WorldWideScience

Sample records for chronological life span

  1. Quantifying yeast chronological life span by outgrowth of aged cells.

    Science.gov (United States)

    Murakami, Christopher; Kaeberlein, Matt

    2009-01-01

    The budding yeast Saccharomyces cerevisiae has proven to be an important model organism in the field of aging research. The replicative and chronological life spans are two established paradigms used to study aging in yeast. Replicative aging is defined as the number of daughter cells a single yeast mother cell produces before senescence; chronological aging is defined by the length of time cells can survive in a non-dividing, quiescence-like state. We have developed a high-throughput method for quantitative measurement of chronological life span. This method involves aging the cells in a defined medium under agitation and at constant temperature. At each age-point, a sub-population of cells is removed from the aging culture and inoculated into rich growth medium. A high-resolution growth curve is then obtained for this sub-population of aged cells using a Bioscreen C MBR machine. An algorithm is then applied to determine the relative proportion of viable cells in each sub-population based on the growth kinetics at each age-point. This method requires substantially less time and resources compared to other chronological lifespan assays while maintaining reproducibility and precision. The high-throughput nature of this assay should allow for large-scale genetic and chemical screens to identify novel longevity modifiers for further testing in more complex organisms. PMID:19421136

  2. Life spanning murine gene expression profiles in relation to chronological and pathological aging in multiple organs.

    Science.gov (United States)

    Jonker, Martijs J; Melis, Joost P M; Kuiper, Raoul V; van der Hoeven, Tessa V; Wackers, Paul F K; Robinson, Joke; van der Horst, Gijsbertus T J; Dollé, Martijn E T; Vijg, Jan; Breit, Timo M; Hoeijmakers, Jan H J; van Steeg, Harry

    2013-10-01

    Aging and age-related pathology is a result of a still incompletely understood intricate web of molecular and cellular processes. We present a C57BL/6J female mice in vivo aging study of five organs (liver, kidney, spleen, lung, and brain), in which we compare genome-wide gene expression profiles during chronological aging with pathological changes throughout the entire murine life span (13, 26, 52, 78, 104, and 130 weeks). Relating gene expression changes to chronological aging revealed many differentially expressed genes (DEGs), and altered gene sets (AGSs) were found in most organs, indicative of intraorgan generic aging processes. However, only ≤ 1% of these DEGs are found in all organs. For each organ, at least one of 18 tested pathological parameters showed a good age-predictive value, albeit with much inter- and intraindividual (organ) variation. Relating gene expression changes to pathology-related aging revealed correlated genes and gene sets, which made it possible to characterize the difference between biological and chronological aging. In liver, kidney, and brain, a limited number of overlapping pathology-related AGSs were found. Immune responses appeared to be common, yet the changes were specific in most organs. Furthermore, changes were observed in energy homeostasis, reactive oxygen species, cell cycle, cell motility, and DNA damage. Comparison of chronological and pathology-related AGSs revealed substantial overlap and interesting differences. For example, the presence of immune processes in liver pathology-related AGSs that were not detected in chronological aging. The many cellular processes that are only found employing aging-related pathology could provide important new insights into the progress of aging. PMID:23795901

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

    Science.gov (United States)

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

    2015-10-16

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

  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. Life-spanning murine gene expression profiles in relation to chronological and pathological aging in multiple organs

    Science.gov (United States)

    Kuiper, Raoul V; van der Hoeven, Tessa V; Wackers, P.F.K.; Robinson, Joke; van der Horst, Gijsbertus TJ; Dollé, Martijn ET; Vijg, Jan; Breit, Timo M; Hoeijmakers, Jan HJ; van Steeg, Harry

    2013-01-01

    Summary Aging and age-related pathology is a result of a still incompletely-understood intricate web of molecular and cellular processes. We present a C57BL/6J female mice in vivo aging study of five organs (liver, kidney, spleen, lung and brain), in which we compare genome-wide gene expression profiles during chronological aging with pathological changes throughout the entire murine lifespan (13, 26, 52, 78, 104 and 130 weeks). Relating gene expression changes to chronological aging revealed many differentially expressed genes (DEGs) and altered gene-sets (AGSs) were found in most organs, indicative of intra-organ generic aging processes. However, only ≤ 1% of these DEGs are found in all organs. For each organ, at least one of 18 tested pathological parameters showed a good age-predictive value, albeit with much inter- and intra-individual (organ) variation. Relating gene expression changes to pathology-related aging revealed correlated genes and gene-sets, which made it possible to characterize the difference between biological and chronological aging. In liver, kidney and brain, a limited number of overlapping pathology-related AGSs were found. Immune responses appeared to be common, yet the changes were specific in most organs. Furthermore, changes were observed in energy homeostasis, reactive oxygen species, cell cycle, cell motility and DNA damage. Comparison of chronological and pathology-related AGSs revealed substantial overlap and interesting differences. For example, the presence of immune processes in liver pathology-related AGSs which were not detected in chronological aging. The many cellular processes that are only found employing aging–related pathology could provide important new insights into the progress of aging. PMID:23795901

  6. Life Span Developmental Approach

    OpenAIRE

    Eryılmaz, Ali

    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. 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

  9. Thermodynamics and life span estimation

    International Nuclear Information System (INIS)

    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

  10. Loneliness Across the Life Span

    NARCIS (Netherlands)

    Qualter, Pamela; Vanhalst, Janne; Harris, Rebecca; Van Roekel, Eeske; Lodder, Gerine; Bangee, Munirah; Maes, Marlies; Verhagen, Maaike

    2015-01-01

    Most people have experienced loneliness and have been able to overcome it to reconnect with other people. In the current review, we provide a life-span perspective on one component of the evolutionary theory of lonelinessa component we refer to as the reaffiliation motive (RAM). The RAM represents t

  11. Elevated histone expression promotes life span extension.

    Science.gov (United States)

    Feser, Jason; Truong, David; Das, Chandrima; Carson, Joshua J; Kieft, Jeffrey; Harkness, Troy; Tyler, Jessica K

    2010-09-10

    Changes to the chromatin structure accompany aging, but the molecular mechanisms underlying aging and the accompanying changes to the chromatin are unclear. Here, we report a mechanism whereby altering chromatin structure regulates life span. We show that normal aging is accompanied by a profound loss of histone proteins from the genome. Indeed, yeast lacking the histone chaperone Asf1 or acetylation of histone H3 on lysine 56 are short lived, and this appears to be at least partly due to their having decreased histone levels. Conversely, increasing the histone supply by inactivation of the histone information regulator (Hir) complex or overexpression of histones dramatically extends life span via a pathway that is distinct from previously known pathways of life span extension. This study indicates that maintenance of the fundamental chromatin structure is critical for slowing down the aging process and reveals that increasing the histone supply extends life span. PMID:20832724

  12. Life span of the biosphere

    Science.gov (United States)

    Lovelock, J. E.; Whitfield, M.

    1982-04-01

    Since main sequence stars appear to increase their burning rate as they age, the sun may be thought to have increased its output by 30% since the earth's origin 4.5 billion years ago. Due to the requirement for some means of planetary thermostasis in the maintenance of an equable climate since life began, possible links are considered between the biological, Gaia hypothesis of Lovelock and Margulis (1974) for climate control, and Walker et al's (in press) model of automatic thermostasis, in which the abundance of such atmospheric greenhouse gases as CO2 adjusts to resist the warming tendency of the increased solar flux. It is concluded that, since atmospheric CO2 is now close to its partial pressure lower limit, the biosphere will on a geological time-scale be soon exposed, without protection, to the predicted solar luminosity increases.

  13. The Cost of Uncertain Life Span

    OpenAIRE

    Edwards, Ryan D.

    2008-01-01

    A considerable amount of uncertainty surrounds life expectancy, the average length of life. The standard deviation in adult life span is about 15 years in the U.S., and theory and evidence suggest it is costly. I calibrate a utility-theoretic model of preferences over length of life and show that one less year in standard deviation is worth about half a mean life year. Differences in the standard deviation exacerbate cross-sectional differences in life expectancy between the U.S. and other in...

  14. Atomic Bomb Survivors Life-Span Study

    OpenAIRE

    Socol, Yehoshua; Dobrzyński, Ludwik

    2015-01-01

    The atomic bomb survivors life-span study (LSS) is often claimed to support the linear no-threshold hypothesis (LNTH) of radiation carcinogenesis. This paper shows that this claim is baseless. The LSS data are equally or better described by an s-shaped dependence on radiation exposure with a threshold of about 0.3 Sievert (Sv) and saturation level at about 1.5 Sv. A Monte-Carlo simulation of possible LSS outcomes demonstrates that, given the weak statistical power, LSS cannot provide support ...

  15. Life span study report, 11, part 2

    International Nuclear Information System (INIS)

    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)

  16. Life span study report 9, part 3

    International Nuclear Information System (INIS)

    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)

  17. Atomic Bomb Survivors Life-Span Study

    Science.gov (United States)

    Dobrzyński, Ludwik

    2015-01-01

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

  18. Data resources for life span study

    International Nuclear Information System (INIS)

    The Life Span Study sample consists originally of 82,000 A-bomb survivors who were enumerated from a nation-wide A-bomb survivors survey conducted in 1950 and 27,000 non-exposed individuals. Mortality ascertainment is essentially complete by periodic checks against Koseki, but its weakness is the inexactness of the cause of death stated on the death certificate. Some of the latter can be compensated for by collateral use of autopsy information and the data from Tissue and Tumor Registries. Updating of the Hiroshima Tumor Registry has been recently completed and no serious bias related to radiation dose was observed in the data collection for either Hiroshima or Nagasaki. Also the completeness of registration is the highest among registries in Japan. The Tumor and Tissue Registries should be very useful data resources to determine the radiation effects on non-fatal cancers i.e., thyroid and breast cancers as well as the fatal types. Lack of information on the out-migrated subjects from the two cities should be seriously considered, especially those who were of young age at the time of the bombing. Information on environmental factors other than radiation exposure, such as occupation, smoking and diet, has been collected by interviewers, mail questionnaires or record linkage with census data, since 1960. Such information is also currently obtained on a case-control basis for certain sites of cancer, such as breast, lung, colon and rectum, in this cohort. 11 references, 6 tables

  19. Life span study report, 9; 1950-78

    International Nuclear Information System (INIS)

    The RERF life span study report 9 consists of three parts and supplementary tables, each bound separately. Life span study report 9 supplementary tables, supplement to TR 12-80 and TR 5-81, are computer pritouts containing the life span study data from 1950-78. These tables are pertinent only to part 1 (Cancer mortality among atomic bomb survivors, 1950-78) and part 2 (Mortality from causes other than cancer among atomic bomb survivors, 1950-78) of Life span study report 9. This study extends Life span study report 8 by four years from 1975-78. These tables are included following data: The life span study sample, Death certificate data by cause, Malignant neoplasms, Neoplasms generally, Diseases other than neoplasms, Injuries and accidents, Summary of death certificate data. (J.P.N.)

  20. A Motivational Theory of Life-Span Development

    OpenAIRE

    Heckhausen, Jutta; Wrosch, Carsten; Schulz, Richard

    2010-01-01

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

  1. 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…

  2. Boundaries of life: estimating the life span of the biosphere

    Science.gov (United States)

    Franck, S.; Bounama, C.; von Bloh, W.

    We present a minimal model for the global carbon cycle of the Earth containing the reservoirs mantle ocean floor continental crust continental biosphere and the Kerogen as well as the aggregated reservoir ocean and atmosphere and obtain reasonable values for the present distribution of carbon in the surface reservoirs of the Earth The Earth system model for the long-term carbon cycle is specified by introducing three different types of biosphere prokaryotes eucaryotes and complex multicellular life They are characterized by different global temperature tolerance windows prokaryotes 2oC 100oC eucaryotes 5oC 45oC complex multicellular life 0oC 30oC From the Archaean to the future there always exists a prokaryotic biosphere 2 Gyr ago eucaryotic life first appears because the global surface temperature reaches the tolerance window for eucaryotes The emergence of complex multicellular life is connected with an explosive increase in biomass and a strong decrease in Cambrian global surface temperature at about 0 54 Gyr ago In the long-term future the three types of biosphere will die out in reverse sequence of their appearance For realistic values of the biotic enhancement of weathering there is no bistability in the future solutions for complex life Therefore complex organisms will not extinct by an implosion in comparison to the Cambrian explosion Eucaryotes and complex life become extinct because of too high surface temperatures in the future The ultimate life span of the biosphere is defined by the extinction of procaryotes in about 1 6 Gyr

  3. Mating System Transitions Drive Life Span Evolution in Pristionchus Nematodes.

    Science.gov (United States)

    Weadick, Cameron J; Sommer, Ralf J

    2016-04-01

    Interactions between the sexes influence evolution at many scales, but not all animal species conform to the familiar male-female (dioecious) mating system; such taxa are powerful tools for studying the evolutionary importance of sexual selection and conflict on all manner of life-history traits, including longevity. We tested for an effect of mating system on adult life span in Pristionchus nematodes, where self-fertile hermaphrodites have replaced females multiple times independently throughout the genus (androdioecy). By measuring adult life span for 11 species (6 dioecious, 5 androdioecious), we found that life span is considerably shorter in hermaphrodites relative to closely related females. This effect is not a cost of reproduction; brood size did not reliably trade off with life span in self-fertilizing hermaphrodites or in mated females. Furthermore, we found that sexual dimorphism in life span varied among dioecious species, with females generally outliving males. Finally, we documented intraspecific variation for life span and cuticular disease (blistering) prevalence in Pristionchus pacificus, a model system for evolutionary-developmental biology. This work demonstrates that mating system transitions and life span evolution are linked in Pristionchus nematodes and provides a foundation for future comparative and mechanistic studies of aging in this genus. PMID:27028079

  4. Brain Weight and Life-Span in Primate Species

    OpenAIRE

    Allman, J; McLaughlin, T.; A Hakeem

    1993-01-01

    In haplorhine primates (tarsiers, monkeys, apes, and humans), there is a significant correlation between brain weight and maximum life-span when the effect of body size is removed. There is also a significant correlation in haplorhine primates between brain weight and female age at first reproduction. For strepsirhine primates (lorises and lemurs), there are no significant correlations between brain weight and either life-span or female reproductive age when the effect of body size is removed...

  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. Elders’ Attitudes toward Extending the Healthy Life Span

    OpenAIRE

    Cicirelli, Victor G.

    2011-01-01

    Despite continuing debate between anti-aging researchers seeking major life span extension and concerned gerontologists and bioethicists, elders’ views have received little research attention. Study aimed to relate elders’ attitudes toward strong life span extension to psychosocial and background factors. Participants were 109 American elders (65% women) aged 60-99 (M = 77.08, SD = 9.05). Measures included attitudes toward living long and living forever, Desired Age, Death Acceptance, Goal...

  7. IS LIFE-SPAN UNDER OUR CONTROL??

    Directory of Open Access Journals (Sweden)

    Parle Milind

    2011-01-01

    Full Text Available With each passing day, we age. Our body gets flooded with unwanted and deleterious elements, our cells lose their ability to divide, our nervous, endocrine and immune systems weaken with advancing age. Sagging skin, wrinkled face, graying hair, loss of muscle strength, reduced reflexes, low energy levels, increasing fat, faulty memory (dementia, weak immunity, impaired vision, defective hearing, decreased libido, cardiovascular problems and neurodegenerative disorders (like Parkinsonism and Alzheimer’s disease are the characteristic features of ageing. Leading a disease free, long life (longevity has been a dream of mankind since the arrival of human race on the planet Earth. We can not reverse the ageing process, but the features associated with ageing can be delayed in order to improve the quality of life. The present review article focuses on different theories of ageing and the anti-ageing effects of Green tea, Garlic, Turmeric, Ashwagandha, Tomato, Anwala, Ginger, Aloe and Tulsi.

  8. A life span model of successful aging.

    Science.gov (United States)

    Schulz, R; Heckhausen, J

    1996-07-01

    To lay the foundation for our model, we first describe existing conceptions of successful aging, underlying assumptions of development, and criteria for success. The model presented extends the discourse on this topic in three directions: (a) It frames the discussion of successful aging in the broader context of life course development; (b) it accounts for both normative and nonnormative (i.e., exceptional) success; and (c) it integrates motivational processes into a theory of successful aging. Successful aging is equated with the development and maintenance of primary control throughout the life course, which is achieved through control-related processes that optimize selection and failure compensation functions. Selection processes regulate the choice of action goals so that diversity is maintained and positive and negative trade-offs between performance domains and life stages are taken into account. Compensation mechanisms serve to maintain, enhance, and remediate competencies and motivational resources after failure experiences. Both compensation and selection processes are motivated by desires for primary control and can be characterized in terms of primary and secondary control processes. PMID:8694390

  9. 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...

  10. Adaptive prolonged postreproductive life span in killer whales.

    Science.gov (United States)

    Foster, Emma A; Franks, Daniel W; Mazzi, Sonia; Darden, Safi K; Balcomb, Ken C; Ford, John K B; Croft, Darren P

    2012-09-14

    Prolonged life after reproduction is difficult to explain evolutionarily unless it arises as a physiological side effect of increased longevity or it benefits related individuals (i.e., increases inclusive fitness). There is little evidence that postreproductive life spans are adaptive in nonhuman animals. By using multigenerational records for two killer whale (Orcinus orca) populations in which females can live for decades after their final parturition, we show that postreproductive mothers increase the survival of offspring, particularly their older male offspring. This finding may explain why female killer whales have evolved the longest postreproductive life span of all nonhuman animals. PMID:22984064

  11. Telomere length correlates with life span of dog breeds.

    Science.gov (United States)

    Fick, Laura J; Fick, Gordon H; Li, Zichen; Cao, Eric; Bao, Bo; Heffelfinger, Doug; Parker, Heidi G; Ostrander, Elaine A; Riabowol, Karl

    2012-12-27

    Telomeric DNA repeats are lost as normal somatic cells replicate. When telomeres reach a critically short length, a DNA damage signal is initiated, inducing cell senescence. Some studies have indicated that telomere length correlates with mortality, suggesting that telomere length contributes to human life span; however, other studies report no correlation, and thus the issue remains controversial. Domestic dogs show parallels in telomere biology to humans, with similar telomere length, telomere attrition, and absence of somatic cell telomerase activity. Using this model, we find that peripheral blood mononuclear cell (PBMC) telomere length is a strong predictor of average life span among 15 different breeds (p Dogs lose telomeric DNA ~10-fold faster than humans, which is similar to the ratio of average life spans between these species. Breeds with shorter mean telomere lengths show an increased probability of death from cardiovascular disease, which was previously correlated with short telomere length in humans. PMID:23260664

  12. 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.

  13. Telomere Length Correlates with Life Span of Dog Breeds

    Directory of Open Access Journals (Sweden)

    Laura J. Fick

    2012-12-01

    Full Text Available Telomeric DNA repeats are lost as normal somatic cells replicate. When telomeres reach a critically short length, a DNA damage signal is initiated, inducing cell senescence. Some studies have indicated that telomere length correlates with mortality, suggesting that telomere length contributes to human life span; however, other studies report no correlation, and thus the issue remains controversial. Domestic dogs show parallels in telomere biology to humans, with similar telomere length, telomere attrition, and absence of somatic cell telomerase activity. Using this model, we find that peripheral blood mononuclear cell (PBMC telomere length is a strong predictor of average life span among 15 different breeds (p < 0.0001, consistent with telomeres playing a role in life span determination. Dogs lose telomeric DNA ∼10-fold faster than humans, which is similar to the ratio of average life spans between these species. Breeds with shorter mean telomere lengths show an increased probability of death from cardiovascular disease, which was previously correlated with short telomere length in humans.

  14. 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...

  15. 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…

  16. [Microgravity, life span and biological age of animals].

    Science.gov (United States)

    Serova, L V

    2002-01-01

    Summarized are author's and literary data about the microgravity effects on life span and biological age of animals obtained in experiments with laboratory rats flown in biosatellites Kosmos. Exposure of rats in the spaceflight microgravity as long as 3 wk. (up to 1/50th of the life period of this species) did not reduce the life span post flight. Alterations in biological age as judged by the reproductive function, general resistance and tissue regeneration rate were minor and in a number of parameters were significantly less as compared with the shifts resulting from simulation of the physiological effects of microgravity in laboratory (for a similar period). Prospects of investigations into this problem are considered. PMID:12442585

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

    OpenAIRE

    Gilleard, C.; Higgs, P.

    2015-01-01

    The life course has become a topic of growing interest within the social sciences. Attempts to link this sub-discipline with life span developmental psychology have been called for but with little sign of success. In this paper, we seek to address three interlinked issues concerning the potential for a more productive interchange between life course sociology and life span psychology. The first is to try to account for the failure of these two sub-disciplines to achieve any deepening engageme...

  18. Telomere Length Correlates with Life Span of Dog Breeds

    OpenAIRE

    Laura J. Fick; Gordon H. Fick; Zichen Li; Eric Cao; Bo Bao; Doug Heffelfinger; Heidi G. Parker; Elaine A. Ostrander; Karl Riabowol

    2012-01-01

    Telomeric DNA repeats are lost as normal somatic cells replicate. When telomeres reach a critically short length, a DNA damage signal is initiated, inducing cell senescence. Some studies have indicated that telomere length correlates with mortality, suggesting that telomere length contributes to human life span; however, other studies report no correlation, and thus the issue remains controversial. Domestic dogs show parallels in telomere biology to humans, with similar telomere length, telom...

  19. Minocycline Effect on Life and Health Span of Drosophila Melanogaster

    OpenAIRE

    Oxenkrug, Gregory; Navrotskaya, Valeriya; Vorobyova, Lyudmila; Summergrad, Paul

    2012-01-01

    Up-regulation of kynurenine (KYN) pathway of tryptophan (TRP) was suggested as one of the mechanisms of aging and aging-associated disorders. Genetic and pharmacological impairment of TRP – KYN metabolism resulted in prolongation of life span in Drosophila models. Minocycline, an antibiotic with anti-inflammatory, antioxidant and neuroprotective properties independent of its antibacterial activity, inhibited KYN formation from TRP. Since minocycline is the only FDA approved for human use medi...

  20. Exercise, brain, and cognition across the life span

    OpenAIRE

    Voss, Michelle W.; Nagamatsu, Lindsay S.; Liu-Ambrose, Teresa; Arthur F Kramer

    2011-01-01

    This is a brief review of current evidence for the relationships between physical activity and exercise and the brain and cognition throughout the life span in non-pathological populations. We focus on the effects of both aerobic and resistance training and provide a brief overview of potential neurobiological mechanisms derived from non-human animal models. Whereas research has focused primarily on the benefits of aerobic exercise in youth and young adult populations, there is growing eviden...

  1. 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.

  2. 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

  3. 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...

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

    International Nuclear Information System (INIS)

    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

  5. The Chronology of the Life and Work of Jan Hus

    Czech Academy of Sciences Publication Activity Database

    Pavlíček, Ota

    Leiden : Brill, 2015 - (Šmahel, F.; Pavlíček, O.), s. 9-68 ISBN 978-90-04-28055-7. - (Brill's Companions to the Christian Tradition. 54) R&D Projects: GA AV ČR(CZ) KJB900090903 Institutional support: RVO:67985955 Keywords : Jan Hus * Hus's life * Hus's work * Bohemian Reformation * Council of Constance * Prague University Subject RIV: AB - History

  6. Explanations of a magic trick across the life span

    Directory of Open Access Journals (Sweden)

    Jay A Olson

    2015-03-01

    Full Text Available Studying how children and adults explain magic tricks can reveal developmental differences in cognition. We showed 167 children (aged 4 to 13 years a video of a magician making a pen vanish and asked them to explain the trick. Although most claimed to know the secret, none of them correctly identified it. The younger children provided more supernatural interpretations and more often took the magician’s actions at face value. Combined with a similar study of adults (N=1008, we found that both young children and older adults were particularly overconfident in their explanations of the trick. Our methodology demonstrates the feasibility of using magic to study cognitive development across the life span.

  7. Adults' conceptions of intelligence across the adult life span.

    Science.gov (United States)

    Berg, C A; Sternberg, R J

    1992-06-01

    To examine whether young, middle-aged, and older adults view the concept of intelligent person as similar or different during adulthood, 140 adults of various ages rated how likely it would be for individuals of average and exceptional intelligence at 30, 50, and 70 years of age to be engaged in behaviors previously identified by adults as characterizing adult intelligence. Adults perceived more similarity between exceptionally intelligent prototypes of closer ages (i.e., 30 and 50 and 50 and 70). Intelligence was perceived to consist of interest and ability to deal with novelty, everyday competence, and verbal competence--dimensions that were perceived to be differentially important for different-aged prototypes and by individuals of different ages. Participants' conceptions also included the idea that intelligence is malleable and that abilities differentially increase or decrease across the life span. PMID:1610512

  8. Transition: Life-Span and Life-Space Considerations for Empowerment.

    Science.gov (United States)

    Szymanski, Edna Mora

    1994-01-01

    This article integrates literature from counseling, rehabilitation, multicultural education, and special education to explain the importance of life-span considerations, including the preschool and early school years, and the life-space factors of family, culture, and community. Principles for transition interventions which promote empowerment are…

  9. Colour constancy across the life span: evidence for compensatory mechanisms.

    Science.gov (United States)

    Wuerger, Sophie

    2013-01-01

    It is well known that the peripheral visual system declines with age: the yellowing of the lens causes a selective reduction of short-wavelength light and sensitivity losses occur in the cone receptor mechanisms. At the same time, our subjective experience of colour does not change with age. The main purpose of this large-scale study (n = 185) covering a wide age range of colour-normal observers (18-75 years of age) was to assess the extent to which the human visual system is able to compensate for the changes in the optical media and at which level of processing this compensation is likely to occur. We report two main results: (1) Supra-threshold parafoveal colour perception remains largely unaffected by the age-related changes in the optical media (yellowing of the lens) whereas our ability to discriminate between small colour differences is compromised with an increase in age. (2) Significant changes in colour appearance are only found for unique green settings under daylight viewing condition which is consistent with the idea that the yellow-blue mechanism is most affected by an increase in age due to selective attenuation of short-wavelength light. The data on the invariance of hue perception, in conjunction with the age-related decline in chromatic sensitivity, provides evidence for compensatory mechanisms that enable colour-normal human observers a large degree of colour constancy across the life span. These compensatory mechanisms are likely to originate at cortical sites. PMID:23667689

  10. Resveratrol Fails to Extend Life Span in the Mosquito Anopheles stephensi.

    Science.gov (United States)

    Johnson, Adiv A; Riehle, Michael A

    2015-10-01

    Resveratrol, a plant polyphenol present in grape skins, has been theorized to account for the "French Paradox" by explaining how red wine may decrease the health risks associated with unhealthy diets. Resveratrol has been reported to extend life span in several different species. Other studies, however, have failed to find a resveratrol-induced life span effect. A recent meta-study analyzing previously published survival data concluded that, although resveratrol reliably and reproducibly extends life span in some species, its life span effects show diminished reliability in other organisms. The data are mixed, and it remains unclear how evolutionarily conserved resveratrol's effects on life span are. To gain further insight into this controversy, we studied the effects of various concentrations (200 μM, 100 μM, 50 μM, or 0 μM) of orally fed resveratrol on the life span of the mosquito Anopheles stephensi, an important vector of human malaria, under two different feeding treatments--sugar-fed only or sugar-fed with intermittent blood meals. Each treatment was repeated three times and both survivorship and mortality rates were analyzed for each replicate. For the majority of experiments, resveratrol failed to mediate a statistically significant effect on life span. Although there was one instance where resveratrol significantly increased life span, there were five other instances where resveratrol significantly decreased life span. We conclude from these data that, under normal conditions, resveratrol does not extend life span in A. stephensi. PMID:25848933

  11. Colour constancy across the life span: evidence for compensatory mechanisms.

    Directory of Open Access Journals (Sweden)

    Sophie Wuerger

    Full Text Available It is well known that the peripheral visual system declines with age: the yellowing of the lens causes a selective reduction of short-wavelength light and sensitivity losses occur in the cone receptor mechanisms. At the same time, our subjective experience of colour does not change with age. The main purpose of this large-scale study (n = 185 covering a wide age range of colour-normal observers (18-75 years of age was to assess the extent to which the human visual system is able to compensate for the changes in the optical media and at which level of processing this compensation is likely to occur. We report two main results: (1 Supra-threshold parafoveal colour perception remains largely unaffected by the age-related changes in the optical media (yellowing of the lens whereas our ability to discriminate between small colour differences is compromised with an increase in age. (2 Significant changes in colour appearance are only found for unique green settings under daylight viewing condition which is consistent with the idea that the yellow-blue mechanism is most affected by an increase in age due to selective attenuation of short-wavelength light. The data on the invariance of hue perception, in conjunction with the age-related decline in chromatic sensitivity, provides evidence for compensatory mechanisms that enable colour-normal human observers a large degree of colour constancy across the life span. These compensatory mechanisms are likely to originate at cortical sites.

  12. Angiotensin Converting Enzyme (ACE) Inhibitor Extends Caenorhabditis elegans Life Span.

    Science.gov (United States)

    Kumar, Sandeep; Dietrich, Nicholas; Kornfeld, Kerry

    2016-02-01

    Animal aging is characterized by progressive, degenerative changes in many organ systems. Because age-related degeneration is a major contributor to disability and death in humans, treatments that delay age-related degeneration are desirable. However, no drugs that delay normal human aging are currently available. To identify drugs that delay age-related degeneration, we used the powerful Caenorhabditis elegans model system to screen for FDA-approved drugs that can extend the adult lifespan of worms. Here we show that captopril extended mean lifespan. Captopril is an angiotensin-converting enzyme (ACE) inhibitor used to treat high blood pressure in humans. To explore the mechanism of captopril, we analyzed the acn-1 gene that encodes the C. elegans homolog of ACE. Reducing the activity of acn-1 extended the mean life span. Furthermore, reducing the activity of acn-1 delayed age-related degenerative changes and increased stress resistance, indicating that acn-1 influences aging. Captopril could not further extend the lifespan of animals with reduced acn-1, suggesting they function in the same pathway; we propose that captopril inhibits acn-1 to extend lifespan. To define the relationship with previously characterized longevity pathways, we analyzed mutant animals. The lifespan extension caused by reducing the activity of acn-1 was additive with caloric restriction and mitochondrial insufficiency, and did not require sir-2.1, hsf-1 or rict-1, suggesting that acn-1 functions by a distinct mechanism. The interactions with the insulin/IGF-1 pathway were complex, since the lifespan extensions caused by captopril and reducing acn-1 activity were additive with daf-2 and age-1 but required daf-16. Captopril treatment and reducing acn-1 activity caused similar effects in a wide range of genetic backgrounds, consistent with the model that they act by the same mechanism. These results identify a new drug and a new gene that can extend the lifespan of worms and suggest new

  13. Angiotensin Converting Enzyme (ACE Inhibitor Extends Caenorhabditis elegans Life Span.

    Directory of Open Access Journals (Sweden)

    Sandeep Kumar

    2016-02-01

    Full Text Available Animal aging is characterized by progressive, degenerative changes in many organ systems. Because age-related degeneration is a major contributor to disability and death in humans, treatments that delay age-related degeneration are desirable. However, no drugs that delay normal human aging are currently available. To identify drugs that delay age-related degeneration, we used the powerful Caenorhabditis elegans model system to screen for FDA-approved drugs that can extend the adult lifespan of worms. Here we show that captopril extended mean lifespan. Captopril is an angiotensin-converting enzyme (ACE inhibitor used to treat high blood pressure in humans. To explore the mechanism of captopril, we analyzed the acn-1 gene that encodes the C. elegans homolog of ACE. Reducing the activity of acn-1 extended the mean life span. Furthermore, reducing the activity of acn-1 delayed age-related degenerative changes and increased stress resistance, indicating that acn-1 influences aging. Captopril could not further extend the lifespan of animals with reduced acn-1, suggesting they function in the same pathway; we propose that captopril inhibits acn-1 to extend lifespan. To define the relationship with previously characterized longevity pathways, we analyzed mutant animals. The lifespan extension caused by reducing the activity of acn-1 was additive with caloric restriction and mitochondrial insufficiency, and did not require sir-2.1, hsf-1 or rict-1, suggesting that acn-1 functions by a distinct mechanism. The interactions with the insulin/IGF-1 pathway were complex, since the lifespan extensions caused by captopril and reducing acn-1 activity were additive with daf-2 and age-1 but required daf-16. Captopril treatment and reducing acn-1 activity caused similar effects in a wide range of genetic backgrounds, consistent with the model that they act by the same mechanism. These results identify a new drug and a new gene that can extend the lifespan of worms

  14. 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. PMID:21942279

  15. The Rate of Source Memory Decline across the Adult Life Span

    Science.gov (United States)

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

    2013-01-01

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

  16. 7 CFR 701.37 - Loss of control of the property during the practice life span.

    Science.gov (United States)

    2010-01-01

    ... the property during the practice life span. In the event of voluntary or involuntary loss of control... 7 Agriculture 7 2010-01-01 2010-01-01 false Loss of control of the property during the practice life span. 701.37 Section 701.37 Agriculture Regulations of the Department of Agriculture...

  17. Sequential and Coordinative Processing Dynamics in Figural Transformations across the Life Span.

    Science.gov (United States)

    Mayr, Ulrich; And Others

    1996-01-01

    Investigated the proposition that two distinct factors involved in life span cognitive development are mental speed and coordination efficiency. Results show dissociable speed of processing and working memory functioning over the life span and age-related differential effects of coordinative demands. (ET)

  18. The yeast forkhead HCM1 controls life span independent of calorie restriction.

    Science.gov (United States)

    Maoz, Noam; Gabay, Orshay; Waldman Ben-Asher, Hiba; Cohen, Haim Y

    2015-04-01

    Regulation of life span by members of the forkhead transcription factor family of proteins is one of the most highly investigated pathways in the field of aging. Nevertheless, despite the existence of forkhead family homologues in yeast, our knowledge of these proteins' role in yeast longevity is limited. Here, we show that yeast Hcm1p forkhead is the closest homologue of the worm PHA-4 forkhead, which regulates Caenorhabditis elegans life span. Overexpressing the yeast forkhead HCM1 or its deficiency resulted in a significant extension or reduction in yeast replicative life span, respectively. HCM1 regulates stress resistance, significantly increases the mRNA levels of several stress response genes including the catalase enzymes CTA1 and CTT1, and positively regulates life span independently of calorie restriction. Thus, HCM1 is a key regulator of life span, through a mechanism independent of calorie restriction. PMID:24835838

  19. Optimisation by Selection and Compensation: Balancing Primary and Secondary Control in Life Span Development.

    Science.gov (United States)

    Heckhausen, Jutta; Schulz, Richard

    1993-01-01

    Discusses individuals as producers of their life span developments, and examines individuals' selection of their life paths and their proneness to failure. Considers a model that explains individuals' optimization of their life course management in terms of selection of life paths and compensation for age-related losses such that potential for…

  20. Mathematical Basis of Idea That Harmonious Marriage Can Lengthen Life-span

    Institute of Scientific and Technical Information of China (English)

    Zhi-qiang Zhang

    2009-01-01

    It is a very important issue for us to explore the effects of the marriage to life. In recent years, many scholars have proved that the marriage can lengthen life-span from different angles. With the development of theory of dependence random variables, we discuss the effects of the marriage to life and provide a mathematical basis of the idea that the harmonious marriage can lengthen life-span in this paper. Meanwhile, we analyze the impact of the marriage on life on the basis of the net single premium.

  1. LIFE SPAN OF A SMOOTH SOLUTION FOR THE SURFACE DIFFUSION FLOW

    Institute of Scientific and Technical Information of China (English)

    刘祖汉

    2003-01-01

    Consider the motion of immersed hypersurfaces driven by surface diffusion flow and give anlower bound on the life span of a smooth immersed solution, which depends only on how muchthe curvature of the initial surface is concentrated in space.

  2. Berberine Prolongs Life Span and Stimulates Locomotor Activity of Drosophila melanogaster

    OpenAIRE

    Navrotskaya, V. V.; Oxenkrug, G.; Vorobyova, L. I.; Summergrad, P.

    2012-01-01

    Drosophila melanogaster mutants with deficient kynurenine (KYN) formation from tryptophan (TRP) have longer life span than wild type flies. Administration of alpha-methyl-TRP and 5-methyl-TRY, the inhibitors of TRP-KYN metabolism, prolonged life span in wild-type flies. Both inhibitors are not available for human use. Berberine, an isoquinoline alkaloid isolated from Berberis aristata, is known as the herb widely used in traditional Chinese and Indian medicine. Berberin is a strong inhibitor ...

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

    OpenAIRE

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

    2010-01-01

    A major challenge in translating the positive effects of dietary restriction (DR) for the improvement of human health is the development of therapeutic mimics. One approach to finding DR mimics is based upon identification of the proximal effectors of DR life span extension. Whole genome profiling of DR in Drosophila shows a large number of changes in gene expression, making it difficult to establish which changes are involved in life span determination as opposed to other unrelated physiolog...

  4. The Role of Culture in Social Development Over the Life Span : An Interpersonal Relations Approach

    OpenAIRE

    Albert, Isabelle; Trommsdorff, Gisela

    2014-01-01

    This article aims to illustrate the role of culture for individual development throughout the life span. First, theoretical approaches how culture affects the ontogenesis is presented, starting from early anthropological to recent eco-cultural and culture-informed approaches. Then, culture-specific conceptualizations of development over the life span are discussed, focusing on development in childhood, adolescence, adulthood, and old age. Finally, we concentrate on selected areas of social de...

  5. Copper supplementation increases yeast life span under conditions requiring respiratory metabolism

    OpenAIRE

    Kirchman, Paul A.; Botta, Gabriela

    2006-01-01

    To further exploit yeast as a model for cellular aging we have modified the replicative life span assay to force respiration, by replacing glucose with the non-fermentable carbon source glycerol. The growth rates of several different strains varied greatly, with doubling times ranging from 2.7 to 7 hours. Life spans of all strains were lower on media containing glycerol than on media containing glucose. However, supplementation of glycerol-containing media with copper resulted in increases in...

  6. An Eco-Cultural and Interpersonal Relations Approach to Development Over the Life Span

    OpenAIRE

    Trommsdorff, Gisela

    2002-01-01

    This chapter aims to illustrate the role of culture for development over the life-span. First, theoretical approaches on development in culture are presented, starting from early anthropological to recent eco-cultural approaches. Then culture-specific conceptualisations of development over the life span are discussed, including childhood, adolescence, adulthood, and old age. Finally, recent studies on subjective theories, transmissions of values, and intergenerational relations are discussed ...

  7. 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.

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

    Science.gov (United States)

    Shock, Diane Hahn

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

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

    Science.gov (United States)

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

    2013-02-15

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

  10. Chronological Changes of Quality of Life in Long-Term Survivors after Gastrectomy for Gastric Cancer

    Science.gov (United States)

    Yu, Wansik; Park, Ki Bum; Chung, Ho Young; Kwon, Oh Kyoung; Lee, Seung Soo

    2016-01-01

    Purpose A few studies have prospectively evaluated changes in quality of life (QoL) after surgery in short-term survivors; however, no prospective study has evaluated the longitudinal changes in QoL in long-terms survivors. We prospectively evaluated the chronological changes in QoL after a gastrectomy over a 5-year postoperative period in a large group of patients. Materials and Methods QoL data from the European Organization for Research and Treatment of Cancer QLQ-C30 and the QLQ-STO22 questionnaires were obtained from 254 patients who completed the entire series of QoL assessments preoperatively and at 1, 2, 3, 4, and 5 years after surgery. Results There was no statistically significant change in global health status/QoL during the 5-year postoperative period. Decreases in QoL from upper gastrointestinal symptoms including diarrhea (p physical functioning (p physical functioning, role functioning, and body image. In addition, patients should be encouraged to preserve self-esteem and maintain social activity. PMID:27004956

  11. High sexual signalling rates of young individuals predict extended life span in male Mediterranean fruit flies.

    Science.gov (United States)

    Papadopoulos, Nikos T; Katsoyannos, Byron I; Kouloussis, Nikos A; Carey, James R; Müller, Hans-Georg; Zhang, Ying

    2004-01-01

    In a laboratory study, we monitored the lifetime sexual signalling (advertisement) of wild male Mediterranean fruit flies, and we tested the hypothesis that high lifetime intensity of sexual signalling indicates high survival probabilities. Almost all males exhibited signalling and individual signalling rates were highly variable from the beginning of the adults' maturity and throughout their life span (average life span 62.3 days). Sexual signalling rates after day 10 (peak maturity) were consistently high until about 1 week before death. There was a positive relationship between daily signalling rates and life span, and an increase in signalling level by one unit over all times was associated with an approximately 50% decrease in mortality rate. Signalling rates early in adult life (day 6-20) were higher in the longest-lived than in the shortest-lived flies. These results support the hypothesis that intense sexual signalling indicates longer life span. We discuss the importance of age-specific behavioural studies for understanding the evolution of male life histories. PMID:14576929

  12. Life Span Extension in Mice by Food Restriction Depends on an Energy Imbalance12

    OpenAIRE

    Sohal, Rajindar S.; Ferguson, Melissa; Sohal, Barbara H.; Forster, Michael J.

    2009-01-01

    In this study, our main objective was to determine whether energy restriction (ER) affects the rate of oxygen consumption of mice transiently or lastingly and whether metabolic rate plays a role in the ER-related extension of life span. We compared rates of resting oxygen consumption between C57BL/6 mice, whose life span is prolonged by ER, and the DBA/2 mice where it is not, at 6 and 23 mo of age, following 40% ER for 2 and 19 mo, respectively. Mice of the 2 strains that consumed food ad lib...

