test samples and in one case radioactive equilibrium was not reached. On a theoretical sediment profile it was shown how systematic errors in supported {sup 210}Pb estimation can lead to incorrect interpretations of {sup 210}Pb{sub xs} profiles and therefore affect {sup 210}Pb derived chronologies. (author)

  11. Revision of the Martian relative age chronology

    International Nuclear Information System (INIS)

    Barlow, N.G.

    1987-01-01

    This study has provided a more detailed chronology than currently exists in the literature and has created some changes to the currently accepted geological evolutionary sequence of Mars. The period of heavy bombardment, although dominated by impact processes, experienced many forms of volcanic activity and at least one episode of intense fracturing. Most small volcanic constructs and the ridged plains regions are found to date from this early period, contrary to common belief. The fracturing and dissection of the highlands helps to provide further constraints on the timing of events such as the formation of the hemispheric dichotomy and the formation of the Tharsis Bulge. The northern plains are found to consist of a number of differently aged regions. The difference in age between the chaotic terrain and the outflow channels together with differences in the distribution curves among craters of various erosional states found on the channels support the theory of episodic periods of flooding

  12. Jewish Holocaust Histories and the Work of Chronological Narratives

    Science.gov (United States)

    Silverstein, Jordana

    2012-01-01

    This article examines the ways that, in Holocaust education in Jewish schools in Melbourne and New York at the beginning of the 21st century, knowledge of the Holocaust is transferred to students in chronological form. It begins by asking: What work do chronological narratives do within the Holocaust historical narratives offered within Jewish…

  13. Determinantal spanning forests on planar graphs

    OpenAIRE

    Kenyon, Richard

    2017-01-01

    We generalize the uniform spanning tree to construct a family of determinantal measures on essential spanning forests on periodic planar graphs in which every component tree is bi-infinite. Like the uniform spanning tree, these measures arise naturally from the laplacian on the graph. More generally these results hold for the "massive" laplacian determinant which counts rooted spanning forests with weight $M$ per finite component. These measures typically have a form of conformal invariance, ...

  14. Enhancing reading performance through action video games: the role of visual attention span.

    Science.gov (United States)

    Antzaka, A; Lallier, M; Meyer, S; Diard, J; Carreiras, M; Valdois, S

    2017-11-06

    Recent studies reported that Action Video Game-AVG training improves not only certain attentional components, but also reading fluency in children with dyslexia. We aimed to investigate the shared attentional components of AVG playing and reading, by studying whether the Visual Attention (VA) span, a component of visual attention that has previously been linked to both reading development and dyslexia, is improved in frequent players of AVGs. Thirty-six French fluent adult readers, matched on chronological age and text reading proficiency, composed two groups: frequent AVG players and non-players. Participants performed behavioural tasks measuring the VA span, and a challenging reading task (reading of briefly presented pseudo-words). AVG players performed better on both tasks and performance on these tasks was correlated. These results further support the transfer of the attentional benefits of playing AVGs to reading, and indicate that the VA span could be a core component mediating this transfer. The correlation between VA span and pseudo-word reading also supports the involvement of VA span even in adult reading. Future studies could combine VA span training with defining features of AVGs, in order to build a new generation of remediation software.

  15. Preliminary study of the chronology of the sedimentation process in lakes

    International Nuclear Information System (INIS)

    Patrocinio Junior, Antonio C.; Andrello, Avacir C.

    2009-01-01

    The soil erosion accelerated which produces the presence of sediment in rivers is one of the main environmental problems and represents a challenge for the sustainable use of soil and water resources. The problems associated with the increased sediments production are mainly related to the rivers siltation, reduced storage capacity of dams and reservoirs and reduction in the quality of aquatic environment. Thus, further information on sedimentation rates in lakes and reservoirs are required, as a parameter for estimating the chronology of production rates of sediment. Therefore, methods to establish the chronology of recent sediments are central base for such research. The cesium-137 is an artificial radionuclide with a half life of 30.2 years, inserted in the environment through the 'fallout' radioactive between the 1950's and 1970's, with two predominant peaks of deposition in 1959 and 1964. The basis for using the cesium-137 in this context (chronology of sediments) is that the cesium-137 is rapidly and strongly adsorbed to fine particles of soil and its distribution in the sediment profile directly reflects the chronology of sediment deposition. The purpose of this work is to use the cesium-137 profile in lake sediments to assess the history of deposition and to obtain information about the erosive process. For this, lake sediments of a mini-hydroelectric power plant built in the 1940's in the city of Londrina-PR were analyzed, showing that cesium-137 can be used as a source of data for chronological assessment of erosive processes occurring in the vicinity of the lake. (author)

  16. On the size of monotone span programs

    NARCIS (Netherlands)

    Nikov, V.S.; Nikova, S.I.; Preneel, B.; Blundo, C.; Cimato, S.

    2005-01-01

    Span programs provide a linear algebraic model of computation. Monotone span programs (MSP) correspond to linear secret sharing schemes. This paper studies the properties of monotone span programs related to their size. Using the results of van Dijk (connecting codes and MSPs) and a construction for

  17. Perceived Changes in Well-Being: The Role of Chronological Age, Target Age, and Type of Measure

    Science.gov (United States)

    Okun, Morris A.; Dittburner, Julie L.; Huff, Barbara P.

    2006-01-01

    The goal of this study is to investigate whether perceived changes in one's well-being from the present to the future are related to chronological age, target age, and type of measure (psychological well-being versus life satisfaction). Young adults (N = 114) rated their current well-being and their future well-being at one of three target ages…

  18. Cell-autonomous mechanisms of chronological aging in the yeast Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Anthony Arlia-Ciommo

    2014-05-01

    Full Text Available A body of evidence supports the view that the signaling pathways governing cellular aging – as well as mechanisms of their modulation by longevity-extending genetic, dietary and pharmacological interventions - are conserved across species. The scope of this review is to critically analyze recent advances in our understanding of cell-autonomous mechanisms of chronological aging in the budding yeast Saccharomyces cerevisiae. Based on our analysis, we propose a concept of a biomolecular network underlying the chronology of cellular aging in yeast. The concept posits that such network progresses through a series of lifespan checkpoints. At each of these checkpoints, the intracellular concentrations of some key intermediates and products of certain metabolic pathways - as well as the rates of coordinated flow of such metabolites within an intricate network of intercompartmental communications - are monitored by some checkpoint-specific ′′master regulator′′ proteins. The concept envisions that a synergistic action of these master regulator proteins at certain early-life and late-life checkpoints modulates the rates and efficiencies of progression of such processes as cell metabolism, growth, proliferation, stress resistance, macromolecular homeostasis, survival and death. The concept predicts that, by modulating these vital cellular processes throughout lifespan (i.e., prior to an arrest of cell growth and division, and following such arrest, the checkpoint-specific master regulator proteins orchestrate the development and maintenance of a pro- or anti-aging cellular pattern and, thus, define longevity of chronologically aging yeast.

  19. Cell-autonomous mechanisms of chronological aging in the yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Arlia-Ciommo, Anthony; Leonov, Anna; Piano, Amanda; Svistkova, Veronika; Titorenko, Vladimir I

    2014-05-27

    A body of evidence supports the view that the signaling pathways governing cellular aging - as well as mechanisms of their modulation by longevity-extending genetic, dietary and pharmacological interventions - are conserved across species. The scope of this review is to critically analyze recent advances in our understanding of cell-autonomous mechanisms of chronological aging in the budding yeast Saccharomyces cerevisiae . Based on our analysis, we propose a concept of a biomolecular network underlying the chronology of cellular aging in yeast. The concept posits that such network progresses through a series of lifespan checkpoints. At each of these checkpoints, the intracellular concentrations of some key intermediates and products of certain metabolic pathways - as well as the rates of coordinated flow of such metabolites within an intricate network of intercompartmental communications - are monitored by some checkpoint-specific "master regulator" proteins. The concept envisions that a synergistic action of these master regulator proteins at certain early-life and late-life checkpoints modulates the rates and efficiencies of progression of such processes as cell metabolism, growth, proliferation, stress resistance, macromolecular homeostasis, survival and death. The concept predicts that, by modulating these vital cellular processes throughout lifespan (i.e., prior to an arrest of cell growth and division, and following such arrest), the checkpoint-specific master regulator proteins orchestrate the development and maintenance of a pro- or anti-aging cellular pattern and, thus, define longevity of chronologically aging yeast.

  20. Extended attention span training system

    Science.gov (United States)

    Pope, Alan T.; Bogart, Edward H.

    1991-01-01

    Attention Deficit Disorder (ADD) is a behavioral disorder characterized by the inability to sustain attention long enough to perform activities such as schoolwork or organized play. Treatments for this disorder include medication and brainwave biofeedback training. Brainwave biofeedback training systems feed back information to the trainee showing him how well he is producing the brainwave pattern that indicates attention. The Extended Attention Span Training (EAST) system takes the concept a step further by making a video game more difficult as the player's brainwaves indicate that attention is waning. The trainee can succeed at the game only by maintaining an adequate level of attention. The EAST system is a modification of a biocybernetic system that is currently being used to assess the extent to which automated flight management systems maintain pilot engagement. This biocybernetic system is a product of a program aimed at developing methods to evaluate automated flight deck designs for compatibility with human capabilities. The EAST technology can make a contribution in the fields of medical neuropsychology and neurology, where the emphasis is on cautious, conservative treatment of youngsters with attention disorders.

  1. Some Metabolites Act as Second Messengers in Yeast Chronological Aging

    Directory of Open Access Journals (Sweden)

    Karamat Mohammad

    2018-03-01

    Full Text Available The concentrations of some key metabolic intermediates play essential roles in regulating the longevity of the chronologically aging yeast Saccharomyces cerevisiae. These key metabolites are detected by certain ligand-specific protein sensors that respond to concentration changes of the key metabolites by altering the efficiencies of longevity-defining cellular processes. The concentrations of the key metabolites that affect yeast chronological aging are controlled spatially and temporally. Here, we analyze mechanisms through which the spatiotemporal dynamics of changes in the concentrations of the key metabolites influence yeast chronological lifespan. Our analysis indicates that a distinct set of metabolites can act as second messengers that define the pace of yeast chronological aging. Molecules that can operate both as intermediates of yeast metabolism and as second messengers of yeast chronological aging include reduced nicotinamide adenine dinucleotide phosphate (NADPH, glycerol, trehalose, hydrogen peroxide, amino acids, sphingolipids, spermidine, hydrogen sulfide, acetic acid, ethanol, free fatty acids, and diacylglycerol. We discuss several properties that these second messengers of yeast chronological aging have in common with second messengers of signal transduction. We outline how these second messengers of yeast chronological aging elicit changes in cell functionality and viability in response to changes in the nutrient, energy, stress, and proliferation status of the cell.

  2. Chronology of petroleum geophysics; Sekiyu butsuri tansa nenpyo

    Energy Technology Data Exchange (ETDEWEB)

    Kametani, T

    1996-10-01

    A table, chronology of petroleum geophysics in overseas and in Japan, has been prepared for the convenience of checking events, which are thought to be important as notable affairs in application, success, and technical innovation. In overseas, successes in the 1920s were remarkable, when the US modern geophysical exploration made a start. Successes in determining the position of exploratory drilling by means of the gravity torsion balance, fan shooting seismic refraction method, and seismic reflection method occurred one after another. The USA has kept its situation stably as the number one by the seismic reflection method occurred most lately, and its life has been further elongated by adopting digital techniques. The CDP technique which became to be used simultaneously, and the seismic sources without using explosives, such as vibro-seismic source and air gun, extended the success of digital techniques drastically. In the future, the progress of 3-D exploration technology is expected. In Japan, about 18 years lag in the seismic reflection method is observed when compared with the USA. Japan has provided leading techniques in the shallow layer seismic reflection method and S-wave exploration. 40 refs., 1 tab.

