Science.gov

Sample records for age range studied

  1. Procrastination, Distress and Life Satisfaction across the Age Range - A German Representative Community Study.

    PubMed

    Beutel, Manfred E; Klein, Eva M; Aufenanger, Stefan; Brähler, Elmar; Dreier, Michael; Müller, Kai W; Quiring, Oliver; Reinecke, Leonard; Schmutzer, Gabriele; Stark, Birgit; Wölfling, Klaus

    2016-01-01

    Addressing the lack of population-based data the purpose of this representative study was to assess procrastination and its associations with distress and life satisfaction across the life span. A representative German community sample (1,350 women; 1,177 men) between the ages of 14 and 95 years was examined by the short form of the General Procrastination Scale (GPS-K; 1) and standardized scales of perceived stress, depression, anxiety, fatigue and life satisfaction. As hypothesized, procrastination was highest in the youngest cohort (14-29 years). Only in the youngest and most procrastinating cohort (aged 14 to 29 years), men procrastinated more than women. As we had further hypothesized, procrastination was consistently associated with higher stress, more depression, anxiety, fatigue and reduced satisfaction across life domains, especially regarding work and income. Associations were also found with lack of a partnership and unemployment. Findings are discussed with regard to potential developmental and cohort effects. While procrastination appears to be a pervasive indicator for maladjustment, longitudinal analyses in high-risk samples (e.g. late adolescence, unemployment) are needed to identify means and mechanisms of procrastinating.

  2. Procrastination, Distress and Life Satisfaction across the Age Range – A German Representative Community Study

    PubMed Central

    2016-01-01

    Addressing the lack of population-based data the purpose of this representative study was to assess procrastination and its associations with distress and life satisfaction across the life span. A representative German community sample (1,350 women; 1,177 men) between the ages of 14 and 95 years was examined by the short form of the General Procrastination Scale (GPS-K; 1) and standardized scales of perceived stress, depression, anxiety, fatigue and life satisfaction. As hypothesized, procrastination was highest in the youngest cohort (14–29 years). Only in the youngest and most procrastinating cohort (aged 14 to 29 years), men procrastinated more than women. As we had further hypothesized, procrastination was consistently associated with higher stress, more depression, anxiety, fatigue and reduced satisfaction across life domains, especially regarding work and income. Associations were also found with lack of a partnership and unemployment. Findings are discussed with regard to potential developmental and cohort effects. While procrastination appears to be a pervasive indicator for maladjustment, longitudinal analyses in high-risk samples (e.g. late adolescence, unemployment) are needed to identify means and mechanisms of procrastinating. PMID:26871572

  3. Environmental exposure of lead and iron deficit anemia in children age ranged 1-5 years: a cross sectional study.

    PubMed

    Shah, Faheem; Kazi, Tasneem Gul; Afridi, Hassan Imran; Baig, Jameel Ahmed; Khan, Sumaira; Kolachi, Nida Fatima; Wadhwa, Sham Kumar; Shah, Abdul Qadir

    2010-10-15

    Iron (Fe) deficiency is the most common nutritional problem among children and lead (Pb) toxicity is the most common environmental health threat to children all over the world. The objective of this study was to determine blood lead (BPb) levels and prevalence of Fe deficient anemia among 1 to 5year old children attending day care clinic in pediatric ward of civil hospital Karachi, Pakistan. A total of 340 children of both genders participating in this study, were screened for anemia. Among them 215 were anemic and 125 non-anemic. The anemic group was further divided in two groups on the basis of % hemoglobin (Hb), mild (Hb <10g/dL) and severe anemic group (Hb <8g/dL), while non-anemic as referent children (Hb >10g/dL). The blood samples were analysed for Pb and Fe, along with hematological parameters. The result indicated that anemic children had a higher mean values of Pb in blood than referent children with Hb >10g/dL. The Pb levels <100μg/L were detected in 40% referent children while 60% of them had >10μg/dL. The BPb concentration in severe anemic children (53%) was found in the range of 100-200μg/L, whereas 47% had >200μg/L. The significant negative correlations of BPb level with % Hb (r=-0.514 and r=-0.685) and Fe contents (r=-0.522, r=-0.762, p<0.001) were observed in mild and severe anemic children respectively. While positive correlation was observed between BPb and age of both group and genders (r=0.69, p<0.01). The BPb levels were significantly associated with biochemical indices in the blood which have the potential to be used as biomarkers of Pb intoxication and Fe deficient anemia.

  4. The influence of age, anthropometrics and range of motion on the morphometry of the synovial folds of the lateral atlanto-axial joints: a pilot study.

    PubMed

    Webb, Alexandra; Darekar, Angela; Rassoulian, Hamid

    2011-04-01

    The purpose of this study was to investigate the effect of age, anthropometrics and cervical range of motion upon synovial fold volume. Ten healthy female subjects aged 20-40 years were included in the study. Age, height, body mass, dimensions of the head and neck and cervical range of motion of each subject were measured. Magnetic resonance (MR) images of the cervical spine were acquired; the volume of the ventral and dorsal synovial folds of the right and the left lateral atlanto-axial joints was measured using seed growing and thresholding methods. Using Spearman's correlation coefficient, it was determined that there was no correlation between synovial fold volume and age. Synovial fold volume was positively correlated with subject height and neck length but negatively correlated with body mass, body mass index and the circumference of the head and neck. The relationship between synovial fold volume and range of cervical motion varied with the plane of movement. The ability to image the synovial folds of the lateral atlanto-axial joints using MR imaging to determine their normal morphology provides the basis for investigating synovial fold pathology in patients with neck pain and headache.

  5. Reference Range of Platelet Delta Granules in the Pediatric Age Group: An Ultrastructural Study of Platelet Whole Mount Preparations from Healthy Volunteers.

    PubMed

    Sorokin, Victoria; Alkhoury, Razan; Al-Rawabdeh, Sura; Houston, Ronald H; Thornton, David; Kerlin, Bryce; O'Brien, Sarah; Baker, Peter; Boesel, Carl; Uddin, Minhaj; Yin, Han; Kahwash, Samir

    This study sought to determine delta granule normal ranges for children and to validate methodology for the appropriate diagnosis of delta granule deficiency (storage pool disease) by using the whole-mount technique in electron microscopy. Specimens obtained from 40 healthy volunteers (2 months of age through 21 years old, 21 females and 19 males) were tested. Results showed dense granules/platelet (DG/Plt) ranged from 1.78 to 5.25. The 5th percentile was 1.96 DG/Plt with an overall mean ± SEM 3.07 ± 0.12 DG/Plt. In comparison, a previously published lower cutoff value, 3.68 DG/Plt, was significantly higher than the mean from our volunteers (P < 0.0001). We found no variability in dense granules/platelet based on race or sex and no significant variation by age subgroup. Pending wider studies, the value of 2 DG/Plt is a more appropriate lower limit of normal. In the absence of wider studies (in healthy volunteers and patients), laboratories should consider establishing their own reference ranges.

  6. Geographic range size and evolutionary age in birds.

    PubMed Central

    Webb, T J; Gaston, K J

    2000-01-01

    Together with patterns of speciation and extinction, post-speciation transformations in the range sizes of individual species determine the form of contemporary species range-size distributions. However, the methodological problems associated with tracking the dynamics of a species' range size over evolutionary time have precluded direct study of such range-size transformations, although indirect evidence has led to several models being proposed describing the form that they might take. Here, we use independently derived molecular data to estimate ages of species in six monophyletic groups of birds, and examine the relationship between species age and global geographic range size. We present strong evidence that avian range sizes are not static over evolutionary time. In addition, it seems that, with the regular exception of certain taxa (for example island endemics and some threatened species), range-size transformations are non-random in birds. In general, range sizes appear to expand relatively rapidly post speciation; subsequently; and perhaps more gradually, they then decline as species age. We discuss these results with reference to the various models of range-size dynamics that have been proposed. PMID:11052534

  7. Parylene C Aging Studies.

    SciTech Connect

    Achyuthan, Komandoor; Sawyer, Patricia Sue.; Mata, Guillermo Adrian; White II, Gregory Von; Bernstein, Robert

    2014-09-01

    Parylene C is used in a device because of its conformable deposition and other advantages. Techniques to study Parylene C aging were developed, and "lessons learned" that could be utilized for future studies are the result of this initial study. Differential Scanning Calorimetry yielded temperature ranges for Parylene C aging as well as post-deposition treatment. Post-deposition techniques are suggested to improve Parylene C performance. Sample preparation was critical to aging regimen. Short-term (%7E40 days) aging experiments with free standing and ceramic-supported Parylene C films highlighted "lessons learned" which stressed further investigations in order to refine sample preparation (film thickness, single sided uniform coating, machine versus laser cutting, annealing time, temperature) and testing issues ("necking") for robust accelerated aging of Parylene C.

  8. When age-progressed images are unreliable: The roles of external features and age range.

    PubMed

    Erickson, William Blake; Lampinen, James Michael; Frowd, Charlie D; Mahoney, Gregory

    2017-03-01

    When children go missing for many years, investigators commission age-progressed images from forensic artists to depict an updated appearance. These images have anecdotal success, and systematic research has found they lead to accurate recognition rates comparable to outdated photos. The present study examines the reliability of age progressions of the same individuals created by different artists. Eight artists first generated age progressions of eight targets across three age ranges. Eighty-five participants then evaluated the similarity of these images against other images depicting the same targets progressed at the same age ranges, viewing either whole faces or faces with external features concealed. Similarities were highest over shorter age ranges and when external features were concealed. Implications drawn from theory and application are discussed.

  9. Is soy intake related to age at onset of menarche? A cross-sectional study among adolescents with a wide range of soy food consumption

    PubMed Central

    2014-01-01

    Background Early onset of menarche may negatively influence the future health of adolescent girls. Several factors affect the timing of menarche but it is not clear if soy foods consumption around pubertal years plays a role; thus, we examined its relation to age at onset of menarche (AOM) in a high soy-consuming population. Methods We conducted a cross-sectional study on 339 girls ages 12–18 years attending middle and high schools near two Seventh-day Adventist universities in California and Michigan using a web-based dietary questionnaire and physical development tool. Soy consumption (categorized as total soy, meat alternatives, tofu/traditional soy, and soy beverages) was estimated from the questionnaire, while AOM was self-reported. Data analyses included descriptive statistics, Cox proportional hazards ratios, Kaplan-Meier curves and Poisson regression with adjustment for relevant confounders. Results Mean (SD) intakes were: total soy,12.9 (14.4) servings/week; meat alternatives, 7.0 (8.9) servings/week; tofu/traditional soy foods, 2.1 (3.8) servings/week; soy beverages, 3.8 (6.3) servings/week. Mean AOM was 12.5 (1.4) y for those who reached menarche. Consumption of total soy and the 3 types of soy foods was not significantly associated with AOM and with the odds for early- or late-AOM. Adjustment for demographic and dietary factors did not change the results. Conclusion Soy intake is not associated with AOM in a population of adolescent girls who have a wide range of, and relatively higher, soy intake than the general US population. Our finding suggests that the increasing popularity of soy in the US may not be associated with AOM. PMID:24889551

  10. Studying aging in Drosophila.

    PubMed

    He, Ying; Jasper, Heinrich

    2014-06-15

    Drosophila melanogaster represents one of the most important genetically accessible model organisms for aging research. Studies in flies have identified single gene mutations that influence lifespan and have characterized endocrine signaling interactions that control homeostasis systemically. Recent studies have focused on the effects of aging on specific tissues and physiological processes, providing a comprehensive picture of age-related tissue dysfunction and the loss of systemic homeostasis. Here we review methodological aspects of this work and highlight technical considerations when using Drosophila to study aging and age-related diseases.

  11. Isotopic ages of rocks in the northern Front Range, Colorado

    USGS Publications Warehouse

    Wilson, Anna B.; Bryant, Bruce

    2006-01-01

    These maps, and the tables that accompany them, are a compilation of isotopic age determinations of rocks and minerals in four 1:100,000 quadrangles in the northern and central Front Range, Colorado. Phanerozoic (primarily Tertiary and Cretaceous) age data are shown on one map; Proterozoic data are on the other. A sample location map is included for ease of matching specific localities and data in the tables to the maps. Several records in the tables were not included in the maps because either there were ambiguous dates or lack of location precluded accurate plotting.

  12. Designing Playful Learning by Using Educational Board Game for Children in the Age Range of 7-12: (A Case Study: Recycling and Waste Separation Education Board Game)

    ERIC Educational Resources Information Center

    Mostowfi, Sara; Mamaghani, Nasser Koleini; Khorramar, Mehdi

    2016-01-01

    Due to a progressive deterioration of our planet and its resources, environmental education has become important and children are required to understand environmental issues at an early ages. So, they can cultivate the positive changes in the future. Over the past decade, many new evaluation methods have developed for evaluating user experience…

  13. Non-parametric estimation of age-related centiles over wide age ranges.

    PubMed

    Pan, H Q; Goldstein, H; Yang, Q

    1990-01-01

    A new method for estimating age-related centile curves has been developed, which is suitable for measurement covering a wide age range. The method was used to calculate weight centile curves of 8995 children from birth to 6 years obtained by the Collaborating Centre for Physical Growth and Psychosocial Development of Children in Shanghai, China.

  14. Comprehensive study on the structure of the BSA from extended-to aged form in wide (2-12) pH range.

    PubMed

    Varga, N; Hornok, V; Sebők, D; Dékány, I

    2016-07-01

    In this work we studied the structure of the bovine serum albumin (BSA) and the protein-ligand interactions since researchers prefer to use them as carriers in drug delivery systems. Systematic study (between pH 2-12, in double distilled water and physiological salt solution) was carried out to determine the changes in the secondary and the tertiary structures of the BSA, the apparent molecular weight (Mw), the size (dLS) and the electrokinetic potential (ζ). At pH 7, the BSA has higher stability in the absence (ζ=-69mV, dLS=2.2nm, A2=1.4×10(-3)mlmol/g(2)) than in the presence of salt solution (ζ=-2.4mV, dLS=5.3nm, A2=-3.2×10(-4)mlmol/g(2)). The Mw strongly depends on the pH and the ionic strength (at pH 3 in the absence of salt, the Mw is 54.6kDa while in the presence of salt is 114kDa) which determines the geometry of the protein. The protein-ligand interactions were characterized by fluorescence (FL) and isothermal microcalorimetry (ITC) methods; these independent techniques provided similar thermodynamic parameters such as the binding constant (K) and the Gibbs free energy (ΔG).

  15. Concrete containment aging study

    SciTech Connect

    Pachner, J.; Tai, T.M.; Naus, D.

    1994-04-01

    In 1989, IAEA initiated a pilot study on the management of aging of nuclear power plant components. The Phase I and II studies of concrete containment are discussed. With the data base, plant owners will be able to review and enhance their existing programs. IAEA will analyze data provided by participating plants and the report is scheduled to be released by late 1994 (final report release mid-1995).

  16. New radiocarbon ages from cirques in Colorado Front Range

    SciTech Connect

    Davis, P.T. . Dept. Natural Science); Birkeland, P.W. . Dept. Geological Science); Caine, N. . Dept. of Geography); Rodbell, D.T. )

    1992-01-01

    The authors recovered sediment cores 3.1 m long from Blue Lake ([approximately]37m water depth, [approximately]3,445m a.s.l., 40[degree]5 minutes 20 seconds N, 105[degree]37 minutes 08 seconds W) and 2.7m long from Lake Dorothy ([approximately]35m water depth, [approximately]3,675m a.s.l., 40[degree]00 minutes 46 seconds N, 105[degree]41 minutes 11 seconds W). A light-weight percussion coring system suspended from perlon ropes was used because of sediment thicknesses, water depths, and ski-backpacking requirements. Lake ice provided a stable coring platform. One purpose of the project is provision of a high-resolution record of environmental change in the subalpine/alpine ecotone during the Holocene, under the auspices of the Niwot Ridge Long-Term Ecological Research program. The sediment cores also provide minimum-limiting radiocarbon ages for deglaciation of cirques and the deposits that impound their tarns. Here the authors report on this second purpose. The Blue Lake core bottomed in sandy, gray, inorganic sediment, presumably glacial diamict. A bulk sample from 2.8--2.9m depth yielded a conventional radiocarbon age of 12,275[+-]345 yrs BP. Thus, ice retreated from the site by 12 ka. Since 12 ka both glacial and rock-glacial sediments have been deposited upvalley; some of these events may be recognized in the core. In contrast, the Lake Dorothy core did not penetrate gray inorganic diamict and is entirely organic-rich. A bulk sample from 2.65--2.7m depth yielded a conventional radiocarbon age of 10,910 [+-] 320 yrs BP. Thus, the moraines impounding the lake are 2--3 times older than suggested by a combination of relative-age methods and one radiocarbon age from surface sediments.

  17. Age is associated with time in therapeutic range for warfarin therapy in patients with atrial fibrillation

    PubMed Central

    da Costa Darrieux, Francisco Carlos; Hachul, Denise Tessariol; Scanavacca, Maurício Ibrahim; Krieger, Jose Eduardo; Pereira, Alexandre Costa; Lima Santos, Paulo Caleb Junior

    2016-01-01

    Background Warfarin is the most prescribed oral anticoagulant used for preventing stroke in patients with atrial fibrillation. Time in the therapeutic range (TTR) has been accepted as the best method to evaluate the quality of warfarin therapy. The main aim of the present study was to evaluate the impact of variables on the time in the therapeutic range for warfarin therapy in patients with atrial fibrillation from a referral cardiovascular hospital. Methods This retrospective study included 443 patients were included (190 patients with age < 65 years and 253 patients with age ≥65 years) from 2011 to 2014 and TTR was computed according to Rosendaal's method. Results Patients with age ≥65 years had higher TTR value (67±22%) compared with patients with < 65 years (60±24%) (p = 0.004). In a linear regression model, only age ≥65 years emerged as a significant predictor of greater TTR values. In multivariate logistic regression model, the variable age ≥65 years was associated with higher OR for having a TTR higher than the median value (OR = 2.17, p < 0.001). Conclusion We suggest that the age influenced TTR through greater drug adherence. Strategies for increasing drug adherence might improve quality of warfarin anticoagulation. PMID:27486984

  18. Towards a method for determining age ranges from faces of juveniles on photographs.

    PubMed

    Cummaudo, M; Guerzoni, M; Gibelli, D; Cigada, A; Obertovà, Z; Ratnayake, M; Poppa, P; Gabriel, P; Ritz-Timme, S; Cattaneo, C

    2014-06-01

    The steady increase in the distribution of juvenile pornographic material in recent years strongly required valid methods for estimating the age of the victims. At the present in fact forensic experts still commonly use the assessment of sexual characteristics by Tanner staging, although they have proven to be too subjective and deceiving for age estimation. The objective of this study, inspired by a previous EU project involving Italy, Germany and Lithuania, is to verify the applicability of certain anthropometric indices of faces in order to determine age and to create a database of facial measurements on a population of children in order to improve face ageing techniques. In this study, 1924 standardized facial images in frontal view and 1921 in lateral view of individuals from 7 age groups (3-5 years, 6-8 years, 9-11 years, 12-14 years, 15-17 years, 18-20 years, 21-24 years) underwent metric analysis. Individuals were all of Caucasoid ancestry and Italian nationality. Eighteen anthropometric indices in the frontal view and five in the lateral view were then calculated from the obtained measurements. Indices showing a correlation with age were ch-ch/ex-ex, ch-ch/pu-pu, en-en/ch-ch and se-sto/ex-ex in the frontal view, se-prn/se-sn, se-prn/se-sto and se-sn/se-sto in the lateral view. All the indices increased with age except for en-en/ch-ch, without relevant differences between males and females. These results provide an interesting starting point not only for placing a photographed face in an age range but also for refining the techniques of face ageing and personal identification.

  19. Denver RTD range extension study. Final report

    SciTech Connect

    Not Available

    1982-06-01

    This final report presents the results obtained in Task 4, Recommendations, of the Battery-Electric Bus Range Extension Study. In the second section of the report, the five range extension techniques, i.e. battery exchange (baseline); hydro-pneumatic regeneration to recover braking energy; fast recharge at the mall terminals; series hybrid: on-board internal combustion engine and generator which changes the battery; and combination of hydropneumatic regeneration and fast recharge. The third section of the report covers the system evaluation factors, rating schemes and facts, boundaries and weights. The results of the system evaluation and MCR Technology recommendations are presented in section four. The last section of the report covers the implementation program outline for the recommended range extension technique.

  20. Design Evolution Study - Aging Options

    SciTech Connect

    P. McDaniel

    2002-04-05

    The purpose of this study is to identify options and issues for aging commercial spent nuclear fuel received for disposal at the Yucca Mountain Mined Geologic Repository. Some early shipments of commercial spent nuclear fuel to the repository may be received with high-heat-output (younger) fuel assemblies that will need to be managed to meet thermal goals for emplacement. The capability to age as much as 40,000 metric tons of heavy metal of commercial spent nuclear he1 would provide more flexibility in the design to manage this younger fuel and to decouple waste receipt and waste emplacement. The following potential aging location options are evaluated: (1) Surface aging at four locations near the North Portal; (2) Subsurface aging in the permanent emplacement drifts; and (3) Subsurface aging in a new subsurface area. The following aging container options are evaluated: (1) Complete Waste Package; (2) Stainless Steel inner liner of the waste package; (3) Dual Purpose Canisters; (4) Multi-Purpose Canisters; and (5) New disposable canister for uncanistered commercial spent nuclear fuel. Each option is compared to a ''Base Case,'' which is the expected normal waste packaging process without aging. A Value Engineering approach is used to score each option against nine technical criteria and rank the options. Open issues with each of the options and suggested future actions are also presented. Costs for aging containers and aging locations are evaluated separately. Capital costs are developed for direct costs and distributable field costs. To the extent practical, unit costs are presented. Indirect costs, operating costs, and total system life cycle costs will be evaluated outside of this study. Three recommendations for aging commercial spent nuclear fuel--subsurface, surface, and combined surface and subsurface are presented for further review in the overall design re-evaluation effort. Options that were evaluated but not recommended are: subsurface aging in a new

  1. Mechanical properties of bulk polydimethylsiloxane for microfluidics over a large range of frequencies and aging times

    NASA Astrophysics Data System (ADS)

    Placet, V.; Delobelle, P.

    2015-03-01

    The dynamic mechanical characterization of polydimethylsiloxane (PDMS) over a large range of frequencies (10-2 < f < 105 Hz) and long aging times at room temperature (4 h < tv < ~60 000 h) has been presented. Three samples with different curing conditions have been studied and three different techniques, dynamic mechanical analysis at different temperatures, nano-indentation and scanning micro-deformation microscopy, have been used. Although the three techniques work at different scales and at different frequencies all the results match the same master curve. As expected, the storage and the loss moduli greatly increase with the frequency. Moreover, these moduli moderately increase with the aging time tv depending on the curing temperature. A simple model which takes the frequency and the aging time into account, and which is based on the Havriliak-Negami model, has been presented and identified. Hence, values of the relaxed and instantaneous moduli at tv = 0 and tv = ∞ are proposed. Only the relaxed moduli depend on the curing conditions and moreover it has been shown that the tangent of the phase lag is independent of the aging time and thus of the curing process.

  2. CO2 laser ranging systems study

    NASA Technical Reports Server (NTRS)

    Filippi, C. A.

    1975-01-01

    The conceptual design and error performance of a CO2 laser ranging system are analyzed. Ranging signal and subsystem processing alternatives are identified, and their comprehensive evaluation yields preferred candidate solutions which are analyzed to derive range and range rate error contributions. The performance results are presented in the form of extensive tables and figures which identify the ranging accuracy compromises as a function of the key system design parameters and subsystem performance indexes. The ranging errors obtained are noted to be within the high accuracy requirements of existing NASA/GSFC missions with a proper system design.

  3. Differential range use between age classes of southern African Bearded Vultures Gypaetus barbatus.

    PubMed

    Krüger, Sonja; Reid, Timothy; Amar, Arjun

    2014-01-01

    Bearded Vulture Gypaetus barbatus movements were investigated in southern Africa to determine whether an individual's age, sex or breeding status influenced its ranging behaviour and to provide the information required to guide conservation activities. Data from satellite transmitters fitted to 18 individuals of four age classes were used to determine range size and use. Because of the nature of the movements of marked individuals, these data could be used to determine the overall foraging range of the entire population, which was estimated to be 51 767 km(2). Although juvenile, immature and sub-adult birds used different parts of the overall range, their combined foraging range was 65% (33 636 km(2)) of the overall range. Average adult home ranges (286 km(2)) were only around 1% the size of the average foraging ranges of non-adults (10 540 -25 985 km(2)), with those of breeding adults being even smaller (95 km(2)). Home ranges of breeding adults did not vary in size between seasons but adults utilized their home range more intensively whilst breeding, moving greater distances during the incubation and chick hatching period. Range size and use increased as non-adults aged. Immatures and sub-adults had larger range sizes during winter, but range use of non-adults did not vary seasonally. Range size and use did not differ between the sexes in any of the age classes. Information on home range size and use enables specific areas within the species' range to be targeted for management planning, education and conservation action.

  4. Differential Range Use between Age Classes of Southern African Bearded Vultures Gypaetus barbatus

    PubMed Central

    Krüger, Sonja; Reid, Timothy; Amar, Arjun

    2014-01-01

    Bearded Vulture Gypaetus barbatus movements were investigated in southern Africa to determine whether an individual's age, sex or breeding status influenced its ranging behaviour and to provide the information required to guide conservation activities. Data from satellite transmitters fitted to 18 individuals of four age classes were used to determine range size and use. Because of the nature of the movements of marked individuals, these data could be used to determine the overall foraging range of the entire population, which was estimated to be 51 767 km2. Although juvenile, immature and sub-adult birds used different parts of the overall range, their combined foraging range was 65% (33 636 km2) of the overall range. Average adult home ranges (286 km2) were only around 1% the size of the average foraging ranges of non-adults (10 540 –25 985 km2), with those of breeding adults being even smaller (95 km2). Home ranges of breeding adults did not vary in size between seasons but adults utilized their home range more intensively whilst breeding, moving greater distances during the incubation and chick hatching period. Range size and use increased as non-adults aged. Immatures and sub-adults had larger range sizes during winter, but range use of non-adults did not vary seasonally. Range size and use did not differ between the sexes in any of the age classes. Information on home range size and use enables specific areas within the species' range to be targeted for management planning, education and conservation action. PMID:25551614

  5. Assessment Of Noise-induced Sleep Fragility In Two Age Ranges By Means Of Polysomnographic Microstructure

    NASA Astrophysics Data System (ADS)

    Terzano, M. G.; Parrino, L.; Spaggiari, M. C.; Buccino, G. P.; Fioriti, G.; Depoortere, H.

    1993-04-01

    The microstructure of sleep, which translates the short-lived fluctuations of the arousal level, is a commonly neglected feature in polysomnographic studies. Specifically arranged microstructural EEG events may provide important information on the dynamic characteristics of the sleep process. CAP (cyclic alternating pattern) and non-CAP are complementary modalities in which arousal-related "phasic" EEG phenomena are organized in non-REM sleep, and they correspond to opposite conditions of unstable and stable sleep depth, respectively. Thus, arousal instability can be measured by the CAP rate, the percentage ratio of total CAP time to total non-REM sleep time. The CAP rate, an age-related physiological variable that increases in several pathological conditions, is highly sensitive to acoustic perturbation. In the present study, two groups of healthy subjects without complaints about sleep, belonging to different age ranges (six young adults, three males and three females, between 20 and 30 years, and six middle-aged individuals, three males and three females, between 40 and 55 years) slept, after adaptation to the sleep laboratory, in a random sequence for two non-consecutive nights either under silent baseline (27·3 dB(A) Lcq) or noise-disturbed (continuous 55 dB(A) white noise) conditions. Age-related and noise-related effects on traditional sleep parameters and on the CAP rate were statistically evaluated by a split-plot test. Compared to young adults, the middle-aged individuals showed a significant reduction of total sleep time, stage 2 and REM sleep and significantly higher values of nocturnal awakenings and the CAP rate. The noisy nights were characterized by similar alterations. The disruptive effects of acoustic perturbation were greater on the more fragile sleep architecture of the older group. The increased fragility of sleep associated with aging probably reflects the decreased capacity of the sleeping brain to maintain steady states of vigilance. Total

  6. A different approach to age range of Neogene sediments in SW Turkey

    NASA Astrophysics Data System (ADS)

    Elitez, İrem; Yaltırak, Cenk

    2015-04-01

    There are different views about the age range of the Neogene rocks at the same locations along Burdur-Fethiye Shear Zone (BFSZ), in SW Turkey. In most of the recent studies, lacustrine limestones, claystones and marls were dated as Pliocene. Besides, meander and braided river conglomerates and sandstones, and also alluvial fan conglomerates, mudstones and claystones were locally mapped together with these lacustrine sediments under the same formation name. Actually, two distinct sedimentary sequences are observed on the region. The first sequence starts at the base with alluvial fan, meander river and braided river sediments of Gölhisar Formation and passes laterally and vertically to lacustrine sediments of İbecik Formation. İbecik Formation is represented by claystone, marl and limestone in all of the basins on BFSZ. The first sequence is unconformably overlain by the second sequence. The second sequence includes alluvial fan conglomerates, mudstones and claystones of Dirmil Formation. When considering the supposed age range of these sediments, the timing of the tectonic evolution of the region cause problems. During our studies on the BFSZ, we observed that this age range (Pliocene) is not acceptable. The lacustrine sediments, which consist mainly of white, whitish yellow, yellow and beige limestone, claystone, marl and fine-grained sandstone, crop out around Eğirdir, Acıgöl, Burdur, Tefenni, Acıpayam, Çameli, Gölhisar and Eşen basins along BFSZ. These sediments are locally cut by the volcanic rocks. Therefore, these volcanic rocks are very important for dating these lacustrine units. Paton (1992) dated the lamproites around Acıpayam at 5.13±0.6, 6.28±0.48, 6.16±0.25 and 6±1.54 Ma (Tortonian-Lower Pliocene). These lamproites cut conglomerates and limestones at around 1300 to 1600 meter elevations. Alçiçek (2001) dated Perrisodactyla-Equidae Hipparion cf. Primigeniup sp. in the clayey limestones (İbecik Fm) as Vallesian. Also, the gypsum and

  7. Theoretical constraints on the precision and age range of rehydroxylation dating

    PubMed Central

    Hare, V. J.

    2015-01-01

    Accurate and precise dating methods are of central importance to archaeology, palaeontology and earth science. This paper investigates the expected precision and age range of rehydroxylation dating, a recently proposed technique for fired clays. An expression for combined measurement uncertainty is presented, which takes into account all significant sources of experimental uncertainty. Numerical simulations are performed for comparison. Combined measurement uncertainties of approximately 5% with respect to the age of the ceramic should be possible given well-designed experiments. In this case, the most significant contribution to combined measurement uncertainty is from effective lifetime temperature. In addition, it is shown that precision should be acceptable for recently fired material (less than 1 year). Mismatch of balance resolution to sample mass results in large variation in combined relative uncertainties, which vary by four orders of magnitude (approx. 1–1160%) across recent experimental studies, rendering some recently reported dates meaningless. It is recommended that this ratio be less than 10−6 for a combined relative uncertainty of less than 1%. The age limits of the technique are set by the value of the rate constant and individual sample mineralogy. This theoretical framework should help future interlaboratory comparison as well as optimizing instrument design. PMID:26064631

  8. Theoretical constraints on the precision and age range of rehydroxylation dating.

    PubMed

    Hare, V J

    2015-04-01

    Accurate and precise dating methods are of central importance to archaeology, palaeontology and earth science. This paper investigates the expected precision and age range of rehydroxylation dating, a recently proposed technique for fired clays. An expression for combined measurement uncertainty is presented, which takes into account all significant sources of experimental uncertainty. Numerical simulations are performed for comparison. Combined measurement uncertainties of approximately 5% with respect to the age of the ceramic should be possible given well-designed experiments. In this case, the most significant contribution to combined measurement uncertainty is from effective lifetime temperature. In addition, it is shown that precision should be acceptable for recently fired material (less than 1 year). Mismatch of balance resolution to sample mass results in large variation in combined relative uncertainties, which vary by four orders of magnitude (approx. 1-1160%) across recent experimental studies, rendering some recently reported dates meaningless. It is recommended that this ratio be less than 10(-6) for a combined relative uncertainty of less than 1%. The age limits of the technique are set by the value of the rate constant and individual sample mineralogy. This theoretical framework should help future interlaboratory comparison as well as optimizing instrument design.

  9. GRAVITY STUDIES IN THE CASCADE RANGE.

    USGS Publications Warehouse

    Finn, Carol; Williams, David

    1983-01-01

    A compatible set of gravity data has been compiled for the entire Cascade Range. From this data set a series of interpretive color gravity maps have been prepared, including a free air anomaly map, Bouguer anomaly map at a principle, and an alternate reduction density, and filtered and derivative versions of the Bouguer anomaly map. The regional anomaly pattern and gradients outline the various geological provinces adjacent to the Cascade Range and delineate major structural elements in the range. The more local anomalies and gradients may delineate low density basin and caldera fill, faults, and shallow plutons. Refs.

  10. Tropospheric range error parameters: Further studies

    NASA Technical Reports Server (NTRS)

    Hopfield, H. S.

    1972-01-01

    Improved parameters are presented for predicting the tropospheric effect on electromagnetic range measurements from surface meteorological data. More geographic locations have been added to the earlier list. Parameters are given for computing the dry component of the zenith radio range effect from surface pressure alone with an rms error of 1 to 2 mm, or the total range effect from the dry and wet components of the surface refractivity and a two-part quartic profile model. The new parameters are obtained, as before, from meteorological balloon data but with improved procedures, including the conversion of the geopotential heights of the balloon data to actual or geometric heights before using the data. The revised values of the parameter k (dry component of vertical radio range effect per unit pressure at the surface) show more latitude variation than is accounted for by the variation of g, the acceleration of gravity.

  11. Tropospheric range error parameters: Further studies

    NASA Technical Reports Server (NTRS)

    Hopfield, H. S.

    1972-01-01

    Improved parameters are presented for predicting the tropospheric effect on electromagnetic range measurements from surface meteorological data. Parameters are given for computing the dry component of the zenith radio range effect from surface pressure alone with an rms error of 1 to 2 mm, or the total range effect from the dry and wet components of the surface refractivity, N, and a two-part quartic profile model. The parameters were obtained from meteorological balloon data with improved procedures, including the conversion of the geopotential heights of the balloon data to actual or geometric heights before using the data. The revised values of the parameter k show more latitude variation than is accounted for by the variation of g. This excess variation of k indicates a small latitude variation in the mean molecular weight of air and yields information about the latitude-varying water vapor content of air.

  12. UXO Discrimination Study Former Spencer Artillery Range

    DTIC Science & Technology

    2013-04-01

    SIG Signal Innovations Group, Inc. SLO San Luis Obispo Demonstration Site Spencer Former Spencer Artillery Range SVD Singular Value Decomposition...include: physics-based target/sensor models, subspace denoising , automated and efficient feature extraction, data selection for classifier training...any scaling in order to be appropriate for the feature extraction software. • Subspace Denoising - The anomaly data is denoised to ensure robust

  13. Age, Stratigraphy, and Correlations of the Late Neogene Purisima Formation, Central California Coast Ranges

    USGS Publications Warehouse

    Powell, Charles L.; Barron, John A.; Sarna-Wojcicki, Andrei M.; Clark, Joseph C.; Perry, Frank A.; Brabb, Earl E.; Fleck, Robert J.

    2007-01-01

    The Purisima Formation is an important upper Miocene and Pliocene stratigraphic unit in central California, cropping out from the coast at Point Reyes north of San Francisco to more extensive exposures in the Santa Cruz Mountains to the south. The fine-grained rocks in the lower parts of the Purisima Formation record a latest Miocene transgressive event, whereas the middle and upper parts of the formation consist of increasingly clastic-rich siltstones and sandstones resulting from uplift of adjacent coastal regions and the Sierra Nevada during Pliocene transgressive and regressive sea-level events. Exposures of the Purisima occur in three different, fault-bounded, structural blocks - the Santa Cruz, Pigeon Point, and Point Reyes tectonic blocks - that complicate correlations and regional age assignments. We summarize and compare published and new biostratigraphic and geochronologic data for various exposures of the Purisima Formation on the basis of mollusks, diatoms, radiometric dating, magnetostratigraphy, tephrochronology, and strontium isotope dating. On the basis of these data, we conclude that the Purisima Formation ranges in age from the latest Miocene (about 7 Ma) to the late Pliocene (about 2.6 Ma). The Purisima Formation of Santa Cruz County, exposed in the sea cliffs from Santa Cruz to Rio del Mar, is here designated a supplementary reference section because it is the most complete and well studied Purisima section in central California.

  14. Depositional settings, correlation, and age carboniferous rocks in the western Brooks Range, Alaska

    USGS Publications Warehouse

    Dumoulin, Julie A.; Harris, Anita G.; Blome, Charles D.; Young, Lorne E.

    2004-01-01

    The Kuna Formation (Lisburne Group) in northwest Alaska hosts the Red Dog and other Zn-Pb-Ag massive sulfide deposits in the Red Dog district. New studies of the sedimentology and paleontology of the Lisburne Group constrain the setting, age, and thermal history of these deposits. In the western and west-central Brooks Range, the Lisburne Group includes both deep- and shallow-water sedimentary facies and local volcanic rocks that are exposed in a series of thrust sheets or allochthons. Deep-water facies in the Red Dog area (i.e., the Kuna Formation and related rocks) are found chiefly in the Endicott Mountains and structurally higher Picnic Creek allochthons. In the Red Dog plate of the Endicott Mountains allochthon, the Kuna consists of at least 122 m of thinly interbedded calcareous shale, calcareous spiculite, and bioclastic supportstone (Kivalina unit) overlain by 30 to 240 m of siliceous shale, mudstone, calcareous radiolarite, and calcareous lithic turbidite (Ikalukrok unit). The Ikalukrok unit in the Red Dog plate hosts all massive sulfide deposits in the area. It is notably carbonaceous, is generally finely laminated, and contains siliceous sponge spicules and radiolarians. The Kuna Formation in the Key Creek plate of the Endicott Mountains allochthon (60–110 m) resembles the Ikalukrok unit but is unmineralized and has thinner carbonate layers that are mainly organic-rich dolostone. Correlative strata in the Picnic Creek allochthon include less shale and mudstone and more carbonate (mostly calcareous spiculite). Conodonts and radiolarians indicate an age range of Osagean to early Chesterian (late Early to Late Mississippian) for the Kuna in the Red Dog area. Sedimentologic, faunal, and geochemical data imply that most of the Kuna formed in slope and basin settings characterized by anoxic or dysoxic bottom water and by local high productivity.

  15. Veterans Aging Cohort Study (VACS)

    PubMed Central

    Justice, Amy C.; Dombrowski, Elizabeth; Conigliaro, Joseph; Fultz, Shawn L.; Gibson, Deborah; Madenwald, Tamra; Goulet, Joseph; Simberkoff, Michael; Butt, Adeel A.; Rimland, David; Rodriguez-Barradas, Maria C.; Gibert, Cynthia L.; Oursler, Kris Ann K.; Brown, Sheldon; Leaf, David A.; Goetz, Matthew B.; Bryant, Kendall

    2010-01-01

    Background The Veterans Aging Cohort Study (VACS) is a study of human immunodeficiency virus (HIV) infected and uninfected patients seen in infectious disease and general medical clinics. VACS includes the earlier 3 and 5 site studies (VACS 3 and VACS 5) as well as the ongoing 8 site study. Objectives We sought to provide background and context for analyses based upon VACS data, including study design and rationale as well as its basic protocol and the baseline characteristics of the enrolled sample. Research Design We undertook a prospectively consented multisite observational study of veterans in care with and without HIV infection. Measures Data were derived from patient and provider self report, telephone interviews, blood and DNA samples, focus groups, and full access to the national VA “paperless” electronic medical record system. Results More than 7200 veterans have been enrolled in at least one of the studies. The 8 site study (VACS) has enrolled 2979 HIV-infected and 3019 HIV-uninfected age–race–site matched comparators and has achieved stratified enrollment targets for race/ethnicity and age and 99% of its total target enrollment as of October 30, 2005. Participants in VACS are similar to other veterans receiving care within the VA. VACS participants are older and more predominantly black than those reported by the Centers for Disease Control. Conclusions VACS has assembled a rich, in-depth, and representative sample of veterans in care with and without HIV infection to conduct longitudinal analyses of questions concerning the association between alcohol use and related comorbid and AIDS-defining conditions. PMID:16849964

  16. Mechanistic studies of photothermal aging

    NASA Technical Reports Server (NTRS)

    Liang, R. H.

    1986-01-01

    Cracks were observed forming in Tedlar back cover films on PV modules mounted outdoors in the natural environment. The cracks appear to approximate reasonable straight lines and, in general, are parallel to each other. It is implied that the directionality of these cracks may be in some way related to film orientation. Preliminary results from the Jet Propulsion Laboratory (JPL) studies investigating the causes of these cracks indicate that Tedlar does not become brittle on aging. It was speculated that perhaps compounding ingredients employed in EVA may migrate into the Tedlar film, thus causing a potential for chemical effects.

  17. Aging studies in Drosophila melanogaster.

    PubMed

    Sun, Yaning; Yolitz, Jason; Wang, Cecilia; Spangler, Edward; Zhan, Ming; Zou, Sige

    2013-01-01

    Drosophila is a genetically tractable system ideal for investigating the mechanisms of aging and developing interventions for promoting healthy aging. Here we describe methods commonly used in Drosophila aging research. These include basic approaches for preparation of diets and measurements of lifespan, food intake, and reproductive output. We also describe some commonly used assays to measure changes in physiological and behavioral functions of Drosophila in aging, such as stress resistance and locomotor activity.

  18. Aging Studies in Drosophila melanogaster

    PubMed Central

    Sun, Yaning; Yolitz, Jason; Wang, Cecilia; Spangler, Edward; Zhan, Ming; Zou, Sige

    2015-01-01

    Summary Drosophila is a genetically tractable system ideal for investigating the mechanisms of aging and developing interventions for promoting healthy aging. Here we describe methods commonly used in Drosophila aging research. These include basic approaches for preparation of diets and measurements of lifespan, food intake and reproductive output. We also describe some commonly used assays to measure changes in physiological and behavioral functions of Drosophila in aging, such as stress resistance and locomotor activity. PMID:23929099

  19. Reduction of Optimal Thermal Range in Aging Western Cherry Fruit Flies (Diptera: Tephritidae).

    PubMed

    Neven, Lisa G

    2015-01-01

    The western cherry fruit fly is an economically important pest of sweet cherries in the western United States. The potential of this pest to establish and spread in areas in which it is not currently present has been the focus of recent research. Most published information on the thermal tolerance and optimal thermal range of this pest has focused primarily on the diapausing pupae and predictive phenology models. Microrespirometry and differential calorimetry can be useful tools in describing the thermotolerance and optimal thermal range of insects. This methodology was employed to investigate the effects of western cherry fruit fly adult age on the optimal thermal range. Newly emerged flies exhibited the widest optimal thermal range spanning from 6.6 to 42.2°C for a total range of 35.8°C during heating scans of 0.4°C/min from 2 to 50°C. This range diminished as the flies aged, with the shortest span observed with 28-d-old flies ranging from 10.5 to 37.8°C, a span of 27.2°C. Measurements of heat rate and oxygen consumption at isothermal, or static, temperatures indicated that all flies could survive exposure to 40°C for at least 20 min, and that metabolism was greatly reduced, with a concomitant reduction in oxygen consumption rate at 40 to 42°C. All flies exhibited a heat rate and oxygen consumption rate of zero when exposed to 45 and 50°C. The loss of thermotolerance in adult flies can influence its ability to establish and spread in climates where daily temperatures exceed the optimal thermal range of this species.

  20. Reduction of Optimal Thermal Range in Aging Western Cherry Fruit Flies (Diptera: Tephritidae)

    PubMed Central

    Neven, Lisa G.

    2015-01-01

    The western cherry fruit fly is an economically important pest of sweet cherries in the western United States. The potential of this pest to establish and spread in areas in which it is not currently present has been the focus of recent research. Most published information on the thermal tolerance and optimal thermal range of this pest has focused primarily on the diapausing pupae and predictive phenology models. Microrespirometry and differential calorimetry can be useful tools in describing the thermotolerance and optimal thermal range of insects. This methodology was employed to investigate the effects of western cherry fruit fly adult age on the optimal thermal range. Newly emerged flies exhibited the widest optimal thermal range spanning from 6.6 to 42.2°C for a total range of 35.8°C during heating scans of 0.4°C/min from 2 to 50°C. This range diminished as the flies aged, with the shortest span observed with 28-d-old flies ranging from 10.5 to 37.8°C, a span of 27.2°C. Measurements of heat rate and oxygen consumption at isothermal, or static, temperatures indicated that all flies could survive exposure to 40°C for at least 20 min, and that metabolism was greatly reduced, with a concomitant reduction in oxygen consumption rate at 40 to 42°C. All flies exhibited a heat rate and oxygen consumption rate of zero when exposed to 45 and 50°C. The loss of thermotolerance in adult flies can influence its ability to establish and spread in climates where daily temperatures exceed the optimal thermal range of this species. PMID:26106089

  1. Middle Jurassic U-Pb crystallization age for Siniktanneyak Mountain ophiolite, Brooks Range, Alaska

    SciTech Connect

    Moore, T.E. ); Aleinikoff, J.N.; Walter, M. )

    1993-04-01

    The authors report here a U-Pb age for the Siniktanneyak Mountain Ophiolite klippe in the west-central Brooks Range, the first U-Pb ophiolite age in northern Alaska. Like klippen of mafic and ultramafic rocks in the Brooks Range, the Siniktanneyak Mountain klippe is composed of a lower allochthon of Devonian and younger( ) diabase and metabasalt with trace-element characteristics of seamount basalts and an upper allochthon of ophiolite. The ophiolite is partial, consisting of (1) abundant dunite and subordinate harzburgite and wehrlite; (2) cumulate clinopyroxene gabbro, and (3) minor noncumulate clinopyroxene gabbro and subordinate plagiogranite; no sheeted dikes or volcanic rocks are known in the ophilitic allochthon. The plagiogranite forms small dikes and stocks that intrude the noncumulate gabbro and consists of zoned Na-rich plagioclase + clinopyroxene with interstial quartz and biotite. Five fractions of subhedral, tan zircon from the plagiogranite yield slightly discordant U-Pb data with an upper intercept age of 170 [+-] 3 Ma. The U-Pb data indicate that the Siniktanneyak Mountain ophiolite crystallized in the Middle Jurassic and was emplaced by thrusting onto mafic accretionary prism rocks within about 10 m.y. of crystallization. The U-Pb data provide an upper limit to the age of initiation of the Brookian orogeny.

  2. Isotopic complexities and the age of the Delfonte volcanic rocks, eastern Mescal Range, southeastern California: Stratigraphic and tectonic implications

    USGS Publications Warehouse

    Fleck, R.J.; Mattinson, J.M.; Busby, C.J.; Carr, M.D.; Davis, G.A.; Burchfiel, B.C.

    1994-01-01

    Combined U-Pb zircon, Rb-Sr, 40Ar/39Ar laser-fusion, and conventional K-Ar geochronology establish a late Early Cretaceous age for the Delfonte volcanic rocks. U-Pb zircon analyses define a lower intercept age of 100.5 ± 2 Ma that is interpreted as the crystallization age of the Delfonte sequence. Argon studies document both xenocrystic contamination and postemplacement Ar loss. Rb-Sr results from mafic lavas at the base of the sequence demonstrate compositionally correlated variations in initial 87Sr/86Sr ratios (Sri) from 0.706 for basalts to 0.716 for andesitic compositions. This covariation indicates substantial mixing of subcontinental lithosphere with Proterozoic upper crust. Correlations between Rb/Sr and Sri may result not only in pseudoisochrons approaching the age of the crustal component, but also in reasonable but incorrect apparent ages approaching the true age.Ages obtained in this study require that at least some of the thrust faulting in the Mescal Range-Clark Mountain portion of the foreland fold-and-thrust belt occurred later than ca. 100 Ma and was broadly contemporaneous with emplacement of the Keystone thrust plate in the Spring Mountains to the northeast. Comparison of the age and Rb-Sr systematics of ash-flow tuff boulders in the synorogenic Lavinia Wash sequence near Goodsprings, Nevada, with those of the Delfonte volcanic rocks supports a Delfonte source for the boulders. The 99 Ma age of the Lavinia Wash sequence is nearly identical to the Delfonte age, requiring rapid erosion, transport, and deposition following Delfonte volcanism.

  3. Glacier retreat since the Little Ice Age in the eastern Nyainqêntanglha Range, southeastern Tibet

    NASA Astrophysics Data System (ADS)

    Loibl, David; Grießinger, Jussi; Lehmkuhl, Frank

    2014-05-01

    The remote eastern Nyainqêntanglha Range in southeastern Tibet is situated in a transition zone between warm-wet subtropical and cold-dry plateau climate conditions. In this high mountain environment, intense summer monsoon rainfalls support numerous temperate glaciers despite the latitude of ~29° to ~31°N. Due to the outstanding importance of the monsoonal airmasses for the water cycle of the whole region, it is a key area to study climate and subsequent glacier change in High Asia. Here, we present the results of a study in which 1964 glaciers were mapped by remote sensing from a Landsat ETM+ scene and subsequently parameterized by DEM supported measurements. Geomorphological evidence, such as glacier trimlines and latero-frontal moraines, was used to delineate the Little Ice Age (LIA) maximum glacier advance terminus positions. Statistical analysis of glacier length change revealed an average retreat of ~40 % and a trend towards stronger retreat for smaller glaciers. Calculated ELAs show a southeast-northwest gradient ranging from 4,400 to 5,600 m a.s.l. and an average ELA rise of ~98 m since the LIA. Due to the large amount of measurements the ELA distribution reveals topographic effects down to the catchment scale, i.e. orographic rainfall and leeward shielding. This gives numerous hints on the relief-climate-glacier interactions and allows a simplified reconstruction of the flow patterns of the monsoonal air masses. Contrasting to the expectations for subtropical settings, glaciers on south facing slopes have not retreated strongest and ELAs on south facing slopes did not rise furthest. Instead, highly heterogeneous spatial patterns emerge that show a strong imprint of both, topography and monsoonal dynamics. Our results indicate that the monsoonal temperate glaciers' high sensitivity to climate change is driven by two double forcings due to the coincidence of accumulation and ablation phases. First, monsoon intensity directly controls the amount of

  4. Zircon fission-track ages from the Gasherbrum Diorite, Karakoram Range, northern Pakistan

    SciTech Connect

    Cerveny, P.F. ); Naeser, C.W. ); Kelemen, P.B. ); Lieberman, J.E. ); Zeitler, P.K. )

    1989-11-01

    The Gasherbrum Peaks, in the Himalaya of Pakistan, reach elevations of >8000 m. The relief between the peaks and the adjacent valley (Baltoro Glacier) is in excess of 3000 m. Eight samples of the Early Cretaceous Gasherbrum Diorite at elevations between 4880 and 7165 m on Gasherbrum IV were collected for fission-track dating. Zircon fission-track ages from the Gasherbrum Diorite vary from Early Cretaceous to middle Tertiary in age. There is no consistent pattern between age and elevation. The Cretaceous ages indicate that these rocks were never deeply buried, i.e., heated to temperatures in excess of 175 C, to reset the zircons during Cenozoic time. These results also indicate that the uplift of this part of the Himalaya has been either very rapid and recent, or very slow since Early Cretaceous time. This latter possibility is not consistent with the high relief at Gasherbrum and what is known about regional tectonics. Gasherbrum IV zircons, currently at {approximately}4880 m, have never been at depths greater than 6 km, and less than 3 km of material has been removed from the top of the range by erosion since the Early Cretaceous. Rapid uplift has occurred very recently, and erosion rates have not been able to keep pace with this uplift.

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

    PubMed

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

    2016-02-01

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

  6. [Cognitive capacity in advanced age: initial results of the Berlin Aging Study].

    PubMed

    Lindenberger, U; Baltes, P B

    1995-01-01

    This study reports data on intellectual functioning in old and very old age from the Berlin Aging Study (N = 516; age range = 70-103 years; mean age = 85 years). A psychometric battery of 14 tests was used to assess five cognitive abilities: reasoning, memory, and perceptual speed from the broad fluid-mechanical as well as knowledge and fluency from the broad crystallized-pragmatic domains. Cognitive abilities had a negative linear relationship with age, with more pronounced age-based reductions in fluid-mechanical than crystallized-pragmatic abilities. At the same time, ability intercorrelations formed a highly positive manifold, and did not follow the fluid-crystallized distinction. Interindividual variability was of about equal magnitude across the entire age range studied. There was, however, no evidence for substantial sex differences. As to origins of individual differences, indicators of sensory and sensorimotor functioning were more powerful predictors of intellectual functioning than cultural-biographical variables, and the two sets of predictors were, consistent with theoretical expectations, differentially related to measures of fluid-mechanical (perceptual speed) and crystallized pragmatic (knowledge) functioning. Results, in general indicative of sizeable and general losses with age, are consistent with the view that aging-induced biological influences are a prominent source of individual differences in intellectual functioning in old and very old age. Longitudinal follow-ups are underway to examine the role of cohort effects, selective mortality, and interindividual differences in change trajectories.

  7. Study on evaluation of photoelectric jamming effectiveness on ranging lidar

    NASA Astrophysics Data System (ADS)

    Che, Jinxi; Yang, Haiqiang; Gao, Bo

    2015-11-01

    Lidar (Light Detection and Range) is a brand-new field and research hotspot. Ranging lidar is studied in this paper. Specifically, its basic working principle and photoelectric jamming mechanism are introduced. Then, the ranging error jamming success rate rule is developed for laser distance deception jamming. And the effectiveness evaluation of laser blinding jamming is based on the influence level on ranging accuracy and ranging function. The results have some reference value to evaluation of jamming test effectiveness.

  8. Age constraints for Paleoproterozoic glaciation in the Lake Superior Region: Detrital zircon and hydrothermal xenotime ages for the Chocolay Group, Marquette Range Supergroup

    USGS Publications Warehouse

    Vallini, D.A.; Cannon, W.F.; Schulz, K.J.

    2006-01-01

    A geochronological study of the Chocolay Group at the base of the Paleoproterozoic Marquette Range Supergroup in Michigan, Lake Superior Region, is attempted for the first time, Age data from detrital zircon grains and hydrothermal xenotime from the basal glaciogenic formation, the Enchantment Lake Formation, and the stratigraphically higher Sturgeon Quartzite and its equivalent, the Sunday Quartzite, provide maximum and minimum age constraints for the Chocolay Group. The youngest detrital zircon population in the Enchantment Lake Formation is 2317 ?? 6 Ma; in the Sturgeon Quartzite, it is 2306 ?? 9 Ma, and in the Sunday Quartzite, it is 2647 ?? 5 Ma. The oldest hydrothermal xenotime age in the Enchantment Lake Formation is 2133 ?? 11 Ma; in the Sturgeon Quartzite, it is 2115 ?? 5 Ma, and in the Sunday Quartzite, it is 2207 ?? 5 Ma. The radiometric age data in this study implies the depositional age of the Chocolay Group is constrained to ???2.3-2.2 Ga, which proves its correlation with part of the Huronian Supergroup in the Lake Huron Region, Ontario, and reveals the unconformity that separates the Chocolay Group from the overlying Menominee Group is up to 325 million years in duration. The source(s) of the ??? 2.3 Ga detrital zircon populations in the Enchantment Lake Formation and Sturgeon Quartzite remains an enigma because no known rock units of this age are known in the Michigan area. It is speculated that once widespread volcano-sedimentary cover sequences in Michigan were removed or concealed prior to Chocolay Group deposition. The hydrothermal xenotime ages probably reflect basinal hydrothermal fluid flow associated with the period of extension involving rifting and major dyke formation, that affected the North American provinces between 2.2 and 2.1 Ga. ?? 2006 NRC Canada.

  9. Childlessness and Psychological Well-Being in Midlife and Old Age: An Examination of Parental Status Effects across a Range of Outcomes

    ERIC Educational Resources Information Center

    Hansen, Thomas; Slagsvold, Britt; Moum, Torbjorn

    2009-01-01

    The study explores and distinguishes links between parental status (childless persons, parents with residential children, and empty nest parents) and a range of psychological well-being outcomes in midlife and old age. Data are from the first wave of the Norwegian Life Course, Ageing and Generation (NorLAG) study (n = 5,189). We separate outcomes…

  10. Does age matter? The impact of rodent age on study outcomes.

    PubMed

    Jackson, Samuel J; Andrews, Nick; Ball, Doug; Bellantuono, Ilaria; Gray, James; Hachoumi, Lamia; Holmes, Alan; Latcham, Judy; Petrie, Anja; Potter, Paul; Rice, Andrew; Ritchie, Alison; Stewart, Michelle; Strepka, Carol; Yeoman, Mark; Chapman, Kathryn

    2017-04-01

    Rodent models produce data which underpin biomedical research and non-clinical drug trials, but translation from rodents into successful clinical outcomes is often lacking. There is a growing body of evidence showing that improving experimental design is key to improving the predictive nature of rodent studies and reducing the number of animals used in research. Age, one important factor in experimental design, is often poorly reported and can be overlooked. The authors conducted a survey to assess the age used for a range of models, and the reasoning for age choice. From 297 respondents providing 611 responses, researchers reported using rodents most often in the 6-20 week age range regardless of the biology being studied. The age referred to as 'adult' by respondents varied between six and 20 weeks. Practical reasons for the choice of rodent age were frequently given, with increased cost associated with using older animals and maintenance of historical data comparability being two important limiting factors. These results highlight that choice of age is inconsistent across the research community and often not based on the development or cellular ageing of the system being studied. This could potentially result in decreased scientific validity and increased experimental variability. In some cases the use of older animals may be beneficial. Increased scientific rigour in the choice of the age of rodent may increase the translation of rodent models to humans.

  11. Does age matter? The impact of rodent age on study outcomes

    PubMed Central

    Andrews, Nick; Ball, Doug; Bellantuono, Ilaria; Gray, James; Hachoumi, Lamia; Holmes, Alan; Latcham, Judy; Petrie, Anja; Potter, Paul; Rice, Andrew; Ritchie, Alison; Stewart, Michelle; Strepka, Carol; Yeoman, Mark; Chapman, Kathryn

    2016-01-01

    Rodent models produce data which underpin biomedical research and non-clinical drug trials, but translation from rodents into successful clinical outcomes is often lacking. There is a growing body of evidence showing that improving experimental design is key to improving the predictive nature of rodent studies and reducing the number of animals used in research. Age, one important factor in experimental design, is often poorly reported and can be overlooked. The authors conducted a survey to assess the age used for a range of models, and the reasoning for age choice. From 297 respondents providing 611 responses, researchers reported using rodents most often in the 6–20 week age range regardless of the biology being studied. The age referred to as ‘adult’ by respondents varied between six and 20 weeks. Practical reasons for the choice of rodent age were frequently given, with increased cost associated with using older animals and maintenance of historical data comparability being two important limiting factors. These results highlight that choice of age is inconsistent across the research community and often not based on the development or cellular ageing of the system being studied. This could potentially result in decreased scientific validity and increased experimental variability. In some cases the use of older animals may be beneficial. Increased scientific rigour in the choice of the age of rodent may increase the translation of rodent models to humans. PMID:27307423

  12. Surface-exposure ages of Front Range moraines that may have formed during the Younger Dryas, 8.2 cal ka, and Little Ice Age events

    USGS Publications Warehouse

    Benson, L.; Madole, R.; Kubik, P.; McDonald, R.

    2007-01-01

    Surface-exposure (10Be) ages have been obtained on boulders from three post-Pinedale end-moraine complexes in the Front Range, Colorado. Boulder rounding appears related to the cirque-to-moraine transport distance at each site with subrounded boulders being typical of the 2-km-long Chicago Lakes Glacier, subangular boulders being typical of the 1-km-long Butler Gulch Glacier, and angular boulders being typical of the few-hundred-m-long Isabelle Glacier. Surface-exposure ages of angular boulders from the Isabelle Glacier moraine, which formed during the Little Ice Age (LIA) according to previous lichenometric dating, indicate cosmogenic inheritance values ranging from 0 to ???3.0 10Be ka.11Surface-exposure ages in this paper are labeled 10Be; radiocarbon ages are labeled 14C ka, calendar and calibrated radiocarbon ages are labeled cal ka, and layer-based ice-core ages are labeled ka. 14C ages, calibrated 14C ages, and ice core ages are given relative to AD 1950, whereas 10Be ages are given relative to the sampling date. Radiocarbon ages were calibrated using CALIB 5.01 and the INTCAL04 data base Stuiver et al. (2005). Ages estimated using CALIB 5.01 are shown in terms of their 1-sigma range. Subangular boulders from the Butler Gulch end moraine yielded surface-exposure ages ranging from 5 to 10.2 10Be ka. We suggest that this moraine was deposited during the 8.2 cal ka event, which has been associated with outburst floods from Lake Agassiz and Lake Ojibway, and that the large age range associated with the Butler Gulch end moraine is caused by cosmogenic shielding of and(or) spalling from boulders that have ages in the younger part of the range and by cosmogenic inheritance in boulders that have ages in the older part of the range. The surface-exposure ages of eight of nine subrounded boulders from the Chicago Lakes area fall within the 13.0-11.7 10Be ka age range, and appear to have been deposited during the Younger Dryas interval. The general lack of inheritance in

  13. Map, tables, and summary of fossil and isotopic age data, Mount Hayes Quadrangle, eastern Alaska range, Alaska

    USGS Publications Warehouse

    Nokleberg, Warren J.; Aleinikoff, John N.; Dutro, J. Thomas; Lanphere, Marvin A.; Silberling, Norman J.; Silva, Steven R.; Smith, Thomas E.; Turner, Donald L.

    1992-01-01

    This report describes, summarizes, and interprets all known bedrock fossil and isotopic age studies for the Mount Hayes quadrangle, eastern Alaska Range, Alaska. The accompanying map shows the location of all known bedrock fossil and isotopic sample localities in the quadrangle on a generalized geologic base map. These fossil and isotopic age data are obtained from new studies, unpublished data of the U.S. Geological Survey, contributed unpublished data, and published data. This report is one result of a five-year mineral resource assessment of the quadrangle that was done during the summers of 1978 through 1982, with additional topical studiesin 1985 and 1986. This report is one part of a folio on the geological, geochemical, geophysical, and mineral-resource assessment studies of the quadrangle prepared as part of the Alaskan Mineral Resource Assessment Program (AMRAP) of the U.S. Geological Survey.

  14. [Deafness and aging: studies in experimental models].

    PubMed

    Gil Loyzaga, Pablo E

    2002-01-01

    Since 1970 a progressive aging of the world population, mainly in the most developed countries, has been observed. Spain could have, around 2050, the most aged human population of the world. Therefore, scientist show an increasing interest on the study of the aging-related pathologies (i.e. deafness linked to aging process: presbycusis). The deep analysis of the presbycusis physiopathology will be based on the study of patients, but also on animal models. This report summarizes our results obtained on the analysis of the deafness linked to aging on the C57/BL/6 mice.

  15. Age, but not anthelmintic treatment, is associated with urinary neopterin levels in semi-free ranging Barbary macaques

    PubMed Central

    Müller, Nadine; Heistermann, Michael; Strube, Christina; Schülke, Oliver; Ostner, Julia

    2017-01-01

    Studying host parasite interactions and their implications for evolution and ecology recently received increasing attention, particularly with regard to host physiology and immunity. Here we assess variation of urinary neopterin (uNEO), a marker of cellular immune activation and iummunosenescence, in response to age and anthelmintic treatment in semi-free ranging Barbary macaques (Macaca sylvanus). Urinary NEO levels were measured via enzyme-immunoassay from 179 urine samples of 43 individuals between 5–29 years of age. Efficiency of treatment was assessed by Mc Master flotation on repeated faecal samples, including 18 untreated individuals as control group. We used linear mixed models with age and parasite status as main effects, controlling for sex and physical condition, assessed through urinary C-Peptide-levels, with social group and ID as random factors. Urinary NEO levels significantly increased with age, suggesting that changes in aging Barbary macaque immune responses are consistent with immunosenescence described in human and nonhuman primates and can be detected via uNEO measurements. Anthelmintic treatment, however, had no influence on uNEO levels, potentially due to quick reinfections or attenuated immune responses in repeated infections. We conclude that uNEO is a potential non-invasive marker for immune function and particularly immunosenescence in wildlife. PMID:28155915

  16. Impact of specific training and competition on myocardial structure and function in different age ranges of male handball players.

    PubMed

    Agrebi, Brahim; Tkatchuk, Vladimir; Hlila, Nawel; Mouelhi, Emna; Belhani, Ali

    2015-01-01

    Handball activity involves cardiac changes and demands a mixture of both eccentric and concentric remodeling within the heart. This study seeks to explore heart performance and cardiac remodeling likely to define cardiac parameters which influence specific performance in male handball players across different age ranges. Forty three players, with a regular training and competitive background in handball separated into three groups aged on average 11.78 ± 0.41 for youth players aka "schools", "elite juniors" 15.99 ± 0.81 and "elite adults" 24.46 ± 2.63 years, underwent echocardiography and ECG examinations. Incremental ergocycle and specific field (SFT) tests have also been conducted. With age and regular training and competition, myocardial remodeling in different age ranges exhibit significant differences in dilatation's parameters between "schools" and "juniors" players, such as the end-diastolic diameter (LVEDD) and the end-systolic diameter of the left ventricle (LVESD), the root of aorta (Ao) and left atrial (LA), while significant increase is observed between "juniors" and "adults" players in the interventricular septum (IVS), the posterior wall thicknesses (PWT) and LV mass index. ECG changes are also noted but NS differences were observed in studied parameters. For incremental maximal test, players demonstrate a significant increase in duration and total work between "schools" and "juniors" and, in total work only, between "juniors" and "seniors". The SFT shows improvement in performance which ranged between 26.17 ± 1.83 sec to 31.23 ± 2.34 sec respectively from "seniors" to "schools". The cross-sectional approach used to compare groups with prior hypothesis that there would be differences in exercise performance and cardiac parameters depending on duration of prior handball practice, leads to point out the early cardiac remodeling within the heart as adaptive change. Prevalence of cardiac chamber dilation with less hypertrophy remodeling was found

  17. Constraining Metallicity and Age for Massive Quiescent Galaxies in a Redshift Range of 1

    NASA Astrophysics Data System (ADS)

    Estrada-Carpenter, Vicente; Papovich, Casey J.; Momcheva, Ivelina G.; Brammer, Gabriel; Bridge, Joanna; Dickinson, Mark; Closson Ferguson, Henry; finlator, kristian; Finkelstein, Steven L.; Giavalisco, Mauro; Gosmeyer, Catherine; Livermore, Rachael C.; Long, James; Lotz, Jennifer M.; Kawinwanichakij, Lalitwadee; Pirzkal, Norbert; Quadri, Ryan; Salmon, Brett W.; Tilvi, Vithal; Trump, Jonathan R.; Weiner, Benjamin J.

    2017-01-01

    Using HST/WFC3 grism spectroscopy from the CANDELS Lyman-alpha Emission at Reionization (CLEAR) survey, we constrain the metallicities and ages of massive quiescent galaxies, at z ~ 1.5. CLEAR provides deep spectroscopy (12 HST orbits per pointing) with the WFC3/G102 grism over the wavelength range ~ 7,500 < λ < 12,000 Å, at a spectral resolution of R ~ 200, within the GOODS-N and GOODS-S Deep regions of CANDELS. These data cover important age and metallicity sensitive spectral features for galaxies at 1 < z < 2, including the redshifted Ca HK lines, 4000 Å break, Balmer-series lines, and Hg+G features. We stack the G102 spectra of a stellar-mass limited sample of 34 quiescent galaxies, with log(M*/M⊙) > 10 and 1 < z < 2, and fit the spectra using two sets of stellar population synthesis models, BC03 (Bruzual & Charlot 2003) and FSPS (Flexible Stellar Population Synthesis, Conroy & Gunn 2010). From these fits, we construct probability distribution functions of age and metallicity for these galaxies, separated into two mass bins, 10 < log(M*/M⊙) < 10.9 and log(M*/M⊙) > 10.9. The model fits favor higher metallicity for the more massive quiescent galaxies, with Z/Z⊙ ~ 1, with some systematics possibly leading from differences in the stellar population models. Therefore, there is no evidence for significant evolution in metallicity for the most massive quiescent galaxies since z ~ 1.5. The model fits to the lower mass quiescent galaxies favor lower metallicites, Z/Z⊙ ~ 0.4, with an offset of ~ 0.3 dex from the present-day relation (e.g., Galazzi et al. 2005). For quiescent galaxies in this mass range, 10.0 < log(M*/M⊙) < 10.9, this requires evolution in metallicity, either as a result of continued chemical enrichment of current galaxies, or the formation of additional quiescent galaxies (presumably quenching of star-forming galaxies at z > 1), or a combination of the two.

  18. The prevalence of Campylobacter amongst a free-range broiler breeder flock was primarily affected by flock age.

    PubMed

    Colles, Frances M; McCarthy, Noel D; Layton, Ruth; Maiden, Martin C J

    2011-01-01

    Campylobacter successfully colonizes broiler chickens, but little is known about the longer term natural history of colonization, since most flocks are slaughtered at an immature age. In this study, the prevalence and genetic diversity of Campylobacter colonizing a single free-range broiler breeder flock was investigated over the course of a year. The age of the flock was the most important factor in determining both the prevalence and diversity of Campylobacter over time. There was no correlation with season, temperature, the amount of rain and sunshine, or the dynamics of colonization amongst geographically and temporally matched broiler flocks. The higher prevalence rates coincided with the age at which broiler chickens are typically slaughtered, but then in the absence of bio-security or other intervention methods, and despite changes in flock management, the prevalence fell to significantly lower levels for the remainder of the study. The genetic diversity of Campylobacter increased as the flock aged, implying that genotypes were accumulated within the flock and may persist for a long time. A better understanding of the ecology of Campylobacter within commercial chicken flocks will allow the design of more effective farm-based interventions.

  19. Age and Fertility: A Study on Patient Awareness

    PubMed Central

    Deatsman, Sara; Vasilopoulos, Terrie; Rhoton-Vlasak, Alice

    2016-01-01

    Objective Fertility declines as women age. Advancing maternal age increases pregnancy risks such as diabetes or hypertension. Studies suggest women are not aware of the risks of aging on fertility and pregnancy. The study objective was to assess women's knowledge of fertility and reproductive outcomes affected by aging. Methods Prospective IRB approved survey of women (n=94) attending an obstetrics and gynecology (OB/GYN) clinic. Data collected included demographics, pregnancy history, and knowledge of age-related fertility decline and pregnancy risks. Statistical analysis performed using JMP Pro11.0. Results Ages ranged from 18 to 67. One third (30.5%) were aware fertility begins to decline at age 35, however this varied among groups depending on prior history of infertility or requiring fertility treatment. Nulliparous women were more unaware of the health risks of pregnancy over age 35 (1.4% vs 13.6%, P 0.02). African Americans (AA) women were less likely to think obesity (76% Caucasian vs 47.8% AA vs 66.7% other, P < 0.05) and older age (88% Caucasian vs 60.9% AA vs 82.7% other, P 0.02) affected fertility. Conclusion Knowledge regarding fertility and reproduction related to aging was variable and differed by age and race. Difficulty conceiving appears to be associated with higher knowledge levels. Public education will increase awareness of age-related fertility declines. Increased contact during pregnancy is an excellent opportunity to educate women in a nondirective way. PMID:27584600

  20. Thermoluminescence dating of sediments: a re-extension of age range for loess

    SciTech Connect

    Johnson, R.J.; Stipp, J.J.; Wintle, A.G.; Tamers, M.A.

    1985-01-01

    Thermoluminescence (TL) dating of wind blown minerals provides a technique whereby non-carbonaceous sediments could be dated to several hundred thousand years. Two recent reports, however, indicate age underestimates on feldspar in some European loesses older than 50 ka, the effect increasing in severity with age. Suggested causes include decay of luminescence centers, or does dependent sensitivity changes. Data presented in this paper do not support these limitations or explanations. TL provides 3 separate techniques of dating sediments, which, when used together, prove to be efficient internal cross checks for mineralogical anomalies or inconsistencies created by any of the individual methods. In the authors studies each sample was dated by all 3 methods whereas the Europeans analyses employed only the Regeneration technique. This work presents results from loess sections in Mississippi, Illinois and Alaska. These show excellent internal consistency, and consistency with both independent dating methods and stratigraphy, with 2 exceptions. Both exceptions were by the Regen technique giving age underestimates up to 30%. The underestimates were found to be caused by a change in mineral sensitivity resulting from the Regen requirements of strong laboratory light-bleaching followed by irradiations. A simple method to test and correct for this condition is presented. TL thus appears to remain a powerful and increasingly flexible method of sediment dating.