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

    Science.gov (United States)

    Burns, M O; Seligman, M E

    1989-03-01

    Analyzed explanatory style across the life span. 30 Ss whose average age was 72 responded to questions about their current life and provided diaries or letters written in their youth, an average of 52 years earlier. A blind content analysis of explanatory style derived from these 2 sources revealed that explanatory style for negative events was stable throughout adult life (r = .54, p less than .002). In contrast, there appeared to be no stability of explanatory style for positive events between the same 2 time periods. These results suggest that explanatory style for negative events may persist across the life span and may constitute an enduring risk factor for depression, low achievement, and physical illness. PMID:2926642

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

    OpenAIRE

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

    2013-01-01

    Although largely unstudied, behavioral changes in decision making across the life span have implications for problems associated with poor decision making at different life stages, such as careless driving in adolescents and disadvantageous medical or financial decision making in older adults. We examine age-based differences in individual decision-making characteristics—choice consistency, rationality, and preferences for known and unknown risks—in 12- to 90-y-olds. We found that even the he...

  15. 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

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

    Science.gov (United States)

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

    2014-01-01

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

  17. 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…

  18. Small lymphocytes in peripheral lymphoid tissues of nude mice. Life-span and distribution

    DEFF Research Database (Denmark)

    Hougen, H P; Röpke, C

    1975-01-01

    far the most numerous in the lymph nodes seemed to be more sessile than para-cortical lymphocytes. The life-span of these latter cells are comparable to those of thoracic duct lymphocytes, and the scarcity of cells in the paracortex reflects the small number of recirculating lymphocytes in nude mice....

  19. Service Learning in Life-Span Developmental Psychology: Higher Exam Scores and Increased Empathy

    Science.gov (United States)

    Lundy, Brenda L.

    2007-01-01

    This article describes research conducted to evaluate the impact of service learning on exam scores and emotional empathy in a life-span development course. Service learning was 1 of 3 project options offered in the course; others included an interview project and a research paper. With the exception of the first exam, scores were significantly…

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

    Science.gov (United States)

    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…

  1. 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.

  2. Rapid growth and short life spans characterize pipefish populations in vulnerable seagrass beds.

    Science.gov (United States)

    Parkinson, K L; Booth, D J

    2016-05-01

    The life-history traits of two species of pipefish (Syngnathidae) from seagrass meadows in New South Wales, Australia, were examined to understand whether they enhance resilience to habitat degradation. The spotted pipefish Stigmatopora argus and wide-bodied pipefish Stigmatopora nigra exhibit some of the shortest life spans known for vertebrates (longevity up to 150 days) and rapid maturity (male S. argus 35 days after hatching (DAH) and male S. nigra at 16-19 DAH), key characteristics of opportunistic species. Growth rates of both species were extremely rapid (up to 2 mm day(-1) ), with seasonal and sex differences in growth rate. It is argued that short life spans and high growth rates may be advantageous for these species, which inhabit one of the most threatened marine ecosystems on earth. PMID:27005315

  3. How does personality develop over the life-course: Results of the Brno Longitudinal Study on Life-Span Development

    Czech Academy of Sciences Publication Activity Database

    Blatný, Marek; Jelínek, Martin; Osecká, Terezie

    New York: Nova Science Publishers, 2009 - (Elling, L.), s. 213-245 ISBN 978-1-60741-612-8 Institutional research plan: CEZ:AV0Z70250504 Keywords : life-span development * personality stability and change * longitudinal study Subject RIV: AN - Psychology

  4. 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.

  5. [Life span and cercaria shedding of schistosome-infected snails in mountain region of Yunnan].

    Science.gov (United States)

    Xie, F; Yin, G; Wu, J; Duan, Y; Zhang, X; Yang, J; Qian, K; Tan, H; Zheng, J; Zhang, R

    1990-01-01

    The life span and cercaria shedding of infected Oncomelania snails in a mountain region of Shitoudi village, Weishan County, Yunnan Province were observed in simulated local ecological environments. 135 infected snails were isolated for observation 3 months after exposure to miracidia in August, 1987. The snail survival rate from the day of initial cercaria shedding to next June, July, August and September was 27.4, 16.3, 13.3 and 11.9% respectively, and the average number of cercariae shed was 139.9, 29.6, 39.2 and 75 per month respectively. The average life span of infected snails was 171.6 days. The average number of cercariae shed per snail in its whole life was 673.0. It was estimated that the average patent period of infected snails was over half a year. As this is the first report in our country in respect to the life span and cercariae shedding of infected snails in a mountain region, the result might be useful for quantitative analysis of epidemiological factors of schistosomiasis in this kind of endemic areas as well as for formulation of control strategy. PMID:2114229

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

    Science.gov (United States)

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

    2016-06-17

    Adult stem cells (SCs) are essential for tissue maintenance and regeneration yet are susceptible to senescence during aging. We demonstrate the importance of the amount of the oxidized form of cellular nicotinamide adenine dinucleotide (NAD(+)) and its effect on mitochondrial activity as a pivotal switch to modulate muscle SC (MuSC) senescence. Treatment with the NAD(+) precursor nicotinamide riboside (NR) induced the mitochondrial unfolded protein response and synthesis of prohibitin proteins, and this rejuvenated MuSCs in aged mice. NR also prevented MuSC senescence in the mdx (C57BL/10ScSn-Dmd(mdx)/J) mouse model of muscular dystrophy. We furthermore demonstrate that NR delays senescence of neural SCs and melanocyte SCs and increases mouse life span. Strategies that conserve cellular NAD(+) may reprogram dysfunctional SCs and improve life span in mammals. PMID:27127236

  7. 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. PMID:23528790

  8. ETS-4 Is a Transcriptional Regulator of Life Span in Caenorhabditis elegans

    OpenAIRE

    Thyagarajan, Bargavi; Blaszczak, Adam G.; Chandler, Katherine J.; Watts, Jennifer L; Johnson, W. Evan; Graves, Barbara J.

    2010-01-01

    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 wor...

  9. The Mother Enrichment Program: A Genetic System for Facile Replicative Life Span Analysis in Saccharomyces cerevisiae

    OpenAIRE

    Lindstrom, Derek L.; Gottschling, Daniel E.

    2009-01-01

    The replicative life span (RLS) of Saccharomyces cerevisiae has been established as a model for the genetic regulation of longevity despite the inherent difficulty of the RLS assay, which requires separation of mother and daughter cells by micromanipulation after every division. Here we present the mother enrichment program (MEP), an inducible genetic system in which mother cells maintain a normal RLS—a median of 36 generations in the diploid MEP strain—while the proliferative potential of da...

  10. Estimates for the number of visible galaxy-spanning civilizations and the cosmological expansion of life

    OpenAIRE

    Olson, S. Jay

    2015-01-01

    If advanced civilizations appear in the universe with an ability and desire to expand, the entire universe can become saturated with life on a short timescale, even if such expanders appear rarely. Our presence in an apparently untouched Milky Way thus constrains the appearance rate of galaxy-spanning Kardashev type III (K3) civilizations, if it is assumed that some fraction of K3 civilizations will continue their expansion at intergalactic distances. We use this constraint to estimate the ap...

  11. Toxicity of cadmium and zinc mixtures to the decaudized cercarial life span of Diplostomum spathaceum

    OpenAIRE

    Morley, Neil; Crane, M.; Lewis, J W

    2005-01-01

    The effects of cadmium and zinc mixtures at concentrations ranging from 0.1 to 10,000mg l21 on the life-span of decaudized cercarial bodies (cercariae that have shed their tails) of Diplostomum spathaceum (Trematoda: Diplostomatidae) was investigated. Cercariae were exposed to metal mixtures of equal and unequal concentrations, and a low-dose pre-treatment followed by a high-dose exposure mixtures. Metal mixtures demonstrated variable effects on decaudized cercariae either by increasing or re...

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

    International Nuclear Information System (INIS)

    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

  13. Induced overexpression of mitochondrial Mn-superoxide dismutase extends the life span of adult Drosophila melanogaster.

    OpenAIRE

    Sun, Jingtao; Folk, Donna; Bradley, Timothy J.; Tower, John

    2002-01-01

    A transgenic system ("FLP-out") based on yeast FLP recombinase allowed induced overexpression of MnSOD enzyme in adult Drosophila melanogaster. With FLP-out a brief heat pulse (HP) of young, adult flies triggered the rearrangement and subsequent expression of a MnSOD transgene throughout the adult life span. Control (no HP) and overexpressing (HP) flies had identical genetic backgrounds. The amount of MnSOD enzyme overexpression achieved varied among six independent transgenic lines, with inc...

  14. A method for describing disease patterns during the life span of dairy cows

    OpenAIRE

    Faye, Bernard; Boulme, R; Lescourret, Francoise; Coulon, Jean Baptiste

    1996-01-01

    This study presents some guidelines for describing the health status of dairy cows over their entire life span. It aims to define some types of health-paths (trajectories) described in terms of disease patterns (at the lactation level) and related to cow characteristics (breed, production potential) and farms. The data were collected over a 20-year period on three experimental farms. Eight diseases were analysed: clinical mastitis, lameness, placental retention, foot rot, digestive disorders,...

  15. Plasticity of Executive Control Induced by Process-Based Cognitive Training Across the Life-Span

    OpenAIRE

    Zinke, Katharina

    2012-01-01

    Plasticity is a central concept within the life-span approach of development and is defined as the ability of an individual to change and reorganize in response to environmental challenges (e.g., Baltes & Singer, 20019. Such intraindividual changes can be induced by systematic cognitive training. Recent studies suggest that substantial amounts of plasticity can be induced in executive control functions with a process-based training approach. These newer studies show that repeated practice on ...

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

    Institute of Scientific and Technical Information of China (English)

    Indrikis KRAMS; Jan(i)na DAUK(S)TE; Inese KIVLENIECE; Ants KAASIK; Tatjana KRAMA; Todd M.FREEBERG; Markus J.RANTALA

    2013-01-01

    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.

  17. 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].

  18. Life span, reproductive output, and reproductive opportunity in captive Goeldi's monkeys (Callimico goeldii).

    Science.gov (United States)

    Nuss, Kara; Warneke, Mark

    2010-01-01

    In the absence of long-term field studies, demographic and reproductive records from animals housed in zoos and research laboratories are a valuable tool for the study of life history variables relating to reproduction. In this study, we analyzed studbook records of more than 2,000 individuals born over a 40-year period (1965-2004) to describe life history patterns of captive Goeldi's monkeys (Callimico goeldii) housed in North America and Europe. Using Kaplan-Meier survival analysis methods, we found the mean life span to be 5.5 years. The rate of infant mortality, defined as death before 30 days, was approximately 30%, with European animals being more likely to survive infancy than North American animals. When individuals surviving at least 1.5 years are considered, lifetime reproductive output averaged 3.5 offspring, yet more than one-third of individuals did not produce any offspring. Using a smaller dataset of individuals with known pairing histories, we developed a measure of opportunity for reproduction (OFR), which represented the total time an individual was known to be housed with a potential mate. For both sexes, we found that the correlation between OFR and number of offspring produced was much higher than the correlation between life span and number of offspring produced. This result highlights the importance of taking into account an individual's OFR. As a whole, our findings help characterize the life histories of captive Goeldi's monkeys and emphasize the impact management practices may have on reproductive success. PMID:20131357

  19. Life span of C57 mice as influenced by radiation dose, dose rate, and age at exposure

    International Nuclear Information System (INIS)

    This study was designed to measure the life shortening of C57BL/6J male mice as a result of exposure to five external doses from 60Co gamma radiation delivered at six different dose rates. Total doses ranged from 20 to 1620 rad at exposure rates ranging from 0.7 to 36,000 R/day. The ages of the mice at exposure were newborn, 2, 6, or 15 months. Two replications were completed. Although death was the primary endpoint, we did perform gross necropsies. The life span findings are variable, but we found no consistent shortening compared to control life spans. Therefore, we cannot logically extrapolate life shortening to lower doses, from the data we have obtained. In general, the younger the animals were at the beginning of exposure, the longer their life spans were compared to those of controls. This relationship weakened at the higher doses and dose rates, as mice in these categories tended not to have significantly different life spans from controls. Using life span as a criterion, we find this study suggests that some threshold dosage may exist beyond which effects of external irradiation may be manifested. Up to this threshold, there is no shortening effect on life span compared to that of control mice. Our results are in general agreement with the results of other researchers investigating human and other animal life span effects on irradiation

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

    Science.gov (United States)

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

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

  1. Dead or alive: deformed wing virus and Varroa destructor reduce the life span of winter honeybees.

    Science.gov (United States)

    Dainat, Benjamin; Evans, Jay D; Chen, Yan Ping; Gauthier, Laurent; Neumann, Peter

    2012-02-01

    Elevated winter losses of managed honeybee colonies are a major concern, but the underlying mechanisms remain controversial. Among the suspects are the parasitic mite Varroa destructor, the microsporidian Nosema ceranae, and associated viruses. Here we hypothesize that pathogens reduce the life expectancy of winter bees, thereby constituting a proximate mechanism for colony losses. A monitoring of colonies was performed over 6 months in Switzerland from summer 2007 to winter 2007/2008. Individual dead workers were collected daily and quantitatively analyzed for deformed wing virus (DWV), acute bee paralysis virus (ABPV), N. ceranae, and expression levels of the vitellogenin gene as a biomarker for honeybee longevity. Workers from colonies that failed to survive winter had a reduced life span beginning in late fall, were more likely to be infected with DWV, and had higher DWV loads. Colony levels of infection with the parasitic mite Varroa destructor and individual infections with DWV were also associated with reduced honeybee life expectancy. In sharp contrast, the level of N. ceranae infection was not correlated with longevity. In addition, vitellogenin gene expression was significantly positively correlated with ABPV and N. ceranae loads. The findings strongly suggest that V. destructor and DWV (but neither N. ceranae nor ABPV) reduce the life span of winter bees, thereby constituting a parsimonious possible mechanism for honeybee colony losses. PMID:22179240

  2. 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. PMID:19485668

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

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Vradi, Eleni; McIntyre, Roger S; Andersen, Per Kragh

    2015-01-01

    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......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......, 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...

  4. Hippocampal volume varies with educational attainment across the life-span

    Directory of Open Access Journals (Sweden)

    Kimberly G. Noble

    2012-11-01

    Full Text Available Socioeconomic disparities – and particularly differences in educational attainment – are associated with remarkable differences in cognition and behavior across the life-span. Decreased educational attainment has been linked to increased exposure to life stressors, which in turn have been associated with structural differences in the hippocampus and the amygdala. However, the degree to which educational attainment is directly associated with anatomical differences in these structures remains unclear. Recent studies in children have found socioeconomic differences in regional brain volume in the hippocampus and amygdala across childhood and adolescence. Here we expand on this work, by investigating whether disparities in hippocampal and amygdala volume persist across the life-span. In a sample of 275 individuals from the BRAINnet Foundation database ranging in age from 17 to 87, we found that socioeconomic status, as operationalized by years of educational attainment, moderates the effect of age on hippocampal volume. Specifically, hippocampal volume tended to markedly decrease with age among less educated individuals, whereas age-related reductions in hippocampal volume were less pronounced among more highly educated individuals. No such effects were found for amygdala volume. Possible mechanisms by which education may buffer age-related effects on hippocampal volume are discussed.

  5. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Stampfer, Martha R.; Garbe, James C.

    2016-06-28

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

  7. [Effect of epitalon and melatonin on life span and spontaneous carcinogenesis in senescence accelerated mice (SAM)].

    Science.gov (United States)

    Anisimov, V N; Popovich, I G; Zabezhinskiĭ, M A; Rozenfel'd, S V; Khavinson, V Kh; Semenchenko, A V; Iashin, A I

    2005-01-01

    Female senescence accelerated mice SAMP-1. (prone) and SAMR-1 (resistant) were exposed 5 times a week monthly to melatonin (with drinking water 20mg/ml during the night hours) or to s.c. injections of epitalon (Ala-Glu-Asp-Gly) at a single dose 1mkg/mouse. Control mice were intact or exposed to injection of 0.1 ml normal saline. The body weight and temperature, food consumption, estrous function were monitored regularly. The life span and tumor incidence were evaluated as well. As age advanced, the weight increased whereas food consumption and body temperature did not change. There was no significant substrain difference in these parameters. Exposure to melatonin or epitalon also failed to influence those indices. As age advanced, the incidence of irregular estrous cycles increased both in SAMP-1 and SAMR-1, whereas the treatment with both melatonin and epitalon prevented such disturbances. SAMP-1 revealed some features of accelerated aging as compared to SAMR-1. The mean life span of the 10% of the last survivors among treated SAMP-1 was shorter than that of SAMR-1, aging rate increased and mortality doubling time decreased. There was a direct correlation between body mass of the two substrains at the age of 3 and 12 months matched by body mass increase and longer life span. Melatonin or epitalon treatment was followed by longer mean and maximum survival in the 10% of the last survivors among SAMP-1. Melatonin involved decreased aging rate and increased mortality doubling time. Malignant lymphomas predominated in SAM without any significant difference in frequency between the substrains. While melatonin failed to influence tumor incidence or term of detection in SAMP-1, neither did epitalon affect frequency. However, it was followed by longer survival in tumor-free animals. No link between melatonin or epitalon treatment, on the one hand, and carcinogenesis, on the other, was reported in SAMR-1. PMID:15909815

  8. Resilience, according to the paradigm of the development along the life (life-span

    Directory of Open Access Journals (Sweden)

    Arlete Portella Fontes

    2010-10-01

    Full Text Available Resilience, in the approach of the development along the life, refers to the capacity of recovering and maintenance of the adaptive behavior when the person feels threatened by any distressing event (Staudinger, Marsiske and Baltes, 1995. Although the losses become more likely than the developed gains, the aged people can present considerable stability, self-esteem, competence, self-efficacy, subjective quality of life. The resilience is based on active protecting resources along the life: mechanisms of self-regulation, self-efficacy, emotional regulation, mechanisms of stress oping, selection strategies, optimization and compensation of the domains of human functioning. At the end of the article, interventions to increase the resilience of the aged are suggested.

  9. Super's Life-Span, Life-Space Approach and Its Outlook for Refinement.

    Science.gov (United States)

    Herr, Edwin L.

    1997-01-01

    Describes the major elements of a lifespan, life-space approach to career development. Looks at the origins of these elements and briefly describes their evolution. Suggests five categories of possible future refinements in this approach so as to enhance theory building, testing, and synthesizing this model's applicability. (RJM)

  10. 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: 4.777, year: 2014

  11. 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 PMID:27560768

  12. 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...

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

    International Nuclear Information System (INIS)

    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 239PuO2. Exposure of beagles currently on study was initiated in 1970 with 239PuO2, in 1973 with 238PuO2, and in 1976 with 239Pu(NO3)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 239PuO2 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

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

    Science.gov (United States)

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

    2015-07-01

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

  15. Analysis of neoplasia in life-span radiation effects studies in animals

    International Nuclear Information System (INIS)

    Analysis of the occurrence of neoplastic disease in animals on life-span radiation effects experiments presents some unique problems. A simple analysis of tumor incidence or prevalence may overlook differences in the nature of specific types of neoplasms which can be extremely important in interpreting the results. Analyses should address not only whether or not an animal has a particular tumor type, but should also address the ultimate effect of that tumor on the fate of the animal. For life-span studies in dogs, where multiple neoplasms in individual animals are the rule rather than the exception this is particularly important. An easily computerized approach to performing such analyses has been adapted from a previous work. Neoplasms are classified as incidental (those found at necropsy in dogs which died of an unrelated cause), mortality-independent (those seen in live dogs and diagnosed after surgical removal), or fatal (those directly or indirectly responsible for death). In the authors' studies such categorization has allowed the evaluation of the overall impact of a tumor on an animal and enhanced the understanding of the meaning of experimental results. Adoption of a similar approach by various groups performing radiation effects studies in animals would facilitate the comparative evaluation of data from these studies

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

    Science.gov (United States)

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

    2015-06-01

    Studies using different organisms revealed that reducing calorie intake, without malnutrition, known as calorie restriction (CR), increases life span, but its mechanism is still unkown. Using the yeast Saccharomyces cerevisiae as eukaryotic model, we observed that Cu, Zn-superoxide dismutase (Sod1p) is required to increase longevity, as well as to confer protection against lipid and protein oxidation under CR. Old cells of sod1 strain also presented a premature induction of apoptosis. However, when CTT1 (which codes for cytosolic catalase) was overexpressed, sod1 and WT strains showed similar survival rates. Furthermore, CTT1 overexpression decreased lipid peroxidation and delayed the induction of apoptotic process. Superoxide is rapidly converted to hydrogen peroxide by superoxide dismutase, but it also undergoes spontaneous dismutation albeit at a slower rate. However, the quantity of peroxide produced from superoxide in this way is two-fold higher. Peroxide degradation, catalyzed by catalase, is of vital importance, because in the presence of a reducer transition metal peroxide is reduced to the highly reactive hydroxyl radical, which reacts indiscriminately with most cellular constituents. These findings might explain why overexpression of catalase was able to overcome the deficiency of Sod1p, increasing life span in response to CR. PMID:25573485

  17. Life span and tumorigenesis in mice exposed to continuous low dose-rate γ-rays

    International Nuclear Information System (INIS)

    To evaluate late biological effects of chronic low dose-rate radiation, we are conducting two experiments. Experiment 1 - Late effects of chronic low dose-rate γ-rays irradiation on SPF mice, using life-span and pathological changes as parameters. Continuous irradiation with γ-rays for 400 days was performed using 137Cs γ-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 they died a natural death. Statistical analyses show that the life spans of both sexes irradiated at 20mGy/day (p<0.0001) and of females irradiated at 1 mGy/day (p<0.05) were significantly shorter than that of the control group. Partial results show that the most common lethal neoplasms in the pooled data of non-irradiated control and irradiated make mice, in order of frequency, were neoplasms of the lymphohematopoietic system, liver, and lung. In female mice, neoplasms of the lymphohematopoietic system and soft tissue were common. Experiment 2 - Effects on the progeny of chronic low dose-rate γ-ray irradiated SPF mice: pilot study, was started in 1999 and is currently in progress. (author)

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

    International Nuclear Information System (INIS)

    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

  19. Comparative transcriptional pathway bioinformatic analysis of dietary restriction, Sir2, p53 and resveratrol life span extension in Drosophila

    OpenAIRE

    Antosh, Michael; Whitaker, Rachel; Kroll, Adam; Hosier, Suzanne; Chang, Chengyi; Bauer, Johannes; Cooper, Leon; Neretti, Nicola; HELFAND, STEPHEN L.

    2011-01-01

    A multiple comparison approach using whole genome transcriptional arrays was used to identify genes and pathways involved in calorie restriction/dietary restriction (DR) life span extension in Drosophila. Starting with a gene centric analysis comparing the changes in common between DR and two DR related molecular genetic life span extending manipulations, Sir2 and p53, lead to a molecular confirmation of Sir2 and p53's similarity with DR and the identification of a small set of commonly regul...

  20. 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

  1. Potentially Traumatic Events at Different Points in the Life Span and Mental Health: Findings From SHARE-Israel

    OpenAIRE

    Shrira, Amit; Shmotkin, Dov; Litwin, Howard

    2012-01-01

    This study addressed the association between adversity cumulated at different points in the life span and present mental health. Data of 1,130 participants aged 50+ were drawn from the Israeli component of the Survey of Health, Ageing and Retirement in Europe (SHARE). Measures included an inventory of potentially traumatic events, mental distress (depressive symptoms), and well-being (quality of life, life satisfaction). Adversity reported to have occurred early in life was positively related...

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

    Science.gov (United States)

    Strait, Dana L; Kraus, Nina

    2014-02-01

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

  3. Estimates for the number of visible galaxy-spanning civilizations and the cosmological expansion of life

    CERN Document Server

    Olson, S Jay

    2015-01-01

    If advanced civilizations appear in the universe with a desire to expand, the entire universe can become saturated with life on a short timescale, even if such expanders appear but rarely. Our presence in an untouched Milky Way thus constrains the appearance rate of galaxy-spanning Kardashev type III (K3) civilizations, if it is assumed that some fraction of K3 civilizations will continue their expansion at intergalactic distances. We use this constraint to estimate the appearance rate of K3 civilizations for 81 cosmological scenarios by specifying the extent to which humanity could be a statistical outlier. We find that in nearly all plausible scenarios, the distance to the nearest visible K3 is cosmological. In searches where the observable range is limited, we also find that the most likely detections tend to be expanding civilizations who have entered the observable range from farther away. An observation of K3 clusters is thus more likely than isolated K3 galaxies.

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

    Science.gov (United States)

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

    2013-03-15

    The Life Span Study is a long-term epidemiologic cohort study of survivors of the atomic bombs dropped on Hiroshima and Nagasaki, Japan. In this issue of the Journal, Richardson et al. (Am J Epidemiol. 2013;177(6):562-568) suggest that those who died in the earliest years of follow-up were more likely to have a missing dose of radiation exposure assigned, leading to a bias in the radiation risk estimates. We show that nearly all members of the cohort had shielding information recorded before the beginning of follow-up and that much of the alleged bias that Richardson et al. describe simply reflects the geographic distribution of shielding conditions for which reliable dosimetry was impossible. PMID:23429724

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

    International Nuclear Information System (INIS)

    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. Application of 51Cr-RBC life span study and surface counting in blood diseases

    International Nuclear Information System (INIS)

    Present article summarized the RBC life span and liver, spleen surface counting in 274 cases of blood diseases. Whole blood labelling of 51Cr labelled auto or normal O type blood was used. The results showed that there was a shortening of the apparent survival time with different magnitude in various blood diseases, therefore it can be used for understanding the severity of hemolytic anemia, detection of latent hemolysis and also the investigation of the destruction and survival of RBC in other blood diseases. The surface counting of spleen, liver and precordium denoted that the S/P, S/L ratio was highest in hyperspleenism, consecutively various hemolytic anemia and cirrhosis of liver, hence this test can be used as an indication for splenectomy

  7. Neuromodulation of associative and organizational plasticity across the life span: empirical evidence and neurocomputational modeling.

    Science.gov (United States)

    Li, Shu-Chen; Brehmer, Yvonne; Shing, Yee Lee; Werkle-Bergner, Markus; Lindenberger, Ulman

    2006-01-01

    Developmental plasticity is the key mechanism that allows humans and other organisms to modify and adapt to contextual and experiential influences. Thus, reciprocal co-constructive interactions between behavioral and neuronal plasticity play important roles in regulating neurobehavioral development across the life span. This review focuses on behavioral and neuronal evidence of lifespan differences in associative memory plasticity and plasticity of the functional organization of cognitive and cortical processes, as well as the role of the dopaminergic system in modulating such plasticity. Special attention is given to neurocomputational models that help exploring lifespan differences in neuromodulation of neuronal and behavioral plasticity. Simulation results from these models suggest that lifespan changes in the efficacy of neuromodulatory mechanisms may shape associative memory plasticity and the functional organization of neurocognitive processes by affecting the fidelity of neuronal signal transmission, which has consequences for the distinctiveness of neurocognitive representations and the efficacy of distributed neural coding. PMID:16930705

  8. 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.

  9. 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. PMID:26816517

  10. 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.

  11. Life-span studies on mice exposed to heavy charged particles or photons

    International Nuclear Information System (INIS)

    The carcinogenic risk associated with heavy charged (HZE) particles is currently undefined. Precise relationships have been established for relative biological effectiveness (RBE) and linear energy transfer (LET) for the killing of cells in vitro and for other short-term (acute) biological responses to charged particles, but comparable information is lacking on carcinogenic response. Experiments are in progress to study induction/promotion of Harderian gland tumors, and the present life-span studies should provide complementary information because it is inferred that over the dose range explored in the present experiments, most of the life shortening is attributable to induction/promotion of neoplastic diseases. The information sought is important both for understanding fundamental mechanisms of radiation carcinogenesis and for assessing the risk of the space radiation environment and of radiation therapy or other medical applications of heavy charged particles in young patients whose life expectancy could permit expression of a tumor. The hypothesis tested in the core experiment, designated SKYHOOK, is that LET dependence for life shortening and excess mortality rates observed after mice are exposed to heavy charged particles (HZE) will conform to existing theory and observations based on other endpoints; namely, a peak RBE at a dose-averaged LET value of approximately 100 keV/μm, with RBE diminishing at lesser and greater values of LET. Because results on cell killing show different RBE values, at the same approximate LET, for different charged particles, the possibility exists that LET by itself is not a fully adequate descriptor for biological response, and physical characteristics such as mass, charge, or velocity may also be of great importance

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

    Science.gov (United States)

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

    1990-08-01

    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. PMID:2366300

  13. 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. PMID:25791963

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

    International Nuclear Information System (INIS)

    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. Stability and Change in Affective Experience across the Adult Life-Span: Analyses with a National Sample from Germany

    OpenAIRE

    Kunzmann, Ute; Richter, David; Schmukle, Stefan C.

    2013-01-01

    Using cross-sectional and longitudinal data from a national sample spanning the adult life span, age differences in anger and sadness were explored. The cross-sectional and longitudinal findings consistently suggest that the frequency of anger increases during young adulthood, but then shows a steady decrease until old age. By contrast, the frequency of sadness remains stable over most of adulthood and begins to increase in old age. In addition, the effects of age on happiness were investigat...

  16. Sex-specific Tradeoffs With Growth and Fitness Following Life-span Extension by Rapamycin in an Outcrossing Nematode, Caenorhabditis remanei.

    Science.gov (United States)

    Lind, Martin I; Zwoinska, Martyna K; Meurling, Sara; Carlsson, Hanne; Maklakov, Alexei A

    2016-07-01

    Rapamycin inhibits the nutrient-sensing TOR pathway and extends life span in a wide range of organisms. Although life-span extension usually differs between the sexes, the reason for this is poorly understood. Because TOR influences growth, rapamycin likely affects life-history traits such as growth and reproduction. Sexes have different life-history strategies, and theory predicts that they will resolve the tradeoffs between growth, reproduction, and life span differently. Specifically, in taxa with female-biased sexual size dimorphism, reduced growth may have smaller effects on male fitness. We investigated the effects of juvenile, adult, or life-long rapamycin treatment on growth, reproduction, life span, and individual fitness in the outcrossing nematode Caenorhabditis remanei Life-long exposure to rapamycin always resulted in the strongest response, whereas postreproductive exposure did not affect life span. Although rapamycin resulted in longer life span and smaller size in males, male individual fitness was not affected. In contrast, size and fitness were negatively affected in females, whereas life span was only extended under high rapamycin concentrations. Our results support the hypothesis that rapamycin affects key life-history traits in a sex-specific manner. We argue that the fitness cost of life-span extension will be sex specific and propose that the smaller sex generally pay less while enjoying stronger life-span increase. PMID:26472877

  17. [Information theory of ageing: studying the effect of bone marrow transplantation on the life span of mice].

    Science.gov (United States)

    Karnaukhov, A V; Karnaukhova, E V; Sergievich, L A; Karnaukhova, N A; Karnaukhova, N A; Bogdanenko, E V; Smirnov, A A; Manokhina, I A; Karnaukhov, V N

    2014-01-01

    In this paper the method of life span extension of multicellular organisms (human) using the reservation of stem cells followed by autotransplantation has been proposed. As the efficiency of this method results from the information theory of ageing, it is important to verify it experimentally testing the basic concepts of the theory. Taking it into consideration, the experiment on the bone marrow transplantation to old mice from young closely-related donors of the inbred line was carried out. It has been shown, that transplanted animals exhibited a survival advantage, a mean life span increased by 34% as compared to the control. This result not only demonstrates the efficiency of the proposed method for life span extension of multicellular organisms, but also confirms the basis of the information theory of ageing. PMID:25707248

  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)

    It is established that life span and mortality pattern of animals subjected to chronic intake of 90Sr, 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 90Sr(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. Investigating the life-span of cork products for household and personal use through a longitudinal approach with users

    OpenAIRE

    Pereira, Ana Carina da Silva

    2014-01-01

    Doutoramento em Engenharia do Ambiente - Instituto Superior de Agronomia Products with a long life-span are important to reduce resources consumption and outflows to the environment. Cork has an interesting eco-profile since it is a natural non-wood forest product that can be produced without endangering the cork oak vitality. The aim of the work is to investigate the life-span of cork products. A total of 18 different cork products including household and personal use products were studie...

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

    International Nuclear Information System (INIS)

    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

  1. 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. PMID:26432533

  2. 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.

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

    International Nuclear Information System (INIS)

    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)

  4. 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. PMID:25870404

  5. β-N-Methylamino-L-Alanine Induces Neurological Deficits and Shortened Life Span in Drosophila

    Directory of Open Access Journals (Sweden)

    R. Grace Zhai

    2010-11-01

    Full Text Available 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.

  6. 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. PMID:27481911

  7. Human-figure drawing and memory functioning across the adult life span.

    Science.gov (United States)

    Ericsson, K; Winblad, B; Nilsson, L -G.

    2001-03-01

    The main objective was to evaluate changes in the ability to draw the human figure (HFD) across adult life span and to relate these changes to those known to exist in memory function. Healthy adults (1000) from each of 10 five-year cohorts between 35 and 80 years were recruited randomly from a population in northern Sweden. Each participant was administered a health examination including cognitive testing and a drawing test, and an extensive examination of memory functions. For the drawing variables HFDarch and HFDtot, there is a steady decrease in episodic memory with poor drawers performing at a lower level. For semantic memory up to 65 years of age, there is no difference in performance, but thereafter a decrease. Good drawers show a better memory performance than poor drawers. For priming data for both HFDarch and HFDtot, there seems to be an interaction between age and drawing, such that poor drawers perform at a lower level for the two oldest groups but not for the youngest group. The HFDess is a valuable instrument and can support clinical evaluation as a screening for cognitive decline. The reduction of essential body details was strongly related to dementia progression, and thus as good a predictor of cognitive decline as episodic memory performance. The reduced capacity to perform a complex HFD declines with age and is most pronounced in the oldest age groups. PMID:11313105

  8. Atomic Bomb Survivors Life-Span Study: Insufficient Statistical Power to Select Radiation Carcinogenesis Model.

    Science.gov (United States)

    Socol, Yehoshua; Dobrzyński, Ludwik

    2015-01-01

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

  9. [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. PMID:27476265

  10. Entropy Stress and Scaling of Vital Organs over Life Span Based on Allometric Laws

    Directory of Open Access Journals (Sweden)

    Carlos Silva

    2012-12-01

    Full Text Available Abstract: Past theories on total lifetime energy expenditures and entropy generation in biological systems (BS dealt with whole systems, but the recent literature suggests that the total metabolic rate of a BS,q̇body (W is a sum of product of specific metabolic rate q̇k,m (W/kg of organ k of each vital life organ, k {k = brain, heart, kidney and liver, or abbreviated as BHKL, and rest of the organ mass (R} and mass of each organ k (mk. Using this hypothesis, Kleiber’s law on metabolic rate of BS (q̇body for animals of different sizes was validated. In this work, a similar procedure is adopted in estimating total entropy generation rate of whole human body (σ̇body, W/K as a sum of product of specific entropy generation rate for each organ, σ̇k,m (W/{K kg of organ k·} and the organ mass at any given age (t. Further integrating over life span for each organ (tlife, the lifetime specific entropy generated by organ k, σk,m,life (J of organ k/ {K kg organ k} is calculated. Then lifetime entropy generation of unit body mass, σbody,M,life (J/{K kg body mass·} is calculated as a sum of the corresponding values contributed by all vital organs to unit body mass and verified with previously published literature. The higher the σk,m,life , the higher the entropy stress level (which is a measure of energy released by unit organ mass of k as heat and the irreversibility within the organ, resulting in faster degradation of organ and the consequent health problems for the whole BS. In order to estimate σ̇k (W/K of organ k, data on energy release rate (q̇ is needed over lifetime for each organ. While the Adequate Macronutrients Distribution Range (AMDR/Adequate Intake (AI publication can be used in estimating the energy intake of whole body vs. age for the human body, the energy expenditure data is not available at organ level. Hence the σk,m,life was computed using existing allometric laws developed for the metabolism of the organs, the

  11. Estimating age-dependent costs and benefits of roots with contrasting life span: comparing apples and oranges

    NARCIS (Netherlands)

    Bouma, T.J.; Yanai, R.D.; Elkin, A.D.; Hartmond, U.; Flores-Alva, D.E.; Eissenstat, D.M.

    2001-01-01

    The relation between root age and root function is poorly understood, despite its importance to root longevity. The effect of root age on respiration rates and P-32-uptake kinetics was determined for roots excavated from mature apple and citrus trees (median root life spans of 30 vs 300 d). To evalu

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

    International Nuclear Information System (INIS)

    The dependency of the beagle-dog life span on level of and age at exposure to 60Co 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

  13. Osteopenia is present at an early age and worsens across the life span in girls and women with Rett syndrome

    Science.gov (United States)

    Girls and women with Rett syndrome (RTT) are at increased risk for osteopenia and skeletal fractures. Our objective was to characterize the natural history of bone mineralization in RTT girls and women across their life span and to identify genetic, nutritional, physical, hormonal, or inflammatory ...

  14. 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…

  15. Missing doses in the life span study of Japanese atomic bomb survivors.

    Science.gov (United States)

    Richardson, David B; Wing, Steve; Cole, Stephen R

    2013-03-15

    The Life Span Study of atomic bomb survivors is an important source of risk estimates used to inform radiation protection and compensation. Interviews with survivors in the 1950s and 1960s provided information needed to estimate radiation doses for survivors proximal to ground zero. Because of a lack of interview or the complexity of shielding, doses are missing for 7,058 of the 68,119 proximal survivors. Recent analyses excluded people with missing doses, and despite the protracted collection of interview information necessary to estimate some survivors' doses, defined start of follow-up as October 1, 1950, for everyone. We describe the prevalence of missing doses and its association with mortality, distance from hypocenter, city, age, and sex. Missing doses were more common among Nagasaki residents than among Hiroshima residents (prevalence ratio = 2.05; 95% confidence interval: 1.96, 2.14), among people who were closer to ground zero than among those who were far from it, among people who were younger at enrollment than among those who were older, and among males than among females (prevalence ratio = 1.22; 95% confidence interval: 1.17, 1.28). Missing dose was associated with all-cancer and leukemia mortality, particularly during the first years of follow-up (all-cancer rate ratio = 2.16, 95% confidence interval: 1.51, 3.08; and leukemia rate ratio = 4.28, 95% confidence interval: 1.72, 10.67). Accounting for missing dose and late entry should reduce bias in estimated dose-mortality associations. PMID:23429722

  16. Atomic bomb dosimetry systems for life span study in Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    The Life Span Study (LSS) of the atomic bomb survivors in Hiroshima and Nagasaki has provided invaluable qualitative data on the late effects of ionizing radiations to human beings. For the study, the best possible estimates of the atomic bomb radiations received by the organs or tissues of survivors were principally required. The first dose estimates for the survivors were designated as Tentative 1957 Doses (T57D). In 1965, a revised dosimetry system was constructed on the basis of experimental data from a field measurement with the Health Physics Research Reactor (HPRR) at Nevada and from the thermoluminescence measurements of ceramic material and the radioactivity measurements of iron materials in Japan. These dose estimates were designated as Tentative 1965 (T65D). The T65D system was used with a great deal of confidence for risk assessment throughout the 1970s. In 1980, however, two scientific groups in the United States challenged the validity of the T65D system. In the fall of 1981, a Working Group on Atomic Bomb Dosimetry Reassessment was organized both in the United States and in Japan. After four US-Japan Joint Workshops for Reassessment of Atomic Bomb Radiation Dosimetry, the new dosimetry system which is designated as Dosimetry System 1986 (DS86) was constructed. Recently, the Radiation Effects Research Foundation (RERF) has published the results of LSS which focussed on a comparison of the radiation-related risks of site-specific cancer mortality based on the DS86 and the T65D and deaths from cancer in the years 1950 to 1985. The International Commission on Radiological Protection (ICRP) has issued its basic recommendations as ICRP Publication 60 including the revised dose limits in occupational exposures. This paper reviews the dosimetry system of survivors for the LSS and discusses the physical basis for the DS86. (author)

  17. Implicit Motor Sequence Learning and Working Memory Performance Changes Across the Adult Life Span.

    Science.gov (United States)

    Meissner, Sarah Nadine; Keitel, Ariane; Südmeyer, Martin; Pollok, Bettina

    2016-01-01

    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 (SRTT). 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. PMID:27199736

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

    International Nuclear Information System (INIS)

    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

  19. The effect of UV irradiation on proliferation and life span of human diploid fibroblast-like cells

    International Nuclear Information System (INIS)

    The effect of low dose UV irradiation on the reinitiation of proliferative activity and on the life span of human diploid fibroblast-like cells is described. Cells were exposed to UV at confluence or after maintenance in an arrested state. Cell division was stimulated immediately after UV irradiation or after an additional post-UV incubation period. Arrested populations of all in vitro ages exhibited a greater sensitivity to UV and the reinitiation of proliferation was enhanced by post-UV incubation before stimulation. Ultraviolet light had no effect on life span regardless of in vitro cell age, culture state at the time of exposure, or the presence of a postirradiation period of arrest

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

    Science.gov (United States)

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

    2014-06-01

    Marine oils rich in ω-3 polyunsaturated fatty acids have been recommended as a preventive treatment for patients at risk for cardiovascular diseases. These oils also are the third most consumed dietary supplement in the USA. However, evidence for their health benefits is equivocal. We tested the daily, isocaloric administration of krill oil (1.17 g oil/kg diet) and Lovaza (Omacor; 4.40 g/kg diet), a pharmaceutical grade fish oil, beginning at 12 months of age, on the life span and mortality-related pathologies of long-lived, male, B6C3F1 mice. The oils were incorporated into the chemically defined American Institute of Nutrition (AIN)-93 M diet. An equivalent volume of soybean oil was removed. Krill oil was 3 % and Lovaza 11 % of the oil in the diets. When their effects were analyzed together, the marine oils significantly shortened life span by 6.6 % (P = 0.0321; log-rank test) relative to controls. Individually, Lovaza and krill oil non-significantly shortened median life span by 9.8 and 4.7 %, respectively. Lovaza increased the number of enlarged seminal vesicles (7.1-fold). Lovaza and krill oil significantly increased lung tumors (4.1- and 8.2-fold) and hemorrhagic diathesis (3.9- and 3.1-fold). Analysis of serum from treated mice found that Lovaza slightly increased blood urea nitrogen, while krill oil modestly increased bilirubin, triglycerides, and blood glucose levels. Taken together, the results do not support the idea that the consumption of isolated ω-3 fatty acid-rich oils will increase the life span or health of initially healthy individuals. PMID:24816553

  1. Life span of mice continuously exposed to low dose rate radiation in long term and their pathological findings

    International Nuclear Information System (INIS)

    Findings in experimental animals exposed to low dose rate radiation are essential for elucidation of its biological effect because its epidemiological human studies performed in such population as the radiation handling personnel involve many unavoidable confounding factors. For the elucidation, authors have conducted an experiment with unusually low dose rate radiation in the specific-pathogen-free (SPF) mouse to see its effect on the life span and pathogenesis, of which outline is given here. All through under the SPF condition, 8 weeks old, male and female SPF mice of B6C3F1 strain were exposed to 137Cs gamma ray at 0, 0.05, 1.1 and 21 mGy/day for 400 days (a half of the average life span of the mouse) in total doses of 0, 20, 400, 800 mGy, respectively, and then maintained until death. Five hundred mice of each sex were included in one rate group, general status and body weight were checked every day, and organ weight measurement and histopathological examination were done at death. Significant shortening of life span was seen in males and females exposed at 21 and at 1.1 and 21 mGy/day, respectively, where 1.1 mGy/day is 400 times as high as the natural radiation dose rate. Major cause of death was malignant lymphoma in both sexes among 10 or more tumors observed. Between exposed and non-exposed groups, the significant increase of tumor incidence was detected in angiosarcoma and myelogenic leukemia of males at 21 mGy/day and ovarian tumor of females at the same rate. It was considered that the life span shortening was not due to the increase of specific tumor incidence by radiation but by early death by many lethal tumors. It was therefore concluded that the long-term continuous low dose rate radiation could induce the early tumorigenesis, tumor growth promotion or both. (K.T.)

