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Sample records for aging study nas

  1. Greenhouse policy study from NAS

    NASA Astrophysics Data System (ADS)

    Maggs, William Ward

    The National Academy of Sciences will produce a study for the Environmental Protection Agency on policy responses to global warming. The report is due out before the end of 1990.Dan J. Evans, former U.S. Senator and former Governor of Washington, will chair a panel of the Commission on Science, Engineering, and Public Policy, a body of the councils of the NAS, National Academy of Engineering, and Institute of Medicine. Evans is a registered civil engineer and previously chaired the Pacific Northwest Electric Power and Conservation Planning Council.The 13-person panel includes AGU members Stephen Schneider of the National Center for Atmospheric Research and Robert Frosch, Vice President of Research Laboratores at General Motors Corp., Jessica Mathews, Vice President of the World Resources Institute, and Sir Crispin Tickell, the United Kingdom's Ambassador to the United Nations.

  2. Study of GaInNAs Epilayers Using Optical Methods

    NASA Astrophysics Data System (ADS)

    Tsai, Yutsung

    Photovoltaic devices that convert sun's energy into electricity have the potential to influence energy needs on a global scale. A major limitation of single junction solar cells is that only photons with energy slightly above the bandgap are absorbed efficiently. One of the methods is to split the energy of the incoming spectrum into multiple bands each of which is absorbed separately for more efficient collection. That is why multijunction solar cells formed from III-V compound semiconductors are the highest efficiency photovoltaic devices today. To achieve this goal, researchers stack a number of junctions made of different materials with the highest gap material at the top and the lowest at the bottom since each material is transparent to photons with energy smaller than its bandgap. Kurtz [1] predicted an improvement in the performance of multijunction solar cells if a fourth material with bandgap in the 1.0eV-1.05eV range is included between the GaAs (bandgap = 1.42 eV) and Ge (bandgap = 0.67 eV) in the solar cell. In order for this fourth material to be easily incorporated into the GaInP/ GaAs/Ge triple junction device, it must also be lattice matched to germanium. Since it is preferred to grow multijunction solar cells monolithically lattice matching is required making the options for the 1 eV material rather limited. The most promising material for the fourth junction is currently GaInNAs. This is the reason why this thesis concentrates on the study of this material. In this thesis, we have conducted PL, optical pumping, magneto-PL, reflectance and transmission spectroscopic studies of undoped and p-type doped GaInNAs epilayers. The objective of these studies is to investigate the following phenomena in our samples: (a) Localized excitons and free excitons at low temperatures in GaInNAs epilayers: The exciton localization at low temperatures in undoped GaInNAs epilayers results in the S-shape of the PL peaks versus temperature plot. On the other hand, the

  3. A Programming Model Performance Study Using the NAS Parallel Benchmarks

    DOE PAGES

    Shan, Hongzhang; Blagojević, Filip; Min, Seung-Jai; ...

    2010-01-01

    Harnessing the power of multicore platforms is challenging due to the additional levels of parallelism present. In this paper we use the NAS Parallel Benchmarks to study three programming models, MPI, OpenMP and PGAS to understand their performance and memory usage characteristics on current multicore architectures. To understand these characteristics we use the Integrated Performance Monitoring tool and other ways to measure communication versus computation time, as well as the fraction of the run time spent in OpenMP. The benchmarks are run on two different Cray XT5 systems and an Infiniband cluster. Our results show that in general the threemore » programming models exhibit very similar performance characteristics. In a few cases, OpenMP is significantly faster because it explicitly avoids communication. For these particular cases, we were able to re-write the UPC versions and achieve equal performance to OpenMP. Using OpenMP was also the most advantageous in terms of memory usage. Also we compare performance differences between the two Cray systems, which have quad-core and hex-core processors. We show that at scale the performance is almost always slower on the hex-core system because of increased contention for network resources.« less

  4. 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.

  5. Feasibility study for a secondary Na/S battery

    NASA Technical Reports Server (NTRS)

    Abraham, K. M.; Schiff, R.; Brummer, S. B.

    1979-01-01

    The feasibility of a moderate temperature Na battery was studied. This battery is to operate at a temperature in the range of 100-150 C. Two kinds of cathode were investigated: (1) a soluble S cathode consisting of a solution of Na2Sn in an organic solvent and (2) an insoluble S cathode consisting of a transition metal dichalcogenide in contact with a Na(+)ion conducting electrolyte. Four amide solvents, dimethyl acetamide, diethyl acetamide, N-methyl acetamide and acetamide, were investigated as possible solvents for the soluble S cathode. Results of stability and electrochemical studies using these solvents are presented. The dialkyl substituted amides were found to be superior. Although the alcohol 1,3-cyclohexanediol was found to be stable in the presence of Na2Sn at 130 C, its Na2Sn solutions did not appear to have suitable electrochemical properties.

  6. 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.

  7. 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).

  8. The study of exoplanets and protoplanetary discs in the Main astronomical observatory of NAS of Ukraine

    NASA Astrophysics Data System (ADS)

    Kuznyetsova, Yu. G.; Krushevska, V. N.; Zakhozhay, O. V.; Matsiaka, O. M.; Vidmachenko, A. P.; Shliakhetskaya, Ya. O.; Andreev, M. V.; Romaniuk, Ya. O.

    2016-10-01

    Long-term spectral and photometric observations of transit and nontransit exoplanet systems are carried out in MAO NAS of Ukraine. On the base of obtained data we study the influence of exoplanets on chromospherical activity of the host stars, model the light curves, calculate exoplanet system's parameters and search planets in eclipsing binary star's systems. In the field of protoplanetary disc researches it was developed a new algorithm for calculation of the energy distribution in spectra of systems containing a spherical central source and a surrounding protoplanetary disc.

  9. Deep-level study of Ga(In)P(NAs) alloys grown on Si substrates

    NASA Astrophysics Data System (ADS)

    Baranov, A. I.; Kleider, J. P.; Gudovskikh, A. S.; Darga, A.; Nikitina, E. V.; Egorov, A. Yu

    2016-08-01

    Defect properties of Ga(In)P(NAs) layers with different composition were studied by admittance spectroscopy. For nitrogen content layers the defect level with energy of 0.44-0.47 eV, which related to nitrogen incorporation into GaP, was observed. Its concentration is lower for GaPNAs layers compared to GaPN/InP due to better compensation by arsenic than by indium in lattice of GaP. Other defect level with energy of 0.30 eV was detected in GaPAs and GaPN/InP layers. Likely, the both observed defects in GaPAs and GaPN/InP have the same nature.

  10. First-principles study on structure stabilities of α-S and Na-S battery systems

    NASA Astrophysics Data System (ADS)

    Momida, Hiroyoshi; Oguchi, Tamio

    2014-03-01

    To understand microscopic mechanisms of charge and discharge reactions in Na-S batteries, there has been increasing needs to study fundamental atomic and electronic structures of elemental S as well as that of Na-S phases. The most stable form of S is known to be an orthorhombic α-S crystal at ambient temperature and pressure, and α-S consists of puckered S8 rings which crystallize in space group Fddd . In this study, the crystal structure of α-S is examined by using first-principles calculations with and without the van der Waals interaction corrections of Grimme's method, and results clearly show that the van der Waals interactions between the S8 rings have crucial roles on cohesion of α-S. We also study structure stabilities of Na2S, NaS, NaS2, and Na2S5 phases with reported crystal structures. Using calculated total energies of the crystal structure models, we estimate discharge voltages assuming discharge reactions from 2Na+ xS -->Na2Sx, and discharge reactions in Na/S battery systems are discussed by comparing with experimental results. This work was partially supported by Elements Strategy Initiative for Catalysts and Batteries (ESICB) of Ministry of Education, Culture, Sports, Science, and Technology (MEXT), Japan.

  11. [Study on the Application of NAS-Based Algorithm in the NIR Model Optimization].

    PubMed

    Geng, Ying; Xiang, Bing-ren; He, Lan

    2015-10-01

    In this paper, net analysis signal (NAS)-based concept was introduced to the analysis of multi-component Ginkgo biloba leaf extracts. NAS algorithm was utilized for the preprocessing of spectra, and NAS-based two-dimensional correlation analysis was used for the optimization of NIR model building. Simultaneous quantitative models for three flavonol aglycones: quercetin, keampferol and isorhamnetin were established respectively. The NAS vectors calculated using two algorithms introduced from Lorber and Goicoechea and Olivieri (HLA/GO) were applied in the development of calibration models, the reconstructed spectra were used as input of PLS modeling. For the first time, NAS-based two-dimensional correlation spectroscopy was used for wave number selection. The regions appeared in the main diagonal were selected as useful regions for model building. The results implied that two NAS-based preprocessing methods were successfully used for the analysis of quercetin, keampferol and isorhamnetin with a decrease of factor number and an improvement of model robustness. NAS-based algorithm was proven to be a useful tool for the preprocessing of spectra and for optimization of model calibration. The above research showed a practical application value for the NIRS in the analysis of complex multi-component petrochemical medicine with unknown interference.

  12. Photoluminescence study of Be acceptors in GaInNAs epilayers

    NASA Astrophysics Data System (ADS)

    Tsai, Y.; Barman, B.; Scrace, T.; Petrou, A.; Fukuda, M.; Sellers, I. R.; Leroux, M.; Khalfioui, M. A.

    2014-03-01

    We have studied the photoluminescence (PL) spectra from MBE grown GaInNAs epilayers doped p-type with Beryllium acceptors. The measurements were carried out in the 5 K - 70 K temperature range and in magnetic fields (B) up to 7 tesla. The PL spectra contain two features at T = 5 K: The exciton at 1093 meV and a second broader feature at 1058 meV. The intensity of this feature decreases with increasing temperature and disappears completely by 70K while the excitonic feature persists. The emission at 1058meV is identified as the conduction band to Beryllium acceptor transition. If we take into account the binding energy of the exciton [3] we get a value of 23 meV for the Beryllium acceptor binding energy. The acceptor related transition was studied as a function of magnetic field; the energy of this transition has a linear dependence on B with a slope of 055 meV/T. Research supported by Amethyst Research In. through the State of Oklahoma, ONAP program.

  13. MPI, HPF or OpenMP: A Study with the NAS Benchmarks

    NASA Technical Reports Server (NTRS)

    Jin, H.; Frumkin, M.; Hribar, M.; Waheed, A.; Yan, J.; Saini, Subhash (Technical Monitor)

    1999-01-01

    Porting applications to new high performance parallel and distributed platforms is a challenging task. Writing parallel code by hand is time consuming and costly, but this task can be simplified by high level languages and would even better be automated by parallelizing tools and compilers. The definition of HPF (High Performance Fortran, based on data parallel model) and OpenMP (based on shared memory parallel model) standards has offered great opportunity in this respect. Both provide simple and clear interfaces to language like FORTRAN and simplify many tedious tasks encountered in writing message passing programs. In our study, we implemented the parallel versions of the NAS Benchmarks with HPF and OpenMP directives. Comparison of their performance with the MPI implementation and pros and cons of different approaches will be discussed along with experience of using computer-aided tools to help parallelize these benchmarks. Based on the study, potentials of applying some of the techniques to realistic aerospace applications will be presented.

  14. MPI, HPF or OpenMP: A Study with the NAS Benchmarks

    NASA Technical Reports Server (NTRS)

    Jin, Hao-Qiang; Frumkin, Michael; Hribar, Michelle; Waheed, Abdul; Yan, Jerry; Saini, Subhash (Technical Monitor)

    1999-01-01

    Porting applications to new high performance parallel and distributed platforms is a challenging task. Writing parallel code by hand is time consuming and costly, but the task can be simplified by high level languages and would even better be automated by parallelizing tools and compilers. The definition of HPF (High Performance Fortran, based on data parallel model) and OpenMP (based on shared memory parallel model) standards has offered great opportunity in this respect. Both provide simple and clear interfaces to language like FORTRAN and simplify many tedious tasks encountered in writing message passing programs. In our study we implemented the parallel versions of the NAS Benchmarks with HPF and OpenMP directives. Comparison of their performance with the MPI implementation and pros and cons of different approaches will be discussed along with experience of using computer-aided tools to help parallelize these benchmarks. Based on the study,potentials of applying some of the techniques to realistic aerospace applications will be presented

  15. 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

  16. Photoluminescence and magnetophotoluminescence studies in GaInNAs/GaAs quantum wells

    NASA Astrophysics Data System (ADS)

    Segura, J.; Garro, N.; Cantarero, A.; Miguel-Sánchez, J.; Guzmán, A.; Hierro, A.

    2007-04-01

    We investigate the effects of electron and hole localization in the emission of a GaInNAs/GaAs single quantum well at low temperatures. Photoluminescence measurements varying the excitation density and under magnetic fields up to 14 T have been carried out. The results indicate that electrons are strongly localized in these systems due to small fluctuations in the nitrogen content of the quaternary alloy. The low linear diamagnetic shift of the emission points out the weakness of the Coulomb correlation between electrons and holes and suggests an additional partial localization of the holes.

  17. The NAS Computational Aerosciences Archive

    NASA Technical Reports Server (NTRS)

    Miceli, Kristina D.; Globus, Al; Lasinski, T. A. (Technical Monitor)

    1995-01-01

    performed by NAS staff members and collaborators. Visual results, which may be available in the form of images, animations, and/or visualization scripts, are generated by researchers with respect to a certain research project, depicting dataset features that were determined important by the investigating researcher. For example, script files for visualization systems (e.g. FAST, PLOT3D, AVS) are provided to create visualizations on the user's local workstation to elucidate the key points of the numerical study. Users can then interact with the data starting where the investigator left off. Datasets are intended to give researchers an opportunity to understand previous work, 'mine' solutions for new information (for example, have you ever read a paper thinking "I wonder what the helicity density looks like?"), compare new techniques with older results, collaborate with remote colleagues, and perform validation. Supporting meta-information associated with the research projects is also important to provide additional context for research projects. This may include information such as the software used in the simulation (e.g. grid generators, flow solvers, visualization). In addition to serving the CAS research community, the information archive will also be helpful to students, visualization system developers and researchers, and management. Students (of any age) can use the data to study fluid dynamics, compare results from different flow solvers, learn about meshing techniques, etc., leading to better informed individuals. For these users it is particularly important that visualization be integrated into dataset archives. Visualization researchers can use dataset archives to test algorithms and techniques, leading to better visualization systems, Management can use the data to figure what is really going on behind the viewgraphs. All users will benefit from fast, easy, and convenient access to CFD datasets. The CAS information archive hopes to serve as a useful resource to

  18. Time-resolved photoluminescence studies of annealed 1.3-μm GaInNAsSb quantum wells

    PubMed Central

    2014-01-01

    Time-resolved photoluminescence (PL) was applied to study the dynamics of carrier recombination in GaInNAsSb quantum wells (QWs) emitting near 1.3 μm and annealed at various temperatures. It was observed that the annealing temperature has a strong influence on the PL decay time, and hence, it influences the optical quality of GaInNAsSb QWs. At low temperatures, the PL decay time exhibits energy dependence (i.e., the decay times change for different energies of emitted photons), which can be explained by the presence of localized states. This energy dependence of PL decay times was fitted by a phenomenological formula, and the average value of E0, which describes the energy distribution of localized states, was extracted from this fit and found to be smallest (E0 = 6 meV) for the QW annealed at 700°C. In addition, the value of PL decay time at the peak energy was compared for all samples. The longest PL decay time (600 ps) was observed for the sample annealed at 700°C. It means that based on the PL dynamics, the optimal annealing temperature for this QW is approximately 700°C. PMID:24533740

  19. NAS: The first year

    NASA Technical Reports Server (NTRS)

    Bailey, F. R.; Kutler, Paul

    1988-01-01

    Discussed are the capabilities of NASA's Numerical Aerodynamic Simulation (NAS) Program and its application as an advanced supercomputing system for computational fluid dynamics (CFD) research. First, the paper describes the NAS computational system, called the NAS Processing System Network, and the advanced computational capabilities it offers as a consequence of carrying out the NAS pathfinder objective. Second, it presents examples of pioneering CFD research accomplished during NAS's first operational year. Examples are included which illustrate CFD applications for predicting fluid phenomena, complementing and supplementing experimentation, and aiding in design. Finally, pacing elements and future directions for CFD and NAS are discussed.

  20. 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

  1. 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.

  2. Defect study of molecular beam epitaxy grown undoped GaInNAsSb thin film using junction-capacitance spectroscopy

    SciTech Connect

    Monirul Islam, Muhammad; Miyashita, Naoya; Ahsan, Nazmul; Okada, Yoshitaka

    2013-02-18

    Defects in undoped GaInNAsSb thin film (i-GaInNAsSb) were investigated by junction-capacitance technique using admittance and transient photocapacitance (TPC) spectroscopy. An electron trap D2 was identified at 0.34 eV below the conduction band (E{sub C}) of i-GaInNAsSb using admittance spectroscopy. Optical transition of valance band (E{sub V}) electrons to a localized state OH1 (E{sub V} + 0.75 eV) was manifested in negative TPC signal. Combined activation energy of OH1 and D2 defect corresponds to the band-gap of i-GaInNAsSb, suggesting that OH1/D2 acts as an efficient recombination center. TPC signal at {approx}1.59 eV above E{sub V} was attributed to the nitrogen-induced localized state in GaInNAsSb.

  3. 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.

  4. 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

  5. The NAS Computational Aerosciences Archive

    NASA Technical Reports Server (NTRS)

    Miceli, Kristina D.; Globus, Al; Lasinski, T. A. (Technical Monitor)

    1995-01-01

    performed by NAS staff members and collaborators. Visual results, which may be available in the form of images, animations, and/or visualization scripts, are generated by researchers with respect to a certain research project, depicting dataset features that were determined important by the investigating researcher. For example, script files for visualization systems (e.g. FAST, PLOT3D, AVS) are provided to create visualizations on the user's local workstation to elucidate the key points of the numerical study. Users can then interact with the data starting where the investigator left off. Datasets are intended to give researchers an opportunity to understand previous work, 'mine' solutions for new information (for example, have you ever read a paper thinking "I wonder what the helicity density looks like?"), compare new techniques with older results, collaborate with remote colleagues, and perform validation. Supporting meta-information associated with the research projects is also important to provide additional context for research projects. This may include information such as the software used in the simulation (e.g. grid generators, flow solvers, visualization). In addition to serving the CAS research community, the information archive will also be helpful to students, visualization system developers and researchers, and management. Students (of any age) can use the data to study fluid dynamics, compare results from different flow solvers, learn about meshing techniques, etc., leading to better informed individuals. For these users it is particularly important that visualization be integrated into dataset archives. Visualization researchers can use dataset archives to test algorithms and techniques, leading to better visualization systems, Management can use the data to figure what is really going on behind the viewgraphs. All users will benefit from fast, easy, and convenient access to CFD datasets. The CAS information archive hopes to serve as a useful resource to

  6. The NAS Parallel Benchmarks

    SciTech Connect

    Bailey, David H.

    2009-11-15

    The NAS Parallel Benchmarks (NPB) are a suite of parallel computer performance benchmarks. They were originally developed at the NASA Ames Research Center in 1991 to assess high-end parallel supercomputers. Although they are no longer used as widely as they once were for comparing high-end system performance, they continue to be studied and analyzed a great deal in the high-performance computing community. The acronym 'NAS' originally stood for the Numerical Aeronautical Simulation Program at NASA Ames. The name of this organization was subsequently changed to the Numerical Aerospace Simulation Program, and more recently to the NASA Advanced Supercomputing Center, although the acronym remains 'NAS.' The developers of the original NPB suite were David H. Bailey, Eric Barszcz, John Barton, David Browning, Russell Carter, LeoDagum, Rod Fatoohi, Samuel Fineberg, Paul Frederickson, Thomas Lasinski, Rob Schreiber, Horst Simon, V. Venkatakrishnan and Sisira Weeratunga. The original NAS Parallel Benchmarks consisted of eight individual benchmark problems, each of which focused on some aspect of scientific computing. The principal focus was in computational aerophysics, although most of these benchmarks have much broader relevance, since in a much larger sense they are typical of many real-world scientific computing applications. The NPB suite grew out of the need for a more rational procedure to select new supercomputers for acquisition by NASA. The emergence of commercially available highly parallel computer systems in the late 1980s offered an attractive alternative to parallel vector supercomputers that had been the mainstay of high-end scientific computing. However, the introduction of highly parallel systems was accompanied by a regrettable level of hype, not only on the part of the commercial vendors but even, in some cases, by scientists using the systems. As a result, it was difficult to discern whether the new systems offered any fundamental performance advantage

  7. A Validation Study of Merging and Spacing Techniques in a NAS-Wide Simulation

    NASA Technical Reports Server (NTRS)

    Glaab, Patricia C.

    2011-01-01

    In November 2010, Intelligent Automation, Inc. (IAI) delivered an M&S software tool to that allows system level studies of the complex terminal airspace with the ACES simulation. The software was evaluated against current day arrivals in the Atlanta TRACON using Atlanta's Hartsfield-Jackson International Airport (KATL) arrival schedules. Results of this validation effort are presented describing data sets, traffic flow assumptions and techniques, and arrival rate comparisons between reported landings at Atlanta versus simulated arrivals using the same traffic sets in ACES equipped with M&S. Initial results showed the simulated system capacity to be significantly below arrival capacity seen at KATL. Data was gathered for Atlanta using commercial airport and flight tracking websites (like FlightAware.com), and analyzed to insure compatible techniques were used for result reporting and comparison. TFM operators for Atlanta were consulted for tuning final simulation parameters and for guidance in flow management techniques during high volume operations. Using these modified parameters and incorporating TFM guidance for efficiencies in flowing aircraft, arrival capacity for KATL was matched for the simulation. Following this validation effort, a sensitivity study was conducted to measure the impact of variations in system parameters on the Atlanta airport arrival capacity.

  8. A Comparison of Brunt Criteria, the Non Alcoholic Fatty Liver Disease Activity Score (NAS) & a Proposed NAS-including fibrosis as Valid Diagnostic Scores for NASH

    PubMed Central

    Santiago-Rolón, Amarilys; Purcell, Dagmary; Rosado, Kathia; Toro, Doris H.

    2016-01-01

    Objective Non-alcoholic steatohepatitis (NASH) can result in cirrhosis and end stage liver disease. It is of utmost importance to differentiate NASH from simple steatosis. The aim of this study is to determine the prevalence of NASH in Latino veterans with metabolic syndrome and compare histologic grading using Brunt Criteria, the NAFLD activity score (NAS), and a proposed NAS score including fibrosis. Methods Veterans with metabolic syndrome, hepatic steatosis and elevation of ALT/AST who underwent a liver biopsy from 2004-2010 were included in this study. Biopsies were evaluated by a single blinded Hepatopathologist. Steatosis, lobular inflammation, ballooning and fibrosis were graded per specimen. Each biopsy was evaluated using Brunt criteria, NAS and NAS plus fibrosis. Results Sixty patients were included in this study, 88.3% men with a mean age of 50.4 (± 12.8). 50.0% met criteria for NASH according to the Brunt system. When classifying biopsies using NAS, only 30.0% (18/60) had a score ≥5, while when adding fibrosis, the number of patients with a score ≥5 increased to 33 (55.0%). When evaluating the predictive ability of the two scoring systems, we found that NAS including fibrosis had a higher sensitivity than NAS (86.7% vs. 40.0%) and a lower specificity (76.7% vs. 80.0%). Conclusion In our population with metabolic syndrome and altered liver function tests, about 50-55% had steatohepatitis. There were significant differences between the scoring systems. When using NAS-plus-fibrosis more patients were recognized and the sensitivity increased. Further validation studies are required to evaluate this proposed NAS scoring System. PMID:26602577

  9. [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.

  10. GaInNAs laser gain

    SciTech Connect

    CHOW,WENG W.; JONES,ERIC D.; MODINE,NORMAND A.; KURTZ,STEVEN R.; ALLERMAN,ANDREW A.

    2000-05-23

    The optical gain spectra for GaInNAs/GaAs quantum wells are computed using a microscopic laser theory. From these spectra, the peak gain and carrier radiative decay rate as functions of carrier density are determined. These dependences allow the study of the lasing threshold current density of GaInNAs/GaAs quantum well structures.

  11. MOVPE growth studies of Ga(NAsP)/(BGa)(AsP) multi quantum well heterostructures (MQWH) for the monolithic integration of laser structures on (001) Si-substrates

    NASA Astrophysics Data System (ADS)

    Ludewig, P.; Reinhard, S.; Jandieri, K.; Wegele, T.; Beyer, A.; Tapfer, L.; Volz, K.; Stolz, W.

    2016-03-01

    High-quality, pseudomorphically strained Ga(NAsP)/(BGa)(AsP)-multiple quantum well heterostructures (MQWH) have been deposited on exactly oriented (001) Si-substrate by metal organic vapour phase epitaxy (MOVPE) in a wide temperature range between 525 °C and 700 °C. The individual atomic incorporation efficiencies, growth rates as well as nanoscale material properties have been clarified by applying detailed high-resolution X-ray diffraction (HR-XRD), photoluminescence (PL) spectroscopy and high-angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) studies. An almost constant N-incorporation efficiency is obtained for a wide growth temperature range from 550 °C up to 650 °C. The P-incorporation is steadily increasing with increasing growth temperature reaching values at high temperatures in excess of the applied gas phase ratio. While the lower interface from the binary GaP- to the quaternary Ga(NAsP)-material system is very sharp, the upper interface is significantly rougher with a roughness scale of ±0.43 nm in quantum well thickness variation at a growth temperature of 525 °C. This roughness scale increases steadily with increasing growth temperature. No indication of any phase separation effects is detected in the Ga(NAsP)-material system even at the highest growth temperature of 700 °C. The obtained experimental results are briefly discussed with respect to the anticipated metastable character of the novel dilute-nitride Ga(NAsP)-material system grown lattice-matched to (001) Si-substrate.

  12. Simultaneous Estimation of Hydrochlorothiazide, Hydralazine Hydrochloride, and Reserpine Using PCA, NAS, and NAS-PCA.

    PubMed

    Sharma, Chetan; Badyal, Pragya Nand; Rawal, Ravindra K

    2015-01-01

    In this study, new and feasible UV-visible spectrophotometric and multivariate spectrophotometric methods were described for the simultaneous determination of hydrochlorothiazide (HCTZ), hydralazine hydrochloride (H.HCl), and reserpine (RES) in combined pharmaceutical tablets. Methanol was used as a solvent for analysis and the whole UV region was scanned from 200-400 nm. The resolution was obtained by using multivariate methods such as the net analyte signal method (NAS), principal component analysis (PCA), and net analyte signal-principal component analysis (NAS-PCA) applied to the UV spectra of the mixture. The results obtained from all of the three methods were compared. NAS-PCA showed a lot of resolved data as compared to NAS and PCA. Thus, the NAS-PCA technique is a combination of NAS and PCA methods which is advantageous to obtain the information from overlapping results.

  13. 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…

  14. Beyond lithium-ion batteries: A computational study on Na-S and Na-O batteries

    NASA Astrophysics Data System (ADS)

    Masedi, M. C.; Ngoepe, P. E.; Sithole, H. M.

    2017-02-01

    The first principle pseudopotential calculations based on the Perdew-Burke-Ernzerhof (PBE) form of generalized gradient approximation (GGA) within density functional theory (DFT) has been utilized to investigate the stabilities of insoluble discharge products of oxygen and sulphur in the Na-O and Na-S batteries. Their structural, mechanical and electronic properties were determined. The lattice parameters were well reproduced and agree with the available experimental data. The heats of formation predict that all structures are generally stable and Na2S has the lowest value. The elastic constants suggest that all the structures are mechanically stable which in good agreement with the calculated phonon dispersions.

  15. 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.

  16. New NAS journal

    NASA Astrophysics Data System (ADS)

    In April 1984 the National Academy of Sciences (NAS) will begin publishing a new quarterly focusing on science policy. Written primarily for legislators, diplomats, corporate managers, security analysts, and other public policy analysts, the new journal will deal with such diverse topics as arms control, economic competition, social change, and health care.Original articles are expected to create a 120-page periodical that will discuss policy issues on a sophisticated but nonspecialist level, in a manner similar to that which Foreign Affairs uses to discuss U.S. foreign policy topics, according to NAS.

  17. 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

  18. 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.

  19. 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

  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. 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.

  3. 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.

  4. NAS Panel faults export controls

    NASA Astrophysics Data System (ADS)

    Katzoff, Judith A.

    A study prepared by a top-level panel says that current export controls on militarily sensitive U.S. technology may be “overcorrecting” previous weaknesses in that system, resulting in “a complex and confusing control system” that makes it more difficult for U.S. businesses to compete in international markets. Moreover, this control system has “an increasingly corrosive effect” on U.S. relations with allies. The panel recommended that the United States concentrate more effort on bringing about uniformity in the export control policies of countries belonging to the Coordinating Committee on Multilateral Export Controls (CoCom), i.e., most of the member nations in NATO (the North Atlantic Treaty Organization) and Japan.The 21-member panel was appointed by the Committee on Science, Engineering, and Public Policy (COSEPUP), a joint unit of the National Academy of Sciences (NAS), the National Academy of Engineering (NAE), and the Institute of Medicine (IOM). The panel, composed of administrators, researchers, and former government officials, was chaired by AGU member Lew Allen, Jr., director of the Jet Propulsion Laboratory (Pasadena, Calif.) and former chief of staff of the U.S. Air Force. Their report was supported by NAS funds, by a number of private organizations (including AGU), by the U.S. Departments of Commerce, Defense, Energy, and State, by the National Science Foundation, and by the National Aeronautics and Space Administration.

  5. 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.

  6. 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.

  7. 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

  8. 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

  9. Supercomputing 2002: NAS Demo Abstracts

    NASA Technical Reports Server (NTRS)

    Parks, John (Technical Monitor)

    2002-01-01

    The hyperwall is a new concept in visual supercomputing, conceived and developed by the NAS Exploratory Computing Group. The hyperwall will allow simultaneous and coordinated visualization and interaction of an array of processes, such as a the computations of a parameter study or the parallel evolutions of a genetic algorithm population. Making over 65 million pixels available to the user, the hyperwall will enable and elicit qualitatively new ways of leveraging computers to accomplish science. It is currently still unclear whether we will be able to transport the hyperwall to SC02. The crucial display frame still has not been completed by the metal fabrication shop, although they promised an August delivery. Also, we are still working the fragile node issue, which may require transplantation of the compute nodes from the present 2U cases into 3U cases. This modification will increase the present 3-rack configuration to 5 racks.

  10. UAS in the NAS Air Traffic Controller Acceptability Study-1: The Effects of Horizontal Miss Distances on Simulated UAS and Manned Aircraft Encounters

    NASA Technical Reports Server (NTRS)

    Ghatas, Rania W.; Comstock, James R., Jr.; Consiglio, Maria C.; Chamberlain, James P.; Hoffler, Keith D.

    2015-01-01

    This study examined air traffic controller acceptability ratings based on the effects of differing horizontal miss distances (HMDs) for encounters between UAS and manned aircraft. In a simulation of the Dallas/Fort Worth (DFW) East-side airspace, the CAS-1 experiment at NASA Langley Research Center enlisted fourteen recently retired DFW air traffic controllers to rate well-clear volumes based on differing HMDs that ranged from 0.5 NM to 3.0 NM. The controllers were tasked with rating these HMDs from "too small" to "too excessive" on a defined, 1-5, scale and whether these distances caused any disruptions to the controller and/or to the surrounding traffic flow. Results of the study indicated a clear favoring towards a particular HMD range. Controller workload was also measured. Data from this experiment and subsequent experiments will play a crucial role in the FAA's establishment of rules, regulations, and procedures to safely and efficiently integrate UAS into the NAS.

  11. 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.

  12. Transmission electron microscopy study of GaInNAs(Sb) thin films grown by atomic hydrogen-assisted molecular beam epitaxy

    NASA Astrophysics Data System (ADS)

    Oshima, R.; Huang, J. Y.; Miyashita, N.; Matsubara, K.; Okada, Y.; Ponce, F. A.

    2011-11-01

    The quaternary GaInNAs is a promising material system for use in next generation multijunction photovoltaic devices. We have investigated the effect of introducing antimony on the growth by using transmission electron microscopy and energy dispersive x-ray (EDX) spectroscopy. Two-dimensional growth was observed in GaInNAs films with striation features associated with compositional fluctuation and nanometer scale elemental segregation on the growth front. On the contrary, GaInNAsSb films exhibit uniform contrast throughout. EDX profile indicates uniform compositional distribution, as antimony atoms suppress the surface mobilites of adatoms resulting in a lower probability to generate the favored bonds, such as Ga-N and In-As.

  13. 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 ...

  14. 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 ...

  15. 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…

  16. [The NAS system: Nursing Activities Score in mobile technology].

    PubMed

    Catalan, Vanessa Menezes; Silveira, Denise Tolfo; Neutzling, Agnes Ludwig; Martinato, Luísa Helena Machado; Borges, Gilberto Cabral de Mello

    2011-12-01

    The objective of this study was to present the computerized structure that enables the use of the Nursing Activities Score (NAS) in mobile technology. It is a project for the development of technology production based on software engineering, founded on the theory of systems development life cycle. The NAS system was built in two modules: the search module, which is accessed using a personal computer (PC), and Data Collection module, which is accessed through a mobile device (Smartphone). The NAS system was constructed to allow other forms, in addition to the NAS tool, to be included in the future. Thus, it is understood that the development of the NAS will bring nurses closer to mobile technology and facilitate their accessibility to the data of the instrument relating to patients, thus assisting in decision-making and in staffing to provide nursing care.

  17. 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.

  18. 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)

  19. 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.

  20. [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.

  1. 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.

  2. 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.

  3. 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

  4. 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…

  5. 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

  6. SMART NAS Test Bed Overview

    NASA Technical Reports Server (NTRS)

    Palopo, Kee

    2016-01-01

    These slides presents an overview of SMART NAS Test Bed. The test bed is envisioned to be connected to operational systems and to allow a new concept and technology to be evaluated in its realistic environment. Its role as an accelerator of concepts and technologies development, its use-case-driven development approach, and its state are presented.

  7. The NAS kernel benchmark program

    NASA Technical Reports Server (NTRS)

    Bailey, D. H.; Barton, J. T.

    1985-01-01

    A collection of benchmark test kernels that measure supercomputer performance has been developed for the use of the NAS (Numerical Aerodynamic Simulation) program at the NASA Ames Research Center. This benchmark program is described in detail and the specific ground rules are given for running the program as a performance test.

  8. NAS Applications and Advanced Algorithms

    NASA Technical Reports Server (NTRS)

    Bailey, David H.; Biswas, Rupak; VanDerWijngaart, Rob; Kutler, Paul (Technical Monitor)

    1997-01-01

    This paper examines the applications most commonly run on the supercomputers at the Numerical Aerospace Simulation (NAS) facility. It analyzes the extent to which such applications are fundamentally oriented to vector computers, and whether or not they can be efficiently implemented on hierarchical memory machines, such as systems with cache memories and highly parallel, distributed memory systems.

  9. Effects of the 5-HT1B receptor antagonist NAS-181 on extracellular levels of acetylcholine, glutamate and GABA in the frontal cortex and ventral hippocampus of awake rats: a microdialysis study.

    PubMed

    Hu, Xiao Jing; Wang, Fu-Hua; Stenfors, Carina; Ogren, Sven Ove; Kehr, Jan

    2007-09-01

    The purpose of this study was to investigate the effects of the 5-HT(1B) receptor antagonist NAS-181 ((R)-(+)-2-(3-morpholinomethyl-2H-chromen-8-yl) oxymethyl-morpholine methanesulfonate) on cholinergic, glutamatergic and GABA-ergic neurotransmission in the rat brain in vivo. Extracellular levels of acetylcholine, glutamate and GABA were monitored by microdialysis in the frontal cortex (FC) and ventral hippocampus (VHipp) in separate groups of freely moving rats. NAS-181 (1, 5 or 10 mg/kg, s.c.) caused a dose-dependent increase in ACh levels, reaching the maximal values of 500% (FC) and 230% (VHipp) of controls at 80 min post-injection. On the contrary, NAS-181 injected at doses of 10 or 20 mg/kg s.c. had no effect on basal extracellular levels of Glu and GABA in these areas. The present data suggest that ACh neurotransmission in the FC and VHipp, the brain structures strongly implicated in cognitive function, is under tonic inhibitory control of 5-HT(1B) heteroreceptors localized at the cholinergic terminals in these areas.

  10. 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)

  11. NASA's UAS NAS Access Project

    NASA Technical Reports Server (NTRS)

    Johnson, Charles W.

    2011-01-01

    The vision of the Unmanned Aircraft System (UAS) Integration in the National Airspace System (NAS) Project is "A global transportation system which allows routine access for all classes of UAS." The goal of the UAS Integration in the NAS Project is to "contribute capabilities that reduce technical barriers related to the safety and operational challenges associated with enabling routine UAS access to the NAS." This goal will be accomplished through a two-phased approach based on development of system-level integration of key concepts, technologies and/or procedures, and demonstrations of integrated capabilities in an operationally relevant environment. Phase 1 will take place the first two years of the Project and Phase 2 will take place the following three years. The Phase 1 and 2 technical objectives are: Phase 1: Developing a gap analysis between current state of the art and the Next Generation Air Transportation System (NextGen) UAS Concept of Operations . Validating the key technical areas identified by this Project . Conducting initial modeling, simulation, and flight testing activities . Completing Sub-project Phase 1 deliverables (spectrum requirements, comparative analysis of certification methodologies, etc.) and continue Phase 2 preparation (infrastructure, tools, etc.) Phase 2: Providing regulators with a methodology for developing airworthiness requirements for UAS, and data to support development of certifications standards and regulatory guidance . Providing systems-level, integrated testing of concepts and/or capabilities that address barriers to routine access to the NAS. Through simulation and flight testing, address issues including separation assurance, communications requirements, and human systems integration in operationally relevant environments. The UAS in the NAS Project will demonstrate solutions in specific technology areas, which will address operational/safety issues related to UAS access to the NAS. Since the resource allocation for

  12. 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.

  13. 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

  14. New NAS Parallel Benchmarks Results

    NASA Technical Reports Server (NTRS)

    Yarrow, Maurice; Saphir, William; VanderWijngaart, Rob; Woo, Alex; Kutler, Paul (Technical Monitor)

    1997-01-01

    NPB2 (NAS (NASA Advanced Supercomputing) Parallel Benchmarks 2) is an implementation, based on Fortran and the MPI (message passing interface) message passing standard, of the original NAS Parallel Benchmark specifications. NPB2 programs are run with little or no tuning, in contrast to NPB vendor implementations, which are highly optimized for specific architectures. NPB2 results complement, rather than replace, NPB results. Because they have not been optimized by vendors, NPB2 implementations approximate the performance a typical user can expect for a portable parallel program on distributed memory parallel computers. Together these results provide an insightful comparison of the real-world performance of high-performance computers. New NPB2 features: New implementation (CG), new workstation class problem sizes, new serial sample versions, more performance statistics.

  15. 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).

  16. 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.

  17. The SMART-NAS Testbed

    NASA Technical Reports Server (NTRS)

    Aquilina, Rudolph A.

    2015-01-01

    The SMART-NAS Testbed for Safe Trajectory Based Operations Project will deliver an evaluation capability, critical to the ATM community, allowing full NextGen and beyond-NextGen concepts to be assessed and developed. To meet this objective a strong focus will be placed on concept integration and validation to enable a gate-to-gate trajectory-based system capability that satisfies a full vision for NextGen. The SMART-NAS for Safe TBO Project consists of six sub-projects. Three of the sub-projects are focused on exploring and developing technologies, concepts and models for evolving and transforming air traffic management operations in the ATM+2 time horizon, while the remaining three sub-projects are focused on developing the tools and capabilities needed for testing these advanced concepts. Function Allocation, Networked Air Traffic Management and Trajectory Based Operations are developing concepts and models. SMART-NAS Test-bed, System Assurance Technologies and Real-time Safety Modeling are developing the tools and capabilities to test these concepts. Simulation and modeling capabilities will include the ability to assess multiple operational scenarios of the national airspace system, accept data feeds, allowing shadowing of actual operations in either real-time, fast-time and/or hybrid modes of operations in distributed environments, and enable integrated examinations of concepts, algorithms, technologies, and NAS architectures. An important focus within this project is to enable the development of a real-time, system-wide safety assurance system. The basis of such a system is a continuum of information acquisition, analysis, and assessment that enables awareness and corrective action to detect and mitigate potential threats to continuous system-wide safety at all levels. This process, which currently can only be done post operations, will be driven towards "real-time" assessments in the 2035 time frame.

  18. Update on the NAS-NRC Twin Registry.

    PubMed

    Page, William F

    2006-12-01

    The National Academy of Sciences-National Research Council (NAS-NRC) Twin Registry is one of the oldest, national population-based twin registries in the United States. It consists of 15,924 white male twin pairs born in the years 1917 to 1927 (inclusive), both of whom served in the armed forces, mostly during World War II. This article updates activity in this registry since the earlier 2002 article in Twin Research. The results of clinically based studies on dementia, Parkinson's disease, age-related macular degeneration, and primary osteoarthritis were published, as well as articles based on previously collected questionnaire data on chronic fatigue syndrome, functional limitations, and healthy aging. In addition, risk factor studies are being planned to merge clinical data with earlier collected risk factor data from questionnaires. Examination data from the subset of National Heart, Lung, and Blood Institute (NHLBI) twins resulted in a number of articles, including the relationship of endogenous sex hormones to coronary heart disease and morphological changes in aging brain structures. The NEO Five-Factor Personality Inventory (a paper-and-pencil self-administered questionnaire) has been fielded for the first time. A push to consolidate the various data holdings of the registry is being made.

  19. "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.

  20. 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…

  1. 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…

  2. 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…

  3. 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)

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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

  11. 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.

  12. 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

  13. 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

  14. 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)…

  15. 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

  16. 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

  17. 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.

  18. [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.

  19. UAS-NAS Stakeholder Feedback Report

    NASA Technical Reports Server (NTRS)

    Randall, Debra; Murphy, Jim; Grindle, Laurie

    2016-01-01

    The need to fly UAS in the NAS to perform missions of vital importance to national security and defense, emergency management, science, and to enable commercial applications has been continually increasing over the past few years. To address this need, the NASA Aeronautics Research Mission Directorate (ARMD) Integrated Aviation Systems Program (IASP) formulated and funded the Unmanned Aircraft Systems (UAS) Integration in the National Airspace System (NAS) Project (hereafter referred to as UAS-NAS Project) from 2011 to 2016. The UAS-NAS Project identified the following need statement: The UAS community needs routine access to the global airspace for all classes of UAS. The Project identified the following goal: To provide research findings to reduce technical barriers associated with integrating UAS into the NAS utilizing integrated system level tests in a relevant environment. This report provides a summary of the collaborations between the UAS-NAS Project and its primary stakeholders and how the Project applied and incorporated the feedback.

  20. 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…

  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. 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

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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

  8. 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

  9. 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.