  1. Isotopes and ages in the northern Peninsular Ranges batholith, southern California

    USGS Publications Warehouse

    Kistler, Ronald W.; Wooden, Joseph L.; Morton, Douglas M.

    2003-01-01

    Strontium, oxygen and lead isotopic and rubidium-strontium geochronologic studies have been completed on Cretaceous and Jurassic (?) granitic rock samples from the northern Peninsular Ranges batholith in southern California. Many of these samples were collected systematically and studied chemically by A. K. Baird and colleagues (Baird and others, 1979). The distribution of these granitic rocks is shown in the Santa Ana, Perris, and San Jacinto Blocks, bounded by the Malibu Coast-Cucamonga, Banning, and San Andreas fault zones, and the Pacific Ocean on the map of the Peninsular Ranges batholith and surrounding area, southern California. The granitic rock names are by Baird and Miesch (1984) who used a modal mineral classification that Bateman and others (1963) used for granitic rocks in the Sierra Nevada batholith. In this classification, granitic rocks have at least 10% quartz. Boundaries between rock types are in terms of the ratio of alkali-feldspar to total feldspar: quartz diorite, 0-10%; granodiorite, 10-35%; quartz monzonite 35-65%; granite >65%. Gabbros have 0-10% quartz. Data for samples investigated are giv in three tables: samples, longitude, latitude, specific gravity and rock type (Table 1); rubidium and strontium data for granitic rocks of the northern Peninsular Ranges batholith, southern California (Table 2); U, Th, Pb concentrations, Pb and Sr initial isotopic compositions, and δ18O permil values for granitic rocks of the northern Peninsular Ranges batholith (table 3).

  2. Age range of formation of sedimentary-volcanogenic complex of the Vetreny Belt (the southeast of the Baltic Shield)

    NASA Astrophysics Data System (ADS)

    Mezhelovskaya, S. V.; Korsakov, A. K.; Mezhelovskii, A. D.; Bibikova, E. V.

    2016-03-01

    As a result of studying the Vetreny Belt greenstone structure (the southeast of the Baltic Shield), zircons from terrigenous deposits of the Toksha Formation, underlying the section of the sedimentary-volcanogenic complex, and zircons of the Vetreny Belt Formation, deposits of which crown the section, were dated. The results of analysis of age data of detrital zircons from quartzites of the Toksha Formation indicate that Mesoarchean greenstone complexes and paleo-Archean granitogneisses of the Vodlozero Block (Karelia) were the provenance area from which these zircons were derived. The occurrence of the youngest zircons with age of 2654.3 ± 38.5 Ma is evidence that the formation of the Vetreny Belt, including the Toksha Formation, began no earlier than this time. Zircons from volcanic rocks of the Vetreny Belt yielded the age of 2405 ± 5 Ma. Thus, the age interval of the formation of the sedimentary-volcanogenic complex of the Vetreny Belt ranges from 2654.3 ± 38.5 to 2405 ± 5 Ma.

  3. Plutonic rocks of Jurassic age in the Alaska-Aleutian Range batholith: chemical variation and polarity.

    USGS Publications Warehouse

    Reed, B.I.; Miesch, A.T.; Lanphere, M.A.

    1983-01-01

    Plutonic rocks of Jurassic age exposed on the Pacific side of this batholith form a compositionally continuous calc-alkaline suite that ranges from hornblende gabbro to quartz monzonite. Tonalite and quartz diorite are the dominant rock types. Trend-surface analysis of 102 samples indicates that the direction of slope of the trend is approximately normal to the Jurassic magmatic arc. K2O and SiO2 increase towards the E-SE and the other oxides towards the W-NW. If the chemical trends reflect the approximate geometry of a palaeo-subduction zone, the polarity of the Jurassic magmatic arc is to the NW, i.e. subduction was directed towards the SE. Thus the palaeo-subduction zone is on the opposite side of the arc from the position that has generally been assumed, indicating that the Jurassic plutonic rocks were not generated in response to classical Andean-type convergent plate margins. The magmatic arc may have been formed in an intra-ocean environment and subsequently has been rafted northwards and accreted to this part of the N Pacific rim during the late Mesozoic. Middle and Upper Jurassic clastics underlying Cook Inlet to the SE and derived from the magmatic arc are classified as back-arc deposits, rather than as an arc-trench gap sequence.-L.C.H.

  4. Education in Old Age: An Exploratory Study

    ERIC Educational Resources Information Center

    Luppi, Elena

    2009-01-01

    The following work outlines an analysis of education initiatives aimed at the elderly. It examines the characteristics of the old aged learner, his/her "educability" and the foundations for an educational approach for this age group. These theoretical assumptions form the basis of this research: an exploratory study into various…

  5. An Experimental Study on Registration Three-Dimensional Range Images Using Range and Intensity Data

    NASA Astrophysics Data System (ADS)

    Altuntas, C.

    2011-04-01

    Laser scanner is noncontact instrument to measurement of spatial data. It measures object surfaces as point series and visualize as point cloud. One of the important steps on processes of laser scanning data is the registration of point clouds relation to common coordinate system. Many interactive and automatic methods have been developed for point cloud registration so far. The automatic methods are applied with range data of laser scanner or image data of sensor combination camera. The registration by range data is mostly depend object geometry. If scan surface is deprived from geometrical details, conjugate points can not be found to compute registration parameters between point clouds. In that case, intensity data of laser points can be used for registration. In this study, intensity image was created from laser scanner data and the registration parameters were computed with keypoints extracted by SIFT method from these images. The results were also compared with the iterative closest point (ICP) method.

  6. New U/Pb ages from granite and granite gneiss in the Ruby geanticline and southern Brooks Range, Alaska ( USA).

    USGS Publications Warehouse

    Patton, W.W.; Stern, T.W.; Arth, Joseph G.; Carlson, C.

    1987-01-01

    New U/Pb zircon ages from the Ray Mountains of central Alaska clarify the plutonic history of the Ruby geanticline and support earlier suggestions that the Ruby geanticline and S Brooks Range were once parts of the same tectonostratigraphic terrane. U/Pb zircon ages of 109 to 112 Ma from the Ray Mountains pluton confirm previously reported mid-Cretaceous K/Ar ages and rule out the possibility that the earliest intrusive phase of the pluton is older than mid-Cretaceous K/Ar ages and rule out the possibility that the earliest intrusive phase of the pluton is older than mid- Cretaceous. New U/Pb zircon ages from 4 granite gneiss samples in the Ray Mountains indicate a Devonian protolith age of 390+ or -12 Ma and suggest that the Ruby geanticline, like the S Brooks Range, underwent a major plutonic event in mid-Paleozoic time.-Authors

  7. A semi-automated pipeline for the segmentation of rhesus macaque hippocampus: validation across a wide age range.

    PubMed

    Hunsaker, Michael R; Amaral, David G

    2014-01-01

    This report outlines a neuroimaging pipeline that allows a robust, high-throughput, semi-automated, template-based protocol for segmenting the hippocampus in rhesus macaque (Macaca mulatta) monkeys ranging from 1 week to 260 weeks of age. The semiautomated component of this approach minimizes user effort while concurrently maximizing the benefit of human expertise by requiring as few as 10 landmarks to be placed on images of each hippocampus to guide registration. Any systematic errors in the normalization process are corrected using a machine-learning algorithm that has been trained by comparing manual and automated segmentations to identify systematic errors. These methods result in high spatial overlap and reliability when compared with the results of manual tracing protocols. They also dramatically reduce the time to acquire data, an important consideration in large-scale neuroradiological studies involving hundreds of MRI scans. Importantly, other than the initial generation of the unbiased template, this approach requires only modest neuroanatomical training. It has been validated for high-throughput studies of rhesus macaque hippocampal anatomy across a broad age range.

  8. Dynamic range studies and improvements for multiplexed photonic Doppler velocimetry

    NASA Astrophysics Data System (ADS)

    Miller, Edward Kirk; Lee, Kevin; Larson, Eric; Daykin, Edward

    2017-01-01

    We present studies of the dynamic range achievable with multiplexed photonic Doppler velocimetry (MPDV) measurements, and we demonstrate some techniques to extend the dynamic range. Improved dynamic range for MPDV measurements is needed in order to track the velocity of the free surface behind a cloud of ejecta, so we have undertaken theoretical and experimental studies of factors affecting dynamic range, particularly in cases where the large number of MPDV probe points precludes high illumination power on each channel. To quantify the potential dynamic range of a given MPDV configuration, we introduce a metric called the frequency-domain number of bits, FNOB, which is less stringent than the formally defined equivalent number of bits (ENOB). This new metric is simple to compute in the lab, and it is well suited to conventional PDV analysis, which does not require digitizer phase coherence beyond tens of nanoseconds.

  9. Pliocene Cosmogenic Nuclide Burial Ages of the Nenana Gravel: Progress in Dating and Implications for Alaska Range Evolution

    NASA Astrophysics Data System (ADS)

    Goehring, B. M.; Bemis, S. P.; Ward, D.; Caffee, M. W.; Sortor, R. N.

    2015-12-01

    The Nenana Gravel is an up to 1.2 km thick foreland basin deposit that spans the north flank of the Alaska Range. It is uplifted relative to the active foreland basin to the north. It is also deformed to various degree dependent on its location within the northern Alaska Range thrust system. Because this foreland basin sequence records the unroofing and northward propagation of the Alaska Range, direct dating of the Nenana Gravel, especially over wide spatial distribution along the Alaska Range, will substantially advance our understanding of the style and timing of deformation of the Alaska Range. At present though, age estimates for the Nenana Gravel are limited to a single maximum limiting age and uncertain minimum limiting age with no little or no insight as to the spatial variation in Nenana Gravel deposition timing. We present the first direct dates of deposition ages of the Nenana Gravel using cosmogenic nuclide burial dating. Results indicate that deposition of the Nenana Gravel began ca. 6.5 Ma, in stratigraphic agreement with a maximum limiting tephra age from the underlying Usibelli Group. Additional samples from the Nenana Gravel basal contact and higher in the section are presently underway. The resultant burial ages are amongst the oldest 26Al-10Be burial ages ever produced and highlight the potential of the method to directly date sediments in the Pliocene, particularly given recent advancements in the accelerator mass spectrometry measurement of 26Al/27Al isotope ratios.

  10. Range Corrections for Airborne Radar - A Joint STARS Study

    DTIC Science & Technology

    1984-05-01

    ESD-TR-84-169 MTR-9055 RANGE CORRECTIONS FOR AIRBORNE RADAR - A JOINT STARS STUDY By • _,.G. A. ROBERTSHAW MAY 1984 - Prepared for DEPUTY COMMANDER...NO NO Hanscom AFB, MA 01731 6460 11. TITLE •Include securi,•,cleaficatton) Range Corrections Tor Airborne Radar - A Joint STARS Study 12. PERSONAL...SUPPLEMENTARY NOTATION 17 COSATI CODES 18. SUBJECT TERMS (Continue on reuera if necemary and identify by block number) FIELD GROUP SUB GR. Airborne Radar

  11. A study of menarcheal age in India.

    PubMed

    Roberts, D F; Chinn, S; Girija, B; Singh, H D

    1977-03-01

    A study of menarcheal age was carried out in southern India. A logit method of analysis was applied to status quo data on 1267 Tamil and Telugu speaking girls aged 9 to 18 years in 3 schools catering for different socio-economic groups. There appears to be no relationship of menarcheal age with dietary pattern classified simply as vegetarian and non-vegetarian. Differences in median age at menarche between schools correspond well with the socio-economic differences between them. The median age in the most advantaged school (12-86 years) is comparable with that in recent studies in southern and eastern Europe, and may perhaps be in advance of some recent north-west European samples.

  12. The Algebro-geometric Study of Range Maps

    NASA Astrophysics Data System (ADS)

    Compagnoni, Marco; Notari, Roberto; Ruggiu, Andrea Alessandro; Antonacci, Fabio; Sarti, Augusto

    2017-02-01

    Localizing a radiant source is a problem of great interest to many scientific and technological research areas. Localization based on range measurements is at the core of technologies such as radar, sonar and wireless sensor networks. In this manuscript, we offer an in-depth study of the model for source localization based on range measurements obtained from the source signal, from the point of view of algebraic geometry. In the case of three receivers, we find unexpected connections between this problem and the geometry of Kummer's and Cayley's surfaces. Our work also gives new insights into the localization based on range differences.

  13. The Algebro-geometric Study of Range Maps

    NASA Astrophysics Data System (ADS)

    Compagnoni, Marco; Notari, Roberto; Ruggiu, Andrea Alessandro; Antonacci, Fabio; Sarti, Augusto

    2016-08-01

    Localizing a radiant source is a problem of great interest to many scientific and technological research areas. Localization based on range measurements is at the core of technologies such as radar, sonar and wireless sensor networks. In this manuscript, we offer an in-depth study of the model for source localization based on range measurements obtained from the source signal, from the point of view of algebraic geometry. In the case of three receivers, we find unexpected connections between this problem and the geometry of Kummer's and Cayley's surfaces. Our work also gives new insights into the localization based on range differences.

  14. High Prevalence of Hepatitis B Virus Infection in the Age Range of 20-39 Years Old Individuals in Lome

    PubMed Central

    Kolou, Malewe; Katawa, Gnatoulma; Salou, Mounerou; Gozo-Akakpo, Komlan Selom; Dossim, Sika; Kwarteng, Alexander; Prince-David, Mireille

    2017-01-01

    Background: Hepatitis B is a liver infection caused by the hepatitis B virus (HBV). It affects all women and men irrespective of age. Although sub-Saharan Africa is an area of high prevalence of this disease, data on the prevalence of acute and chronic HBV infections in this region remain to be widely documented. Objective: This study aimed to investigate the prevalence of HBV in relation to age in Centre Hospitalier Universitaire Campus (CHU-C), one of the two teaching hospitals of Lome, Togo. Method: The present study is a cross-sectional study about the prevalence of hepatitis B surface antigen (HBsAg) carriage from 2009 to 2011. All study participants were screened for HBsAg at the Immunology laboratory of CHU Campus of Lome. Results: One thousand two hundred individuals were screened for HBsAg from 2009-2011. The overall prevalence of HBV infection was 19.08%. This prevalence was significantly higher in men (25.00%) than women (14.80%). The highest prevalence of HBV was observed in age range of 20-29 years and 30-39 years with respectively 26.33% and 21.67%. The lowest prevalence was 6.08%, found in people over 50 years. Concerning the clinical indication of the test, the prevalence during the clinical abnormalities related to liver (CARL) was the highest (26.21%), followed by the systematic screening (SS) with 20.25% while the pre-operative assessment (POA) showed the lowest prevalence with 5.56%. Conclusion: The study shows the high prevalence of HBsAg carriage in young people. This could be used to enhance prevention and treatment of HBV infection in Togo. PMID:28217218

  15. Study Healthy Ageing and Intellectual Disabilities: Recruitment and Design

    ERIC Educational Resources Information Center

    Hilgenkamp, Thessa I. M.; Bastiaanse, Luc P.; Hermans, Heidi; Penning, Corine; van Wijck, Ruud; Evenhuis, Heleen M.

    2011-01-01

    Problems encountered in epidemiologic health research in older adults with intellectual disabilities (ID) are how to recruit a large-scale sample of participants and how to measure a range of health variables in such a group. This cross-sectional study into healthy ageing started with founding a consort of three large care providers with a total…

  16. Age of the Dawson Arkose, southwestern Air Force Academy, Colorado, and implications for the uplift history of the Front Range

    SciTech Connect

    Kluth, C.F.; Nelson, S.N. )

    1988-01-01

    An angular unconformity within the synorogenic Dawson Arkose (Late Cretaceous-Eocene) is preserved and exposed in areas south of Denver, Colorado, along the eastern side of the Front Range uplift. In the southwestern part of the Air Force Academy, the basal Dawson is concordant with the underlying Laramie and Fox Hills formations and dips 72-84{degree} eastward. Above an intraformational angular unconformity, younger units of the Dawson dip 24{degree}-46{degree} eastward. Smaller angular unconformities (10{degree}{plus minus}), and beds with gradually decreasing dip occur higher in the Dawson section. Rocks above the largest unconformity contain a rich palynomorph assemblage of Late Maestrichtain age. These data indicate that approximately 30{degree}-40{degree}, and possibly as much as approximately 70{degree}, of tilting of the underlying rocks occurred during the Late Maestrichtian (66-70 Ma). It is also possible that approximately 30{degree}-40{degree} of the tilting of the Late Cretaceous rocks occurred between latest Maestrichtian and Eocene (approximately 45 Ma). These results suggest that the transition from a tectonically quiet marine environment to a non-marine, tectonically active condition took place rapidly, probably within a few million years. When combined with published data, the authors study indicates that the Front Range has different tectonic histories on its eastern and its western side, and that the deformation is diachronous along the strike of the eastern side of the Front Range.

  17. K-Ar ages of allochthonous mafic and ultramafic complexes and their metamorphic aureoles, Western Brooks Range, Alaska

    SciTech Connect

    Boak, J.L.; Turner, D.L.; Wallace, W.K.; Moore, T.E.

    1985-04-01

    New K-Ar ages from allochthonous mafic and ultramafic complexes of the western Brooks Range (Brooks Range ophiolite) show that igneous rocks yielded ages nearly identical to those of underlying metamorphic aureole rocks. Dated rocks of the Misheguk igneous sequence from Tumit Creek consist of (1) hornblende gabbro with minor greenschist and lower grade alteration, hornblende age 147.2 +/- 4.4 Ma; and (2) hornblende-bearing diorite, also slightly altered, age 155.8 +/- 4.7 Ma. Both samples come from presumed higher levels of the Misheguk sequence. Dated samples of metamorphic aureole rocks come from outcrops near Kismilot Creek and lie structurally beneath the Iyikrok Mountain peridotite body. The rocks consist of amphibolite and garnet-bearing biotite-hornblende gneiss considered to be metamorphosed Copter igneous sequence and related sedimentary rocks. Hornblende ages are 154.2 +/- 4.6 Ma and 153.2 +/- 4.6 Ma. metamorphism is clearly related to the structurally overlying perioditite, as the degree of alteration decreases downward. The authors suggest that the K-Ar ages of these rocks represent the effects of thermal metamorphism post-dating igneous crystallization, and are related to tectonic emplacement of the complex. Earlier K-Ar data on igneous rocks give similar ages and have been interpreted as reflecting tectonothermal events. The age of igneous crystallization of the mafic and ultramafic rocks of the Misheguk igneous sequence remains uncertain.

  18. Development of an equation to predict muscle volume of elbow flexors for men and women with a wide range of age.

    PubMed

    Akagi, Ryota; Takai, Yohei; Kato, Emika; Wakahara, Taku; Ohta, Megumi; Kanehisa, Hiroaki; Fukunaga, Tetsuo; Kawakami, Yasuo

    2010-03-01

    The present study examined the age-related changes in muscle thickness (MT) and volume (MV) of elbow flexors and developed a prediction equation of the MV based on the MT applicable to men and women with a wide range of age. The MT and MV were determined from a single ultrasonographic image and multiple magnetic resonance imaging scans, respectively, in 72 men and 75 women aged 19-77 year. As a result of examining the age-MT and age-MV relationships by calculation of partial correlation coefficients with the control variable of gender, MV was decreased with aging whereas the corresponding decline in MT was not significant. The subjects were randomly separated into either a validation (38 men and 42 women) or a cross-validation (34 men and 33 women) group, and a multiple regression equation to estimate MV using not only MT but also upper arm length (L), age and gender as independent variables [MV (cm(3)) = 60.8 x MT (cm) + 6.48 x L (cm) - 0.709 x age (year) + 51.4 x gender (0 women, 1 men) - 187.4] was validated and cross-validated. Thus, the prediction equation for MV of elbow flexors newly developed was shown to be applicable to men and women with a wide range of age.

  19. Designing Intervention Studies: Selected Populations, Range Restrictions, and Statistical Power

    ERIC Educational Resources Information Center

    Miciak, Jeremy; Taylor, W. Pat; Stuebing, Karla K.; Fletcher, Jack M.; Vaughn, Sharon

    2016-01-01

    An appropriate estimate of statistical power is critical for the design of intervention studies. Although the inclusion of a pretest covariate in the test of the primary outcome can increase statistical power, samples selected on the basis of pretest performance may demonstrate range restriction on the selection measure and other correlated…

  20. Chicago Healthy Aging Study: Objectives and Design

    PubMed Central

    Pirzada, Amber; Reid, Kathryn; Kim, Daniel; Garside, Daniel B.; Lu, Brandon; Vu, Thanh-Huyen T.; Lloyd-Jones, Donald M.; Zee, Phyllis; Liu, Kiang; Stamler, Jeremiah; Daviglus, Martha L.

    2013-01-01

    Investigators in the Chicago Healthy Aging Study (CHAS) reexamined 1,395 surviving participants aged 65–84 years (28% women) from the Chicago Heart Association Detection Project in Industry (CHA) 1967–1973 cohort whose cardiovascular disease (CVD) risk profiles were originally ascertained at ages 25–44 years. CHAS investigators reexamined 421 participants who were low-risk (LR) at baseline and 974 participants who were non-LR at baseline. LR was defined as having favorable levels of 4 major CVD risk factors: serum total cholesterol level <200 mg/dL and no use of cholesterol-lowering medication; blood pressure 120/≤80 mm Hg and no use of antihypertensive medication; no current smoking; and no history of diabetes or heart attack. While the potential of LR status in overcoming the CVD epidemic is being recognized, the long-term association of LR with objectively measured health in older age has not been examined. It is hypothesized that persons who were LR in 1967–1973 and have survived to older age will have less clinical and subclinical CVD, lower levels of inflammatory markers, and better physical performance/functioning and sleep quality. Here we describe the rationale, objectives, design, and implementation of this longitudinal epidemiologic study, compare baseline and follow-up characteristics of participants and nonparticipants, and highlight the feasibility of reexamining study participants after an extended period postbaseline with minimal interim contact. PMID:23669655

  1. Unbiased Average Age-Appropriate Atlases for Pediatric Studies

    PubMed Central

    Fonov, Vladimir; Evans, Alan C.; Botteron, Kelly; Almli, C. Robert; McKinstry, Robert C.; Collins, D. Louis

    2010-01-01

    Spatial normalization, registration, and segmentation techniques for Magnetic Resonance Imaging (MRI) often use a target or template volume to facilitate processing, take advantage of prior information, and define a common coordinate system for analysis. In the neuroimaging literature, the MNI305 Talairach-like coordinate system is often used as a standard template. However, when studying pediatric populations, variation from the adult brain makes the MNI305 suboptimal for processing brain images of children. Morphological changes occurring during development render the use of age-appropriate templates desirable to reduce potential errors and minimize bias during processing of pediatric data. This paper presents the methods used to create unbiased, age-appropriate MRI atlas templates for pediatric studies that represent the average anatomy for the age range of 4.5–18.5 years, while maintaining a high level of anatomical detail and contrast. The creation of anatomical T1-weighted, T2-weighted, and proton density-weighted templates for specific developmentally important age-ranges, used data derived from the largest epidemiological, representative (healthy and normal) sample of the U.S. population, where each subject was carefully screened for medical and psychiatric factors and characterized using established neuropsychological and behavioral assessments. . Use of these age-specific templates was evaluated by computing average tissue maps for gray matter, white matter, and cerebrospinal fluid for each specific age range, and by conducting an exemplar voxel-wise deformation-based morphometry study using 66 young (4.5–6.9 years) participants to demonstrate the benefits of using the age-appropriate templates. The public availability of these atlases/templates will facilitate analysis of pediatric MRI data and enable comparison of results between studies in a common standardized space specific to pediatric research. PMID:20656036

  2. Geomagnetic Investigation of Sandstone Dikes of the Colorado Front Range, for Determination of Age and Mode of Emplacement

    NASA Astrophysics Data System (ADS)

    Freedman, D.; Petronis, M. S.; Siddoway, C. S.

    2012-12-01

    In the Colorado Front Range, an array of sandstone dikes has intrigued geologists for over a century (Cross 1894,GSAB, 5, 525). Within their crystalline host, the dikes reach widths >7m and have a lateral extent of 70km along the Ute Pass Fault (UPF). The essential questions of sediment source, emplacement mode, and age of the dikes are unanswered. We present new paleomagnetic, rock magnetic, and anisotropy of magnetic susceptibility (AMS) results used to determine the age and emplacement behavior of the dikes. The eleven dikes selected for magnetic studies have sharp, planar margins, and share the systematic geometry of the NW striking subvertical dike array. They exhibit little or no overprint by brittle fracturing/shear associated with the UPF. Our approach involved the use of paleomagnetic techniques to isolate the characteristic remanent magnetization (ChRM), which we used to limit the age of the dikes' magnetization. Anisotropy of magnetic susceptibility (AMS),arising from alignment of detrital magnetite, serves as a proxy for the orientation of flow during dike emplacement. U-Pb detrital zircon ages, obtained previously, did not provide a useful constraint on emplacement age because the dominant age matches that of the prevalent host,1.03Ga Pikes Peak Granite. IRM acquisition experiments were performed to identify the principal magnetic phases as a mixture of Fe-Ti oxide phases, likely to be low-Ti magnetite and hematite. The sandstone consists of sub-rounded to rounded sand-sized quartz, angular feldspar (<5%), and detrital magnetite; selected samples have uniform grain size and uniform color arising from hematite cement. Although direct cover relationships are not preserved, a portion of the study sites are proximal to in situ near-horizontal sedimentary cover rocks that offer evidence against large tectonic rotation. Cores were collected using a gas-powered drill with a diamond bit and oriented using a sun compass. Where possible, cores were obtained on

  3. Concept definition study for an extremely large aerophysics range facility

    NASA Technical Reports Server (NTRS)

    Swift, H.; Witcofski, R.

    1992-01-01

    The development of a large aerophysical ballistic range facility is considered to study large-scale hypersonic flows at high Reynolds numbers for complex shapes. A two-stage light gas gun is considered for the hypervelocity launcher, and the extensive range tankage is discussed with respect to blast suppression, model disposition, and the sabot impact tank. A layout is given for the large aerophysics facility, and illustrations are provided for key elements such as the guide rail. The paper shows that such a facility could be used to launch models with diameters approaching 250 mm at velocities of 6.5 km/s with peak achievable accelerations of not more than 85.0 kgs. The envisioned range would provide gas-flow facilities capable of controlling the modeled quiescent atmospheric conditions. The facility is argued to be a feasible and important step in the investigation and experiment of such hypersonic vehicles as the National Aerospace Plane.

  4. Concept definition study for an extremely large aerophysics range facility

    NASA Astrophysics Data System (ADS)

    Swift, H.; Witcofski, R.

    1992-07-01

    The development of a large aerophysical ballistic range facility is considered to study large-scale hypersonic flows at high Reynolds numbers for complex shapes. A two-stage light gas gun is considered for the hypervelocity launcher, and the extensive range tankage is discussed with respect to blast suppression, model disposition, and the sabot impact tank. A layout is given for the large aerophysics facility, and illustrations are provided for key elements such as the guide rail. The paper shows that such a facility could be used to launch models with diameters approaching 250 mm at velocities of 6.5 km/s with peak achievable accelerations of not more than 85.0 kgs. The envisioned range would provide gas-flow facilities capable of controlling the modeled quiescent atmospheric conditions. The facility is argued to be a feasible and important step in the investigation and experiment of such hypersonic vehicles as the National Aerospace Plane.

  5. 40Ar 39Ar Ages and tectonic setting of ophiolite from the Neyriz area, southeast Zagros Range, Iran

    USGS Publications Warehouse

    Lanphere, M.A.; Pamic, J.

    1983-01-01

    An ophiolite, considered to be an allochthonous fragment of Tethyan oceanic crust and mantle, crops out near Neyriz in the Zagros Range, Iran. 40Ar 39Ar ages ranging from 76.8 ?? 23.8 Ma to 105 ?? 23.3 Ma were measured on hornblende from five samples of plagiogranite and diabase from the ophiolite. The most precise ages are 85.9 ?? 3.8 Ma for a diabase and 83.6 ?? 8.4 Ma for a plagiogranite. The weighted mean age of hornblende from the five samples is 87.5 ?? 7.2 Ma which indicates that the igneous part of the Neyriz ophiolite formed during the early part of the Late Cretaceous. Pargasite from amphibolite below peridotite of the Neyriz ophiolite has a 40Ar 39Ar age of 94.9 ?? 7.6 Ma. The pargasite age agrees within analytical uncertainty with the ages measured on diabase and plagiogranite. Comparable ages have been measured on igneous rocks from the Samail ophiolite of Oman and on amphibolite below peridotite of the Samail ophiolite. ?? 1983.

  6. Age-Related Increases in Long-Range Connectivity in Fetal Functional Neural Connectivity Networks In Utero

    PubMed Central

    Thomason, Moriah E.; Grove, Lauren E.; Lozon, Tim A.; Vila, Angela M.; Ye, Yongquan; Nye, Matthew J.; Manning, Janessa H.; Pappas, Athina; Hernandez-Andrade, Edgar; Yeo, Lami; Mody, Swati; Berman, Susan; Hassan, Sonia S.; Romero, Roberto

    2015-01-01

    Formation of operational neural networks is one of the most significant accomplishments of human fetal brain growth. Recent advances in functional magnetic resonance imaging (fMRI) have made it possible to obtain information about brain function during fetal development. Specifically, resting-state fMRI and novel signal covariation approaches have opened up a new avenue for non-invasive assessment of neural functional connectivity (FC) before birth. Early studies in this area have unearthed new insights about principles of prenatal brain function. However, very little is known about the emergence and maturation of neural networks during fetal life. Here, we obtained cross-sectional rs-fMRI data from 39 fetuses between 24 and 38 weeks postconceptual age to examine patterns of connectivity across ten neural FC networks. We identified primitive forms of motor, visual, default mode, thalamic, and temporal networks in the human fetal brain. We discovered the first evidence of increased long-range, cerebral-cerebellar, cortical-subcortical, and intra-hemispheric FC with advancing fetal age. Continued aggregation of data about fundamental neural connectivity systems in utero is essential to establishing principles of connectomics at the beginning of human life. Normative data provides a vital context against which to compare instances of abnormal neurobiological development. PMID:25284273

  7. Age-related increases in long-range connectivity in fetal functional neural connectivity networks in utero.

    PubMed

    Thomason, Moriah E; Grove, Lauren E; Lozon, Tim A; Vila, Angela M; Ye, Yongquan; Nye, Matthew J; Manning, Janessa H; Pappas, Athina; Hernandez-Andrade, Edgar; Yeo, Lami; Mody, Swati; Berman, Susan; Hassan, Sonia S; Romero, Roberto

    2015-02-01

    Formation of operational neural networks is one of the most significant accomplishments of human fetal brain growth. Recent advances in functional magnetic resonance imaging (fMRI) have made it possible to obtain information about brain function during fetal development. Specifically, resting-state fMRI and novel signal covariation approaches have opened up a new avenue for non-invasive assessment of neural functional connectivity (FC) before birth. Early studies in this area have unearthed new insights about principles of prenatal brain function. However, very little is known about the emergence and maturation of neural networks during fetal life. Here, we obtained cross-sectional rs-fMRI data from 39 fetuses between 24 and 38 weeks postconceptual age to examine patterns of connectivity across ten neural FC networks. We identified primitive forms of motor, visual, default mode, thalamic, and temporal networks in the human fetal brain. We discovered the first evidence of increased long-range, cerebral-cerebellar, cortical-subcortical, and intra-hemispheric FC with advancing fetal age. Continued aggregation of data about fundamental neural connectivity systems in utero is essential to establishing principles of connectomics at the beginning of human life. Normative data provides a vital context against which to compare instances of abnormal neurobiological development.

  8. The exclusion of a significant range of ages in a massive star cluster.

    PubMed

    Li, Chengyuan; de Grijs, Richard; Deng, Licai

    2014-12-18

    Stars spend most of their lifetimes on the main sequence in the Hertzsprung-Russell diagram. The extended main-sequence turn-off regions--containing stars leaving the main sequence after having spent all of the hydrogen in their cores--found in massive (more than a few tens of thousands of solar masses), intermediate-age (about one to three billion years old) star clusters are usually interpreted as evidence of internal age spreads of more than 300 million years, although young clusters are thought to quickly lose any remaining star-forming fuel following a period of rapid gas expulsion on timescales of order 10(7) years. Here we report, on the basis of a combination of high-resolution imaging observations and theoretical modelling, that the stars beyond the main sequence in the two-billion-year-old cluster NGC 1651, characterized by a mass of about 1.7 × 10(5) solar masses, can be explained only by a single-age stellar population, even though the cluster has a clearly extended main-sequence turn-off region. The most plausible explanation for the existence of such extended regions invokes a population of rapidly rotating stars, although the secondary effects of the prolonged stellar lifetimes associated with such a stellar population mixture are as yet poorly understood. From preliminary analysis of previously obtained data, we find that similar morphologies are apparent in the Hertzsprung-Russell diagrams of at least five additional intermediate-age star clusters, suggesting that an extended main-sequence turn-off region does not necessarily imply the presence of a significant internal age dispersion.

  9. Aging studies of Kevlar 49 fibers

    SciTech Connect

    Morgan, R.J.; Pruneda, C.O.; Kong, F.M.

    1983-11-01

    The aging mechanisms in service environment of Kevlar 49 fibers, E.I. duPont, (poly(p-phenylene)terephthalamide) are reviewed. The principal aging mechanisms considered are (i) u.v.-, (ii) hydrolytic- and (iii) stress-induced macromolecular chain scission and microvoid growth. U.V.-induced strength degradation can be significant as a result of photo-oxidative and photodegradative radical formation but in Kevlar 49-epoxy composites only the exterior yarn layer is deteriorated. Hydrolytic chain scission of the amide linkage and corresponding fiber strength deterioration is considered in terms of R.H., time, temperature and stress level. The rates of hydrolytic degradation at 100% R.H. in the 100 to 200/sup 0/C range are reported. The estimated rates of fiber degradation in various service environment conditions are also reported and shown not to be serious. The stress-induced aging of Kevlar 49 fibers is considered in terms of the growth and coalescence of inherent microvoids along the fiber axis together with the generation of new microvoids. (These growth processes involve no detectable macromolecular chain scission or deterioration in fiber strength.) At a critical microvoid volume fraction catastrophic failure occurs by interconnection of such voids.

  10. Cosmogenic exposure-age chronologies of Pinedale and Bull Lake glaciations in greater Yellowstone and the Teton Range, USA

    USGS Publications Warehouse

    Licciardi, J.M.; Pierce, K.L.

    2008-01-01

    We have obtained 69 new cosmogenic 10Be surface exposure ages from boulders on moraines deposited by glaciers of the greater Yellowstone glacial system and Teton Range during the middle and late Pleistocene. These new data, combined with 43 previously obtained 3He and 10Be ages from deposits of the northern Yellowstone outlet glacier, establish a high-resolution chronology for the Yellowstone-Teton mountain glacier complexes. Boulders deposited at the southern limit of the penultimate ice advance of the Yellowstone glacial system yield a mean age of 136??13 10Be ka and oldest ages of ???151-157 10Be ka. These ages support a correlation with the Bull Lake of West Yellowstone, with the type Bull Lake of the Wind River Range, and with Marine Isotope Stage (MIS) 6. End moraines marking the maximum Pinedale positions of outlet glaciers around the periphery of the Yellowstone glacial system range in age from 18.8??0.9 to 16.5??1.4 10Be ka, and possibly as young as 14.6??0.7 10Be ka, suggesting differences in response times of the various ice-cap source regions. Moreover, all dated Pinedale terminal moraines in the greater Yellowstone glacial system post-date the Pinedale maximum in the Wind River Range by ???4-6 kyr, indicating a significant phase relationship between glacial maxima in these adjacent ranges. Boulders on the outermost set and an inner set of Pinedale end moraines enclosing Jenny Lake on the eastern Teton front yield mean ages of 14.6??0.7 and 13.5??1.1 10Be ka, respectively. The outer Jenny Lake moraines are partially buried by outwash from ice on the Yellowstone Plateau, hence their age indicates a major standstill of an expanded valley glacier in the Teton Range prior to the Younger Dryas, followed closely by deglaciation of the Yellowstone Plateau. These new glacial chronologies are indicative of spatially variable regional climate forcing and temporally complex patterns of glacier responses in this region of the Rocky Mountains during the Pleistocene

  11. Fission track ages of detrital zircons from sandstones of the Umpqua Group and Tyee Formation, Oregon coast range

    SciTech Connect

    Vance, J.A. . Dept. of Geological Sciences); Brandon, M.T. . Dept. of Geology and Geophysics)

    1993-04-01

    Detrital zircons from Paleogene sandstones of the Umpqua Group (UG) and the Tyee Fm (TF) yield contrasting FT age patterns which distinguish these two units and cast new light on their regional extent, correlation and provenance. In the Roseburg (Rg) area of the southern Oregon Coast Range, where most widely exposed, the UG consists of continental and marine clastic beds which overlie submarine lavas of the Coast Range Basalt. K-Ar And Ar-Ar dating of the basement basalts shows a younging trend from about 62 Ma at Rg at the south to 56 Ma at Siletz River and 53 Ma at Tillamook to the north. Detrital zircons from the Rg area are characterized by old FT ages. Of 192 grains dated, 90% are older than 90 Ma; the median age is 129 Ma. A diorite cobble from an UG conglomerate gave a zircon FT age of 105 Ma. These ages point to a source in the Jurassic plutons in the Klamath Mountains nearby to the south. The authors have determined FT cooling ages of 110 and 120 Ma for zircons from the Mt. Ashland and Grants Pass plutons. Continental and shallow marine clastic strata of the TF overly the UG beds west of Rg. The UG is not widely exposed north of Rg where it thins and pinches out above the Coast Range Basalt and is overlain by a northern turbidite facies of the TF. Three TF sandstones from the latitude of Rg and three others from west and south of Corvallis yielded distinctive and identical zircon FT age patterns characterized by young ages. Of 335 zircons dated, 80% are younger than 90 Ma; the median age is 61 Ma. This maximum age is very close to that of the overlying Tillamook and Fisher Fms. The flood of detrital zircons with young FT ages in the TF marks the abrupt change from a nearby Klamath source for the UG beds to a distant, easterly TF source in a recently uplifted plutonic-metamorphic terrane.

  12. Risk of Developmental Delay Increases Exponentially as Gestational Age of Preterm Infants Decreases: A Cohort Study at Age 4 Years

    ERIC Educational Resources Information Center

    Kerstjens, Jorien M.; de Winter, Andrea F.; Bocca-TJeertes, Inger F.; Bos, Arend F.; Reijneveld, Sijmen A.

    2012-01-01

    Aim: The aim of the study was to assess the influence of decreasing gestational age on the risk of developmental delay in various domains at age 4 years among children born at a wide range of gestational ages. Method: In a community-based cohort, the parents of 1439 preterm-born children (24 0/7 to 35 6/7wks) and 544 term-born children (38 0/7 to…

  13. Glenohumeral Joint Range of Motion in Elite Male Golfers: A Pilot Study

    PubMed Central

    Meria, Erik; Nee, Bob; Davidson, Greg

    2008-01-01

    Background Shoulder injuries account for up to 17% of all golf related musculoskeletal injuries. One cause may be the repetitive stresses applied to the lead shoulder during the backswing and follow-through phases, which may contribute to the frequency of these injuries. The “elite” golfer may be pre-disposed to developing a shoulder injury based upon the reported adaptations to the glenohumeral joint. Objective To examine and compare bilateral glenohumeral joint rotational range of motion in elite golfers using standard goniometric procedures. Methods Twenty-four “elite” male golfers were recruited for this study. Glenohumeral internal (IR) and external rotation (ER) passive range of motion was measured bilaterally at 90° of abduction using a standard universal goniometer. Paired t-tests were utilized to statistically compare the rotational range of motion patterns between the lead and the trailing shoulder. Results No statistical differences existed between each shoulder for mean IR or mean ER measures. This finding was consistent throughout different age groups. External rotation measurements were greater than IR measurements in both extremities. Discussion and Conclusion Unlike other sports requiring repetitive shoulder function, the “elite” golfers sampled in this pilot investigation did not demonstrate a unique passive range of motion pattern between the lead and trailing shoulders. Factors, including subjects' age, may have confounded the findings. Further studies are warranted utilizing cohorts of golfers with matching age and skill levels. Additional shoulder range of motion measures should be evaluated. PMID:21509130

  14. XTX8003 Aging Study Status Report

    SciTech Connect

    Cates, M.; Coleman, K.; Foster, P.; Klassen, S.; Loyola, V.

    1999-03-08

    XTX8003 is an extrudable explosive composed of 80% PETN and 20% Sylgard 182 (polydimethylsiloxane). Knowledge of the aging characteristics of XTX8003 is desired to understand the relationship between chemical and physical changes and performance. This understanding will allow improved assessment of the current state and also projected lifetime of components that contain this material. A literature search revealed few published studies of the aging behavior of XTX8003 or a chemically similar material, LX-13. Two studies showed that detonation velocity had decreased after storage at 70 C for two years. Another study showed a 30% decrease in target penetration by conical shaped charge after 12 weeks of storage at 82 C. Only one study was found which evaluated chemical and physical changes, but no information was available to correlate performance degradation to chemical and physical changes in the material. In summary, the major changes seen in aged XTX8003 are in detonation velocity and particle morphology, but particle morphology does not appear to be the determining factor in the loss of detonation velocity. The study will continue at least 24 months, at which time the data will be evaluated to determine how best to continue with the remaining test samples.

  15. Does Sensory Function Decline Independently or Concomitantly with Age? Data from the Baltimore Longitudinal Study of Aging

    PubMed Central

    Gadkaree, Shekhar K.; Sun, Daniel Q.; Li, Carol; Lin, Frank R.; Ferrucci, Luigi; Simonsick, Eleanor M.

    2016-01-01

    Objectives. To investigate whether sensory function declines independently or in parallel with age within a single individual. Methods. Cross-sectional analysis of Baltimore Longitudinal Study of Aging (BLSA) participants who underwent vision (visual acuity threshold), proprioception (ankle joint proprioceptive threshold), vestibular function (cervical vestibular-evoked myogenic potential), hearing (pure-tone average audiometric threshold), and Health ABC physical performance battery testing. Results. A total of 276 participants (mean age 70 years, range 26–93) underwent all four sensory tests. The function of all four systems declined with age. After age adjustment, there were no significant associations between sensory systems. Among 70–79-year-olds, dual or triple sensory impairment was associated with poorer physical performance. Discussion. Our findings suggest that beyond the common mechanism of aging, other distinct (nonshared) etiologic mechanisms may contribute to decline in each sensory system. Multiple sensory impairments influence physical performance among individuals in middle old-age (age 70–79). PMID:27774319

  16. Color Range and Color Distribution of Healthy Human Gingiva: a Prospective Clinical Study.

    PubMed

    Ho, Daniel K; Ghinea, Razvan; Herrera, Luis J; Angelov, Nikola; Paravina, Rade D

    2015-12-22

    The aim of this study is to compile a comprehensive database on color range and color distribution of healthy human gingiva by age, gender and ethnicity. Spectral reflection of keratinized gingiva at upper central incisors was measured by spectroradiometer and converted into CIELAB values. Lightness range (ΔL*) for all groups together was 26.8. Corresponding a* (green-red) and b* (blue-yellow) ranges (Δa* and Δb*) were 18.3 and 13.0. Significant differences (p < 0.05) were recorded by age for L* and a* coordinates, by gender for b* coordinate, and by ethnicity for L*, a* and b* coordinates. R(2)-values between color coordinates were 0.01 (L*/a*), 0.03 (L*/b*), and 0.12 (a*/b*). The smallest color differences were recorded between age groups 46-60 and 60 + (ΔE* = 0.9), and between Caucasians and Hispanics (ΔE* = 1.1). Color difference by gender was 1.3. When total L*a*b* ranges were divided into four equal segments, 51.7% of subjects had L* value within the third segment (from lightest to darkest), 47.1% had a* value within the third segment (from less red to redder), and 59.3% had b* value within the second segment (from less yellow to yellower). It was found that ethnicity and age had statistically significant influence on the color of human gingiva.

  17. Tectonically controlled fan delta and submarine fan sedimentation of late Miocene age, southern Temblor Range, California

    USGS Publications Warehouse

    Ryder, Robert T; Thomson, Alan

    1989-01-01

    The Santa Margarita Formation in the southern Temblor Range, composed of conglomerate and subordinate sandstone, evolved as a large complex of fan deltas and submarine fans in late Miocene time. An 80 to 90-m.y.-old granitic basement of the Salinian block and an accompanying 23.5-m.y.-old volcanic field now located in the northern Gabilan Range and the Pinnacles area, respectively, were the primary source terranes. In general, the fan deltas crop out along the west side of the southern Temblor Range, whereas the proximal parts of the submarine fans crop out along the east side of the range. The fan deltas consist of subaerial topset beds and low-angle basinward-dipping subaqueous foreset beds. Strata interpreted to be topset beds are composed largely of conglomerate with thick to very thick horizontal beds and matrix-supported clasts. Most of the thick to very thick conglomerate beds are internally massive and disorganized. Strata interpreted as foreset beds are composed of thick-bedded, large-scale, low-angle, cross-stratified conglomerate and sandstone units which commonly are internally massive. Abundant molluskan macrofossils such as Ostrea and Pecten are present in the subaqueous foreset beds; many have been displaced downslope from their original site of deposition. Conglomerate- and sandstone-filled submarine canyons, through which coarse-grained detritus was transported to the adjacent submarine fans, locally have cut into the foreset beds of the fan deltas. These submarine canyon deposits are generally better stratified than adjacent foreset-bed deposits, and they consist of thick horizontal beds, internally massive or normally graded, arranged in fining- and thinning-upward sequences. Isolated and composite conglomerate- and sandstone-filled channels, which crop out on the east flank of the southern Temblor Range, are interpreted as proximal submarine-fan channel deposits. These channel-form conglomerate and sandstone deposits are characterized by thick

  18. Aging, Spirituality, and Time: A Qualitative Study

    PubMed Central

    Black, Helen K.; Hannum, Susan M.

    2015-01-01

    We examined the concepts of aging, time, spirituality, and future care needs in four randomly selected informants from a group of 54 never-married childless older women. Using data from the Generativity and Lifestyles of Older Women (GLOW) study, we questioned how women’s perceptions of these concepts came together in current older age. We employed cultural theory, (our theoretical framework), ethnography, (our methodological framework), and phenomenology, (our philosophical foundation) to produce a portrait of each woman interviewed. Through a three-session interview process, we elicited the women’s life stories, reasons for childlessness, and topics that emerged as significant to the women, including aging, a sense of time remaining, and spirituality. A key finding was that the context of each woman’s life, both biographical and historical, transpired as a foundation for these concepts. That is, a woman’s “place in time” shaped their experiences of aging, as well as her reasons for childlessness and perceptions of finitude. PMID:26539067

  19. The othering of old age: Insights from Postcolonial Studies.

    PubMed

    van Dyk, Silke

    2016-12-01

    When it comes to old age, we are witnessing almost revolutionary changes at the present time. After decades of ignorance and lack of public interest, old age has fundamentally been re-negotiated. A diverse range of authors have diagnosed the growing bifurcation of old age into a rather independent and capable Third Age and a deep old Fourth Age that is characterized by sickness, frailty and dependency. Against this backdrop, many gerontologists claim that the so-called young-old are praised and valued for their (ongoing) "sameness" in terms of midlife-norms and capabilities, whereas the oldest old are increasingly excluded from humanity by radical "othering". Taking up this diagnosis, the article elaborates on this growing polarization within later life: Based on empirical research on the re-negotiation of old age in Germany, this contribution argues that the juxtaposition of "sameness" and "otherness" obscures the true character of the polarization, particularly with regard to the social role of the Third Age. Instead of sameness and otherness, we rather witness different processes of othering, with the young-old being valued as the other and the oldest old being disdained as the other. Despite the existence of profound critical analyses of the abjection associated with the Fourth Age as well as a considerable amount of literature on old age activation and the new role of the young-old, the specific point of this article's concern-the othering of the Third Age-has been completely neglected. The article discusses the reasons for this gap in more detail and will indicate to what extent concepts from Postcolonial Studies may help us to understand the dual process of othering-glorification and abjection.

  20. Cohort profile: the European Male Ageing Study.

    PubMed

    Lee, David M; Pye, Stephen R; Tajar, Abdelouahid; O'Neill, Terence W; Finn, Joseph D; Boonen, Steven; Bartfai, Gyorgy; Casanueva, Felipe F; Forti, Gianni; Giwercman, Aleksander; Han, Thang S; Huhtaniemi, Ilpo T; Kula, Krzysztof; Lean, Michael E J; Pendleton, Neil; Punab, Margus; Silman, Alan J; Vanderschueren, Dirk; Wu, Frederick C W

    2013-04-01

    The European Male Ageing Study (EMAS) was designed to examine the hypothesis that inter-individual and regional variability in symptomatic dysfunctions, alterations in body composition and health outcomes in ageing men can be explained by different rates of decline in anabolic hormones, the most important of which being testosterone. Between 2003 and 2005, 3369 community-dwelling men, aged between 40 and 79 years, were recruited from population-based registers in eight European centres to participate in the baseline survey, with follow-up investigations performed a median of 4.3 years later. Largely, identical questionnaire instruments and clinical investigations were used in both phases to capture contemporaneous data on general health (including cardiovascular diseases and chronic conditions), physical and cognitive functioning, mental health, sexual function, quality of life, bone health, chronic pain, disease biomarkers, hormones (sex hormones and metabolic hormones) and genetic polymorphisms. EMAS actively encourages new collaborations, data sharing for validation studies and participation in genetic study consortia. Potential collaborators should contact the principal investigator (F.C.W.W.) in the first instance.

  1. Studying disability trends in aging populations.

    PubMed

    Gu, Danan; Gomez-Redondo, Rosa; Dupre, Matthew E

    2015-03-01

    This article reviews the current literature on disability trends in aging populations and proposes a framework for studying disability trends built upon existing models of disablement. In addition to considering disablement and its associated factors, our framework also includes factors at population level and the interplays among personal resources and health behaviors, intervention programs, technological advances, and the consequences of disability trends in the context of life course and socio-ecological perspective. The framework is abbreviated FE-BRIT-SE to denote individual-level (F)ixed attributes, including genetic factors, personality, age, sex, and earlier life conditions, and the (E)nvironment; individual (B)ehaviors, (R)esources, (I)nterventions, (T)echnology; and (S)ocioeconomic and (E)cological consequences of disability trends. The overview offers an integrated framework for understanding the disablement process, trends and their complex milieu of causes and consequences.

  2. Establishment of Age- and Gender-Specific Reference Ranges for 36 Routine and 57 Cell Population Data Items in a New Automated Blood Cell Analyzer, Sysmex XN-2000

    PubMed Central

    Park, Sang Hyuk; Lee, Bo-Ra; Kim, Mi-Jeong; Han, Min-Young; Cho, Young-Uk; Jang, Seongsoo

    2016-01-01

    We established age- and gender-specific reference ranges for the 36 routine complete blood cell (CBC) and 57 cell population data (CPD) items in the Sysmex XN-2000 (Sysmex, Japan). In total, 280 peripheral blood samples were obtained from an equal number of healthy adults. Values for 36 routine items and 57 CPD items were obtained for each sample, and the results were categorized into six subgroups (N>39 in each subgroup) according to patient age (20-40, 41-60, and >60 yr) and gender (male and female), and compared with respect to age and gender differences. The majority of data items (22 of 36 routine CBC items and 44 of 57 CPD items) exhibited significant differences (P≤0.05) in their results with respect to age or gender, and several red cell-, lymphocyte-, and platelet-related data tended to decrease in women or older adults. These results provide a basis for establishing age- and gender-specific reference ranges for routine and CPD items in Sysmex XN-2000. Furthermore, these reference ranges could be used to determine clinical significance for new items of Sysmex XN-2000 in further studies. PMID:26915613

  3. Establishment of Age- and Gender-Specific Reference Ranges for 36 Routine and 57 Cell Population Data Items in a New Automated Blood Cell Analyzer, Sysmex XN-2000.

    PubMed

    Park, Sang Hyuk; Park, Chan Jeoung; Lee, Bo Ra; Kim, Mi Jeong; Han, Min Young; Cho, Young Uk; Jang, Seongsoo

    2016-05-01

    We established age- and gender-specific reference ranges for the 36 routine complete blood cell (CBC) and 57 cell population data (CPD) items in the Sysmex XN-2000 (Sysmex, Japan). In total, 280 peripheral blood samples were obtained from an equal number of healthy adults. Values for 36 routine items and 57 CPD items were obtained for each sample, and the results were categorized into six subgroups (N>39 in each subgroup) according to patient age (20-40, 41-60, and >60 yr) and gender (male and female), and compared with respect to age and gender differences. The majority of data items (22 of 36 routine CBC items and 44 of 57 CPD items) exhibited significant differences (P≤0.05) in their results with respect to age or gender, and several red cell-, lymphocyte-, and platelet-related data tended to decrease in women or older adults. These results provide a basis for establishing age- and gender-specific reference ranges for routine and CPD items in Sysmex XN-2000. Furthermore, these reference ranges could be used to determine clinical significance for new items of Sysmex XN-2000 in further studies.

  4. Aging Studies of VCE Dismantlement Returns

    SciTech Connect

    Letant, S; Alviso, C; Pearson, M; Albo, R; Small, W; Wilson, T; Chinn, S; Maxwell, R

    2011-10-17

    VCE is an ethylene/vinyl acetate/vinyl alcohol terpolymer binder for filled elastomers which is designed to accept high filler loadings. Filled elastomer parts consist of the binder (VCE), a curing agent (Hylene MP, diphenol-4-4{prime}-methylenebis(phenylcarbamate)), a processing aid (LS, lithium stearate), and filler particles (typically 70% fraction by weight). The curing of the filled elastomer parts occurs from the heat-activated reaction between the hydroxyl groups of VCE with the Hylene MP curing agent, resulting in a cross-linked network. The final vinyl acetate content is typically between 34.9 and 37.9%, while the vinyl alcohol content is typically between 1.27 and 1.78%. Surveillance data for this material is both scarce and scattered, complicating the assessment of any aging trends in systems. In addition, most of the initial surveillance efforts focused on mechanical properties such as hardness and tensile strength, and chemical information is therefore lacking. Material characterization and aging studies had been performed on previous formulations of the VCE material but the Ethylene Vinyl Acetate (EVA) starting copolymer is no longer commercially available. New formulations with replacement EVA materials are currently being established and will require characterization as well as updated aging models.

  5. Studies in cutaneous aging: II. The microvasculature

    SciTech Connect

    Braverman, I.M.; Fonferko, E.

    1982-05-01

    Researchers studied by light and electron microscopy the microcirculatory vessels in the sun exposed and sun protected skin of normal and psoriatic individuals in order to separate the features of actinic damage from those of chronological aging. In actinically damaged skin, the vascular walls of postcapillary venules and of arterial and venous capillaries were thickened by the peripheral addition of a layer of basement membrane-like material. The veil cells which were intimately related to these layers often had dilated cisternae of rough endoplasmic reticulum containing electron dense material. In 3 of 8 individuals, 70, 70 and 72 yr old, the buttock skin showed mold vascular wall thickening. In 5 other patients, 59-88 yr old the vessels of the buttock skin were normal. In 4 individuals 80-93 yr old, the vessels were abnormally thin (0.5-1.0 micrometer). The veil cells were either absent or decreased in number in these specimens. Researchers propose that (1) the veil cell is responsible for the synthesis and maintenance of the peripheral portion of the vascular wall of the dermal microcirculatory vessels; (2) the veil cell is stimulated to produce excessive basement membrane-like material in response to UV light, factors associated with diabetes mellitus, and possibly to factors associated with the early phase of chronological aging; and (3) with progressive aging there is a decrease in the number and synthetic activity of veil cells which correlates with the appearance of abnormally thin walled vessels.

  6. Significance of zircon U-Pb ages from the Pescadero felsite, west-central California coast ranges

    USGS Publications Warehouse

    McLaughlin, Robert J.; Moore, Diane E.; ,; Martens, UWE C.; Clark, J.C.

    2011-01-01

    Weathered felsite is associated with the late Campanian–Maastrichtian Pigeon Point Formation near Pescadero, California. Poorly exposed, its age and correlation are uncertain. Is it part of the Pigeon Point section west of the San Gregorio–Hosgri fault? Does it rest on Nacimiento block basement? Is it dextrally offset from the Oligocene Cambria Felsite, ∼185 km to the southeast? Why is a calc-alkaline hypabyssal igneous rock intrusive into the outboard accretionary prism? To address these questions, we analyzed 43 oscillatory-zoned zircon crystals from three incipiently recrystallized pumpellyite ± prehnite ± laumontite-bearing Pescadero felsite samples by sensitive high-resolution ion microprobe–reverse geometry (SHRIMP-RG) and laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) techniques. Thirty-three zircons gave late Mesozoic U-Pb ages, with single-grain values ranging from 81 to 167 Ma; ten have pre-Mesozoic, chiefly Proterozoic ages. A group of the four youngest Pescadero zircons yielded an apparent maximum igneous age of ca. 86–90 Ma. Reflecting broad age scatter and presence of partly digested sandstone inclusions, we interpret the rest of the zircons (perhaps all) as xenocrysts. Twenty-three zircons were separated and analyzed from two samples of the similar Cambria Felsite, yielding a unimodal 27 Ma U-Pb age. Clearly, the origin of the Upper Oligocene Cambria Felsite is different from that of the Upper Cretaceous Pescadero felsite; these rocks are not correlated, and do not constrain displacement along the San Gregorio–Hosgri fault. Peak ages differ slightly, but relative probability curves for Mesozoic and pre-Mesozoic Pescadero zircons compare well, for example, with abundant U-Pb age data for detrital zircons from Franciscan metaclastic strata ∼100 km to the east in the Diablo Range–San Francisco Bay area, San Joaquin Great Valley Group turbidites, Upper Cretaceous Nacimiento block Franciscan strata, and Upper

  7. Studying of tritium content in snowpack of Degelen mountain range.

    PubMed

    Turchenko, D V; Lukashenko, S N; Aidarkhanov, A O; Lyakhova, O N

    2014-06-01

    The paper presents the results of investigation of tritium content in the layers of snow located in the streambeds of the "Degelen" massif contaminated with tritium. The objects of investigation were selected watercourses Karabulak, Uzynbulak, Aktybai located beyond the "Degelen" site. We studied the spatial distribution of tritium relative to the streambed of watercourses and defined the borders of the snow cover contamination. In the centre of the creek watercourses the snow contamination in the surface layer is as high as 40 000 Bq/L. The values of the background levels of tritium in areas not related to the streambed, which range from 40 to 50 Bq/L. The results of snow cover measurements in different seasonal periods were compared. The main mechanisms causing tritium transfer in snow were examined and identified. The most important mechanism of tritium transfer in the streams is tritium emanation from ice or soil surface.

  8. Cohort Profile: The English Longitudinal Study of Ageing

    PubMed Central

    Steptoe, Andrew; Breeze, Elizabeth; Banks, James; Nazroo, James

    2013-01-01

    The English Longitudinal Study of Ageing (ELSA) is a panel study of a representative cohort of men and women living in England aged ≥50 years. It was designed as a sister study to the Health and Retirement Study in the USA and is multidisciplinary in orientation, involving the collection of economic, social, psychological, cognitive, health, biological and genetic data. The study commenced in 2002, and the sample has been followed up every 2 years. Data are collected using computer-assisted personal interviews and self-completion questionnaires, with additional nurse visits for the assessment of biomarkers every 4 years. The original sample consisted of 11 391 members ranging in age from 50 to 100 years. ELSA is harmonized with ageing studies in other countries to facilitate international comparisons, and is linked to financial and health registry data. The data set is openly available to researchers and analysts soon after collection (http://www.esds.ac.uk/longitudinal/access/elsa/l5050.asp). PMID:23143611

  9. Lithofacies, Age, and Sequence Stratigraphy of the Carboniferous Lisburne Group in the Skimo Creek Area, Central Brooks Range

    USGS Publications Warehouse

    Dumoulin, Julie A.; Whalen, Michael T.; Harris, Anita G.

    2008-01-01

    The Lisburne Group, a mainly Carboniferous carbonate succession that is widely distributed across northern Alaska, contains notable amounts of oil and gas at Prudhoe Bay. Detailed studies of the Lisburne in the Skimo Creek area, central Brooks Range, delineate its lithofacies, age, conodont biofacies, depositional environments, and sequence stratigraphy and provide new data on its hydrocarbon source-rock and reservoir potential, as well as its thermal history, in this area. We have studied the Lisburne Group in two thrust sheets of the Endicott Mountains allochthon, herein called the Skimo and Tiglukpuk thrust sheets. The southern, Skimo Creek section, which is >900 m thick, is composed largely of even-bedded to nodular lime mudstone and wackestone intercalated with intervals of thin- to thick-bedded bioclastic packstone and grainstone. Some parts of the section are partially to completely dolomitized and (or) replaced by chert. A distinctive, 30-m-thick zone of black, organic-rich shale, lime mudstone, and phosphorite is exposed 170 m below the top of the Lisburne. The uppermost 40 m of section is also distinctive and made up of dark shale, lime mudstone, spiculite, and glauconitic grainstone. The northern, Tiglukpuk Creek section, which is similar to the Skimo Creek section but only ~760 m thick, includes more packstone and grainstone and less organic-rich shale. Analyses of conodonts and foraminifers indicate that both sections range in age from late Early Mississippian (Osagean) through Early Pennsylvanian (early Morrowan) and document a hiatus of at least 15 m.y. at the contact between the Lisburne and the overlying Siksikpuk Formation. No evidence of subaerial exposure was observed along this contact, which may represent a submarine erosional surface. Lithofacies and biofacies imply that the Lisburne Group in the study area was deposited mainly in midramp to outer-ramp settings. Deepest water strata are mud rich and formed below storm or fair-weather wave

  10. Harvard Aging Brain Study: Dataset and accessibility.

    PubMed

    Dagley, Alexander; LaPoint, Molly; Huijbers, Willem; Hedden, Trey; McLaren, Donald G; Chatwal, Jasmeer P; Papp, Kathryn V; Amariglio, Rebecca E; Blacker, Deborah; Rentz, Dorene M; Johnson, Keith A; Sperling, Reisa A; Schultz, Aaron P

    2017-01-01

    The Harvard Aging Brain Study is sharing its data with the global research community. The longitudinal dataset consists of a 284-subject cohort with the following modalities acquired: demographics, clinical assessment, comprehensive neuropsychological testing, clinical biomarkers, and neuroimaging. To promote more extensive analyses, imaging data was designed to be compatible with other publicly available datasets. A cloud-based system enables access to interested researchers with blinded data available contingent upon completion of a data usage agreement and administrative approval. Data collection is ongoing and currently in its fifth year.

  11. Binary 193nm photomasks aging phenomenon study

    NASA Astrophysics Data System (ADS)

    Dufaye, Félix; Sartelli, Luca; Pogliani, Carlo; Gough, Stuart; Sundermann, Frank; Miyashita, Hiroyuki; Hidenori, Yoshioka; Charras, Nathalie; Brochard, Christophe; Thivolle, Nicolas

    2011-05-01

    193nm binary photomasks are still used in the semiconductor industry for the lithography of some critical layers for the nodes 90nm and 65nm, with high volumes and over long period. These 193nm binary masks seem to be well-known but recent studies have shown surprising degrading effects, like Electric Field induced chromium Migration (EFM) [1] or chromium migration [2] [3] . Phase shift Masks (PSM) or Opaque MoSi On Glass (OMOG) might not be concerned by these effects [4] [6] under certain conditions. In this paper, we will focus our study on two layers gate and metal lines. We will detail the effects of mask aging, with SEM top view pictures revealing a degraded chromium edge profile and TEM chemical analyses demonstrating the growth of a chromium oxide on the sidewall. SEMCD measurements after volume production indicated a modified CD with respect to initial CD data after manufacture. A regression analysis of these CD measurements shows a radial effect, a die effect and an isolated-dense effect. Mask cleaning effectiveness has also been investigated, with sulphate or ozone cleans, to recover the mask quality in terms of CD. In complement, wafer intrafield CD measurements have been performed on the most sensitive structure to monitor the evolution of the aging effect on mask CD uniformity. Mask CD drift have been correlated with exposure dose drift and isolated-dense bias CD drift on wafers. In the end, we will try to propose a physical explanation of this aging phenomenon and a solution to prevent from it occurring.

  12. The fate of cognition in very old age: six-year longitudinal findings in the Berlin Aging Study (BASE).

    PubMed

    Singer, Tania; Verhaeghen, Paul; Ghisletta, Paolo; Lindenberger, Ulman; Baltes, Paul B

    2003-06-01

    The authors report full-information longitudinal age gradients in 4 intellectual abilities on the basis of 6-year longitudinal changes in 132 individuals (mean age at T1 = 78.27, age range = 70-100) from the Berlin Aging Study. Relative to the cross-sectional parent sample (N = 516, mean age at T1 = 84.92 years), this sample was positively selected because of differential mortality and experimental attrition. Perceptual speed, memory, and fluency declined with age. In contrast, knowledge remained stable up to age 90, with evidence for decline thereafter. Age gradients were more negative in old old (n = 66, mean age at T1 = 83.04) than in old (n = 66, mean age at T1 = 73.77) participants. Rates of decline did not differ reliably between men and women or between participants with high versus low life-history status. They conclude that intellectual development after age 70 varies by distance to death, age, and intellectual ability domain.

  13. Chronological Age, Cognitions, and Practices in European American Mothers: A Multivariate Study of Parenting

    ERIC Educational Resources Information Center

    Bornstein, Marc H.; Putnick, Diane L.

    2007-01-01

    The authors studied multiple parenting cognitions and practices in European American mothers (N=262) who ranged from 15 to 47 years of age. All were 1st-time parents of 20-month-old children. Some age effects were 0; others were linear or nonlinear. Nonlinear age effects determined by spline regression showed significant associations to a "knot"…

  14. Cosmogenic 10Be and 26Al exposure ages of glaciations in the Frankland Range, southwest Tasmania reveal a limited MIS-2 ice advance

    NASA Astrophysics Data System (ADS)

    Kiernan, Kevin; Fink, David; McConnell, Anne

    2017-02-01

    New mapping of the glacial geomorphology coupled with 10Be and 26Al exposure age dating of moraines on the flanks of the Frankland Range in south west Tasmania indicate that glacier extent during MIS-2 was far smaller than during earlier glaciations with the ice cover being confined to only the uppermost cirques of the range. Moraines further down the range flanks, ∼50-150 m lower in altitude than the MIS-2 dated advance, indicate that glaciers were only slightly larger during earlier glaciations and, depending on the interpretation of their exposure ages, may range from MIS 7 to MIS 12. These older moraines are nested inside the maximum ice limits of an even more ancient and extensive glaciation, defined by degraded valley floor moraines and coalescing glacio-fluvial fans that remain undated but appear no younger than MIS 12. Patterns of glacial erosion and moraine deposition on the Frankland Range suggest that the more recent glaciations were increasingly influenced by the erosional morphology initiated by earlier glaciers. Microclimatic differences resulting from this earlier glacial topography were particularly influential determinants of glaciation during MIS 2. These results are consistent with emerging evidence from studies of other ranges in southwest Tasmania.

  15. Thermal ageing and short-range ordering of Alloy 690 between 350 and 550 °C

    NASA Astrophysics Data System (ADS)

    Mouginot, Roman; Sarikka, Teemu; Heikkilä, Mikko; Ivanchenko, Mykola; Ehrnstén, Ulla; Kim, Young Suk; Kim, Sung Soo; Hänninen, Hannu

    2017-03-01

    Thermal ageing of Alloy 690 triggers an intergranular (IG) carbide precipitation and is known to promote an ordering reaction causing lattice contraction. It may affect the long-term primary water stress corrosion cracking (PWSCC) resistance of pressurized water reactor (PWR) components. Four conditions of Alloy 690 (solution annealed, cold-rolled and/or heat-treated) were aged between 350 and 550 °C for 10 000 h and characterized. Although no direct observation of ordering was made, variations in hardness and lattice parameter were attributed to the formation of short-range ordering (SRO) in all conditions with a peak level at 420 °C, consistent with the literature. Prior heat treatment induced ordering before thermal ageing. At higher temperatures, stress relaxation, recrystallization and α-Cr precipitation were observed in the cold-worked samples, while a disordering reaction was inferred in all samples based on a decrease in hardness. IG precipitation of M23C6 carbides increased with increasing ageing temperature in all conditions, as well as diffusion-induced grain boundary migration (DIGM).

  16. Wide range modeling study of dimethyl ether oxidation

    SciTech Connect

    Pitz, W.J.; Marinov, N.M.; Westbrook, C.K.; Dagaut, P.; Boettner, J-C; Cathonnet, M.

    1997-04-01

    A detailed chemical kinetic model has been used to study dimethyl ether (DME) oxidation over a wide range of conditions. Experimental results obtained in a jet-stirred reactor (JSR) at I and 10 atm, 0.2 < 0 < 2.5, and 800 < T < 1300 K were modeled, in addition to those generated in a shock tube at 13 and 40 bar, 0 = 1.0 and 650 :5 T :5 1300 K. The JSR results are particularly valuable as they include concentration profiles of reactants, intermediates and products pertinent to the oxidation of DME. These data test the Idnetic model severely, as it must be able to predict the correct distribution and concentrations of intermediate and final products formed in the oxidation process. Additionally, the shock tube results are very useful, as they were taken at low temperatures and at high pressures, and thus undergo negative temperature dependence (NTC) behavior. This behavior is characteristic of the oxidation of saturated hydrocarbon fuels, (e.g. the primary reference fuels, n-heptane and iso- octane) under similar conditions. The numerical model consists of 78 chemical species and 336 chemical reactions. The thermodynamic properties of unknown species pertaining to DME oxidation were calculated using THERM.

  17. Dental age estimation using Willems method: A digital orthopantomographic study

    PubMed Central

    Mohammed, Rezwana Begum; Krishnamraju, P. V.; Prasanth, P. S.; Sanghvi, Praveen; Lata Reddy, M. Asha; Jyotsna, S.

    2014-01-01

    In recent years, age estimation has become increasingly important in living people for a variety of reasons, including identifying criminal and legal responsibility, and for many other social events such as a birth certificate, marriage, beginning a job, joining the army, and retirement. Objectives: The aim of this study was to assess the developmental stages of left seven mandibular teeth for estimation of dental age (DA) in different age groups and to evaluate the possible correlation between DA and chronological age (CA) in South Indian population using Willems method. Materials and Methods: Digital Orthopantomogram of 332 subjects (166 males, 166 females) who fit the study and the criteria were obtained. Assessment of mandibular teeth (from central incisor to the second molar on left quadrant) development was undertaken and DA was assessed using Willems method. Results and Discussion: The present study showed a significant correlation between DA and CA in both males (r = 0.71 and females (r = 0.88). The overall mean difference between the estimated DA and CA for males was 0.69 ± 2.14 years (P < 0.001) while for females, it was 0.08 ± 1.34 years (P > 0.05). Willems method underestimated the mean age of males by 0.69 years and females by 0.08 years and showed that females mature earlier than males in selected population. The mean difference between DA and CA according to Willems method was 0.39 years and is statistically significant (P < 0.05). Conclusion: This study showed significant relation between DA and CA. Thus, digital radiographic assessment of mandibular teeth development can be used to generate mean DA using Willems method and also the estimated age range for an individual of unknown CA. PMID:25191076

  18. Neuropathologic Studies of the Baltimore Longitudinal Study of Aging (BLSA)

    PubMed Central

    O’Brien, Richard J.; Resnick, Susan M.; Zonderman, Alan B.; Ferrucci, Luigi; Crain, Barbara J.; Pletnikova, Olga; Rudow, Gay; Iacono, Diego; Riudavets, Miguel A.; Driscoll, Ira; Price, Donald L.; Martin, Lee J.; Troncoso, Juan C.

    2010-01-01

    The Baltimore Longitudinal Study of Aging (BLSA) was established in 1958 and is one the oldest prospective studies of aging in the USA and the world. The BLSA is supported by the National Institute of Aging (NIA) and its mission is to learn what happens to people as they get old and how to sort out changes due to aging and from those due to disease or other causes. In 1986, an autopsy program combined with comprehensive neurologic and cognitive evaluations was established in collaboration with the Johns Hopkins University Alzheimer’s Disease Research Center (ADRC). Since then, 211 subjects have undergone autopsy. Here we review the key clinical neuropathological correlations from this autopsy series. The focus is on the morphological and biochemical changes that occur in normal aging, and the early neuropathological changes of neurodegenerative diseases, especially Alzheimer’s disease (AD). We highlight the combined clinical, pathologic, morphometric, and biochemical evidence of asymptomatic AD, a state characterized by normal clinical evaluations in subjects with abundant AD pathology. We conclude that in some individuals, successful cognitive aging results from compensatory mechanisms that occur at the neuronal level (i.e., neuronal hypertrophy and synaptic plasticity) whereas a failure of compensation may culminate in disease. PMID:19661626

  19. Aging

    PubMed Central

    Park, Dong Choon

    2013-01-01

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

  20. Long-range eye tracking: A feasibility study

    SciTech Connect

    Jayaweera, S.K.; Lu, Shin-yee

    1994-08-24

    The design considerations for a long-range Purkinje effects based video tracking system using current technology is presented. Past work, current experiments, and future directions are thoroughly discussed, with an emphasis on digital signal processing techniques and obstacles. It has been determined that while a robust, efficient, long-range, and non-invasive eye tracking system will be difficult to develop, such as a project is indeed feasible.