  2. Moral development and perceptual role-taking egocentrism: their development and interrelationship across the life-span.

    Science.gov (United States)

    Del Vento Bielby, D; Papalia, D E

    1975-01-01

    Moral judgments and perceptual role taking egocentrism were assessed in seventy-two middle-class people whose age range encompassed a significant portion of the life span. Findings support the anticipated curvilinear relationship between moral development and age, and egocentrism and age. However, the close conceptual development and age, and egocentrism and age. However, the close conceptual relationship between moral development and egocentrism throughout life received only slight statistical support, which attained significance only in the fifteen- to nineteen-year-old age group. The existence of "self-involving" egocentrism was postulated to be an important determinant or moral development during adulthood. PMID:1221055

  3. 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

  4. Circadian rhythms of body temperature and locomotor activity in aging BALB/c mice: early and late life span predictors.

    Science.gov (United States)

    Basso, Andrea; Del Bello, Giovanna; Piacenza, Francesco; Giacconi, Robertina; Costarelli, Laura; Malavolta, Marco

    2016-08-01

    Impairment of one or more parameters of circadian rhythms (CR) of body temperature (BT) and locomotor activity (LMA) are considered among the hallmarks of mammalian aging. These alterations are frequently used as markers for imminent death in laboratory mice. However, there are still contradictory data for particular strains and it is also uncertain which changes might predict senescence changes later in life, including the force of mortality. In the present paper we use telemetry to study LMA and CR of BT during aging of BALB/c mice. At our knowledge this is the first time that CR of BT and LMA are investigated in this strain in a range of age covering the whole lifespan, from young adult up to very old age. CR of BT was analyzed with a cosine model using a cross sectional approach and follow-up measurements. The results show that BT, LMA, amplitude, goodness-of-fit (GoF) to circadian cycle of temperature decrease with different shapes during chronological age. Moreover, we found that the % change of amplitude and BT in early life (5-19 months) can predict the remaining lifespan of the mice. Later in life (22-32 months), best predictors are single measurements of LMA and GoF. The results of this study also offer potential measures to rapidly identifying freely unrestrained mice with the worst longitudinal outcome and against which existing or novel biomarkers and treatments may be assessed. PMID:26820297

  5. Circuit life span in critically ill children on continuous renal replacement treatment: a prospective observational evaluation study

    Science.gov (United States)

    del Castillo, Jimena; López-Herce, Jesús; Cidoncha, Elena; Urbano, Javier; Mencía, Santiago; Santiago, Maria J; Bellón, Jose M

    2008-01-01

    Introduction One of the greatest problems with continuous renal replacement therapy (CRRT) is early coagulation of the filters. Few studies have monitored circuit function prospectively. The purpose of this study was to determine the variables associated with circuit life in critically ill children with CRRT. Methods A prospective observational study was performed in 122 children treated with CRRT in a pediatric intensive care unit from 1996 to 2006. Patient and filter characteristics were analyzed to determine their influence on circuit life. Data were collected on 540 filters in 122 patients and an analysis was performed of the 365 filters (67.6%) that were changed due to circuit coagulation. Results The median circuit life was 31 hours (range 1 to 293 hours). A univariate and multivariate logistic regression study was performed to assess the influence of each one of the factors on circuit life span. No significant differences in filter life were found according to age, weight, diagnoses, pump, site of venous access, blood flow rate, ultrafiltration rate, inotropic drug support, or patient outcome. The mean circuit life span was longer when the heparin dose was greater than 20 U/kg per hour (39 versus 29.1 hours; P = 0.008), with hemodiafiltration compared with hemofiltration (34 versus 22.7 hours; P = 0.001), with filters with surface areas of 0.4 to 0.9 m2 (38.2 versus 26.1 hours; P = 0.01), and with a catheter size of 6.5 French or greater (33.0 versus 25.0 hours; P = 0.04). In the multivariate analysis, hemodiafiltration, heparin dose of greater than 20 U/kg per hour, filter surface area of 0.4 m2 or greater, and initial creatinine of less than 2 mg/dL were associated with a filter life of more than 24 and 48 hours. Total effluent rate of greater than 35 mL/kg per hour was associated only with a filter life of more than 24 hours. Conclusion Circuit life span in CRRT in children is short but may be increased by the use of hemodiafiltration, higher heparin

  6. 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.

  7. Bax-induced apoptosis shortens the life span of DNA repair defect Ku70-knockout mice by inducing emphysema.

    Science.gov (United States)

    Matsuyama, Shigemi; Palmer, James; Bates, Adam; Poventud-Fuentes, Izmarie; Wong, Kelvin; Ngo, Justine; Matsuyama, Mieko

    2016-06-01

    Cells with DNA damage undergo apoptosis or cellular senescence if the damage cannot be repaired. Recent studies highlight that cellular senescence plays a major role in aging. However, age-associated diseases, including emphysema and neurodegenerative disorders, are caused by apoptosis of lung alveolar epithelial cells and neurons, respectively. Therefore, enhanced apoptosis also promotes aging and shortens the life span depending on the cell type. Recently, we reported that ku70(-) (/) (-)bax(-) (/) (-) and ku70(-) (/) (-)bax(+/) (-) mice showed significantly extended life span in comparison with ku70(-) (/) (-)bax(+/+) mice. Ku70 is essential for non-homologous end joining pathway for DNA double strand break repair, and Bax plays an important role in apoptosis. Our study suggests that Bax-induced apoptosis has a significant impact on shortening the life span of ku70(-) (/) (-) mice, which are defective in one of DNA repair pathways. The lung alveolar space gradually enlarges during aging, both in mouse and human, and this age-dependent change results in the decrease of respiration capacity during aging that can lead to emphysema in more severe cases. We found that emphysema occurred in ku70(-) (/) (-) mice at the age of three-months old, and that Bax deficiency was able to suppress it. These results suggest that Bax-mediated apoptosis induces emphysema in ku70(-) (/) (-) mice. We also found that the number of cells, including bronchiolar epithelial cells and type 2 alveolar epithelial cells, shows a higher DNA double strand break damage response in ku70 KO mouse lung than in wild type. Recent studies suggest that non-homologous end joining activity decreases with increased age in mouse and rat model. Together, we hypothesize that the decline of Ku70-dependent DNA repair activity in lung alveolar epithelial cells is one of the causes of age-dependent decline of lung function resulting from excess Bax-mediated apoptosis of lung alveolar epithelial cells (and their

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

    OpenAIRE

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

    2014-01-01

    Marine oils rich in ω-3 polyunsaturated fatty acids have been recommended as a preventive treatment for patients at risk for cardiovascular diseases. These oils also are the third most consumed dietary supplement in the USA. However, evidence for their health benefits is equivocal. We tested the daily, isocaloric administration of krill oil (1.17 g oil/kg diet) and Lovaza (Omacor; 4.40 g/kg diet), a pharmaceutical grade fish oil, beginning at 12 months of age, on the life span and mortality-r...

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

    International Nuclear Information System (INIS)

    A life-span radiation effects study was performed in mice injected with several doses of 226Ra. The study included 788 male C57Bl mice. For the removal of the 226Ra, 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 226Ra lived significantly longer than controls, and, despite appreciable skeletal removal of 226Ra as a result of decorporative treatment, no biological benefit was observed in treated animals. 19 refs., 4 figs., 3 tabs

  10. 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 diso

  11. Nutrition through the life span. Part 3: adults aged 65 years and over.

    Science.gov (United States)

    Shepherd, Alison

    The UK has an ageing population, but this is not being matched by a similar increase in healthy life expectancy. The greatest challenge in the 21st century will be to improve the quality of life as ageing occurs. Health is the most important prerequisite for people to enjoy life in their older years (Brundtland, 1988). Diet is one factor that is believed to play a key role in the prevention and treatment of chronic diseases associated with ageing. The third and final part of this series addressing the concept of nutrition through the lifespan seeks to educate health-care professionals as to what constitutes a healthy diet for the elderly population, and gives practical guidance as to how to try and prevent the ever-growing problem of malnutrition within this age group. It is suggested that when the older adult is hospitalized their risk of malnutrition increases. Therefore, some guidance for the use of oral nutritional supplements in this population is given. Good nutrition and physical exercise are essential for healthy ageing from both a physical and psychological perspective (NICE, 2008). Therefore a multidisciplinary life course approach to ageing is vital to minimizing its complications for quality of life and subsequent public health (Denny, 2008). PMID:19273990

  12. Motives in American Men and Women across the Adult Life Span.

    Science.gov (United States)

    Veroff, Joseph; And Others

    1984-01-01

    Investigates stability and change in four social motives (achievement, affiliation, fear of weakness, hope of power) over the adult life cycle. Motives were assessed in 1957 and 1976 by coding thematic apperceptive content in stories told about six pictures. Some age differences and cohort stability were evident for both sexes. (Author/CB)

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

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Reuben H., E-mail: rkim@dentistry.ucla.edu [UCLA School of Dentistry, Los Angeles, CA 90095 (United States); UCLA Dental Research Institute, Los Angeles, CA 90095 (United States); UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA 90095 (United States); Lieberman, Mark B.; Lee, Rachel [UCLA School of Dentistry, Los Angeles, CA 90095 (United States); Shin, Ki-Hyuk [UCLA School of Dentistry, Los Angeles, CA 90095 (United States); UCLA Dental Research Institute, Los Angeles, CA 90095 (United States); UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA 90095 (United States); Mehrazarin, Shebli; Oh, Ju-Eun [UCLA School of Dentistry, Los Angeles, CA 90095 (United States); Park, No-Hee [UCLA School of Dentistry, Los Angeles, CA 90095 (United States); UCLA Dental Research Institute, Los Angeles, CA 90095 (United States); UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA 90095 (United States); David Geffen School of Medicine at UCLA, Los Angeles, CA 90095 (United States); Kang, Mo K., E-mail: mkang@dentistry.ucla.edu [UCLA School of Dentistry, Los Angeles, CA 90095 (United States); UCLA Dental Research Institute, Los Angeles, CA 90095 (United States); UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA 90095 (United States)

    2010-10-01

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

  14. Bmi-1 extends the life span of normal human oral keratinocytes by inhibiting the TGF-β signaling

    International Nuclear Information System (INIS)

    We previously demonstrated that Bmi-1 extended the in vitro life span of normal human oral keratinocytes (NHOK). We now report that the prolonged life span of NHOK by Bmi-1 is, in part, due to inhibition of the TGF-β signaling pathway. Serial subculture of NHOK resulted in replicative senescence and terminal differentiation and activation of TGF-β signaling pathway. This was accompanied with enhanced intracellular and secreted TGF-β1 levels, phosphorylation of Smad2/3, and increased expression of p15INK4B and p57KIP2. An ectopic expression of Bmi-1 in NHOK (HOK/Bmi-1) decreased the level of intracellular and secreted TGF-β1 induced dephosphorylation of Smad2/3, and diminished the level of p15INK4B and p57KIP2. Moreover, Bmi-1 expression led to the inhibition of TGF-β-responsive promoter activity in a dose-specific manner. Knockdown of Bmi-1 in rapidly proliferating HOK/Bmi-1 and cancer cells increased the level of phosphorylated Smad2/3, p15INK4B, and p57KIP2. In addition, an exposure of senescent NHOK to TGF-β receptor I kinase inhibitor or anti-TGF-β antibody resulted in enhanced replicative potential of cells. Taken together, these data suggest that Bmi-1 suppresses senescence of cells by inhibiting the TGF-β signaling pathway in NHOK.

  15. 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.

  16. Trade-offs between seed output and life span - a quantitative comparison of traits between annual and perennial congeneric species.

    Science.gov (United States)

    Vico, Giulia; Manzoni, Stefano; Nkurunziza, Libère; Murphy, Kevin; Weih, Martin

    2016-01-01

    Perennial plants allocate more resources belowground, thus sustaining important ecosystem services. Hence, shifting from annual to perennial crops has been advocated towards a more sustainable agriculture. Nevertheless, wild perennial species have lower seed production than selected annuals, raising the questions of whether there is a fundamental trade-off between reproductive effort and life span, and whether such trade-off can be overcome through selection. In order to address these questions and to isolate life span from phylogenetic and environmental factors, we conducted a meta-analysis encompassing c. 3000 congeneric annual/perennial pairs from 28 genera. This meta-analysis is complemented with a minimalist model of long-term productivity in perennial species. Perennials allocate more resources belowground and less to seeds than congeneric annuals, independently of selection history. However, existing perennial wheat and rice could achieve yields similar to annuals if they survived three years and each year doubled their biomass, as other perennial grasses do. Selected perennial crops maintain the large belowground allocation of wild perennials, and thus can provide desired regulatory ecosystem services. To match the seed yield of annuals, biomass production of perennial grains must be increased to amounts attained by some perennial grasses - if this goal can be met, perennial crops can provide a more sustainable alternative to annuals. PMID:26214792

  17. Analysis of Genomic Integrity and p53-Dependent G1 Checkpoint in Telomerase-Induced Extended-Life-Span Human Fibroblasts

    OpenAIRE

    Vaziri, Homayoun; Jeremy A Squire; Pandita, Tej K.; Bradley, Grace; Kuba, Robert M.; Zhang, Haihua; Gulyas, Sandor; Hill, Richard P.; Nolan, Garry P.; Benchimol, Samuel

    1999-01-01

    Life span determination in normal human cells may be regulated by nucleoprotein structures called telomeres, the physical ends of eukaryotic chromosomes. Telomeres have been shown to be essential for chromosome stability and function and to shorten with each cell division in normal human cells in culture and with age in vivo. Reversal of telomere shortening by the forced expression of telomerase in normal cells has been shown to elongate telomeres and extend the replicative life span (H. Vazi...

  18. Sex differences in the effects of cocaine abuse across the life span

    OpenAIRE

    Dow-Edwards, Diana

    2010-01-01

    Cocaine alters brain function from the early days of development throughout the entire life of an individual. Since the first preclinical research on cocaine sensitization was published, sex differences in response to the drug in adult rats have been noted. With the appearance of reports on “crack babies” during the 1980’s, sex differences in response to prenatal (developmental) exposure have been identified in both clinical and preclinical reports. Cocaine administered during early developme...

  19. Dead or Alive: Deformed Wing Virus and Varroa destructor Reduce the Life Span of Winter Honeybees

    OpenAIRE

    Dainat, Benjamin; Jay D. Evans; Chen, Yan ping; Gauthier, Laurent; Neumann, Peter

    2012-01-01

    Elevated winter losses of managed honeybee colonies are a major concern, but the underlying mechanisms remain controversial. Among the suspects are the parasitic mite Varroa destructor, the microsporidian Nosema ceranae, and associated viruses. Here we hypothesize that pathogens reduce the life expectancy of winter bees, thereby constituting a proximate mechanism for colony losses. A monitoring of colonies was performed over 6 months in Switzerland from summer 2007 to winter 2007/2008. Indivi...

  20. Early stress evokes dysregulation of histone modifiers in the medial prefrontal cortex across the life span.

    Science.gov (United States)

    Pusalkar, Madhavi; Suri, Deepika; Kelkar, Ashwin; Bhattacharya, Amrita; Galande, Sanjeev; Vaidya, Vidita A

    2016-03-01

    Early stress has been hypothesized to recruit epigenetic mechanisms to mediate persistent molecular, cellular, and behavioral changes. Here, we have examined the consequence of the early life stress of maternal separation (ES) on the gene expression of several histone modifiers that regulate histone acetylation and methylation within the medial prefrontal cortex (mPFC), a key limbic brain region that regulates stress responses and mood-related behavior. ES animals exhibit gene regulation of both writer (histone acetyltransferases and histone methyltransferases) and eraser (histone deacetylases and histone lysine demethylases) classes of histone modifiers. While specific histone modifiers (Kat2a, Smyd3, and Suv420h1) and the sirtuin, Sirt4 were downregulated across life within the mPFC of ES animals, namely at postnatal Day 21, 2 months, and 15 months of age, we also observed gene regulation restricted to these specific time points. Despite the decline noted in expression of several histone modifiers within the mPFC following ES, this was not accompanied by any change in global or residue-specific H3 acetylation and methylation. Our findings indicate that ES results in the regulation of several histone modifiers within the mPFC across life, and suggest that such perturbations may contribute to the altered prefrontal structural and functional plasticity observed following early adversity. © 2015 Wiley Periodicals, Inc. Dev Psychobiol 58: 198-210, 2016. PMID:26395029

  1. 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.

  2. Problem-based learning spanning real and virtual words: a case study in Second Life

    Directory of Open Access Journals (Sweden)

    Judith Good

    2008-12-01

    Full Text Available There is a growing use of immersive virtual environments for educational purposes. However, much of this activity is not yet documented in the public domain, or is descriptive rather than analytical. This paper presents a case study in which university students were tasked with building an interactive learning experience using Second Life as a platform. Both problem-based learning and constructionism acted as framing pedagogies for the task, with students working in teams to design and build a learning experience which could potentially meet the needs of a real client in innovative ways which might not be possible in real life. A process account of the experience is provided, which examines how the pedagogies and contexts (real and virtual influence and enhance each other. The use of a virtual environment, combined with problem-based learning and constructionism, subtly changed the nature of the instructor–student relationship, allowed students to explore ‘problematic problems' in a motivating and relevant manner, provided students with greater ownership over their work, and allowed problems to be set which were flexible, but at the same time allowed for ease of assessment.

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  5. 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.

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

    International Nuclear Information System (INIS)

    On the basis of information gathered from the 239Pu 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

  7. Curiosity and stimulation seeking across the adult life span: cross-sectional and 6- to 8-year longitudinal findings.

    Science.gov (United States)

    Giambra, L M; Camp, C J; Grodsky, A

    1992-03-01

    Giambra (1977-1978, 1979-1980) found that 2 scales of the Imaginal Processes Inventory measuring curiosity (i.e., information seeking) did not change across the adult life span, but 2 measuring stimulation seeking (i.e., boredom) for external stimulation need significantly decreased with age. In this study, these outcomes were replicated (1,356 men and 1,080 women 17 to 92 years old). In addition, a 6- to 8-year longitudinal repeat was obtained on 222 men and 124 women. Significant longitudinal declines were obtained for the stimulation-seeking measures. Furthermore, women showed an increase in impersonal-mechanical curiosity and a decline in interpersonal curiosity, though the amount of change was modest. Men were unchanged on both curiosity measures. Gender differences in longitudinal changes apparently reflected effects of socialization as well as tendencies toward displaying increased androgyny with advancing age. PMID:1558700

  8. Older age may offset genetic influence on affect: The COMT polymorphism and affective well-being across the life span.

    Science.gov (United States)

    Turan, Bulent; Sims, Tamara; Best, Sasha E; Carstensen, Laura L

    2016-05-01

    The catechol-O-methyltransferase (COMT_Val158Met) genetic polymorphism has been linked to variation in affective well-being. Compared with Val carriers, Met carriers experience lower affective well-being. In parallel, research on aging and affective experience finds that younger adults experience poorer affective well-being than older adults. This study examined how COMT and age may interact to shape daily affective experience across the life span. Results suggest that Met (vs. Val) carriers experience lower levels of affective well-being in younger but not in older ages. These findings suggest that age-related improvements in emotional functioning may offset genetic vulnerabilities to negative affective experience. (PsycINFO Database Record PMID:27111524

  9. Effect and Mechanism of Ginsenoside Rg3 on Postoperative Life Span of Patients with Non-Small Cell Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    LU Ping; SU Wei; MIAO Zhan-hui; NIU Hong-rui; LIU Jing; HUA Qin-liang

    2008-01-01

    Objective: To explore the effect and mechanism of ginsenoside Rg3 (Shenyi Capsule,参一胶囊) on the postoperative life span of patients with non-small cell lung cancer (NSCLC). Methods: The prospective, randomized, controlled method was adopted. One hundred and thirty- three patients with NSCLC were randomly assigned to 3 groups: Shenyi Capsule group (43 cases), combined therapy group (Shenyi Capsule plus chemotherapy, 46 cases), and chemotherapy group (44 cases). The survival rates, immune function and the correlation between vascular endothelial growth factor (VEGF) expression and clinical effect were analyzed in the three groups. Results: (1) The 1-year survival rate in the Shenyi group, the combined group and the chemotherapy group was 76.7% (33/43), 82.6% (38/46), and 79.5% (35/44), respectively; the 2-year survival rate was 67.4% (29/43), 71.7% (33/46), and 70.5% (31/44), respectively; and the 3-year survival rate was 46.5% (20/43), 54.3% (25/46), and 47.7% (21/44), respectively. There was no significant difference among the 3 groups (P>0.05). (2) NK cells were increased to different degrees and the ratio of CD4/CD8 was normal in the Shenyi Capsule group and the combined group, while the ratio of CD4/CD8 was disproportional in the chemotherapy group. (3) In the chemotherapy group, the 3-year survival rate was lower in patients with positive expression of VEGF than in patients with negative expression (37.0% vs 64.7%, ~ 2=17.9, P0.05; 44.4% vs 50.0%, P>0.05). Conclusion: Shenyi Capsule, especially in combination with chemotherapy, can improve the life span of patients with NSCLC after operation. The mechanism might be correlated with improving the immune function and anti-tumor angiogenesis.

  10. 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.

  11. Sex differences in the effects of cocaine abuse across the life span.

    Science.gov (United States)

    Dow-Edwards, Diana

    2010-06-01

    Cocaine alters brain function from the early days of development throughout the entire life of an individual. Since the first preclinical research on cocaine sensitization was published, sex differences in response to the drug in adult rats have been noted. With the appearance of reports on "crack babies" during the 1980s, sex differences in response to prenatal (developmental) exposure have been identified in both clinical and preclinical reports. Cocaine administered during early development in the rat produces wide-spread alterations in function which depend on the timing of drug administration as well as the sex of the animal. In males, the response patterns following postnatal days (PND) 11-20 cocaine administration (equivalent to the late prenatal period in humans) are quite similar to those seen following prenatal exposure (equivalent to the first half of pregnancy in humans). There is a general decrease in dopaminergic (DA) markers and reactivity perhaps due to the uncoupling of the D1 receptor from its second messenger system. While similar changes in D1 uncoupling are seen in females, behavioral and metabolic responses to drug challenges generally show increases in DA responsivity (except adolescents) perhaps due to the activational effects of estrogen and/or decreases in serotonin (5-HT) mediated regulation of DA function. We have found that a significant factor in the hyper-responsivity of the female is the role of the testing environment and the responses to stress which can obscure underlying neurochemical dysregulation. Whether parallel factors are operational in adult males and females is currently under investigation. PMID:20045010

  12. 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.

  13. Germ-cell loss extends C. elegans life span through regulation of DAF-16 by kri-1 and lipophilic-hormone signaling.

    Science.gov (United States)

    Berman, Jennifer R; Kenyon, Cynthia

    2006-03-10

    In C. elegans, removing the germ cells extends life span by triggering the nuclear localization and activation of the DAF-16/FOXO transcription factor in the intestine. In this study, we identify and analyze genes required for germline removal to extend life span. We find that the reproductive system communicates with the intestine through lipophilic-hormone signaling and that a gene called kri-1 is likely to act in the intestine to promote DAF-16 nuclear localization in response to this signal. This lipophilic-signaling pathway and kri-1 are not required for DAF-16's nuclear localization and life-span extension in animals with decreased insulin/IGF-1 signaling. Thus, this pathway specifically enables the integration of cues from the reproductive system with central DAF-16-activation pathways to influence the aging of the animal. PMID:16530050

  14. Life span study, 8

    International Nuclear Information System (INIS)

    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)

  15. 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

  16. [The role of clinical suicidology in the system of measures directed towards lowering early mortality and increasing population life span].

    Science.gov (United States)

    Dmitrieva, T B; Polozhiĭ, B S

    2006-01-01

    The level of early mortality has increased substantially in Russia within the last fifteen years, having exceeded the same parameter in developed countries and in the entire post-Soviet area. The second frequent reason for early mortality is a group of factors that includes accidents, suicides, murders, and other external causes. The proportion of suicides in this group is 45 to 50%. As a result, in the recent years the suicide rate in Russia has filled the second place in the world. The authors of this article analyze the suicide rate in different Russian regions, distinguishing between regions with the highest and lowest rate, and characterizing population risk factors of suicidal danger, a special place among which is filled by socioeconomic condition of the regions and the ethnic composition of their population. Increase of the effectiveness of suicide prevention depends on creation of adequate scientific basis, which clinical suicidology can become. The authors substantiate the necessity to distinguish suicidology as a separate field of clinical medicine, and formulate its definition, goals and objectives. Basing on the obtained results, the authors come to a conclusion on the medico-social importance of the development of clinical suicidology in lowering early mortality and increasing the country's population life span. PMID:17002021

  17. Inventions in nanotechnological field provide increased strength and life span of the metal, composite and polymer, metallopolymer structures

    Directory of Open Access Journals (Sweden)

    VLASOV Vladimir Alexeevich

    2014-02-01

    Full Text Available The invention «The method of dispersion of nanoparticles in epoxy resin (RU 2500706» refers to nanotechnological field and it can be applied in different areas of machine industry, transport, construction, power engineering to increase strength and life span of the structures made of metal, composite and polymer, metallopolymer materials, for glue and glue and mechanical joints in different structure elements as well as for compositions which strengthen the stress concentration zones (in the form of holes, cutouts, fillet, thickness differentials in structures, to reform defects, microcracks and other damages occurring in production and performance of structures, to eliminate and encapsulate the gaps in holes and meeting-points of bolted and riveted joints. The invention «The method to produce nanosuspension for manufacturing polymer nanocomposite (RU 2500695» refers to the area of production of polymer nanocomposites based on reactiveplastic binder for space, aircraft, construction and other types of structures (glass-fiber plastic, carbon reinforced plastic, organic plastic, etc.. The method includes preparation of nanosuspension by introducing carbon nanotubes into reactiveplastic binder under ultrasonic treatment with intensity cavity zone 15–25 kW/m². The method makes it possible to optimize the degree of dispersion of carbon nanotubes in binder and to shorten production time of nanocomposites possessing increased strength due to even distribution of nanoparticles in nanocomposite.

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

    Institute of Scientific and Technical Information of China (English)

    LI Jing; PANG Shaojun; LIU Feng; SHAN Tifeng; GAO Suqin

    2013-01-01

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

  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. Physical Attractiveness and Self-Esteem in Middle Childhood: Do Recent Life-Span Developmental Texts Perpetuate or Challenge Gender Stereotypes?

    Science.gov (United States)

    Hensley, Beth H.

    This document reports on an investigation focusing on how the content of introductory college psychology texts' content related to physical attractiveness and self-esteem. The primary objective of this study was to review how recently published life-span developmental texts present physical development in middle childhood as related to traditional…

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

    International Nuclear Information System (INIS)

    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 370C 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

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

    International Nuclear Information System (INIS)

    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.)

  3. Low Six4 and Six5 gene dosage improves dystrophic phenotype and prolongs life span of mdx mice.

    Science.gov (United States)

    Yajima, Hiroshi; Kawakami, Kiyoshi

    2016-08-01

    Muscle regeneration is an important process for skeletal muscle growth and recovery. Repair of muscle damage is exquisitely programmed by cellular mechanisms inherent in myogenic stem cells, also known as muscle satellite cells. We demonstrated previously the involvement of homeobox transcription factors, SIX1, SIX4 and SIX5, in the coordinated proliferation and differentiation of isolated satellite cells in vitro. However, their roles in adult muscle regeneration in vivo remain elusive. To investigate SIX4 and SIX5 functions during muscle regeneration, we introduced knockout alleles of Six4 and Six5 into an animal model of Duchenne Muscular Dystrophy (DMD), mdx (Dmd(mdx) /Y) mice, characterized by frequent degeneration-regeneration cycles in muscles. A lower number of small myofibers, higher number of thick ones and lower serum creatine kinase and lactate dehydrogenase activities were noted in 50-week-old Six4(+/-) 5(+/-) Dmd(mdx) /Y mice than Dmd(mdx) /Y mice, indicating improvement of dystrophic phenotypes of Dmd(mdx) /Y mice. Higher proportions of cells positive for MYOD1 and MYOG (markers of regenerating myonuclei) and SIX1 (a marker of regenerating myoblasts and newly regenerated myofibers) in 12-week-old Six4(+/-) 5(+/-) Dmd(mdx) /Y mice suggested enhanced regeneration, compared with Dmd(mdx) /Y mice. Although grip strength was comparable in Six4(+/-) 5(+/-) Dmd(mdx) /Y and Dmd(mdx) /Y mice, treadmill exercise did not induce muscle weakness in Six4(+/-) 5(+/-) Dmd(mdx) /Y mice, suggesting higher regeneration capacity. In addition, Six4(+/-) 5(+/-) Dmd(mdx) /Y mice showed 33.8% extension of life span. The results indicated that low Six4 and Six5 gene dosage improved dystrophic phenotypes of Dmd(mdx) /Y mice by enhancing muscle regeneration, and suggested that SIX4 and SIX5 are potentially useful de novo targets in therapeutic applications against muscle disorders, including DMD. PMID:27224259

  4. Radiation exposure and the risk of mortality from noncancer respiratory diseases in the life span study, 1950-2005.

    Science.gov (United States)

    Pham, Truong-Minh; Sakata, Ritsu; Grant, Eric J; Shimizu, Yukiko; Furukawa, Kyoji; Takahashi, Ikuno; Sugiyama, Hiromi; Kasagi, Fumiyoshi; Soda, Midori; Suyama, Akihiko; Shore, Roy E; Ozasa, Kotaro

    2013-11-01

    An apparent association between radiation exposure and noncancer respiratory diseases (NCRD) in the Life Span Study (LSS) of atomic bomb survivors has been reported, but the biological validity of that observation is uncertain. This study investigated the possibility of radiation causation of noncancer respiratory diseases in detail by examining subtypes of noncancer respiratory diseases, temporal associations, and the potential for misdiagnosis and other confounding factors. A total of 5,515 NCRD diagnoses listed as the underlying cause of death on the death certificate were observed among the 86,611 LSS subjects with estimated weighted absorbed lung doses. Radiation dose-response analyses were conducted using Cox proportional hazard regression for pneumonia/influenza, other acute respiratory infections, chronic obstructive pulmonary disease and asthma. The linear excess relative risks (ERR) per gray (Gy) were 0.17 (95% CI 0.08, 0.27) for all NCRD and 0.20 (CI 0.09, 0.34) for pneumonia/influenza, which accounted for 63% of noncancer respiratory disease deaths. Adjustments for lifestyle and sociodemographic variations had almost no impact on the risk estimates. However, adjustments for indications of cancer and/or cardiovascular disease decreased the risk estimates, with ERR for total noncancer respiratory diseases declined by 35% from 0.17 to 0.11. Although it was impossible to fully adjust for the misdiagnosis of other diseases as noncancer respiratory diseases deaths in this study because of limitations of available data, nevertheless, the associations were reduced or eliminated by the adjustment that could be made. This helps demonstrates that the association between noncancer respiratory diseases and radiation exposure in previous reports could be in part be attributed to coincident cancer and/or cardiovascular diseases. PMID:24148011

  5. Effect of repetitive acute cold exposures during the last phase of broiler embryogenesis on cold resistance through the life span.

    Science.gov (United States)

    Shinder, D; Rusal, M; Giloh, M; Yahav, S

    2009-03-01

    The time just before hatch is critical, because the embryo shifts toward internal and external pipping. This study aimed to determine the beneficial effect of repeated acute reductions of the incubation temperature during the last phase of broiler embryogenesis on posthatch cold tolerance and on the development of ascites syndrome. Fertile eggs were incubated at 37.8 degrees C and 56% RH. At 18 and 19 d of incubation, 3 treatments were conducted, comprising 2 or 3 exposures to 15 degrees C for 30 or 60 min each. During these cold exposures, egg temperature was measured by infrared thermography to determine sensible heat loss from the eggs. At hatch, BW and body temperature were measured. At 3 and 14 d of age, chicks were challenged by cold exposure to 10 degrees C for 3 h. From 14 d of age onward, three-quarters of the chicks were raised under ascites-inducing conditions (AIC) and the others were raised under regular conditions. The sensible heat loss from the eggs was 512 +/- 66 cal and 718 +/- 126 cal for 30 and 60 min of cold exposure, respectively. No effect of treatment on hatchability was observed, but body temperature and BW were greater to significantly greater in the treated chicks. Cold challenges at 3 and 14 d of age revealed a relative thermoregulatory advantage of embryos exposed to cold for 60 min. Under AIC, fewer treated chickens than controls developed ascites. At 38 d of age, BW and relative breast muscle weight were numerically to significantly greater in the treated chicks than in the control chicks when both were raised under regular conditions, whereas no differences were observed among the chicks raised under AIC. Repeated brief acute cold exposures during the last phase of embryogenesis appeared to improve the ability of growing broilers to withstand low ambient temperatures during their life span. Moreover, chickens treated during embryogenesis improved their performance under regular growth conditions. PMID:19211536

  6. Insights into radionuclide-induced lung cancer in people from life-span studies in beagle dogs

    International Nuclear Information System (INIS)

    In life-span studies, beagle dogs were exposed one time by inhalation to an aerosol containing a beta- or alpha-emitting radionuclide in a relatively soluble or insoluble chemical form. After exposure dogs were observed for late-occurring biological effects. Lung cancer has been a predominant observation for radionuclides inhaled in a relatively insoluble form because most of the absorbed dose was delivered to the lung and contiguous tissues. Approximately 130 lung cancers were observed in dogs exposed to inhaled beta-emitting radionuclides; tumors occurred with absorbed doses to lung ranging from 1100 to 68,000 rads. With inhaled alpha emitters lung tumors occurred at doses between 530 and 8400 rads. Dose rate pattern was shown to be an important factor in the induction of lung cancer by inhaled beta emitters. Doses of low-LET irradiation delivered in a matter of days can be as much as 8 times more effective per unit of dose than radiation doses delivered over a more protracted period of time. Tumors also have occurred in tracheobronchial lymph nodes of dogs that inhaled relatively insoluble forms of beta emitters. From these studies, the risk of lung cancer from inhaled beta- or alpha-emitting radionuclides was compared to determine the importance of LET and other dose-effect modifying factors on resulting risks and on extrapolation to human inhalation exposure. Attention also was given to the risk of cancer in tracheobronchial lymph nodes, on the basis of the results of these studies and the current ICRP computational method in which lymph nodes are included with lung for purposes of dose and risk calculation. 12 refs., 3 figs., 4 tabs

  7. 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

  8. A study on the energy civilization in the 21st century and the analysis of the span of life or the energy recourses

    International Nuclear Information System (INIS)

    This study should have been mainly composed of the pre-estimate of the future views on the balancing of energy demand and supply in the 21st century related to global environmental matters and the analysis of the span of life of the usable energy resources in the 21st century. Due to the project interruption by the PBS input, this study carried out partly the investigation and the analysis of energy demand supply, which regarded to economic circumstances and environmental control regulations. Therefore, this intermediate report shall be an important reference to analyze the span of practical life of the usable energy resources in order to improve the usable capability of energy utilization for the future. 14 refs. (Author)

  9. 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.

    been reported to occur suddenly after a series of parthenogenetic gener- ations (Zhong et al. 1989). In the present study also, three sexual males were encountered during the later part of the study while being mass reared. Studies have been initiated... the life span of females. However, long-term feeding experiments revealed that the percentage survival was high with I. galbana and low with C. cal- citrans. Introduction Diaphanosoma celebensis (Crustacea:Cladocera:Sididae) is a low to medium saline...

  10. Sexual Dimorphism in the Effect of a Taurine Supplemented Diet on Life Span in Adult Drosophila melanogaster

    OpenAIRE

    Milne, A; B. Talon; S. Shirkey; Habib, I.; Smith, L.A.; J. Nadolski

    2011-01-01

    As the amino acid taurine is being used more frequently in human and animal diets, the exact physiological role and benefit have not been fully elucidated. To determine if taurine can impact long term physiology, we investigated the effects of a chronic taurine supplemented diet using the model organism, Drosophila melanogaster. We specifically studied how life span and development are affected. A pairwise comparison of survival curves found a significant difference between male and female fr...

  11. 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....

  12. Acacetin 7-O-α-l-rhamnopyranosyl (1-2) β-D-xylopyranoside Elicits Life-span Extension and Stress Resistance in Caenorhabditis elegans.

    Science.gov (United States)

    Asthana, Jyotsna; Yadav, Deepti; Pant, Aakanksha; Yadav, A K; Gupta, M M; Pandey, Rakesh

    2016-09-01

    The advancements in the field of gerontology have unraveled the signaling pathways that regulate life span, suggesting that it might be feasible to modulate aging. To this end, we isolated a novel phytomolecule Acacetin 7-O-α-l-rhamnopyranosyl (1-2) β-D-xylopyranoside (ARX) from Premna integrifolia and evaluated its antiaging effects in Caenorhabditis elegans The spectral data analysis revealed the occurrence of a new compound ARX. Out of the three tested pharmacological doses of ARX, viz. 5, 25, and 50 µM, the 25-µM dose was able to extend life span in C. elegans by more than 39%. The present study suggests that ARX affects bacterial metabolism, which in turn leads to dietary restriction (DR)-like effects in the worms. The effect of ARX on worms with mutations (mev-1, eat-2, sir-2.1, skn-1, daf-16, and hsf-1) indicates that ARX-mediated life-span extension involves mechanisms associated with DR and maintenance of cellular redox homeostasis. This study is the first time report on longevity-promoting activity of ARX in C. elegans mediated by stress and DR-regulating genes. This novel phytomolecule can contribute in designing therapeutics for managing aging and age-related diseases. PMID:26433219

  13. Effects of radiation and lifestyle factors on risks of urothelial carcinoma in the Life Span Study of atomic bomb survivors.

    Science.gov (United States)

    Grant, E J; Ozasa, K; Preston, D L; Suyama, A; Shimizu, Y; Sakata, R; Sugiyama, H; Pham, T-M; Cologne, J; Yamada, M; De Roos, A J; Kopecky, K J; Porter, M P; Seixas, N; Davis, S

    2012-07-01

    Among the Life Span Study (LSS) of Atomic-bomb survivors, recent estimates showed that unspecified bladder cancer had high radiation sensitivity with a notably high female-to-male excess relative risk (ERR) per radiation dose ratio and were the only sites for which the ERR did not decrease with attained age. These findings, however, did not consider lifestyle factors, which could potentially confound or modify the risk estimates. This study estimated the radiation risks of the most prevalent subtype of urinary tract cancer, urothelial carcinoma, while accounting for smoking, consumption of fruit, vegetables, alcohol and level of education (a surrogate for socioeconomic status). Eligible study subjects included 105,402 (males = 42,890) LSS members who were cancer-free in 1958 and had estimated radiation doses. Members were censored due to loss of follow-up, incident cancer of another type, death, or the end of calendar year 2001. Surveys (by mail or clinical interview) gathered lifestyle data periodically for 1963-1991. There were 63,827 participants in one or more survey. Five hundred seventy-three incident urothelial carcinoma cases occurred, of which 364 occurred after lifestyle information was available. Analyses were performed using Poisson regression methods. The excess relative risk per weighted gray unit (the gamma component plus 10 times the neutron component, Gy(w)) was 1.00 (95% CI: 0.43-1.78) but the risks were not dependent upon age at exposure or attained age. Lifestyle factors other than smoking were not associated with urothelial carcinoma risk. Neither the magnitude of the radiation ERR estimate (1.00 compared to 0.96), nor the female-to-male (F:M) ERR/Gy(w) ratio (3.2 compared to 3.4) were greatly changed after accounting for all lifestyle factors. A multiplicative model of gender-specific radiation and smoking effects was the most revealing though there was no evidence of significant departures from either the additive or multiplicative joint

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

    OpenAIRE

    Zheheng Chen; Tong Guo; Shengyou Yan

    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...