  10. 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…

  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. National Air Space (NAS) Data Exchange Environment Through 2060

    NASA Technical Reports Server (NTRS)

    Roy, Aloke

    2015-01-01

    NASA's NextGen Concepts and Technology Development (CTD) Project focuses on capabilities to improve safety, capacity and efficiency of the National Air Space (NAS). In order to achieve those objectives, NASA sought industry-Government partnerships to research and identify solutions for traffic flow management, dynamic airspace configuration, separation assurance, super density operations, airport surface operations and similar forward-looking air-traffic modernization (ATM) concepts. Data exchanges over NAS being the key enabler for most of these ATM concepts, the Sub-Topic area 3 of the CTD project sought to identify technology candidates that can satisfy air-to-air and air/ground communications needs of the NAS in the year 2060 timeframe. Honeywell, under a two-year contract with NASA, is working on this communications technology research initiative. This report summarizes Honeywell's research conducted during the second year of the study task.

  13. 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.

  14. 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

  15. 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.

  16. 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.

  17. 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…

  18. 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

  19. 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

  20. 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.

  1. 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)

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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

  8. 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.

  9. 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

  10. 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.

  11. [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.

  12. 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].

  13. 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.

  14. 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.

  15. NASA Advanced Supercomputing (NAS) User Services Group

    NASA Technical Reports Server (NTRS)

    Pandori, John; Hamilton, Chris; Niggley, C. E.; Parks, John W. (Technical Monitor)

    2002-01-01

    This viewgraph presentation provides an overview of NAS (NASA Advanced Supercomputing), its goals, and its mainframe computer assets. Also covered are its functions, including systems monitoring and technical support.

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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.…

  1. UAS NAS IHITL Test Readiness Review (TRR)

    NASA Technical Reports Server (NTRS)

    Murphy, Jim; Brignola, Michael P.; Rorie, Conrad; Santiago, Confesor; Guminsky, Mike; Cross, Ken

    2014-01-01

    Requesting release of IHITL test readiness review (TRR) charts to ensure UAS-NAS project primary stakeholders, the Federal Aviation Administration through the RTCA special committee -228 and the Office of the Secretary of Defense Sense and Avoid Science and Research Panel, are well informed on the IHITL test plan and expected outcomes as they relate to their needs to safely fly UAS in the NAS.

  2. 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.

  3. 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

  4. 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…

  5. 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

  6. Natural Attenuation Software (NAS): A computer program for estimating remediation times of contaminated groundwater

    USGS Publications Warehouse

    Mendez, E.; Widdowson, M.; Brauner, S.; Chapelle, F.; Casey, C.; ,

    2004-01-01

    This paper describes the development and application of a modeling system called Natural Attenuation Software (NAS). NAS was designed as a screening tool to estimate times of remediation (TORs), associated with monitored natural attenuation (MNA), to lower groundwater contaminant concentrations to regulatory limits. Natural attenuation processes that NAS models include advection, dispersion, sorption, biodegradation, and non-aqueous phase liquid (NAPL) dissolution. This paper discusses the three main interactive components of NAS: 1) estimation of the target source concentration required for a plume extent to contract to regulatory limits, 2) estimation of the time required for NAFL contaminants in the source area to attenuate to a predetermined target source concentration, and 3) estimation of the time required for a plume extent to contract to regulatory limits after source reduction. The model's capability is illustrated by results from a case study at a MNA site, where NAS time of remediation estimates compared well with observed monitoring data over multiple years.

  7. 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…

  8. 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)

  9. 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).

  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. Antimycobacterial Activity and Mechanism of Action of NAS-91.

    PubMed

    Gratraud, Paul; Surolia, Namita; Besra, Gurdyal S; Surolia, Avadhesha; Kremer, Laurent

    2008-03-01

    The antimalarial agents NAS-91 and NAS-21 were found to express potent antimycobacterial activity, NAS-91 being more active than NAS-21. They partially inhibited mycolic acid biosynthesis and profoundly altered oleic acid production. The development of a cell-free assay for Delta 9-desaturase activity allowed direct demonstration of the inhibition of oleic acid biosynthesis by these compounds.

  14. Status and projections of the NAS program

    NASA Technical Reports Server (NTRS)

    Bailey, Frank R.

    1986-01-01

    NASA's Numerical Aerodynamic Simulation (NAS) Program has completed development of the initial operating configuration of the NAS Processing System Network (NPSN). This is the first milestone in the continuing and pathfinding effort to provide state-of-the-art supercomputing for aeronautics research and development. The NPSN, available to a nation-wide community of remote users, provides a uniform UNIX environment over a network of host computers ranging from the Cray-2 supercomputer to advanced scientific workstations. This system, coupled with a vendor-independent base of common user interface and network software, presents a new paradigm for supercomputing environments. Background leading to the NAS program, its programmatic goals and strategies, technical goals and objectives, and the development activities leading to the current NPSN configuration are presented. Program status, near-term plans, and plans for the next major milestone, the extended operating configuration, are also discussed.

  15. 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

  16. 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.

  17. 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…

  18. Synthesis and biological evaluation of NAS-21 and NAS-91 analogues as potential inhibitors of the mycobacterial FAS-II dehydratase enzyme Rv0636.

    PubMed

    Bhowruth, Veemal; Brown, Alistair K; Besra, Gurdyal S

    2008-07-01

    The identification of potential new anti-tubercular chemotherapeutics is paramount due to the recent emergence of extensively drug-resistant strains of Mycobacterium tuberculosis (XDR-TB). Libraries of NAS-21 and NAS-91 analogues were synthesized and evaluated for their whole-cell activity against Mycobacterium bovis BCG. NAS-21 analogues 1 and 2 demonstrated enhanced whole-cell activity in comparison to the parental compound, and an M. bovis BCG strain overexpressing the dehydratase enzyme Rv0636 was resistant to these analogues. NAS-91 analogues with ortho-modifications gave enhanced whole-cell activity. However, extension with biphenyl modifications compromised the whole-cell activities of both NAS-21 and NAS-91 analogues. Interestingly, both libraries demonstrated in vitro activity against fatty acid synthase II (FAS-II) but not FAS-I in cell-free extracts. In in vitro assays of FAS-II inhibition, NAS-21 analogues 4 and 5 had IC(50) values of 28 and 19 mug ml(-1), respectively, for the control M. bovis strain, and the M. bovis BCG strain overexpressing Rv0636 showed a marked increase in resistance. In contrast, NAS-91 analogues demonstrated moderate in vitro activity, although increased resistance was again observed in FAS-II activity assays with the Rv0636-overexpressing strain. Fatty acid methyl ester (FAME) and mycolic acid methyl ester (MAME) analysis of M. bovis BCG and the Rv0636-overexpressing strain revealed that the effect of the drug was relieved in the overexpressing strain, further implicating and potentially identifying Rv0636 as the target for these known FabZ dehydratase inhibitors. This study has identified candidates for further development as drug therapeutics against the mycobacterial FAS-II dehydratase enzyme.

  19. 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.

  20. 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

  1. 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

  2. UAS Integration into the NAS Project

    NASA Technical Reports Server (NTRS)

    Bauer, Jeff

    2010-01-01

    The goal of the UAS Integration in the NAS Project is to contribute capabilities that reduce technical barriers related to the safety and operational challenges associated with enabling routine UAS access to the NAS This goal will be accomplished through a two-phased approach of system-level integration of key concepts, technologies and/or procedures, and demonstrations of integrated capabilities in an operationally relevant environment. Technical objectives include: PHASE 1: a) Validating the key technical areas identified by this project. System-level analyses, a State of the Art Analysis (SOAA), and a ConOps will identify the challenges and barriers preventing routine UAS access to the NAS. b) Developing a national roadmap and gap analysis identifying specific deliverables in the area of operations, procedures, and technologies that will impact future policy decisions. PHASE 2: a) Provide regulators with a methodology for developing airworthiness requirements for UAS and data to support development of certifications standards and regulatory guidance. b) Provide systems-level integrated testing of concepts and/or capabilities that address barriers to routine access to the NAS. Through simulation and flight testing, address issues including separation assurance, communications requirements, and Pilot Aircraft Interfaces (PAIs) in operationally relevant environments

  3. 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)

  4. 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.

  5. 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.

  6. 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.

  7. [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.

  8. 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…

  9. Verification of Self-Report of Zygosity Determined via DNA Testing in a Subset of the NAS-NRC Twin Registry 40 Years Later

    PubMed Central

    Reed, T.; Plassman, B.L.; Tanner, C.M.; Dick, D. M.; Rinehart, S.A.; Nichols, W.C.

    2005-01-01

    The National Academy of Sciences – National Research Council (NAS-NRC) twin panel, created nearly 50 years ago, had twin zygosity determined primarily via a similarity questionnaire that has been estimated to correctly classify at least 95% of twins. In the course of a study on the genetics of healthy aging in the NAS-NRC twins DNA was collected for genome-wide scanning and zygosity confirmation was examined in 343 participating pairs. The sample was supplemented from two other studies using NAS-NRC twins where one or both co-twins were suspected to have Alzheimer disease or another dementia, or Parkinson’s disease. Overall there were 578 twin-pairs with DNA analyzed. 96.8% (519/536) had confirmation of zygosity assignment via questionnaire. Among 42 pairs whose questionnaire responses were inconclusive for assigning zygosity, 50% were found to be monozygous and 50% were dizygous. There was some evidence for greater misclassification of presumed DZ pairs in the healthy aging study where participation favored pairs who were similar in having a favorable health history and willingness to volunteer without any element of perceived risk for a specific disease influencing participation. PMID:16176721

  10. 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…

  11. Heavy Metals Need Assistance: The Contribution of Nicotianamine to Metal Circulation Throughout the Plant and the Arabidopsis NAS Gene Family.

    PubMed

    Schuler, Mara; Bauer, Petra

    2011-01-01

    Understanding the regulated inter- and intra-cellular metal circulation is one of the challenges in the field of metal homeostasis. Inside organisms metal ions are bound to organic ligands to prevent their uncontrolled reactivity and to increase their solubility. Nicotianamine (NA) is one of the important ligands. This non-proteinogenic amino acid is synthesized by nicotianamine synthase (NAS). NA is involved in mobilization, uptake, transport, storage, and detoxification of metals. Much of the progress in understanding NA function has been achieved by studying mutants with altered nicotianamine levels. Mild and strong Arabidopsis mutants impaired in nicotianamine synthesis have been identified and characterized, namely nas4x-1 and nas4x-2. Arabidopsis thaliana has four NAS genes. In this review, we summarize the structure and evolution of the NAS genes in the Arabidopsis genome. We summarize previous results and present novel evidence that the four NAS genes have partially overlapping functions when plants are exposed to Fe deficiency and nickel supply. We compare the phenotypes of nas4x-1 and nas4x-2 and summarize the functions of NAS genes and NA as deduced from the studies of mutant phenotypes.

  12. Cumulative lead exposure is associated with reduced olfactory recognition performance in elderly men: the Normative Aging Study

    PubMed Central

    Grashow, Rachel; Sparrow, David; Hu, Howard; Weisskopf, Marc G.

    2015-01-01

    Introduction Olfactory dysfunction has been identified as an early warning sign for Alzheimer’s disease, Parkinson’s disease, dementia and more. A few occupational and environmental exposures have also been associated with reduced olfactory function, although the effects of long term environmental exposure to lead on olfactory dysfunction have not been explored. Here we performed olfactory recognition testing in elderly men in a community-dwelling cohort and examined the association with cumulative lead exposure, as assessed by lead in tibial and patellar bone. Methods Olfactory recognition was measured in 165 men from the Normative Aging Study (NAS) who had previously taken part in bone lead measurements using K-X-Ray fluorescence (KXRF). Olfactory recognition was measured using the University of Pennsylvania Smell Identification Test (UPSIT). Associations between olfactory recognition, global cognition and cumulative lead exposure were estimated using linear regression, with additional adjustment for age, smoking, and functional polymorphism status for hemochromatosis (HFE), transferrin (TfC2), glutathione-s-transferase Pi1 (GSTP1) and apolipoprotein E (APOE) genotypes. Sensitivity analyses explored olfactory recognition in men with high global cognitive function as measured using the Mini-Mental Status Exam (MMSE). Results The average age of the NAS participants at the time of olfactory recognition testing was 80.3 (standard deviation or SD = 5.7) years. Mean tibia lead was 16.3 (SD = 12.0) μg/g bone, mean patella lead was 22.4 (SD = 14.4) μg/g bone, and mean UPSIT score was 26.9 out of 40 (SD = 7.0). Consistent with previous findings, age at olfaction testing was negatively associated with UPSIT score. Tibia (but not patella) bone lead was negatively associated with olfaction recognition (per 15 μg/g tibia lead: β = −1.57; 95% CI: −2.93, −0.22; p = 0.02) in models adjusted for smoking and age. Additional adjustment for education did not

  13. 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

  14. 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

  15. 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

  16. 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

  17. “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

  18. 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.

  19. NAS Grid Benchmarks. 1.0

    NASA Technical Reports Server (NTRS)

    VanderWijngaart, Rob; Frumkin, Michael; Biegel, Bryan A. (Technical Monitor)

    2002-01-01

    We provide a paper-and-pencil specification of a benchmark suite for computational grids. It is based on the NAS (NASA Advanced Supercomputing) Parallel Benchmarks (NPB) and is called the NAS Grid Benchmarks (NGB). NGB problems are presented as data flow graphs encapsulating an instance of a slightly modified NPB task in each graph node, which communicates with other nodes by sending/receiving initialization data. Like NPB, NGB specifies several different classes (problem sizes). In this report we describe classes S, W, and A, and provide verification values for each. The implementor has the freedom to choose any language, grid environment, security model, fault tolerance/error correction mechanism, etc., as long as the resulting implementation passes the verification test and reports the turnaround time of the benchmark.

  20. NAS Technical Summaries, March 1993 - February 1994

    NASA Technical Reports Server (NTRS)

    1995-01-01

    NASA created the Numerical Aerodynamic Simulation (NAS) Program in 1987 to focus resources on solving critical problems in aeroscience and related disciplines by utilizing the power of the most advanced supercomputers available. The NAS Program provides scientists with the necessary computing power to solve today's most demanding computational fluid dynamics problems and serves as a pathfinder in integrating leading-edge supercomputing technologies, thus benefitting other supercomputer centers in government and industry. The 1993-94 operational year concluded with 448 high-speed processor projects and 95 parallel projects representing NASA, the Department of Defense, other government agencies, private industry, and universities. This document provides a glimpse at some of the significant scientific results for the year.

  1. 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

  2. Implementation of NAS Parallel Benchmarks in Java

    NASA Technical Reports Server (NTRS)

    Frumkin, Michael; Schultz, Matthew; Jin, Hao-Qiang; Yan, Jerry

    2000-01-01

    A number of features make Java an attractive but a debatable choice for High Performance Computing (HPC). In order to gauge the applicability of Java to the Computational Fluid Dynamics (CFD) we have implemented NAS Parallel Benchmarks in Java. The performance and scalability of the benchmarks point out the areas where improvement in Java compiler technology and in Java thread implementation would move Java closer to Fortran in the competition for CFD applications.

  3. 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.

  4. 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…

  5. 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.

  6. 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.

  7. Six Years of Parallel Computing at NAS (1987 - 1993): What Have we Learned?

    NASA Technical Reports Server (NTRS)

    Simon, Horst D.; Cooper, D. M. (Technical Monitor)

    1994-01-01

    In the fall of 1987 the age of parallelism at NAS began with the installation of a 32K processor CM-2 from Thinking Machines. In 1987 this was described as an "experiment" in parallel processing. In the six years since, NAS acquired a series of parallel machines, and conducted an active research and development effort focused on the use of highly parallel machines for applications in the computational aerosciences. In this time period parallel processing for scientific applications evolved from a fringe research topic into the one of main activities at NAS. In this presentation I will review the history of parallel computing at NAS in the context of the major progress, which has been made in the field in general. I will attempt to summarize the lessons we have learned so far, and the contributions NAS has made to the state of the art. Based on these insights I will comment on the current state of parallel computing (including the HPCC effort) and try to predict some trends for the next six years.

  8. Carrier spin relaxation in GaInNAsSb/GaNAsSb/GaAs quantum well

    SciTech Connect

    Asami, T.; Nosho, H.; Tackeuchi, A.; Li, L. H.; Harmand, J. C.; Lu, S. L.

    2011-12-23

    We have investigated the carrier spin relaxation in GaInNAsSb/GaNAsSb/GaAs quantum well (QW) by time-resolved photoluminescence (PL) measurement. The sample consists of an 8-nm-thick GaIn{sub 0.36}N{sub 0.006}AsSb{sub 0.015} well, 5-nm-thick GaN{sub 0.01}AsSb{sub 0.11} intermediate barriers and 100-nm-thick GaAs barriers grown by molecular beam epitaxy on a GaAs(100) substrate. The spin relaxation time and recombination lifetime at 10 K are measured to be 228 ps and 151 ps, respectively. As a reference, we have also obtained a spin relaxation time of 125 ps and a recombination lifetime of 63 ps for GaInNAs/GaNAs/GaAs QW. This result shows that crystal quality is slightly improved by adding Sb, although these short carrier lifetimes mainly originate from a nonradiative recombination. These spin relaxation times are longer than the 36 ps spin relaxation time of InGaAs/InP QWs and shorter than the 2 ns spin relaxation time of GaInNAs/GaAs QW.

  9. 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.

  10. Dilute-As AlNAs Alloy for Deep-Ultraviolet Emitter

    PubMed Central

    Tan, Chee-Keong; Borovac, Damir; Sun, Wei; Tansu, Nelson

    2016-01-01

    The band structures of dilute-As AlNAs alloys with As composition ranging from 0% up to 12.5% are studied by using First-Principle Density Functional Theory (DFT) calculation. The energy band gap shows remarkable reduction from 6.19 eV to 3.87 eV with small amount of As content in the AlNAs alloy, which covers the deep ultraviolet (UV) spectral regime. A giant bowing parameter of 30.5 eV ± 0.5 eV for AlNAs alloy is obtained. In addition, our analysis shows that the crossover between crystal field split-off (CH) band and heavy hole (HH) bands occurs in the dilute-As AlNAs alloy with As-content of ~1.5%. This result implies the possibility of dominant transverse electric (TE)-polarized emission by using AlNAs alloy with dilute amount of As-content. Our findings indicate the potential of dilute-As AlNAs alloy as the new active region material for TE-polarized III-Nitride-based deep UV light emitters. PMID:26905060

  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. 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"…

  16. 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

  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. NAS Parallel Benchmarks. 2.4

    NASA Technical Reports Server (NTRS)

    VanderWijngaart, Rob; Biegel, Bryan A. (Technical Monitor)

    2002-01-01

    We describe a new problem size, called Class D, for the NAS Parallel Benchmarks (NPB), whose MPI source code implementation is being released as NPB 2.4. A brief rationale is given for how the new class is derived. We also describe the modifications made to the MPI (Message Passing Interface) implementation to allow the new class to be run on systems with 32-bit integers, and with moderate amounts of memory. Finally, we give the verification values for the new problem size.

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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).

  6. 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

  7. 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…

  8. 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.

  9. 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

  10. Cohort Profile: The National Academy of Sciences-National Research Council Twin Registry (NAS-NRC Twin Registry).

    PubMed

    Gatz, Margaret; Harris, Jennifer R; Kaprio, Jaakko; McGue, Matt; Smith, Nicholas L; Snieder, Harold; Spiro, Avron; Butler, David A

    2015-06-01

    The National Academy of Sciences-National Research Council Twin Registry (NAS-NRC Twin Registry) is a comprehensive registry of White male twin pairs born in the USA between 1917 and 1927, both of the twins having served in the military. The purpose was medical research and ultimately improved clinical care. The cohort was assembled in the early 1960s with identification of approximately 16,000 twin pairs, review of service records, a brief mailed questionnaire assessing zygosity, and a health survey largely comparable to questionnaires used at that time with Scandinavian twin registries. Subsequent large-scale data collection occurred in 1974, 1985 and 1998, repeating the health survey and including information on education, employment history and earnings. Self-reported data have been supplemented with mortality, disability and medical data through record linkage. Potential collaborators should access the study website [http://www.iom.edu/Activities/Veterans/TwinsStudy.aspx] or e-mail the Medical Follow-up Agency at [Twins@nas.edu]. Questionnaire data are being prepared for future archiving with the National Archive of Computerized Data on Aging (NACDA) at the Inter-University Consortium for Political and Social Research (ICPSR), University of Michigan, MI.

  11. 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.

  12. 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)

  13. 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.

  14. 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.

  15. 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 from foo...

  16. Executed and Imagined Bimanual Movements: A Study across Different Ages

    ERIC Educational Resources Information Center

    Piedimonte, Alessandro; Garbarini, Francesca; Rabuffetti, Marco; Pia, Lorenzo; Berti, Anna

    2014-01-01

    Movements with both hands are essential to our everyday life, and it has been shown that performing asymmetric bimanual movements produces an interference effect between hands. There have been many studies--using varying methods--investigating the development of bimanual movements that show that this skill continues to evolve during childhood and…

  17. Exploring Aging Attitudes through a Puppet Making Research Study

    ERIC Educational Resources Information Center

    Whiteland, Susan R.

    2016-01-01

    Intergenerational programs often reduce ageism and stereotypical thinking. This author uses a mixed methods case study to investigate how attitudes may change when older adults and children participate in an intergenerational art project. The research question, "Is there a positive correlation in children's attitudes toward older adults and…

  18. Heterochronic parabiosis for the study of the effects of aging on stem cells and their niches

    PubMed Central

    Conboy, Irina M.; Rando, Thomas A.

    2012-01-01

    Aging is unmistakable and undeniable in mammals. Interestingly, mice develop cataracts, muscle atrophy, osteoporosis, obesity, diabetes and cognitive deficits after just 2–3 postnatal years, while it takes seven or more decades for the same age-specific phenotypes to develop in humans. Thus, chronological age corresponds differently with biological age in metazoan species and although many theories exist, we do not understand what controls the rate of mammalian aging. One interesting idea is that species-specific rate of aging represents a ratio of tissue attrition to tissue regeneration. Furthermore, current findings suggest that the age-imposed biochemical changes in the niches of tissue stem cells inhibit performance of this regenerative pool, which leads to the decline of tissue maintenance and repair. If true, slowing down stem cell and niche aging, thereby promoting tissue regeneration, could slow down the process of tissue and organismal aging. In this regard, recent studies of heterochronic parabiosis provide important clues as to the mechanisms of stem cell aging and suggest novel strategies for enhancing tissue repair in the old. Here we review current literature on the relationship between the vigor of tissue stem cells and the process of aging, with an emphasis on the rejuvenation of old tissues by the extrinsic modifications of stem cell niches. PMID:22617385

  19. A quantitative study on accumulation of age mass around stagnation points in nested flow systems

    NASA Astrophysics Data System (ADS)

    Jiang, Xiao-Wei; Wan, Li; Ge, Shemin; Cao, Guo-Liang; Hou, Guang-Cai; Hu, Fu-Sheng; Wang, Xu-Sheng; Li, Hailong; Liang, Si-Hai

    2012-12-01

    The stagnant zones in nested flow systems have been assumed to be critical to accumulation of transported matter, such as metallic ions and hydrocarbons in drainage basins. However, little quantitative research has been devoted to prove this assumption. In this paper, the transport of age mass is used as an example to demonstrate that transported matter could accumulate around stagnation points. The spatial distribution of model age is analyzed in a series of drainage basins of different depths. We found that groundwater age has a local or regional maximum value around each stagnation point, which proves the accumulation of age mass. In basins where local, intermediate and regional flow systems are all well developed, the regional maximum groundwater age occurs at the regional stagnation point below the basin valley. This can be attributed to the long travel distances of regional flow systems as well as stagnancy of the water. However, when local flow systems dominate, the maximum groundwater age in the basin can be located around the local stagnation points due to stagnancy, which are far away from the basin valley. A case study is presented to illustrate groundwater flow and age in the Ordos Plateau, northwestern China. The accumulation of age mass around stagnation points is confirmed by tracer age determined by 14C dating in two boreholes and simulated age near local stagnation points under different dispersivities. The results will help shed light on the relationship between groundwater flow and distributions of groundwater age, hydrochemistry, mineral resources, and hydrocarbons in drainage basins.

  20. NAS Parallel Benchmarks, Multi-Zone Versions

    NASA Technical Reports Server (NTRS)

    vanderWijngaart, Rob F.; Haopiang, Jin

    2003-01-01

    We describe an extension of the NAS Parallel Benchmarks (NPB) suite that involves solving the application benchmarks LU, BT and SP on collections of loosely coupled discretization meshes. The solutions on the meshes are updated independently, but after each time step they exchange boundary value information. This strategy, which is common among structured-mesh production flow solver codes in use at NASA Ames and elsewhere, provides relatively easily exploitable coarse-grain parallelism between meshes. Since the individual application benchmarks also allow fine-grain parallelism themselves, this NPB extension, named NPB Multi-Zone (NPB-MZ), is a good candidate for testing hybrid and multi-level parallelization tools and strategies.

  1. The Relationship of Korean Students' Age and Years of English-as-a-Foreign-Language Exposure with English-Reading Ability: A Cross-Age Study

    ERIC Educational Resources Information Center

    Fitzgerald, Jill; Stenner, A. Jackson; Sanford-Moore, Eleanor E.; Koons, Heather; Bowen, Kimberly; Kim, Kee Hyung

    2015-01-01

    The purpose of the present cross-age study with South Korean students was to investigate the relationship of age and years of English-as-a-foreign-language (EFL) exposure with English-reading ability. The main research question was, "Do individuals' age and number of years of English exposure interact in relation to English-reading…

  2. Auxiliary feedwater system aging study. Volume 2, Phase 1: Follow-on study

    SciTech Connect

    Kueck, J.D.

    1993-07-01

    This report documents the results of a Phase I follow-on study of the Auxiliary Feedwater (AFW) System that has been conducted for the US Regulatory Commission`s Nuclear Plant Aging research Program. The Phase I study found a number of significant AFW System functions that are not being adequately tested by conventional test methods and some that are actually being degraded by conventional testing. Thus, it was decided that this follow-on study would focus on these testing omissions nd equipment degradation. The deficiencies in current monitoring and operating practice are categorized and evaluated. Areas of component degradation caused by current practice are discussed. Recommendations are made for improved diagnostic methods and test procedures.

  3. Study of cnidarian-algal symbiosis in the "omics" age.

    PubMed

    Meyer, Eli; Weis, Virginia M

    2012-08-01

    The symbiotic associations between cnidarians and dinoflagellate algae (Symbiodinium) support productive and diverse ecosystems in coral reefs. Many aspects of this association, including the mechanistic basis of host-symbiont recognition and metabolic interaction, remain poorly understood. The first completed genome sequence for a symbiotic anthozoan is now available (the coral Acropora digitifera), and extensive expressed sequence tag resources are available for a variety of other symbiotic corals and anemones. These resources make it possible to profile gene expression, protein abundance, and protein localization associated with the symbiotic state. Here we review the history of "omics" studies of cnidarian-algal symbiosis and the current availability of sequence resources for corals and anemones, identifying genes putatively involved in symbiosis across 10 anthozoan species. The public availability of candidate symbiosis-associated genes leaves the field of cnidarian-algal symbiosis poised for in-depth comparative studies of sequence diversity and gene expression and for targeted functional studies of genes associated with symbiosis. Reviewing the progress to date suggests directions for future investigations of cnidarian-algal symbiosis that include (i) sequencing of Symbiodinium, (ii) proteomic analysis of the symbiosome membrane complex, (iii) glycomic analysis of Symbiodinium cell surfaces, and (iv) expression profiling of the gastrodermal cells hosting Symbiodinium.

  4. Selective effects of aging on brain white matter microstructure: a diffusion tensor imaging tractography study.

    PubMed

    Michielse, Stijn; Coupland, Nick; Camicioli, Richard; Carter, Rawle; Seres, Peter; Sabino, Jennifer; Malykhin, Nikolai

    2010-10-01

    We examined age-related changes in the cerebral white matter. Structural magnetic resonance images (MRIs) and diffusion tensor images (DTIs) were acquired from 69 healthy subjects aged 22-84 years. Quantitative DTI tractography was performed for nine different white matter tracts to determine tract volume, fractional anisotropy (FA), mean diffusivity (MD), axial, and radial diffusivities. We used automated and manual segmentation to determine volumes of gray matter (GM), white mater (WM), cerebrospinal fluid (CSF), and intracranial space. The results showed significant effects of aging on WM, GM, CSF volumes, and selective effects of aging on structural integrity of different white matter tracts. WM of the prefrontal region was the most vulnerable to aging, while temporal lobe connections, cingulum, and parieto-occipital commissural connections showed relative preservation with age. This study was cross-sectional, and therefore, additional longitudinal studies are needed to confirm our findings.

  5. Accuracy of age estimation methods from orthopantomograph in forensic odontology: a comparative study.

    PubMed

    Khorate, Manisha M; Dinkar, A D; Ahmed, Junaid

    2014-01-01

    Changes related to chronological age are seen in both hard and soft tissue. A number of methods for age estimation have been proposed which can be classified in four categories, namely, clinical, radiological, histological and chemical analysis. In forensic odontology, age estimation based on tooth development is universally accepted method. The panoramic radiographs of 500 healthy Goan, Indian children (250 boys and 250 girls) aged between 4 and 22.1 years were selected. Modified Demirjian's method (1973/2004), Acharya AB formula (2011), Dr Ajit D. Dinkar (1984) regression equation, Foti and coworkers (2003) formula (clinical and radiological) were applied for estimation of age. The result of our study has shown that Dr Ajit D. Dinkar method is more accurate followed by Acharya Indian-specific formula. Furthermore, in this study by applying all these methods to one regional population, we have attempted to present dental age estimation methodology best suited for the Goan Indian population.

  6. Remote access for NAS: Supercomputing in a university environment

    NASA Technical Reports Server (NTRS)

    Johnson, G.; Olson, B.; Swisshelm, J.; Pryor, D.; Ziebarth, J.

    1986-01-01

    The experiment was designed to assist the Numerical Aerodynamic Simulation (NAS) Project Office in the testing and evaluation of long haul communications for remote users. The objectives of this work were to: (1) use foreign workstations to remotely access the NAS system; (2) provide NAS with a link to a large university-based computing facility which can serve as a model for a regional node of the Long-Haul Communications Subsystem (LHCS); and (3) provide a tail circuit to the University of Colorado a Boulder thereby simulating the complete communications path from NAS through a regional node to an end-user.

  7. Antecedents of Intact Cognition and Dementia at Age 90: A Prospective Study

    PubMed Central

    Vaillant, George E.; Okereke, Olivia I; Mukamal, Kenneth; Waldinger, Robert J.

    2014-01-01

    Objectives To examine the possible antecedents of both dementia and sustained intact cognition at age 90 among men who underwent a prospective, multidisciplinary assessment from age 19 to 90, with little attrition. Methods A prospective 20-year reassessment of the 196 (out of 268) former Harvard College sophomores who survived until age 70. Begun in 1939 the Study gathered measurements of childhood environment, dominant personality traits, and objective mental and physical health over time, smoking in pack years, alcohol abuse and depression. Questionnaires were obtained every two years and physical exams every five years. Cognitive status was assessed at ages 80, 85 and 90. Results Despite addressing a wide variety health, behavioral and social factors over the lifespan, we observed few predictors with strong association with either intact cognition at age 90 (n = 40) or dementia (n = 44). Univariate analysis revealed seven suggestive predictors of intact cognition at age 90 or of dementia: warm childhood relationship with mother, exercise at age 60, high maternal education, young age of mother at subject’s birth, low BMI, good physical health at 60, and late retirement. Only the first 3 variables: warm childhood relationship with mother, exercise at age 60, and high maternal education remained significant with logistic regression. Conclusions In this prospective study of long-lived, highly educated men several well-known putative predictors of AD did not distinguish those who over the next 20 years developed dementia from those with unimpaired cognition until age 90. PMID:24733646

  8. Sexual dimorphism of facial appearance in ageing human adults: A cross-sectional study.

    PubMed

    Mydlová, Miriama; Dupej, Ján; Koudelová, Jana; Velemínská, Jana

    2015-12-01

    In the forensic sciences, knowledge of facial ageing is very important in searching for both dead and living individuals. Ageing estimations typically model the biological profile, which can be compared to missing persons. The main goals of this current study were to construct ageing trajectories for adult human faces of both sexes and evaluate sexual dimorphism in relation to static allometry. Our study was based on the analysis of three-dimensional facial surface models of 194 individuals 20-80 years of age. The evaluation consisted of a dense correspondence analysis of facial scans and multivariate statistics. It was shown that both age and sex have a significant influence on facial form and shape. Male features included a longer face, with more protruded foreheads, eyebrow ridges and nose, including the region under the upper lip and mandible region, but more retruded cheeks compared to females. Ageing in both sexes shared common traits, such as more pronounced roundness of the face (rectangular in males), decreased facial convexity, increased visibility of skin folds and wrinkles connected with the loss of skin elasticity, and soft tissue stretching, especially in the orbital area and lower face; however, male faces exhibited more intense ageing changes. The above-mentioned sexual dimorphic traits tended to diminish in the elderly age category, though overall sexual dimorphism was heightened with age. The static allometric relationships between size and form or shape were similar in both sexes, except that the larger faces of elderly males displayed more intensive ageing changes.

  9. Dissecting mechanisms of brain aging by studying the intrinsic excitability of neurons

    PubMed Central

    Rizzo, Valerio; Richman, Jeffrey; Puthanveettil, Sathyanarayanan V.

    2015-01-01

    Several studies using vertebrate and invertebrate animal models have shown aging associated changes in brain function. Importantly, changes in soma size, loss or regression of dendrites and dendritic spines and alterations in the expression of neurotransmitter receptors in specific neurons were described. Despite this understanding, how aging impacts intrinsic properties of individual neurons or circuits that govern a defined behavior is yet to be determined. Here we discuss current understanding of specific electrophysiological changes in individual neurons and circuits during aging. PMID:25610394

  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. M31AGES: Studying the intermediate-aged populations in the satellites, smooth halo, and substructure of Andromeda

    NASA Astrophysics Data System (ADS)

    Hamren, Katherine; Beaton, Rachael; Guhathakurta, Puragra; Majewski, Steven R.; M31AGES Survey Team

    2016-01-01

    Recent large-scale surveys of M31 have enabled the study of its satellites, smooth halo, and substructure in exquisite detail. In particular, the Spectroscopic Landscape of Andromeda's Stellar Halo (SPLASH) survey has obtained moderate resolution optical spectra with the DEIMOS spectrograph on the Keck II/10-m telescope, and optical photometry from various ground-based telescopes. These data have been used to map the kinematics and metallicity distributions in the dSphs and dEs, detect and characterize substructure, and study the large-scale radial surface brightness and metallicity profiles of the "smooth" halo. Notwithstanding this progress [or] In spite of these advances, there are a number of outstanding questions that cannot be answered with these data alone, including the fraction of the halo that was formed in situ vs by accretion, and the degeneracy between massive early accretion events and less massiverecent accretion events. The M31 Asymptotic Giant Extended Survey (M31AGES) aims to address these questions by using NIR photometry to identify intermediate-age AGB stars in the satellites, streams, and smoothhalo of M31. We present the details of the observations (now completed), the plan for public release of data products, and preliminary results.

  12. The applicability of Willems' method for age estimation in southern Turkish children: A preliminary study.

    PubMed

    Onat Altan, Halenur; Altan, Ahmet; Bilgiç, Fundagül; Akıncı Sözer, Özlem; Damlar, İbrahim

    2016-02-01

    The aims of the present study were to evaluate the applicability and accuracy of Willems' method for assessing southern Turkish children and to analyze the practicability of this method in different age groups for both genders. Panoramic radiographs of 756 children (378 females, 378 males) aged between 5 and 14.99 years were examined by one observer. This retrospective study involved a contemporary southern Turkish population. The chronological ages of the subjects were divided into 10 groups. These 10 groups consisted of children of the following ages 5 and 14.99. Relationships between continuous variables were examined using Pearson's correlation coefficient. The paired t-test was used to compare all data according to gender and age groups. A p-value of less than 0.05 was considered significant for all statistical data. According to the results, a very high correlation was found for both girls (r(2) = 0.946) and for boys (r(2) = 0.940). Dental age (DA) and chronological age (CA) were consistent for girls in the four age groups (5-5.99, 6-6.99, 12-12.99, and 14-14.99) and for boys in the three age groups (5-5.99,13-13.99, 14-14.99). The maturity score of Willems' Belgian samples of the DA was applicable to seven groups of the southern Turkish children. The present study reports that Willems' method is more accurate for girls than for boys.

  13. Aging and DNA damage in humans: a meta-analysis study

    PubMed Central

    Soares, Jorge Pinto; Cortinhas, António; Bento, Teresa; Leitão, José Carlos; Collins, Andrew R.; Gaivã, Isabel; Mota, Maria Paula

    2014-01-01

    Age-related DNA damage is regarded as one of the possible explanations of aging. Although a generalized idea about the accumulation of DNA damage with age exists, results found in the literature are inconsistent. To better understand the question of age-related DNA damage in humans and to identify possible moderator variables, a meta-analysis was conducted. Electronic databases and bibliographies for studies published since 2004 were searched. Summary odds ratios (ORs) and 95% confidence intervals (CIs) for age-related DNA damage were calculated in a random-effects model. A total of 76 correlations from 36 studies with 4676 participants were included. Based on our analysis, a correlation between age and DNA damage was found (r = 0.230, p = 0.000; 95% confidence interval = 0.111 - 0.342). The test for heterogeneity of variance indicates that the study´s results are significantly high (Q (75) = 1754.831, p = 0.000). Moderator variables such as smoking habits, technique used, and the tissue/sample analyzed, are shown to influence age-related DNA damage (p=0.026; p=0.000; p=0.000, respectively). Nevertheless, sex did not show any influence on this relation (p=0.114). In conclusion, this meta-analysis showed an association between age and DNA damage in humans. It was also found that smoking habits, the technique used, and tissue/sample analyzed, are important moderator variables in age-related DNA damage. PMID:25140379

  14. An Evaluation of the NaS Battery Storage Potential for Providing Regulation Service in California

    SciTech Connect

    Lu, Ning; Weimar, Mark R.; Makarov, Yuri V.; Loutan, Clyde

    2011-03-23

    Sodium sulfur (NaS) batteries can provide energy storage, real-time dispatch, regulation, frequency response, and other essential services to the power grids. This study presents the technical characteristics, modeling approach, methodologies, and results for providing regulation services in the California Independent System Operator (CAISO) market. Two different scenarios were studied and compared: a scenario without intermittent renewable-energy resource penetration (base case) and a scenario with significant renewable-energy resource penetration (including wind) reaching 20% of CAISO’s energy supply. In addition, breakeven cost analyses were developed for four cases. Based on the results of the technical and cost analyses, the opportunities for the NaS battery providing the regulation services are discussed, design improvements for the battery’s physical characteristics are recommended, and modifications of the regulation signals sent to NaS batteries are proposed.

  15. Active ear acupuncture points in neonates with neonatal abstinence syndrome (NAS).

    PubMed

    Raith, Wolfgang; Kutschera, Jörg; Müller, Wilhelm; Urlesberger, Berndt

    2011-01-01

    The aim of the study was to determine the presence of acupuncture ear points in neonates with Neonatal Abstinence Syndrome (NAS). NAS occurs in the first days of life in neonates whose mothers have a history of drug abuse, and may also occur in neonates whose mothers are currently following substitution therapy. The patients are neonates with NAS admitted over one year to the Division of Neonatology at the University Hospital Graz. The examination took place on the third day after delivery (mean value 70.3 hours) and was performed by a neuronal pen (PS 3 © Silberbauer, Vienna, Austria). An integrated sound and optical signal detected the active ear points that were then placed on an ear map. We investigated six neonates (four male, two female). All investigated neonates showed the presence of active ear acupuncture points. The psychovegetative rim was the most common organic area of the children, following by a few organic points. This corresponds with the results found in healthy neonates. In all neonates with NAS, we found the presence of psychic ear points. The identified psychic ear points are the frustration-point, R-point and the psychotropic area nasal from the incisura intertragica. In all neonates with NAS, active organic and psychic ear points were detectable in both ears. In the future, it could be possible to use active ear points for diagnostic and therapeutic purposes.

  16. Polymer Filler Aging and Failure Studied by Lateral Force Microscopy

    SciTech Connect

    Ratto, T; Saab, A P

    2009-05-27

    In the present work, we study, via force microscopy, the basic physical interactions of a single bead of silica filler with a PDMS matrix both before and after exposure to gamma radiation. Our goal was to confirm our results from last year, and to explore force microscopy as a means of obtaining particle-scale polymer/filler interactions suitable for use as empirical inputs to a computational model consisting of an ensemble of silica beads embedded in a PDMS matrix. Through careful calibration of a conventional atomic force microscope, we obtained both normal and lateral force data that was fitted to yield adhesion, surface shear modulus, and friction of a 1 {micro}m silica bead in contact with PDMS layers of various thickness. Comparison of these terms before and after gamma exposure indicated that initially, radiation exposure lead to softening of the PDMS, but eventually resulted in stiffening. Simultaneously, adhesion between the polymer and silica decreased. This could indicate a serious failure path for filled PDMS exposed to radiation, whereby stiffening of the bulk polymer leads to loss of compressive elastic behavior, while a decrease in polymer filler adhesion results in an increased likelihood of stress failure under load. In addition to further testing of radiation damaged polymers, we also performed FEA modeling of silica beads in a silicone matrix using the shear modulus and adhesion values isolated from the force microscopy experiments as model inputs. The resulting simulation indicated that as a polymer stiffens due to impinging radiation, it also undergoes weakening of adhesion to the filler. The implication is that radiation induces a compound failure mode in filled polymer systems.

  17. The Trouble with Isochrone Ages for Field Stars: A Cautionary Tale for Solar Neighbourhood Studies

    NASA Astrophysics Data System (ADS)

    Pont, F.; Eyer, L.

    2005-01-01

    Computing ages from theoretical isochrones for large numbers of field dwarfs is becoming standard practice to study the history of the Galaxy from the solar neighbourhood record. Ages are usually read off the nearest model isochrone in parameter space. In the wake of the publication of the Geneva-Copenhagen Solar Neighbourhood Survey, we have reconsidered the isochrone age method. We find that isochrone ages for field dwarfs are subject to enormous systematic biases, and simple analysis methods e.g., scatter plots, are not appropriate. More evolved statistical treatments are essential for meaningful results (Bayesian estimates, inverse approach).

  18. Hippocampus age-related microstructural changes in schizophrenia: a case-control mean diffusivity study.

    PubMed

    Chiapponi, Chiara; Piras, Fabrizio; Fagioli, Sabrina; Girardi, Paolo; Caltagirone, Carlo; Spalletta, Gianfranco

    2014-08-01

    Macrostructural-volumetric abnormalities of the hippocampus have been described in schizophrenia. Here, we characterized age-related changes of hippocampal mean diffusivity as an index of microstructural damage by carrying out a neuroimaging study in 85 patients with a DSM-IV-TR diagnosis of schizophrenia and 85 age- and gender-matched healthy controls. We performed analyses of covariance, with diagnosis as fixed factor, mean diffusivity as dependent variable and age as covariate. Patients showed an early increase in mean diffusivity in the right and left hippocampus that increased with age. Thus, microstructural hippocampal changes associated with schizophrenia cannot be confined to a specific time window.