  3. Astronautics and Aeronautics, 1986-1990: A Chronology

    Science.gov (United States)

    Gawdiak, Ihor Y.; Miro, Ramon J.; Stueland, Sam

    1997-01-01

    This chronology of events in aeronautics, aviation, space science, and space exploration was prepared by the Federal Research Division of the LibrarY of Congress for the History Division of the National Aeronautics and Space Administration (NASA). It covers the years 1996-1990 and continues the series of annual chronologies published by NASA. The present volume returns to the format used in the Astronautics and Aeronautics, 1979-1984: A Chronology volume. It also integrates in a single table the information presented in two or three previous publications.

  4. Astronautics and Aeronautics, 1991-1995: A Chronology

    Science.gov (United States)

    Gawdiak, Ihor Y. (Compiler); Shetland, Charles (Compiler)

    2000-01-01

    This chronology of events in aeronautics, aviation, space science, and space exploration was prepared by the Federal Research Division of the Library of Congress and RSIS for the History Division of the National Aeronautics and Space Administration (NASA). It covers the years 1991-1995 and continues the series of annual chronologies published by NASA. The present volume uses the format of the previous edition of this series, Astronautics and Aeronautics, 1986-1990: A Chronology. It also integrates, in the appendices, information presented in previous publication

  5. Spanning forests and the vector bundle Laplacian

    OpenAIRE

    Kenyon, Richard

    2011-01-01

    The classical matrix-tree theorem relates the determinant of the combinatorial Laplacian on a graph to the number of spanning trees. We generalize this result to Laplacians on one- and two-dimensional vector bundles, giving a combinatorial interpretation of their determinants in terms of so-called cycle rooted spanning forests (CRSFs). We construct natural measures on CRSFs for which the edges form a determinantal process. ¶ This theory gives a natural generalization of the spanning tre...

  6. A chronological framework connecting the early Upper Palaeolithic across the Central Asian piedmont.

    Science.gov (United States)

    Fitzsimmons, Kathryn E; Iovita, Radu; Sprafke, Tobias; Glantz, Michelle; Talamo, Sahra; Horton, Katharine; Beeton, Tyler; Alipova, Saya; Bekseitov, Galymzhan; Ospanov, Yerbolat; Deom, Jean-Marc; Sala, Renato; Taimagambetov, Zhaken

    2017-12-01

    Central Asia has delivered significant paleoanthropological discoveries in the past few years. New genetic data indicate that at least two archaic human species met and interbred with anatomically modern humans as they arrived into northern Central Asia. However, data are limited: known archaeological sites with lithic assemblages generally lack human fossils, and consequently identifying the archaeological signatures of different human groups, and the timing of their occupation, remains elusive. Reliable chronologic data from sites in the region, crucial to our understanding of the timing and duration of interactions between different human species, are rare. Here we present chronologies for two open air Middle to Upper Palaeolithic (UP) sequences from the Tien Shan piedmont in southeast Kazakhstan, Maibulak and Valikhanova, which bridge southern and northern Central Asia. The chronologies, based on both quartz optically stimulated luminescence (OSL) and polymineral post-infrared infrared luminescence (pIR-IRSL) protocols, demonstrate that technological developments at the two sites differ substantially over the ∼47-19 ka time span. Some of the innovations typically associated with the earliest UP in the Altai or other parts of northeast Asia are also present in the Tien Shan piedmont. We caution against making assumptions about the directionality of spread of these technologies until a larger, better defined database of transitional sites in the region is available. Connections between the timing of occupation of regions, living area setting and paleoenvironmental conditions, while providing hypotheses worth exploring, remain inconclusive. We cautiously suggest a trend towards increasing occupation of open air sites across the Central Asian piedmont after ∼40 ka, corresponding to more humid climatic conditions which nevertheless included pulses of dust deposition. Human occupation persisted into the Last Glacial Maximum, despite cooler, and possibly drier

  7. Changes in Anti-Müllerian Hormone (AMH) throughout the Life Span: A Population-Based Study of 1027 Healthy Males from Birth (Cord Blood) to the Age of 69 Years

    DEFF Research Database (Denmark)

    Aksglæde, Lise; Sørensen, K; Boas, Malene

    2010-01-01

    Context: Anti-Mu¨ llerian hormone (AMH), which is secreted by immature Sertoli cells, triggers the involution of the fetalMu¨ llerian ducts.AMHis a testis-specific marker used for diagnosis in infants with ambiguous genitalia or bilateral cryptorchidism. Aim: The aim of the study was to describe...... the ontogeny of AMH secretion through life in healthy males. Setting:This was a population-based study of healthy volunteers. Participants: Participants included 1027 healthy males from birth (cord blood) to 69 yr. A subgroup was followed up longitudinally through the infantile minipuberty [(in cord blood......AMHwas above the detection limit in all samples with a marked variation according to age and pubertal status. The median AMH level in cord blood was 148 pmol/liter and increased significantly to the highest observed levels at 3 months (P 0.0001). AMH declined at 12 months (P 0.0001) and remained...

  8. Astronautics and aeronautics, 1970. Chronology on science, technology, and policy

    Science.gov (United States)

    1972-01-01

    An immediate reference to aerospace-related events of 1970 is provided to help historians in preserving historical accuracy and precision. Chronologies of major NASA launches, and manned space flights for 1970 are included.

  9. Astronautics and Aeronautics, 1979-1984: A chronology

    Science.gov (United States)

    Janson, Bette R.; Ritchie, Eleanor H.

    1989-01-01

    This volume of the Astronautics and Aeronautics series covers 1979 through 1984. The series provides a chronological presentation of all significant events and developments in space exploration and the administration of the space program during the period covered.

  10. Chronological changes in hypertensive intracerebral hemorrhages

    International Nuclear Information System (INIS)

    Takasugi, Shinsuke; Kashihara, Michiharu; Okamoto, Junji; Hondo, Hideki; Yamashita, Shigeru

    1983-01-01

    The clinical series consisted of 28 patients with hypertensive intracerebral hematoma observed in the natural course from 1976 through 1978. A total of 114 repeated computer tomographic (CT) examinations were made with an EMI-1010 or an ACTA-0100 scanner. The experimental series consisted of 26 adult mongrel dogs with intracerebral hematoma near the basal ganglia. In 20 dogs, autopsy and histological examinations were performed, and in 12 dogs a total of 31 repeated CT examinations were carried out with an EMI scanner (matrix 320 x 320, high-definition scan). In the clinical series, the time of the decrease in density beginning in the periphery of the hematoma, like the first appearance of ring enhancement and its concentric concentration toward the center of the hematoma, was not affected by the size of the hematoma. However, the time when the intracerebral hematoma was resolved did vary with the size of the hematoma. In the experimental series, the tissue reaction near the periphery of the intracerebral hematoma seemed to be a constant process. First, a necrotic layer appeared, and then this was replaced by immature connective tissue with granular cells, newly formed vessels, and reticulin fibers; finally, the immature layer was gradually transformed into mature connective tissue with collagenous fibers. Moreover, this process of change was not related to the size of the hematoma. The following correlations were suggested by a chronological observation of the CT images and the histological appearance: 1) acute stage - homogeneous high-density extending to the periphery, apperance of a necrotic layer; 2) subacute stage - decreased density spreading from the periphery and formation of ring enhancement, apperance of immature connective tissue with reticulin fibers; 3) chronic stage - concentric concentration of ring enhancement, mature connective tissue with collagenous fibers

  11. The EASTNET Project: Extending the Network of Climate-Sensitive Tree-Ring Chronologies From the Eastern United States for Reconstructing the Spatio-Temporal Characteristics of Climate and Drought Over the Past Millennium

    Science.gov (United States)

    Buckley, B. M.; Cook, E. R.

    2002-12-01

    Recently, a network of gridded PDSI reconstructions for the contiguous United States was produced, based on the available network of drought-sensitive tree-ring chronologies (Cook et al. 1999). Analyses were constrained to the common period of 1700 - 1979 due to the limitations of the available tree-ring data. While several chronologies from the western U.S. span 1,000 years or more, very few chronologies from the eastern U.S. covered even the past 500 years. The objective of this project, funded by the National Science Foundation's ESH program, is to extend the tree-ring chronology network from the eastern U.S. with chronologies spanning the past 500-1,000 years. This aim is being achieved by sampling in areas that have escaped the effects of development, logging and major disturbance such as fire. The two main target species are Thuja occidentalis (eastern white cedar) and Juniperus virginiana (eastern red cedar). The primary terrain types are on cliffs, rocky outcrops, and other areas that have been difficult to access. We have already developed chronologies from Wisconsin, New Hampshire, Pennsylvania, West Virginia, and Virginia that span from 500 to 1500 years. The temporal depth of these chronologies is being extended through the exploitation of "sub-fossil" wood found at these sites, in the form of standing-dead stems and downed and buried logs. We are also currently pursuing leads in Maine, Vermont, Massachusetts, Connecticut, New York, New Jersey Pennsylvania, Kentucky and North Carolina where old cedar trees have either been reported or where terrain types match criteria developed for this project. In this paper we discuss the current status of the network, and explore the spatio-temporal characteristics of climate and drought across the eastern US for the past 500 years and more. We use our preliminary network to explore the regional expression of climate anomalies such as drought. Our analyses so far demonstrates multicentennial variability suggestive

  12. Chronology of Chichen Izta, evidences by thermoluminescence

    International Nuclear Information System (INIS)

    Ramirez, A.; Schaaf, P.; Gonzalez, P.R.; Chung, H.