  15. From Suns to Life: A Chronological Approach to the History of Life on Earth 7. Ancient Fossil Record and Early Evolution (ca. 3.8 to 0.5 Ga)

    Science.gov (United States)

    López-Garcia, Purificacón; Moreira, David; Douzery, Emmanuel; Forterre, Patrick; van Zuilen, Mark; Claeys, Philippe; Prieur, Daniel

    2006-06-01

    Once life appeared, it evolved and diversified. From primitive living entities, an evolutionary path of unknown duration, likely paralleled by the extinction of unsuccessful attempts, led to a last common ancestor that was endowed with the basic properties of all cells. From it, cellular organisms derived in a relative order, chronology and manner that are not yet completely settled. Early life evolution was accompanied by metabolic diversification, i.e. by the development of carbon and energy metabolic pathways that differed from the first, not yet clearly identified, metabolic strategies used. When did the different evolutionary transitions take place? The answer is difficult, since hot controversies have been raised in recent years concerning the reliability of the oldest life traces, regardless of their morphological, isotopic or organic nature, and there are also many competing hypotheses for the evolution of the eukaryotic cell. As a result, there is a need to delimit hypotheses from solid facts and to apply a critical analysis of contrasting data. Hopefully, methodological improvement and the increase of data, including fossil signatures and genomic information, will help reconstructing a better picture of life evolution in early times as well as to, perhaps, date some of the major evolutionary transitions. There are already some certitudes. Modern eukaryotes evolved after bacteria, since their mitochondria derived from ancient bacterial endosymbionts. Once prokaryotes and unicellular eukaryotes had colonized terrestrial ecosystems for millions of years, the first pluricellular animals appeared and radiated, thus inaugurating the Cambrian. The following sections constitute a collection of independent articles providing a general overview of these aspects.

  16. Antioxidant Capacity of “Mexican Arnica” Heterotheca inuloides Cass Natural Products and Some Derivatives: Their Anti-Inflammatory Evaluation and Effect on C. elegans Life Span

    Directory of Open Access Journals (Sweden)

    José Luis Rodríguez-Chávez

    2015-01-01

    Full Text Available It has been suggested that the accumulation of biomolecular damage caused by reactive oxygen species (ROS contributes to aging. The antioxidant activity is related to the ability of certain compounds to protect against the potentially harmful effect of processes or reactions involving ROS. This ability is associated with the termination of free radical propagation in biological systems. From Heterotheca inuloides various compounds which have shown to possess antioxidant capacity and scavenging ROS. The aim of this study was to determine the antioxidant capacity of additional natural components isolated from H. inuloides and some semisynthetic derivatives, their anti-inflammatory activity and the effect on Caenorhabditis elegans nematode life span. Compounds showed ability to inhibit various biological processes such as lipid peroxidation, scavenge nonbiological important oxidants such as 1O2, OH∙, H2O2, and HOCl and scavenge non biological stable free radicals (DPPH. Some cadinane type compounds showed possess antioxidant, ROS scavenging capacity, anti-inflammatory activity, and effect on the C. elegans life span. Flavonoid type compounds increased the life of the nematode and quercetin was identified as the compound with the greatest activity. The modification of chemical structure led to a change in the antioxidant capacity, the anti-inflammatory activity, and the survival of the worm.

  17. Application of a systematized nomenclature of veterinary medicine (SNOVET) to diagnostic coding and retrieval of clinical life-span data in beagle dogs exposed to plutonium

    International Nuclear Information System (INIS)

    A data-management system, utilizing the Systematized Nomenclature of Veterinary Medicine (SNOVET), was implemented to collect data generated by our life-span canine studies. Information is encoded and retrieved by specific categories. These data are analyzed statistically to look for significant effects related to exposure to radionuclides. Preliminary use for evaluation of the SNOVET system revealed statistically significant differences in survival between control and exposed animals. Also, there appears to be an increased risk of testicular and reproductive tract disorders with increasing dose. 8 refs., 3 figs., 2 tabs

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

    International Nuclear Information System (INIS)

    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 239Pu or 226Ra is reviewed; life shortening at low dose levels of 226Ra is presented. 21 refs., 1 tab

  19. Dead or alive: Deformed Wing Virus and Varroa destructor reduce the life span of winter honey bees

    Science.gov (United States)

    Elevated winter losses of managed honey bee colonies are a major concern, but the underlying mechanisms remain controversial. Among suspects are the parasitic mite Varroa destructor, the microsporidian Nosema ceranae and associated viruses. Here, we hypothesize that pathogens reduce the life expecta...

  20. Comparison of chronological and corrected ages in the gross motor assessment of low-risk preterm infants during the first year of life Comparação das idades cronológica e corrigida na avaliação motora grosseira de lactentes pré-termo com baixo risco no primeiro ano de vida

    OpenAIRE

    Ana Paula Restiffe; José Luiz Dias Gherpelli

    2006-01-01

    OBJECTIVE: To evaluate the need of chronological age correction according to the degree of prematurity, when assessing gross motor development in preterm infants, during the first year of life. METHOD: Cohort, observational and prospective study. Alberta Infant Motor Scale (AIMS) was used to evaluate 43 preterm infants with low risk for motor neurological sequelae, during the first year of corrected age. Mean scores were analyzed according to chronological and corrected ages. Children with mo...

  1. Extracts of Cistanche deserticola Can Antagonize Immunosenescence and Extend Life Span in Senescence-Accelerated Mouse Prone 8 (SAM-P8 Mice

    Directory of Open Access Journals (Sweden)

    Ke Zhang

    2014-01-01

    Full Text Available The senescence accelerated mouse prone 8 substrain (SAM-P8, widely accepted as an animal model for studying aging and antiaging drugs, was used to examine the effects of dietary supplementation with extracts of Cistanche deserticola (ECD which has been used extensively in traditional Chinese medicine because of its perceived ability to promote immune function in the elderly. Eight-month-old male SAM-P8 mice were treated with ECD by daily oral administrations for 4 weeks. The results showed that dietary supplementation of 150 mg/kg and 450 mg/kg of ECD could extend the life span measured by Kaplan-Meier survival analysis in dose-dependent manner. Dietary supplementation of SAM-P8 mice for 4 weeks with 100, 500, and 2500 mg/kg of ECD was shown to result in significant increases in both naive T and natural killer cells in blood and spleen cell populations. In contrast, peripheral memory T cells and proinflammatory cytokine, IL-6 in serum, were substantially decreased in the mice that ingested 100 and 500 mg/kg of ECD daily. Additionally, Sca-1 positive cells, the recognized progenitors of peripheral naive T cells, were restored in parallel. Our results provide clear experimental support for long standing clinical observational studies showing that Cistanche deserticola possesses significant effects in extending life span and suggest this is achieved by antagonizing immunosenescence.

  2. 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

    2016-01-01

    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.

  3. 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.

  4. 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)

    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. Cu2+ and Mn2+ 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)

  5. Phototoxic effect of UVR on wild type, ebony and yellow mutants of Drosophila melanogaster: Life Span, fertility, courtship and biochemical aspects

    Institute of Scientific and Technical Information of China (English)

    WANG ZhePeng; LIU RuiFang; WANG AnRu; DU LiLi; DENG XueMei

    2008-01-01

    Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of photo-toxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid per-oxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In con-clusion, our results suggested that UVB can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals, w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding against UV and scavenging free radicals produced by UVR should be responsible for their different sensitivity to UVR.

  6. Estimation of life-span of instrumentation and control cables used in nuclear power plants using the tensile testing methodology

    International Nuclear Information System (INIS)

    Nuclear Power Plants (NPPs) contain myriads of electrical cables of all sizes, voltage ratings and lengths delivering electrical power to much vital, as well as non-vital equipment. These cables are insulated with some form of polymeric insulation. These insulating materials will gradually age from exposure to heat, radiation, moisture and chemicals. Hence, on-site testing of the conditions of these cables is necessary to ensure their continued reliability in service and to predict their remaining life. In addition these cables must operate reliably in the harsh steam environments produced by postulated design-basis events (e.g. LOCA). Conservatively, this event is assumed to occur at the end of the planned service life of the NPPs. Evidence must be provided prior to their installation that the affected cables can meet the specified functional requirements. Usually this evidence is provided by the results of the qualification tests, simulating operational aging, the LOCA and the post accident phase. Research efforts are continuing, through out the world, for developing effective testing methods which can assess the present condition of a cable's electrical property and can also predict the remaining life and LOCA survivability with some assurance. It has been found that the insulation resistance of cables are not much affected by ageing. Experience has shown that the failure of nuclear cables is primarily due to the hardening and embrittlement of the insulation resulting in the formation of micro cracks, a loss of dielectric strength and high leakage currents. The elongation at break measurements carried on various cables subjected to accelerated thermal ageing were used to arrive at Arrhenius parameters based on an acceptable 65% elongation at break criteria. Life estimation have been carried at operating temperatures using these parameters. (author)

  7. Circuit life span in critically ill children on continuous renal replacement treatment: a prospective observational evaluation study

    OpenAIRE

    del Castillo, Jimena; López-Herce, Jesús; Cidoncha, Elena; Urbano, Javier; Mencía, Santiago; Santiago, Maria J; Bellón, Jose M

    2008-01-01

    Introduction One of the greatest problems with continuous renal replacement therapy (CRRT) is early coagulation of the filters. Few studies have monitored circuit function prospectively. The purpose of this study was to determine the variables associated with circuit life in critically ill children with CRRT. Methods A prospective observational study was performed in 122 children treated with CRRT in a pediatric intensive care unit from 1996 to 2006. Patient and filter characteristics were an...

  8. Life-span shortening and disease incidence in male BALB/c and C57BL mice after single, fractionated d(50)-Be neutron or gamma exposure

    International Nuclear Information System (INIS)

    Life-span shortening and causes of death, ascertained by autopsy and histological examination at the time of spontaneous death, after single or fractionated x-ray, gamma, or d(50)-Be neutron irradiation, are being studied for two mouse strains (BALB/c and C57BL) with different disease characteristics. Fractionation schedules that have been implemented are x rays, four weekly exposures (C57BL); gamma rays, 10 daily exposures (BALB/c; and neutrons, eight exposures at 3-h intervals (C57BL). The data are incomplete but suggest that the dependency of life shortening on dose is related to the types of effects induced by radiation and results in different functions, linear or sigmoid, for the two mouse strains. Fractionated gamma irradiation causes more tumors than single exposure, but, generally, this is a result of multiple tumors occurring in animals. The relative biological effectiveness (RBE) for life shortening for d(50)-Be neutrons as compared to gamma rays is on the order of 1 to 2 and is slightly greater for the C57BL than for the BALB/c strain. 18 refs., 2 figs., 3 tabs

  9. Differential effects of IGF-1 deficiency during the life span on structural and biomechanical properties in the tibia of aged mice.

    Science.gov (United States)

    Ashpole, Nicole M; Herron, Jacquelyn C; Estep, Patrick N; Logan, Sreemathi; Hodges, Erik L; Yabluchanskiy, Andriy; Humphrey, Mary Beth; Sonntag, William E

    2016-04-01

    Advanced aging is associated with the loss of structural and biomechanical properties in bones, which increases the risk for bone fracture. Aging is also associated with reductions in circulating levels of the anabolic signaling hormone, insulin-like growth factor (IGF)-1. While the role of IGF-1 in bone development has been well characterized, the impact of the age-related loss of IGF-1 on bone aging remains controversial. Here, we describe the effects of reducing IGF-1 at multiple time points in the mouse life span--early in postnatal development, early adulthood, or late adulthood on tibia bone aging in both male and female igf (f/f) mice. Bone structure was analyzed at 27 months of age using microCT. We find that age-related reductions in cortical bone fraction, cortical thickness, and tissue mineral density were more pronounced when IGF-1 was reduced early in life and not in late adulthood. Three-point bone bending assays revealed that IGF-1 deficiency early in life resulted in reduced maximum force, maximum bending moment, and bone stiffness in aged males and females. The effects of IGF-1 on bone aging are microenvironment specific, as early-life loss of IGF-1 resulted in decreased cortical bone structure and strength along the diaphysis while significantly increasing trabecular bone fraction and trabecular number at the proximal metaphysis. The increases in trabecular bone were limited to males, as early-life loss of IGF-1 did not alter bone fraction or number in females. Together, our data suggest that the age-related loss of IGF-1 influences tibia bone aging in a sex-specific, microenvironment-specific, and time-dependent manner. PMID:26968399

  10. Future Chronological Boundary

    CERN Document Server

    Harris, S G

    1997-01-01

    The purpose of this note is to establish, in a categorical manner, the universality of the Geroch-Kronheimer-Penrose causal boundary when considering the types of causal structures that may profitably be put on any sort of boundary for a spacetime. Actually, this can only be done for the future causal boundary (or the past causal boundary) separately; furthermore, only the chronology relation, not the causality relation, is considered, and the GKP topology is eschewed. The final result is that there is a unique map, with the proper causal properties, from the future causal boundary of a spacetime onto any ``reasonable" boundary which supports some sort of chronological structure and which purports to consist of a future completion of the spacetime. Furthermore, the future causal boundary construction is categorically unique in this regard.

  11. Late effects of selected immunosuppressants on immunocompetence, disease incidence, and mean life-span. II. Cell-mediated immune activity. [Mice, X radiation

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, W.J.; Perkins, E.H.; Goodman, S.A.; Hori, Y.; Halsall, M.K.; Makinodan, T.

    1975-01-01

    The late effects of various immunosuppressive insults on cell-mediated immunity in mice were studied in an attempt to assess the role of immune surveillance in the aging process. Results were obtained using susceptibility to allogeneic tumor cell challenge, graft-versus-host reaction (GVHR), blastogenic response to PHA, a thymus derived T cell-specific plant mitogen, and cytolytic activity against allogeneic tumor cells as measures of immunologic activity. In vivo studies late in life show that resistance to allogeneic tumor cells is significantly decreased in thymectomized mice, whereas those treated with cortisone, cyclophosphamide and sublethal x-ray remain unchanged. Spleen cells from only the thymectomized and the sublethally irradiated mice show reduced activity in the GVHR. No difference is seen in the activity of bone marrow cells. Results consistent with these findings were obtained in in vitro studies. Thus spleen cells from thymectomized or sublethally irradiated mice show decreased activity in response to PHA, whereas no change is seen in spleen cells from other treated groups. Hence, surgical and physical insults are more likely to induce long-lasting immunosuppression in those immunocompetent tissues whose activity normally diminishes with advancing age. Furthermore, the degree of immunosuppression seen in this study is not of the order of magnitude that one could reasonably predict a significant decrease in mean life-span.

  12. Deletion of the cardiolipin-specific phospholipase Cld1 rescues growth and life span defects in the tafazzin mutant: implications for Barth syndrome.

    Science.gov (United States)

    Ye, Cunqi; Lou, Wenjia; Li, Yiran; Chatzispyrou, Iliana A; Hüttemann, Maik; Lee, Icksoo; Houtkooper, Riekelt H; Vaz, Frédéric M; Chen, Shuliang; Greenberg, Miriam L

    2014-02-01

    Cardiolipin (CL) that is synthesized de novo is deacylated to monolysocardiolipin (MLCL), which is reacylated by tafazzin. Remodeled CL contains mostly unsaturated fatty acids. In eukaryotes, loss of tafazzin leads to growth and respiration defects, and in humans, this results in the life-threatening disorder Barth syndrome. Tafazzin deficiency causes a decrease in the CL/MLCL ratio and decreased unsaturated CL species. Which of these biochemical outcomes contributes to the physiological defects is not known. Yeast cells have a single CL-specific phospholipase, Cld1, that can be exploited to distinguish between these outcomes. The cld1Δ mutant has decreased unsaturated CL, but the CL/MLCL ratio is similar to that of wild type cells. We show that cld1Δ rescues growth, life span, and respiratory defects of the taz1Δ mutant. This suggests that defective growth and respiration in tafazzin-deficient cells are caused by the decreased CL/MLCL ratio and not by a deficiency in unsaturated CL. CLD1 expression is increased during respiratory growth and regulated by the heme activator protein transcriptional activation complex. Overexpression of CLD1 leads to decreased mitochondrial respiration and growth and instability of mitochondrial DNA. However, ATP concentrations are maintained by increasing glycolysis. We conclude that transcriptional regulation of Cld1-mediated deacylation of CL influences energy metabolism by modulating the relative contribution of glycolysis and respiration. PMID:24318983

  13. Censorship of Chronological Violations

    CERN Document Server

    Monroe, H

    2006-01-01

    Rich non-arbitrary topological change may occur in a relativistic vacuum space-time that violates chronology at every point. However, each closed timelike curve (CTC) is typically "censored" by passing through a wormhole's event horizon, and a Cauchy-like surface may exist through which all timelike curves pass once and only once before crossing an event horizon. All CTCs in a time-orientable space-time must pass through a wormhole; otherwise the CTC could be deformed as a CTC to a non-time-orientable point. Therefore, if all wormholes have event horizons, there is chronology protection against uncensored CTCs, and the universe is safe for those historians who cannot see through event horizons. An indicator of a space-time's completeness which is conformally invariant, unlike geodesic or b-completeness, is that no causal boundary exists, which implies that the entire space-time is a chronology violating set. Such "causally complete" space-times fail to satisfy assumptions of the topological censorship theorem...

  14. Cardiovascular determinants of life span

    OpenAIRE

    Shi, Y; Camici, G G; Lüscher, T. F.

    2010-01-01

    The prevalence of cardiovascular diseases rises with aging and is one of the main causes of mortality in western countries. In view of the progressively aging population, there is an urge for a better understanding of age-associated cardiovascular diseases and its underlying molecular mechanisms. The risk factors for cardiovascular diseases include unhealthy diet, diabetes, obesity, smoking, alcohol consumption, physical inactivity, and aging. Increased production of oxygen-derived free radic...

  15. Intelligence across the life span

    OpenAIRE

    Whitaker, Simon

    2015-01-01

    Purpose The aim of this paper is to present a theoretical explanation as to why young people score higher on IQ tests than their parents would have done at the same age. Background It is now well established that IQ tests score higher as they get older by about .3 of an IQ point per year for each year since they were standardized. So if the average 20 year old in 1972 was given an IQ test standardized in 2015 they would get a measured IQ of about 87, whereas the average 20 year o...

  16. 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.

  17. Phototoxic effect of UVR on wild type, ebony and yellow mutants of Drosophila melanogaster: Life Span, fertility, courtship and biochemical aspects

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of photo- toxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid per- oxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P<0.0001) than those of y in the UV-exposed groups, but not for the control. On the other hand, UV exposure had an adverse effect on courtship of flies. Stronger electron paramagnetic resonance (EPR) signals could be detected in w, e and y exposed to 5 min UV. And there were more significant changes of EPR signals in y than in w and e. UVR had no significant (P=0.1782) effect on the SOD activities. After pooling data from the control and UV-exposed groups, we found that w had a significantly (P<0.05) higher level of SOD activity, but e and y were nearly at the same levels (P>0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In con- clusion, our results suggested that UVR can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals. w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding

  18. Real Wage Chronology

    OpenAIRE

    Amy Peng; Louis N. Christofides

    2009-01-01

    We process information in a large number of Canadian wage contracts, signed over a period of several decades, to generate the long-run history of the real wage for each bargaining pair. We term these hitherto unexamined histories ‘chronologies’. We are able to generate 1574 continuous real wage chronologies and we examine the evolution of the real wage in each case. We explore the influence of productivity growth, the labour relations record of the pair, the influence of industry and region a...

  19. Biomarkers of aging, life span and spontaneous carcinogenesis in the wild type and HER-2 transgenic FVB/N female mice.

    Science.gov (United States)

    Panchenko, Andrey V; Popovich, Irina G; Trashkov, Alexandr P; Egormin, Peter A; Yurova, Maria N; Tyndyk, Margarita L; Gubareva, Ekaterina A; Artyukin, Ilia N; Vasiliev, Andrey G; Khaitsev, Nikolai V; Zabezhinski, Mark A; Anisimov, Vladimir N

    2016-04-01

    FVB/N wild type and transgenic HER-2/neu FVB/N female mice breed at N.N. Petrov Research Institute of Oncology were under observation until natural death without any special treatment. Age-related dynamics of body weight, food consumption and parameters of carbohydrate and lipid metabolism, level of nitric oxide, malonic dialdehyde, catalase, Cu, Zn-superoxide dismutase, vascular endothelial growth factor were studied in both mice strains. The parameters of life span and tumor pathology were studied as well. Cancer-prone transgenic HER-2/neu mice developed in 100 % multiple mammary adenocarcinomas and died before the age of 1 year. Forty tree percent of long-lived wild type mice survived the age of 2 years and 19 %-800 days. The total tumor incidence in wild type mice was 34 %. The age-associated changes in the level of serum IGF-1, glucose and insulin started much earlier in transgene HER-2/neu mice as compared with wild type FVB/N mice. It was suggested that transgenic HER-2/neu involves in initiation of malignization of mammary epithelial cells but also in acceleration of age-related hormonal and metabolic changes in turn promoting mammary carcinogenesis. PMID:26423570

  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. 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.

  2. Nuclear cosmo-chronology

    International Nuclear Information System (INIS)

    Nuclear cosmo-chronology is based on the age determination method by using pairs of isotopes or elements: 235U / 238U, 187Re / 187Os 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.)

  3. Span of Control and Span of Activity

    OpenAIRE

    Oriana Bandiera; Andrea Prat; Raffaella Sadun; Julie Wulf

    2012-01-01

    For both practitioners and researchers, span of control plays an important role in defining and understanding the role of the CEO. In this paper, we combine organizational chart information for a sample of 65 companies with detailed data on how their CEOs allocate their work time, which we define as their span of activity. Span of activity provides a direct measure of the CEO's management style, including the attention devoted to specific subordinates and functions, the time devoted to indivi...

  4. Models for Chronology Selection

    CERN Document Server

    Cassidy, M J

    1998-01-01

    In this paper, we derive an expression for the grand canonical partition function for a fluid of hot, rotating massless scalar field particles in the Einstein universe. We consider the number of states with a given energy as one increases the angular momentum so that the fluid rotates with an increasing angular velocity. We find that at the critical value when the velocity of the particles furthest from the origin reaches the speed of light, the number of states tends to zero. We illustrate how one can also interpret this partition function as the effective action for a boosted scalar field configuration in the product of three dimensional de Sitter space and $S^1$. In this case, we consider the number of states with a fixed linear momentum around the $S^1$ as the particles are given more and more boost momentum. At the critical point when the spacetime is about to develop closed timelike curves, the number of states again tends to zero. Thus it seems that quantum mechanics naturally enforces the chronology p...

  5. Models for chronology selection

    Science.gov (United States)

    Cassidy, M. J.; Hawking, S. W.

    1998-02-01

    In this paper, we derive an expression for the grand canonical partition function for a fluid of hot, rotating massless scalar field particles in the Einstein universe. We consider the number of states with a given energy as one increases the angular momentum so that the fluid rotates with an increasing angular velocity. We find that at the critical value when the velocity of the particles furthest from the origin reaches the speed of light, the number of states tends to zero. We illustrate how one can also interpret this partition function as the effective action for a boosted scalar field configuration in the product of three dimensional de Sitter space and S1. In this case, we consider the number of states with a fixed linear momentum around the S1 as the particles are given more and more boost momentum. At the critical point when the spacetime is about to develop closed timelike curves, the number of states again tends to zero. Thus it seems that quantum mechanics naturally enforces the chronology protection conjecture by superselecting the causality violating field configurations from the quantum mechanical phase space.

  6. Nuclear cosmo-chronology

    International Nuclear Information System (INIS)

    The nuclear cosmo-chronology is based on radioactive dating which makes use of isotope or element pairs. In this paper we investigate the galaxy age estimations which can be deduced from meteorite analysis and solar or certain old stars light absorption spectra. These evaluations are based on theoretical models different then those implied in cosmology. They imply the calculation of heavy nuclei production in r process. The most significant difficulty of this calculation arises from the necessity of simultaneous evaluation of the production of a large number of nuclei what implies the difficult application of the microscopic nuclear models. Since the solar system is young as compared to the age of galaxy the evaluation based on element abundances (deduced from sun absorption spectra or meteorite analyses) requires a chemical evolution model of the galaxy. So far such an evaluation based on all the pairs of nuclear chronometers was not possible with a single set of parameters. Recent progress in estimating the absorption neutron cross section and decay schemes in the star inner environment will allow solving this difficulty

  7. Built environment, health and how old you are: A view across the life span - 20th Annual John K. Friesen Conference - Growing Old in a Changing Climate: Exploring the Interface Between Population Aging and Global Warming (2011)

    OpenAIRE

    Frank, Larry

    2011-01-01

    This video clip comprises the four presentations of Panel Session 4, “Preparing Aging Populations for Climate Change in British Columbia and Beyond” held at the 20th Annual John K. Friesen Conference, "Growing Old in a Changing Climate: Exploring the Interface Between Population Aging and Global Warming," MAY 25-26, 2011, Vancouver, BC. Dr. Larry Frank "Built environment, health and how old you are: A view across the life span" - Talk focuses upon the relationships between the designs of the ...

  8. 闵尔昌《江子屏先生年谱》校点二种正误%Correction to the Emendations and Punctuations of a Chronological Life of Mr. Jiang Ting by Min Erchang

    Institute of Scientific and Technical Information of China (English)

    高明峰

    2012-01-01

    A Chronological Life of Mr. Jiang Ziping by 1VAn Erchang is important in the study of Jiang Fan and even the academy in Qing dynasty, which has been collated by Qi Yongxiang, and also by Zheng Xiaoxia and Wu Ping. Qi's revision has 29 errors, including 14 word-missings, 6 abundant words, 8 word faults, 1 inverted mistake, as well as 8 punctuation errors, including 5 period and comma mistakes and 3 wrong marks. The version by Zheng X aoxia and Wu Ping have the following two problems: the wrong note format and punctuation errors.%闵尔昌《江子屏先生年谱》是研究江藩乃至清代学术的重要资料。漆永祥和郑晓霞、吴平分别对其进行了校点整理。漆永祥校点本存在文字错误共有29处,含脱误14处,衍误6处,讹误8处,倒误1处。另有标点错误8处,含句逗不当5处,专名线标示不当3处。郑晓霞、吴平标点本存在闵尔昌《江子屏先生年谱》注文标识不当以及标点失误两大问题。

  9. Chronological objects in demographic research

    Directory of Open Access Journals (Sweden)

    Frans J. Willekens

    2013-03-01

    Full Text Available BACKGROUND Calendar time, age and duration are chronological objects. They represent an instant or a time period. Age and duration are usually expressed in units with varying lengths. The number of days in a month or a year depends on the position on the calendar. The units are also not homogeneous and the structure influences measurement. One solution, common in demography, is to use units that are large enough for the results not to be seriously affected by differences in length and structure. Another approach is to take the idiosyncrasy of calendars into account and to work directly with calendar dates. The technology that enables logical and arithmetic operations on dates is available. OBJECTIVE To illustrate logical and arithmetic operations on dates and conversions between time measurements. METHODS Software packages include utilities to process dates. I use existing and a few new utilities in R to illustrate operations on dates and conversions between calendar dates and elapsed time since a reference moment or a reference event. Three demographic applications are presented. The first is the impact of preferences for dates and days on demographic indicators. The second is event history analysis with time-varying covariates. The third is microsimulation of life histories in continuous time. CONCLUSIONS The technology exists to perform operations directly on dates, enabling more precise calculations of duration and elapsed time in demographic analysis. It eliminates the need for (a approximations and (b transformations of dates, such as Century Month Code, that are convenient for computing durations but are a barrier to interpretation. Operations on dates, such as the computation of age, should consider time units of varying length.

  10. Uniform random spanning trees

    OpenAIRE

    Pemantle, Robin

    2004-01-01

    There are several good reasons you might want to read about uniform spanning trees, one being that spanning trees are useful combinatorial objects. Not only are they fundamental in algebraic graph theory and combinatorial geometry, but they predate both of these subjects, having been used by Kirchoff in the study of resistor networks. This article addresses the question about spanning trees most natural to anyone in probability theory, namely what does a typical spanning tree look like?

  11. Chronological objects in demographic research

    NARCIS (Netherlands)

    Willekens, F.J.C.

    2013-01-01

    Background: Calendar time, age and duration are chronological objects. They represent an instant or a time period. Age and duration are usually expressed in units with varying lengths. The number of days in a month or a year depends on the position on the calendar. The units are also not homogeneous

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

    NARCIS (Netherlands)

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

    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

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

    NARCIS (Netherlands)

    Selm, van Martine; Heijden, van der 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 issue

  14. 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…

  15. Effects of zinc on the life span and reproductive capacity and the hereditability influence of D.melanogaster%锌对果蝇寿命及生殖力的影响及其可遗传性

    Institute of Scientific and Technical Information of China (English)

    毛雪; 郭欣欣; 张敏

    2012-01-01

    This paper is engaged in the study of zinc effects on the life span and reproduction capability and the hereditability influence of D. melanogaster. As is known, as a trace element, zinc has something to do with the enzyme structure and may act as an enzyme activator or regulator of the endocrine hormone participating in organism metabolism, such as that of protein, amino acid, nucleic acid, fat, carbohydrate, vitamin and other nutritious elements. Laboratory analysis shows that zinc can play an important role in skeletal development, reproduction, immune, biological membrane stability, and functions as a gene denominator, cell proliferator and differentiator. Therefore, zinc deficiency or excess in animal or human bodies may affect their growth, developmenl and reproduction. However, it is not clear how different concentration of zinc would affect the somatic longevity and reproduction capability under the experimental conditions, letting alone make sure if the effect can be hereditary. Therefore, we suggest using the fruit fly (Drosophila melanogaster) to sludy the life span and it? reproduction capability after zinc being treated by survival tests and statistical methods. In doing so, we have added zinc to the culture medium of parental Drosophila at a concentration of 0.026 g/L, 0.052 g/L, 0.104 g/L and 0.260 g/L. Then, the life span and reproduction capability of parental Drosophila after being treated with the first filial Drosophila untreated analyzed separately. The results show that zinc treatment at low concentrations (added to the culture medium at a concentration of 0.026 g/L, 0.052 g/L, 0.104 g/L) tends to extend the average life-span, middle life-span, maximum life-span and 90% lethal time in parental and the first filial Drosophila, with treatment of 0.052 g/L zinc showing the best significant effects. On the contrary, high dosage zinc treatment (0.260 g/L) tends to shorten the life-span of Drosophila significantly, and suppress their reproduction

  16. Leaf life span and nitrogen content in semideciduous forest tree species (Croton priscus and Hymenaea courbaril) Duração da vida da folha e conteúdo de nitrogênio em espécies arbóreas (Croton priscus e Hymenaea courbaril) de floresta semidecídua

    OpenAIRE

    Claudia Regina Baptista Haddad; Damiani Pereira Lemos; Paulo Mazzafera

    2004-01-01

    In comparison to deciduous species, evergreen plants have lower leaf nutrient contents and higher leaf life span, important mechanisms for nutrient economy, allowing the colonization of low fertility soils. Strategies to conserve nitrogen in two semideciduous tropical forest tree species, with different leaf life spans were analyzed. The hypothesis was the fact that the two species would present different nitrogen conservation mechanisms in relation to chemical (total nitrogen, protein, chlor...

  17. Late effects of selected immunosuppressants on immunocompetence, disease incidence, and mean life-span. I. Humoral immune activity. [Mice, x radiation

    Energy Technology Data Exchange (ETDEWEB)

    Perkins, E.H.; Peterson, W.J.; Gottlier, C.F.; Halsall, M.K.; Caccheiro, L.H.; Makinodan, T.

    1975-01-01

    The effect of different immunosuppressive treatments during young adulthood on humoral immune competence late in life was determined. It was found that the marked reduction in humoral immune competence in aged mice is further compromised when severe insults are administered early in life. Thus, thymectomy, splenectomy, and sublethal x-irradiation produced lasting immunodepression as measured in situ and by the hemolysin, direct and indirect plaque forming cells responses of adoptively transferred spleen cells. In contrast, treatment with cyclophosphamide and cortisone acetate were without effect, indicating that drug-damaged cells of the immune system were replaced by competent cells during the course of time. Decrease in immune competence of aged thymectomized animals could not be correlated with a decrease in numbers of theta-bearing T or immunoglobulin receptor-bearing B lymphocytes. The significance of the observed unequal effects of these immunosuppressants on immune competence, as they relate to disease incidence and life expectancy, are dealt with in the third paper in this series.

  18. CHRONOLOGICAL INVENTORY OF CHEMISTRY TEACHING

    OpenAIRE

    Laxman S. Bhattar; SWAMINATH L.BHATTAR

    2013-01-01

    The Chronological Research of Chemistry teaching in the science education isinvented by the following pioneer philosophers and they developed the skills abilitieswhich is remarked by the Greek philosophers are socrates and plato (in 116 to 127 BC)given an idea an naturalistic and conceptual thoughts and highlights on water. Chinaphilosophers (365 to 427 BC) Taoism made pioneer of Alchemy used in medicines andtranslation preparation of Au (Gold). Epicurea (341 to 371 to 400 BC) developed kinet...

  19. '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.

  20. The life-span of experimental animals and their progeny under influence of the ecological conditions in the Chernobyl zone of alienation

    International Nuclear Information System (INIS)

    Laboratory three-month old animals (white mongrel rats F0) were delivered to Chernobyl. The control animals were kept in a Kyiv vivarium. The indices of lifespan and dynamics of mortality of rats and their progeny have been determined using the life table methodology. The results have shown no essential difference in the indices of mortality and lifespan between control and experimental animals of the F0 generation. The expected lifespan of irradiated rats of the F1 - F2 generations increased in the age interval of 300 - 600 days. It's necessary to note that a decrease of this index in the Chernobyl groups of the F3 - F6 generations has been observed

  1. 火麻仁油及甾醇对家蚕寿命影响的观察%Observation of Influence of Semen Cannabis Oil and Sterol on Bombyx Mori Linnaeus Life-span

    Institute of Scientific and Technical Information of China (English)

    李寒冰; 孙静雅; 马永洁; 李根林; 任慧玲

    2012-01-01

    目的:观察火麻仁油及火麻仁甾醇对家蚕寿命的影响,探讨火麻仁油及甾醇的抗衰老作用.方法:取龄期相同、生长整齐的三眠蚕随机分为8组,即空白对照组,火麻仁油高、中、低剂量组,火麻仁甾醇高、中、低剂量组,维生素E对照组,每组110条.使用涂抹法将药液涂抹于新鲜桑叶上,4龄期内喂食3次,5龄期内喂食6次.结果:火麻仁油及甾醇高、中、低剂量组均对家蚕幼虫生存期较空白对照组明显延长(P<0.01或P<0.05),其中火麻仁甾醇能显著延长家蚕全生存期(P<0.01或P<0.05).与空白组相比,火麻仁油及甾醇均能显著延长5龄期家蚕耐饥饿时间(P<0.01).结论:火麻仁油及甾醇均能够延长家香各龄期生存期时间.%Objective:To observe the influence of Semen Cannabis oil and sterol on bombyx mori linnaeus life-span and discuss their anti-aging effect. Methods: Sanmian silkworm with the same age and growth were randomly divided into eight groups, namely blank control group, high, middle, low dose of Semen Cannabis oil group, high, meddle, low dose of Semen Cannabis oil and sterol group, positive control group. Physic liquor is daubed on the mulberry leaf ,3 times during 4 instars and 6 times during 5 instars. Results:The life-span of bombyx mori linnaeus larva was significantly longer in high, meddle, low dose of Semen Cannabis oil and sterol group compared with control group(P<0.01 or P<0.05). Semen Cannabis oil and sterol can significantly extend the all life span(P<0.01 or P<0.05). Compared with the blank control group, Semen Cannabis oil and sterol can significantly extend the hunger resistance time during 5 instars (P <0.01), Conclusion:both Semen Cannabis oil and sterol can extend the life span time of bombyx mori Linnaeus during any instars.

  2. CHRONOLOGICAL INVENTORY OF CHEMISTRY TEACHING

    Directory of Open Access Journals (Sweden)

    LAXMAN S. BHATTAR

    2013-05-01

    Full Text Available The Chronological Research of Chemistry teaching in the science education isinvented by the following pioneer philosophers and they developed the skills abilitieswhich is remarked by the Greek philosophers are socrates and plato (in 116 to 127 BCgiven an idea an naturalistic and conceptual thoughts and highlights on water. Chinaphilosophers (365 to 427 BC Taoism made pioneer of Alchemy used in medicines andtranslation preparation of Au (Gold. Epicurea (341 to 371 to 400 BC developed kineticand atomic theory. Nestorians-Arabian (800 to 900BC explains the translated literatureon Alchmey in to Arabic language. Jabiri Bn Hayyan (900to 969 to 1000 yearspublished book on Alchemy.

  3. Compatible spanning trees

    OpenAIRE

    Garcia Olaverri, Alfredo Martin; Huemer, Clemens; Hurtado Díaz, Fernando Alfredo; Tejel Altarriba, Francisco Javier

    2014-01-01

    Two plane geometric graphs are said to be compatible when their union is a plane geometric graph. Let S be a set of n points in the Euclidean plane in general position and let T be any given plane geometric spanning tree of S. In this work, we study the problem of finding a second plane geometric tree T' spanning S, such that is compatible with T and shares the minimum number of edges with T. We prove that there is always a compatible plane geometric tree T' having at most #n - 3#/4 edges in ...

  4. 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

  5. Chronology of eclipse "San Miao"

    Science.gov (United States)

    Liu, Ci-Yuan

    2001-06-01

    The ancient book "Mozi" (5th century BC) records: "In ancient times, the San Miao tribes were in disarray. The sun rose in the evening...King Yu vanquished them. "King Yu is a prehistoric person living in 23-19th century BC. The strange phenomena "sun rose in evening" was explained as a large solar eclipse at sunset by Pang. Therefore investigations on it may lead to an important progress of Chinese chronology. After an analysis on all similar records in Chinese history, we pay main attention to the relationship of eclipse computations with parameter "c", the long term of earth's rotation rate. We have computed all the solar eclipses in that period by the way similar to that used for investigating the "double dawn" eclipse. By change parameter "c" in reasonable range (28-36 sec/cy2), we have found 11 possible results listed in a table. One figure shows the eclipse maps and relative "double dawn/dusk" areas while another one illustrates how the parameter "c" affects the result. For an exact conclusion of King Yu's chronology, we need further progress from both side: history which may limit the King Yu's period and astronomy which may limit the possible range of parameter "c".

  6. 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)

    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

  7. 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.

  8. Chronology of early lunar crust

    Science.gov (United States)

    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.

  9. Astronomical arguments in Newton's Chronology

    CERN Document Server

    Naze, Yael

    2012-01-01

    In his Chronology, Newton uses astronomical "evidence" to support its extreme rejuvenation of ancient times. These elements, having a scientific varnish, provide some credibility to the work. They have been fiercely debated for a century, with a gradual undermining of Newton's assumptions. However, this has not dented the prestige of the English scientist. ----- Dans sa Chronologie, Newton utilise des "preuves" astronomiques pour appuyer son rajeunissement extreme des epoques anciennes. Ces elements, au vernis scientifique, donnent une credibilite certaine a l'ensemble. Ils ont donc ete aprement discutes, les debats sapant petit a petit les hypotheses du savant anglais pour finalement porter un coup mortel a l'ensemble. Cela n'a toutefois pas entame le prestige du savant anglais.

  10. 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

  11. Life span study report 11, part 1

    International Nuclear Information System (INIS)

    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 104 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.)

  12. 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…

  13. Life span study report 10 - 1

    International Nuclear Information System (INIS)

    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)

  14. Enhancing cognitive function across the life span.

    Science.gov (United States)

    Korol, Donna L

    2002-04-01

    Glucose administration regulates many neural and behavioral processes in rodents, including learning and memory. Given the important role of glucose in brain function and the safety of glucose as a treatment, we have investigated the effects of glucose administration in humans of different ages. In previous work, we examined the effects of early-morning glucose consumption on cognitive functions in elderly individuals. In this population, glucose enhanced performance on specific measures, particularly on those tasks where mild age-related deficits appear (e.g., verbal declarative memory). Interestingly, glucose failed to enhance cognitive functions in young adults. Our recent work has examined three issues related to glucose enhancement of cognition: First, is glucose effective only in reversing impairments or can it also facilitate performance in highly functioning individuals? Second, are glucose effects dependent either on time of day or on interactions with other meals? Third, are typical breakfast foods as effective as glucose in enhancing cognitive performance? Our findings suggest that glucose can improve memory in highly functioning populations as it does in populations with deficits. However, enhancement by glucose may require sufficient levels of task difficulty and of blood glucose. In addition, like glucose, early morning consumption of cereal can improve performance on some cognitive tests. These results have important implications for the nature of glucose facilitation of memory and for the role of dietary factors in performance of many daily activities. PMID:11976194

  15. Temperament and Generativity during the life span

    Directory of Open Access Journals (Sweden)

    Amelia Rizzo

    2013-05-01

    Full Text Available Abstract This review aimed to collect and discuss a variety of studies that utilized the Temperament and Chatacter Inventory (TCI, an instrument developed by Cloninger in 1993, based on his psychobiological model of temperament and character. Searching on PubMed, 26 from 828 researches has been selected on the basis of four criteria: (a articles published in English between 1993 and 2013 and identified as empirical or longitudinal studies; (b reaserches conducted in non pathological sample; (c measuring temperamental traits or dimensions with the TCI; (d regarding relevant topics to generativity. Implication for Temperament and character of couples and about the transmission of temperament from parents to children are pointed out. In conlcusion it can be said that TCI is a valid instrument that can describe and predict couples relationship and child temperament and character, until the late adulthood.

  16. Understanding Aggressive Behavior Across the Life Span

    OpenAIRE

    Liu, Jianghong; Lewis, Gary; Evans, Lois

    2012-01-01

    Aggressive behavior is the observable manifestation of aggression and is often associated with developmental transitions and a range of medical and psychiatric diagnoses across the lifespan. As healthcare professionals involved in the medical and psychosocial care of patients from birth through death, nurses frequently encounter—and may serve as—both victims and perpetrators of aggressive behavior in the workplace. While the nursing literature has continually reported research on prevention a...

  17. IS LIFE-SPAN UNDER OUR CONTROL??

    OpenAIRE

    Parle Milind; Bansal Nitin; Bansal Seema

    2011-01-01

    With each passing day, we age. Our body gets flooded with unwanted and deleterious elements, our cells lose their ability to divide, our nervous, endocrine and immune systems weaken with advancing age. Sagging skin, wrinkled face, graying hair, loss of muscle strength, reduced reflexes, low energy levels, increasing fat, faulty memory (dementia), weak immunity, impaired vision, defective hearing, decreased libido, cardiovascular problems and neurodegenerative disorders (like Parkinsonism and ...