  19. Gestational Age at Birth and 'Body-Mind' Health at 5 Years of Age: A Population Based Cohort Study.

    PubMed

    Cronin, Frances M; Segurado, Ricardo; McAuliffe, Fionnuala M; Kelleher, Cecily C; Tremblay, Richard E

    2016-01-01

    Numerous studies have identified the effects of prematurity on the neonate's physical health, however few studies have explored the effects of prematurity on both the physical and mental health of the child as they develop. Secondary analysis of data from the Millennium Cohort Study, a longitudinal study of infants (n = 18 818, born 2000-2002 in the United Kingdom) was performed. Effects of gestational age at birth on health outcomes at 5 years were measured using parental rating of their children's general health and severity of behavior problems. The association between parent's general health ratings and behavior problem ratings was low: 86% of those reporting serious behavior problems (5% of the sample, n = 764) rated their child as being in excellent, very good, or good health. Still, a gradient of increasing risk of poorer outcome with decreasing gestational age was observed for a composite health measure (poor/fair health and/or serious behavior problems), suggesting an association with prematurity for this composite assessment of health status. The greatest contribution to the childhood composite health measure at 5 years was for children born at 32-36 weeks gestation: population attributable fractions for having poor outcomes was 3.4% (Bonferroni-adjusted 95% confidence interval 1.1%-6.2%), compared to 1% (0.2-2.3) for birth at less than 32 weeks. Results suggest that preterm children, by school entry, are not only at high risk of physical health problems, but also of behavioral health problems. The recognition of, and response to comprehensive health and well-being outcomes related to prematurity are important in order to correctly plan and deliver adequate paediatric health services and policies.

  20. Gestational Age at Birth and ‘Body-Mind’ Health at 5 Years of Age: A Population Based Cohort Study

    PubMed Central

    Segurado, Ricardo; McAuliffe, Fionnuala M.; Kelleher, Cecily C.

    2016-01-01

    Numerous studies have identified the effects of prematurity on the neonate’s physical health, however few studies have explored the effects of prematurity on both the physical and mental health of the child as they develop. Secondary analysis of data from the Millennium Cohort Study, a longitudinal study of infants (n = 18 818, born 2000–2002 in the United Kingdom) was performed. Effects of gestational age at birth on health outcomes at 5 years were measured using parental rating of their children’s general health and severity of behavior problems. The association between parent’s general health ratings and behavior problem ratings was low: 86% of those reporting serious behavior problems (5% of the sample, n = 764) rated their child as being in excellent, very good, or good health. Still, a gradient of increasing risk of poorer outcome with decreasing gestational age was observed for a composite health measure (poor/fair health and/or serious behavior problems), suggesting an association with prematurity for this composite assessment of health status. The greatest contribution to the childhood composite health measure at 5 years was for children born at 32–36 weeks gestation: population attributable fractions for having poor outcomes was 3.4% (Bonferroni-adjusted 95% confidence interval 1.1%–6.2%), compared to 1% (0.2–2.3) for birth at less than 32 weeks. Results suggest that preterm children, by school entry, are not only at high risk of physical health problems, but also of behavioral health problems. The recognition of, and response to comprehensive health and well-being outcomes related to prematurity are important in order to correctly plan and deliver adequate paediatric health services and policies. PMID:26975048

  1. A study of aged population and associated health risks in rural India.

    PubMed

    Yadava, K N; Yadava, S S; Vajpeyi, D K

    1997-01-01

    This article examines the prevalence of age-related diseases in different socioeconomic and demographic groups. The study is based on a sample of 267 aged persons (> 60 years) collected through a survey entitled "Aging and Health Conditions in Rural Area-A Sample Survey, 1990" conducted in the rural areas of the Varanasi district of Uttar Pradesh, a northern province of India. Various socio-behavioral factors are found to play a significant role in determining the health conditions of aged people. Also, illiteracy and poverty are found to have their own impact on health during aging. It is also noted that due to adverse familial relationships, many stress-related disorders occur which may result in the poor health of the elderly. Demands for old age pensions were made by most of the elderly people in the sample.

  2. Aging of nuclear station diesel generators: Evaluation of operating and expert experience: Phase 1, Study

    SciTech Connect

    Hoopingarner, K.R.; Vause, J.W.; Dingee, D.A.; Nesbitt, J.F.

    1987-08-01

    Pacific Northwest Laboratory evaluated operational and expert experience pertaining to the aging degradation of diesel generators in nuclear service. The research, sponsored by the US Nuclear Regulatory Commission (NRC), identified and characterized the contribution of aging to emergency diesel generator failures. This report, Volume I, reviews diesel-generator experience to identify the systems and components most subject to aging degradation and isolates the major causes of failure that may affect future operational readiness. Evaluations show that as plants age, the percent of aging-related failures increases and failure modes change. A compilation is presented of recommended corrective actions for the failures identified. This study also includes a review of current, relevant industry programs, research, and standards. Volume II reports the results of an industry-wide workshop held on May 28 and 29, 1986 to discuss the technical issues associated with aging of nuclear service emergency diesel generators.

  3. Effect of locally delivered IGF-1 on nerve regeneration during aging: an experimental study in rats.

    PubMed

    Apel, Peter J; Ma, Jianjun; Callahan, Michael; Northam, Casey N; Alton, Timothy B; Sonntag, William E; Li, Zhongyu

    2010-03-01

    Age is an important predictor of neuromuscular recovery after peripheral nerve injury. Insulin-like growth factor 1 (IGF-1) is a potent neurotrophic factor that is known to decline with increasing age. The purpose of this study was to determine if locally delivered IGF-1 would improve nerve regeneration and neuromuscular recovery in aged animals. Young and aged rats underwent nerve transection and repair with either saline or IGF-1 continuously delivered to the site of the nerve repair. After 3 months, nerve regeneration and neuromuscular junction morphology were assessed. In both young and aged animals, IGF-1 significantly improved axon number, diameter, and density. IGF-1 also significantly increased myelination and Schwann cell activity and preserved the morphology of the postsynaptic neuromuscular junction (NMJ). These results show that aged regenerating nerve is sensitive to IGF-1 treatment.

  4. Contribution of NIRS to the Study of Prefrontal Cortex for Verbal Fluency in Aging

    ERIC Educational Resources Information Center

    Kahlaoui, Karima; Di Sante, Gabriele; Barbeau, Joannie; Maheux, Manon; Lesage, Frederic; Ska, Bernadette; Joanette, Yves

    2012-01-01

    Healthy aging is characterized by a number of changes on brain structure and function. Several neuroimaging studies have shown an age-related reduction in hemispheric asymmetry on various cognitive tasks, a phenomenon captured by Cabeza (2002) in the Hemispheric Asymmetry Reduction in Older Adults (HAROLD) model. Although this phenomenon is…

  5. A Twin-Study of Sleep Difficulties in School-Aged Children

    ERIC Educational Resources Information Center

    Gregory, Alice M.; Rijsdijk, Fruhling V.; Eley, Thalia C.

    2006-01-01

    This study examines frequency, overlap, and genetic and environmental influences on sleep difficulties, which are understudied in school-aged children. The Sleep Self Report and the Children's Sleep Habits Questionnaire were completed by 300 twin pairs (aged 8 years) and their parents. Child report suggested more frequent sleep problems than…

  6. A Pilot Study of Urinary Peptides as Biomarkers for Intelligence in Old Age

    ERIC Educational Resources Information Center

    Lopez, Lorna M.; Mullen, William; Zurbig, Petra; Harris, Sarah E.; Gow, Alan J.; Starr, John M.; Porteous, David J.; Mischak, Harald; Deary, Ian J.

    2011-01-01

    Intelligence is an important indicator of physical, mental and social well-being. In old age, intelligence is also associated with a higher quality of life and better health. Heritability studies have shown that there are strong genetic influences, yet unknown, on intelligence, including in old age. Other approaches may be useful to investigate…

  7. Data resource profile: the World Health Organization Study on global AGEing and adult health (SAGE).

    PubMed

    Kowal, Paul; Chatterji, Somnath; Naidoo, Nirmala; Biritwum, Richard; Fan, Wu; Lopez Ridaura, Ruy; Maximova, Tamara; Arokiasamy, Perianayagam; Phaswana-Mafuya, Nancy; Williams, Sharon; Snodgrass, J Josh; Minicuci, Nadia; D'Este, Catherine; Peltzer, Karl; Boerma, J Ties

    2012-12-01

    Population ageing is rapidly becoming a global issue and will have a major impact on health policies and programmes. The World Health Organization's Study on global AGEing and adult health (SAGE) aims to address the gap in reliable data and scientific knowledge on ageing and health in low- and middle-income countries. SAGE is a longitudinal study with nationally representative samples of persons aged 50+ years in China, Ghana, India, Mexico, Russia and South Africa, with a smaller sample of adults aged 18-49 years in each country for comparisons. Instruments are compatible with other large high-income country longitudinal ageing studies. Wave 1 was conducted during 2007-2010 and included a total of 34 124 respondents aged 50+ and 8340 aged 18-49. In four countries, a subsample consisting of 8160 respondents participated in Wave 1 and the 2002/04 World Health Survey (referred to as SAGE Wave 0). Wave 2 data collection will start in 2012/13, following up all Wave 1 respondents. Wave 3 is planned for 2014/15. SAGE is committed to the public release of study instruments, protocols and meta- and micro-data: access is provided upon completion of a Users Agreement available through WHO's SAGE website (www.who.int/healthinfo/systems/sage) and WHO's archive using the National Data Archive application (http://apps.who.int/healthinfo/systems/surveydata).

  8. 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

  9. Exercise induces age-dependent changes on epigenetic parameters in rat hippocampus: a preliminary study.

    PubMed

    Elsner, Viviane Rostirola; Lovatel, Gisele Agustini; Moysés, Felipe; Bertoldi, Karine; Spindler, Christiano; Cechinel, Laura Reck; Muotri, Alysson Renato; Siqueira, Ionara Rodrigues

    2013-02-01

    Regular exercise improves learning and memory, including during aging process. Interestingly, the imbalance of epigenetic mechanisms has been linked to age-related cognitive deficits. However, studies about epigenetic alterations after exercise during the aging process are rare. In this preliminary study we investigated the effect of aging and exercise on DNA methyltransferases (DNMT1 and DNMT3b) and H3-K9 methylation levels in hippocampus from 3 and 20-months aged Wistar rats. The animals were submitted to two exercise protocols: single session or chronic treadmill protocol. DNMT1 and H3-K9 methylation levels were decreased in hippocampus from aged rats. The single exercise session decreased both DNMT3b and DNMT1 levels in young adult rats, without any effect in the aged group. Both exercise protocols reduced H3-K9 methylation levels in young adult rats, while the single session reversed the changes on H3-K9 methylation levels induced by aging. Together, these results suggest that an imbalance on DNMTs and H3-K9 methylation levels might be linked to the brain aging process and that the outcome to exercise seems to vary through lifespan.

  10. 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.

  11. Cannabis use, gender and age of onset of schizophrenia: data from the ÆSOP study.

    PubMed

    Donoghue, Kim; Doody, Gillian A; Murray, Robin M; Jones, Peter B; Morgan, Craig; Dazzan, Paola; Hart, Jozella; Mazzoncini, Rodolfo; Maccabe, James H

    2014-03-30

    An earlier age of onset of schizophrenia has been identified as a poor prognostic indicator. The current study examines the interaction effect of gender and cannabis use on age of onset of schizophrenia and schizoaffective disorder. This research forms part of a two-centre epidemiological study of first-episode psychosis and included individuals with a diagnosis of schizophrenia or schizoaffective disorder and an age of onset between age 16 and 45. Kaplan-Meier curves and Cox proportional hazards regression were used to compare the effects of cannabis use and gender on age of first symptom of schizophrenia. Akaike's information criteria were used to find the model with the best fit to the data. Cannabis users had an earlier age of first symptom than non-users. There was an interaction with gender; the gender difference in age of onset was diminished in cannabis smokers compared with non-cannabis smokers. The model including cannabis use interacting with gender was the most parsimonious model, followed by cannabis use alone. The addition of other illegal drug use did not improve the model. Cannabis use is associated with an earlier age of onset of schizophrenia, and the gender difference in age of onset is reduced among cannabis smokers.

  12. Aging and the Aged in the Third World: Part I. Studies in Third World Societies. Publication Number Twenty-Two.

    ERIC Educational Resources Information Center

    Sutlive, Vinson H., Ed.; And Others

    Problems regarding the aged in developing nations are examined. The aging of populations is now a global phenomenon, with crucial implications for the developing as well as the developed nations. Six articles are presented: "Introduction, Perspectives on Aging in the Third World" (Jay Sokolovsky), "What Can the Industrial World…

  13. [Dementia in the focus of health research : A comparative analysis of current ageing studies].

    PubMed

    Illiger, Kristin; Walter, Ulla; Koppelin, Frauke

    2017-03-23

    Health research on an increasingly aging population calls for careful consideration of aging-associated phenomena, such as dementia. Accounting for such diseases is a necessary step for gaining a view of health in the elderly. It is moreover imperative to gather data on subjects' mental limitations in surveys to better evaluate the validity of answers disclosed by elderly participants. This article discusses the availability of data on individuals suffering from dementia in national studies on aging. It centers on the question of how surveys respond to the challenge of diagnosing dementia. The analysis is based on a literature review, which focuses on national studies on aging that were conducted no later than 2005, and that enforced an upper age limit of at least 79 years old for their subjects. By evaluating these published studies, and analyzing their data descriptively, it was determined how many subjects suffering from dementia were part of each sample, and which methods were applied to diagnose such illnesses. Overall, the availability of data on age and aging is satisfactory in Germany. The literature review discovered seven studies on aging, as well as five that lend themselves to a framework oriented toward research on aging. The number of subjects suffering from dementia in the samples is between 0 and 14% - over half of the studies reach less than 1.5% of those affected. These results thus point out problems in surveying individuals suffering from dementia. They highlight the limitations of studies on aging that do not account for dementia in their subjects. The following discussion aims to contribute to the debate on relevant research methodology, and to the development of methodological approaches that consider dementia as a crucial factor.

  14. Overweight and obesity in young and middle age and early retirement: the ARIC study.

    PubMed

    Houston, Denise K; Cai, Jianwen; Stevens, June

    2009-01-01

    The objective of this study was to examine associations between weight status in young and middle age and early retirement in African-American and white men and women. Data were from the Atherosclerosis Risk in Communities (ARIC) study. Analyses were restricted to participants aged 45-55 years at baseline (n = 6,483). Associations between weight status at age 25 and ages 45-55 and age at early retirement (prior to age 65) over 9 years of follow-up were examined using proportional hazard regression analyses in models stratified by race and gender. Models were adjusted for education, household income, health insurance status, occupation, occupational physical activity, marital status, smoking, and field center. Between 18.7 and 21.6% of African-American and white men and women reported retiring prior to age 65. Although not always statistically significant, overweight and obesity were associated with early retirement in all but white women. Overweight (BMI >or= 25 kg/m(2)) at age 25 was significantly associated with early retirement in African-American women (hazard ratio (95% confidence interval): 1.62 (1.17-2.23)) and white men (1.32 (1.12-1.57)). There was also a trend between overweight at age 25 and early retirement in African-American men (1.43 (0.99-2.07)). Obesity (BMI >or= 30 kg/m(2)) in middle age was significantly associated with early retirement in white men only (1.32 (1.03-1.69)). Furthermore, overweight at age 25 and obesity at ages 45-55 were associated with early retirement for health reasons among African-American and white men and women. In conclusion, analyses of the economic impact of obesity may need to consider its effects on early retirement.

  15. 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

  16. Association Between Age at Menarche and Gestational Diabetes Mellitus: The Australian Longitudinal Study on Women's Health.

    PubMed

    Schoenaker, Danielle A J M; Mishra, Gita D

    2017-03-05

    In this study, we aimed to examine the association between age at menarche and gestational diabetes mellitus (GDM). Data were from 4,749 women participating in the Australian Longitudinal Study on Women's Health between 2000 and 2012. Age at menarche was reported at baseline in 2000 when women were aged 22-27 years. During 12 years of follow-up, information on GDM diagnosis was obtained for each live birth. Log-binomial regression analysis was used to estimate relative risks and 95% confidence intervals. Analyses adjusted for mother's highest completed educational qualification, nulliparity, polycystic ovary syndrome, physical activity, and body mass index. Mean age at menarche was 12.9 years (standard deviation, 1.4). A first diagnosis of GDM was reported by 357 women (7.5%). Compared with women with menarche at age 13 years, women who had their first menstruation at age ≤11 years had a 51% higher risk of developing GDM (95% confidence interval: 1.10, 2.07) after adjustment for GDM risk factors. Our findings indicate that a young age at menarche may identify women at higher risk of GDM. Further prospective studies are needed to confirm our findings and to elucidate the role of early-life exposures in age at menarche and subsequent GDM risk.

  17. Compatibility and accelerated aging study for Li(Si)/FeS/sub 2 thermally activated batteries

    NASA Astrophysics Data System (ADS)

    Mead, J. W.; Searcy, J. Q.; Neiswander, P. N.; Poole, R. L.

    1983-12-01

    Thermally activated batteries using the lithium (silicon) iron disulfide (Li(Si)/FeS2) electrochemical system are used in weapons having a required storage life of 25 years and high reliability. A review of known data revealed no information on the compatibility of Li(Si)/FeS2 with the organic materials used in the system. The compatibility question is studied. Accelerated-aging data on pairs of materials were produced. In addition, a group of production batteries was aged and tested. Three aging temperatures were used during the one-year study. Gas analyses, electrical tests and mechanical tests were compared for control and aged samples. Two results, the depletion of oxygen and an increase in hydrogen in the compatibility and accelerated-aging samples, stimulated additional studies. No unexpected or significant changes were observed in the electrical or mechanical properties of the organic materials. Calorific output and chloride ion content of heat pellets indicated no degradation with aging. Ignition sensitivity and burn rate measurements suggested no heat pellet degradation. Oxygen content in aged lithium (silicon) anodes remained within acceptable limits. Single-cell tests and battery test results showed no degradation with aging.

  18. Whether age of menarche is influenced by body mass index and lipoproteins profile? a retrospective study

    PubMed Central

    Farahmand, Maryam; Ramezani Tehrani, Fahimeh; Azizi, Fereidoun

    2012-01-01

    Background: Menarche, a milestone in the reproductive life span of a woman, is influenced by several genetics and environmental factors. There is no consensus regarding the impact of body mass index (BMI) and lipid profiles on the age of menarche, as the results of various studies demonstrate. Objective: To investigate the correlation between age of menarche and BMI/lipoprotein profile in a community sample of Iranian girls. Materials and Methods: In the study, 370 girls, aged 10-16 years, who began their menarche within six months prior to the study, were recruited from the Tehran Lipid and Glucose Study (TLGS) population. Information was documented regarding their body composition, including height, weight, BMI, waist and hip circumference were collected and their lipid profiles were assessed after a 12-hour fast. Results: In this study, the mean±SD of age of menarche and BMI were 12.6±1.1 years and 21.7±3.9 kg/m2, respectively. There were statistically significant relationships between age of menarche and height, BMI, waist circumference, and the maternal educational level. The relationship between age of menarche and the weight and lipid profiles of subjects was not statistically significant. Conclusion: Age at menarche is not influenced by lipid profiles but it is influenced by BMI. PMID:25246895

  19. Mortality Measurement at Advanced Ages: A Study of the Social Security Administration Death Master File.

    PubMed

    Gavrilov, Leonid A; Gavrilova, Natalia S

    2011-01-01

    Accurate estimates of mortality at advanced ages are essential to improving forecasts of mortality and the population size of the oldest old age group. However, estimation of hazard rates at extremely old ages poses serious challenges to researchers: (1) The observed mortality deceleration may be at least partially an artifact of mixing different birth cohorts with different mortality (heterogeneity effect); (2) standard assumptions of hazard rate estimates may be invalid when risk of death is extremely high at old ages and (3) ages of very old people may be exaggerated. One way of obtaining estimates of mortality at extreme ages is to pool together international records of persons surviving to extreme ages with subsequent efforts of strict age validation. This approach helps researchers to resolve the third of the above-mentioned problems but does not resolve the first two problems because of inevitable data heterogeneity when data for people belonging to different birth cohorts and countries are pooled together. In this paper we propose an alternative approach, which gives an opportunity to resolve the first two problems by compiling data for more homogeneous single-year birth cohorts with hazard rates measured at narrow (monthly) age intervals. Possible ways of resolving the third problem of hazard rate estimation are elaborated. This approach is based on data from the Social Security Administration Death Master File (DMF). Some birth cohorts covered by DMF could be studied by the method of extinct generations. Availability of month of birth and month of death information provides a unique opportunity to obtain hazard rate estimates for every month of age. Study of several single-year extinct birth cohorts shows that mortality trajectory at advanced ages follows the Gompertz law up to the ages 102-105 years without a noticeable deceleration. Earlier reports of mortality deceleration (deviation of mortality from the Gompertz law) at ages below 100 appear to be

  20. In vitro 3-D model based on extending time of culture for studying chronological epidermis aging.

    PubMed

    Dos Santos, Morgan; Metral, Elodie; Boher, Aurélie; Rousselle, Patricia; Thepot, Amélie; Damour, Odile

    2015-09-01

    Skin aging is a complex phenomenon in which several mechanisms operate simultaneously. Among them, intrinsic aging is a time-dependent process, which leads to gradual skin changes affecting its structure and function such as thinning down of both epidermal and dermal compartments and a flattening and fragility of the dermo-epidermal junction. Today, several approaches have been proposed for the generation of aged skin in vitro, including skin explants from aged donors and three-dimensional skin equivalent treated by aging-inducing chemical compounds or engineered with human cells isolated from aged donors. The aim of this study was to develop and validate a new in vitro model of aging based on skin equivalent demonstrating the same phenotypic changes that were observed in chronological aging. By using prolonged culture as a proxy for cellular aging, we extended to 120 days the culture time of a skin equivalent model based on collagen-glycosaminoglycan-chitosan porous polymer and engineered with human skin cells from photo-protected sites of young donors. Morphological, immunohistological and ultrastructural analysis at different time points of the culture allowed characterizing the phenotypic changes observed in our model in comparison to samples of non photo-exposed normal human skin from different ages. We firstly confirmed that long-term cultured skin equivalents are still morphologically consistent and functionally active even after 120 days of culture. However, similar to in vivo chronological skin aging a significant decrease of the epidermis thickness as well as the number of keratinocyte expressing proliferation marker Ki67 are observed in extended culture time skin equivalent. Epidermal differentiation markers loricrin, filaggrin, involucrin and transglutaminase, also strongly decreased. Ultrastructural analysis of basement membrane showed typical features of aged skin such as duplication of lamina densa and alterations of hemidesmosomes. Moreover, the

  1. Mortality Measurement at Advanced Ages: A Study of the Social Security Administration Death Master File

    PubMed Central

    Gavrilov, Leonid A.; Gavrilova, Natalia S.

    2011-01-01

    Accurate estimates of mortality at advanced ages are essential to improving forecasts of mortality and the population size of the oldest old age group. However, estimation of hazard rates at extremely old ages poses serious challenges to researchers: (1) The observed mortality deceleration may be at least partially an artifact of mixing different birth cohorts with different mortality (heterogeneity effect); (2) standard assumptions of hazard rate estimates may be invalid when risk of death is extremely high at old ages and (3) ages of very old people may be exaggerated. One way of obtaining estimates of mortality at extreme ages is to pool together international records of persons surviving to extreme ages with subsequent efforts of strict age validation. This approach helps researchers to resolve the third of the above-mentioned problems but does not resolve the first two problems because of inevitable data heterogeneity when data for people belonging to different birth cohorts and countries are pooled together. In this paper we propose an alternative approach, which gives an opportunity to resolve the first two problems by compiling data for more homogeneous single-year birth cohorts with hazard rates measured at narrow (monthly) age intervals. Possible ways of resolving the third problem of hazard rate estimation are elaborated. This approach is based on data from the Social Security Administration Death Master File (DMF). Some birth cohorts covered by DMF could be studied by the method of extinct generations. Availability of month of birth and month of death information provides a unique opportunity to obtain hazard rate estimates for every month of age. Study of several single-year extinct birth cohorts shows that mortality trajectory at advanced ages follows the Gompertz law up to the ages 102–105 years without a noticeable deceleration. Earlier reports of mortality deceleration (deviation of mortality from the Gompertz law) at ages below 100 appear to be

  2. Dietary anthocyanin intake and age-related decline in lung function: longitudinal findings from the VA Normative Aging Study123

    PubMed Central

    Mehta, Amar J; Cassidy, Aedín; Litonjua, Augusto A; Sparrow, David; Vokonas, Pantel; Schwartz, Joel

    2016-01-01

    Background: It is unknown whether habitual intake of dietary flavonoids, known for their antioxidative and anti-inflammatory properties, affects longitudinal change in lung function. Objective: We investigated whether different flavonoid subclasses present in the habitual diet were associated with beneficial changes in lung function over time in the elderly. Design: This longitudinal analysis included 839 participants from the VA (Veterans Affairs) Normative Aging Study whose lung function [forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC)] was measured at 2 and up to 5 visits between 1992 and 2008 (n = 2623 measurements). Yearly average intake of major flavonoid subclasses (anthocyanins, flavanones, flavan-3-ols, flavonols, flavones, and polymers) was calculated from food-frequency questionnaires at each visit. We estimated adjusted differences in annual change in lung function associated with each flavonoid subclass, categorized into quartiles, in linear mixed-effects regression models after adjustment for lifestyle and dietary confounders. Results: Strong inverse associations were found between anthocyanin intake and age-related decline in lung function. Independent of dietary and nondietary risk factors, slower rates of FEV1 and FVC decline by 23.6 (95% CI: 16.6, 30.7) and 37.3 (95% CI: 27.8, 46.8) mL/y, respectively, were observed in participants in the fourth quartile of intake compared with participants in the first quartile (P-trend < 0.0001). The protective associations observed for anthocyanin intake were present in both current/former and never smokers. Compared with no or very low intakes, an intake of ≥2 servings of anthocyanin-rich blueberries/wk was associated with slower decline in FEV1 and FVC by 22.5 (95% CI: 10.8, 34.2) and 37.9 (95% CI: 22.1, 53.7) mL/y, respectively. To a lesser extent, higher flavan-3-ol intake was also associated with slower lung function decline. Conclusions: An attenuation of age-related lung function

  3. Health literacy in old age: results of a German cross-sectional study.

    PubMed

    Vogt, Dominique; Schaeffer, Doris; Messer, Melanie; Berens, Eva-Maria; Hurrelmann, Klaus

    2017-03-22

    Health literacy is especially important for older people to maintain or enhance remaining health resources and self-management skills. The aim of the study was to determine the level of health literacy and the association between health literacy, demographic and socio-economic factors in German older adults aged 65 years and above stratified by age group. Health literacy was assessed via computer-assisted personal interviews using HLS-EU-Q47 on a representative sample of the German-speaking population. Descriptive statistics, bivariate analyses and logistic regression modelling stratified by age group were conducted to assess health literacy of 475 respondents aged 65 years and above. Overall, 66.3% of all respondents aged 65 years and above had limited health literacy. Limited health literacy was especially prevalent among respondents above 76 years of age (80.6%). Limited health literacy was associated with financial deprivation (OR: 3.05; 95% CI: 1.99-4.67) and limited functional health literacy (OR: 2.16; 95% CI: 1.29-3.61). Financial deprivation was strongest predictor for limited health literacy in the total sample and stratified by age group. Limited health literacy is a frequent phenomenon in German adults aged 65 years and above. Research on health literacy in old age and the role in health disparities is urgently needed.

  4. Compositional dependence of the band gap in Ga(NAsP) quantum well heterostructures

    SciTech Connect

    Jandieri, K. Ludewig, P.; Wegele, T.; Beyer, A.; Kunert, B.; Springer, P.; Baranovskii, S. D.; Koch, S. W.; Volz, K.; Stolz, W.

    2015-08-14

    We present experimental and theoretical studies of the composition dependence of the direct band gap energy in Ga(NAsP)/GaP quantum well heterostructures grown on either (001) GaP- or Si-substrates. The theoretical description takes into account the band anti-crossing model for the conduction band as well as the modification of the valence subband structure due to the strain resulting from the pseudomorphic epitaxial growth on the respective substrate. The composition dependence of the direct band gap of Ga(NAsP) is obtained for a wide range of nitrogen and phosphorus contents relevant for laser applications on Si-substrate.

  5. The Need for Vendor Source Code at NAS. Revised

    NASA Technical Reports Server (NTRS)

    Carter, Russell; Acheson, Steve; Blaylock, Bruce; Brock, David; Cardo, Nick; Ciotti, Bob; Poston, Alan; Wong, Parkson; Chancellor, Marisa K. (Technical Monitor)

    1997-01-01

    The Numerical Aerodynamic Simulation (NAS) Facility has a long standing practice of maintaining buildable source code for installed hardware. There are two reasons for this: NAS's designated pathfinding role, and the need to maintain a smoothly running operational capacity given the widely diversified nature of the vendor installations. NAS has a need to maintain support capabilities when vendors are not able; diagnose and remedy hardware or software problems where applicable; and to support ongoing system software development activities whether or not the relevant vendors feel support is justified. This note provides an informal history of these activities at NAS, and brings together the general principles that drive the requirement that systems integrated into the NAS environment run binaries built from source code, onsite.

  6. A review of selected longitudinal studies on aging: past findings and future directions.

    PubMed

    Stanziano, Damian C; Whitehurst, Michael; Graham, Patricia; Roos, Bernard A

    2010-10-01

    A review of the 51 longitudinal aging studies currently in the National Institute on Aging Database of Longitudinal Studies was conducted to identify major information gaps and areas for future research. Database information, which included posted study summaries, study details from principal investigators or directors of these projects, and more than 300 recent publications based on the studies, were reviewed to identify significant findings of each study. This review summarizes the main findings and identifies the need for future work within six broad study topics: cognitive function, socioeconomic status, health and physical performance, morbidity and mortality predictors, healthcare costs, and genetics. The percentages of these 51 studies addressing the four most common topics are as follows: cognitive function (44%), health and physical performance (51%), socioeconomic factors (55%), and predictors of morbidity/mortality (63%). Important areas not addressed to any major degree were healthcare costs and genetics. Only two studies reported findings on genetics or epigenetics of human aging, and only a single study reported on associations between aging and financial costs, especially healthcare costs, which have been postulated to be important determinants of care and life quality. The results of this review, together with the specific directions proposed by other investigators with longitudinal study expertise, will inform the strategic planning of future long-term studies of aging.

  7. Age-dependent expression of DNMT1 and DNMT3B in PBMCs from a large European population enrolled in the MARK-AGE study.

    PubMed

    Ciccarone, Fabio; Malavolta, Marco; Calabrese, Roberta; Guastafierro, Tiziana; Bacalini, Maria Giulia; Reale, Anna; Franceschi, Claudio; Capri, Miriam; Hervonen, Antti; Hurme, Mikko; Grubeck-Loebenstein, Beatrix; Koller, Bernhard; Bernhardt, Jürgen; Schӧn, Christiane; Slagboom, P Eline; Toussaint, Olivier; Sikora, Ewa; Gonos, Efstathios S; Breusing, Nicolle; Grune, Tilman; Jansen, Eugène; Dollé, Martijn; Moreno-Villanueva, María; Sindlinger, Thilo; Bürkle, Alexander; Zampieri, Michele; Caiafa, Paola

    2016-08-01

    Aging is associated with alterations in the content and patterns of DNA methylation virtually throughout the entire human lifespan. Reasons for these variations are not well understood. However, several lines of evidence suggest that the epigenetic instability in aging may be traced back to the alteration of the expression of DNA methyltransferases. Here, the association of the expression of DNA methyltransferases DNMT1 and DNMT3B with age has been analysed in the context of the MARK-AGE study, a large-scale cross-sectional study of the European general population. Using peripheral blood mononuclear cells, we assessed the variation of DNMT1 and DNMT3B gene expression in more than two thousand age-stratified women and men (35-75 years) recruited across eight European countries. Significant age-related changes were detected for both transcripts. The level of DNMT1 gradually dropped with aging but this was only observed up to the age of 64 years. By contrast, the expression of DNMT3B decreased linearly with increasing age and this association was particularly evident in females. We next attempted to trace the age-related changes of both transcripts to the influence of different variables that have an impact on changes of their expression in the population, including demographics, dietary and health habits, and clinical parameters. Our results indicate that age affects the expression of DNMT1 and DNMT3B as an almost independent variable in respect of all other variables evaluated.

  8. Early age at menarche and wheezing in adolescence. The 1993 Pelotas (Brazil) birth cohort study

    PubMed Central

    Joseph, Gary; Baptista Menezes, Ana Maria; Wehrmeister, Fernando C.

    2015-01-01

    Objective To evaluate the effect of menarche before 11 years of age on the incidence of wheezing/asthma in girls 11 to 18 years of age. Methods The study sample comprised 1,350 girls from a birth cohort that started in 1993 in the urban area of the city of Pelotas, southern Brazil; this cohort was followed until 18 years of age. We assessed wheezing by the question, “Have you ever had wheezing in the chest at any time in the past?,” from the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Early menarche was defined as occurring before 11 years of age. We estimated the cumulative incidence of wheezing excluding from the analysis all those participants who reported wheezing before age of 11 years. We performed the chi-square test to assess the association between ever wheezing and independent variables. Poisson regression models with robust variance were used to estimate cumulative incidence ratios. Results The average age at menarche in the cohort girls was 12 years (95% CI: 11.1–12.1). The prevalence of early menarche before 11 years of age was 11% (95% CI: 9.7–12.3). The cumulative incidence of wheezing from 11 to 18 years of age was 33.5% (95% CI: 30.9– 36.0). The crude association between ever wheezing in adolescence and early menarche before age 11 was 1.19 (95% CI: 0.96–1.48). After adjusting for early childhood and contemporaneous variables, no significant association for early menarche before 11 years of age and wheezing during adolescence was found (CIR: 1.18; CI95%: 0.93-1.49). Conclusion Early menarche before 11 years of age is not associated with an increased risk of wheezing during adolescence. PMID:26870751

  9. The study on telomere length for age estimation in a Thai population.

    PubMed

    Srettabunjong, Supawon; Satitsri, Saravut; Thongnoppakhun, Wanna; Tirawanchai, Nednapis

    2014-06-01

    Age is one of the key parameters in establishing a physical characteristic profile of an individual. For biological evidence left in crime scenes such as blood, saliva, hair, etc, the evidence owner's age can be determined only by DNA extracted from these materials. Previous researches have found that there are certain DNA regions with specialized characteristic and function called telomere being able to predict age. The present study was to determine the correlation between telomere length and age as well as the effect of sex on the correlation and to create linear regression equation for age estimation in Thai population for forensic purposes. Blood samples obtained from unrelated healthy Thai fresh cadavers without anatomical organ abnormalities were used in this study. All cadaver subjects underwent the postmortem examination in jurisdiction of the Department of Forensic Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, and Institute of Forensic Medicine, Police General Hospital. Fifty blood samples from both sexes of all ages divided into 6 groups for equal age distribution (0-11, 12-23, 24-35, 36-47, 48-59, and 60 years old and older) were collected for a total of 100 samples. The extracted genomic DNA samples were then subjected to telomere length estimation by terminal restriction fragment (TRF) assay. The results showed that the mean TRF length was inversely correlated with age (r = -0.625), and sex did not have a statistically significant influence on the association between age and mean TRF length (P > 0.05). The obtained linear regression equation was y = 113.538 ± 9.604 - 0.012 × (R = 0.391; P < 0.001). However, the correlation was too low to be used for age estimation with high certainty and a possible reason for this in part would be the postmortem DNA degradation at some level, even using fresh cadaver blood, and other biological factors such as ethnicity and DNA sources. Roughly, those individuals who had a mean TRF length

  10. The Japanese quail: a model for studying reproductive aging of hypothalamic systems.

    PubMed

    Ottinger, Mary Ann; Abdelnabi, Mahmoud; Li, Qichang; Chen, Kehong; Thompson, Nicola; Harada, Nobuhiro; Viglietti-Panzica, Carla; Panzica, Gian Carlo

    2004-01-01

    During aging, the decline of neuroendocrine, endocrine, and behavioral components of reproduction ultimately leads to reproductive failure. These studies considered both neuroendocrine and behavioral aspects of reproductive aging in Japanese quail, using chronological age and reproductive status to separate animals into experimental groups. In Study I, age-related changes in the gonadotropin releasing hormone (GnRH-I) system were investigated and a sharp decrease was observed in GnRH-I concentration in the median eminence of aging animals of both sexes, whereas preoptic-lateral septal region GnRH-I concentrations declined only in aging males. Immunohistochemistry confirmed these findings since aging females retained, whereas males lost GnRH-I cells. Functional changes were assessed by in vitro incubation of parasaggittal hypothalamic slices collected from young and old inactive males and females. Results showed reduced baseline GnRH-I release and diminished response to norepinephrine (NE). Deteriorating fertility also correlated with decreased male sexual behavior and loss of aromatase immunoreactive (AROM-ir) neurons in the medial, but not lateral preoptic nucleus (POA). Sexual behavior and AROM-ir were restored with exogenous testosterone, which was associated with increased cell size in the medial POA. Comparison of cell size and number of AROM-ir cells showed that aged sexually active males had fewer, larger AROM-ir cells when compared to young males, suggesting neuroplasticity of specific neural systems and a critical role of estradiol in maintaining reproductive function.

  11. Is 27 really a dangerous age for famous musicians? Retrospective cohort study

    PubMed Central

    Wolkewitz, Martin; Allignol, Arthur; Graves, Nicholas

    2011-01-01

    Objective To test the “27 club” hypothesis that famous musicians are at an increased risk of death at age 27. Design Cohort study using survival analysis with age as a time dependent exposure. Comparison was primarily made within musicians, and secondarily relative to the general UK population. Setting The popular music scene from a UK perspective. Participants Musicians (solo artists and band members) who had a number one album in the UK between 1956 and 2007 (n=1046 musicians, with 71 deaths, 7%). Main outcome measures Risk of death by age of musician, accounting for time dependent study entry and the number of musicians at risk. Risk was estimated using a flexible spline which would allow a bump at age 27 to appear. Results We identified three deaths at age 27 amongst 522 musicians at risk, giving a rate of 0.57 deaths per 100 musician years. Similar death rates were observed at ages 25 (rate=0.56) and 32 (0.54). There was no peak in risk around age 27, but the risk of death for famous musicians throughout their 20s and 30s was two to three times higher than the general UK population. Conclusions The 27 club is unlikely to be a real phenomenon. Fame may increase the risk of death among musicians, but this risk is not limited to age 27. PMID:22187325

  12. Understanding inter-individual variability in purpose: Longitudinal findings from the VA Normative Aging Study.

    PubMed

    Hill, Patrick L; Turiano, Nicholas A; Spiro, Avron; Mroczek, Daniel K

    2015-09-01

    Research has demonstrated the importance of having a purpose in older adulthood; however, little is known about whether and how individuals vary on sense of purpose over time. The current study examined patterns of mean- and individual-level change in purpose among men in the Veterans Affairs Normative Aging Study (n = 587, M(age) = 74 years) across a 3-year span. Findings demonstrate that while little mean-level change was present, there was interindividual variability in change. Further research is needed to understand why these changes occur, as age, health status, and personality failed to predict individual fluctuations in purpose.

  13. 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

  14. Language of the aging brain: Event-related potential studies of comprehension in older adults

    PubMed Central

    Wlotko, Edward W.; Lee, Chia-Lin; Federmeier, Kara D.