    2002-01-01

    The establishment of the chronology of Chichen Itza is argued by its stylistic evocations, architectural and iconographical as well as its history related in the sources, as the Chilam Balam, where is named the arrival of foreign tribes as the Xiu and the Itzaes and its settlement in Chichen Itza as well as the return to its origin place. The material evidence of such transition is reflected in the ceramic change of the Pizarra Puuc to the Pizarra Chichen, however, in 13 stratigraphic wells realized in different points of Chichen Itza, it was not found evidence of the layer of the Pizarra Puuc period. In this work the obtained ages of dating by thermoluminescence (TL) are presented, of four samples of ceramics found in the different wells. When our results are compared with the estimated ages for the different groups of ceramics, it was observed that none of they corresponded to the Pizarra Puuc period. These results strenghten the observations realized during excavations, causing the suggestion of new inferences related to the Chichen Itza boom and its relationship with the Maya Classic Period. The used technique for the TL dating was that of fine grain. The interval of artificial dose, of beta radiation of Strontium 90 was between 2 and 30 Gy. The TL signal was obtained heating the samples at 10 C/s until reaching 500 C in the TL Daybreak reader equipment. In order to know the annual dose rate of concentration of potassium ( 40 K) by means of the microanalysis technique in the scanning electron microscope was determined, while the uranium content (2 38 U) and thorium ( 232 Th) were determined by means of the neutron activation analysis technique using the TRIGA Mark III nuclear reactor. The contribution of the gamma radiation of the soil as well as the contribution of the cosmic radiation was measured with TL dosemeters of CaSO 4 :Dy + Ptfe once the paleodose was known and the annual dose rate of each sample of its age was estimated. (Author)

  13. Gamma spectrometry for chronology of recent sediments

    International Nuclear Information System (INIS)

    Pittauerova, Daniela

    2013-01-01

    This thesis deals with several aspects of gamma spectrometric analysis of natural and artificial isotopes in sediments and their use as tracers for qualification and quantification of accumulation and mixing processes in different aquatic environments. Sediment cores from three distinct areas including terrigenous sediments deposited on the continental slope off NW Africa, deep sea sediments off Sumba Island and five stations from the Gulf of Eilat in the Red Sea area were measured and interpreted within this dissertation. The main concern in gamma spectrometry of voluminous environmental samples is a reliable efficiency calibration. This is specially relevant for the analysis of low energy gamma emitters (<100 keV). 210 Pb, an important isotopic tracer to cover the period of the last century, is one of them. Within this work mathematical efficiency calibration was applied using a commercial software package. A series of validation tests was performed and evaluated for point and voluminous samples. When using 210 Pb as a tracer it is necessary to determine its excess portion, which is not supported by ingrowth from the parent nuclide 226 Ra. Its analysis is mostly performed via short lived daughter isotopes that follow after the intermediate gaseous member 222 Rn. Preventing the escape of radon from the sample is a critical step before analysis due to a negative effect of supported 210 Pb underestimation on the chronology, which was also documented in this thesis. Time series registering ingrowth of 214 Pb and 214 Bi towards radioactive equilibrium with 226 Ra in different containers were evaluated for analyses of 226 Ra. Direct analyses of 226 Ra was compared to its detection via daughter products. A method for aligning parallel radionuclide depth profiles was described and applied successfully in two case studies from the continental slope off NW Africa and off Sumba Island, Indonesia. This is primarily important when combined profiles obtained from short

  14. Gamma spectrometry for chronology of recent sediments

    Energy Technology Data Exchange (ETDEWEB)

    Pittauerova, Daniela

    2013-12-17

    This thesis deals with several aspects of gamma spectrometric analysis of natural and artificial isotopes in sediments and their use as tracers for qualification and quantification of accumulation and mixing processes in different aquatic environments. Sediment cores from three distinct areas including terrigenous sediments deposited on the continental slope off NW Africa, deep sea sediments off Sumba Island and five stations from the Gulf of Eilat in the Red Sea area were measured and interpreted within this dissertation. The main concern in gamma spectrometry of voluminous environmental samples is a reliable efficiency calibration. This is specially relevant for the analysis of low energy gamma emitters (<100 keV). {sup 210}Pb, an important isotopic tracer to cover the period of the last century, is one of them. Within this work mathematical efficiency calibration was applied using a commercial software package. A series of validation tests was performed and evaluated for point and voluminous samples. When using {sup 210}Pb as a tracer it is necessary to determine its excess portion, which is not supported by ingrowth from the parent nuclide {sup 226}Ra. Its analysis is mostly performed via short lived daughter isotopes that follow after the intermediate gaseous member {sup 222}Rn. Preventing the escape of radon from the sample is a critical step before analysis due to a negative effect of supported {sup 210}Pb underestimation on the chronology, which was also documented in this thesis. Time series registering ingrowth of {sup 214}Pb and {sup 214}Bi towards radioactive equilibrium with {sup 226}Ra in different containers were evaluated for analyses of {sup 226}Ra. Direct analyses of {sup 226}Ra was compared to its detection via daughter products. A method for aligning parallel radionuclide depth profiles was described and applied successfully in two case studies from the continental slope off NW Africa and off Sumba Island, Indonesia. This is primarily important

  15. Chronological development avenues in biotechnology across the world

    Directory of Open Access Journals (Sweden)

    Prashant Y Mali

    2011-01-01

    Full Text Available Biotechnology is expected to be a great technological revolution followed by information technology. It is an application of scientific and engineering principles to the processing of material by biological agents to provide better goods and services to mankind. Commercially its techniques are applied long back in 6 th century in the art of brewing, wine making and baking. It has progressed there after crossing different land marks. Modern biotechnology has developed significantly in the late 19 th century with groundbreaking discoveries applicable in medicine, food, agriculture, chemistry, environmental protection and many more industries. It is widely used in the development of high-yielding, disease-resistant, better quality varieties by applying tissue culture and recombinant DNA techniques. It has wide application in animal breeding using techniques such as artificial insemination, in vitro fertilization and embryo transfer. Specific enzymes used in laundry, fuel and leather industries for better quality, economically feasible and environmental friendly production. Biotechnology in healthcare system uses body′s own tools and weapons to fight against diseases, manufacturing of targeted therapeutic proteins, gene therapy and so on. Novel approaches such as proteomics and structural biology are contributing to understanding the chemistry of life and diseases. Malfunctioning gene replaced with correctly functioning gene by using gene therapy. Tissue engineering has opened up the use of in vitro developed tissue or organ in repairing wounded tissue and system biology which is a computer-based approach to understand cell functions. Although every new discovery related to biology and its implications is significant and has taken the technology ahead. This includes applications, commercialization, controversies, media exposure and so on. Hence, we have enlisted some of the chronological development avenues in biotechnology across the world.

  16. The History of Therapeutic Aerosols: A Chronological Review.

    Science.gov (United States)

    Stein, Stephen W; Thiel, Charles G

    2017-02-01

    In 1956, Riker Laboratories, Inc., (now 3 M Drug Delivery Systems) introduced the first pressurized metered dose inhaler (MDI). In many respects, the introduction of the MDI marked the beginning of the modern pharmaceutical aerosol industry. The MDI was the first truly portable and convenient inhaler that effectively delivered drug to the lung and quickly gained widespread acceptance. Since 1956, the pharmaceutical aerosol industry has experienced dramatic growth. The signing of the Montreal Protocol in 1987 led to a surge in innovation that resulted in the diversification of inhaler technologies with significantly enhanced delivery efficiency, including modern MDIs, dry powder inhalers, and nebulizer systems. The innovative inhalers and drugs discovered by the pharmaceutical aerosol industry, particularly since 1956, have improved the quality of life of literally hundreds of millions of people. Yet, the delivery of therapeutic aerosols has a surprisingly rich history dating back more than 3500 years to ancient Egypt. The delivery of atropine and related compounds has been a crucial inhalation therapy throughout this period and the delivery of associated structural analogs remains an important therapy today. Over the centuries, discoveries from many cultures have advanced the delivery of therapeutic aerosols. For thousands of years, therapeutic aerosols were prepared by the patient or a physician with direct oversight of the patient using custom-made delivery systems. However, starting with the Industrial Revolution, advancements in manufacturing resulted in the bulk production of therapeutic aerosol delivery systems produced by people completely disconnected from contact with the patient. This trend continued and accelerated in the 20th century with the mass commercialization of modern pharmaceutical inhaler products. In this article, we will provide a summary of therapeutic aerosol delivery from ancient times to the present along with a look to the future. We

  17. Signal Enhancement with Variable Span Linear Filters

    DEFF Research Database (Denmark)

    Benesty, Jacob; Christensen, Mads Græsbøll; Jensen, Jesper Rindom

    This book introduces readers to the novel concept of variable span speech enhancement filters, and demonstrates how it can be used for effective noise reduction in various ways. Further, the book provides the accompanying Matlab code, allowing readers to easily implement the main ideas discussed....... Variable span filters combine the ideas of optimal linear filters with those of subspace methods, as they involve the joint diagonalization of the correlation matrices of the desired signal and the noise. The book shows how some well-known filter designs, e.g. the minimum distortion, maximum signal......-to-noise ratio, Wiener, and tradeoff filters (including their new generalizations) can be obtained using the variable span filter framework. It then illustrates how the variable span filters can be applied in various contexts, namely in single-channel STFT-based enhancement, in multichannel enhancement in both...

  18. Signal enhancement with variable span linear filters

    CERN Document Server

    Benesty, Jacob; Jensen, Jesper R

    2016-01-01

    This book introduces readers to the novel concept of variable span speech enhancement filters, and demonstrates how it can be used for effective noise reduction in various ways. Further, the book provides the accompanying Matlab code, allowing readers to easily implement the main ideas discussed. Variable span filters combine the ideas of optimal linear filters with those of subspace methods, as they involve the joint diagonalization of the correlation matrices of the desired signal and the noise. The book shows how some well-known filter designs, e.g. the minimum distortion, maximum signal-to-noise ratio, Wiener, and tradeoff filters (including their new generalizations) can be obtained using the variable span filter framework. It then illustrates how the variable span filters can be applied in various contexts, namely in single-channel STFT-based enhancement, in multichannel enhancement in both the time and STFT domains, and, lastly, in time-domain binaural enhancement. In these contexts, the properties of ...

  19. A 481-year chronology of oak earlywood vessels as an age-independent climatic proxy in NW Iberia

    Science.gov (United States)

    Souto-Herrero, Manuel; Rozas, Vicente; García-González, Ignacio

    2017-08-01

    The earlywood vessels of ring-porous trees can be analyzed dendrochronologically and used as a proxy for environmental information. However, most works deal with the analysis of contemporary climate-growth relationships and do not evaluate their long-term variation. We obtained a 481-year chronology of earlywood vessel size of oak (Quercus robur L.) in the northwestern Iberian Peninsula, investigated its behavior through time, and compared it to a chronology of younger trees developed at the same site. We expressed earlywood vessel size as the hydraulically-weighted diameter (DH) and discriminated between vessels in the first row (r1) and the rest of the vessels (nr1); radial increment was assessed from latewood width (LW). Climate-growth relationships were strong and nearly identical for both age classes. Spring temperature positively affected vessel size, but only for the first row, probably mediating the onset of cambial activity. The chronology of old trees showed an almost flat age trend, except for the first decades, and series were not affected by stand dynamics. In contrast, LW had a weak response to climate, probably because of the high impact of abrupt growth changes. There was a high negative correlation between DH and the winter North Atlantic Oscillation Index (NAO), which was unstable during the 20th century. To our knowledge, this is the longest chronology of earlywood vessel size obtained to date, and offers promising results, as this proxy is shown to be independent of age and forest disturbances, and was strongly correlated to climate across long time spans.

  20. Ancient Egyptian chronology and the astronomical orientation of pyramids

    Science.gov (United States)

    Spence, Kate

    2000-11-01

    The ancient Egyptian pyramids at Giza have never been accurately dated, although we know that they were built approximately around the middle of the third millennium BC. The chronologies of this period have been reconstructed from surviving lists of kings and the lengths of their reigns, but the lists are rare, seldom complete and contain known inconsistencies and errors. As a result, the existing chronologies for that period (the Old Kingdom) can be considered accurate only to about +/-100 years, a figure that radiocarbon dating cannot at present improve. Here I use trends in the orientation of Old Kingdom pyramids to demonstrate that the Egyptians aligned them to north by using the simultaneous transit of two circumpolar stars. Modelling the precession of these stars yields a date for the start of construction of the Great Pyramid that is accurate to +/-5 yr, thereby providing an anchor for the Old Kingdom chronologies.