  18. Over-expression of the catalytic core of mitochondrial DNA (mtDNA) polymerase in the nervous system of Drosophila melanogaster reduces median life span by inducing mtDNA depletion

    Science.gov (United States)

    Martínez-Azorín, Francisco; Calleja, Manuel; Hernández-Sierra, Rosana; Farr, Carol L.; Kaguni, Laurie S.; Garesse, Rafael

    2016-01-01

    DNA polymerase γ (pol γ) is the sole DNA polymerase devoted to mitochondrial DNA (mtDNA) replication. We have characterized the molecular and physiological effects of over-expression of the catalytic subunit of pol γ, pol γ-α, in the nervous system of Drosophila melanogaster using the upstream activation sequence (UAS)/yeast transcriptional activator by binding to UAS (GAL4) system. Tissue-specific over-expression of pol γ-α was confirmed by immunoblot analysis, whereas the very low levels of endogenous protein are undetectable in UAS or GAL4 control lines. The transgenic flies over-expressing pol γ-α in the nervous system showed a moderate increase in pupal lethality, and a significant decrease in the median life span of adult flies. Moreover, these flies displayed a decrease in the rate of synthesis of mtDNA, which is accompanied by a significant mtDNA depletion, and a corresponding decrease in the levels of mitochondrial transcription factor A (mtTFA). Biochemical analysis showed an oxidative phosphorylation (OXPHOS) defect in transgenic flies, which were more susceptible to oxidative stress. Although we did not detect apoptosis in the nervous system of adult transgenic flies, brains of larvae over-expressing pol γ-α showed evidence of increased cell death that correlates with the observed phenotypes. Our data establish an animal model that mimics some of the features of human mtDNA depletion syndromes. PMID:17999718

  19. A report from the 2013 international symposium: the evaluation of the effects of low-dose radiation exposure in the life span study of atomic bomb survivors and other similar studies.

    Science.gov (United States)

    Grant, E J; Ozasa, K; Ban, N; de González, A Berrington; Cologne, J; Cullings, H M; Doi, K; Furukawa, K; Imaoka, T; Kodama, K; Nakamura, N; Niwa, O; Preston, D L; Rajaraman, P; Sadakane, A; Saigusa, S; Sakata, R; Sobue, T; Sugiyama, H; Ullrich, R; Wakeford, R; Yasumura, S; Milder, C M; Shore, R E

    2015-05-01

    The RERF International Low-Dose Symposium was held on 5-6 December 2013 at the RERF campus in Hiroshima, Japan, to discuss the issues facing the Life Span Study (LSS) and other low-dose studies. Topics included the current status of low-dose risk detection, strategies for low-dose epidemiological and statistical research, methods to improve communication between epidemiologists and biologists, and the current status of radiological studies and tools. Key points made by the participants included the necessity of pooling materials over multiple studies to gain greater insight where data from single studies are insufficient; generating models that reflect epidemiological, statistical, and biological principles simultaneously; understanding confounders and effect modifiers in the current data; and taking into consideration less studied factors such as the impact of dose rate. It is the hope of all participants that this symposium be used as a trigger for further studies, especially those using pooled data, in order to reach a greater understanding of the health effects of low-dose radiation. PMID:25811153

  20. Spanning paths in hypercubes

    OpenAIRE

    Dvořák, Tomáš; Gregor, Petr; Koubek, Václav

    2005-01-01

    Given a family \\u_i,v_i\\_i=1^k of pairwise distinct vertices of the n-dimensional hypercube Q_n such that the distance of u_i and v_i is odd and k≤n-1, there exists a family \\P_i\\_i=1^k of paths such that u_i and v_i are the endvertices of P_i and \\V(P_i)\\_i=1^k partitions V(Q_n). This holds for any n≥2 with one exception in the case when n=k+1=4. On the other hand, for any n≥3 there exist n pairs of vertices satisfying the above condition for which such a family of spanning paths does not ex...

  1. 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...

  2. Mars chronology: assessing techniques for quantifying surficial processes

    Science.gov (United States)

    Doran, Peter T.; Clifford, Stephen M.; Forman, Steven L.; Nyquist, Larry; Papanastassiou, Dimitri A.; Stewart, Brian W.; Sturchio, Neil C.; Swindle, Timothy D.; Cerling, Thure; Kargel, Jeff

    2004-01-01

    Currently, the absolute chronology of Martian rocks, deposits and events is based mainly on crater counting and remains highly imprecise with epoch boundary uncertainties in excess of 2 billion years. Answers to key questions concerning the comparative origin and evolution of Mars and Earth will not be forthcoming without a rigid Martian chronology, enabling the construction of a time scale comparable to Earth's. Priorities for exploration include calibration of the cratering rate, dating major volcanic and fluvial events and establishing chronology of the polar layered deposits. If extinct andor extant life is discovered, the chronology of the biosphere will be of paramount importance. Many radiometric and cosmogenic techniques applicable on Earth and the Moon will apply to Mars after certain baselines (e.g. composition of the atmosphere, trace species, chemical and physical characteristics of Martian dust) are established. The high radiation regime may pose a problem for dosimetry-based techniques (e.g. luminescence). The unique isotopic composition of nitrogen in the Martian atmosphere may permit a Mars-specific chronometer for tracing the time-evolution of the atmosphere and of lithic phases with trapped atmospheric gases. Other Mars-specific chronometers include measurement of gas fluxes and accumulation of platinum group elements (PGE) in the regolith. Putting collected samples into geologic context is deemed essential, as is using multiple techniques on multiple samples. If in situ measurements are restricted to a single technique it must be shown to give consistent results on multiple samples, but in all cases, using two or more techniques (e.g. on the same lander) will reduce error. While there is no question that returned samples will yield the best ages, in situ techniques have the potential to be flown on multiple missions providing a larger data set and broader context in which to place the more accurate dates.

  3. The quantum physics of chronology protection

    OpenAIRE

    Visser, Matt

    2002-01-01

    This is a brief survey of the current status of Stephen Hawking's ``chronology protection conjecture''. That is: ``Why does nature abhor a time machine?'' I'll discuss a few examples of spacetimes containing ``time machines'' (closed causal curves), the sorts of peculiarities that arise, and the reactions of the physics community. While pointing out other possibilities, this article concentrates on the possibility of ``chronology protection''. As Stephen puts it: ``It seems that there is a Ch...

  4. A chronology of financial crises for Norway

    OpenAIRE

    Grytten, Ola Honningdal; Hunnes, Arngrim

    2010-01-01

    The paper offers a chronology of financial crises in Norway from her independence in 1814 till present times. Firstly, business cycles, covering almost two hundred years of economic history are mapped. These reveal years of crises in the real economy. These seem to coincide with most of the major financial crises. Secondly, the paper the financial crises are described chronologically. Thirdly, the paper investigates key patterns in credit and money volumes. It concludes that ma...

  5. Comparison of chronological and corrected ages in the gross motor assessment of low-risk preterm infants during the first year of life Comparação das idades cronológica e corrigida na avaliação motora grosseira de lactentes pré-termo com baixo risco no primeiro ano de vida

    Directory of Open Access Journals (Sweden)

    Ana Paula Restiffe

    2006-06-01

    Full Text Available OBJECTIVE: To evaluate the need of chronological age correction according to the degree of prematurity, when assessing gross motor development in preterm infants, during the first year of life. METHOD: Cohort, observational and prospective study. Alberta Infant Motor Scale (AIMS was used to evaluate 43 preterm infants with low risk for motor neurological sequelae, during the first year of corrected age. Mean scores were analyzed according to chronological and corrected ages. Children with motor neurological sequelae were excluded during follow-up. RESULTS: Gross motor mean scores in preterm infants tended to be higher when corrected age was used compared with those obtained when using chronological age, during the first twelve months. At thirteen months of corrected age, an overlapping of confidence intervals between corrected and chronological ages was observed, suggesting that from that period onwards correction for the degree of prematurity is no longer necessary. CONCLUSION: Corrected age should be used for gross motor assessment in preterm infants during the first year of life.OBJETIVO: Verificar a necessidade de corrigir a idade cronológica de acordo com o grau de prematuridade, na avaliação do desenvolvimento motor grosseiro em recém-nascidos pré-termo, durante o primeiro ano de vida. MÉTODO: Estudo coorte, observacional e prospectivo. A Escala Motora Infantil de Alberta (AIMS foi usada para avaliar 43 recém-nascidos pré-termos com baixo risco para lesão neurológica motora durante o primeiro ano de vida. A média dos escores foi analisada segundo as idades corrigidas e cronológicas. As crianças com seqüela motora neurológica foram excluídas durante o seguimento. RESULTADOS: A média dos escores do desenvolvimento motor grosseiro quando foi utilizada a idade corrigida tendeu a ser maior do que aqueles obtidos quando se utilizou a idade cronológica, durante os primeiros 12 meses. Aos 13 meses de idade corrigida, foi

  6. Towards an absolute chronology for the Aegean iron age: new radiocarbon dates from Lefkandi, Kalapodi and Corinth.

    Directory of Open Access Journals (Sweden)

    Michael B Toffolo

    Full Text Available The relative chronology of the Aegean Iron Age is robust. It is based on minute stylistic changes in the Submycenaean, Protogeometric and Geometric styles and their sub-phases. Yet, the absolute chronology of the time-span between the final stages of Late Helladic IIIC in the late second millennium BCE and the archaic colonization of Italy and Sicily toward the end of the 8(th century BCE lacks archaeological contexts that can be directly related to events carrying absolute dates mentioned in Egyptian/Near Eastern historical sources, or to well-dated Egyptian/Near Eastern rulers. The small number of radiocarbon dates available for this time span is not sufficient to establish an absolute chronological sequence. Here we present a new set of short-lived radiocarbon dates from the sites of Lefkandi, Kalapodi and Corinth in Greece. We focus on the crucial transition from the Submycenaean to the Protogeometric periods. This transition is placed in the late 11(th century BCE according to the Conventional Aegean Chronology and in the late 12(th century BCE according to the High Aegean Chronology. Our results place it in the second half of the 11(th century BCE.

  7. Towards an absolute chronology for the Aegean iron age: new radiocarbon dates from Lefkandi, Kalapodi and Corinth.

    Science.gov (United States)

    Toffolo, Michael B; Fantalkin, Alexander; Lemos, Irene S; Felsch, Rainer C S; Niemeier, Wolf-Dietrich; Sanders, Guy D R; Finkelstein, Israel; Boaretto, Elisabetta

    2013-01-01

    The relative chronology of the Aegean Iron Age is robust. It is based on minute stylistic changes in the Submycenaean, Protogeometric and Geometric styles and their sub-phases. Yet, the absolute chronology of the time-span between the final stages of Late Helladic IIIC in the late second millennium BCE and the archaic colonization of Italy and Sicily toward the end of the 8(th) century BCE lacks archaeological contexts that can be directly related to events carrying absolute dates mentioned in Egyptian/Near Eastern historical sources, or to well-dated Egyptian/Near Eastern rulers. The small number of radiocarbon dates available for this time span is not sufficient to establish an absolute chronological sequence. Here we present a new set of short-lived radiocarbon dates from the sites of Lefkandi, Kalapodi and Corinth in Greece. We focus on the crucial transition from the Submycenaean to the Protogeometric periods. This transition is placed in the late 11(th) century BCE according to the Conventional Aegean Chronology and in the late 12(th) century BCE according to the High Aegean Chronology. Our results place it in the second half of the 11(th) century BCE. PMID:24386150

  8. Effects of intrauterine infusion of Trueperella pyogenes on endometrial mRNA expression of proinflammatory cytokines and luteolytic cascade genes and their association with luteal life span in dairy cows.

    Science.gov (United States)

    Lima, F S; Greco, L F; Bisinotto, R S; Ribeiro, E S; Martinez, N M; Thatcher, W W; Santos, J E P; Reinhard, M K; Galvão, K N

    2015-11-01

    Objectives were to determine the effects of intrauterine infusion (IUI) of Trueperella pyogenes on endometrial expression of proinflammatory cytokines and luteal life span. Holstein cows (n = 32) were allocated randomly, in two replicates (15 then 17 cows), to receive one of three treatments on Day 5 of the estrous cycle: TP (n = 13), IUI containing 10(9) colony-forming units/mL of T. pyogenes; tumor necrosis factor (TNF; n = 9), IUI containing 1 μg of TNFα; and control (n = 10), IUI of saline solution. Five cows per treatment had uterine biopsies collected at 6, 12, and 24 hours after treatment to evaluate the endometrial messenger RNA expression of TNFα (TNF), interleukin-1β (IL1B), IL6, IL8, prostaglandin E synthase (PGES), prostaglandin F synthase (PGFS), and oxytocin receptor (OXR), and histologic evidence of inflammation. Messenger RNA expression was measured using quantitative reverse transcription polymerase chain reaction. The remaining cows had ovaries scanned and blood collected for progesterone evaluation; however, only seven, four, and three cows in the TP, TNF, and control groups were used for comparison in replicate 2. The GLIMMIX procedure of SAS was used for statistical analysis. All TP and TNF cows had moderate to severe endometrial inflammation, whereas only one control had mild inflammation. Premature luteolysis occurred in three, one, and zero cows in the TP, TNF and control groups, respectively. Delayed luteolysis occurred in one TP and one TNF cow. Interleukin-1β expression was greater in the TP cows than in the TNF cows at 24 hours after IUI. Moreover, IL6 expression tended to be greater for the TP cows than for the control cows at 12 hours after IUI. Interleukin 8 expression was greater in the TP cows than in the control and TNF cows at 24 hours after IUI. Oxytocin receptor expression tended to be greater for the TP cows and was greater for the TNF cows than for the control cows at 12 hours. The messenger RNA expressions of TNF, PGES

  9. Aging in elderly: Chronological versus photoaging

    Directory of Open Access Journals (Sweden)

    Priya Cinna Durai

    2012-01-01

    Full Text Available Background: Skin is a window to aging changes, a biological reality. There is a dearth of studies regarding the various chronological (intrinsic aging and photoaging (extrinsic changes seen in Asians. This study was undertaken to detect the clinical pattern of aging skin changes and dermatoses seen in the elderly. Materials and Methods: This was a descriptive study conducted on 500 consecutive elderly individuals attending the Dermatology out-patient department. The severity of photoaging was graded using Glogau scale. Results: Most of the population had skin type IV and V. Majority (415, 83% of our cases had chronological aging without photoaging and the remaining 85 (17% individuals had photoaging along with chronological aging. The common skin changes due to chronological aging were thin skin, fine wrinkles, xerosis, and loss of elasticity. Photoaging changes such as dyspigmentation, freckles, thick skin, deep wrinkles, melasma, citrine skin, senile purpura, pseudostellate scar, acrokeratoelastoidosis marginalis, and lentigines were less frequent in our study. Smoking and prolonged sun exposure was the risk factors aggravating photoaging. The most common dermatosis was pruritus in 248 (49.6% individuals, of which 149 (29.8% had pruritus associated with xerosis. Contact dermatitis was more common in males. Fungal infections were frequently seen in females. Seborrhoeic keratosis (253, 50.6% was the most common benign neoplasm more commonly seen in males. Cutaneous malignancies were less common in our study population. Conclusion: Photoaging changes were less common than chronological aging changes in skin type IV. Chronological changes were more frequent in females than males, while photoaging was more frequent in males.

  10. Tracking bacterial growth in liquid media and a new bacterial life model

    Institute of Scientific and Technical Information of China (English)

    刘实

    1999-01-01

    By increasing viscosity of liquid media above 8.4 centipoise (cp) i.e. 0.084 g·cm-1·S-1 individual growth and family formation of Escherichia coli was continuously observed in real-time for up to 6 h. The observations showed primarily unidirectional growth and reproduction of E. coli and suggested more than one reproduction in the observed portion of E. coli life span. A new bacterial life model is proposed: each bacterium has a stable cell polarity that ultimately transforms into two bacteria of different generations; the life cycle of a bacterium can contain more than one reproduction cycle; and the age of a bacterium should be defined by its experienced chronological time. This new bacterial life model differs from the dominant concepts of bacterial life but complies with all basic life principles based on direct observation of macroorganisms.

  11. Counting spanning trees in graphs

    OpenAIRE

    Azarija, Jernej

    2012-01-01

    The history of counting the number of spanning trees dates back into the year 1842 in which the German mathematician Gustav Kirchhoff derived a relation between the number of spanning trees of a graph G (τ(G)) and the determinant of a specific submatrix associated with G. After this result many other related results followed. For example in 1889 the British mathematician A. Cayley showed that the complete graph on n nodes has nn−2 spanning trees.The function τ can nowadays be found in the fi...

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

    International Nuclear Information System (INIS)

    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)

  13. Spanning Tree Based Attribute Clustering

    DEFF Research Database (Denmark)

    Zeng, Yifeng; Jorge, Cordero Hernandez

    2009-01-01

    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...

  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. PMID:26950210

  15. 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

  16. Chronology violation and the Cosmological Argument

    CERN Document Server

    Romero, G E

    2003-01-01

    The Kalam Cosmological Argument is perhaps the most solid and widly discussed argument for a caused creation of the universe. The usual objections to the argument mainly focus on the second premise. In this paper we discuss the dependency of the first premise on the topological structure of the space-time manifold adopted for the underlying cosmological model. It is shown that in chronology-violating space-times the first premise is also violated. The chronology-violation, in turn, requires a massive violation of the so-called energy conditions which could have observational effects that are briefly discussed here. Hence, astronomical observations could be relevant for the validity of the metaphysical argument. In this sense, it is possible to talk of "observational theology".

  17. The New Chronology of Iron Age Gordion

    OpenAIRE

    Aslan, Carolyn C.

    2013-01-01

    The Classical Review http://journals.cambridge.org/CAR Additional services for The Classical Review: Email alerts: Click here Subscriptions: Click here Commercial reprints: Click here Terms of use : Click here C.B. Rose, G. Darbyshire (edd.) The New Chronology of Iron Age Gordion. (Gordion Special Studies 6.) Pp. xiv + 181, gs, ills, maps. Philadelphia: University of Pennsylvania Museum of Archaeology and Anthropology, 2011. Cased, £45.50, US\\$69.95. ISBN:...

  18. 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.

  19. 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.

  20. Chronological Records of Li Anzhai and Yu Shiyu

    Institute of Scientific and Technical Information of China (English)

    WANG Hongliang

    2013-01-01

    In the history of Chinese ethnolo-gy, Li Anzhai and Yu Shiyu were not only life partners, but also an important academic married couple, especially in Tibetology.Li Anzhai was not only a representative in frontier research in China , but also a core figure in the West China school of Anthropology .He also has an important position in the history of modern academics . Yu Shiyu had an extremely rich talent for languages , and was good at sorting out bibliographies .Moreo-ver, she was interested in field investigation , which laid a solid foundation for her research on Tibetology .She also provided important support for Li Anzhai’ s fieldwork in Tibetan areas.The cou-ple ’ s academic life blended with each other , and they could be regarded as “two birds with the same destination” ( tianya tongming niao) . The life of this couple can help us understand that their life was both manifested and hidden from view by the times, and their academic life was both created and destroyed by the times .With regard to their academic position and social impact , it was a pity that their academic research did not meet the expectation of academic circles . Within various works related to the review of the history of the dis-ciplines, the couple was always included , in spite of the fact that the introductions to them were al-ways very simple .Although they are mentioned in some sporadic works , most of these works are only introductory articles or book reviews . Up until now, no one has systematically researched their life and academic thought .Hence, the author, by combing through various documents and archives , gives a chronological record of Li Anzhai ’ s and Yu Shiyu ’ s life story and academic achievements in order to provide basic historical data for academ-ic circles to carry out further research on the histo-ry of the discipline .

  1. Leaf life span and nitrogen content in semideciduous forest tree species (Croton priscus and Hymenaea courbaril Duração da vida da folha e conteúdo de nitrogênio em espécies arbóreas (Croton priscus e Hymenaea courbaril de floresta semidecídua

    Directory of Open Access Journals (Sweden)

    Claudia Regina Baptista Haddad

    2004-01-01

    Full Text Available In comparison to deciduous species, evergreen plants have lower leaf nutrient contents and higher leaf life span, important mechanisms for nutrient economy, allowing the colonization of low fertility soils. Strategies to conserve nitrogen in two semideciduous tropical forest tree species, with different leaf life spans were analyzed. The hypothesis was the fact that the two species would present different nitrogen conservation mechanisms in relation to chemical (total nitrogen, protein, chlorophyll, and proteolytic activity, functional (leaf life span, N-use efficiency, and N-resorption efficiency, morphological (specific leaf mass leaf characteristics, and total nitrogen in the soil. Hymenaea courbaril L. presented lower nitrogen compounds in leaves, longer leaf life span, higher N-use efficiency, and higher specific leaf mass, while absorbing proportionally less nitrogen from the soil than Croton priscus Croizat. These characteristics can contribute for a better nitrogen economy strategy of H. courbaril. No relationship was found between leaf life span and N resorption efficiency, nor between leaf life span, protease activity and nitrogen mobilization. The electrophoretic profiles of proteolytic enzymes in young leaves of the two species presented more bands with enzymatic activity than other kinds of leaves.Comparadas a espécies decíduas, as sempre-verdes têm menos nutrientes nas folhas, que também são mais longevas. Estes mecanismos são importantes para economia de nutrientes, e permitem a colonização de solos com baixa fertilidade. Foram analisadas estratégias de conservação de nitrogênio em duas espécies de floresta semidecídua, que aparentemente apresentavam longevidades foliares diferentes. Para isto foram comparados mecanismos químicos (concentrações de nitrogênio total, de proteína e clorofila e atividade proteolítica, funcionais (duração de vida das folhas, eficiência do uso de nitrogênio e eficiência de

  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...

  3. A Distributed Spanning Tree Algorithm

    DEFF Research Database (Denmark)

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

    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...

  4. 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

  5. SPANNING Between Structure and Nature

    OpenAIRE

    Gao, Yongmei

    2005-01-01

    The design project, a new student union building for the Virginia Tech campus is a 420-foot-long structure spanning from earth to water. Along a steel-glass bridge, three simple volumes play together to achieve the functions of the student union. There is an order among Nature, Architecture, and People in this project. Simple geometric forms and the elegant structure interact with nature to achieve the order. People animate the serenity and become the core of the poetic environment. ...

  6. KeySpan Energy Canada

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-09-01

    Operating in Alberta, KeySpan is a gas processing company with 14 gas plant facilities and pipelines in the province. Since its employees are sometimes working at remote locations, it has been difficult to use conventional classroom and seminar learning techniques to meet training needs. Cost-effective and innovative learning delivery solutions are now available from sophisticated information and communication technologies such as the Internet. In 1998, the Capability Development System (CDS) was developed by KeySpan as an on-line training system. It comprised a software assessment tool, a number of skills profiles for different occupations, and a curriculum registry providing technical information on the gas processing industry. E-learning initiatives are focused on specific projects or business units in order to better manage the training outcomes. The e-learning experience of KeySpan has resulted in benefits such as: better support to its customers and clients' needs through focused training on company-critical processes, services, products, and functions; more efficient employees; and, employees that feel part of the team.

  7. Hagedorn transition and chronology protection in string theory

    International Nuclear Information System (INIS)

    String theory is conjectured to be chronologically protected due to condensation of light winding states near closed null curves. Such condensation triggers a Hagedorn phase transition, whose end point is expected to have good chronology. We support this conjecture by studying strings in the Oplane orbifold, where we explicitly see winding states condensing in the pathological region of space-time. The string partition function has infrared divergences associated with the condensation and exhibits Hagedorn behavior, signaling at a phase transition. Contrary to common lore, chronology is protected through an infrared effect. (authors) Keywords: bad chronology, closed causal curves, winding strings, unstable modes, tachyon condensation, Hagedorn transition

  8. Criticism of traditional chronology: How long will Scaliger survive?

    Directory of Open Access Journals (Sweden)

    Bukvić Rajko

    2005-01-01

    Full Text Available The paper considers the problems of current state and survival of traditional chronology and history based upon the Scaliger and Petavius books from XVI and XVII centuries. Among many approaches that insist on the need of examination of that chronology, developed at first in Russia, but also in Germany, England, USA and other countries, author focuses to the investigation of Fomenko and his collaborators, but also the Khronotron group. Both these groups, like many others critics of current chronology, as their inspirators and predecessors mark Newton and Morozov, two great scientists who during many decades (! intensively considered problems of examination of chronology and history.

  9. Preliminary study of the chronology of the sedimentation process in lakes

    International Nuclear Information System (INIS)

    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)

  10. Preliminary study of the chronology of the sedimentation process in lakes

    Energy Technology Data Exchange (ETDEWEB)

    Patrocinio Junior, Antonio C.; Andrello, Avacir C., E-mail: juninhoska@hotmail.co, E-mail: acandrello@uel.b [Universidade Estadual de Londrina, PR (Brazil). Dept. de Fisica

    2009-07-01

    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)

  11. Geochemical alterations and chronology in archaeology

    International Nuclear Information System (INIS)

    Studies about hydrogen and fluorine incorporation in various materials used by the prehistoric man, bring to archaeological stratigraphies important information about chronology. Ion beams methods of analysis (such as AGLAE for the Louvre museum), provide depth resolution together with high detection sensitivity. They allow to pursue researches most often without sampling the artefacts. Some resonance nuclear reactions, such as produced by nitrogen 15 nucleus and protons, allow for measuring the concentration profile of fluorine and hydrogen present in the outer micrometer of the surface. Examples of the obsidian hydration and the fluorine penetration in flint or paleontological remains, show the interest of these methods to complement traditional methods of absolute dating. (author). 3 figs., 2 tabs., 34 refs

  12. Chronology of enstatite chondrites and ureilites

    International Nuclear Information System (INIS)

    This paper summarizes the chronological studies on enstatite chondrites and ureilites, both of which are special groups of meteorites with unknown origins. Two unequilibrated enstatite chondrites, Qingzhen and Yamato 6901 (E3), showed the highly disturbed Rb-Sr system, while their silicate fractions yielded the 2.1 Ga isochron. The thermally metamorphosed enstatite chondrite Khairpur (E6) showed the older Rb-Sr age of 4.50 Ga. The parent body of E3 chondrites experienced late thermal event at low temperature, which broke down alkali-bearing sulfides in E3. The observed Rb-Sr data are consistent with the mobilization of Rb from alkali-sulfide to silicate phases. Ureilites show highly depleted trace elements abundance which makes it difficult to determine the age of the formation. The U-Pb and Sm-Nd age determination of low-Ca ureilite Goalpara showed that the Pb and Nd isotopes are heavily contaminated with terrestrial components. The acid residues of high-Ca ureilite MET-78008 were free of contamination and defined the old U-Pb age of 4.563±0.006 Ga. The early formation of ureilites supports their formation through the collisional destruction of the parent body. Including the ureilite date, many evolved meteorites formed within the first 10 million years of the solar system history. Future studies on meteorite chronology with the purpose of understanding the early history of the solar system should focus on the fine time resolution through the precise U-Pb age determination or the relative age determination using the extinct nuclides with half lives less than 10 million years. (author)

  13. Time and Chronology: Conjoined Twins or Distant Cousins?

    Science.gov (United States)

    Blow, Frances; Lee, Peter; Shemilt, Denis

    2012-01-01

    Weaknesses in pupils' grasp of historical chronology are a commonplace in popular discussion of the state of history education. However, as Blow, Lee and Shemilt argue, although undoubtedly necessary and fundamental, mastery of chronological conventions is not sufficient: the difficulties that pupils experience when learning history are…

  14. 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…

  15. U. S. Military Documentary Films: A Chronological Analysis.

    Science.gov (United States)

    Avery, Robert K.; Larson, Timothy L.

    After presenting a chronological account of United States military documentary films from World War I through the Vietnam War, this paper reports on a study that compared the effectiveness of films prepared during World War II, the Korean War, and the Vietnam War. The first section, the chronological account, touches on such subjects as the…

  16. Changes in Anti-Mullerian 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, M.;

    2010-01-01

    Context: Anti-Mullerian hormone (AMH), which is secreted by immature Sertoli cells, triggers the involution of the fetal Mullerian ducts. AMH is 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......, and at 3 and 12 months), n = 55] and another group through puberty [(biannual measurements), n = 83]. Main Outcome Measures: Serum AMH was determined by a sensitive immunoassay. Serum testosterone, LH, and FSH were measured, and pubertal staging was performed in boys aged 6 to 20 yr (n = 616). Results...

  17. 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......, and at 3 and 12 months), n 55] and another group through puberty [(biannual measurements), n 83]. Main Outcome Measures: Serum AMH was determined by a sensitive immunoassay. Serum testosterone, LH, and FSH were measured, and pubertal staging was performed in boys aged 6 to 20 yr (n 616). Results: Serum...

  18. Spatial and Temporal Complexities of Current Great Plains Dunefield Chronological Data

    Science.gov (United States)

    Halfen, A. F.; Johnson, W. C.

    2012-12-01

    The North American Great Plains span nearly 2.8 million km2, of which nearly half is mantled by aeolian sediments (loess deposits, sand sheets, and dunefields). Stratigraphies of these sediments contain a rich history of late-Quaternary climate change, in particular aeolian dunefields, which provide a record of drought. During arid conditions in the Great Plains, stabilizing vegetation is diminished, leaving dunefields susceptible to aeolian erosion; during periods of increased moisture, conversely, vegetation re-establishes and dunefields stabilize. Using radiometric dating techniques, researchers can extract from the stratigraphy of dunefields the timing of past activity, and, therefore, periods of past drought. To date, more than 50 chronologies, comprised of over 700 ages, have established a detailed record of past dunefield activity in the Great Plains. Despite this extensive dataset, correlating periods of past droughts across the region remains problematic, in large part due to the spatial and temporal limitations in the data. In this poster, we present a spatial and temporal synthesis of current Great Plains dunefield chronologies, followed by an analysis of the complexities of these data, in particular when used to determine periods of past drought. To illustrate these complexities, we present a bicentennial, 1 x 1 degree gridded model of dune activity (e.g., active, stable, no data) spanning the last 2000 years. Our model clearly illustrates gaps in spatial coverage and temporal biases of chronologies. To further highlight the complexities of using current Great Plains datasets as proxies for prehistoric drought, we compare a 2.5 x 2.5 degree gridded model of dune activity during the Medieval Climatic Anomaly (A.D. 1000-1400) and historic time (A.D. 1800-2000) to Palmer Drought Severity Index (PDSI)-reconstructed droughts for the same time intervals. In general, dunefield activity is in good agreement with PDSI-reconstructed drought, however, unlike tree

  19. Octave-spanning semiconductor laser

    CERN Document Server

    Rösch, Markus; Beck, Mattias; Faist, Jérôme

    2014-01-01

    We present here a semiconductor injection laser operating in continuous wave with an emission covering more than one octave in frequency, and displaying homogeneous power distribution among the lasing modes. The gain medium is based on a heterogeneous quantum cascade structure operating in the THz range. Laser emission in continuous wave takes place from 1.64 THz to 3.35 THz with optical powers in the mW range and more than 80 modes above threshold. Free-running beatnote investigations on narrow waveguides with linewidths of 980 Hz limited by jitter indicate frequency comb operation on a spectral bandwidth as wide as 624 GHz, making such devices ideal candidates for octave-spanning semiconductor-laser-based THz frequency combs.

  20. Spanning Trees in Random Satisfiability Problems

    OpenAIRE

    Ramezanpour, A.; Moghimi-Araghi, S.

    2005-01-01

    Working with tree graphs is always easier than with loopy ones and spanning trees are the closest tree-like structures to a given graph. We find a correspondence between the solutions of random K-satisfiability problem and those of spanning trees in the associated factor graph. We introduce a modified survey propagation algorithm which returns null edges of the factor graph and helps us to find satisfiable spanning trees. This allows us to study organization of satisfiable spanning trees in t...

  1. 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.

  2. Luminescence chronologies for sediments recording paleoseismic events and slip rate for the central Garlock fault, California, USA

    Science.gov (United States)

    Okubo, S. G.; Wolf, E.; Roder, B. J.; Rhodes, E. J.; McGill, S. F.; Dolan, J. F.; Mcauliffe, L. J.; Lawson, M. J.; Barrera, W. A.

    2012-12-01

    Luminescence dating has a significant role to play in providing chronological control for lacustrine and alluvial sediments that record both tectonic and climatic events. However, poor characteristics in some environments mean that the well-established method of OSL (optically stimulated luminescence) dating of quartz is not well-suited for the material available. In order to overcome this significant limitation, a range of methods based on the IRSL (infra-red stimulated luminescence) and ITL (isothermal thermoluminescence) of K-feldspar are currently under development. The site of El Paso Peaks, California has an established C-14 chronology spanning the last 7,000 years for a series of playa sediments comprising silts and fine sands, with occasional incursions of coarser sands and gravels from the alluvial fan that forms one side of the small ephemeral lake basin. Another barrier is formed by a shutter ridge of the left-lateral central Garlock fault, and this succession of sediments records at least six seismic events. Following collection of a suite of 24 luminescence samples distributed throughout the upper part of this succession, this site provides a rare opportunity to test different luminescence dating protocols in a rigorous fashion. At the site of Christmas Canyon West, a few miles further east, numerous small offsets of depositional and erosional alluvial fan features provide the opportunity to determine slip rates for a variety of timescales spanning the past couple of thousand years, besides forming a record of the timing of several discrete depositional episodes representing local high precipitation events. We review the challenges involved in developing a reliable luminescence chronology for sediment deposition in these contexts, and in relating this chronology to significant environmental events.

  3. 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.

  4. Chronology of mitochondrial and cellular events during skeletal muscle ischemia-reperfusion.

    Science.gov (United States)

    Paradis, Stéphanie; Charles, Anne-Laure; Meyer, Alain; Lejay, Anne; Scholey, James W; Chakfé, Nabil; Zoll, Joffrey; Geny, Bernard

    2016-06-01

    Peripheral artery disease (PAD) is a common circulatory disorder of the lower limb arteries that reduces functional capacity and quality of life of patients. Despite relatively effective available treatments, PAD is a serious public health issue associated with significant morbidity and mortality. Ischemia-reperfusion (I/R) cycles during PAD are responsible for insufficient oxygen supply, mitochondriopathy, free radical production, and inflammation and lead to events that contribute to myocyte death and remote organ failure. However, the chronology of mitochondrial and cellular events during the ischemic period and at the moment of reperfusion in skeletal muscle fibers has been poorly reviewed. Thus, after a review of the basal myocyte state and normal mitochondrial biology, we discuss the physiopathology of ischemia and reperfusion at the mitochondrial and cellular levels. First we describe the chronology of the deleterious biochemical and mitochondrial mechanisms activated by I/R. Then we discuss skeletal muscle I/R injury in the muscle environment, mitochondrial dynamics, and inflammation. A better understanding of the chronology of the events underlying I/R will allow us to identify key factors in the development of this pathology and point to suitable new therapies. Emerging data on mitochondrial dynamics should help identify new molecular and therapeutic targets and develop protective strategies against PAD. PMID:27076618

  5. 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.

  6. Chronological changes in hypertensive intracerebral hemorrhages

    International Nuclear Information System (INIS)

    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

  7. Gamma spectrometry for chronology of recent sediments

    International Nuclear Information System (INIS)

    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). 210Pb, 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 210Pb as a tracer it is necessary to determine its excess portion, which is not supported by ingrowth from the parent nuclide 226Ra. Its analysis is mostly performed via short lived daughter isotopes that follow after the intermediate gaseous member 222Rn. Preventing the escape of radon from the sample is a critical step before analysis due to a negative effect of supported 210Pb underestimation on the chronology, which was also documented in this thesis. Time series registering ingrowth of 214Pb and 214Bi towards radioactive equilibrium with 226Ra in different containers were evaluated for analyses of 226Ra. Direct analyses of 226Ra 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 multicorer cores

  8. 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

  9. 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.

  10. 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

  11. Differentiation of Cognitive Abilities across the Life Span

    Science.gov (United States)

    Tucker-Drob, Elliot M.

    2009-01-01

    Existing representations of cognitive ability structure are exclusively based on linear patterns of interrelations. However, a number of developmental and cognitive theories predict that abilities are differentially related across ages (age differentiation-dedifferentiation) and across levels of functioning (ability differentiation). Nonlinear…

  12. Measuring Replicative Life Span in the Budding Yeast

    OpenAIRE

    Steffen, Kristan K.; Kennedy, Brian K.; Kaeberlein, Matt

    2009-01-01

    Aging is a degenerative process characterized by a progressive deterioration of cellular components and organelles resulting in mortality. The budding yeast Saccharomyces cerevisiae has been used extensively to study the biology of aging, and several determinants of yeast longevity have been shown to be conserved in multicellular eukaryotes, including worms, flies, and mice 1. Due to the lack of easily quantified age-associated phenotypes, aging in yeast has been assayed almost exclusively by...

  13. Assessing Executive Functions: A Life-Span Perspective

    Science.gov (United States)

    Reynolds, Cecil R.; Horton, Arthur MacNeill, Jr.

    2008-01-01

    Despite many disagreements on the utility of neuropsychological applications in schools, executive function measures have been found to be useful across a variety of areas and ages. In addition, many disagreements are extant in discussions of the maturational course of the development of executive functioning abilities that are dependent on…

  14. Meditation improves self-regulation over the life span

    OpenAIRE

    Tang, Yi-Yuan; Posner, Michael I.; Rothbart, Mary K.

    2013-01-01

    The use of meditation to improve emotion and attention regulation has a long history in Asia and there are many practitioners in Western countries. Much of the evidence on the effectiveness of meditation is either anecdotal or a comparison of long-term meditators with controls matched in age and health. Recently, it has been possible to establish changes in self-regulation in undergraduate students after only 5 days of meditation practice, allowing randomized trials comparing effects of medit...

  15. 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.

    , northern Indian Ocean. Jour. Foram. Res. 27: 5-19. Hemleben, Ch., Spindler, M. and Anderson, O.R. 1989. Modern Planktonic Foraminifera. Springer-Verlag, New York Inc.. Houstan, R.M., Huber, B.T. and Spero, H.J. 1999. Size-related isotopic trends in some...

  16. Facial affect recognition across the adult life span

    OpenAIRE

    MOOSAVIAN, Elham; BORRY, Fatemeh

    2015-01-01

    Introduction: The results of the researches have shown expression and recognition of emotion are two of the basic skills on which normal social interaction is based. As people grow older, they may become wiser and more experienced in interacting with other people, but they can also experience memory loss and cognitive slow-down, influencing the quality of relations in their daily routines. Experimental studies indicate that facial affect recognition, particularly negative emotions, decreases ...

  17. Colour Constancy Across the Life Span: Evidence for Compensatory Mechanisms

    OpenAIRE

    Sophie Wuerger

    2013-01-01

    It is well known that the peripheral visual system declines with age: the yellowing of the lens causes a selective reduction of short-wavelength light and sensitivity losses occur in the cone receptor mechanisms. At the same time, our subjective experience of colour does not change with age. The main purpose of this large-scale study (n = 185) covering a wide age range of colour-normal observers (18-75 years of age) was to assess the extent to which the human visual system is able to compensa...

  18. 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. PMID:26479015

  19. Nature over nurture: temperament, personality, and life span development.

    Science.gov (United States)

    McCrae, R R; Costa, P T; Ostendorf, F; Angleitner, A; Hrebícková, M; Avia, M D; Sanz, J; Sánchez-Bernardos, M L; Kusdil, M E; Woodfield, R; Saunders, P R; Smith, P B

    2000-01-01

    Temperaments are often regarded as biologically based psychological tendencies with intrinsic paths of development. It is argued that this definition applies to the personality traits of the five-factor model. Evidence for the endogenous nature of traits is summarized from studies of behavior genetics, parent-child relations, personality structure, animal personality, and the longitudinal stability of individual differences. New evidence for intrinsic maturation is offered from analyses of NEO Five-Factor Inventory scores for men and women age 14 and over in German, British, Spanish, Czech, and Turkish samples (N = 5,085). These data support strong conceptual links to child temperament despite modest empirical associations. The intrinsic maturation of personality is complemented by the culturally conditioned development of characteristic adaptations that express personality; interventions in human development are best addressed to these. PMID:10653513

  20. Nasal trigeminal chemosensitivity across the adult life span

    Czech Academy of Sciences Publication Activity Database

    Wysocki, C. J.; Cowart, B. J.; Radil, Tomáš

    2003-01-01

    Roč. 65, č. 1 (2003), s. 115-122. ISSN 0031-5117 Grant ostatní: NI on Deafness (US) P50 DC00214; NI on Deafness (US) RO1 DC00298; Fogarty Center(US) F05 TW04839; Garfield Foundation(US) x Institutional research plan: CEZ:AV0Z5011922 Keywords : chemesthesis * trigeminal Subject RIV: FH - Neurology Impact factor: 1.856, year: 2003

  1. Spans in 2-Categories: A monoidal tricategory

    CERN Document Server

    Hoffnung, Alexander E

    2011-01-01

    We present Trimble's definition of a tetracategory and prove that the spans in (strict) 2-categories with certain limits have the structure of a monoidal tricategory, defined as a one-object tetracategory. We recall some notions of limits in 2-categories for use in the construction of the monoidal tricategory of spans.

  2. 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.

  3. Node degree distribution in spanning trees

    International Nuclear Information System (INIS)

    A method is presented for computing the number of spanning trees involving one link or a specified group of links, and excluding another link or a specified group of links, in a network described by a simple graph in terms of derivatives of the spanning-tree generating function defined with respect to the eigenvalues of the Kirchhoff (weighted Laplacian) matrix. The method is applied to deduce the node degree distribution in a complete or randomized set of spanning trees of an arbitrary network. An important feature of the proposed method is that the explicit construction of spanning trees is not required. It is shown that the node degree distribution in the spanning trees of the complete network is described by the binomial distribution. Numerical results are presented for the node degree distribution in square, triangular, and honeycomb lattices. (paper)

  4. Performance, Career Dynamics, and Span of Control

    DEFF Research Database (Denmark)

    Smeets, Valerie Anne Rolande; Waldman, Michael; Warzynski, Frederic Michel Patrick

    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 this......’s predictions concerning span of control including predictions derived from the learning component of the model. Overall, our investigation supports the notion that the scale-of-operations effect and additionally learning are important determinants of the internal organization of firms including span of control....