  1. Long-range transport of black carbon to the Pacific Ocean and its dependence on aging timescale

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Liu, J.; Tao, S.; Ban-Weiss, G. A.

    2015-06-01

    Improving the ability of global models to predict concentrations of black carbon (BC) over the Pacific Ocean is essential to evaluate the impact of BC on marine climate. In this study, we tag BC tracers from 13 source regions around the globe in a global chemical transport model MOZART-4. Numerous sensitivity simulations are carried out varying the aging timescale of BC emitted from each source region. The aging timescale for each source region is optimized by minimizing errors in vertical profiles of BC mass mixing ratios between simulations and HIAPER Pole-to-Pole Observations (HIPPO). For most HIPPO deployments, in the Northern Hemisphere, optimized aging timescales are less than half a day for BC emitted from tropical and mid-latitude source regions, and about 1 week for BC emitted from high latitude regions in all seasons except summer. We find that East Asian emissions contribute most to the BC loading over the North Pacific, while South American, African and Australian emissions dominate BC loadings over the South Pacific. Dominant source regions contributing to BC loadings in other parts of the globe are also assessed. The lifetime of BC originating from East Asia (i.e., the world's largest BC emitter) is found to be only 2.2 days, much shorter than the global average lifetime of 4.9 days, making East Asia's contribution to global burden only 36 % of BC from the second largest emitter, Africa. Thus, evaluating only relative emission rates without accounting for differences in aging timescales and deposition rates is not predictive of the contribution of a given source region to climate impacts. Our simulations indicate that lifetime of BC increases nearly linearly with aging timescale for all source regions. When aging rate is fast, the lifetime of BC is largely determined by factors that control local deposition rates (e.g. precipitation). The sensitivity of lifetime to aging timescale depends strongly on the initial hygroscopicity of freshly emitted BC

  2. Long-range transport of black carbon to the Pacific Ocean and its dependence on aging timescale

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Liu, J.; Tao, S.; Ban-Weiss, G. A.

    2015-10-01

    Improving the ability of global models to predict concentrations of black carbon (BC) over the Pacific Ocean is essential to evaluate the impact of BC on marine climate. In this study, we tag BC tracers from 13 source regions around the globe in a global chemical transport model, Model for Ozone and Related Chemical Tracers, version 4 (MOZART-4). Numerous sensitivity simulations are carried out varying the aging timescale of BC emitted from each source region. The aging timescale for each source region is optimized by minimizing errors in vertical profiles of BC mass mixing ratios between simulations and HIAPER Pole-to-Pole Observations (HIPPO). For most HIPPO deployments, in the Northern Hemisphere, optimized aging timescales are less than half a day for BC emitted from tropical and midlatitude source regions and about 1 week for BC emitted from high-latitude regions in all seasons except summer. We find that East Asian emissions contribute most to the BC loading over the North Pacific, while South American, African and Australian emissions dominate BC loadings over the South Pacific. Dominant source regions contributing to BC loadings in other parts of the globe are also assessed. The lifetime of BC originating from East Asia (i.e., the world's largest BC emitter) is found to be only 2.2 days, much shorter than the global average lifetime of 4.9 days, making the contribution from East Asia to the global BC burden only 36 % of that from the second largest emitter, Africa. Thus, evaluating only relative emission rates without accounting for differences in aging timescales and deposition rates is not predictive of the contribution of a given source region to climate impacts. Our simulations indicate that the lifetime of BC increases nearly linearly with aging timescale for all source regions. When the aging rate is fast, the lifetime of BC is largely determined by factors that control local deposition rates (e.g., precipitation). The sensitivity of lifetime to aging

  3. A comparative study of beef quality after ageing longissimus muscle using a dry ageing bag, traditional dry ageing or vacuum package ageing.

    PubMed

    Li, Xin; Babol, Jakub; Bredie, Wender L P; Nielsen, Belinda; Tománková, Jana; Lundström, Kerstin

    2014-08-01

    The objective of this study was to investigate beef quality of longissimus muscle after ageing in dry ageing bags, traditional dry ageing or vacuum for 8 or 19 days. Lower ageing weight loss, odour score and microbial growth were found in meat aged in dry ageing bags than after traditional dry ageing. The sensory panel detected no differences for most of the sensory attributes between samples using the two dry ageing methods, except for the odour of the cutting surface. The dry-aged steaks had more umami and butter fried meat taste compared with vacuum-aged steaks. Ageing time affected most of the sensory traits in this study, which improved as ageing time increased from 8 to 19 days. In a consumer test, meat aged for 21 days in dry ageing bags was preferred than the samples aged in vacuum. This may be due to the higher tenderness and juiciness obtained during storage in dry ageing bags than meat aged in vacuum.

  4. Predicting the Remaining Lifespan and Cultivation-Related Loss of Osteogenic Capacity of Bone Marrow Multipotential Stromal Cells Applicable across a Broad Donor Age Range

    PubMed Central

    Churchman, Sarah M.; Boxall, Sally A.; McGonagle, Dennis

    2017-01-01

    Background and Objectives. Culture expanded multipotential stromal cells (MSCs) have considerable potential for bone regeneration therapy but their wider use is constrained by the lack of simple and predictive assays of functional potency. Extended passaging leads to loss of multipotency but speed of decline depends on MSC donor age. The aim of this study was to develop an assay predictive of MSC culture longevity applicable to a broad donor age range. Materials and Methods. Bone marrow (BM, n = 7) was obtained from a diverse range (2–72 years) of healthy donors. MSCs were culture expanded to senescence and their osteoprogenitor content, gene expression profiles, epigenetic signature, and telomere behaviour were measured throughout. Output data was combined for modelling purposes. Results. Regardless of donor age, cultures' osteoprogenitor content correlated better with remaining lifespan (population doublings before senescence, PD-BS) than proliferative history (accrued PDs). Individual gene's expression or telomere length did not predict PD-BS but methylation of individual CpG islands did, PRAMEF2 in particular (r = 0.775). Coupling the steep relationship of relative SPARC expression with PD-BS (r = −0.753) the formula SPARC × 1/PREMEF2 gave an improved correlation (r = −0.893). Conclusion. A formula based on SPARC mRNA and PRAMEF2 methylation may be used to predict remaining BM-MSC longevity and related loss of multipotentiality independent of donor age. PMID:28298930

  5. Looking Beyond Chronological Age: Current Knowledge and Future Directions in the Study of Subjective Age.

    PubMed

    Kotter-Grühn, Dana; Kornadt, Anna E; Stephan, Yannick

    2015-01-01

    The notion of the heterogeneity of aging goes along with the awareness that every person experiences aging differently. Over the past years, scholars have emphasized that the assessment of these subjective experiences of aging contributes to our understanding of a range of psychological and physiological processes and outcomes among older adults. One construct frequently used in this context is subjective age, that is, how old or young a person feels. Subjective age has been shown to be an important correlate as well as a predictor of markers of successful aging such as well-being, health, and longevity. However, less is known about the antecedents of subjective age and the mechanisms underlying the relationship between feeling younger and positive developmental outcomes. This article briefly summarizes and critically evaluates the empirical evidence on this topic and makes suggestions on how to address and potentially overcome currently existing theoretical, methodological, and psychometric challenges. Based on the discussion of these challenges, the paper provides directions for future research by outlining underexplored topics such as intraindividual variability and determinants of subjective age, the match between objective age indicators and subjective age, and how subjective age maps on behavior and functioning.

  6. {alpha}/{beta} ratio: A dose range dependence study

    SciTech Connect

    Garcia, Lourdes M. . E-mail: logarcia@ottawahospital.on.ca; Wilkins, David E.; Raaphorst, Gijsbert P.

    2007-02-01

    Purpose: To investigate the dependence of the {alpha}/{beta} ratio determined from in vitro survival curves on the dose ranges. Methods: Detailed clonogenic cell survival experiments were used to determine the least squares estimators for the linear quadratic model for different dose ranges. The cell lines used were CHO AA8, a Chinese hamster fibroblast cell line; U-373 MG, a human glioblastoma cell line; and CP3 and DU-145, two human prostate carcinoma cell lines. The {alpha}, {beta}, and {alpha}/{beta} ratio behaviors, combined with a goodness-of-fit analysis and Monte Carlo simulation of the experiments, were assessed within different dose regions. Results: Including data from the low-dose region has a significant influence on the determination of the {alpha}, {beta}, and {alpha}/{beta} ratio from in vitro survival curve data. In this region, the values are poorly determined and have significant variability. The mid-dose region is characterized by more precise and stable values and is in agreement with the linear quadratic model. The high-dose region shows relatively small statistical error in the fitted parameters but the goodness-of-fit and Monte Carlo analyses showed poor quality fits. Conclusion: The dependence of the fitted {alpha} and {beta} on the dose range has an impact on the {alpha}/{beta} ratio determined from the survival data. The low-dose region had a significant influence that could be a result of a strong linear, rather than quadratic, component, hypersensitivity, and adaptive responses. This dose dependence should be interpreted as a caution against using inadequate in vitro cell survival data for {alpha}/{beta} ratio determination.

  7. Concept definition study for an extremely large aerophysics range facility

    NASA Technical Reports Server (NTRS)

    Swift, Hallock F.

    1993-01-01

    A conceptual design of a very large aeroballistic range is presented, as are its operational characteristics and procedures. The proposed model launcher is a two-stage light-gas gun, having a launch tube diameter of 254 mm, and the capability of accelerating a 14 kg launch mass to 6.1 km/sec. The gun's 91.4 cm diameter piston is driven by pressurized helium. High pressures in the central breech are contained by a multiple disk arrangement. The blast tank and sabot separation tank are described, as are methods for arresting sabot segments. The conceptual design of the range itself includes a 3.3 m diameter test or flight chamber some 330 m in length. Provisions are made for testing of free flight models and tests in which the model is confined by a track system. Methods for model deceleration and recovery are described. Provisions required for future addition of advanced model launchers such as an electromagnetic launcher or ram accelerator are addressed. Siting and safety issues are also addressed.

  8. X-Ray Exam: Bone Age Study (For Parents)

    MedlinePlus

    ... 2-Year-Old X-Ray Exam: Bone Age Study KidsHealth > For Parents > X-Ray Exam: Bone Age Study A A A What's in this article? What ... edad ósea What It Is A bone age study helps doctors estimate the maturity of a child's ...

  9. X-Ray Exam: Bone Age Study (For Parents)

    MedlinePlus

    ... to 2-Year-Old X-Ray Exam: Bone Age Study KidsHealth > For Parents > X-Ray Exam: Bone Age Study Print A A A What's in this ... la edad ósea What It Is A bone age study helps doctors estimate the maturity of a ...

  10. Reference Ranges and Association of Age and Lifestyle Characteristics with Testosterone, Sex Hormone Binding Globulin, and Luteinizing Hormone among 1166 Western Chinese Men

    PubMed Central

    Shen, Xubo; Wang, Ruifeng; Yu, Na; Shi, Yongjun; Li, Honggang; Xiong, Chengliang; Li, Yan; Zhou, Yuanzhong

    2016-01-01

    Decreased total testosterone (TT) is the recommended metric to identify age-related hypogonadism. However, average TT and the extent to which it varies by age, can vary substantially among different populations. Population-specific reference ranges are needed to understand normal versus abnormal TT levels. Therefore, the goal for this study was to describe androgen concentrations and their correlates among Western Chinese men. We completed a population-based, cross-sectional study including 227 young adults (YA) (20–39 years) and 939 older adults (OA) (40–89 years). We measured TT, sex-hormone binding globulin (SHBG), luteinizing hormone (LH), testosterone secreting index (TSI), and calculated free testosterone (cFT). Reference ranges for this population were determined using average YA concentrations. Multivariable regression models were used to predict hormone concentrations adjusting for age, waist-to-height ratio (WHR), marital status, education, occupation, smoking, alcohol, blood glucose, and blood pressure. Among OA, 3.8% had low TT, 15.2% had low cFT, 26.3% had low TSI, 21.6% had high SHBG, and 6.1% had high LH. Average cFT was significantly lower in OA (0.30 nmol/L; standard deviation (SD): 0.09) versus YA (0.37; SD: 0.11) but TT was not different in OA (16.82 nmol/L; SD: 4.80) versus YA (16.88; SD: 5.29). In adjusted models increasing age was significantly associated with increased SHBG or LH, and decreased cFT or TSI; however, TT was not significantly associated with age (β = 0.02 nmol/L; 95% confidence interval (CI): -0.01, 0.04). Higher WHR was associated with significantly decreased TT, SHBG, TSI, and LH. The only variable significantly related to cFT was age (β = -0.0033; 95% CI:-0.0037, -0.0028); suggesting that cFT measurements would not be confounded by other lifestyle factors. In conclusion, cFT, but not TT, varies with age in this population, suggesting cFT may be a better potential marker for age-related androgen deficiency than TT among

  11. A Quiet Standing Index for Testing the Postural Sway of Healthy and Diabetic Adults Across a Range of Ages

    PubMed Central

    Bollt, Erik M.; Fulk, George D.; Skufca, Joseph D.; Al-Ajlouni, Ahmad F.; Robinson, Charles J.

    2010-01-01

    A quietstanding index is developed for tracking the postural sway of healthy and diabetic adults over a range of ages. Several postural sway features are combined into a single composite feature C that increases with age a. Sway features are ranked based on the r2 -values of their linear regression models, and the composite feature is a weighted sum of selected sway features with optimal weighting coefficients determined using principal component analysis. A performance index based on both reliability and sensitivity is used to determine the optimal number of features. The features used to form C include power and distance metrics. The quiet standing index is a scalar that compares the composite feature C to a linear regression model f (a) using C′ (a) = C/f (a). For a motionless subject, C′ = 0, and when the composite feature exactly matches the healthy control (HC) model, C′ = 1. Values of C′ ≫ 1 represent excessive postural sway and may indicate impaired postural control. Diabetic neurologically intact subjects, nondiabetic peripheral neuropathy subjects (PN), and diabetic PN subjects (DPN) were evaluated. The quiet standing indexes of the PN and DPN groups showed statistically significant increases over the HC group. Changes in the quiet standing index over time may be useful in identifying people with impaired balance who may be at an increased risk of falling. PMID:19342327

  12. Age Identification in the Framework of Successful Aging: A Study of Older Finnish People

    ERIC Educational Resources Information Center

    Uotinen, Virpi; Suutama, Timo; Ruoppila, Isto

    2003-01-01

    A person-oriented approach was used in a study of age identification among community-dwelling older people. The study was based on 8-year follow-up data; 843 persons aged 65-84 were involved in the first phase of the study, and 426 persons aged 73-92, in the second phase. Loosely, on the basis of the distinction between successful, usual, and…

  13. Women's preferences for masculinity in male faces are highest during reproductive age range and lower around puberty and post-menopause.

    PubMed

    Little, Anthony C; Saxton, Tamsin K; Roberts, S Craig; Jones, Benedict C; Debruine, Lisa M; Vukovic, Jovana; Perrett, David I; Feinberg, David R; Chenore, Todd

    2010-07-01

    Masculinity in male faces is thought to be a sign of mate quality and is associated with measures of long-term health. Previous studies have demonstrated that women's masculinity preferences change across the menstrual cycle with women preferring more masculine men during phases of the menstrual cycle where fertility is highest (i.e. the late follicular phase). Given the hormonal correlates of such preferences and that these hormones change across the life span, we tested for differences in female masculinity preferences at different ages. We compared the masculinity preferences of peri-pubescent girls and young adult women (Study 1), circum-menopausal women reporting to either be pre- or post-menopause (Study 2), and a large sample of women across a wide range of ages (Study 3). In all three studies, preferences for masculinity in male faces were highest in women who were at a reproductively active age. Preferences for masculinity were lower when females were peri-pubescent, post-menopausal, or at ages corresponding to these groups. These data support the notion that masculinity in male faces is an important trait for reproductively relevant mate choice decisions. These data also highlight a shift in female visual preferences for men that is associated with important stages of the lifespan. Visual preferences appear to track important hormonal changes associated with age; as women pass puberty their preferences shift towards facial traits associated with mate quality and as women undergo menopause their preferences for such facial traits decrease. Overall, these results demonstrate the important role of reproductive status and support the notion that preferences for male faces are tied to reproductively relevant hormones.

  14. Radar Cross Section Studies/Compact Range Research

    NASA Technical Reports Server (NTRS)

    Burnside, W. D.; Dominek, A. K.; Gupta, I. J.; Newman, E. H.; Pathak, P. H.; Peters, L., Jr.

    1988-01-01

    A summary is given of the achievements of NASA Grant NsG-1613 by Ohio State University from May 1, 1987 to April 30, 1988. The major topics covered are as follows: (1) electromagnetic scattering analysis; (2) indoor scattering measurement systems; (3) RCS control; (4) waveform processing techniques; (5) material scattering and design studies; (6) design and evaluation of design studies; and (7) antenna studies. Major progress has been made in each of these areas as verified by the numerous publications produced.

  15. Radar cross section studies/compact range research

    NASA Technical Reports Server (NTRS)

    Burnside, W. D.; Dominek, A. K.; Gupta, I. J.; Newman, E. H.; Pathak, P. H.; Peters, L., Jr.

    1989-01-01

    Achievements in advancing the state-of-the-art in the measurement, control, and analysis of electromagnetic scattering from general aerodynamic targets are summarized. The major topics associated with this study include: (1) electromagnetic scattering analysis; (2) indoor scattering measurement systems; (3) RCS control; (4) waveform processing techniques; (5) material scattering and design studies; (6) design and evaluation of standard targets; and (7) antenna studies. Progress in each of these areas is reported and related publications are listed.

  16. Effect of age at the beginning of the free-range fattening period on growth and carcass and fat quality in Iberian pigs.

    PubMed

    Daza, Argimiro; López-Bote, Clemente; Rey, Ana; Olivares, Alvaro

    2006-08-01

    This experiment was carried out to study the influence of age at the beginning of the free-range fattening period (traditional pigs, TP, age 12 months vs. young pigs, YP, age 8 months) on the performance of Iberian pigs. During 152 days prior to the fattening period, TP and YP pigs received 1.7 and 2.6 kg feed per day, respectively. During fattening, TP pigs had a higher average daily gain (p < 0.05) than YP pigs. The proportions of PUFA and n-3 fatty acids of the outer and inner layers of subcutaneous backfat were higher in TP than in YP pigs (p < 0.05), while the proportions of C16:0 and SFA in the inner layer of subcutaneous backfat were greater in YP than in TP pigs (p < 0.05). The ratio of n-6/n-3 in subcutaneous backfat was lower in TP than in YP pigs (p < 0.05). The percentage of intramuscular fat in longissimus dorsi muscle was higher in TP than in YP pigs (p < 0.05). The relationship between the percentage of intramuscular fat in longissimus dorsi muscle and average daily gain during the free-range fattening period adjusted to a quadratic function (p < 0.05). The concentration of alpha- and gamma-tocopherol in subcutaneous backfat at slaughter was significantly higher in TP than in YP pigs (p < 0.05). It is concluded that Iberian pigs that have 8 months of age at the beginning of free-range feeding have adequate commercial quality.

  17. Late glacial 10Be ages for glacial landforms in the upper region of the Taibai glaciation in the Qinling Mountain range, China

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Liu, Liang; Chen, Yixin; Liu, Beibei; Harbor, Jonathan M.; Cui, Zhijiu; Liu, Rui; Liu, Xiao; Zhao, Xu

    2016-01-01

    Glacial landforms are well preserved on Taibai Mountain (3767 m), the main peak of the Qinling mountain range located south of the Loess Plateau and east of the Qinghai-Tibet Plateau. The timing and extent of Quaternary glaciation in the study area is important for reconstructing Quaternary environmental change however numerical ages for glaciation in this study area have not previously been well resolved. Using terrestrial in situ cosmogenic nuclides we dated four samples collected from two glacially eroded rock steps in the upper part of a valley near the main peak, in an area previously identified as having been occupied by ice during the Taibai glaciation. The 10Be results are all late glacial in age: 18.6 ± 1.1 ka, 16.9 ± 1.0 ka, 16.9 ± 1.1 ka and 15.1 ± 1.0 ka. The spatial pattern of ages in the valley suggests fast retreat, with horizontal and vertical retreat rates estimated to be on the order of 0.4 and 0.09 m a-1, respectively. A simple extrapolation of these retreat rates from the ages at the two sample sites suggests that the glacier retreat began during Last Glacial Maximum and that glaciers disappeared from the main peak by about 15 ka.

  18. Pharmacokinetics of theophylline: a dose-range study.

    PubMed Central

    Rovei, V; Chanoine, F; Strolin Benedetti, M

    1982-01-01

    1 Pharmacokinetics of theophylline were investigated in a group of healthy adult volunteers (non smokers and on xanthine-free diet) following single oral administration of 125, 250, 375 and 500 mg doses as tablets (Theodel). 2 Absorption of theophylline was rapid and followed first-order kinetics. Plasma curves were fitted according to a one compartment open model. 3 There was a linear relationship (P less than 0.001) between plasma Cmax or AUCx values and the administered dose. The analysis of variance showed that the pharmacokinetic parameters of theophylline (t1/2 abs, tmax, t1/2 beta, CL, CLR, Vd and F) were not modified at any dose. 4 Absorption of the drug was complete since the recovery in urine of theophylline (13.7 to 16.8% of the dose) and its major metabolites, 1,3-dimethyluric acid (35 to 42%), 1-methyluric acid (21.3 to 26.7%) and 3-methylxanthine (11.5 to 13.7%), accounted for the administered dose. Some impairment of demethylation to 3-methylxanthine was observed in two subjects, however the percentage of theophylline and its major metabolites excreted in urine was constant for all the four doses. 5 On the basis of these results, after single oral administration, elimination of theophylline followed first-order kinetics in the range of doses investigated (1.62 to 10.42 mg/kg). PMID:7150456

  19. Molecular pathology endpoints useful for aging studies.

    PubMed

    Niedernhofer, L J; Kirkland, J L; Ladiges, W

    2016-10-06

    The first clinical trial aimed at targeting fundamental processes of aging will soon be launched (TAME: Targeting Aging with Metformin). In its wake is a robust pipeline of therapeutic interventions that have been demonstrated to extend lifespan or healthspan of preclinical models, including rapalogs, antioxidants, anti-inflammatory agents, and senolytics. This ensures that if the TAME trial is successful, numerous additional clinical trials are apt to follow. But a significant impediment to these trials remains the question of what endpoints should be measured? The design of the TAME trial very cleverly skirts around this based on the fact that there are decades of data on metformin in humans, providing unequaled clarity of what endpoints are most likely to yield a positive outcome. But for a new chemical entity, knowing what endpoints to measure remains a formidable challenge. For economy's sake, and to achieve results in a reasonable time frame, surrogate markers of lifespan and healthy aging are desperately needed. This review provides a comprehensive analysis of molecular endpoints that are currently being used as indices of age-related phenomena (e.g., morbidity, frailty, mortality) and proposes an approach for validating and prioritizing these endpoints.

  20. Aging Issues in Social Studies Textbooks.

    ERIC Educational Resources Information Center

    Fleming, Dan B.; McAuley, William J.

    1987-01-01

    Examined the treatment of Social Security, civil rights, political power, and population trends in 19 secondary schools' United States history and government textbooks. Found that only Social Security was given adequate treatment. Concluded that the coverage of aging issues in secondary textbooks was generally weak and insufficient. (Author/NB)

  1. The influence of age, gender, lifestyle factors and sub-clinical neck pain on the cervical flexion-rotation test and cervical range of motion.

    PubMed

    Smith, Kenric; Hall, Toby; Robinson, Kim

    2008-12-01

    The flexion-rotation test (FRT) is commonly used when assessing cervicogenic headache. Additionally, active range of motion (AROM) is frequently used to evaluate impairment in neck pain. No studies have investigated the interaction of the FRT and AROM with age, gender, pain and lifestyle factors. The purpose of this study was to determine the influence of these factors on the FRT and cervical AROM. A group of 66 participants (aged 20-78) were studied, 28 experienced sub-clinical neck pain (recurrent neck pain or discomfort which has not received treatment from a healthcare professional) while 38 did not. Age, gender, lifestyle factors and sub-clinical neck pain were assessed using a questionnaire. Measurement of AROM was performed by two examiners blind to the results of the questionnaire. Multiple linear regression analysis found that 59% of the variance in the FRT was explained by the presence of sub-clinical pain and cervical lateral flexion measures. Secondly, 58-72% of the variance in active cervical ROM measures was influenced by factors including the FRT, gender and movements of the neck in other planes. This study found that lifestyle factors do not influence the cervical FRT and AROM.

  2. Pad A Treatability Study long-range project plan

    SciTech Connect

    Mousseau, J.D.

    1991-08-01

    The purpose of the Pad A Treatability Study Project is to identify and demonstrate through lab- and pilot-scale testing, technologies for treating plutonium-contaminated salt waste. This document presents proposed objectives and schedules, scope of work and breakdown structure, cost elements, deployment, benefits, and change controls for the project.

  3. Protein dynamics in a broad frequency range: Dielectric spectroscopy studies

    SciTech Connect

    Nakanishi, Masahiro; Sokolov, Alexei P.

    2014-09-17

    We present detailed dielectric spectroscopy studies of dynamics in two hydrated proteins, lysozyme and myoglobin. We emphasize the importance of explicit account for possible Maxwell-Wagner (MW) polarization effects in protein powder samples. Combining our data with earlier literature results, we demonstrate the existence of three major relaxation processes in globular proteins. To understand the mechanisms of these relaxations we involve literature data on neutron scattering, simulations and NMR studies. The faster process is ascribed to coupled protein-hydration water motions and has relaxation time similar to 10-50 Ps at room temperature. The intermediate process is similar to 10(2)-10(3) times slower than the faster process and might be strongly affected by MW polarizations. Based on the analysis of data obtained by different experimental techniques and simulations, we ascribe this process to large scale domain-like motions of proteins. The slowest observed process is similar to 10(6)-10(7) times slower than the faster process and has anomalously large dielectric amplitude Delta epsilon similar to 10(2)-10(4). The microscopic nature of this process is not clear, but it seems to be related to the glass transition of hydrated proteins. The presentedresults suggest a general classification of the relaxation processes in hydrated proteins. (c) 2014 Elsevier B.V. All rights reserved.

  4. Protein dynamics in a broad frequency range: Dielectric spectroscopy studies

    DOE PAGES

    Nakanishi, Masahiro; Sokolov, Alexei P.

    2014-09-17

    We present detailed dielectric spectroscopy studies of dynamics in two hydrated proteins, lysozyme and myoglobin. We emphasize the importance of explicit account for possible Maxwell-Wagner (MW) polarization effects in protein powder samples. Combining our data with earlier literature results, we demonstrate the existence of three major relaxation processes in globular proteins. To understand the mechanisms of these relaxations we involve literature data on neutron scattering, simulations and NMR studies. The faster process is ascribed to coupled protein-hydration water motions and has relaxation time similar to 10-50 Ps at room temperature. The intermediate process is similar to 10(2)-10(3) times slower thanmore » the faster process and might be strongly affected by MW polarizations. Based on the analysis of data obtained by different experimental techniques and simulations, we ascribe this process to large scale domain-like motions of proteins. The slowest observed process is similar to 10(6)-10(7) times slower than the faster process and has anomalously large dielectric amplitude Delta epsilon similar to 10(2)-10(4). The microscopic nature of this process is not clear, but it seems to be related to the glass transition of hydrated proteins. The presentedresults suggest a general classification of the relaxation processes in hydrated proteins. (c) 2014 Elsevier B.V. All rights reserved.« less

  5. A dose-ranging study of MF59®-adjuvanted and non-adjuvanted A/H1N1 pandemic influenza vaccine in young to middle-aged and older adult populations to assess safety, immunogenicity, and antibody persistence one year after vaccination

    PubMed Central

    Reisinger, Keith S; Holmes, Sandra J; Pedotti, Paola; Arora, Ashwani Kumar; Lattanzi, Maria

    2014-01-01

    Background During development of an A/H1N1 pandemic influenza vaccine, this study was performed to identify the antigen and adjuvant content which would provide optimal antibody response and persistence in adults and the elderly. Dose-sparing strategies, such as inclusion of adjuvants, are critical in ensuring the widest possible population coverage in the event of an influenza pandemic, despite a limited global capacity for vaccine manufacture. Methods Healthy subjects aged 18−64 years (n = 1240) and ≥65 years (n = 1352) were vaccinated with 1 of 8 investigational vaccine formulations varying in antigen quantity (3.75 µg to 30 µg of hemagglutinin) and MF59® adjuvant (none, half dose, or full dose). All subjects received 2 vaccine doses administered 3 weeks apart. Antibody response was assessed by hemagglutination inhibition assay 1 and 3 weeks after administration of first and second doses. Antibody persistence was assessed after 6 and 12 mo. Vaccine safety was monitored over 12 mo. Results All 8 investigational A/H1N1 vaccine formulations were well tolerated, and rapidly induced high antibody titers which met all of the Center for Biologics Evaluation and Research (CBER) and Committee for Medicinal Products for Human Use (CHMP) licensure criteria 3 weeks after one dose. The highest antibody titers were observed in participants vaccinated with higher quantities of antigen and adjuvant. Conclusion A single vaccine dose containing 3.75 µg of A/California/7/2009 (H1N1) antigen with MF59 adjuvant was identified as optimal for young to middle-aged (18−64 years) and older (≥65 years) adult populations. PMID:25424947

  6. A twin study on age-related macular degeneration.

    PubMed Central

    Meyers, S M

    1994-01-01

    A prospective twin study on age-related macular degeneration (AMD) recruited 83 monozygotic pairs, 28 dizygotic pairs, and one triplet set from 1986 through 1993. Zygosity was determined by genetic testing of red cell markers, HLA antigens, or specific DNA loci. There were no twin pairs in which I collected data on only one twin. To decrease ascertainment bias, after 1991 the recruitment notice did not mention AMD, and I did not ask about a history of eye disease before the eye examination. Because of this, twin pairs recruited from 1986 through 1991 were statistically analyzed separately from those after January 1, 1992. From 1986 through 1991, 23 twin pairs were recruited; 11 monozygotic and 2 dizygotic pairs had nonAMD retinal changes or no retinal abnormalities, 9 monozygotic pairs with AMD were all concordant, and 1 dizygotic pair was discordant for basal laminar drusen. The concordance rate of AMD did not differ significantly between monozygotic and dizygotic twin pairs (P = .10) for 1986 through 1991. In 1992 and 1993, 88 twin pairs and one triplet set were recruited; 49 monozygotic and 19 dizygotic pairs had nonAMD retinal changes or no retinal abnormalities, 14 monozygotic pairs with AMD were all concordant, and 2 of 7 dizygotic pairs were concordant for AMD. The nonidentical triplets (1 with and 2 without AMD) were categorized as one of the discordant dizygotic pairs in the statistical evaluation. In nontwin age-matched (within 2 or 5 years of age) or age- and sex-matched sibling pairs the concordance rate of AMD ranged from 16% to 25%. The concordance rate of AMD was significantly higher in monozygotic than in dizygotic twins (P = .001) for 1992 and 1993. The concordance rate was higher for monozygotic twin pairs recruited in 1992 and 1993 than in any of the four subsets of nontwin age-method or age- and sex-matched sibling pairs (P < .0001). Overall, from 1986 through 1993, 23 of 23 monozygotic and 2 of 8 dizygotic twin pairs were concordant for AMD

  7. Dynamic techniques for studies of secular variations in position from ranging to satellites. [using laser range measurements

    NASA Technical Reports Server (NTRS)

    Smith, D. E.; Kolenkiewicz, R.; Agreen, R. W.; Dunn, P. J.

    1974-01-01

    Satellite laser range measurements were applied to the study of latitude variation arising from polar motion, and the solid-earth and ocean tidal distortion of the earth's gravity field. Experiments involving two laser tracking stations were conducted. The relative location of one station with respect to the other was determined by performing simultaneous range measurements to a satellite from two stations several hundred kilometers apart. The application of this technique to the San Andreas Fault Experiment in California is discussed. Future capabilities of spacecraft equipped with laser retroreflectors include: (1) determination of the product of the earth's mass and gravitational constant; (2) measurement of crustal and tectonic motions; (3) determination of the elastic response of the solid-earth tidal forces; (4) measurement of the amplitudes and phase of certain components of the ocean tides; and (5) self-monitoring of the latitude and height variations of the tracking station.

  8. Applicant Age as a Subjective Employability Factor: A Study of Workers over and under Age Fifty.

    ERIC Educational Resources Information Center

    Forte, Catherine Sabin; Hansvick, Christine L.

    1999-01-01

    Three hundred employers in a suburban area of the Pacific Northwest were surveyed for their perceptions of older (ages 50 and over) and younger (aged 49 and under) workers on 12 attributes. In contrast to previous research, this study found more favorable ratings for older workers overall, including categories such as attendance and salary…

  9. Canadian study of health and aging: study methods and prevalence of dementia.

    PubMed Central

    1994-01-01

    OBJECTIVE: To estimate the prevalence of dementia and its subtypes by sex and age group for five regions of Canada. DESIGN: Prevalence survey. SETTING: Community and institutional settings in Canada, excluding those in the two territories, Indian reserves and military units. PARTICIPANTS: Representative sample of people aged 65 and over interviewed between February 1991 and May 1992. Those in the community (9008 subjects) were chosen randomly from medicare lists in nine provinces or from the Enumeration Composite Record in Ontario. People in institutions (1255) were randomly selected from residents in stratified random samples of institutions in each region. INTERVENTIONS: Screening with the Modified Mini-Mental State (3MS) Examination to identify cognitive impairment. Clinical examination of all those in institutions, those in the community with a 3MS score of less than 78 and a sample of those in the community with a 3MS score of 78 or more to diagnose dementia. Dementia and Alzheimer's disease were defined according to established criteria. MAIN OUTCOME MEASURES: Prevalence of dementia of all types, by region, sex and age group, the estimated number of cases in the population by type of dementia and the age-standardized rate per 1000 population. RESULTS: The prevalence estimates suggested that 252,600 (8.0%) of all Canadians aged 65 and over met the criteria for dementia (95% confidence interval [CI] 236,800 to 268,400). These were divided roughly equally between the community and institutional samples; the female:male ratio was 2:1. The age-standardized rate ranged from 2.4%, among those aged 65 to 74 years, to 34.5%, among those aged 85 and over. The corresponding figures for Alzheimer's disease were 5.1% overall (161,000 cases; 95% CI 148,100 to 173,900), ranging from 1.0% to 26.0%; for vascular dementia it was 1.5% overall, ranging from 0.6% to 4.8%. If the prevalence estimates remain constant, the number of Canadians with dementia will rise to 592,000 by

  10. Passive Rotation Range of Motion and Shoulder Subluxation: A Comparative Study

    PubMed Central

    Stanish, William; Kozey, Cheryl

    2009-01-01

    Background Conflicting reports of range of motion (ROM) findings exist related to shoulder instability. Knowledge of range of motion findings among individuals with shoulder subluxation may aid in diagnosis and facilitate appropriate management. Purpose The purpose of this study was to compare passive rotation ROM and determine if a symptom-provoking activity alters ROM between patients with shoulder subluxations and healthy controls. Methods Seventeen symptomatic patients with shoulder subluxations and 14 healthy controls between the ages of 18 and 35 years were recruited. Lateral and medial rotation ROM measures were taken using a universal goniometer. Symptoms were assessed using a 10cm visual analog scale (VAS). Each group performed a symptom-provoking activity, and VAS and ROM measures were repeated. Results A two-factor analysis of variance with repeated measures on pre/post activity demonstrated lower medial rotation measures for the instability group, but no differences for lateral rotation or total range (p < 0.05). A “warm-up” effect was noted, with greater ROM found in each group post activity, with a greater increase noted among controls. Analysis of the ratio of lateral rotation to medial rotation ROM found a significantly greater ratio in the instability group. VAS pain scores were greater in the instability group. Conclusion Shoulder subluxation is not necessarily associated with increased rotation ROM, therefore total ROM findings should not be used to screen for instability. Imbalances in rotation ROM may be associated with symptomatic shoulder instability and may have implications for treatment. PMID:21509102

  11. The Stroop Color-Word Test: Influence of Age, Sex, and Education; and Normative Data for a Large Sample Across the Adult Age Range

    ERIC Educational Resources Information Center

    Van der Elst, Wim; Van Boxtel, Martin P. J.; Van Breukelen, Gerard J. P.; Jolles, Jelle

    2006-01-01

    The Stroop Color-Word Test was administered to 1,856 cognitively screened, healthy Dutch-speaking participants aged 24 to 81 years. The effects of age, gender, and education on Stroop test performance were investigated to adequately stratify the normative data. The results showed that especially the speed-dependent Stroop scores (time to complete…

  12. A new study of shower age distribution in near vertical showers by EAS air shower array

    NASA Technical Reports Server (NTRS)

    Chaudhuri, N.; Basak, D. K.; Goswami, G. C.; Ghosh, B.

    1984-01-01

    The air shower array has been developed since it started operation in 1931. The array covering an area of 900 sq m now incorporates 21 particle density sampling detectors around two muon magnetic spectrographs. The air showers are detected in the size range 10 to the 4th power to 10 to the 6th power particles. A total of 11000 showers has so far been detected. Average values of shower age have been obtained in various shower size ranges to study the dependence of shower age on shower size. The core distance dependence of shower age parameter has also been analyzed for presentation.

  13. A Study in Bivalve Aging and Growth.

    ERIC Educational Resources Information Center

    Schlenker, Karl R.; Schlenker, Richard M.

    1998-01-01

    Describes how high school biology students use the clam to study the bivalve body plan anatomy. Employs an open-ended investigation format that is rich with measurement opportunities including body mass, valve mass, and volume. (DDR)

  14. Reference ranges and determinants of total hCG levels during pregnancy: the Generation R Study.

    PubMed

    Korevaar, Tim I M; Steegers, Eric A P; de Rijke, Yolanda B; Schalekamp-Timmermans, Sarah; Visser, W Edward; Hofman, Albert; Jaddoe, Vincent W V; Tiemeier, Henning; Visser, Theo J; Medici, Marco; Peeters, Robin P

    2015-09-01

    Human chorionic gonadotropin (hCG) is a pregnancy hormone secreted by the placental synctiotrophoblast cell layer that has been linked to fetal growth and various placental, uterine and fetal functions. In order to investigate the effects of hCG on clinical endpoints, knowledge on reference range (RR) methodology and determinants of gestational hCG levels is crucial. Moreover, a better understanding of gestational hCG physiology can improve current screening programs and future clinical management. Serum total hCG levels were determined in 8195 women participating in the Generation R Study. Gestational age specific RRs using 'ultrasound derived gestational age' (US RRs) were calculated and compared with 'last menstrual period derived gestational age' (LMP RRs) and a model-based RR. We also investigated which pregnancy characteristics were associated with hCG levels. Compared to the US RRs, the LMP RRs were lower, most notably for the median and lower limit levels. No considerable differences were found between RRs calculated in the general population or in uncomplicated pregnancies only. Maternal smoking, BMI, parity, ethnicity, fetal gender, placental weight and hyperemesis gravidarum symptoms were associated with total hCG. We provide gestational RRs for total hCG and show that total hCG values and RR cut-offs during pregnancy vary depending on pregnancy dating methodology. This is likely due to the influence of hCG on embryonic growth, suggesting that ultrasound based pregnancy dating might be less reliable in women with high/low hCG levels. Furthermore, we identify different pregnancy characteristics that influence total hCG levels considerably and should therefore be accounted for in clinical studies.

  15. Diet quality and six-year risk of overweight and obesity among mid-age Australian women who were initially in the healthy weight range.

    PubMed

    Aljadani, Haya M; Patterson, Amanda J; Sibbritt, David; Collins, Clare E

    2016-04-01

    Issue addressed The present study investigated the association between diet quality, measured using the Australian Recommended Food Score (ARFS), and 6-year risk of becoming overweight or obese in mid-age women from the Australian Longitudinal Study of Women's Health (ALSWH). Methods Women (n=1107) aged 47.6-55.8 years who were a healthy weight (body mass index (BMI) between ≤18.5 and <25.0kgm(-2)) at baseline and who reported valid total energy intakes were included in the study. BMI was calculated from self-reported data in 2001 and 2007. ARFS scores were calculated from data collected using the Dietary Questionnaire for Epidemiological Studies Version 2. Logistic regression was used to examine the relationship between ARFS score as a continuous variable and risk of becoming overweight or obese. Results The 6-year incidence of overweight and obesity was 18.5% and 1.1%, respectively. The mean (± s.d.) ARFS (maximum possible 74) among those who remained within the healthy weight range and those who became overweight or obese at follow-up was 35.3±8.1 and 34.3±8.8, respectively. There was no relationship between baseline ARFS and risk of becoming overweight or obese over 6 years. Women who were smokers were more likely to become overweight or obese (odds ratio 1.5; 95% confidence interval 1.11-2.09; P=0.008). Conclusions Poor diet quality was common among mid-age women of a healthy weight in the ALSWH. Higher diet quality was not associated with the risk of overweight or obesity after 6 years, yet smoking status was. So what? Better diet quality alone will not achieve maintenance of a healthy weight, but should be encouraged to improve other health outcomes.

  16. Investigation of dielectric behavior of water and thermally aged of XLPE/BaTiO3 composites in the low-frequency range

    NASA Astrophysics Data System (ADS)

    Madani, Lakhdar; Belkhiat, Saad; Berrag, Amine; Nemdili, Saad

    2015-10-01

    Cross-Linked Polyethylene (XLPE) is widely used as insulation in electrical engineering, especially as cable insulation sheaths. In order to improve the dielectric properties susceptible to be modified under the effects of thermal aging and water in an absorption environment, polymers are mixed with ceramics. In this paper, the influence of barium titanate (BaTiO3), on the dielectric properties of XLPE has been studied. Dielectric parameters have been measured using an impedance analyzer RLC (WAYNE KERR 6420 type). Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy and X-ray diffraction were used as characterization techniques. The study has been carried out on two samples of XLPE. A pure sample of each were studied as a unloaded samples to be compared with samples of 5%wt, 10%wt, 15%wt and 20%wt. BaTiO3 loaded XLPE. Afterwards, the composites were subject to humidity and to thermal aging. The incorporation of BaTiO3 1∘C does not modify the crystallinity and morphology of the XLPE and 2∘C reduces the space charges therefore the dielectric losses. tgδ, ɛr and loss index are measured. Frequency response analysis has been followed in the frequency range (20-300 Hz). Experimental results show well that BaTiO3 as nano-filler improves the dielectric properties of XLPE but in excessive content can drive to the cracking and therefore to absorption of water.

  17. Aerosol transport from Chiang Mai, Thailand to Mt. Lulin, Taiwan - Implication of aerosol aging during long-range transport

    NASA Astrophysics Data System (ADS)

    Chuang, Ming-Tung; Lee, Chung-Te; Chou, Charles C.-K.; Engling, Guenter; Chang, Shih-Yu; Chang, Shuenn-Chin; Sheu, Guey-Rong; Lin, Neng-Huei; Sopajaree, Khajornsak; Chang, You-Jia; Hong, Guo-Jun

    2016-07-01

    The transport of biomass burning (BB) aerosol from Indochina may cause a potential effect on climate change in Southeast Asia, East Asia, and the Western Pacific. Up to now, the understanding of BB aerosol composition modification during long-range transport (LRT) is still very limited due to the lack of observational data. In this study, atmospheric aerosols were collected at the Suthep/Doi Ang Khang (DAK) mountain sites in Chiang Mai, Thailand and the Lulin Atmospheric Background Station (Mt. Lulin) in central Taiwan from March to April 2010 and from February to April 2013, respectively. During the study period, an upwind and downwind relationship between the Suthep/DAK and Lulin sites (2400 km apart) was validated by backward trajectories. Comprehensive aerosol properties were resolved for PM2.5 water-soluble inorganic ions, carbonaceous content, water-soluble/insoluble organic carbon (WSOC/WIOC), dicarboxylic acids and their salts (DCAS), and anhydrosugars. A Modification Factor (MF) is proposed by employing non-sea-salt potassium ion (nss-K+) or fractionalized elemental carbon evolved at 580 °C after pyrolized OC correction (EC1-OP) as a BB aerosol tracer to evaluate the mass fraction changes of aerosol components from source to receptor regions during LRT. The MF values of nss-SO42-, NH4+, NO3-, OC1 (fractionalized organic carbon evolved from room temperature to 140 °C), OP (pyrolized OC fraction), DCAS, and WSOC were above unity, which indicated that these aerosol components were enhanced during LRT as compared with those in the near-source region. In contrast, the MF values of anhydrosugars ranged from 0.1 to 0.3, indicating anhydrosugars have degraded during LRT.

  18. Physicochemical characterization of aged biomass burning aerosol after long-range transport to Greece from large scale wildfires in Russia and surrounding regions, Summer 2010

    NASA Astrophysics Data System (ADS)

    Diapouli, E.; Popovicheva, O.; Kistler, M.; Vratolis, S.; Persiantseva, N.; Timofeev, M.; Kasper-Giebl, A.; Eleftheriadis, K.

    2014-10-01

    Smoke aerosol emitted by large scale wildfires in the European part of Russia and Ukraine, was transported to Athens, Greece during August 2010 and detected at an urban background site. Measurements were conducted for physico-chemical characterization of the aged aerosol and included on-line monitoring of PM10 and carbonaceous particles mass concentrations, as well as number size distributions and aerosol optical properties. In addition TSP filter samples were analyzed for major inorganic ions, while morphology and composition of particles was studied by individual particle analysis. Results supported the long-range transport of smoke plumes from Ukraine and Russia burning areas indicated by back trajectory analysis. An increase of 50% and 40% on average in organic (OC) and elemental carbon (EC) concentrations respectively, and more than 95% in carbonate carbon (CC) levels was observed for the biomass burning (BB) transport period of August with respect to the previous month of July. Mean 24-h OC/EC ratio was found in the range 3.2-8.5. Single scattering albedo (SSA) was also increased, indicating abundance of light scattering constituents and/or shift of size distributions towards larger particles. Increase in particle size was further supported by a decreasing trend in absorption Angström exponent (AAE). Ion analysis showed major contribution of secondary species (ammonium sulfate and nitrate) and soil components (Ca2+, Mg2+). Non-sea salt K+ exhibited very good correlation with secondary species, indicating the long-range transport of BB smoke as a possible common source. Individual particle analysis of the samples collected during BB-transport event in Athens revealed elevated number of soot externally mixed with fly ash Ca-rich particles. This result is in agreement with the increased OC and CC levels measured, thus pointing towards the main components comprising the aged BB aerosol microstructure.

  19. Age differences in the motor control of speech: An fMRI study of healthy aging.

    PubMed

    Tremblay, Pascale; Sato, Marc; Deschamps, Isabelle

    2017-03-06

    Healthy aging is associated with a decline in cognitive, executive, and motor processes that are concomitant with changes in brain activation patterns, particularly at high complexity levels. While speech production relies on all these processes, and is known to decline with age, the mechanisms that underlie these changes remain poorly understood, despite the importance of communication on everyday life. In this cross-sectional group study, we investigated age differences in the neuromotor control of speech production by combining behavioral and functional magnetic resonance imaging (fMRI) data. Twenty-seven healthy adults underwent fMRI while performing a speech production task consisting in the articulation of nonwords of different sequential and motor complexity. Results demonstrate strong age differences in movement time (MT), with longer and more variable MT in older adults. The fMRI results revealed extensive age differences in the relationship between BOLD signal and MT, within and outside the sensorimotor system. Moreover, age differences were also found in relation to sequential complexity within the motor and attentional systems, reflecting both compensatory and de-differentiation mechanisms. At very high complexity level (high motor complexity and high sequence complexity), age differences were found in both MT data and BOLD response, which increased in several sensorimotor and executive control areas. Together, these results suggest that aging of motor and executive control mechanisms may contribute to age differences in speech production. These findings highlight the importance of studying functionally relevant behavior such as speech to understand the mechanisms of human brain aging. Hum Brain Mapp, 2017. © 2017 Wiley Periodicals, Inc.

  20. Relocation at older age: results from the Cognitive Function and Ageing Study

    PubMed Central

    Wu, Yu-Tzu; Prina, A. Matthew; Barnes, Linda E.; Matthews, Fiona E.; Brayne, Carol

    2015-01-01

    Background Community environment might play an important role in supporting ageing in place. This paper aims to explore relocation at older age and its associations with individual and community level factors. Methods The postcodes of the 2424 people in the year-10 interview of the Cognitive Function and Ageing Study (CFAS) in England were mapped onto Enumeration Districts and linked to their corresponding Townsend deprivation score and the 2011 rural/urban categories. Multilevel logistic regression was conducted to examine the influence of the baseline individual (age, gender, education and social class) and community (rural/urban categories and area deprivation) level factors on relocation over 10 years. Results One-third of people moved residence after the age of 65 years and over. Older age, low education, low social class and living in rural areas at baseline were associated with higher probability of moving later in life. The likelihood of relocation in later life increased from least to most deprived areas (odds ratio: 2.0, 95% confidence interval: 1.4, 2.8). Conclusions Urban/rural contexts and area deprivation are associated with relocation at older age and indicate that community environment may be relevant to ageing in place. PMID:25922369

  1. A Study on Flow Behavior of AA5086 Over a Wide Range of Temperatures

    NASA Astrophysics Data System (ADS)

    Asgharzadeh, A.; Jamshidi Aval, H.; Serajzadeh, S.

    2016-03-01

    Flow stress behavior of AA5086 was determined using tensile testing at different temperatures from room temperature to 500 °C and strain rates varying between 0.002 and 1 s-1. The strain rate sensitivity parameter and occurrence of dynamic strain aging were then investigated in which an Arrhenius-type model was employed to study the serrated flow. Additionally, hot deformation behavior at temperatures higher than 320 °C was evaluated utilizing hyperbolic-sine constitutive equation. Finally, a feed forward artificial neural network model with back propagation learning algorithm was proposed to predict flow stress for all deformation conditions. The results demonstrated that the strain rate sensitivity at temperature range of 25-270 °C was negative due to occurrence of dynamic strain aging leading to significant reduction in fracture strain. The serrated yielding activation energy was found to be 46.1 kJ/mol. It indicated that the migration of Mg-atoms could be the main reason for this phenomenon. The hot deformation activation energy of AA5086 was also calculated about 202.3 kJ/mol while the dynamic recovery was the main softening process. Moreover, the ANN model having two hidden layers was shown to be an efficient structure for determining flow stress of the examined alloy for all temperatures and strain rates.

  2. Aging Studies of Filled and Unfilled VCE

    SciTech Connect

    Letant, S; Herberg, J; Alviso, C; Small, W; Mulcahy, H; Pearson, M; Wilson, T; Chinn, S; Maxwell, R

    2009-11-10

    This report presents data on the effects of temperature and gamma radiation on the chemical and structural properties of both filled and unfilled VCE material produced by the Kansas City Plant using WR-qualified processes. Thermal effects up to 300 C and gamma irradiation doses of 1 MRad and 25 MRad were investigated under atmospheric conditions. Characterization techniques used in the study comprise Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), Tensile Testing, Solid Phase MicroExtraction - Gas Chromatography/Mass Spectrometry (SPME-GC/MS), phenol extraction followed by HPLC, and various Nuclear Magnetic Resonance (NMR) techniques including: {sup 13}C, {sup 13}C {l_brace}{sup 1}H{r_brace} cross polarization (CP), {sup 1}H magic angle spinning (MAS), 13C{l_brace}{sup 1}H{r_brace} Wide-line-Separation (2D-WISE) and development of Center band-Only Detection of Exchange (CODEX).

  3. Organic Tanks Safety Program: Waste aging studies

    SciTech Connect

    Camaioni, D.M.; Samuels, W.D.; Lenihan, B.D.; Clauss, S.A.; Wahl, K.L.; Campbell, J.A.

    1994-11-01

    The underground storage tanks at the Hanford Complex contain wastes generated from many years of plutonium production and recovery processes, and mixed wastes from radiological degradation processes. The chemical changes of the organic materials used in the extraction processes have a direct on several specific safety issues, including potential energy releases from these tanks. This report details the first year`s findings of a study charged with determining how thermal and radiological processes may change the composition of organic compounds disposed to the tank. Their approach relies on literature precedent, experiments with simulated waste, and studies of model reactions. During the past year, efforts have focused on the global reaction kinetics of a simulated waste exposed to {gamma} radiation, the reactions of organic radicals with nitrite ion, and the decomposition reactions of nitro compounds. In experiments with an organic tank non-radioactive simulant, the authors found that gas production is predominantly radiolytically induced. Concurrent with gas generation they observe the disappearance of EDTA, TBP, DBP and hexone. In the absence of radiolysis, the TBP readily saponifies in the basic medium, but decomposition of the other compounds required radiolysis. Key organic intermediates in the model are C-N bonded compounds such as oximes. As discussed in the report, oximes and nitro compounds decompose in strong base to yield aldehydes, ketones and carboxylic acids (from nitriles). Certain aldehydes can react in the absence of radiolysis to form H{sub 2}. Thus, if the pathways are correct, then organic compounds reacting via these pathways are oxidizing to lower energy content. 75 refs.

  4. Clever mothers balance time and effort in parental care: a study on free-ranging dogs.

    PubMed

    Paul, Manabi; Sau, Shubhra; Nandi, Anjan K; Bhadra, Anindita

    2017-01-01

    Mammalian offspring require parental care, at least in the form of nursing during their early development. While mothers need to invest considerable time and energy in ensuring the survival of their current offspring, they also need to optimize their investment in one batch of offspring in order to ensure future reproduction and hence lifetime reproductive success. Free-ranging dogs live in small social groups, mate promiscuously and lack the cooperative breeding biology of other group-living canids. They face high early-life mortality, which in turn reduces fitness benefits of the mother from a batch of pups. We carried out a field-based study on free-ranging dogs in India to understand the nature of maternal care. Our analysis reveals that mothers reduce investment in energy-intensive active care and increase passive care as the pups grow older, thereby keeping overall levels of care more or less constant over pup age. Using the patterns of mother-pup interactions, we define the different phases of maternal care behaviour.

  5. Clever mothers balance time and effort in parental care: a study on free-ranging dogs

    PubMed Central

    Sau, Shubhra

    2017-01-01

    Mammalian offspring require parental care, at least in the form of nursing during their early development. While mothers need to invest considerable time and energy in ensuring the survival of their current offspring, they also need to optimize their investment in one batch of offspring in order to ensure future reproduction and hence lifetime reproductive success. Free-ranging dogs live in small social groups, mate promiscuously and lack the cooperative breeding biology of other group-living canids. They face high early-life mortality, which in turn reduces fitness benefits of the mother from a batch of pups. We carried out a field-based study on free-ranging dogs in India to understand the nature of maternal care. Our analysis reveals that mothers reduce investment in energy-intensive active care and increase passive care as the pups grow older, thereby keeping overall levels of care more or less constant over pup age. Using the patterns of mother–pup interactions, we define the different phases of maternal care behaviour. PMID:28280555

  6. Hearing Loss as a Function of Aging and Diabetes Mellitus: A Cross Sectional Study

    PubMed Central

    Park, Dong Choon; Kim, MyungGu; Chung, Ji Hyun; Kim, Sang Hoon; Yeo, Seung Geun

    2014-01-01

    Background Although hearing loss may be caused by various factors, it is also a natural phenomenon associated with the aging process. This study was designed to assess the contributions of diabetes mellitus (DM) and hypertension, both chronic diseases associated with aging, as well as aging itself, to hearing loss in health screening examinees. Methods This study included 37,773 individuals who underwent health screening examinations from 2009 to 2012. The relationships between hearing threshold and subject age, hearing threshold at each frequency based on age group, the degree of hearing loss and the presence or absence of hypertension and DM were evaluated. Results The prevalence of hearing loss increased with age, being 1.6%, 1.8%, 4.6%, 14.0%, 30.8%, and 49.2% in subjects in their twenties, thirties, forties, fifties, sixties, and seventies, respectively (p<0.05). Hearing value per frequency showed aging-based changes, in the order of 6000, 4000, 2000, 1000 and 500 Hz, indicating greater hearing losses at high frequencies. The degree of hearing loss ranged from mild to severe. Aging and DM were correlated with the prevalence of hearing loss (p<0.05). There was no statistically significant association between hearing loss and hypertension after adjusting for age and DM. Conclusions The prevalence of hearing loss increases with age and the presence of DM. Hearing loss was greatest at high frequencies. In all age groups, mild hearing loss was the most common form of hearing loss. PMID:25549095

  7. Drosophila geotaxis as a tool for the study of aging

    NASA Technical Reports Server (NTRS)

    Schnebel, Edgar M.; Hoffmann, R. Nicholas; Grossfield, Joe

    1988-01-01

    Age dependent changes in geotaxis profiles were examined in 27 wild-type populations of Drosophila, representing a diversity of species, semispecies and strains. In addition, four strains of D. melanogaster were tested. Tests were carried out at a minimum of three test ages, and involve the use of a calibrated, adjustable inclined plane that can be set at any angle between 0 and 85 deg. Among selected lines, decline in geotactic response occurs later in the long lived flies than in the controls. Longer lived flies continue to show an increase in negative geotactic response through age 14 days. These results suggest that common processes may be influencing the rate of decline in geotactic response and longevity. Further analysis of the mechanisms underlying age dependent changes in geotaxis may reveal factors which influence the aging process itself. The use of geotaxis aging markers in a broad range of Drosophila species reflecting varying degrees of genetic relatedness is proposed to test the universality vs. specificity of aging processes.

  8. "Oxygen supply" as modulator of aging processes: hypoxia and hyperoxia models for aging studies.

    PubMed

    Cataldi, Amelia; Di Giulio, Camillo

    2009-07-01

    Cell growth is regulated by several factors, including oxygen supply, which influence cell metabolism. Aging is characterized by decreased oxygen supply to tissue, a reduction of tissue PO(2) and of the activity of several enzymes and metabolic factors. The oxygen-gradient diffusion at capillary tissue level is essential for the cellular survival, while the homeostasis of the oxygen in the arterial blood is mediated by reflexes sensitive to oxygen decrease and by release of several factors. Aging is correlated with a reduction of cells' oxygen supply concomitant to a parallel decrease in oxygen demand by tissues. Both chronic hypoxia or hyperoxia are considered as stresses. Indeed, in both conditions, free radical species, which damage structural and functional components of the membrane, are generated. ROS (reactive oxygen species) are physiological products of aerobic life and their accumulation affects aging. Because hypoxia per se modulates mitochondria activity, influencing oxygen consumption, hypoxia and aging could share some link. Moreover, the observation that in hypoxia or hyperoxia there is an accumulation of lipofucsine as a general reaction to stress is consistent with the accumulation of such components during aging. Correlation between hypoxia-hyperoxia and life-span remains open until we solve the question of how and why do cells sense oxygen. In other words, to better understand aging we need to know what O(2) species are being sensed by cells. In conclusion, hypoxia and hyperoxia represent an experimental model adequate for studying aging processes.

  9. Undergraduate Knowledge of Aging: A Comparative Study of Biopsychosocial Content

    ERIC Educational Resources Information Center

    Damron-Rodriguez, JoAnn; Funderburk, Brooke; Lee, Martin; Solomon, David H.

    2004-01-01

    This study assesses undergraduate knowledge of aging, distinguishing between types of deficits (ignorance vs. misinformation) and content areas as delineated by a biopsychosocial framework. Knowledge is examined as an outcome of taking an aging elective, while accounting for course rating and knowledge retention. A diverse body of UCLA…

  10. What Drives Teacher Engagement: A Study of Different Age Cohorts

    ERIC Educational Resources Information Center

    Guglielmi, Dina; Bruni, Ilaria; Simbula, Silvia; Fraccaroli, Franco; Depolo, Marco

    2016-01-01

    Despite the growing body of research on work engagement, little is known about what drives work engagement among different age cohorts. This study aims to investigate whether engagement varies across age cohorts and examines the job resources that foster teacher engagement. A questionnaire was distributed to 537 teachers who were employed in…

  11. Age and Workers' Perceptions of Workplace Safety: A Comparative Study

    ERIC Educational Resources Information Center

    Gyekye, Seth Ayim; Salminen, Simo

    2009-01-01

    The study examined the relationship between age and I) safety perception; ii) job satisfaction; iii) compliance with safety management policies; and (iv) accident frequency. Participants were Ghanaian industrial workers (N = 320) categorized into 4 age groups: 19-29 years; 30-39 years; 40-50 years; and 51 years and above. Workplace safety…

  12. Aging and Alzheimer's Disease: Lessons from the Nun Study.

    ERIC Educational Resources Information Center

    Snowdon, David A.

    1997-01-01

    Describes a woman who maintained high cognitive test scores until her death at 101 years of age despite anatomical evidence of Alzheimer's disease. The woman was part of a larger "Nun Study" in which 678 sisters donated their brains to teach others about the etiology of aging and Alzheimer's disease. Findings are discussed. (RJM)

  13. Social Factors and Healthy Aging: Findings from the Louisiana Healthy Aging Study (LHAS)

    PubMed Central

    Cherry, Katie E.; Brown, Jennifer Silva; Kim, Sangkyu; Jazwinski, S. Michal

    2016-01-01

    Social behaviors are associated with health outcomes in later life. The authors examined relationships among social and physical activities and health in a lifespan sample of adults (N = 771) drawn from the Louisiana Healthy Aging Study (LHAS). Four age groups were compared: younger (21-44 years), middle-aged (45-64 years), older (65-84 years), and oldest-old adults (85 to 101 years). Linear regression analyses indicated that physical activity, hours spent outside of the house, and social support were significantly associated with self-reported health, after controlling for sociodemographic factors. Number of clubs was significantly associated with objective health status, after controlling for sociodemographic factors. These data indicate that social and physical activities remain an important determinant of self-perceived health into very late adulthood. Implications of these data for current views on successful aging are discussed. PMID:27034910

  14. Social Factors and Healthy Aging: Findings from the Louisiana Healthy Aging Study (LHAS).

    PubMed

    Cherry, Katie E; Brown, Jennifer Silva; Kim, Sangkyu; Jazwinski, S Michal

    2016-02-01

    Social behaviors are associated with health outcomes in later life. The authors examined relationships among social and physical activities and health in a lifespan sample of adults (N = 771) drawn from the Louisiana Healthy Aging Study (LHAS). Four age groups were compared: younger (21-44 years), middle-aged (45-64 years), older (65-84 years), and oldest-old adults (85 to 101 years). Linear regression analyses indicated that physical activity, hours spent outside of the house, and social support were significantly associated with self-reported health, after controlling for sociodemographic factors. Number of clubs was significantly associated with objective health status, after controlling for sociodemographic factors. These data indicate that social and physical activities remain an important determinant of self-perceived health into very late adulthood. Implications of these data for current views on successful aging are discussed.

  15. Reference Ranges for Uterine Artery Pulsatility Index during the Menstrual Cycle: A Cross-Sectional Study

    PubMed Central

    Guedes-Martins, Luís; Gaio, Rita; Saraiva, Joaquim; Cerdeira, Sofia; Matos, Liliana; Silva, Elisabete; Macedo, Filipe; Almeida, Henrique

    2015-01-01

    Background Cyclic endometrial neoangiogenesis contributes to changes in local vascular patterns and is amenable to non-invasive assessment with Doppler sonography. We hypothesize that the uterine artery (UtA) impedance, measured by its pulsatility index (PI), exhibits a regular pattern during the normal menstrual cycle. Therefore, the main study objective was to derive normative new day-cycle-based reference ranges for the UtA-PI during the entire cycle from days 1 to 34 according to the isolated time effect and potential confounders such as age and parity. Methods From January 2009 to December 2012, a cross-sectional study of 1,821 healthy women undergoing routine gynaecological ultrasound was performed. The Doppler flow of the right and left UtA-PI was studied transvaginally by colour and pulsed Doppler imaging. The mean right and left values and the presence or absence of a bilateral protodiastolic notch were recorded. Reference intervals for the PI according to the cycle day were generated by classical linear regression. Results The majority of patients (97.5%) presented unilateral or bilateral UtA notches. The crude 5th, 50th, and 95th reference percentile curves of the UtA-PI at 1–34 days of the normal menstrual cycle were derived. In all curves, a progressive significant decrease occurred during the first 13 days, followed by an increase and recovery in the UtA-PI. The adjusted 5th, 50th, and 95th reference percentile curves for the effects of age and parity were also obtained. These two conditions generated an approximately identical UtA-PI pattern during the cycle, except with small but significant reductions at the temporal extremes. Conclusions The median, 5th, and the 95th percentiles of the UtA-PI decrease during the first third of the menstrual cycle and recover to their initial values during the last two thirds of the cycle. The rates of decrease and recovery depend significantly on age and parity. PMID:25742286

  16. An expanded age range for meningococcal meningitis: molecular diagnostic evidence from population-based surveillance in Asia

    PubMed Central

    2012-01-01

    Background To understand epidemiologic patterns of meningococcal disease in Asia, we performed a retrospective molecular analysis of cerebrospinal fluid (CSF) specimens collected in prospective surveillance among children aged < 5 years of age in China, South Korea, and Vietnam. Methods A total of 295 isolates and 2,302 CSFs were tested by a meningococcal species- and serogroup-specific polymerase chain reaction (PCR) assay targeting the Neisseria meningitidis (Nm) ctrA gene. Multi-locus sequence typing (MLST) was performed in Nm gene amplification analysis and incidence rates for meningococcal meningitis were estimated. Results Among 295 isolates tested, 10 specimens from Vietnam were confirmed as serogroup B and all were Sequence Type (ST) 1576 by MLST. Among the 2,032 CSF specimen tested, 284 (14%) were confirmed by PCR (ctrA gene), including 67 (23.6%) from China, 92 (32.4%) from Korea, and 125 (44.0%) from Vietnam. Neonates and infants aged < 6 months of age accounted for more than 50% of Nm-PCR positive CSF. Two CSF specimens from Vietnam were identified as serogroup B using MLST. In addition, 44 specimens underwent sequencing to confirm meningococcal serogroup; of these, 21 (48%) were serogroup C, 12 (27%) were serogroup X, 9 (20%) were serogroup Y and 2 (5%) were serogroup B. The incidence rates of meningococcal meningitis among children < 5 years of age was highest in Vietnam (7.4/100,000 [95% CI, 3.6—15.3] followed by Korea (6.8/100,000 [95% CI, 3.5-13.5] and China (2.1/100,000) [95% CI, 0.7-6.2]). Conclusions These results suggest that there is a previously undetected, yet substantial burden of meningococcal meningitis among infants and young children. Standardized, sensitive and specific molecular diagnostic assays with Nm serogrouping capacity are needed throughout Asia to understand the true burden of N. meningitidis disease. PMID:23164061

  17. Studies on Training Ground Observers to Estimate Range to Aerial Targets.

    ERIC Educational Resources Information Center

    McCluskey, Michael R.; And Others

    Six pilot studies were conducted to determine the effects of training on range estimation performance for aerial targets, and to identify some of the relevant variables. Observers were trained to estimate ranges of 350, 400, 800, 1,500, or 2,500 meters. Several variations of range estimation training methods were used, including immediate…

  18. The trajectory of the blood DNA methylome ageing rate is largely set before adulthood: evidence from two longitudinal studies.

    PubMed

    Kananen, L; Marttila, S; Nevalainen, T; Kummola, L; Junttila, I; Mononen, N; Kähönen, M; Raitakari, O T; Hervonen, A; Jylhä, M; Lehtimäki, T; Hurme, M; Jylhävä, J

    2016-06-01

    The epigenetic clock, defined as the DNA methylome age (DNAmAge), is a candidate biomarker of ageing. In this study, we aimed to characterize the behaviour of this marker during the human lifespan in more detail using two follow-up cohorts (the Young Finns study, calendar age i.e. cAge range at baseline 15-24 years, 25-year-follow-up, N = 183; The Vitality 90+ study, cAge range at baseline 19-90 years, 4-year-follow-up, N = 48). We also aimed to assess the relationship between DNAmAge estimate and the blood cell distributions, as both of these measures are known to change as a function of age. The subjects' DNAmAges were determined using Horvath's calculator of epigenetic cAge. The estimate of the DNA methylome age acceleration (Δ-cAge-DNAmAge) demonstrated remarkable stability in both cohorts: the individual rank orders of the DNAmAges remained largely unchanged during the follow-ups. The blood cell distributions also demonstrated significant intra-individual correlation between the baseline and follow-up time points. Interestingly, the immunosenescence-associated features (CD8+CD28- and CD4+CD28- cell proportions and the CD4/CD8 cell ratio) were tightly associated with the estimate of the DNA methylome age. In summary, our data demonstrate that the general level of Δ-cAge-DNAmAge is fixed before adulthood and appears to be quite stationary thereafter, even in the oldest-old ages. Moreover, the blood DNAmAge estimate seems to be tightly associated with ageing-associated shifts in blood cell composition, especially with those that are the hallmarks of immunosenescence. Overall, these observations contribute to the understanding of the longitudinal aspects of the DNAmAge estimate.

  19. Perspectives on healthy aging among Thai elderly: a qualitative study.

    PubMed

    Thanakwang, Kattika; Soonthorndhada, Kusol; Mongkolprasoet, Jiraporn

    2012-12-01

    In this qualitative study, we provide an in-depth understanding of the views of healthy aging among Thai elderly and explore the ways that contribute to healthy aging. Data were collected using focus groups and in-depth interviews in four selected provinces of Thailand, and were analyzed using content analysis. The results revealed that Thai elderly described being healthy as the result of multiple components involving physical, mental, and social well-being. Healthy aging was viewed as an absence of serious diseases, having functional independence, a positive psycho-emotional outlook, and making a social contribution. The factors considered to contribute to healthy aging included activities promoting physical and psychological health, as well as active engagement in social activities. Understanding how the elderly define healthy aging and identifying the most important components and factors that contribute to being healthy provides insight into possible policy implications and interventions to promote health and well-being among Thai elderly.

  20. Studies in cutaneous aging: I. The elastic fiber network

    SciTech Connect

    Braverman, I.M.; Fonferko, E.

    1982-05-01

    We studied by light and electron microscopy the elastic fibers in he sun exposed and sun protected skin of normal and psoriatic individuals of different ages in order to separate the changes of actinic damage from those of chronological aging. The sun exposed skin showed 2 types of elastic fiber abnormalities-one related to actinic damage and the other to chronological aging. The sun protected buttock skin showed only the latter. From ages 30 to 70, a minority of the elastic fibers exhibited abnormalities that appeared to represent a process of fiber disintegration. After age 70, the majority of elastic fibers showed these abnormalities. These abnormalities were present without accompanying inflammatory cells. Also, there was morphological evidence of continuing synthesis of elastic fibers during the lifetime of these subjects, except that from ages 50-93, the fibers appeared to be loosely, rather than compactly, assembled. Incubation of dermal slices from buttock skin of young adults with porcine pancreatic elastase and bovine chymotrypsin produced elastic fiber degradation that closely simulated the changes that were observed in aged sun protected skin. Researcher propose that one of the features of cutaneous aging is a slow, spontaneous, progressive degradative process inherent in the elastic fiber that can be enzymatically accelerated from decades to hours by elastase and chymotrypsin.

  1. Ovarian cycle activity varies with respect to age and social status in free-ranging elephants in Addo Elephant National Park, South Africa.

    PubMed

    Freeman, Elizabeth W; Meyer, Jordana M; Putman, Sarah B; Schulte, Bruce A; Brown, Janine L

    2013-01-01

    Free-ranging African elephants live in a fission-fusion society, at the centre of which is the matriarch. Matriarchs are generally older females that guide their families to resources and co-ordinate group defense. While much is known about elephant society, knowledge is generally lacking about how age affects the physiology of wild elephants. Investigation of the ovarian activity of free-ranging elephants could provide insight into the reproductive ageing process, with implications for population management. Faecal samples were collected from 46 individuals ranging in age from 14 to 60 years for a 2-year period, and progestagen metabolite analyses were used to examine relationships between social status, age, season, and ovarian activity in female elephants in Addo Elephant National Park, South Africa. Social status was the strongest predictor of faecal progestagen metabolite concentrations in non-pregnant elephants, with grand matriarchs (n = 6) having the lowest values compared with matriarchs (n = 21) and non-matriarch females (n = 19). Likewise, social status and age were the strongest predictors of faecal progestagen metabolite concentrations in pregnant elephants (n = 27). The number of years since a non-pregnant female gave birth to her last calf (post-partum duration) was longer for older females with a higher social status, as well as during the dry season. Our results indicate that social standing and age of elephants are related to reproductive function, and that older females exhibit reductions in ovarian capacity. These results expand our understanding of reproduction and fertility throughout an elephant's lifespan, and the factors that impact gonadal function in free-ranging females. Given that possible over-abundance of elephants in areas such as Addo Elephant National Park is fuelling the debate over how best to manage these populations, knowledge about the reproductive potential of high-ranking females can provide managers with

  2. Familial influences on the full range of variability in attention and activity levels during adolescence: A longitudinal twin study.