  1. Linking crowding, visual span, and reading.

    Science.gov (United States)

    He, Yingchen; Legge, Gordon E

    2017-09-01

    The visual span is hypothesized to be a sensory bottleneck on reading speed with crowding thought to be the major sensory factor limiting the size of the visual span. This proposed linkage between crowding, visual span, and reading speed is challenged by the finding that training to read crowded letters reduced crowding but did not improve reading speed (Chung, 2007). Here, we examined two properties of letter-recognition training that may influence the transfer to improved reading: the spatial arrangement of training stimuli and the presence of flankers. Three groups of nine young adults were trained with different configurations of letter stimuli at 10° in the lower visual field: a flanked-local group (flanked letters localized at one position), a flanked-distributed group (flanked letters distributed across different horizontal locations), and an isolated-distributed group (isolated and distributed letters). We found that distributed training, but not the presence of flankers, appears to be necessary for the training benefit to transfer to increased reading speed. Localized training may have biased attention to one specific, small area in the visual field, thereby failing to improve reading. We conclude that the visual span represents a sensory bottleneck on reading, but there may also be an attentional bottleneck. Reducing the impact of crowding can enlarge the visual span and can potentially facilitate reading, but not when adverse attentional bias is present. Our results clarify the association between crowding, visual span, and reading.

  2. London SPAN version 4 parameter file format

    International Nuclear Information System (INIS)

    2004-06-01

    Powernext SA is a Multilateral Trading Facility in charge of managing the French power exchange through an optional and anonymous organised trading system. Powernext SA collaborates with the clearing organization LCH.Clearnet SA to secure and facilitate the transactions. The French Standard Portfolio Analysis of Risk (SPAN) is a system used by LCH.Clearnet to calculate the initial margins from and for its clearing members. SPAN is a computerized system which calculates the impact of several possible variations of rates and volatility on by-product portfolios. The initial margin call is equal to the maximum probable loss calculated by the system. This document contains details of the format of the London SPAN version 4 parameter file. This file contains all the parameters and risk arrays required to calculate SPAN margins. London SPAN Version 4 is an upgrade from Version 3, which is also known as LME SPAN. This document contains the full revised file specification, highlighting the changes from Version 3 to Version 4

  3. Concerning the chronology of Cimabue's oeuvre and the origin of pictorial depth in Italian painting of the later middle ages

    Directory of Open Access Journals (Sweden)

    Polzer Joseph

    2002-01-01

    Full Text Available A study devoted to the gradual emergence of pictorial depth in Cimabue's paintings, and how it applies, together with other factors, to the understanding of their sequential chronology. The conclusions reached underscore the vast difference in Cimabue 's conservative art and the exceptional naturalism of the evolving Life of Saint Francis mural cycle lining the lower nave walls in the upper church of San Francesco at Assisi.

  4. Changing the narrative – Life span perspectives on multiple adversity

    OpenAIRE

    Bunting, Lisa; Lazenbatt, Anne

    2016-01-01

    Although the impact of multiple adverse events in childhood is well known, it is equally accepted that the variation in individual trajectories and outcomes is significant. Resilience focuses on positive adaption in the face of adversity, offering a counterbalance to deficit-based research and risk averse, procedurally driven practice. Positive relationships and secure attachments are widely considered to be the cornerstone of resilience, yet, within social work practice, there is a tendency ...

  5. A cultural perspective on emotional experiences across the life span.

    Science.gov (United States)

    Grossmann, Igor; Karasawa, Mayumi; Kan, Chiemi; Kitayama, Shinobu

    2014-08-01

    Past research suggests that older adults place a greater priority on goals of maintaining positive experiences and distancing from negative experiences. We hypothesized that these aging-related differences in emotional experiences are more pronounced in Western cultures that encourage linear approaches to well-being compared with Eastern cultures that encourage more dialectic approaches to well-being. We compared reports of positive and negative emotional experiences from random samples of Americans (a culture characterized by focus on positive and distancing from negative experiences) and Japanese (a culture characterized by its endorsement of dialectical experiences). In support of our hypothesis, older Americans reported significantly less negative emotions in unpleasant situations, relative to their younger counterparts. Furthermore, both trait-level negativity (i.e., rumination) and interpersonal negativity (i.e., recall of unpleasant relationships and intensity of an unpleasant interpersonal experience) were lower among older compared with younger Americans. In contrast, such aging-related effects were absent in the Japanese respondents. Even though older and younger Japanese reported the same amount of negative emotions in unpleasant situations, older Japanese also reported more positive emotions in the same unpleasant situations. Together, these findings highlight the role of culture for understanding how emotional experiences unfold across adulthood.

  6. Inconsistency in reaction time across the life span.

    Science.gov (United States)

    Williams, Benjamin R; Hultsch, David F; Strauss, Esther H; Hunter, Michael A; Tannock, Rosemary

    2005-01-01

    Inconsistency in latency across trials of 2-choice reaction time data was analyzed in 273 participants ranging in age from 6 to 81 years. A U-shaped curve defined the relationship between age and inconsistency, with increases in age associated with lower inconsistency throughout childhood and higher inconsistency throughout adulthood. Differences in inconsistency were independent of practice, fatigue, and age-related differences in mean level of performance. Evidence for general and specific variability-producing processes was found in those aged less than 21 years, whereas only a specific process, such as attentional blocks, was evident for those 21 years and older. The findings highlight the importance of considering moment-to-moment changes in performance in psychological research. 2005 APA

  7. Online dating across the life span: Users' relationship goals.

    Science.gov (United States)

    Menkin, Josephine A; Robles, Theodore F; Wiley, Joshua F; Gonzaga, Gian C

    2015-12-01

    Utilizing data from an eHarmony.com relationship questionnaire completed by new users (N = 5,434), this study identifies prioritized goals in new romantic relationships and whether importance of these goals differs by participants' age and gender. Overall, users valued interpersonal communication more than sex appeal. Older users rated sexual attraction as slightly less important than younger users did, but they still highly valued the goal. Women placed even greater emphasis on communication over sexual attraction compared to men. However, although men valued sexual attraction more than women at all ages, only the youngest women valued interpersonal communication more than young men. (c) 2015 APA, all rights reserved).

  8. Predicting nature-based tourist roles: a life span perspective

    Science.gov (United States)

    James J. Murdy; Heather J. Gibson; Andrew Yiannakis

    2003-01-01

    The concept of stable, clearly identifiable patterns of tourist behavior, or roles, is a relatively recent development. Yiannakis and Gibson (1988, 1992) identified fifteen tourist roles based on leisure travelers' vacation behaviors. Building on this work, Gibson (1994) used discriminant analysis to determine the combination of needs and demographics are...

  9. A Hierarchical Causal Taxonomy of Psychopathology across the Life Span

    Science.gov (United States)

    Lahey, Benjamin B.; Krueger, Robert F.; Rathouz, Paul J.; Waldman, Irwin D.; Zald, David H.

    2016-01-01

    We propose a taxonomy of psychopathology based on patterns of shared causal influences identified in a review of multivariate behavior genetic studies that distinguish genetic and environmental influences that are either common to multiple dimensions of psychopathology or unique to each dimension. At the phenotypic level, first-order dimensions are defined by correlations among symptoms; correlations among first-order dimensions similarly define higher-order domains (e.g., internalizing or externalizing psychopathology). We hypothesize that the robust phenotypic correlations among first-order dimensions reflect a hierarchy of increasingly specific etiologic influences. Some nonspecific etiologic factors increase risk for all first-order dimensions of psychopathology to varying degrees through a general factor of psychopathology. Other nonspecific etiologic factors increase risk only for all first-order dimensions within a more specific higher-order domain. Furthermore, each first-order dimension has its own unique causal influences. Genetic and environmental influences common to family members tend to be nonspecific, whereas environmental influences unique to each individual are more dimension-specific. We posit that these causal influences on psychopathology are moderated by sex and developmental processes. This causal taxonomy also provides a novel framework for understanding the heterogeneity of each first-order dimension: Different persons exhibiting similar symptoms may be influenced by different combinations of etiologic influences from each of the three levels of the etiologic hierarchy. Furthermore, we relate the proposed causal taxonomy to transdimensional psychobiological processes, which also impact the heterogeneity of each psychopathology dimension. This causal taxonomy implies the need for changes in strategies for studying the etiology, psychobiology, prevention, and treatment of psychopathology. PMID:28004947

  10. Human Needs: A Literature Review and Cognitive Life Span Model

    Science.gov (United States)

    1992-04-01

    stages where crises are met, and, if favorably resolved, result in personality growth. Erikson’s psychosocial theory covers development from birth to...death. He describes eight major tasks or challenges people face as they undergo psychosocial development . Three of the eight stages of development ...the order that Erikson suggested. Several researchers (e.g., Rosenthal, Gurney, & Moore, 1981) have developed inventories that measure Erikson’s stages

  11. Nitrogen availability, leaf life span and nitrogen conservation mechanisms in leaves of tropical trees Disponibilidade de nitrogênio, longevidade foliar e mecanismos de conservação de nitrogênio em folhas de espécies arbóreas tropicais

    Directory of Open Access Journals (Sweden)

    Guilherme Nascimento Corte

    2009-12-01

    Full Text Available Evergreen species of temperate regions are dominant in low-nutrient soils. This feature is attributed to more efficient mechanisms of nutrient economy. Nevertheless, the cashew (Anacardium occidentale- Anacardiaceae, a deciduous species, is native to regions in Brazil with sandy soil, whilst the annatto (Bixa orellana- Bixaceae, classified as an evergreen species native to tropical America, grows spontaneously in regions with more humid soils. Evergreens contain robust leaves that can resist adverse conditions for longer. The physical aspects of the leaves and mechanisms of nutrient economy between the two species were compared, in order to verify whether the deciduous species had more efficient mechanisms that might explain its occurrence in regions of low soil fertility. The mechanisms of nitrogen economy were also compared for the two species at available concentrations of this nutrient. The following were analysed: (i leaf life span, (ii physical leaf characteristics (leaf mass per area, and rupture strain, (iii nitrogenous compounds (nitrogen, chlorophyll, and protein, (iv nitrogen conservation mechanisms (nitrogen resorption efficiency, resorption proficiency, and use efficiency, and (v nitrogen conservation mechanisms under different availability of this mineral. The higher values of leaf mass per area and leaf rupture strain found in A. occidentale were related to its longer leaf life span. A. occidentale showed lower concentrations of nitrogen and protein in the leaves than B. orellana. Under lower nitrogen availability, A. occidentale had higher nitrogen resorption proficiency, nitrogen use efficiency and leaf life span than B. orellana. These characteristics may contribute to the adaptation of this species to sandy soils with low nitrogen content.Perenifólias de clima temperado são dominantes em solos pouco férteis. Essa característica é atribuída a mecanismos mais eficientes de economia de nutrientes. O cajueiro (Anacardium

  12. Astronautics and aeronautics, 1972. [a chronology of events

    Science.gov (United States)

    1974-01-01

    Important events of the U. S. space program during 1972 are recorded in a chronology which encompasses all NASA, NASA related, and international cooperative efforts in aeronautics and astronautics. Personnel and budget concerns are documented, along with the major developments in aircraft research, manned space flight, and interplanetary exploration.

  13. Chronology of p53 protein accumulation in gastric carcinogenesis

    NARCIS (Netherlands)

    Craanen, M. E.; Blok, P.; Dekker, W.; Offerhaus, G. J.; Tytgat, G. N.