  5. 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...

  6. Spanning and independence properties of frame partitions

    CERN Document Server

    Bodmann, Bernhard G; Paulsen, Vern I; Speegle, Darrin

    2010-01-01

    We answer a number of open problems in frame theory concerning the decomposition of frames into linearly independent and/or spanning sets. We prove that in finite dimensional Hilbert spaces, Parseval frames with norms bounded away from 1 can be decomposed into a number of sets whose complements are spanning, where the number of these sets only depends on the norm bound. We also prove, assuming the Kadison-Singer conjecture is true, that this holds for infinite dimensional Hilbert spaces. Further, we prove a stronger result for Parseval frames whose norms are uniformly small, which shows that in addition to the spanning property, the sets can be chosen to be independent, and the complement of each set to contain a number of disjoint, spanning sets.

  7. 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 ...

  8. Experimental study of single span railway bridges

    OpenAIRE

    Rigueiro, Constança; Rebelo, C.; Silva, L. Simões da

    2007-01-01

    The main purpose of this paper is to present some results concerning the investigation that has been done by the authors regarding the dynamic response of small to médium span railway bridges using response acceleration data colleted during the measurements carried out on single span bridges on the railway track Linz-Wels, in Austria. Using output-only methods in this experimental program, it was possible to have an estimation of the igenfrequencies, mode shapes and the corresponding viscous ...

  9. Reduced span spray – Part 1: Retention

    OpenAIRE

    Massinon, Mathieu; De Cock, Nicolas; Ouled Taleb Salah, Sofiene; Lebeau, Frédéric

    2016-01-01

    Maximising treatment efficiency for a given target lies mainly on depositing a maximum part of the spray volume within an optimal droplet size range, which has to be as narrow as possible to reduce retention variability and drift issues. The present work focuses on exploring the effect of span factor of the droplet size distribution on the final retention by a 3D target plant using a modelling approach with the final aim of guiding the development of a reduced span nozzle (Redu...

  10. Coexistence of spanning clusters in directed percolation

    OpenAIRE

    Sen, Parongama; Bhattacharjee, Somendra M.

    1998-01-01

    The probability distribution for the number of top to bottom spanning clusters in Directed percolation in two and three dimensions appears to be universal and is of the form $P(n) \\sim \\exp(-\\alpha n^2)$. We argue that $\\alpha$ is a new critical quantity vanishing at the upper critical dimension. The probability distribution of the individual masses of the spanning clusters is found to have a Pearson distribution with a lower cutoff. Various properties of the clusters are reported.

  11. 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...... 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....

  12. Ranking and Ordering Problems of Spanning Trees

    OpenAIRE

    Baumgart, Matthias

    2010-01-01

    In this thesis, we study bispanning graphs, i.e., graphs whose edge set consists of two disjoint spanning trees. In particular, we analyze this graph class with respect to a conjecture due to Mayr and Plaxton. In simple terms, this conjecture states that there exists a minimum number of spanning tree with distinct weights required that the weight function fulfills predefined properties. We are able to prove this claim for certain subclasses of all weighted bispanning graphs. Based on these fi...

  13. Recent advances in long-term climate and moisture reconstructions from the Baltic region: Exploring the potential for a new multi-millennial tree-ring chronology

    Science.gov (United States)

    Edvardsson, Johannes; Corona, Christophe; Mažeika, Jonas; Pukienė, Rutile; Stoffel, Markus

    2016-01-01

    This study presents the first results from an ongoing initiative to develop a multi-millennial Baltic tree-ring width (TRW) chronology consisting of 12 floating records from subfossil Scots pines (Pinus sylvestris L.) extracted from three Lithuanian peat-mining areas. The floating series have been complemented with absolutely dated TRW chronologies which were obtained from living trees growing in unmanaged and unexploited peatland areas adjacent to each of the above study sites. The subfossil material has been dated by radiocarbon and shows a temporal spread over the last 6000 years, with assemblages of trees during the Holocene Thermal Maximum (HTM; 8000-4000 BP) and the onset of the Medieval Warm Period (MWP, AD 900-1350). Annual tree growth and sample replication of peatland pines reflect moisture variations and long-term climate variability. The importance of extending the TRW chronologies should not therefore be underestimated as (1) climate records of comparable length and resolution do not exist for the Baltic region, but also as (2) a result of a widespread lack of detailed moisture proxies spanning several millennia. Our data clearly show that a 6000-yr, continuous pine chronology from the Baltic region is a realistic objective, and would doubtlessly fill a major geographic gap in an ecologically sensitive region located at the interface between the temperate and boreal vegetation zones.

  14. London SPAN version 4 parameter file format

    International Nuclear Information System (INIS)

    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

  15. Nurturing Children's Concepts of Time and Chronology through Literature

    Science.gov (United States)

    Harms, Jeanne McLain; Lettow, Lucille J.

    2007-01-01

    Time is an emerging concept during childhood. At first, children's concept of time is rather vague. Banks and Banks suggest that the goal for teaching time concepts and chronology in the elementary and middle school years should be to nurture students' ability to understand and interpret time concepts and comprehend how past and present events are…

  16. Aspects of the Weichselian chronology In central East Greenland

    DEFF Research Database (Denmark)

    Funder, Svend Visby; Hjort, Christian

    1973-01-01

    From central East Greenland, CH ages between 19,500 - >40,000 years B.P. have been obtained for six samples of marine bivalve shells. The ages seem to be consistent with geological observations and form the basis for a tentative chronology for the vVeichselian ice age in the region. It appears that...

  17. Behavior of three-span braced columns with equal and unequal spans

    OpenAIRE

    Yang, Yu-Wen

    1993-01-01

    Columns with three spans separated by elastic braces are analyzed. The influences of translational and rotational resistance at the braces, various end conditions, and the bracing locations for the perfect columns with equal and unequal spans subjected to uniform and nonuniform axial load are investigated. For imperfect columns with equal or unequal spans subjected to uniform compression, the effects of various end conditions at the top and various initial deflections are studied. "Ide...

  18. The chronology of mangrove swamps of Hadi, Maharashtra, using luminescence dating techniques

    International Nuclear Information System (INIS)

    Mangrove, the plant life associated with the near shore marine habitat, lies in a transitional zone between the marine and terrestrial environments of the low-lying tropical coastlines. The hydrology of this coastal ecosystem is balanced by the tidal amplitude and fresh water input. Study of the temporal changes within the environmental settings of mangroves and its chronology forms an important aspect of any coastal geological programmes. As such, this information could be useful in initiating corrective measures in maintaining the mangroves. Keeping this view in mind, a chronological control for the mangrove profile of Hadi, Malwan, Maharashtra was obtained using Blue Light Stimulated Luminescence (BLSL) to ascertain the paleological reconstruction in the region. Due to the heavy precipitation rates in the region, the samples collected at various depths up to 100 cm were observed to have high moisture contents. Taking this in to account for evaluation of annual dose rate, four samples were dated using BLSL techniques. The ages of the samples were found to be between 1.58 - 5.45 ka. The description of mangroves, their ecological importance, method of dating and the implication thereof are discussed in the paper. (author)

  19. Artificial life, the new paradigm

    International Nuclear Information System (INIS)

    A chronological synthesis of the most important facts is presented in the theoretical development and computational simulation that they have taken to the formation of a new paradigm that is known as artificial life; their characteristics and their main investigation lines are analyzed. Finally, a description of its work is made in the National University of Colombia

  20. Boundary Spanning in Global Software Development

    DEFF Research Database (Denmark)

    Søderberg, Anne-Marie; Romani, Laurence

    How does a global company deal with inter-organizational boundary spanning activities? If the company is an Indian vendor, and the client a Western multinational company in need of major transformations, the answer to this question challenges prior research. This paper builds on a field study 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. Spanning Forests and the Golden Ratio

    OpenAIRE

    Chebotarev, Pavel

    2006-01-01

    For a graph G, let f_{ij} be the number of spanning rooted forests in which vertex j belongs to a tree rooted at i. In this paper, we show that for a path, the f_{ij}'s can be expressed as the products of Fibonacci numbers; for a cycle, they are products of Fibonacci and Lucas numbers. The {\\em doubly stochastic graph matrix} is the matrix F=(f_{ij})/f, where f is the total number of spanning rooted forests of G and n is the number of vertices in G. F provides a proximity measure for graph ve...

  2. 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...

  3. Boundary Spanning Leadership Practices for Population Health.

    Science.gov (United States)

    Shirey, Maria R; White-Williams, Connie

    2015-09-01

    This department highlights change management strategies that may be successful in strategically planning and executing organizational change initiatives. In this article, the authors discuss boundary spanning leadership practices for achieving the Triple Aim of simultaneously improving the health of populations, improving the patient experience, and reducing per-capita cost of health care. Drawing on experience with an existing population-focused heart failure clinic borne of an academic-practice partnership, the authors discuss boundary spanning leadership practices aimed at achieving the Triple Aim concept and its intended design. PMID:26301546

  4. Impounding Experimental Research of Large Span Aqueduct

    OpenAIRE

    Huafeng Deng; Min Zhu; Xianfan Yuan; Qian Luo

    2013-01-01

    In this study, we have a research of the impounding experimental research of large span aqueduct. Caohe aqueduct is the mark building of the middle line of the South-to-North Water Diversion Project, of which the span is 30m. For this aqueduct, the structure is relatively complicated with great technical difficulties, what’s more there's no engineering experience or theoretical method to provide reference in domestic and abroad. It can be seen clear that whether the actual stressing state, de...

  5. 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...

  6. A Survey of the Xia-Shang-Zhou Chronology Project

    Institute of Scientific and Technical Information of China (English)

    Xi Zezong

    2002-01-01

    @@ Ⅰ. Goals In connection with the history of science, the XiaShang-Zhou Chronology Project is one of the important projects of the National Key Science and Technology Research and Development Programme of the Ninth Five-Year Plan. It officially began in May 1996.After five years of effort by more than 200 scholars and experts from the Chinese Academy of Sciences,the Chinese Academy of Social Sciences, Peking University and other institutions, the project has attained its goal. The general goal of the project is to establish a chronological table for the three dynasties by means of combining the humanities and social sciences with the natural sciences. The concrete goals for different historical periods are:

  7. 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.

  8. Asbestos: a chronology of its origins and health effects.

    OpenAIRE

    Huncharek, M

    1990-01-01

    The emotionalised subject of asbestos is treated in chronological terms: how the "magic mineral" known in ancient times in Europe and Asia became in the late nineteenth century an important industrial resource of particular interest to the navies of the world; and how its malign effects gradually became apparent during the present century. The media have made asbestos a notorious villain, but it still has properties and applications useful to society if they are properly controlled in the sam...

  9. REVIEW: South & East Asian Adult Education: Chronologies in Commonwealth Countries

    OpenAIRE

    SHARMA, Reviewed By Dr. Ramesh C.

    2002-01-01

    The major aim of this international research project was to record and analyze the chronological development of adult education in the country members of the commonwealth. It traces the developments in the area of adult education since early 1900s to the very latest as for 1999. This project was supported by the Commonwealth of Learning; the Ontario Institute for Studies in Education, University of Toronto; the Commonwealth Association for the Education and Training of Adults; and the United ...

  10. The Chronology of Third Molar Eruption in the Croatian Population

    OpenAIRE

    Brkić, Hrvoje; Vodanović, Marin; Dumančić, Jelena; Lovrić, Željka; Čuković-Bagić, Ivana; Petrovečki, Mladen

    2011-01-01

    Dental age estimation is common in orthodontics, paedodontics, paleodontology and forensic dentistry. The aim of this study was to assess chronological course of eruptive developmental phases of third molar and to establish parameters for the Croatian population. Sample of this study consisted of 1249 orthopantomograms of 530 (42.4%) male and 719 (57.6%) female subjects, aged 10 to 25 years. Eruptive phases were classified in 4 stages. No significant sex difference was found. Esta...

  11. SPAN C - Terminal sterilization process analysis program

    Science.gov (United States)

    1969-01-01

    Computer program, SPAN-C, measures the dry heat thermal sterilization process applied to a planetary capsule and calculates the time required for heat application, steady state conditions, and cooling. The program is based on the logarithmic survival of micro-organisms. Temperature profiles must be input on cards.

  12. SPAN - Terminal sterilization process analysis program

    Science.gov (United States)

    1969-01-01

    Computer program, SPAN, measures the dry heat thermal sterilization process applied to a planetary capsule and calculates the time required for heat application, steady state conditions, and cooling. The program is based on the logarithmic survival of micro-organisms. Temperature profiles must be input on tape.

  13. Construction Technology of Long Span Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    2000-01-01

    A large variety of construction methods are used during construction of major bridges, and in many cases the final structural system must be chosen with due respect to the construction process. Today the preferred construction methods are: the free-cantilever method, the launching method and the ...... full-span erection method....

  14. Computing Minimum Diameter Color-Spanning Sets

    Science.gov (United States)

    Fleischer, Rudolf; Xu, Xiaoming

    We study the minimum diameter color-spanning set problem which has recently drawn some attention in the database community. We show that the problem can be solved in polynomial time for L 1 and L ∞ metrics, while it is NP-hard for all other L p metrics even in two dimensions. However, we can efficiently compute a constant factor approximation.

  15. Dentulous Appliance for Upper Anterior Edentulous Span

    OpenAIRE

    Chalakkal, Paul; Devi, Ramisetty Sabitha; Srinivas, G Vijay; Venkataramana, Pammi

    2013-01-01

    This article discusses about a fixed dentulous appliance that was constructed to replace the primary upper anterior edentulous span in a four year old girl. It constituted a design, whereby the maxillary primary second molars were used to support the appliance through bands and a wire that contained an acrylic flange bearing trimmed acrylic teeth, anteriorly. The appliance was functionally and aesthetically compliant.

  16. Effect of high dose irradiation on the red cell span in rabbits

    International Nuclear Information System (INIS)

    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 60Co 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 51Cr. (Author)

  17. K-Ar chronological study of the quaternary volcanic activity in Shin-etsu Highland

    International Nuclear Information System (INIS)

    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. A novel web-based TinT application and the chronology of the Primate Alu retroposon activity

    Directory of Open Access Journals (Sweden)

    Makałowski Wojciech

    2010-12-01

    Full Text Available Abstract Background DNA sequences afford access to the evolutionary pathways of life. Particularly mobile elements that constantly co-evolve in genomes encrypt recent and ancient information of their host's history. In mammals there is an extraordinarily abundant activity of mobile elements that occurs in a dynamic succession of active families, subfamilies, types, and subtypes of retroposed elements. The high frequency of retroposons in mammals implies that, by chance, such elements also insert into each other. While inactive elements are no longer able to retropose, active elements retropose by chance into other active and inactive elements. Thousands of such directional, element-in-element insertions are found in present-day genomes. To help analyze these events, we developed a computational algorithm (Transpositions in Transpositions, or TinT that examines the different frequencies of nested transpositions and reconstructs the chronological order of retroposon activities. Results By examining the different frequencies of such nested transpositions, the TinT application reconstructs the chronological order of retroposon activities. We use such activity patterns as a comparative tool to (1 delineate the historical rise and fall of retroposons and their relations to each other, (2 understand the retroposon-induced complexity of recent genomes, and (3 find selective informative homoplasy-free markers of phylogeny. The efficiency of the new application is demonstrated by applying it to dimeric Alu Short INterspersed Elements (SINE to derive a complete chronology of such elements in primates. Conclusion The user-friendly, web-based TinT interface presented here affords an easy, automated screening for nested transpositions from genome assemblies or trace data, assembles them in a frequency-matrix, and schematically displays their chronological activity history.

  19. Octave Spanning Frequency Comb on a Chip

    CERN Document Server

    Del'Haye, P; Gavartin, E; Holzwarth, R; Kippenberg, T J

    2009-01-01

    Optical frequency combs have revolutionized the field of frequency metrology within the last decade and have become enabling tools for atomic clocks, gas sensing and astrophysical spectrometer calibration. The rapidly increasing number of applications has heightened interest in more compact comb generators. Optical microresonator based comb generators bear promise in this regard. Critical to their future use as 'frequency markers', is however the absolute frequency stabilization of the optical comb spectrum. A powerful technique for this stabilization is self-referencing, which requires a spectrum that spans a full octave, i.e. a factor of two in frequency. In the case of mode locked lasers, overcoming the limited bandwidth has become possible only with the advent of photonic crystal fibres for supercontinuum generation. Here, we report for the first time the generation of an octave-spanning frequency comb directly from a toroidal microresonator on a silicon chip. The comb spectrum covers the wavelength range...

  20. Spanning forests on the Sierpinski gasket

    Directory of Open Access Journals (Sweden)

    Shu-Chiuan Chang

    2008-04-01

    Full Text Available We present the numbers of spanning forests on the Sierpinski gasket $SG_d(n$ at stage $n$ with dimension $d$ equal to two, three and four, and determine the asymptotic behaviors. The corresponding results on the generalized Sierpinski gasket $SG_{d,b}(n$ with $d=2$ and $b=3,4$ are obtained. We also derive the upper bounds of the asymptotic growth constants for both $SG_d$ and $SG_{2,b}$.

  1. 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.

  2. Impounding Experimental Research of Large Span Aqueduct

    Directory of Open Access Journals (Sweden)

    Huafeng Deng

    2013-04-01

    Full Text Available In this study, we have a research of the impounding experimental research of large span aqueduct. Caohe aqueduct is the mark building of the middle line of the South-to-North Water Diversion Project, of which the span is 30m. For this aqueduct, the structure is relatively complicated with great technical difficulties, what’s more there's no engineering experience or theoretical method to provide reference in domestic and abroad. It can be seen clear that whether the actual stressing state, deformation conditions and prestressed tension effect etc. meet the design requirements will directly affect the safe operation of aqueduct, so the impounding experiment of the aqueduct was carried out before formal operation. At the meanwhile, the deformation characteristics and stress characteristics of the aqueduct under various impounding conditions were analyzed in detail. The experiment results analysis shows that, the aqueduct structure is under a good elastic working condition with only 0.98mm maximum deflection deformation at mid-span, which meets the design and specification requirements. At the same time, all of the measure point’s stress is in the range of designed material, which means the structure form is safe and reliable and can meet the requirements of the later operation good.

  3. 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.

  4. Contribution of adipose tissue to health span and longevity.

    Science.gov (United States)

    Huffman, Derek M; Barzilai, Nir

    2010-01-01

    Adipose tissue accounts for approximately 20% (lean) to >50% (in extreme obesity) of body mass and is biologically active through its secretion of numerous peptides and release and storage of nutrients such as free fatty acids. Studies in rodents and humans have revealed that body fat distribution, including visceral fat (VF), subcutaneous (SC) fat and ectopic fat are critical for determining the risk posed by obesity. Specific depletion or expansion of the VF depot using genetic or surgical strategies in animal models has proven to have direct effects on metabolic characteristics and disease risk. In humans, there is compelling evidence that abdominal obesity most strongly predicts mortality risk, while in rats, surgical removal of VF improves mean and maximum life span. There is also growing evidence that fat deposition in ectopic depots such as skeletal muscle and liver can cause lipotoxicity and impair insulin action. Conversely, expansion of SC adipose tissue may confer protection from metabolic derangements by serving as a 'metabolic sink' to limit both systemic lipids and the accrual of visceral and ectopic fat. Treatments targeting the prevention of fat accrual in these harmful depots should be considered as a primary target for improving human health span and longevity. PMID:20703052

  5. Chronology of Mercury's geological and geophysical evolution - the Vulcanoid hypothesis

    International Nuclear Information System (INIS)

    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

  6. A new chronology for the Moon and Mercury

    CERN Document Server

    Marchi, S; Cremonese, G; Massironi, M; Martellato, E

    2009-01-01

    In this paper we present a new method for dating the surface of the Moon, obtained by modeling the incoming flux of impactors and converting it into a size distribution of resulting craters. We compare the results from this model with the standard chronology for the Moon showing their similarities and discrepancies. In particular, we find indications of a non-constant impactor flux in the last 500 Myr and also discuss the implications of our findings for the Late Heavy Bombardment hypothesis. We also show the potential of our model for accurate dating of other inner Solar System bodies, by applying it to Mercury.

  7. Extension of Chronological Calculus for Dynamical Systems on Manifolds

    OpenAIRE

    Kipka, Robert J.; Ledyaev, Yuri S.

    2014-01-01

    We propose an extension of the Chronological Calculus, developed by Agrachev and Gamkrelidze for the case of $C^\\infty$-smooth dynamical systems on finite-dimensional $C^\\infty$-smooth manifolds, to the case of $C^m$-smooth dynamical systems and infinite-dimensional $C^m$-manifolds. Due to a relaxation in the underlying structure of the calculus, this extension provides a powerful computational tool without recourse to the theory of calculus in Fr\\'echet spaces required by the classical Chron...

  8. Organic carbon sedimentation rates in Asian mangrove coastal ecosystems estimated by {sup 210}PB chronology

    Energy Technology Data Exchange (ETDEWEB)

    Tateda, Y.; Wattayakorn, G.; Nhan, D.D.; Kasuya, Y. [Abiko Research Laboratory CRIEPI, Biology Dept., Abiko, Chiba (Japan)

    2004-07-01

    Organic carbon balance estimation of mangrove coastal ecosystem is important for understanding of Asian coastal carbon budget/flux calculation in global carbon cycle modelling which is powerful tool for the prediction of future greenhouse gas effect and evaluation of countermeasure preference. Especially, the organic carbon accumulation rate in mangrove ecosystem was reported to be important sink of carbon as well as that in boreal peat accumulation. For the estimation of 10{sup 3} years scale organic carbon accumulation rates in mangrove coastal ecosystems, {sup 14}C was used as long term chronological tracer, being useful in pristine mangrove forest reserve area. While in case of mangrove plantation of in coastal area, the {sup 210}Pb is suitable for the estimation of decades scale estimation by its half-life. Though it has possibility of bio-/physical- turbation effect in applying {sup 210}Pb chronology that is offset in case of 10{sup 3} years scale estimation, especially in Asian mangrove ecosystem where the anthropogenic physical turbation by coastal fishery is vigorous.In this paper, we studied the organic carbon and {sup 210}Pb accumulation rates in subtropical mangrove coastal ecosystems in Japan, Vietnam and Thailand with {sup 7}Be analyses to make sure the negligible effect of above turbation effects on organic carbon accumulation. We finally concluded that {sup 210}Pb was applicable to estimate organic carbon accumulation rates in these ecosystems even though the physical-/bio-turbation is expected. The measured organic carbon accumulation rates using {sup 210}Pb in mangrove coastal ecosystems of Japan, Vietnam and Thailand were 0.067 4.0 t-C ha{sup -1} y{sup -1}. (author)

  9. Interorganizational Boundary Spanning in Global Software Development

    DEFF Research Database (Denmark)

    Søderberg, Anne-Marie; Romani, Laurence

    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...... 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 the...

  10. 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....

  11. Approaches to chronological age assessment based on dental calcification.

    Science.gov (United States)

    Bolanos, M V; Manrique, M C; Bolanos, M J; Briones, M T

    2000-05-15

    The aim of the present study was to find an accurate estimation of chronological age using a small number of selected teeth. For this purpose, the method devised by Nolla [C. Nolla, The development of the permanent teeth, J. Dent. Child. 27 (1960) 254-266.] was used: the development of each of the teeth was determined according to this method on 374 radiographs, 195 of boys (mean age 8.59) and 179 of girls (mean age 8.75). The 28 variables representing the calcification stages were analyzed using cluster analysis followed by multivariate analysis (multiple linear regression model). Patient age was considered to be a dependent variable. Our study showed that antimere teeth are the most homogeneous as regards stages of development. The prediction was more accurate for boys and girls below 10 years of age, using teeth 21, 43 and 46 from boys and teeth 21, 46 and 47 from girls. These teeth accounted for 80% total variance of chronological age for dental calcification. Standard error was +/-1.4 years for boys and +/-1.2 years for girls. When the age of the children remained completely unknown, the best estimates were provided by teeth 43, 47, 46 and 44 from boys and teeth 44, 47 and 43 from girls. PMID:10808098

  12. Early Mars: A regional assessment of denudation chronology

    Science.gov (United States)

    Maxwell, T. A.; Craddock, R. A.

    1993-01-01

    Within the oldest highland units on Mars, the record of crater degradation indicates that fluvial resurfacing was responsible for modifying the Noachian through middle-Hesperian crater population. Based on crater frequency in the Noachian cratered terrain, age/elevation relations suggest that the highest exposures of Noachian dissected and plateau units became stabilized first, followed by successively lower units. In addition, studies of drainage networks indicate that the frequency of Noachian channels is greatest at high elevations. Together, these observations provide strong evidence of atmospheric involvement in volatile recycling. The long time period of crater modification also suggests that dendritic highland drainage was not simply the result of sapping by release of juvenile water, because the varied geologic units as well as the elevation dependence of stability ages makes it unlikely that subsurface recycling could provide a continuous supply of water for channel formation by sapping. While such geomorphic constraints on volatile history have been established by crater counts and stratigraphic relations using the 1:2M photomosaic series, photogeologic age relationships at the detailed level are needed to establish a specific chronology of erosion and sedimentation. Age relations for discrete erosional slopes and depositional basins will help refine ages of fluvial degradation, assess effectiveness of aeolian processes, and provide a regional chronology of fluvial events.

  13. Chronologic changes of free fat graft in rabbit using CT

    International Nuclear Information System (INIS)

    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)

  14. Sequence of events from the onset to the demise of the Last Interglacial: Evaluating strengths and limitations of chronologies used in climatic archives

    Science.gov (United States)

    Govin, A.; Capron, E.; Tzedakis, P. C.; Verheyden, S.; Ghaleb, B.; Hillaire-Marcel, C.; St-Onge, G.; Stoner, J. S.; Bassinot, F.; Bazin, L.; Blunier, T.; Combourieu-Nebout, N.; El Ouahabi, A.; Genty, D.; Gersonde, R.; Jimenez-Amat, P.; Landais, A.; Martrat, B.; Masson-Delmotte, V.; Parrenin, F.; Seidenkrantz, M.-S.; Veres, D.; Waelbroeck, C.; Zahn, R.

    2015-12-01

    The Last Interglacial (LIG) represents an invaluable case study to investigate the response of components of the Earth system to global warming. However, the scarcity of absolute age constraints in most archives leads to extensive use of various stratigraphic alignments to different reference chronologies. This feature sets limitations to the accuracy of the stratigraphic assignment of the climatic sequence of events across the globe during the LIG. Here, we review the strengths and limitations of the methods that are commonly used to date or develop chronologies in various climatic archives for the time span (˜140-100 ka) encompassing the penultimate deglaciation, the LIG and the glacial inception. Climatic hypotheses underlying record alignment strategies and the interpretation of tracers are explicitly described. Quantitative estimates of the associated absolute and relative age uncertainties are provided. Recommendations are subsequently formulated on how best to define absolute and relative chronologies. Future climato-stratigraphic alignments should provide (1) a clear statement of climate hypotheses involved, (2) a detailed understanding of environmental parameters controlling selected tracers and (3) a careful evaluation of the synchronicity of aligned paleoclimatic records. We underscore the need to (1) systematically report quantitative estimates of relative and absolute age uncertainties, (2) assess the coherence of chronologies when comparing different records, and (3) integrate these uncertainties in paleoclimatic interpretations and comparisons with climate simulations. Finally, we provide a sequence of major climatic events with associated age uncertainties for the period 140-105 ka, which should serve as a new benchmark to disentangle mechanisms of the Earth system's response to orbital forcing and evaluate transient climate simulations.

  15. Matroidal Degree-Bounded Minimum Spanning Trees

    CERN Document Server

    Zenklusen, Rico

    2011-01-01

    We consider the minimum spanning tree (MST) problem under the restriction that for every vertex v, the edges of the tree that are adjacent to v satisfy a given family of constraints. A famous example thereof is the classical degree-constrained MST problem, where for every vertex v, a simple upper bound on the degree is imposed. Iterative rounding/relaxation algorithms became the tool of choice for degree-bounded network design problems. A cornerstone for this development was the work of Singh and Lau, who showed for the degree-bounded MST problem how to find a spanning tree violating each degree bound by at most one unit and with cost at most the cost of an optimal solution that respects the degree bounds. However, current iterative rounding approaches face several limits when dealing with more general degree constraints. In particular, when several constraints are imposed on the edges adjacent to a vertex v, as for example when a partition of the edges adjacent to v is given and only a fixed number of elemen...

  16. Social Network Changes and Life Events across the Life Span: A Meta-Analysis

    Science.gov (United States)

    Wrzus, Cornelia; Hanel, Martha; Wagner, Jenny; Neyer, Franz J.

    2013-01-01

    For researchers and practitioners interested in social relationships, the question remains as to how large social networks typically are, and how their size and composition change across adulthood. On the basis of predictions of socioemotional selectivity theory and social convoy theory, we conducted a meta-analysis on age-related social network…

  17. Variable Span Filters for Speech Enhancement

    DEFF Research Database (Denmark)

    Jensen, Jesper Rindom; Benesty, Jacob; Christensen, Mads Græsbøll

    2016-01-01

    In this work, we consider enhancement of multichannel speech recordings. Linear filtering and subspace approaches have been considered previously for solving the problem. The current linear filtering methods, although many variants exist, have limited control of noise reduction and speech...... distortion. Subspace approaches, on the other hand, can potentially yield better control by filtering in the eigen-domain, but traditionally these approaches have not been optimized explicitly for traditional noise reduction and signal distortion measures. Herein, we combine these approaches by deriving...... optimal filters using a joint diagonalization as a basis. This gives excellent control over the performance, as we can optimize for noise reduction or signal distortion performance. Results from real data experiments show that the proposed variable span filters can achieve better performance than existing...

  18. Galactic Archaeology and Minimum Spanning Trees

    CERN Document Server

    Macfarlane, B A; Flynn, C M L

    2015-01-01

    Chemical tagging of stellar debris from disrupted open clusters and associations underpins the science cases for next-generation multi-object spectroscopic surveys. As part of the Galactic Archaeology project TraCD (Tracking Cluster Debris), a preliminary attempt at reconstructing the birth clouds of now phase-mixed thin disk debris is undertaken using a parametric minimum spanning tree (MST) approach. Empirically-motivated chemical abundance pattern uncertainties (for a 10-dimensional chemistry-space) are applied to NBODY6-realised stellar associations dissolved into a background sea of field stars, all evolving in a Milky Way potential. We demonstrate that significant population reconstruction degeneracies appear when the abundance uncertainties approach 0.1 dex and the parameterised MST approach is employed; more sophisticated methodologies will be required to ameliorate these degeneracies.

  19. Stable, Renormalizable, Scalar Tachyonic Quantum Field Theory with Chronology Protection

    CERN Document Server

    Radzikowski, Marek J

    2008-01-01

    We use microlocal arguments to suggest that Lorentz symmetry breaking must occur in a reasonably behaved tachyonic quantum field theory that permits renormalizability. In view of this, we present a scalar tachyonic quantum field model with manifestly broken Lorentz symmetry and without exponentially growing/decaying modes. A notion of causality, in which anti-telephones are excluded, and which is viewed as a form of chronology protection, is obeyed. The field theory is constructed in a preferred tachyon frame in terms of commuting creation/annihilation operators. We calculate some sample (renormalized) operators in this preferred frame, argue that the Hadamard condition is satisfied, and discuss the PCT and spin-statistics theorems for this model.

  20. Construction validity in equilibrium tests: chronological order in tasks presentation

    Directory of Open Access Journals (Sweden)

    Maria Duarte Caetano

    2006-09-01

    Full Text Available The equilibrium tests of the Rosa Neto1 Motor evelopment Scale are constituted by ten tasks related to the chronological ages from 2 to 11 years and they determine the participants Motor Age. The tests presentation order is crescent from the child chronological age and the motor age is based on the success or failure in each task. The aim of this study was to analyze the construction validity of the equilibrium motor tests observing the ordering the levels of task difficulty. 76 children with 6 to 9 years of chronological age participated and were assigned in two groups: control group, tests presentation in increased order; and inverted group, tests presentation in decreased order. The results did not revealed statistical significant differences between groups, which indicatethat the presentation order of the tests did not interfere in the children performance, independently of the chronological age. Low success rates occurred in some specific tasks followed by success in advanced tasks. As the results revealed that the participants could perform the tasks after that in which the failure happened the motor age ascribed by the Motor Development Scale can underestimate the children motor development. The variation of the children performance in the tasks suggests that the motor development process is nonlinear. The equilibrium motor tasks purposed in the Motor Development Scale show construction validity. RESUMO Os testes de equilíbrio da Escala de Desenvolvimento Motor de Rosa Neto1 são constituídos por dez tarefas correspondentes às idades cronológicas de 2 a 11 anos e determinam a Idade Motora dos participantes. A ordem de apresentação dos testes é crescente, partindo da idade cronológica da criança e a idade motora baseia-se no sucesso ou fracasso em cada tarefa. O objetivo deste estudo foi analisar a validade de construção dos testes motores em equilíbrio, observando a ordenação e os graus de dificuldade da tarefa. Participaram

  1. Thermoluminescence dating. Application to the chronology of volcanic ashes

    International Nuclear Information System (INIS)

    Thermoluminescent (TL) dating is generally used for minerals heated in the past and can be used for absolute chronology of volcanic ashes but seems limited to less than 15.000 years. The aim of the thesis is the study of thermoluminescent properties of quartz for high doses and long irradiations using the red TL peak of quartz which is situated at high temperature (about 370 deg. C) to extend the method for higher ages. A theory, based on spatial correlation between electron and hole created during the same ionization, is developed. A chapter is devoted to dosimetry because of its importance in TL dating, especially alpha scintillation counting and the influence of humidity on the determination of annual dose. Volcanic samples are dated from 10.000 to 80.000 years before present

  2. Frost-ring chronologies as dendroclimatic proxies of boreal environments

    Science.gov (United States)

    Payette, Serge; Delwaide, Ann; Simard, Martin

    2010-01-01

    Frost rings are formed in tree stems when growing-season frosts affect immature wood cells, producing collapsed cells within annual tree rings. Open boreal forests are most susceptible to record growing-season frost because they lack the greenhouse effect commonly observed in closed forests. Here we present a novel method to construct regional frost-ring chronologies in lichen-black spruce woodlands of the boreal forest zone. Because the ability of trees to form frost rings depends on several factors (including bark thickness and ring width), we used two models to produce a Frost Composite Index based on a frost susceptibility window of cambial age growing-season frost activity may be used as dendroclimatic proxies of climate variability and may give insights into future risks of frost damage in a warming climate.

  3. School Attendance Patterns, Unmet Educational Needs, and Truancy: A Chronological Perspective

    Science.gov (United States)

    Spencer, Andrea M.

    2009-01-01

    This study examines chronological patterns of attendance and academic performance of urban students who are identified as truants in Grade 8. A chronological review of 42 student records, from school entry through Grade 8, identified high frequencies of absenteeism and academic performance issues beginning at school entry and, in many cases,…

  4. TELL SABI ABYAD, SYRIA : RADIOCARBON CHRONOLOGY, CULTURAL CHANGE, AND THE 8.2 KA EVENT

    NARCIS (Netherlands)

    van der Plicht, J.; Akkermans, P. M. M. G.; Nieuwenhuyse, O.; Kaneda, A.; Russell, A.

    2011-01-01

    At Tell Sabi Abyad, Syria, we obtained a robust chronology for the 7th to early 6th millennium BC, the Late Neolithic. The chronology was obtained using a large set of radiocarbon dates, analyzed by Bayesian statistics. Cultural changes observed at similar to 6200 BC are coeval with the 8.2 ka clima

  5. A sub-fossil kauri (Agathis australis) tree-ring chronology

    International Nuclear Information System (INIS)

    A 491-year floating tree-ring chronology was constructed using sub-fossil bog kauris, Agathis australis, from a site near Huntly, North Island, New Zealand. The chronology has been approximately dated to within the period 3,500 B.P. to 3,000 B.P. by radiocarbon dating. This is the first sub-fossil New Zealand chronology, and shows the potential for the formation of a long chronology from the present back over several millenia. The applications of this chronology and its possible extensions include radiocarbon calibration for the Southern Hemisphere, and climatic reconstructions based on ring-widths. It will also assist interpretation of the history of the Waikato Valley over the last few millenia

  6. Seismic performance evaluation for super-long span cable-stayed bridges

    Institute of Scientific and Technical Information of China (English)

    Ye Aijun; Wu Shouchang

    2009-01-01

    Based on the capacity/demand (C/D) analysis of bridge components, and life cycle and performance based seismic design principles, a practical approach is developed for the seismic performance evaluation of super-long span cable-stayed bridges. According to the approach, the seismic performance evaluation of the Sutong Bridge, which is a cable-stayed bridge with a main span of 1 088 m, is completed, and the practicality of the approach is validated. The earthquake resistance level for super-long span cable-stayed bridges is discussed, including the earthquake level, its corresponding structural performance and check indices. And a set of formula for capacity/demand ratio calculation of bridge components is proposed.

  7. Chronological dating and tectonic implications of late Cenozoic volcanic rocks and lacustrine sequence in Oiyug Basin of southern Tibet

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Reconstruction of uplift history of the Tibetan Plateau is crucial for understanding its environmental impacts. The Oiyug Basin in southern Tibet contains multiple periods of sedimentary sequences and volcanic rocks that span much of the Cenozoic and has great potential for further studying this issue. However, these strata were poorly dated. This paper presents a chronological study of the 145 m thick and horizontally-distributed lacustrine sequence using paleomagnetic method as well as a K-Ar dating of the underlying volcanic rocks. Based on these dating results, a chronostratigraphic framework and the basin-developmental history have been established for the past 15 Ma, during which three tectonic stages are identified. The period of 15-8.1 Ma is characterized by intense volcanic activities involving at least three major eruptions. Subsequently, the basin came into a tectonically quiescent period and a lacustrine sedimentary sequence was developed. Around 2.5 Ma, an N-S fault occurred across the southern margin of the basin, leading to the disappearance of the lake environment and the development of the Oiyug River. The Gyirong basin on northern slope of the Himalayas shows a similar basin developmental history and thus there is a good agreement in tectonic activities between the Himalayan and Gangdise orogenic belts. Therefore, the tectonic evolution stages experienced by the Oiyug Basin during the past 15 Ma could have a regional significance for southern Tibet. The chronological data obtained from this study may provide some constraints for further studies with regard to the tectonic processes and environmental changes in southern Tibetan Plateau.

  8. Spanning the Home/Work Creative Space

    DEFF Research Database (Denmark)

    Davis, Lee N.; Davis, Jerome; Hoisl, Karin

    This paper explores the link between employee leisure time activities and the value of their creative output. We argue that leisure time activities – both in general, and specifically with regard to the employee’s choice of hobbies – both illuminate and shape the attitudes and attributes the empl......This paper explores the link between employee leisure time activities and the value of their creative output. We argue that leisure time activities – both in general, and specifically with regard to the employee’s choice of hobbies – both illuminate and shape the attitudes and attributes...... 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...... – given the range of multi-level inputs that may also contribute to workplace creativity. We use original survey data comprising 4,138 inventions from 21 European countries, the United States and Japan, in all major industries. Organizational creativity is measured by the asset value of the patent...

  9. Reduced span spray: Part 3: Design of a narrow span nozzle

    OpenAIRE

    De Cock, Nicolas; Massinon, Mathieu; Ouled Taleb Salah, Sofiene; Lebeau, Frédéric

    2016-01-01

    Optimisation of the droplet spectra of the agricultural spray may increase the spray application efficiency. The optimal spray would contain only the most efficient droplets in term of speed and size. Therefore, this paper is presenting the first steps of the design of a narrow span nozzle in order to produce an optimised spray. The starting geometry is a splash plate nozzle with a disk ending with structures (i.e. tooth, grooves, and needles) that would separate the liquid sheet...

  10. Characterising the Welsh Roundhouse: chronology, inhabitation and landscape

    Directory of Open Access Journals (Sweden)

    Eleanor Ghey

    2007-11-01

    Full Text Available The article stems from a one-year project funded by the University of Wales Board of Celtic Studies to collect and analyse all the evidence for excavated prehistoric and early historic roundhouses in Wales. The resulting dataset will serve as a resource for researchers and, through the analysis provided in this article, provide an important counterpoint to similar studies from elsewhere in Britain. The methodology of the project is presented, and the limitations of the data are discussed in detail. The principal difficulties were associated with dating the building and duration of use of individual structures, and the bias created by a few sites with large numbers of excavated structures. The analysis and interpretation of the data is presented in three sections: chronology, inhabitation and landscape, and historical overview. The emphasis on recently excavated sites with good chronological control has enabled a more confident reconstruction of the history of roundhouse occupation in Wales. This has shown that while the architectural form has relatively early origins with numbers beginning to grow after 1500 BC, it is primarily a feature of first millennium BC and early first millennium AD landscapes. During the first millennium BC, timber- and stone-built settlements are common, initially as enclosed sites, and later, by the Roman period, as both open and enclosed settlements. This is contrary to the situation in many other parts of Britain, where roundhouses and frequently field systems are dated to at least the mid-second millennium BC onwards. There were strong regional differences between regions at this time, with for instance the predominance of stone- and clay-built sites in north-west Wales and the absence of Roman period roundhouses in the north-east. The dataset derived from the project will remain as an important resource with which to research these regional differences in greater detail and to examine the implications of new

  11. Holographic Protection of Chronology in Universes of the Godel Type

    Energy Technology Data Exchange (ETDEWEB)

    Boyda, Edward; Ganguli, Surya; Horava, Petr; Varadarajan, Uday

    2002-12-07

    We analyze the structure of supersymmetric Godel-like cosmological solutions of string theory. Just as the original four-dimensional Godel universe, these solutions represent rotating, topologically trivial cosmologies with a homogeneous metric and closed timelike curves. First we focus on"phenomenological" aspects of holography, and identify the preferred holographic screens associated with inertial comoving observers in Godel universes. We find that holography can serve as a chronology protection agency: The closed timelike curves are either hidden behind the holographic screen, or broken by it into causal pieces. In fact, holography in Godel universes has many features in common with de Sitter space, suggesting that Godel universes could represent a supersymmetric laboratory for addressing the conceptual puzzles of de Sitter holography. Then we initiate the investigation of"microscopic" aspects of holography of Godel universes in string theory. We show that Godel universes are T-dual to pp-waves, and use this fact to generate new Godel-like solutions of string and M-theory by T-dualizing known supersymmetric pp-wave solutions.