    PubMed

    Peng, Chun-Zi; Grant, Julia D; Heath, Andrew C; Reiersen, Angela M; Mulligan, Richard C; Anokhin, Andrey P

    2016-05-01

    To investigate familial influences on the full range of variability in attention and activity across adolescence, we collected maternal ratings of 339 twin pairs at ages 12, 14, and 16, and estimated the transmitted and new familial influences on attention and activity as measured by the Strengths and Weaknesses of Attention-Deficit/Hyperactivity Disorder Symptoms and Normal Behavior Scale. Familial influences were substantial for both traits across adolescence: genetic influences accounted for 54%-73% (attention) and 31%-73% (activity) of the total variance, and shared environmental influences accounted for 0%-22% of the attention variance and 13%-57% of the activity variance. The longitudinal stability of individual differences in attention and activity was largely accounted for by familial influences transmitted from previous ages. Innovations over adolescence were also partially attributable to familial influences. Studying the full range of variability in attention and activity may facilitate our understanding of attention-deficit/hyperactivity disorder's etiology and intervention.

  3. Childhood predictors of military fitness: a prospective, community-based, follow-up study from age 8 to age 18.

    PubMed

    Multimäki, Petteri; Sourander, Andre; Nikolakaros, Georgios; Helenius, Hans; Aronen, Eeva; Tamminen, Tuula; Kumpulainen, Kirsti; Moilanen, Irma; Piha, Jorma; Almqvist, Fredrik; Parkkola, Kai

    2008-02-01

    Knowledge of the impact of childhood psychosocial problems on success in military service is scarce. The purpose of the study was to assess whether childhood psychosocial problems are associated with suitability for military service. The subjects were 2,622 Finnish boys born in 1981. They were first assessed with the Rutter parent and teacher questionnaires and self-reports (Children's Depression Inventory) at age 8. Their suitability for military service was assessed at age 18. A wide range of childhood problems, especially internalizing disorders, predicted release from military service. All informants had predictive association with later suitability for military service. The majority of children with psychiatric problems were later estimated to be fit for military service. The results show a predictive association between childhood psychiatric problems and early adult psychosocial impairment, as estimated by the ability to serve in the military forces.

  4. A computational approach to studying ageing at the individual level

    PubMed Central

    Mourão, Márcio A.; Schnell, Santiago; Pletcher, Scott D.

    2016-01-01

    The ageing process is actively regulated throughout an organism's life, but studying the rate of ageing in individuals is difficult with conventional methods. Consequently, ageing studies typically make biological inference based on population mortality rates, which often do not accurately reflect the probabilities of death at the individual level. To study the relationship between individual and population mortality rates, we integrated in vivo switch experiments with in silico stochastic simulations to elucidate how carefully designed experiments allow key aspects of individual ageing to be deduced from group mortality measurements. As our case study, we used the recent report demonstrating that pheromones of the opposite sex decrease lifespan in Drosophila melanogaster by reversibly increasing population mortality rates. We showed that the population mortality reversal following pheromone removal was almost surely occurring in individuals, albeit more slowly than suggested by population measures. Furthermore, heterogeneity among individuals due to the inherent stochasticity of behavioural interactions skewed population mortality rates in middle-age away from the individual-level trajectories of which they are comprised. This article exemplifies how computational models function as important predictive tools for designing wet-laboratory experiments to use population mortality rates to understand how genetic and environmental manipulations affect ageing in the individual. PMID:26865300

  5. Progression of aging in Mexico: the Mexican Health and Aging Study (MHAS) 2012

    PubMed Central

    Wong, Rebeca; Michaels-Obregón, Alejandra; Palloni, Alberto; Gutiérrez-Robledo, Luis Miguel; González-González, César; López-Ortega, Mariana; Téllez-Rojo, Martha María; Mendoza-Alvarado, Laura Rosario

    2015-01-01

    Objective To describe the third wave of the Mexican Health and Aging Study (MHAS), completed in 2012, and present preliminary results. Materials and methods Descriptive analyses by gender and age group of demographic and socioeconomic characteristics, health conditions and health behaviors, as well as social support and life satisfaction measures are presented. In addition, external validations are presented by comparing MHAS 2012 indicators with other national data sources. Results For the panel of older adults in the sample, the rate of health care insurance coverage increased greatly between 2001 and 2012, a significantly higher change in rural compared to urban areas. The results for 2012 are consistent with the previous two waves for the main indicators of health and physical disability prevalence, risk factors, and behaviors. Conclusions The MHAS offers a unique opportunity to study aging in Mexico, as well as to complete cross-national comparisons. The cumulative number of deaths in the cohort should support the study of mortality and its association with health outcomes and behaviors over the life cycle. In addition, the sub-samples of objective markers will enable methodological research on self-reports and associations of biomarkers in old age with similar health outcomes and behaviors. PMID:26172238

  6. A Study of Correlation of Various Growth Indicators with Chronological Age

    PubMed Central

    Sandhu, Navreet; Puri, Taruna; Gulati, Ritika; Kashyap, Rita

    2015-01-01

    ABSTRACT Introduction: The aim of this study was to assess the relationship of chronological age with cervical vertebrae skeletal maturation, frontal sinus width and antegonial notch depth and a correlation, if any, among the three variables. Materials and methods: The samples were derived from lateral cephalometric radiographs of 80 subjects (40 males, 40 females; age range: 10 to 19 years). Cervical vertebral development was evaluated by the method of Hassel and Farman, frontal sinus width was measured by the method described by Ertürk and antegonial notch depth as described by Singer et al. The Pearson’s correlation coefficients were estimated to assess the relationship of chronological age with cervical vertebrae skeletal maturation, frontal sinus width and antegonial notch depth. Results: The Pearson’s correlation coefficient were 0.855 (p < 0.001) between chronological age and cervical vertebrae skeletal maturation, and 0.333 (p < 0.001) between chronological age and frontal sinus width. Conclusion: A highly significant positive correlation was found between chronological age and cervical vertebrae skeletal maturation, and between chronological age and frontal sinus width. Nonsignificant correlation was found between chronological age and antegonial notch depth. How to cite this article: Singh S, Sandhu N, Puri T, Gulati R, Kashyap R. A Study of Correlation of Various Growth Indicators with Chronological Age. Int J Clin Pediatr Dent 2015;8(3): 190-195. PMID:26628853

  7. Age-related differences in emotion recognition ability: a cross-sectional study.

    PubMed

    Mill, Aire; Allik, Jüri; Realo, Anu; Valk, Raivo

    2009-10-01

    Experimental studies indicate that recognition of emotions, particularly negative emotions, decreases with age. However, there is no consensus at which age the decrease in emotion recognition begins, how selective this is to negative emotions, and whether this applies to both facial and vocal expression. In the current cross-sectional study, 607 participants ranging in age from 18 to 84 years (mean age = 32.6 +/- 14.9 years) were asked to recognize emotions expressed either facially or vocally. In general, older participants were found to be less accurate at recognizing emotions, with the most distinctive age difference pertaining to a certain group of negative emotions. Both modalities revealed an age-related decline in the recognition of sadness and -- to a lesser degree -- anger, starting at about 30 years of age. Although age-related differences in the recognition of expression of emotion were not mediated by personality traits, 2 of the Big 5 traits, openness and conscientiousness, made an independent contribution to emotion-recognition performance. Implications of age-related differences in facial and vocal emotion expression and early onset of the selective decrease in emotion recognition are discussed in terms of previous findings and relevant theoretical models.

  8. Aging study of boiling water reactor high pressure injection systems

    SciTech Connect

    Conley, D.A.; Edson, J.L.; Fineman, C.F.

    1995-03-01

    The purpose of high pressure injection systems is to maintain an adequate coolant level in reactor pressure vessels, so that the fuel cladding temperature does not exceed 1,200{degrees}C (2,200{degrees}F), and to permit plant shutdown during a variety of design basis loss-of-coolant accidents. This report presents the results of a study on aging performed for high pressure injection systems of boiling water reactor plants in the United States. The purpose of the study was to identify and evaluate the effects of aging and the effectiveness of testing and maintenance in detecting and mitigating aging degradation. Guidelines from the United States Nuclear Regulatory Commission`s Nuclear Plant Aging Research Program were used in performing the aging study. Review and analysis of the failures reported in databases such as Nuclear Power Experience, Licensee Event Reports, and the Nuclear Plant Reliability Data System, along with plant-specific maintenance records databases, are included in this report to provide the information required to identify aging stressors, failure modes, and failure causes. Several probabilistic risk assessments were reviewed to identify risk-significant components in high pressure injection systems. Testing, maintenance, specific safety issues, and codes and standards are also discussed.

  9. Genetic Contribution to Biological Aging: The Framingham Study

    PubMed Central

    Karasik, David; Hannan, Marian T.; Cupples, L. Adrienne; Felson, David T.; Kiel, Douglas P.

    2005-01-01

    This study assessed the contribution of genetic and nongenetic factors to biological aging in American Caucasians. The studied sample included 1402 members of 288 pedigrees from the Framingham Heart Study. The original cohort participants received hand radiography in 1967–1969 (mean age, 58.7 years) and their offspring in 1992–1993 (mean age, 51.6 years). An osseographic score was applied to hand radiographs. Standardized residuals between Osseographic Scoring System-predicted age and actual age were used as a measure of biological age (BA). In variance component genetic analysis, sex, cohort, height, body mass index, and, in women, menopausal status and estrogen use, jointly explained approximately 6% of the total variance of BA. Genetic factors explained an additional 57%. Linkage analysis of covariate-adjusted BA suggested the presence of quantitative trait loci on chromosomes 3p, 7q, 11p, 16q, and 21q. In conclusion, the variation in BA measured by radiography was strongly governed by genetic factors in a sample of American adults. PMID:15031305

  10. Statistical Approaches for the Study of Cognitive and Brain Aging

    PubMed Central

    Chen, Huaihou; Zhao, Bingxin; Cao, Guanqun; Proges, Eric C.; O'Shea, Andrew; Woods, Adam J.; Cohen, Ronald A.

    2016-01-01

    Neuroimaging studies of cognitive and brain aging often yield massive datasets that create many analytic and statistical challenges. In this paper, we discuss and address several limitations in the existing work. (1) Linear models are often used to model the age effects on neuroimaging markers, which may be inadequate in capturing the potential nonlinear age effects. (2) Marginal correlations are often used in brain network analysis, which are not efficient in characterizing a complex brain network. (3) Due to the challenge of high-dimensionality, only a small subset of the regional neuroimaging markers is considered in a prediction model, which could miss important regional markers. To overcome those obstacles, we introduce several advanced statistical methods for analyzing data from cognitive and brain aging studies. Specifically, we introduce semiparametric models for modeling age effects, graphical models for brain network analysis, and penalized regression methods for selecting the most important markers in predicting cognitive outcomes. We illustrate these methods using the healthy aging data from the Active Brain Study. PMID:27486400

  11. Stability and Change in Intelligence from Age 12 to Age 52: Results from the Luxembourg MAGRIP Study

    ERIC Educational Resources Information Center

    Schalke, Daniela; Brunner, Martin; Geiser, Christian; Preckel, Franzis; Keller, Ulrich; Spengler, Marion; Martin, Romain

    2013-01-01

    The present longitudinal study tackled 2 key aspects of the development of intelligence across a 40-year time period from age 12 to age 52 concerning (a) stability and change in the structure of intelligence with reference to the age differentiation-dedifferentiation hypothesis (how different cognitive abilities relate to each other across age)…

  12. Spinal alignment evolution with age: A prospective gait analysis study

    PubMed Central

    Pesenti, Sébastien; Blondel, Benjamin; Peltier, Emilie; Viehweger, Elke; Pomero, Vincent; Authier, Guillaume; Fuentes, Stéphane; Jouve, Jean-Luc

    2017-01-01

    AIM To describe, using gait analysis, the development of spinal motion in the growing child. METHODS Thirty-six healthy children aged from 3 to 16 years old were included in this study for a gait analysis (9 m-walk). Various kinematic parameters were recorded and analyzed such as thoracic angle (TA), lumbar angle (LA) and sagittal vertical axis (SVA). The kinetic parameters were the net reaction moments (N.m/kg) at the thoracolumbar and lumbosacral junctions. RESULTS TA and LA curves were not statistically correlated to the age (respectively, P = 0.32 and P = 0.41). SVA increased significantly with age (P < 0.001). Moments in sagittal plane at the lumbosacral junction were statistically correlated to the age (P = 0.003), underlining the fact that sagittal mechanical constraints at the lumbosacral junction increase with age. Moments in transversal plane at the thoracolumbar and lumbosacral junctions were statistically correlated to the age (P = 0.0002 and P = 0.0006), revealing that transversal mechanical constraints decrease with age. CONCLUSION The kinetic analysis showed that during growth, a decrease of torsional constraint occurs while an increase of sagittal constraint is observed. These changes in spine biomechanics are related to the crucial role of the trunk for bipedalism acquisition, allowing stabilization despite lower limbs immaturity. With the acquisition of mature gait, the spine will mainly undergo constraints in the sagittal plane. PMID:28361018

  13. Childhood immunization and atopic disease into middle-age--a prospective cohort study.

    PubMed

    Matheson, Melanie C; Haydn Walters, E; Burgess, John A; Jenkins, Mark A; Giles, Graham G; Hopper, John L; Abramson, Michael J; Dharmage, Shyamali C

    2010-03-01

    The association between childhood immunizations and risk of atopic diseases is unclear. No study has examined possible associations between childhood immunizations and such diseases in middle age. The Tasmanian Longitudinal Health Study (TAHS) is a population based cohort study of respiratory disease. The TAHS participants were followed from 7 to 44 yrs of age. Immunizations during childhood were examined for any association with asthma and atopic disease at age 44 yrs. Multivariable regression models were used to estimate relative risks while adjusting for confounders. Cox regression was used to estimate the association between childhood immunizations and asthma developing after the age of 7 yrs. We found no association between any childhood immunization (Diphtheria, Tetanus, Pertussis, Polio, Smallpox) and asthma (ORs ranged from 0.87 to 1.17 p > 0.05), eczema (ORs ranged from 0.99 to 1.07 p > 0.05), food allergy (ORs ranged from 0.97 to 1.11 p > 0.05), or hay fever (ORs ranged from 1.02 to 1.05 p > 0.05) at age 44. Nor did we find any association between childhood immunizations and an increased risk of incident asthma after the age of 7 yrs (Diphtheria HR = 1.06, 95% CI 0.82, 1.36; Tetanus HR = 1.13, 95% CI 0.88, 1.44; Pertussis HR = 1.03, 95% CI 0.81, 1.30; Polio HR = 1.15, 95% CI 0.86, 1.54; Smallpox HR = 1.21, 95% CI 0.99, 1.48; DTP HR = 1.05, 95% CI 0.85, 1.30). Our analysis does not support any association between common childhood immunizations and risk of asthma and atopic disease in middle-age. Our findings should provide reassurance that in terms of life time risk of asthma and atopic disease, childhood immunization is safe.

  14. The Mount Evans batholith in the Colorado Front Range: revision of its age and reinterpretation of its structure

    USGS Publications Warehouse

    Aleinikoff, J.N.; Reed, J.C.; Dewitt, E.

    1993-01-01

    The Mount Evans batholith is composed of a main phase of massive to conspicuously foliated monzogranite and granodiorite and undeformed aplite and pegmatite. The Mount Evans batholith was previously considered to be part of the 1.7 Ga Routt Plutonic Suite. New U-Pb zircon ages on four samples (granodiorite, monzogranite, and granite), however, indicate that the batholith was emplaced at 1442 ?? 2 Ma and belongs to the Berthoud Plutonic Suite. Most of the batholith has igneous textures and structures, except in the vicinity of the Idaho Springs-Ralston shear zone where those features are tectonically recrystallized and foliated. The Mount Evans batholith is anomalous in composition and structure compared to most other 1.4 Ga plutons of the southwestern US. The differences probably reflect different sources of partial melting; the specific tectonic setting where rocks of such disparate origin are temporally and spatially juxtaposed is not understood. -from Authors

  15. Molecular studies of exercise, skeletal muscle, and ageing

    PubMed Central

    Timmons, James A.; Gallagher, Iain J.

    2016-01-01

    The purpose of an F1000 review is to reflect on the bigger picture, exploring controversies and new concepts as well as providing opinion as to what is limiting progress in a particular field. We reviewed about 200 titles published in 2015 that included reference to ‘skeletal muscle, exercise, and ageing’ with the aim of identifying key articles that help progress our understanding or research capacity while identifying methodological issues which represent, in our opinion, major barriers to progress. Loss of neuromuscular function with chronological age impacts on both health and quality of life. We prioritised articles that studied human skeletal muscle within the context of age or exercise and identified new molecular observations that may explain how muscle responds to exercise or age. An important aspect of this short review is perspective: providing a view on the likely ‘size effect’ of a potential mechanism on physiological capacity or ageing. PMID:27303646

  16. In vivo multiphoton tomography in skin aging studies

    NASA Astrophysics Data System (ADS)

    König, Karsten; Bückle, Rainer; Weinigel, Martin; Köhler, Johannes; Elsner, Peter; Kaatz, Martin

    2009-02-01

    High-resolution clinical multiphoton tomography based on the femtosecond laser system DermaInspect has been performed on hundreds of patients and volunteers in Australia, Asia, and Europe. The system enables the in vivo detection of the elastin and the collagen network as well as the imaging of melanin clusters in aging spots. The epidermis-dermis junction can be detected with submicron resolution. One major applications of this novel HighTech imaging tool is the determination of the skin aging index SAAID as well as the study of the effects of anti-aging products. In particular, the stimulated biosynthesis of collagen can be investigated over long periods of time. The system with its sub-500 nm lateral resolution is able to image age-related modifications of the extracellular matrix on the level of a single elastin fiber.

  17. [Age-dependent morphology of human pineal gland: supravital study].

    PubMed

    Ivanov, S V

    2007-01-01

    On the base of analysis of 5784 events of diagnostic magnetic-resonance tomography studies of the head of patients in radio diagnosis departments the database is formed. Only events (n=411) without cerebral, oncology, endocrine and other pathology are taken in database. The material was grouped to time and date of the study, sex and age in accordance with generally accepted categorization. Maximum linear sizes of pineal gland and hypophysis cerebri in sagittal, axial and coronar projection were measured in all events; volumes of the organs were calculated on the formula of a ball. It is defined that the volume of pineal gland increases from birth till 17-21 year age, gradually falls till the second mature age and is getting stable in old age. The normative factors of the volume of pineal gland and hypophysis cerebri for 8 age groups are determined. "Brain sand" and false cysts in pineal gland can be observed in all age groups. The petrification degree of pineal gland, as of computer tomography, varies from 30 to 277 ed. HV. For the factor of pineal gland volume and factor of cysts frequency in pineal gland a puberty "collapse" is typical, mainly in men.

  18. Understanding Nontraditionally Aged College Students: An Exploratory Study

    ERIC Educational Resources Information Center

    Wilson, Julie R.

    2010-01-01

    This dissertation was written in partial fulfillment of the doctoral degree requirements in Counseling Psychology at Capella University. This study was interested in exploring the growing population of nontraditionally aged college students. The purpose of this study was to identify factors that correlated with the academic success of this group…

  19. Zircon U-Pb age of the Pescadero felsite: A late Cretaceous igneous event in the forearc, west-central California Coast Ranges

    USGS Publications Warehouse

    Ernst, W.G.; Martens, U.C.; McLaughlin, R.J.; Clark, J.C.; Moore, Diane E.

    2011-01-01

    Weathered felsite is associated with the late Campanian-Maastrichtian Pigeon Point Formation near Pescadero, California. Poorly exposed, its age and correlation are uncertain. Is it part of the Pigeon Point section west of the San Gregorio-Hosgri fault? Does it rest on Nacimiento block basement? Is it dextrally offset from the Oligocene Cambria Felsite, ~185 km to the southeast? Why is a calc-alkaline hypabyssal igneous rock intrusive into the outboard accretionary prism? To address these questions, we analyzed 43 oscillatory-zoned zircon crystals from three incipiently recrystallized pumpellyite ?? prehnite ?? laumontite-bearing Pescadero felsite samples by sensitive high-resolution ion microprobe-reverse geometry (SHRIMPRG) and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) techniques. Thirty-three zircons gave late Mesozoic U-Pb ages, with single-grain values ranging from 81 to 167 Ma; ten have pre-Mesozoic, chiefl y Proterozoic ages. A group of the four youngest Pescadero zircons yielded an apparent maximum igneous age of ca. 86-90 Ma. Refl ecting broad age scatter and presence of partly digested sandstone inclusions, we interpret the rest of the zircons (perhaps all) as xenocrysts. Twenty-three zircons were separated and analyzed from two samples of the similar Cambria Felsite, yielding a unimodal 27 Ma U-Pb age. Clearly, the origin of the Upper Oligocene Cambria Felsite is different from that of the Upper Cretaceous Pescadero felsite; these rocks are not correlated, and do not constrain displacement along the San Gregorio-Hosgri fault. Peak ages differ slightly, but relative probability curves for Mesozoic and pre-Mesozoic Pescadero zircons compare well, for example, with abundant U-Pb age data for detrital zircons from Franciscan metaclastic strata ~100 km to the east in the Diablo Range- San Francisco Bay area, San Joaquin Great Valley Group turbidites, Upper Cretaceous Nacimiento block Franciscan strata, and Upper Cretaceous

  20. Basin and range-age reactivation of the ancestral Rocky Mountains in Texas Panhandle: evidence from Ogallala Formation

    SciTech Connect

    Budnik, R.T.

    1984-04-01

    The Ogallala Formation (Neogene) is a widespread syntectonic alluvial apron that was shed eastward from the Rio Grande rift and related uplifts in Colorado and New Mexico during Basin and Range extension. In the Texas Panhandle, the Ogallala completely buried Ancestral Rocky Mountain (Pennsylvanian) structures. Renewed movement on these older structures during the Neogene influenced the thickness and facies distribution of the Ogallala. The Ogallala thickens into the Palo Duro, Dalhart, and Anadarko basins. Major distributary channels on Ogallala alluvial fans coincide with the axes of these basins, whereas major interchannel areas overlie intervening uplifts. Second-order structures subtly influenced the unit as well. For example, the Carson basin, a Pennsylvanian rhomb graben along the Amarillo uplift, the Ogallala is over 250 m (820 ft) thick compared with 90 m (275 ft) in adjacent areas. Within the Palo Duro basin, local highs controlled the distribution of thin, interchannel flood-basin and lacustrine deposits. Thicker, braided-stream channel deposits follow local lows. Later movement on the Amarillo uplift broadly folded the Ogallala. The southern high plains surface subtly reflects basement structure, with topographic highs overlying basement highs, suggesting post-Ogallala deformation within the Palo Duro basin. The Amarillo uplift is approximately perpendicular to the Rio Grande rift and parallel to the direction of Basin and Range extension. Thus, the stress field that produced the rift may have caused strike-slip movement and reactivation of the Carson basin along the Amarillo uplift.

  1. High-definition optical coherence tomography intrinsic skin ageing assessment in women: a pilot study.

    PubMed

    Boone, M A L M; Suppa, M; Marneffe, A; Miyamoto, M; Jemec, G B E; Del Marmol, V

    2015-10-01

    Several non-invasive two-dimensional techniques with different lateral resolution and measurable depth range have proved to be useful in assessing and quantifying morphological changes in skin ageing. Among these, only in vivo microscopy techniques permit histometric measurements in vivo. Qualitative and quantitative assessment of chronological (intrinsic) age-related (IAR) morphological changes of epidermis, dermo-epidermal junction (DEJ), papillary dermis (PD), papillary-reticular dermis junction and reticular dermis (RD) have been performed by high-definition optical coherence tomography in real time 3-D. HD-OCT images were taken at the internal site of the right upper arm. Qualitative HD-OCT IAR descriptors were reported at skin surface, at epidermal layer, DEJ, PD and upper RD. Quantitative evaluation of age-related compaction and backscattered intensity or brightness of different skin layers was performed by using the plugin plot z-axis profile of ImageJ(®) software permitting intensity assessment of HD-OCT (DICOM) images (3-D images). Analysis was in blind from all clinical information. Sixty, fair-skinned (Fitzpatrick types I-III) healthy females were analysed retrospectively in this study. The subjects belonged to three age groups: twenty in group I aged 20-39, twenty in group II aged 40-59 and twenty in group III aged 60-79. Only intrinsic ageing in women has been studied. Significant age-related qualitative and quantitative differences could be noticed. IAR changes in dermal matrix fibers morphology/organisation and in microvasculature were observed. The brightness and compaction of the different skin layers increased significantly with intrinsic skin ageing. The depth of visibility of fibers in RD increased significantly in the older age group. In conclusion, HD-OCT allows 3-D in vivo and real time qualitative and quantitative assessment of chronological (intrinsic) age-related morphological skin changes at high resolution from skin surface to a depth

  2. "Aging males" symptoms and general health of adult males: a cross-sectional study.

    PubMed

    Yuen, John W; Ng, Chi-Fai; Chiu, Peter Ka Fung; Teoh, Jeremy Yuen Chun; Yee, C H

    2016-06-01

    A cross-sectional study was conducted to explore the prevalence and severity of health-related complaints perceived by adult males of Hong Kong by using the Hong Kong Traditional Chinese versions of the Aging males' symptoms (AMS) scale and the 5-dimensional and 3-level European Quality of life (EQ-5D-3L) questionnaire. A total of 825 adult males aged 40 years or above were surveyed, and observed that 80% of the population was living with little-to-mild levels of aging symptoms with mean total scores ranged between 26.02 ± 7.91 and 32.99 ± 7.91 in different age groups. Such symptoms were correlated with age, especially for the somato-vegetative and sexual symptoms. The most severe AMS symptoms were observed in the oldest age group at 70 years or above, with 76%, 34% and 70% living with moderate-to-severe levels of somato-vegetative, psychological and sexual symptoms, respectively. The result was highly correlated with the EQ-5D-3L questionnaire. Secondly, the Hong Kong Aging males' symptoms (AMS) scale was shown to have good reliability with test-retest coefficient at 0.79 (ranged 0.66-0.87) and Cronbach's alpha coefficient at 0.88 (ranged 0.70-0.84). In summary, the population of Hong Kong male adults was commonly living with little-to-mild levels of aging symptoms, whereas their severity was correlated with age.

  3. Cumulative Lead Exposure and Age-related Hearing Loss: The VA Normative Aging Study

    PubMed Central

    Park, Sung Kyun; Elmarsafawy, Sahar; Mukherjee, Bhramar; Spiro, Avron; Vokonas, Pantel S.; Nie, Huiling; Weisskopf, Marc G.; Schwartz, Joel; Hu, Howard

    2010-01-01

    Although lead has been associated with hearing loss in occupational settings and in children, little epidemiologic research has been conducted on the impact of cumulative lead exposure on age-related hearing loss in the general population. We determined whether bone lead levels, a marker of cumulative lead exposure, are associated with decreased hearing ability in 448 men from the Normative Aging Study, seen between 1962 and 1996 (2,264 total observations). Air conduction hearing thresholds were measured at 0.25 to 8 kHz and pure tone averages (PTA) (mean of 0.5, 1, 2 and 4 kHz) were computed. Tibia and patella lead levels were measured using K x-ray fluorescence between 1991 and 1996. In cross-sectional analyses, after adjusting for potential confounders including occupational noise, patella lead levels were significantly associated with poorer hearing thresholds at 2, 3, 4, 6 and 8 kHz and PTA. The odds of hearing loss significantly increased with patella lead levels. We also found significant positive associations between tibia lead and the rate change in hearing thresholds at 1, 2, and 8 kHz and PTA in longitudinal analyses. Our results suggest that chronic low-level lead exposure may be an important risk factor for age-related hearing loss and reduction of lead exposure could help prevent or delay development of age-related hearing loss. PMID:20638461

  4. Fluorosilicone and silicone o-ring aging study.

    SciTech Connect

    Bernstein, Robert; Gillen, Kenneth T.

    2007-10-01

    Fluorosilicone o-ring aging studies were performed. These studies examined the compressive force loss of fluorosilicone o-rings at accelerated (elevated) temperatures and were then used to make predictions about force loss at room temperature. The results were non-Arrhenius with evidence for a lowering in Arrhenius activation energies as the aging temperature was reduced. The compression set of these fluorosilicone o-rings was found to have a reasonably linear correlation with the force loss. The aging predictions based on using the observed curvature of the Arrhenius aging plots were validated by field aged o-rings that yielded degradation values reasonably close to the predictions. Compression set studies of silicone o-rings from a previous study resulted in good correlation to the force loss predictions for the fluorosilicone o-rings from this study. This resulted in a preliminary conclusion that an approximately linear correlation exists between compression set and force decay values for typical fluorosilicone and silicone materials, and that the two materials age at similar rates at low temperatures. Interestingly, because of the observed curvature of the Arrhenius plots available from longer-term, lower temperature accelerated exposures, both materials had faster force decay curves (and correspondingly faster buildup of compression set) at room temperature than anticipated from typical high-temperature exposures. A brief study on heavily filled conducting silicone o-rings resulted in data that deviated from the linear relationship, implying that a degree of caution must be exercised about any general statement relating force decay and compression set.

  5. A mixed methods study of age at diagnosis and diagnostic odyssey for Duchenne muscular dystrophy

    PubMed Central

    Wong, Siaw H; McClaren, Belinda J; Archibald, Alison Dalton; Weeks, Alice; Langmaid, Tess; Ryan, Monique M; Kornberg, Andrew; Metcalfe, Sylvia A

    2015-01-01

    The delayed diagnosis of Duchenne muscular dystrophy (DMD) may be an ongoing problem internationally. We aimed to ascertain age at diagnosis and explore parents' experiences of the diagnosis of DMD in Australia. Using mixed methods, data were collected from laboratory and clinical record audits of testing for DMD in Victoria and Tasmania, interviews and a national survey of parents regarding their experiences from first noticing symptoms to receiving a diagnosis. The audits revealed that the median age at diagnosis for DMD was 5 years (n=49 during 2005–2010); this age had not changed substantially over this period. Fourteen parents interviewed reported age at diagnosis ranging from 2 to 8 years with a 6 month to 4 year delay between initial concerns about their child's development and receiving the DMD diagnosis. Sixty-two survey respondents reported the median age at diagnosis was 3 years and 9 months, while the median age when symptoms were noticed was 2 years and 9 months. Parents experienced many emotions in their search for a diagnosis and consulted with a wide range of health professionals. Half the survey respondents felt that their child could have been diagnosed earlier. Despite advances in testing technologies and increasing awareness of DMD, the age at diagnosis has remained constant in Australia. This mixed methods study shows that this diagnostic delay continues to have a negative impact on parents' experiences, places families at risk of having a second affected child and may have a deleterious effect on affected children's treatment. PMID:25626706

  6. The New Mexico aging process study (1979-2003). A longitudinal study of nutrition, health and aging.

    PubMed

    Garry, P J; Wayne, S J; Vellas, B

    2007-01-01

    In 1979, Dr. James S. Goodwin, M.D., assisted by Philip J. Garry, Ph.D., submitted a grant proposal to the United States Public Health Service/ National Institute on Aging (NIA) entitled, "A prospective study of nutrition in the elderly". This study was approved and funded by the NIA beginning in 1979. Initially, approximately 300 men and women over 65 years of age with no known medical illnesses and no prescription medications were selected for this study. The primary purpose of this multi disciplinary study, known in the literature as the New Mexico Aging Process Study (NMAPS), was to examine the role of nutrition and resultant changes in body composition and organ function in relation to the aging process and health status of the elderly. This was accomplished by following prospectively healthy elderly volunteers, obtaining in-depth information about dietary habits, lifestyle, body composition, organ function, cognitive status, vitamin metabolism, genetic markers, and biochemical measures of nutritional status and then examining these data in relationship to age and health status and changes in health status. Some of the specific aims of the study were modified over the course of this longitudinal study because of availability of University of New Mexico School of Medicine faculty with expertise in different areas of aging research. In 1988, Dr. Bruno Vellas from the University Hospital in Toulouse, France became an on-going visiting professor at the University of New Mexico School of Medicine. From 1988, until the study was terminated in 2003, Dr. Vellas has collaborated with the faculty involved in the NMAPS on a number of research projects. In this article, we provide information about the studies overall design and briefly describe some of the major finding of the NMAPS.

  7. Do cherished children age successfully? Longitudinal findings from the Veterans Affairs Normative Aging Study.

    PubMed

    Lee, Lewina O; Aldwin, Carolyn M; Kubzansky, Laura D; Chen, Edith; Mroczek, Daniel K; Wang, Joyce M; Spiro, Avron

    2015-12-01

    Although early adversity has been linked to worse mental and physical health in adulthood, few studies have investigated the pathways through which positive and negative dimensions of early experiences can jointly influence psychological well-being in later life. This study examined: (a) profiles of early experiences across multiple domains, (b) the relations of these profiles to hedonic and eudaimonic well-being in later life, and (c) whether midlife social support mediated these relations. We first conducted latent class analysis of early experiences using data from 1,076 men in the VA Normative Aging Study who completed the Childhood Experiences Scale (age: M = 69, SD = 7). Analyses yielded 3 profiles of early experiences, labeled as cherished (strong support and some losses), harshly disciplined (harsh parental discipline, low positive reinforcement, and nonnormative stressors), and ordinary (few stressors and low parental attention). Next, we applied structural equation modeling to data on a subset of this sample assessed 7 years later on hedonic and eudaimonic well-being (n = 496; age: M = 76, SD = 7). In general, the cherished group reported stronger qualitative social support in midlife than the harshly disciplined and ordinary groups, which in turn was related to greater hedonic (life satisfaction, positive affect) and eudaimonic (competence, positive relations with others) well-being in later life. The cherished group also reported higher autonomy than the ordinary group, but this association was independent of midlife social support. Our findings suggest that experiencing adversity in the context of a nurturing early environment can promote successful aging through the maintenance of supportive relationships in midlife.

  8. Do Cherished Children Age Successfully? Longitudinal Findings from the VA Normative Aging Study

    PubMed Central

    Lee, Lewina O.; Aldwin, Carolyn M.; Kubzansky, Laura D.; Chen, Edith; Mroczek, Daniel K.; Wang, Joyce M.; Spiro, Avron

    2015-01-01

    Although early adversity has been linked to worse mental and physical health in adulthood, few studies have investigated the pathways through which positive and negative dimensions of early experiences can jointly influence psychological well-being in later life. This study examined: (1) profiles of early experiences across multiple domains; (2) the relations of these profiles to hedonic and eudaimonic well-being in later life; and (3) whether midlife social support mediated these relations. We first conducted latent class analysis of early experiences using data from 1,076 men in the VA Normative Aging Study who completed the Childhood Experiences Scale (age: M=69, SD=7). Analyses yielded three profiles of early experiences, labeled as cherished (strong support and some losses), harshly disciplined (harsh parental discipline, low positive reinforcement, and non-normative stressors), and ordinary (few stressors and low parental attention). Next, we applied structural equation modeling to data on a subset of this sample assessed seven years later on hedonic and eudaimonic well-being (n=496; age: M=76, SD=7). In general, the cherished group reported stronger qualitative social support in midlife than the harshly disciplined and ordinary groups, which in turn was related to greater hedonic (life satisfaction, positive affect) and eudaimonic (competence, positive relations with others) well-being in later life. The cherished group also reported higher autonomy than the ordinary group, but this association was independent of midlife social support. Our findings suggest that experiencing adversity in the context of a nurturing early environment can promote successful aging through the maintenance of supportive relationships in midlife. PMID:26436456

  9. Standardising Home Range Studies for Improved Management of the Critically Endangered Black Rhinoceros

    PubMed Central

    Plotz, Roan D.; Grecian, W. James; Kerley, Graham I.H.; Linklater, Wayne L.

    2016-01-01

    Comparisons of recent estimations of home range sizes for the critically endangered black rhinoceros in Hluhluwe-iMfolozi Park (HiP), South Africa, with historical estimates led reports of a substantial (54%) increase, attributed to over-stocking and habitat deterioration that has far-reaching implications for rhino conservation. Other reports, however, suggest the increase is more likely an artefact caused by applying various home range estimators to non-standardised datasets. We collected 1939 locations of 25 black rhino over six years (2004–2009) to estimate annual home ranges and evaluate the hypothesis that they have increased in size. A minimum of 30 and 25 locations were required for accurate 95% MCP estimation of home range of adult rhinos, during the dry and wet seasons respectively. Forty and 55 locations were required for adult female and male annual MCP home ranges, respectively, and 30 locations were necessary for estimating 90% bivariate kernel home ranges accurately. Average annual 95% bivariate kernel home ranges were 20.4 ± 1.2 km2, 53 ±1.9% larger than 95% MCP ranges (9.8 km2 ± 0.9). When home range techniques used during the late-1960s in HiP were applied to our dataset, estimates were similar, indicating that ranges have not changed substantially in 50 years. Inaccurate, non-standardised, home range estimates and their comparison have the potential to mislead black rhino population management. We recommend that more care be taken to collect adequate numbers of rhino locations within standardized time periods (i.e., season or year) and that the comparison of home ranges estimated using dissimilar procedures be avoided. Home range studies of black rhino have been data deficient and procedurally inconsistent. Standardisation of methods is required. PMID:27028728

  10. iPSC technology to study human aging and aging-related disorders.

    PubMed

    Liu, Guang-Hui; Ding, Zhichao; Izpisua Belmonte, Juan Carlos

    2012-12-01

    A global aging population, normally accompanied by a high incidence of aging-associated diseases, has prompted a renewed interest in basic research on human aging. Although encouraging progress has been achieved using animal models, the underlying fundamental mechanisms of aging remain largely unknown. Here, we review the human induced pluripotent stem cell (hiPSC)-based models of aging and aging-related diseases. These models seek to advance our knowledge of aging molecular mechanisms and help to develop strategies for treating aging-associated human diseases.

  11. Studies of the Future Aged. An International Symposium.

    ERIC Educational Resources Information Center

    Friis, Henning; Sheppard, Harold L., Ed.

    These six papers report on future-oriented studies of the situation of the elderly. "Changing Elderly in a Changing Society: Danish Elderly in the Next Century" (Henning Friis) reports on research dealing with preferences of the future elderly for their life when they grow older. "Aging Effectively: Meeting the Challenge of an Aging…

  12. Genotype by Sex and Genotype by Age Interactions with Sedentary Behavior: The Portuguese Healthy Family Study

    PubMed Central

    Santos, Daniel M. V.; Katzmarzyk, Peter T.; Diego, Vincent P.; Blangero, John; Souza, Michele C.; Freitas, Duarte L.; Chaves, Raquel N.; Gomes, Thayse N.; Santos, Fernanda K.; Maia, José A. R.

    2014-01-01

    Sedentary behavior (SB) expression and its underlying causal factors have been progressively studied, as it is a major determinant of decreased health quality. In the present study we applied Genotype x Age (GxAge) and Genotype x Sex (GxSex) interaction methods to determine if the phenotypic expression of different SB traits is influenced by an interaction between genetic architecture and both age and sex. A total of 1345 subjects, comprising 249 fathers, 327 mothers, 334 sons and 325 daughters, from 339 families of The Portuguese Healthy Family Study were included in the analysis. SB traits were assessed by means of a 3-d physical activity recall, the Baecke and IPAQ questionnaires. GxAge and GxSex interactions were analyzed using SOLAR 4.0 software. Sedentary behaviour heritability estimates were not always statistically significant (p>0.05) and ranged from 3% to 27%. The GxSex and GxAge interaction models were significantly better than the single polygenic models for TV (min/day), EEsed (kcal/day), personal computer (PC) usage and physical activty (PA) tertiles. The GxAge model is also significantly better than the polygenic model for Sed (min/day). For EEsed, PA tertiles, PC and Sed, the GxAge interaction was significant because the genetic correlation between SB environments was significantly different from 1. Further, PC and Sed variance heterogeneity among distinct ages were observed. The GxSex interaction was significant for EEsed due to genetic variance heterogeneity between genders and for PC due to a genetic correlation less than 1 across both sexes. Our results suggest that SB expression may be influenced by the interactions between genotype with both sex and age. Further, different sedentary behaviors seem to have distinct genetic architectures and are differentially affected by age and sex. PMID:25302714

  13. A specimen of Paralycoptera Chang & Chou 1977 (Teleostei: Osteoglossoidei) from Hong Kong (China) with a potential Late Jurassic age that extends the temporal and geographical range of the genus

    PubMed Central

    Tse, Tze-Kei; Chang, Mee-mann

    2015-01-01

    We describe a Mesozoic fish Paralycoptera sp. (Teleostei: Osteoglossoidei), on the basis of a postcranial skeleton collected from the volcaniclastic mudstones of the Lai Chi Chong Formation of Hong Kong, China. The new finding—representing the city’s first Mesozoic fish—extends the geographical distribution of Paralycoptera from eastern mainland China into Hong Kong, demonstrating a wider distribution than previously appreciated for this genus. A radiometric age for the Lai Chi Chong Formation of 146.6 ± 0.2 Ma implies a temporal range expansion for Paralycoptera of approximately 40 million years back from the Early Cretaceous (∼110 Ma). However, spores found in the Formation suggest an Early Cretaceous age that is consistent with the existing age assignment to Paralycoptera. We argue that the proposed temporal range extension is genuine because it is based on recent high precision radiometric age data, but given the discrepancies with the biostratigraphic ages further investigation is needed to confirm this. This study provides an important step towards revealing Hong Kong’s Mesozoic vertebrate fauna and understanding its relationship to well-studied mainland Chinese ones. PMID:25834774

  14. A specimen of Paralycoptera Chang & Chou 1977 (Teleostei: Osteoglossoidei) from Hong Kong (China) with a potential Late Jurassic age that extends the temporal and geographical range of the genus.

    PubMed

    Tse, Tze-Kei; Pittman, Michael; Chang, Mee-Mann

    2015-01-01

    We describe a Mesozoic fish Paralycoptera sp. (Teleostei: Osteoglossoidei), on the basis of a postcranial skeleton collected from the volcaniclastic mudstones of the Lai Chi Chong Formation of Hong Kong, China. The new finding-representing the city's first Mesozoic fish-extends the geographical distribution of Paralycoptera from eastern mainland China into Hong Kong, demonstrating a wider distribution than previously appreciated for this genus. A radiometric age for the Lai Chi Chong Formation of 146.6 ± 0.2 Ma implies a temporal range expansion for Paralycoptera of approximately 40 million years back from the Early Cretaceous (∼110 Ma). However, spores found in the Formation suggest an Early Cretaceous age that is consistent with the existing age assignment to Paralycoptera. We argue that the proposed temporal range extension is genuine because it is based on recent high precision radiometric age data, but given the discrepancies with the biostratigraphic ages further investigation is needed to confirm this. This study provides an important step towards revealing Hong Kong's Mesozoic vertebrate fauna and understanding its relationship to well-studied mainland Chinese ones.

  15. Postnatal Foot Length to Determine Gestational Age: A Pilot Study.

    PubMed

    Wyk, Lizelle Van; Smith, Johan

    2016-04-01

    Gestational age is a critical factor in the management, decision-making, prognostication and follow-up of newborn infants. It is also essential for research and epidemiology. In the absence of an early assessment of fetal gestation by abdominal ultrasound, many neonatal units in developing countries determine gestational age by neonatal scores and last menstrual period-both of which are highly inaccurate. The aim of this pilot study was to determine whether postnatal foot length measurement could accurately determine gestational age in a specified South African hospitalized neonatal population. Foot length was measured with a plastic Verniere's caliper. Foot length was shown to correlate well with gestational age (r = 0.919,p < 0.001). Intra-observer and inter-observer variability of foot length measurements was low. Foot length can therefore be used with high accuracy to determine the gestational age in a population where there is poor access to or utilization of antenatal sonar.

  16. Using the accumulation of CBD-extractable iron and clay content to estimate soil age on stable surfaces and nearby slopes, Front Range, Colorado

    NASA Astrophysics Data System (ADS)

    Dethier, David P.; Birkeland, Peter W.; McCarthy, James A.

    2012-11-01

    In many transport-limited environments, morphology, pedogenic iron and clay content provide a basis for estimating the exposure age of soils and associated landforms. We measured citrate-buffered dithionite (CBD)-extractable Fe (Fed) and clay concentration in fresh rock, saprolite, morainal and colluvial materials, and soil horizons from stable surfaces and hillslopes in the Colorado Front Range. Fresh igneous and high-grade metamorphic rocks contain < 1% Fed and 1 to 5% clay. As bedrock and surficial deposits age, Fed and clay accumulate from weathering and dustfall. Late Holocene regolith at warm, dry sites contains small amounts of Fed and clay, but relatively moist soils developed on early Holocene cirque deposits contain as much as 1.5% Fed and 8% clay. Concentrations and total profile accumulation of Fed and clay increase with age in soils developed on stable surfaces of glacial deposits as old as ~ 130 kyr. On stable sites, Fed and clay accumulation from weathering and dust is ~ 0.02 g cm- 2 kyr- 1 and ~ 0.2 g cm- 2 kyr- 1, respectively. We used the Fed and clay inventory in soil profiles at dated, stable Front Range surfaces to calculate accumulation functions, which allowed us to estimate soil age at hillslope sites. Heterogeneous parent material, particularly on hillslopes, and climate-related effects add to variability in measured relations. Mobile regolith in Gordon Gulch, one of the Boulder Creek Critical Zone Observatory (CZO) catchments, yields profile ages from about 0.5 to 5 × 104 yr, comparable to values measured using other techniques. Calculated profile ages are older on a north- vs. south-facing slope and increase from the drainage divide to the footslope. Ages calculated for stabilized colluvium and well-developed buried profiles at nearby hillslope sites (Lefthand, Ward and Rollinsville) suggest that these soils have stabilized over periods > 105 yr. In the absence of radiometric ages, the accumulation of Fed and clay in soils on stable

  17. Do Hassles and Uplifts Change with Age? Longitudinal Findings from the VA Normative Aging Study

    PubMed Central

    Aldwin, Carolyn M.; Jeong, Yu-Jin; Igarashi, Heidi; Spiro, Avron

    2014-01-01

    To examine emotion regulation in later life, we contrasted the modified hedonic treadmill theory with developmental theories, using hassles and uplifts to assess emotion regulation in context. The sample was 1,315 men from the VA Normative Aging Study aged 53 to 85 years, who completed 3,894 observations between 1989 and 2004. We computed three scores for both hassles and uplifts: intensity (ratings reflecting appraisal processes), exposure (count), and summary (total) scores. Growth curves over age showed marked differences in trajectory patterns for intensity and exposure scores. Although exposure to hassles and uplifts decreased in later life, intensity scores increased. Growth based modelling showed individual differences in patterns of hassles and uplifts intensity and exposure, with relative stability in uplifts intensity, normative non-linear changes in hassles intensity, and complex patterns of individual differences in exposure for both hassles and uplifts. Analyses with the summary scores showed that emotion regulation in later life is a function of both developmental change and contextual exposure, with different patterns emerging for hassles and uplifts. Thus, support was found for both hedonic treadmill and developmental change theories, reflecting different aspects of emotion regulation in late life. PMID:24660796

  18. Zebrafish (Danio rerio) as a model for the study of aging and exercise: physical ability and trainability decrease with age.

    PubMed

    Gilbert, Matthew J H; Zerulla, Tanja C; Tierney, Keith B

    2014-02-01

    A rapidly aging global population has motivated the development and use of models for human aging. Studies on aging have shown parallels between zebrafish and humans at the internal organization level; however, few parallels have been studied at the whole-organism level. Furthermore, the effectiveness of exercise as a method to mitigate the effects of aging has not been studied in zebrafish. We investigated the effects of aging and intermittent exercise on swimming performance, kinematics and behavior. Young, middle-aged and old zebrafish (20-29, 36-48 and 60-71% of average lifespan, respectively) were exercised to exhaustion in endurance and sprint swimming tests once a week for four weeks. Both endurance and sprint performance decreased with increased age. Swimming performance improved with exercise training in young and middle-aged zebrafish, but not in old zebrafish. Tail-beat amplitude, which is akin to stride length in humans, increased for all age groups with training. Zebrafish turning frequency, which is an indicator of routine activity, decreased with age but showed no change with exercise. In sum, our results show that zebrafish exhibit a decline in whole-organism performance and trainability with age. These findings closely resemble the senescence-related declines in physical ability experienced by humans and mammalian aging models and therefore support the use of zebrafish as a model for human exercise and aging.

  19. Trade Studies Relating to a Long Range Mach 2.6 Supercruiser

    NASA Technical Reports Server (NTRS)

    Foss, W. E., Jr.; Sorrells, R. B., III

    1978-01-01

    A systems study was conducted on an aircraft concept, representative of a supersonic-cruise military aircraft (supercruiser). The study results indicate that supersonic ranges in excess of 4000 n.mi. at a Mach number of 2.62 are possible with a 500 lbf class aircraft. Trade studies, to determine the sensitivity of supersonic range to parameters which would improve maneuverability, indicate that thrust-weight ratios of as much as 0.5 can be used without significantly decreasing supersonic range; however, increasing the thrust-weight ratio to 1.0 decreases the range capability by about 1100 n.mi. The range penalty for increasing the aircraft limit load-factor from 4.0 to 9.0 is about 500 n.mi. The increased fuel volume of several configurations improved the supersonic range capability by about 1200 n.mi. but, due to associated losses in supersonic L/D, had an insignificant effect on the range at a Mach number of 2.62.

  20. Study of Intermediate Age (~10-30 Myr) Open Clusters

    NASA Astrophysics Data System (ADS)

    Olguin, Lorenzo; Michel, Raul; Contreras, Maria; Hernandez, Jesus; Schuster, William; Chavarria-Kleinhenn, Carlos

    2013-07-01

    We present the study of a sample of intermediate age open clusters (age ~ 10-30 Myr) using optical (UBVRI) and infrared photometric data. Optical photometry was obtained as part of the San Pedro Martir Open Clusters Project (SPM-OCP, Schuster et al. 2007; Michel et al. 2013). Infrared photometry was retrieved from 2MASS public data archive and WISE database. Open clusters included in the SPM-OCP were selected from catalogues presented by Dias et al. (2002) and Froebrich, Scholz & Raftery (2007). One of the main goals of the SPM-OCP is to compile a self-consistent and homogeneous set of cluster fundamental parameters such as reddening, distance, age, and metallicity whenever possible. In this work, we have analyzed a set of 25 clusters from the SPM-OCP with estimated ages between 10 and 30 Myr. Derived fundamental parameters for each cluster in the sample as well as an example of typical color-color and color-magnitude diagrams are presented. Kinematic membership was established by using proper motion data taken from the literature. Based on infrared photometry, we have searched for candidate stars to posses a circumstellar disk within each clusters. For those selected candidates a follow-up spectroscpic study is being carried out. This work was partially supported by UNAM-PAPIIT grant IN-109311.

  1. Age Differences and Changes of Coping Behavior in Three Age Groups: Findings from the Georgia Centenarian Study

    ERIC Educational Resources Information Center

    Martin, Peter; Kliegel, Matthias; Rott, Christoph; Poon, Leonard W.; Johnson, Mary Ann

    2008-01-01

    With increasing age, older adults are more likely to be challenged by an increasing number of physical, functional and social losses. As a result, coping with losses becomes a central theme in very late life. This study investigated age differences and age changes in active behavioral, active cognitive and avoidance coping and related coping to…

  2. Hypoxia and dehydroepiandrosterone in old age: a mouse survival study

    PubMed Central

    Debonneuil, Edouard H; Quillard, Janine; Baulieu, Etienne-Emile

    2006-01-01

    Background Survival remains an issue in pulmonary hypertension, a chronic disorder that often affects aged human adults. In young adult mice and rats, chronic 50% hypoxia (11% FIO2 or 0.5 atm) induces pulmonary hypertension without threatening life. In this framework, oral dehydroepiandrosterone was recently shown to prevent and reverse pulmonary hypertension in rats within a few weeks. To evaluate dehydroepiandrosterone therapy more globally, in the long term and in old age, we investigated whether hypoxia decreases lifespan and whether dehydroepiandrosterone improves survival under hypoxia. Methods 240 C57BL/6 mice were treated, from the age of 21 months until death, by normobaric hypoxia (11% FIO2) or normoxia, both with and without dehydroepiandrosterone sulfate (25 mg/kg in drinking water) (4 groups, N = 60). Survival, pulmonary artery and heart remodeling, weight and blood patterns were assessed. Results In normoxia, control mice reached the median age of 27 months (median survival: 184 days). Hypoxia not only induced cardiopulmonary remodeling and polycythemia in old animals but also induced severe weight loss, trembling behavior and high mortality (p < 0.001, median survival: 38 days). Under hypoxia however, dehydroepiandrosterone not only significantly reduced cardiopulmonary remodeling but also remarkably extended survival (p < 0.01, median survival: 126 days). Weight loss and trembling behavior at least partially remained, and polycythemia completely, the latter possibly favorably participating in blood oxygenation. Interestingly, at the dose used, dehydroepiandrosterone sulfate was detrimental to long-term survival in normoxia (p < 0.05, median survival: 147 days). Conclusion Dehydroepiandrosterone globally reduced what may be called an age-related frailty induced by hypoxic pulmonary hypertension. This interestingly recalls an inverse correlation found in the prospective PAQUID epidemiological study, between dehydroepiandrosterone blood levels and

  3. Dermatological disease in the older age group: a cross-sectional study in aged care facilities

    PubMed Central

    Deo, Maneka S; Vandal, Alain C; Jarrett, Paul

    2015-01-01

    Objectives To estimate the prevalence of dermatological disease in aged care facilities, and the relationship between cognitive or physical disability and significant disease. Setting 2 large aged care facilities in Auckland, New Zealand, each providing low and high level care. Participants All 161 residents of the facilities were invited to participate. The only exclusion criterion was inability to obtain consent from the individual or designated guardian. 88 participants were recruited—66 females (75%), 22 males (25%) with average age 87.1 years (SD 5.5 years). Primary and secondary outcome measures Primary—presence of significant skin disease (defined as that which in the opinion of the investigators needed treatment or was identified as a patient concern) diagnosed clinically on full dermatological examination by a dermatologist or dermatology trainee. Secondary—functional and cognitive status (Rehabilitation Complexity Scale and Abbreviated Mental Test Score). Results 81.8% were found to have at least one significant condition. The most common disorders were onychomycosis 42 (47.7%), basal cell carcinoma 13 (14.8%), asteototic eczema 11 (12.5%) and squamous cell carcinoma in situ 9 (10.2%). Other findings were invasive squamous cell carcinoma 7 (8%), bullous pemphigoid 2 (2.3%), melanoma 2 (2.3%), lichen sclerosus 2 (2.3%) and carcinoma of the breast 1 (1.1%). Inflammatory disease was more common in those with little physical disability compared with those with serious physical disability (OR 3.69; 95% CI 1.1 to 12.6, p=0.04). No significant association was found between skin disease and cognitive impairment. Conclusions A high rate of dermatological disease was found. Findings ranged from frequent but not life-threatening conditions (eg, onychomycosis), to those associated with a significant morbidity (eg, eczema, lichen sclerosus and bullous pemphigoid), to potentially life-threatening (eg, squamous cell carcinoma, melanoma and breast cancer

  4. The Ar-Ar age and petrology of Miller Range 05029: Evidence for a large impact in the very early solar system

    NASA Astrophysics Data System (ADS)

    Weirich, J. R.; Wittmann, A.; Isachsen, C. E.; Rumble, D.; Swindle, T. D.; Kring, D. A.

    2010-12-01

    Miller Range (MIL) 05029 is a slowly cooled melt rock with metal/sulfide depletion and an Ar-Ar age of 4517 ± 11 Ma. Oxygen isotopes and mineral composition indicate that it is an L chondrite impact melt, and a well-equilibrated igneous rock texture with a lack of clasts favors a melt pool over a melt dike as its probable depositional setting. A metallographic cooling rate of approximately 14 °C Ma-1 indicates that the impact occurred at least approximately 20 Ma before the Ar-Ar closure age of 4517 Ma, possibly even shortly after accretion of its parent body. A metal grain with a Widmanstätten-like pattern further substantiates slow cooling. The formation age of MIL 05029 is at least as old as the Ar-Ar age of unshocked L and H chondrites, indicating that endogenous metamorphism on the parent asteroid was still ongoing at the time of impact. Its metallographic cooling rate of approximately 14 °C Ma-1 is similar to that typical for L6 chondrites, suggesting a collisional event on the L chondrite asteroid that produced impact melt at a minimum depth of 5-12 km. The inferred minimum crater diameter of 25-60 km may have shattered the 100-200 km diameter L chondrite asteroid. Therefore, MIL 05029 could record the timing and petrogenetic setting for the observed lack of correlation of cooling rates with metamorphic grades in many L chondrites.

  5. Nothobranchius as a model for aging studies. A review

    PubMed Central

    Lucas-Sánchez, Alejandro; Almaida-Pagán, Pedro Francisco; Mendiola, Pilar; de Costa, Jorge

    2014-01-01

    In recent decades, the increase in human longevity has made it increasingly important to expand our knowledge on aging. To accomplish this, the use of animal models is essential, with the most common being mouse (phylogenetically similar to humans, and a model with a long life expectancy) and Caenorhabditis elegans (an invertebrate with a short life span, but quite removed from us in evolutionary terms). However, some sort of model is needed to bridge the differences between those mentioned above, achieving a balance between phylogenetic distance and life span. Fish of the genus Nothobranchius were suggested 10 years ago as a possible alternative for the study of the aging process. In the meantime, numerous studies have been conducted at different levels: behavioral (including the study of the rest-activity rhythm), populational, histochemical, biochemical and genetic, among others, with very positive results. This review compiles what we know about Nothobranchius to date, and examines its future prospects as a true alternative to the classic models for studies on aging. PMID:25110612

  6. Range of Motion of the Intact Lumbar Segment: A Multivariate Study of 42 Lumbar Spines

    PubMed Central

    Cook, Daniel J.; Yeager, Matthew S.

    2015-01-01

    Background A thorough understanding of the biomechanical characteristics of the healthy human spine is critical in furthering the treatment of spinal pathology. The goal of this study was to investigate the motion of the intact lumbar spine segment as measured by range of motion (ROM), and to investigate the dependencies thereof on gender and intervertebral level. Materials and Methods Kinematic data was obtained for 42 human lumbar segments (L1-S1) in response to a pure-moment loading protocol in flexion extension (FE), lateral bending (LB) and axial torsion (AT). Data was obtained for 204 individual functional spinal units (91 female, 113 male). Multivariate analysis of variance was conducted to detect differences between genders and intervertebral levels in each mode of loading. Correlations between ROM and donor demographics, including height, weight, and age, were conducted. Results ROM was significantly greater for females than for males in FE, LB and AT (p<0.001). ROM tended to increase down the vertebral column in FE. L3-4 FE ROM was significantly greater than L1-2 (p=0.024), and L4-5 and L5-S1 FE ROM were significantly greater than for every other level (p<0.003). LB ROM tended to be greater toward the center of the segment with L2-3, L3-4 and L4-5 ROM being significantly greater than both L1-2 (p<0.001) and L5-S1 (p=0.006, p<0.001, p=0.043, respectively). A similar trend was found for AT, however only L1-2 was significantly less than all other levels (p=0.042, p<0.001, p<0.001, and p=0.034 for L2-3, L3-4, L4-5, and L5-S1 respectively). Conclusion The significant differences in lumbar ROM between male and female spine segments and between the intervertebral levels must be taken into account in study design in order to prevent biases in outcomes. The significant differences in ROM between levels may also have critical implications in the design of spinal implants, particularly those designed to maintain or restore healthy motion. PMID:25785241

  7. A new measure for assessing executive function across a wide age range: children and adults find happy-sad more difficult than day-night.

    PubMed

    Lagattuta, Kristin Hansen; Sayfan, Liat; Monsour, Michael

    2011-05-01

    Two experiments examined 4- to 11-year-olds' and adults' performance (N = 350) on two variants of a Stroop-like card task: the day-night task (say 'day' when shown a moon and 'night' when shown a sun) and a new happy-sad task (say 'happy' for a sad face and 'sad' for a happy face). Experiment 1 featured colored cartoon drawings. In Experiment 2, the happy-sad task featured photographs, and pictures for both measures were gray scale. All age groups made more errors and took longer to respond to the happy-sad versus the day-night versions. Unlike the day-night task, the happy-sad task did not suffer from ceiling effects, even in adults. The happy-sad task provides a methodological advance for measuring executive function across a wide age range.

  8. Immediate Effects of Inhibitive Distraction on Active Range of Cervical Flexion in Patients with Neck Pain: A Pilot Study

    PubMed Central

    Briem, Kristín; Huijbregts, Peter; Thorsteinsdottir, Maria

    2007-01-01

    The purpose of this pilot study was to examine the immediate effects of a manual therapy technique called Inhibitive Distraction (ID) on active range of motion (AROM) for cervical flexion in patients with neck pain with or without concomitant headache. A secondary objective of this study was to see whether patient subgroups could be identified who might benefit more from ID by studying variables such as age, pain intensity, presence of headache, or pre-intervention AROM. We also looked at patients' ability to identify pre- to post-intervention changes in their ability to actively move through a range of motion. Forty subjects (mean age 34.7 years; range 16–48 years) referred to a physical therapy clinic due to discomfort in the neck region were randomly assigned to an experimental and a control group. We used the CROM goniometer to measure pre- and post-intervention cervical flexion AROM in the sagittal plane within a single treatment session. The between-group difference in AROM increase was not statistically significant at P<0.05 with a mean post-intervention increase in ROM of 2.4° (SD 6.2°) for the experimental group and 1.2° (SD 5.8°) for the placebo group. We were also unable to identify potential subgroups more likely to respond to ID, although a trend emerged for greater improvement in chronic patients with headaches, lower pain levels, and less pre-intervention AROM. In the experimental group and in both groups combined, subjects noting increased AROM indeed had a significantly greater increase in AROM than those subjects not noting improvement. In conclusion, this study did not confirm immediate effects of ID on cervical flexion AROM but did provide indications for potential subgroups likely to benefit from this technique. Recommendations are provided with regard to future research and clinical use of the technique studied. PMID:19066648

  9. Note: Long-range scanning tunneling microscope for the study of nanostructures on insulating substrates

    SciTech Connect

    Molina-Mendoza, Aday J.; Rodrigo, José G.; Rubio-Bollinger, Gabino; Island, Joshua; Burzuri, Enrique; Zant, Herre S. J. van der; Agraït, Nicolás

    2014-02-15

    The scanning tunneling microscope (STM) is a powerful tool for studying the electronic properties at the atomic level, however, it is of relatively small scanning range and the fact that it can only operate on conducting samples prevents its application to study heterogeneous samples consisting of conducting and insulating regions. Here we present a long-range scanning tunneling microscope capable of detecting conducting micro and nanostructures on insulating substrates using a technique based on the capacitance between the tip and the sample and performing STM studies.

  10. Phase stability and mechanical properties of c-22 alloy aged in the temperature range 590 to 760 degree c for 16,000 hours

    SciTech Connect

    Edgecumbe Summers, T S; Kumar, M; Mathews, S J; Rebak, R B; Wall, M A

    1998-12-01

    The phase stability of C-22 alloy (UNS #N06022) was studied by aging samples at 593, 649, 704 and 760°C for 2000 h (2.7 mo) and 16,000 h (1.8 yr). The tensile properties and the Charpy impact toughness of these samples were measured in the mill annealed condition as well as after aging. The microstructures of samples aged 16,000 hours were examined using scanning and transmission electron microscopy (SEM and TEM). Preliminary TEM results suggest that m phase forms at all temperatures investigated. Discrete carbide particles in addition to a film with very uniform thickness which appears to be m phase formed on grain boundaries in the sample aged at 593°C. The ordered Ni2(Cr, Mo) phase was also seen in this sample. At the higher aging temperatures, mainly m phase forms covering all the grain boundaries and also distributed throughout the bulk. Although strength increased somewhat with aging, the ductility decreased due to the formation of these grain boundary precipitates and brittle intermetallics.

  11. Phase stability and mechanical properties of C-22 alloy aged in the temperature range 590 to 760 C for 16,000 hours

    SciTech Connect

    Summers, T.S.E.; Wall, M.A.; Kumar, M.; Matthews, S.J.; Rebak, R.B.

    1999-07-01

    The phase stability of C-22 alloy (UNS No. N06022) was studied by aging samples at 593, 649, 704 and 760 C for 2,000 h (2.7 mo) and 16,000 h (1.8 yr). The tensile properties and the Charpy impact toughness of these samples were measured in the mill annealed condition as well as after aging. The microstructures of samples aged 16,000 hours were examined using scanning and transmission electron microscopy (SEM and TEM). Preliminary TEM results suggest that {mu} phase forms at all temperatures investigated. Discrete carbide particles in addition to a film with very uniform thickness which appears to be {mu} phase formed on grain boundaries in the sample aged at 593 C. The ordered Ni{sub 2}(Cr, Mo) phase was also seen in this sample. At the higher aging temperatures, mainly {mu} phase forms covering all the grain boundaries and also distributed throughout the bulk. Although strength increased somewhat with aging, the ductility decreased due to the formation of these grain boundary precipitates and brittle intermetallics.

  12. Ar/Ar and U/Pb Ages and Geochemistry of the Benton Range Dike Swarm, SE California: New Evidence for an Independence Poly-phased Dike Swarm

    NASA Astrophysics Data System (ADS)

    Jourdan, F.; Renne, P. R.; Mundil, R.

    2005-12-01

    The Independence dike swarm (IDS) is a locally profuse, mostly NNW striking and ~700 km-long dike swarm occurring throughout southeastern California and possibly extending into northern Mexico. Dike compositions range from mafic to silicic (though strongly bimodal) and span the composition range of the coeval Sierran calc-alkaline arc plutons. Recent geochronological and structural investigations had cast some doubt on the accurate definition of the Independence dike swarm as the swarm more likely represents a poly-phase dike assemblage including at least two generation of dikes (i.e. 90 and 150 Ma; Chen and Moore, 1979; Coleman et al., 2000). To date, most of the geochronological and geochemical investigations available are strongly localized and part of the swarm lacks basic data. Here, we present new 40Ar39Ar (n=4) and U/Pb (n=1) ages and detailed major, trace and REE geochemical data on mafic (E-W to N-S) and more abundant silicic (NW-SE to N-S) dikes from the Benton Range dike swarm (BRDS), north-easternmost IDS. Two of the silicic dikes yielded concordant biotite 40Ar39Ar mini-plateau and weighted mean ages of 153 ± 2 and 152 ± 3 Ma (2 sigma), in agreement with previous K-Ar biotite ages of 150-155 Ma (Renne et al., 1987) and similar to the "accepted" age for the Independence swarm (~150 Ma). These biotite ages, however, may record a cooling age that significantly post-dates dike intrusion. One silicic dike yields a significantly older, preliminary 206Pb238U zircon age of 164.6 ± 0.8 Ma from single-crystal analyses. Two E-W striking mafic dikes which cross-cut NNW-striking silicic dikes yield hornblende plateau and mini-plateau ages of 171 ± 2 and 166 ± 2 Ma. BRDS chemical compositions are typical of mafic (SiO2 = 47-57 wt%; La/Ybn = 3-14) and granitic (SiO2 =67-77 wt%; La/Ybn = 5-31) arc magmas (e.g. Nb anomaly) and typify the known end-member compositions of the IDS. These results, together with compilated published and unpublished geochronological and

  13. Microbiota and healthy ageing: observational and nutritional intervention studies.

    PubMed

    Brüssow, Harald

    2013-07-01

    Hundred years ago Metchnikoff associated human health and particularly healthy ageing with a specific type of gut microbiota. Classical culture methods associated a decrease in bifidobacteria and an increase in enterobacteria with ageing. Modern molecular methods blurred this simple picture and documented a substantial inter-individual variability for the gut microbiome even when stratifying the elderly subjects according to health status. Nutritional interventions with resistant starch showed consistent gut microbiota changes across studies from different geographical areas and prebiotic supplementation induced a 10-fold increase in gut bifidobacteria. However, in the ELDERMET study, microbiota changes do not precede, but follow the changes in health status of elderly subjects possibly as a consequence of diet changes.

  14. Online aging study of a high rate MRPC

    NASA Astrophysics Data System (ADS)

    Wang, Jie; Wang, Yi; Feng, S. Q.; Xie, Bo; Lv, Pengfei; Wang, Fuyue; Guo, Baohong; Han, Dong; Li, Yuanjing

    2016-05-01

    With the constant increase of accelerator luminosity, the rate requirements of MRPC detectors have become very important, and the aging characteristics of the detector have to be studied meticulously. An online aging test system has been set up in our lab, and in this paper the setup of the system is described and the performance stability of a high-rate MRPC studied over a long running time under a high luminosity environment. The high rate MRPC was irradiated by X-rays for 36 days and the accumulated charge density reached 0.1 C/cm2. No obvious performance degradation was observed for the detector. Supported by National Natural Science Foundation of China (11420101004, 11461141011, 11275108), Ministry of Science and Technology (2015CB856905)

  15. Successful aging at work: an applied study of selection, optimization, and compensation through impression management.

    PubMed

    Abraham, J D; Hansson, R O

    1995-03-01

    Although many abilities basic to human performance appear to decrease with age, research has shown that job performance does not generally show comparable declines. Baltes and Baltes (1990) have proposed a model of successful aging involving Selection, Optimization, and Compensation (SOC), that may help explain how individuals maintain important competencies despite age-related losses. In the present study, involving a total of 224 working adults ranging in age from 40 to 69 years, occupational measures of Selection, Optimization, and Compensation through impression management (Compensation-IM) were developed. The three measures were factorially distinct and reliable (Cronbach's alpha > .80). Moderated regression analyses indicated that: (1) the relationship between Selection and self-reported ability/performance maintenance increased with age (p < or = .05); and (2) the relationship between both Optimization and Compensation-IM and goal attainment (i.e., importance-weighted ability/performance maintenance) increased with age (p < or = .05). Results suggest that the SOC model of successful aging may be useful in explaining how older workers can maintain important job competencies. Correlational evidence also suggests, however, that characteristics of the job, workplace, and individual may mediate the initiation and effectiveness of SOC behaviors.

  16. Forensic age diagnostics using projection radiography of the clavicle: a prospective multi-center validation study.

    PubMed

    Wittschieber, Daniel; Ottow, Christian; Schulz, Ronald; Püschel, Klaus; Bajanowski, Thomas; Ramsthaler, Frank; Pfeiffer, Heidi; Vieth, Volker; Schmidt, Sven; Schmeling, Andreas

    2016-01-01

    The radiological investigation of the ossification stage of the medial clavicular epiphysis represents the crucial tool for assessing whether a living individual has completed the age of 18 years. However, exposure to radiation cannot always be accepted due to legal reasons and radiation-free methods still lack reference data or are not available. Therefore, this study examines the role of pre-existing radiographic material of the clavicles, making it necessary to prospectively validate the established five-stage classification system for evaluating the clavicular ossification process as well as to enlarge the so far very limited pool of available reference data. Accordingly, standard posterior-anterior projection radiographs of 836 sternoclavicular joints prospectively obtained during 418 forensic autopsies (age range 15-30 years) were analyzed. Stage III was first found at ages 16 and 15 (males/females), stage IV at ages 22 and 21 (males/females), and stage V at age 26 in both sexes. The presented results principally corroborate the previous reference data from 2004, suggesting reliability of the five-stage classification system. In conclusion, chest radiographs may still be useful for forensic age diagnostics in living individuals but only in certain cases. In age estimations which can be planned in advance, projection radiography of the clavicle must still be considered obsolete.