    2010-01-01

    Normal aging brings increased richness in knowledge and experience as well as declines in cognitive abilities. Event-related brain potential (ERP) studies of language comprehension corroborate findings showing that the structure and organization of semantic knowledge remains relatively stable with age. Highlighting the advantages of the temporal and functional specificity of ERPs, this survey focuses on age-related changes in higher-level processes required for the successful comprehension of meaning representations built from multiple words. Older adults rely on different neural pathways and cognitive processes during normal, everyday comprehension, including a shift away from the predictive use of sentential context, differential recruitment of neural resources, and reduced engagement of controlled processing. Within age groups, however, there are important individual differences that, for example, differentiate a subset of older adults whose processing patterns more closely resemble that of young adults, providing a window into cognitive skills and abilities that may mediate or moderate age-related declines. PMID:20823949

  15. Sustained enjoyment of life and mortality at older ages: analysis of the English Longitudinal Study of Ageing

    PubMed Central

    Zaninotto, Paola; Wardle, Jane

    2016-01-01

    Objective To test whether the number of reports of enjoyment of life over a four year period is quantitatively associated with all cause mortality, and with death from cardiovascular disease and from other causes. Design and setting Longitudinal observational population study using the English Longitudinal Study of Ageing (ELSA), a nationally representative sample of older men and women living in England. Participants 9365 men and women aged 50 years or older (mean 63, standard deviation 9.3) at recruitment. Main outcome measures Time to death, based on mortality between the third phase of data collection (wave 3 in 2006) and March 2013 (up to seven years). Results Subjective wellbeing with measures of enjoyment of life were assessed in 2002 (wave 1), 2004 (wave 2), and 2006 (wave 3). 2264 (24%) respondents reported no enjoyment of life on any assessment, with 1833 (20%) reporting high enjoyment on one report of high enjoyment of life, 2063 (22%) on two reports, and 3205 (34%) on all three occasions. 1310 deaths were recorded during follow-up. Mortality was inversely associated with the number of occasions on which participants reported high enjoyment of life. Compared with the no high enjoyment group, the hazard ratio for all cause mortality was 0.83 (95% confidence interval 0.70 to 0.99) for two reports of enjoyment of life, and 0.76 (0.64 to 0.89) for three reports, after adjustment for demographic factors, baseline health, mobility impairment, and depressive symptoms. The same association was observed after deaths occurring within two years of the third enjoyment measure were excluded (0.90 (0.85 to 0.95) for every additional report of enjoyment), and in the complete case analysis (0.90 (0.83 to 0.96)). Conclusions This is an observational study, so causal conclusions cannot be drawn. Nonetheless, the results add a new dimension to understanding the significance of subjective wellbeing for health outcomes by documenting the importance of sustained

  16. Identity Formation in Adulthood: A Longitudinal Study from Age 27 to 50

    PubMed Central

    Fadjukoff, Päivi; Pulkkinen, Lea; Kokko, Katja

    2016-01-01

    ABSTRACT Longitudinal patterns of identity formation were analyzed in a representative cohort group of Finnish men and women born in 1959 across ages 27, 36, 42, and 50. The data were drawn from the Jyväskylä Longitudinal Study of Personality. Identity status (diffused, moratorium, foreclosed, achieved) from all four ages was available for 172 participants (54% females). Marcia’s Identity Status Interview used in this research included five domains: religious beliefs, political identity, occupational career, intimate relationships, and lifestyle. The findings indicated great variability in identity status across domains at each age level, and the identity trajectories fluctuated from age 27 to 50. The developmental trend from age 27 to 50 was moderately progressive (toward achievement) for the five domains and for overall identity, with the exception of a slightly regressive trend in male religious identity. Remaining stable in the same status category across the four measurements was rare and emerged only for diffusion in the ideological domains. Women generally outnumbered men in identity achievement at earlier ages, but the gender differences diminished in most domains at age 50, except in religious identity. In women overall diffusion decreased over time, but in men it remained at about 20% at ages 42 and 50. PMID:27019650

  17. Structural hippocampal network alterations during healthy aging: a multi-modal MRI study

    PubMed Central

    Pelletier, Amandine; Periot, Olivier; Dilharreguy, Bixente; Hiba, Bassem; Bordessoules, Martine; Pérès, Karine; Amieva, Hélène; Dartigues, Jean-François; Allard, Michèle; Catheline, Gwénaëlle

    2013-01-01

    While hippocampal atrophy has been described during healthy aging, few studies have examined its relationship with the integrity of White Matter (WM) connecting tracts of the limbic system. This investigation examined WM structural damage specifically related to hippocampal atrophy in healthy aging subjects (n = 129), using morphological MRI to assess hippocampal volume and Diffusion Tensor Imaging (DTI) to assess WM integrity. Subjects with Mild Cognitive Impairment (MCI) or dementia were excluded from the analysis. In our sample, increasing age was significantly associated with reduced hippocampal volume and reduced Fractional Anisotropy (FA) at the level of the fornix and the cingulum bundle. The findings also demonstrate that hippocampal atrophy was specifically associated with reduced FA of the fornix bundle, but it was not related to alteration of the cingulum bundle. Our results indicate that the relationship between hippocampal atrophy and fornix FA values is not due to an independent effect of age on both structures. A recursive regression procedure was applied to evaluate sequential relationships between the alterations of these two brain structures. When both hippocampal atrophy and fornix FA values were included in the same model to predict age, fornix FA values remained significant whereas hippocampal atrophy was no longer significantly associated with age. According to this latter finding, hippocampal atrophy in healthy aging could be mediated by a loss of fornix connections. Structural alterations of this part of the limbic system, which have been associated with neurodegeneration in Alzheimer's disease, result at least in part from the aging process. PMID:24367331

  18. Microstructural and Hardness Studies of Cu-10wt.%Sn Alloy Under Different Aging Conditions

    NASA Astrophysics Data System (ADS)

    Bashir, Farooq; Butt, Muhammad Zakria; Saleemi, Farhat

    2008-02-01

    Microstructure of Cu-10wt.%Sn alloy, prepared by powder metallurgy technique and sintered at 900 °C for 120 min in hydrogen atmosphere, was studied by optical microscopy and XRD technique as a function of aging time. Isothermal aging of the alloy specimens was performed at 250 °C for a period of 30, 60, 120, 300, and 1440 min after solution treatment at 500 °C for 60 min. Rockwell hardness of aged specimens was also measured at room temperature as a function of aging time. It was observed that microstructure of the as-sintered specimens consists of the grains of alpha Cu-Sn solid solution. Moreover, solution treatment of the alloy specimens followed by quenching in water increased the hardness of the as-sintered alloy specimens from 35.5 to 59.8 HRF due to the residual stresses generated by fast cooling. Aging at 250 °C for 30, 60, and 120 min was found to cause a decrease in hardness from 59.8 to 45.1 HRF, whereas the specimens aged for 300 and 1440 min show an increase in hardness from 45.1 to 75.7 HRF. The values of porosity calculated from XRD patterns of the alloy specimens referred to show that porosity varies with aging time in a manner opposite to that of hardness, e.g., porosity is maximum for 120 min aging time where hardness is minimum.

  19. Cohort Differences in Cognitive Aging and Terminal Decline in the Seattle Longitudinal Study

    PubMed Central

    Gerstorf, Denis; Ram, Nilam; Hoppmann, Christiane; Willis, Sherry L.; Schaie, K. Warner

    2011-01-01

    Life span researchers have long been interested in how and why fundamental aspects of human ontogeny differ between cohorts of people who have lived through different historical epochs. When examined at the same age, later born cohorts are often cognitively and physically fitter than earlier born cohorts. Less is known, however, about cohort differences in the rate of cognitive aging and if, at the very end of life, pervasive mortality-related processes overshadow and minimize cohort differences. We used data on 5 primary mental abilities from the Seattle Longitudinal Study (Schaie, 2005) to compare both age-related and mortality-related changes between earlier born cohorts (1886–1913) and later born cohorts (1914–1948). Our models covary for several individual and cohort differences in central indicators of life expectancy, education, health, and gender. Age-related growth models corroborate and extend earlier findings by documenting level differences at age 70 of up to 0.50 SD and less steep rates of cognitive aging on all abilities between 50 and 80 years of age favoring the later born cohort. In contrast, mortality-related models provide limited support for positive cohort differences. The later born cohort showed steeper mortality-related declines. We discuss possible reasons why often reported positive secular trends in age-related processes may not generalize to the vulnerable segment of the population that is close to death and suggest routes for further inquiry. PMID:21517155

  20. Identity Formation in Adulthood: A Longitudinal Study from Age 27 to 50.

    PubMed

    Fadjukoff, Päivi; Pulkkinen, Lea; Kokko, Katja

    2016-01-02

    Longitudinal patterns of identity formation were analyzed in a representative cohort group of Finnish men and women born in 1959 across ages 27, 36, 42, and 50. The data were drawn from the Jyväskylä Longitudinal Study of Personality. Identity status (diffused, moratorium, foreclosed, achieved) from all four ages was available for 172 participants (54% females). Marcia's Identity Status Interview used in this research included five domains: religious beliefs, political identity, occupational career, intimate relationships, and lifestyle. The findings indicated great variability in identity status across domains at each age level, and the identity trajectories fluctuated from age 27 to 50. The developmental trend from age 27 to 50 was moderately progressive (toward achievement) for the five domains and for overall identity, with the exception of a slightly regressive trend in male religious identity. Remaining stable in the same status category across the four measurements was rare and emerged only for diffusion in the ideological domains. Women generally outnumbered men in identity achievement at earlier ages, but the gender differences diminished in most domains at age 50, except in religious identity. In women overall diffusion decreased over time, but in men it remained at about 20% at ages 42 and 50.

  1. Sex-specific age associations of ankle proprioception test performance in older adults: results from the Baltimore Longitudinal Study of Aging

    PubMed Central

    Ko, Seung-Uk; Simonsick, Eleanor; Deshpande, Nandini; Ferrucci, Luigi

    2015-01-01

    Objectives: this study was aimed to test the hypothesis that ankle proprioception assessed by custom-designed proprioception testing equipment changes with ageing in men and women. Methods: ankle proprioception was assessed in 289 participants (131 women) of the Baltimore Longitudinal Study of Aging (BLSA); the participants aged 51–95 years and were blinded during testing. Results: the average minimum perceived ankle rotation was 1.11° (SE = 0.07) in women and 1.00° (SE = 0.06) in men, and it increased with ageing in both sexes (P < 0.001, for both). Ankle tracking performance, which is the ability to closely follow with the left ankle, a rotational movement induced on the right ankle by a torque motor, declines with ageing in both men and women (P = 0.018 and P = 0.011, respectively). Conclusions: a simple, standardised method for assessing ankle proprioception was introduced in this study using a customized test instrument, software and test protocol. Age-associated reduction in ankle proprioception was confirmed from two subtests of threshold and tracking separately for women and men. Findings in this study prompt future studies to determine whether these age-associated differences in the threshold for passive motion detection and movement tracking are evident in longitudinal study and how these specific deficits in ankle proprioception are related to age-associated chronic conditions such as knee or hip osteoarthritis and type II diabetes and affect daily activities such as gait. PMID:25637144

  2. Implications of Extending the ADHD Age-of-Onset Criterion to Age 12: Results from a Prospectively Studied Birth Cohort

    ERIC Educational Resources Information Center

    Polanczyk, Guilherme; Caspi, Avshalom; Houts, Renate; Kollins, Scott H.; Rohde, Luis Augusto; Moffitt, Terrie E.

    2010-01-01

    Objective: To evaluate whether including children with onset of symptoms between ages 7 and 12 years in the ADHD diagnostic category would: (a) increase the prevalence of the disorder at age 12, and (b) change the clinical and cognitive features, impairment profile, and risk factors for ADHD compared with findings in the literature based on the…

  3. Evidence for aging theories from the study of a hunter-gatherer people (Ache of Paraguay).

    PubMed

    Libertini, G

    2013-09-01

    In the late seventies, a small tribal population of Paraguay, the Ache, living under natural conditions, was studied. Data from this population turn out to be useful for considerations about evolutionary hypotheses on the aging phenomenon. 1) Ache show an age-related increasing mortality, which strongly limits the mean duration of life, as observed in other studies on mammal and bird species. 2) According to current theories on aging, in the wild very few or no individual reach old age and, so, aging cannot be directly influenced by natural selection. However, data from our population show that a significant proportion of the population reaches in the wild 60 and 70 years of age. 3) Data from Ache are also in agreement with the observation about an inverse correlation between extrinsic mortality and deaths due to the age-related increasing mortality. 4) For many gerontologists, the age-related decline of vital functions is a consequence of the gradual decline of cell turnover, genetically determined and regulated by the declining duplication capacities of stem cells. The current interpretation is that these restrictions are a general defense against the proliferation of any tumoral mass. However, among wild Ache cancer is virtually unknown in non-elderly subjects, and only among older individuals are there deaths attributable to oncological diseases. Moreover, fitness decline begins long before oncological diseases have fatal effects in significant numbers. This completely disproves the current hypothesis, because a supposed defense against a deadly disease cannot exterminate a population before the disease begins to kill. These data are consistent with similar data from other species studied under natural conditions, and they bring new arguments against the non-adaptive interpretation of aging and in support of the adaptive interpretation.

  4. The impact of male age on embryo quality: a retrospective study using time-lapse imaging

    PubMed Central

    Rosário, Guilherme R. F.; Vidal, Diana S.; Silva, Adriana V.; Franco, Antônio C. C.

    2016-01-01

    Objective This study aimed to correlate male age with embryo morphokinetic parameters on D3 considering the timing and the exact moment of embryo cleavage. Methods Time-lapse imaging was used to produce an ideal cleavage curve for the embryos analyzed. The percentage of embryos under the curve was analyzed and correlated with male age. Results 32.6% of the embryos from patients aged 28-33 years were under the curve; 36.2% of the embryos from patients aged 34-39 years were under the curve; 41.3% of the embryos from patients aged 40-45 years were under the curve; and 26.3% of the embryos fro patients aged 46-57 years were under the curve. Conclusions a statistically non-significant decrease was observed in the percentage of embryos under the optimal cleavage curve on D3 in the group of men aged between 40 and 45 years. Further studies looking into embryos in the blastocyst stage (D5 or D6) are required. PMID:28050955

  5. Need for recovery from work in relation to age: a prospective cohort study

    PubMed Central

    Jansen, N. W. H.; Kant, IJ.

    2009-01-01

    Purpose To investigate the impact of increasing age on the need for recovery (NFR) over time among day workers Methods The study is based on data from the first 2 years of follow-up of the Maastricht Cohort Study (n = 7,734). To investigate whether age predicted the onset of elevated NFR, multivariate survival analyses were conducted Results The highest levels of NFR were observed in the age group of 46–55 years. The relative risk for developing elevated NFR was highest in the age groups 36–45 years (RR 1.30; 1.07–1.58) and 46–55 years (RR 1.25; 1.03–1.52) in men and 46–55 years (RR 1.36; 1.04–1.77) in women when compared to the reference group Conclusions While NFR increased with age until the age of 55, this was followed by decreased levels of NFR among older employees. Explanations for the decreasing levels of NFR in the highest age group can be found in several domains such as the work environment, private situation and compensation strategies. PMID:19960222

  6. Magnetic ageing study of high and medium permeability nanocrystalline FeSiCuNbB alloys

    NASA Astrophysics Data System (ADS)

    Lekdim, Atef; Morel, Laurent; Raulet, Marie-Ange

    2017-04-01

    increasing the energy efficiency is one of the most important issues in modern power electronic systems. In aircraft applications, the energy efficiency must be associated with a maximum reduction of mass and volume, so a high components compactness. A consequence from this compactness is the increase of operating temperature. Thus, the magnetic materials used in these applications, have to work at high temperature. It raises the question of the thermal ageing problem. The reliability of these components operating at this condition becomes a real problem which deserves serious interest. Our work takes part in this context by studying the magnetic material thermal ageing. The nanocrystalline materials are getting more and more used in power electronic applications. Main advantages of nanocrystalline materials compared to ferrite are: high saturation flux density of almost 1.25 T and low dynamic losses for low and medium frequencies. The nanocrystalline Fe73.5Cu1Nb3Si15.5B7 alloys have been chosen in our aging study. This study is based on monitoring the magnetic characteristics for several continuous thermal ageing (100, 150, 200 and 240 °C). An important experimental work of magnetic characterization is being done following a specific monitoring protocol. Elsewhere, X-Ray Diffraction and magnetostriction measurements were carried out to support the study of the anisotropy energies evolution with ageing. This latter is discussed in this paper to explain and give hypothesis about the ageing phenomena.

  7. Compatibility and accelerated aging study for Li(Si)/FeS2 thermally activated batteries

    NASA Astrophysics Data System (ADS)

    Mead, J. W.; Searcy, J. Q.; Neiswander, P. A.; Poole, R. L.

    Thermally activated batteries using Li(Si)/FeS2 for use in systems which require a storage life of 25 years and high reliability are examined. All of the materials in the system, both organic and inorganic are incorporated except the heat paper and electric match are studied. No compatibility or aging problems are indicated. The following results are reported: oxygen vanishes from the overgas in containers that were accelerated aged; hydrogen increases sharply in the overgas initially but generally decreases as aging progresses. No unexpected or significant changes were observed in the volume resistivity, glass transition temperature, or shear modulus or organic materials.

  8. 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.

  9. Predictors and Sequelae of Fractures in the Elderly: The Canadian Study of Health and Aging (CSHA)

    ERIC Educational Resources Information Center

    Ostbye, Truls; Walton, Ruth E.; Steenhuis, Runa; Hodsman, Anthony B.

    2004-01-01

    The objective of this study was to describe the incidence, type, risk factors, and sequelae of fractures experienced by community-dwelling elderly Canadians. Data are from the Canadian Study of Health and Aging (CSHA), a longitudinal cohort study, collected in three waves: baseline (1991), wave 2 (1996), and wave 3 (2001). In CSHA-2 (1996),…

  10. Intermittent Aging Dynamics in a Metallic Glass Studied by X-ray Photon Correlation Spectroscopy

    NASA Astrophysics Data System (ADS)

    Evenson, Zach; Ruta, Beatrice; Hechler, Simon; Stolpe, Moritz; Pineda, Eloi; Gallino, Isabella; Busch, Ralf

    Although physical aging is a universal feature of glasses and other non-equilibrium matter, the atomic-level processes involved still remain a puzzling mystery. Here we study the microscopic aging dynamics of a metallic glass using coherent X-rays. Contrary to the common assumption of a steady slowing down of the dynamics usually observed in macroscopic studies, we show that the structural relaxation processes underlying aging in this metallic glass are intermittent and highly heterogeneous at the atomic scale. Moreover, physical aging is triggered by cooperative atomic rearrangements, driven by the relaxation of internal stresses. These results strengthen the similarities between metallic glasses and non-equilibrium soft materials and a suggest a common microscopic origin stemming from from a complex energy landscape.

  11. Gestational Age and Neonatal Brain Microstructure in Term Born Infants: A Birth Cohort Study

    PubMed Central

    Broekman, Birit F. P.; Wang, Changqing; Li, Yue; Rifkin-Graboi, Anne; Saw, Seang Mei; Chong, Yap-Seng; Kwek, Kenneth; Gluckman, Peter D.; Fortier, Marielle V.; Meaney, Michael J.; Qiu, Anqi

    2014-01-01

    Objective Understanding healthy brain development in utero is crucial in order to detect abnormal developmental trajectories due to developmental disorders. However, in most studies neuroimaging was done after a significant postnatal period, and in those studies that performed neuroimaging on fetuses, the quality of data has been affected due to complications of scanning during pregnancy. To understand healthy brain development between 37–41 weeks of gestational age, our study assessed the in utero growth of the brain in healthy term born babies with DTI scanning soon after birth. Methods A cohort of 93 infants recruited from maternity hospitals in Singapore underwent diffusion tensor imaging between 5 to 17 days after birth. We did a cross-sectional examination of white matter microstructure of the brain among healthy term infants as a function of gestational age via voxel-based analysis on fractional anisotropy. Results Greater gestational age at birth in term infants was associated with larger fractional anisotropy values in early developing brain regions, when corrected for age at scan. Specifically, it was associated with a cluster located at the corpus callosum (corrected p<0.001), as well as another cluster spanning areas of the anterior corona radiata, anterior limb of internal capsule, and external capsule (corrected p<0.001). Conclusions Our findings show variation in brain maturation associated with gestational age amongst ‘term’ infants, with increased brain maturation when born with a relatively higher gestational age in comparison to those infants born with a relatively younger gestational age. Future studies should explore if these differences in brain maturation between 37 and 41 weeks of gestational age will persist over time due to development outside the womb. PMID:25535959

  12. A Cross-Sectional Study of Ageing and Cardiovascular Function over the Baboon Lifespan

    PubMed Central

    Yeung, Kristen R.; Pears, Suzanne; Heffernan, Scott J.; Makris, Angela; Hennessy, Annemarie; Lind, Joanne M.

    2016-01-01

    Background Ageing is associated with changes at the molecular and cellular level that can alter cardiovascular function and ultimately lead to disease. The baboon is an ideal model for studying ageing due to the similarities in genetic, anatomical, physiological and biochemical characteristics with humans. The aim of this cross-sectional study was to investigate the changes in cardiovascular profile of baboons over the course of their lifespan. Methods Data were collected from 109 healthy baboons (Papio hamadryas) at the Australian National Baboon Colony. A linear regression model, adjusting for sex, was used to analyse the association between age and markers of ageing with P < 0.01 considered significant. Results Male (n = 49, 1.5–28.5 years) and female (n = 60, 1.8–24.6 years) baboons were included in the study. Age was significantly correlated with systolic (R2 = 0.23, P < 0.001) and diastolic blood pressure (R2 = 0.44, P < 0.001), with blood pressure increasing with age. Age was also highly correlated with core augmentation index (R2 = 0.17, P < 0.001) and core pulse pressure (R2 = 0.30, P < 0.001). Creatinine and urea were significantly higher in older animals compared to young animals (P < 0.001 for both). Older animals (>12 years) had significantly shorter telomeres when compared to younger (<3 years) baboons (P = 0.001). Conclusion This study is the first to demonstrate that cardiovascular function alters with age in the baboon. This research identifies similarities within cardiovascular parameters between humans and baboon even though the length of life differs between the two species. PMID:27427971

  13. Vulnerability to unhealthy behaviours across different age groups in Swedish Adolescents: a cross-sectional study

    PubMed Central

    Paulsson Do, Ulrica; Edlund, Birgitta; Stenhammar, Christina; Westerling, Ragnar

    2014-01-01

    Purpose: There is lack of evidence on the effects of health-promoting programmes among adolescents. Health behaviour models and studies seldom compare the underlying factors of unhealthy behaviours between different adolescent age groups. The main objective of this study was to investigate factors including sociodemographic parameters that were associated with vulnerability to health-damaging behaviours and non-adoption of health-enhancing behaviours in different adolescent age groups. Methods: A survey was conducted among 10,590 pupils in the age groups of 13–14, 15–16 and 17–18 years. Structural equation modelling was performed to determine whether health-damaging behaviours (smoking and alcohol consumption) and non-adoption of health-enhancing behaviours (regular meal habits and physical activity) shared an underlying vulnerability. This method was also used to determine whether gender and socio-economic status were associated with an underlying vulnerability to unhealthy behaviours. Results: The findings gave rise to three models, which may reflect the underlying vulnerability to health-damaging behaviours and non-adoption of health-enhancing behaviours at different ages during adolescence. The four behaviours shared what was interpreted as an underlying vulnerability in the 15–16-year-old age group. In the youngest group, all behaviours except for non-participation in physical activity shared an underlying vulnerability. Similarly, alcohol consumption did not form part of the underlying vulnerability in the oldest group. Lower socio-economic status was associated with an underlying vulnerability in all the age groups; female gender was associated with vulnerability in the youngest adolescents and male gender among the oldest adolescents. Conclusions: These results suggest that intervention studies should investigate the benefits of health-promoting programmes designed to prevent health-damaging behaviours and promote health-enhancing behaviours in

  14. A Narrative Study of the Experiences that Impact Educational Choices of Middle-Aged Women

    ERIC Educational Resources Information Center

    Perez, Shireese Redmond

    2011-01-01

    The purpose of this qualitative study was to answer the research questions of how middle-aged women perceive higher education and why they do or do not pursue a higher level of education. According to the U.S. Census Bureau's 2009 American Community Survey microdata, more than half of the women between the ages of 30-50 years in one Midwestern US…

  15. Parental age and lifespan influence offspring recruitment: a long-term study in a seabird.

    PubMed

    Torres, Roxana; Drummond, Hugh; Velando, Alberto

    2011-01-01

    Recent studies of wild populations provide compelling evidence that survival and reproduction decrease with age because of senescence, a decline in functional capacities at old ages. However, in the wild, little is known about effects of parental senescence on offspring quality. We used data from a 21-year study to examine the role of parental age on offspring probability of recruitment in a long-lived bird, the blue-footed booby (Sula nebouxii). Offspring probability of recruiting into the breeding population varied over the life of parents and effects age were similar in mothers and fathers. Offspring recruitment was high when parents were roughly 6-12 years old and low before and after then. Effects of parental age on offspring recruitment varied with lifespan (parental age at last reproduction) and previous breeding experience. Offspring recruitment from young and old parents with long reproductive lifespans was greater than that of offspring from parents with short lifespans at young and old ages. For parents with little previous breeding experience recruitment of offspring decreased with their hatch date, but experienced parents were no similarly affected. We found evidence of terminal effects on offspring recruitment in young parents but not in older parents, suggesting that senescence is more likely a gradual process of deterioration than a process of terminal illness. Failure to recruit probably reflects mortality during the first years after independence but also during the fledgling transition to full independence. Our results show effects of parental age and quality on offspring viability in a long-lived wild vertebrate and support the idea that wild populations are composed of individuals of different quality, and that this individual heterogeneity can influence the dynamics of age-structured populations.

  16. Age Related Incidence and Early Outcomes of Hip Fractures: A Prospective Cohort Study of 1177 patients

    PubMed Central

    2011-01-01

    Introduction Associated with the increase in the aging population, there is an increase in the incidence of hip fractures worldwide. Outcome following such fractures is affected by age of the patient. This study aims to assess the incidence and early outcome of hip fractures, comparing between different age groups. Methods Data of hip fractures collected over a period of five years was analysed. Patients were divided into three groups, group A (patients under the age of 64), group B (patients between 65 and 84 years of age), and group C (patients over the age of 85). Results Of the 1177 patients included in the study, there were 90 patients in group A, 702 patients in group B and 385 patients in group C. There was a female preponderance across all age groups, and this increased as age advanced (p < 0.0001). A significantly larger number of older patients lived alone and needed aids to walk before the injury (p < 0.0001). There was no significant difference in the type of fracture across the three groups (p = 0.13). A higher proportion of the elderly with intracapsular fractures were treated by replacement arthroplasty. Older patients who had internal fixation of intracapsular fractures had a better walking ability at 4 months. The overall deterioration in mobility was greater in older patients (p < 0.0001). Mortality was higher in older patients. Conclusions Hip fractures are more common among females irrespective of age group. Older patients have a higher mortality and a greater deterioration of walking ability after such injuries. Internal fixation of intracapsular fractures have demonstrated satisfactory early outcome in the immediate period. This could be attributed to retention of native bone, better propioception and shorter operation time. PMID:21261942

  17. Association of maternal age with child health: A Japanese longitudinal study

    PubMed Central

    2017-01-01

    Average maternal age at birth has been rising steadily in Western and some Asian countries. Older maternal age has been associated with adverse pregnancy and birth outcomes; however, studies on the relationship between maternal age and young children’s health remain scarce. Therefore, we sought to investigate the association of maternal age with child health outcomes in the Japanese population. We analyzed data from two birth cohorts of the nationwide Japanese Longitudinal Survey of Babies in 21st Century (n2001 = 47,715 and n2010 = 38,554). We estimated risks of unintentional injuries and hospital admissions at 18 and 66 months according to maternal age, controlling for the following potential confounders: parental education; maternal parity, smoking status, and employment status; household income; paternal age, and sex of the child. We also included the following as potential mediators: preterm births and birthweight. We observed a decreasing trend in the risks of children’s unintentional injuries and hospital admissions at 18 months according to maternal age in both cohorts. In the 2001 cohort, compared to mothers <25 years, odds ratios of hospital admission at 18 months were 0.97 [95% CI: 0.86, 1.09], 0.92 [0.81, 1.05], 0.76 [0.65, 0.90], and 0.71 [0.51, 0.98] for mothers aged 25.0–29.9, 30.0–34.9, 35.0–39.9, and >40.0 years, respectively, controlling for confounders. Our findings were in line with previous findings from population-based studies conducted in the United Kingdom and Canada suggesting that older maternal age may be beneficial for early child health. PMID:28234951

  18. Parental Age and Lifespan Influence Offspring Recruitment: A Long-Term Study in a Seabird

    PubMed Central

    Torres, Roxana; Drummond, Hugh; Velando, Alberto

    2011-01-01

    Recent studies of wild populations provide compelling evidence that survival and reproduction decrease with age because of senescence, a decline in functional capacities at old ages. However, in the wild, little is known about effects of parental senescence on offspring quality. We used data from a 21-year study to examine the role of parental age on offspring probability of recruitment in a long-lived bird, the blue-footed booby (Sula nebouxii). Offspring probability of recruiting into the breeding population varied over the life of parents and effects age were similar in mothers and fathers. Offspring recruitment was high when parents were roughly 6–12 years old and low before and after then. Effects of parental age on offspring recruitment varied with lifespan (parental age at last reproduction) and previous breeding experience. Offspring recruitment from young and old parents with long reproductive lifespans was greater than that of offspring from parents with short lifespans at young and old ages. For parents with little previous breeding experience recruitment of offspring decreased with their hatch date, but experienced parents were no similarly affected. We found evidence of terminal effects on offspring recruitment in young parents but not in older parents, suggesting that senescence is more likely a gradual process of deterioration than a process of terminal illness. Failure to recruit probably reflects mortality during the first years after independence but also during the fledgling transition to full independence. Our results show effects of parental age and quality on offspring viability in a long-lived wild vertebrate and support the idea that wild populations are composed of individuals of different quality, and that this individual heterogeneity can influence the dynamics of age-structured populations. PMID:22087271

  19. Looking age-appropriate while growing old gracefully: A qualitative study of ageing and body image among older adults.

    PubMed

    Jankowski, Glen S; Diedrichs, Phillippa C; Williamson, Heidi; Christopher, Gary; Harcourt, Diana

    2016-04-01

    Body dissatisfaction can be significantly detrimental to wellbeing. Little is known about older adults' body image, despite the fact that ageing causes unique bodily changes and that sociocultural pressures to resist these changes abound. We conducted six focus groups with a UK community sample of White British and South Asian older adults aged 65-92 years. Thematic analysis highlighted four themes: appearance indicates capability and identity; physical ability trumps appearance; felt pressures to age 'gracefully' while resisting appearance changes; and gender and cultural differences. These findings suggest that older adults' body image can have important implications for their wellbeing and merits researchers' attention.

  20. Does eating particular diets alter risk of age-related macular degeneration in users of the Age-Related Eye Disease Study supplements?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Recent information suggests that the Age-Related Eye Disease Study (AREDS) supplement, enhanced intake of omega-3 fatty acids, and diminishing dietary glycemic index (dGI) are protective against advanced age-related macular degeneration (AMD). Methods: Dietary information was collected a...

  1. Aging and the Aged in the Third World: Part II. Regional and Ethnographic Perspectives. Studies in Third World Societies, Publication Number Twenty-Three.

    ERIC Educational Resources Information Center

    Sokolovsky, Jay; Sokolovsky, Joan

    A volume devoted to aging and the aged in Third World societies focuses on ethnographic case studies from Papua New Guinea, China, India, the Sudan, and Mexico. The first of five articles, "Sweeping Men and Harmless Women: Responsibility and Gender Identity in Later Life" (Dorothy Ayers Counts), examines the perception of gender over the…

  2. 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

  3. Age difference in numeral recognition and calculation: an event-related potential study.

    PubMed

    Xuan, Dong; Wang, Suhong; Yang, Yilin; Meng, Ping; Xu, Feng; Yang, Wen; Sheng, Wei; Yang, Yuxia

    2007-01-01

    In this study, we investigated the age difference in numeral recognition and calculation in one group of school-aged children (n = 38) and one of undergraduate students (n = 26) using the event-related potential (ERP) methods. Consistent with previous reports, the age difference was significant in behavioral results. Both numeral recognition and calculation elicited a negativity peaking at about 170-280 ms (N2) and a positivity peaking at 200-470 ms (pSW) in raw ERPs, and a difference potential (dN3) between 360 and 450 ms. The difference between the two age groups indicated that more attention resources were devoted to arithmetical tasks in school-aged children, and that school-aged children and undergraduate students appear to use different strategies to solve arithmetical problems. The analysis of frontal negativity suggested that numeral recognition and mental calculation impose greater load on working memory and executive function in schoolchildren than in undergraduate students. The topography data determined that the parietal regions were responsible for arithmetical function in humans, and there was an age-related difference in the area of cerebral activation.

  4. 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.

  5. 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.

  6. Does baseline innate immunity change with age? A multi-year study in great tits.

    PubMed

    Vermeulen, Anke; Eens, Marcel; Van Dongen, Stefan; Müller, Wendt

    2017-03-16

    Throughout their life animals progressively accumulate mostly detrimental changes in cells, tissues and their functions, causing a decrease in individual performance and ultimately an increased risk of death. The latter may be amplified if it also leads to a deterioration of the immune system which forms the most important protection against the permanent threat of pathogens and infectious diseases. Here, we investigated how four baseline innate immune parameters (natural antibodies, complement activity, concentrations of haptoglobin and concentrations of nitric oxide) changed with age in free-living great tits (Parus major). We applied both cross-sectional and longitudinal approaches as birds were sampled for up to three years of their lives. Three out of the four selected innate immune parameters were affected by age. However, the shape of the response curves differed strongly among the innate immune parameters. Natural antibody levels increased during early life until mid-age to decrease thereafter when birds aged. Complement activity was highest in young birds, while levels slightly decreased with increasing age. Haptoglobin levels on the other hand, showed a linear, but highly variable increase with age, while nitric oxide concentrations were unaffected by age. The observed differences among the four studied innate immune traits not only indicate the importance of considering several immune traits at the same time, but also highlight the complexity of innate immunity. Unraveling the functional significance of the observed changes in innate immunity is thus a challenging next step.

  7. Physical ageing of polyethylene terephthalate under natural sunlight: correlation study between crystallinity and mechanical properties

    NASA Astrophysics Data System (ADS)

    Aljoumaa, Khaled; Abboudi, Maher

    2016-01-01

    Semi-crystalline polyethylene terephthalate (PET) was aged under the effect of natural UV exposure and outdoor temperature during 670 days. The variation in the mechanical and thermal properties beside to the morphology was tracked by applying different analytical techniques, including scanning electron microscopy, infrared spectroscopy, differential scanning calorimetry and wide angle X-ray diffraction, in addition to tensile strength and hardness measurements. It has been confirmed that the ageing process is the results of physical trend only. The aged PET showed a decrease in both tensile strength and strain with an increase in the degree of crystallinity of aged PET samples during the whole period. These changes in crystallinity were examined by various analysis methods: density, calorimetric and infrared spectroscopy. New peaks in FTIR analysis at 1115 and 1090 cm-1 were characterized and proved that this technique is considered to be an easy tool to track the change in the surface crystallinity of aged PET samples directly. The results of this study showed that an augmentation in the degree of crystallinity of outdoor aged PET samples from 18 to 36 %, accompanied with a decrease in tensile strength from 167.9 to 133.7 MPa. Moreover, a good exponential correlation was found between the degree of crystallinity and the mechanical properties of the aged PET.

  8. Pathways to Adult Marijuana and Cocaine Use: A Prospective Study of African Americans from Age 6 to 42

    ERIC Educational Resources Information Center

    Fothergill, Kate E.; Ensminger, Margaret E.; Green, Kerry M.; Robertson, Judith A.; Juon, Hee Soon

    2009-01-01

    This study examines pathways to adult marijuana and cocaine use in a cohort of African Americans from Woodlawn, an inner city community in Chicago. Assessments were conducted in first grade (age 6), adolescence (age 16), early adulthood (age 32), and in mid-adulthood (age 42). The "social adaptation life course" framework guided the…

  9. Aging affects the interaction between attentional control and source memory: an fMRI study.

    PubMed

    Dulas, Michael R; Duarte, Audrey

    2014-12-01

    Age-related source memory impairments may be due, at least in part, to deficits in executive processes mediated by the PFC at both study and test. Behavioral work suggests that providing environmental support at encoding, such as directing attention toward item-source associations, may improve source memory and reduce age-related deficits in the recruitment of these executive processes. The present fMRI study investigated the effects of directed attention and aging on source memory encoding and retrieval. At study, participants were shown pictures of objects. They were either asked to attend to the objects and their color (source) or to their size. At test, participants determined if objects were seen before, and if so, whether they were the same color as previously. Behavioral results showed that direction of attention improved source memory for both groups; however, age-related deficits persisted. fMRI results revealed that, across groups, direction of attention facilitated medial temporal lobe-mediated contextual binding processes during study and attenuated right PFC postretrieval monitoring effects at test. However, persistent age-related source memory deficits may be related to increased recruitment of medial anterior PFC during encoding, indicative of self-referential processing, as well as underrecruitment of lateral anterior PFC-mediated relational processes. Taken together, this study suggests that, even when supported, older adults may fail to selectively encode goal-relevant contextual details supporting source memory performance.

  10. Brain tissue volumes in the general population of the elderly: the AGES-Reykjavik study.

    PubMed

    Sigurdsson, Sigurdur; Aspelund, Thor; Forsberg, Lars; Fredriksson, Jesper; Kjartansson, Olafur; Oskarsdottir, Bryndis; Jonsson, Palmi V; Eiriksdottir, Gudny; Harris, Tamara B; Zijdenbos, Alex; van Buchem, Mark A; Launer, Lenore J; Gudnason, Vilmundur

    2012-02-15

    Imaging studies have reported conflicting findings on how brain structure differs with age and sex. This may be explained by discrepancies and limitations in study population and study design. We report a study on brain tissue volumes in one of the largest cohorts of individuals studied to date of subjects with high mean age (mean ± standard deviation (SD) 76 ± 6 years). These analyses are based on magnetic resonance imaging (MRI) scans acquired at baseline on 4303 non-demented elderly, and 367 who had a second MRI, on average 2.5 ± 0.2 years later. Tissue segmentation was performed with an automatic image analysis pipeline. Total brain parenchymal (TBP) volume decreased with increasing age while there was an increase in white matter hyperintensities (WMH) in both sexes. A reduction in both normal white matter (NWM)- and gray matter (GM) volume contributed to the brain shrinkage. After adjusting for intra-cranial volume, women had larger brain volumes compared to men (3.32%, p < 0.001) for TBP volume in the cross-sectional analysis. The longitudinal analysis showed a significant age-sex interaction in TBP volume with a greater rate of annual change in men (-0.70%, 95%CI: -0.78% to -0.63%) than women (-0.55%, 95%CI: -0.61% to -0.49%). The annual change in the cross-sectional data was approximately 40% less than the annual change in the longitudinal data and did not show significant age-sex interaction. The findings indicate that the cross-sectional data underestimate the rate of change in tissue volumes with age as the longitudinal data show greater rate of change in tissue volumes with age for all tissues.

  11. "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.

  12. Age at Menarche and Cardiovascular Disease Mortality in Singaporean Chinese Women: The Singapore Chinese Health Study

    PubMed Central

    Mueller, NT; Odegaard, AO; Gross, MD; Koh, WP; Yuan, JM; Pereira, MA

    2012-01-01

    Purpose To examine whether menarcheal age was inversely associated with CVD mortality in Singaporean Chinese women. Methods 34,022 Chinese women aged 45–74 at enrollment (1993–1998), with complete data on study variables, were followed prospectively through 2009 for primary cause of death due to CVD, including coronary heart disease (CHD) and cerebrovascular disease (CERE). Hazard ratios (HRs) for CVD mortality were computed across menarcheal age categories and adjusted for potential confounders and BMI. Results Over 460,374 person-years of follow-up, 1,852 women died from CVD; 998 of them from CHD and 557 from CERE. There was a significant interaction between menarcheal age and smoking (p<0.05). In nonsmokers, menarcheal age was inversely associated with risk for CVD and CHD mortality. HRs (and 95% CI) for CVD mortality across menarcheal age categories (≤12, 13–14, 15–16, ≥17) were: 1.06 (0.87–1.29), 1 (referent), 0.89 (0.79–1.00), and 0.80 (0.69–0.93), respectively (ptrend<0.001); HRs for CHD mortality were: 1.06 (0.80–1.34), 1 (referent), 0.76 (0.65–0.90), and 0.72 (0.58–0.88), respectively (ptrend<0.001). In nonsmokers there was no association between menarcheal age and CERE mortality. Among smokers, menarcheal age was not associated with CVD, CHD or CERE mortality. Conclusion Menarcheal age was inversely associated with risk of CVD mortality in nonsmoking Chinese women. PMID:22939833

  13. Episodic memory in normal aging and Alzheimer disease: Insights from imaging and behavioral studies.

    PubMed

    Tromp, D; Dufour, A; Lithfous, S; Pebayle, T; Després, O

    2015-11-01

    Age-related cognitive changes often include difficulties in retrieving memories, particularly those that rely on personal experiences within their temporal and spatial contexts (i.e., episodic memories). This decline may vary depending on the studied phase (i.e., encoding, storage or retrieval), according to inter-individual differences, and whether we are talking about normal or pathological (e.g., Alzheimer disease; AD) aging. Such cognitive changes are associated with different structural and functional alterations in the human neural network that underpins episodic memory. The prefrontal cortex is the first structure to be affected by age, followed by the medial temporal lobe (MTL), the parietal cortex and the cerebellum. In AD, however, the modifications occur mainly in the MTL (hippocampus and adjacent structures) before spreading to the neocortex. In this review, we will present results that attempt to characterize normal and pathological cognitive aging at multiple levels by integrating structural, behavioral, inter-individual and neuroimaging measures of episodic memory.

  14. Age of the moon: An isotopic study of uranium-thorium-lead systematics of lunar samples

    USGS Publications Warehouse

    Tatsumoto, M.; Rosholt, J.N.

    1970-01-01

    Concentrations of U, Th, and Pb in Apollo 11 samples studied are low (U. 0.16 to 0.87; Th, 0.53 to 3.4; Pb, 0.29 to 1.7, in ppm) but the extremely radiogenic lead in samples allows radiometric dating. The fine dust and the breccia have a concordant age of 4.66 billion years on the basis of 207Pb/206Pb, 206Pb/238U, 207Pb/235U, and 208Pb/232Th ratios. This age is comparable with the age of meteorites and with the age generally accepted for the earth. Six crystalline and vesicular samples are distinctly younger than the dust and breccia. The 238U/235U ratio is the same as that in earth rocks, and 234U is in radioactive equilibrium with parent 238U.

  15. Age of the moon: an isotopic study of uranium-thorium-lead systematics of lunar samples.

    PubMed

    Tatsumoto, M; Rosholt, J N

    1970-01-30

    Concentrations of U, Th, and Pb in Apollo 11 samples studied are low (U. 0.16 to 0.87; Th, 0.53 to 3.4; Pb, 0.29 to 1.7, in ppm) but the extremely radiogenic lead in samples allows radiometric dating. The fine dust and the breccia have a concordant age of 4.66 billion years on the basis of (207)Pb/(206)Pb, (206)Pb/(238)U, (207)Pb/(235U), and(208)Pb/(232)Th ratios. This age is comparable with the age of meteorites and with the age generally accepted for the earth. Six crystalline and vesicular samples are distinctly younger than the dust and breccia. The (238)U/(235)U ratio is the same as that in earth rocks, and (234)U is in radioactive equilibrium with parent (238)U.

  16. 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.

  17. Study of the formation mechanisms of some volatile compounds during the aging of sweet fortified wines.

    PubMed

    Cutzach, I; Chatonnet, P; Dubourdieu, D

    1999-07-01

    Sweet fortified wines, traditionally aged under strong oxidation conditions, have a characteristic aroma. An experimental laboratory study investigated the aging of red and white sweet fortified wines under various conditions. The formation of various molecules, previously identified as characteristic of the aroma of this type of wine, was monitored by analysis. The development of these compounds during accelerated aging was affected by oxidation and the color of the wine. Among the molecules studied, sotolon [3-hydroxy-4, 5-dimethyl-2(5H)-furanone] was one of the few molecules present in concentrations above the perception threshold, in both red and white wines. Buildup was strongly affected by the presence of oxygen in white wine subjected to accelerated aging. (Ethoxymethyl)furfural, formed from 5-(hydroxymethyl)furfural, and furfural, derived from sugars, are also involved in the aroma of sweet fortified white wines aged in oxygen-free conditions. The substances most characteristic of accelerated aging of sweet fortified red wines were 5-(hydroxymethyl)furfural, acetylformoin, and hydroxymaltol, the formation of which is affected by oxidation, and dihydromaltol, formed in the absence of oxidation.

  18. Age-related changes in cognitive conflict processing: an event-related potential study.

    PubMed

    Mager, Ralph; Bullinger, Alex H; Brand, Serge; Schmidlin, Maria; Schärli, Heinz; Müller-Spahn, Franz; Störmer, Robert; Falkenstein, Michael

    2007-12-01

    Cognitive tasks involving conflicting stimuli and responses are associated with an early age-related decline in performance. Conflict and conflict-induced interference can be stimulus- or response-related. In classical stimulus-response compatibility tasks, such as the Stroop task, the event-related potential (ERP) usually reveals a greater negativity on incongruent versus congruent trials which has often been linked with conflict processing. However, it is unclear whether this negativity is related to stimulus- or response-related conflict, thus rendering the meaning of age-related changes inconclusive. In the present study, a modified Stroop task was used to focus on stimulus-related interference processes while excluding response-related interference. Since we intended to study work-relevant effects ERPs and performance were determined in young (about 30 years old) and middle-aged (about 50 years old) healthy subjects (total n=80). In the ERP, a broad negativity developed after incongruent versus congruent stimuli between 350 and 650 ms. An age-related increase of the latency and amplitude of this negativity was observed. These results indicate age-related alterations in the processing of conflicting stimuli already in middle age.

  19. 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.