  12. Chronology protection in Galileon models and massive gravity

    Energy Technology Data Exchange (ETDEWEB)

    Burrage, Clare; Rham, Claudia de; Heisenberg, Lavinia [Départment de Physique Théorique and Center for Astroparticle Physics, Université de Genève, 24 Quai E. Ansermet, CH-1211 Genève (Switzerland); Tolley, Andrew J., E-mail: Clare.Burrage@nottingham.ac.uk, E-mail: claudia.deRham@case.edu, E-mail: Lavinia.heisenberg@googlemail.com, E-mail: andrew.j.tolley@case.edu [Department of Physics, Case Western Reserve University, 10900 Euclid Ave, Cleveland, OH 44106 (United States)

    2012-07-01

    Galileon models are a class of effective field theories that have recently received much attention. They arise in the decoupling limit of theories of massive gravity, and in some cases they have been treated in their own right as scalar field theories with a specific nonlinearly realized global symmetry (Galilean transformation). It is well known that in the presence of a source, these Galileon theories admit superluminal propagating solutions, implying that as quantum field theories they must admit a different notion of causality than standard local Lorentz invariant theories. We show that in these theories it is easy to construct closed timelike curves (CTCs) within the naive regime of validity of the effective field theory. However, on closer inspection we see that the CTCs could never arise since the Galileon inevitably becomes infinitely strongly coupled at the onset of the formation of a CTC. This implies an infinite amount of backreaction, first on the background for the Galileon field, signaling the break down of the effective field theory, and subsequently on the spacetime geometry, forbidding the formation of the CTC. Furthermore the background solution required to create CTCs becomes unstable with an arbitrarily fast decay time. Thus Galileon theories satisfy a direct analogue of Hawking's chronology protection conjecture.

  13. Chronologic and actinically induced aging in human facial skin

    International Nuclear Information System (INIS)

    Clinical and histologic stigmata of aging are much more prominent in habitually sun-exposed skin than in sun-protected skin, but other possible manifestations of actinically induced aging are almost unexplored. We have examined the interrelation of chronologic and actinic aging using paired preauricular (sun-exposed) and postauricular (sun-protected) skin specimens. Keratinocyte cultures derived from sun-exposed skin consistently had a shorter in vitro lifespan but increased plating efficiency compared with cultures derived from adjacent sun-protected skin of the same individual, confirming a previous study of different paired body sites. Electron microscopic histologic sections revealed focal abnormalities of keratinocyte proliferation and alignment in vitro especially in those cultures derived from sun-exposed skin and decreased intercellular contact in stratified colonies at late passage, regardless of donor site. One-micron histologic sections of the original biopsy specimens revealed no striking site-related keratinocyte alterations, but sun-exposed specimens had fewer epidermal Langerhans cells (p less than 0.001), averaging approximately 50 percent the number in sun-protected skin, a possible exaggeration of the previously reported age-associated decrease in this cell population. These data suggest that sun exposure indeed accelerates aging by several criteria and that, regardless of mechanism, environmental factors may adversely affect the appearance and function of aging skin in ways amenable to experimental quantitation

  14. Life after the Principalship

    Science.gov (United States)

    Schmidt, Laurel

    2009-01-01

    Sixty-eight percent of people who are approaching retirement age report that they intend to work full time or part time after retirement, mostly because they want to. With today's life span stretching to 80 years and beyond, turning 60 is no longer an end-stage event. Instead, it is the beginning of a new developmental phase. This article…

  15. A Validation Study of the Korean Version of SPAN

    OpenAIRE

    Seo, Ho-Jun; Chung, Sangkeun; Lim, Hyun-Kook; Chee, Ik-Seung; Lee, Kyoung-Uk; Paik, Ki-Chung; Kim, Daeho; Lee, Sang-Yeol; Ryu, Seung-Ho; Kim, Jung Bum; Kim, Tae-Suk; Kim, Won; Chae, Jeong-Ho; ,

    2011-01-01

    Purpose The SPAN, which is acronym standing for its four components: Startle, Physiological arousal, Anger, and Numbness, is a short post-traumatic stress disorder (PTSD) screening scale. This study sought to develop and validate a Korean version of the SPAN (SPAN-K). Materials and Methods Ninety-three PTSD patients (PTSD group), 73 patients with non-psychotic psychiatric disorders (psychiatric control group), and 88 healthy participants (normal control group) were recruited for this study. P...

  16. Improved construction of medium-span concrete viaducts

    OpenAIRE

    Caballero, Ángel; Turmo Coderque, José

    2011-01-01

    Concreting of span by span construction with travelling scaffolding is typically made in two phases. In the first phase, webs and bottom flange of the box girder are concreted. In the second phase, top flange is concreted. Once the cross section is self-supporting, this is to say, once the concrete of the top flange is hardened, the segment can be prestressed and the scaffolding can be shifted to the next span. This procedure takes usually two weeks per span. In order to shorten the critic...

  17. Contributions of dynamic environmental signals during life-cycle transitions to early life-history traits in lodgepole pine (Pinus contorta Dougl.)

    Science.gov (United States)

    Liu, Yang; Wang, Tongli; El-Kassaby, Yousry A.

    2016-05-01

    Environmental signals are important triggers in the life-cycle transitions and play a crucial role in the life-history evolution. Yet very little is known about the leading ecological factors contributing to the variations of life-history traits in perennial plants. This paper explores both the causes and consequences for the evolution of life-history traits (i.e., seed dormancy and size) in lodgepole pine (Pinus contorta Dougl.) across British Columbia (B.C.), Canada. We selected 83 logepole pine populations covering 22 ecosystem zones of B.C. and through their geographic coordinate, 197 climatic variables were generated accordingly for the reference (1961-1990) and future (2041-2070) periods. We found that dynamic climatic variables rather than constant geographic variables are the true environmental driving forces in seed dormancy and size variations and thus provide reliable predictors in response to global climate change. Evapotranspiration and precipitation in the plant-to-seed chronology are the most critical climate variables for seed dormancy and size variations, respectively. Hence, we predicted that levels of seed dormancy in lodgepole pine would increase across large tracts of B.C. in 2050s. Winter-chilling is able to increase the magnitude of life-history plasticity and lower the bet-hedge strategy in the seed-to-plant transition; however, winter-chilling is likely to be insufficient in the north of 49° N in 2050s, which may delay germination while unfavorable conditions during dry summers may result in adverse consequences in the survival of seedlings owing to extended germination span. These findings provide useful information to studies related to assessments of seed transfer and tree adaptation.

  18. Impact Chronology of the Moon — Results from the Lunar Reconnaissance Orbiter Camera (LROC)

    Science.gov (United States)

    Hiesinger, H.; van der Bogert, C. H.; Pasckert, J. H.; Plescia, J. B.; Robinson, M. S.

    2016-05-01

    We present absolute model ages (AMAs) based on crater size-frequency distribution (CSFD) measurements for Copernicus, Tycho, North Ray, Cone, and Autolycus craters to test and possibly improve the lunar cratering chronology.

  19. The application of carbon-isotope measurements to dendro- and xylem-chronology

    International Nuclear Information System (INIS)

    We measured 14C/13C Ratio of the Teak. The 14C excess, which reflects the execution of the tropospheric nuclear tests, is stamped in the Teak trunk. In place of the annual rings this stamp can estimate the xylem-chronologies and more accurate growth rates of tropical trees which have no annual rings. And replacing the shot-pinning method we can estimate the growing period in an annual ring formed especially in 1963-1966, when the 14C concentration in the tropospheric air changes dramatically. And we measured 14C-chronologies of the annual rings of O-Hinoki, 14C-chronologies agree well with dendrochronologies for the past 600 years. And the 14C chronologies support more determinative cross-dating of the archaeological samples. (author)

  20. Comparison of Varve and 14C Chronologies from Steel Lake, Minnesota, USA

    Energy Technology Data Exchange (ETDEWEB)

    Tian, J; Brown, T A; Hu, F S

    2004-12-29

    Annually laminated sediments (varves) offer an effective means of acquiring high-quality paleoenvironmental records. However, the strength of a varve chronology can be compromised by a number of factors, such as missing varves, ambiguous laminations, and human counting error. We assess the quality of a varve chronology for the last three millennia from Steel Lake, Minnesota, through comparisons with nine AMS {sup 14}C dates on terrestrial plant macrofossils from the same core. These comparisons revealed an overall 8.4% discrepancy, primarily because of missing/uncountable varves within two stratigraphic intervals characterized by low carbonate concentrations and obscure laminations. Application of appropriate correction factors to these two intervals results in excellent agreement between the varve and {sup 14}C chronologies. These results, together with other varve studies, demonstrate that an independent age-determination method, such as {sup 14}C dating, is usually necessary to verify, and potentially correct, varve chronologies.

  1. Deciphering Solar System Chronology with Lunar In-situ Dating: The MARE Discovery Mission

    Science.gov (United States)

    Anderson, F. S.; Draper, D.; Christensen, P. R.; Olansen, J.; Devolites, J.; Harris, W.; Whitaker, T. J.; Levine, J.

    2015-10-01

    We have proposed a discovery mission called the Moon Age and Regolith Explorer (MARE) that will land southwest of the Aristarchus Plateau, providing new measurements of age and petrology, addressing major questions of lunar and solar system chronology.

  2. Isotope chronological trace of granite gravel in Hefei Basin

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The discovery of granite gravel in Hefei Jurassic backland basin, which came from the Dabie Shah or North Huaiyang, has a great significance for probing into uplift and exhumation of the Dabie orogenic belt. Lithochemical and isotope chronological analyses on the granite gravel in the Sanjianpu Formation and the Fenghuangtai Formation in Jinzhai County prove that post-orogenic granite was developed in the major provenance of the Hefei Basin; that is, Dabie Shah or North Huaiyang. Discordant lower intersection point age of zircon U-Pb of granite gravel is 40Ar/39about 214 Ma, and Ar/39Ar age of muscovite about 196 Ma,K-Ar age of K-spar about 181 Ma. The former is the diagenetic age of the sample, and the latter two represent the sealed ages of muscovite and K-spar respectively. The age of sedimentary rocks in which a lot of granite gravels appear in the sedimentary section may represent the newest age of the exhumation of the granite body, so we assume that the age is 166 Ma. Therefore, we calculated the uplift rates of the granite body from Late Triassic to early Middle Jurassic; that is about 0.08 km/Ma and 0.4-0.3 km/Ma in the early slowly uplifting stage and later fast uplifting stage respectively, after the formation of the body at 214 Ma. These results are basically identical to the uplifting ages of the Dabie ultrahigh pressure metamorphic (UHPM) belt and the North Huaiyang thrust belt.

  3. Chronology of Awareness About US National Park External Threats

    Science.gov (United States)

    Shafer, Craig L.

    2012-12-01

    The objective of this paper is to raise understanding of the history of protected area external threat awareness in the United States and at World Protected Area Congresses. The earliest concerns about external threats to US national parks began in the late nineteenth century: a potential railroad transgression of Yellowstone National Park in the 1880s. During the early and mid 1930s, George Wright and colleagues focused on outside boundary concerns like of hunting and trapping of furbearers, grazing, logging, disease and hybridization between species. In the 1960s, a worldwide recognition began about the role of outside habitat fragmentation/isolation on nature reserves and human generated stressors crossing their boundaries. The State of the Park Report 1980 added a plethora of threats: oil/gas and geothermal exploration and development, hydropower and reclamation projects, urban encroachment, roads, resorts, and recreational facilities. The early 1980s ushered in political interference with NPS threats abatement efforts as well as Congressional legislative initiatives to support the abatement challenges of the agency. By 1987, the Government Accounting Office issued its first report on National Park Service (NPS) progress in dealing with external threats. Climate change impacts on parks, especially in terms of animals adjusting their temperature and moisture requirements by latitude and altitude, surfaced in the technical literature by the mid-1980s. By 1992, the world parks community stressed the need to integrate protected areas into the surrounding landscape and human community. The importance of the matrix has gradually gained appreciation in the scientific community. This chronology represents one example of national park and protected areas' institutional history contributing to the breath of modern conservation science.

  4. Luminescence Chronology Studies of a SAFOD Phase III Core Sample

    Science.gov (United States)

    Spencer, J. Q.; Hadizadeh, J.; Gratier, J.; Doan, M.

    2013-12-01

    This study is investigating the use of thermoluminescence (TL) and optically stimulated luminescence (OSL) phenomena to directly date the formation of discreet deformation microstructures present in core samples of fault gouge retrieved from the San Andreas Fault Observatory at Depth (SAFOD). Presently temporal information can only be provided by relative association via cross-cutting relationships. Absolute chronology of gouge fabric development will enable differentiation of microstructural components or domains that have developed at different deformation rates. Such data will lead to a better understanding of the fault processes of the San Andreas, and methods developed will be readily applicable to other active earthquake zones. Earlier luminescence studies were conducted on polymineral and K-feldspar from a small cube-shaped (~2.3x1.9x1.6 cm) fault gouge sample of San Andreas Fault Observatory at Depth (SAFOD) core from E11 (Hole E, Run 1, Section 2). These initial studies indicate (i) the thermal and radiation history of the mineral lattice can be assessed with TL, (ii) trap resetting is evident in both TL and infrared stimulated luminescence (IRSL) data, (iii) a small charge-trapping window between drill hole ambient temperature of ~112°C and higher energy lattice excitation via rupture events is evident in TL data from ~300-400°C, (iv) IRSL data have low natural intensity but good luminescence characteristics, and (v) single-aliquot regenerative-dose (SAR) IRSL equivalent dose (De) data have high over-dispersion but demonstrate ages ranging from decades to centuries may be measured. In addition to aspects of the above findings, this work will present further investigation of the relationship between TL and IRSL data, and effect of pulsed-irradiation in SAR protocols to mimic natural radiation dose at ambient temperature conditions at SAFOD core depth.

  5. The relationship between dental age, bone age and chronological age in underweight children

    OpenAIRE

    Vinod Kumar; Karthik Venkataraghavan; Ramesh Krishnan; Kavitha Patil; Karishma Munoli; Sandhya Karthik

    2013-01-01

    Background and Objective: The knowledge of bone age and dental age is of great importance for pediatrician and pediatric dentist. It is essential for a pediatric dentist to formulate treatment plan and it is a source of complementary information for pediatrician. There are few studies, which showed the relationship between dental age, bone age and chronological age in underweight children. Therefore, objective of this study was to determine and compare dental age, bone age and chronological a...

  6. The early Neolithic Volling site of Kildevang : its chronology and intra-spacial organisation

    OpenAIRE

    Ravn, Mads

    2011-01-01

    Due to the lack of large undisturbed sites, questions relating to the early Neolithic I (ENI) transition in Scandinavia, 6,000 years ago, reapeatedly get caught up in discussions of chronology and the nature of the fragmentary and regionalized source material. This paper presents an uncontaminated ENI Volling site in Eastern Jutland, Denmark, dating to around 3800 cal BC. It outlines a high-resolution ceramics chronology by combining stylistic elements with combinations of other finds. With 3...

  7. Impact of tumor chronology and tumor biology on lymph node metastasis in breast cancer

    OpenAIRE

    Smeets, Ann; Ryckx, Andries; Belmans, Ann; Wildiers, Hans; Neven, Patrick; Floris, Giuseppe; Schöffski, Patrick; Christiaens, Marie-Rose

    2013-01-01

    Synopsis The significance of nodal metastasis in breast cancer is under discussion. We investigated the impact of variables of tumor chronology and tumor biology on the presence of lymph node metastases. Purpose Lymph node involvement is the main prognostic factor in breast cancer. However, it is under discussion whether nodal metastasis in breast cancer only reflects the chronological age of the tumor or whether it is also a marker of tumor biology. The goal of our study was to investigate t...

  8. Evidence for last interglacial chronology and environmental change from Southern Europe

    OpenAIRE

    Achim Brauer; Allen, J.R.M.; Jens Mingram; Peter Dulski; Sabine Wulf; Huntley, B.

    2007-01-01

    Establishing phase relationships between earth-system components during periods of rapid global change is vital to understanding the underlying processes. It requires records of each component with independent and accurate chronologies. Until now, no continental record extending from the present to the penultimate glacial had such a chronology to our knowledge. Here, we present such a record from the annually laminated sediments of Lago Grande di Monticchio, southern Italy. Using this record ...

  9. Application of Bomb Radiocarbon Chronologies to Shortfin Mako (Isurus oxyrinchus)

    Energy Technology Data Exchange (ETDEWEB)

    Ardizzone, D; Cailliet, G M; Natanson, L J; Andrews, A H; Kerr, L A; Brown, T A

    2007-07-16

    and the number of samples for MIA analysis was insufficient for some months. Hence, unequivocal validation of shortfin mako age estimates has yet to be accomplished. Atmospheric testing of thermonuclear devices in the 1950s and 1960s effectively doubled the natural atmospheric radiocarbon ({sup 14}C). The elevated {sup 14}C levels were first recorded in 1957-58, with a peak around 1963. As a consequence, {sup 14}C entered the ocean through gas exchange with the atmosphere at the ocean surface and in terrestrial runoff. Despite variable oceanographic conditions, a worldwide rise of the bomb {sup 14}C signal entered the ocean mixed layer as dissolved inorganic carbon (DIC) in 1957-58. The large amounts of {sup 14}C released from the bomb tests produced a signature that can be followed through time, throughout the marine food web, and into deeper waters. The marked increase of radiocarbon levels was first measured in the DIC of seawater and in biogenic marine carbonates of hermatypic corals in Florida. Subsequently, this record was documented in corals from other regions and in the thallus of rhodoliths. The accumulation of radiocarbon in the hard parts of most marine organisms in the mixed layer (such as fish otoliths and bivalves) was synchronous with the coral time-series. This technique has been used to validate age estimates and longevity of numerous bony fishes to date, as well as to establish bomb radiocarbon chronologies from different oceans. In the first application of this technique to lamnoid sharks, validated annual band-pair deposition in vertebral growth bands for the porbeagle (Lamna nasus) aged up to 26 years. Radiocarbon values from samples obtained from 15 porbeagle caught in the western North Atlantic Ocean (some of which were known-age) produced a chronology similar in magnitude to the reference carbonate chronology for that region. The observed phase shift of about 3 years was attributed to different sources of carbon between vertebrae and those for

  10. [Chinese pine tree ring width chronology and its relations to climatic conditions in Qianshan Mountains].

    Science.gov (United States)

    Chen, Zhen-Ju; Sun, Yu; He, Xing-Yuan; Chen, Wei; Shao, Xue-Mei; Zhang, Hua-Yu; Wang, Zhong-Yu; Liu, Xiao-Yu

    2007-10-01

    Taking Chinese pine in Qianshan Mountains as a sample, the tree ring width chronology including standard, residual, and Arstan chronologies was established. The results showed that the tree ring width of Chinese pine had a higher correlation with the temperature in May - July and in September - November, and significant positive correlations were observed between the tree ring width and the extreme minimum temperature in July and mean minimum temperature in September. The chronology had significant or very significant correlations with the extreme minimum temperature in December and next January, mean minimum temperature in January, annual precipitation, and the precipitation in April, May and last December. Chinese pine had stronger responses to the monthly/yearly water vapor pressure and relative humidity. The yearly and most monthly evaporation had negative effects on the growth, being most significant for the evaporation in April - July. The narrowed tree rings recorded by the chronology demonstrated the 30 times of extreme drought since 1 800. The growth of Chinese pine in Qianshan Mountains was also affected by the climate changes on global and hemisphere scales. There existed 11-, 23- and 50- year- common periodicity between the chronology and solar activity, and 10-, 20- and 45- year- common periodicity between the chronology and geomagnetic activity. PMID:18163297

  11. Chinese pine tree ring width chronology and its relation to climate conditions in the Qianshan Mountains

    Institute of Scientific and Technical Information of China (English)

    Zhenju CHEN; Yu SUN; Xingyuan HE; Wei CHEN; Xuemei SHAO; Huayu ZHANG; Zhongyu WANG; Xiaoyu LIU

    2008-01-01

    Taking Chinese pine in Qianshan Mountains as a sample, the tree ring width chronology including Standard, Residual, and Arstan chronologies was estab-lished. The results show that the tree ring width of Chinese pine is highly correlated with the temperatures from May to July and from September to November. Statistically significant positive correlations were observed between tree ring width and the extreme minimum temperatures in July and mean minimum temperatures in September. The chronology was significantly or very significantly correlated with extreme minimum temperatures in December and the following January, with mean min-imum temperatures in January, with annual precipita-tion and with precipitation in April, May and the following December. The Chinese pine responded strongly to the monthly/yearly water vapor pressure and relative humidity. Annual and largely monthly evaporation in April-July had a negative effect on tree growth, and was particularly striking for evaporation in April-July. The narrow tree rings recorded by the chro-nology demonstrated the 30 occasions of extreme drought since 1800. The growth of ChineSe pine in the Qianshan mountains were also affected by climate changes on a hemispheric and global scale. There were 11-, 23-and 50-year-common periodicities between the chronology and solar activity and 10-, 20- and 45-year-common periodicit-ies between the chronology and geomagnetic activity.

  12. Development of the perceptual span in reading: A longitudinal study.

    Science.gov (United States)

    Sperlich, Anja; Meixner, Johannes; Laubrock, Jochen

    2016-06-01

    The perceptual span is a standard measure of parafoveal processing, which is considered highly important for efficient reading. Is the perceptual span a stable indicator of reading performance? What drives its development? Do initially slower and faster readers converge or diverge over development? Here we present the first longitudinal data on the development of the perceptual span in elementary school children. Using the moving window technique, eye movements of 127 German children in three age groups (Grades 1, 2, and 3 in Year 1) were recorded at two time points (T1 and T2) 1year apart. Introducing a new measure of the perceptual span, nonlinear mixed-effects modeling was used to separate window size effects from asymptotic reading performance. Cross-sectional differences were well replicated longitudinally. Asymptotic reading rate increased monotonously with grade, but in a decelerating fashion. A significant change in the perceptual span was observed only between Grades 2 and 3. Together with results from a cross-lagged panel model, this suggests that the perceptual span increases as a consequence of relatively well-established word reading. Stabilities of observed and predicted reading rates were high after Grade 1, whereas the perceptual span was only moderately stable for all grades. Comparing faster and slower readers as assessed at T1, in general, a pattern of stable between-group differences emerged rather than a compensatory pattern; second and third graders even showed a Matthew effect in reading rate and the perceptual span, respectively. PMID:26950508

  13. Community Engagement and Boundary-Spanning Roles at Research Universities

    Science.gov (United States)

    Weerts, David J.; Sandmann, Lorilee R.

    2010-01-01

    Over the past decade, community engagement has emerged as an important priority among many colleges and universities. This study employs a multi-case study design to examine boundary spanning practices of research universities that have adopted a community engagement agenda. A model is advanced to conceptualize spanning behaviors and to inform…

  14. ESR/U-series chronology of the Lower Palaeolithic palaeo-anthropological site of Visogliano, Trieste, Italy

    International Nuclear Information System (INIS)

    The Visogliano shelter, in north-eastern Italy, is an important Middle Pleistocene occupation site where human remains were found together with an archaic lithic industry, including choppers, chopping tools and a few proto-bifaces. It is of utmost importance to try to document this period, when a second wave of settlement colonised Western Europe, carrying new flaking techniques and tools. Combined ESR/U-series analyses, integrated with bio-stratigraphical and environmental data, define a chronological frame for the layers from which the artefacts were unearthed. The lower levels, including human remains, can be dated to the 350-500 kyr time span, in agreement with micro-mammal and stratigraphical studies. These data make Visogliano one of the oldest palaeo-anthropological sites in Italy, where human remains are directly associated with proto-bifaces, choppers and chopping tools. In Western Europe, Visogliano is contemporaneous to the G soil of the Arago Cave, France, with which it shares several similarities in faunal assemblages and radiometric data, and which contains human remains also. These data make Visogliano as one of the oldest sites in Europe where the Acheulian culture is observed. (authors)

  15. ESR/U-series chronology of the Lower Palaeolithic palaeo-anthropological site of Visogliano, Trieste, Italy

    Energy Technology Data Exchange (ETDEWEB)

    Falgueres, C.; Bahain, J.J.; Yokoyama, Y. [CNRS, UMR 5198, Museum Natl Hist Nat, Dept Prehist, F-75013 Paris, (France); Tozzi, C.; Boschian, G. [Univ Pisa, Dipartimento Sci Archeol, I-56100 Pisa, (Italy); Dolo, J.M. [CEA Saclay, Lab Natl Henri Becquerel, F-91191 Gif Sur Yvette, (France); Mercier, N.; Valladas, H. [CEA, CNRS, Lab Sci Climat and Environm, F-91198 Gif Sur Yvette, (France)

    2008-07-01

    The Visogliano shelter, in north-eastern Italy, is an important Middle Pleistocene occupation site where human remains were found together with an archaic lithic industry, including choppers, chopping tools and a few proto-bifaces. It is of utmost importance to try to document this period, when a second wave of settlement colonised Western Europe, carrying new flaking techniques and tools. Combined ESR/U-series analyses, integrated with bio-stratigraphical and environmental data, define a chronological frame for the layers from which the artefacts were unearthed. The lower levels, including human remains, can be dated to the 350-500 kyr time span, in agreement with micro-mammal and stratigraphical studies. These data make Visogliano one of the oldest palaeo-anthropological sites in Italy, where human remains are directly associated with proto-bifaces, choppers and chopping tools. In Western Europe, Visogliano is contemporaneous to the G soil of the Arago Cave, France, with which it shares several similarities in faunal assemblages and radiometric data, and which contains human remains also. These data make Visogliano as one of the oldest sites in Europe where the Acheulian culture is observed. (authors)

  16. Fuzzy α-minimum spanning tree problem: definition and solutions

    Science.gov (United States)

    Zhou, Jian; Chen, Lu; Wang, Ke; Yang, Fan

    2016-04-01

    In this paper, the minimum spanning tree problem is investigated on the graph with fuzzy edge weights. The notion of fuzzy ? -minimum spanning tree is presented based on the credibility measure, and then the solutions of the fuzzy ? -minimum spanning tree problem are discussed under different assumptions. First, we respectively, assume that all the edge weights are triangular fuzzy numbers and trapezoidal fuzzy numbers and prove that the fuzzy ? -minimum spanning tree problem can be transformed to a classical problem on a crisp graph in these two cases, which can be solved by classical algorithms such as the Kruskal algorithm and the Prim algorithm in polynomial time. Subsequently, as for the case that the edge weights are general fuzzy numbers, a fuzzy simulation-based genetic algorithm using Prüfer number representation is designed for solving the fuzzy ? -minimum spanning tree problem. Some numerical examples are also provided for illustrating the effectiveness of the proposed solutions.

  17. MULTIGENERATIONLIFE-SPAN TESTS OF THE NUTRITIONAL ADEQUACY OF SEVERAL DIETS AND CULTURE WATERS FOR CERIODAPHNIA DUBIA

    Science.gov (United States)

    The effects of four diets [Chlamydomonas reinhardtii, Selenastrum capricornutum, yeast-trout chow-Cerophyl (YTC) and YTC plus S. capricornutum] and two reconstituted waters on the vitality and fecundity of five to six life-span generations of Ceriodaphnia dubia were determined. T...

  18. A two year randomized controlled trial of human caloric restriction: feasibility and effects on predictors of health span and longevity

    Science.gov (United States)

    Background: Caloric restriction (CR), energy intake reduced below ad libitum (AL) intake, increases life span in many species. The implications for humans can be clarified by randomized controlled trials of CR. Methods: To determine CRs feasibility, safety, and effects on predictors of longevity, di...

  19. Triatoma sordida: considerações sobre o tempo de vida das formas adultas e sobre a oviposição das fêmeas Triatoma sordida: comments on the life span of the adult forms and oviposition of females

    Directory of Open Access Journals (Sweden)

    José Maria Pacheco de Souza

    1978-09-01

    Full Text Available Foram observados 53 exemplares do T. sordida que chegaram à fase alada, oriundos de 110 ovos; os machos eram em número de 22 e as fêmeas 31. Os tempos médios de duração da fase de ninfa não foram estatisticamente diferentes entre os sexos, sendo 174,6 e 170,6 dias respectivamente para machos e fêmeas. O tempo médio de vida na fase alada foi significativamente maior para as fêmeas, com 503 dias para estas e 284 para os machos. O período de oviposição correspondeu a 86,42% do tempo de fase alada das fêmeas, com a postura tendo maior intensidade na primeira metade desta fase. Cada fêmea pôs em média 570,8 ovos, variando a postura de 0,68 a 1,97 ovos por dia.Fifty three specimen of T. sordida which arrived at the adult stage were studied; there were 22 males and 31 females, all obtained from 110 eggs. The average time duration of life in the nymph phase was not statistically different between sexes, being 174.6 and 170.6 days respectively for mate and female. The females had a larger mean time duration of life as adults (503 days than the males (284 days. During their adult life, 86.42% of the time corresponded to oviposition, the greater intensity of egg-laying ocurring during the first half of the period. The mean number of eggs was 570.8 and the ratio egg/day varied from 0.68 to 1.97.

  20. A new luminescence dating chronology for the Rhafas cave site (NE Morocco): Insights into Palaeolithic human cultural change under varying palaeoenvironmental conditions in the Maghreb

    Science.gov (United States)

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

    2016-04-01

    Archaeological sites in northern Africa provide a rich record that is of increasing importance for current debates relating to the origins of modern human behaviour and to Out of Africa human dispersal events. Particular interest is placed on the cultural transition between the North African Middle Stone Age (MSA) and Late Stone Age (LSA), and the need for accurately defined chronologies, however the timing and nature of Palaeolithic human behaviour and dispersal across north-western Africa (the Maghreb) and potential correlation with environmental conditions remain poorly understood. The inland cave site of Rhafas (Morocco) preserves a long stratified sequence providing valuable chronological information about cultural changes in the Maghreb spanning the North African MSA through to the Neolithic. 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 section on the terrace in front of the cave entrance. Single grain OSL dating reliably constrains the timing of technocomplexes beyond the limits of radiocarbon by directly dating sediment associated with archaeological traces. We combine OSL dating with multi-proxy geological investigations (XRF, grain size analyses, stable isotopes, thin sections) to investigate site formation processes and reconstruct palaeoenvironmental conditions during human occupation phases at Rhafas. Our results indicate that the occupation of the site started at least in MIS 6 during a phase of relatively arid environmental conditions. Climatic amelioration after c.140 ka is associated with a change in sediment geochemistry at the site, most likely linked to a change in sediment source due to shifting wind directions. Tanged pieces - typical for the classical Aterian technocomplex - start to occur in the archaeological sequence in MIS 5, consistent with previously published chronological data from the Maghreb. From 55 ka, climatic conditions were

  1. Chronology of metal pollution offshore Coruh Mouth, Eastern Black Sea

    International Nuclear Information System (INIS)

    mouth clearly confirms the river as the source of input of heavy metals. The vertical distributions of copper concentrations are characterized by ample fluctuations (the profile at one of the sampled sites is illustrated). 137Cs was used to derive down-core chronology and, until further insight will be obtained on post-depositional processes, the observed variations in the Cu profile were tentatively attributed to variations in the input resulting from copper industry upstream Coruh. The most likely source lies in the Artvin area, where a major Cu processing center, Murgul-Artvin, is located, about 60 km from the mouth of the river. The most likely source for the increased Ba concentrations is the Cerattepe high-grade gold ore deposit near Artvin, where gold is located in oxidized barite rich units and the mining and processing of the ore results in a great quantity of Ba rich wastes. No detailed production data are at this stage available for these industries, however global data were available for Cu mining in Turkey since the early 1960s. The timeline corresponding to the measured Cu profile in Fig. 1, when taking into account transport, deposition and post-depositional processes, matches fairly well key time points such as: significant growth of the mining industry in the mid 1930s; actions to address environmental concerns starting to be implemented in the 1970s and being consolidated with the Turkish Environmental Law coming into force in 1973. Further detailed studies and additional information will be required to make a complete assessment of the site's contamination, to trace the burying of the sub-surface Cu peak, to corroborate chronologies using additional tracers and to identify effects of post-depositional processes. Combined with previous results obtained by the authors on the buffering capacity of this river's watershed, this study could improve the predictive capabilities concerning the fate of contaminants released in or deposited on the basin

  2. Chronology of metal pollution offshore Coruh mouth, eastern Black Sea

    International Nuclear Information System (INIS)

    mouth clearly confirms the river as the source of input of heavy metals. The vertical distributions of copper concentrations are characterized by ample fluctuations. 137Cs was used to derive down-core chronology and, until further insight will be obtained on post-depositional processes, the observed variations in the Cu profile were tentatively attributed to variations in the input resulting from copper industry upstream Coruh. The most likely source lies in the Artvin area, where a major Cu processing center, Murgul- Artvin, is located, about 60 km from the mouth of the river. The most likely source for the increased Ba concentrations is the Cerattepe high-grade gold ore deposit near Artvin, where gold is located in oxidized barite rich units and the mining and processing of the ore results in a great quantity of Ba rich wastes. No detailed production data are at this stage available for these industries, however global data were available for Cu mining in Turkey since the early 1960s. The timeline corresponding to the measured Cu profile, when taking into account transport, deposition and post-depositional processes, matches fairly well key time points such as: significant growth of mining industry in the mid 1930s; actions to address environmental concerns starting to be implemented in the 1970s and being consolidated with the Turkish Environmental Law coming into force in 1973. Further detailed studies and additional information will be required to make a complete assessment of the site's contamination, to trace the burying of the sub-surface Cu peak, to corroborate chronologies using additional tracers and to identify effects of post-depositional processes. Combined with previous results obtained by the authors on the buffering capacity of this river's watershed, this study could improve the predictive capabilities concerning the fate of contaminants released in or deposited on the basin

  3. The maximum weight spanning star forest problem on cactus graphs

    OpenAIRE

    Nguyen, Viet Hung

    2015-01-01

    International audience A star is a graph in which some node is incident with every edge of the graph, i.e., a graph of diameter at most 2. A star forest is a graph in which each connected component is a star. Given a connected graph G in which the edges may be weighted positively. A spanning star forest of G is a subgraph of G which is a star forest spanning the nodes of G. The size of a spanning star forest F of G is defined to be the number of edges of F if G is unweighted and the total ...

  4. Research development of digital maintenance and management system for long-span cable-stayed bridges

    Institute of Scientific and Technical Information of China (English)

    REN Yuan; HUANG Qiao; SUN Yong-ming

    2009-01-01

    Digital cable-stayed bridge maintenance and management system (DCBMS) was developed for the need of maintenance and management of long-span cable-stayed bridges. In this paper, the major functions and theoretical application of eight modules were systematically stated with the background of Harbin Songhua River cable-stayed bridge, which include data management module, inspection and measurement module, assessment module, finite element analysis module, disease diagnosis and prediction module, maintenance module, query module and help module. By analyzing and calculating the data from manual inspection database, basic database and health monitoring subsystem, DCBMS can accomplish the functions like life prediction, disease diagnosis, comprehensive assessment, maintenance and management of bridges. Therefore, the maintenance and management of long-span cable-stayed bridges can be made digital, professional and scientific. By running this system, a real-time and specific technical guidance can be provided for the maintainers and managers of longspan cable-stayed bridges.

  5. TimeSpan: Using Visualization to Explore Temporal Multi-dimensional Data of Stroke Patients.

    Science.gov (United States)

    Loorak, Mona Hosseinkhani; Perin, Charles; Kamal, Noreen; Hill, Michael; Carpendale, Sheelagh

    2016-01-01

    We present TimeSpan, an exploratory visualization tool designed to gain a better understanding of the temporal aspects of the stroke treatment process. Working with stroke experts, we seek to provide a tool to help improve outcomes for stroke victims. Time is of critical importance in the treatment of acute ischemic stroke patients. Every minute that the artery stays blocked, an estimated 1.9 million neurons and 12 km of myelinated axons are destroyed. Consequently, there is a critical need for efficiency of stroke treatment processes. Optimizing time to treatment requires a deep understanding of interval times. Stroke health care professionals must analyze the impact of procedures, events, and patient attributes on time-ultimately, to save lives and improve quality of life after stroke. First, we interviewed eight domain experts, and closely collaborated with two of them to inform the design of TimeSpan. We classify the analytical tasks which a visualization tool should support and extract design goals from the interviews and field observations. Based on these tasks and the understanding gained from the collaboration, we designed TimeSpan, a web-based tool for exploring multi-dimensional and temporal stroke data. We describe how TimeSpan incorporates factors from stacked bar graphs, line charts, histograms, and a matrix visualization to create an interactive hybrid view of temporal data. From feedback collected from domain experts in a focus group session, we reflect on the lessons we learned from abstracting the tasks and iteratively designing TimeSpan. PMID:26390482

  6. Power, Governance and Boundary Spanning Leadership in Public Sector Organisations

    DEFF Research Database (Denmark)

    Elmholdt, Claus Westergård; Fogsgaard, Morten

    2015-01-01

    public sector organizations. This research project has, among other things, highlighted the ways in which boundary spanning leadership can be related to establishing a shared pool of actions, knowledge, communication, trust and identity in the organization. Furthermore, the research project stresses the...... fact that analysis of boundary spanning leadership and power relations is an essential, significant, and critical tool in questioning different forms of management in public sector organizations. The aim of the workshop is to investigate, elucidate and discuss management across organizational units....... The general interest in this workshop, and the study of boundary spanning leadership and power in public organizations, is related to perspectives concerning the extent to which the quality of boundary spanning activities has significant spillover effects on the organization's productivity, job...

  7. Maintenance of cellular ATP level by caloric restriction correlates chronological survival of budding yeast

    International Nuclear Information System (INIS)

    Highlights: •CR decreases total ROS and mitochondrial superoxide during the chronological aging. •CR does not affect the levels of oxidative damage on protein and DNA. •CR contributes extension of chronological lifespan by maintenance of ATP level -- Abstract: The free radical theory of aging emphasizes cumulative oxidative damage in the genome and intracellular proteins due to reactive oxygen species (ROS), which is a major cause for aging. Caloric restriction (CR) has been known as a representative treatment that prevents aging; however, its mechanism of action remains elusive. Here, we show that CR extends the chronological lifespan (CLS) of budding yeast by maintaining cellular energy levels. CR reduced the generation of total ROS and mitochondrial superoxide; however, CR did not reduce the oxidative damage in proteins and DNA. Subsequently, calorie-restricted yeast had higher mitochondrial membrane potential (MMP), and it sustained consistent ATP levels during the process of chronological aging. Our results suggest that CR extends the survival of the chronologically aged cells by improving the efficiency of energy metabolism for the maintenance of the ATP level rather than reducing the global oxidative damage of proteins and DNA

  8. Maintenance of cellular ATP level by caloric restriction correlates chronological survival of budding yeast

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Joon-Seok; Lee, Cheol-Koo, E-mail: cklee2005@korea.ac.kr

    2013-09-13

    Highlights: •CR decreases total ROS and mitochondrial superoxide during the chronological aging. •CR does not affect the levels of oxidative damage on protein and DNA. •CR contributes extension of chronological lifespan by maintenance of ATP level -- Abstract: The free radical theory of aging emphasizes cumulative oxidative damage in the genome and intracellular proteins due to reactive oxygen species (ROS), which is a major cause for aging. Caloric restriction (CR) has been known as a representative treatment that prevents aging; however, its mechanism of action remains elusive. Here, we show that CR extends the chronological lifespan (CLS) of budding yeast by maintaining cellular energy levels. CR reduced the generation of total ROS and mitochondrial superoxide; however, CR did not reduce the oxidative damage in proteins and DNA. Subsequently, calorie-restricted yeast had higher mitochondrial membrane potential (MMP), and it sustained consistent ATP levels during the process of chronological aging. Our results suggest that CR extends the survival of the chronologically aged cells by improving the efficiency of energy metabolism for the maintenance of the ATP level rather than reducing the global oxidative damage of proteins and DNA.

  9. Exploring boundary-spanning practices among creativity managers

    DEFF Research Database (Denmark)

    Andersen, Poul Houman; Kragh, Hanne

    2015-01-01

    Purpose – External inputs are critical for organisational creativity. In order to bridge different thought worlds and cross-organisational barriers, managers must initiate and motivate boundary spanning processes. The purpose of this paper is to explore how boundary spanners manage creativity pro...... self-reflection. Originality/value – The authors contribute to research on boundary spanning practices by linking to creativity research, and bridge to research on management and governance in distributed and lessdefined organisations....

  10. A Minimum Spanning Tree Representation of Anime Similarities

    OpenAIRE

    Wibowo, Canggih Puspo

    2016-01-01

    In this work, a new way to represent Japanese animation (anime) is presented. We applied a minimum spanning tree to show the relation between anime. The distance between anime is calculated through three similarity measurements, namely crew, score histogram, and topic similarities. Finally the centralities are also computed to reveal the most significance anime. The result shows that the minimum spanning tree can be used to determine the similarity anime. Furthermore, by using centralities ca...

  11. Spanning connectedness and Hamiltonian thickness of graphs and interval graphs

    OpenAIRE

    Li, Peng; Wu, Yaokun

    2015-01-01

    International audience A spanning connectedness property is one which involves the robust existence of a spanning subgraph which is of some special form, say a Hamiltonian cycle in which a sequence of vertices appear in an arbitrarily given ordering, or a Hamiltonian path in the subgraph obtained by deleting any three vertices, or three internally-vertex-disjoint paths with any given endpoints such that the three paths meet every vertex of the graph and cover the edges of an almost arbitra...

  12. Completely Independent Spanning Trees in (Partial k-Trees

    Directory of Open Access Journals (Sweden)

    Matsushita Masayoshi

    2015-08-01

    Full Text Available Two spanning trees T1 and T2 of a graph G are completely independent if, for any two vertices u and v, the paths from u to v in T1 and T2 are internally disjoint. For a graph G, we denote the maximum number of pairwise completely independent spanning trees by cist(G. In this paper, we consider cist(G when G is a partial k-tree.