    1995-01-01

    p53 Protein accumulation in early gastric carcinoma was studied in relation to the histological type (Lauren classification) and the type of growth pattern, including the chronology of p53 protein accumulation during carcinogenesis. Forty five, paraffin embedded gastrectomy specimens from early

  14. Performance, Career Dynamics, and Span of Control

    DEFF Research Database (Denmark)

    Smeets, Valerie Anne Rolande; Waldman, Michael; Warzynski, Frederic Michel Patrick

    that higher ability managers should supervise more subordinates, or equivalently, have a larger span of control. And although some of this theory’s predictions have been empirically investigated, there has been little systematic investigation of the theory’s predictions concerning span of control....... In this paper we first extend the theoretical literature on the scale-of-operations effect to allow firms’ beliefs concerning a manager’s ability to evolve over the manager’s career, where much of our focus is the determinants of span of control. We then empirically investigate testable predictions from......There is an extensive theoretical literature based on what is called the scale-of-operations effect, i.e., the idea that the return to managerial ability is higher the more resources the manager influences with his or her decisions. This idea leads to various testable predictions including...

  15. Evaluating the efficiency of shortcut span protection

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Dittmann, Lars; Berger, Michael Stübert

    2010-01-01

    This paper presents a comparison of various recovery methods in terms of capacity efficiency with the underlying aim of reducing control plane load. In particular, a method where recovery requests are bundled towards the destination (Shortcut Span Protection) is evaluated can compared against tra...... traditional recovery methods. The optimization model is presented and our simulation results show that Shortcut Span Protection uses more capacity than the unbundled related methods, but this is compensated by easier control and management of the recovery actions.......This paper presents a comparison of various recovery methods in terms of capacity efficiency with the underlying aim of reducing control plane load. In particular, a method where recovery requests are bundled towards the destination (Shortcut Span Protection) is evaluated can compared against...

  16. Van Kampen Colimits as Bicolimits in Span

    Science.gov (United States)

    Heindel, Tobias; Sobociński, Paweł

    The exactness properties of coproducts in extensive categories and pushouts along monos in adhesive categories have found various applications in theoretical computer science, e.g. in program semantics, data type theory and rewriting. We show that these properties can be understood as a single universal property in the associated bicategory of spans. To this end, we first provide a general notion of Van Kampen cocone that specialises to the above colimits. The main result states that Van Kampen cocones can be characterised as exactly those diagrams in ℂ that induce bicolimit diagrams in the bicategory of spans mathcal{S}pan_{mathbb{C}}, provided that ℂ has pullbacks and enough colimits.

  17. Spanning organizational boundaries to manage creative processes:

    DEFF Research Database (Denmark)

    Andersen, Poul Houman; Kragh, Hanne; Lettl, Christopher

    2013-01-01

    In order to continue to be innovative in the current fast-paced and competitive environment, organizations are increasingly dependent on creative inputs developed outside their boundaries. The paper addresses the boundary spanning activities that managers undertake to a) select and mobilize...... creative talent, b) create shared identity, and c) combine and integrate knowledge in innovation projects involving external actors. We study boundary spanning activities in two creative projects in the LEGO group. One involves identifying and integrating deep, specialized knowledge, the other focuses...... actors, and how knowledge is integrated across organizational boundaries. We discuss implications of our findings for managers and researchers in a business-to-business context...

  18. Spanning the Home/Work Creative Space

    DEFF Research Database (Denmark)

    Davis, Lee N.; Davis, Jerome; Hoisl, Karin

    the employee brings to work. Based on Woodman et al.’s (1993) “interactionist perspective” on organizational creativity, supplemented by literature on search and knowledge re/combination, we explore whether and how leisure time activities can span the creative space between the employee’s home and workplace...

  19. Faster Fully-Dynamic minimum spanning forest

    DEFF Research Database (Denmark)

    Holm, Jacob; Rotenberg, Eva; Wulff-Nilsen, Christian

    2015-01-01

    We give a new data structure for the fully-dynamic minimum spanning forest problem in simple graphs. Edge updates are supported in O(log4 n/log logn) expected amortized time per operation, improving the O(log4 n) amortized bound of Holm et al. (STOC’98, JACM’01).We also provide a deterministic data...

  20. Energy history chronology from World War II to the present

    Energy Technology Data Exchange (ETDEWEB)

    Dean, P.C.

    1982-08-01

    This report provides a basic guide to the major Presidential, Legislative, Judicial, and Federal agency actions relating to energy policy, research, development, and regulation in recent years. The chronology is arranged synoptically, allowing users to reference easily the historical context in which each event occurred. Summaries of Presidential, Legislative, and Judicial actions relating to energy, rosters of federal energy officials, and a genealogy of federal energy agencies are also provided in separate appendices. The Energy History Chronology was prepared in conjunction with the History Division's series of pamphlets on the Institutional Origins of the Department of Energy. The series includes concise histories of the Department of Energy, the Energy Research and Development Administration, the Federal Energy Administration, and the Atomic Energy Commission. All significant events and achievements noted in the institutional history are also listed.

  1. Chronology and development of the Chalcolithic necropolis of Varna I

    Directory of Open Access Journals (Sweden)

    Raiko Krauß

    2018-01-01

    Full Text Available In the following paper, we present the main results of our now completed studies of the Varna I cemetery, based on the excavations undertaken by Ivan Ivanov in the years 1972–1991. The richness of the assemblages is singular in Old World prehistory. To tackle the question of its inter­nal, chronological development, we applied correspondence analysis (CA to a newly created database that includes the inventories of all presently known graves, symbolic burials and find de­posits. The rank order of the seriated inventories was used to establish a CA-based 14C-age model for wiggle matching. In combination with topographic observations and social network analysis (SNA, our studies provide a new understanding both of the chronological and spatial distribution of the graves and burial goods, as well as new insights into the social structure, gender roles, individual relation­ships and ritual practices of the Chalcolithic community.

  2. Insight into the Fulnek Church and Parish Medieval Building Chronology

    Directory of Open Access Journals (Sweden)

    Augustinková Lucie

    2017-06-01

    Full Text Available The church of the Holy Trinity and parish in Fulnek was for nearly four centuries an Augustinian canonry and collegiate church (1293-1389. The medieval church and parish building chronology, however, have not been thus far established. From research between 2015 and 2016 we have been able to identify medieval portions of the buildings, clarify the site medieval construction phases and date the parish buildings (formerly the canonry from dendrochronological analysis of embedded wooden scaffolding.

  3. Constructing deposition chronologies for peat deposits using radiocarbon dating

    Directory of Open Access Journals (Sweden)

    N. Piotrowska

    2011-06-01

    Full Text Available Radiocarbon dating is one of the main methods used to establish peat chronologies. This article reviews the basis of the method and its application to dating of peat deposits. Important steps in the radiocarbon dating procedure are described, including selection and extraction of material (and fractions for dating, chemical and physical preparation of media suitable for measurements, measurements of 14C activity or concentration, calculations, calibration of results and age-depth modelling.

  4. The Creation of the world and the birth of chronology

    Science.gov (United States)

    Richet, Pascal

    2017-09-01

    The eternity of the world and, correlatively, the cyclical nature of time were agreed upon by all Greek philosophical schools except the Platonists. As for matter, all of them posited that it was eternal so that the idea that something could be made from nothing was considered as pure absurdity. With the advent of Christianity, however, a matter coeternal with God raised fundamental theological difficulties. Toward the end of the second century, apologists such as Tatian the Assyrian, Theophilus of Antioch, Irenaeus of Lyons or Tertullian thus emphasized God's absolute freedom and power by claiming that Creation had been made from nothing. Along with the Passion of Christ and the Last Judgment, the initial moment defined by the Creation then conferred to time an irreversible, linear orientation and to history both a new sense and an obsessing concern for chronology. Unambiguously, the Creation became the reference point for the world's history. From Scripture analyses, one determined that it took place about 5500 years earlier within a framework where the History of man and that of the earth were not distinct. Having designed a consistent, universal time scale from chronological data recorded for all ancient peoples, Eusebius of Caesarea could thus attribute to the Great Flood the fossils found on the top of Mount Lebanon. The short Mosaic chronologies were eventually rejected during the 18th century, but Eusebius' chronological procedure was unknowingly transposed when a relative geological timescale was then set up from the fossil record. The close association of Creation with Christian dogma in turn induced some circles to reject the second law of thermodynamics at the end of the 19th century and, a few decades later, the thesis of an expanding universe. In both cases, the reason was that continuously increasing entropy would imply some low-entropy initial state akin to a Creation.

  5. Events of radioactive waste management - a chronological table

    International Nuclear Information System (INIS)

    1985-01-01

    In chronological order the leaflet abstracted points out the essential data of German radioactive waste management. The data reach from December 1951 with EBR I (Idaho/USA) being the first one to feed electric power to the distribution grid to February 1985 known as the date of the submission of building applications for the first partial license of the Wackersdorf reprocessing plant. (HSCH) [de

  6. The use of AMS radiocarbon dating for Xia-Shang-Zhou chronology

    CERN Document Server

    Guo, Z Y; LiuKeXin; Lu Xiang Yang; Ma Hong Ji; Wu Xiao Hon; Yuan Si Xun

    2000-01-01

    The possibility and problems of using radiocarbon dating to historical chronology are discussed. The current situation of ancient Chinese chronology and the project of Xia-Shang-Zhou chronology are introduced. A chronological study requires the AMS radiocarbon dating with high precision, high reliability and high efficiency. The Peking University AMS facility (PKUAMS) has been upgraded and a series of quality control steps were adopted. To reduce the error of calendar age, wiggle matching with serial samples should be used. Some preliminary results of Xia-Shang-Zhou chronology are presented.

  7. MANUTENÇÃO DE FOLHAS ATIVAS EM BANANEIRA-'NANICÃO' POR MEIO DO MANEJO DAS ADUBAÇÕES NITROGENADA E POTÁSSICA E DA IRRIGAÇÃO IMPROVING LIFE SPAN OF THE BANANA LEAVES THROUGH NITROGEN AND POTASSIUM FERTILIZATION AND IRRIGATION

    Directory of Open Access Journals (Sweden)

    LUIZ ANTONIO JUNQUEIRA TEIXEIRA

    2001-12-01

    Full Text Available Realizou-se um experimento de campo, em Jaboticabal-SP, com o objetivo de estudar a resposta da bananeira (Musa AAA subgrupo Cavendish-'Nanicão' à adubação nitrogenada e potássica, sob irrigação e sequeiro, durante duas safras. Empregou-se o delineamento experimental de blocos ao acaso, com os tratamentos em parcelas subdivididas, sendo as parcelas principais constituídas por dois regimes hídricos: irrigado (microaspersão e sequeiro, e as subparcelas, pelas combinações de quatro doses de N (0; 200; 400 e 800 kg ha-1de N e quatro de K (0; 300; 600 e 900 kg ha-1de K2O. O bananal foi cultivado de acordo com as recomendações atuais, tomando-se cuidados especiais com o controle preventivo de sigatoca-amarela e com o manejo da irrigação. Por meio da análise do número de folhas ativas (>50% da área verde nas épocas da emissão da inflorescência (NFE e da colheita (NFC, do índice de durabilidade foliar (IDF=NFC¸NFE´100 e dos teores de N e K na folha-índice, avaliaram-se os efeitos da irrigação e da aplicação de doses crescentes de N e K sobre as condições das folhas. Nos dois ciclos de cultivo, houve efeito da adubação potássica e da irrigação sobre o estado das folhas (pA field experiment was carried out in São Paulo State, Brazil, with the objective of investigating the response of 'Nanicão' banana (Musa AAA Cavendish subgroup to nitrogen and potassium fertilization, under irrigated and non-irrigated conditions, during two crop seasons. A split-plot design was used with irrigation (micro-sprinkler and no irrigation applied to main plots and a combination of four rates of N (0, 200, 400 and 800 kg N ha-1 and K (0, 300, 600 and 900 kg K2O ha-1 as the sub-plots treatments. The area was managed according to regional recommendations; special attention was paid to disease control and irrigation management. The effects of treatments on life span of leaves were assessed counting leaves at flowering (NFE and at bunch

  8. Minimal spanning trees, filaments and galaxy clustering

    International Nuclear Information System (INIS)

    Barrow, J.D.; Sonoda, D.H.