  20. The Effect of Age on Fracture Risk: A Population-Based Cohort Study

    PubMed Central

    Chikritzhs, Tanya

    2016-01-01

    Aim. To precisely estimate the effect of age on the risk of fracture hospitalisation among the Western Australia population over the life course. Methods. This population-based cohort study used hospital data on fractures for the period January 1991 to January 2013 among Western Australians born between 1915 and 1990. Results. The average incidence rates (per 10,000 person-years) of fracture hospitalisation (95% confidence interval) were 50.12 (49.90, 50.35), 55.14 (54.82, 55.48), and 45.02 (44.71, 45.32) for both males and females, males only, and females only, respectively. The age-specific rate of fracture hospitalisation (in natural logarithm form) in adults (>18 years) was well predicted by age at its 1st, 2nd, and 3rd power in males with an adjusted R-squared of 0.98 and p < 0.001. For females, the trend was also well predicted by its 1st and 2nd powers (the 3rd power term of age was removed due to its p value > 0.8) with an adjusted R-squared of 0.99 and p < 0.001. Conclusions. Overall trends in age and gender specific risk of fracture among the Western Australian population were similar to estimates reported from previous studies. The trend in fracture hospitalisation risk over the life course can be almost fully explained by age. PMID:27340566

  1. UAS Integration in the NAS Project - FY 14 Annual Review

    NASA Technical Reports Server (NTRS)

    Grindle, Laurie; Randall, Debra; Hackenberg, Davis

    2014-01-01

    This briefing gives insight into the research activities and efforts being executed in order to integrate unmanned aircraft systems into the national airspace system. This briefing is to inform others of the UAS-NAS Projects progress and future directions.

  2. UAS Integration in the NAS FY15 Annual Review

    NASA Technical Reports Server (NTRS)

    Grindle, Laurie; Randall, Debra; Hackenburg, Davis

    2015-01-01

    This presentation gives insight into the research activities and efforts being executed in order to integrate unmanned aircraft systems into the national airspace system. This briefing is to inform others of the UAS-NAS progress and future directions.

  3. Learn with the Classics: Using Music To Study Smart at Any Age.

    ERIC Educational Resources Information Center

    Andersen, Ole; Marsh, Marcy; Harvey, Arthur

    This book, accompanied by a musical CD-ROM, provides information on how to enhance learning through music at any age. Sections include: (1) "Let Music Prime Your Brain For Learning," which teaches how important it is to prime the brain for learning through music; (2) "Study Smart," which demonstrates highly effective studying techniques devised by…

  4. A Cross-Age Study of an Understanding of Light and Sight Concepts in Physics

    ERIC Educational Resources Information Center

    Uzun, Salih; Alev, Nedim; Karal, Isik Saliha

    2013-01-01

    The aim of this study is to reveal the students' and pre-service teachers' understanding of light, sight and related concepts at different educational levels, from primary to higher education. A cross-sectional approach was used since the participants were of different age and educational level. The sample of this study consisted of 30 eighth…

  5. The Perceived Impact of Playing Music while Studying: Age and Cultural Differences

    ERIC Educational Resources Information Center

    Kotsopoulou, Anastasia; Hallam, Susan

    2010-01-01

    Rating scale questionnaires were administered to 600 students in three age groups, 12-13, 15-16 and 20-21 from Japan, the UK, Greece and the USA. The questionnaires explored the extent of playing music while studying, the kinds of tasks when music was played, the perceived effects of music on studying, the characteristics and types of music played…

  6. A feasibility study of wearable activity monitors for pre-adolescent school-age children

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding physical activity is the key to fighting childhood obesity. The objective of this study was to examine the feasibility of using certian wearable devices to measure physical activity among children. A qualitative study was conducted with 25 children aged 7 to 10 yearsto assess acceptabi...

  7. A feasibility study of wearable activity monitors for pre-adolescent school-aged children

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding physical activity is key in the fight against childhood obesity. The objective of this study was to examine the feasibility of using certain wearable devices to measure physical activity among children. A qualitative study was conducted with 25 children aged 7 to 10 years to assess ac...

  8. Osteoporosis Knowledge and Attitudes: A Cross-Sectional Study among College-Age Students

    ERIC Educational Resources Information Center

    Ford, M. Allison; Bass, Martha A.; Keathley, Roseanne

    2007-01-01

    Objective: The authors' purpose in this study was to investigate the influence of knowledge of osteoporosis, attitudes regarding osteoporosis, and knowledge of dietary calcium on dairy product intake in both male and female college-age students. Participants: The authors conducted this cross-sectional study on 911 men and women enrolled in 2…

  9. Ten Years Later: A Follow-Up Study of Professors Still Working after Age 70

    ERIC Educational Resources Information Center

    Dorfman, Lorraine T.

    2009-01-01

    Little is known about the impact of the end of mandatory retirement on professors over the long term. This follow-up study investigated the ten-year experience of professors who chose not to retire from a major research university after the elimination of the age 70 mandatory retirement in 1994. The initial interview study was conducted in 1998…

  10. The Gifted Rating Scales-School Form: A Validation Study Based on Age, Gender, and Race

    ERIC Educational Resources Information Center

    Pfeiffer, Steven; Petscher, Yaacov; Kumtepe, Alper

    2008-01-01

    This study examined the internal consistency and validity of a new rating scale to identify gifted students, the Gifted Rating Scales-School Form (GRS-S). The study explored the effect of gender, race/ethnicity, age, and rater familiarity on GRS-S ratings. One hundred twenty-two students in first to eighth grade from elementary and middle schools…

  11. Preschool Age Children, Divorce and Adjustment: A Case Study in Greek Kindergarten

    ERIC Educational Resources Information Center

    Babalis, Thomas; Xanthakou, Yiota; Papa, Christina; Tsolou, Olympia

    2011-01-01

    Introduction: The aim of this research, which was carried out in 2010, is the comparative study of the psychosocial adjustment of preschool children from divorced and nuclear families in the nursery school. Method: The sample of the study consisted of 60 students (mean age = 5.21), 30 preschool children of divorced parents and 30 preschool…

  12. Ages of Speech Sound Acquisition: Comparisons and Critiques of Several Normative Studies.

    ERIC Educational Resources Information Center

    Smit, Ann B.

    1986-01-01

    Studies of normative ages of speech sound acquisition vary in speech sample and methods used. Review of studies which sample spontaneous speech indicates that these data have characteristics that make them difficult to use as norms. Desirable characteristics of normative investigations of speech and sound acquisition are proposed. (Author/CL)

  13. Uranium-series comminution ages of continental sediments: Case study of a Pleistocene alluvial fan

    SciTech Connect

    Lee, Victoria E.; DePaolo, Donald J.; Christensen, John N.

    2010-04-30

    Obtaining quantitative information about the timescales associated with sediment transport, storage, and deposition in continental settings is important but challenging. The uranium-series comminution age method potentially provides a universal approach for direct dating of Quaternary detrital sediments, and can also provide estimates of the sediment transport and storage timescales. (The word"comminution" means"to reduce to powder," reflecting the start of the comminution age clock as reduction of lithic parent material below a critical grain size threshold of ~;;50 mu m.) To test the comminution age method as a means to date continental sediments, we applied the method to drill-core samples of the glacially-derived Kings River Fan alluvial deposits in central California. Sediments from the 45 m core have independently-estimated depositional ages of up to ~;;800 ka, based on paleomagnetism and correlations to nearby dated sediments. We characterized sequentially-leached core samples (both bulk sediment and grain size separates) for U, Nd, and Sr isotopes, grain size, surface texture, and mineralogy. In accordance with the comminution age model, where 234U is partially lost from small sediment grains due to alpha recoil, we found that (234U/238U) activity ratios generally decrease with age, depth, and specific surface area, with depletions of up to 9percent relative to radioactive equilibrium. The resulting calculated comminution ages are reasonable, although they do not exactly match age estimates from previous studies and also depend on assumptions about 234U loss rates. The results indicate that the method may be a significant addition to the sparse set of available tools for dating detrital continental sediments, following further refinement. Improving the accuracy of the method requires more advanced models or measurements for both the recoil loss factor fa and weathering effects. We discuss several independent methods for obtaining fa on individual samples

  14. There is no age limit for methadone: a retrospective cohort study

    PubMed Central

    2011-01-01

    Background Data from the US indicates that methadone-maintained populations are aging, with an increase of patients aged 50 or older. Data from European methadone populations is sparse. This retrospective cohort study sought to evaluate the age trends and related developments in the methadone population of Basel-City, Switzerland. Methods The study included methadone patients between April 1, 1995 and March 31, 2003. Anonymized data was taken from the methadone register of Basel-City. For analysis of age distributions, patient samples were split into four age categories from '20-29 years' to '50 years and over'. Cross-sectional comparisons were performed using patient samples of 1996 and 2003. Results Analysis showed a significant increase in older patients between 1996 and 2003 (p < 0.001). During that period, the percentage of patients aged 50 and over rose almost tenfold, while the proportion of patients aged under 30 dropped significantly from 52.8% to 12.3%. The average methadone dose (p < 0.001) and the 1-year retention rate (p < 0.001) also increased significantly. Conclusions Findings point to clear trends in aging of methadone patients in Basel-City which are comparable, although less pronounced, to developments among US methadone populations. Many unanswered questions on medical, psychosocial and health economic consequences remain as the needs of older patients have not yet been evaluated extensively. However, older methadone patients, just as any other patients, should be accorded treatment appropriate to their medical condition and needs. Particular attention should be paid to adequate solutions for persons in need of care. PMID:21592331

  15. Study on the thermal deactivation of motorcycle catalytic converters by laboratory aging tests.

    PubMed

    Chen, Yi-Chi; Chen, Lu-Yen; Yu, Yi-Hsien; Jeng, Fu-Tien

    2010-03-01

    Catalytic converters are used to curb exhaust pollution from motorcycles in Taiwan. A number of factors, including the length of time the converter is used for and driving conditions, affect the catalysts' properties during periods of use. The goal of this study is to resolve the thermal deactivation mechanism of motorcycle catalytic converters. Fresh catalysts were treated under different aging conditions by laboratory-scale aging tests to simulate the operation conditions of motorcycle catalytic converters. The aged catalysts were characterized by analytical techniques in order to provide information for investigating deactivation phenomena. The time-dependent data of specific surface areas were subsequently used to construct kinetics of sintering at the specific temperature. According to the analytical results of the catalysts' properties, the increase in aging temperature causes an increase in pore size of the catalysts and a decrease in the specific surface area. The aged catalysts all exhibited lower performances than the fresh ones. The reduction in catalytic activity is consistent with the reduction in the loss of specific surface area. The finding of catalytic properties' dependence on temperature is consistent with the thermally activated theory. In contrast, the effect of the aging time on the specific surface area was only significant during the initial few hours. The high correlation between specific surface areas measured by the Brunauer-Emmett-Teller (BET) method and predicted by the constructed model verifies that the prediction models can predict the sintering rate reasonably under the aging conditions discussed in this study. As compared to automobile catalytic converters, the differences of structures and aging conditions are made less obvious by the deactivation phenomena of motorcycles.

  16. Approaches to Investigating Complex Genetic Traits in a Large Scale Inbred Mouse Aging Study

    PubMed Central

    Sundberg, John P.; Berndt, Annerose; Sundberg, Beth A.; Silva, Kathleen A.; Kennedy, Victoria; Smith, Richard S.; Cooper, Timothy K.; Schofield, Paul N.

    2017-01-01

    Inbred mice are a unique model system for studying aging because of the genetic homogeneity within inbred strains, the short life span of mice relative to humans, and the rich array of analytical tools that are available. A large-scale aging study was conducted on 28 inbred strains representing great genetic diversity to determine, using histopathology, the type and diversity of spontaneous diseases aging mice develop. Eighteen inbred strains have had their genomes sequenced and many others have been partially sequenced to provide large repositories of data on genetic variation between the strains. This vast amount of genomic information can be utilized in genome-wide association studies (GWAS) to find candidate genes that are involved in the pathogenesis of spontaneous diseases. We present here, as an illustration, a GWAS of the genetic associations of age-related intestinal amyloidosis which implicates three candidate genes Tram1, Sf3b5, and Stx11. Many of the age-related mouse diseases are similar, if not identical, to human diseases and therefore the genetic discoveries have direct translational benefit. Representative photomicrographs are available on the Mouse Tumor Biology Database and Pathbase to serve as a reference when evaluating inbred mice used in other genetic or experimental studies to rule out strain background lesions. PMID:26936752

  17. The NAS Parallel Benchmarks 2.1 Results

    NASA Technical Reports Server (NTRS)

    Saphir, William; Woo, Alex; Yarrow, Maurice

    1996-01-01

    We present performance results for version 2.1 of the NAS Parallel Benchmarks (NPB) on the following architectures: IBM SP2/66 MHz; SGI Power Challenge Array/90 MHz; Cray Research T3D; and Intel Paragon. The NAS Parallel Benchmarks are a widely-recognized suite of benchmarks originally designed to compare the performance of highly parallel computers with that of traditional supercomputers.

  18. An overview of the design, implementation, and analyses of longitudinal studies on aging.

    PubMed

    Newman, Anne B

    2010-10-01

    Longitudinal studies have contributed substantially to understanding of aging and geriatric syndromes. These efforts have provided a base of knowledge of the critical factors to consider in designing and implementing new longitudinal studies in older adults. This review highlights some of the major considerations in planning and implementing this type of study. Longitudinal studies can assess change over time and specific disease endpoints. Such projects require multidisciplinary teams with expertise in the many health and contextual factors that must be considered. Recent advances in study design include the use of imaging and biomarkers to assess mechanisms and approaches that raise the ceiling on measurement and integrate assessment of exposures over time. Study implementation requires careful planning and monitoring to maintain fidelity to the scientific goals. Analysis of longitudinal data requires approaches that account for inevitable missing data. New studies should take advantage of the experience obtained from longitudinal studies on aging already conducted.

  19. 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

  20. Differences in tooth shade value according to age, gender and skin color: A pilot study

    PubMed Central

    Veeraganta, Sumanth K.; Savadi, Ravindra C.; Baroudi, Kusai; Nassani, Mohammad Z.

    2015-01-01

    Purpose of the Study: The purpose was to investigate the differences in tooth shade value according to age, gender and skin color among a sample of the local population in Bengaluru, India. Methodology: The study comprised 100 subjects belonging to both gender between the age groups of 16 years to 55 years. Tooth shade values of permanent maxillary left or right central incisors were recorded using the Vitapan 3D-Master shade guide. Skin color was matched using the Radiance compact makeup shades as a guide. Results: Chi-square statistical test demonstrated that younger subjects have lighter tooth shade values. No statistically significant differences were recorded in tooth shade value according to gender or skin color. Conclusion: Within the limitations of the current study, it can be concluded that tooth shade value is significantly influenced by age. Gender and skin color appear not to have a significant relation to tooth shade value. PMID:26929500

  1. Natural attenuation software (NAS): Assessing remedial strategies and estimating timeframes

    USGS Publications Warehouse

    Mendez, E.; Widdowson, M.; Chapelle, F.; Casey, C.

    2005-01-01

    Natural Attenuation Software (NAS) is a screening tool to estimate remediation timeframes for monitored natural attenuation (MNA) and to assist in decision-making on the level of source zone treatment in conjunction with MNA using site-specific remediation objectives. Natural attenuation processes that NAS models include are advection, dispersion, sorption, non-aqueous phase liquid (NAPL) dissolution, and biodegradation of either petroleum hydrocarbons or chlorinated ethylenes. Newly-implemented enhancements to NAS designed to maximize the utility of NAS for site managers were observed. NAS has expanded source contaminant specification options to include chlorinated ethanes and chlorinated methanes, and to allow for the analysis of any other user-defined contaminants that may be subject to microbially-mediated transformations (heavy metals, radioisotopes, etc.). Included is the capability to model co-mingled plumes, with constituents from multiple contaminant categories. To enable comparison of remediation timeframe estimates between MNA and specific engineered remedial actions , NAS was modified to incorporate an estimation technique for timeframes associated with pump-and-treat remediation technology for comparison to MNA. This is an abstract of a paper presented at the 8th International In Situ and On-Site Bioremediation Symposium (Baltimore, MD 6/6-9/2005).

  2. Consistency of TTO-NAS inorganic carbon data with modern measurements

    NASA Astrophysics Data System (ADS)

    Tanhua, Toste; Wallace, Douglas W. R.

    2005-07-01

    We compare alkalinity and total dissolved inorganic carbon (DIC) measurements made during the Transient Tracers in the Ocean, North Atlantic Study (TTO-NAS) in 1981 with modern measurements from a TTO reoccupation cruise in 2004 (M60/5). We find that the TTO-NAS alkalinity values are 3.6 +/- 2.3 μmol kg-1 higher than modern alkalinity data tied to Certified Reference Materials. The TTO-NAS DIC values re-calculated from original alkalinity and discrete-pCO2 data using currently accepted constants are 3.8 μmol kg-1 higher than those reported in the revised TTO data set. This difference is reduced to 0.7 μmol kg-1 when our suggested correction to the TTO-NAS alkalinity is applied. These re-calculated DIC values are 2.4 μmol kg-1 too low relative to contemporaneous measurements made by the vacuum extraction/manometric Certified method. Application of this correction brings the TTO data into almost perfect agreement with modern measurements for slowly-ventilated deep water of the eastern Atlantic.

  3. 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.

  4. Study of the degradation of gelatin in paper upon aging using aqueous size-exclusion chromatography.

    PubMed

    Dupont, Anne-Laurence

    2002-03-15

    We studied the aging behaviour of gelatin used to size paper. Thus far, research on the aging of paper has largely ignored the sizing agent. Degradation of the protein was characterised and the impact of paper components, such as cellulose, and aluminium potassium sulphate was evaluated. Whatman No. 1 filter papers sized with two types of gelatins (A and B) were prepared as model samples. Commercially sized modern papers (Arches) were also studied in order to compare laboratory samples with real artist papers. Both types of papers were artificially aged (80 degrees C, 50% relative humidity for 35 and 94 days). Historic papers were included in the study in order to compare artificially aged with naturally aged gelatin. The aqueous extracts from the papers were characterised by aqueous size-exclusion chromatography (SEC) using four PL-Aquagel-OH columns and UV photodiode array detection at 220, 254 and 280 nm. Results showed that gelatin undergoes hydrolysis upon aging, type A gelatin showing a faster degradation rate than type B. The result was an increase in the lower-molar-mass fractions, under 50,000 g mol(-1), and especially in a characteristic fraction with a peak molecular mass (MP) of 14,000 g mol(-1). A significant decrease in the extraction yields of alpha-, beta- and gamma-chains occurred after aging. This was attributed to crosslinking, leading to the formation of less-soluble polypeptides with very high molar mass (>800,000 g mol(-1)) Less than 10% alum had no impact on the degradation rate; higher alum contents accelerated hydrolysis reactions.

  5. 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.

  6. Two-wave longitudinal findings from the Berlin aging study: introduction to a collection of articles.

    PubMed

    Smith, Jacqui; Maas, Ineke; Mayer, Karl Ulrich; Helmchen, Hanfried; Steinhagen-Thiessen, Elisabeth; Baltes, Paul B

    2002-11-01

    We provide background information for a collection of articles that describe two-wave longitudinal findings derived from the first intensive follow-up of participants of the Berlin Aging Study (BASE). Multidisciplinary data were collected during 1995-1996 from 206 survivors approximately 4 years after baseline assessment (1990-1993). The strengths of the initial BASE design, in terms of a focus on very old age, multidisciplinary intensive assessment, and an examination of selectivity issues, were maintained in this longitudinal extension of the study.

  7. Age as a Risk Factor for Burnout Syndrome in Nursing Professionals: A Meta-Analytic Study.

    PubMed

    Gómez-Urquiza, José L; Vargas, Cristina; De la Fuente, Emilia I; Fernández-Castillo, Rafael; Cañadas-De la Fuente, Guillermo A

    2017-04-01

    Although past research has highlighted the possibility of a direct relationship between the age of nursing professionals and burnout syndrome, results have been far from conclusive. The aim of this study was to conduct a wider analysis of the influence of age on the three dimensions of burnout syndrome (emotional exhaustion, depersonalization, and personal accomplishment) in nurses. We performed a meta-analysis of 51 publications extracted from health sciences and psychology databases that fulfilled the inclusion criteria. There were 47 reports of information on emotional exhaustion in 50 samples, 39 reports on depersonalization for 42 samples, and 31 reports on personal accomplishment in 34 samples. The mean effect sizes indicated that younger age was a significant factor in the emotional exhaustion and depersonalization of nurses, although it was somewhat less influential in the dimension of personal accomplishment. Because of heterogeneity in the effect sizes, moderating variables that might explain the association between age and burnout were also analyzed. Gender, marital status, and study characteristics moderated the relationship between age and burnout and may be crucial for the identification of high-risk groups. More research is needed on other variables for which there were only a small number of studies. Identification of burnout risk factors will facilitate establishment of burnout prevention programs for nurses. © 2016 Wiley Periodicals, Inc.

  8. 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

  9. 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

  10. Ageing and COPD affect different domains of nutritional status: the ECCE study.

    PubMed

    Battaglia, S; Spatafora, M; Paglino, G; Pedone, C; Corsonello, A; Scichilone, N; Antonelli-Incalzi, R; Bellia, V

    2011-06-01

    Chronic obstructive pulmonary disease (COPD) and ageing may contribute to malnutrition. We aimed to explore whether COPD and ageing determine malnutrition in different manners. 460 stable COPD outpatients (376 males and 84 females) from the Extrapulmonary Consequences of COPD in the Elderly (ECCE) study database were investigated (age 75.0±5.9 yrs; forced expiratory volume in 1 s 54.7±18.3% predicted). Nutritional status was evaluated using the Mini Nutritional Assessment® (MNA) questionnaire. From the MNA, three scores exploring the domains of the nutritional status were calculated: body composition, energy intake and body functionality scores. Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages were negatively correlated with five MNA items exploring mobility, patient's perception of own nutrition and health status, and arm and calf circumferences (lowest Spearman's rho (rs)=-0.011; highest p=0.039). GOLD stages were independently correlated with body composition and body functionality scores (model r2=0.073). Age was negatively correlated with four MNA items exploring loss of appetite, fluid intake, mobility and autonomy in daily life (lowest rs=-0.013; highest p=0.030). Age was independently correlated with body functionality score (model r2=0.037). Severe COPD and ageing are independent and probably concurrent conditions leading to malnutrition. The MNA questionnaire allows a valuable insight into the complexity of components of nutritional status and may provide useful clues for treatment strategies.

  11. A longitudinal study of cryptosporidiosis in dairy cattle from birth to 2 years of age.

    PubMed

    Santín, Mónica; Trout, James M; Fayer, Ronald

    2008-08-01

    Fecal specimens were collected from 30 calves from birth to 24 months of age at a dairy farm in Maryland to determine the prevalence and age distribution of Cryptosporidium species/genotypes. After centrifugation to remove debris and concentrate oocysts, specimens were examined by immunofluorescence microscopy and polymerase chain reaction (PCR). Fragments of the SSU-rDNA gene amplified by PCR were purified and PCR products were sequenced. All 30 calves shed Cryptosporidium oocysts at some time during the 24 months of the study. Of 990 specimens, 190 were Cryptosporidium-positive (19.2%). The highest prevalence of infection was at 2 weeks of age when 29 of the 30 calves were excreting oocysts. Prevalence was higher in pre-weaned calves (1-8 weeks of age) (45.8%) than in post-weaned calves (3-12 months of age) (18.5%) and heifers (12-24 months of age) (2.2%). Sequence data for 190 PCR-positive specimens identified: C. parvum, C. bovis, the Cryptosporidium deer-like genotype and C. andersoni, with cumulative prevalences of 100, 80, 60, and 3.3%, respectively. C. parvum constituted 97% of infections in pre-weaned calves but only 4% and 0% of infections in post-weaned calves and heifers, respectively. All C. parvum GP60 nucleotide sequences were subtype IIaA15G2R1.

  12. Rejuvenation of Gene Expression Pattern of Aged Human Skin by Broadband Light Treatment: A Pilot Study

    PubMed Central

    Chang, Anne Lynn S; Bitter, Patrick H; Qu, Kun; Lin, Meihong; Rapicavoli, Nicole A; Chang, Howard Y

    2013-01-01

    Studies in model organisms suggest that aged cells can be functionally rejuvenated, but whether this concept applies to human skin is unclear. Here we apply 3′-end sequencing for expression quantification (“3-seq”) to discover the gene expression program associated with human photoaging and intrinsic skin aging (collectively termed “skin aging”), and the impact of broadband light (BBL) treatment. We find that skin aging was associated with a significantly altered expression level of 2,265 coding and noncoding RNAs, of which 1,293 became “rejuvenated” after BBL treatment; i.e., they became more similar to their expression level in youthful skin. Rejuvenated genes (RGs) included several known key regulators of organismal longevity and their proximal long noncoding RNAs. Skin aging is not associated with systematic changes in 3′-end mRNA processing. Hence, BBL treatment can restore gene expression pattern of photoaged and intrinsically aged human skin to resemble young skin. In addition, our data reveal, to our knowledge, a previously unreported set of targets that may lead to new insights into the human skin aging process. PMID:22931923

  13. Childhood diet and asthma and atopy at 8 years of age: the PIAMA birth cohort study.

    PubMed

    Willers, S M; Wijga, A H; Brunekreef, B; Scholtens, S; Postma, D S; Kerkhof, M; de Jongste, J C; Smit, H A

    2011-05-01

    Diet may affect the development of asthma. We investigated whether asthma or atopy outcomes at 8 yrs of age were associated with long-term dietary exposure, and whether associations were different for consumption at early or later age. The Prevention and Incidence of Asthma and Mite Allergy (PIAMA) birth cohort enrolled 4,146 participants at baseline, who were followed up to 8 yrs of age. Dietary intakes of interest were fruit, vegetables, brown/wholemeal bread, fish, milk, butter and margarine. Associations between food intake at early (2-3 yrs) and later (7-8 yrs) age, and long-term intake, asthma and atopy at 8 yrs of age were calculated by logistic regression. Complete longitudinal dietary data for at least one of the food groups were available for 2,870 children. Fruit consumption at early age was associated with reduced asthma symptoms (OR per 1 consumption day per week increase 0.93, 95% CI 0.85-1.00). Long-term fruit intake was inversely associated with asthma symptoms (OR 0.90, 95% CI 0.82-0.99) and sensitisation to inhaled allergens (OR 0.90, 95% CI 0.82-0.99). We found no consistent associations between diet and outcomes for other foods. This study indicates no consistent effects of increased early or late consumption, or long-term intake of certain foods on asthma and atopy in 8-yr-olds, with a possible exception for fruit.

  14. Age-dependent impairment of auditory processing under spatially focused and divided attention: an electrophysiological study.

    PubMed

    Wild-Wall, Nele; Falkenstein, Michael

    2010-01-01

    By using event-related potentials (ERPs) the present study examines if age-related differences in preparation and processing especially emerge during divided attention. Binaurally presented auditory cues called for focused (valid and invalid) or divided attention to one or both ears. Responses were required to subsequent monaurally presented valid targets (vowels), but had to be suppressed to non-target vowels or invalidly cued vowels. Middle-aged participants were more impaired under divided attention than young ones, likely due to an age-related decline in preparatory attention following cues as was reflected in a decreased CNV. Under divided attention, target processing was increased in the middle-aged, likely reflecting compensatory effort to fulfill task requirements in the difficult condition. Additionally, middle-aged participants processed invalidly cued stimuli more intensely as was reflected by stimulus ERPs. The results suggest an age-related impairment in attentional preparation after auditory cues especially under divided attention and latent difficulties to suppress irrelevant information.

  15. 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

  16. A statistical model for the study of U-Nb aging (u)

    SciTech Connect

    Hemphill, Geralyn M; Hackenberg, Robert E

    2009-01-01

    This study was undertaken to model the aging response of U-Nb alloys in order to quantify property and lifetime predictions and uncertainties, in response to concerns that aging during long-term stockpile storage may change the microstructure and properties of U-6 wt%Nb alloy components in ways adversely affecting performance. U-6Nb has many desirable properties, but is a complex material because of its gross compositional inhomogeneity (its chemical banding spans 4-8 wt%), its metastable starting microstructure, and the fact that a variety of external factors such as temperature, stress, and gaseous species can cause aging through multiple mechanisms. The most significant aging mechanism identified in earlier studies [2007hac2] is age hardening, phenomenologically defined as increasing hardness and strength and decreasing ductility observed as a function of increasing aging time-at-temperature. The scientific fundamentals of age hardening at temperatures relevant to U-6Nb material processing ({le}200 C) and stockpile storage ({le}60 C) remain unresolved in spite of significant experimental efforts [2007hac2, 2009cla]. Equally problematic is the lack of a well-established U-6Nb component failure criterion. These limitations make the most desirable approach of property response and lifetime prediction - that based on fundamental physics - unattainable at the present time. Therefore, a semi-empirical approach was taken to model the phenomenological property evolution during aging. This enabled lifetime estimates to be made from an assumed failure criterion (derived from a manufacturing acceptance criterion) couched in terms of an age-sensitive property, namely quasi-static tensile elongation to failure. The predictions of this and other age-sensitive properties are also useful for U-6Nb component surveillance studies. Drawing upon a large body of artificial aging data obtained from nonbanded (chemically homogeneous) U-5.6Nb and U-7.7Nb material [2007hacJ ] over 100

  17. Lessons from the Bone Chapter of the Malaysian Aging Men Study

    PubMed Central

    Chin, Kok-Yong; Wan Ngah, Wan Zurinah; Ima-Nirwana, Soelaiman

    2016-01-01

    Male osteoporosis in Malaysia is a largely neglected problem. Therefore, a bone health study in men using quantitative ultrasonometry was launched as part of the Malaysian Aging Men Study in 2009–2012. This review aimed to summarize the findings of the aforementioned bone health study. The study examined the bone health of Chinese and Malaysian men aged 20 years and above living in Kuala Lumpur using a quantitative ultrasound device. Participants answered a questionnaire on their demographic details and physical activity status. Body anthropometry of the participants was measured and their blood collected for biochemical analysis. Results showed that a significant proportion of the Malaysian Chinese and Malay men had suboptimal bone health indicated by calcaneal speed of sound and vitamin D status. Age-related decline of the calcaneal speed of sound in these men was gradual and biphasic without ethnic difference. Body anthropometry such as height, weight, body mass index, and body fat percentage contributed to the variation of the calcaneal speed of sound in Malaysian men. Age-related changes in testosterone, insulin-like growth factor 1, and thyroid stimulating hormone also influenced the calcaneal speed of sound in these men. This study serves as a reminder that male osteoporosis in Malaysia should be an issue of concern. It is also a basis for a more comprehensive study on bone health in men in the future. PMID:27231930

  18. Extensive occupational finger use delays age effects in tactile perception-an ERP study.

    PubMed

    Reuter, Eva-Maria; Voelcker-Rehage, Claudia; Vieluf, Solveig; Winneke, Axel H; Godde, Ben

    2014-05-01

    Tactile expertise, resulting from extensive use of hands, has previously been shown to improve tactile perception in blind people and musicians and to be associated with changes in the central processing of tactile information. This study investigated whether expertise, due to precise and deliberate use of the fingers at work, relates to improved tactile perception and whether this expertise interacts with age. A tactile pattern and a frequency discrimination task were conducted while ERPs were measured in experts and nonexperts of two age groups within middle adulthood. Independently of age, accuracy was better in experts than in nonexperts in both tasks. Somatosensory N70 amplitudes were larger with increasing age and for experts than for nonexperts. P100 amplitudes were smaller in experts than in nonexperts in the frequency discrimination task. In the pattern discrimination task, P300 difference wave amplitude was reduced in experts and late middle-aged adults. In the frequency discrimination task, P300 was more equally distributed in late middle-aged adults. We conclude that extensive, dexterous manual work leads to acquisition of tactile expertise and that this expertise might delay, but not counteract, age effects on tactile perception. Comparable neurophysiological changes induced by age and expertise presumably have different underlying mechanisms. Enlarged somatosensory N70 amplitudes might result from reduced inhibition in older adults but from enhanced, specific excitability of the somatosensory cortex in experts. Regarding P300, smaller amplitudes might indicate fewer available resources in older adults and, by contrast, a reduced need to engage as much cognitive effort to the task in experts.

  19. Mechanism of Origin of Conduction Disturbances in Aging Human Atrial Bundles: Experimental and Model Study

    PubMed Central

    Spach, Madison S.; Heidlage, J. Francis; Dolber, Paul C.; Barr, Roger C.

    2007-01-01

    BACKGROUND Aging is associated with a significant increase in atrial tachyarrhythmias, especially atrial fibrillation. A macroscopic repolarization gradient created artificially by a stimulus at one site prior to a premature stimulus from a second site is widely considered to be part of the experimental protocol necessary for the initiation of such arrhythmias in the laboratory. How such gradients occur naturally in aging atrial tissue has remained unknown. OBJECTIVE This study was to determine if the pattern of cellular connectivity in aging human atrial bundles produces a mechanism for variable early premature responses. METHODS Extracellular and intracellular potentials were recorded following control and premature stimuli at a single site in aging human atrial bundles. We also measured cellular geometry, the distribution of connexins, and the distribution of collagenous septa. A model of the atrial bundles was constructed based on the morphological results. Action potential propagation and the sodium current were analyzed following premature stimuli in the model. RESULTS Similar extracellular potential waveform responses occurred following early premature stimuli in the aging bundles and in the model. Variable premature conduction patterns were accounted for by the single model of aging atrial structure. A major feature of the model results was that the conduction events and the magnitude of the sodium current at multiple sites were very sensitive to small changes in the location and the timing of premature stimuli. CONCLUSION In aging human atrial bundles stimulated from only a single site, premature stimuli induce variable arrhythmogenic conduction responses. The generation of these responses is greatly enhanced by remodeling of cellular connectivity during aging. The results provide insight into sodium current-structural interactions as a general mechanism of arrhythmogenic atrial responses to premature stimuli. PMID:17275753

  20. Mature age students access, entry and success in nurse education: an action research study.

    PubMed

    Kenny, Amanda; Kidd, Tracy; Nankervis, Katrina; Connell, Sarah

    2011-01-01

    This action research study involved an 'expert group' that was convened to consider issues for mature age nursing students in the Australian context and develop recommendations that could be used to strengthen mature age entry, access and success in nursing programs. Consistent with action research, the group worked through phases of planning, action, observation, evaluation and critical reflection. In developing recommendations that could be used for future planning, the group met regularly, reviewed extensive literature, and conducted two data collection activities, a questionnaire and focus group with education providers. From the action research activities, five major recommendations were generated. These focused on the value of mature age students, the need for specific information, transparent and clear processes for students entering nurse education, study support and finally, the provision of financial assistance.

  1. Resilient offspring of alcoholics: a longitudinal study from birth to age 18.

    PubMed

    Werner, E E

    1986-01-01

    This study focuses on child characteristics and on the qualities of the caregiving environment that differentiated between offspring of alcoholics who did and those who did not develop serious coping problems by age 18. The 49 subjects (22 male) are members of a multiracial cohort of 698 children born in 1955 on the island of Kauai, Hawaii, who were followed at ages 1, 2, 10 and 18. In this group, males and the offspring of alcoholic mothers had higher rates of psychosocial problems in childhood and adolescence than females and the offspring of alcoholic fathers. Children of alcoholics who developed no serious coping problems by age 18 differed from those who did in characteristics of temperament, communication skills, self-concept and locus of control. They had also experienced fewer stressful life events disrupting their family unit in the first two years of life. Results of the study support a transactional model of human development and demonstrate bidirectionality of child-caregiver effects.

  2. Genetic studies of Age-related macular degeneration: lessons, challenges and opportunities for disease management

    PubMed Central

    Ratna Priya, Rinki; Chew, Emily Y.; Swaroop, Anand

    2012-01-01

    Age-related macular degeneration (AMD) is a common cause of visual impairment in individuals over 55 years of age worldwide. The varying clinical phenotypes of AMD result from contributions of genetic, epigenetic and non-genetic (environmental) factors. Genetic studies of AMD have come of age as a direct result of tremendous gains from human genome project, genomewide association studies and identification of numerous susceptibility loci. These findings have implicated immune response, high-density lipoprotein cholesterol metabolism, extracellular matrix, and angiogenesis signaling pathways in disease pathophysiology. Here, we address how the wealth of genetic findings in AMD is expected to impact the practice of medicine, providing opportunities for improved risk assessment, molecular diagnosis, preventive and therapeutic intervention. We propose that the potential of using genetic variants for monitoring treatment response (pharmacogenetics) may usher a new era of personalized medicine in the clinical management of AMD. PMID:23009893

  3. 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

  4. 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.

  5. Impact of sex and age on the performance of FINDRISC: the HUNT Study in Norway

    PubMed Central

    Midthjell, Kristian; Holmen, Jostein; Tuomilehto, Jaakko; Carlsen, Sven M; Shaw, Jonathan; Åsvold, Bjørn O

    2016-01-01

    Objective The Finnish Diabetes Risk Score (FINDRISC) is recommended as a screening tool for diabetes risk. However, there is a lack of well-powered studies examining the performance of FINDRISC by sex and age. We aim to estimate, by sex and age, the prevalence of elevated FINDRISC and positive predictive value (PPV) of FINDRISC for identifying impaired glucose metabolism (IGM) in a general Norwegian population. Research design and methods We estimated the prevalence of elevated FINDRISC (≥15) among 47 694 adults in the third survey of the Nord-Trøndelag Health Study (HUNT3, 2006–08). Among 2559 participants who participated in oral glucose tolerance testing, we estimated the PPV of elevated FINDRISC for identifying unknown prevalent diabetes and other forms of IGM. Results The prevalence of elevated FINDRISC was 12.1% in women, 9.6% in men, and increased from 1.5% at age 20–39 to 25.1% at age 70–79 years. The PPVs of elevated FINDRISC were 9.8% for diabetes, 16.9% for impaired glucose tolerance, 8.2% for impaired fasting glucose, and 34.9% for any form of IGM. The PPV for IGM was lower in women (31.2%) than in men (40.4%), and increased from 19.1% at age 20–39 to 55.5% at age ≥80 years. Conclusions FINDRISC identified more women than men as high-risk individuals for diabetes. FINDRISC had a high PPV for detecting prevalent IGM, and the PPV was higher in men than in women and in the older individuals. Our data indicate that the impact of sex and age on diabetes risk is not fully captured by FINDRISC, and that refinements to it might improve diabetes prediction. PMID:27403326

  6. Age and Environment Determined Children’s Preference Towards Dentist Attire - A Cross - Sectional Study

    PubMed Central

    Gurunathan, Deepa; Karthikeyan, Shanmugaavel; Subbramanian, EMG; Samuel, Victor A

    2016-01-01

    Introduction The attire of the dentist has an influence on child’s behaviour in dental setup. Recent research has shown that the children have preferences towards the outfit worn by the dentist. Aim The aim of the study was to determine the preference of children towards dentists’ attire based on various age groups and environment. Materials and Methods A total of 534 children aged between 6-11 years participated in the study. Children were divided into three groups based on their age as younger, middle and older age groups. Photographs of the dentist in different attires such as white coat, surgical scrubs and regular outfit were shown to children and the questionnaire was evaluated by a single, qualified Paediatric dentist in two different environmental set ups, namely school and dental environment. The anxiety level was evaluated by using Modified Child Dental Anxiety Scale [MCDAS (f)]. Data was collected and tabulated. Statistical analysis was done using SPSS version 20.0. Results A statistically significant difference was evident in the preference level of children towards dentist attire (p-value= 0.002). There was a positive correlation in the preference level of children towards dentist attire in different age groups. A statistically significant difference was evident in the preference level of children towards the dentist attire in school and dental environment (p-value <0.001). Conclusion Younger age group children preferred regular outfit and middle and older age group preferred white coat and surgical scrubs respectively. Children preferred white coat in school environment and surgical scrubs in dental environment. PMID:27891450

  7. Survey of Aging Veterans: A Study of the Means, Resources and Future Expectations of Veterans Aged 55 and Over.

    ERIC Educational Resources Information Center

    Veterans Administration, Washington, DC. Office of Information Management and Statistics.

    A national survey of the needs, resources, and future expectations of veterans aged 55 and over produced findings that the Veterans Administration (VA) will use over the next decade to plan facilities and programs to meet those needs. Findings indicated veterans had a higher educational level and were less likely to be at the lower end of the…

  8. Dietary compound score and risk of age-related macular degeneration in the Age-Related Eye Disease Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Purpose: Because foods provide many nutrients, which may interact with each other to modify risk for multifactorial diseases such as age-related macular degeneration (AMD), we sought to develop a composite scoring system to summarize the combined effect of multiple dietary nutrients on AMD risk. Th...

  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. Study about the effects of different fitness sports on cognitive function and emotion of the aged.

    PubMed

    Zhang, Xinan; Ni, Xiaomei; Chen, Peijie

    2014-12-01

    The aim of the study was to explore the effects of different fitness sports on cognitive function and emotion of the aged people. A total of 150 subjects aged between 60 and 70 were recruited from Shenyang Aged University and elderly activity center. All subjects reported no fitness before this study. The aged subjects were divided into five groups, included swimming group (A group), running group (B group), square dancing group (C group), Tai Chi group (D group) and control group (E group) with 30 people in each group. Subjects in each group received exercise intervention continued for 18 months. At baseline, 6, 12 and 18 months after intervention, the P300 test, SECF, HAMD and HAMA scale evaluations were performed. Compared to E group, the P2, N2 and P3 latency and response time in the D group after intervention for 6 months, and in the A-C groups after intervention for 12 months were significantly prolonged. The anxiety symptom and depression levels in the A-D groups after intervention for 12 months were significantly decreased when compared to E group (P < 0. 01), where significantly improved compared with the E group (P < 0. 01). The effect of exercise intervention for Tai Chi group was the most significant. Different fitness sports have marked beneficial effect on cognitive function and emotion of the aged people, especially the Tai Chi exercise.

  11. Parental age and the origin of trisomy 21. A study of 302 families.

    PubMed

    Dagna Bricarelli, F; Pierluigi, M; Landucci, M; Arslanian, A; Coviello, D A; Ferro, M A; Strigini, P

    1989-04-01

    Several studies have attempted to define the role of parental age in determining the prevalence of 47, +21 according to the origin of nondisjunction. This report analyzes the original data of 197 informative families from Italy and reviews the available literature (96 families from Denmark and 201 from other countries). Mothers whose gametes showed nondisjunction are treated as cases, and those with normal meiosis as controls within each study. To utilize the data fully, maternal age at birth of a 47, +21 individual is treated as a continuous variable in a nonparametric comparison. The combined evidence indicates that nondisjunction in the female is associated with a significant age difference between cases and controls which is mostly due to errors in the second meiotic division. It may be inferred that in the general population, aging enhances nondisjunction at both first and second division in the female, while aging in the male is presumably associated mostly (or only) with first division errors. Implications and alternative models are discussed.