  13. SOLVING MINIMUM SPANNING TREE PROBLEM WITH DNA COMPUTING

    Institute of Scientific and Technical Information of China (English)

    Liu Xikui; Li Yan; Xu Jin

    2005-01-01

    Molecular programming is applied to minimum spanning problem whose solution requires encoding of real values in DNA strands. A new encoding scheme is proposed for real values that is biologically plausible and has a fixed code length. According to the characteristics of the problem, a DNA algorithm solving the minimum spanning tree problem is given. The effectiveness of the proposed method is verified by simulation. The advantages and disadvantages of this algorithm are discussed.

  14. Progress in the Early Solar System Chronology: A Sketch of an Ever-Changing Landscape

    Science.gov (United States)

    Amelin, Yuri; Yin, Q.-Z.; Krot, A. N.; Bouvier, A.; Wadhwa, M.; Kleine, T.; Nyquist, L. E.

    2011-01-01

    The years since the Workshop on the Chronology of Meteorites and the Early Solar System, are marked with ongoing progress in cosmochronology. Rapid improvements in techniques, discovery of new meteorites unlike any previously known, and findings that what was deemed well established constants are actually variables, will be reflected in an updated review of the solar system chronology we are currently preparing. Along with updating the database of meteorite ages, it will involve development of a set of criteria for evaluation of accuracy and consistency of isotopic dates across the entire range of meteorite classes and isotope chronometer systems. Here we present some ideas on what we think is important in meteorite chronology, and invite the cosmochemistry community to discuss them.

  15. Thirty years together: A chronology of U.S.-Soviet space cooperation

    Science.gov (United States)

    Portree, David S. F.

    1993-01-01

    The chronology covers 30 years of cooperation between the U.S. and the Soviet Union (and its successor, the Commonwealth of Independent States, of which the Russian Federation is the leading space power). It tracks successful cooperative projects and failed attempts at space cooperation. Included are the Dryden-Blagonravov talks; the UN Space Treaties; the Apollo Soyuz Test Project; COSPAS-SARSAT; the abortive Shuttle-Salyut discussions; widespread calls for joint manned and unmanned exploration of Mars; conjectural plans to use Energia and other Russian space hardware in ambitious future joint missions; and contemporary plans involving the U.S. Shuttle, Russian Mir, and Soyuz-TM. The chronology also includes events not directly related to space cooperation to provide context. A bibliography lists works and individuals consulted in compiling the chronology, plus works not used but relevant to the topic of space cooperation.

  16. The Role of Covert Retrieval in Working Memory Span Tasks: Evidence from Delayed Recall Tests

    OpenAIRE

    McCabe, David P.

    2008-01-01

    The current study examined delayed recall of items that had been processed during simple and complex span tasks. Three experiments were reported showing that despite more items being recalled initially from a simple span task (i.e., word span) than a complex span task (i.e., operation span), on a delayed recall test more items were recalled that had initially been processed during the complex span task. This delayed recall advantage for items processed during complex span tasks persisted when...

  17. Extinction chronology of the woolly rhinoceros Coelodonta antiquitatis in the context of late Quaternary megafaunal extinctions in northern Eurasia

    Science.gov (United States)

    Stuart, Anthony J.; Lister, Adrian M.

    2012-09-01

    Megafaunal extinctions in northern Eurasia (excluding Mediterranean islands) since the Last Interglacial claimed about 37% of species with body weights >44 kg. Here we review the dating evidence for the timings of these extinctions, which were staggered over tens of millennia. Moreover, individual species disappeared at different times in different geographical areas. For example, cave bear probably disappeared ca. 30.5-28.5 ka, at approximately the onset of GS-3 (beginning of 'LGM'), whereas cave lion survived until the Lateglacial ca 14 ka. Others survived into the Holocene: woolly mammoth until ca 10.7 ka in the New Siberian Islands and ca 4 ka on Wrangel Island, giant deer to at least 7.7 ka in western Siberia and European Russia. It is evident that climatic and vegetational changes had major impacts on species' ranges, and moreover the contrasting chronologies and geographical range contractions are consistent with environmental drivers relating to their differing ecologies. However, the possible role of humans in this process has still to be satisfactorily explored. We present a detailed review of the radiocarbon record and extinction chronology of an exclusively northern Eurasian species, the woolly rhinoceros Coelodonta antiquitatis, an animal adapted to feeding on low-growing herbaceous vegetation and a dry climate with minimal snowfall. During the Last Glacial the overall (time-averaged) range of C. antiquitatis extended across most of northern Eurasia, but the species failed to reach North America. On the basis of 233 ultrafiltered AMS radiocarbon dates, together with 50 others which pass our auditing criteria, we reconstruct a detailed chronology for this species. C. antiquitatis was widespread over most of the time span covered by radiocarbon dating, but from ca 35 ka (calibrated) it apparently contracted towards the east, culminating in its probable extinction ca 14 ka, with the latest dates from north-eastern Siberia. It disappeared from Britain, at

  18. DNA damage markers in dermal fibroblasts in vitro reflect chronological donor age

    DEFF Research Database (Denmark)

    Waaijer, Mariëtte E C; Croco, Eleonora; Westendorp, Rudi G J; Slagboom, P Eline; Sedivy, John M; Lorenzini, Antonello; Maier, Andrea B

    2016-01-01

    The aging process is accompanied by an accumulation of cellular damage, which compromises the viability and function of cells and tissues. We aim to further explore the association between in vitro DNA damage markers and the chronological age of the donor, as well as long-lived family membership...... damage markers and long-lived family membership or cardiovascular disease. Results were comparable when fibroblasts were stressed in vitro with rotenone. In conclusion, we found that DNA damage foci of cultured fibroblasts are significantly associated with the chronological age, but not biological age...

  19. Burnup span sensitivity analysis of different burnup coupling schemes

    International Nuclear Information System (INIS)

    Highlights: ► The objective of this work is the burnup span sensitivity analysis of different coupling schemes. ► Three kinds of schemes have been implemented in a new MCNP–ORIGEN linkage program. ► Two kinds of schemes are based predictor–corrector technique and the third is based on Euler explicit method. ► The analysis showed that the predictor–corrector approach better accounts for nonlinear behavior of burnup. ► It is sufficiently good to use the Euler method at small spans but for large spans use of second order scheme is mandatory. - Abstract: The analysis of core composition changes is complicated by the fact that the time and spatial variations in isotopic composition depend on the neutron flux distribution and vice versa. Fortunately, changes in core composition occur relatively slowly and hence the burnup analysis can be performed by dividing the burnup period into some burnup spans and assuming that the averaged flux and cross sections are constant during each burn up span. The burnup span sensitivity analysis attempts to find how much the burnup spans could be increased without any significant change in results. This goal has been achieved by developing a new MCNP–ORIGEN linkage program named MOBC (MCNP–ORIGEN Burnup Calculation). Three kinds of coupling scheme have been implemented in MOBC. Two of these are based on second order predictor–corrector technique and enable us to choose larger time steps, whilst the third one is based on Euler explicit first order method and is faster than the other two. The validity of the developed program has been evaluated by the code vs. code comparison technique. Two different types of codes are employed. The first one is based on deterministic two dimensional transport method, like CASMO-4 and HELIOS codes, and the second one is based on Monte Carlo method, like MCODE code. Only one coupling technique is employed in each of these state of the art codes, while the MOBC excels in its ability to

  20. Design and operational considerations for unsupported offshore pipeline spans

    Energy Technology Data Exchange (ETDEWEB)

    Shah, B.C.; White, C.N.; Rippon, I.J.

    1988-05-01

    Design and operational considerations have been examined in determining the significance of unsupported offshore pipeline spans that may develop during pipeline installation or field operation. Allowable unsupported span lengths determined during design are generally based on strict code compliance and a design foundation encompassing the worst possible environmental and operational loads. During operation, however, unsupported spans develop beyond the allowable limits, perhaps as a result of various unforseen local conditions. Applying original design criteria is likely to result in cost-prohibitive repair predictions, while lack of action may result in loss of production. Without the design code requirements of an existing or a proposed pipeline system being violated, realistically safe design can be approached through evaluation of the sensitivity of the key design parameters. Priorities for remedial repair of the unsupported spans can be established for the pipelines in service while operating constraints, budget, and schedule are recognized. On the basis of periodic surveys, properly formatted survey data, and reanalysis of the design parameters, pipeline span repair cost estimates and schedules can be appreciably reduced. Similar principles can be applied to a pipeline in planning and design stages to ensure a safe operating design and to eliminate an uneconomically conservative design. These design and operational considerations are illustrated through a case study.

  1. Development of the NTF-117S Semi-Span Balance

    Science.gov (United States)

    Lynn, Keith C.

    2010-01-01

    A new high-capacity semi-span force and moment balance has recently been developed for use at the National Transonic Facility at the NASA Langley Research Center. This new semi-span balance provides the NTF a new measurement capability that will support testing of semi-span test models at transonic high-lift testing regimes. Future testing utilizing this new balance capability will include active circulation control and propulsion simulation testing of semi-span transonic wing models. The NTF has recently implemented a new highpressure air delivery station that will provide both high and low mass flow pressure lines that are routed out to the semi-span models via a set high/low pressure bellows that are indirectly linked to the metric end of the NTF-117S balance. A new check-load stand is currently being developed to provide the NTF with an in-house capability that will allow for performing check-loads on the NTF-117S balance in order to determine the pressure tare affects on the overall performance of the balance. An experimental design is being developed that will allow for experimentally assessing the static pressure tare affects on the balance performance.

  2. The Role of Covert Retrieval in Working Memory Span Tasks: Evidence from Delayed Recall Tests

    Science.gov (United States)

    McCabe, David P.

    2008-01-01

    The current study examined delayed recall of items that had been processed during simple and complex span tasks. Three experiments were reported showing that despite more items being recalled initially from a simple span task (i.e., word span) than a complex span task (i.e., operation span), on a delayed recall test more items were recalled that…

  3. Network access to PCDS (SPAN, ESN, SESNET, ARPANET)

    Science.gov (United States)

    Green, J.

    1986-01-01

    One of the major goals of the National Space Science Data Center is to increase access to NASA data systems by enhancing networking activities. The activities are centered around three basic networking systems: the Space Physics Analysis Network (SPAN); the Earth Science Network (ESN); and the NASA Packet Switched System (NPSS). Each system is described, linkages among systems are explained, and future plans are announced. The inclusion of several new climate nodes on SPAN or ESN are also mentioned. Presently, the Pilot Climate Data System is accessible through SPAN and will be accessible through NPSS by summer and ESN by the end of 1986. Ambitious plans for implementation are underway. The implementation of these plans will represent a major advance in the utilization and accessibility of data worldwide.

  4. Advanced aerostatic analysis of long-span suspension bridges

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    As the span length of suspension bridges increases, the diameter of cables and thus the wind load acting on them, the nonlinear wind-structure interaction and the wind speed spatial non-uniformity all increase consequently, which may have unnegligible influence on the aerostatic behavior of long-span suspension bridges. In this work, a method of advanced aerostatic analysis is presented firstly by considering the geometric nonlinearity, the nonlinear wind-structures and wind speed spatial non-uniformity. By taking the Runyang Bridge over the Yangtze River as example, effects of the nonlinear wind-structure interaction, wind speed spatial non-uniformity, and the cable's wind load on the aerostatic behavior of the bridge are investigated analytically. The results showed that these factors all have important influence on the aerostatic behavior, and should be considered in the aerostatic analysis of long and particularly super long-span suspension bridges.

  5. Assistant pullback technique for main span closure of Sutong Bridge

    Institute of Scientific and Technical Information of China (English)

    Chen Ming; Luo Chengbin; Wu Qihe; Zhang Yongtao; You Xinpeng

    2009-01-01

    Sutong Bridge is a cable-stayed steel box girder bridge with a main span of 1 088 m. The erection of upper structure adopts geometry control method and requires no change to the unit's size and the structure's none-stress geometry. Before main span closure, the cantilever of girder reaches 540.8 m, the structure state is noticeably influenced by external circumstances, the main span closure face great difficulty. By abstracting the advantage of the pullback method abroad and the domestic temperature-cutting method, a new assistant pullback method have put forward and bring into practice actually. In this paper, the analysis key point of practice conditions, key parameter of practice, main measures of the method and the performance is introduced.

  6. Counting Plane Graphs: Perfect Matchings, Spanning Cycles, and Kasteleyn's Technique

    CERN Document Server

    Sharir, Micha; Welzl, Emo

    2011-01-01

    We derive improved upper bounds on the number of crossing-free straight-edge spanning cycles (also known as Hamiltonian tours and simple polygonizations) that can be embedded over any specific set of $N$ points in the plane. More specifically, we bound the ratio between the number of spanning cycles (or perfect matchings) that can be embedded over a point set and the number of triangulations that can be embedded over it. The respective bounds are $O(1.8181^N)$ for cycles and $O(1.1067^N)$ for matchings. These imply a new upper bound of $O(54.543^N)$ on the number of crossing-free straight-edge spanning cycles that can be embedded over any specific set of $N$ points in the plane (improving upon the previous best upper bound $O(68.664^N)$). Our analysis is based on Kasteleyn's linear algebra technique.

  7. POSTMENOPAUSAL BLEEDING: HISTOPATHOLOGICAL SPECTRUM AND ASSOCIATION WITH AGE AND CLEAR SPAN: CASE SERIES OF 328 CASES

    Directory of Open Access Journals (Sweden)

    Ruchita

    2014-06-01

    Full Text Available : Introduction: Postmenopausal bleeding is defined as vaginal bleeding occurring after twelve months of amenorrhea in a woman of the age where the menopause can be expected. With increase in life expectancy, a larger proportion of female population will be in postmenopausal age group; hence, the incidence of postmenopausal bleeding is expected to increase. AIM: We studied the prevalence of malignancy as well as the histopathological spectrum of genital tract lesions in cases of postmenopausal bleeding. The association between age, period between cessation of menses and onset of bleeding per vaginum (clear span was also studied. RESULTS: Malignant causes were more common (58.5% than benign causes and included cervical carcinoma, malignant uterine tumors (13.1%, carcinoma vagina (4.3%, malignant ovarian tumors (5.5%, carcinoma vulva (0.9% and carcinoma fallopian tube (0.3%. Squamous cell carcinoma was the commonest among cervical malignancies. The benign causes included polyps (16.5%, endometrial hyperplasia (4.9%, adenomyosis (2.7%, atrophic endometrium (2.4%, cervicitis (2.1%, leiomyoma (1.8%, proliferative endometrium (1.5%, endometritis (1.5%, secretory endometrium (1.2%, retained IUCD (0.9% and uterovaginal prolapse (0.6%. The likelihood of malignancy increased significantly with advancing age (p-value 0.042. The clear span of cases with malignant tumors was significantly longer than the clear span of cases with benign lesions. Hence, the likelihood of malignancy increased with length of clear span (p-value 0.00809. CONCLUSION: Any postmenopausal patient with vaginal bleeding needs to be investigated thoroughly to determine the cause of the bleeding and should be considered to have abnormal histopathology until proved otherwise

  8. The WAIS Divide deep ice core WD2014 chronology - Part 2: Annual-layer counting (0-31 ka BP)

    Science.gov (United States)

    Sigl, Michael; Fudge, Tyler J.; Winstrup, Mai; Cole-Dai, Jihong; Ferris, David; McConnell, Joseph R.; Taylor, Ken C.; Welten, Kees C.; Woodruff, Thomas E.; Adolphi, Florian; Bisiaux, Marion; Brook, Edward J.; Buizert, Christo; Caffee, Marc W.; Dunbar, Nelia W.; Edwards, Ross; Geng, Lei; Iverson, Nels; Koffman, Bess; Layman, Lawrence; Maselli, Olivia J.; McGwire, Kenneth; Muscheler, Raimund; Nishiizumi, Kunihiko; Pasteris, Daniel R.; Rhodes, Rachael H.; Sowers, Todd A.

    2016-03-01

    We present the WD2014 chronology for the upper part (0-2850 m; 31.2 ka BP) of the West Antarctic Ice Sheet (WAIS) Divide (WD) ice core. The chronology is based on counting of annual layers observed in the chemical, dust and electrical conductivity records. These layers are caused by seasonal changes in the source, transport, and deposition of aerosols. The measurements were interpreted manually and with the aid of two automated methods. We validated the chronology by comparing to two high-accuracy, absolutely dated chronologies. For the Holocene, the cosmogenic isotope records of 10Be from WAIS Divide and 14C for IntCal13 demonstrated that WD2014 was consistently accurate to better than 0.5 % of the age. For the glacial period, comparisons to the Hulu Cave chronology demonstrated that WD2014 had an accuracy of better than 1 % of the age at three abrupt climate change events between 27 and 31 ka. WD2014 has consistently younger ages than Greenland ice core chronologies during most of the Holocene. For the Younger Dryas-Preboreal transition (11.595 ka; 24 years younger) and the Bølling-Allerød Warming (14.621 ka; 7 years younger), WD2014 ages are within the combined uncertainties of the timescales. Given its high accuracy, WD2014 can become a reference chronology for the Southern Hemisphere, with synchronization to other chronologies feasible using high-quality proxies of volcanism, solar activity, atmospheric mineral dust, and atmospheric methane concentrations.

  9. Tree-Ring Chronology of Pedunculate Oak (Quercus robur and its Potential for Development of Dendrochronological Research in Croatia

    Directory of Open Access Journals (Sweden)

    Katarina Čufar

    2014-06-01

    Full Text Available We present the local tree-ring chronology of pedunculate oak (Qercus robur from Kobiljak near Zagreb, Croatia (16º09’ E, 45º49’ N, 140 m a.s.l.. The chronology is based on 17 trees and is 127 years long and covers the period of 1883-2009. The well replicated part of the residual version of the ARSTAN chronology with SSS>0.80 (interval of 88 years, period 1922-2009 was used for dendroclimatological analysis, which showed that June precipitation has positive and temperature has negative effect on tree-ring variation. Comparison with 40 available oak chronologies from the surrounding countries confi rmed its good teleconnection with 2 local oak chronologies from Austria, 2 from Hungary, and 3 from Slovenia. It also exhibits good heteroconnection, i.e. similarity with chronologies of beech (Fagus sylvatica, from various sites in Slovenia. The similarities can be ascribed to response to common climatic factors. The results indicate that the chronology could be a good reference point for constructing a longer regional chronology in Croatia and surrounding countries, which could be used for different purposes including dating of objects of cultural heritage.

  10. Innovative configurations for long-span suspension bridges

    OpenAIRE

    Bartoli, G.; P. D’Asdia; S. Febo; C. Mannini; S. Noè; L. Procino

    2009-01-01

    This paper reports the results of a piece of research about long-span suspension bridges with multiple-box girder steel deck characterized by low drag coefficient and high aeroelastic stability. For this type of bridges, by increasing the span length, the contribution to the stiffness of the suspension cables becomes dominant with respect to that of the deck, so that the ratio of the frequency of the first torsional mode to the frequency of the first vertical bending mode approaches unity, wh...

  11. Planetary Environments and Origins of Life

    Directory of Open Access Journals (Sweden)

    Ollivier Marc

    2014-02-01

    Full Text Available The present strategies proposed for the search for the origins of life and for extra-terrestrial life are mainly based on Earth-life and its adaptation along geological eras to the Earth environment. These strategies should however face the difficulty that one cannot as yet accurately date the appearance of life on Earth, and consequently one cannot identify a chronology of phenomena related to the transition from the non-living to the living and the dependence of these phenomena on the Earth environment. In this paper, we present new approaches to search for the origins of life on the Earth and next, for life on exoplanets. This study is based on our experience gained at the head of the CNRSc interdisciplinary research initiative "Environnements Planétaires et Origines de la Vie (EPOVd, and on the analysis of the projects the initiative funded.

  12. The double-body glyphs and palaeographic chronology in the rongorongo script

    DEFF Research Database (Denmark)

    Wieczorek, Rafal

    2011-01-01

    . A reading of the related literature shows more scribal differences in other rongorongo glyphs as well. By combining various scribal differences together with the analysis of hollow-belly and 099/522 glyphs, most of the existing rongorongo inscriptions can be classified into a chronological list of texts...

  13. Chronological and subjective age differences in flourishing mental health and major depressive episode.

    NARCIS (Netherlands)

    Keyes, C.L.M.; Westerhof, G.J.

    2012-01-01

    Mental health is more than the absence of psychopathology, but few studies use positive mental health along with a measure of past year major depressive episode (MDE). This study addresses this gap by investigating the association of MDE and flourishing mental health (FMH) with chronological age and

  14. Legal Recognition of Same-Sex Couples in the Countries of the World: a Chronological Overview

    OpenAIRE

    Waaldijk, C.; Marsh, V

    2011-01-01

    Chronological overview of countries (and parts of countries) that have taken some major steps in legally recognising same-sex couples: legal recognition of non-registered same-sex cohabitation, introduction of a form of registered partnership, opening up of adoption and/or marriage for same-sex partners.

  15. A complete chronological bibliography of the journal 'Research on Language and Social Interaction', 1987-2014

    DEFF Research Database (Denmark)

    Nevile, Maurice Richard

    2015-01-01

    This list presents, in chronological order, all items published in the journal ROLSI. The list makes it easier to find specific items, or to track and search for authors, analytic interests and phenomena, settings and situations, or data languages, etc. The list begins at 1987, when the journal...

  16. Testing OSL failures against a regional glaciation chronology from southern Scandinavia

    DEFF Research Database (Denmark)

    Houmark-Nielsen, Michael

    2008-01-01

    Scandinavia agree with the glaciation chronology predicted by numerical and relative ages, but not all. Overestimation of the expected timing seems to arise from an inherited signal acquired prior to the latest depositional episode. Here, the geological context is examined for solifluction deposits that cap...

  17. Synchronizing ice cores from the Renland and Agassiz ice caps to the Greenland Ice Core Chronology

    DEFF Research Database (Denmark)

    Vinther, Bo Møllesøe; Clausen, Henrik Brink; Fischer, D. A.; Koerner, R. M.; Johnsen, Sigfus Johann; Andersen, Katrine Krogh; Dahl-Jensen, Dorthe; Rasmussen, Sune Olander; Steffensen, Jørgen Peder; Svensson, Anders

    Four ice cores from the Agassiz ice cap in the Canadian high arctic and one ice core from the Renland ice cap in eastern Greenland have been synchronized to the Greenland Ice Core Chronology 2005 (GICC05) which is based on annual layer counts in the DYE-3, GRIP and NGRIP ice cores. Volcanic...

  18. The absolute chronology and thermal processing of solids in the solar protoplanetary disk

    DEFF Research Database (Denmark)

    Connelly, James Norman; Bizzarro, Martin; Krot, Alexander N.; Nordlund, Åke; Wielandt, Daniel Kim Peel; Ivanova, Marina A.

    2012-01-01

    Transient heating events that formed calcium-aluminum - rich inclusions (CAIs) and chondrules are fundamental processes in the evolution of the solar protoplanetary disk, but their chronology is not understood. Using U-corrected Pb-Pb dating, we determined absolute ages of individual CAIs and...

  19. You Can't Play That: A Selective Chronology of Banned Music: 1850-1991.

    Science.gov (United States)

    Volz, Edward J.

    1991-01-01

    Discussion of music censorship provides a chronology of banned music from 1850 to the present. Highlights include reasons for music censorship, including lyrics that concern politics, sex, drugs, or death; rewriting song lyrics; radio air play versus sales; warning labels; First Amendment principles; and suggestions to defuse censorship in…

  20. Temperature-sensitive Tien Shan tree ring chronologies show multi-centennial growth trends

    Energy Technology Data Exchange (ETDEWEB)

    Esper, J. [Swiss Federal Research Institute WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Shiyatov, S.G.; Mazepa, V.S. [Institute of Plant and Animal Ecology, Ural Division of Russian Academy of Sciences, 8 Marta Street 202, 620144 Ekaterinburg (Russian Federation); Wilson, R.J.S. [School of GeoSciences, Grant Institute, Edinburgh University, West Mains Road, Edinburgh EH9 3JW (United Kingdom); Graybill, D.A.; Funkhouser, G. [Laboratory of Tree-Ring Research, University of Arizona, Tucson, Arizona 85721 (United States)

    2003-12-01

    Two millennia-length juniper ring width chronologies, processed to preserve multi-centennial growth trends, are presented for the Alai Range of the western Tien Shan in Kirghizia. The chronologies average the information from seven near-timberline sampling sites, and likely reflect summer temperature variation. For comparison, chronologies are also built using standard dendrochronological techniques. We briefly discuss some qualities of these ''inter-decadal'' records, and show the low frequency components removed by the standardization process include a long-term negative trend in the first half of the last millennium and a long-term positive trend since about AD 1800. The multi-centennial scale Alai Range chronologies, where these trends are retained, are both systematically biased (but in an opposite sense) in their low frequency domains. Nevertheless, they represent the best constraints and estimates of long-term summer temperature variation, and reflect the Medieval Warm Period, the Little Ice Age, and a period of warming since about the middle of the nineteenth century. (orig.)

  1. The effects of chronological age and size on toxicity of zinc to juvenile brown trout

    Science.gov (United States)

    A series of toxicity tests were conducted to investigate the role of chronological age and organism weight on zinc tolerance in juvenile brown trout (Salmo trutta). Four different incubation temperatures were used to control the maturation of the juveniles prior to zinc exposure...

  2. WD2014: A new reference chronology for ice cores from Antarctica?

    Science.gov (United States)

    Sigl, Michael; McConnell, Joseph R.; Winstrup, Mai; Fudge, Taylor J.; Cole-Dai, Jihong; Ferris, David; Taylor, Kendrick; Buizert, Christo; Rhodes, Rachael; McGwire, Ken; Welten, Kees C.; Woodruff, Thomas E.; Dunbar, Nelia; Iverson, Nels; Maselli, Olivia J.; Pasteris, Daniel R.; Muscheler, Raimund

    2015-04-01

    Here we present a chronology (WD2014) for the upper part (0-2850 m, 31.2 ka BP) of the West Antarctic Ice Sheet (WAIS)-Divide ice core which is based on layer counting of distinctive annual cycles preserved in the elemental, chemical and electrical conductivity records. These cycles are caused by the seasonally varying impurity concentrations in snowfall reflecting source strength of emissions, transport and deposition efficiency. A new ice core chronology has been developed using manual interpretation as well as by using a layer detection algorithm based on Hidden Markov Models taking advantage of the large suite of sub-annually resolved and co-registered aerosol records from high-resolution continuous measurements. The age model is validated against the absolute dated radiocarbon calibration curve IntCal13 using ice-core Be-10 measurements for proxy synchronization. These records reveal an unprecedented accuracy of the new ice core chronology since the Last Glacial Maximum. The new chronology can become a reference chronology for ice cores with synchronization to other ice cores achievable through the unique high-resolution sulfur record indicating hundreds of volcanic signals common to many other deep ice cores in Antarctica. A developing tephra framework for ice cores from West Antarctica will allow to better integrating Antarctic ice cores and the marine and terrestrial records from the southern hemisphere in the future, thus gaining a detailed chronologic picture of climatic changes and environmental consequences for the region over the past 31,000 years. This southern hemisphere perspective is a fundamental step in developing a detailed global understanding of the effects of past climate changes, and its implications for the future. Due to a small ice-age gas-age difference (delta-age) at WAIS Divide - because of high annual snowfall rates at this site - and a new high-resolution WAIS CH4 record, this new ice core chronology provides also independent

  3. Quantitative and qualitative approaches to identifying migration chronology in a continental migrant.

    Directory of Open Access Journals (Sweden)

    William S Beatty

    Full Text Available The degree to which extrinsic factors influence migration chronology in North American waterfowl has not been quantified, particularly for dabbling ducks. Previous studies have examined waterfowl migration using various methods, however, quantitative approaches to define avian migration chronology over broad spatio-temporal scales are limited, and the implications for using different approaches have not been assessed. We used movement data from 19 female adult mallards (Anas platyrhynchos equipped with solar-powered global positioning system satellite transmitters to evaluate two individual level approaches for quantifying migration chronology. The first approach defined migration based on individual movements among geopolitical boundaries (state, provincial, international, whereas the second method modeled net displacement as a function of time using nonlinear models. Differences in migration chronologies identified by each of the approaches were examined with analysis of variance. The geopolitical method identified mean autumn migration midpoints at 15 November 2010 and 13 November 2011, whereas the net displacement method identified midpoints at 15 November 2010 and 14 November 2011. The mean midpoints for spring migration were 3 April 2011 and 20 March 2012 using the geopolitical method and 31 March 2011 and 22 March 2012 using the net displacement method. The duration, initiation date, midpoint, and termination date for both autumn and spring migration did not differ between the two individual level approaches. Although we did not detect differences in migration parameters between the different approaches, the net displacement metric offers broad potential to address questions in movement ecology for migrating species. Ultimately, an objective definition of migration chronology will allow researchers to obtain a comprehensive understanding of the extrinsic factors that drive migration at the individual and population levels. As a result

  4. Prayer Life of a Professor

    Science.gov (United States)

    Baesler, E. James

    2009-01-01

    This autoethnographic account describes interconnections among the author's personal prayer life, teaching, and research. The contextual frame for the story includes episodes and observations from a twelve-year span, encompassing postacademic tenure and promotion to the present. The author's prayer is that others might resonate with parts of this…

  5. On the number of spanning trees in random regular graphs

    DEFF Research Database (Denmark)

    Greenhill, Catherine; Kwan, Matthew; Wind, David Kofoed

    2014-01-01

    Let d >= 3 be a fixed integer. We give an asympotic formula for the expected number of spanning trees in a uniformly random d-regular graph with n vertices. (The asymptotics are as n -> infinity, restricted to even n if d is odd.) We also obtain the asymptotic distribution of the number of spanni...

  6. Serial Memory Span Thresholds of Normal and Mentally Retarded Children

    Science.gov (United States)

    Baumeister, Alfred A.

    1974-01-01

    Educable mental retardates and normal grade school students were presented seven classes of materials in both visual and auditory modalities for the determination of immediate memory span thresholds. Major conclusions included auditory presentation produces higher thresholds than visual, and retarded children may employ different processing…

  7. Definition of Measure-theoretic Pressure Using Spanning Sets

    Institute of Scientific and Technical Information of China (English)

    Lian Fa HE; Jin Feng LV; Li Na ZHOU

    2004-01-01

    We introduce a new definition of measure-theoretic pressure for ergodic measures of continuous maps on a compact metric space. This definition is similar to those of topological pressure involving spanning sets. As an application, for C1+α(α> 0) diffeomorphisms of a compact manifold, we study the relationship between the measure-theoretic pressure and the periodic points.

  8. On spanning tree packings of highly edge connected graphs

    OpenAIRE

    Lehner, Florian

    2011-01-01

    We prove a refinement of the tree packing theorem by Tutte/Nash-Williams for finite graphs. This result is used to obtain a similar result for end faithful spanning tree packings in certain infinite graphs and consequently to establish a sufficient Hamiltonicity condition for the line graphs of such graphs.

  9. 1-Skeletons of the Spanning Tree Problems with Additional Constraints

    Directory of Open Access Journals (Sweden)

    V. A. Bondarenko

    2015-10-01

    Full Text Available In this paper, we study polyhedral properties of two spanning tree problems with additional constraints. In the first problem, it is required to find a tree with a minimum sum of edge weights among all spanning trees with the number of leaves less than or equal to a given value. In the second problem, an additional constraint is the assumption that the degree of all nodes of the spanning tree does not exceed a given value. The recognition versions of both problems are NP-complete. We consider polytopes of these problems and their 1-skeletons. We prove that in both cases it is a NP-complete problem to determine whether the vertices of 1-skeleton are adjacent. Although it is possible to obtain a superpolynomial lower bounds on the clique numbers of these graphs. These values characterize the time complexity in a broad class of algorithms based on linear comparisons. The results indicate a fundamental difference between combinatorial and geometric properties of the considered problems from the classical minimum spanning tree problem.

  10. Rapid increase in cosmogenic 14C in AD 775 measured in New Zealand kauri trees indicates short-lived increase in 14C production spanning both hemispheres

    Science.gov (United States)

    Güttler, D.; Adolphi, F.; Beer, J.; Bleicher, N.; Boswijk, G.; Christl, M.; Hogg, A.; Palmer, J.; Vockenhuber, C.; Wacker, L.; Wunder, J.

    2015-02-01

    In 2012, Miyake et al. reported a sudden and strong increase of the atmospheric radiocarbon (14C) content in Japanese cedar trees of 1.2% between AD 774 and 775. While their findings were quickly confirmed by a German oak chronology for the Northern Hemisphere (NH), the question remained if the effect was seen in both hemispheres. Here we present the first annually resolved Southern Hemisphere (SH) 14C record spanning the interval AD 760-787, using New Zealand kauri (Agathis australis) chronology wood. An almost identical distinct increase compared to Northern Hemisphere data was observed, suggesting a cosmic event with globally uniform impact as a potential cause for the increase. Deploying a carbon cycle box model a worldwide averaged net 14C production of 2.2 ×108 14C atoms cm-2 was estimated, which is 3.7 times higher than the average annual 14C production. The immediate appearance of the event in tree rings on both hemispheres suggests a short duration event of significantly less than 1 yr.

  11. WildSpan: mining structured motifs from protein sequences

    Directory of Open Access Journals (Sweden)

    Chen Chien-Yu

    2011-03-01

    Full Text Available Abstract Background Automatic extraction of motifs from biological sequences is an important research problem in study of molecular biology. For proteins, it is desired to discover sequence motifs containing a large number of wildcard symbols, as the residues associated with functional sites are usually largely separated in sequences. Discovering such patterns is time-consuming because abundant combinations exist when long gaps (a gap consists of one or more successive wildcards are considered. Mining algorithms often employ constraints to narrow down the search space in order to increase efficiency. However, improper constraint models might degrade the sensitivity and specificity of the motifs discovered by computational methods. We previously proposed a new constraint model to handle large wildcard regions for discovering functional motifs of proteins. The patterns that satisfy the proposed constraint model are called W-patterns. A W-pattern is a structured motif that groups motif symbols into pattern blocks interleaved with large irregular gaps. Considering large gaps reflects the fact that functional residues are not always from a single region of protein sequences, and restricting motif symbols into clusters corresponds to the observation that short motifs are frequently present within protein families. To efficiently discover W-patterns for large-scale sequence annotation and function prediction, this paper first formally introduces the problem to solve and proposes an algorithm named WildSpan (sequential pattern mining across large wildcard regions that incorporates several pruning strategies to largely reduce the mining cost. Results WildSpan is shown to efficiently find W-patterns containing conserved residues that are far separated in sequences. We conducted experiments with two mining strategies, protein-based and family-based mining, to evaluate the usefulness of W-patterns and performance of WildSpan. The protein-based mining mode

  12. The Chronology of Asteroid Accretion, Differentiation, and Secondary Mineralization

    Science.gov (United States)

    Nyquist, L. E.; Kleine, T.; Shih, C.-Y.; Reese, Y. D.

    2008-01-01

    We evaluate initial (Al-26/Al-27)(sub I), (Mn-53/Mn-55)(sub I), (Hf-182/Hf-180)(sub I), and Pb-207/Pb-206 ages for igneous differentiated meteorites and chondrules from ordinary chondrites for consistency with radioactive decay of the parent nuclides within a common, closed isotopic system, i.e., the early solar nebula. We find that the relative abundances of Al-26, Mn-53, and Hf-182, here denoted by I(Al)(sub CAI, I(Mn)(sub CAI) and I(Hf)(sub CAI), are consistent with decay from common initial values for the bulk solar system. I(Mn)(sub CAI) and I(Hf)(sub CAI) = 9.1+/-1.7 x 10(exp -6) and 1.06+/-0.09 x 10(exp -6) respectively, correspond to the canonical value of I(Al)(sub CAI) = 5.1 x 10(exp -5). I(Hf)(sub CAI) thus determined is consistent with I(Hf)(sub CAI) = 1.003+/-0.045 x 10(exp -6) directly determined in separate work. I(Mn)(sub CAI) is within error of the lowest value directly determined for CAI. We suggest that erratically higher values directly determined for CAI in carbonaceous chondrites reflect proton irradiation of unaccreted CAIs by the early Sun after other asteroids destined for melting by Al-26 decay had already accreted. The Mn-53 incorporated within such asteroids would have been shielded from further "local" spallogenic contributions. The relative abundances of the short-lived nuclides are less consistent with the Pb-207/Pb-206 ages of the corresponding materials with the best consistency being obtained between (Hf-182/Hf-180)(sub I) and Pb-207/Pb-206 ages of angrites. (Hf-182/Hf-180)(sub I) decreases with decreasing Pb-207/Pb-206 ages at the rate expected from the 8.90+/-0.09 Ma half-life of Hf-182. However, the model "CAI age" thus determined, T(sub CAI,Mn-W) = 4568.6+/-0.7 Ma, is older than the commonly accepted directly measured value T(sub CAI) = 4567.l+/-0.2 Ma. I(Al)(sub I), and (Mn-53/Mn-55)(sub I) are less consistent with Pb-207/Pb-206 ages, but determine T(sub CAI, Mn-Cr) = 4568.3+/-0.5 Ma relative to I(AI)(sub CAI)= 5.1 x 10(exp -5

  13. Health Across the Life Span in the United States and England

    OpenAIRE

    Martinson, Melissa L.; Teitler, Julien O.; Reichman, Nancy E.

    2011-01-01

    This study systematically compared health indicators in the United States and England from childhood through old age (ages 0–80 years). Data were from the 1999–2006 National Health and Nutrition Examination Survey for the United States (n = 39,849) and the 2003–2006 Health Survey for England (n = 69,084). Individuals in the United States have higher rates of most chronic diseases and markers of disease than their same-age counterparts in England. Differences at young ages are as large as thos...

  14. Calorie restriction causes healthy life span extension in the filamentous fungus Podospora anserina

    NARCIS (Netherlands)

    Diepeningen, van A.D.; Maas, M.F.P.M.; Huberts, D.H.E.W.; Goedbloed, D.J.; Engelmoer, D.J.P.; Slakhorst, S.M.; Koopmanschap, A.B.; Krause, F.; Dencher, N.A.; Sellem, C.H.; Sainsard-Chanet, A.; Hoekstra, R.F.; Debets, A.J.M.

    2010-01-01

    Although most fungi appear to be immortal, some show systemic senescence within a distinct time frame. Podospora anserina for example shows an irreversible growth arrest within weeks of culturing associated with a destabilization of the mitochondrial genome. Here, we show that calorie restriction (C

  15. Travelling against the Current: An Examination of Upstream and Downstream Educational Interventions across the Life Span

    Science.gov (United States)

    Silburn, Jenny; Box, Geraldine

    2008-01-01

    Current social and economic circumstances are presenting universities with a more diverse general student intake whose support needs are increasingly similar to those of traditionally defined equity groups. This paper examines a Murdoch University equity program to demonstrate that simply increasing access does not always translate into increased…

  16. Daughter cells of Saccharomyces cerevisiae from old mothers display a reduced life span

    OpenAIRE

    1994-01-01

    The yeast Saccharomyces cerevisiae typically divides asymmetrically to give a large mother cell and a smaller daughter cell. As mother cells become old, they enlarge and produce daughter cells that are larger than daughters derived from young mother cells. We found that occasional daughter cells were indistinguishable in size from their mothers, giving rise to a symmetric division. The frequency of symmetric divisions became greater as mother cells aged and reached a maximum occurrence of 30%...

  17. Differential Effects of Emotional Information on Interference Task Performance across the Life Span

    Directory of Open Access Journals (Sweden)

    Haley M LaMonica

    2010-09-01

    Full Text Available While functioning in multiple domains declines with age, emotional regulation appears to remain preserved in older adults. The Emotion Inhibition (Emotional Stroop Test requires participants to name the ink color in which neutrally- and emotionally-valenced words are printed. It was employed in the current investigation as a measure of affective regulation in the context of an interference task in relation to age. Results demonstrated that while participants ranging from 20 to 50 years of age performed significantly worse on the emotion Stroop Inhibition relative to the neutral Stroop Inhibition condition, subjects over 60 years of age displayed the converse of this pattern, performing better on the emotion than the neutral condition, suggesting that they are less affected by the emotional impact of the positive and negative words used in the former condition. This pattern of age-related change in the ability to manage emotion may be related to blunting of affective signaling in limbic structures or, at the psychological level, focusing on emotional regulation.

  18. Differential Effects of Emotional Information on Interference Task Performance across the Life Span

    OpenAIRE

    LaMonica, Haley M.; Keefe, Richard S.E.; Harvey, Philip D.; Gold, James M.; Goldberg, Terry E.

    2010-01-01

    While functioning in multiple domains declines with age, emotional regulation appears to remain preserved in older adults. The Emotion Inhibition (Emotional Stroop) Test requires participants to name the ink color in which neutrally- and emotionally-valenced words are printed. It was employed in the current investigation as a measure of affective regulation in the context of an interference task in relation to age. Results demonstrated that while participants ranging from 20 to 50 years of ag...

  19. Differential Effects of Emotional Information on Interference Task Performance Across the Life Span

    OpenAIRE

    LaMonica, Haley M.; Keefe, Richard S.E.; Harvey, Philip D.; Gold, James M.; Goldberg, Terry E.

    2010-01-01

    While functioning in multiple domains declines with age, emotional regulation appears to remain preserved in older adults. The Emotion Inhibition (Emotional Stroop) Test requires participants to name the ink color in which neutrally and emotionally valenced words are printed. It was employed in the current investigation as a measure of affective regulation in the context of an interference task in relation to age. Results demonstrated that while participants ranging from 20 to 50 years of age...

  20. The Hope and Promise of Career Life-Span Counselor and Therapist Development.

    Science.gov (United States)

    Skovholt, Thomas M.; Ronnestad, Michael H.

    2003-01-01

    Reformulation of the findings of a cross-sectional longitudinal study of 100 counselors and therapists resulted in 14 themes and a 6-phase model: lay helper, beginning student, advanced student, novice professional, experienced professional, and senior professional. Results show that experiences in personal and professional domains are significant…