  17. Early Neurodevelopmental Findings Predict School Age Cognitive Abilities in Duchenne Muscular Dystrophy: A Longitudinal Study

    PubMed Central

    Chieffo, Daniela; Brogna, Claudia; Berardinelli, Angela; D’Angelo, Grazia; Mallardi, Maria; D’Amico, Adele; Alfieri, Paolo; Mercuri, Eugenio; Pane, Marika

    2015-01-01

    Objective Neurodevelopmental and cognitive difficulties are known to occur frequently in boys with Duchenne muscular dystrophy but so far none of the published studies have reported both early neurodevelopmental assessments and cognitive tests in the same cohort. The aim of the present longitudinal study was to establish the correlation between early neurodevelopmental assessments performed in preschool boys and the cognitive scales performed at school age or later. Methods We performed cognitive tests at school age (mean age 5.7 year ±1.7 SD) (69 months+19 SD) in a cohort of Duchenne boys, previously assessed using the Griffiths scales before the age of 4 years (mean age when the Griffiths scales were performed 30 months ±8.9 SD). Results The range of total Developmental quotients on the Griffiths ranged between 56 and 116 (mean 89 ± 15.6 SD). The total Intelligence Quotients on the Wechsler scales ranged between 35 and 119 (mean 87 ± 17.2 SD). There was a significant correlation between the findings on the two scales. P = <0.0001. When we subdivided the cohort according to site of mutations, there was a difference between boys with mutations upstream exon 44 and those with mutations in exon 44–45 affecting Dp140 on both Developmental and Intelligence Quotient (p 0.01 and p 0,003 respectively). Conclusions Our results confirm that Duchenne boys tend to slightly underperform on both neurodevelopmental and cognitive assessments. Early neurodevelopmental findings correlated with the cognitive results obtained at school age with a clear concordance between subscales exploring similar domains on the two scales. PMID:26275215

  18. Twins for epigenetic studies of human aging and development.

    PubMed

    Tan, Qihua; Christiansen, Lene; Thomassen, Mads; Kruse, Torben A; Christensen, Kaare

    2013-01-01

    Most of the complex traits including aging phenotypes are caused by the interaction between genome and environmental conditions and the interface of epigenetics may be a central mechanism. Although modern technologies allow us high-throughput profiling of epigenetic patterns already at genome level, our understanding of genetic and environmental influences on the epigenetic processes remains limited. Twins are of special interest for genetic studies due to their genetic similarity and rearing-environment sharing. The classical twin design has made a great contribution in dissecting the genetic and environmental contributions to human diseases and complex traits. In the era of functional genomics, the valuable sample of twins is helping to bridge the gap between gene activity and the environments through epigenetic mechanisms unlimited by DNA sequence variations. We propose to extend the classical twin design to study the aging-related molecular epigenetic phenotypes and link them with environmental exposures especially early life events. Different study designs and application issues will be highlighted and novel approaches introduced with aim at making uses of twins in assessing the environmental impact on epigenetic changes during development and in the aging process.

  19. Social activity and healthy aging: a study of aging Danish twins.

    PubMed

    McGue, Matt; Christensen, Kaare

    2007-04-01

    Although social and intellectual engagement have been consistently associated with late-life functioning, rather than true causation, these associations may reflect the experiential choices of high functioning individuals (i.e., selection effects). We investigated the association of social activity with late-life physical functioning, cognitive functioning, and depression symptomatology using data from 1112 pairs of like-sex twins who participated in the Longitudinal Study of Aging Danish Twins. Consistent with previous research, we found that social activity was significantly correlated with overall level of physical functioning, cognitive functioning, and depression symptomatology. We also found that social activity was significantly and moderately heritable (estimate of .36), raising the possibility that its association with late-life functioning might reflect selection processes. Further, social activity did not predict change in functioning and in monozygotic twin pairs discordant on level of social activity, the more socially active twin was not less susceptible to age decreases in physical and cognitive functioning and increases in depression symptomatology than the less socially active twin. These results are interpreted in the context of the additional finding that nonshared environmental factors, although apparently not social activity, are the predominant determinant of changes in late-life functioning.

  20. Extended dynamical mean-field study of the Hubbard model with long-range interactions

    NASA Astrophysics Data System (ADS)

    Huang, Li; Ayral, Thomas; Biermann, Silke; Werner, Philipp

    2014-11-01

    Using extended dynamical mean-field theory and its combination with the G W approximation, we compute the phase diagrams and local spectral functions of the single-band extended Hubbard model on the square and simple cubic lattices, considering long-range interactions up to the third nearest neighbors. The longer-range interactions shift the boundaries between the metallic, charge-ordered insulating, and Mott insulating phases, and lead to characteristic changes in the screening modes and local spectral functions. Momentum-dependent self-energy contributions enhance the correlation effects and thus compete with the additional screening effect from longer-range Coulomb interactions. Our results suggest that the influence of longer-range intersite interactions is significant, and that these effects deserve attention in realistic studies of correlated materials.

  1. Genomewide association study for onset age in Parkinson disease

    PubMed Central

    Latourelle, Jeanne C; Pankratz, Nathan; Dumitriu, Alexandra; Wilk, Jemma B; Goldwurm, Stefano; Pezzoli, Gianni; Mariani, Claudio B; DeStefano, Anita L; Halter, Cheryl; Gusella, James F; Nichols, William C; Myers, Richard H; Foroud, Tatiana

    2009-01-01

    Background Age at onset in Parkinson disease (PD) is a highly heritable quantitative trait for which a significant genetic influence is supported by multiple segregation analyses. Because genes associated with onset age may represent invaluable therapeutic targets to delay the disease, we sought to identify such genetic modifiers using a genomewide association study in familial PD. There have been previous genomewide association studies (GWAS) to identify genes influencing PD susceptibility, but this is the first to identify genes contributing to the variation in onset age. Methods Initial analyses were performed using genotypes generated with the Illumina HumanCNV370Duo array in a sample of 857 unrelated, familial PD cases. Subsequently, a meta-analysis of imputed SNPs was performed combining the familial PD data with that from a previous GWAS of 440 idiopathic PD cases. The SNPs from the meta-analysis with the lowest p-values and consistency in the direction of effect for onset age were then genotyped in a replication sample of 747 idiopathic PD cases from the Parkinson Institute Biobank of Milan, Italy. Results Meta-analysis across the three studies detected consistent association (p < 1 × 10-5) with five SNPs, none of which reached genomewide significance. On chromosome 11, the SNP with the lowest p-value (rs10767971; p = 5.4 × 10-7) lies between the genes QSER1 and PRRG4. Near the PARK3 linkage region on chromosome 2p13, association was observed with a SNP (rs7577851; p = 8.7 × 10-6) which lies in an intron of the AAK1 gene. This gene is closely related to GAK, identified as a possible PD susceptibility gene in the GWAS of the familial PD cases. Conclusion Taken together, these results suggest an influence of genes involved in endocytosis and lysosomal sorting in PD pathogenesis. PMID:19772629

  2. Intellectual functioning in old and very old age: cross-sectional results from the Berlin Aging Study.

    PubMed

    Lindenberger, U; Baltes, P B

    1997-09-01

    This study documents age trends, interrelations, and correlates of intellectual abilities in old and very old age (70-103 years) from the Berlin Aging Study (N = 516). Fourteen tests were used to assess 5 abilities: reasoning, memory, and perceptual speed from the mechanic (broad fluid) domain and knowledge and fluency from the pragmatic (broad crystallized) domain. Intellectual abilities had negative linear age relations, with more pronounced age reductions in mechanic than in pragmatic abilities. Interrelations among intellectual abilities were highly positive and did not follow the mechanic-pragmatic distinction. Sociobiographical indicators were less closely linked to intellectual functioning than sensory-sensorimotor variables, which predicted 59% of the total reliable variance in general intelligence. Results suggest that aging-induced biological factors are a prominent source of individual differences in intelligence in old and very old age.

  3. The human trochlear and abducens nerves at different ages - a morphometric study.

    PubMed

    Ramkumar, Muthu; Sharma, Saroj; Jacob, Tony G; Bhardwaj, Daya N; Nag, Tapas C; Roy, Tara Sankar

    2015-02-01

    The trochlear and abducens nerves (TN and AN) control the movement of the superior oblique and lateral rectus muscles of the eyeball, respectively. Despite their immense clinical and radiological importance no morphometric data was available from a wide spectrum of age groups for comparison with either pathological or other conditions involving these nerves. In the present study, morphometry of the TN and AN was performed on twenty post-mortem samples ranging from 12-90 years of age. The nerve samples were processed for resin embedding and toluidine blue stained thin (1µm) sections were used for estimating the total number of myelinated axons by fractionator and the cross sectional area of the nerve and the axons by point counting methods. We observed that the TN was covered by a well-defined epineurium and had ill-defined fascicles, whereas the AN had multiple fascicles with scanty epineurium. Both nerves contained myelinated and unmyelinated fibers of various sizes intermingled with each other. Out of the four age groups (12-20y, 21-40y, 41-60y and >61y) the younger groups revealed isolated bundles of small thinly myelinated axons. The total number of myelinated fibers in the TN and AN at various ages ranged from 1100-3000 and 1600-7000, respectively. There was no significant change in the cross-sectional area of the nerves or the axonal area of the myelinated nerves across the age groups. However, myelin thickness increased significantly in the AN with aging (one way ANOVA). The present study provides baseline morphometric data on the human TN and AN at various ages.

  4. Effects of intrinsic aging and photodamage on skin dyspigmentation: an explorative study

    NASA Astrophysics Data System (ADS)

    Dobos, Gabor; Trojahn, Carina; D'Alessandro, Brian; Patwardhan, Sachin; Canfield, Douglas; Blume-Peytavi, Ulrike; Kottner, Jan

    2016-06-01

    Photoaging is associated with increasing pigmentary heterogeneity and darkening of skin color. However, little is known about age-related changes in skin pigmentation on sun-protected areas. The aim of this explorative study was to measure skin color and dyspigmentation using image processing and to evaluate the reliability of these parameters. Twenty-four volunteers of three age-groups were included in this explorative study. Measurements were conducted at sun-exposed and sun-protected areas. Overall skin-color estimates were similar among age groups. The hyper- and hypopigmentation indices differed significantly by age groups and their correlations with age ranged between 0.61 and 0.74. Dorsal forearm skin differed from the other investigational areas (p<0.001). We observed an increase in dyspigmentation at all skin areas, including sun-protected skin areas, already in young adulthood. Associations between age and dyspigmentation estimates were higher compared to color parameters. All color and dyspigmentation estimates showed high reliability. Dyspigmentation parameters seem to be better biomarkers for UV damage than the overall color measurements.

  5. Parental Predictors of Children's Shame and Guilt at Age 6 in a Multimethod, Longitudinal Study.

    PubMed

    Parisette-Sparks, Alyssa; Bufferd, Sara J; Klein, Daniel N

    2015-11-04

    Shame and guilt are self-conscious emotions that begin to develop early in life and are associated with various forms of psychopathology. However, little is known about the factors that contribute to these emotions in young children. Specifically, no longitudinal studies to date have examined a range of parent factors that shape the expression of children's shame and guilt. The current multimethod, longitudinal study sought to determine whether parenting style, parental psychopathology, and parents' marital satisfaction assessed when children were age 3 predict expressions of shame and guilt in children at age 6. A large community sample of families (N = 446; 87.4% Caucasian) with 3-year-old children (45.7% female) was recruited through commercial mailing lists. Parent variables were assessed when children were age 3 with mother- and father-report questionnaires and a diagnostic interview. Children's expressions of shame and guilt were observed in the laboratory at age 6. Fathers', but not mothers', history of depression and permissive parenting assessed when children were age 3 predicted children's expressions of shame and guilt when children were age 6; parents' marital dissatisfaction also predicted children's shame and guilt. These findings suggest that parents, and fathers in particular, contribute to expressions of self-conscious emotions in children. These data on emotional development may be useful for better characterizing the risk and developmental pathways of psychopathology.

  6. Light scattering study of the normal human eye lens: Elastic properties and age dependence

    PubMed Central

    Bailey, Sheldon T.; Twa, Michael D.; Gump, Jared C.; Venkiteshwar, Manoj; Bullimore, Mark A.

    2015-01-01

    The human ocular lens is a tissue capable of changing its shape to dynamically adjust the optical power of the eye, a function known as accommodation, which gradually declines with age. This capability is the response of the lens tissue to external forces which, in turn, is modulated by the biomechanical characteristics of lens tissues. In order to investigate the contributions of lens sclerosis to loss of accommodation, we report on in vitro confocal Brillouin light scattering studies of human ocular lenses spanning over a 30-70 year age range. Using this non-destructive measurement method, we determined that the longitudinal bulk modulus (average ± SD) of the lens nucleus (2.79±0.14 GPa) was consistently greater than the bulk modulus of the lens cortex (2.36±0.09 GPa). Moreover, our results showed that these differences were not age dependent over the 40 year age range that we evaluated using healthy lens tissues. Our results are consistent with the hypothesis that an age-dependent change in the bulk modulus of lens tissues does not fully account for the natural decline of accommodation. PMID:20529725

  7. Denver RTD range extension study. Task 2 - system definitions. Task 3 - system assessments. Working paper

    SciTech Connect

    Not Available

    1982-05-01

    This working paper presents the results obtained in Task 2: System Definition and Task 3: System Assessments of the Battery-Electric Bus Range Extension Study of the Denver Regional Transit District (RTD) study. The buses were tested on the following range extension techniques: baseline system battery exchange; hydro-pneumatic regeneration system to recover braking energy; fast recharge at the Mall terminals; series hybrid: on-board internal combustion engine and generator which charges the battery; and combination of hydro-pneumatic regeneration and fast recharge at the Mall terminals.

  8. A Genome-Wide Association Study of Aging

    PubMed Central

    Walter, Stefan; Atzmon, Gil; Demerath, Ellen W.; Garcia, Melissa E.; Kaplan, Robert C.; Kumari, Meena; Lunetta, Kathryn L.; Milaneschi, Yuri; Tanaka, Toshiko; Tranah, Gregory J.; Völker, Uwe; Yu, Lei; Arnold, Alice; Benjamin, Emelia J.; Biffar, Reiner; Buchman, Aron S.; Boerwinkle, Eric; Couper, David; De Jager, Philip L.; Evans, Denis A.; Harris, Tamara B.; Hoffmann, Wolfgang; Hofman, Albert; Karasik, David; Kiel, Douglas P.; Kocher, Thomas; Kuningas, Maris; Launer, Lenore J.; Lohman, Kurt K.; Lutsey, Pamela L.; Mackenbach, Johan; Marciante, Kristin; Psaty, Bruce M.; Reiman, Eric M.; Rotter, Jerome I.; Seshadri, Sudha; Shardell, Michelle D.; Smith, Albert V.; van Duijn, Cornelia; Walston, Jeremy; Zillikens, M. Carola; Bandinelli, Stefania; Baumeister, Sebastian E.; Bennett, David A.; Ferrucci, Luigi; Gudnason, Vilmundur; Kivimaki, Mika; Liu, Yongmei; Murabito, Joanne M.; Newman, Anne B.; Tiemeier, Henning; Franceschini, Nora

    2011-01-01

    Human longevity and healthy aging show moderate heritability (20–50%). We conducted a meta-analysis of genome-wide association studies from nine studies from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium for two outcomes: a) all-cause mortality and b) survival free of major disease or death. No single nucleotide polymorphism (SNP) was a genome-wide significant predictor of either outcome (p < 5 × 10−8). We found fourteen independent SNPs that predicted risk of death, and eight SNPs that predicted event-free survival (p < 10−5). These SNPs are in or near genes that are highly expressed in the brain (HECW2, HIP1, BIN2, GRIA1), genes involved in neural development and function (KCNQ4, LMO4, GRIA1, NETO1) and autophagy (ATG4C), and genes that are associated with risk of various diseases including cancer and Alzheimer’s disease. In addition to considerable overlap between the traits, pathway and network analysis corroborated these findings. These findings indicate that variation in genes involved in neurological processes may be an important factor in regulating aging free of major disease and achieving longevity. PMID:21782286

  9. A genome-wide association study of aging.

    PubMed

    Walter, Stefan; Atzmon, Gil; Demerath, Ellen W; Garcia, Melissa E; Kaplan, Robert C; Kumari, Meena; Lunetta, Kathryn L; Milaneschi, Yuri; Tanaka, Toshiko; Tranah, Gregory J; Völker, Uwe; Yu, Lei; Arnold, Alice; Benjamin, Emelia J; Biffar, Reiner; Buchman, Aron S; Boerwinkle, Eric; Couper, David; De Jager, Philip L; Evans, Denis A; Harris, Tamara B; Hoffmann, Wolfgang; Hofman, Albert; Karasik, David; Kiel, Douglas P; Kocher, Thomas; Kuningas, Maris; Launer, Lenore J; Lohman, Kurt K; Lutsey, Pamela L; Mackenbach, Johan; Marciante, Kristin; Psaty, Bruce M; Reiman, Eric M; Rotter, Jerome I; Seshadri, Sudha; Shardell, Michelle D; Smith, Albert V; van Duijn, Cornelia; Walston, Jeremy; Zillikens, M Carola; Bandinelli, Stefania; Baumeister, Sebastian E; Bennett, David A; Ferrucci, Luigi; Gudnason, Vilmundur; Kivimaki, Mika; Liu, Yongmei; Murabito, Joanne M; Newman, Anne B; Tiemeier, Henning; Franceschini, Nora

    2011-11-01

    Human longevity and healthy aging show moderate heritability (20%-50%). We conducted a meta-analysis of genome-wide association studies from 9 studies from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium for 2 outcomes: (1) all-cause mortality, and (2) survival free of major disease or death. No single nucleotide polymorphism (SNP) was a genome-wide significant predictor of either outcome (p < 5 × 10(-8)). We found 14 independent SNPs that predicted risk of death, and 8 SNPs that predicted event-free survival (p < 10(-5)). These SNPs are in or near genes that are highly expressed in the brain (HECW2, HIP1, BIN2, GRIA1), genes involved in neural development and function (KCNQ4, LMO4, GRIA1, NETO1) and autophagy (ATG4C), and genes that are associated with risk of various diseases including cancer and Alzheimer's disease. In addition to considerable overlap between the traits, pathway and network analysis corroborated these findings. These findings indicate that variation in genes involved in neurological processes may be an important factor in regulating aging free of major disease and achieving longevity.

  10. [Stuttering in preschool age: a survey of studies].

    PubMed

    Tarkowski, Zbigniew; Humeniuk, Ewa; Dunaj, Jolanta

    2010-01-01

    Most often stuttering is identified with a speech disorder or speech disfluency. However, it resembles a disorder consisting of linguistic, biological, psychological and social factors, as well as relations between them. The onset of stuttering usually occurs in the preschool age or even earlier, though relatively little concern has been devoted to this period. The article presents a review of the latest research on stuttering in preschool age. A distinct disproportion between particular elements of stuttering structure have been observed. Research concerns mainly the linguistic factor and is focused on speech disfluency, while studies on the biological, psychological and social factors are insufficient. Research on relations between them is rare. Despite efforts of a number of researchers, differential diagnosis of preschool stuttering and natural speech disfluency is still controversial, as is early therapeutic intervention. In research it is usually omitted that the essence of speech disfluency is its changeability. It continually appears and disappears. The causes of this mysterious phenomenon are still unknown.

  11. Ferrocyanide Safety Project: Subtask 3. 4, Aging Studies

    SciTech Connect

    Lilga, M.A.; Lumetta, M.R.; Riemath, W.F.; Romine, R.A.; Schiefelbein, G.F.

    1992-11-01

    The Hanford Ferrocyanide Task Team is addressing issues involving ferrocyanide precipitates in single-shell waste storage tanks (SSTs), in particular the storage of waste in a safe manner. This Task Team, composed of researchers from Westinghouse Hanford Company (WHC), Pacific Northwest Laboratory (PNL), and outside consultants, was formed in response to the need for an updated analysis of safety questions about the Hanford ferrocyanide tanks. This annual report gives the results of the work conducted by PNL in FY 1992 on Subtask 3.4, Aging Studies, which is part of Task 3, Chemical Nature of Feffocyanide in Wastes. Subtask 3.4 deals with the aging behavior and solubilization of ferrocyanide tank waste sludges in a basic aqueous environment. Investigated were the effects of pH variation, ionic strength, salts present in SSTS, and gamma radiation on solubilization of vendor-prepared Na[sub 2]NiFe(CN)[sub 6].

  12. A systemic-wholistic approach to differential aging: longitudinal findings from the Berlin Aging Study.

    PubMed

    Gerstorf, Denis; Smith, Jacqui; Baltes, Paul B

    2006-12-01

    Wholistic perspectives on differential change focus on multiple-indicator information at a person level. They supplement the modeling of average trajectories at a variable level. The authors extended cross-sectional work in the Berlin Aging Study (J. Smith & P. B. Baltes, 1997) to 6-year longitudinal cluster analyses (n = 132). At baseline, 3 subgroups were identified with distinct within-person psychological profiles across cognitive, personality, and social integration constructs. Over time, highly similar subgroup profiles were found, and about two thirds of the participants could be classified as remaining in the same subgroups. Baseline subgroups differed in level and slope of change and in 2 outcomes, well-being and mortality. Independent of subgroup membership, subgroup-to-subgroup change was associated with greater decline and predicted poststudy mortality. These findings demonstrate the usefulness of a wholistic approach for long-term prediction of outcomes and within-person systemic variability.

  13. Age dependence of dielectric properties of bovine brain and ocular tissues in the frequency range of 400 MHz to 18 GHz

    NASA Astrophysics Data System (ADS)

    Schmid, Gernot; Überbacher, Richard

    2005-10-01

    In order to identify possible age-dependent dielectric properties of brain and eye tissues in the frequency range of 400 MHz to 18 GHz, measurements on bovine grey and white matter as well as on cornea, lens (cortical) and the vitreous body were performed using a commercially available open-ended coaxial probe and a computer-controlled vector network analyser. Freshly excised tissues of 52 animals of two age groups (42 adult animals, i.e. 16-24 month old and 10 young animals, i.e. 4-6 month old calves) were examined within 8 min (brain tissue) and 15 min (eye tissue), respectively, of the animals' death. Tissue temperatures for the measurements were 32 ± 1 °C and 25 ± 1 °C for brain and eye tissues, respectively. Statistical analysis of the measured data revealed significant differences in the dielectric properties of white matter and cortical lens tissue between the adult and the young group. In the case of white matter the mean values of conductivity and permittivity of young tissue were 15%-22% and 12%-15%, respectively, higher compared to the adult tissue in the considered frequency range. Similarly, young cortical lens tissue was 25%-76% higher in conductivity and 27%-39% higher in permittivity than adult cortical lens tissue.

  14. Tumor-Specific D-Dimer Concentration Ranges and Influencing Factors: A Cross-Sectional Study

    PubMed Central

    Lei, Dansheng; Yuan, Feng; Pei, Feng; Zhang, Huifeng; Yu, Anming; Wang, Kun; Chen, Hu; Chen, Liang; Wu, Xianglei; Tong, Xianli; Wang, Yefu

    2016-01-01

    D-dimer level in cancer patients is associated with risk of venous thromboembolism and deep venous thrombosis. Most cancer patients have “abnormal” D-dimer levels based on the current normal reference range. To investigate tumor-specific D-dimer reference range, we compared D-dimer levels for nine different tumour types with healthy controls by using simultaneous quantile regression and constructing a median, 5th percentile, and 95th percentile model of normal tumour D-dimer concentration. Associations with tumour primary site, stage, pathological type, and treatment were also explored. Additionally, 190 patients were tracked to reveal the relevance of initial D-dimer levels to cancer prognosis. D-dimer ranges (median, 5th, 95th) in various cancers (mg/L) were: liver 1.12, 0.27, 5.25; pancreatic 0.96, 0.23, 4.81; breast 0.44, 0.2, 2.17; gastric 0.65, 0.22, 5.03; colorectal 0.73, 0.22, 4.45; lung 0.7, 0.25, 4.0; gynaecological 0.61, 0.22, 3.98; oesophageal 0.23, 0.7, 3.45; and head and neck 0.22, 0.44, 2.19. All were significantly higher than that of healthy controls (0.18, 0.07, 0.57). D-dimer peaked 1–2 days postoperatively but had decreased to the normal range by 1 week. Additionally, cancer patients with high initial D-dimer were shown a tendency of poor prognosis in survival rate. In conclusion, D-dimer levels in cancer depend on patient age, tumour primary site, and tumour stage. Thrombosis prevention is necessary if D-dimer has not decreased to the tumor-specific baseline a week after surgery. PMID:27835633

  15. Predicting borderline personality disorder features from personality traits, identity orientation, and attachment styles in Italian nonclinical adults: issues of consistency across age ranges.

    PubMed

    Fossati, Andrea; Borroni, Serena; Feeney, Judith; Maffei, Cesare

    2012-04-01

    The aims of this study were to assess whether Borderline Personality Disorder (BPD) features could be predicted by Big Five traits, impulsivity, identity orientation, and adult attachment patterns in a sample of 1,192 adult nonclinical participants, and to evaluate the consistency of these regression models across four age groups (<30 years, 30-39 years, 40-49 years, and >50 years, respectively). In the full sample, measures of neuroticism (N), impulsivity, and anxious insecure attachment were substantial predictors of BPD features (adjusted R(2) = .38, p < .001). Attachment scales were significant predictors of BPD features across all age groups, but different scales were relevant in different age groups. Our results suggest that in nonclinical populations, BPD may represent a complex constellation of personality traits and disturbed attachment patterns.

  16. The CIRCORT database: Reference ranges and seasonal changes in diurnal salivary cortisol derived from a meta-dataset comprised of 15 field studies

    PubMed Central

    Miller, Robert; Stalder, Tobias; Jarczok, Marc; Almeida, David M.; Badrick, Ellena; Bartels, Meike; Boomsma, Dorret I.; Coe, Christopher L.; Dekker, Marieke C. J.; Donzella, Bonny; Fischer, Joachim E.; Gunnar, Megan R.; Kumari, Meena; Lederbogen, Florian; Oldehinkel, Albertine J.; Power, Christine; Rosmalen, Judith G.; Ryff, Carol D.; Subramanian, S V; Tiemeier, Henning; Watamura, Sarah E.; Kirschbaum, Clemens

    2016-01-01

    Diurnal salivary cortisol profiles are valuable indicators of adrenocortical functioning in epidemiological research and clinical practice. However, normative reference values derived from a large number of participants and across a wide age range are still missing. To fill this gap, data were compiled from 15 independently conducted field studies with a total of 104,623 salivary cortisol samples obtained from 18,698 unselected individuals (mean age: 48.3 years, age range: 0.5 to 98.5 years, 39% females). Besides providing a descriptive analysis of the complete dataset, we also performed mixed-effects growth curve modeling of diurnal salivary cortisol (i.e., 1 to 16 hours after awakening). Cortisol decreased significantly across the day and was influenced by both, age and sex. Intriguingly, we also found a pronounced impact of sampling season with elevated diurnal cortisol in spring and decreased levels in autumn. However, the majority of variance was accounted for by between-participant and between-study variance components. Based on these analyses, reference ranges (LC/MS-MS calibrated) for cortisol concentrations in saliva were derived for different times across the day, with more specific reference ranges generated for males and females in different age categories. This integrative summary provides important reference values on salivary cortisol to aid basic scientists and clinicians in interpreting deviations from the normal diurnal cycle. PMID:27448524

  17. Space radiation studies at the White Sands Missile Range Fast Burst Reactor

    NASA Technical Reports Server (NTRS)

    Delapaz, A.

    1972-01-01

    The operation of the White Sands Missile Range Fast Burst Reactor is discussed. Space radiation studies in radiobiology, dosimetry, and transient radiation effects on electronic systems and components are described. Proposed modifications to increase the capability of the facility are discussed.

  18. Pressurized-water reactor internals aging degradation study. Phase 1

    SciTech Connect

    Luk, K.H.

    1993-09-01

    This report documents the results of a Phase I study on the effects of aging degradations on pr internals. Primary stressers for internals an generated by the primary coolant flow in the they include unsteady hydrodynamic forces and pump-generated pressure pulsations. Other stressors are applied loads, manufacturing processes, impurities in the coolant and exposures to fast neutron fluxes. A survey of reported aging-related failure information indicates that fatigue, stress corrosion cracking (SCC) and mechanical wear are the three major aging-related degradation mechanisms for PWR internals. Significant reported failures include thermal shield flow-induced vibration problems, SCC in guide tube support pins and core support structure bolts, fatigue-induced core baffle water-jet impingement problems and excess wear in flux thimbles. Many of the reported problems have been resolved by accepted engineering practices. Uncertainties remain in the assessment of long-term neutron irradiation effects and environmental factors in high-cycle fatigue failures. Reactor internals are examined by visual inspections and the technique is access limited. Improved inspection methods, especially one with an early failure detection capability, can enhance the safety and efficiency of reactor operations.

  19. Boiling-Water Reactor internals aging degradation study. Phase 1

    SciTech Connect

    Luk, K.H.

    1993-09-01

    This report documents the results of an aging assessment study for boiling water reactor (BWR) internals. Major stressors for BWR internals are related to unsteady hydrodynamic forces generated by the primary coolant flow in the reactor vessel. Welding and cold-working, dissolved oxygen and impurities in the coolant, applied loads and exposures to fast neutron fluxes are other important stressors. Based on results of a component failure information survey, stress corrosion cracking (SCC) and fatigue are identified as the two major aging-related degradation mechanisms for BWR internals. Significant reported failures include SCC in jet-pump holddown beams, in-core neutron flux monitor dry tubes and core spray spargers. Fatigue failures were detected in feedwater spargers. The implementation of a plant Hydrogen Water Chemistry (HWC) program is considered as a promising method for controlling SCC problems in BWR. More operating data are needed to evaluate its effectiveness for internal components. Long-term fast neutron irradiation effects and high-cycle fatigue in a corrosive environment are uncertainty factors in the aging assessment process. BWR internals are examined by visual inspections and the method is access limited. The presence of a large water gap and an absence of ex-core neutron flux monitors may handicap the use of advanced inspection methods, such as neutron noise vibration measurements, for BWR.

  20. Aging in mouse and human systems: a comparative study.

    PubMed

    Demetrius, Lloyd

    2006-05-01

    This article discusses the significance of mouse models as a basis for elucidating the aging process in humans. We identify certain parallels between mouse and human systems and review the theoretical and empirical support for the claim that the large divergence in the rate of aging between the two species resides in differences in the stability of their metabolic networks. We will show that these differences in metabolic stability have their origin in the different ecological constraints the species experience during their evolutionary history. We exploit these ideas to compare the effect of caloric restriction on murine and human systems. The studies predict that the large increases in mean life span and maximum life-span potential observed in laboratory rodents subject to caloric restriction will not obtain in human populations. We predict that, in view of the different metabolic stability of the two systems, caloric restriction will have no effect on the maximum life-span potential of humans, and a relatively minor effect on the mean life span of nonobese populations. This article thus points to certain intrinsic limitations in the use of mouse models in elucidating the aging process in humans. We furthermore contend the view that these limitations can be mitigated by considering the metabolic stability of the two species.

  1. 2012 ACCOMPLISHMENTS - TRITIUM AGING STUDIES ON STAINLESS STEELS

    SciTech Connect

    Morgan, M.

    2013-01-31

    This report summarizes the research and development accomplishments during FY12 for the tritium effects on materials program. The tritium effects on materials program is designed to measure the long-term effects of tritium and its radioactive decay product, helium-3, on the structural properties of forged stainless steels which are used as the materials of construction for tritium reservoirs. The FY12 R&D accomplishments include: (1) Fabricated and Thermally-Charged 150 Forged Stainless Steel Samples with Tritium for Future Aging Studies; (2) Developed an Experimental Plan for Measuring Cracking Thresholds of Tritium-Charged-and-Aged Steels in High Pressure Hydrogen Gas; (3) Calculated Sample Tritium Contents For Laboratory Inventory Requirements and Environmental Release Estimates; (4) Published report on “Cracking Thresholds and Fracture Toughness Properties of Tritium-Charged-and-Aged Stainless Steels”; and, (5) Published report on “The Effects of Hydrogen, Tritium, and Heat Treatment on the Deformation and Fracture Toughness Properties of Stainless Steels”. These accomplishments are highlighted here and references given to additional reports for more detailed information.

  2. A Study of Elementary and Secondary Teacher Knowledge and Attitudes toward Aging and the Implementation of Aging Education in Taiwan

    ERIC Educational Resources Information Center

    Huang, Chin-Shan

    2012-01-01

    This study surveys elementary and secondary teachers in Taiwan and compares the findings with other studies conducted in America and Japan. The objective is to explore differences among teachers in Taiwan, Japan, and the United States in terms of their knowledge of, and attitudes toward, aging and the implementation of aging education in schools.…

  3. A systemic-wholistic view of psychological functioning in very old age: introduction to a collection of articles from the Berlin Aging Study.

    PubMed

    Baltes, P B; Smith, J

    1997-09-01

    Introduced are articles from the Berlin Aging Study (BASE) that collectively illustrate systemic-wholistic approaches to psychological functioning in old age. A systemic-wholistic perspective aims to elucidate structural and functional interdependencies between domains and to provide an integrative account of individual functioning. The special features of BASE (age range, 70-105 years; heterogeneous sample stratified by age and gender; and multidisciplinary data collection) are suited to this purpose. This article outlines the design of BASE, describes the cross-sectional sample (N = 516: 258 men and 258 women), and reports sample selectivity analyses on 25 criterion variables in which the Pearson-Lawley selection formulas were used. Although the BASE sample is positively biased, it is not restricted in heterogeneity and does not exhibit major differences in patterns of covariation among variables. This finding supports the use of BASE data for the intended systemic-wholistic analyses.

  4. Multi-ethnic reference values for spirometry for the 3-95-yr age range: the global lung function 2012 equations.

    PubMed

    Quanjer, Philip H; Stanojevic, Sanja; Cole, Tim J; Baur, Xaver; Hall, Graham L; Culver, Bruce H; Enright, Paul L; Hankinson, John L; Ip, Mary S M; Zheng, Jinping; Stocks, Janet

    2012-12-01

    The aim of the Task Force was to derive continuous prediction equations and their lower limits of normal for spirometric indices, which are applicable globally. Over 160,000 data points from 72 centres in 33 countries were shared with the European Respiratory Society Global Lung Function Initiative. Eliminating data that could not be used (mostly missing ethnic group, some outliers) left 97,759 records of healthy nonsmokers (55.3% females) aged 2.5-95 yrs. Lung function data were collated and prediction equations derived using the LMS method, which allows simultaneous modelling of the mean (mu), the coefficient of variation (sigma) and skewness (lambda) of a distribution family. After discarding 23,572 records, mostly because they could not be combined with other ethnic or geographic groups, reference equations were derived for healthy individuals aged 3-95 yrs for Caucasians (n=57,395), African-Americans (n=3,545), and North (n=4,992) and South East Asians (n=8,255). Forced expiratory value in 1 s (FEV(1)) and forced vital capacity (FVC) between ethnic groups differed proportionally from that in Caucasians, such that FEV(1)/FVC remained virtually independent of ethnic group. For individuals not represented by these four groups, or of mixed ethnic origins, a composite equation taken as the average of the above equations is provided to facilitate interpretation until a more appropriate solution is developed. Spirometric prediction equations for the 3-95-age range are now available that include appropriate age-dependent lower limits of normal. They can be applied globally to different ethnic groups. Additional data from the Indian subcontinent and Arabic, Polynesian and Latin American countries, as well as Africa will further improve these equations in the future.

  5. Interrelationship of the Risser sign, knee epiphysis, and bone age in determining skeletal maturity: a case-control study.

    PubMed

    Kim, Hak Jun; Yoon, Jung-Ro; Modi, Chetna; Modi, Hitesh; Song, Hae-Ryong; Song, Sang-Youn

    2011-05-01

    The purpose of our study was to correlate the chronological age with Risser staging, knee epiphyseal closure, and bone age by the Tanner and Whitehouse (TW3) or Greulich and Pyle (GP) method simultaneously, to find out the most correlated methods used to calculate the age in a Korean population. A case-control study was carried out in 293 children between the age of 9 and 18 years. Skeletal age was estimated by using the atlas of the GP and TW3 methods; knee epiphysis closure and the Risser staging were also noted. Spearman's correlation coefficient test showed that in both the sexes the GP method is more correlated (r=0.58 for female patients, range: 0.55-0.61; and 0.58 for male patients, range: 0.54-0.61) with the Risser staging and physeal stages of the knee joint than the TW3 method (r=0.52 for female patients, range: 0.44-0.61; and 0.55 for male patients, range: 0.48-0.61) in Korean children. Our results suggested that by using the combination of Risser sign, knee epiphyseal closure, and GP bone age, one can calculate a person's chronological age most accurately.

  6. Comparative study of limited-range wavelength conversion policies for asynchronous optical packet switching

    NASA Astrophysics Data System (ADS)

    Dogan, Kaan; Gunalay, Yavuz; Akar, Nail

    2007-02-01

    We study an asynchronous optical packet (OP)-switching node equipped with a number of limited range (LR) wavelength converters shared per output link. We study both circular and noncircular LR-wavelength-conversion schemes. A wavelength conversion policy governs the selection of the outgoing wavelength for an OP if the incoming wavelength is in use. Through simulations, we show that the so-called far-conversion policy for which the OP is switched onto the farthest available wavelength in the tuning range, outperforms the other policies we studied. We point out the clustering effect in the use of wavelengths to explain this phenomenon. We also provide an approximate analytical method to find the packet-blocking probability in circular-type LR-wavelength-conversion systems. Based on the simulation results, the approximate method appears to lead to a lower bound for blocking probabilities for all the conversion policies we study.

  7. Prediction of age and gender using digital radiographic method: A retrospective study

    PubMed Central

    Poongodi, V.; Kanmani, R.; Anandi, M. S.; Krithika, C. L.; Kannan, A.; Raghuram, P. H.

    2015-01-01

    Aim and Objective: To investigate age, sex based on gonial angle, width and breadth of the ramus of the mandible by digital orthopantomograph. Materials and Methods: A total of 200 panoramic radiographic images were selected. The age of the individuals ranged between 4 and 75 years of both the gender - males (113) and females (87) and selected radiographic images were measured using KLONK image measurement software tool with linear, angular measurement. The investigated radiographs were collected from the records of SRM Dental College, Department of Oral Medicine and Radiology. Radiographs with any pathology, facial deformities, if no observation of mental foramen, congenital deformities, magnification, and distortion were excluded. Results: Mean, median, standard deviation, derived to check the first and third quartile, linear regression is used to check age and gender correlation with angle of mandible, height and width of the ramus of mandible. Conclusion: The radiographic method is a simpler and cost-effective method of age identification compared with histological and biochemical methods. Mandible is strongest facial bone after the skull, pelvic bone. It is validatory to predict age and gender by many previous studies. Radiographic and tomographic images have become an essential aid for human identification in forensic dentistry forensic dentists can choose the most appropriate one since the validity of age and gender estimation crucially depends on the method used and its proper application. PMID:26538907

  8. Time-reversed lasing in the terahertz range and its preliminary study in sensor applications

    NASA Astrophysics Data System (ADS)

    Shen, Yun; Liu, Huaqing; Deng, Xiaohua; Wang, Guoping

    2017-02-01

    Time-reversed lasing in a uniform slab and a grating structure are investigated in the terahertz range. The results show that both the uniform slab and grating can support terahertz time-reversed lasing. Nevertheless, due to the tunable effective refractive index, the grating structure can not only exhibit time-reversed lasing more effectively and flexibly than a uniform slab, but also can realize significant absorption in a broader operating frequency range. Furthermore, applications of terahertz time-reversed lasing for novel concentration/thickness sensors are preliminarily studied in a single-channel coherent perfect absorber system.

  9. Psychotic experiences and psychotic disorders at age 18 in relation to psychotic experiences at age 12 in a longitudinal population-based cohort study.

    PubMed

    Zammit, Stanley; Kounali, Daphne; Cannon, Mary; David, Anthony S; Gunnell, David; Heron, Jon; Jones, Peter B; Lewis, Shôn; Sullivan, Sarah; Wolke, Dieter; Lewis, Glyn

    2013-07-01

    OBJECTIVE The authors examined the development of psychotic experiences and psychotic disorders in a large population-based sample of young adults and explored their relationship to psychotic phenomena earlier in childhood. METHOD The authors conducted a longitudinal birth cohort study of individuals assessed with the semistructured Psychosis-Like Symptom Interviews at ages 12 and 18 years. RESULTS Of the 4,724 individuals interviewed at age 18, 433 (9.2%) had either suspected (N=203 [4.3%]) or definite (N=230 [4.9%]) psychotic experiences. Of these, 79 (1.7%) met criteria for a psychotic disorder, and of those, only 50% sought professional help. All psychotic outcomes were more likely in young women and in those from socioeconomically disadvantaged backgrounds. Of the participants who had psychotic experiences at age 12, 78.7% had remitted by age 18. The risk of psychotic disorders at age 18 was greater in those with suspected (odds ratio=5.6, 95% CI=2.6-12.1) and especially in those with definite (odds ratio=12.7, 95% CI=6.2-26.1) psychotic experiences at age 12, and also among those with psychotic experiences at age 12 attributed to sleep or fever or with nonpsychotic experiences such as depersonalization. The positive predictive values for increasing frequency of experiences at age 12 predicting psychotic disorders at age 18 ranged from 5.5% to 22.8%. CONCLUSIONS Despite evidence for a continuum of psychotic experiences from as early as age 12, positive predictive values for predicting psychotic disorders were too low to offer real potential for targeted interventions. Psychotic disorders in young adults are relatively uncommon, but they constitute an important unmet need for care given that half of the individuals in this study who met criteria for a psychiatric disorder had not sought help for these problems despite high levels of associated distress and impairment.

  10. Computational study of the ZGB model with a long-range interaction

    NASA Astrophysics Data System (ADS)

    Chan, Chor-Hoi; Rikvold, Per Arne

    2014-03-01

    The Ziff-Gulari-Barshad (ZGB) model is widely used to study the oxidation of carbon monoxide (CO) on a catalyst surface. It exhibits a non-equilibrium, discontinuous phase transition between a reactive and a CO poisoned phase. If one allows a nonzero rate of CO desorption (k), the line of phase transitions is terminated at a critical point (kc). In this work, instead of restricting the CO and atomic oxygen (O) to react only when they are absorbed in close proximity, we consider a model that allows CO and O atoms adsorbed far apart on the lattice to react to form carbon dioxide (CO2). We employ Monte Carlo simulations to study the critical properties of this system, and we find that the non-equilibrium critical point changes from the Ising universality class to the mean-field universality class upon introducing even a very weak long-range interaction term. This behavior is consistent with that of the equilibrium Ising ferromagnet with additional weak long-range interactions. Through this study we hope to gain further understanding of the ways that a long-range interaction can affect an originally short-range interacting non-equilibrium system. Supported by NSF DMR-1104829.

  11. Questions for future studies: social relationships in old age.

    PubMed

    Troll, L E

    1999-01-01

    It is impressive, not to mention refreshing, to see four careful, weighty studies on social relationships that are not primarily concerned with caregiving. The fact that they are both longitudinal and cross-cultural makes them even more impressive and highlights general issues in the area of social relationships as well as more specific issues of aging. Four issues seem to me to be notable: 1) kinds of relationships, 2) continuity of relationships, 3) functions of relationships, and 4) cultural differences. I will consider each in turn.

  12. Dental age assessment on panoramic radiographs in a Swiss population: a validation study of two prediction models

    PubMed Central

    Kiliaridis, Stavros; Combescure, Christophe; Vazquez, Lydia

    2016-01-01

    Objectives: Dental age assessment methods are widely used for age estimation. This study aimed to analyse the accuracy of a meta-analysis method to estimate dental age in Swiss individuals and to detect potential limitations of the method. Precision of repeated tooth staging using Demirjian's classification on maxillary and mandibular teeth was also assessed. Methods: Panoramic radiographs of 50 Swiss white healthy children were analysed. Developing teeth on the left maxilla and mandible and all third permanent molars were staged following Demirjian's classification. Dental age was calculated for each subject, using a random effects model and a fixed effect model, and compared with chronological age. Results: The mean error of the dental age ranged between −3 and +1 months for both the calculation models. Dental age calculated with the fixed effect model overestimated the age of the subjects (average + 0.10 y, ranging from −1.95 y to +2.16 y) compared with their chronological age, whereas the random effects model underestimated the age (average −0.32 y, ranging from −2.24 y to +1.61 y). Conclusions: Demirjian's method allowed a precise repeated staging of maxillary and mandibular developing teeth. For both calculation models, dental age correlated well, on average, with chronological age of Swiss subjects younger than 12 years. The random effects model showed a better accuracy for these subjects than the fixed effect model. However, both models underestimated the chronological age in subjects older than 12 years. PMID:26250402

  13. Parabiosis for the study of age-related chronic disease

    PubMed Central

    Eggel, Alexander; Wyss-Coray, Tony

    2014-01-01

    Summary Modern medicine wields the power to treat large numbers of diseases and injuries most of us would have died from just a hundred years ago. In view of this tremendous achievement, it can seem as if progress has slowed, and we have been unable to impact the most devastating diseases of our time. Chronic diseases of age such as cardiovascular disease, diabetes, osteoarthritis, or Alzheimer’s disease turn out to be of a complexity that may require transformative ideas and paradigms to understand and treat them. Parabiosis, which mimics aspects of the naturally occurring shared blood supply in conjoined twins in humans and certain animals, may just have the power to be such a transformative experimental paradigm. Forgotten and now shunned in many countries, it has contributed to major breakthroughs in tumor biology, endocrinology, and transplantation research in the past century, and a set of new studies in the US and Britain report stunning advances in stem cell biology and tissue regeneration using parabiosis between young and old mice. We review here briefly the history of parabiosis and discuss its utility to study physiological and pathophysiological processes. We argue that parabiosis is a technique that should enjoy wider acceptance and application, and that policies should be revisited especially if one is to study complex age-related, chronic disorders. PMID:24496774

  14. The Basel longitudinal study on aging (1955-1978). Ophthalmo-gerontological research results.

    PubMed

    Brückner, R; Batschelet, E; Hugenschmidt, F

    1986-01-01

    In the prospective Basel longitudinal study on aging (1955-1978) 123 men (age at entry from 6-61 years) were investigated in 2 year (average) intervals. Complete case histories are available on 67 subjects over the entire period (19.6 +/- 0.85 years). Part I of the study was to confirm the hypothesis of Bernstein and of Steinhaus, according to which life expectancy can be estimated from the speed of development of presbyopia. Parallel to the measurement of accommodation range (after preliminary determination of refraction and visual acuity), the development of height, body weight, vital capacity, expiratory volume, chest circumference, abdominal circumference, blood pressure, ECG and pulse wave velocity were measured. Invasive investigations were not undertaken. Only when hypertension was combined with obesity was the diminution of accommodation range striking (Fig. 10c; however there were only 3 subjects in this risk group). Taking everything into consideration there was a concomitance between decrease of accommodation range and changes of medical parameters (Table 6). Intercurrent illness did not influence the accommodation range. Longitudinal measurements and cross-sectional comparisons (data averaged to the same point as of the same age) were carried out. The results did not always coincide. We could not confirm the hypothesis of Bernstein and of Steinhaus. In Part II the results of the objective measurements are given. Apparently growth of the skull does not stop entirely. The increase of interpupillary distance can be complete at 17 years of age, but also can continue to the 30th year. The palpebral fissure increases an average of 3 mm more horizontally between the 6th and the 20th year of life. The corneal diameter remains constant in all age classes, that is, the growth of the cornea should be complete before the 6th year of life. Early arcus senilis changes are found already in the 20-year-old. The increase in the course of time of arcus senilis is obvious

  15. Modelling ranging behaviour of female orang-utans: a case study in Tuanan, Central Kalimantan, Indonesia.

    PubMed

    Wartmann, Flurina M; Purves, Ross S; van Schaik, Carel P

    2010-04-01

    Quantification of the spatial needs of individuals and populations is vitally important for management and conservation. Geographic information systems (GIS) have recently become important analytical tools in wildlife biology, improving our ability to understand animal movement patterns, especially when very large data sets are collected. This study aims at combining the field of GIS with primatology to model and analyse space-use patterns of wild orang-utans. Home ranges of female orang-utans in the Tuanan Mawas forest reserve in Central Kalimantan, Indonesia were modelled with kernel density estimation methods. Kernel results were compared with minimum convex polygon estimates, and were found to perform better, because they were less sensitive to sample size and produced more reliable estimates. Furthermore, daily travel paths were calculated from 970 complete follow days. Annual ranges for the resident females were approximately 200 ha and remained stable over several years; total home range size was estimated to be 275 ha. On average, each female shared a third of her home range with each neighbouring female. Orang-utan females in Tuanan built their night nest on average 414 m away from the morning nest, whereas average daily travel path length was 777 m. A significant effect of fruit availability on day path length was found. Sexually active females covered longer distances per day and may also temporarily expand their ranges.

  16. Impact of the material composition on proton range variation - A Monte Carlo study

    NASA Astrophysics Data System (ADS)

    Wu, S. W.; Tung, C. J.; Lee, C. C.; Fan, K. H.; Huang, H. C.; Chao, T. C.

    2015-11-01

    In this study, we used the Geant4 toolkit to demonstrate the impacts of the material composition of tissues on proton range variation. Bragg curves of different materials subjected to a 250 MeV mono-energy proton beam were simulated and compared. These simulated materials included adipose, heart, brain, cartilage, cortical bone and water. The results showed that there was significant proton range deviation between Bragg curves, especially for cortical bone. The R50 values for a 250 MeV proton beam were approximately 39.55 cm, 35.52 cm, 37.00 cm, 36.51 cm, 36.72 cm, 22.53 cm, and 38.52 cm in the phantoms that were composed completely of adipose, cartilage, tissue, heart, brain, cortical bone, and water, respectively. Mass density and electron density were used to scale the proton range for each material; electron density provided better range scaling. In addition, a similar comparison was performed by artificially setting all material density to 1.0 g/cm3 to evaluate the range deviation due to chemical components alone. Tissue heterogeneity effects due to density variation were more significant, and less significant for chemical composition variation unless the Z/A was very different.

  17. Advanced maternal age and risk perception: A qualitative study

    PubMed Central

    2012-01-01

    Background Advanced maternal age (AMA) is associated with several adverse pregnancy outcomes, hence these pregnancies are considered to be “high risk.” A review of the empirical literature suggests that it is not clear how women of AMA evaluate their pregnancy risk. This study aimed to address this gap by exploring the risk perception of pregnant women of AMA. Methods A qualitative descriptive study was undertaken to obtain a rich and detailed source of explanatory data regarding perceived pregnancy risk of 15 women of AMA. The sample was recruited from a variety of settings in Winnipeg, Canada. In-depth interviews were conducted with nulliparous women aged 35 years or older, in their third trimester, and with singleton pregnancies. Interviews were recorded and transcribed verbatim, and content analysis was used to identify themes and categories. Results Four main themes emerged: definition of pregnancy risk, factors influencing risk perception, risk alleviation strategies, and risk communication with health professionals. Conclusions Several factors may influence women's perception of pregnancy risk including medical risk, psychological elements, characteristics of the risk, stage of pregnancy, and health care provider’s opinion. Understanding these influential factors may help health professionals who care for pregnant women of AMA to gain insight into their perspectives on pregnancy risk and improve the effectiveness of risk communication strategies with this group. PMID:22988825

  18. Style and age of late Oligocene-early Miocene deformation in the southern Stillwater Range, west central Nevada: Paleomagnetism, geochronology, and field relations

    USGS Publications Warehouse

    Hudson, Mark R.; John, David A.; Conrad, James E.; McKee, Edwin H.

    2000-01-01

    Paleomagnetic and geochronologic data combined with geologic mapping tightly restrict the timing and character of a late Oligocene to early Miocene episode of large magnitude extension in the southern Stillwater Range and adjacent regions of west central Nevada. The southern Stillwater Range was the site of an Oligocene to early Miocene volcanic center comprising (1) 28.3 to 24.3 Ma intracaldera ash flow tuffs, lava flows, and subjacent plutons associated with three calderas, (2) 24.8 to 20.7 Ma postcaldera silicic dikes and domes, and (3) unconformably overlying 15.3 to 13.0 Ma dacite to basalt lava flows, plugs, and dikes. The caldera-related tuffs, lava flows, and plutons were tilted 60°-70° either west or east during the initial period of Cenozoic deformation that accommodated over 100% extension. Directions of remanent magnetization obtained from these extrusive and intrusive, caldera-related rocks are strongly deflected from an expected Miocene direction in senses appropriate for their tilt. A mean direction for these rocks after tilt correction, however, suggests that they were also affected by a moderate (33.4° ± 11.8°) component of counterclockwise vertical axis rotation. Paleomagnetic data indicate that the episode of large tilting occurred during emplacement of 24.8 to 20.7 Ma postcaldera dikes and domes. In detail, an apparent decrease in rotation with decreasing age of individual, isotopically dated bodies of the postcaldera group indicates that most tilting occurred between 24.4 and 24.2 Ma. The onset of tilting immediately following after the final caldera eruptions suggests that the magmatism and deformation were linked. Deformation was not driven by magma buoyancy, however, because tilting equally affected the caldera systems of different ages, including their plutonic roots. It is more likely that regional extension was focused in the southern Stillwater Range due to magmatic warming and reduction of tensile strength of the brittle crust

  19. The range of replications technique for assessing the external validity of road safety evaluation studies.

    PubMed

    Elvik, Rune

    2012-03-01

    This paper introduces a simple statistical technique that can be used to assess the external validity of road safety evaluation studies. External validity refers to the possibility of generalising the results of research to other contexts than those in which it was made. There are several aspects of external validity. Two aspects that are often of interest concern the applicability of the results of road safety evaluation studies across countries and time. Can the results of studies made in one or more countries be applied in countries where studies have not been made? Can the results of studies made many years ago still be applied? The technique introduced in this paper is designed to provide support in answering these questions. The technique evaluates the stability of research results in time and space. The technique is based on cumulative meta-analysis and produces statistics that show the consistency of study results in time and space (across countries). The range of replications denotes the span of time and countries in which studies have been made. The idea is that if the results of studies are stable throughout the range of replications, one may have greater confidence in their external validity than if the results of research vary in time and between countries. The technique is illustrated by means of numerical examples.

  20. Age estimation in Indian children and adolescents in the NCR region of Haryana: A comparative study

    PubMed Central

    Gupta, Swati; Mehendiratta, Monica; Rehani, Shweta; Kumra, Madhumani; Nagpal, Ruchi; Gupta, Ramakant

    2015-01-01

    Introduction: Age estimation is a preliminary step in the identification of an individual. It is a crucial and often most critical step for forensic experts. The assessment has been standardized utilizing common dental diagnostic x-rays, but most such age-estimating systems are European population-based and their applicability has not been determined in the context of the Indian population. Aims and Objectives: To assess the applicability and to compare the methods of dental age estimation by Demirjian's method and the same method as modified by Willems (i.e. the Willems method) in Indian children of the National Capital Region (NCR). Also, to find a correlation among skeletal maturity using the Cervical vertebrae maturation index (CVMI), dental maturity, and chronological age in the same population. Materials and Methods: This cross-sectional study was conducted using dental radiographs of 70 orthodontic patients (37 males, 33 females) in the age range 9-16 years selected by simple random sampling. pantomogram were used to estimate dental age by Demirjian's method and the Willems method using their scoring tables. Lateral cephalograms were used to estimate skeletal maturity using CVMI. The latter was compared with Demirjian's stage for mandibular left second molar. Results: Overestimation of age among males by 0.856 years and 0.496 years was found by Demirjian's and the Willems methods, respectively. Among females, both the methods underestimated the age by 0.31 years and 0.45 years, respectively. Demirjian's stage G corresponded to CVMI stage 3 in males and stage 2 in females. Conclusion: In our study, the Willems method has proved to be more accurate for age estimation among Indian males, and Demirjian's method for Indian females. A statistically significant association appeared between Demirjian's stages and CVMI among both males and females. Our study recommends the derivation of a regression formula by studying a larger section of the Indian population

  1. Age, geochemical and isotopic variations in volcanic rocks from the Coastal Range of Taiwan: Implications for magma generation in the Northern Luzon Arc

    NASA Astrophysics Data System (ADS)

    Lai, Yu-Ming; Song, Sheng-Rong; Lo, Ching-Hua; Lin, Te-Hsien; Chu, Mei-Fei; Chung, Sun-Lin

    2017-02-01

    This paper reports the first systematic analysis of age and geochemical variations in volcanic rocks from the Coastal Range of Taiwan, the Northern Luzon Arc. The rocks, recovered from four main volcanoes, vary from low-K tholeiitic to medium-K calc-alkaline basalts to dacites. The rocks are typical of arc magmatic products, exhibiting enrichment in the large ion lithophile elements and depletion in the high field strength elements. Our new 40Ar/39Ar age data constrain the youngest eruption time in each of the four volcanoes, i.e., from north to south, at 7.2 Ma (Yuemei), 4.2 Ma (Chimei), 6.2 Ma (Chengkuang'ao) and 8.5 Ma (Tuluanshan), respectively. These data indicate that volcanism in the Northern Luzon Arc did not cease progressively from north to south, as previously alleged. The high and broadly uniform Nd isotope ratios [εNd = + 10.1 to + 8.8] and trace element characteristics of the rocks suggest a principal magma source from the depleted mantle wedge. Their overall geochemical variations are ascribed to magma chamber processes. The effects of magmatic differentiation and crustal contamination differ among each volcano, most likely owing to the discrepancy of residence time in individual magma chambers. Consequently, we propose a binary mixing model for the magma generation that involves arc magmas sourced from the depleted mantle wedge and up to 5% crustal contamination with a continental fragment split off from the Eurasian margin.

  2. The Effects of a Second-Grade Social Studies Curriculum Infused with Positive Aging Concepts on Children's Attitudes towards Aging

    ERIC Educational Resources Information Center

    Hembacher, Diane; Cruise, Mary J.

    2006-01-01

    As the number of elderly people in our society increases, it becomes especially important for children to develop positive attitudes towards elders and towards their own aging. The American Association for Health Education has recommended the infusion of positive aging concepts in the K-12 curriculum. This qualitative study investigated the…

  3. The New World and the New Frontier: Studying the Age of Exploration and the Space Age with Elementary Students.

    ERIC Educational Resources Information Center

    Fritzer, Penelope; Ploger, Don

    2001-01-01

    Discusses a social studies classroom unit for use with elementary students. Focuses on comparing the age of exploration and space age exploration. Provides background information on both explorations and compares the similarities and differences between the two. Includes suggestions and questions for using this interdisciplinary approach. (CMK)

  4. Mortality Trajectories at Extreme Old Ages: A Comparative Study of Different Data Sources on U.S. Old-Age Mortality.

    PubMed

    Gavrilova, Natalia S; Gavrilov, Leonid A

    The growing number of individuals living beyond age 80 underscores the need for accurate measurement of mortality at advanced ages. Our earlier published study challenged the common view that the exponential growth of mortality with age (Gompertz law) is followed by a period of deceleration, with slower rates of mortality increase (Gavrilov and Gavrilova 2011). This refutation of mortality deceleration was made using records from the U.S. Social Security Administration's Death Master File (DMF). Taking into account the significance of this finding for actuarial theory and practice, we tested these earlier observations using additional independent datasets and alternative statistical approaches. In particular, the following data sources for U.S. mortality at advanced ages were analyzed: (1) data from the Human Mortality Database (HMD) on age-specific death rates for 1890-99 U.S. birth cohorts, (2) recent extinct birth cohorts of U.S. men and women based on DMF data, and (3) mortality data for railroad retirees. In the case of HMD data, the analyses were conducted for 1890-99 birth cohorts in the age range 80-106. Mortality was fitted by the Gompertz and logistic (Kannisto) models using weighted nonlinear regression and Akaike information criterion as the goodness-of-fit measure. All analyses were conducted separately for men and women. It was found that for all studied HMD birth cohorts, the Gompertz model demonstrated better fit of mortality data than the Kannisto model in the studied age interval. Similar results were obtained for U.S. men and women born in 1890-99 and railroad retirees born in 1895-99 using the full DMF file (obtained from the National Technical Information Service, or NTIS). It was also found that mortality estimates obtained from the DMF records are close to estimates obtained using the HMD cohort data. An alternative approach for studying mortality patterns at advanced ages is based on calculating the age-specific rate of mortality change

  5. Mortality Trajectories at Extreme Old Ages: A Comparative Study of Different Data Sources on U.S. Old-Age Mortality

    PubMed Central

    Gavrilova, Natalia S.; Gavrilov, Leonid A.

    2014-01-01

    The growing number of individuals living beyond age 80 underscores the need for accurate measurement of mortality at advanced ages. Our earlier published study challenged the common view that the exponential growth of mortality with age (Gompertz law) is followed by a period of deceleration, with slower rates of mortality increase (Gavrilov and Gavrilova 2011). This refutation of mortality deceleration was made using records from the U.S. Social Security Administration’s Death Master File (DMF). Taking into account the significance of this finding for actuarial theory and practice, we tested these earlier observations using additional independent datasets and alternative statistical approaches. In particular, the following data sources for U.S. mortality at advanced ages were analyzed: (1) data from the Human Mortality Database (HMD) on age-specific death rates for 1890–99 U.S. birth cohorts, (2) recent extinct birth cohorts of U.S. men and women based on DMF data, and (3) mortality data for railroad retirees. In the case of HMD data, the analyses were conducted for 1890–99 birth cohorts in the age range 80–106. Mortality was fitted by the Gompertz and logistic (Kannisto) models using weighted nonlinear regression and Akaike information criterion as the goodness-of-fit measure. All analyses were conducted separately for men and women. It was found that for all studied HMD birth cohorts, the Gompertz model demonstrated better fit of mortality data than the Kannisto model in the studied age interval. Similar results were obtained for U.S. men and women born in 1890–99 and railroad retirees born in 1895–99 using the full DMF file (obtained from the National Technical Information Service, or NTIS). It was also found that mortality estimates obtained from the DMF records are close to estimates obtained using the HMD cohort data. An alternative approach for studying mortality patterns at advanced ages is based on calculating the age-specific rate of mortality

  6. Association between age and knee structural change: a cross sectional MRI based study

    PubMed Central

    Ding, C; Cicuttini, F; Scott, F; Cooley, H; Jones, G

    2005-01-01

    Objective: To describe the associations between age, knee cartilage morphology, and bone size in adults. Methods: A cross sectional convenience sample of 372 male and female subjects (mean age 45 years, range 26–61) was studied. Knee measures included a cartilage defect five site score (0–4 respectively) and prevalence (defect score of ⩾2 at any site), cartilage volume and thickness, and bone surface area and/or volume. These were determined at the patellar, medial, and lateral tibial and femoral sites using T1 weighted fat saturation MRI. Height, weight, and radiographic osteoarthritis (ROA) were measured by standard protocols. Results: In multivariate analysis, age was significantly associated with knee cartilage defect scores (ß = +0.016 to +0.073/year, all p<0.01) and prevalence (OR = 1.05–1.10/year, all p<0.05) in all compartments. Additionally, age was negatively associated with knee cartilage thickness at all sites (ß = –0.013 to –0.035 mm/year, all p<0.05), and with patellar (ß = –11.5 µl/year, p<0.01) but not tibial cartilage volume. Lastly, age was significantly positively associated with medial and lateral tibial surface bone area (ß = +3.0 to +4.7 mm2/year, all p<0.05) and patellar bone volume (ß = +34.4 µl/year, p<0.05). Associations between age and tibiofemoral cartilage defect score, cartilage thickness, and bone size decreased in magnitude after adjustment for ROA, suggesting these changes are directly relevant to OA. Conclusion: The most consistent knee structural changes with increasing age are increase in cartilage defect severity and prevalence, cartilage thinning, and increase in bone size with inconsistent change in cartilage volume. Longitudinal studies are needed to determine which of these changes are primary and confirm their relevance to knee OA. PMID:15769915

  7. Aging gracefully: a comparative study of Japanese and Malaysian women aged 65-75.

    PubMed

    Kok, Jin Kuan; Yap, Yuet Ngor

    2014-12-01

    Longer lives and extended retirement have created a 'young old age' stage of life. How people spend their "young old age" has become increasingly important. This research aims to investigate the different ageing experiences of Japanese and Malaysian women and the activities they engaged in their "young old age". In-depth interviews were conducted to collect data and an adapted grounded theory approach was used for data analysis. Findings reveal many common characteristics for both groups of research participants. The emerging themes show that Japanese and Malaysian Chinese have different life missions evident in their daily activities, one passing on culture and the other passing on family values and life experience. They also differ in their choice of living arrangement (independent versus dependent/interdependent), attitudes to life (fighting versus accepting) and activities in which to engage (aesthetic pursuits versus family oriented activities).

  8. Studies of a Proton Bunch Phase Monitor for Range Verification in Proton Therapy

    SciTech Connect

    Werner, T.; Golnik, C.; Enghardt, W.; Petzoldt, J.; Kormoll, T.; Pausch, G.; Straessner, A.; Roemer, K.; Dreyer, A.; Hueso-Gonzalez, F.; Enghardt, W.

    2015-07-01

    A primary subject of the present research in particle therapy is to ensure the precise irradiation of the target volume. The prompt gamma timing (PGT) method provides one possibility for in vivo range verification during the irradiation of patients. Prompt gamma rays with high energies are emitted promptly due to nuclear reactions of protons with tissue. The arrival time of these gammas to the detector reflects the stopping process of the primary protons in tissue and is directly correlated to the range. Due to the time resolution of the detector and the proton bunch time spread, as well as drifts of the bunch phase with respect to the accelerator frequency, timing spectra are smeared out and compromise the accuracy of range information intended for future clinical applications. Nevertheless, counteracting this limitation and recovering range information from the PGT measured spectra, corrections using a bunch phase monitor can be performed. A first prototype of bunch phase monitor was tested at GSI Darmstadt, where measurements of the energy correlation profile of the ion bunches were performed. At the ELBE accelerator at Helmholtz-Zentrum Dresden-Rossendorf (HZDR), set up to provide bremsstrahlung photons in very short pulses, a constant fraction algorithm for the incoming digital signals was evaluated, which is used for optimizing the time resolution. Studies of scattering experiments with different thin targets and detector positions are accomplished at Onco Ray Dresden, where a clinical proton beam is available. These experiments allow a basic characterization of the proton bunch structure and the detection yield. (authors)

  9. Studies of a proton phase beam monitor for range verification in proton therapy

    SciTech Connect

    Werner, T.; Golnik, C.; Enghardt, W.; Petzoldt, J.; Kormoll, T.; Pausch, G.; Straessner, A.; Roemer, K.; Dreyer, A.; Hueso-Gonzalez, F.; Enghardt, W.

    2015-07-01

    A primary subject of the present research in particle therapy is to ensure the precise irradiation of the target volume. The prompt gamma timing (PGT) method provides one possibility for in vivo range verification during the irradiation of patients. Prompt gamma rays with high energies are emitted promptly due to nuclear reactions of protons with tissue. The arrival time of these gammas to the detector reflects the stopping process of the primary protons in tissue and are directly correlated to the range. Due to the time resolution of the detector and the proton bunch time spread, as well as drifts of the bunch phase with respect to the accelerator frequency, timing spectra are smeared out and compromise the accuracy of range information intended for future clinical applications. Nevertheless, counteracting this limitation and recovering range information from the PGT measured spectra, corrections using a phase beam monitor can be performed. A first prototype of phase beam monitor was tested at GSI Darmstadt, where measurements of the energy profile of the ion bunches were performed. At the ELBE accelerator Helmholtz-Zentrum Dresden-Rossendorf (HZDR), set up to provide bremsstrahlung photons in very short pulses, a constant fraction algorithm for the incoming digital signals was evaluated, which is used for optimizing the time resolution. Studies of scattering experiments with different thin targets and detector positions are accomplished at Oncoray Dresden, where a clinical proton beam is available. These experiments allow a basic characterization of the proton bunch structure and the detection yield. (authors)

  10. Experimental Approaches to the Study of Epigenomic Dysregulation in Ageing

    PubMed Central

    Thompson, Reid F.; Fazzari, Melissa J.; Greally, John M.

    2010-01-01

    In this review, we describe how normal ageing may involve the acquisition of epigenetic errors over time, akin to the accumulation of genetic mutations with ageing. We describe how such experiments are currently performed, their limitations technically and analytically and their application to ageing research. PMID:20060885

  11. Critical study of Jara (aging) and its management.

    PubMed

    Parmar, Nisha; Vyas, Mahesh; Vyas, Hitesh

    2012-04-01

    Jara Avastha (stage of old age) is the later phase of life in which maximum decline of bodily elements is observed. Paramanuvibhaga (cell division) takes place at every moment; particularly in old age, it will be fast in comparison with other phases of life. Some organ related changes also take place during this period, which are the decades of Balya, Vridhhi, Chhavi, Medha, Twak, etc., In this study, applied aspects of Medha Hani, Twak Hani, and Drishti Hani were evaluated subjectively as well as objectively. Patients were selected from the OPD of Department of Basic Principles, I.P.G.T. and R.A., Gujarat Ayurved University, Jamnagar, irrespective of their sex, caste, religion, etc., and randomly divided into two groups. Patients in Group A were treated with Panchagavya Ghrita and Group B with plain Go Ghrita for 90 days and the dose of drug was 10 g/day at Nirannakala (early morning with empty stomach). Both groups showed significant results, the difference in between the groups is statistically insignificant.

  12. Critical study of Jara (aging) and its management

    PubMed Central

    Parmar, Nisha; Vyas, Mahesh; Vyas, Hitesh

    2012-01-01

    Jara Avastha (stage of old age) is the later phase of life in which maximum decline of bodily elements is observed. Paramanuvibhaga (cell division) takes place at every moment; particularly in old age, it will be fast in comparison with other phases of life. Some organ related changes also take place during this period, which are the decades of Balya, Vridhhi, Chhavi, Medha, Twak, etc., In this study, applied aspects of Medha Hani, Twak Hani, and Drishti Hani were evaluated subjectively as well as objectively. Patients were selected from the OPD of Department of Basic Principles, I.P.G.T. and R.A., Gujarat Ayurved University, Jamnagar, irrespective of their sex, caste, religion, etc., and randomly divided into two groups. Patients in Group A were treated with Panchagavya Ghrita and Group B with plain Go Ghrita for 90 days and the dose of drug was 10 g/day at Nirannakala (early morning with empty stomach). Both groups showed significant results, the difference in between the groups is statistically insignificant. PMID:23559801

  13. Laboratory study of sonic booms and their scaling laws. [ballistic range simulation

    NASA Technical Reports Server (NTRS)

    Toong, T. Y.

    1974-01-01

    This program undertook to seek a basic understanding of non-linear effects associated with caustics, through laboratory simulation experiments of sonic booms in a ballistic range and a coordinated theoretical study of scaling laws. Two cases of superbooms or enhanced sonic booms at caustics have been studied. The first case, referred to as acceleration superbooms, is related to the enhanced sonic booms generated during the acceleration maneuvers of supersonic aircrafts. The second case, referred to as refraction superbooms, involves the superbooms that are generated as a result of atmospheric refraction. Important theoretical and experimental results are briefly reported.

  14. 32-channel pyrometer with high dynamic range for studies of shocked nanothermites

    NASA Astrophysics Data System (ADS)

    Bassett, Will P.; Dlott, Dana D.

    2017-01-01

    A 32-channel optical pyrometer has been developed for studying temperature dynamics of shock-initiated reactive materials with one nanosecond time resolution and high dynamic range. The pyrometer consists of a prism spectrograph which directs the spectrally-resolved emission to 32 fiber optics and 32 photomultiplier tubes and digitizers. Preliminary results show shock-initiated reactions of a nanothermite composite, nano CuO/Al in nitrocellulose binder, consists of three stages. The first stage occurred at 30 ns, right after the shock unloaded, the second stage at 100 ns and the third at 1 μs, and the temperatures ranged from 2100K to 3000K. Time-resolved emission spectra suggest hot spots formed during shock unloading, which initiated the bulk thermite/nitrocellulose reaction.

  15. Comparison of Stopping Power and Range Databases for Radiation Transport Study

    NASA Technical Reports Server (NTRS)

    Tai, H.; Bichsel, Hans; Wilson, John W.; Shinn, Judy L.; Cucinotta, Francis A.; Badavi, Francis F.

    1997-01-01

    The codes used to calculate stopping power and range for the space radiation shielding program at the Langley Research Center are based on the work of Ziegler but with modifications. As more experience is gained from experiments at heavy ion accelerators, prudence dictates a reevaluation of the current databases. Numerical values of stopping power and range calculated from four different codes currently in use are presented for selected ions and materials in the energy domain suitable for space radiation transport. This study of radiation transport has found that for most collision systems and for intermediate particle energies, agreement is less than 1 percent, in general, among all the codes. However, greater discrepancies are seen for heavy systems, especially at low particle energies.

  16. Longitudinal studies of the immune response of Colombian patients infected with Trypanosoma cruzi and T. rangeli.

    PubMed

    Hudson, L; Guhl, F; de Sanchez, N; Bridge, D; Jaramillo, C A; Young, A

    1988-06-01

    Two groups of patients were examined for anti-Trypanosoma cruzi antibodies by immunofluorescence and ELISA (i) inhabitants of the village and surrounding rural area of Tibu, Norte de Santander, Columbia (n = 327) and (ii) employees of the Empresa Colombiana de Petroleos (ECOPETROL, n = 849). The latter group had a lower rate of positive serology (12 as compared to 29%) but the distributions of antibody titres were very similar in the two groups. A total of 119 serum samples (37 village and 82 ECOPETROL, including 25 seronegative controls) were analysed for their ability to immunoprecipitate the 7 major polypeptides of T. cruzi trypomastigotes of Mr greater than 72 kDa. Although 10 sera from positive patients showed no immunoprecipitation, all of the remaining positive sera contained antibodies which reacted with the 150, 90 and 85 kDa polypeptides. When the T. cruzi immunofluorescence positive, immunoprecipitation negative sera were retested by ELISA using GP90, all were negative thus suggesting that the patients had had a misdiagnosed T. rangeli infection. The new diagnosis was confirmed by immunofluorescence and ELISA with T. rangeli epimastigotes. Longitudinal studies were carried out on 19 patients from the ECOPETROL group for up to 3.5 years. Five seropositive patients showed a change in their anti-trypomastigote immunoprecipitation profiles over this period; one by loss of a previously recognized high molecular weight band and four others by conversion from a negative to a positive immunoprecipitation profile. These latter patients presented initially with uncomplicated T. rangeli infection but then acquired a T. cruzi superinfection. These patients represent the nucleus of a group in which prospective studies will identify the effect of T. rangeli infection on the course of subsequent South American trypanosomiasis and Chagas' disease.