    1985-01-01

    A graph theoretical technique for assessing intrinsic patterns in point data sets is described. A unique construction, the minimal spanning tree, can be associated with any point data set given all the inter-point separations. This construction enables the skeletal pattern of galaxy clustering to be singled out in quantitative fashion and differs from other statistics applied to these data sets. This technique is described and applied to two- and three-dimensional distributions of galaxies and also to comparable random samples and numerical simulations. The observed CfA and Zwicky data exhibit characteristic distributions of edge-lengths in their minimal spanning trees which are distinct from those found in random samples. (author)

  9. Interorganizational Boundary Spanning in Global Software Development

    DEFF Research Database (Denmark)

    Søderberg, Anne-Marie; Romani, Laurence

    , and which skills and competencies they draw on in their efforts to deal with emerging cross-cultural issues in a way that paves ground for developing a shared understanding and common platform for the client and vendor representatives. A framework of boundary spanning leadership practices is adapted...... to virtuality and cultural diversity. This paper, which draws on a case study of collaborative work in a global software development project, focuses on key boundary spanners in an Indian vendor company, who are responsible for developing trustful and sustainable client relations and coordinating complex...... projects across multiple cultures, languages, organisational boundaries, time zones and geographical distances. It looks into how these vendor managers get prepared for their complex boundary spanning work, which cross-cultural challenges they experience in their collaboration with Western clients...

  10. Spanning trees and the Eurozone crisis

    Science.gov (United States)

    Dias, João

    2013-12-01

    The sovereign debt crisis in the euro area has not yet been solved and recent developments in Spain and Italy have further deteriorated the situation. In this paper we develop a new approach to analyze the ongoing Eurozone crisis. Firstly, we use Maximum Spanning Trees to analyze the topological properties of government bond rates’ dynamics. Secondly, we combine the information given by both Maximum and Minimum Spanning Trees to obtain a measure of market dissimilarity or disintegration. Thirdly, we extend this measure to include a convenient distance not limited to the interval [0, 2]. Our empirical results show that Maximum Spanning Tree gives an adequate description of the separation of the euro area into two distinct groups: those countries strongly affected by the crisis and those that have remained resilient during this period. The measures of market dissimilarity also reveal a persistent separation of these two groups and, according to our second measure, this separation strongly increased during the period July 2009-March 2012.

  11. Vision in Flies: Measuring the Attention Span.

    Science.gov (United States)

    Koenig, Sebastian; Wolf, Reinhard; Heisenberg, Martin

    2016-01-01

    A visual stimulus at a particular location of the visual field may elicit a behavior while at the same time equally salient stimuli in other parts do not. This property of visual systems is known as selective visual attention (SVA). The animal is said to have a focus of attention (FoA) which it has shifted to a particular location. Visual attention normally involves an attention span at the location to which the FoA has been shifted. Here the attention span is measured in Drosophila. The fly is tethered and hence has its eyes fixed in space. It can shift its FoA internally. This shift is revealed using two simultaneous test stimuli with characteristic responses at their particular locations. In tethered flight a wild type fly keeps its FoA at a certain location for up to 4s. Flies with a mutation in the radish gene, that has been suggested to be involved in attention-like mechanisms, display a reduced attention span of only 1s.

  12. Vision in Flies: Measuring the Attention Span.

    Directory of Open Access Journals (Sweden)

    Sebastian Koenig

    Full Text Available A visual stimulus at a particular location of the visual field may elicit a behavior while at the same time equally salient stimuli in other parts do not. This property of visual systems is known as selective visual attention (SVA. The animal is said to have a focus of attention (FoA which it has shifted to a particular location. Visual attention normally involves an attention span at the location to which the FoA has been shifted. Here the attention span is measured in Drosophila. The fly is tethered and hence has its eyes fixed in space. It can shift its FoA internally. This shift is revealed using two simultaneous test stimuli with characteristic responses at their particular locations. In tethered flight a wild type fly keeps its FoA at a certain location for up to 4s. Flies with a mutation in the radish gene, that has been suggested to be involved in attention-like mechanisms, display a reduced attention span of only 1s.

  13. Effect of high dose irradiation on the red cell span in rabbits

    International Nuclear Information System (INIS)

    Kang, T.W.; Koh, J.W.; Woo, K.S.; Lee, O.H.; Youn, C.S.

    1982-01-01

    As a part of studies on acute effects of high dose irradiation in vivo, the present report was carried out to evaluate the changes of the red cell life span in the white rabbits by a single whole body exposure to gamma rays from 60 Co teletherapy unit. The exposure was done in dose levels of 100, 600 and 900 rads to each experimental group of 10 rabbits. The life span apparent half survival time of red cells, and that the red cell volume in the circulting blood were measured by ICSH Reference method using 51 Cr. (Author)

  14. Middle and Later Stone Age chronology of Kisese II rockshelter (UNESCO World Heritage Kondoa Rock-Art Sites), Tanzania

    Science.gov (United States)

    Ranhorn, Kathryn L.; Kwekason, Amandus; Alex, Bridget; Laird, Myra F.; Marean, Curtis W.; Niespolo, Elizabeth; Nivens, Joelle; Mabulla, Audax Z. P.

    2018-01-01

    The archaeology of East Africa during the last ~65,000 years plays a central role in debates about the origins and dispersal of modern humans, Homo sapiens. Despite the historical importance of the region to these discussions, reliable chronologies for the nature, tempo, and timing of human behavioral changes seen among Middle Stone Age (MSA) and Later Stone Age (LSA) archaeological assemblages are sparse. The Kisese II rockshelter in the Kondoa region of Tanzania, originally excavated in 1956, preserves a ≥ 6-m-thick archaeological succession that spans the MSA/LSA transition, with lithic artifacts such as Levallois and bladelet cores and backed microliths, the recurrent use of red ochre, and >5,000 ostrich eggshell beads and bead fragments. Twenty-nine radiocarbon dates on ostrich eggshell carbonate make Kisese II one of the most robust chronological sequences for understanding archaeological change over the last ~47,000 years in East Africa. In particular, ostrich eggshell beads and backed microliths appear by 46–42 ka cal BP and occur throughout overlying Late Pleistocene and Holocene strata. Changes in lithic technology suggest an MSA/LSA transition that began 39–34.3 ka, with typical LSA technologies in place by the Last Glacial Maximum. The timing of these changes demonstrates the time-transgressive nature of behavioral innovations often linked to the origins of modern humans, even within a single region of Africa. PMID:29489827

  15. Middle and Later Stone Age chronology of Kisese II rockshelter (UNESCO World Heritage Kondoa Rock-Art Sites), Tanzania.

    Science.gov (United States)

    Tryon, Christian A; Lewis, Jason E; Ranhorn, Kathryn L; Kwekason, Amandus; Alex, Bridget; Laird, Myra F; Marean, Curtis W; Niespolo, Elizabeth; Nivens, Joelle; Mabulla, Audax Z P

    2018-01-01

    The archaeology of East Africa during the last ~65,000 years plays a central role in debates about the origins and dispersal of modern humans, Homo sapiens. Despite the historical importance of the region to these discussions, reliable chronologies for the nature, tempo, and timing of human behavioral changes seen among Middle Stone Age (MSA) and Later Stone Age (LSA) archaeological assemblages are sparse. The Kisese II rockshelter in the Kondoa region of Tanzania, originally excavated in 1956, preserves a ≥ 6-m-thick archaeological succession that spans the MSA/LSA transition, with lithic artifacts such as Levallois and bladelet cores and backed microliths, the recurrent use of red ochre, and >5,000 ostrich eggshell beads and bead fragments. Twenty-nine radiocarbon dates on ostrich eggshell carbonate make Kisese II one of the most robust chronological sequences for understanding archaeological change over the last ~47,000 years in East Africa. In particular, ostrich eggshell beads and backed microliths appear by 46-42 ka cal BP and occur throughout overlying Late Pleistocene and Holocene strata. Changes in lithic technology suggest an MSA/LSA transition that began 39-34.3 ka, with typical LSA technologies in place by the Last Glacial Maximum. The timing of these changes demonstrates the time-transgressive nature of behavioral innovations often linked to the origins of modern humans, even within a single region of Africa.

  16. Documentary-derived chronologies of rainfall variability in Antigua, Lesser Antilles, 1770–1890

    Directory of Open Access Journals (Sweden)

    A. J. Berland

    2013-06-01

    Full Text Available This paper presents the first extensive reconstruction of precipitation variability in the Lesser Antilles using historical documentary sources. Over 13 250 items of documentation pertaining to Antigua from the period 1769–1890 were consulted, including missionary, plantation and governmental papers as well as contemporary scholarly publications. Based on the predominant meteorological conditions observed throughout the island, each "rain-year" (December–November was assigned one of five classifications (very wet, wet, "normal", dry and very dry. Local weather references relating to seven plantations in central-eastern Antigua were grouped according to dry (December–April and wet seasons (May–November, each of which were also categorised in the aforementioned manner. Results comprise individual island-wide and central-eastern Antiguan chronologies of relative precipitation levels, spanning the rain-years 1769–70 to 1889–90 and 1769–70 to 1853–54 respectively. The former is compared with available instrumental data for the years 1870–1890. Significant dry phases are identified in the rain-years 1775–80, 1788–91, 1820–22, 1834–37, 1844–45, 1859–60, 1862–64, 1870–74 and 1881–82, while wet episodes were 1771–74, 1833–34, 1837–38, 1841–44, 1845–46 and 1878–81. Evidence for major wet and dry spells is presented and findings are evaluated within wider historical and palaeoclimatic contexts.

  17. K-Ar chronological study of the quaternary volcanic activity in Shin-etsu Highland

    International Nuclear Information System (INIS)

    Kaneko, Takayuki; Shimizu, Satoshi; Itaya, Tetsumaru.

    1989-01-01

    In order to clarify the temporal and spatial patterns in arc volcanism, 55 K-Ar ages of volcanic rocks from 17 volcanoes in Shin-etsu Highland, central Japan were determined. In addition, life spans, volume of erupted materials and eruption rates of each volcano were estimated. Graphical analysis demonstrates that volume of ejecta varies proportionately with both life span and eruption rate, and that there is no significant correlation between eruption rate and distance from the volcanic front. The life span of each volcano in this Highland is less than 0.6 m.y. In the central Shiga and southern Asama area, the volcanism started at 1 Ma and is still active. However the former had a peak in the activity at around 0.5 Ma, while the latter is apparently most intense at present. Northern Kenashi area has the volcanism without peak in 1.7 - 0.2 Ma, though the activity within a volcanic cluster or chain in central Japan lasts generally for 1 m.y. or less with a peak. (author)

  18. Age spans of some Indian speleothems

    International Nuclear Information System (INIS)

    Yadava, M.G.; Ramesh, R.; Polyak, V.J.; Asmerom, Y.