  12. The Longitudinal Aging Study Amsterdam: cohort update 2016 and major findings.

    PubMed

    Hoogendijk, Emiel O; Deeg, Dorly J H; Poppelaars, Jan; van der Horst, Marleen; Broese van Groenou, Marjolein I; Comijs, Hannie C; Pasman, H Roeline W; van Schoor, Natasja M; Suanet, Bianca; Thomése, Fleur; van Tilburg, Theo G; Visser, Marjolein; Huisman, Martijn

    2016-09-01

    The Longitudinal Aging Study Amsterdam (LASA) is an ongoing longitudinal study of older adults in the Netherlands, which started in 1992. LASA is focused on the determinants, trajectories and consequences of physical, cognitive, emotional and social functioning. The study is based on a nationally representative sample of older adults aged 55 years and over. The findings of the LASA study have been reported in over 450 publications so far (see www.lasa-vu.nl ). In this article we describe the background and the design of the LASA study, and provide an update of the methods. In addition, we provide a summary of the major findings from the period 2011-2015.

  13. Age adjustment in ecological studies: using a study on arsenic ingestion and bladder cancer as an example

    PubMed Central

    2011-01-01

    Background Despite its limitations, ecological study design is widely applied in epidemiology. In most cases, adjustment for age is necessary, but different methods may lead to different conclusions. To compare three methods of age adjustment, a study on the associations between arsenic in drinking water and incidence of bladder cancer in 243 townships in Taiwan was used as an example. Methods A total of 3068 cases of bladder cancer, including 2276 men and 792 women, were identified during a ten-year study period in the study townships. Three methods were applied to analyze the same data set on the ten-year study period. The first (Direct Method) applied direct standardization to obtain standardized incidence rate and then used it as the dependent variable in the regression analysis. The second (Indirect Method) applied indirect standardization to obtain standardized incidence ratio and then used it as the dependent variable in the regression analysis instead. The third (Variable Method) used proportions of residents in different age groups as a part of the independent variables in the multiple regression models. Results All three methods showed a statistically significant positive association between arsenic exposure above 0.64 mg/L and incidence of bladder cancer in men and women, but different results were observed for the other exposure categories. In addition, the risk estimates obtained by different methods for the same exposure category were all different. Conclusions Using an empirical example, the current study confirmed the argument made by other researchers previously that whereas the three different methods of age adjustment may lead to different conclusions, only the third approach can obtain unbiased estimates of the risks. The third method can also generate estimates of the risk associated with each age group, but the other two are unable to evaluate the effects of age directly. PMID:22014275

  14. Online Learning across Ethnicity and Age: A Study on Learning Interaction Participation, Perception, and Learning Satisfaction

    ERIC Educational Resources Information Center

    Ke, Fengfeng; Kwak, Dean

    2013-01-01

    This mixed-method study examined whether online learning interaction participation, perception, and learning satisfaction would be consistent across varied age and ethnicity groups. Data were collected from students enrolled in 28 online courses via content analysis with online interaction transcripts, structural equation modeling with the…

  15. Psychiatric Disorders in Extremely Preterm Children: Longitudinal Finding at Age 11 Years in the EPICure Study

    ERIC Educational Resources Information Center

    Johnson, Samantha; Hollis, Chris; Kochhar, Puja; Hennessy, Enid; Wolke, Dieter; Marlow, Neil

    2010-01-01

    Objective: To investigate the prevalence and risk factors for psychiatric disorders in extremely preterm children. Method: All babies born less than 26 weeks gestation in the United Kingdom and Ireland from March through December 1995 were recruited to the EPICure Study. Of 307 survivors at 11 years of age, 219 (71%) were assessed alongside 153…

  16. Language, Literacy and Numeracy in National Training Packages: Case Studies in Aged Care and Hospitality.

    ERIC Educational Resources Information Center

    Haines, Christine; Brand, Jennie Bickmore

    The implementation and effectiveness of the inclusion of literacy and numeracy in industry training packages was examined in case studies of three programs in Western Australia. Two were certificate programs in cooking and food and beverage as specified in the hospitality training package, and the third was an aged care program based on the…

  17. A Cross-Age Study of Children's Knowledge of Apparent Celestial Motion

    ERIC Educational Resources Information Center

    Plummer, Julia D.

    2009-01-01

    The US National Science Education Standards and the Benchmarks for Science Literacy recommend that students understand the apparent patterns of motion of the Sun, Moon, and stars by the end of early elementary school, yet no research has specifically examined these concepts from an Earth-based perspective with this age group. This study examines…

  18. Treatment Moderators and Predictors of Outcome in the Treatment of Early Age Mania (TEAM) Study

    ERIC Educational Resources Information Center

    Vitiello, Benedetto; Riddle, Mark A.; Yenokyan, Gayane; Axelson, David A.; Wagner, Karen D.; Joshi, Paramjit; Walkup, John T.; Luby, Joan; Birmaher, Boris; Ryan, Neal D.; Emslie, Graham; Robb, Adelaide; Tillman, Rebecca

    2012-01-01

    Objective: Both the diagnosis and treatment of bipolar disorder in youth remain the subject of debate. In the Treatment of Early Age Mania (TEAM) study, risperidone was more effective than lithium or divalproex in children diagnosed with bipolar mania and highly comorbid with attention-deficit/hyperactivity disorder (ADHD). We searched for…

  19. Gastric emptying scintigraphy results in children are affected by age, anthropometric factors, and study duration

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A standardized 4-hour adult-based gastric emptying scintigraphy (GES) protocol is increasingly being used in children to evaluate for gastroparesis. We sought to determine the effect of age, anthropometrics, and study duration on GES results using this protocol in children. Retrospective review of c...

  20. Relative Age Effects in a Cognitive Task: A Case Study of Youth Chess

    ERIC Educational Resources Information Center

    Helsen, Werner F.; Baker, Joseph; Schorer, Joerg; Steingröver, Christina; Wattie, Nick; Starkes, Janet L.

    2016-01-01

    The relative age effect (RAE) has been demonstrated in many youth and professional sports. In this study, we hypothesized that there would also be a RAE among youth chess players who are typically involved in a complex cognitive task without significant physical requirements. While typical RAEs have been observed in adult chess players, in this…

  1. Experiencing Term-Time Employment as a Non-Traditional Aged University Student: A Welsh Study

    ERIC Educational Resources Information Center

    Mercer, Jenny; Clay, James; Etheridge, Leanne

    2016-01-01

    Engaging in term-time employment appears to be becoming a common feature of contemporary UK student life. This study examined the ways in which a cohort of full-time non-traditional aged students negotiated paid employment whilst pursuing a full-time higher education course in Wales. Taking a qualitative approach to explore this further,…

  2. C-reactive protein and genetic variants and cognitive decline in old age: The PROSPER Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plasma concentrations of C-reactive protein (CRP), a marker of chronic inflammation, have been associated with cognitive impairment in old age. However, it is unknown whether CRP is causally linked to cognitive decline. Within the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER) tri...

  3. Developmental Norms of Children Aged 2 1/2-5 Years: A Pilot Study.

    ERIC Educational Resources Information Center

    Muralidharan, Rajalakshmi

    1969-01-01

    The purpose of this pilot study, aside from collection of developmental data on 38 nursery school children aged 2 1/2 to 5 years, was (1) to develop, modify and adapt the testing equipment used in Gesell's Developmental Schedule, in the field of motor, adaptive, language, and personal-social development; (2) to develop elaborate, exhaustive,…

  4. People Through the Ages. Social Studies Interim Grade Guide for Grade Eight.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education, Winnipeg. Curriculum Development Branch.

    Supplementary units of study help eighth graders in Manitoba explore the ways people lived within selected societies of the past and realize that life today is closely related to developments which have occurred through the ages. Units and subtopics are: (1) Life during Prehistoric and Early Historic Times--prehistoric times, life in early river…

  5. Language Maintenance and Loss in Preschool-Age Children of Mexican Immigrants: Longitudinal Study

    ERIC Educational Resources Information Center

    Guiberson, Mark M.; Barrett, Karen C.; Jancosek, Elizabeth G.; Itano, Christine Yoshinaga

    2006-01-01

    In this study, the authors plotted the Spanish language usage of 10 preschool-age children over the course of 3 years and assigned them to one of two groups: language maintenance and language loss. The authors then compared the groups' scores on structured tasks, language behaviors, and language usage/exposure variables. They found that children…

  6. Does Gender Matter? An Exploratory Study of Perspectives across Genders, Age and Education

    ERIC Educational Resources Information Center

    Carinci, Sherrie; Wong, Pia Lindquist

    2009-01-01

    Using a convenience sample and survey research methods, the authors seek to better understand how perspectives on gender are shaped by individuals' age, level of education and gender. Study participants responded in writing to scenarios and survey questions, revealing their personal views on gender as an identity category and as a marker in the…

  7. The National Treatment Improvement Evaluation Study (NTIES): Profile of Clients Age 45 and Over.

    ERIC Educational Resources Information Center

    Caliber Associates, Fairfax, VA.

    This paper summarizes similarities and differences between two cohorts of the National Treatment Improvement Evaluation Study (NTIES) clients, those age 45 or older and those younger than 45. Results reveal the following: Clients in the 45+ cohort were considerably more likely to be treated for problems with alcohol or with heroin, and they were…

  8. Effects of Aging on True and False Memory Formation: An fMRI Study

    ERIC Educational Resources Information Center

    Dennis, Nancy A.; Kim, Hongkeun; Cabeza, Roberto

    2007-01-01

    Compared to young, older adults are more likely to forget events that occurred in the past as well as remember events that never happened. Previous studies examining false memories and aging have shown that these memories are more likely to occur when new items share perceptual or semantic similarities with those presented during encoding. It is…

  9. Planning for End-of-Life Care: Findings from the Canadian Study of Health and Aging

    ERIC Educational Resources Information Center

    Garrett, Douglas D.; Tuokko, Holly; Stajduhar, Kelli I.; Lindsay, Joan; Buehler, Sharon

    2008-01-01

    Steps involved in formalizing end-of-life care preferences and factors related to these steps are unclear in the literature. Using data from the third wave of the Canadian Study of Health and Aging (CSHA-3), we examined the relations between demographic and health predictors, on the one hand, and three outcomes, on the other (whether participants…

  10. Traditional-Aged College Juniors' Career Planning Self-Efficacy: A Case Study

    ERIC Educational Resources Information Center

    Sherman, Dawn C.

    2012-01-01

    The purpose of this single-site case study was to explore and describe traditional-age college juniors' reports of self-efficacy (Bandura, 1997) regarding Career Planning (Barker & Kellen, 1998). More specifically, the career planning confidence levels of college juniors enrolled in a required career development course at a private business…

  11. Culture and diet among Chinese American children aged 9–13 years: A qualitative study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined Chinese American children's behaviors, food preferences, and cultural influences on their diet. Qualitative individual interviews were conducted with twenty-five Chinese American children aged 9-13 years in community centers and Chinese schools in Houston, TX using constructs fro...

  12. Keep Your Brain Fit! A Psychoeducational Training Program for Healthy Cognitive Aging: A Feasibility Study

    ERIC Educational Resources Information Center

    Reijnders, Jennifer; van Heugten, Caroline; van Boxtel, Martin

    2015-01-01

    A psychoeducational face-to-face training program (Keep Your Brain Fit!) was developed to support the working population in coping with age-related cognitive changes and taking proactive preventive measures to maintain cognitive health. A feasibility study was conducted to test the training program presented in a workshop format. Participants…

  13. Successful Aging in a 70-Year-Old Man with Down Syndrome: A Case Study

    ERIC Educational Resources Information Center

    Krinsky-McHale, Sharon J.; Devenny, Darlynne A.; Gu, Hong; Jenkins, Edmund C.; Kittler, Phyllis; Murty, Vundavalli V.; Schupf, Nicole; Scotto, Luigi; Tycko, Benjamin; Urv, Tiina K.; Ye, Lingling; Zigman, Warren B.; Silverman, Wayne

    2008-01-01

    The authors present a case study of a 70-year-old man with Down syndrome ("Mr. C.") who they followed for 16 years and who does not exhibit declines in cognitive or functional capacities indicative of dementia, despite having well-documented, complete trisomy 21. The authors describe the age-associated changes that occurred over 16 years as well…

  14. Ageing and Dementia in a Longitudinal Study of a Cohort with Down Syndrome

    ERIC Educational Resources Information Center

    Carr, Janet; Collins, Suzanne

    2014-01-01

    Background: A population sample of people with Down syndrome has been studied from infancy and has now been followed up again at age 47 years. Methods: Intelligence and language skills were tested and daily living skills assessed. Memory/cognitive deterioration was examined using two test instruments. Results: Scores on verbal tests of…

  15. Middle-Aged Independent-Living African Americans' Selections for Advance Directives: A Case Study

    ERIC Educational Resources Information Center

    McDaniel, Brenda J.

    2013-01-01

    The purpose of this collective embedded qualitative case study was to examine the perspectives of three middle-aged independent-living African Americans who had participated in the process of advance care planning (ACP) and completed at least two advance directives (ADs), a Durable Power of Attorney for Health Care (DPAHC) and a Living Will (LW).…

  16. Age determination and validation studies of marine fishes: do deep-dwellers live longer?

    PubMed

    Cailliet, G M; Andrews, A H; Burton, E J; Watters, D L; Kline, D E; Ferry-Graham, L A

    2001-04-01

    Age determination and validation studies on deep-water marine fishes indicate they are difficult to age and often long-lived. Techniques for the determination of age in individual fish includes growth-zone analysis of vertebral centra, fin rays and spines, other skeletal structures, and otoliths (there are three sets of otoliths in most bony fish semicircular canals, each of which is made of calcium carbonate). Most have regular increments deposited as the fish (and its semicircular canals) grows. The most commonly used otolith for age determination is the largest one called the sagitta. Age validation techniques include: (1) tag-recapture, often combined with oxytetracycline injection and analysis in growth-zones of bone upon recapture; (2) analysis of growth-zones over time; and (3) radiometric approaches utilizing a known radioactive decay series as an independent chronometer in otoliths from bony fishes. We briefly summarize previous studies using these three validation approaches and present results from several of our radiometric studies on deep-water, bony fishes recently subjected to expanding fisheries. Radiometric age validation results are presented for four species of scorpaenid fishes (the bank, Sebastes rufus, and bocaccio, S. paucispinis, rockfishes, and two thornyhead species, Sebastolobus altivelis and S. alascanus). In addition, our analysis of scorpaenids indicates that longevity increases exponentially with maximum depth of occurrence. The reason that the deep-water forms of scorpaenid fishes are long-lived is uncertain. Their longevity, however, may be related to altered physiological processes relative to environmental parameters like low temperature, high pressures, low light levels, low oxygen, and poor food resources.

  17. Regional and Gender Study of Neuronal Density in Brain during Aging and in Alzheimer's Disease

    PubMed Central

    Martínez-Pinilla, Eva; Ordóñez, Cristina; del Valle, Eva; Navarro, Ana; Tolivia, Jorge

    2016-01-01

    Background: Learning processes or language development are only some of the cognitive functions that differ qualitatively between men and women. Gender differences in the brain structure seem to be behind these variations. Indeed, this sexual dimorphism at neuroanatomical level is accompanied unequivocally by differences in the way that aging and neurodegenerative diseases affect men and women brains. Objective: The aim of this study is the analysis of neuronal density in four areas of the hippocampus, and entorhinal and frontal cortices to analyze the possible gender influence during normal aging and in Alzheimer's disease (AD). Methods: Human brain tissues of different age and from both sexes, without neurological pathology and with different Braak's stages of AD, were studied. Neuronal density was quantified using the optical dissector. Results: Our results showed the absence of a significant neuronal loss during aging in non-pathological brains in both sexes. However, we have demonstrated specific punctual significant variations in neuronal density related with the age and gender in some regions of these brains. In fact, we observed a higher neuronal density in CA3 and CA4 hippocampal areas of non-pathological brains of young men compared to women. During AD, we observed a negative correlation between Braak's stages and neuronal density in hippocampus, specifically in CA1 for women and CA3 for men, and in frontal cortex for both, men and women. Conclusion: Our data demonstrated a sexual dimorphism in the neuronal vulnerability to degeneration suggesting the need to consider the gender of the individuals in future studies, regarding neuronal loss in aging and AD, in order to avoid problems in interpreting data. PMID:27679571

  18. Analysis, prediction, and case studies of early-age cracking in bridge decks

    NASA Astrophysics Data System (ADS)

    ElSafty, Adel; Graeff, Matthew K.; El-Gharib, Georges; Abdel-Mohti, Ahmed; Mike Jackson, N.

    2016-06-01

    Early-age cracking can adversely affect strength, serviceability, and durability of concrete bridge decks. Early age is defined as the period after final setting, during which concrete properties change rapidly. Many factors can cause early-age bridge deck cracking including temperature change, hydration, plastic shrinkage, autogenous shrinkage, and drying shrinkage. The cracking may also increase the effect of freeze and thaw cycles and may lead to corrosion of reinforcement. This research paper presents an analysis of causes and factors affecting early-age cracking. It also provides a tool developed to predict the likelihood and initiation of early-age cracking of concrete bridge decks. Understanding the concrete properties is essential so that the developed tool can accurately model the mechanisms contributing to the cracking of concrete bridge decks. The user interface of the implemented computer Excel program enables the user to input the properties of the concrete being monitored. The research study and the developed spreadsheet were used to comprehensively investigate the issue of concrete deck cracking. The spreadsheet is designed to be a user-friendly calculation tool for concrete mixture proportioning, temperature prediction, thermal analysis, and tensile cracking prediction. The study also provides review and makes recommendations on the deck cracking based mainly on the Florida Department of Transportation specifications and Structures Design Guidelines, and Bridge Design Manuals of other states. The results were also compared with that of other commercially available software programs that predict early-age cracking in concrete slabs, concrete pavement, and reinforced concrete bridge decks. The outcome of this study can identify a set of recommendations to limit the deck cracking problem and maintain a longer service life of bridges.

  19. Sex ratio of congenital abnormalities in the function of maternal age: a population-based study.

    PubMed

    Csermely, Gyula; Urbán, Robert; Czeizel, Andrew E; Veszprémi, Béla

    2015-05-01

    Maternal age effect is well-known in the origin of numerical chromosomal aberrations and some isolated congenital abnormalities (CAs). The sex ratio (SR), i.e. number of males divided by the number of males and females together, of most CAs deviates from the SR of newborn population (0.51). The objective of this analysis was to evaluate the possible association of maternal age with the SR of isolated CAs in a population-based large dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. First, SR of 24 CA entities/groups was estimated in 21,494 patients with isolated CA. In the next step SR of different maternal age groups was compared to the mean SR of the given CA-groups. The SR of four CA-groups showed some deviation in certain maternal age groups. Cases with anencephaly had female excess in young mothers (<25 years). Cases with skull's CAs particularly craniosynostosis had a male excess in cases born to women over 30 years. Two other CA groups (cleft lip ± palate and valvar pulmonic stenosis within the group of right-sided obstructive defect of heart) had significant deviation in SR of certain maternal age groups from the mean SR, but these deviations were not harmonized with joining age groups and thus were considered as a chance effect due to multiple testing. In conclusion, our study did not suggest that in general SR of isolated CAs might be modified by certain maternal age groups with some exception such as anencephaly and craniosynostosis.

  20. The Risser sign for forensic age estimation in living individuals: a study of 643 pelvic radiographs.

    PubMed

    Wittschieber, Daniel; Schmeling, Andreas; Schmidt, Sven; Heindel, Walter; Pfeiffer, Heidi; Vieth, Volker

    2013-03-01

    Due to increasing international migratory movements, forensic age estimations of living individuals in criminal proceedings are gaining increasing significance for forensic physicians and radiologists involved in delivering expert opinions. The present study examines the suitability of the radiologically well-known Risser sign grading as a possible new criterion in forensic age diagnostics. For this purpose, anteroposterior pelvic radiographs of 643 patients aged between 10 and 30 years were retrospectively evaluated by means of two different Risser sign grading systems (US and French), each with 5 stages. The left and right sides of the pelvis were assessed separately. The data was analyzed with separation of the sexes. Reliable Risser sign determination was possible in 566 cases. In both sexes, stage 4 of both the US and the French grading systems was predominantly first noted at age 14 years. In the US grading system, stage 5 was also first achieved at age 14 years in the majority of both sexes. In the French grading system, females manifested stage 5 at a minimum of 16 years, whereas in males it was first observed at 17 years. As to the nature of iliac crest maturation, interesting deviations were observed at stages 1 and 5, raising doubts about Risser's ossification process. To conclude, both Risser sign grading systems are suitable for forensic age diagnostics, especially to determine whether the 14th year of life has been completed or not. The French Risser sign system additionally allows for statements as to the completion of the 16th year of age.

  1. Axial Length, Anterior Chamber Depth-A Study in Different Age Groups and Refractive Errors

    PubMed Central

    Bhardwaj, Veena; Rajeshbhai, Gandhi Parth

    2013-01-01

    Introduction: Axial length and anterior chamber depth play an important role in refractive status of the eye in different age groups. Material and Methods: The present study has been done on 240 patients (480 eyes) who attended eye OPD of Department of Ophthalmology at NIMS Medical College & Hospital Jaipur, Rajasthan, India. The patients attending eye OPD between July 2011 to December 2012 of different ages groups were without significant history of any ocular disease. The axial length and anterior chamber depth were measured and compared. Conclusion: Hypermetropic eyes have shallow anterior chamber depth and shorter axial length as compared to myopic and emmtropic eyes. PMID:24298478

  2. Basic study of the portable fatigue meter: effects of illumination, distance from eyes and age.

    PubMed

    Hosokawa, T; Mikami, K; Saito, K

    1997-09-01

    Several aspects of a new, small and inexpensive fatigue assessment tool, the Portable Fatigue Meter (PFM), were studied. In the first experiment the effects of room illumination and distance between the PFM and the eyes on critical flicker fusion frequency (CFF) values were examined. The results revealed that the PFM CFF value varied significantly as a function of the distance between the indicator and the eyes, but it was not affected by room illumination. The effect of ageing on the PFM CFF value was assessed in a second experiment. The results suggested that PFM CFF values are significantly smaller in middle-aged females than in younger females.

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

    PubMed Central

    2011-01-01

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

  4. Cognitive and Psychosocial Consequences of Hurricanes Katrina and Rita Among Middle-Aged, Older, and Oldest-Old Adults in the Louisiana Healthy Aging Study (LHAS)1

    PubMed Central

    Cherry, Katie E.; Su, L. Joseph; Welsh, David A.; Galea, Sandro; Jazwinski, S. Michal; Silva, Jennifer L.; Erwin, Marla J.

    2010-01-01

    This study examined the impact of Hurricanes Katrina and Rita on cognitive and psychosocial functioning among middle-aged (45–64 years), older (65–89 years) and oldest-old adults (90 years and over) in the Louisiana Healthy Aging Study (LHAS). Analyses of pre- and post-disaster cognitive data showed storm-related decrements in working memory for the middle-aged and older adults, but not for the oldest-old adults. Regression analyses confirmed that measures of social engagement and storm-related disruption significantly predicted pre- to post-disaster differences in short-term and working memory performance for the middle-aged and older adults only. These results are consistent with a burden perspective on post-disaster psychological reactions. Implications for current views of disaster reactions are discussed. PMID:21461124

  5. Height and age adjustment for cross sectional studies of lung function in children aged 6-11 years.

    PubMed Central

    Chinn, S; Rona, R J

    1992-01-01

    BACKGROUND: No standard exists for the adjustment of lung function for height and age in children. Multiple regression should not be used on untransformed data because, for example, forced expiratory volume (FEV1), though normally distributed for height, age, and sex, has increasing standard deviation. A solution to the conflict is proposed. METHODS: Spirometry on representative samples of children aged 6.5 to 11.99 years in primary schools in England. After exclusion of children who did not provide two repeatable blows 910 white English boys and 722 girls had data on FEV1 and height. Means and standard deviations of FEV1 divided by height were plotted to determine whether logarithmic transformation of FEV1 was appropriate. Multiple regression was used to give predicted FEV1 for height and age on the transformed scale; back transformation gave predicted values in litres. Other lung function measures were analysed, and data on inner city children, children from ethnic minority groups, and Scottish children were described. RESULTS: After logarithmic (ln) transformation of FEV1 standard deviation was constant. The ratios of actual and predicted values of FEV1 were normally distributed in boys and girls. From the means and standard deviations of these distributions, and the predicted values, centiles and standard deviation scores can be calculated. CONCLUSION: The method described is valid because the assumption of stable variance for multiple regression was satisfied on the log scale and the variation of ratios of actual to predicted values on the original scale was well described by a normal distribution. The adoption of the method will lead to uniformity and greater ease of comparison of research findings. PMID:1440464

  6. [CERAD-NP battery: Age-, gender- and education-specific reference values for selected subtests. Results of the German Study on Ageing, Cognition and Dementia in Primary Care Patients (AgeCoDe)].

    PubMed

    Luck, T; Riedel-Heller, S G; Wiese, B; Stein, J; Weyerer, S; Werle, J; Kaduszkiewicz, H; Wagner, M; Mösch, E; Zimmermann, T; Maier, W; Bickel, H; van den Bussche, H; Jessen, F; Fuchs, A; Pentzek, M

    2009-10-01

    The CERAD-NP battery represents well-established tests for the neuropsychological diagnosis of characteristic cognitive deficits in Alzheimer's dementia. However, the use of neuropsychological tests requires reliable standard values for the population under consideration, taking sociodemographic characteristics like age, education and gender into account. This report presents age-, education- and gender-specific reference values for the subtests verbal fluency, word list memory, word list recall and word list recognition as well as the word list savings score of the CERAD-NP battery. The study sample consists of 2891 general practitioners' patients from Germany aged 75 years and older. The study participants had a mean age of 80.2 years (SD=3.6); thus, this report provides reliable reference values for the neuropsychological diagnosis of dementia in older age groups.

  7. Evidence for Cognitive Aging in Midlife Women: Study of Women’s Health Across the Nation

    PubMed Central

    Karlamangla, Arun S.; Lachman, Margie E.; Han, WeiJuan; Huang, MeiHua; Greendale, Gail A.

    2017-01-01

    Although cross-sectional studies suggest that cognitive aging starts in midlife, few longitudinal studies have documented within-individual declines in cognitive performance before the seventh decade. Learning from repeat testing, or practice effects, can mask the decline in younger cohorts. In women, the menopause transition also affects test performance and can confound estimates of underlying decline. We designed this study to determine if, after controlling for practice effects, the menopause transition, and the symptoms associated with it, there is evidence of cognitive aging in midlife women. We used data from a longitudinal observational study in 2,124 participants from the Study of Women’s Health Across the Nation. Outcomes examined were scores on annual tests of processing speed, verbal episodic memory (immediate and delayed), and working memory. To reduce the impact of practice effects and of the menopause transition, we used the third cognition testing visit as the baseline. Average age at this baseline was 54 years, and the majority of the women were postmenopausal; half the cohort was 2 or more years beyond the final menstrual period. There were 7,185 cognition assessments with median follow-up time of 6.5 years. In mixed effects regression, adjusted for practice effects, retention, menopause symtoms (depressive, anxiety, vasomotor, and sleep disturbance), and covariates, scores on 2 of 4 cognition tests declined. Mean decline in cognitive speed was 0.28 per year (95% confidence interval [CI] 0.20 to 0.36) or 4.9% in 10 years, and mean decline in verbal episodic memory (delayed testing) was 0.02 per year (95% CI: 0.00 to 0.03) or 2% in 10 years. Our results provide strong, longitudinal evidence of cognitive aging in midlife women, with substantial within-woman declines in processing speed and memory. Further research is needed to identify factors that influence decline rates and to develop interventions that slow cognitive aging. PMID:28045986

  8. State-of-the-art in longitudinal studies on aging: an overview of the supplement.

    PubMed

    Tappen, Ruth M; Ouslander, Joseph G

    2010-10-01

    The articles in this supplement are based on a conference held in January 2008 sponsored by a grant from the Robert Wood Johnson Foundation. The purpose of the conference was to summarize major findings and methodological issues in previous and ongoing longitudinal studies on aging and to identify potentially fruitful areas for future research. This article is a review and synthesis of the articles in this supplement. Each of the articles makes important contributions to summarizing existing research, identifying challenging methodological issues, or proposing areas that should be explored in future research. Three themes were identified: general improvement in the health status of the population aged 65 and older in the United States, a shift in longitudinal research on aging from a focus on the endpoints of disease to a focus on the preclinical stage and underlying mechanisms of these diseases, and contemporary developments in longitudinal research methodology. A number of practical suggestions were also drawn from the articles reviewed.

  9. Spectroscopic studies of the physical origin of environmental aging effects on doped graphene

    NASA Astrophysics Data System (ADS)

    Chang, J.-K.; Hsu, C.-C.; Liu, S.-Y.; Wu, C.-I.; Gharib, M.; Yeh, N.-C.

    2016-06-01

    The environmental aging effect of doped graphene is investigated as a function of the organic doping species, humidity, and the number of graphene layers adjacent to the dopant by studies of the Raman spectroscopy, x-ray and ultraviolet photoelectron spectroscopy, scanning electron microscopy, infrared spectroscopy, and electrical transport measurements. It is found that higher humidity and structural defects induce faster degradation in doped graphene. Detailed analysis of the spectroscopic data suggest that the physical origin of the aging effect is associated with the continuing reaction of H2O molecules with the hygroscopic organic dopants, which leads to formation of excess chemical bonds, reduction in the doped graphene carrier density, and proliferation of damages from the graphene grain boundaries. These environmental aging effects are further shown to be significantly mitigated by added graphene layers.

  10. Study of ageing and fading in CR-39 detectors for different storage conditions.

    PubMed

    Franci, Daniele; Aureli, Tommaso; Cardellini, Francesco

    2015-12-01

    The aim of this study was to investigate the effect of ageing and fading on PADC detector response, as a function of the storage time and temperature. Several groups of CR-39 detectors provided by Radosys, Ltd. were exposed at the reference radon chamber of the Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, at the ENEA centre in Casaccia. The results indicate that low-temperature storage inhibits the effect of both ageing and fading. Finally, the overall reduction in CR-39 sensitivity due to the combined ageing/fading effect was estimated. In particular, the sensitivity of the detectors continuously exposed in air at room temperature over 6 and 3 months was reduced, respectively, by 7.5 and 4 %.

  11. A field study on thermal comfort in an Italian hospital considering differences in gender and age.

    PubMed

    Del Ferraro, S; Iavicoli, S; Russo, S; Molinaro, V

    2015-09-01

    The hospital is a thermal environment where comfort must be calibrated by taking into account two different groups of people, that is, patients and medical staff. The study involves 30 patients and 19 medical staff with a view to verifying if Predicted Mean Vote (PMV) index can accurately predict thermal sensations of both groups also taking into account any potential effects of age and gender. The methodology adopted is based on the comparison between PMV values (calculated according to ISO 7730 after having collected environmental data and estimated personal parameters) and perceptual judgments (Actual Mean Vote, AMV), expressed by the subjects interviewed. Different statistical analyses show that PMV model finds his best correlation with AMV values in a sample of male medical staff under 65 years of age. It has been observed that gender and age are factors that must be taken into account in the assessment of thermal comfort in the hospital due to very weak correlation between AMV and PMV values.

  12. Candidate Gene Association Study of BMI-Related Loci, Weight, and Adiposity in Old Age

    PubMed Central

    2013-01-01

    Most genome-wide association studies are confined to middle-aged populations. It is unclear whether associations between single nucleotide polymorphisms (SNPs) and obesity persist in old age. We aimed to relate 10 body mass index (BMI)–associated SNPs to weight, BMI, % fat, visceral and subcutaneous adipose tissue in Health ABC and AGES-Reykjavik comprising 4,846 individuals of European Ancestry, and 1,139 African Americans over age 65. SNPs were scaled using effect estimates from candidate SNPs. In Health ABC, a SNP near GNPDA2 was modestly associated with weight and SAT area (p = .008, p = .001). Risk score (sum of scaled SNPs) was associated with weight, BMI, and SAT area (p < .0001 for all), but neither GNPDA2 nor risk score was associated with weight, BMI, visceral adippose tissue, subcutaneous adipose tissue, or % fat in AGES-Reykjavik. In African Americans, a SNP near SEC16B was weakly associated with weight (p = .04). In this sample of older adults, no BMI-associated SNPs were associated with weight or adiposity. PMID:23160366

  13. 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

  14. A genome scan for modifiers of age at onset in Huntington disease: The HD MAPS study.

    PubMed

    Li, Jian-Liang; Hayden, Michael R; Almqvist, Elisabeth W; Brinkman, Ryan R; Durr, Alexandra; Dodé, Catherine; Morrison, Patrick J; Suchowersky, Oksana; Ross, Christopher A; Margolis, Russell L; Rosenblatt, Adam; Gómez-Tortosa, Estrella; Cabrero, David Mayo; Novelletto, Andrea; Frontali, Marina; Nance, Martha; Trent, Ronald J A; McCusker, Elizabeth; Jones, Randi; Paulsen, Jane S; Harrison, Madeline; Zanko, Andrea; Abramson, Ruth K; Russ, Ana L; Knowlton, Beth; Djoussé, Luc; Mysore, Jayalakshmi S; Tariot, Suzanne; Gusella, Michael F; Wheeler, Vanessa C; Atwood, Larry D; Cupples, L Adrienne; Saint-Hilaire, Marie; Cha, Jang-Ho J; Hersch, Steven M; Koroshetz, Walter J; Gusella, James F; MacDonald, Marcy E; Myers, Richard H

    2003-09-01

    Huntington disease (HD) is caused by the expansion of a CAG repeat within the coding region of a novel gene on 4p16.3. Although the variation in age at onset is partly explained by the size of the expanded repeat, the unexplained variation in age at onset is strongly heritable (h2=0.56), which suggests that other genes modify the age at onset of HD. To identify these modifier loci, we performed a 10-cM density genomewide scan in 629 affected sibling pairs (295 pedigrees and 695 individuals), using ages at onset adjusted for the expanded and normal CAG repeat sizes. Because all those studied were HD affected, estimates of allele sharing identical by descent at and around the HD locus were adjusted by a positionally weighted method to correct for the increased allele sharing at 4p. Suggestive evidence for linkage was found at 4p16 (LOD=1.93), 6p21-23 (LOD=2.29), and 6q24-26 (LOD=2.28), which may be useful for investigation of genes that modify age at onset of HD.

  15. A Genome Scan for Modifiers of Age at Onset in Huntington Disease: The HD MAPS Study

    PubMed Central

    Li, Jian-Liang; Hayden, Michael R.; Almqvist, Elisabeth W.; Brinkman, Ryan R.; Durr, Alexandra; Dodé, Catherine; Morrison, Patrick J.; Suchowersky, Oksana; Ross, Christopher A.; Margolis, Russell L.; Rosenblatt, Adam; Gómez-Tortosa, Estrella; Cabrero, David Mayo; Novelletto, Andrea; Frontali, Marina; Nance, Martha; Trent, Ronald J. A.; McCusker, Elizabeth; Jones, Randi; Paulsen, Jane S.; Harrison, Madeline; Zanko, Andrea; Abramson, Ruth K.; Russ, Ana L.; Knowlton, Beth; Djoussé, Luc; Mysore, Jayalakshmi S.; Tariot, Suzanne; Gusella, Michael F.; Wheeler, Vanessa C.; Atwood, Larry D.; Cupples, L. Adrienne; Saint-Hilaire, Marie; Cha, Jang-Ho J.; Hersch, Steven M.; Koroshetz, Walter J.; Gusella, James F.; MacDonald, Marcy E.; Myers, Richard H.

    2003-01-01

    Huntington disease (HD) is caused by the expansion of a CAG repeat within the coding region of a novel gene on 4p16.3. Although the variation in age at onset is partly explained by the size of the expanded repeat, the unexplained variation in age at onset is strongly heritable (h2=0.56), which suggests that other genes modify the age at onset of HD. To identify these modifier loci, we performed a 10-cM density genomewide scan in 629 affected sibling pairs (295 pedigrees and 695 individuals), using ages at onset adjusted for the expanded and normal CAG repeat sizes. Because all those studied were HD affected, estimates of allele sharing identical by descent at and around the HD locus were adjusted by a positionally weighted method to correct for the increased allele sharing at 4p. Suggestive evidence for linkage was found at 4p16 (LOD=1.93), 6p21–23 (LOD=2.29), and 6q24–26 (LOD=2.28), which may be useful for investigation of genes that modify age at onset of HD. PMID:12900792

  16. Intake of melatonin increases tryptophan hydroxylase type 1 activity in aged rats: Preliminary study.

    PubMed

    Moranta, D; Barceló, P; Aparicio, S; Garau, C; Sarubbo, F; Ramis, M; Nicolau, C; Esteban, S

    2014-01-01

    Pineal melatonin is important not only for synchronization of biological rhythms, but also in the ageing process as a potential drug to relieve oxidative damage. During ageing, the nocturnal melatonin production decreases resulting in an increased incidence of disorders. Present in vivo experiments were performed to study the effects of exogenous melatonin chronically administered to old rats on the pineal biosynthesis of melatonin and the precursor serotonin (5-HT) mediated by tryptophan hydroxylase type 1 (TPH-1). Accumulation of 5-hydroxytryptophan (5-HTP) after decarboxylase inhibition was used as a measure of the TPH-1 activity. 5-HT and its metabolite 5-HIAA were also quantified by HPLC-ED. As expected, ageing resulted in worsening of different neurochemical parameters. However, chronic intake of melatonin (1mg/kg/day, diluted in drinking water, 4 weeks) increased TPH-1 activity and significantly improved the age-induced deficits in nocturnal melatonin content in the pineal gland. Results suggest that melatonin intake (or melatonin rich foods) may contribute to recover the pineal function preventing the nocturnal descent of 5-HT and melatonin biosynthesis that normally occur in pineal gland as a consequence of ageing.

  17. AGE AT ONSET TYPOLOGY IN OPIOID DEPENDENT MEN: AN EXPLORATORY STUDY

    PubMed Central

    De, Biswajit; Mattoo, Surendra K.; Basu, Debasish

    2002-01-01

    This study attempted to apply age at onset typology in ICD-10 diagnosed opioid dependence. The sample comprised 80 men seeking treatment at an addiction clinic. The measures included socio-demographic and clinical profile, Severity of Opioid Dependence Questionnaire, Modified Sensation Seeking Scale, Multiphasic Personality Questionnaire (MPQ) and Family History Assessment Module. A cut-off age of 20/21 years for an early-onset late-onset typology of opioid dependence was obtained using two methods - the modal age at onset method and one-third sample by age at onset method. The early onset group showed significant differences in terms of it being more often younger, urban, unmarried, wage earning or students, using oral opioids (not heroin or injectables), showing higher lifetime use and dependence of sedatives, earlier onset of use and dependence of sedatives and tobacco, and higher global psychopathology in terms of MPQ. The early onset group also showed statistically insignificant trends for lesser use and dependence of alcohol, higher severity of opioid dependence, more legal and less social complications, higher sensation seeking (except boredom susceptibility), and more frequent substance dependence in first degree relatives. The age at onset typology in opioid dependence appears to be feasible and having some similarities to similar typology in alcoholism. PMID:21206561

  18. Ageing, genes, environment and epigenetics: what twin studies tell us now, and in the future.

    PubMed

    Steves, Claire Joanne; Spector, Timothy D; Jackson, Stephen H D

    2012-09-01

    Compared with younger people, older people are much more variable in their organ function, and these large individual differences contribute to the complexity of geriatric medicine. What determines this variability? Is it due to the accumulation of different life experiences, or because of the variation in the genes we are born with, or an interaction of both? This paper reviews key findings from ageing twin cohorts probing these questions. Twin studies are the perfect natural experiment to dissect out genes and life experiences. We discuss the paradox that ageing is strongly determined by heritable factors (an influence that often gets stronger with time), yet longevity and lifespan seem not to be so heritable. We then focus on the intriguing question of why DNA sequence-identical twins might age differently. Animal studies are increasingly showing that epigenetic modifications occurring in early development and adulthood, might be key to ageing phenomena but this is difficult to investigate longitudinally in human populations, due to ethical problems of intervention and long lifespan. We propose that identical twin studies using new and existing cohorts may be useful human models in which to investigate the interaction between the environment and genetics, mediated by epigenetic modifications.

  19. Personality Traits and Successful Aging: Findings From the Georgia Centenarian Study.

    PubMed

    Baek, Yousun; Martin, Peter; Siegler, Ilene C; Davey, Adam; Poon, Leonard W

    2016-09-01

    The current study attempted to describe how personality traits of older adults are associated with components of successful aging (cognition, volunteering, activities of daily living, and subjective health). Three-hundred and six octogenarians and centenarians who participated in the third phase of the Georgia Centenarian Study provided data for this study. Factor analysis was conducted to test the existence of two higher-order factors of the Big Five personality traits, and a two-factor model (alpha and beta) fit the data well. Also, blocked multiple regression analysis was conducted to examine the association between personality traits and four components of successful aging. Results indicated that low scores on neuroticism and high scores on extraversion, openness to experience, agreeableness, and conscientiousness are significantly related to the components of successful aging. After controlling for demographic variables (age, gender, residential type, and race/ethnicity), alpha (i.e., emotional stability, agreeableness, and conscientiousness) was associated with higher levels of cognition, higher likelihood of engaging in volunteer work, higher levels of activities of daily living, and higher levels of subjective health. Beta (i.e., extraversion and openness to experience) was also positively associated with cognition and engaging in volunteer work.

  20. 3D-printed microfluidic microdissector for high-throughput studies of cellular aging.

    PubMed

    Spivey, Eric C; Xhemalce, Blerta; Shear, Jason B; Finkelstein, Ilya J

    2014-08-05

    Due to their short lifespan, rapid division, and ease of genetic manipulation, yeasts are popular model organisms for studying aging in actively dividing cells. To study replicative aging over many cell divisions, individual cells must be continuously separated from their progeny via a laborious manual microdissection procedure. Microfluidics-based soft-lithography devices have recently been used to automate microdissection of the budding yeast Saccharomyces cerevisiae. However, little is known about replicative aging in Schizosaccharomyces pombe, a rod-shaped yeast that divides by binary fission and shares many conserved biological functions with higher eukaryotes. In this report, we develop a versatile multiphoton lithography method that enables rapid fabrication of three-dimensional master structures for polydimethylsiloxane (PDMS)-based microfluidics. We exploit the rapid prototyping capabilities of multiphoton lithography to create and characterize a cell-capture device that is capable of high-resolution microscopic observation of hundreds of individual S. pombe cells. By continuously removing the progeny cells, we demonstrate that cell growth and protein aggregation can be tracked in individual cells for over ~100 h. Thus, the fission yeast lifespan microdissector (FYLM) provides a powerful on-chip microdissection platform that will enable high-throughput studies of aging in rod-shaped cells.