  17. Long-term ambient particle exposures and blood DNA methylation age: findings from the VA normative aging study

    PubMed Central

    Nwanaji-Enwerem, Jamaji C.; Colicino, Elena; Trevisi, Letizia; Kloog, Itai; Just, Allan C.; Shen, Jincheng; Brennan, Kasey; Dereix, Alexandra; Hou, Lifang; Vokonas, Pantel; Schwartz, Joel; Baccarelli, Andrea A.

    2016-01-01

    Background Ambient particles have been shown to exacerbate measures of biological aging; yet, no studies have examined their relationships with DNA methylation age (DNAm-age), an epigenome-wide DNA methylation based predictor of chronological age. Objective We examined the relationship of DNAm-age with fine particulate matter (PM2.5), a measure of total inhalable particle mass, and black carbon (BC), a measure of particles from vehicular traffic. Methods We used validated spatiotemporal models to generate 1-year PM2.5 and BC exposure levels at the addresses of 589 older men participating in the VA Normative Aging Study with 1–3 visits between 2000 and 2011 (n = 1032 observations). Blood DNAm-age was calculated using 353 CpG sites from the Illumina HumanMethylation450 BeadChip. We estimated associations of PM2.5 and BC with DNAm-age using linear mixed effects models adjusted for age, lifestyle/environmental factors, and aging-related diseases. Results After adjusting for covariates, a 1-µg/m3 increase in PM2.5 (95% CI: 0.30, 0.75, P<0.0001) was significantly associated with a 0.52-year increase in DNAm-age. Adjusted BC models showed similar patterns of association (β = 3.02, 95% CI: 0.48, 5.57, P = 0.02). Only PM2.5 (β = 0.54, 95% CI: 0.24, 0.84, P = 0.0004) remained significantly associated with DNAm-age in two-particle models. Methylation levels from 20 of the 353 CpGs contributing to DNAm-age were significantly associated with PM2.5 levels in our two-particle models. Several of these CpGs mapped to genes implicated in lung pathologies including LZTFL1, PDLIM5, and ATPAF1. Conclusion Our results support an association of long-termambient particle levels with DNAm-age and suggest that DNAm-age is a biomarker of particle-related physiological processes. PMID:27453791

  18. Myocardial strain in healthy adults across a broad age range as revealed by cardiac magnetic resonance imaging at 1.5 and 3.0T: Associations of myocardial strain with myocardial region, age, and sex

    PubMed Central

    Mangion, Kenneth; Clerfond, Guillaume; McComb, Christie; Carrick, David; Rauhalammi, Samuli M.; McClure, John; Corcoran, David S.; Woodward, Rosemary; Orchard, Vanessa; Radjenovic, Aleksandra; Zhong, Xiaodong

    2016-01-01

    Purpose To assess myocardial strain using cine displacement encoding with stimulated echoes (DENSE) using 1.5T and 3.0T MRI in healthy adults. Materials and Methods Healthy adults without any history of cardiovascular disease underwent magnetic resonance imaging (MRI) at 1.5T and 3.0T within 2 days. The MRI protocol included balanced steady‐state free‐precession (b‐SSFP), 2D cine‐echo planar imaging (EPI)‐DENSE, and late gadolinium enhancement in subjects >45 years. Acquisitions were divided into six segments; global and segmental peak longitudinal and circumferential strain were derived and analyzed by field strength, age, and gender. Results In all, 89 volunteers (mean age 44.8 ± 18.0 years, range: 18–87 years) underwent MRI at 1.5T, and 88 of these subjects underwent MRI at 3.0T (1.4 ± 1.4 days between the scans). Compared with 3.0T, the magnitudes of global circumferential (–19.5 ± 2.6% vs. –18.47 ± 2.6%; P = 0.001) and longitudinal (–12.47 ± 3.2% vs. –10.53 ± 3.1%; P = 0.004) strain were greater at 1.5T. At 1.5T, longitudinal strain was greater in females than in males: –10.17 ± 3.4% vs. –13.67 ± 2.4%; P = 0.001. Similar observations occurred for circumferential strain at 1.5T (–18.72 ± 2.2% vs. –20.10 ± 2.7%; P = 0.014) and at 3.0T (–17.92 ± 1.8% vs. –19.1 ± 3.1%; P = 0.047). At 1.5T, longitudinal and circumferential strain were not associated with age after accounting for sex (longitudinal strain P = 0.178, circumferential strain P = 0.733). At 3.0T, longitudinal and circumferential strain were associated with age (P < 0.05). Longitudinal strain values were greater in the apico‐septal, basal‐lateral, and mid‐lateral segments and circumferential strain in the inferior, infero‐lateral, and antero‐lateral LV segments. Conclusion Myocardial strain parameters as revealed by cine‐DENSE at different MRI field strengths were associated with myocardial region, age, and sex. J. Magn. Reson. Imaging 2016;44:1197

  19. Comparison of methods for imputing limited-range variables: a simulation study

    PubMed Central

    2014-01-01

    Background Multiple imputation (MI) was developed as a method to enable valid inferences to be obtained in the presence of missing data rather than to re-create the missing values. Within the applied setting, it remains unclear how important it is that imputed values should be plausible for individual observations. One variable type for which MI may lead to implausible values is a limited-range variable, where imputed values may fall outside the observable range. The aim of this work was to compare methods for imputing limited-range variables, with a focus on those that restrict the range of the imputed values. Methods Using data from a study of adolescent health, we consider three variables based on responses to the General Health Questionnaire (GHQ), a tool for detecting minor psychiatric illness. These variables, based on different scoring methods for the GHQ, resulted in three continuous distributions with mild, moderate and severe positive skewness. In an otherwise complete dataset, we set 33% of the GHQ observations to missing completely at random or missing at random; repeating this process to create 1000 datasets with incomplete data for each scenario. For each dataset, we imputed values on the raw scale and following a zero-skewness log transformation using: univariate regression with no rounding; post-imputation rounding; truncated normal regression; and predictive mean matching. We estimated the marginal mean of the GHQ and the association between the GHQ and a fully observed binary outcome, comparing the results with complete data statistics. Results Imputation with no rounding performed well when applied to data on the raw scale. Post-imputation rounding and imputation using truncated normal regression produced higher marginal means than the complete data estimate when data had a moderate or severe skew, and this was associated with under-coverage of the complete data estimate. Predictive mean matching also produced under-coverage of the complete data

  20. Rapidly rotating boson molecules with long- or short-range repulsion: An exact diagonalization study

    SciTech Connect

    Baksmaty, Leslie O.; Yannouleas, Constantine; Landman, Uzi

    2007-02-15

    The Hamiltonian for a small number N{<=}11 of bosons in a rapidly rotating harmonic trap, interacting via a short range (contact potential) or a long range (Coulomb) interaction, is studied via an exact diagonalization in the lowest Landau level. Our analysis shows that, for both low and high fractional fillings, the bosons localize and form rotating boson molecules (RBMs) consisting of concentric polygonal rings. Focusing on systems with the number of trapped atoms sufficiently large to form multiring bosonic molecules, we find that, as a function of the rotational frequency and regardless of the type of repulsive interaction, the ground-state angular momenta grow in specific steps that coincide with the number of localized bosons on each concentric ring. Comparison of the conditional probability distributions (CPDs) for both interactions suggests that the degree of crystalline correlations appears to depend more on the fractional filling {nu} than on the range of the interaction. The RBMs behave as nonrigid rotors, i.e., the concentric rings rotate independently of each other. At filling fractions {nu}<1/2, we observe well developed crystallinity in the CPDs (two-point correlation functions). For larger filling fractions {nu}>1/2, observation of similar molecular patterns requires consideration of even higher-order correlation functions.

  1. Feasibility study of proton-based quality assurance of proton range compensator

    NASA Astrophysics Data System (ADS)

    Park, S.; Jeong, C.; Min, B. J.; Kwak, J.; Lee, J.; Cho, S.; Shin, D.; Lim, Y. K.; Park, S. Y.; Lee, S. B.

    2013-06-01

    All patient specific range compensators (RCs) are customized for achieving distal dose conformity of target volume in passively scattered proton therapy. Compensators are milled precisely using a computerized machine. In proton therapy, precision of the compensator is critical and quality assurance (QA) is required to protect normal tissues and organs from radiation damage. This study aims to evaluate the precision of proton-based quality assurance of range compensator. First, the geometry information of two compensators was extracted from the DICOM Radiotherapy (RT) plan. Next, RCs were irradiated on the EBT film individually by proton beam which is modulated to have a photon-like percent depth dose (PDD). Step phantoms were also irradiated on the EBT film to generate calibration curve which indicates relationship between optical density of irradiated film and perpendicular depth of compensator. Comparisons were made using the mean absolute difference (MAD) between coordinate information from DICOM RT and converted depth information from the EBT film. MAD over the whole region was 1.7, and 2.0 mm. However, MAD over the relatively flat regions on each compensator selected for comparison was within 1 mm. These results shows that proton-based quality assurance of range compensator is feasible and it is expected to achieve MAD over the whole region less than 1 mm with further correction about scattering effect of proton imaging.

  2. Education does not slow cognitive decline with aging: 12-year evidence from the victoria longitudinal study.

    PubMed

    Zahodne, Laura B; Glymour, M Maria; Sparks, Catharine; Bontempo, Daniel; Dixon, Roger A; MacDonald, Stuart W S; Manly, Jennifer J

    2011-11-01

    Although the relationship between education and cognitive status is well-known, evidence regarding whether education moderates the trajectory of cognitive change in late life is conflicting. Early studies suggested that higher levels of education attenuate cognitive decline. More recent studies using improved longitudinal methods have not found that education moderates decline. Fewer studies have explored whether education exerts different effects on longitudinal changes within different cognitive domains. In the present study, we analyzed data from 1014 participants in the Victoria Longitudinal Study to examine the effects of education on composite scores reflecting verbal processing speed, working memory, verbal fluency, and verbal episodic memory. Using linear growth models adjusted for age at enrollment (range, 54-95 years) and gender, we found that years of education (range, 6-20 years) was strongly related to cognitive level in all domains, particularly verbal fluency. However, education was not related to rates of change over time for any cognitive domain. Results were similar in individuals older or younger than 70 at baseline, and when education was dichotomized to reflect high or low attainment. In this large longitudinal cohort, education was related to cognitive performance but unrelated to cognitive decline, supporting the hypothesis of passive cognitive reserve with aging.

  3. A Detailed Study of Debris Flow Source Areas in the Northern Colorado Front Range.

    NASA Astrophysics Data System (ADS)

    Arana-Morales, A.; Baum, R. L.; Godt, J.

    2014-12-01

    Nearly continuous, heavy rainfall occurred during 9-13 September 2013 causing flooding and widespread landslides and debris flows in the northern Colorado Front Range. Whereas many recent studies have identified erosion as the most common process leading to debris flows in the mountains of Colorado, nearly all of the debris flows mapped in this event began as small, shallow landslides. We mapped the boundaries of 415 September 2013 debris flows in the Eldorado Springs and Boulder 7.5-minute quadrangles using 0.5-m-resolution satellite imagery. We characterized the landslide source areas of six debris flows in the field as part of an effort to identify what factors controlled their locations. Four were on a dip slope in sedimentary rocks in the Pinebrook Hills area, near Boulder, and the other two were in granitic rocks near Gross Reservoir. Although we observed no obvious geomorphic differences between the source areas and surrounding non-landslide areas, we noted several characteristics that the source areas all had in common. Slopes of the source areas ranged from 28° to 35° and most occurred on planar or slightly concave slopes that were vegetated with grass, small shrubs, and sparse trees. The source areas were shallow, irregularly shaped, and elongated downslope: widths ranged from 4 to 9 m, lengths from 6 to 40 m and depths ranged from 0.7 to 1.2 m. Colluvium was the source material for all of the debris flows and bedrock was exposed in the basal surface of all of the source areas. We observed no evidence for concentrated surface runoff upslope from the sources. Local curvature and roughness of bedrock and surface topography, and depth distribution and heterogeneity of the colluvium appear to have controlled the specific locations of these shallow debris-flow source areas. The observed distribution and characteristics of the source areas help guide ongoing efforts to model initiation of the debris flows.

  4. A Multilaboratory, Multicountry Study To Determine Bedaquiline MIC Quality Control Ranges for Phenotypic Drug Susceptibility Testing.

    PubMed

    Kaniga, Koné; Cirillo, Daniela M; Hoffner, Sven; Ismail, Nazir A; Kaur, Devinder; Lounis, Nacer; Metchock, Beverly; Pfyffer, Gaby E; Venter, Amour

    2016-12-01

    The aim of this study was to establish standardized drug susceptibility testing (DST) methodologies and reference MIC quality control (QC) ranges for bedaquiline, a diarylquinoline antimycobacterial, used in the treatment of adults with multidrug-resistant tuberculosis. Two tier-2 QC reproducibility studies of bedaquiline DST were conducted in eight laboratories using Clinical Laboratory and Standards Institute (CLSI) guidelines. Agar dilution and broth microdilution methods were evaluated. Mycobacterium tuberculosis H37Rv was used as the QC reference strain. Bedaquiline MIC frequency, mode, and geometric mean were calculated. When resulting data occurred outside predefined CLSI criteria, the entire laboratory data set was excluded. For the agar dilution MIC, a 4-dilution QC range (0.015 to 0.12 μg/ml) centered around the geometric mean included 95.8% (7H10 agar dilution; 204/213 observations with one data set excluded) or 95.9% (7H11 agar dilution; 232/242) of bedaquiline MICs. For the 7H9 broth microdilution MIC, a 3-dilution QC range (0.015 to 0.06 μg/ml) centered around the mode included 98.1% (207/211, with one data set excluded) of bedaquiline MICs. Microbiological equivalence was demonstrated for bedaquiline MICs determined using 7H10 agar and 7H11 agar but not for bedaquiline MICs determined using 7H9 broth and 7H10 agar or 7H9 broth and 7H11 agar. Bedaquiline DST methodologies and MIC QC ranges against the H37Rv M. tuberculosis reference strain have been established: 0.015 to 0.12 μg/ml for the 7H10 and 7H11 agar dilution MICs and 0.015 to 0.06 μg/ml for the 7H9 broth microdilution MIC. These methodologies and QC ranges will be submitted to CLSI and EUCAST to inform future research and provide guidance for routine clinical bedaquiline DST in laboratories worldwide.

  5. Comparative study of three types of civil defense high-range pocket dosimeters

    SciTech Connect

    Siskel, R.L.; Sims, C.S.; Swaja, R.

    1987-01-01

    Civil defense shelters are stocked with high-range (0- to 200-R) CDV-742 pocket dosimeters. These dosimeters are intended for use by people that must leave the shelter when the environmental radiation level is either high or unknown. A total of 67 CDV-742 dosimeters were obtained and studied during the summer of 1986 at Oak Ridge National Lab. Health Physics Research Reactor (HPRR). Three different types of dosimeters (27 Bendix, 20 Landsverk-Gold, and 20 Landsverk-Yellow) in various combinations were exposed to 14 separate pulse operations of the HPRR. It can be concluded that the CDV-742 type dosimeters were not suitable for use in a neutron or mixed radiation field unless the spectra is known and correction factors determined in this study are properly applied. Further study is needed to determine the accuracy of these dosimeters in a pure gamma field and to determine their precision at the extreme ends of the dosimeter range. Furthermore, because of their failure rates, shelter occupants should consider exposure data from the Bendix and Landsverk-Yellow dosimeters to be highly unreliable unless sufficient evidence exists to support the exposure readings.

  6. Study of Saturn Electrostatic Discharges in a Wide Range of Timec SCALES

    NASA Astrophysics Data System (ADS)

    Mylostna, K.; Zakharenko, V.; Konovalenko, A.; Kolyadin, V.; Zarka, P.; Griemeier, J.-M.; Litvinenko, G.; Sidorchuk, M.; Rucker, H.; Fischer, G.; Cecconi, B.; Coffre, A.; Denis, L.; Nikolaenko, V.; Shevchenko, V.

    Saturn Electrostatic discharges (SED) are sporadic broadband impulsive radio bursts associated with lightning in Saturnian atmosphere. After 25 years of space investigations in 2006 the first successful observations of SED on the UTR-2 radio telescope were carried out [1]. Since 2007 a long-term program of ED search and study in the Solar system has started. As a part of this program the unique observations with high time resolution were taken in 2010. New possibilities of UTR-2 radio telescope allowed to provide a long-period observations and study with high temporal resolution. This article presents the results of SED study in a wide range of time scales: from seconds to microseconds. For the first time there were obtained a low frequency spectrum of SED. We calculated flux densities of individual bursts at the maximum achievable time resolution. Flux densities of most intensive bursts reach 4200 Jy.

  7. Tool for Studying the Effects of Range Restriction in Correlation Coefficient Estimation

    DTIC Science & Technology

    1990-07-01

    AFHRL-TP-90-6 AIR FORCE TOOL FOR STUDYING THE EFFECTS OF RANGE RESTRICTION IN CORRELATION COEFFICIENT ESTIMATION H U Douglas E. JacksonM Eastern New...the Lftects of kange Restriction in Correlation Coefficient Estimation PE - 62703F PR - 7719 4. AUTHOR(S) TA - 18 Douglas E. Jackson WU - 46 Malcolm J...that one must try to estimate the correlation coefficient between two random variables X and Y in some population P using data taken f-om a

  8. Study of the application of hydrogen fuel to long-range subsonic transport aircraft, volume 2

    NASA Technical Reports Server (NTRS)

    Brewer, G. D.; Morris, R. E.; Lange, R. H.; Moore, J. W.

    1975-01-01

    The feasibility, practicability, and potential advantages/disadvantages of using liquid hydrogen as fuel in long range, subsonic transport aircraft of advanced design were studied. Both passenger and cargo-type aircraft were investigated. To provide a valid basis for comparison, conventional hydrocarbon (Jet A) fueled aircraft were designed to perform identical missions using the same advanced technology and meeting the same operational constraints. The liquid hydrogen and Jet A fueled aircraft were compared on the basis of weight, size, energy utilization, cost, noise, emissions, safety, and operational characteristics. A program of technology development was formulated.

  9. Study of an efficient long-range Mach 2.7 supersonic transport configuration concept

    NASA Technical Reports Server (NTRS)

    Gall, P. D.

    1985-01-01

    A long range Mach 2.7 supersonic transport configuration concept was studied utilizing linear theory methods. The configuration was sized to carry 290 passengers 6,000 nautical miles nonstop. The final configuration has a maximum takeoff gross weight of 687,200 pounds, a wing loading of 69.8 lbf/sq.ft. and a thrust weight ratio of .278. The most significant result is that a significantly improved trimmed maximum lift drag ratio of 11.04 can be obtained for a supersonic transport at Mach 2.62 and 55,000 feet.

  10. Long-range correlations in vehicular traffic flow studied in the framework of Kerner's three-phase theory based on rescaled range analysis

    NASA Astrophysics Data System (ADS)

    Xue, Yu; Jia, Li-Si; Teng, Wei-Zhong; Lu, Wei-Zhen

    2015-05-01

    In this paper, a study on the characteristics of synchronized traffic flow in a two-lane case with partial reduced lane based on the Kerner-Klenov-Wolf (KKW) cellular automaton model in the framework of Kerner' three-phase theory is reported by using the rescaled range analysis. The local fundamental diagram and the cross correlation near the entry of the reduced lane have been analyzed. The typical two-dimensional scatter diagram in the local fundamental diagram and the non-correlation of the cross correlation between the local density and the flow reveal the characteristics of synchronized traffic flow near the entry of the reduced lane. By using the rescaled range analysis (R/S) method to calculate the Hurst exponent, we can obtain the long-range correlated characteristics of the synchronized flow at a traffic bottleneck. We have found that the larger the length of bottleneck, the higher the Hurst's exponent does as well as the stronger the correlations of the system. Applying our correlation analysis to traffic flow simulations with the NaSch model, which cannot reproduce synchronized flow of the three-phase theory, we have indeed found that the NaSch model does not exhibit long-range correlation characteristics found for synchronized flow.

  11. Normal ranges of heart rate and respiratory rate in children from birth to 18 years: a systematic review of observational studies

    PubMed Central

    Fleming, Susannah; Thompson, Matthew; Stevens, Richard; Heneghan, Carl; Plüddemann, Annette; Maconochie, Ian; Tarassenko, Lionel; Mant, David

    2013-01-01

    Summary Background Although heart rate and respiratory rate are routinely measured in children in acute settings, current reference ranges are not evidence-based. The aim of this study is to derive new centile charts for heart rate and respiratory rate using systematic review data from existing studies, and to compare these with existing international ranges. Methods We searched MEDLINE, EMBASE, and CINAHL to April 2009, and reference lists to identify studies which had measured heart rate and/or respiratory rate in normal children between birth and 18 years of age. We used a non-parametric kernel regression method to create centile charts for heart rate and respiratory rate with respect to age. We compared existing reference ranges with those derived from the centile charts. Findings We included 69 studies, 59 of which provided data on the heart rate of 143,346 children, and 20 on the respiratory rate of 3,881 children. Our new centile charts demonstrate the decline in respiratory rate from birth to early adolescence, with the steepest decline apparent in infants under two years; decreasing from a median of 44 breaths/minutes at birth to 26 breaths/minute at the age of two. The heart rate centile chart demonstrates a small peak at one month of age. The median heart rate increases from 127 beats/minute at birth to a maximum of 145 beats/minute at approximately one month of age, before decreasing to 113 beats/minute by the age of two. Comparison of the centile charts with existing published reference ranges for heart rate and respiratory rate show marked disagreement with the centile charts, with limits from published ranges frequently exceeding the 99th and 1st centiles, or crossing the median. Interpretation Our review shows that existing international guidelines for heart rate and respiratory rate in children are not based on evidence. We have created new centile charts based on a systematic review of studies which have measured these vital signs in normal

  12. Inflammation, But Not Telomere Length, Predicts Successful Ageing at Extreme Old Age: A Longitudinal Study of Semi-supercentenarians.

    PubMed

    Arai, Yasumichi; Martin-Ruiz, Carmen M; Takayama, Michiyo; Abe, Yukiko; Takebayashi, Toru; Koyasu, Shigeo; Suematsu, Makoto; Hirose, Nobuyoshi; von Zglinicki, Thomas

    2015-10-01

    To determine the most important drivers of successful ageing at extreme old age, we combined community-based prospective cohorts: Tokyo Oldest Old Survey on Total Health (TOOTH), Tokyo Centenarians Study (TCS) and Japanese Semi-Supercentenarians Study (JSS) comprising 1554 individuals including 684 centenarians and (semi-)supercentenarians, 167 pairs of centenarian offspring and spouses, and 536 community-living very old (85 to 99 years). We combined z scores from multiple biomarkers to describe haematopoiesis, inflammation, lipid and glucose metabolism, liver function, renal function, and cellular senescence domains. In Cox proportional hazard models, inflammation predicted all-cause mortality with hazard ratios (95% CI) 1.89 (1.21 to 2.95) and 1.36 (1.05 to 1.78) in the very old and (semi-)supercentenarians, respectively. In linear forward stepwise models, inflammation predicted capability (10.8% variance explained) and cognition (8(.)6% variance explained) in (semi-)supercentenarians better than chronologic age or gender. The inflammation score was also lower in centenarian offspring compared to age-matched controls with Δ (95% CI) = - 0.795 (- 1.436 to - 0.154). Centenarians and their offspring were able to maintain long telomeres, but telomere length was not a predictor of successful ageing in centenarians and semi-supercentenarians. We conclude that inflammation is an important malleable driver of ageing up to extreme old age in humans.

  13. Using natural range of variation to set decision thresholds: a case study for great plains grasslands

    USGS Publications Warehouse

    Symstad, Amy J.; Jonas, Jayne L.; Edited by Guntenspergen, Glenn R.

    2014-01-01

    Natural range of variation (NRV) may be used to establish decision thresholds or action assessment points when ecological thresholds are either unknown or do not exist for attributes of interest in a managed ecosystem. The process for estimating NRV involves identifying spatial and temporal scales that adequately capture the heterogeneity of the ecosystem; compiling data for the attributes of interest via study of historic records, analysis and interpretation of proxy records, modeling, space-for-time substitutions, or analysis of long-term monitoring data; and quantifying the NRV from those data. At least 19 National Park Service (NPS) units in North America’s Great Plains are monitoring plant species richness and evenness as indicators of vegetation integrity in native grasslands, but little information on natural, temporal variability of these indicators is available. In this case study, we use six long-term vegetation monitoring datasets to quantify the temporal variability of these attributes in reference conditions for a variety of Great Plains grassland types, and then illustrate the implications of using different NRVs based on these quantities for setting management decision thresholds. Temporal variability of richness (as measured by the coefficient of variation, CV) is fairly consistent across the wide variety of conditions occurring in Colorado shortgrass prairie to Minnesota tallgrass sand savanna (CV 0.20–0.45) and generally less than that of production at the same sites. Temporal variability of evenness spans a greater range of CV than richness, and it is greater than that of production in some sites but less in other sites. This natural temporal variability may mask undesirable changes in Great Plains grasslands vegetation. Consequently, we suggest that managers consider using a relatively narrow NRV (interquartile range of all richness or evenness values observed in reference conditions) for designating a surveillance threshold, at which

  14. Active Ageing and Active Citizenship in Liguria: A Case Study

    ERIC Educational Resources Information Center

    Palumbo, Mauro

    2014-01-01

    Liguria has the oldest age structure in Europe because of a low birth rate and long lifespans and therefore is a very interesting laboratory region in which to experiment with active ageing policies. The generations that are now approaching retirement hold a high level of personal and professional resources; so the "new" elderly people…

  15. Childhood bullying behaviors at age eight and substance use at age 18 among males. A nationwide prospective study.

    PubMed

    Niemelä, S; Brunstein-Klomek, A; Sillanmäki, L; Helenius, H; Piha, J; Kumpulainen, K; Moilanen, I; Tamminen, T; Almqvist, F; Sourander, A

    2011-03-01

    Childhood bullying behaviors (bullying and victimization) were studied as risk factors for substance use among Finnish males. The study design was a nationwide prospective general population study, where information was collected in 1989 and 1999. Bullying behaviors and childhood psychopathology at age eight were collected from teachers, parents and boys themselves. At age 18, self-reports of frequent drunkenness (once a week or more often), daily heavy smoking (10 cigarettes or more per day), and illicit drug use during the past six months were obtained from 78% of the boys attending the study at age eight (n=2946). Being frequently victimized at age eight predicted daily heavy smoking, and this was evident even after adjusting for childhood family background, psychopathology at age eight and at age 18, and other forms of substance use. In multivariate analysis, bullying others frequently predicted illicit drug use, while being a victim of bullying associated with a lower occurrence of illicit drug use. Bullying behaviors had no association with frequent drunkenness independent of other factors. Accordingly, being a victim of bullying predisposes in particular to subsequent smoking. Bullying others in childhood can be regarded as an early indicator to illicit drug use later in life. The screening and intervention possibilities in order to recognize the risk group for later health compromising behaviors are emphasized.

  16. High hand joint mobility is associated with radiological CMC1 osteoarthritis: the AGES-Reykjavik study

    PubMed Central

    Jónsson, H.; Elíasson, G. J.; Jónsson, Á.; Eiríksdóttir, G.; Sigurđsson, S.; Aspelund, T.; Harris, T. B.; Guđnason, V.

    2009-01-01

    Summary Objective Previous studies have indicated that joint hypermobility may affect the development of clinical and radiological hand osteoarthritis (OA), but this question has not been addressed in epidemiological studies. Our objective was to investigate this relationship in a population-based study. Patients and methods The study group consisted of 384 unselected older participants in the Age, Gene/Environment Susceptibility–Reykjavik Study (161 males, median age 76, range 69–90, and 223 females median age 75, range 69–92). The criterion used for joint mobility was the single maximal degree of hyperextension of digits 2 and 5 on both hands (HYP°). Results HYP° was more prevalent in females and on the left hand in both men and women. Both genders had a positive association between the degree of mobility measured by HYP° and radiological scores for the first carpometacarpal joint (CMC1) OA. Thus, those with HYP° ≥70 had an odds ratio of 3.05 (1.69–5.5, P < 0.001) of having a Kellgren–Lawrence score of ≥3 in a CMC1 joint. There was also a trend towards a negative association between HYP° and proximal interphalangeal joint scores. Conclusion Hand joint mobility, defined as hyperextension in the metacarpophalangeal joints (HYP°) is more prevalent in females and on the left side. It was associated with more severe radiographic OA in the CMC1 joints in this population. The reasons for this relationship are not known, but likely explanations involve ligament laxity and CMC1 joint stability. These findings may relate to the left-sided predominance of radiographic OA in the CMC1 joints observed in many prevalence studies. PMID:19010064

  17. A gravity study of the northern part of the Arctic National Wildlife Range, Alaska

    USGS Publications Warehouse

    Kososki, B.A.; Reiser, H.N.; Cavit, C.D.; Detterman, R.L.

    1978-01-01

    Interpretation of all publicly available onshore gravity data provides a basis for outlining regional elements of the basement and overlying structure in the northern part of the Arctic National Wildlife Range. Major post-Carboniferous sedimentary basins whose centers lie offshore on the Beaufort Shelf extend onshore in the northern part of the study area. There is strong evidence that dense basement rocks beneath these onshore extensions rise to relatively shallow depths along the northeast Alaskan coast. Geologic studies and interpretation of the gravity data indicate that the gross structural and stratigraphic framework of this area is similar to that of the Prudhoe Bay region to the west. A high potential for petroleum accumulation in the Wildlife Range is indicated by the surface presence of oil seeps, oil sands, and outcrops of reservoir and source rocks along the southern margins of the onshore basinal areas. Present data suggest that the greatest potential for onshore accumulations of hydrocarbons lies in the area south and east of Barter Island and that possibilities exist there for commercially substantial reserves. The potential of this area cannot be fully assessed, however, until the subsurface extent of several major unconformities is known. Unfortunately, gravity data alone are of little use in such determinations. South of the mountain front, large granitic intrusions are marked by a sharply defined gravity minimum. The subsurface distribution of these bodies could probably be mapped by detailed gravity surveys. Detailed aeromagnetic surveys should serve equally well for such a purpose.

  18. Dynamics of mtDNA introgression during species range expansion: insights from an experimental longitudinal study

    PubMed Central

    Mastrantonio, V.; Porretta, D.; Urbanelli, S.; Crasta, G.; Nascetti, G.

    2016-01-01

    Introgressive hybridization represents one of the long-lasting debated genetic consequences of species range expansion. Mitochondrial DNA has been shown to heavily introgress between interbreeding animal species that meet in new sympatric areas and, often, asymmetric introgression from local to the colonizing populations has been observed. Disentangling among the evolutionary and ecological processes that might shape this pattern remains difficult, because they continuously act across time and space. In this context, long-term studies can be of paramount importance. Here, we investigated the dynamics of mitochondrial introgression between two mosquito species (Aedes mariae and Ae. zammitii ) during a colonization event that started in 1986 after a translocation experiment. By analyzing 1,659 individuals across 25 years, we showed that introgression occurred earlier and at a higher frequency in the introduced than in the local species, showing a pattern of asymmetric introgression. Throughout time, introgression increased slowly in the local species, becoming reciprocal at most sites. The rare opportunity to investigate the pattern of introgression across time during a range expansion along with the characteristics of our study-system allowed us to support a role of demographic dynamics in determining the observed introgression pattern. PMID:27460445

  19. NOTE: Study of Gafchromic® EBT film response over a large dose range

    NASA Astrophysics Data System (ADS)

    Martišíková, Mária; Jäkel, Oliver

    2010-05-01

    Presently Gafchromic EBT films are widely used for relative dose verification in standard radiation therapy using high-energy photons, inclusive IMRT. The use of films for dosimetry in medical ion beams is more complicated due to the strongly inhomogeneous dose deposition by ions on microscopic level. Track structure models, presently used to describe dosimeter response as a function of the ion field properties, are based on input information which can be obtained from the film response in photon beams. We therefore studied the performance of Gafchromic EBT films, ancestors of currently available EBT2 films, in 60Co photon beams. The dose-response curve was measured from 7.5 × 10-2 Gy to 3 × 104 Gy. The dynamic range, linearity and dose rate dependence of this calibration curve were studied. A high saturation dose of 3 × 103 Gy, and thus a large dynamic range, was observed. No signs of supralinearity and bleaching due to radiation were found. No dependence of the response on the dose rate at high dose rates and high doses was found. All those properties justify the use of simplified models of the film response to ions. Furthermore, fits of the calibration data by predictions of different models for signal creation mechanism of dosimetric materials were performed. The best description was found for the recently published gamma-distributed single-hit model which takes into account different sizes of the active centres.

  20. Study of Particle Motion in He II Counterflow Across a Wide Heat Flux Range

    NASA Astrophysics Data System (ADS)

    Mastracci, Brian; Takada, Suguru; Guo, Wei

    2017-01-01

    Some discrepancy exists in the results of He II counterflow experiments obtained using particle image velocimetry (PIV) when compared with those obtained using particle tracking velocimetry (PTV): using PIV, it was observed that tracer particles move at roughly half the expected normal fluid velocity, v_n/2 , while tracer particles observed using PTV moved at approximately v_n . A suggested explanation is that two different flow regimes were examined since the range of heat flux applied in each experiment was adjacent but non-overlapping. Another PTV experiment attempted to test this model, but the applied heat flux did not overlap with any PIV experiments. We report on the beginnings of a study of solid D_2 particle motion in counterflow using PTV, and the heat flux range overlaps that of all previous visualization studies. The observed particle velocity distribution transitions from a two-peak structure to a single peak as the heat flux is increased. Furthermore, the mean value of one peak in the bi-modal distributions grows at approximately the same rate as v_n , while the mean value of the single-peak distributions grows at roughly 0.4v_n , in reasonable agreement with both previous experiments and with the suggested model.

  1. Is self-massage an effective joint range-of-motion strategy? A pilot study.

    PubMed

    Monteiro, Estêvão Rios; Cavanaugh, Mark Tyler; Frost, David Michael; Novaes, Jefferson da Silva

    2017-01-01

    Increases in joint range of motion may be beneficial in both improving performance and reducing the risk of injury. The purpose of this study was to investigate short-term changes in passive hip flexion (HF) and extension (HE) after foam rolling (FR) and roller massage (RM) durations of 60 and 120s. Ten recreationally active men (27.6 ± 2.4 years old; 164.8 ± 6.6 cm; 62.2 ± 8.0 kg; 24.2 ± 2.1 m(2)/kg) were recruited for this study. Subjects performed foam rolling (FR) and roller massage (RM) on the hamstrings for 60 (FR60 and RM60) and 120 (FR120 and RM120) seconds. Significant differences between FR120 and RM60 were observed in both HF (p < 0.001) and HE (p < 0.001) suggesting an intervention (roller style) effect. Furthermore, significant differences (p < 0.001) between RM60 and RM120 suggest a dosage based response. Thus, the findings indicate that different roller type or rolling volume may affect range-of-motion.

  2. Age 60 Study, Part 2: Airline Pilot Age and Performance - A Review of the Scientific Literature

    DTIC Science & Technology

    1994-10-01

    accomplish the research objectives of Tasks 4 and 5 of the Age 60 Project, two preliminary steps must be taken. Step 1 is to develop a high -level...investigate an information processing model of pilot decision making that takes into account pilot experience and stress. They found that low and high ...the third of a year (grouping months 1, 4 , 7 and 10; months 2, 5, 8, and 11; and months 3, 6, 9, and 12) before computing accident rates. Then three

  3. Study of special ceramics with a dilatometer in the temperature range 25 2000°C

    NASA Astrophysics Data System (ADS)

    Kaisersberger, E.; Kelly, J.

    1989-03-01

    Many properties of special ceramic materials, often closely related, such as sintering temperature, shrinkage in firing, mineral reaction, and strength can be studied with thermal analysis. Also the influence of type, structure, and preparation of raw materials and, of plasticizers and binding materials for forming and compressing, as well as the compatibility with protective coatings (glazes, varnishes, metal films), are investigated by thermal analysis. The development of a new dilatometer for the temperature range 25 2000°C with maximum heating rates of 20 K·min-1 and sample sizes 25 50 mm in length and 6 12 mm in diameter for measurements in an argon atmosphere and vacuum has opened up new horizons. Sintering studies at high temperatures are described.

  4. A large-scale candidate-gene association study of age at menarche and age at natural menopause

    PubMed Central

    Kraft, Peter; Chasman, Daniel I.; Buring, Julie E.; Chen, Constance; Hankinson, Susan E.; Paré, Guillaume; Chanock, Stephen; Ridker, Paul M.; Hunter, David J.

    2010-01-01

    Recent genome-wide association (GWA) studies have identified several novel genetic loci associated with age at menarche and age at natural menopause. However, the stringent significance threshold used in GWA studies potentially lead to false negatives and true associations may have been overlooked. Incorporating biologically relevant information, we examined whether common genetic polymorphisms in candidate genes of 9 groups of biologically plausible pathways and related phenotypes are associated with age at menarche and age at natural menopause. A total of 18,862 genotyped and imputed single nucleotide polymorphisms (SNPs) in 278 genes were assessed for their associations with these two traits among a total of 24,341 women from the Nurses’ Health Study (NHS, N=2,287) and the Women’s Genome Health Study (WGHS, N=22,054). Linear regression was used to assess the marginal association of each SNP with each phenotype. We adjusted for multiple testing within each gene to identify statistically significant SNP associations at the gene level. To evaluate the overall evidence for an excess of statistically significant gene associations over the proportion expected by chance, we applied a one-sample test of proportion to each group of candidate genes. The steroid-hormone metabolism and biosynthesis pathway was found significantly associated with both age at menarche and age at natural menopause (p=0.040 and 0.011, respectively). Additionally, the group of genes associated with precocious or delayed puberty was found significantly associated with age at menarche (p=0.013), and the group of genes involved in premature ovarian failure with age at menopause (p=0.025). PMID:20734064

  5. Serum Thyroid Function, Mortality and Disability in Advanced Old Age: The Newcastle 85+ Study

    PubMed Central

    Razvi, Salman; Yadegarfar, Mohammad E.; Martin-Ruiz, Carmen; Kingston, Andrew; Collerton, Joanna; Visser, Theo J.; Kirkwood, Tom B.; Jagger, Carol

    2016-01-01

    Context: Perturbations in thyroid function are common in older individuals but their significance in the very old is not fully understood. Objective: This study sought to determine whether thyroid hormone status and variation of thyroid hormones within the reference range correlated with mortality and disability in a cohort of 85-year-olds. Design: A cohort of 85-year-old individuals were assessed in their own homes (community or institutional care) for health status and thyroid function, and followed for mortality and disability for up to 9 years. Setting and Participants: Six hundred and forty-three 85-year-olds registered with participating general practices in Newcastle and North Tyneside, United Kingdom. Main Outcomes: All-cause mortality, cardiovascular mortality, and disability according to thyroid disease status and baseline thyroid hormone parameters (serum TSH, FT4, FT3, and rT3). Models were adjusted for age, sex, education, body mass index, smoking, and disease count. Results: After adjustment for age and sex, all-cause mortality was associated with baseline serum rT3 and FT3 (both P < .001), but not FT4 or TSH. After additional adjustment for potential confounders, only rT3 remained significantly associated with mortality (P = .001). Baseline serum TSH and rT3 predicted future disability trajectories in men and women, respectively. Conclusions: Our study is reassuring that individuals age 85 y with both subclinical hypothyroidism and subclinical hyperthyroidism do not have a significantly worse survival over 9 years than their euthyroid peers. However, thyroid function tests did predict disability, with higher serum TSH levels predicting better outcomes. These data strengthen the argument for routine use of age-specific thyroid function reference ranges. PMID:27552542

  6. Muscle biopsy as a tool in the study of aging.

    PubMed

    Coggan, A R

    1995-11-01

    The needle biopsy procedure provides a minimally invasive means of obtaining small samples of skeletal muscle from human volunteers. Such samples can be used to examine a variety of structural and functional characteristics of muscle, including fiber type and size, capillarization, enzymatic capacities, energy substrate or protein/mRNA concentrations, metabolic responses, and contractile properties. In conjunction with other methods, biopsy sampling can also be used to estimate total muscle mass and fiber number, and to determine rates of protein synthesis and degradation. Optimal handling and storage conditions vary widely, but in general, most of the above measurements can be made using frozen tissue, so that samples can be stored almost indefinitely. The procedure is also safe and generally well-tolerated, making it possible to perform longitudinal studies of the same person. The biopsy technique is therefore well suited for examining the underlying physiological mechanisms responsible for muscle wasting in the elderly, as well as for assessing the effects of nutritional, hormonal, and/or lifestyle (e.g., exercise) interventions intended to combat this problem. Although sample size limitations have been largely overcome by the development of microtechniques, more information is needed on how to minimize the variability introduced by studying only a small fraction of the whole muscle. Studies are also required to determine whether it is sufficient to biopsy only one muscle (and if so, which is optimal), or whether there are differential effects of aging in various muscle groups that would preclude extrapolating from one muscle to all muscles in the body.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Development of a Detonation Profile Test for Studying Aging Effects in LX-17

    SciTech Connect

    Tran, T; Lewis, P; Tarver, C; Maienschein, J; Druce, R; Lee, R; Roeske, F

    2002-03-25

    A new small-scale Detonation Profile Test (DPT) is being developed to investigate aging effects on the detonation behavior of insensitive high explosives. The experiment involves initiating a small LX-17 cylindrical charge (12.7-19.1 mm diameter x 25.4-33 mm long) and measuring the velocity and curvature of the emerging detonation wave using a streak camera. Results for 12.7 mm diameter unconfined LX-17 charges show detonation velocity in the range between 6.79 and 7.06 km/s for parts up to 33 mm long. Since LX-17 can not sustain detonation at less than 7.3 km/s, these waves were definitely failing. Experiments with confined 12.7 mm diameter and unconfined 19.1 mm diameter samples showed wave velocities in the range of 7.4-7.6 km/s, values approaching steady state conditions at infinite diameter. Experiments with unconfined 19.1 mm diameter specimens are expected to provide reproducible and useful range of detonation parameters suitable for studying aging effects.

  8. Another stage of development: Biological degeneracy and the study of bodily ageing.

    PubMed

    Mason, Paul H; Maleszka, Ryszard; Dominguez D, Juan F

    2016-12-21

    Ageing is a poorly understood process of human development mired by a scientific approach that struggles to piece together distributed variable factors involved in ongoing transformations of living systems. Reconfiguring existing research paradigms, we review the concept of 'degeneracy', which has divergent popular and technical definitions. The technical meaning of degeneracy refers to the structural diversity underlying functional plasticity. Degeneracy is a distributed system property that can be observed within individual brains or across different brains. For example, dementias with similar behavioural anomalies can result from a diverse range of cellular "faults", which is an example of degeneracy because the symptoms are similar in spite of different underlying mechanisms. Degeneracy is a valuable epistemological tool that can transformatively enhance scientific models of bodily ageing. We propose that movement science is one of the first areas that can productively integrate degeneracy into models of bodily ageing. We also propose model organisms such as eusocial honey bees in which degeneracy can be studied at the molecular and cellular level. Developing a vocabulary for thinking about how distributed variable factors are interlinked is important if we are to understand bodily ageing not as a single entity, but as the heterogeneous construction of changing biological, social, and environmental processes.

  9. Adopted cognitive tests for gerbils: validation by studying ageing and ischemia.

    PubMed

    Wappler, Edina A; Szilágyi, Géza; Gál, Anikó; Skopál, Judit; Nyakas, Csaba; Nagy, Zoltán; Felszeghy, Klára

    2009-04-20

    Transient occlusion of common carotid arteries in gerbils is a simple and widely used model for assessing histological and functional consequences of transient forebrain ischemia and neuroprotective action of pharmaceuticals. In the present study we aimed to introduce additional behavioural tests as novel object recognition and food-motivated hole-board learning in order to measure attention and learning capacity in gerbils. For validating these cognitive tests the effects of ageing (4, 9 and 18 months) and those of transient forebrain ischemia induced by bilateral carotid occlusion at 9 months of age were investigated. Neuronal cell death was estimated in the hippocampus using TUNEL and caspase-3 double fluorescence labelling and confocal microscopy. Ageing within the selected range although influenced ambulatory activity, did not considerably change attention and memory functions of gerbils. As a result of transient ischemia a selective neuronal damage in CA1 and CA2 regions of the hippocampus has been observed and tested 4 days after the insult. Ischemic gerbils became hyperactive, but showed decreased attention and impaired spatial memory functions as compared to sham-operated controls. According to our results the novel object recognition paradigm and the hole-board spatial learning test could reliably be added to the battery of conventional behavioural tests applied previously in this species. The novel tests can be performed within a wide interval of adult age and provide useful additional methods for assessing ischemia-induced cognitive impairment in gerbils.

  10. A meta-analysis of home range studies in the context of trophic levels: Implications for policy-based conservation

    PubMed Central

    Diepstraten, Rianne; Jessen, Tyler

    2017-01-01

    Home ranges have been widely-used as ecological tools, though using home range estimates in decision-support for conservation biology is a relatively new idea. However, trophic levels are rarely taken into consideration when estimating home range. This lapse could present issues when interpreting past studies, especially in policy-based conservation. The objectives of this study were to survey the current literature, to critically analyse published articles with home range analyses, and to compare home range size by species’ trophic level. We predicted that animals residing in higher trophic levels would have significantly larger home ranges than animals occupying lower trophic levels. We found that terrestrial carnivores had larger home ranges than terrestrial herbivores, though terrestrial mesocarnivores had the largest home ranges. We also found that aquatic herbivores had larger home ranges than both aquatic carnivores and aquatic mesocarnivores. Our results are important to consider for planning and management sectors, to avoid the implementation of ineffective conservation policies. PMID:28267759

  11. A meta-analysis of home range studies in the context of trophic levels: Implications for policy-based conservation.

    PubMed

    Fauvelle, Catherine; Diepstraten, Rianne; Jessen, Tyler

    2017-01-01

    Home ranges have been widely-used as ecological tools, though using home range estimates in decision-support for conservation biology is a relatively new idea. However, trophic levels are rarely taken into consideration when estimating home range. This lapse could present issues when interpreting past studies, especially in policy-based conservation. The objectives of this study were to survey the current literature, to critically analyse published articles with home range analyses, and to compare home range size by species' trophic level. We predicted that animals residing in higher trophic levels would have significantly larger home ranges than animals occupying lower trophic levels. We found that terrestrial carnivores had larger home ranges than terrestrial herbivores, though terrestrial mesocarnivores had the largest home ranges. We also found that aquatic herbivores had larger home ranges than both aquatic carnivores and aquatic mesocarnivores. Our results are important to consider for planning and management sectors, to avoid the implementation of ineffective conservation policies.

  12. Ethno Medical Studies In Kailasagirikona Forest Range Of Chittoor District, Andhra Pradesh

    PubMed Central

    Pratap, Goli Panchala; Prasad, G.P.; Sudarsanam, G.

    2009-01-01

    The present study reveals the Ethno Botanical studies on uses of medicinal plants in Kailasagiri forest range of Chittoor district, Andhra Pradesh. Role of these studies in rural and forest economies is immense. Tribal people of this area have authentic information on medicinal values of different plant parts like leaves, fruits, flowers, seeds, stem bark, tubers and roots. They have been using these parts in the form of paste, powder, juice, decoction, infusion and also in crude form, with other additives like ghee, sesame oil and goat milk, to relieve from different ailments. The present study brought to the light the immense hidden knowledge of Tribal people towards medicinal plants. Present study discloses the ethnic practices of 52 species belonging to 37 families to relieve different ailments like Skin diseases, Jaundice, Rheumatism, Burning micturation, Fevers, Intestinal worms, Menstrual problems ,Cough, Diarrhea, Head-ache, Cold, Diabetes, Tooth-ache, Asthma, Ear-ache, Eye diseases, Dandruff, Stomach-ache, Insomnia, Indigestion , Piles, Constipation, Cuts, wounds ,Abscesses, Sexual problems, Fractures, Galactagogue, Leprosy and Antidotes, Hair tonics, Abortificients, anti Abortifacients, Lice eradicators and Nasal drops. PMID:22557350

  13. Organic tanks safety program FY95 waste aging studies

    SciTech Connect

    Camaioni, D.M.; Samuels, W.D.; Clauss, S.A.; Lenihan, B.D.; Wahl, K.L.; Campbell, J.A.; Shaw, W.J.

    1995-09-01

    This report gives the second year`s findings of a study of how thermal and radiological processes may change the composition of organic compounds in the underground tanks at Hanford. Efforts were focused on the global reaction kinetics in a simulated waste exposed to {gamma} rays and the reactions of organic radicals with nitrite ion. The gas production is predominantly radiolytic. Decarboxylation of carboxylates is probably an aging pathway. TBP was totaly consumed in almost every run. Radiation clearly accelerated consumption of the other compounds. EDTA is more reactive than citrate. Oximes and possibly organic nitro compounds are key intermediates in the radiolytic redox reactions of organic compounds with nitrate/nitrite. Observations are consistent with organic compounds being progressively degraded to compounds with greater numbers of C-O bonds and fewer C-H and C-C bonds, resulting in an overall lower energy content. If the radwaste tanks are adequately ventilated and continually dosed by radioactivity, their total energy content should have declined. Level of risk depends on how rapidly carboxylate salts of moderate energy content (including EDTA fragments) degrade to low energy oxalate and formate.

  14. Survey data for the study of aging in Latin America and the Caribbean: selected studies.

    PubMed

    Wong, Rebeca; Peláez, Martha; Palloni, Alberto; Markides, Kyriakos

    2006-04-01

    The article summarizes three of the data collection studies that can assist researchers in examining population aging processes in the Latin America and Caribbean region with an emphasis on cross-national comparisons, including the population of Mexican immigrants in the United States. These are the Survey on Health and Wellbeing of Elders conducted in seven urban centers of the region, the national Mexican Health and Aging Study, and the Hispanic Established Populations for Epidemiologic Studies of the Elderly in the United States. The article describes the studies and marks them as informative, comprehensive, and still underanalyzed in particular for the purpose of cross-national analyses of aging among Latin American and Caribbean populations.

  15. The Effect of Donor Age on Corneal Transplantation Outcome: Results of the Cornea Donor Study

    PubMed Central

    2009-01-01

    Objective To determine whether graft survival over a 5-year follow-up period using corneal tissue from donors older than 65 years of age is similar to graft survival using corneas from younger donors. Design Multi-center prospective, double-masked, controlled clinical trial Participants 1090 subjects undergoing corneal transplantation for a moderate risk condition (principally Fuchs’ dystrophy or pseudophakic corneal edema); 11 subjects with ineligible diagnoses were not included Methods 43 participating eye banks provided corneas from donors in the age range of 12 to 75 with endothelial cell densities of 2300 to 3300 cells/mm2, using a random approach without respect to recipient factors. The 105 participating surgeons at 80 sites were masked to information about the donor cornea including donor age. Surgery and post-operative care were performed according to the surgeons’ usual routines. Subjects were followed for five years. Main Outcome Measures Graft failure, defined as a regraft or a cloudy cornea that was sufficiently opaque as to compromise vision for a minimum of three consecutive months. Results The 5-year cumulative probability of graft survival was 86% in both the <66.0 donor age group and the ≥66.0 donor age group (difference = 0%, upper limit of one-sided 95% confidence interval = 4%). In a statistical model with donor age as a continuous variable, there was not a significant relationship between donor age and outcome (P=0.11). Three graft failures were due to primary donor failure, 8 to uncorrectable refractive error, 48 to graft rejection, 46 to endothelial decompensation (23 of which had a prior, resolved episode of probable or definite graft rejection), and 30 to other causes. The distribution of the causes of graft failure did not differ between donor age groups. Conclusions Five-year graft survival for cornea transplants at moderate risk for failure is similar using corneas from donors ≥ 66.0 years and donors < 66.0 years. Surgeons and

  16. On Road Study of Colorado Front Range Greenhouse Gases Distribution and Sources

    NASA Astrophysics Data System (ADS)

    Petron, G.; Hirsch, A.; Trainer, M. K.; Karion, A.; Kofler, J.; Sweeney, C.; Andrews, A.; Kolodzey, W.; Miller, B. R.; Miller, L.; Montzka, S. A.; Kitzis, D. R.; Patrick, L.; Frost, G. J.; Ryerson, T. B.; Robers, J. M.; Tans, P.

    2008-12-01

    The Global Monitoring Division and Chemical Sciences Division of the NOAA Earth System Research Laboratory have teamed up over the summer 2008 to experiment with a new measurement strategy to characterize greenhouse gases distribution and sources in the Colorado Front Range. Combining expertise in greenhouse gases measurements and in local to regional scales air quality study intensive campaigns, we have built the 'Hybrid Lab'. A continuous CO2 and CH4 cavity ring down spectroscopic analyzer (Picarro, Inc.), a CO gas-filter correlation instrument (Thermo Environmental, Inc.) and a continuous UV absorption ozone monitor (2B Technologies, Inc., model 202SC) have been installed securely onboard a 2006 Toyota Prius Hybrid vehicle with an inlet bringing in outside air from a few meters above the ground. To better characterize point and distributed sources, air samples were taken with a Portable Flask Package (PFP) for later multiple species analysis in the lab. A GPS unit hooked up to the ozone analyzer and another one installed on the PFP kept track of our location allowing us to map measured concentrations on the driving route using Google Earth. The Hybrid Lab went out for several drives in the vicinity of the NOAA Boulder Atmospheric Observatory (BAO) tall tower located in Erie, CO and covering areas from Boulder, Denver, Longmont, Fort Collins and Greeley. Enhancements in CO2, CO and destruction of ozone mainly reflect emissions from traffic. Methane enhancements however are clearly correlated with nearby point sources (landfill, feedlot, natural gas compressor ...) or with larger scale air masses advected from the NE Colorado, where oil and gas drilling operations are widespread. The multiple species analysis (hydrocarbons, CFCs, HFCs) of the air samples collected along the way bring insightful information about the methane sources at play. We will present results of the analysis and interpretation of the Hybrid Lab Front Range Study and conclude with perspectives

  17. [Studies of the biological age in adult taiga ticks Ixodes persulcatus (Ixodinae)].

    PubMed

    Grigor'eva, L A

    2013-01-01

    The history of studies of the biological age in ixodid ticks is discussed. A method of estimation of the biological age in adult ticks of the genus Ixodes by the degree of fat inclusions in midgut cells and in the fat body is developed. An "age scale" for the determination of the calendar age was assumed.

  18. Positron range in tissue-equivalent materials: experimental microPET studies.

    PubMed

    Alva-Sánchez, H; Quintana-Bautista, C; Martínez-Dávalos, A; Ávila-Rodríguez, M A; Rodríguez-Villafuerte, M

    2016-09-07

    In this work an experimental investigation was carried out to study the effect that positron range has over positron emission tomography (PET) scans through measurements of the line spread function (LSF) in tissue-equivalent materials. Line-sources consisted of thin capillary tubes filled with (18)F, (13)N or (68)Ga water-solution inserted along the axis of symmetry of cylindrical phantoms constructed with the tissue-equivalent materials: lung (inhale and exhale), adipose tissue, solid water, trabecular and cortical bone. PET scans were performed with a commercial small-animal PET scanner and image reconstruction was carried out with filtered-backprojection. Line-source distributions were analyzed using radial profiles taken on axial slices from which the spatial resolution was determined through the full-width at half-maximum, tenth-maximum, twentieth-maximum and fiftieth-maximum. A double-Gaussian model of the LSFs was used to fit experimental data which can be incorporated into iterative reconstruction methods. In addition, the maximum activity concentration in the line-sources was determined from reconstructed images and compared to the known values for each case. The experimental data indicates that positron range in different materials has a strong effect on both spatial resolution and activity concentration quantification in PET scans. Consequently, extra care should be taken when computing standard-uptake values in PET scans, in particular when the radiopharmaceutical is taken up by different tissues in the body, and more even so with high-energy positron emitters.

  19. Comparative studies on plant range size: Linking reproductive and regenerative traits in two Ipomoea species

    NASA Astrophysics Data System (ADS)

    Astegiano, Julia; Funes, Guillermo; Galetto, Leonardo

    2010-09-01

    Reproductive and regenerative traits associated with colonization and persistence ability may determine plant range size. However, few comparative studies on plant distribution have assessed these traits simultaneously. Pollinator richness and frequency of visits, autonomous self-pollination ability, reproductive output (i.e., reproductive traits), seed bank strategy and seedling density (i.e., regenerative traits) were compared between the narrowly distributed Ipomoea rubriflora O'Donnell (Convolvulaceae) and its widespread congener Ipomoea purpurea (L.) Roth. The narrowly distributed species showed higher ecological specialization to pollinators and lower autonomous self-pollination ability. Frequency of visits, natural seed/ovule ratio and fruit set, and total fruit production did not differ between species. However, the number of seeds produced per fruit was lower in the narrowly distributed species, translating into lower total seed production per plant. Indeed, I. rubriflora formed smaller transient and persistent seed banks and showed lower seedling density than the widespread I. purpurea. These reproductive and regenerative trait results suggest that the narrowly distributed species may have lower colonization and persistence ability than its widespread congener. They further suggest that the negative effects of lower fecundity in the narrowly distributed species might persist in time through the long-lasting effects of total seed production on seed bank size, reducing the species' ability to buffered environmental stochasticity. However, other regenerative traits, such as seed size, and processes such as pre- and post-dispersal seed predation, might modulate the effects of plant fecundity on plant colonization and persistence ability and thus range size.

  20. Novel Acoustic Technology for Studying Free-Ranging Shark Social Behaviour by Recording Individuals' Interactions

    PubMed Central

    Guttridge, Tristan L.; Gruber, Samuel H.; Krause, Jens; Sims, David W.

    2010-01-01

    Group behaviours are widespread among fish but comparatively little is known about the interactions between free-ranging individuals and how these might change across different spatio-temporal scales. This is largely due to the difficulty of observing wild fish groups directly underwater over long enough time periods to quantify group structure and individual associations. Here we describe the use of a novel technology, an animal-borne acoustic proximity receiver that records close-spatial associations between free-ranging fish by detection of acoustic signals emitted from transmitters on other individuals. Validation trials, held within enclosures in the natural environment, on juvenile lemon sharks Negaprion brevirostris fitted with external receivers and transmitters, showed receivers logged interactions between individuals regularly when sharks were within 4 m (∼4 body lengths) of each other, but rarely when at 10 m distance. A field trial lasting 17 days with 5 juvenile lemon sharks implanted with proximity receivers showed one receiver successfully recorded association data, demonstrating this shark associated with 9 other juvenile lemon sharks on 128 occasions. This study describes the use of acoustic underwater proximity receivers to quantify interactions among wild sharks, setting the scene for new advances in understanding the social behaviours of marine animals. PMID:20174465

  1. Positron range in tissue-equivalent materials: experimental microPET studies

    NASA Astrophysics Data System (ADS)

    Alva-Sánchez, H.; Quintana-Bautista, C.; Martínez-Dávalos, A.; Ávila-Rodríguez, M. A.; Rodríguez-Villafuerte, M.

    2016-09-01

    In this work an experimental investigation was carried out to study the effect that positron range has over positron emission tomography (PET) scans through measurements of the line spread function (LSF) in tissue-equivalent materials. Line-sources consisted of thin capillary tubes filled with 18F, 13N or 68Ga water-solution inserted along the axis of symmetry of cylindrical phantoms constructed with the tissue-equivalent materials: lung (inhale and exhale), adipose tissue, solid water, trabecular and cortical bone. PET scans were performed with a commercial small-animal PET scanner and image reconstruction was carried out with filtered-backprojection. Line-source distributions were analyzed using radial profiles taken on axial slices from which the spatial resolution was determined through the full-width at half-maximum, tenth-maximum, twentieth-maximum and fiftieth-maximum. A double-Gaussian model of the LSFs was used to fit experimental data which can be incorporated into iterative reconstruction methods. In addition, the maximum activity concentration in the line-sources was determined from reconstructed images and compared to the known values for each case. The experimental data indicates that positron range in different materials has a strong effect on both spatial resolution and activity concentration quantification in PET scans. Consequently, extra care should be taken when computing standard-uptake values in PET scans, in particular when the radiopharmaceutical is taken up by different tissues in the body, and more even so with high-energy positron emitters.

  2. A Range Correction for Icesat and Its Potential Impact on Ice-sheet Mass Balance Studies

    NASA Technical Reports Server (NTRS)

    Borsa, A. A.; Moholdt, G.; Fricker, H. A.; Brunt, Kelly M.

    2014-01-01

    We report on a previously undocumented range error in NASA's Ice, Cloud and land Elevation Satellite (ICESat) that degrades elevation precision and introduces a small but significant elevation trend over the ICESat mission period. This range error (the Gaussian-Centroid or 'G-C'offset) varies on a shot-to-shot basis and exhibits increasing scatter when laser transmit energies fall below 20 mJ. Although the G-C offset is uncorrelated over periods less than1 day, it evolves over the life of each of ICESat's three lasers in a series of ramps and jumps that give rise to spurious elevation trends of -0.92 to -1.90 cm yr(exp -1), depending on the time period considered. Using ICESat data over the Ross and Filchner-Ronne ice shelves we show that (1) the G-C offset introduces significant biases in ice-shelf mass balance estimates, and (2) the mass balance bias can vary between regions because of different temporal samplings of ICESat.We can reproduce the effect of the G-C offset over these two ice shelves by fitting trends to sample-weighted mean G-C offsets for each campaign, suggesting that it may not be necessary to fully repeat earlier ICESat studies to determine the impact of the G-C offset on ice-sheet mass balance estimates.

  3. Economic Promises and Challenges of Productive Resources: A Study of Man's Use of Productive Resources over the Ages (From the Stone Age to the Space Age).

    ERIC Educational Resources Information Center

    Bourbonnais, Mary Kathryn

    Research and study of economic discoveries, inventions, improvements, and man's use of natural and human resources and capital goods from the Stone Age to the present helped fifth graders understand and appreciate the foundation and structure of the U.S. economic system and today's standards of living. The year-long study, which was integrated…

  4. Ethnoveterinary Study of Medicinal Plants in a Tribal Society of Sulaiman Range

    PubMed Central

    Tariq, Akash; Mussarat, Sakina; Adnan, Muhammad; AbdElsalam, Naser M.; Ullah, Riaz; Khan, Abdul Latif

    2014-01-01

    The aims of the present study were (i) to document ethnoveterinary plants and their formulation techniques in an unexplored region of Pakistan and (ii) to select candidate medicinal plants with high consensus factor and fidelity value for further in vitro investigation. A total of 60 informants were interviewed using semistructured questionnaire. A total of 41 plants belonging to 30 families were used to treat livestock ailments in study area. Mostly leaves (47%) were used in recipes formulation mostly in the form of decoction. Gastrointestinal infections were found more common and majority of the plants were used against cow (31) and buffaloes (24) ailments. Recovery time of majority of the recipes was three to four days. Informant consensus factor (Fic) results have shown a high degree of consensus for gastrointestinal, respiratory, and reproductive (0.95 each) ailments. Fidelity level (FL) results showed that Asparagus gracilis ranked first with FL value 93% followed by Rumex hastatus ranked second (91%) and Tinospora cordifolia ranked third (90%). Aged farmers and nomads had more traditional knowledge as compared to younger ones. Plants with high Fic and FL values could be further investigated in vitro for the search of some novel bioactive compounds and young generation should be educated regarding ethnoveterinary practices. PMID:25405212

  5. Age and sexually dimorphic changes in costal cartilages. A preliminary microscopic study.

    PubMed

    Rejtarová, Olga; Hejna, Petr; Soukup, Tomás; Kuchar, Michal

    2009-12-15

    This study reports changes in costal cartilages that appear at the microscopic level throughout life, especially during the ossification process. The work builds on the results of our previous X-ray study, which confirmed the presence of two sexually dimorphic ossification patterns. This led to questions about the existence of additional sex-specific patterns that relate to the ossification process in costal cartilages. Samples of costal cartilages and adjacent parts of the bones were obtained from the autopsies of 17 corpses. The age range among the cadavers varied greatly, from a newborn baby to 91 years of age. Sections of costal cartilage were routinely processed and stained. Alkaline phosphatase activity was detected using histochemical methods. Collagens type II and X were detected immunohistochemically by monoclonal antibodies. The results of our study show that ossification of costal cartilages can take place in the form of two individual processes, localization and time-separate. Endochondral ossifications in the region of the costochondral zone appear in the first decade, and they correspond to ossifications detected by X-ray in the second decade. The location of sex-specific ossifications is determined by the penetration of cartilage canals into the metaphysial part of the rib. Endochondral intramembranous ossifications in the reserve zone appear after the third decade. These types of ossifications correspond to central globular ossifications detected by X-ray, and they are not sexually dimorphic. They can serve for accurate estimation of age.

  6. Making heads or tails of mitochondrial membranes in longevity and aging: a role for comparative studies

    PubMed Central

    2014-01-01

    Mitochondria play vital roles in metabolic energy transduction, intermediate molecule metabolism, metal ion homeostasis, programmed cell death and regulation of the production of reactive oxygen species. As a result of their broad range of functions, mitochondria have been strongly implicated in aging and longevity. Numerous studies show that aging and decreased lifespan are also associated with high reactive oxygen species production by mitochondria, increased mitochondrial DNA and protein damage, and with changes in the fatty acid composition of mitochondrial membranes. It is possible that the extent of fatty acid unsaturation of the mitochondrial membrane determines susceptibility to lipid oxidative damage and downstream protein and genome toxicity, thereby acting as a determinant of aging and lifespan. Reviewing the vast number of comparative studies on mitochondrial membrane composition, metabolism and lifespan reveals some evidence that lipid unsaturation ratios may correlate with lifespan. However, we caution against simply relating these two traits. They may be correlative but have no functional relation. We discuss an important methodology for body mass and phylogenetic correction in comparative studies. PMID:24588808

  7. Spectral studies of comets in the ultraviolet range and prospects of the WSO-UV project in these studies

    NASA Astrophysics Data System (ADS)

    Sachkov, M. E.

    2016-07-01

    Many problems of determining the chemical composition of comets and studying the physical processes in cometary nuclei can only be solved by using observational data in the UV range of the electromagnetic spectrum (115-300 nm). Cometary observations have a number of features in comparison with such studies of other astronomical objects. The World Space Observatory — Ultraviolet mission, planned for launch in 2021, will overcome most of the challenges in these studies and will be able to become an essential tool of cometary UV research in the following decade.

  8. Managers' summary - ecological studies of the Pryor Mountain Wild Horse Range, 1992-1997

    USGS Publications Warehouse

    Singer, F.J.; Schoenecker, K.A.

    2000-01-01

    Ecological Studies of the Pryor Mountain Wild Horse Range, 1992-1997 provides a synthesis of key findings of landscape-scale, interdisciplinary studies of the effects of wild horses and native ungulates on a rugged, mountain ecosystem. This is perhaps the most comprehensive study of a wild horse herd conducted. This was a complex study and one involving a truly interagency approach. Six agencies either provided input to research priority setting, funding, or both. The agencies included the Bureau of Land Management, National Park Service, U.S. Geological Survey, Montana Department of Fish, Wildlife and Parks, Wyoming Game and Fish Department, and U.S. Forest Service. The major research direction and effort came from the U.S. Geological Survey and Natural Resources Ecology Lab, Colorado State University with Montana State University and the University of Kentucky also participating. Ungulate monitoring was conducted by the U.S. Geological Survey, Biological Resources Division, Bureau of Land Management, Billings Field Office and the Montana Fish and Wildlife Parks, with funding by Bighorn Canyon National Recreation Area. Many other individuals and groups were involved and deserve credit. The report printing was made possible with funds from the Bureau of Land Management, Wild Horse and Burro Program, Washington Office. This report was prepared by the Information Management Project, Midcontinent Ecological Science Center, U.S. Geological Survey.

  9. Ray-tracing studies of fast waves in the lower hybrid range of frequencies

    NASA Astrophysics Data System (ADS)

    Dittman, A.; Pinsker, R. I.

    2016-10-01

    Fast waves in the lower-hybrid range of frequencies, also referred to as `whistlers' or `helicons', will be used in the DIII-D tokamak for off-axis non-inductive current drive. Ray-tracing studies have shown that the required off-axis deposition can be achieved in target plasmas that have been recently studied in DIII-D. We wish to characterize the sensitivity of the rf power deposition profile to details of the equilibrium, and are thereby motivated to re-examine the fundamentals of ray-tracing in this regime. We have studied ray-tracing in the vicinity of regular turning points (cut-offs) and mode-coupling points in simple geometries (slab, cylinder). Later phases of the work will use the GENRAY code to study the effect of strong magnetic shear in the outer region of the plasma on the shape of the ray trajectory in that region, and on wave accessibility to the core. The usual estimate of the accessibility limit on the parallel index of refraction of the wave (n∥), based on a slab model, is inaccurate under these conditions, which could lead to improved antenna/wave coupling by utilizing a lower n∥. Work supported in part by US DoE under the Science Undergraduate Laboratory Internship (SULI) program and under DE-FC02-04ER54698.

  10. Apatite (U-Th)/He thermochronometry as an innovative geothermal exploration tool: A case study from the southern Wassuk Range, Nevada

    NASA Astrophysics Data System (ADS)

    Gorynski, Kyle E.; Walker, J. Douglas; Stockli, Daniel F.; Sabin, Andrew

    2014-01-01

    Extensional-type geothermal systems are complicated by the interrelation between footwall advection during exhumation, and the subsequent redistribution of heat by migrating hydrothermal fluids in the hanging wall. The southern Wassuk Range (WR) hanging wall hosts a moderate-temperature, extensional-type geothermal system and is ideal for studying this duality by analyzing a suite of apatite (AHe) and zircon (ZHe) helium samples from the footwall and hanging wall of the southern WR. Young (~ 3-4 Ma) AHe ages along the WR front are concentrated along the SE corners of segmented footwall blocks, marking the location of focused Mio-Pliocene transtension, fracture dilation, and advection. Hydrothermally reset AHe ages along the footwall range front suggest that the Hawthorne geothermal system (85°-135° C) is long lived and has resided at a prominent structural boundary in the WR footwall marked by localized advection and range-front deformation. In contrast, the presence of both hydrothermally reset and non-reset AHe ages from a ~ 1.4 km deep borehole in the hanging-wall basin probably indicate that the geothermal plumbing system and current manifestation as a thermal anomaly (~ 113 °C) are juvenile and are controlled by the generation of newly formed faults in the hanging wall. AHe ages have been shown here to greatly enhance the focusing of regional-scale geothermal exploration efforts, and for the first time have been used to identify and estimate the temperature of unseen hydrothermal fluids.

  11. Paleomagnetic study of the northern Ford Ranges, western Marie Byrd Land, West Antarctica: Motion between West and East Antarctica

    USGS Publications Warehouse

    Luyendyk, B.; Cisowski, S.; Smith, C.; Richard, S.; Kimbrough, D.

    1996-01-01

    A paleomagnetic study of Paleozoic and Mesozoic crystalline rocks in the northern Ford Ranges of Marie Byrd Land, West Antarctica, has determined a middle Cretaceous (circa 100 Ma) paleomagnetic pole and provided constraints on possible clockwise rotation of these ranges and on the rifting of east Gondwana. The 40Ar/39Ar thermochronology data from the Fosdick Mountains record a period of rapid cooling from ???700??C beginning at ???100 Ma. We relate this to extension, intrusion, and uplift associated with the beginning of rifting between Campbell Plateau and Marie Byrd Land. All rocks from the Fosdick and Chester Mountains are normally polarized. We interpret thermochronology and paleomagnetic data to infer that the region was extensively remagnetized in middle Cretaceous time. Inclinations in samples from the Chester Mountains are less steep than those from the Fosdick Mountains, which we interpret as ???25?? of south tilting of the Chesters. We interpret cooling age data for the time of magnetization to infer that the tilting began after 105 Ma and ended prior to 103 Ma. We further interpret this as constraining the beginning of extension between the Campbell Plateau and western Marie Byrd Land to the interval 105 to 103 Ma. Virtual geomagnetic poles from samples of Early Carboniferous age granodiorite from the western Phillips Mountains lie on the late Paleozoic apparent polar wander path for Australia transferred to Antarctica. Directions from 29 sites in the central and eastern Phillips and Fosdick Mountains give a Middle Cretaceous paleomagnetic pole at 222.3?? E, 70.5?? S (A95 6.1??, KAPPA 20.0). This pole is indistinguishable from other Middle Cretaceous poles for studies further east in Marie Byrd Land. Combining middle Cretaceous poles determined for three other studies of the Antarctic Peninsula. Thurston Island, and the Ruppert-Hobbs coasts with ours gives a Pacific West Antarctic pole at 215.2?? E, 73.5?? S (A95 4.0??, KAPPA 528.9). This pole is

  12. The studying of washing of arsenic and sulfur from coals having different ranges of arsenic contents

    SciTech Connect

    Mingshi Wang; Dangyu Song; Baoshan Zheng; R.B. Finkelman

    2008-10-15

    To study the effectiveness of washing in removal of arsenic and sulfur from coals with different ranges of arsenic concentration, coal was divided into three groups on the basis of arsenic content: 0-5.5 mg/kg, 5.5 mg/kg-8.00 mg/kg, and over 8.00 mg/kg. The result shows that the arsenic in coals with higher arsenic content occurs mainly in an inorganic state and can be relatively easily removed. Arsenic removal is very difficult and less complete when the arsenic content is lower than 5.5 mg/kg because most of this arsenic is in an organic state. There is no relationship between washing rate of total sulfur and arsenic content, but the relationship between the washing rate of total sulfur and percent of organic sulfur is very strong.