    2009-01-01

    In recent years, research on speleothems (minerals growing in caves, i.e. stalactites, stalagmites and flowstones) have shown that these have potential to provide records of past climate and environmental changes. Speleothems have several advantages compared to other high-resolution land archives (e.g., tree rings and lake sediments). Firstly, these are unaffected by natural erosion processes yielding long records of climate variability. Secondly, precise chronology by U-Th mass spectrometry is possible now. Prior to the advent of mass spectrometry (late 1980s), radiocarbon decay method was applied to date young samples (<40 kyr) and U-Th-alpha-counting method was adopted for older samples. In comparison with radiocarbon dates uranium series dates are absolute ages and no calibration is required. In India, palaeoclimate research using speleothem is in infancy, some work has been reported from Himalaya, central India and Peninsular India, with oxygen isotopes being used as monsoon proxy. Five speleothems from four Indian caves have been dated by U- Th method to estimate their ages and growth durations. Results indicate that these grew during various time intervals in Holocene and late Pleistocene

  19. Free span burial inspection pig. Phase B

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-04-01

    This report deals with design and construction of a pipeline pig for on-line internal inspection of offshore trenched gas pipelines for pipeline burial, free spans, exposures and loss of concrete weight coating. The measuring principle uses detection of the natural gamma radiation emitted by sea bed formations and the concrete coating of the pipe to map pipeline condition. The gamma ray flux penetrating to the internal side of the pipeline is an effect of the outside conditions. The measuring principle was confirmed in a occasionally present in the gas, blurred seriously sensor signals of the previous instrumentation. The continued project activities have been divided in two phases. Phase A comprised design and construction of a detector system, which could identify and quantify radioactive components from decay of radon-222. During Phase A a new gamma detector was tested in full scale exposed to radon-222. New data analysis procedures for the correction for the influence of radon-222 inside the pipeline, where developed and its utility successfully demonstrated. During Phase B the new detector was mounted in a pipeline pig constructed for inspection of 30-inch gas pipelines. Working conditions were demonstrated in three runs through the southern route of the DONG owned 30-inch gas pipelines crossing the Danish strait named the Great Belt. The FSB-technology found 88% of the free spans identified with the latest acoustic survey. The FSB-technology found in addition 22 free spans that were termed ''invisible'', because they were not identified by the most recent acoustic survey. It is believed that ''invisible free spans'' are either real free spans or locations, where the pipeline has no or very little support from deposits in the pipeline trench. The FSB-survey confirmed all exposed sections longer than 20 metres found by the acoustic survey in the first 21 kilometre of the pipeline. However, the FSB-survey underestimated

  20. Boundary Spanning in Global Software Development

    DEFF Research Database (Denmark)

    Søderberg, Anne-Marie; Romani, Laurence

    imbalances of power, exacerbated in the case of an Indian vendor and a European client, need to be taken into account. The paper thus contributes with a more context sensitive understanding of inter-organizational boundary work. Taking the vendor perspective also leads to problematization of common...... of Indian IT vendor managers who are responsible for developing client relations and coordinating complex global development projects. The authors revise a framework of boundary spanning leadership practices to adapt it to an offshore outsourcing context. The empirical investigation highlights how...

  1. Decentralized Pricing in Minimum Cost Spanning Trees

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Moulin, Hervé; Østerdal, Lars Peter

    In the minimum cost spanning tree model we consider decentralized pricing rules, i.e. rules that cover at least the ecient cost while the price charged to each user only depends upon his own connection costs. We de ne a canonical pricing rule and provide two axiomatic characterizations. First......, the canonical pricing rule is the smallest among those that improve upon the Stand Alone bound, and are either superadditive or piece-wise linear in connection costs. Our second, direct characterization relies on two simple properties highlighting the special role of the source cost....

  2. Signal Enhancement with Variable Span Linear Filters

    DEFF Research Database (Denmark)

    Benesty, Jacob; Christensen, Mads Græsbøll; Jensen, Jesper Rindom

    . Variable span filters combine the ideas of optimal linear filters with those of subspace methods, as they involve the joint diagonalization of the correlation matrices of the desired signal and the noise. The book shows how some well-known filter designs, e.g. the minimum distortion, maximum signal...... the time and STFT domains, and, lastly, in time-domain binaural enhancement. In these contexts, the properties of these filters are analyzed in terms of their noise reduction capabilities and desired signal distortion, and the analyses are validated and further explored in simulations....

  3. Robustness of Long Span Reciprocal Timber Structures

    DEFF Research Database (Denmark)

    Balfroid, Nathalie; Kirkegaard, Poul Henning

    2011-01-01

    engineer may take necessary steps to design robust structures that are insensitive to accidental circumstances. The present paper makes a discussion of such robustness issues related to the future development of reciprocal timber structures. The paper concludes that these kind of structures can have...... a potential as long span timber structures in real projects if they are carefully designed with respect to the overall robustness strategies.......Robustness of structural systems has obtained a renewed interest due to a much more frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure. The interest has also been facilitated due to recently severe structural failures...

  4. Analysis of protection spanning-tree protocol

    Directory of Open Access Journals (Sweden)

    Б.Я. Корнієнко

    2007-01-01

    Full Text Available  Extraordinary sweeping  of  IT – development  causes vulnerabilities and, thereafter, attacks that use these vulnerabilities. That is why one must post factum or even in advance speed up invention of new information  security systems as well as develop the old ones. The matter of article concerns Spanning-Tree Protocol  – the vivid example of the case, when the cure of the vulnerability creates dozen of new "weak spots".

  5. Individual differences in phonological learning and verbal STM span.

    Science.gov (United States)

    Service, Elisabet; Maury, Sini; Luotoniemi, Emilia

    2007-07-01

    A relationship between phonological short-term memory tasks (e.g., nonword repetition, digit span) and vocabulary learning in both experimental and real-life conditions has been reported in numerous studies. A mechanism that would explain this correlation is, however, not known. The present study explores the possibility that it is the quality of phonological representations that affects both short-term recall and long-term learning of novel wordlike items. In Experiment 1, groups with relatively good and poor span for pseudowords were established. The good group was found to perform better at explicit memory tasks tapping the incidental learning of a limited stimulus pool used in an auditory immediate serial pseudoword recall task. In Experiment 2, the results of Experiment 1 were replicated when experience of correct recall was controlled. In Experiment 3, the immediate recall performance of the good group was found to benefit more than that of the poor group from syllable repetition within stimulus pools. It is concluded that the efficiency of a process that creates phonological representations is related both to short-term capacity for verbal items, and to long-term phonological learning of the structure of novel phonological items.

  6. Critical review of a new volcanic eruption chronology

    Science.gov (United States)

    Neuhäuser, Dagmar L.; Neuhäuser, Ralph

    2016-04-01

    Sigl. et al. (2015, Nature) present historical evidence for 32 volcanic eruptions to evaluate their new polar ice core 10-Be chronology - 24 are dated within three years of sulfur layers in polar ice. Most of them can be interpreted as weather phenomena (Babylonia: disk of sun like moon, reported for only one day, e.g. extinction due to clouds), Chinese sunspot reports (pellet, black vapor, etc.), solar eclipses, normal ice-halos and coronae (ring, bow, etc.), one aurora (redness), red suns due to mist drops in wet fog or fire-smoke, etc. Volcanic dust may facilitate detections of sunspots and formation of Bishop's ring, but tend to inhibit ice-halos, which are otherwise often reported in chronicles. We are left with three reports possibly indicating volcanic eruptions, namely fulfilling genuine criteria for atmospheric disturbances due to volcanic dust, e.g. bluish or faint sun, orange sky, or fainting of stars for months (BCE 208, 44-42, and 32). Among the volcanic eruptions used to fix the chronology (CE 536, 626, 939, 1257), the reports cited for the 930s deal only with 1-2 days, at least one reports an eclipse. In the new chronology, there is a sulfur detection eight years after the Vesuvius eruption, but none in CE 79. It may appear surprising that, from BCE 500 to 1, all five northern sulfur peaks labeled in figure 2 in Sigl et al. are systematically later by 2-4 years than the (corresponding?) southern peaks, while all five southern peaks from CE 100 to 600 labeled in figure 2 are systematically later by 1-4 years than the (corresponding?) northern peaks. Furthermore, in most of their six strongest volcanic eruptions, temperatures decreased years before their sulfur dating - correlated with weak solar activity as seen in radiocarbon, so that volcanic climate forcing appears dubious here. Also, their 10-Be peaks at CE 775 and 994 are neither significant nor certain in dating.

  7. Phonological similarity effect in complex span task.

    Science.gov (United States)

    Camos, Valérie; Mora, Gérôme; Barrouillet, Pierre

    2013-01-01

    The aim of our study was to test the hypothesis that two systems are involved in verbal working memory; one is specifically dedicated to the maintenance of phonological representations through verbal rehearsal while the other would maintain multimodal representations through attentional refreshing. This theoretical framework predicts that phonologically related phenomena such as the phonological similarity effect (PSE) should occur when the domain-specific system is involved in maintenance, but should disappear when concurrent articulation hinders its use. Impeding maintenance in the domain-general system by a concurrent attentional demand should impair recall performance without affecting PSE. In three experiments, we manipulated the concurrent articulation and the attentional demand induced by the processing component of complex span tasks in which participants had to maintain lists of either similar or dissimilar words. Confirming our predictions, PSE affected recall performance in complex span tasks. Although both the attentional demand and the articulatory requirement of the concurrent task impaired recall, only the induction of an articulatory suppression during maintenance made the PSE disappear. These results suggest a duality in the systems devoted to verbal maintenance in the short term, constraining models of working memory.

  8. The Problem of Predecessors on Spanning Trees

    Directory of Open Access Journals (Sweden)

    V. S. Poghosyan

    2011-01-01

    Full Text Available We consider the equiprobable distribution of spanning trees on the square lattice. All bonds of each tree can be oriented uniquely with respect to an arbitrary chosen site called the root. The problem of predecessors is to find the probability that a path along the oriented bonds passes sequentially fixed sites i and j. The conformal field theory for the Potts model predicts the fractal dimension of the path to be 5/4. Using this result, we show that the probability in the predecessors problem for two sites separated by large distance r decreases as P(r ∼ r −3/4. If sites i and j are nearest neighbors on the square lattice, the probability P(1 = 5/16 can be found from the analytical theory developed for the sandpile model. The known equivalence between the loop erased random walk (LERW and the directed path on the spanning tree states that P(1 is the probability for the LERW started at i to reach the neighboring site j. By analogy with the self-avoiding walk, P(1 can be called the return probability. Extensive Monte-Carlo simulations confirm the theoretical predictions.

  9. Chronology of Mercury's geological and geophysical evolution - the Vulcanoid hypothesis

    International Nuclear Information System (INIS)

    Leake, M.A.; Chapman, C.R.; Weidenschilling, S.J.; Davis, D.R.; Greenberg, R.

    1987-01-01

    The possibility that constraints on Mercury's chronology can be relaxed through reference to a Mercury-specific bombarding population of planetesimals interior to its orbit, and therefore only occasionally encountering the planet at times of secular perturbations, is investigated. While such vulcanoids may have been a significant source of early cratering, those in the pertinent orbits are depleted by mutual collisions and can therefore only furnish a modest extension of the heavy bombardment period. A search is conducted for vulcanoids further within Mercury's orbit; evidence that Mercury's intercrater plains are of volcanic origin is discussed. 99 references

  10. Gödel metrics with chronology protection in Horndeski gravities

    Science.gov (United States)

    Geng, Wei-Jian; Li, Shou-Long; Lü, H.; Wei, Hao

    2018-05-01

    Gödel universe, one of the most interesting exact solutions predicted by General Relativity, describes a homogeneous rotating universe containing naked closed time-like curves (CTCs). It was shown that such CTCs are the consequence of the null energy condition in General Relativity. In this paper, we show that the Gödel-type metrics with chronology protection can emerge in Einstein-Horndeski gravity. We construct such exact solutions also in Einstein-Horndeski-Maxwell and Einstein-Horndeski-Proca theories.