  1. A study of Lycium barbarum polysaccharides (LBP) extraction technology and its anti-aging effect.

    PubMed

    Yi, Ran; Liu, Xiao-Min; Dong, Qi

    2013-01-01

    The objective of the study was to optimise the LBP extraction technology and to study the anti-aging effect of LBP by establishing D-gal aging mouse model. Orthogonal design was used to study the extraction technology. The experimental aging mouse model was formed by continuous injection of D-gal, and the anti-aging capacity of LBP was tested using measuring MDA, CAT and GSH-px contents and SOD activity in blood and SOD, MDA and Hyp levels in skin. The results showed that the optimum LBP extraction option determined by the orthogonal design is as follows: solid-liquid ratio of 1:30, extraction for 2 times, 90 min each time, and power is 100 kHz. Thus, LBP can increase SOD, CAT and GSH-px levels in blood and reduce MDA level. It can also improve skin SOD activity, reduce skin MDA content, and increase Hyp content. We concluded that the extraction method established in this experiment is easy and feasible, and the yield of LBP is high, apparently showing that LBP has the potential of delaying senility in D-gal induced mice.

  2. Malocclusions in children at 3 and 7 years of age: a longitudinal study.

    PubMed

    Dimberg, Lillemor; Lennartsson, Bertil; Söderfeldt, Björn; Bondemark, Lars

    2013-02-01

    The aim of this longitudinal study was to compare the prevalence of malocclusion at ages 3 and 7 years in a sample of children, exploring the hypothesis that prevalence of malocclusion is higher at 3 than at 7 years of age and may be influenced by sucking habits. The study sample comprised 386 children (199 girls and 187 boys), aged 3 years at study start, sourced from three Public Dental Service clinics in Sweden. Malocclusion was diagnosed by clinical examination, using a specific protocol. Data on allergy, traumatic injuries, sucking habits, and breathing pattern including nocturnal breathing disturbances were obtained by means of a questionnaire answered by child and parent in conjunction with the initial and final clinical examination. The overall prevalence of malocclusion decreased significantly, from 70 to 58% (P < 0.0001): predominantly anterior open bite, excessive overjet, and Class III malocclusion. Although high rates of spontaneous correction were also noted for deep bite, Class II malocclusion and posterior and anterior crossbites, new cases developed at almost the same rate; thus, the prevalence was unchanged at the end of the observation period. Anterior open bite and posterior crossbite were the only conditions showing significant associations with sucking habits. The results confirm the hypothesis of higher prevalence of malocclusion at 3 years of age and clearly support the strategy of deferring orthodontic correction of malocclusion until the mixed dentition stage.

  3. A two decade dementia incidence comparison from the Cognitive Function and Ageing Studies I and II

    PubMed Central

    Matthews, F. E.; Stephan, B. C. M.; Robinson, L.; Jagger, C.; Barnes, L. E.; Arthur, A.; Brayne, C.; Comas-Herrera, A.; Wittenberg, R.; Dening, T.; McCracken, C.F.M.; Moody, C.; Parry, B.; Green, E.; Barnes, R.; Warwick, J.; Gao, L.; Mattison, A.; Baldwin, C.; Harrison, S.; Woods, B.; McKeith, I.G.; Ince, P.G.; Wharton, S.B.; Forster, G.

    2016-01-01

    Dramatic global increases in future numbers of people with dementia have been predicted. No multicentre population-based study powered to detect changes over time has reported dementia incidence. MRC Cognitive Function and Ageing Study (CFAS) undertook baseline interviews in populations aged 65+ years in England and Wales (1989–1994). Three areas (CFAS I) were selected for new sampling two decades later (2008–2011) with same geographical boundaries, sampling and approach methods (CFAS II). At 2 years CFAS I interviewed 5,156 (76% response) with 5,288 interviewed in CFAS II (74% response). Here we report a 20% drop in incidence (95% CI: 0–40%), driven by a reduction in men across all ages above 65. In the UK we estimate 209,600 new dementia cases per year. This study was uniquely designed to test for differences across geography and time. A reduction of age-specific incidence means that the numbers of people estimated to develop dementia in any year has remained relatively stable. PMID:27092707

  4. 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

  5. Ubiquity and diversity of heterotrophic bacterial nasA genes in diverse marine environments.

    PubMed

    Jiang, Xuexia; Dang, Hongyue; Jiao, Nianzhi

    2015-01-01

    Nitrate uptake by heterotrophic bacteria plays an important role in marine N cycling. However, few studies have investigated the diversity of environmental nitrate assimilating bacteria (NAB). In this study, the diversity and biogeographical distribution of NAB in several global oceans and particularly in the western Pacific marginal seas were investigated using both cultivation and culture-independent molecular approaches. Phylogenetic analyses based on 16S rRNA and nasA (encoding the large subunit of the assimilatory nitrate reductase) gene sequences indicated that the cultivable NAB in South China Sea belonged to the α-Proteobacteria, γ-Proteobacteria and CFB (Cytophaga-Flavobacteria-Bacteroides) bacterial groups. In all the environmental samples of the present study, α-Proteobacteria, γ-Proteobacteria and Bacteroidetes were found to be the dominant nasA-harboring bacteria. Almost all of the α-Proteobacteria OTUs were classified into three Roseobacter-like groups (I to III). Clone library analysis revealed previously underestimated nasA diversity; e.g. the nasA gene sequences affiliated with β-Proteobacteria, ε-Proteobacteria and Lentisphaerae were observed in the field investigation for the first time, to the best of our knowledge. The geographical and vertical distributions of seawater nasA-harboring bacteria indicated that NAB were highly diverse and ubiquitously distributed in the studied marginal seas and world oceans. Niche adaptation and separation and/or limited dispersal might mediate the NAB composition and community structure in different water bodies. In the shallow-water Kueishantao hydrothermal vent environment, chemolithoautotrophic sulfur-oxidizing bacteria were the primary NAB, indicating a unique nitrate-assimilating community in this extreme environment. In the coastal water of the East China Sea, the relative abundance of Alteromonas and Roseobacter-like nasA gene sequences responded closely to algal blooms, indicating that NAB may be

  6. The Effect of Donor Age on Corneal Transplantation Outcome: Results of the Cornea Donor Study

    PubMed Central

    2009-01-01

    patients now have evidence that corneas comparable in quality to those used in this study from donors through age 75 years are suitable for transplantation. PMID:18387407

  7. NAS Parallel Benchmark Results 11-96. 1.0

    NASA Technical Reports Server (NTRS)

    Bailey, David H.; Bailey, David; Chancellor, Marisa K. (Technical Monitor)

    1997-01-01

    The NAS Parallel Benchmarks have been developed at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a "pencil and paper" fashion. In other words, the complete details of the problem to be solved are given in a technical document, and except for a few restrictions, benchmarkers are free to select the language constructs and implementation techniques best suited for a particular system. These results represent the best results that have been reported to us by the vendors for the specific 3 systems listed. In this report, we present new NPB (Version 1.0) performance results for the following systems: DEC Alpha Server 8400 5/440, Fujitsu VPP Series (VX, VPP300, and VPP700), HP/Convex Exemplar SPP2000, IBM RS/6000 SP P2SC node (120 MHz), NEC SX-4/32, SGI/CRAY T3E, SGI Origin200, and SGI Origin2000. We also report High Performance Fortran (HPF) based NPB results for IBM SP2 Wide Nodes, HP/Convex Exemplar SPP2000, and SGI/CRAY T3D. These results have been submitted by Applied Parallel Research (APR) and Portland Group Inc. (PGI). We also present sustained performance per dollar for Class B LU, SP and BT benchmarks.

  8. Age, education and dementia related deaths. The Norwegian Counties Study and The Cohort of Norway.

    PubMed

    Strand, Bjørn Heine; Langballe, Ellen Melbye; Rosness, Tor A; Bergem, Astrid Liv Mina; Engedal, Knut; Nafstad, Per; Tell, Grethe S; Ormstad, Heidi; Tambs, Kristian; Bjertness, Espen

    2014-10-15

    An inverse relationship between educational level and dementia has been reported in several studies. In this study we investigated the relationship between educational level and dementia related deaths for cohorts of people all born during 1915-39. The cohorts were followed up from adulthood or old age, taking into account possible confounders and mediating paths. Our study population comprised participants in Norwegian health examination studies in the period 1974-2002; The Counties Study and Cohort of Norway (CONOR). Dementia related deaths were defined as deaths with a dementia diagnosis on the death certificate and linked using the Cause of Death Registry to year 2012. The study included 90,843 participants, 2.06 million person years and 2440 dementia related deaths. Cox regression was used to assess the association between education and dementia related deaths. Both high and middle educational levels were associated with lower dementia related death risk compared to those with low education when follow-up started in adulthood (35-49 years, high versus low education: HR=0.68, 95% confidence interval (CI) 0.50-0.93; 50-69 years, high versus low education: HR=0.52, 95% CI 0.34-0.80). However, when follow-up started at old age (70-80 years) there was no significant association between education and dementia related death. Restricting the study population to those born during a five-year period 1925-29 (the birth cohort overlapping all three age groups), gave similar main findings. The protective effects found for both high and middle educational level compared to low education were robust to adjustment for cardiovascular health and life style factors, suggesting education to be a protective factor for dementia related death. Both high and middle educational levels were associated with decreased dementia related death risk compared with low educational level when follow-up started in adulthood, but no association was observed when follow-up started at old age.

  9. RECENT DEVELOPMENTS IN LONGITUDINAL STUDIES OF AGING IN THE UNITED STATES*

    PubMed Central

    WEIR, DAVID

    2015-01-01

    We review recent developments in longitudinal studies of aging, focusing on the Wisconsin Longitudinal Study (WLS) and the Health and Retirement Study (HRS). Both studies are part of a trend toward biosocial surveys in which biological measurement is joined with traditional survey techniques, and a related trend toward greater harmonization across studies. Both studies have collected DNA samples and are working toward genotyping that would allow broadly based association studies. Increased attention to psychological measurement of personality and of cognitive ability using adaptive testing structures has also been shared across the studies. The HRS has expanded its economic measurement to longitudinal studies of consumption and to broader-based measurement of pension and Social Security wealth. It has added biomarkers of cardiovascular risk. The WLS has developed an integrated approach to the study of death and bereavement and an innovative use of high school yearbook photographs to capture information about health in early life of its participants. PMID:21302430

  10. Brain aging in normal Egyptians: cognition, education, personality, genetic and immunological study.

    PubMed

    Elwan, Osamah; Madkour, Obsis; Elwan, Fadia; Mostafa, Mervat; Abbas Helmy, Azza; Abdel-Naseer, Maged; Abdel Shafy, Sanaa; El Faiuomy, Nervana

    2003-07-15

    Studying the cognitive and immunological changes that occur in old age as well as genetic function have been considered an important subject to differentiate between normal brain aging and early dementia especially Alzheimer's disease. The aim of this study is to stress on age-related neuropsychological and electrophysiological (P(300)) changes in normal Egyptian subjects, to throw light on the value of genetic (Apo-E(4) genotype) and immunological markers [interleukin-6 (IL-6) and intercellular adhesion molecules (ICAM-1) in the serum] as tools used in early detection of cognitive decline in cerebral aging. Ninety-four normal Egyptian subjects (below and above 60 years) were submitted to the following: (1) neuropsychological tests for testing memory, perception, psychomotor performance and attention, (2) Eysenck Personality Questionnaire (EPQ) for personality traits, (3) event-related potential study (P(300), latency and amplitude), (4) genetic test for detection of Apolipoprotein E genotype and (5) immunological studies including detection of the level of IL-6 and ICAM-1 in serum. There was a significant impairment of memory, psychomotor performance and perception in elderly subjects particularly males and subjects with low level of education. Regarding personality, significantly high scores were obtained in neuroticism scale of EPQ in elderly subjects. Apo-E(3)/E(3) was the most common genotype encountered in Egyptian subjects (49.1%). It was found that subjects with Apo-E(4) genotype did significantly worse in scores of intentional memory test (sensory memory) when compared with other genotypes. Statistically significant impairment in attention and sensory memory was found in subjects with high IL-6 level. This could not be detected in subjects with high ICAM-1 level. In conclusion, advancing age and lower levels of education are considered risk factors for cognitive decline in normal brain aging. Neuropsychological tests remain as the highly sensitive tools

  11. Supercritical fractions as asphalt recycling agents and preliminary aging studies on recycled asphalts

    SciTech Connect

    Chaffin, J.M.; Liu, M.; Davison, R.R.; Glover, C.J.; Bullin, J.A.

    1997-03-01

    Several asphalts were fractionated using supercritical pentane. These fractions were analyzed by gel permeation chromatography and high-performance liquid chromatography, and their viscosities were measured. The properties of these fractions vary not only among the fractions of a given asphalt but also for the same fraction produced from different asphalts. These widely varied fractions previously have been shown to have potential for reblending to produce superior asphalts. This study investigates the potential for using some of the fractions as asphalt recycling agents. A modified strategic highway research program (SHRP) pressure aging vessel (PAV) test and kinetics studies were conducted on nine recycled asphalts and the original asphalt. The aging indexes of eight of the recycled asphalts are superior to the aging index of the original asphalt. Two of the blends using industrial supercritical fractions and the three blends using laboratory supercritical fractions have lower aging indexes than blends using commercial recycling agents. The kinetics investigation also indicates that at road conditions the recycled asphalts will harden more slowly than the original asphalt. The degree of hardening for a given amount of oxidation in the recycled binders was found to be a strong function of the total saturate content in the recycled binder.

  12. Ups and downs of aging studies in vitro: the crooked path of science.

    PubMed

    Macieira-Coelho, A

    2000-01-01

    Different approaches using cell culture techniques to study the biology of aging are critically described. Most of the studies concerned the relationship between cell division potential and aging. The growth potential of cells is fundamental for aging of the organism, since it relates to phenomena such as the regeneration of tissues, wound healing, the immune response, and stem cell renewal. Unfortunately many experiments were misinterpreted disregarding the physiology of the mammalian organism. The terminal postmitotic cell, on which most research has been concentrated, seems irrelevant for aging of the organism. Nevertheless, some experiments yielded important contributions to the understanding of the biology of cell division. Future research should ascertain such interesting suggestions as the terminal differentiation hypothesis of the human fibroblast life cycle. It is important to elucidate the significance of the increased number of postmitotic cells in pathological processes. A neglected area should be further explored: the relationships between structural modifications of the cell, decreased probability of activating energy barriers, and decline of the division potential.

  13. [Comparative study of height and age at menarche according to the socioeconomic level in Venezuela].

    PubMed

    López Contreras, M; Tovar Escobar, G; Farid Coupal, N; Landaeta Jiménez, M; Méndez Castellano, H

    1981-12-01

    This is a retrospective study based on growth and development data published in Venezuela by various authors in the period 1936-1978. The data on height for males of the middle and high socioeconomic strata show growth curves which are very similar to the standards for British children. Likewise, the girls of the same socioeconomic condition follow the British standards, but only up to about 10-12 years of age. After that age, the girls studied by the Venezuelan authors, show a pattern of early maturation with a corresponding lower adult height compared with their British counterparts. There were differences in the growth curves according to the socioeconomic strata. These differences were more marked in the girls data. A secular increase for height was discerned, from the published data, in all socioeconomic strata and in both sexes. The data on sexual maturation showed a tendency for progressively early menarche in Venezuelan girls. These changes in growth in height and age of menarche were more notorious and came about at an earlier age in the upper socioeconomic strata. They were less marked, not constant, and came about later in the lower socioeconomic groups. The secular changes in height and sexual maturation apparent from these data, could be explained by an improvement in the environmental conditions, especially nutrition and hygiene of the population, and also be genetic heterosis from European immigration and with improvement in communications.

  14. Age-Related Changes in Nucleus Pulposus Mesenchymal Stem Cells: An In Vitro Study in Rats

    PubMed Central

    Lin, Linghan

    2017-01-01

    The functions of mesenchymal stem cells (MSCs) appear to decline with age due to cellular senescence, which could reduce the efficacy of MSCs-based therapies. Recently, MSCs have been identified in the nucleus pulposus, which offers great potential for intervertebral disc (IVD) repair. However, this potential might be affected by the senescence of nucleus pulposus MSCs (NPMSCs), but whether or not this exists remains unknown. The aim of this study was to investigate the age-related changes in NPMSCs. NPMSCs isolated from young (3-month-old) and old (14-month-old) Sprague-Dawley rats were cultured in vitro. Differences in morphology, proliferation, colony formation, multilineage differentiation, cell cycle, and expression of β-galactosidase (SA-β-gal) and senescent markers (p53, p21, and p16) were compared between groups. Both young and old NPMSCs fulfilled the criteria for definition as MSCs. Moreover, young NPMSCs presented better proliferation, colony-forming, and multilineage differentiation capacities than old NPMSCs. Old NPMSCs displayed senescent features, including significantly increased G0/G1 phase arrest, increased SA-β-gal expression, decreased S phase entry, and significant p53-p21-pRB pathway activation. Therefore, this is the first study demonstrating that senescent NPMSCs accumulate in IVD with age. The efficacy of NPMSCs is compromised by donor age, which should be taken into consideration prior to clinical application.

  15. Correlates of cognitive function in middle-aged adults. Atherosclerosis Risk in Communities (ARIC) Study Investigators.

    PubMed

    Cerhan, J R; Folsom, A R; Mortimer, J A; Shahar, E; Knopman, D S; McGovern, P G; Hays, M A; Crum, L D; Heiss, G

    1998-01-01

    The Atherosclerosis Risk in Communities Study administered cognitive function tests to more than 14,000 middle-aged adults in 1990-1992. The battery included the Delayed Word Recall test, the Digit Symbol Subtest of the Wechsler Adult Intelligence Scale-Revised, and the Controlled Oral Word Association (Word Fluency) test. Test performance was correlated positively with education level, negatively with age, was better in women than in men, and better in managers/professionals compared with other occupations. After controlling for these factors, race and community, the findings most consistent for both sexes were that Delayed Word Recall was negatively associated with depressive symptoms, diabetes, and fibrinogen level; the Digit Symbol Subtest was associated with marital status, negatively associated with depressive symptoms, smoking status, fibrinogen level, and carotid intima-media thickness, and positively associated with alcohol drinking and FEV1; and the Word Fluency test was positively associated with marital status, alcohol drinking, sports participation, and FEV1. Most of these cross-sectional results were in the predicted direction and have biologic plausibility, but mean differences between extreme categories were small (generally on the order of 0.1 to 0.2 of a standard deviation). Longitudinal study is warranted to evaluate whether small differences in middle-age lead to larger, clinically meaningful deficits with aging.

  16. Changing channels: an fMRI study of aging and cross-modal attention shifts.

    PubMed

    Townsend, Jeanne; Adamo, Maha; Haist, Frank

    2006-07-15

    Age-related deficits in visual selective attention suggest that the efficiency of inhibitory processes is particularly affected by aging. To investigate whether processing inefficiencies observed in visual attention are similar in auditory attention and when shifting attention across modalities, we conducted an fMRI study with healthy young and older adults using a task that required sustained auditory and visual selective attention and cross-modal attention shifts. Older adults in this study performed as well as the younger adults, but showed age-related differences in BOLD responses. The most striking of these differences were bilateral frontal and parietal regions of significantly increased activation in older adults during both focused and shifting attention. Our data suggest that this increased activation did not reflect new recruitment, but reliance on brain regions typically used by younger adults when task demands are greater. Older adults' activation patterns suggested that even during focused attention conditions they were "shifting" attention to stimuli in the unattended modality. Increased activation during processing of both task-relevant and task-irrelevant information implies age-related loss of processing selectivity. These patterns may reflect both task-specific compensatory neural recruitment and degradation of sensory inhibition.

  17. Just change the channel? Studying effects of age on emotion regulation using a TV watching paradigm.

    PubMed

    Sands, Molly; Garbacz, Adam; Isaacowitz, Derek M

    2016-11-01

    Older adults are theorized to benefit from proactive forms of emotion regulation that allow them to avoid negative stimuli (Charles, 2010). To test this, we examined choices as a form of emotion regulation. In two studies investigating age differences, participants selected affective stimuli using a cable television interface, while choices and mood were recorded. In lab-based Study 1, older adults spent more time watching neutral channels, but younger adults spent more time watching positive ones. Older adults also watched more low-arousal content, while younger adults watched more high-arousal content. Lagged analyses revealed that younger adults' choices were directed toward increasing positive affect and arousal. Study 2 replicated these findings in a community-based adult lifespan sample at a local museum. These findings suggest that arousal plays an important role in motivating emotion regulation behavior in the context of selections, and this differs by age.

  18. A Study on the Age-Related Changes in Hepatitis B and C Virus Serology

    PubMed Central

    Guclu, Ertugrul; Ogutlu, Aziz; Karabay, Oguz

    2016-01-01

    Objective: There are a limited number of studies on the seroprevalence of Hepatitis B virus (HBV) and Hepatitis C virus (HCV) infection in Turkey. This study aimed to compare HBV and HCV seroprevalence rates before and after the implementation of national hepatitis B vaccination program (NHPVP) and to explore age-related changes in the seroprevalences. Materials and Methods: Results of Hepatitis B surface antigen (HBsAg), Hepatitis B virus surface antibody (antiHBs) and anti-HCV tests performed during 2009 and 2010 in a state hospital laboratory were reviewed retrospectively. As NHPVP was started in 1998, 12 years of age and younger children were considered post- NHPVP period subjects. Results: A total of 3280 HBsAg, 2444 antiHBs and 3188 anti-HCV test results were reviewed, representing approximately 3% of the population of the city where the study was conducted. HBsAg, antiHBs and anti-HCV positivity were 3.2%, 36.12% and 0.97%, respectively. HBsAg and antiHBs positivity were higher among males (p<0.001). When assessed by age groups, HBsAg positivity was found to be the lowest in the age group 0–12 and highest in the age group 51–60. HBsAg positivity was lower in the post-NHPVP period versus pre-NHPVP period (p=0.01). Anti-HCV positivity was similar for pre- and post- NHPVP periods (p>0.05). Conclusion: Owing to the use of NHPVP, HBsAg seropositivity has decreased, and it is expected to decrease further in the next years with a wider implementation of the program. Efforts should be continued to increase the level of awareness in the community for HBV and the importance of immunization. PMID:27026763

  19. Low heel ultrasound parameters predict mortality in men: results from the European Male Ageing Study (EMAS)

    PubMed Central

    Pye, Stephen R.; Vanderschueren, Dirk; Boonen, Steven; Gielen, Evelien; Adams, Judith E.; Ward, Kate A.; Lee, David M.; Bartfai, György; Casanueva, Felipe F.; Finn, Joseph D.; Forti, Gianni; Giwercman, Aleksander; Han, Thang S.; Huhtaniemi, Ilpo T.; Kula, Krzysztof; Lean, Michael E.; Pendleton, Neil; Punab, Margus; Wu, Frederick C.; O'Neill, Terence W.

    2015-01-01

    Background: low bone mineral density measured by dual-energy x-ray absorptiometry is associated with increased mortality. The relationship between other skeletal phenotypes and mortality is unclear. The aim of this study was to determine the relationship between quantitative heel ultrasound parameters and mortality in a cohort of European men. Methods: men aged 40–79 years were recruited for participation in a prospective study of male ageing: the European Male Ageing Study (EMAS). At baseline, subjects attended for quantitative ultrasound (QUS) of the heel (Hologic—SAHARA) and completed questionnaires on lifestyle factors and co-morbidities. Height and weight were measured. After a median of 4.3 years, subjects were invited to attend a follow-up assessment, and reasons for non-participation, including death, were recorded. The relationship between QUS parameters (broadband ultrasound attenuation [BUA] and speed of sound [SOS]) and mortality was assessed using Cox proportional hazards model. Results: from a total of 3,244 men (mean age 59.8, standard deviation [SD] 10.8 years), 185 (5.7%) died during the follow-up period. After adjusting for age, centre, body mass index, physical activity, current smoking, number of co-morbidities and general health, each SD decrease in BUA was associated with a 20% higher risk of mortality (hazard ratio [HR] per SD = 1.2; 95% confidence interval [CI] = 1.0–1.4). Compared with those in higher quintiles (2nd–5th), those in the lowest quintile of BUA and SOS had a greater mortality risk (BUA: HR = 1.6; 95% CI = 1.1–2.3 and SOS: HR = 1.6; 95% CI = 1.2–2.2). Conclusion: lower heel ultrasound parameters are associated with increased mortality in European men. PMID:26162912

  20. Incidence of Dementia Among Participants and Nonparticipants in a Longitudinal Study of Cognitive Aging

    PubMed Central

    Knopman, David S.; Roberts, Rosebud O.; Pankratz, V. Shane; Cha, Ruth H.; Rocca, Walter A.; Mielke, Michelle M.; Boeve, Bradley F.; Tangalos, Eric G.; Ivnik, Robert J.; Geda, Yonas E.; Petersen, Ronald C.

    2014-01-01

    Although rates of incident dementia have been reported from several populations, the impact of nonparticipation on dementia incidence in studies of cognitive aging is unknown. In 2004, investigators with the Mayo Clinic Study of Aging selected persons aged 70–89 years from an enumeration of all Olmsted County, Minnesota, residents (age- and sex-stratified random sample). Of 4,398 potential participants, 2,050 agreed to undergo an in-person health assessment. Those participants were reevaluated in person using standard diagnostic procedures approximately every 15 months over a median follow-up period of 5.7 years (through September 15, 2013). There were 1,679 persons who refused any participation. A trained nurse abstractor reviewed the medical records of nonparticipants using the Rochester Epidemiology Project's medical record linkage system a median of 3.9 years after refusal. Nonparticipants had a higher prevalence of dementia than participants evaluated in person (6.5% vs. 3.3%; P < 0.0001). The standardized incidence of dementia was not significantly higher among the nonparticipants (23.2 per 1,000 person-years) than in those evaluated in person (19.6 per 1,000 person-years; hazard ratio = 1.17, 95% confidence interval: 0.95, 1.43 (P = 0.13); adjusted for education and sex, with age as the time scale). The small, nonsignificant impact of nonparticipation on rates of incident dementia is reassuring for future studies based on incident dementia cases. PMID:24859276

  1. Age estimation using development of third molars in South Indian population: A radiological study

    PubMed Central

    Priyadharshini, K. Indra; Idiculla, Jose Joy; Sivapathasundaram, B.; Mohanbabu, V.; Augustine, Dominic; Patil, Shankargouda

    2015-01-01

    Aim: To assess the estimation of chronological age based on the stages of third molar development following the eight stages (A–H) method of Demirjian et al. in Chennai population of South India. Materials and Methods: A sample consisting of 848 individuals (471 males and 377 females) aged between 14 and 30 years was randomly selected for the clinical evaluation and 323 orthopantomograms with clinically missing third molars were taken for radiological evaluation using Demirjian's method from a Chennai population of known chronological age and sex. Statistical analysis was performed using Pearson's Chi-square test and mean values were compared between the study groups using t-test or analysis of variance (ANOVA) followed by Tukey's highly significant difference (HSD). In the present study, P < 0.05 was considered as the level of significance. Results: The results showed that the mean age of having clinically completely erupted maxillary third molars was 22.41 years in male subjects and 23.81 years in female subjects and that of mandibular third molars was 21.49 years in male subjects and 23.34 years in female subjects. Mandibular third molars were clinically missing more often in females than in males. Eruption of mandibular third molars was generally ahead of the emergence of maxillary third molars into the oral cavity. Third molar development between male and female subjects showed statistically significant differences at calcification stage F and stage G in maxillary third molars and stage F in mandibular third molars (P < 0.05). Conclusion: There are differences indicating that maxillary and mandibular third molar eruption reached Demirjian's formation stages earlier in males than in females. It is suggested that in future studies, to increase the accuracy of age determination, indications of sexual maturity and ossification should also be evaluated in addition to third molar mineralization. PMID:25984465

  2. 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.

  3. Dynamic Links between Memory and Functional Limitations in Old Age: Longitudinal Evidence for Age-Based Structural Dynamics from the AHEAD Study

    PubMed Central

    Infurna, Frank J.; Gerstorf, Denis; Ryan, Lindsay H.; Smith, Jacqui

    2012-01-01

    This study examined competing substantive hypotheses about dynamic (i.e., time-ordered) links between memory and functional limitations in old age. We applied the Bivariate Dual Change Score Model to 13-year longitudinal data from the Asset and Health Dynamics Among the Oldest Old Study (AHEAD; N = 6,990; ages 70 – 95). Results revealed that better memory predicted shallower increases in functional limitations. Little evidence was found for the opposite direction that functional limitations predict ensuing changes in memory. Spline models indicated that dynamic associations between memory and functional limitations were substantively similar between participants aged 70–79 and those aged 80–95. Potential covariates (gender, education, health conditions, and depressive symptoms) did not account for these differential lead–lag associations. Applying a multivariate approach, our results suggest that late-life developments in two key components of successful aging are intrinsically interrelated. Our discussion focuses on possible mechanisms why cognitive functioning may serve as a source of age-related changes in health both among the young-old and the old-old. PMID:21480716

  4. Putting age-related task activation into large-scale brain networks: A meta-analysis of 114 fMRI studies on healthy aging.

    PubMed

    Li, Hui-Jie; Hou, Xiao-Hui; Liu, Han-Hui; Yue, Chun-Lin; Lu, Guang-Ming; Zuo, Xi-Nian

    2015-10-01

    Normal aging is associated with cognitive decline and underlying brain dysfunction. Previous studies concentrated less on brain network changes at a systems level. Our goal was to examine these age-related changes of fMRI-derived activation with a common network parcellation of the human brain function, offering a systems-neuroscience perspective of healthy aging. We conducted a series of meta-analyses on a total of 114 studies that included 2035 older adults and 1845 young adults. Voxels showing significant age-related changes in activation were then overlaid onto seven commonly referenced neuronal networks. Older adults present moderate cognitive decline in behavioral performance during fMRI scanning, and hypo-activate the visual network and hyper-activate both the frontoparietal control and default mode networks. The degree of increased activation in frontoparietal network was associated with behavioral performance in older adults. Age-related changes in activation present different network patterns across cognitive domains. The systems neuroscience approach used here may be useful for elucidating the underlying network mechanisms of various brain plasticity processes during healthy aging.

  5. Regional aortic distensibility and its relationship with age and aortic stenosis: a computed tomography study.

    PubMed

    Wong, Dennis T L; Narayan, Om; Leong, Darryl P; Bertaso, Angela G; Maia, Murilo G; Ko, Brian S H; Baillie, Timothy; Seneviratne, Sujith K; Worthley, Matthew I; Meredith, Ian T; Cameron, James D

    2015-06-01

    Aortic distensibility (AD) decreases with age and increased aortic stiffness is independently associated with adverse cardiovascular outcomes. The association of severe aortic stenosis (AS) with AD in different aortic regions has not been evaluated. Elderly subjects with severe AS and a cohort of patients without AS of similar age were studied. Proximal aortic cross-sectional-area changes during the cardiac cycle were determined using retrospective-ECG-gating on 128-detector row computed-tomography. Using oscillometric-brachial-blood-pressure measurements, the AD at the ascending-aorta (AA), proximal-descending-aorta (PDA) and distal-descending-aorta (DDA) was determined. Linear mixed effects modelling was used to determine the association of age and aortic stenosis on regional AD. 102 patients were evaluated: 36 AS patients (70-85 years), 24 AS patients (>85 years) and 42 patients without AS (9 patients <50 years, 20 patients between 51-70 years and 13 patients 70-85 years). When comparing patients 70-85 years, AA distensibility was significantly lower in those with AS compared to those without AS (0.9 ± 0.9 vs. 1.4 ± 1.1, P = 0.03) while there was no difference in the PDA (1.0 ± 1.1 vs. 1.0 ± 1.2, P = 0.26) and DDA (1.1 ± 1.2 vs. 1.2 ± 0.8, P = 0.97). In patients without AS, AD decreased with age in all aortic regions (P < 0.001). The AA in patients <50 years were the most distensible compared to other aortic regions. There is regional variation in aortic distensibility with aging. Patients with aortic stenosis demonstrated regional differences in aortic distensibility with lower distensibility demonstrated in the proximal ascending aorta compared to an age-matched cohort.

  6. A Case-Controlled Study of Successful Aging in Older Adults with HIV

    PubMed Central

    Moore, Raeanne C.; Moore, David J.; Thompson, Wesley; Vahia, Ipsit V.; Grant, Igor; Jeste, Dilip V.

    2013-01-01

    OBJECTIVES There is a growing public health interest in the aging HIV-infected (HIV+) population, although there is a dearth of research on successful aging with HIV. This study aimed to understand the risk and protective factors associated with self-rated successful aging (SRSA) with HIV. DESIGN Cross-sectional, case-controlled. SETTING HIV Neurobehavioral Research Program and the Stein Institute for Research on Aging at University of California, San Diego. PARTICIPANTS Eighty-three community-dwelling HIV+ and 83 demographically matched HIV-uninfected (HIV−) individuals, enrolled between 12/1/11 and 5/10/12, mean age of 59 years, primarily Caucasian males, 69% with AIDS, who had been living with an HIV diagnosis for 16 years. Diagnostic criteria for HIV/AIDS was obtained through a blood draw. MEASUREMENTS Participants provided ratings of SRSA as part of a comprehensive survey which included measures of physical and emotional functioning and positive psychological traits. Relationships between how the different variables related to SRSA were explored. RESULTS While SRSA was lower in the HIV+ individuals than their HIV− counterparts, 66% of adults with HIV reported scores of 5 or higher on a 10-point scale of SRSA. Despite worse physical and mental functioning and greater psychosocial stress among the HIV+ participants, the two groups had comparable levels of optimism, personal mastery, and social support. SRSA in HIV+ individuals was associated with better physical and emotional functioning and positive psychological factors, but not HIV disease status or negative life events. CONCLUSION Successful psychosocial aging is possible in older HIV+ individuals. Positive psychological traits such as resilience, optimism, and sense of personal mastery have stronger relationship with SRSA than duration or severity of HIV disease. Research on interventions to enhance these positive traits in HIV+ adults is warranted. PMID:23759460

  7. Psychosocial biomarker research: integrating social, emotional and economic factors into population studies of aging and health.

    PubMed

    Steptoe, Andrew

    2011-04-01

    There are complex reciprocal relationships between health and social, emotional and economic factors in aging populations. Social and affective neurosciences are rapidly developing an understanding of the mechanisms underlying these phenomena using sophisticated behavioural, neuroimaging and psychophysiological methods. These techniques are often complex and expensive, so are generally used in relatively small selected samples rather than in large-scale cohort studies. However, an understanding of the significance of these processes in health and well-being depends on integrating findings from social and affective neuroscience into population-level studies. The aim of this article is to describe how a population perspective on the determinants of health and well-being in old age articulates with the agenda of social, affective and economic neuroscience, particularly through the application of psychosocial biomarker research. Social and affective neuroscience and epidemiological approaches provide complementary research strategies for understanding the mechanisms linking social, emotional and economic factors with health risk. This will be illustrated primarily from findings from two studies conducted at University College London, the Whitehall II Study and the English Longitudinal Study of Ageing.

  8. The Douglas Hospital Longitudinal Study of Normal and Pathological Aging: summary of findings.

    PubMed

    Lupien, Sonia J; Schwartz, Georges; Ng, Ying Kin; Fiocco, Alexandra; Wan, Nathalie; Pruessner, Jens C; Meaney, Michael J; Nair, N P Vasavan

    2005-09-01

    In 1988, our group initiated the Douglas Hospital Longitudinal Study of Normal and Pathological Aging to assess the association between secretion of the stress hormone cortisol and cognitive performance in a group of 51 older adults. In this paper, we summarize the data obtained in this study to date. We have found that long-term exposure to high endogenous levels of cortisol is associated with both memory impairments and a 14; smaller volume of the hippocampus. We also report on studies showing that in older adults with moderate levels of cortisol over time, memory performance can be acutely modulated by pharmacologic manipulations of cortisol. We describe one participant who was included in the group of older adults presenting with increased cortisol levels over time, memory impairments and reduced hippocampal volume and in whom major depression, followed by Alzheimer's disease, developed during the course of the study. Together, the results of the Douglas Hospital Longitudinal Study of Normal and Pathological Aging show that increased secretion of cortisol in the older human population is significantly associated with impairment of cognitive function during aging.

  9. The Douglas Hospital Longitudinal Study of Normal and Pathological Aging: summary of findings

    PubMed Central

    Lupien, Sonia J.; Schwartz, Georges; Ng, Ying Kin; Fiocco, Alexandra; Wan, Nathalie; Pruessner, Jens C.; Meaney, Michael J.; Nair, N.P. Vasavan

    2005-01-01

    In 1988, our group initiated the Douglas Hospital Longitudinal Study of Normal and Pathological Aging to assess the association between secretion of the stress hormone cortisol and cognitive performance in a group of 51 older adults. In this paper, we summarize the data obtained in this study to date. We have found that long-term exposure to high endogenous levels of cortisol is associated with both memory impairments and a 14; smaller volume of the hippocampus. We also report on studies showing that in older adults with moderate levels of cortisol over time, memory performance can be acutely modulated by pharmacologic manipulations of cortisol. We describe one participant who was included in the group of older adults presenting with increased cortisol levels over time, memory impairments and reduced hippocampal volume and in whom major depression, followed by Alzheimer's disease, developed during the course of the study. Together, the results of the Douglas Hospital Longitudinal Study of Normal and Pathological Aging show that increased secretion of cortisol in the older human population is significantly associated with impairment of cognitive function during aging. PMID:16151537

  10. Continuity from Prelinguistic Communication to Later Language Ability: A Follow-Up Study from Infancy to Early School Age

    ERIC Educational Resources Information Center

    Määttä, Sira; Laakso, Marja-Leena; Tolvanen, Timo Ahonen Asko; Westerholm, Jari; Aro, Tuija

    2016-01-01

    Purpose: This longitudinal study examined the development of prelinguistic skills and the continuity of communication and language from the prelinguistic stage to school age. Method: Prelinguistic communication of 427 Finnish children was followed repeatedly from 6 to 18 months of age (n = 203-322 at ages 6, 9, 12, 15, and 18 months), and its…

  11. Saccadic Eye Movements in Normal Children from 8 to 15 Years of Age: A Developmental Study of Visuospatial Attention.

    ERIC Educational Resources Information Center

    Ross, Randal G.; And Others

    1994-01-01

    This study used saccadic eye movements to assess visuospatial attention in 53 normal children (ages 8-15). Saccadic latency, the ability to suppress extraneous saccades during fixation, and the ability to inhibit task-provoked anticipatory saccades all improved with age. Developmental patterns varied by task. Analyses of age-related changes may be…

  12. Is Age Kinder to the Initially More Able? Differential Ageing of Verbal Ability in the Healthy Old People in Edinburgh Study.

    ERIC Educational Resources Information Center

    Deary, Ian; MacLennan, William J.; Starr, John M.

    1998-01-01

    Results from a study of 387 healthy old people studied at baseline and four years later in Edinburgh (Scotland) suggest that, those with higher baseline ability, in higher social-class groups, with more education, and those who are younger are relatively protected from a decline in verbal intelligence, measured by an adult reading test, with age.…

  13. Estimation of gestational age, using neonatal anthropometry: a cross-sectional study in India.

    PubMed

    Thawani, Rajat; Dewan, Pooja; Faridi, M M A; Arora, Shilpa Khanna; Kumar, Rajeev

    2013-12-01

    Prematurity is a significant contributor to neonatal mortality in India. Conventionally, assessment of gestational age of newborns is based on New Ballard Technique, for which a paediatric specialist is needed. Anthropometry of the newborn, especially birthweight, has been used in the past to predict the gestational age of the neonate in peripheral health facilities where a trained paediatrician is often not available. We aimed to determine if neonatal anthropometric parameters, viz. birthweight, crown heel-length, head-circumference, mid-upper arm-circumference, lower segment-length, foot-length, umbilical nipple distance, calf-circumference, intermammary distance, and hand-length, can reliably predict the gestational age. The study also aimed to derive an equation for the same. We also assessed if these neonatal anthropometric parameters had a better prediction of gestational age when used in combination compared to individual parameters. We evaluated 1,000 newborns in a cross-sectional study conducted in Guru Teg Bahadur Hospital in Delhi. Detailed anthropometric estimation of the neonates was done within 48 hours after birth, using standard techniques. Gestational age was estimated using New Ballard Scoring. Out of 1,250 consecutive neonates, 1,000 were included in the study. Of them, 800 randomly-selected newborns were used in devising the model, and the remaining 200 newborns were used in validating the final model. Quadratic regression analysis using stepwise selection was used in building the predictive model. Birthweight (R=0.72), head-circumference (R = 0.60), and mid-upper arm-circumference (R = 0.67) were found highly correlated with gestation. The final equation to assess gestational age was as follows: Gestational age (weeks) = 5.437 x W-0.781 x W(2) + 2.815 x HC-0.041 x HC(2) + 0.285 x MUAC-22.745 where W=Weight, HC=Head-circumference and MUAC=Mid-upper arm-circumference; Adjusted R = 0.76. On validation, the predictability of this equation is 46

  14. [Clinical, biochemical and anthropometric studies and determination of biological age in relation to body mass in a longitudinal study].

    PubMed

    Hunecke, I; Reuter, W; Sauer, I; Ries, W

    1989-01-15

    On 46 adipose persons (25 males and 21 females) and 53 test persons with normal weight (35 males and 18 females) at the age of 25-40 years since 1976 clinical, biochemical and anthropometric investigations as well as the determination of the biological age have annually been performed. Several of the parameters established (e.g. cholesterol, triglycerides, fasting blood sugar, blood pressure among others) in the course of 9 years within the well-known normal regions draw towards the adequate valid limit value to the pathological entity. The results of the study distinctly show the central role of obesity for the development of risk factors. Despite the partly only with a certain tendency recognizable behaviour of single parameters after 9 years from our point of view the longitudinal method represents itself as a very well suitable method for establishing dynamic processes and risk factors of age.

  15. Is it possible to reverse aged acetylcholinesterase inhibited by organophosphorus compounds? Insight from the theoretical study.