  13. Numerical study of the dynamics of some long range spin glass models

    NASA Astrophysics Data System (ADS)

    Billoire, Alain

    2015-07-01

    We present results of a Monte Carlo study of the equilibrium dynamics of the one dimensional long-range Ising spin glass model. By tuning a parameter σ , this model interpolates between the mean field Sherrington-Kirkpatrick model and a proxy of the finite dimensional Edward-Anderson model. Activated scaling fits for the behavior of the relaxation time τ as a function of the number of spins N (Namely \\ln (τ )\\propto {{N}\\psi} ) give values of \\psi that are not stable against inclusion of subleading corrections. Critical scaling (τ \\propto {{N}ρ} ) gives more stable fits, at least in the non mean field region. We also present results on the scaling of the time decay of the critical remanent magnetization of the Sherrington-Kirkpatrick model, a case where the simulation can be done with quite large systems and that shows the difficulties in obtaining precise values for dynamical exponents in spin glass models.

  14. The studying of washing of arsenic and sulfur from coals having different ranges of arsenic contents

    USGS Publications Warehouse

    Wang, M.; Song, D.; Zheng, B.; Finkelman, R.B.; ,

    2008-01-01

    To study the effectiveness of washing in removal of arsenic and sulfur from coals with different ranges of arsenic concentration, coal was divided into three groups on the basis of arsenic content: 0-5.5 mg/kg, 5.5 mg/kg-8.00 mg/kg, and over 8.00 mg/kg. The result shows that the arsenic in coals with higher arsenic content occurs mainly in an inorganic state and can be relatively easily removed. Arsenic removal is very difficult and less complete when the arsenic content is lower than 5.5 mg/kg because most of this arsenic is in an organic state. There is no relationship between washing rate of total sulfur and arsenic content, but the relationship between the washing rate of total sulfur and percent of organic sulfur is very strong. ?? 2008 New York Academy of Sciences.

  15. Recognition of Psychiatric Disorders, and Self-Perceived Problems. A Follow-up Study from Age 8 to Age 18

    ERIC Educational Resources Information Center

    Sourander, Andre; Haavisto, Antti; Ronning, John A.; Multimaki, Petteri; Parkkola, Kai; Santalahti, Paivi; Nikolakaros, Georgios; Helenius, Hans; Moilanen, Irma; Tamminen, Tuula; Piha, Jorma; Kumpulainen, Kirsti; Almqvist, Fredrik

    2005-01-01

    Objective: To study the rate of, and factors associated with, recognition of psychiatric disorders and self-perceived problems among 18-year-old adolescent boys. Method: The study population consisted of 2347 Finnish boys born during 1981 attending military call-up (79.7% of the original sample). At age 8, the boys were evaluated by parental and…

  16. Theoretical Study of Radiation from a Broad Range of Impurity Ions for Magnetic Fusion Diagnostics

    SciTech Connect

    Safronova, Alla

    2014-03-14

    Spectroscopy of radiation emitted by impurities plays an important role in the study of magnetically confined fusion plasmas. The measurements of these impurities are crucial for the control of the general machine conditions, for the monitoring of the impurity levels, and for the detection of various possible fault conditions. Low-Z impurities, typically present in concentrations of 1%, are lithium, beryllium, boron, carbon, and oxygen. Some of the common medium-Z impurities are metals such as iron, nickel, and copper, and high-Z impurities, such as tungsten, are present in smaller concentrations of 0.1% or less. Despite the relatively small concentration numbers, the aforementioned impurities might make a substantial contribution to radiated power, and also influence both plasma conditions and instruments. A detailed theoretical study of line radiation from impurities that covers a very broad spectral range from less than 1 Å to more than 1000 Å has been accomplished and the results were applied to the LLNL Electron Beam Ion Trap (EBIT) and the Sustained Spheromak Physics Experiment (SSPX) and to the National Spherical Torus Experiment (NSTX) at Princeton. Though low- and medium-Z impurities were also studied, the main emphasis was made on the comprehensive theoretical study of radiation from tungsten using different state-of-the-art atomic structure codes such as Relativistic Many-Body Perturbation Theory (RMBPT). The important component of this research was a comparison of the results from the RMBPT code with other codes such as the Multiconfigurational Hartree–Fock developed by Cowan (COWAN code) and the Multiconfiguration Relativistic Hebrew University Lawrence Atomic Code (HULLAC code), and estimation of accuracy of calculations. We also have studied dielectronic recombination, an important recombination process for fusion plasma, for variety of highly and low charged tungsten ions using COWAN and HULLAC codes. Accurate DR rate coefficients are needed for

  17. Physical maturation, life-history classes and age estimates of free-ranging western gorillas--insights from Mbeli Bai, Republic of Congo.

    PubMed

    Breuer, Thomas; Hockemba, Mireille Breuer-Ndoundou; Olejniczak, Claudia; Parnell, Richard J; Stokes, Emma J

    2009-02-01

    Physical maturation and life-history parameters are seen as evolutionary adaptations to different ecological and social conditions. Comparison of life-history patterns of closely related species living in diverse environments helps to evaluate the validity of these assumptions but empirical data are lacking. The two gorilla species exhibit substantial differences in their environment, which allows investigation into the role of increased frugivory in shaping western gorilla life histories. We present behavioral and morphological data on western gorilla physical maturation and life-history parameters from a 12.5-year study at Mbeli Bai, a forest clearing in the Nouabalé-Ndoki National Park in northern Congo. We assign photographs of known individuals to different life-history classes and propose new age boundaries for life-history classes in western gorillas, which can be used and tested at other western gorilla research sites. Our results show that western gorillas are weaned at a later age compared with mountain gorillas and indicate slower physical maturation of immatures. These findings support the risk-aversion hypothesis for more frugivorous species. However, our methods need to be applied and tested with other gorilla populations. The slow life histories of western gorillas could have major consequences for social structure, mortality patterns and population growth rates that will affect recovery from population crashes of this critically endangered species. We emphasize that long-term studies can provide crucial demographic and life-history data that improve our understanding of life-history evolution and adaptation and help to refine conservation strategies.

  18. Lutein intake at the age of 1 year and cardiometabolic health at the age of 6 years: the Generation R Study.

    PubMed

    Leermakers, Elisabeth T M; Kiefte-de Jong, Jessica C; Hofman, Albert; Jaddoe, Vincent W V; Franco, Oscar H

    2015-09-28

    Lutein is a carotenoid with strong antioxidant properties. Previous studies in adults suggest a beneficial role of lutein on cardiometabolic health. However, it is unknown whether this relation also exists in children; therefore, we aimed to assess the relation between lutein intake at 13 months of age and cardiometabolic outcomes at the age of 6 years. We included 2044 Dutch children participating in a population-based prospective cohort study. Diet was measured at 13 months of age with an FFQ. Lutein intake was standardised for energy and β-carotene intake. Blood pressure, anthropometrics, serum lipids and insulin were measured at the age of 6 years. Dual-energy X-ray absorptiometry was performed to measure total and regional fat and lean mass. A continuous cardiometabolic risk factor score was created, including the components body fat percentage, blood pressure, insulin, HDL-cholesterol and TAG. Age- and sex-specific standard deviation scores were created for all outcomes. Multivariable linear regression was performed, including socio-demographic and lifestyle variables. Median (energy-standardised) lutein intake was 1317 mcg/d (95% range 87, 6069 mcg/d). There were no consistent associations between lutein intake at 13 months and anthropometrics and body composition measures at 6 years of age. In addition, lutein intake was not associated with a continuous cardiometabolic risk factor score, nor was it associated with any of the individual components of the cardiometabolic risk factor score. Results from this large population-based prospective cohort study do not support the hypothesis that lutein intake early in life has a beneficial role for later cardiometabolic health.

  19. Field studies of the leachability of aged brown coal ash.

    PubMed

    Mudd, G M; Kodikara, J

    2000-09-15

    The environmental management of ash produced from the brown coal power stations of the Latrobe Valley region of Australia has been studied. Current practice consists of slurrying fly and bottom ash, a short distance to an ash disposal pond. However, storage facilities are approaching capacity and alternative ash management strategies are required in the near future. Initially, the ash produced within the power stations is known to possess a large soluble mass, which can leach rapidly to generate a saline leachate with minor trace metal content. After slurrying and deposition within the ash pond, it has been demonstrated that the soluble mass is significantly lower and the ash can be considered as aged or "leached" ash - a more benign waste that meets the criteria for fill material. In order to assess the long-term behaviour of the leached ash and its suitability for co-disposal in engineered sites within overburden dumps, two field cells were constructed and monitored over a period of 1 year. Each cell was 5 x 5 m in area, 3-m deep and HDPE lined with a coarse drainage layer and leachate collection pipe. The first cell only collected natural rainfall and was known as the Dry Cell. The second cell had an external tank of 5000 l installed (200-mm rainfall equivalent) and water was spray-irrigated regularly to simulate higher rainfall and accelerate the leaching process. The cumulative inflow and outflow for each cell has been calculated using a linear relationship and the leachate quality was monitored over time. The results demonstrate that the ash behaves as an unsaturated porous material, with the effect of evaporation through the profile being dominant and controlling the production of leachate. The leachate quality was initially moderately saline in both cells, with the concentration dropping by nearly 95% in the Wet Cell by the end of the field study. The leachate chemistry has been analysed using the PHREEQC geochemical model. The log activity plots of various

  20. The petrology, geochemistry, and age of lunar regolith breccias Miller Range 090036 and 090070: Insights into the crustal history of the Moon

    NASA Astrophysics Data System (ADS)

    Calzada-Diaz, A.; Joy, K. H.; Crawford, I. A.; Strekopytov, S.

    2017-01-01

    Meteorites ejected from the surface of the Moon as a result of impact events are an important source of lunar material in addition to Apollo and Luna samples. Here, we report bulk element composition, mineral chemistry, age, and petrography of Miller Range (MIL) 090036 and 090070 lunar meteorites. MIL 090036 and 090070 are both anorthositic regolith breccias consisting of mineral fragments and lithic clasts in a glassy matrix. They are not paired and represent sampling of two distinct regions of the lunar crust that have protoliths similar to ferroan anorthosites. 40Ar-39Ar chronology performed on two subsplits of MIL 090070,33 (a pale clast impact melt and a dark glassy melt component) shows that the sample underwent two main degassing events, one at 3.88 Ga and another at 3.65 Ga. The cosmic ray exposure data obtained from MIL 090070 are consistent with a short ( 8-9 Ma) exposure close to the lunar surface. Bulk-rock FeO, TiO2, and Th concentrations in both samples were compared with 2-degree Lunar Prospector Gamma Ray Spectrometer (LP-GRS) data sets to determine areas of the lunar surface where the regolith matches the abundances observed on the sample. We find that MIL 090036 bulk rock is compositionally most similar to regolith surrounding the Procellarum KREEP Terrane, whereas MIL 090070 best matches regolith in the feldspathic highlands terrane on the lunar farside. Our results suggest that some areas of the lunar farside crust are composed of ferroan anorthosite, and that the samples shed light on the evolution and impact bombardment history of the ancient lunar highlands.

  1. Age and composition of Archean crystalline rocks from the southern Madison Range, Montana. Implications for crustal evolution in the Wyoming craton

    SciTech Connect

    Mueller, P.A.; Shuster, R.D. ); Wooden, J.L. ); Erslev, E.A. ); Bowes, D.R. )

    1993-04-01

    The southern Madison Range of southwestern Montana contains two distinct Precambrian lithologic assemblages: (1) a complex of tonalitic to granitic gneisses that has been thrust over (2) a medium-grade metasupracrustal sequence dominated by pelitic schist. Crystallization ages for the protolith of a granodioritic gneiss that intruded the metasupracrustal sequence ([approximately]2.6 Ga)-along with an intercalated meta-andesite ([approximately]2.7 Ga) confirm the sequence as Archean. Chemical (major and trace element), isotopic (Rb-Sr, Sm-Nd, Pb-Pb), and geochronologic (U-Pb zircon) data for selected components of the gneiss complex indicate two groups of gneisses: an older, tonalitic to trondhjemitic group ([approximately]3.3 Ga) and a younger, mostly granitic group ([approximately]2.7 Ga). Both groups of gneisses exhibit the radiogenic Pb and nonradiogenic Nd isotopic signature characteristic of Middle and Late Archean rocks from throughout the Wyoming province. The older gneisses, in particular, appear to be compositionally, isotopically, and chronologically comparable to other Middle Archean gneisses from the northern part of the province (for example, Beartooth Mountains). The Late Archean gneisses, however, exhibit some distinct differences relative to their temporal counterparts, including (1) trace-element patterns that are more suggestive of crustal melts than subduction activity and (2) higher initial Sr isotopic ratios that suggest more involvement of older crust in their petrogenesis. These comparisons suggest that the juxtaposition of Late Archean terranes in the northern Wyoming province was the result, at least in part, of intracratonic processes. 41 refs., 6 figs., 2 tabs.

  2. Reddening and age of six poorly studied star clusters of the Large Magellanic Cloud derived from integrated spectra

    NASA Astrophysics Data System (ADS)

    Minniti, J. H.; Ahumada, A. V.; Clariá, J. J.; Benítez-Llambay, A.

    2014-05-01

    Aims: To increase the number of studied star clusters (SCs) of the Large Magellanic Cloud (LMC), we present flux-calibrated integrated spectra in the optical range (λ = 3700-6800 Å) for six poorly studied LMC SCs of IVA type. This type corresponds to the age range between 200 and 400 Myr. We also aim at creating a new template spectrum representative of this age range at the metallicity level of the LMC. Methods: Foreground reddening E(B - V) values and ages are derived by applying the template matching method that consists of comparing the line strengths and continuum distribution of the cluster spectra with those of template cluster spectra with known properties. The equivalent width (EW) of the Balmer lines and the diagnostic diagrams involving the sum of EWs of selected spectral lines were also employed as age indicators. Results: For the first time, we provide estimates of the clusters' reddenings and ages. As expected, all the clusters appear to be of nearly the same age, their mean value being (400 ± 100) Myr, while the resulting mean E(B - V) values range between 0.00 and 0.10 mag. Conclusions: The present cluster sample complements previous ones in an effort to gather a spectral library with several clusters per age bin. By averaging the reddening-corrected integrated spectra, weighted by their signal-to-noise ratios (S/N), a new high S/N template spectrum of 400 Myr has been created. Integrated spectra for each star cluster are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/565/A49

  3. Impact of biological aging on arterial aging in American Indians: findings from the Strong Heart Family Study

    PubMed Central

    Peng, Hao; Zhu, Yun; Yeh, Fawn; Cole, Shelley A.; Best, Lyle G.; Lin, Jue; Blackburn, Elizabeth; Devereux, Richard B.; Roman, Mary J.; Lee, Elisa T.; Howard, Barbara V.; Zhao, Jinying

    2016-01-01

    Telomere length, a marker of biological aging, has been associated with cardiovascular disease (CVD). Increased arterial stiffness, an indicator of arterial aging, predicts adverse CVD outcomes. However, the relationship between telomere length and arterial stiffness is less well studied. Here we examined the cross-sectional association between leukocyte telomere length (LTL) and arterial stiffness in 2,165 American Indians in the Strong Heart Family Study (SHFS). LTL was measured by qPCR. Arterial stiffness was assessed by stiffness index β. The association between LTL and arterial stiffness was assessed by generalized estimating equation model, adjusting for sociodemographics (age, sex, education level), study site, metabolic factors (fasting glucose, lipids, systolic blood pressure, and kidney function), lifestyle (BMI, smoking, drinking, and physical activity), and prevalent CVD. Results showed that longer LTL was significantly associated with a decreased arterial stiffness (β=-0.070, P=0.007). This association did not attenuate after further adjustment for hsCRP (β=-0.071, P=0.005) or excluding participants with overt CVD (β=-0.068, P=0.012), diabetes (β=-0.070, P=0.005), or chronic kidney disease (β=-0.090, P=0.001). In summary, shorter LTL was significantly associated with an increased arterial stiffness, independent of known risk factors. This finding may shed light on the potential role of biological aging in arterial aging in American Indians. PMID:27540694

  4. Genetic effect on blood pressure is modulated by age: the Hypertension Genetic Epidemiology Network Study.

    PubMed

    Shi, Gang; Gu, Chi C; Kraja, Aldi T; Arnett, Donna K; Myers, Richard H; Pankow, James S; Hunt, Steven C; Rao, Dabeeru C

    2009-01-01

    Genome-wide linkage analysis was performed for systolic and diastolic blood pressures in the Hypertension Genetic Epidemiology Network. We investigated the role of gene-age interactions using a recently developed variance components method that incorporates age variation in genetic effects. Substantially improved linkage evidence, in terms of both the number of linkage peaks and their significance levels, was observed. Twenty-six linkage peaks were identified with maximum logarithm of odds scores ranging between 3.0 and 4.6, 15 of which were cross-validated by the literature. The chromosomal region 1p36 that showed the highest logarithm of odds score in our study was found to be supported by evidence from 3 studies. The new method also led to vastly improved validation across ethnic groups. Ten of the 15 supported linkage peaks were cross-validated between 2 different ethnic groups, and 2 peaks on chromosomal region 1q31 and 16p11 were validated in 3 ethnic groups. In conclusion, this investigation demonstrates that genetic effects on blood pressure vary by age. The improved genetic linkage results presented here should help to identify the specific genetic variants that explain the observed results.

  5. Small-scale studies of roasted ore waste reveal extreme ranges of stable mercury isotope signatures

    NASA Astrophysics Data System (ADS)

    Smith, Robin S.; Wiederhold, Jan G.; Jew, Adam D.; Brown, Gordon E.; Bourdon, Bernard; Kretzschmar, Ruben

    2014-07-01

    Active and closed Hg mines are significant sources of Hg contamination to the environment, mainly due to large volumes of mine waste material disposed of on-site. The application of Hg isotopes as source tracer from such contaminated sites requires knowledge of the Hg isotope signatures of different materials potentially released to the environment. Previous work has shown that calcine, the waste residue of the on-site ore roasting process, can exhibit distinct Hg isotope signatures compared with the primary ore. Here, we report results from a detailed small-scale study of Hg isotope variations in calcine collected from the closed New Idria Hg mine, San Benito County, CA, USA. The calcine samples exhibited different internal layering features which were investigated using optical microscopy, micro X-ray fluorescence, micro X-ray absorption spectroscopy (μ-XAS), and stable Hg isotope analysis. Significant Fe, S, and Hg concentration gradients were found across the different internal layers. Isotopic analyses revealed an extreme variation with pronounced isotopic gradients across the internal layered features. Overall, δ202Hg (±0.10‰, 2 SD) describing mass-dependent fractionation (MDF) ranged from -5.96 to 14.49‰, which is by far the largest range of δ202Hg values reported for any environmental sample. In addition, Δ199Hg (±0.06‰, 2 SD) describing mass-independent fractionation (MIF) ranged from -0.17 to 0.21‰. The μ-XAS analyses suggested that cinnabar and metacinnabar are the dominant Hg-bearing phases in the calcine. Our results demonstrate that the incomplete roasting of HgS ores in Hg mines can cause extreme mass-dependent Hg isotope fractionations at the scale of individual calcine pieces with enrichments in both light and heavy Hg isotopes relative to the primary ore signatures. This finding has important implications for the application of Hg isotopes as potential source tracers for Hg released to the environment from closed Hg mines and

  6. Elementary school-aged children's reports of their health: a cognitive interviewing study.

    PubMed

    Rebok, G; Riley, A; Forrest, C; Starfield, B; Green, B; Robertson, J; Tambor, E

    2001-01-01

    There are no standard methods for assessing the quality of young children's perceptions of their health and well-being and their ability to comprehend the tasks involved in reporting their health. This research involved three cross-sectional studies using cognitive interviews of 5-11-year-old children (N = 114) to determine their ability to respond to various presentations of pictorially illustrated questions about their health. The samples had a predominance of children in the 5-7-year-old range and families of lower and middle socio-economic status. The research questions in Study 1 involved children's ability to convert their health experiences into scaled responses and relate them to illustrated items (n = 35); Study 2 focused on the type of response format most effectively used by children (n = 19); and Study 3 involved testing children's understanding of health-related terms and use of a specific recall period (n = 60). The results of Study 1 showed that children identified with the cartoon drawing of a child depicted in the illustrated items, typically responding that the child was at or near their own age and of the same gender, with no differences related to race. Study 2 results indicated that children responded effectively to circles of graduated sizes to indicate their response and preferred them to same-size circles or a visual analogue scale. Tests of three-, four-, and five-point response formats demonstrated that children could use them all without confusion. In Study 3, expected age-related differences in understanding were obtained. In fact, the 5-year-old children were unable to understand a sufficient number of items to adequately describe their health. Virtually all children 8 years of age and older were able to fully understand the key terms and presentation of items, used the full five-point range of response options, and accurately used a 4-week recall period. Six- and seven-year-olds were more likely than older children to use only the

  7. Relationship Between Wealth and Age Trajectories of Walking Speed Among Older Adults: Evidence From the English Longitudinal Study of Ageing

    PubMed Central

    2013-01-01

    Background. Slow walking speed is associated with higher risk of accidents, disability, and mortality in older adults, with people in more disadvantaged socioeconomic positions being at higher risk. We explore the relationship between wealth and age trajectories of walking speed among older adults. Methods. Data come from three waves (2002–2003 to 2006–2007) of the English Longitudinal Study of Ageing. We use latent growth curve models and aging-vector graphs to explore individual changes and average population age trajectories of walking speed by wealth among 7,225 individuals aged 60 and older. Results. For someone aged 71 in the poorest wealth quintile, the baseline mean walking speed was 0.75 m/s, which decreased to 0.71 m/s 4 years later, whereas that of a person in the richest wealth quintile was 0.91 m/s, which decreased to 0.82 m/s. Although the decline in walking speed was faster among people in the richest wealth (net of covariates), the gaps in walking speed between richest and poorest did not close. Even after accounting for covariates, people in the richest wealth only reached critical values (0.60 m/s) of walking speed at the age of 90, whereas people in the poorest wealth reached that level 6 years earlier. Conclusions. Our findings showed continuing gaps in physical functioning by wealth, even among people with the same health, psychosocial, and demographic conditions. As wealth reflects both past and current socioeconomic status, the implications of our findings are that reducing socioeconomic inequalities at all stages of the life course may have a positive impact on functioning in old age. PMID:23682157

  8. “IDEAL” Aging is Associated with Lower Resting Metabolic Rate: The Baltimore Longitudinal Study of Aging

    PubMed Central

    Schrack, Jennifer A.; Knuth, Nicolas D.; Simonsick, Eleanor M.; Ferrucci, Luigi

    2014-01-01

    Objectives To assess the associations among age, health status, and resting metabolic rate (RMR) in a large population of older adults. Design Cross-Sectional Analysis Setting Community-dwelling volunteers from the Baltimore Longitudinal Study of Aging (BLSA) Participants Four hundred twenty persons aged 40 – 96 (mean 68.2 ± 11.0) who underwent a comprehensive physical examination, cognitive assessment, resting metabolic rate testing, body composition assessment, and physical function testing during a three-day clinic visit. Measurements Participants were assigned to “IDEAL” (Insight into the Determination of Exceptional Aging and Longevity) or “non-IDEAL” categories based on health status. IDEAL participants were defined by the absence of: physical and cognitive impairments, chronic conditions/comorbidities and blood profile alterations. A three-stage linear regression model was used to assess the relationship between RMR and age, using IDEAL classification as a predictor, adjusting for sex and body composition. Results RMR averaged 1512.4 (± 442.9) kcal/day and was lower with advancing age (β = −8.55, p < 0.001). After adjusting for age, sex, and body composition RMR was 109.6 kcals/day lower in IDEAL than non-IDEAL participants (p < 0.005). Conclusions Individuals who are fully functional and free of major medical conditions have lower RMR than those affected by disease and functional impairments. These findings suggest that health status plays a role in energy utilization and regulation independent of age and body composition and that elevated RMR may be a global biomarker of poor health in older persons. PMID:24635835

  9. Organic tanks safety program FY96 waste aging studies

    SciTech Connect

    Camaioni, D.M.; Samuels, W.D.; Linehan, J.C.; Clauss, S.A.; Sharma, A.K.; Wahl, K.L.; Campbell, J.A.

    1996-10-01

    Uranium and plutonium production at the Hanford Site produced large quantities of radioactive by-products and contaminated process chemicals, which are stored in underground tanks awaiting treatment and disposal. Having been made strongly alkaline and then subjected to successive water evaporation campaigns to increase storage capacity, the wastes now exist in the physical forms of salt cakes, metal oxide sludges, and partially saturated aqueous brine solutions. The tanks that contain organic process chemicals mixed with nitrate/nitrite salt wastes may be at risk for fuel- nitrate combustion accidents. The purpose of the Waste Aging Task is to elucidate how chemical and radiological processes will have aged or degraded the organic compounds stored in the tanks. Ultimately, the task seeks to develop quantitative measures of how aging changes the energetic properties of the wastes. This information will directly support efforts to evaluate the hazard as well as to develop potential control and mitigation strategies.

  10. Paleointensity study on obsidians of Pleistocene Age from Armenia

    NASA Astrophysics Data System (ADS)

    Frank, Sandra; Ferk, Annika; Kirscher, Uwe; Leonhardt, Roman; Meliksetian, Khachatur; Hess, Kai-Uwe; Dingwell, Donald; Bachtadse, Valerian

    2014-05-01

    Volcanic glass is often considered an ideal recording material for paleointensities. Experiments to determine the ancient field intensity are time consuming and mostly have low success rates. Studies have shown that the usage of glassy samples can increase success rates very much as the remanence carriers are in or close to the single domain range. However, it was found that hydration and/or devitrification may falsify the results and maybe hard to identify. Here we investigate up to ~6 myr old subaerial obsidians of rhyolitic composition from Armenia to examine time dependencies in such processes and to obtain high quality field records. We present data from 60 subaerial obsidian samples from nine volcanic structures of Armenia. Almost all samples show a linear directional component which trends towards the origin of projection in both thermal and alternating field demagnetization experiments. The 1.75 and ~6myr old glasses are inversely magnetized while all other samples show normal polarity. Titanomagnetites with varying titanium content and Curie temperatures at 190 to 270°C and 530° to 570°C, respectively, were revealed to be the remanence carriers. Almost all thermomagnetic curves are reversible underlining the thermal stability of the material. Thellier-type experiments with alteration and tail checks were used to determine paleointensities. Virtual axial dipole moments of 4.6*1022 Am2 (0.5Ma), 8.6*1022 Am2 (0.65Ma), 9.4*1022 Am2 (1.5Ma), 6.9*1022 Am2 and 7.3*1022 Am2 (~6 Ma) were found which agrees well with published reference data (Channell et al., 2009). The thermal stability, low alteration and good accordance with other data support the suitability of glassy materials for geomagnetic field studies and also shows the potential of subaerial obsidian to identify the source areas of prehistoric obsidian artefacts.

  11. Use of cosmogenic 35S for comparing ages of water from three alpine-subalpine basins in the Colorado Front Range

    USGS Publications Warehouse

    Sueker, J.K.; Turk, J.T.; Michel, R.L.

    1999-01-01

    High-elevation basins in Colorado are a major source of water for the central and western United States; however, acidic deposition may affect the quality of this water. Water that is retained in a basin for a longer period of time may be less impacted by acidic deposition. Sulfur-35 (35S), a short-lived isotope of sulfur (t( 1/2 ) = 87 days), is useful for studying short-time scale hydrologic processes in basins where biological influences and water/rock interactions are minimal. When sulfate response in a basin is conservative, the age of water may be assumed to be that of the dissolved sulfate in it. Three alpine-subalpine basins on granitic terrain in Colorado were investigated to determine the influence of basin morphology on the residence time of water in the basins. Fern and Spruce Creek basins are glaciated and accumulate deep snowpacks during the winter. These basins have hydrologic and chemical characteristics typical of systems with rapid hydrologic response times. The age of sulfate leaving these basins, determined from the activity of 35S, averages around 200 days. In contrast, Boulder Brook basin has broad, gentle slopes and an extensive cover of surficial debris. Its area above treeline, about one-half of the basin, is blown free of snow during the winter. Variations in flow and solute concentrations in Boulder Brook are quite small compared to Fern and Spruce Creeks. After peak snowmelt, sulfate in Boulder Brook is about 200 days older than sulfate in Fern and Spruce Creeks. This indicates a substantial source of older sulfate (lacking 35S) that is probably provided from water stored in pore spaces of surficial debris in Boulder Brook basin.

  12. Propulsion system studies for an advanced high subsonic, long range jet commercial transport aircraft

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Propulsion system characteristics for a long range, high subsonic (Mach 0.90 - 0.98), jet commercial transport aircraft are studied to identify the most desirable cycle and engine configuration and to assess the payoff of advanced engine technologies applicable to the time frame of the late 1970s to the mid 1980s. An engine parametric study phase examines major cycle trends on the basis of aircraft economics. This is followed by the preliminary design of two advanced mixed exhaust turbofan engines pointed at two different technology levels (1970 and 1985 commercial certification for engines No. 1 and No. 2, respectively). The economic penalties of environmental constraints - noise and exhaust emissions - are assessed. The highest specific thrust engine (lowest bypass ratio for a given core technology) achievable with a single-stage fan yields the best economics for a Mach 0.95 - 0.98 aircraft and can meet the noise objectives specified, but with significant economic penalties. Advanced technologies which would allow high temperature and cycle pressure ratios to be used effectively are shown to provide significant improvement in mission performance which can partially offset the economic penalties incurred to meet lower noise goals. Advanced technology needs are identified; and, in particular, the initiation of an integrated fan and inlet aero/acoustic program is recommended.

  13. FTIR study of carbonate loss from carbonated apatites in the wide temperature range.

    PubMed

    Rau, J V; Cesaro, S Nunziante; Ferro, D; Barinov, S M; Fadeeva, I V

    2004-11-15

    The mineral constituent of bone tissue is a carbonate-substituted apatite (CHA). The thermal stability of the CHA has been revealed to depend on the substitution type and degree, although relatively little is known about this behavior. The aim of this study was to investigate the carbonate loss from synthetic CHAs in equilibrium conditions in a wide temperature range. An approach based on FTIR spectroscopy of condensed gas phase was applied to evaluate the CO and CO2 release with increasing temperature. Four different CHAs were studied, which were prepared by either precipitation from solution or the solid-state interaction. The samples differ from each other by the substitution degree. In one of the samples calcium was partially substituted by magnesium. Decomposition was shown to start at surprisingly low temperature, about 400 degrees C, and the CO content increases monotonously with the increase of temperature. The CO2 content goes through a maximum due to its decomposition into carbon monoxide and oxygen, the temperature of this maximum being strongly dependent on the chemical synthesis route. Therefore, control of the sintering atmosphere with respect to the CO2/CO ratio is needed when preparing the carbonated apatite bioceramics.

  14. Age, Stress, and Emotional Complexity: Results from Two Studies of Daily Experiences

    PubMed Central

    Scott, Stacey B.; Sliwinski, Martin J.; Mogle, Jacqueline A.; Almeida, David M.

    2014-01-01

    Experiencing positive and negative emotions together (i.e., co-occurrence) has been described as a marker of positive adaptation during stress and a strength of socio-emotional aging. Using data from daily diary (N=2,022; ages 33-84) and ecological momentary assessment (N=190; ages 20-80) studies, we evaluate the utility of a common operationalization of co-occurrence, the within-person correlation between positive affect (PA) and negative affect (NA). Then we test competing predictions regarding when co-occurrence will be observed and whether age differences will be present. Results indicate that the correlation is not an informative indicator of co-occurrence. Although correlations were stronger and more negative when stressors occurred (typically interpreted as lower co-occurrence), objective counts of emotion reports indicated that positive and negative emotions were more 3 to 4 times likely to co-occur when stressors were reported. This suggests that co-occurrence reflects the extent to which negative emotions intrude on typically positive emotional states, rather than the extent to which people maintain positive emotions during stress. The variances of both PA and NA increased at stressor reports, indicating that individuals reported a broader not narrower range of emotion during stress. Finally, older age was associated with less variability in NA and a lower likelihood of co-occurring positive and negative emotions. In sum, these findings cast doubt on the utility of the PA-NA correlation as an index of emotional co-occurrence, and question notion that greater emotional cooccurrence represents either a typical or adaptive emotional state in adults. PMID:25244477

  15. Laboratory studies of immersion and deposition mode ice nucleation of ozone aged mineral dust particles

    NASA Astrophysics Data System (ADS)

    Kanji, Z. A.; Welti, A.; Chou, C.; Stetzer, O.; Lohmann, U.

    2013-04-01

    Ice nucleation in the atmosphere is central to the understanding the microphysical properties of mixed-phase and cirrus clouds. Ambient conditions such as temperature (T) and relative humidity (RH), as well as aerosol properties such as chemical composition and mixing state play an important role in predicting ice formation in the troposphere. Previous field studies have reported the absence of sulphate and organic compounds on mineral dust ice crystal residuals sampled at mountain top stations or aircraft based measurements despite the long range transport mineral dust is subjected to. We present laboratory studies of ice nucleation for immersion and deposition mode on ozone aged mineral dust particles for 233 < T < 263 K that will represent ageing but not internal mixing with in(organic) compounds. Heterogeneous ice nucleation of untreated kaolinite (Ka) and Arizona Test Dust (ATD) particles is compared to corresponding aged particles that are subjected to ozone exposures of 0.4-4.3 ppmv in a stainless steel aerosol tank. The portable ice nucleation counter (PINC) and immersion chamber combined with the Zurich ice nucleation chamber (IMCA - ZINC) are used to conduct deposition and immersion mode measurements respectively. Ice active fractions as well as ice active surface site densities (ns) are reported and observed to increase as a function of temperature. We present first results that demonstrate enhancement of the ice nucleation ability of aged mineral dust particles in both the deposition and immersion mode due to ageing. Additionally, these are also the first results to show a suppression of heterogeneous ice nucleation without the condensation of a coating of (in)organic material. In immersion mode, low exposure Ka particles showed enhanced ice activity requiring a median freezing temperature of 1.5 K warmer than that of untreated Ka whereas high exposure ATD particles showed suppressed ice nucleation requiring a median freezing temperature of 3 K colder

  16. Dental arch dimensions in the mixed dentition: a study of Brazilian children from 9 to 12 years of age

    PubMed Central

    LOULY, Fabiane; NOUER, Paulo Roberto Aranha; JANSON, Guilherme; PINZAN, Arnaldo

    2011-01-01

    Objective This study evaluated dental arch dimensional changes of Brazilian children. Material and methods Dental casts were taken from 66 children (29 males; 37 females) with normal occlusion selected among 1,687 students from public and private schools aged 9, 10, 11 and 12 years, according to the following criteria: Class I canine and molar relationships; well-aligned upper and lower dental arches; mixed dentition; good facial symmetry; no previous orthodontic treatment. Dental arch dimensions were taken by one examiner using the Korkhaus’ compass and a digital pachymeter. ANOVA test was applied to compare the arch dimensions at the different ages and the t-test was used to compare the arch dimensions of male and female subjects. Arch forms were compared by means of chi-square tests. Results Only the maxillary anterior segment length showed a statistically significant increase from 10 to 12 years of age. Males had a significantly larger maxillary depth than females at the age range evaluated. The predominant dental arch form found was elliptical. Conclusion In the studied age range, anterior maxillary length increased from 10 to 12 years of age, males had larger maxillary depth than females and the predominant arch form was elliptical. PMID:21552719

  17. Age 60 Study, Part 4: Experimental Evaluation of Pilot Performance

    DTIC Science & Technology

    1994-10-01

    and aging. Computerized cognitive test batteries, COGSREEN and WOMBAT , were selected as the domain-independent measures. Flitescript and whole task...were assessed. COGSCREEN total composite scores were significantly correlated with evaluator ratings on emergency/abnormal maneuvers. Neither WOMBAT ...B-3 WOMBAT Questionnaire .......................................... B-4 Sim ulator Post-flight Questionnaire

  18. Lead Exposure and Tremor among Older Men: The VA Normative Aging Study

    PubMed Central

    Power, Melinda C.; Sparrow, David; Spiro, Avron; Hu, Howard; Louis, Elan D.; Weisskopf, Marc G.

    2015-01-01

    Background: Tremor is one of the most common neurological signs, yet its etiology is poorly understood. Case–control studies suggest an association between blood lead and essential tremor, and that this association is modified by polymorphisms in the δ-aminolevulinic acid dehydrogenase (ALAD) gene. Objective: We aimed to examine the relationship between lead and tremor, including modification by ALAD, in a prospective cohort study, using both blood lead and bone lead—a biomarker of cumulative lead exposure. Methods: We measured tibia (n = 670) and patella (n = 672) bone lead and blood lead (n = 807) among older men (age range, 50–98 years) in the VA Normative Aging Study cohort. A tremor score was created based on an approach using hand-drawing samples. ALAD genotype was dichotomized as ALAD-2 carriers or not. We used linear regression adjusted for age, education, smoking, and alcohol intake to estimate the associations between lead biomarkers and tremor score. Results: In unadjusted analyses, there was a marginal association between quintiles of all lead biomarkers and tremor scores (p-values < 0.13), which did not persist in adjusted models. Age was the strongest predictor of tremor. Among those younger than the median age (68.9 years), tremor increased significantly with blood lead (p = 0.03), but this pattern was not apparent for bone lead. We did not see modification by ALAD or an association between bone lead and change in tremor score over time. Conclusion: Our results do not strongly support an association between lead exposure and tremor, and suggest no association with cumulative lead biomarkers, although there is some suggestion that blood lead may be associated with tremor among the younger men in our cohort. Citation: Ji JS, Power MC, Sparrow D, Spiro A III, Hu H, Louis ED, Weisskopf MG. 2015. Lead exposure and tremor among older men: the VA Normative Aging Study. Environ Health Perspect 123:445–450; http://dx.doi.org/10.1289/ehp.1408535

  19. Study of the possibility of diagnostic cataract in the THz range

    NASA Astrophysics Data System (ADS)

    Ezerskaya, A.; Smolyanskaya, O.; Goncharenko, A.; Geyko, I.

    2013-03-01

    It was revealed correlation between the optical density of the lens's nucleus in terahertz range with its density, determined according to the L. Buratti classification. Consolidation of the lens fibers caused by senile cataract, increases the reflectivity of the lens in the THz range. The temporal structure of reflected THz signals allows to determine the spatial distribution of density in the lens.

  20. Monte Carlo Study of One-Dimensional Ising Models with Long-Range Interactions

    NASA Astrophysics Data System (ADS)

    Tomita, Yusuke

    2009-01-01

    Recently, Fukui and Todo have proposed a new effective Monte Carlo algorithm for long-range interacting systems. Using the algorithm with the nonequilibrium relaxation method, we investigated long-range interacting one-dimensional Ising models both ferromagnetic and antiferromagnetic with the nearest-neighbor ferromagnetic interaction. For the antiferromagnetic model, we found the systems are paramagnetic at finite temperatures.

  1. Accuracy of Range Restriction Correction with Multiple Imputation in Small and Moderate Samples: A Simulation Study

    ERIC Educational Resources Information Center

    Pfaffel, Andreas; Spiel, Christiane

    2016-01-01

    Approaches to correcting correlation coefficients for range restriction have been developed under the framework of large sample theory. The accuracy of missing data techniques for correcting correlation coefficients for range restriction has thus far only been investigated with relatively large samples. However, researchers and evaluators are…

  2. Budding yeast as a model organism to study the effects of age.

    PubMed

    Denoth Lippuner, Annina; Julou, Thomas; Barral, Yves

    2014-03-01

    Although a budding yeast culture can be propagated eternally, individual yeast cells age and eventually die. The detailed knowledge of this unicellular eukaryotic species as well as the powerful tools developed to study its physiology makes budding yeast an ideal model organism to study the mechanisms involved in aging. Considering both detrimental and positive aspects of age, we review changes occurring during aging both at the whole-cell level and at the intracellular level. The possible mechanisms allowing old cells to produce rejuvenated progeny are described in terms of accumulation and inheritance of aging factors. Based on the dynamic changes associated with age, we distinguish different stages of age: early age, during which changes do not impair cell growth; intermediate age, during which aging factors start to accumulate; and late age, which corresponds to the last divisions before death. For each aging factor, we examine its asymmetric segregation and whether it plays a causal role in aging. Using the example of caloric restriction, we describe how the aging process can be modulated at different levels and how changes in different organelles might interplay with each other. Finally, we discuss the beneficial aspects that might be associated with age.

  3. Girls' Stable Peer Status and Their Adulthood Adjustment: A Longitudinal Study from Age 10 to Age 43

    ERIC Educational Resources Information Center

    Zettergren, Peter; Bergman, Lars R.; Wangby, Margit

    2006-01-01

    Stable peer status clusters of rejected, popular, and average girls from ages 10 to 13 were identified and associated to young and middle adulthood adjustment. The study included a representative sample of 445 females from the longitudinal research program Individual Development and Adaptation. Results showed that, by young adulthood, rejected…

  4. Studying biological membranes with extended range high-speed atomic force microscopy

    PubMed Central

    Nievergelt, Adrian P.; Erickson, Blake W.; Hosseini, Nahid; Adams, Jonathan D.; Fantner, Georg E.

    2015-01-01

    High—speed atomic force microscopy has proven to be a valuable tool for the study of biomolecular systems at the nanoscale. Expanding its application to larger biological specimens such as membranes or cells has, however, proven difficult, often requiring fundamental changes in the AFM instrument. Here we show a way to utilize conventional AFM instrumentation with minor alterations to perform high-speed AFM imaging with a large scan range. Using a two—actuator design with adapted control systems, a 130 × 130 × 5 μm scanner with nearly 100 kHz open—loop small-signal Z—bandwidth is implemented. This allows for high-speed imaging of biologically relevant samples as well as high-speed measurements of nanomechanical surface properties. We demonstrate the system performance by real-time imaging of the effect of charged polymer nanoparticles on the integrity of lipid membranes at high imaging speeds and peak force tapping measurements at 32 kHz peak force rate. PMID:26169348

  5. Application of close-range aerial infrared thermography to detect landfill gas emissions: a case study

    NASA Astrophysics Data System (ADS)

    Tanda, G.; Migliazzi, M.; Chiarabini, V.; Cinquetti, P.

    2017-01-01

    Monitoring waste disposal sites is important to check that the produced biogas, potentially explosive, is properly collected by the biogas extraction system of the landfill site and to evaluate the residual biogas flow escaping from upper surface of the landfill. As the biogas migrates to the surface, the soil through which it flows is expected to reach a higher temperature than the surrounding environment; thus, measuring the thermal footprint of the landfill soil surface could allow the detection of biogas leakages and spots suitable for the gas extraction. Close-range aerial infrared thermography is an innovative approach able to identify thermal anomalies with a good resolution over a large region of the landfill surface. A simple procedure to deduce the biogas flow rate emerging from the soil into the atmosphere, based on infrared thermography measurements, is presented. The approach has been applied to a case study concerning a large landfill located in Genoa (Italy). Aerial infrared photographs taken during different days and seasons showed the presence of thermal anomalies over regions along the peripheral boundary of the landfill still not interested in biogas extraction.

  6. Medicanes: A prognostic analysis of November 7, 2014, case study based on ECMWF medium range products

    NASA Astrophysics Data System (ADS)

    Matsangouras, Ioannis; Nastos, Panagiotis; Pytharouris, Ioannis; Kamperakis, Nicolaos

    2015-04-01

    Mediterranean basin is a well-known European region for cyclone formation. The so-called medicanes (MEDIterranean hurriCANES) are cyclones that develop over the Mediterranean basin and exhibit some similarities to tropical cyclones. These rare meteorological phenomena are rare warm-core cyclones that may cause significant impact at coastal regions. In this paper, we present an analysis of prognostic products derived from the European Centre for Medium-Range Weather Forecasts (ECMWF) investigating the development of a medicane case study. All forecast products are based on the 12:00 UTC ECMWF run. On November 7, 2014, a medicane developed over central Mediterranean, first hitting Lampedusa on the island of Linosa, then Malta (at around 16.30 UTC), and finally the eastern coast of Sicily. The analysis revealed that ECMWF 240 forecast products highlighted the central Mediterranean basin as an area of deep cyclonic circulation. In addition, results from 240 to 24 forecast analysis, demonstrated that this cyclonic signature became more constant.

  7. Intensive vs. free-range organic beef. A preference study through consumer liking and conjoint analysis.

    PubMed

    García-Torres, S; López-Gajardo, A; Mesías, F J

    2016-04-01

    This paper evaluates consumer liking and preferences towards organic beef from two production systems allowed by EU regulation: i) free-range and ii) intensive (fattened in feed-lot with organic feedstuff) as compared with conventionally produced beef. Data were obtained in April-May 2014 with a sample of 150 regular beef consumers who completed two tasks: firstly a sensory test where consumers tasted and rated the meats and secondly a conjoint analysis to study beef purchasing preferences. Willingness-to-pay for the different meats was also calculated from conjoint results. Results show that consumers preferred organic-from-concentrate beef at sensory level while organic beef from animals fed on grass was preferred when process characteristics (i.e. farming system) or attributes perceived at the point of purchase (i.e. colour) were evaluated. It was also found that the price-premium for organic beef is over 40%, with organic-fed-on grass beef preferred slightly over that fed-on-concentrate.

  8. Study Of Short-Range Correlations With 6-9 GeV/c Protons

    SciTech Connect

    Watson, J. W.

    2008-10-13

    We studied the {sup 12}C(p,2p+n) reaction at beam momenta of 5.9, 8.0 and 9.0 GeV/c. For quasielastic (p,2p) events we reconstructed p{sub f}, the momentum of the knocked-out proton before the reaction;, p{sub f} was then compared (event-by-event) with p{sub n}, the measured, coincident neutron momentum. For |p{sub n}|>k{sub F} = 0.220 GeV/c(the Fermi momentum) a strong back-to-back directional correlation between p{sub f} and p{sub n} was observed, indicative of short-range n-p correlations. From these data we concluded that for nuclear protons with momenta >0.275 GeV/c, 92{+-}18% have correlated neutron partners. This result was recently corroborated by an experiment with 4.6 GeV electrons.

  9. Photodissociation study of ethyl bromide in the ultraviolet range by the ion-velocity imaging technique.

    PubMed

    Tang, Ying; Ji, Lei; Zhu, Rongshu; Wei, Zhengrong; Zhang, Bing

    2005-10-14

    The photodissociation of ethyl bromide has been studied in the wavelength range of 231-267 nm by means of the ion velocity imaging technique coupled with a [2+1] resonance-enhanced multiphoton ionization (REMPI) scheme. The velocity distributions for the Br ((2)P(1/2)) (denoted Br*) and Br ((2)P(3/2)) (denoted Br) fragments are determined, and each can be well-fitted by a narrow single-peaked Gaussian curve, which suggests that the bromine fragments are generated as a result of direct dissociation via repulsive potential-energy surfaces (PES). The recoil anisotropy results show that beta(Br) and beta(Br*) decrease with the wavelength, and the angular distributions of Br* suggest a typical parallel transition. The product relative quantum yields at two different wavelengths are Phi(234nm)(Br*)=0.17 and Phi(267nm)(Br*)=0.31. The relative fractions of each potential surface for the bromine fragments' production at 234 and 267 nm reveal the existence of a curve crossing between the (3)Q(0) and (1)Q(1) potential surfaces, and the probability of curve crossing decreases with the laser wavelength. The symmetry reduction of C(2)H(5)Br from C(3v) to C(s) invokes a nonadiabatic coupling between the (3)Q(0) and (1)Q(1) states, and with higher energy photons, the probability that crossing will take place increases.

  10. A dose-ranging study of tiotropium delivered via Respimat Soft Mist Inhaler or HandiHaler in COPD patients.

    PubMed

    Caillaud, Denis; Le Merre, Charles; Martinat, Yan; Aguilaniu, Bernard; Pavia, Demetri

    2007-01-01

    This was a multicenter, randomized, double-blind within device, parallel-group, dose-ranging study. COPD patients (n = 202; 86% male; mean age: 61 years) were randomized to receive tiotropium 1.25 microg, 2.5 microg, 5 microg, 10 microg, or 20 microg Respimat SMI (a novel, propellant-free device); tiotropium 18 microg HandiHaler; placebo Respimat; or placebo HandiHaler for 3 weeks. The primary endpoint was trough FEV1 on Day 21. Other assessments included FVC, PEFR, rescue medication use, safety, and pharmacokinetics. In general, all active treatments improved the primary and secondary endpoints on Day 21 (steady state) compared with placebo. Tiotropium 5 microg Respimat, 20 microg Respimat, and tiotropium 18 microg HandiHaler were statistically significantly higher than placebo for the primary endpoint (mean change in trough FEV1 was 150 mL (both Respimat doses) versus 20 mL (placebo Respimat); p < 0.05; and 230 mL (HandiHaler) versus -90 mL (placebo HandiHaler); p < or = 0.001). The urinary excretion (up to 2 hours post-dose) of tiotropium 5-10 microg Respimat was comparable with tiotropium 18 microg HandiHaler; the overall incidence of adverse events was comparable across treatment groups. Tiotropium 5 and 10 microg Respimat improve lung function in COPD patients and appear to be comparable with tiotropium 18 microg HandiHaler.

  11. First in situ TOF-PET study using digital photon counters for proton range verification

    NASA Astrophysics Data System (ADS)

    Cambraia Lopes, P.; Bauer, J.; Salomon, A.; Rinaldi, I.; Tabacchini, V.; Tessonnier, T.; Crespo, P.; Parodi, K.; Schaart, D. R.

    2016-08-01

    Positron emission tomography (PET) is the imaging modality most extensively tested for treatment monitoring in particle therapy. Optimal use of PET in proton therapy requires in situ acquisition of the relatively strong 15O signal due to its relatively short half-life (~2 min) and high oxygen content in biological tissues, enabling shorter scans that are less sensitive to biological washout. This paper presents the first performance tests of a scaled-down in situ time-of-flight (TOF) PET system based on digital photon counters (DPCs) coupled to Cerium-doped Lutetium Yttrium Silicate (LYSO:Ce) crystals, providing quantitative results representative of a dual-head tomograph that complies with spatial constraints typically encountered in clinical practice (2  ×  50°, of 360°, transaxial angular acceptance). The proton-induced activity inside polymethylmethacrylate (PMMA) and polyethylene (PE) phantoms was acquired within beam pauses (in-beam) and immediately after irradiation by an actively-delivered synchrotron pencil-beam, with clinically relevant 125.67 MeV/u, 4.6  ×  108 protons s-1, and 1010 total protons. 3D activity maps reconstructed with and without TOF information are compared to FLUKA simulations, demonstrating the benefit of TOF-PET to reduce limited-angle artefacts using a 382 ps full width at half maximum coincidence resolving time. The time-dependent contributions from different radionuclides to the total count-rate are investigated. We furthermore study the impact of the acquisition time window on the laterally integrated activity depth-profiles, with emphasis on 2 min acquisitions starting at different time points. The results depend on phantom composition and reflect the differences in relative contributions from the radionuclides originating from carbon and oxygen. We observe very good agreement between the shapes of the simulated and measured activity depth-profiles for post-beam protocols. However, our results also

  12. First in situ TOF-PET study using digital photon counters for proton range verification.

    PubMed

    Cambraia Lopes, P; Bauer, J; Salomon, A; Rinaldi, I; Tabacchini, V; Tessonnier, T; Crespo, P; Parodi, K; Schaart, D R

    2016-08-21

    Positron emission tomography (PET) is the imaging modality most extensively tested for treatment monitoring in particle therapy. Optimal use of PET in proton therapy requires in situ acquisition of the relatively strong (15)O signal due to its relatively short half-life (~2 min) and high oxygen content in biological tissues, enabling shorter scans that are less sensitive to biological washout. This paper presents the first performance tests of a scaled-down in situ time-of-flight (TOF) PET system based on digital photon counters (DPCs) coupled to Cerium-doped Lutetium Yttrium Silicate (LYSO:Ce) crystals, providing quantitative results representative of a dual-head tomograph that complies with spatial constraints typically encountered in clinical practice (2  ×  50°, of 360°, transaxial angular acceptance). The proton-induced activity inside polymethylmethacrylate (PMMA) and polyethylene (PE) phantoms was acquired within beam pauses (in-beam) and immediately after irradiation by an actively-delivered synchrotron pencil-beam, with clinically relevant 125.67 MeV/u, 4.6  ×  10(8) protons s(-1), and 10(10) total protons. 3D activity maps reconstructed with and without TOF information are compared to FLUKA simulations, demonstrating the benefit of TOF-PET to reduce limited-angle artefacts using a 382 ps full width at half maximum coincidence resolving time. The time-dependent contributions from different radionuclides to the total count-rate are investigated. We furthermore study the impact of the acquisition time window on the laterally integrated activity depth-profiles, with emphasis on 2 min acquisitions starting at different time points. The results depend on phantom composition and reflect the differences in relative contributions from the radionuclides originating from carbon and oxygen. We observe very good agreement between the shapes of the simulated and measured activity depth-profiles for post-beam protocols. However, our results

  13. A multi-range approach for Cultural Heritage survey: a case study in Mantua Unesco site

    NASA Astrophysics Data System (ADS)

    Chiarini, S.; Cremonesi, S.; Fregonese, L.; Fassi, F.; Taffurelli, L.

    2014-06-01

    In this paper, a Cultural Heritage survey, performed by employing and integrating different type of acquisition technologies (imagebased and active sensor based) is presented. The aim of the survey is to create a 3D multiscale database, therefore, different restitution scales, from the architectural-urban one to a detail one are taken in consideration. This research is part of a project financed by the Unesco for the study of historical gardens located in Mantua and Sabbioneta, and in particular for the Palazzo Te renaissance gardens in Mantua, which are reported in this paper. First of all, a general survey of the area has been realized by employing the classical aerial photogrammetry in order to provide the actual arboreal and urban furniture conditions of the gardens (1:500 scale). Next, a detailed photogrammetric survey of the Esedra courtyard in Palazzo Te has been performed by using a UAV system. At the end, laser scanning and traditional topography have been used for the terrestrial detailed acquisition of gardens and architectural façades (1:50-1:20 scale). The aim of this research is to create a suitable graphical documentation support for the study of the structure of the gardens, to analyze how they have been modified over the years and as an effective support for eventual future re-design. Moreover, the research has involved a certain number of botanic and archeological investigations, which have been duly acquired and modeled with image based systems. Starting from the acquired datasets with their acquisition scales, a series of comparative analysis have been performed, especially for those areas in which all the systems have been employed. The comparisons have been extracted by analyzing point cloud models obtained by using a topographical network. As a result, the multi-range approach efficiency, obtained by employing the actual available technologies have been illustrated in the present work.

  14. TSDC study of XLPE recrystallization effects in the melting range of temperatures

    NASA Astrophysics Data System (ADS)

    Diego, J. A.; Belana, J.; Òrrit, J.; Sellarès, J.; Mudarra, M.; Cañadas, J. C.

    2006-05-01

    The electrical properties of crosslinked polyethylene (XLPE), employed in mid-voltage cable insulation are studied using thermally stimulated depolarization currents (TSDC), differential scanning calorimetry (DSC) and x-ray diffraction. A complex heteropolar peak appears by TSDC between 50 and 110 °C, with a maximum at 105 °C. These measurements reveal that there is an optimal polarization temperature (Tpo) around 90 °C. For this polarization temperature, the measured discharge peak area is maximum. Although the presence of a Tpo is common in the study of relaxations by TSDC, in this case one would expect a monotonic decrease in the TSDC response with increasing polarization temperatures due to the decrease in the total crystalline fraction. In this paper, TSDC curves obtained under several conditions are interpreted in terms of recrystallization processes in XLPE during the polarization stage, if the sample is polarized in the melting temperature range. In this case, the recrystallization of a fraction of the material molten at this temperature promotes the formation of more stable and defect-free crystals. The presence of recrystallization processes is detected by DSC and confirmed by x-ray diffractometry. TSDC measurements have been performed with samples polarized at several temperatures (Tp) cooling from the melt or heating from room temperature. Also, TSDC results are obtained with previous annealing or with several cooling rates. These results allow us to infer that crystalline material grown from recrystallization processes that take place in the polarization stage attains a particularly stable polarization. Possible microscopical causes of this effect are discussed.

  15. Aging and Phase Stability Studies of Alloy 22 FY08 Final Report

    SciTech Connect

    Torres, S G

    2008-04-03

    This report is a compilation of work done over the past ten years in support of phase stability studies of Alloy 22 for the Yucca Mountain Project and contains information previously published, reported, and referenced. Most sections are paraphrased here for the convenience of readers. Evaluation of the fabrication processes involved in the manufacture of waste containers is important as these processes can have an effect on the metallurgical structure of an alloy. Because material properties such as strength, toughness, aging kinetics and corrosion resistance are all dependent on the microstructure, it is important that prototypes be built and evaluated for processing effects on the performance of the material. Of particular importance are welds, which have an as-cast microstructure with chemical segregation and precipitation of complex phases resulting from the welding process. The work summarized in this report contains information on the effects of fabrication processes such as solution annealing, stress mitigation, heat-to-heat variability, and welding on the kinetics of precipitation, mechanical, and corrosion properties. For a waste package lifetime of thousands of years, it is impossible to test directly in the laboratory the behavior of Alloy 22 under expected repository conditions. The changes that may occur in these materials must be accelerated. For phase stability studies, this is achieved by accelerating the phase transformations by increasing test temperatures above those anticipated in the proposed repository. For these reasons, Alloy 22 characterization specimens were aged at Lawrence Livermore National Laboratory (LLNL) Aging Facilities for times from 1 hour up to 8 years at temperatures ranging from 200-750 C. These data as well as the data from specimens aged at 260 C, 343 C, and 427 C for 100,028 hours at Haynes International will be used for performance confirmation and model validation.

  16. Reference ranges of handgrip strength from 125,462 healthy adults in 21 countries: a prospective urban rural epidemiologic (PURE) study

    PubMed Central

    Teo, Koon K.; Rangarajan, Sumathy; Kutty, V. Raman; Lanas, Fernando; Hui, Chen; Quanyong, Xiang; Zhenzhen, Qian; Jinhua, Tang; Noorhassim, Ismail; AlHabib, Khalid F; Moss, Sarah J.; Rosengren, Annika; Akalin, Ayse Arzu; Rahman, Omar; Chifamba, Jephat; Orlandini, Andrés; Kumar, Rajesh; Yeates, Karen; Gupta, Rajeev; Yusufali, Afzalhussein; Dans, Antonio; Avezum, Álvaro; Lopez‐Jaramillo, Patricio; Poirier, Paul; Heidari, Hosein; Zatonska, Katarzyna; Iqbal, Romaina; Khatib, Rasha; Yusuf, Salim

    2016-01-01

    Abstract Background The measurement of handgrip strength (HGS) has prognostic value with respect to all‐cause mortality, cardiovascular mortality and cardiovascular disease, and is an important part of the evaluation of frailty. Published reference ranges for HGS are mostly derived from Caucasian populations in high‐income countries. There is a paucity of information on normative HGS values in non‐Caucasian populations from low‐ or middle‐income countries. The objective of this study was to develop reference HGS ranges for healthy adults from a broad range of ethnicities and socioeconomically diverse geographic regions. Methods HGS was measured using a Jamar dynamometer in 125,462 healthy adults aged 35‐70 years from 21 countries in the Prospective Urban Rural Epidemiology (PURE) study. Results HGS values differed among individuals from different geographic regions. HGS values were highest among those from Europe/North America, lowest among those from South Asia, South East Asia and Africa, and intermediate among those from China, South America, and the Middle East. Reference ranges stratified by geographic region, age, and sex are presented. These ranges varied from a median (25th–75th percentile) 50 kg (43–56 kg) in men <40 years from Europe/North America to 18 kg (14–20 kg) in women >60 years from South East Asia. Reference ranges by ethnicity and body‐mass index are also reported. Conclusions Individual HGS measurements should be interpreted using region/ethnic‐specific reference ranges. PMID:27104109

  17. Hemodynamic Correlates of Blood Pressure Across the Adult Age Spectrum: Noninvasive Evaluation in the Framingham Heart Study

    PubMed Central

    Mitchell, Gary F.; Wang, Na; Palmisano, Joseph N.; Larson, Martin G.; Hamburg, Naomi M.; Vita, Joseph A.; Levy, Daniel; Benjamin, Emelia J.; Vasan, Ramachandran S.

    2010-01-01

    Background Systolic blood pressure and pulse pressure are substantially higher in older adults. The relative contributions of increased forward versus reflected pressure wave amplitude or earlier arrival of the reflected wave to elevated pulse pressure remain controversial. Methods and Results We measured proximal aortic pressure and flow, forward pressure wave amplitude, global wave reflection, reflected wave timing and pulse wave velocity noninvasively in 6417 (age range, 19 to 90 years; 53% women) Framingham Heart Study Third Generation and Offspring participants. Variation in forward wave amplitude paralleled pulse pressure throughout adulthood. In contrast, wave reflection and pulse pressure were divergent across adulthood: in younger participants, pulse pressure was lower and wave reflection higher with advancing age whereas in older participants, pulse pressure was higher and wave reflection lower with age. Reflected wave timing differed modestly across age groups despite considerable differences in pulse wave velocity. Forward wave amplitude explained 80% (central) and 66% (peripheral) of the variance in pulse pressure in younger participants (<50 years) and 90% and 84% in the older participants (≥50 years, all P<0.0001). In a stepwise model that evaluated age-pulse pressure relations in the full sample, the late accelerated increases in central and peripheral pulse pressure were markedly attenuated when variation in forward wave amplitude was considered. Conclusions Higher pulse pressure at any age and higher pulse pressure with advancing age is predominantly associated with a larger forward pressure wave. The influence of wave reflection on age-related differences in pulse pressure was minor. PMID:20855656

  18. Radiologic assessment of third molar tooth and spheno-occipital synchondrosis for age estimation: a multiple regression analysis study.

    PubMed

    Demirturk Kocasarac, Husniye; Sinanoglu, Alper; Noujeim, Marcel; Helvacioglu Yigit, Dilek; Baydemir, Canan

    2016-05-01

    For forensic age estimation, radiographic assessment of third molar mineralization is important between 14 and 21 years which coincides with the legal age in most countries. The spheno-occipital synchondrosis (SOS) is an important growth site during development, and its use for age estimation is beneficial when combined with other markers. In this study, we aimed to develop a regression model to estimate and narrow the age range based on the radiologic assessment of third molar and SOS in a Turkish subpopulation. Panoramic radiographs and cone beam CT scans of 349 subjects (182 males, 167 females) with age between 8 and 25 were evaluated. Four-stage system was used to evaluate the fusion degree of SOS, and Demirjian's eight stages of development for calcification for third molars. The Pearson correlation indicated a strong positive relationship between age and third molar calcification for both sexes (r = 0.850 for females, r = 0.839 for males, P < 0.001) and also between age and SOS fusion for females (r = 0.814), but a moderate relationship was found for males (r = 0.599), P < 0.001). Based on the results obtained, an age determination formula using these scores was established.

  19. Pyrolysis-AMS Study of Age Structure of SOC in Volcanic Soils on Kohala Volcano, Hawaii

    NASA Astrophysics Data System (ADS)

    Grant, K. E.; Galy, V.; Derry, L. A.

    2014-12-01

    Soil organic carbon (SOC) is a complex substrate; the soil matrix has a wide array of chemical inputs, leading to a heterogeneous mixture of carbon compounds. In volcanic soils on Kohala Mountain, Hawaii Island, old organic carbon (OC) (>10,000 years) is associated with short-range order (SRO) minerals with large, reactive surface areas (Torn et al., 1997). Large variations in precipitation generate significant changes in soil pH, secondary minerals and soil redox state. A study to measure the age distribution in a given sample of SOC by the ramped pyrolysis-AMS technique was carried out at Woods Hole NOSAMS facility. Five soil samples, from three sites (precipitation = 2.4m/year, 2.3m/year, 1.78m/year, respectively) on a 350 ka volcanic (Pololu) substrate were analyzed. Samples were freeze-dried, homogenized, and combusted under a programed temperature pyrolysis regime from 25 to 900°C; evolved CO2 was collected in fractions for 14C analysis. The abundance of SRO minerals is characterized through sequential extractions and total elemental analysis. Results include: 1.) The Pu'u Eke profile (2.4m/year), older carbon (bulk radiocarbon age: 2530 years) is deeper (63-74cm) in the soil profile, but it is thermally less stable (thermograph Tmax: 314°C) than the younger carbon, which was in the associated with the 25-36cm sample (radiocarbon age: 1030yr) and Tmax: 324°C. The top horizon of the profile (13-21cm) had a modern radiocarbon age, but a Tmax: 396°C. 2.) The high precipitation site has significantly younger OC (2698 yr) than the drier site (7585 yr). This is coincident with changing redox conditions and loss of nano-crystalline iron oxide minerals (ferrihydrite) from the wet site. 3.) In a given sample, the age distribution is fairly uniform. The initial results support the hypothesis that nano-crystalline ferrihydrite acts to stabilize OC, as older carbon is found in the dryer, ferrihydrite rich sites, while at the wet, Fe-poor site 14C ages were

  20. Time-Constrained Functional Connectivity Analysis of Cortical Networks Underlying Phonological Decoding in Typically Developing School-Aged Children: A Magnetoencephalography Study

    ERIC Educational Resources Information Center

    Simos, Panagiotis G.; Rezaie, Roozbeh; Fletcher, Jack M.; Papanicolaou, Andrew C.

    2013-01-01

    The study investigated functional associations between left hemisphere occipitotemporal, temporoparietal, and inferior frontal regions during oral pseudoword reading in 58 school-aged children with typical reading skills (aged 10.4 [plus or minus] 1.6, range 7.5-12.5 years). Event-related neuromagnetic data were used to compute source-current…

  1. A descriptive survey study on the effect of age on quality of life following stoma surgery.

    PubMed

    Wong, Selina K; Young, Pang Y; Widder, Sandy; Khadaroo, Rachel G

    2013-12-01

    The number of operative procedures involving the creation of an intestinal stoma is likely to increase as the population ages. Understanding the role of age on postoperative outcomes such as quality of life (QoL) and self-efficacy is critical to developing appropriate supportive strategies. A descriptive survey study was conducted among 18 patients (11 men seven women, age range 47 to 90 years) who had an intestinal ostomy created during a 3-year period at the University of Alberta Hospital in Edmonton, Alberta, Canada. The Stoma Quality of Life Survey and a self-efficacy survey examining self-care, activities of daily living, and instrumental activities of daily living were administered. Patient records were obtained through a retrospective chart review; of the 57 patients identified, 18 were still alive, had not undergone stoma reversal, were cognitively competent, and agreed to participate. Seven patients were <65 years old and 11 were ≥65 years old. Of those, four patients had their stoma since 2009, four patients since 2010, and 10 patients since 2011. Although older patients had more comorbidities and higher mortality following the surgery (46.1% for patients >65 versus 26.1%, for patients <65 years old), no statistically significant difference was found between the two groups for stoma-associated QoL and self-efficacy scores. In patients who had stoma surgery in 2011, older patients on average had higher QoL scores (65.21 versus 61.87, maximum score 100, P = 0.56), but lower self-efficacy scores (32.50 versus 35.25, maximum score 40, P = 0.50). These findings are similar to previously reported study results. However, the small study sample size limits analysis of the variables that may affect QoL in stoma patients. This study supports the need for additional prospective studies to help clinicians develop effective support strategies.

  2. Long Range Spoil Disposal Study. Part I. General Data for the Delaware River,

    DTIC Science & Technology

    1969-01-01

    Horseshoe Range (west side) 40 400-500 Allegheny Ave., Phila. - W. Horseshoe Range (east side) 37 500-600 W. Horseshoe Range - Bombay Hook Pt. 40 800 Bombay...Authorized Anchorage 13,650 2,300 8 Thompson Point Tinicumlsland E side of Channel 3,400 700-1300 betw Crab Pt & Monds Island 9 Mantua Creek Mifflin Bar...Authorized Anchorage 11,500 2,300 10 Naval Base W Horseshoe W side of Channel 2,600 12-1500 (League Island) 11 Gloucester E Horseshoe Authorized

  3. A study of remote spatial memory in aged rats.

    PubMed

    Winocur, Gordon; Moscovitch, Morris; Rosenbaum, R Shayna; Sekeres, Melanie

    2010-01-01

    The effect of aging on remote spatial memory was tested in a group of 2-year-old rats (VR-O) that, as young adults, were reared for 3 months in a complex 'village' environment. The VR-O rats exhibited significant savings in finding the locations of specific reward compartments within the village, relative to a group of old rats (VNR-O) experiencing the village for the first time. The VNR-O rats were also impaired, relative to naive young rats, in learning the reward locations. Probe tests indicated that the VR-O rats retained allocentric spatial memory for the environment and were not using sensory or other non-spatial cues to guide behaviour. Overall, the results indicate that the aged rats experienced a decline in the ability to learn and remember detailed spatial relationships and that the VR-O group's successful performance on the remote spatial memory test was guided by a form of schematic memory that captured the essential features of the village environment. The potential contribution of the hippocampus to the pattern of lost and spared learning and memory observed in the aged rats was discussed.

  4. Age, growth rates, and paleoclimate studies of deep sea corals

    USGS Publications Warehouse

    Prouty, Nancy G; Roark, E. Brendan; Andrews, Allen; Robinson, Laura; Hill, Tessa; Sherwood, Owen; Williams, Branwen; Guilderson, Thomas P.; Fallon, Stewart

    2015-01-01

    Deep-water corals are some of the slowest growing, longest-lived skeletal accreting marine organisms. These habitat-forming species support diverse faunal assemblages that include commercially and ecologically important organisms. Therefore, effective management and conservation strategies for deep-sea corals can be informed by precise and accurate age, growth rate, and lifespan characteristics for proper assessment of vulnerability and recovery from perturbations. This is especially true for the small number of commercially valuable, and potentially endangered, species that are part of the black and precious coral fisheries (Tsounis et al. 2010). In addition to evaluating time scales of recovery from disturbance or exploitation, accurate age and growth estimates are essential for understanding the life history and ecology of these habitat-forming corals. Given that longevity is a key factor for population maintenance and fishery sustainability, partly due to limited and complex genetic flow among coral populations separated by great distances, accurate age structure for these deep-sea coral communities is essential for proper, long-term resource management.

  5. Reference ranges of PR duration and P-wave indices in individuals free of cardiovascular disease: the Multi-Ethnic Study of Atherosclerosis (MESA)

    PubMed Central

    Soliman, Elsayed Z; Alonso, Alvaro; Misialek, Jeffrey R.; Jain, Aditya; Watson, Karol E.; Lloyd-Jones, Don; Lima, Joao; Shea, Steven; Burke, Gregory L; Heckbert, Susan R.