  11. Astronautics and Aeronautics: A Chronology, 1996-2000

    Science.gov (United States)

    Lewis, Marieke; Swanson, Ryan

    2009-01-01

    This report is a chronological compilation of narrative summaries of news reports and government documents highlighting significant events and developments in United States and foreign aeronautics and astronautics. It covers the years 1996 through 2000. These summaries provide a day-by-day recounting of major activities, such as administrative developments, awards, launches, scientific discoveries, corporate and government research results, and other events in countries with aeronautics and astronautics programs. Researchers used the archives and files housed in the NASA History Division, as well as reports and databases on the NASA Web site.

  12. Astronautics and Aeronautics: A Chronology, 2001-2005

    Science.gov (United States)

    Ivey, William Noel; Lewis, Marieke

    2010-01-01

    This report is a chronological compilation of narrative summaries of news reports and government documents highlighting significant events and developments in U.S. and foreign aeronautics and astronautics. It covers the years 2001 through 2005. These summaries provide a day-by-day recounting of major activities, such as administrative developments, awards, launches, scientific discoveries, corporate and government research results, and other events in countries with aeronautics and astronautics programs. Researchers used the archives and files housed in the NASA History Division, as well as reports and databases on the NASA Web site.

  13. Integrating chronological uncertainties for annually laminated lake sediments using layer counting, independent chronologies and Bayesian age modelling (Lake Ohau, South Island, New Zealand)

    Science.gov (United States)

    Vandergoes, Marcus J.; Howarth, Jamie D.; Dunbar, Gavin B.; Turnbull, Jocelyn C.; Roop, Heidi A.; Levy, Richard H.; Li, Xun; Prior, Christine; Norris, Margaret; Keller, Liz D.; Baisden, W. Troy; Ditchburn, Robert; Fitzsimons, Sean J.; Bronk Ramsey, Christopher

    2018-05-01

    Annually resolved (varved) lake sequences are important palaeoenvironmental archives as they offer a direct incremental dating technique for high-frequency reconstruction of environmental and climate change. Despite the importance of these records, establishing a robust chronology and quantifying its precision and accuracy (estimations of error) remains an essential but challenging component of their development. We outline an approach for building reliable independent chronologies, testing the accuracy of layer counts and integrating all chronological uncertainties to provide quantitative age and error estimates for varved lake sequences. The approach incorporates (1) layer counts and estimates of counting precision; (2) radiometric and biostratigrapic dating techniques to derive independent chronology; and (3) the application of Bayesian age modelling to produce an integrated age model. This approach is applied to a case study of an annually resolved sediment record from Lake Ohau, New Zealand. The most robust age model provides an average error of 72 years across the whole depth range. This represents a fractional uncertainty of ∼5%, higher than the <3% quoted for most published varve records. However, the age model and reported uncertainty represent the best fit between layer counts and independent chronology and the uncertainties account for both layer counting precision and the chronological accuracy of the layer counts. This integrated approach provides a more representative estimate of age uncertainty and therefore represents a statistically more robust chronology.

  14. Distribution and migration chronology of Eastern population sandhill cranes

    Science.gov (United States)

    Fronczak, David L.; Andersen, David; Hanna, Everett E.; Cooper, Thomas R.

    2017-01-01

    The Eastern Population (EP) of greater sandhill cranes (Antigone canadensis tabida; cranes) is expanding in size and geographic range. Little information exists regarding the geographic extent of breeding, migration, and wintering ranges, migration chronology, or use of staging areas for cranes in the EP. To obtain these data, we attached solar global positioning system (GPS) platform transmitting terminals (PTTs) to 42 sandhill cranes and monitored daily locations from December 2009 through August 2014. On average, tagged cranes settled in summer areas during late‐March in Minnesota (7%), Wisconsin (29%), Michigan, USA (21%), and Ontario, Canada (38%) and arrived at their winter terminus beginning mid‐December in Indiana (15%), Kentucky (3%), Tennessee (45%), Georgia (5%), and Florida (32%). Cranes initiated spring migration beginning mid‐February to their respective summer areas on routes similar to those used during fall migration. Twenty‐five marked cranes returned to the same summer area after a second spring migration, of which 19 (76%) settled cranes in the EP, we estimated that approximately 29–31% of cranes that summered in both Wisconsin and the Lower Peninsula of Michigan were not in areas included in the survey. The information we collected on crane movements provides insight into distribution and migration chronology that will aid in assessment of the current USFWS fall survey. In addition, information on specific use sites can assist state and federal managers to identify and protect key staging and winter areas particularly during current and future recreational harvest seasons.

  15. Chronological alterations of diagnostic imaging of renal cell carcinoma

    International Nuclear Information System (INIS)

    Arima, Kiminobu; Sugimura, Yoshiki; Yanagawa, Makoto; Tochigi, Hiromi; Kawamura, Juichi

    1994-01-01

    A review of 156 cases of renal cell carcinoma diagnosed during a 20-year period demonstrated the changes of initial signs/symptoms and imaging modalities for detection and definition. According to the imaging modality used for diagnosing renal cell carcinoma, clinical pictures were chronologically examined over 4 periods: 1973 to 1979 (before CT era), 1980 to 1984 (early CT era), 1985 to 1987 (CT era) and 1988 to 1992 (CT/MRI era). With regards to initial signs or symptoms, the proportion of classical trials has gradually decreased, while that of tumors noted incidentally has increased. As for imaging modalities for detection, the proportion of IVP has gradually decreased and that of CT and US has increased over the periods. With regard to imaging modalities for definition, the proportion of angiography has decreased and that of CT has increased. From chronological changes in clinical pictures and imaging modalities, we suggested a decision tree of imaging modalities for detection and definition of renal cell carcinoma. (author)

  16. Chronologic changes of free fat graft in rabbit using CT

    International Nuclear Information System (INIS)

    Kondo, Norihiro; Kurita, Kenichi; Yajima, Tetsuya; Izumi, Masahiro

    2008-01-01

    Free fat grafts are now used for preventing osteal readhesion, filling dead space, and protecting grafted nerves and vessels. However, it is reported that grafted fat tissue is unstable resulting in high risk of cicatrization and infection. We grafted free fat to a rabbit's back and observed the chronologic change using CT. Ten adult male Japanese white rabbits (3.5 kg) were used. In five rabbits, fat tissue was obtained from the back under general anaesthesia, and transplanted into the back about 50 mm posterior from the donor site. CT was taken in the fixed scan condition five times (preoperation, immediate postoperation, postoperative 1-month, 2-month, and 3-month). In the remaining five rabbits, only CT scan was taken three times as a control. It was observed that we compared preoperative fat volume with the postoperative volume using RealINTAGE. Grafted fat tissue decreased postoperatively at 1-month and completely disappeared at 3-months. We were able to prove that CT scan is effective to observe the chronologic change of grafted fat tissue. Techniques of tissue engineering are necessary for survival of grafted fat tissue. (author)

  17. Dental and Skeletal Maturity- A Biological Indicator of Chronologic Age

    Science.gov (United States)

    Saha, Sonali; Yadav, Gunjan; Tripathi, Abhay Mani; Grover, Kavita

    2014-01-01

    Introduction: Precise evaluation of the developmental stage of a child is not only an integral part of both diagnosis and treatment of paediatric patients; it is also essential in Forensic Medicine and Dentistry. Physiologic age can be estimated by somatic, sexual, skeletal and dental maturity. Aim: Investigate the relationship between the dental age (DA) and skeletal age (SA) of children and comparing it with the chronological age (CA). Materials and Methods: The dental age estimation methods of Schour and Massler (S&M), and Demirjian and Goldstien (D&G) and skeletal assessment methods of Greulich and Pyle (G&P), and Tanner et al., (TW2) were used to analyze the orthopantomograms and hand-wrist radiographs respectively of 150 healthy subjects within the age range of 5-15 y and compared with the Chronological Age. Statistical Analysis: Data collected was statistically analysed using the SPSS version 15.0 Statistical Analysis Software. For all tests p-value of <0.05 were considered statistically significance. Results: Dental age estimation techniques were found comparable and equally reliable as the skeletal age estimation methods. Strong correlations between dental and skeletal maturation were demonstrated. PMID:25386525

  18. A developing chronology for prehistoric 'moated sites' in northeast Thailand

    International Nuclear Information System (INIS)

    McGrath, R.J.; Boyd, W.E.

    1999-01-01

    Full text: Many mounded Iron Age occupation sites in the Mun River Valley,N.E. Thailand are characterised by distinctive encircling earthworks, these are commonly known as 'moated sites'. The first excavations of any significance within the moats themselves at six sites -Noen U-Loke, Non Muang Khao, Ban Non Khrua Chut, Ban Non Ngiu, Ban Makham Thae and Ban Non Wat - in the form of long trenches have been carried out to enable detailed examination of their structure. Significantly, the surficial morphology of the moats, and the notable regularity of shape and patterning of the moats in plan, usually does not accurately reflect the buried sectional morphology of incised channel features, which are in no way expressed on the surface. Buried channels beneath the edge of the mounds as well as the surrounding moat banks have also been revealed. Stratigraphic and geomorphic relationships of the buried features imply critical chronological relationships which need to be tested to allow full development of a model for the evolution of the archaeological sites. Extremely small quantities of charcoal and shells obtained from the buried features has necessitated the need for AMS dating to develop the chronology for the development, use and decline of the moated features and channels. The dating is an ongoing process, however, results thus far obtained supports the development of older channels towards the archaeological mounds, and yet older buried channels under the sites

  19. Image Segmentation Using Minimum Spanning Tree

    Science.gov (United States)

    Dewi, M. P.; Armiati, A.; Alvini, S.

    2018-04-01

    This research aim to segmented the digital image. The process of segmentation is to separate the object from the background. So the main object can be processed for the other purposes. Along with the development of technology in digital image processing application, the segmentation process becomes increasingly necessary. The segmented image which is the result of the segmentation process should accurate due to the next process need the interpretation of the information on the image. This article discussed the application of minimum spanning tree on graph in segmentation process of digital image. This method is able to separate an object from the background and the image will change to be the binary images. In this case, the object that being the focus is set in white, while the background is black or otherwise.

  20. Phonological similarity in working memory span tasks.

    Science.gov (United States)

    Chow, Michael; Macnamara, Brooke N; Conway, Andrew R A

    2016-08-01

    In a series of four experiments, we explored what conditions are sufficient to produce a phonological similarity facilitation effect in working memory span tasks. By using the same set of memoranda, but differing the secondary-task requirements across experiments, we showed that a phonological similarity facilitation effect is dependent upon the semantic relationship between the memoranda and the secondary-task stimuli, and is robust to changes in the representation, ordering, and pool size of the secondary-task stimuli. These findings are consistent with interference accounts of memory (Brown, Neath, & Chater, Psychological Review, 114, 539-576, 2007; Oberauer, Lewandowsky, Farrell, Jarrold, & Greaves, Psychonomic Bulletin & Review, 19, 779-819, 2012), whereby rhyming stimuli provide a form of categorical similarity that allows distractors to be excluded from retrieval at recall.