    PubMed

    An, Yun; Zhu, Yali; Yao, Yuan; Liu, Junjun

    2016-04-14

    The main treatment for organophosphorus (OP) compound poisoning in clinics is to restore the activity of acetylcholinesterase (AChE) through oxime-induced reactivation of the phosphorylated OP-AChE adduct. It suffers from a competitive and irreversible aging reaction of the phosphorylated OP-AChE adduct, resulting in permanent inactivity of AChE. However, it was recently reported that N-methyl-2-methoxypyridinium species can act as methylating agents to methylate the methyl methane-phosphonate monoanion, in which the reaction mimics the reverse of the aging reaction of the phosphorylated OP-AChE adduct. If the aging reaction could be really reversed, the efficiency for the OP detoxification should be significantly improved, bringing up the possibility to develop an agent to reverse the aging process of the phosphorylated OP-AChE adduct. However, such a reaction with the N-methyl-2-methoxypyridinium species in the enzyme is still not reported so far. It is of great interest to know whether or not this reaction is observable in the enzyme, and more importantly, if it turns out to be not observable in the enzyme, why such a reaction proceeds quickly in aqueous solution but not in the enzyme. In the present study, we performed DFT calculations and quantum mechanical/molecular mechanical (QM/MM) calculations to reveal the fundamental mechanism for the methylation of both the methyl methane-phosphonate monoanion and the aged sarin-AChE adduct by N-methyl-2-methoxypyridinium species, respectively. The obtained results support the SN2 reaction mechanism, not the stepwise mechanism, for the methylation of the methyl methane-phosphonate monoanion by 9 reported N-methyl-2-methoxypyridinium compounds. The calculated free energy barriers are in good agreement with the experimental data. The methylation of the aged sarin-AChE adduct by one N-methyl-2-methoxypyridinium compound (labeled as compound 2) also employs the SN2 reaction mechanism with an extremely high free energy

  16. Morbidity, mortality and quality of life in the ageing haemodialysis population: results from the ELDERLY study

    PubMed Central

    Dschietzig, Wilfried; Leimenstoll, Gerd; Rob, Peter M.; Kuhlmann, Martin K.; Pommer, Wolfgang; Fraass, Uwe; Ritz, Eberhard; Schwenger, Vedat

    2016-01-01

    Background The physical–functional and social–emotional health as well as survival of the elderly (≥75 years of age) haemodialysis patient is commonly thought to be poor. In a prospective, multicentre, non-interventional, observational study, the morbidity, mortality and quality of life (QoL) in this patient group were examined and compared with a younger cohort. Methods In 92 German dialysis centres, 2507 prevalent patients 19–98 years of age on haemodialysis for a median of 19.2 months were included in a drug monitoring study of darbepoetin alfa. To examine outcome and QoL parameters, 24 months of follow-up data in the age cohorts <75 and ≥75 years were analysed. Treatment parameters, adverse and intercurrent events, hospitalizations, morbidity and mortality were assessed. QoL was evaluated by means of the 47-item Functional Assessment of Chronic Illness Therapy–Anaemia score (FACT-An, version 4). Results The 2-year mortality rate was 34.7% for the older cohort and 15.8% for the younger cohort. The mortality rate for the haemodialysed elderly patients was 6.2% higher in absolute value compared with the age-matched background population. A powerful predictor of survival was the baseline FACT-An score and a close correlation with the 20-item anaemia subscale (AnS) was demonstrated. While the social QoL in the elderly patients was more stable than in the younger cohort (leading to equivalent values at the end of the study period), a pronounced deterioration of physical and functional status was observed. The median number of all-cause hospital days per patient-year was 12.3 for the elderly cohort and 8.9 for the younger patient population. The overall 24-month hospitalization rate was only marginally higher in the elderly cohort (34.0 versus 33.3%). Conclusions In this observational study, the mortality rate of elderly haemodialysis patients was not exceedingly high compared with the age-matched background population. Furthermore, the hospitalization

  17. Perceptions of mental workload in Dutch university employees of different ages: a focus group study

    PubMed Central

    2013-01-01

    Background As academic workload seems to be increasing, many studies examined factors that contribute to the mental workload of academics. Age-related differences in work motives and intellectual ability may lead to differences in experienced workload and in the way employees experience work features. This study aims to obtain a better understanding of age differences in sources of mental workload. 33 academics from one faculty discussed causes of workload during focus group interviews, stratified by age. Findings Among our participants, the influence of ageing seems most evident in employees’ actions and reactions, while the causes of workload mentioned seemed largely similar. These individual reactions to workload may also be driven by differences in tenure. Most positively assessed work characteristics were: interaction with colleagues and students and autonomy. Aspects most often indicated as increasing the workload, were organisational aspects as obstacles for ‘getting the best out of people’ and the feeling that overtime seems unavoidable. Many employees indicated to feel stretched between the ‘greediness’ of the organisation and their own high working standards, and many fear to be assigned even less time for research if they do not meet the rigorous output criteria. Moreover, despite great efforts on their part, promotion opportunities seem limited. A more pronounced role for the supervisor seems appreciated by employees of all ages, although the specific interpretation varied between individuals and career stages. Conclusions To preserve good working conditions and quality of work, it seems important to scrutinize the output requirements and tenure-based needs for employee supervision. PMID:23506458

  18. Economic independence in survivors of cancer diagnosed at a young age: A Norwegian national cohort study

    PubMed Central

    Lie, Rolv Terje; Bjørge, Tone; Syse, Astri; Ruud, Ellen; Wesenberg, Finn; Moster, Dag

    2016-01-01

    BACKGROUND The impact of cancer on socioeconomic outcomes is attracting attention as the number of survivors of cancer in young age continues to rise. This study examines economic independence in a national cohort of survivors of cancer at a young age in Norway. METHODS Through the linkage of several national registries, the study cohort comprised 1,212,013 individuals born in Norway during 1965 through 1985, of which 5440 had received a cancer diagnosis before age 25 years. Follow‐up was through 2007, and the main outcomes were receipt of governmental financial assistance, employment, income, and occupation. Analytic methods included Cox proportional hazard regression, log‐binomial regression, and quantile regression models. RESULTS Individuals in the cancer survivor group had an increased probability of receiving governmental financial assistance (men: hazard ratio [HR], 1.4; 95% confidence interval [CI], 1.3‐1.5; women: HR, 1.5; 95% CI, 1.3‐1.6) and of not being employed (men: HR, 1.4; 95% CI, 1.2‐1.7; women: HR, 1.4; 95% CI, 1.2‐1.6) compared with those in the noncancer group. Income discrepancies were particularly pronounced for survivors of central nervous system tumors. There was no difference in representation in higher skilled occupations. CONCLUSIONS Survivors of cancer at a young age in Norway had an increased risk of being economically dependent and unemployed. This was evident in several tumor groups and was most pronounced in female survivors. There were only small differences in income or representation in higher skilled occupations for most employed survivors compared with the noncancer group. The current results are important for understanding the impact of a cancer diagnosis at a young age on subsequent job market outcomes. Cancer 2016;122:3873–3882. © 2016 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. PMID:27518040

  19. Hair elements and healthy aging: a cross-sectional study in Hainan Island, China.

    PubMed

    Hao, Zhe; Li, Yonghua; Liu, Yuan; Li, Hairong; Wang, Wuyi; Yu, Jiangping

    2016-06-01

    Healthy aging is considered as the core issue of aging population. Centenarians are a symbol of healthy aging. Concentration of elements in hair is an indicator of micronutrient status, which can affect the human health. In the present study, we investigated element concentrations in the scalp hair of 255 healthy centenarians from Hainan Island, China. The pattern of intergenerational transmission of elements and the effects of confounders such as sex, age, education level, smoking habits, alcohol intake, and frequency of hospitalization on hair element concentrations were assessed. For most elements, the load in hair increased significantly through intergenerational transmission (i.e., centenarians < children < grandchildren). Our results also demonstrated that female centenarians had significantly higher concentrations of Ca, Mg, Mn, Se, and Sr but lower levels of Cr and P. The Mn level was statistically significantly lower in the primary studies group. Alcohol intake was positively associated with Cd and Na levels, whereas smoking habits showed no significant effect on all the elements. Furthermore, the frequency of hospitalization was significantly positively associated with Cd, Cu, and Pb concentration. Moreover, our analysis suggested that adequate concentrations of Fe and Se might increase the life span of centenarians, whereas excessive concentrations of P and Pb were harmful to health and reduced life span. These results imply that element concentrations could be manipulated as a therapeutic modality in geriatric disease. They might also provide reference values for diseased subjects, allowing improved diagnoses and more effective therapies, which might support effective policies on health and aging.

  20. Upgrades to the Probabilistic NAS Platform Air Traffic Simulation Software

    NASA Technical Reports Server (NTRS)

    Hunter, George; Boisvert, Benjamin

    2013-01-01

    This document is the final report for the project entitled "Upgrades to the Probabilistic NAS Platform Air Traffic Simulation Software." This report consists of 17 sections which document the results of the several subtasks of this effort. The Probabilistic NAS Platform (PNP) is an air operations simulation platform developed and maintained by the Saab Sensis Corporation. The improvements made to the PNP simulation include the following: an airborne distributed separation assurance capability, a required time of arrival assignment and conformance capability, and a tactical and strategic weather avoidance capability.

  1. UAS-NAS Flight Test Series 3: Test Environment Report

    NASA Technical Reports Server (NTRS)

    Hoang, Ty; Murphy, Jim; Otto, Neil

    2016-01-01

    The desire and ability to fly Unmanned Aircraft Systems (UAS) in the National Airspace System (NAS) is of increasing urgency. The application of unmanned aircraft to perform national security, defense, scientific, and emergency management are driving the critical need for less restrictive access by UAS to the NAS. UAS represent a new capability that will provide a variety of services in the government (public) and commercial (civil) aviation sectors. The growth of this potential industry has not yet been realized due to the lack of a common understanding of what is required to safely operate UAS in the NAS. NASA's UAS Integration in the NAS Project is conducting research in the areas of Separation Assurance/Sense and Avoid Interoperability (SSI), Human Systems Integration (HSI), and Communications (Comm), and Certification to support reducing the barriers of UAS access to the NAS. This research is broken into two research themes namely, UAS Integration and Test Infrastructure. UAS Integration focuses on airspace integration procedures and performance standards to enable UAS integration in the air transportation system, covering Detect and Avoid (DAA) performance standards, command and control performance standards, and human systems integration. The focus of Test Infrastructure is to enable development and validation of airspace integration procedures and performance standards, including integrated test and evaluation. In support of the integrated test and evaluation efforts, the Project will develop an adaptable, scalable, and schedulable relevant test environment capable of evaluating concepts and technologies for unmanned aircraft systems to safely operate in the NAS. To accomplish this task, the Project is conducting a series of human-in-the-loop (HITL) and flight test activities that integrate key concepts, technologies and/or procedures in a relevant air traffic environment. Each of the integrated events will build on the technical achievements, fidelity, and

  2. Retinopathy in old persons with and without diabetes mellitus: the Age, Gene/Environment Susceptibility—Reykjavik Study (AGES-R)

    PubMed Central

    Gunnlaugsdottir, E.; Halldorsdottir, S.; Klein, R.; Eiriksdottir, G.; Klein, B. E.; Benediktsson, R.; Harris, T. B.; Launer, L. J.; Aspelund, T.; Gudnason, V.

    2012-01-01

    Aims/hypothesis We aimed to describe the prevalence of retinopathy in an aged cohort of Icelanders with and without diabetes mellitus. Methods The study population consisted of 4,994 persons aged ≥67 years, who participated in the Age, Gene/Environment Susceptibility—Reykjavik Study (AGES-R). Type 2 diabetes mellitus was defined as HbA1c ≥6.5% (>48 mmol/mol). Retinopathy was assessed by grading fundus photographs using the modified Airlie House adaptation of the Early Treatment Diabetic Retinopathy Study protocol. Associations between retinopathy and risk factors were estimated using odds ratios obtained from multivariate analyses. Results The overall prevalence of retinopathy in AGES-R was 12.4%. Diabetes mellitus was present in 516 persons (10.3%), for 512 of whom gradable fundus photos were available, including 138 persons (27.0%, 95% CI 23.2, 31.0) with any retinopathy. Five persons (1.0%, 95% CI 0.3, 2.3) had proliferative retinopathy. Clinically significant macular oedema was present in five persons (1.0%, 95% CI 0.3, 2.3). Independent risk factors for retinopathy in diabetic patients in a multivariate model included HbA1c, insulin use and use of oral hypoglycaemic agents, the last two being indicators of longer disease duration. In 4478 participants without diabetes mellitus, gradable fundus photos were available for 4,453 participants, with retinopathy present in 476 (10.7%, 95% CI 9.8, 11.6) and clinically significant macular oedema in three persons. Independent risk factors included increasing age and microalbuminuria. Conclusions/interpretation Over three-quarters (78%) of retinopathy cases were found in persons without diabetes and a strong association between microalbuminuria and non-diabetic retinopathy was found. These results may have implications for patient management of the aged. PMID:22134840

  3. Large-scale structural analysis: The structural analyst, the CSM Testbed and the NAS System

    NASA Technical Reports Server (NTRS)

    Knight, Norman F., Jr.; Mccleary, Susan L.; Macy, Steven C.; Aminpour, Mohammad A.

    1989-01-01

    The Computational Structural Mechanics (CSM) activity is developing advanced structural analysis and computational methods that exploit high-performance computers. Methods are developed in the framework of the CSM testbed software system and applied to representative complex structural analysis problems from the aerospace industry. An overview of the CSM testbed methods development environment is presented and some numerical methods developed on a CRAY-2 are described. Selected application studies performed on the NAS CRAY-2 are also summarized.

  4. 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

  5. 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

  6. A study of the use of clozapine in old age psychiatry.

    PubMed

    Snowdon, John; Halliday, Graeme

    2011-07-01

    The aim of this study was to review the use of clozapine in a Sydney area old age psychiatry service. Data were extracted from case files of all people who were treated in a health area's old age psychiatry units with clozapine during a 15-year period. Additional details were obtained from clinicians who provided ongoing care after discharge from the hospital. Note was made of psychiatric diagnoses, length of time taking clozapine, dosage, side effects and outcome. Sixteen patients aged over 65 years commenced or continued taking clozapine while inpatients of the service. Of the 13 patients who had a history of schizophrenia or schizoaffective disorder, four patients (all female) developed neutropenia and therefore clozapine was stopped. In one case, neutropenia was first diagnosed 6 years after commencing the medication. Two women died; the nine other women, and one of the deceased, stopped taking clozapine, usually because of side effects. The mean daily dose at cessation was 236 mg. All five men were still taking clozapine (mean 260 mg daily) when followed at a mean age of 72 years, having taken it for an average of 10 years. This case review adds to evidence of the risk of neutropenia when older people are prescribed clozapine.

  7. Age assessment by magnetic resonance imaging of the knee: a preliminary study.

    PubMed

    Dedouit, Fabrice; Auriol, Julien; Rousseau, Hervé; Rougé, Daniel; Crubézy, Eric; Telmon, Norbert

    2012-04-10

    The authors developed an original magnetic resonance imaging (MRI) staging system for epiphyseal fusion of growth plate maturation of the knee and evaluated its reliability and validity for age assessment of living individuals. A total of 290 MRI scans of the knee were reviewed retrospectively in patients aged from 10 to 30 years old (138 males, 152 females). Five original MRI stages were defined to assess the degree of maturation of the distal femoral and proximal tibial epiphyses. Intra-observer variability was excellent and inter-observer variability was good, demonstrating the reliability and the validity of this original MRI staging system. In both sexes, the changes of growth plates (proximal tibial or distal femoral) were associated with age (p<0.001). Our results agreed with classic data on skeletal maturation of the knee, with globally earlier maturation in females than in males, and also earlier maturation of the proximal tibial epiphysis than of the distal femoral epiphysis. MRI of the knee is an efficient non-invasive method of age assessment, without the disadvantage of X-ray exposure. Further studies with larger groups are needed to support our results.

  8. Challenges Experienced at Age 100: Findings From the Fordham Centenarian Study.

    PubMed

    Jopp, Daniela S; Boerner, Kathrin; Cimarolli, Verena; Hicks, Stephanie; Mirpuri, Sheena; Paggi, Michelle; Cavanagh, Andrew; Kennedy, Erin

    2016-01-01

    This article examines the challenges experienced by very old individuals and their consequences for well-being and mental health. In order to capture unique issues experienced in very old age, 75 participants of the population-based Fordham Centenarian Study answered open-ended questions on everyday challenges. Theme-based coding was then used to categorize and quantify responses. The challenges mentioned most often were challenges faced in the functional (e.g., physical health/activities of daily living restrictions, mobility, sensory impairment), psychological (e.g., loss of well-liked activity, dependency, negative emotions, death), and social (e.g., family loss) life domains. Functional challenges were negatively associated with aging satisfaction and positively associated with loneliness. Psychological challenges were positively linked to aging satisfaction. Social challenges were marginally related to loneliness. Notably, challenges were not related to depression. In conclusion, the challenges experienced in very old age are multidimensional and multifaceted, unique in nature, and have differential relations to mental health. Functional, psychological, and social challenges affect very old individuals' lives and therefore need to be better understood and addressed. Given their consequences, it is imperative for policy makers to develop an awareness for the different types of challenges faced by centenarians, as there may be unique policy implications related to each.

  9. Physical activity ameliorates cartilage degeneration in a rat model of aging: a study on lubricin expression.

    PubMed

    Musumeci, G; Castrogiovanni, P; Trovato, F M; Imbesi, R; Giunta, S; Szychlinska, M A; Loreto, C; Castorina, S; Mobasheri, A

    2015-04-01

    Osteoarthritis (OA) is a common musculoskeletal disorder characterized by slow progression and joint tissue degeneration. Aging is one of the most prominent risk factors for the development and progression of OA. OA is not, however, an inevitable consequence of aging and age-related changes in the joint can be distinguished from those that are the result of joint injury or inflammatory disease. The question that remains is whether OA can be prevented by undertaking regular physical activity. Would moderate physical activity in the elderly cartilage (and lubricin expression) comparable to a sedentary healthy adult? In this study we used physical exercise in healthy young, adult, and aged rats to evaluate the expression of lubricin as a novel biomarker of chondrocyte senescence. Immunohistochemistry and western blotting were used to evaluate the expression of lubricin in articular cartilage, while enzyme-linked immunosorbent assay was used to quantify lubricin in synovial fluid. Morphological evaluation was done by histology to monitor possible tissue alterations. Our data suggest that moderate physical activity and normal mechanical joint loading in elderly rats improve tribology and lubricative properties of articular cartilage, promoting lubricin synthesis and its elevation in synovial fluid, thus preventing cartilage degradation compared with unexercised adult rats.

  10. 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.

  11. Sexual protective strategies and condom use in middle-age African American women: A qualitative study

    PubMed Central

    Smith, Tanyka K.

    2015-01-01

    The heterosexual transmission of HIV has affected middle-age African American women at alarming rates; yet there is a paucity of research and interventions focused on this population. This study used a qualitative approach to understand middle-age urban African American women’s experiences with HIV-related sexual risk behaviors and to identify the sexual protective strategies they employed to reduce their risk for HIV infection. Ten African American women, ages 45 to 56, were recruited from low-income neighborhoods in New York City. Data were collected using in-depth interviews and analyzed using content analysis. Investigator triangulation and member checking were used to ensure rigor. Five salient themes emerged that highlighted the individual, gender/relationship power factors, and the sociocultural elements that influenced sexual protection or risk-taking behavior. Findings provide new insight into the complexities of HIV sexual risk behavior and can guide future HIV prevention interventions for middle-age, African American, urban women. PMID:26194973

  12. Mitochondrial DNA content contributes to healthy aging in Chinese: a study from nonagenarians and centenarians.

    PubMed

    He, Yong-Han; Lu, Xiang; Wu, Huan; Cai, Wang-Wei; Yang, Li-Qin; Xu, Liang-You; Sun, Hong-Peng; Kong, Qing-Peng

    2014-07-01

    Mitochondrial DNA (mtDNA) content plays an important role in energy production and sustaining normal physiological function. A decline in the mtDNA content and subsequent dysfunction cause various senile diseases, with decreasing mtDNA content observed in the elderly individuals with age-related diseases. In contrast, the oldest old individuals, for example, centenarians, have a delayed or reduced prevalence of these diseases, suggesting centenarians may have a different pattern of the mtDNA content, enabling them to keep normal mitochondrial functions to help delay or escape senile diseases. To test this hypothesis, a total of 961 subjects, consisting of 424 longevity subjects and 537 younger control subjects from Hainan and Sichuan provinces of China, were recruited for this study. The mtDNA content was found to be inversely associated with age among the age of group 40-70 years. Surprisingly, no reduction of mtDNA content was observed in nonagenarians and centenarians; instead, these oldest old showed a significant increase than the elderly people aged between 50 and 70 years. The results suggest the higher mtDNA content may convey a beneficial effect to the longevity of people through assuring sufficient energy supply.

  13. The methodology of the Italian HBSC 2010 study (Health Behaviour in School-aged Children).

    PubMed

    Lazzeri, G; Giacchi, M V; Dalmasso, P; Vieno, A; Nardone, P; Lamberti, A; Spinelli, A; Cavallo, F

    2013-01-01

    Italy has participated in the Health Behaviour in School-aged Children (HBSC) study since 2000. These surveys collect data every four years on the well-being and health behaviour of boys and girls aged 11, 13 and 15. Until 2007, the coordination group of the University of Turin, Siena and Padua directly sent the questionnaires to each sampled school to collect the data. The sample of about 4500 students was nationally representative. In 2008 the HBSC became part of the project "Surveys on behavioral risks in children aged 6-17 years", coordinated by the National Institute of Health (ISS) and promoted by the Ministry of Health, in collaboration with the Ministry of Education, University and Research. For the first time, in 2010, the survey was conducted by health workers in collaboration with teachers in all regions with a representative sample, not just at the national level, but also at regional level. In the 2,504 sampled schools, 77,113 students (25,079 eleven-year-old, 26,048 thirteen-year-old and 25,986 fifteen-year-old) completed an anonymous questionnaire. Knowledge of the health-related behaviour of school-aged adolescents may help monitoring and enable policies for young people to be formulated and implemented.

  14. 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.

  15. Cortical Thickness and Anxiety Symptoms Among Cognitively Normal Elderly Persons: The Mayo Clinic Study of Aging.

    PubMed

    Pink, Anna; Przybelski, Scott A; Krell-Roesch, Janina; Stokin, Gorazd B; Roberts, Rosebud O; Mielke, Michelle M; Spangehl, Kathleen A; Knopman, David S; Jack, Clifford R; Petersen, Ronald C; Geda, Yonas E

    2017-01-01

    The authors conducted a cross-sectional study to investigate the association between anxiety symptoms and cortical thickness, as well as amygdalar volume. A total of 1,505 cognitively normal participants, aged ≥70 years, were recruited from the Mayo Clinic Study of Aging in Olmsted County, Minnesota, on whom Beck Anxiety Inventory and 3T brain MRI data were available. Even though the effect sizes were small in this community-dwelling group of participants, anxiety symptoms were associated with reduced global cortical thickness and reduced thickness within the frontal and temporal cortex. However, after additionally adjusting for comorbid depressive symptoms, only the association between anxiety symptoms and reduced insular thickness remained significant.

  16. Molecular ageing: Free radical initiated epimerization of thymopentin – A case study

    SciTech Connect

    Sheykhkarimli, Dayag; Choo, Ken-Loon; Owen, Michael; Csizmadia, Imre G.; Fiser, Béla; Jójárt, Balázs; Viskolcz, Béla

    2014-05-28

    The epimerization of amino acid residues increases with age in living organisms. In the present study, the structural consequences and thermodynamic functions of the epimerization of thymopentin (TP-5), the active site of the thymic hormone thymopoietin, were studied using molecular dynamics and density functional theory methods. The results show that free radical-initiated D-amino acid formation is energetically favoured (−130 kJmol{sup −1}) for each residue and induces significant changes to the peptide structure. In comparison to the wild-type (each residue in the L-configuration), the radius of gyration of the D-Asp{sup 3} epimer of the peptide decreased by 0.5 Å, and disrupted the intramolecular hydrogen bonding of the native peptide. Beyond establishing important structural, energetic and thermodynamic benchmarks and reference data for the structure of TP-5, these results disseminate the understanding of molecular ageing, the epimerization of amino acid residues.

  17. Bullying behaviors among Chinese school-aged youth: a prevalence and correlates study in Guangdong Province.

    PubMed

    Wu, Jie; He, Yuan; Lu, Ciyong; Deng, Xueqing; Gao, Xue; Guo, Lan; Wu, Hong; Chan, Fanfan; Zhou, Ying

    2015-02-28

    Bullying among school-aged youth is a common issue worldwide and is increasingly being recognized as an important problem affecting both victims and perpetrators. Most of the bullying studies have been conducted in western countries, and their implications in other regions are limited due to different cultural contexts. The goal of our study is to identify the prevalence of bullying and its correlates school-aged youth in Guangdong province. In total, 1098 (7.1%) students reported having bullied other students, 744 (4.8%) students reported having been bullied by other students and 396 (2.6%) students reported having both bullied other students and been bullied by other students. There was a strong association between bullying others as well as being bullied and suicidal ideations, suicidal attempts, and self-harm behaviors. The prevalence of bullying and its associations with delinquent behaviors warrant the importance of school facility based preventive intervention taking into account both victims and perpetrators.

  18. Precautionary Savings in Mexico: Evidence from the Mexican Health and Aging Study.

    PubMed

    Velandia Naranjo, Durfari; van Gameren, Edwin

    2016-06-01

    Precautionary saving is the additional saving done by individuals to protect them financially in situations of uncertainty and reduce their vulnerability for negative shocks that may affect their consumption levels. This paper investigates the existence and extent of savings motivated by precaution in Mexico for people aged between 50 and 75, using data from the Mexican Health and Ageing Study 2003. The empirical strategy is based on a test of the direct relationship between the accumulated wealth and the uncertainty generated by the social security status, in particular the availability of health insurance, accounting also for the expectation to receive a retirement pension. The endogeneity-corrected estimates do not yield results that unequivocally support the existence of private savings as a risk protection mechanism, implying that the public protection system has an important role in reducing the vulnerability of the population studied.

  19. Longitudinal association between neighborhood cohesion and depressive mood in old age: A Japanese prospective study.

    PubMed

    Murayama, Hiroshi; Nishi, Mariko; Nofuji, Yu; Matsuo, Eri; Taniguchi, Yu; Amano, Hidenori; Yokoyama, Yuri; Fujiwara, Yoshinori; Shinkai, Shoji

    2015-07-01

    Despite increasing evidence of the relationship between neighborhood cohesion and depressive mood, little is known about this longitudinal association in old age. This study examined the association between perceived neighborhood cohesion and depressive mood and the stress-buffering effect of perceived neighborhood cohesion on depressive mood among older Japanese people using the 2010 (baseline) and 2012 (follow-up) Hatoyama Cohort Study datasets. We analyzed 655 participants aged 65-84 at baseline. Although perceived neighborhood cohesion at baseline was not associated with depressive mood at follow-up, high neighborhood cohesion partially offset the deleterious effect of anticipated daily stressors on depressive mood. This effect was stronger for long-term residents of the neighborhood. Interventions to strengthen neighborhood cohesion may help reduce the deleterious effect of stressors on older residents' depressive mood.

  20. Age-related differential sensitivity to cadmium in Hyalella curvispina (Amphipoda) and implications in ecotoxicity studies.

    PubMed

    García, M E; Rodrígues Capítulo, A; Ferrari, L

    2010-07-01

    The standardization of toxicity tests requires the selection of the most suitable test species and their developmental stages, as well as the selection of the appropriate assay matrix and the evaluation of the sensitivity of the test species to the reference toxicants. International protocols recommend the use of the amphipod Hyalella azteca from the Northern Hemisphere for sediment toxicity tests. We selected the widely distributed amphipod Hyalella curvispina, representative of pleustonic, epiphitic and zoobenthic assemblages in austral South America, as test species to be used in regional studies. Our goals were to evaluate the sensitivity of three developmental stages of H. curvispina to cadmium as a reference toxicant and to select the most suitable age and exposure time for aquatic ecotoxicity assessment. The three ages were highly susceptible to cadmium, with sensitivities: neonates > adults > juveniles. Our results validate the use of the native H. curvispina as a standard species for ecotoxicological assessment studies.

  1. 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

  2. Factors associated with the age of the onset of diabetes in women aged 50 years or more: a population-based study

    PubMed Central

    Valadares, Ana L R; Machado, Vanessa S S; Costa-Paiva, Lúcia S; de Sousa, Maria H; Pinto-Neto, Aarão M

    2014-01-01

    Objective Investigate factors associated with the onset of diabetes in women aged more than 49 years. Design and methods Cross-sectional, population-based study using self-reports with 622 women. The dependent variable was the age of occurrence of diabetes using the life table method. Cox multiple regression models were adjusted to analyse the onset of diabetes according to predictor variables. Sociodemographic, clinical and behavioural factors were evaluated. Results Of the 622 women interviewed, 22.7% had diabetes. The mean age at onset was 56 years. The factors associated with the age of occurrence of diabetes were self-rated health (very good, good) (coefficient=−0.792; SE of the coefficient=0.215; p=0.0001), more than two individuals living in the household (coefficient=0.656, SE of the coefficient=0.223; p=0.003), and body mass index (BMI) (kg/m2) at 20–30 years of age (coefficient= 0.056, SE of the coefficient=0.023; p=0.014). Conclusions Self-rated health considered good or very good was associated with a higher rate of survival without diabetes. Sharing a home with two or more other people and a weight increase at 20–30 years of age was associated with the onset of type 2 diabetes. PMID:25428628

  3. Challenges in Recruiting Aging Women Holocaust Survivors to a Case Control Study of Breast Cancer.

    PubMed

    Vin-Raviv, Neomi; Dekel, Rachel; Barchana, Micha; Linn, Shai; Keinan-Boker, Lital

    2015-01-01

    Older adults are underrepresented in medical research for many reasons, including recruitment difficulties. Recruitment of older adults for research studies is often a time-consuming process and can be more challenging when the study involves older adults with unique exposures to traumatic events and from minority groups. The current article provides a brief overview of (a) challenges encountered while recruiting aging women Holocaust survivors for a case control study and (b) strategies used for meeting those challenges. The case group comprised women Holocaust survivors who were recently diagnosed with breast cancer and the control group comprised healthy women from a Holocaust-survivor community in Israel.

  4. Cohort Profile: The Social Environment and Biomarkers of Aging Study (SEBAS) in Taiwan

    PubMed Central

    Cornman, Jennifer C; Glei, Dana A; Goldman, Noreen; Chang, Ming-Cheng; Lin, Hui-Sheng; Chuang, Yi-Li; Hurng, Baai-Shyun; Lin, Yu-Hsuan; Lin, Shu-Hui; Liu, I-Wen; Liu, Hsia-Yuan; Weinstein, Maxine

    2016-01-01

    The Social Environment and Biomarkers of Aging Study (SEBAS) is a nationally representative longitudinal survey of Taiwanese middle-aged and older adults. It adds the collection of biomarkers and performance assessments to the Taiwan Longitudinal Study of Aging (TLSA), a nationally representative study of adults aged 60 and over, including the institutionalized population. The TLSA began in 1989, with follow-ups approximately every 3 years; younger refresher cohorts were added in 1996 and 2003. The first wave of SEBAS, based on a sub-sample of respondents from the 1999 TLSA, was conducted in 2000. A total of 1023 respondents completed both a face-to-face home interview and, several weeks later, a hospital-based physical examination. In addition to a 12-h (7 pm–7 am) urine specimen collected the night before and a fasting blood specimen collected during the examination, trained staff measured blood pressure, height, weight and waist and hip circumferences. A second wave of SEBAS was conducted in 2006 using a similar protocol to SEBAS 2000, but with the addition of performance assessments conducted by the interviewers at the end of the home interview. Both waves of SEBAS also included measures of health status (physical, emotional, cognitive), health behaviours, social relationships and exposure to stressors. The SEBAS data, which are publicly available at [http://www.icpsr.umich.edu/icpsrweb/NACDA/studies/3792/version/5], allow researchers to explore the relationships among life challenges, the social environment and health and to examine the antecedents, correlates and consequences of change in biological measures and health. PMID:25205853

  5. Studying beyond Age 25: Who Does It and What Do They Gain? Research Report

    ERIC Educational Resources Information Center

    Coelli, Michael; Tabasso, Domenico; Zakirova, Rezida

    2012-01-01

    Why should a person keep studying beyond his/her mid-20s? After all, education and training at a younger age provide for the longest period over which the return on the investment can be harvested. On the other hand, individuals in their 40s (or even 50s) can expect to work for another 20 years or so, allowing plenty of time to recoup the cost of…

  6. The Literacy Factor in the Optimal Age Discussion: A Five-Year Longitudinal Study

    ERIC Educational Resources Information Center

    Pfenninger, Simone E.

    2016-01-01

    This study examines the impact of L2 literacy on the development of writing proficiency in the L3, as related to age of onset (AO) of instruction, as well as the effects of AO on ultimate L3 attainment at the end of the period of normal schooling. Using longitudinal data for the same student cohort (200 Swiss learners of English) at the beginning…

  7. The USAFSAM Cardiovascular Disease Followup Study: Clinical Evaluation of Subjects Near Age 43.

    DTIC Science & Technology

    1982-08-01

    Right bundle branch block 2 Terminal IV conduction defect 10 Left bundle branch block 3 Left anterior fascicular block, persistent 2 Unclassified IV... ventricular hypertrophy (EOG only) 8 Septal hypertrophy 3 Myocardial damage 6 Atherosclerotic Coronary Disease 10 Thyroid Enlargement 3 Hypothyroldism 3...early years of the Framingham study (41), electrocardiographic evidence of left ventricular hypertrophy (LVH) in middle-aged people was iden- tified as

  8. Preclinical Magnetic Resonance Imaging and Spectroscopy Studies of Memory, Aging, and Cognitive Decline

    PubMed Central

    Febo, Marcelo; Foster, Thomas C.

    2016-01-01

    Neuroimaging provides for non-invasive evaluation of brain structure and activity and has been employed to suggest possible mechanisms for cognitive aging in humans. However, these imaging procedures have limits in terms of defining cellular and molecular mechanisms. In contrast, investigations of cognitive aging in animal models have mostly utilized techniques that have offered insight on synaptic, cellular, genetic, and epigenetic mechanisms affecting memory. Studies employing magnetic resonance imaging and spectroscopy (MRI and MRS, respectively) in animal models have emerged as an integrative set of techniques bridging localized cellular/molecular phenomenon and broader in vivo neural network alterations. MRI methods are remarkably suited to longitudinal tracking of cognitive function over extended periods permitting examination of the trajectory of structural or activity related changes. Combined with molecular and electrophysiological tools to selectively drive activity within specific brain regions, recent studies have begun to unlock the meaning of fMRI signals in terms of the role of neural plasticity and types of neural activity that generate the signals. The techniques provide a unique opportunity to causally determine how memory-relevant synaptic activity is processed and how memories may be distributed or reconsolidated over time. The present review summarizes research employing animal MRI and MRS in the study of brain function, structure, and biochemistry, with a particular focus on age-related cognitive decline. PMID:27468264

  9. 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.

  10. Impaired Vestibular Function and Low Bone Mineral Density: Data from the Baltimore Longitudinal Study of Aging.

    PubMed

    Bigelow, Robin T; Semenov, Yevgeniy R; Anson, Eric; du Lac, Sascha; Ferrucci, Luigi; Agrawal, Yuri

    2016-10-01

    Animal studies have demonstrated that experimentally induced vestibular ablation leads to a decrease in bone mineral density, through mechanisms mediated by the sympathetic nervous system. Loss of bone mineral density is a common and potentially morbid condition that occurs with aging, and we sought to investigate whether vestibular loss is associated with low bone mineral density in older adults. We evaluated this question in a cross-sectional analysis of data from the Baltimore Longitudinal Study of Aging (BLSA), a large, prospective cohort study managed by the National Institute on Aging (N = 389). Vestibular function was assessed with cervical vestibular evoked myogenic potentials (cVEMPs), a measure of saccular function. Bone mineral density was assessed using dual-energy X-ray absorptiometry (DEXA). In two-way t test analysis, we observed that individuals with reduced vestibular physiologic function had significantly lower bone mineral density. In adjusted multivariate linear regression analyses, we observed that older individuals with reduced vestibular physiologic function had significantly lower bone mineral density, specifically in weight-bearing hip and lower extremity bones. These results suggest that the vestibular system may contribute to bone homeostasis in older adults, notably of the weight-bearing hip bones at greatest risk of osteoporotic fracture. Further longitudinal analysis of vestibular function and bone mineral density in humans is needed to characterize this relationship and investigate the potential confounding effect of physical activity.

  11. Invited Commentary: Lessons for Research on Cognitive Aging From a Study of Children.

    PubMed

    Belsky, Daniel W

    2016-06-15

    As the population ages, the burden of disease from cognitive decline and dementing illness is rising. In the absence of treatments to reverse cognitive decline, prevention is a public health priority. Physical fitness and physical activity have emerged as prevention targets based on evidence of "neuroprotective" benefits in observational studies. However, observational studies linking active lifestyle with successful cognitive aging might be subject to bias from "neuroselection," in which adults with better cognitive functioning are more likely to engage in healthy behaviors and avoid unhealthy ones. In their analysis of longitudinal data on several thousand children from the United Kingdom's Millennium Cohort Study, Aggio et al. (Am J Epidemiol. 2016;183(12):1075-1082) revealed that this pattern of neuroselection is already apparent in childhood. However, they also report data that suggest there are cognitive benefits to engaging in certain types of active behaviors over and above this selection. Their findings argue for greater attention to confounding by neuroselection in research on cognitive aging, and they suggest the possibility that early interventions to promote certain health behaviors may instill a virtuous cycle with benefits that accumulate across the lifespan.

  12. Influence of Perceived Stress on Incident Amnestic Mild Cognitive Impairment: Results From the Einstein Aging Study.

    PubMed

    Katz, Mindy J; Derby, Carol A; Wang, Cuiling; Sliwinski, Martin J; Ezzati, Ali; Zimmerman, Molly E; Zwerling, Jessica L; Lipton, Richard B

    2016-01-01

    Stress is a potentially remediable risk factor for amnestic mild cognitive impairment (aMCI). Our objective is to determine whether perceived stress predicts incident aMCI and to determine if the influence of stress on aMCI is independent of known aMCI risk factors, particularly demographic variables, depression, and apolipoprotein genotype. The Einstein Aging Study is a longitudinal community-based study of older adults. The Perceived Stress Scale (PSS) was administered annually in the Einstein Aging Study to participants (N=507; 71 developed incident aMCI; mean follow-up time=3.6 y, SD=2.0) who were aged 70 years and older, free of aMCI and dementia at baseline PSS administration, and had at least 1 subsequent annual follow-up. Cox hazard models were used to examine time to aMCI onset adjusting for covariates. High levels of perceived stress are associated with a 30% greater risk of incident aMCI (per 5-point increase in PSS: hazard ratio=1.30; 95% confidence interval, 1.08-1.58) independent of covariates. The consistency of results after covariate adjustment and the lack of evidence for reverse causation in longitudinal analyses suggest that these findings are robust. Understanding of the effect of perceived stress on cognition may lead to intervention strategies that prevent the onset of aMCI and Alzheimer dementia.

  13. Is complexity of work associated with risk of dementia? The Canadian Study of Health And Aging.

    PubMed

    Kröger, Edeltraut; Andel, Ross; Lindsay, Joan; Benounissa, Zohra; Verreault, René; Laurin, Danielle

    2008-04-01

    The authors evaluated the association of complexity of work with data, people, and things with the incidence of dementia, Alzheimer's disease, and vascular dementia in the Canadian Study of Health and Aging, while adjusting for work-related physical activity. The Canadian Study of Health and Aging is a 10-year population study, from 1991 to 2001, of a representative sample of persons aged 65 years or older. Lifetime job history allowed application of complexity scores and classification of work-related physical activity. Analyses included 3,557 subjects, of whom 400 were incident dementia cases, including 299 with Alzheimer's disease and 93 with vascular dementia. In fully adjusted Cox regression models, high complexity of work with people or things reduced risk of dementia (hazard ratios were 0.66 (95% confidence interval: 0.44, 0.98) and 0.72 (95% confidence interval: 0.52, 0.99), respectively) but not Alzheimer's disease. For vascular dementia, hazard ratios were 0.36 (95% confidence interval: 0.15, 0.90) for high complexity of work with people and 0.50 (95% confidence interval: 0.25, 1.00) for high complexity of work with things. Subgroup analyses according to median duration (23 years) of principal occupation showed that associations with complexity varied according to duration of employment. High complexity of work appears to be associated with risk of dementia, but effects may vary according to subtype.

  14. Cerebral cortex: an MRI-based study of volume and variance with age and sex.

    PubMed

    Carne, Ross P; Vogrin, Simon; Litewka, Lucas; Cook, Mark J

    2006-01-01

    The aim of the present study was to examine quantitative differences in lobar cerebral cortical volumes in a healthy adult population. Quantitative volumetric MRI of whole brain, cerebral and cerebellar volumes was performed in a cross-sectional analysis of 97 normal volunteers, with segmented frontal, temporal, parietal and occipital cortical volumes measured in a subgroup of 60 subjects, 30 male and 30 female, matched for age and sex. The right cerebral hemisphere was larger than the left across the study group with a small (<1%) but significant difference in symmetry (P<0.001). No difference was found between volumes of right and left cerebellar hemispheres. Rightward cerebral cortical asymmetry (right larger than left) was found to be significant across all lobes except parietal. Males had greater cerebral, cerebellar and cerebral cortical lobar volumes than females. Larger male cerebral cortical volumes were seen in all lobes except for left parietal. Females had greater left parietal to left cerebral hemisphere and smaller left temporal to left cerebral hemisphere ratios. There was a mild reduction in cerebral volumes with age, more marked in males. This study confirms and augments past work indicating underlying structural asymmetries in the human brain, and provides further evidence that brain structures in humans are differentially sensitive to the effects of both age and sex.

  15. Recombination and maternal age-dependent nondisjunction: Molecular studies of trisomy 16

    SciTech Connect

    Hassold, T.; Merrill, M.; Adkins, K.

    1995-10-01

    Trisomy 16 is the most common human trisomy, occurring in {ge} 1% of all clinically recognized pregnancies. It is thought to be completely dependent on maternal age and thus provides a useful model for studying the association of increasing maternal age and nondisjunction. We have been conducting a study to determine the parent and meiotic stage of origin of trisorny 16 and the possible association of nondisjunction and aberrant recombination. In the present report, we summarize our observations on 62 spontaneous abortions with trisomy 16. All trisomies were maternally derived, and in virtually all the error occurred at meiosis I. In studies of genetic recombination, we observed a highly significant reduction in recombination in the trisomy-generating meioses by comparison with normal female meioses. However, most cases of trisomy 16 had at least one detectable crossover between the nondisjoined chromosomes, indicating that it is reduced-and not absent-recombination that is the important predisposing factor. Additionally, our data indicate an altered distribution of crossing-over in trisomy 16, as we rarely observed crossovers in the proximal long and short arms. Thus, it may be that, at least for trisomy 16, the association between maternal age and trisomy is due to diminished recombination, particularly in the proximal regions of the chromosome. 34 refs., 2 figs., 2 tabs.

  16. 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

  17. Age-related brain trajectories in schizophrenia: a systematic review of structural MRI studies.

    PubMed

    Chiapponi, Chiara; Piras, Fabrizio; Fagioli, Sabrina; Piras, Federica; Caltagirone, Carlo; Spalletta, Gianfranco

    2013-11-30

    Using the Pubmed database, we performed a detailed literature search for structural magnetic resonance imaging studies on patients with schizophrenia, investigating the relationship between macroscopic and microscopic structural parameters and age, to delineate an age-related trajectory. Twenty-six studies were considered for the review, from January 2000 to June 2012. Research results are heterogeneous because of the multifactorial features of schizophrenia and the multiplicity of the methodological approaches adopted. Some areas, within the amygdala-hippocampus complex, which are affected early in life by schizophrenia, age in a physiological way. Other regions, such as the superior temporal gyrus, appear already impaired at the onset of symptoms, undergo a worsening in the acute phase but later stabilize, progressing physiologically over years. Finally, there are regions, such as the uncinate fasciculus, which are not altered early in life, but are affected around the onset of schizophrenia, with their impairment continuously worsening over time. Further extensive longitudinal studies are needed to understand the timing and the possible degenerative characteristics of structural imp