    2013-01-01

    In this brief report, we provide normal reference ranges for PR duration [unadjusted and heart rate adjusted] and P-wave indices [duration, amplitude and terminal force in V1] in individuals free of cardiovascular disease and its risk factors. We used automatically processed digital ECG data from 1252 US participants [mean age 59 (± 10) years, 738 women, 588 whites, 207 African-Americans, 217 Hispanics, 240 Chinese] from the Multi-Ethnic Study of Atherosclerosis [MESA]. In multivariable adjusted linear regression models with PR and each P-wave variable as a separate outcome, significant age, sex and race differences in these markers were observed. Subsequently, we report reference ranges for abnormal [2nd and 98th percentiles], borderline abnormal [5th and 95th percentiles] and mean [SD] values of PR and P-wave indices stratified by age [middle age (45–64 years) and seniors (65–84 years)], sex [men and women] and race [whites, African Americans, Hispanics and Chinese]. PMID:23806475

  6. Using CForest to Analyze Diffusion Tensor Imaging Data: A Study of White Matter Integrity in Healthy Aging.

    PubMed

    McWhinney, Sean R; Tremblay, Antoine; Chevalier, Thérèse M; Lim, Vanessa K; Newman, Aaron J

    2016-12-01

    Healthy aging has been associated with a global reduction in white matter integrity, which is thought to reflect cognitive decline. The present study aimed to investigate this reduction over a broad range of the life span, using diffusion tensor imaging analyzed with conditional inference random forest modeling (CForest). This approach is sensitive to subtle and potentially nonlinear effects over the age continuum and was used to characterize the progression of decline in greater detail than has been possible in the past. Data were collected from 45 healthy individuals ranging in age from 19 to 67 years. Fractional anisotropy (FA) was estimated using probabilistic tractography for a number of major tracts across the brain. Age coincided with a nonlinear decrease in FA, with onset beginning at ∼30 years of age and the steepest declines occurring later in life. However, several tracts showed a transient increase before this decline. The progression of decline varied by tract, with steeper but later decline occurring in more anterior tracts. Finally, strongly right-handed individuals demonstrated relatively preserved FA until more than a decade following the onset of decline of others. These results demonstrate that using a novel, nonparametric analysis approach, previously reported reductions in FA with healthy aging were confirmed, while at the same time, new insight was provided into the onset and progression of decline, with evidence suggesting increases in integrity continuing into adulthood.

  7. Four Week Oral (Gavage) Dose Range-Finding Study of Halofantrine Hydrochloride in Mice

    DTIC Science & Technology

    1994-10-26

    Because marginal halofantrine- induced toxicity was seen in low dose females, the following dose level ranges are suggested: 1 - 2, 4 - 8 and 15-30 mg/kg...halofantrine- induced toxicity was seen in low dose females, the following dose level ranges are suggested: 1 - 2, 4 - 8 and 15-30 mg/kg/day. 2...selected on the basis of Sponsor-supplied subchronic toxicity data in rats and following discussions with the Sponsor. During the test animal selection

  8. Grenade Range Management Using Lime for Metals Immobilization and Explosives Transformation Treatability Study

    DTIC Science & Technology

    2007-06-01

    Calcitic hydrated lime K2CO3 Potassium carbonate KOH Potassium hydroxide NaOH Sodium hydroxide NH3-N Nitrogen-ammonia NO2/NO3 Nitrite/nitrate...munitions residues, metals are not degraded or easily detoxified. The most com- monly used treatment technologies for metals in soils on firing ranges...of an active firing range. Alkaline hydrolysis The use of the hydrolysis reaction as a means to degrade various environ- mental contaminants is

  9. A case study on the perception of aging and participation in physical activities of older Chinese immigrants in Australia.

    PubMed

    Koo, Fung Kuen

    2011-10-01

    This qualitative study explores how older Hong Kong ChineseAustralians perceive aging and to what extent this perception affects their participation in physical activities. The main methods used were in-depth interviews with 22 participants ranging in age from 60 to 91 years. Interviews were translated from Chinese (Cantonese) and transcribed into English. Content analysis was used to find recurring themes from the interview data. The main findings indicate that the perception of aging is to some extent influenced by culture. Some participants defined aging as being measured in years, and others defined it by the state of one's physical health, appearance, and capacity to continue fulfilling one's social roles. These perceptions strongly influenced their preferences for and participation in physical activities. Acknowledging the fact that Chinese-speaking people are not culturally homogeneous, this article makes some recommendations to health service providers with regard to the development of appropriate physical activity programs.

  10. An Aging Interventions Testing Program: study design and interim report.

    PubMed

    Miller, Richard A; Harrison, David E; Astle, Clinton M; Floyd, Robert A; Flurkey, Kevin; Hensley, Kenneth L; Javors, Martin A; Leeuwenburgh, Christiaan; Nelson, James F; Ongini, Ennio; Nadon, Nancy L; Warner, Huber R; Strong, Randy

    2007-08-01

    The National Institute on Aging's Interventions Testing Program (ITP) has developed a plan to evaluate agents that are considered plausible candidates for delaying rates of aging. Key features include: (i) use of genetically heterogeneous mice (a standardized four-way cross), (ii) replication at three test sites (the Jackson Laboratory, TJL; University of Michigan, UM; and University of Texas, UT), (iii) sufficient statistical power to detect 10% changes in lifespan, (iv) tests for age-dependent changes in T cell subsets and physical activity, and (v) an annual solicitation for collaborators who wish to suggest new interventions for evaluation. Mice in the first cohort were exposed to one of four agents: aspirin, nitroflurbiprofen (NFP), 4-OH-alpha-phenyl-N-tert-butyl nitrone (4-OH-PBN), or nordihydroguiaretic acid (NDGA). An interim analysis was conducted using survival data available on the date at which at least 50% of the male control mice had died at each test site. Survival of control males was significantly higher, at the interim time-point, at UM than at UT or TJL; all three sites had similar survival of control females. Males in the NDGA group had significantly improved survival (P = 0.0004), with significant effects noted at TJL (P < 0.01) and UT (P < 0.04). None of the other agents altered survival, although there was a suggestion (P = 0.07) of a beneficial effect of aspirin in males. More data will be needed to determine if any of these compounds can extend maximal lifespan, but the current data show that NDGA reduces early life mortality risks in genetically heterogeneous mice at multiple test sites.

  11. The global status of freshwater fish age validation studies and a prioritization framework for future research

    USGS Publications Warehouse

    Pope, Kevin L.; Hamel, Martin J.; Pegg, Mark A.; Spurgeon, Jonathan J.

    2016-01-01

    Age information derived from calcified structures is commonly used to estimate recruitment, growth, and mortality for fish populations. Validation of daily or annual marks on age structures is often assumed, presumably due to a lack of general knowledge concerning the status of age validation studies. Therefore, the current status of freshwater fish age validation studies was summarized to show where additional effort is needed, and increase the accessibility of validation studies to researchers. In total, 1351 original peer-reviewed articles were reviewed from freshwater systems that studied age in fish. Periodicity and age validation studies were found for 88 freshwater species comprising 21 fish families. The number of age validation studies has increased over the last 30 years following previous calls for more research; however, few species have validated structures spanning all life stages. In addition, few fishes of conservation concern have validated ageing structures. A prioritization framework, using a combination of eight characteristics, is offered to direct future age validation studies and close the validation information gap. Additional study, using the offered prioritization framework, and increased availability of published studies that incorporate uncertainty when presenting research results dealing with age information are needed.

  12. Predictors and Characteristics of Successful Aging among Men: A 48-Year Longitudinal Study

    ERIC Educational Resources Information Center

    Westermeyer, Jerry F.

    2013-01-01

    To explore dimensions of successful aging, 71 men were selected for healthy adjustment and were prospectively studied in young adulthood (average age 20) and reassessed in 32-year and 48-year follow-ups. Despite an increase of medical problems, most men maintained healthy adjustment in early old age. At both follow-ups, successful young adult…

  13. A Study of the Relationship Between Gesell's Developmental Age and Piaget's Concept of Conservation.

    ERIC Educational Resources Information Center

    Civretta, Adeline E.

    A study was conducted to determine whether a significant correlation exists between developmental age and the concept of conservation. The hypothesis was that if developmental age and the concept of conservation are related, then stages of understanding conservation will increase as developmental age increases. Ss consisted of 30 primary children…

  14. Social Studies Classroom Activities for Secondary Schools. Schools in an Aging Society.

    ERIC Educational Resources Information Center

    Goranson, Donald G., Ed.

    Designed for secondary students, the 20 lessons in this volume promote education for, with, and about older adults and prepare students to participate in the changing world. Lessons 1-3 explore attitudes about aging through word association, confront the aging process, and examine values regarding time. Lessons 4-6 study aging in different times…

  15. Theoretical and Experimental Study on Wide Range Optical Fiber Turbine Flow Sensor

    PubMed Central

    Du, Yuhuan; Guo, Yingqing

    2016-01-01

    In this paper, a novel fiber turbine flow sensor was proposed and demonstrated for liquid measurement with optical fiber, using light intensity modulation to measure the turbine rotational speed for converting to flow rate. The double-circle-coaxial (DCC) fiber probe was introduced in frequency measurement for the first time. Through the divided ratio of two rings light intensity, the interference in light signals acquisition can be eliminated. To predict the characteristics between the output frequency and flow in the nonlinear range, the turbine flow sensor model was built. Via analyzing the characteristics of turbine flow sensor, piecewise linear equations were achieved in expanding the flow measurement range. Furthermore, the experimental verification was tested. The results showed that the flow range ratio of DN20 turbine flow sensor was improved 2.9 times after using piecewise linear in the nonlinear range. Therefore, combining the DCC fiber sensor and piecewise linear method, it can be developed into a strong anti-electromagnetic interference(anti-EMI) and wide range fiber turbine flowmeter. PMID:27428976

  16. INTEGRATING PARASITES AND PATHOGENS INTO THE STUDY OF GEOGRAPHIC RANGE LIMITS.

    PubMed

    Bozick, Brooke A; Real, Leslie A

    2015-12-01

    The geographic distributions of all species are limited, and the determining factors that set these limits are of fundamental importance to the fields of ecology and evolutionary biology. Plant and animal ranges have been of primary concern, while those of parasites, which represent much of the Earth's biodiversity, have been neglected. Here, we review the determinants of the geographic ranges of parasites and pathogens, and explore how parasites provide novel systems with which to investigate the ecological and evolutionary processes governing host/parasite spatial distributions. Although there is significant overlap in the causative factors that determine range borders of parasites and free-living species, parasite distributions are additionally constrained by the geographic range and ecology of the host species' population, as well as by evolutionary factors that promote host-parasite coevolution. Recently, parasites have been used to infer population demographic and ecological information about their host organisms and we conclude that this strategy can be further exploited to understand geographic range limitations of both host and parasite populations.

  17. A study of the age attribute in a query tool for a clinical data warehouse.

    PubMed

    Scheufele, Elisabeth L; Scheufele, Elisabeth Lee; Dubey, Anil; Dubey, Anil Kumar; Murphy, Shawn N

    2008-11-06

    The RPDR, a clinical data warehouse with a user-friendly Querytool, allows researchers to perform studies on patient data. Currently, the RPDR represents age as the patient's age at the present time, which is problematic in situations where age at the time of the event is more appropriate. We will modify the Querytool to consider this by assessing the perception of age via survey, testing backend query solutions, and developing modifications based on these results.

  18. Study of heavy ion range in different solid state nuclear track detector materials

    NASA Astrophysics Data System (ADS)

    Diwan, P. K.; Singh, Lakhwant; Singh, Gurinder; Kumar, Shyam

    2000-03-01

    The range of several heavy ions as 238U, 208Pb, 197Au, 139La, 58Ni and 56Fe in sodalime glass; 197Au and 58Ni in muscovite mica and Lexan polycarbonate; 209Bi and 197Au in CR-39 have been determined experimentally. The calculations of range for these projectile-target combinations have been made using the Benton and Henke [10], Mukherjee and Nayak [11], Ziegler et al. [12] and Hubert et al. [14] semiempirical formulations. Finally a comparison has been made with the experimental results.

  19. Long-range airplane study: The consumer looks at SST travel

    NASA Technical Reports Server (NTRS)

    Landes, K. H.; Matter, J. A.

    1980-01-01

    The attitudes of long-range air travelers toward several basic air travel decisions, were surveyed. Of interest were tradeoffs involving time versus comfort and time versus cost as they pertain to supersonic versus conventional wide-body aircraft on overseas routes. The market focused upon was the segment of air travelers most likely to make that type of tradeoff decision: those having flown overseas routes for business or personal reasons in the recent past. The information generated is intended to provide quantifiable insight into consumer demand for supersonic as compared to wide-body aircraft alternatives for long-range overseas air travel.

  20. Genetic variants influencing human aging from late-onset Alzheimer’s disease (LOAD) genome-wide association studies (GWAS)

    PubMed Central

    Shi, Hui; Belbin, Olivia; Medway, Christopher; Brown, Kristelle; Kalsheker, Noor; Carrasquillo, Minerva; Proitsi, Petroula; Powell, John; Lovestone, Simon; Goate, Alison; Younkin, Steven; Passmore, Peter; Morgan, Kevin

    2014-01-01

    Genetics plays a crucial role in human aging with up to 30% of those living to the mid-80s being determined by genetic variation. Survival to older ages likely entails an even greater genetic contribution. There is increasing evidence that genes implicated in age-related diseases, such as cancer and neuronal disease, play a role in affecting human life span. We have selected the 10 most promising late-onset Alzheimer’s disease (LOAD) susceptibility genes identified through several recent large genome-wide association studies (GWAS). These 10 LOAD genes (APOE, CLU, PICALM, CR1, BIN1, ABCA7, MS4A6A, CD33, CD2AP, and EPHA1) have been tested for association with human aging in our dataset (1385 samples with documented age at death [AAD], age range: 58–108 years; mean age at death: 80.2) using the most significant single nucleotide polymorphisms (SNPs) found in the previous studies. Apart from the APOE locus (rs2075650) which showed compelling evidence of association with risk on human life span (p = 5.27 × 10−4), none of the other LOAD gene loci demonstrated significant evidence of association. In addition to examining the known LOAD genes, we carried out analyses using age at death as a quantitative trait. No genome-wide significant SNPs were discovered. Increasing sample size and statistical power will be imperative to detect genuine aging-associated variants in the future. In this report, we also discuss issues relating to the analysis of genome-wide association studies data from different centers and the bioinformatic approach required to distinguish spurious genome-wide significant signals from real SNP associations. PMID:22445811

  1. Preliminary core design studies for the advanced burner reactor over a wide range of conversion ratios.

    SciTech Connect

    Hoffman, E. A.; Yang, W. S.; Hill, R. N.; Nuclear Engineering Division

    2008-05-05

    A consistent set of designs for 1000 MWt commercial-scale sodium-cooled Advance Burner Reactors (ABR) have been developed for both metal and oxide-fueled cores with conversion ratios from breakeven (CR=1.0) to fertile-free (CR=0.0). These designs are expected to satisfy thermal and irradiation damage limits based on the currently available data. The very low conversion ratio designs require fuel that is beyond the current fuel database, which is anticipated to be qualified by and for the Advanced Burned Test Reactor. Safety and kinetic parameters were calculated, but a safety analysis was not performed. Development of these designs was required to achieve the primary goal of this study, which was to generate representative fuel cycle mass flows for system studies of ABRs as part of the Global Nuclear Energy Partnership (GNEP). There are slight variations with conversion ratio but the basic ABR configuration consists of 144 fuel assemblies and between 9 and 22 primary control assemblies for both the metal and oxide-fueled cores. Preliminary design studies indicated that it is feasible to design the ABR to accommodate a wide range of conversion ratio by employing different assembly designs and including sufficient control assemblies to accommodate the large reactivity swing at low conversion ratios. The assemblies are designed to fit within the same geometry, but the size and number of fuel pins within each assembly are significantly different in order to achieve the target conversion ratio while still satisfying thermal limits. Current irradiation experience would allow for a conversion ratio of somewhat below 0.75. The fuel qualification for the first ABR should expand this experience to allow for much lower conversion ratios and higher bunrups. The current designs were based on assumptions about the performance of high and very high enrichment fuel, which results in significant uncertainty about the details of the designs. However, the basic fuel cycle performance

  2. Association of Cognitive Function With Cause-Specific Mortality in Middle and Older Age: Follow-up of Participants in the English Longitudinal Study of Ageing

    PubMed Central

    Batty, G. David; Deary, Ian J.; Zaninotto, Paola

    2016-01-01

    We examined the little-tested associations between general cognitive function in middle and older age and later risk of death from chronic diseases. In the English Longitudinal Study of Ageing (2002–2012), 11,391 study participants who were 50–100 years of age at study induction underwent a battery of cognitive tests and provided a range of collateral data. In an analytical sample of 9,204 people (4,982 women), there were 1,488 deaths during follow-up (mean duration, 9.0 years). When we combined scores from 4 cognition tests that represented 3 acknowledged key domains of cognitive functioning (memory, executive function, and processing speed), cognition was inversely associated with deaths from cancer (per each 1-standard-deviation decrease in general cognitive function score, hazard ratio = 1.21, 95% CI: 1.10, 1.33), cardiovascular disease (hazard ratio = 1.71, 95% CI: 1.55, 1.89), other causes (hazard ratio = 2.07, 95% CI: 1.79, 2.40), and respiratory illness (hazard ratio = 2.48, 95% CI: 2.12, 2.90). Controlling for a range of covariates, such as health behaviors and socioeconomic status, and left-censoring to explore reverse causality had very little impact on the strength of these relationships. These findings indicate that cognitive test scores can provide relatively simple indicators of the risk of death from an array of chronic diseases and that these associations appear to be independent of other commonly assessed risk factors. PMID:26803665

  3. The Wide Range Achievement Test and the Peabody Individual Achievement Test: A Comparative Study.

    ERIC Educational Resources Information Center

    Harmer, William R.; Williams, Fern

    A comparison of the Wide Range Achievement Test (WRAT) and the Peabody Individual Achievement Test (PIAT) indicates that the two should be used interchangeably only with caution and understanding of the differences. While there is a moderate to high correlation between the test scores, nevertheless, the two have distinctly different strengths and…

  4. The Wide Range Achievement Test and the Peabody Individual Achievement Test: A Comparative Study.

    ERIC Educational Resources Information Center

    Harmer, William R.; Williams, Fern

    1978-01-01

    The article presents a statistical and descriptive comparison, with emphasis on math subtests, of the Wide Range Achievement Test and the Peabody Individual Achievement Test, based on scores obtained from clients (in grades 1-12) at a university-affiliated learning disabilities center. (SBH)

  5. Earth rotation parameters from an on-site study of laser ranging data

    NASA Technical Reports Server (NTRS)

    Shelus, Peter J.

    1992-01-01

    A multi-faceted effort was maintained to achieve the following goals: (1) provide for state-of-the-art, on-site, near-real-time Earth orientation parameter determinations at levels of precision and accuracy commensurate with a 'quick-look' type of an analysis, using the lunar laser ranging (LLR) data type from the McDonald Laser Ranging Station (MLRS) and other LLR facilities around the world; (2) create a state-of-the-art, highly transportable, LLR-based Earth orientation solution package, which could be easily implemented at LLR facilities other than the MLRS; (3) accommodate, within the routine MLRS lunar range prediction and Earth orientation data analysis software packages, the standard set of Jet Propulsion Laboratory (JPL) Solar System ephemerides, lunar librations, and Solar System partial derivatives; and (4) examine, wherever possible, opportunities for the performance of state-of-the-art, on-site, joint, simultaneous, quick-look analysis for Earth orientation parameters, using both MLRS lunar and LAGEOS (and, perhaps, Etalon) ranging observations, as well as from multiple LLR station observations. Excellent results were obtained at all levels of effort and it can be said that all of these goals were attained. The reader is referred to the complete series of our semi-annual reports for a full description of our efforts.

  6. How proton pulse characteristics influence protoacoustic determination of proton-beam range: simulation studies.

    PubMed

    Jones, Kevin C; Seghal, Chandra M; Avery, Stephen

    2016-03-21

    The unique dose deposition of proton beams generates a distinctive thermoacoustic (protoacoustic) signal, which can be used to calculate the proton range. To identify the expected protoacoustic amplitude, frequency, and arrival time for different proton pulse characteristics encountered at hospital-based proton sources, the protoacoustic pressure emissions generated by 150 MeV, pencil-beam proton pulses were simulated in a homogeneous water medium. Proton pulses with Gaussian widths ranging up to 200 μs were considered. The protoacoustic amplitude, frequency, and time-of-flight (TOF) range accuracy were assessed. For TOF calculations, the acoustic pulse arrival time was determined based on multiple features of the wave. Based on the simulations, Gaussian proton pulses can be categorized as Dirac-delta-function-like (FWHM < 4 μs) and longer. For the δ-function-like irradiation, the protoacoustic spectrum peaks at 44.5 kHz and the systematic error in determining the Bragg peak range is <2.6 mm. For longer proton pulses, the spectrum shifts to lower frequencies, and the range calculation systematic error increases (⩽ 23 mm for FWHM of 56 μs). By mapping the protoacoustic peak arrival time to range with simulations, the residual error can be reduced. Using a proton pulse with FWHM = 2 μs results in a maximum signal-to-noise ratio per total dose. Simulations predict that a 300 nA, 150 MeV, FWHM = 4 μs Gaussian proton pulse (8.0 × 10(6) protons, 3.1 cGy dose at the Bragg peak) will generate a 146 mPa pressure wave at 5 cm beyond the Bragg peak. There is an angle dependent systematic error in the protoacoustic TOF range calculations. Placing detectors along the proton beam axis and beyond the Bragg peak minimizes this error. For clinical proton beams, protoacoustic detectors should be sensitive to <400 kHz (for -20 dB). Hospital-based synchrocyclotrons and cyclotrons are promising sources of proton pulses for generating clinically measurable protoacoustic

  7. Groundwater-Quality Data in the South Coast Range-Coastal Study Unit, 2008: Results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Burton, Carmen A.; Land, Michael; Belitz, Kenneth

    2010-01-01

    the 70 wells sampled, 3 surface-water samples were collected in streams near 2 of the sampled wells in order to better comprehend the interaction between groundwater and surface water in the area. The groundwater samples were analyzed for organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, polar pesticides and metabolites, and pharmaceutical compounds), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-TCP), naturally occurring inorganic constituents (trace elements, nutrients, dissolved organic carbon [DOC], major and minor ions, silica, total dissolved solids [TDS], and alkalinity), and radioactive constituents (gross alpha and gross beta radioactivity). Naturally occurring isotopes (stable isotopes of hydrogen and oxygen in water, stable isotopes of nitrogen and oxygen in dissolved nitrate, stable isotopes of sulfur in dissolved sulfate, stable isotopes of carbon in dissolved inorganic carbon, activities of tritium, and carbon-14 abundance), and dissolved gases (including noble gases) also were measured to help identify the sources and ages of the sampled groundwater. In total, 298 constituents and field water-quality indicators were investigated. Three types of quality-control samples (blanks, replicates, and matrix-spikes) were collected at approximately 3 to 12 percent of the wells in the SCRC study unit, and the results for these samples were used to evaluate the quality of the data for the groundwater samples. Field blanks rarely contained detectable concentrations of any constituent, suggesting that contamination from sample collection procedures was not a significant source of bias in the data for the groundwater samples. Differences between replicate samples generally were less than 10 percent relative and/or standard deviation, indicating acceptable analytical reproducibility. Matrix-spike recoveries were within the acceptable range (70 to 130 percent) for approximately 84

  8. Home range and travels

    USGS Publications Warehouse

    Stickel, L.F.; King, John A.

    1968-01-01

    The concept of home range was expressed by Seton (1909) in the term 'home region,' which Burr (1940, 1943) clarified with a definition of home range and exemplified in a definitive study of Peromyscus in the field. Burt pointed out the ever-changing characteristics of home-range area and the consequent absence of boundaries in the usual sense--a finding verified by investigators thereafter. In the studies summarized in this paper, sizes of home ranges of Peromyscus varied within two magnitudes, approximately from 0.1 acre to ten acres, in 34 studies conducted in a variety of habitats from the seaside dunes of Florida to the Alaskan forests. Variation in sizes of home ranges was correlated with both environmental and physiological factors; with habitat it was conspicuous, both in the same and different regions. Food supply also was related to size of home range, both seasonally and in relation to habitat. Home ranges generally were smallest in winter and largest in spring, at the onset of the breeding season. Activity and size also were affected by changes in weather. Activity was least when temperatures were low and nights were bright. Effects of rainfall were variable. Sizes varied according to sex and age; young mice remained in the parents' range until they approached maturity, when they began to travel more widely. Adult males commonly had larger home ranges than females, although there were a number of exceptions. An inverse relationship between population density and size of home range was shown in several studies and probably is the usual relationship. A basic need for activity and exploration also appeared to influence size of home range. Behavior within the home range was discussed in terms of travel patterns, travels in relation to home sites and refuges, territory, and stability of size of home range. Travels within the home range consisted of repeated use of well-worn trails to sites of food, shelter, and refuge, plus more random exploratory travels

  9. Age-Related Weakness of Proximal Muscle Studied with Motor Cortical Mapping: A TMS Study

    PubMed Central

    Plow, Ela B.; Varnerin, Nicole; Cunningham, David A.; Janini, Daniel; Bonnett, Corin; Wyant, Alexandria; Hou, Juliet; Siemionow, Vlodek; Wang, Xiao-Feng; Machado, Andre G.; Yue, Guang H.

    2014-01-01

    Aging-related weakness is due in part to degeneration within the central nervous system. However, it is unknown how changes to the representation of corticospinal output in the primary motor cortex (M1) relate to such weakness. Transcranial magnetic stimulation (TMS) is a noninvasive method of cortical stimulation that can map representation of corticospinal output devoted to a muscle. Using TMS, we examined age-related alterations in maps devoted to biceps brachii muscle to determine whether they predicted its age-induced weakness. Forty-seven right-handed subjects participated: 20 young (22.6±0.90 years) and 27 old (74.96±1.35 years). We measured strength as force of elbow flexion and electromyographic activation of biceps brachii during maximum voluntary contraction. Mapping variables included: 1) center of gravity or weighted mean location of corticospinal output, 2) size of map, 3) volume or excitation of corticospinal output, and 4) response density or corticospinal excitation per unit area. Center of gravity was more anterior in old than in young (p<0.001), though there was no significant difference in strength between the age groups. Map size, volume, and response density showed no significant difference between groups. Regardless of age, center of gravity significantly predicted strength (β = −0.34, p = 0.005), while volume adjacent to the core of map predicted voluntary activation of biceps (β = 0.32, p = 0.008). Overall, the anterior shift of the map in older adults may reflect an adaptive change that allowed for the maintenance of strength. Laterally located center of gravity and higher excitation in the region adjacent to the core in weaker individuals could reflect compensatory recruitment of synergistic muscles. Thus, our study substantiates the role of M1 in adapting to aging-related weakness and subtending strength and muscle activation across age groups. Mapping from M1 may offer foundation for an examination of mechanisms

  10. A study of axonal degeneration in the optic nerves of aging mice

    NASA Technical Reports Server (NTRS)

    Johnson, J. E., Jr.; Philpott, D. E.; Miquel, J.

    1978-01-01

    The optic nerves of C57BL/6J mice ranging from 3 to 30 months were examined by electron microscopy. At all ages investigated, optic nerve axons contained enlarged mitochondria with abnormal cristae. With increasing age, a large number of necrotic axons were observed and were in the process of being phagocytized. The abnormal mitochondria may represent preliminary changes that eventually lead to necrosis of the axon.

  11. Long-range and head-on beam-beam compensation studies in RHIC with lessons for the LHC

    SciTech Connect

    Fischer,W.; Luo, Y.; Abreu, N.; Calaga, R.; Montag, C.; Robert-Demolaize, G.; Dorda, U.; Koutchouk, J. -P.; Sterbini, G.; Zimmermann, F.; Kim, H. -J.; Sen, T.; Shiltsev, V.; Valishev, A.; Qiang, J.; Kabel, A.

    2008-11-24

    Long-range as well as head-on beam-beam effects are expected to limit the LHC performance with design parameters. They are also important consideration for the LHC upgrades. To mitigate long-range effects current carrying wires parallel to the beam were proposed. Two such wires are installed in RHIC where they allow studying the effect of strong long-range beam-beam effects, as well as the compensation of a single long-range interaction. The tests provide benchmark data for simulations and analytical treatments. To reduce the head-on beam-beam effect electron lenses were proposed for both RIDC and the LHC. We present the experimental long-range beam-beam program at RHIC and report on head-on compensations studies based on simulations.

  12. Long-Range And Head-On Beam-Beam Compensation Studies in RHIC With Lessons for the LHC

    SciTech Connect

    Fischer, W.; Luo, Y.; Abreu, N.; Calaga, R.; Montag, C.; Robert-Demolaize, G.; Dorda, U.; Koutchouk, J.P.; Sterbini, G.; Zimmermann, F.; Kim, H.J.; Sen, T.; Shiltsev, V.; Valishev, A.; Qiang, J.; Kabel, A.; /SLAC

    2011-11-28

    Long-range as well as head-on beam-beam effects are expected to limit the LHC performance with design parameters. They are are also important consideration for the LHC upgrades. To mitigate long-range effects, current carrying wires parallel to the beam were proposed. Two such wires are installed in RHIC where they allow studying the effect of strong long-range beam-beam effects, as well as the compensation of a single long-range interaction. The tests provide benchmark data for simulations and analytical treatments. Electron lenses were proposed for both RHIC and the LHC to reduce the head-on beam-beam effect. We present the experimental long-range beam-beam program at RHIC and report on head-on compensations studies based on simulations.

  13. Long-range and head-on beam-beam compensation studies in RHIC with lessons for the LHC

    SciTech Connect

    Fischer, W.; Luo, Y.; Abreu, N.; Calaga, R.; Montag, C.; Robert-Demolaize, G.; Dorda, U.; Koutchouk, J.-P.; Sterbini, G.; Zimmermann, F.; Kim, H.-J.; Sen, T.; Shiltsev, V.; Valishev, A.; Qiang, J.; Kabel, A.

    2009-01-12

    Long-range as well as head-on beam-beam effects are expected to limit the LHC performance with design parameters. They are also important consideration for the LHC upgrades. To mitigate long-range effects, current carrying wires parallel to the beam were proposed. Two such wires are installed in RHIC where they allow studying the effect of strong long-range beam-beam effects, as well as the compensation of a single long-range interaction. The tests provide benchmark data for simulations and analytical treatments. Electron lenses were proposed for both RHIC and the LHC to reduce the head-on beam-beam effect. We present the experimental long-range beam-beam program at RHIC and report on head-on compensations studies based on simulations.

  14. Results and applications of a space suit range-of-motion study

    NASA Technical Reports Server (NTRS)

    Reinhardt, AL

    1989-01-01

    The range of motion of space suits has traditionally been described using limited 2-D mapping of limb, torso, or arm movements performed in front of an orthogonal grid. A new technique for recovering extra-vehicular (EVA) space suit range-of-motion data during underwater testing was described in a paper presented by the author at the 1988 conference. The new technique uses digitized data which is automatically acquired from video images of the subject. Three-dimensional trajectories are recovered from these data, and can be displayed using 2-D computer graphics. Results of using this technique for the current shuttle EVA suit during underwater simulated weightlessness testing are discussed. Application of the data for use in animating anthropometric computer models is highlighted.

  15. A comparative study of optimum and suboptimum direct-detection laser ranging receivers

    NASA Technical Reports Server (NTRS)

    Abshire, J. B.

    1978-01-01

    A summary of previously proposed receiver strategies for direct-detection laser ranging receivers is presented. Computer simulations are used to compare performance of candidate implementation strategies in the 1- to 100-photoelectron region. Under the condition of no background radiation, the maximum-likelihood and minimum mean-square error estimators were found to give the same performance for both bell-shaped and rectangular optical-pulse shapes. For signal energies greater than 100 photoelectrons, the root-mean-square range error is shown to decrease as Q to the -1/2 power for bell-shaped pulses and Q to the -1 power for rectangular pulses, where Q represents the average pulse energy. Of several receiver implementations presented, the matched-filter peak detector was found to be preferable. A similar configuration, using a constant-fraction discriminator, exhibited a signal-level dependent time bias.

  16. A formalism for studying long-range correlations in many-alphabets sequences

    NASA Astrophysics Data System (ADS)

    Narasimhan, S. L.; Nathan, Joseph A.; Krishna, P. S. R.; Murthy, K. P. N.

    2006-07-01

    We formulate a mean-field-like theory of long-range correlated L-alphabets sequences, which are actually systems with (L-1) independent parameters. Depending on the values of these parameters, the variance on the average number of any given symbol in the sequence shows a linear or a superlinear dependence on the total length of the sequence. We present exact solution to the four-alphabets and three-alphabets sequences. We also demonstrate that a mapping of the given sequence into a smaller alphabets sequence (namely, a coarse-graining process) does not necessarily imply that long-range correlations found in the latter would correspond to those of the former.

  17. Trypanosoma rangeli: a new perspective for studying the modulation of immune reactions of Rhodnius prolixus

    PubMed Central

    Garcia, Eloi S; Castro, Daniele P; Figueiredo, Marcela B; Genta, Fernando A; Azambuja, Patrícia

    2009-01-01

    Insects are exposed to a wide range of microorganisms (bacteria, fungi, parasites and viruses) and have interconnected powerful immune reactions. Although insects lack an acquired immune system they have well-developed innate immune defences that allow a general and rapid response to infectious agents. Over the last few decades we have observed a dramatic increase in the knowledge of insect innate immunity, which relies on both humoral and cellular responses. However, innate reactions to natural insect pathogens and insect-transmitted pathogens, such as parasites, still remain poorly understood. In this review, we briefly introduce the general immune system of insects and highlight our current knowledge of these reactions focusing on the interactions of Trypanosoma rangeli with Rhodnius prolixus, an important model for innate immunity investigation. PMID:19615044

  18. Short-Range Structure of Clouds Studied by High Resolution Photography From the Surface

    NASA Astrophysics Data System (ADS)

    Schwartz, S. E.; Huang, D.; Vladutescu, D. V.

    2015-12-01

    Clouds exhibit structures at a wide range of length scales. Passive radiometry from satellite shows structure on scales of tens to thousands of kilometers, but there is much structure at short spatial scales not resolved by satellite imagery. Here we use a commercial camera having high spatial resolution (~20 μrad) and high dynamic range (16 bits in each of three color channels) in narrow field-of-view (20 mrad, 110 mrad), zenith-looking mode from the surface, to examine clouds at the scale of centimeters to a few hundred meters, focusing on non-precipitating single-layer clouds during daytime. Up-looking photography of clouds from the surface affords the further advantage, relative to satellite imagery, of black background (space) with contributions to radiance only from blue sky (Rayleigh scattering), aerosols, and clouds, permitting reconstruction of observed radiance by radiation transfer modeling. Contrast between cloudy and cloud-free sky is enhanced in Red/(Red + Blue), RRB, image Figure 1, but no unique value of RRB distinguishes a pixel as cloud vs. cloud-free. Short-range variability is characterized by the autocorrelation length scale, which is not uncommonly as short as a few meters; longer range variability, such as cloud characteristic size, separation distance, and cloud spatial organization, is also characterized. Scene reconstruction yields the 2D distribution of cloud optical depth; spatial inhomogeneity is attributed mainly to horizontal variation in vertical motion of the air and resultant condensation or evaporation associated with upward or downward motion, respectively. Alternative approaches to calculation of the radiative influence of such clouds from the autocorrelation structure of the cloud field are examined. Figure 1. RGB image of zenith sky at New York City, May 22, 2015, (field of view 21 mrad corresponding to 56 m at cloud altitude 2.6 km) showing broken single-layer cloud; corresponding RRB image; and autocorrelation of RRB image.

  19. Studies for determining the optimum propulsion system characteristics for use in a long range transport aircraft

    NASA Technical Reports Server (NTRS)

    Brines, G. L.

    1972-01-01

    A comprehensive evaluation of propulsion systems for the next generation of near-sonic long range transport aircraft indicates that socially responsive noise and emission goals can be achieved within the probable limits of acceptable airplane performance and economics. Technology advances needed in the 1975-1985 time period to support the development of these propulsion systems are identified and discussed. The single most significant result is the low noise, high performance potential of a low tip speed, spaced, two-stage fan.

  20. Long-range maintenance planning: A case study of working system

    SciTech Connect

    Flanigan, M.J.

    1991-10-01

    This paper addresses the development of the Lawrence Livermore National Laboratory (LLNL) Maintenance Planning System (MPS). The pitfalls encountered and overcome, and future expansion plans. The MPS provides the ability to develop and track long-range programs, i.e., conversion of chlorofluorocarbon (CFC) equipment to hydrochlorofluorocaron (HCFC), roofing, roads, etc., in addition to providing invaluable information and data for current year budget justification.

  1. Excessive crying at 3 months of age and behavioural problems at 4 years age: a prospective cohort study

    PubMed Central

    Santos, Iná S; Matijasevich, Alicia; Capilheira, Marcelo F; Anselmi, Luciana; Barros, Fernando C

    2015-01-01

    Background Excessive crying in early infancy has been associated with behavioural problems among preschool children from high income countries but studies in low income and middle income countries are scarce. Methods The 2004 Pelotas Birth Cohort is a population-based study planned to enrol all live births occurring in Pelotas that year and comprises 4231 children who so far have been followed up at 3, 12, 24, 48 and 72 months of age. Several familial, maternal and child characteristics were gathered in every follow-up. At the 3-month follow-up, infants whose mothers perceived them as crying more than others of the same age were classified as ‘crying babies’. Child behavioural problems were assessed through the Child Behavior Checklist (CBCL) applied to the mother at the 48-month follow-up. Crude and adjusted ORs with 95% CIs were calculated by logistic regression. Results Prevalence of excessive crying at 3 months was 11.9% (10.9% to 13.0%). Among children with excessive crying at 3 months the proportion in the clinical range for CBCL total, internalising and externalising problems at 4 years of age was 31.2%, 12.9% and 37.5%, respectively, against 20.6%, 6.8% and 29.6%, respectively, among non-crying babies. After controlling for confounders crying babies presented increased risk of being in clinical range of CBCL total (OR=1.34; 1.03 to 1.74), internalising (OR=1.55; 1.09 to 2.21) and externalising problems (OR=1.29; 1.01 to 1.64) than infants without excessive crying. Conclusions Excessive crying in early infancy may represent one important risk factor for developing behavioural problems in later phases of early childhood. PMID:25700531

  2. The Rush Memory and Aging Project: study design and baseline characteristics of the study cohort.

    PubMed

    Bennett, David A; Schneider, Julie A; Buchman, Aron S; Mendes de Leon, Carlos; Bienias, Julia L; Wilson, Robert S

    2005-01-01

    The long-term objective of the Rush Memory and Aging Project is to identify the postmortem indices linking genetic and environmental risk factors to the development of Alzheimer's disease (AD). The overall study design involves a detailed assessment of risk factors for AD in older persons without known dementia who agree to annual clinical evaluation and organ donation at the time of death. In contrast to other clinical-pathologic studies which are conducted on special populations, the Rush Memory and Aging Project enrolled a cohort with much greater diversity in terms of educational attainment, in addition to gender, race, and ethnicity. From September of 1997 through April of 2005, more than 1,000 older persons without known dementia from more than 30 residential facilities across the Chicago metropolitan area agreed to participate. Their mean age was 81 years, about a third had 12 or fewer years of education, a third were men, and about 10% were members of a racial or ethnic minority group. More than 950 already have completed their baseline clinical evaluation.

  3. Longitudinal selectivity in aging populations: separating mortality-associated versus experimental components in the Berlin Aging Study (BASE).

    PubMed

    Lindenberger, Ulman; Singer, Tania; Baltes, Paul B

    2002-11-01

    The authors examined 3.7-year selectivity in the Berlin Aging Study by comparing the T1 parent sample (N = 516) with the T3 sample (N = 206). Selectivity was partitioned into a mortality-associated component, reflecting the degree to which individuals still alive at T3 (T3 survivors, N = 313) differ from the T1 parent sample (N = 516) from which they originated, and an experimental component, reflecting the degree to which the T3 sample (N = 206) differed from T3 survivors (N = 313). Across 48 variables representing medical, sensorimotor, cognitive, personality-related, and socioeconomic domains, the mortality-associated component accounted for 64% of total selectivity, and the experimental component for 36% (0.18 vs 0.10 SD units; t = 7.20, p <.01). Except for age and intelligence, experimental selectivity effects regarding means and prevalence rates were generally small. Partitioning selectivity into mortality-associated and experimental components is a useful tool in the longitudinal study of aging populations.

  4. Aging Studies of 2nd Generation BaBar RPCs

    SciTech Connect

    Band, H.R.; /SLAC

    2007-09-25

    The BaBar detector, operating at the PEPII B factory of the Stanford Linear Accelerator Center (SLAC), installed over 200 2nd generation Resistive Plate Chambers (RPCs) in 2002. The streamer rates produced by backgrounds and signals from normal BaBar running vary considerably (0.1- >20 Hz/cm2) depending on the layer and position of the chambers, thus providing a broad spectrum test of RPC performance and aging. The lowest rate chambers have performed very well with stable efficiencies averaging 95%. Other chambers had rate-dependant inefficiencies due to Bakelite drying which were reversed by the introduction of humidified gases. RPC inefficiencies in the highest rate regions of the higher rate chambers have been observed and also found to be rate dependant. The inefficient regions grow with time and have not yet been reduced by operation with humidified input gas. Three of these chambers were converted to avalanche mode operation and display significantly improved efficiencies. The rate of production of HF in the RPC exhaust gases was measured in avalanche and streamer mode RPCs and found to be comparable despite the lower current of the avalanche mode RPCs.

  5. No Further Action Decision Under CERCLA, Fort Devens Study Area 28 Waste Explosives Detonation Range (Training Area 14)

    DTIC Science & Technology

    1994-01-01

    Environmental Response, Compensation and Lability Act ( CERCLA ) as amended by the Superfund Amendments and Reauthorization Act. An Enhanced Preliminary...til3i NO FURT ACTION DECISION UNDER CERCLA FORT DEVENS STUDY AREA 28 WASTE EXPLOSIVES DETONATION RANGE (TRAINING AREA 14) DATA ITEM A009...UNDER CERCLA STUDY AREA 28 WASTE EXPLOSIVES DETONATION RANGE (TRAINING AREA 14) FORT DEVENS, MASSACHUSETTS Prepared for: U.S. Army Environmental

  6. A controlled study of suicide in middle-aged and older people: personality traits, age, and psychiatric disorders.

    PubMed

    Draper, Brian; Kõlves, Kairi; De Leo, Diego; Snowdon, John

    2014-04-01

    Personality traits were examined using the NEO Five-Factor Inventory-Revised in an Australian psychological autopsy study involving 259 suicide deaths and 181 sudden death controls aged 35 years and over. Interviews included the Structured Clinical Interview for DSM-IV to determine the presence of psychiatric disorder. Personality traits of suicide deaths differed significantly from those of controls, scoring higher in the Neuroticism and Openness to Experience domains and lower on the Agreeableness and Extraversion domains. These findings varied with the presence of psychiatric disorder and by age. High Neuroticism scores were the most consistent finding in people who died by suicide, although these scores decreased in older suicides.

  7. The Walnuts and Healthy Aging Study (WAHA): Protocol for a Nutritional Intervention Trial with Walnuts on Brain Aging.

    PubMed

    Rajaram, Sujatha; Valls-Pedret, Cinta; Cofán, Montserrat; Sabaté, Joan; Serra-Mir, Mercè; Pérez-Heras, Ana M; Arechiga, Adam; Casaroli-Marano, Ricardo P; Alforja, Socorro; Sala-Vila, Aleix; Doménech, Mónica; Roth, Irene; Freitas-Simoes, Tania M; Calvo, Carlos; López-Illamola, Anna; Haddad, Ella; Bitok, Edward; Kazzi, Natalie; Huey, Lynnley; Fan, Joseph; Ros, Emilio

    2016-01-01

    Introduction: An unwanted consequence of population aging is the growing number of elderly at risk of neurodegenerative disorders, including dementia and macular degeneration. As nutritional and behavioral changes can delay disease progression, we designed the Walnuts and Healthy Aging (WAHA) study, a two-center, randomized, 2-year clinical trial conducted in free-living, cognitively healthy elderly men and women. Our interest in exploring the role of walnuts in maintaining cognitive and retinal health is based on extensive evidence supporting their cardio-protective and vascular health effects, which are linked to bioactive components, such as n-3 fatty acids and polyphenols. Methods: The primary aim of WAHA is to examine the effects of ingesting walnuts daily for 2 years on cognitive function and retinal health, assessed with a battery of neuropsychological tests and optical coherence tomography, respectively. All participants followed their habitual diet, adding walnuts at 15% of energy (≈30-60 g/day) (walnut group) or abstaining from walnuts (control group). Secondary outcomes include changes in adiposity, blood pressure, and serum and urinary biomarkers in all participants and brain magnetic resonance imaging in a subset. Results: From May 2012 to May 2014, 708 participants (mean age 69 years, 68% women) were randomized. The study ended in May 2016 with a 90% retention rate. Discussion: The results of WAHA might provide high-level evidence of the benefit of regular walnut consumption in delaying the onset of age-related cognitive impairment and retinal pathology. The findings should translate into public health policy and sound recommendations to the general population (ClinicalTrials.gov identifier NCT01634841).

  8. The Walnuts and Healthy Aging Study (WAHA): Protocol for a Nutritional Intervention Trial with Walnuts on Brain Aging

    PubMed Central

    Rajaram, Sujatha; Valls-Pedret, Cinta; Cofán, Montserrat; Sabaté, Joan; Serra-Mir, Mercè; Pérez-Heras, Ana M.; Arechiga, Adam; Casaroli-Marano, Ricardo P.; Alforja, Socorro; Sala-Vila, Aleix; Doménech, Mónica; Roth, Irene; Freitas-Simoes, Tania M.; Calvo, Carlos; López-Illamola, Anna; Haddad, Ella; Bitok, Edward; Kazzi, Natalie; Huey, Lynnley; Fan, Joseph; Ros, Emilio

    2017-01-01

    Introduction: An unwanted consequence of population aging is the growing number of elderly at risk of neurodegenerative disorders, including dementia and macular degeneration. As nutritional and behavioral changes can delay disease progression, we designed the Walnuts and Healthy Aging (WAHA) study, a two-center, randomized, 2-year clinical trial conducted in free-living, cognitively healthy elderly men and women. Our interest in exploring the role of walnuts in maintaining cognitive and retinal health is based on extensive evidence supporting their cardio-protective and vascular health effects, which are linked to bioactive components, such as n-3 fatty acids and polyphenols. Methods: The primary aim of WAHA is to examine the effects of ingesting walnuts daily for 2 years on cognitive function and retinal health, assessed with a battery of neuropsychological tests and optical coherence tomography, respectively. All participants followed their habitual diet, adding walnuts at 15% of energy (≈30–60 g/day) (walnut group) or abstaining from walnuts (control group). Secondary outcomes include changes in adiposity, blood pressure, and serum and urinary biomarkers in all participants and brain magnetic resonance imaging in a subset. Results: From May 2012 to May 2014, 708 participants (mean age 69 years, 68% women) were randomized. The study ended in May 2016 with a 90% retention rate. Discussion: The results of WAHA might provide high-level evidence of the benefit of regular walnut consumption in delaying the onset of age-related cognitive impairment and retinal pathology. The findings should translate into public health policy and sound recommendations to the general population (ClinicalTrials.gov identifier NCT01634841). PMID:28119602

  9. Photometric and spectroscopic study of the intermediate-age open cluster NGC 2355

    NASA Astrophysics Data System (ADS)

    Donati, P.; Bragaglia, A.; Carretta, E.; D'Orazi, V.; Tosi, M.; Cusano, F.; Carini, R.

    2015-11-01

    In this paper we analyse the evolutionary status and properties of the old open cluster NGC 2355, located in the Galactic anticentre direction, as a part of the long-term programme Bologna Open Clusters Chemical Evolution. NGC 2355 was observed with the Large Binocular Camera at the Large Binocular Telescope using the Bessel B, V, and Ic filters. The cluster parameters have been obtained using the synthetic colour-magnitude diagram method, as done in other papers of this series. Additional spectroscopic observations with the Fibre-fed Echelle Spectrograph at the Nordic Optical Telescope of three giant stars were used to determine the chemical properties of the cluster. Our analysis shows that NGC 2355 has metallicity slightly less than solar, with [Fe/H]= -0.06 dex, age between 0.8 and 1 Gyr, reddening E(B - V) in the range 0.14-0.19 mag, and distance modulus (m - M)0 of about 11 mag. We also investigate the abundances of O, Na, Al, α, iron-peak, and neutron capture elements, showing that NGC 2355 falls within the abundance distribution of similar clusters (same age and metallicity). The Galactocentric distance of NGC 2355 places it at the border between two regimes of metallicity distribution; this makes it an important cluster for the study of the chemical properties and evolution of the disc.

  10. Performance of the CogState computerized battery in the Mayo Clinic Study on Aging

    PubMed Central

    Mielke, Michelle M.; Machulda, Mary M.; Hagen, Clinton E.; Edwards, Kelly K.; Roberts, Rosebud O.; Pankratz, V. Shane; Knopman, David S.; Jack, Clifford R.; Petersen, Ronald C.

    2015-01-01

    Background The feasibility and validity of brief computerized cognitive batteries at the population-level are unknown. Methods Non-demented participants (n = 1660, age 50–97) in the Mayo Clinic Study on Aging completed the computerized CogState battery and standard neuropsychological battery. The correlation between tests was examined and comparisons between CogState performance on the personal computer (PC) and iPad (n = 331), and in the Clinic vs. at home (n = 194), were assessed. Results We obtained valid data on >97% of participants on each test. Correlations between the CogState and neuropsychological tests ranged from −0.462 to 0.531. While absolute differences between the PC and iPad were small and participants preferred the iPad, performance on the PC was faster. Participants performed faster on Detection, One Card Learning, and One Back at home compared to the Clinic. Conclusions The computerized CogState battery, especially the iPad, was feasible, acceptable, and valid in the population. PMID:25858683

  11. Detecting falls with 3D range camera in ambient assisted living applications: a preliminary study.

    PubMed

    Leone, Alessandro; Diraco, Giovanni; Siciliano, Pietro

    2011-07-01

    In recent years several world-wide ambient assisted living (AAL) programs have been activated in order to improve the quality of life of older people, and to strengthen the industrial base through the use of information and communication technologies. An important issue is extending the time that older people can live in their home environment, by increasing their autonomy and helping them to carry out activities of daily living (ADLs). Research in the automatic detection of falls has received a lot of attention, with the object of enhancing safety, emergency response and independence of the elderly, at the same time comparing the social and economic costs related to fall accidents. In this work, an algorithmic framework to detect falls by using a 3D time-of-flight vision technology is presented. The proposed system presented complementary working requirements with respect to traditional worn and non-worn fall-detection devices. The vision system used a state-of-the-art 3D range camera for elderly movement measurement and detection of critical events, such as falls. The depth images provided by the active sensor allowed reliable segmentation and tracking of elderly movements, by using well-established imaging methods. Moreover, the range camera provided 3D metric information in all illumination conditions (even night vision), allowing the overcoming of some typical limitations of passive vision (shadows, camouflage, occlusions, brightness fluctuations, perspective ambiguity). A self-calibration algorithm guarantees different setup mountings of the range camera by non-technical users. A large dataset of simulated fall events and ADLs in real dwellings was collected and the proposed fall-detection system demonstrated high performance in terms of sensitivity and specificity.

  12. Lead and PAHs contamination of an old shooting range: A case study with a holistic approach.

    PubMed

    Rodríguez-Seijo, A; Cachada, A; Gavina, A; Duarte, A C; Vega, F A; Andrade, M L; Pereira, R

    2017-01-01

    Soil pollution at firing ranges is an issue of growing importance, due to the accumulation in soils of contaminants derived from ammunition and clay targets. The concentration of Pb and PAHs was determined in five soils of an abandoned shooting range in Galicia (northwest Spain), and an ecotoxicological characterization was performed in order to obtain an assessment of risks. Therefore, the retention capacity of soils was assessed using test organisms of different trophic levels, and the role of soils as habitat for soil invertebrates was assessed by reproduction tests and bioaccumulation assays with earthworms. The sum of 15 PAHs ranged between 38 and 360mgkg(-1), which exceed, together with Pb (160-720mgkg(-1)), the Galician generic reference value for urban and sporting field soils. Bioaccumulation in E. andrei showed contents up to 104,000μgPbkg(-1)dw, and up to 645μgPAHskg(-1)fw. High contents of Pb and PAHs in soil samples and in Eisenia andrei whole body, caused a reduction in the number of juveniles produced, whereas, Vibrio fischeri, Raphidocelis subcapitata and Daphnia magna displayed a slight toxic response to the soil elutriates tested. Therefore, the function of these soils to retain contaminants seemed not compromised, probably due to the high organic matter content and pH values, which are weakly acidic. The habitat function was affected, indicating that soil solution is not the only route of exposure to contaminants to E. andrei. The integration of chemical and ecotoxicological lines of evidence give rise to high risks values, restricting the use of these areas, and pointing for risks to surrounding ecosystems due to possible trophic transferences. The calculation of risks using the chemical and ecotoxicological data, required by Spanish legislation, could be a good approach to communicate with those responsible and/or involved in the management of contaminated sites.

  13. The Philosophy of Local Studies in the Interactive Age

    ERIC Educational Resources Information Center

    Reid, Peter H.; Macafee, Caroline

    2007-01-01

    The authors examine strategic priorities for local studies libraries in the context of the interactive Web. They examine the implications for access, investigations and the needs of different users. The philosophy that has previously guided local studies is articulated as a number of maxims, taking into account also social inclusion and lifelong…

  14. Aeromagnetic and interpretation map of the King Range and Chemise Mountain Instant Study Areas, Northern California

    USGS Publications Warehouse

    Griscom, Andrew

    1980-01-01

    The data for the aeromagnetic map (sheet 1) of the King Range and Chemise Mountain areas wre collected in 1978 and compiled at a scale of 1:62,500. Northeast-southwest traverses were spaced at 0.8-km intervals at an altitude for 300 m above the ground surface and 600 m above the ocean because of cliffs along the shore. The contour interval is 10 of or 50γ, depending on the steepness of local gradients in the Earth's magnetic field. A regional field of approximately 5.6 γ/km was removed from the data before contouring. 

  15. Application of Laser Ranging and VLBI Data to a Study of Plate Tectonic Driving Forces

    NASA Technical Reports Server (NTRS)

    Solomon, S. C.

    1980-01-01

    The conditions under which changes in plate driving or resistive forces associated with plate boundary earthquakes are measurable with laser ranging or very long base interferometry were investigated. Aspects of plate forces that can be characterized by such measurements were identified. Analytic solutions for two dimensional stress diffusion in a viscoelastic plate following earthquake faulting on a finite fault, finite element solutions for three dimensional stress diffusion in a viscoelastic Earth following earthquake faulting, and quantitative constraints from modeling of global intraplate stress on the magnitude of deviatoric stress in the lithosphere are among the topics discussed.

  16. Metabolic profiles of biological aging in American Indians: the Strong Heart Family Study.

    PubMed

    Zhao, Jinying; Zhu, Yun; Uppal, Karan; Tran, ViLinh T; Yu, Tianwei; Lin, Jue; Matsuguchi, Tet; Blackburn, Elizabeth; Jones, Dean; Lee, Elisa T; Howard, Barbara V

    2014-03-01

    Short telomere length, a marker of biological aging, has been associated with age-related metabolic disorders. Telomere attrition induces profound metabolic dysfunction in animal models, but no study has examined the metabolome of telomeric aging in human. Here we studied 423 apparently healthy American Indians participating in the Strong Family Heart Study. Leukocyte telomere length (LTL) was measured by qPCR. Metabolites in fasting plasma were detected by untargeted LC/MS. Associations of LTL with each metabolite and their combined effects were examined using generalized estimating equation adjusting for chronological age and other aging-related factors. Multiple testing was corrected using the q-value method (q<0.05). Of the 1,364 distinct m/z features detected, nineteen metabolites in the classes of glycerophosphoethanolamines, glycerophosphocholines, glycerolipids, bile acids, isoprenoids, fatty amides, or L-carnitine ester were significantly associated with LTL, independent of chronological age and other aging-related factors. Participants with longer (top tertile) and shorter (bottom tertile) LTL were clearly separated into distinct groups using a multi-marker score comprising of all these metabolites, suggesting that these newly detected metabolites could be novel metabolic markers of biological aging. This is the first study to interrogate the human metabolome of telomeric aging. Our results provide initial evidence for a metabolic control of LTL and may reveal previously undescribed new roles of various lipids in the aging process.

  17. Application of generalized Snoek's law over a finite frequency range: A case study

    NASA Astrophysics Data System (ADS)

    Rozanov, Konstantin N.; Koledintseva, Marina Y.

    2016-02-01

    Generalized Snoek's law proposed in an integral form by Acher and coauthors is a useful tool for investigation of high-frequency properties of magnetic materials. This integral law referred to as Acher's law allows for evaluating the ultimate performance of RF and microwave devices which employ magnetic materials. It may also be helpful in obtaining useful information on the structure and morphology of the materials. The key factor in practical application of Acher's law is an opportunity to employ either measured or calculated data available over a finite frequency range. The paper uses simple calculations to check the applicability of Acher's law in cases when the frequency range is limited and the magnetic loss peak is comparatively wide and has a distorted shape. The cases of large magnetic damping, pronounced skin effect, and inhomogeneity of the material are considered. It is shown that in most cases calculation of the integral through fitting of actual magnetic frequency dispersion by the Lorentzian dispersion law results in accurate estimations of the ultimate high-frequency performance of magnetic materials.

  18. Molecular diffusion measurement in lipid bilayers over wide concentration ranges: a comparative study.

    PubMed

    Guo, Lin; Har, Jia Yi; Sankaran, Jagadish; Hong, Yimian; Kannan, Balakrishnan; Wohland, Thorsten

    2008-04-04

    Molecular diffusion in biological membranes is a determining factor in cell signaling and cell function. In the past few decades, three main fluorescence spectroscopy techniques have emerged that are capable of measuring molecular diffusion in artificial and biological membranes at very different concentration ranges and spatial resolutions. The widely used methods of fluorescence recovery after photobleaching (FRAP) and single-particle tracking (SPT) can determine absolute diffusion coefficients at high (>100 microm(-2)) and very low surface concentrations (single-molecule level), respectively. Fluorescence correlation spectroscopy (FCS), on the other hand, is well-suited for the intermediate concentration range of about 0.1-100 microm(-2). However, FCS in general requires calibration with a standard dye of known diffusion coefficient, and yields only relative measurements with respect to the calibration. A variant of FCS, z-scan FCS, is calibration-free for membrane measurements, but requires several experiments at different well-controlled focusing positions. A recently established FCS method, electron-multiplying charge-coupled-device-based total internal reflection FCS (TIR-FCS), referred to here as imaging TIR-FCS (ITIR-FCS), is also independent of calibration standards, but to our knowledge no direct comparison between these different methods has been made. Herein, we seek to establish a comparison between FRAP, SPT, FCS, and ITIR-FCS by measuring the lateral diffusion coefficients in two model systems, namely, supported lipid bilayers and giant unilamellar vesicles.

  19. Biased diffusion in tubes of alternating diameter: Numerical study over a wide range of biasing force

    SciTech Connect

    Makhnovskii, Yurii A.; Berezhkovskii, Alexander M.; Antipov, Anatoly E.; Zitserman, Vladimir Yu.

    2015-11-07

    This paper is devoted to particle transport in a tube formed by alternating wide and narrow sections, in the presence of an external biasing force. The focus is on the effective transport coefficients—mobility and diffusivity, as functions of the biasing force and the geometric parameters of the tube. Dependences of the effective mobility and diffusivity on the tube geometric parameters are known in the limiting cases of no bias and strong bias. The approximations used to obtain these results are inapplicable at intermediate values of the biasing force. To bridge the two limits Brownian dynamics simulations were run to determine the transport coefficients at intermediate values of the force. The simulations were performed for a representative set of tube geometries over a wide range of the biasing force. They revealed that there is a range of the narrow section length, where the force dependence of the mobility has a maximum. In contrast, the diffusivity is a monotonically increasing function of the force. A simple formula is proposed, which reduces to the known dependences of the diffusivity on the tube geometric parameters in both limits of zero and strong bias. At intermediate values of the biasing force, the formula catches the diffusivity dependence on the narrow section length, if the radius of these sections is not too small.

  20. Exposure to any antenatal corticosteroids and outcomes in preterm infants by gestational age: prospective cohort study

    PubMed Central

    Travers, Colm P; Clark, Reese H; Spitzer, Alan R; Das, Abhik; Garite, Thomas J

    2017-01-01

    Objective To determine whether exposure to any antenatal corticosteroids is associated with a lower rate of death at each gestational age at which administration is currently recommended. Design Prospective cohort study. Settings 300 participating neonatal intensive care units of the Pediatrix Medical Group in the United States. Participants 117 941 infants 23 0/7 to 34 6/7 weeks’ gestational age born between 1 January 2009 and 31 December 2013. Exposure Any antenatal corticosteroids. Main outcomes measures Death or major hospital morbidities analyzed by gestational age and exposure to antenatal corticosteroids with models adjusted for birth weight, sex, mode of delivery, and multiple births. Results Infants exposed to antenatal corticosteroids (n=81 832) had a significantly lower rate of death before discharge at each gestation 29 weeks or less, 31 weeks, and 33-34 weeks compared with infants without exposure (range of adjusted odds ratios 0.32 to 0.55). The number needed to treat with antenatal corticosteroids to prevent one death before discharge increased from six at 23 and 24 weeks’ gestation to 798 at 34 weeks’ gestation. The rate of survival without major hospital morbidity was higher among infants exposed to antenatal corticosteroids at the lowest gestations. Infants exposed to antenatal corticosteroids had lower rates of severe intracranial hemorrhage or death, necrotizing enterocolitis stage 2 or above or death, and severe retinopathy of prematurity or death compared with infants without exposure at all gestations less than 30 weeks and most gestations for infants born at 30 weeks’ gestation or later. Conclusion Among infants born from 23 to 34 weeks’ gestation, antenatal exposure to corticosteroids compared with no exposure was associated with lower mortality and morbidity at most gestations. The effect size of exposure to antenatal corticosteroids on mortality seems to be larger in infants born at the lowest gestations. PMID

  1. When Anti-Aging Studies Meet Cancer Chemoprevention: Can Anti-Aging Agent Kill Two Birds with One Blow?

    PubMed

    Yokoyama, Noriko N; Denmon, Andria; Uchio, Edward M; Jordan, Mark; Mercola, Dan; Zi, Xiaolin

    2015-12-01

    Recent evidence has strongly supported that the rate of aging is controlled, at least to some extent, by evolutionarily conserved nutrient sensing pathways (e.g. the insulin/IGF-1-signaling, mTOR, AMPK, and sirtuins) from worms to humans. These pathways are also commonly involved in carcinogenesis and cancer metabolism. Agents (e.g. metformin, resveratrol, and Rhodiola) that target these nutrient sensing pathways often have both anti-aging and anti-cancer efficacy. These agents not only reprogram energy metabolism of malignant cells, but also target normal postmitotic cells by suppressing their conversion into senescent cells, which confers systematic metabolism benefits. These agents are fundamentally different from chemotherapy (e.g. paclitaxel and doxorubicin) or radiation therapy that causes molecular damage (e.g. DNA and protein damages) and thereby no selection resistance may be expected. By reviewing molecular mechanisms of action, epidemiological evidence, experimental data in tumor models, and early clinical study results, this review provides information supporting the promising use of agents with both anti-aging and anti-cancer efficacy for cancer chemoprevention.

  2. Doctoral Curriculum Studies in an Age of Shifting Boundaries.

    ERIC Educational Resources Information Center

    Ansaldo, Jim; Goodman, Jesse

    2002-01-01

    Describes faculty and student experiences involving efforts to restructure the curriculum-studies doctoral program at Indiana University in light of shifting and ambiguous field boundaries. (Contains 26 references.) ((PKP)

  3. Programs for Parents and Their Children in the Prenatal-Through-Three Age Range: A Child and Family Resource Program Guidance Paper.

    ERIC Educational Resources Information Center

    Dingle Associates, Inc., Washington, DC.

    This paper presents guidelines for family support programs prepared for the Child and Family Resource Program (CFRP) and other child development programs. Section I contains a brief description of the CFRP philosophy, a listing of CFRP's long range goals, detailed objectives/minimum performance standards for implementing each of these goals, and…

  4. Self-perceptions of aging predict mortality and change with approaching death: 16-year longitudinal results from the Berlin Aging Study.

    PubMed

    Kotter-Grühn, Dana; Kleinspehn-Ammerlahn, Anna; Gerstorf, Denis; Smith, Jacqui

    2009-09-01

    Satisfaction with one's own aging and feeling young are indicators of positive well-being in late life. Using 16-year longitudinal data from participants of the Berlin Aging Study (P. B. Baltes & K. U. Mayer, 1999; N = 439; 70- to 100-year-olds), the authors examined whether and how these self-perceptions of aging change with age and how such changes relate to distance from death. Extending previous studies, they found that it is not only higher aging satisfaction and younger subjective age but also more favorable change patterns (e.g., less decline in aging satisfaction) that are uniquely associated with lower mortality hazards. These effects are robust after controls for objective measures such as age, gender, socioeconomic status, diagnosis of dementia, or number of illnesses. As individuals approach death, they become less satisfied with their aging and report feeling older. For aging satisfaction, mortality-related decline is much steeper than age-related decline, whereas change in subjective age is best characterized as an age-related process. The authors discuss how self-perceptions of aging are embedded in mechanisms underlying pathways of dying late in life.

  5. The dynamic range of biologic functions and variation of many environmental cues may be declining in the modern age: implications for diseases and therapeutics.

    PubMed

    Yun, Anthony J; Bazar, Kimberly A; Gerber, Anthony; Lee, Patrick Y; Daniel, Stephanie M

    2005-01-01

    We hypothesize that declining dynamic range and variation of environmental cues may contribute to health dysfunctions, and that judicious expansion of biologic dynamic ranges may be beneficial. Three disparate examples involving the endocrine, autonomic, and musculoskeletal systems are discussed. Daytime sheltering, optical shading, and nighttime use of artificial light may reduce circadian luminal variation. The resulting melatonin alterations may contribute to systemic dysfunctions. Loss of temporal variation of other hormones may contribute to biologic dysfunctions, especially those involving the hypothalamic-pituitary axis. Reduced variation of physical exertion, environmental stressors, and thermal gradients that characterize modern lifestyles may reduce the autonomic dynamic range resulting in lowered heart rate variability and a myriad of systemic dysfunctions. The health benefits of activities such as exercise, meditation, acupuncture, coitus, and laughter may operate through increasing autonomic variability. Reduced physical exertion also accounts for declining dynamic range of musculoskeletal function. The resulting muscle atrophy, fat infiltration, and sarcomere shortening may not only have deleterious local effects, but may also be involved in systemic metabolic dysfunctions such as insulin resistance. The extent to which our endogenous systems rely on environmental variation for self-tuning and the impact that under-utilization of compensatory mechanisms has on biologic function are not well understood. Modern therapeutic approaches generally result in reversion to the mean of physiologic functions and may buffer against variation. For example, beta-blockers are given to reduce adrenergic excess, insulin to treat insulin insufficiency, serotonin-reuptake inhibitors for depression, and refractive lenses for myopia. By undermining the demand for native compensatory functions, such therapeutic strategies may actually impair future ability to respond to

  6. Dental cementum in age estimation: a polarized light and stereomicroscopic study.

    PubMed

    Kasetty, Sowmya; Rammanohar, M; Raju Ragavendra, T

    2010-05-01

    Dental hard tissues are good candidates for age estimation as they are less destructive and procedures to determine age can be easily performed. Although cementum annulations and cementum thickness are important parameters in this regard, they are seldom used. This study was undertaken to review the methods, difficulties in execution of techniques, and accuracy of cementum thickness and annulations in estimating the age. Unstained and stained ground sections of tooth were used to measure cemental thickness and count cemental annulations based on which age was estimated and was compared with known age. Although there was positive relation between cemental thickness and annulations with age, only in 1-1.5% of cases, age could be predicted with accuracy.

  7. [Comparative studies of particle distribution range of aerosol cromolyn sodium generated by MDI systems].

    PubMed

    Gradoń, L; Sosnowski, T R

    1999-05-01

    Particles size distribution of the sodium cromoglycate preparations: CROPOZ PLUS and CROMOGEN EB generated with MDI and for under-pressure releasing methods were measured. Results of measurements indicate a significant repeatability of each sample properties. An average contribution of mass of the respirable fraction for both aerosolized pharmaceuticals is in the range of 40% of the generated dose. CROMOGEN EB with optimizer (spacer) gives a higher contribution of the respirable fraction--up to 50% of dose, with simultaneous lower value of the released mass of aerosol. Particles size distribution of CROPOZ PLUS within a respirable fraction indicates an efficient penetration and deposition of particles in the upper, central and peripheral parts of tracheobronchial tree (TB). High contribution of submicron particles of CROMOGEN EB with optimizer gives efficient penetration and deposition of these particles in the lungs.

  8. A Study of LoRa: Long Range & Low Power Networks for the Internet of Things

    PubMed Central

    Augustin, Aloÿs; Yi, Jiazi; Clausen, Thomas; Townsley, William Mark

    2016-01-01

    LoRa is a long-range, low-power, low-bitrate, wireless telecommunications system, promoted as an infrastructure solution for the Internet of Things: end-devices use LoRa across a single wireless hop to communicate to gateway(s), connected to the Internet and which act as transparent bridges and relay messages between these end-devices and a central network server. This paper provides an overview of LoRa and an in-depth analysis of its functional components. The physical and data link layer performance is evaluated by field tests and simulations. Based on the analysis and evaluations, some possible solutions for performance enhancements are proposed. PMID:27618064

  9. A study of engine variable geometry systems for an advanced high subsonic long range commercial aircraft

    NASA Technical Reports Server (NTRS)

    Compagnon, M. A.

    1973-01-01

    Several variable geometry high Mach inlet concepts, aimed at meeting a system noise objective of 15 EPNdB below FAR part 36, for a long range, Mach 0.9 advanced commercial transport are assessed and compared to a fixed geometry inlet with multiple splitters. The effects of a variable exhaust nozzle (mixed exhaust engine) on noise, inlet geometry requirements, and economics are also presented. The best variable geometry inlet configuration identified is a variable cowl design which relies on a high throat Mach number for additional inlet noise suppression only at takeoff, and depends entirely on inlet wall treatment for noise suppression at approach power. Relative economic penalties as a function of noise level are also presented.

  10. Experimental study of attenuation and dispersion over a broad frequency range: 1. The apparatus

    NASA Astrophysics Data System (ADS)

    Takei, Yasuko; Fujisawa, Kazuhiro; McCarthy, Christine

    2011-09-01

    We have developed a new experimental method to investigate the anelasticity of a polycrystalline solid at high homologous temperature (T/Tm = 0.6-0.7). By using a rock analogue (borneol polycrystals) and a partially molten rock analogue (borneol + melt) having low melting and eutectic temperatures (Tm = 204.5°C, Te = 43°C), respectively, testing high homologous temperature can occur near room temperature. An apparatus is described for cyclic compressive, Young's modulus type attenuation experiments over a wide range of frequencies (10-10-4 Hz) and at small strain amplitudes (10-6-10-5). Creep tests to measure steady state viscosity can also be performed. Details of the apparatus, including its piezoelectric actuator, dual laser displacement meters and trio of load cells, are discussed. Attenuation spectra and modulus dispersion measured for aluminum, acrylic plastic, and a rock analogue are presented to illustrate the accuracy of the method.

  11. A range muon tomography performance study for the detection of explosives

    SciTech Connect

    Cuellar, Leticia; Borozdin, Konstantin N; Chung, Andrew; Nicolas, Hengartner W; Morris, Christopher; Schultz, Larry J; Reimus, Nathaniel P; Bacon, Jeffrey D; Vogan - Mc Neil, Wendy

    2010-01-01

    Soft cosmic ray tomography has been shown to successfully discriminate materials with various density levels due to their ability to deeply penetrate matter, allowing sensitivity to atomic number, radiation length and density. Because the multiple muon scattering signal from high Z-materials is very strong, the technology is well suited to the detection of the illicit transportation of special and radiological nuclear materials. In addition, a recent detection technique based on measuring the lower energy particles that do not traverse the material (range radiography), allows to discriminate low and medium Z-materials. This is shown in [4] using Monte Carlo simulations. More recently, using a mini muon tracker developed at Los Alamos National Laboratory, we performed various experiments to try out the radiation length technology. This paper presents the results from real experiments and evaluates the likelihood that soft cosmic ray tomography may be applied to detect high-explosives.

  12. A Study of LoRa: Long Range & Low Power Networks for the Internet of Things.

    PubMed

    Augustin, Aloÿs; Yi, Jiazi; Clausen, Thomas; Townsley, William Mark

    2016-09-09

    LoRa is a long-range, low-power, low-bitrate, wireless telecommunications system, promoted as an infrastructure solution for the Internet of Things: end-devices use LoRa across a single wireless hop to communicate to gateway(s), connected to the Internet and which act as transparent bridges and relay messages between these end-devices and a central network server. This paper provides an overview of LoRa and an in-depth analysis of its functional components. The physical and data link layer performance is evaluated by field tests and simulations. Based on the analysis and evaluations, some possible solutions for performance enhancements are proposed.

  13. DIETARY CARBOHYDRATE AND PROGRESSION OF AGE-RELATED MACULAR DEGENERATION, A PROSPECTIVE STUDY FROM THE AGE-RELATED EYE DISEASE STUDY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background Cross-sectional studies indicate that diets that provide a higher dietary glycemic index (dGI) are associated with increased risk of age-related macular degeneration (AMD). No prospective studies have addressed this issue. Methods dGI was calculated as the weighted average of GIs